US3887742A - Copy resistant documents - Google Patents

Copy resistant documents Download PDF

Info

Publication number
US3887742A
US3887742A US243743A US24374372A US3887742A US 3887742 A US3887742 A US 3887742A US 243743 A US243743 A US 243743A US 24374372 A US24374372 A US 24374372A US 3887742 A US3887742 A US 3887742A
Authority
US
United States
Prior art keywords
sheet
graphical information
document
reflectance
copy
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US243743A
Inventor
Richard E Reinnagel
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US243743A priority Critical patent/US3887742A/en
Priority to US05/562,512 priority patent/US4025673A/en
Application granted granted Critical
Publication of US3887742A publication Critical patent/US3887742A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41MPRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
    • B41M1/00Inking and printing with a printer's forme
    • B41M1/26Printing on other surfaces than ordinary paper
    • B41M1/36Printing on other surfaces than ordinary paper on pretreated paper, e.g. parchment, oiled paper, paper for registration purposes
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B42BOOKBINDING; ALBUMS; FILES; SPECIAL PRINTED MATTER
    • B42DBOOKS; BOOK COVERS; LOOSE LEAVES; PRINTED MATTER CHARACTERISED BY IDENTIFICATION OR SECURITY FEATURES; PRINTED MATTER OF SPECIAL FORMAT OR STYLE NOT OTHERWISE PROVIDED FOR; DEVICES FOR USE THEREWITH AND NOT OTHERWISE PROVIDED FOR; MOVABLE-STRIP WRITING OR READING APPARATUS
    • B42D25/00Information-bearing cards or sheet-like structures characterised by identification or security features; Manufacture thereof
    • B42D25/20Information-bearing cards or sheet-like structures characterised by identification or security features; Manufacture thereof characterised by a particular use or purpose
    • B42D25/29Securities; Bank notes
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B42BOOKBINDING; ALBUMS; FILES; SPECIAL PRINTED MATTER
    • B42DBOOKS; BOOK COVERS; LOOSE LEAVES; PRINTED MATTER CHARACTERISED BY IDENTIFICATION OR SECURITY FEATURES; PRINTED MATTER OF SPECIAL FORMAT OR STYLE NOT OTHERWISE PROVIDED FOR; DEVICES FOR USE THEREWITH AND NOT OTHERWISE PROVIDED FOR; MOVABLE-STRIP WRITING OR READING APPARATUS
    • B42D25/00Information-bearing cards or sheet-like structures characterised by identification or security features; Manufacture thereof
    • B42D25/30Identification or security features, e.g. for preventing forgery
    • B42D25/324Reliefs
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B42BOOKBINDING; ALBUMS; FILES; SPECIAL PRINTED MATTER
    • B42DBOOKS; BOOK COVERS; LOOSE LEAVES; PRINTED MATTER CHARACTERISED BY IDENTIFICATION OR SECURITY FEATURES; PRINTED MATTER OF SPECIAL FORMAT OR STYLE NOT OTHERWISE PROVIDED FOR; DEVICES FOR USE THEREWITH AND NOT OTHERWISE PROVIDED FOR; MOVABLE-STRIP WRITING OR READING APPARATUS
    • B42D25/00Information-bearing cards or sheet-like structures characterised by identification or security features; Manufacture thereof
    • B42D25/30Identification or security features, e.g. for preventing forgery
    • B42D25/351Translucent or partly translucent parts, e.g. windows
    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03CPHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
    • G03C5/00Photographic processes or agents therefor; Regeneration of such processing agents
    • G03C5/08Photoprinting; Processes and means for preventing photoprinting
    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03GELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G21/00Arrangements not provided for by groups G03G13/00 - G03G19/00, e.g. cleaning, elimination of residual charge
    • G03G21/04Preventing copies being made of an original
    • G03G21/043Preventing copies being made of an original by using an original which is not reproducible or only reproducible with a different appearence, e.g. originals with a photochromic layer or a colour background
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41MPRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
    • B41M3/00Printing processes to produce particular kinds of printed work, e.g. patterns
    • B41M3/14Security printing
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S283/00Printed matter
    • Y10S283/902Anti-photocopy
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S428/00Stock material or miscellaneous articles
    • Y10S428/913Material designed to be responsive to temperature, light, moisture
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S428/00Stock material or miscellaneous articles
    • Y10S428/916Fraud or tamper detecting
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T428/00Stock material or miscellaneous articles
    • Y10T428/24Structurally defined web or sheet [e.g., overall dimension, etc.]
    • Y10T428/24802Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]
    • Y10T428/24934Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.] including paper layer

Definitions

  • This invention relates generally to the production of documents and the like having copy resistant characteristics and, more particularly, to copy resistant documents and to methods for treating or producing original documents in such a manner so as to yield easily readable documents under normal reading conditions but inhibiting, if not preventing, the reproduction of intelligible copies thereof by conventional copying processes.
  • Copying machines have become increasingly popular in recent years and can be found in most business of fices and in public areas, such as shopping centers, hotel lobbies and the like. Because of the widespread availability of various types of copying machines, the ease with which they can be operated, and the low cost of each copy, virtually all documents are susceptible to be copied to anyone without the consent of the originator or owner While the development of these copying machines certainly represents progress in the graphical communication field, they are often used to copy documents which maybe abusive to the originator or owner. For example, the unauthorized and indiscriminate copying of materials such as news letters, poems, sheet music, drawings etc, may violate the legal rights of the publishers and/or authors denying to them the compen sation to which they are entitled. Also, security can be flagrantly breached by copying material of a sensitive nature such as classified government information, industrial and commercial data. and personal correspondence of a confidential nature.
  • FIG. is a diagrammatic view illustrating the effects of color and low reflectance filters on a graph which correlates the color or spectral response of the human eye and a copying machine in percentages to wavelengths of light in millimicrons;
  • FIG. 2 is a fragmentary, perspective, exaggerated view of a copy resistant document constructed in accordance with one form of this invention
  • FIG. 3 is a fragmentary side elevational view, on a greatly enlarged scale, of another form of a copy resistant document of this invention.
  • FIG. 4 is a fragmentary side elevational view, greatly enlarged, of still another form of a copy resistant document of the present invention:
  • FIG. 5 is a fragmentary side elevational view, greatly exaggerated, of another embodiment of the form of copy resistant document shown in FIG. 4;
  • FIG. 6 is a fragmentary, perspective, exaggerated view of still another form of a copy resistant document of this invention.
  • FIG. 7 is a fragmentary side elevational view, on a greatly enlarged scale, of the document shown in FIG.
  • FIG. 8 is a view similar to FIG. 7 illustrating another embodiment of the form of this invention shown in FIG. 7;
  • FIG. 9 is a fragmentary side elevational view, greatly exaggerated, illustrating still another embodiment of a copy resistant document constructed in accordance with the present invention.
  • FIG. 10 is an exaggerated fragmentary plan view of yet another form of copy resistant document of this invention.
  • FIG. 11 is a fragmentary side elevational view, of the document shown in FIG. I0;
  • FIG. 12 is a diagrammatic view similar to FIG. 1 illustrating a graph which correlates the color or spectral responses of the human eye and :1 copying machine in percentages to wavelengths of light in millimicrons.
  • the required contrast can be in the form of a color difference between two colors of the same density or reflectance, or a reflectance contrast between two shades of a given color, such as a light blue color as opposed to a dark blue color, or a combination of both color contrast and reflectance or density contrast,
  • Reflectance or density as used herein is: Log l (Incident light)/(Reflected light). Reflectance can also be ex pressed as the percentage of the incident light that is reflected.
  • the spectral or color sensitivity of these known copying machines do not match the sensitivity and density range of the human eye.
  • Density range is conveniently referred to as the range of values of reflectance over which the eye can recognize a change in reflectance.
  • the eye may not recognize a slight change in reflectance when the reflectance is near 100% as in white, or 0% as in black.
  • the eye tends to have a linear response to changes in density between 0.05 and 1.05, corresponding to a reflectance of 90% and 8%, respectively.
  • Copying processes generally have a much smaller dynamic range than the eye, such as 0.3 to 0.6. and this density range can generally be moved between the limits of 0.05 and l.(] by an adjustment of the exposure control on the machine.
  • the limited dynamic range of these copying processes tends to produce a black and white copy with poorer gray scale than in the original.
  • the principles of this invention contemplate a multiplicity of techniques. which can be used singly or in combination, to treat an original document in such a manner as to affect the color and/or reflectance or density contrast between the background and the graphical information to maintain the original easily readable, or to render the document readable at certain viewing angles, but to adversely affect the image reproduced by the copying machine to produce a copy which is unintelligible or at least less intelligible than the original document.
  • the original is treated so as to favor the responses of the human eye but inhibit the responses of copying machines to prevent the production of a usable copy.
  • the degree of copy resistance imparted to the original is generally dictated by the sensitivity of the material disclosed in the document, and, since any document can be manually copied, the extent of copy resistance need only be sufficient to render automatic or direct copying by means of copying machines at least as expensive and more complicated than manual copying.
  • the term original as used herein is intended to embrace any document to be copied, whether it be the true original or a copy or reproduction thereof.
  • one method employed to favor the spectral response of the human eye over the spectral response of the copying machine is in the selection of different colors or color filters.
  • the choice of a color or colored filter should be based upon the spectral sensitivity or color response of known copying machines and the human eye and optimized to obtain the least loss in contrast and reading comfort while yielding a maximum in color contrast reduction at the copying machine receptor, with due consideration given to the spectral characteristics of the source of illumination for both the copy machine and the human eye.
  • the color can be applied to the paper stock as a dye or as a coating before the graphical information is printed on the background.
  • the filter can be provided in the form of a film of a transparent colored plastic material or of a clear plastic material provided with a colored adhesive and applied to the document to be protected by any suitable or conventional laminating process, or the film can be produced as a pressure sensitive tape adapted to be applied from a roll to cover the entire surface of the document, or only isolated areas thereof, as desired.
  • the film could be dispensed from a specially designed machine attached to the office copying machine and applied to the copies reproduced from the original so as to prevent such copies from being further copied by the various known copying systems.
  • Another form of this invention is the utilization of low reflectance backgrounds with low reflectance graphical information imprinted thereon. It is known that dark or deep colors reflect less light than bright or light colors. Thus, dark or low reflectance graphical information disposed on a low reflectance background reflects less of the incident light and therefore less energy to the sensor or image forming surface in lightactivated copying machines.
  • low reflectance or dark backgrounds are used with low reflectance graphical information, the copying process must usually be adjusted to operate at maximum exposure to yield a useful copy, if indeed a copy can be made. I have found that gray background density of 0.4, when used with printing inks of densities above 1, will produce marginally readable copies when the copy machine is operated at the maximum exposure condition. However, the originals so produced are very comfortable and easy to read.
  • FIG. 1 graphically illustrates the effect of the combi nation of a color filter and a low reflectance filter on a graph which correlates the color or spectral response of the eye and a typical copying process in percentages to light wavelengths measured in millimicrons under conditions of uniform, illumination over the spectrum.
  • Curve A identifies the color response of the eye
  • curve B represents the transmission of light of the orange filter
  • curve A the transmission of light of the neutral optical attenuator or gray filter
  • curve D identifies the typical color response characteristics of a conventional copying process
  • curve E designates the composite reflectance of the orange and neutral gray filters or the percentage of the incident light which is reflected from a white substrate covered with the orange and neutral gray filters.
  • This latter curve represents the reflected light which reaches the detector or sensitized area of the copying process and, of course, the eye when the document is being read.
  • the portion of this light which is effective in the copy process is that which is within the spectral response of the machine, or within the shaded area shown in FIG. 1.
  • only that portion of this light which is within the spectral response of the eye will be effective in the reading process. From an inspection of the graph of FIG. 1, it is seen that the color of the filter can be modified and the density of the neutral density filter can modified in such a manner so that their combined effect on an original document will minimize the useful light reflected in the copy process but maximize readability of the original.
  • filters can be provided in the form of films laminated or otherwise fixedly secured to the original, or only applied to isolated areas thereon, as desired.
  • pigments, dyes, or coatings formed in or on the background sheet of material prior to imprinting the graphical information thereon can be used in lieu of the above described filters and films, if desired, within the pur view of this invention.
  • a third form of this invention is to imprint the graphical information at several gray levels on a background of uniform contrast to generate confusion or errors in the copy reproduced therefrom.
  • the human eye has excellent gray-scale resolution; i.e., it can differentiate between a multiplicity of shades of gray, ranging from white to black.
  • Light responsive copying machines generally reproduce all of the lighter shades of gray on one side of a selected median as white, and the darker shades on the other side of such median as black.
  • the median shade or white-black transition point can usually be shifted by adjusting the exposure so that the machine sometimes can produce a copy of greater contrast than the original. This gray scale characteristic can be utilized to generate confusion in the copy which is not as apparent in the original.
  • a character such as the letter E" for example can be formed on the original with varying gray scale characteristics. say from dark at the top of the letter to light at the bottom thereof.
  • This letter would be reproduced in the copy as a solid black E or as an F, depend ing upon the contrast setting of the machine.
  • the machine In order to avoid error, the machine would require adjustment to maximum exposure.
  • very fine black lines on a white background would not reproduce due to the overexposure produced by the white background.
  • fine print would be diluted or washed out whereas the heavy letters would reproduce correctly.
  • the heavy print would be erroneously reproduced.
  • Another variation of this form of the invention includes the preprinting of the background material with words, shapes, or forms forming barely perceptible graphics thereon to form a composite background for a document intended to produce confusion with the graphical information imprinted on the preprinted or composite background.
  • the graphical information creates a visual image sufficiently contrasted from the preprinted graphics to be readily distinguished therefrom by the human eye but of insufficient contrast to produce a useful image in a copying machine so that reproduction of the image produces an unintelligible copy.
  • a white background preprinted with light gray graphics and then imprinted with graphical information as describedabove to force the machine to operate at maximum contrast would cause the background confusion patterns or graphics to reproduce as dense or as black as the graphical information, thus leading to confusion and unintelligibility.
  • Still another variation of this form of invention includes the printing of black, low-contrast graphical information and white, high-contrast graphical information on a low-contrast background so that when copied in a typical copying machine, either the low-contrast black graphical information, or the high-contrast white graphical information would reproduce, depending upon the exposure setting of the copying machine. I have found that an original with a red background imprinted with both black and white graphical information cannot be reproduced as an intelligent copy at any one condition of exposure.
  • this form of the invention is not restricted to black, white and intermediate scales of gray shading, but can include combinations of any colors which are sufficiently contrasted to the original to permit the readability thereof but which will reproduce as black or shades of gray when prolongedd through conventional copying machines.
  • Still another form of this invention for producing copy resistant documents is to provide obliterating or interference patterns on the original document that are related to the angle at which the document is viewed.
  • a manuscript or document is read at some angle away from the plane perpendicuiar to the printed document and generally, at an angle, ranging approximately from 50 to 70 to the plane of the document.
  • the typical copying machine incorporates optics for viewing the document perpendicularly thereto because viewing at an angle tends to distort and pre vent accurate focusing on the graphical information imprinted on the document by the copying machine optics, thereby producing a poor copy. Referring now to FIG.
  • a film 10 of transparent material is provided with a series of parallel and equally spaced opaque planes 12 disposed at angles of from 50 to 70, and preferably 60 to the horizontal.
  • Film 10 is placed over an original document 14 and can be adhesively or otherwise fixedly secured thereto.
  • These opaque planes 12 may be black or reflective. and extend from the top surface of film 10 to the bottom surface thereof and serve as blinds" or shutters.
  • planes 12 appear only as end lines and offer no significant impairment to readability.
  • Film 10 can be formed of any suitable transpar ent plastic material as a sheet having a thickness of about 0.002 inches.
  • the opaque planes 12 being approximately 0.000l of an inch thick and spaced at 0.00] inch intervals. It should be understood that the above dimensions are illustrative only and that they may vary widely. as desired, within the purview of this invention.
  • FIG. 3 Another variation of this form of the invention is the use of an overlay in the form of a transparent plastic film 16 having a serrated upper surface or sawtooth formation as shown in the exaggerated view of FIG. 3.
  • the serrated formation comprises a plurality of uniformly spaced, triangularly shaped teeth 18, projecting upwardly from a base 20.
  • Each tooth 18 is provided with a generally vertical surface 22 and an inclined or slop ing surface 24 converging toward surface 22 and meeting therewith at a crest portion 26.
  • Film 16 is formed of a suitable transparent plastic material as a sheet hav ing a base thickness of about 0.001 inches. Teeth 18 are spaced at approximately 0.001 inch intervals and have a depth of about 0.002 inches.
  • Sloping surfaces 24 can be either black or re flective. as indicated by the heavy lines on surfaces 24.
  • the image sensed is a solid surface completely masking the graphical information on the document 28.
  • document 28 is easily readable.
  • Still another variation embraced by this obliterating or interference pattern concept is the provision of means in a transparent film overlying a document for effecting total internal reflectance of light passing through the film in a direction substantially perpendic ular to the plane of the film.
  • a transparent. plastic film 16' overlying document 28' is provided with an internal serrated formation 30 inter posed between the upper and lower surfaces of film 16 and separates the latter into an upper region 32 and a lower region 34, the region 32 being formed of a material having a higher optical index of refraction than the material of region 34.
  • Serrated formation 30 consists of a plurality of uniformly spaced, triangularly shaped teeth 36 extending transversely of film 16.
  • each tooth 36 having a pair of sloping surfaces 38 and 40 converging toward each other and forming angles 6 and 6;, with l a horizontal plane cut through film 16.
  • Light rays extending in the direction of arrows C. C and C are striking the upper surface of film 16 at incident angles perpendicularly or substantially perpendicularly thereto, or within a range of angles between C and C will impinge against surface 40 and be reflected thereby onto surface 38 of the adjacent tooth 36, and then be reflected from the latter outwardly through the upper surface of film 16' to undergo complete or total internal reflectance.
  • the graphical information on document 28 cannot be seen and is com pletely obliterated when viewing such document from a direction substantially normal to the plane thereof, as in the conventional copying machine.
  • the graphical information on document 28 can be easily read.
  • the limits defining the angles of incidence that will undergo total internal reflectance are dictated by the combination of materials of different refractive indices and the sizes of angles 9, and H
  • the material forming region 34 can be a suitable transparent adhesive securing the material of region 32 to document 28 or region 34 can be a transparent plastic material formed integral with the material of region 32 as a composite film secured to document 28' by a separate adhesive means.
  • FIG. 5 A further embodiment of this variation is shown in FIG. 5 and comprises a transparent, plastic film 16" adapted to overlie a document 28" and provided with a serrated lower surface or sawtooth formation consisting of a plurality of uniformly spaced, triangularly shaped teeth 42 projecting downwardly from an upper base 44.
  • Each tooth 42 is provided with a pair of in clined or sloping surfaces 46 and 48 converging toward each other and meeting at a crest portion 50, surfaces 46 and 48 forming angles 6', and 6' with a horizontal plane cut through film 16''.
  • These crest portions 50 of teeth 42 engage the upper surface of document 28" in the assembled relation.
  • a background sheet of material 52 preferably formed of a base colored paper, such as orange for example, is provided with a substrate 54 having a plurality of uniformly spaced, triangularly shaped teeth 56 projecting upwardly from substrate 54 and extending crosswise thereof.
  • Each tooth 56 includes a generally vertically extending surface 58 and an inclined sloping surface 60 extending upwardly at an angle in converging relation with surface 58 and meeting therewith at an apex on crest 62.
  • a typical sheet 52 may have an overall thickness of 0.0025 inches with teeth 56 spaced at 0.001 inch intervals and the inked portion of the cavities therebetween having a width of approximately 0.0005 inches, or approximately onehalf the spacing between the crests of adjacent teeth 56.
  • sheet 52 when sheet 52 is viewed from a direction normal to the plane thereof, it will appear as 50% black and 50% orange depicting alternating black and orange, strips of substantially equal widths.
  • sheet 52 When viewed from a convenient reading angle generally normal to sloping surface 60, or from the direction indicated by arrows E in FIG. 7, sheet 52 will display a substantially completely orange color.
  • Graphical information imprinted on the sloping sur faces 60 of the embossed or serrated surface of sheet 52 will produce a document easily read at a slight angle relative to the plane of such document, or in the direction of arrows E in FIG. 7, because the background for such graphical information is of a relatively higher reflectance.
  • the background displayed is 50% black to effect a reduction in contrast between the background and the graphical information to an unacceptable low level thereby causing such copying machines to produce unsatisfactory copies.
  • FIG. 8 illustrates a modified sawtooth pattern embossed in the top surface of a sheet of material 68 comprising a substrate 70 having a plurality of spaced apart teeth 72 projecting upwardly therefrom and extending transversely thereof. Teeth 72 are of a lesser height than teeth 56 and define arcuately shaped cavities 74 between the lower ends thereof. Cavities 74 are partially filled with black ink 76. as shown in FIG. 8, to cover approximately 50% of sheet 68 when viewed perpendicularly to the plane thereof in the same manner and for the same purpose described above in connection with the embodiment of HO. 7.
  • Still another variation contemplated by this form of the invention is to treat the top surface of the background sheet upon which graphical information is to be imprinted in such a manner as to develop surface irregularities thereon having a very fine grain provided with a surface reflectance which is dependent on the view ing angle.
  • the upper printing sur face of a background sheet of material 78 is roughened to produce a nap 80 consisting of a multiplicity of fibers extending upwardly from sheet 78 and generally oriented at an angle relative to the plane of sheet 78.
  • This roughened condition can be generated by conventional embossing techniques, by simply abrading or brushing the upper surface of sheet 78 in one direction by a suitable tool, or any other suitable process.
  • the upper surface of sheet 78 is coated by directing a spray of an orange colored pigment or dye, for exam ple, on sheet 78 at an angle, or in the direction of ar rows F, generally corresponding to the angle at which sheet 78 would be viewed for reading.
  • the orange colored material deposited on nap 80 of sheet 78 which is of a different color from the pigment or dye, such as a black or dark color for example, causes the document to appear completely orange when viewed along the spray axis or in the direction of arrows F. When viewed normal to the plane of sheet 78, the latter appears as a mixture of orange and black.
  • Grapical information imprinted on the surface irregularities forms a document readable at typical human eye viewing angles but creating a poor image for reproduction by a copying machine which views the document perpendicularly to the plane of the latter.
  • the graphical information ap plied to sheet 78 preferably should be of the same re flectance characteristics as sheet 78 to achieve maximum degradation of the copy produced by a conventional copying process.
  • a further variation contemplated by this form of the present invention is to imprint only portions of each letter or character of the graphical information on the base sheet of the original document with the remaining portions of such letters and characters being imprinted on the top side of a transparent film overlying the base sheet and slightly offset therefrom to render the composite graphical information on the document readable when viewed at an angle approximately 60 to the plane of such document.
  • the letters and characters forming the composite graphical infor mation perceived by such optics and transferred to the copy are unintelligible.
  • Still another variation contemplated by this form of the invention employs the use of minute, solid globules of a colored pigment deposited on the surface of a low reflectance background material to form a composite background for graphical information to be imprinted thereon.
  • background material When such background material is viewed perpendicular to its surface, it will have a composite reflectance depending upon the ratio of the area covered by the pigment globules to the total area.
  • the composite reflectance will be the ratio of the area covered by the pigment globules to the total projected area at that angle.
  • a document generally designated 82, comprising a background sheet of material 84, preferably of a low-reflectance color, such as black for example, having a multiplicity of minute globules 86 of an orange pigment disposed on the top surface of sheet 84.
  • Globules 86 which are sprayed on sheet 84, are of varying sizes and shapes and are irregularly or randomly oriented relative to each other. The specific size of each globule 86, which may on the order of 0.001 inches in diameter for example, is not critical so long as it is very small relative to the size of the graphi cal information detail imprinted on sheet 84.
  • sheet 84 When document 82 is viewed perpendicularly to the plane thereof. sheet 84 appears as a mixture of black and orange. however, when viewed at some angle less than 90 to the plane of document 82, such as in the direction of arrows G in FlG. ll, sheet 84 will appear more orange than black. the proportion of orange perceived being dictated by the specific viewing angle and the shape and spacing of globules 86.
  • Graphical informa tion imprinted on background sheet 84 preferably should be of the same reflectance characteristics. with respect to color and density, as sheet 84 on which the orange pigment globules 86 have been applied to achieve maximum degradation of the copy produced by a conventional copying process. I have found that documents prepared in the manner set forth above are effective to defeat virtually all known copying ma chines.
  • the basic stock material used was a full black paper of any suitable weight having a reflectance of less than at wavelengths from approximately 300 to 1000 mu.
  • This basic stock material was spray coated with an orange/red ink having a reflectance at wave lengths of 575 mu and an 80% reflectance at wavelengths of 625 mu, such that the total reflectance of the coated sheet did not exceed 40% at wavelengths of 650 mu.
  • FIG. 12 graphically illustrates the combined effect of an orange-red ink sprayed on a black substrate on a graph which correlates the spectral or reflective response of the eye and a typical copying process in percentages to light wavelengths measured in millimicrons under conditions of uniform illumination over the spectrum.
  • Curve X identifies the response of the eye; curve Y the response of a typical copying system; and curve Z represents the combined reflectance of a coating of orange-red pigment on a black surbstrate or background.
  • the shaded area between curves Y and Z represent the reflected light which reaches the detector or sensitized region of the copying system. From an m spection of the scale of FIG. 12 it can be determined that the background curve Z has a spectral response of substantially 4% over the wavelength range of substan tially 325 to 525 millimicrons which increases from substantially 7% at substantially 550 millimicrons to substantially 13% at the point where curves Y and Z intersect corresponding to about 575 millimicrons.
  • the orange-red ink was sprayed in such a manner as to form minute globules on the basic black background whereby the sheet appeared more orange when viewed at an angle slightly less than to the plane of the sheet than when viewed normal to the surface of the sheet.
  • This coated sheet was then oversprayed with a thin film of varnish or lacquer to preclude the black graphical information. subsequently applied to such sheet, from diffusing into the orange/red background and to minimize the surface scattering, particularly in the spectral region of low reflectivity.
  • This composite sheet can be used as an original in conventional typewriters or in any printing process using conventional black ink, or as feed stock to a copying machine to produce non-reproducible copies from the copyable original.
  • the black graphical information imprinted on the composite orange/red background offered sufficient contrast to render the document easily readable by the human eye at typical viewing angles but of insufficient contrast to produce a useful image in a copying machine whereby a copy produced by the lat ter was unintelligible.
  • portions or areas selected to be copy resistant or non reproducable by conventional copying machines can be artistically treated so as to form an aesthetic or pleasing background for the graphical information imprinted thereon. For example, a corporate insignia, a trademark, or other identifying symbols can be employed as the background pattern in these selected portions.
  • EXAMPLE A dense, gray-black ink was spray coated along the opposite sides and bottom marginal edges of a sheet of white paper to form a relatively dark border therealong about l.5 inches wide. The ink was sprayed inwardly of this border at progressively lighter shades to form a ta' pering ligher background inwardly of the border and terminating in a white background centrally of the document. This sheet was oversprayed with an orange/red ink to form minute globules thereon similarly to that disclosed in the first Example, except that the reflectance at the center of the sheet was maintained as large as desired while the reflectance along the black border was maintained below 30%. A suitable lacquer or var nish may be sprayed over the multicolored original, as desired.
  • Black graphical information was imprinted on the multi-colored sheet to form a document which was processed through a conventional copying machine. While readability of the original was satisfactory, the intelligibility of the copy produced by the copying machine was low because the graphical information along the darkened border was unreadable. The copy produced depicted a clear intelligible central portion but an obliterated marginal edge portion. As previously mentioned, it was only necessary to obliterate portions of the graphical information of the copy to render it worthless. The obliteration of certain Words, sentences, or one marginal edge of the graphical information on the copy generally would defeat its utility. However, top security original documents and those of an extreme sensitive nature should be entirely treated to render them completely uncopyable to preclude any possibility of deciphering copies made therefrom.
  • Still another form of this invention for producing copy resistant documents in the utilization of photochromic, phototropic or photothermic materials, which change their optical properties such as color and/or op tical density when subjected to changes in light or heat, respectively.
  • photochromic, phototropic or photothermic materials which change their optical properties such as color and/or op tical density when subjected to changes in light or heat, respectively.
  • These materials can be used as dyes, pigments, inks, films or papers to modify the contrast between the background sheet and the graphical information imprinted thereon under changing conditions of light and heat.
  • These materials may be used in an almost infinite variety of combinations to effect a change in either color or density contrast to impair the reproduction of an original document by various known copying machines.
  • a photochromic orange dye is employed as the background color upon which is imprinted black graphical information.
  • photochromic, phototropic or photothermic materials can be in the form of a dye added to the base stock paper material to form the background thereof, as a coating on the paper stock, as a printing ink, or as a film to be applied to the paper stock after the graphical information has been imprinted thereon.
  • photochromic as used herein is intended to include any and all materials which undergo a change in their optical properties, such as color and/or optical density when subjected to changes in light intensity and embraces materials which undergo a permanent change of color, those that revert back to their original color, or those that may require a different stimulus in order to revert back to their normal or inactivated state.
  • a photochromic material for this application should respond to. or be activated by, the radiation present in the illumination source of the copying machine and should not be activated by those elements of the radiation spectrum of the sun and artificial illumination not present in the copy machine so as to prevent or minimize the change of the contrast of the document under normal viewing conditions.
  • the illumination sources in copy machines have a very low percentage of their radiation in the ultraviolet portion of the spectrum, whereas sunlight is strong in ultraviolet and the predominance of photochromic materials studied to date are activated in the ultraviolet region and show a color or density change in the visible portion of the spectrum.
  • most photochromic materials, by design do not change their absorption or reflection properties at their excitation wavelengths; hence, the longer they are exposed, the greater the color Change to be expected.
  • the spectral change is the product of the intensity of the illumination at the excitataion wavelength and time, or until the entire photochromic materials has converted, as the limit.
  • the photochromic material should be excited in the visible or infra red portion of the spectrum and should darken" or react at the excitation wavelength as well as elsewhere in the spectrum, such that the material arrives at a photo-stable condition as a function of the light intensity and will not go to total conversion with long time exposure at low levels of illumination.
  • the dithizonates and the heavy metal complexes of dithizone are excellent examples of a class of suitable photochromic materials.
  • a solution of mercury bisdithizonate which is orange in its unexcited state and shifts to blue upon excitation by radiation which includes blue, can be applied as a thin, transparent coating on orange paper.
  • the film Under normal illumination, the film remains orange with a slight shift to the yellow and readibility is not impaired.
  • the film With increasing illumina tion, as in a copy machine, the film shifts to the blue. This blue filter in combination with the orange background appears almost black, thus reducing the contrast between the background and the graphical information printed thereon to a very low level.
  • the graphical information can be printed with an opaque orange photochromic ink, produced for example, from a dithizonate and which darkens to a gray-brown upon high intensity irradiation in the visible portion of the spectrum to degrade the copy produced by a light activated copying machine.
  • dithizonates and heavy metal complexes of dithizone are preferably used as the photochromic materials in the above examples because of their sensitivity in the visible portion of the spectrum and their rapid responses to varying illumination, it should be understood that this invention is in no manner limited to the use of such dithizonates but can employ any suitable photochromic materials within the purview of this invention.
  • a still further form of this invention utilizes ultra violet and infra red absorbing materials, such as those offered by the American Cyanamil Corp. of Boundbrook, N.J., which are transparent in the visible spectrum and which can be added to the background materials, the film or the inks
  • ultra violet and infra red absorbing materials such as those offered by the American Cyanamil Corp. of Boundbrook, N.J., which are transparent in the visible spectrum and which can be added to the background materials, the film or the inks
  • ultra violet and infra red absorbing materi may be included in the photochromic orange pigment applied to the substrate in the example previously described Indeed.
  • the present in vention fully accomplishes its intended objects and provides methods for treating or producing original docu ments in such a manner as to at least inhibit the production of intelligible copies therefrom by conventional copying machines.
  • the sheet of material according to claim 1 wherein said portion is a dark orange 3.
  • the sheet of material according to claim 2 further comprising graphical information on said sheet of ma terial having an average reflectance closer in value to 7% than 13% at all wavelengths 4.
  • the sheet of material according to claim 3 wherein the reflectance of said graphical information is substantially 5% S.
  • the sheet of material according to claim 1 further comprising graphical information on said sheet of material having an average reflectance closer in value to 7% than 13% at all wavelengths.

Abstract

Methods for treating or producing original documents to inhibit, if not preclude, the reproduction of such documents by copying processes. The documents so produced favor the visual response of the human eye over the physical response of a copying machine so that the graphical information imprinted on the document background is readily perceptible by the human eye but imperceptible by the sensor and associated processes of a copying machine.

Description

United States Patent Reinnagel June 3, 1975 [54] COPY RESISTANT DOCUMENTS 3,001,857 9/1961 Ahlm 6i a]. 117/1 [76] Inventor: Richard E. Reinnagel, 60 East Jerge 167L451 6/1972 utterfield Dr 131,11 ,10 14059 FOREIGN PATENTS OR APPLICATIONS 757,519 4/1967 Canada ll7/l [22] 1972 402,028 11/1933 United Kingdom 283/8 R [21] APPL 243,743 198,364 4/1924 United Kingdom 117/1 Primary Examiner-William R. Trenor Methods for treating or producing original documents to inhibit, if not preclude, the reproduction of such documents by copying processes. The documents so produced favor the visual response of the human eye over the physical response of a copying machine so that the graphical information imprinted on the document background is readily perceptible by the human eye but imperceptible by the sensor and associated 6 Claims, 12 Drawing Figures 2Z- O'RANGE-RED N BLACK [52 US. Cl 428/211; 283/8 R; 350/160 R; A A t J J ff 350/162 R; 350/162 SF; 350/163; 350/164; Omey gen or a 6 428/913; 428/916 [51 Int. Cl...... 842d /00; 844d 1/44; D21h 5/10 [57] ABSTRACT [58] Field of Search 117/1, 283/8 R; 355/133, 3 R,9, 17; 350/162 R, 162 SF, 163, 164, 160 R [56] References Cited UNITED STATES PATENTS 690,l48 l2/l90l Hissins ll7/l 2,936,247 5/1960 Francis etal. 2,952,080 9/1960 Higgins 35/2 processesofacopymg machme' 2,992,121 7/1961 Francis et al 106/23 l T i i i x- EYE RESPONSE 80 l w Y-COPYlNG in 60 PROCESS z E m 4-0 m u:
0 IJJIIJI(,;IIIIIIIIIII/I,II/
IN MILLlMlCRONS PATENTED 3 I975 "/0 RESPONSE Y-COPYIN G PROCESS D 0N BLACK WAVELENGTH 1N MILLIMI R NS COPY RESISTANT DOCUMENTS BACKGROUND OF THE INVENTION This invention relates generally to the production of documents and the like having copy resistant characteristics and, more particularly, to copy resistant documents and to methods for treating or producing original documents in such a manner so as to yield easily readable documents under normal reading conditions but inhibiting, if not preventing, the reproduction of intelligible copies thereof by conventional copying processes.
Copying machines have become increasingly popular in recent years and can be found in most business of fices and in public areas, such as shopping centers, hotel lobbies and the like. Because of the widespread availability of various types of copying machines, the ease with which they can be operated, and the low cost of each copy, virtually all documents are susceptible to be copied to anyone without the consent of the originator or owner While the development of these copying machines certainly represents progress in the graphical communication field, they are often used to copy documents which maybe abusive to the originator or owner. For example, the unauthorized and indiscriminate copying of materials such as news letters, poems, sheet music, drawings etc, may violate the legal rights of the publishers and/or authors denying to them the compen sation to which they are entitled. Also, security can be flagrantly breached by copying material of a sensitive nature such as classified government information, industrial and commercial data. and personal correspondence of a confidential nature.
SUMMARY OF THE INVENTION Accordingly, it is a primary object of the present invention to provide copy resistant documents and meth ods for producing or treating original documents so as to inhibit, if not prevent, the reproduction thereof by conventional copying machines and processes.
It is another object of this invention to provide original documents which favor the spectral response of the human eye over the spectral response of a conventional copying process.
It is another object of the present invention to pro vide improved color contrast between an original document background and the graphical information imprinted thereon which is readily distinguishable by the human eye but poorly discernible by the sensor of a copying machine.
It is still another object of this invention to provide density or reflectance contrast between an original document background and the graphical information imprinted thereon which is readily distinguishable by the human eye but poorly discernible by the sensor of a copying machine.
It is another object of the present invention to provide multi-contrast density or reflectance printing on an original document background to generate confusion in the copies reproduced by a conventional copying process.
It is yet another object of this invention to provide a method of producing obliterating patterns in the view ing path of the original document that are related to the angle of viewing.
It is a further object of the present invention to provide a color or reflectance contrast between an original document and the graphical information imprinted thereon which is related to the angle of viewing the document.
It is still a further object of this invention to form either the original document background. or the graphical information imprinted thereon, or a film overlying the document, from photochromic, phototropic and photothermic materials which affect the contrast be tween the background and the graphical information under varying conditions of light and heat.
It is yet a further object of the present invention to employ any one, or any combination of the foregoing methods, to produce a document having varying degrees of copy resistance.
The foregoing and the other objects, advantages, and characterizing features of the present invention will become clearly apparent from the ensuing detailed description thereof, taken together with the accompanying drawings wherein like reference characters denote like parts throughout the various views.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. is a diagrammatic view illustrating the effects of color and low reflectance filters on a graph which correlates the color or spectral response of the human eye and a copying machine in percentages to wavelengths of light in millimicrons;
FIG. 2 is a fragmentary, perspective, exaggerated view of a copy resistant document constructed in accordance with one form of this invention;
FIG. 3 is a fragmentary side elevational view, on a greatly enlarged scale, of another form of a copy resistant document of this invention;
FIG. 4 is a fragmentary side elevational view, greatly enlarged, of still another form of a copy resistant document of the present invention:
FIG. 5 is a fragmentary side elevational view, greatly exaggerated, of another embodiment of the form of copy resistant document shown in FIG. 4;
FIG. 6 is a fragmentary, perspective, exaggerated view of still another form of a copy resistant document of this invention;
FIG. 7 is a fragmentary side elevational view, on a greatly enlarged scale, of the document shown in FIG.
FIG. 8 is a view similar to FIG. 7 illustrating another embodiment of the form of this invention shown in FIG. 7;
FIG. 9 is a fragmentary side elevational view, greatly exaggerated, illustrating still another embodiment of a copy resistant document constructed in accordance with the present invention;
FIG. 10 is an exaggerated fragmentary plan view of yet another form of copy resistant document of this invention;
FIG, 11 is a fragmentary side elevational view, of the document shown in FIG. I0; and
FIG. 12 is a diagrammatic view similar to FIG. 1 illustrating a graph which correlates the color or spectral responses of the human eye and :1 copying machine in percentages to wavelengths of light in millimicrons.
DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS While the known copying processes and machines utilize widely different principles of operation, they are all dependant upon an inherent or induced contrast between the background sheet material of a document and the graphical information imprinted thereon for the development of an image on a sensitized surface on, or from which, the copy is produced. The expression graphical information" as used herein includes words, letters, numerals, drawings. graphics, etc. or any indicia that can be imprinted on a background sheet of material. The required contrast can be in the form of a color difference between two colors of the same density or reflectance, or a reflectance contrast between two shades of a given color, such as a light blue color as opposed to a dark blue color, or a combination of both color contrast and reflectance or density contrast, Reflectance or density as used herein is: Log l (Incident light)/(Reflected light). Reflectance can also be ex pressed as the percentage of the incident light that is reflected. The spectral or color sensitivity of these known copying machines do not match the sensitivity and density range of the human eye.
Density range is conveniently referred to as the range of values of reflectance over which the eye can recognize a change in reflectance. The eye may not recognize a slight change in reflectance when the reflectance is near 100% as in white, or 0% as in black. The eye tends to have a linear response to changes in density between 0.05 and 1.05, corresponding to a reflectance of 90% and 8%, respectively. Copying processes generally have a much smaller dynamic range than the eye, such as 0.3 to 0.6. and this density range can generally be moved between the limits of 0.05 and l.(] by an adjustment of the exposure control on the machine. The limited dynamic range of these copying processes tends to produce a black and white copy with poorer gray scale than in the original.
The principles of this invention contemplate a multiplicity of techniques. which can be used singly or in combination, to treat an original document in such a manner as to affect the color and/or reflectance or density contrast between the background and the graphical information to maintain the original easily readable, or to render the document readable at certain viewing angles, but to adversely affect the image reproduced by the copying machine to produce a copy which is unintelligible or at least less intelligible than the original document. Stating this another way, the original is treated so as to favor the responses of the human eye but inhibit the responses of copying machines to prevent the production of a usable copy. It should be appreciated that the degree of copy resistance imparted to the original is generally dictated by the sensitivity of the material disclosed in the document, and, since any document can be manually copied, the extent of copy resistance need only be sufficient to render automatic or direct copying by means of copying machines at least as expensive and more complicated than manual copying. The term original as used herein is intended to embrace any document to be copied, whether it be the true original or a copy or reproduction thereof.
It should be understood that the methods, hereinafter described in detail, are generally combined to produce documents capable of resisting reproduction by the various known copying machines and the selection of a particular method, or combination of methods, will be dictated by the specific copying machines intended to be defeated as well as by the degree of copy resistance desired and the acceptable degradation in read ability. Also, it must be realized that the copying machine operator can modify the machine in an effort to overcome the resistance to copying imparted to the document by the methods of this invention by adjusting the exposure control for better contrast and/or by superimposing a filter on the original to modify any color contrast between the background and the graphical information imprinted thereon. Thus, the method or combination of methods selected must provide the desired level of copy resistance when such simple opera tor actions are taken.
In accordance with this invention, one method employed to favor the spectral response of the human eye over the spectral response of the copying machine is in the selection of different colors or color filters. The choice of a color or colored filter should be based upon the spectral sensitivity or color response of known copying machines and the human eye and optimized to obtain the least loss in contrast and reading comfort while yielding a maximum in color contrast reduction at the copying machine receptor, with due consideration given to the spectral characteristics of the source of illumination for both the copy machine and the human eye. I have found, through experimentation with various colors within the total visual spectrum that a warm or dark orange background having black graphical information imprinted thereon produces a very comfortable and pleasing background for the black graphical information. This orange color materially re duces the capability of most copying machines to produce a readable copy and requires the machine to be adjusted to maximum exposure. The color can be applied to the paper stock as a dye or as a coating before the graphical information is printed on the background.
I have also found, through experimentation with vari ous colored filters of equal attenuation, that a warm or dark orange filter overlying an original document having a white background and black graphical information imprinted thereon effects a pleasing background for the black graphical information. Indeed, such an overlay produces a document as easily read as the origi nal but materially reduces the capability of most copying machines to produce a readable copy. The filter can be provided in the form of a film of a transparent colored plastic material or of a clear plastic material provided with a colored adhesive and applied to the document to be protected by any suitable or conventional laminating process, or the film can be produced as a pressure sensitive tape adapted to be applied from a roll to cover the entire surface of the document, or only isolated areas thereof, as desired. In business offices, the film could be dispensed from a specially designed machine attached to the office copying machine and applied to the copies reproduced from the original so as to prevent such copies from being further copied by the various known copying systems.
Another form of this invention is the utilization of low reflectance backgrounds with low reflectance graphical information imprinted thereon. It is known that dark or deep colors reflect less light than bright or light colors. Thus, dark or low reflectance graphical information disposed on a low reflectance background reflects less of the incident light and therefore less energy to the sensor or image forming surface in lightactivated copying machines. When low reflectance or dark backgrounds are used with low reflectance graphical information, the copying process must usually be adjusted to operate at maximum exposure to yield a useful copy, if indeed a copy can be made. I have found that gray background density of 0.4, when used with printing inks of densities above 1, will produce marginally readable copies when the copy machine is operated at the maximum exposure condition. However, the originals so produced are very comfortable and easy to read.
Through the use of a background material which incorporates both selective color or spectral response and low reflectance, an optimum combination can be selected to yield a document which is easily read, yet difficult to impossible to copy. To this end, I have found that the combination of a warm orange filter and a neutral optical attenuator, such as a neutral gray filter, which transmits approximately 50% of the inci dent light, used as an overlay on white paper with black printing, effects a sufficient reduction in contrast to defeat virtually all of the known copying systems.
FIG. 1 graphically illustrates the effect of the combi nation of a color filter and a low reflectance filter on a graph which correlates the color or spectral response of the eye and a typical copying process in percentages to light wavelengths measured in millimicrons under conditions of uniform, illumination over the spectrum. Curve A identifies the color response of the eye; curve B represents the transmission of light of the orange filter; curve A the transmission of light of the neutral optical attenuator or gray filter; curve D identifies the typical color response characteristics of a conventional copying process; and curve E designates the composite reflectance of the orange and neutral gray filters or the percentage of the incident light which is reflected from a white substrate covered with the orange and neutral gray filters. This latter curve represents the reflected light which reaches the detector or sensitized area of the copying process and, of course, the eye when the document is being read. The portion of this light which is effective in the copy process is that which is within the spectral response of the machine, or within the shaded area shown in FIG. 1. Similarly, only that portion of this light which is within the spectral response of the eye will be effective in the reading process. From an inspection of the graph of FIG. 1, it is seen that the color of the filter can be modified and the density of the neutral density filter can modified in such a manner so that their combined effect on an original document will minimize the useful light reflected in the copy process but maximize readability of the original. Again these filters can be provided in the form of films laminated or otherwise fixedly secured to the original, or only applied to isolated areas thereon, as desired. Also, pigments, dyes, or coatings formed in or on the background sheet of material prior to imprinting the graphical information thereon can be used in lieu of the above described filters and films, if desired, within the pur view of this invention.
A third form of this invention is to imprint the graphical information at several gray levels on a background of uniform contrast to generate confusion or errors in the copy reproduced therefrom. The human eye has excellent gray-scale resolution; i.e., it can differentiate between a multiplicity of shades of gray, ranging from white to black. Light responsive copying machines generally reproduce all of the lighter shades of gray on one side of a selected median as white, and the darker shades on the other side of such median as black. The median shade or white-black transition point can usually be shifted by adjusting the exposure so that the machine sometimes can produce a copy of greater contrast than the original. This gray scale characteristic can be utilized to generate confusion in the copy which is not as apparent in the original.
To illustrate one aspect of this confusion generation concept, a character such as the letter E" for example can be formed on the original with varying gray scale characteristics. say from dark at the top of the letter to light at the bottom thereof. This letter would be reproduced in the copy as a solid black E or as an F, depend ing upon the contrast setting of the machine. In order to avoid error, the machine would require adjustment to maximum exposure. However, when operating the machine at maximum exposure, very fine black lines on a white background would not reproduce due to the overexposure produced by the white background. Hence, fine print would be diluted or washed out whereas the heavy letters would reproduce correctly. Conversely, at an exposure which is correct for the fine print, the heavy print would be erroneously reproduced.
Another variation of this form of the invention includes the preprinting of the background material with words, shapes, or forms forming barely perceptible graphics thereon to form a composite background for a document intended to produce confusion with the graphical information imprinted on the preprinted or composite background. The graphical information creates a visual image sufficiently contrasted from the preprinted graphics to be readily distinguished therefrom by the human eye but of insufficient contrast to produce a useful image in a copying machine so that reproduction of the image produces an unintelligible copy. A white background preprinted with light gray graphics and then imprinted with graphical information as describedabove to force the machine to operate at maximum contrast would cause the background confusion patterns or graphics to reproduce as dense or as black as the graphical information, thus leading to confusion and unintelligibility.
Still another variation of this form of invention includes the printing of black, low-contrast graphical information and white, high-contrast graphical information on a low-contrast background so that when copied in a typical copying machine, either the low-contrast black graphical information, or the high-contrast white graphical information would reproduce, depending upon the exposure setting of the copying machine. I have found that an original with a red background imprinted with both black and white graphical information cannot be reproduced as an intelligent copy at any one condition of exposure.
The above illustrations are exemplary only and it should be understood that variations of this form of the invention are contemplated which employ specially prepared backgrounds having graphical information imprinted thereon varying over a wide range of reflectances and combinations of reflectances in the details of the individual characters of such graphical information which are beyond the range of contrast recognition and resolution of a conventional copying machine at any one exposure setting thereof. Also, this form of the invention is not restricted to black, white and intermediate scales of gray shading, but can include combinations of any colors which are sufficiently contrasted to the original to permit the readability thereof but which will reproduce as black or shades of gray when pro cessed through conventional copying machines.
Still another form of this invention for producing copy resistant documents is to provide obliterating or interference patterns on the original document that are related to the angle at which the document is viewed. Normally. a manuscript or document is read at some angle away from the plane perpendicuiar to the printed document and generally, at an angle, ranging approximately from 50 to 70 to the plane of the document. However. the typical copying machine incorporates optics for viewing the document perpendicularly thereto because viewing at an angle tends to distort and pre vent accurate focusing on the graphical information imprinted on the document by the copying machine optics, thereby producing a poor copy. Referring now to FIG. 2, a film 10 of transparent material is provided with a series of parallel and equally spaced opaque planes 12 disposed at angles of from 50 to 70, and preferably 60 to the horizontal. Film 10 is placed over an original document 14 and can be adhesively or otherwise fixedly secured thereto. These opaque planes 12 may be black or reflective. and extend from the top surface of film 10 to the bottom surface thereof and serve as blinds" or shutters. When document 14 is viewed at an angle of so to the plane thereof. as in normal reading and as indicated by the arrows A in FlG. 2, planes 12 appear only as end lines and offer no significant impairment to readability. However, when docu rnent 14 is viewed perpendicularly to the plane thereof, as by the optical sensor in conventional copying machines, the angularly oriented planes l2 conceal the graphical information on document 14 and appear as a black or reflective surface. thereby causing the machine to produce an obliterated and completely useless copy. Film 10 can be formed of any suitable transpar ent plastic material as a sheet having a thickness of about 0.002 inches. the opaque planes 12 being approximately 0.000l of an inch thick and spaced at 0.00] inch intervals. It should be understood that the above dimensions are illustrative only and that they may vary widely. as desired, within the purview of this invention.
Another variation of this form of the invention is the use of an overlay in the form of a transparent plastic film 16 having a serrated upper surface or sawtooth formation as shown in the exaggerated view of FIG. 3. The serrated formation comprises a plurality of uniformly spaced, triangularly shaped teeth 18, projecting upwardly from a base 20. Each tooth 18 is provided with a generally vertical surface 22 and an inclined or slop ing surface 24 converging toward surface 22 and meeting therewith at a crest portion 26. Film 16 is formed of a suitable transparent plastic material as a sheet hav ing a base thickness of about 0.001 inches. Teeth 18 are spaced at approximately 0.001 inch intervals and have a depth of about 0.002 inches. Again, these di mensions are exemplary only and can vary widely, as desired. Sloping surfaces 24 can be either black or re flective. as indicated by the heavy lines on surfaces 24. when the underlying document 28 is viewed perpendicularly to the plane thereof by the conventional copying machine sensor, the image sensed is a solid surface completely masking the graphical information on the document 28. However, when observed from a convenient viewing angle by the human eye, or in the direc- 8 tion of arrows B in HG. 3. document 28 is easily readable.
Still another variation embraced by this obliterating or interference pattern concept is the provision of means in a transparent film overlying a document for effecting total internal reflectance of light passing through the film in a direction substantially perpendic ular to the plane of the film. As shown in FIG. 4, a transparent. plastic film 16' overlying document 28' is provided with an internal serrated formation 30 inter posed between the upper and lower surfaces of film 16 and separates the latter into an upper region 32 and a lower region 34, the region 32 being formed of a material having a higher optical index of refraction than the material of region 34. Serrated formation 30 consists of a plurality of uniformly spaced, triangularly shaped teeth 36 extending transversely of film 16. each tooth 36 having a pair of sloping surfaces 38 and 40 converging toward each other and forming angles 6 and 6;, with l a horizontal plane cut through film 16. Light rays extending in the direction of arrows C. C and C are striking the upper surface of film 16 at incident angles perpendicularly or substantially perpendicularly thereto, or within a range of angles between C and C will impinge against surface 40 and be reflected thereby onto surface 38 of the adjacent tooth 36, and then be reflected from the latter outwardly through the upper surface of film 16' to undergo complete or total internal reflectance. Accordingly, the graphical information on document 28 cannot be seen and is com pletely obliterated when viewing such document from a direction substantially normal to the plane thereof, as in the conventional copying machine. However, when viewing document 28 from a direction or angle of incidence disposed extcriorly of the limits defined by arrows C and C such those identified by arrows D, D,, and D for example, the graphical information on document 28 can be easily read. The limits defining the angles of incidence that will undergo total internal reflectance are dictated by the combination of materials of different refractive indices and the sizes of angles 9, and H The material forming region 34 can be a suitable transparent adhesive securing the material of region 32 to document 28 or region 34 can be a transparent plastic material formed integral with the material of region 32 as a composite film secured to document 28' by a separate adhesive means.
A further embodiment of this variation is shown in FIG. 5 and comprises a transparent, plastic film 16" adapted to overlie a document 28" and provided with a serrated lower surface or sawtooth formation consisting of a plurality of uniformly spaced, triangularly shaped teeth 42 projecting downwardly from an upper base 44. Each tooth 42 is provided with a pair of in clined or sloping surfaces 46 and 48 converging toward each other and meeting at a crest portion 50, surfaces 46 and 48 forming angles 6', and 6' with a horizontal plane cut through film 16''. These crest portions 50 of teeth 42 engage the upper surface of document 28" in the assembled relation. The spaces or cavities defined by adjacent teeth 42 are filled with air, which has an index of refraction different from that of the material of film 16''. This embodiment is effective in the same manner as the embodiment shown in FIG. 4 for producing total internal reflectance of light passing through film 16" in a direction substantially perpendicular to the plane thereof, as indicated by the arrows C, C, and C' to obliterate the graphical language on document 28". When viewing document 28" from a direction or angle of incidence exteriorly of the limits defined by arrows C and C such as those identified by arrows D, D 'and D the graphical information on document 28" is clearly readable.
Rather than employ a separate film superimposed on a document, the background sheet itself can be embossed in such a manner so as to provide a sawtooth pattern in the top surface thereof. As shown in FIGS. 6 and 7, a background sheet of material 52, preferably formed of a base colored paper, such as orange for example, is provided with a substrate 54 having a plurality of uniformly spaced, triangularly shaped teeth 56 projecting upwardly from substrate 54 and extending crosswise thereof. Each tooth 56 includes a generally vertically extending surface 58 and an inclined sloping surface 60 extending upwardly at an angle in converging relation with surface 58 and meeting therewith at an apex on crest 62. These teeth 56 define cavities 64 therebetween which are partially filled with black ink 66 up to a level approximately midway between the roots and crests of adjacent teeth 56. While not used in a limiting sense, a typical sheet 52 may have an overall thickness of 0.0025 inches with teeth 56 spaced at 0.001 inch intervals and the inked portion of the cavities therebetween having a width of approximately 0.0005 inches, or approximately onehalf the spacing between the crests of adjacent teeth 56. Thus, when sheet 52 is viewed from a direction normal to the plane thereof, it will appear as 50% black and 50% orange depicting alternating black and orange, strips of substantially equal widths. When viewed from a convenient reading angle generally normal to sloping surface 60, or from the direction indicated by arrows E in FIG. 7, sheet 52 will display a substantially completely orange color.
Graphical information imprinted on the sloping sur faces 60 of the embossed or serrated surface of sheet 52 will produce a document easily read at a slight angle relative to the plane of such document, or in the direction of arrows E in FIG. 7, because the background for such graphical information is of a relatively higher reflectance. At a viewing angle normal to the plane of the document, such as are employed in the optics of conventional copying machines, the background displayed is 50% black to effect a reduction in contrast between the background and the graphical information to an unacceptable low level thereby causing such copying machines to produce unsatisfactory copies.
FIG. 8 illustrates a modified sawtooth pattern embossed in the top surface of a sheet of material 68 comprising a substrate 70 having a plurality of spaced apart teeth 72 projecting upwardly therefrom and extending transversely thereof. Teeth 72 are of a lesser height than teeth 56 and define arcuately shaped cavities 74 between the lower ends thereof. Cavities 74 are partially filled with black ink 76. as shown in FIG. 8, to cover approximately 50% of sheet 68 when viewed perpendicularly to the plane thereof in the same manner and for the same purpose described above in connection with the embodiment of HO. 7.
Still another variation contemplated by this form of the invention is to treat the top surface of the background sheet upon which graphical information is to be imprinted in such a manner as to develop surface irregularities thereon having a very fine grain provided with a surface reflectance which is dependent on the view ing angle. As shown in FIG. 9, the upper printing sur face of a background sheet of material 78 is roughened to produce a nap 80 consisting of a multiplicity of fibers extending upwardly from sheet 78 and generally oriented at an angle relative to the plane of sheet 78. This roughened condition can be generated by conventional embossing techniques, by simply abrading or brushing the upper surface of sheet 78 in one direction by a suitable tool, or any other suitable process. In any event, the upper surface of sheet 78 is coated by directing a spray of an orange colored pigment or dye, for exam ple, on sheet 78 at an angle, or in the direction of ar rows F, generally corresponding to the angle at which sheet 78 would be viewed for reading. The orange colored material deposited on nap 80 of sheet 78 which is of a different color from the pigment or dye, such as a black or dark color for example, causes the document to appear completely orange when viewed along the spray axis or in the direction of arrows F. When viewed normal to the plane of sheet 78, the latter appears as a mixture of orange and black. Grapical information imprinted on the surface irregularities forms a document readable at typical human eye viewing angles but creating a poor image for reproduction by a copying machine which views the document perpendicularly to the plane of the latter. The graphical information ap plied to sheet 78 preferably should be of the same re flectance characteristics as sheet 78 to achieve maximum degradation of the copy produced by a conventional copying process.
A further variation contemplated by this form of the present invention is to imprint only portions of each letter or character of the graphical information on the base sheet of the original document with the remaining portions of such letters and characters being imprinted on the top side of a transparent film overlying the base sheet and slightly offset therefrom to render the composite graphical information on the document readable when viewed at an angle approximately 60 to the plane of such document. However, when the document is viewed at an angle of to the plane thereof, as by the optics in conventional copying machines, the letters and characters forming the composite graphical infor mation perceived by such optics and transferred to the copy are unintelligible.
Still another variation contemplated by this form of the invention employs the use of minute, solid globules of a colored pigment deposited on the surface of a low reflectance background material to form a composite background for graphical information to be imprinted thereon. When such background material is viewed perpendicular to its surface, it will have a composite reflectance depending upon the ratio of the area covered by the pigment globules to the total area. When the background material is viewed at an angle of 60 to the plane of the material, as in normal reading, the composite reflectance will be the ratio of the area covered by the pigment globules to the total projected area at that angle.
Referring now to FIG. 10 and 11 to illustrate this concept, there is shown a document, generally designated 82, comprising a background sheet of material 84, preferably of a low-reflectance color, such as black for example, having a multiplicity of minute globules 86 of an orange pigment disposed on the top surface of sheet 84. Globules 86, which are sprayed on sheet 84, are of varying sizes and shapes and are irregularly or randomly oriented relative to each other. The specific size of each globule 86, which may on the order of 0.001 inches in diameter for example, is not critical so long as it is very small relative to the size of the graphi cal information detail imprinted on sheet 84. When document 82 is viewed perpendicularly to the plane thereof. sheet 84 appears as a mixture of black and orange. however, when viewed at some angle less than 90 to the plane of document 82, such as in the direction of arrows G in FlG. ll, sheet 84 will appear more orange than black. the proportion of orange perceived being dictated by the specific viewing angle and the shape and spacing of globules 86. Graphical informa tion imprinted on background sheet 84 preferably should be of the same reflectance characteristics. with respect to color and density, as sheet 84 on which the orange pigment globules 86 have been applied to achieve maximum degradation of the copy produced by a conventional copying process. I have found that documents prepared in the manner set forth above are effective to defeat virtually all known copying ma chines.
The following is cited as an angle of this method in practicing this form of the invention, it being understood that such example is illustrative only and is not used in a limiting sense.
EXAMPLE The basic stock material used was a full black paper of any suitable weight having a reflectance of less than at wavelengths from approximately 300 to 1000 mu. This basic stock material was spray coated with an orange/red ink having a reflectance at wave lengths of 575 mu and an 80% reflectance at wavelengths of 625 mu, such that the total reflectance of the coated sheet did not exceed 40% at wavelengths of 650 mu. FIG. 12 graphically illustrates the combined effect of an orange-red ink sprayed on a black substrate on a graph which correlates the spectral or reflective response of the eye and a typical copying process in percentages to light wavelengths measured in millimicrons under conditions of uniform illumination over the spectrum. Curve X identifies the response of the eye; curve Y the response of a typical copying system; and curve Z represents the combined reflectance of a coating of orange-red pigment on a black surbstrate or background. The shaded area between curves Y and Z represent the reflected light which reaches the detector or sensitized region of the copying system. From an m spection of the scale of FIG. 12 it can be determined that the background curve Z has a spectral response of substantially 4% over the wavelength range of substan tially 325 to 525 millimicrons which increases from substantially 7% at substantially 550 millimicrons to substantially 13% at the point where curves Y and Z intersect corresponding to about 575 millimicrons. When comparing the eye response curve X, which typically extends from about 425 to about 675 millimicrons, and the copying process curve Y, which typically extends from about 350 to 600 millimicrons, it becomes apparent that much more energy is available to fall upon the retina of the eye (since the intersection point is in the high response region of the eye response curve X) then is available for the detector of the typical copying machine (since the intersection point is at the low response portion of copying process curve Y Additionally, at wavelengths where the response of the copying machine system is greatest the response of the back ground is very small (substantially 4% at wavelengths lower than 525 millimicrons]. Thus with the particular background indicated in FIG. 12 and others similar thereto much more energy is available for detection by the eye than is available for detection by the copying machine. Since conventional inks normally used for ap plying graphical information to the background material have a substantially constant spectral response of about 5% which is similar to the response of the background in the portion of the spectrum where the copying process is most responsive there will be little or no net energy difference between the background and the graphical information for the copying process to be responsive to. However in the region of the spectrum where the eye is most responsive beyond the above referred to intersection point there is a sufficient difference in energy between the grapical information and background to be easily detected by the eye.
The orange-red ink was sprayed in such a manner as to form minute globules on the basic black background whereby the sheet appeared more orange when viewed at an angle slightly less than to the plane of the sheet than when viewed normal to the surface of the sheet. This coated sheet was then oversprayed with a thin film of varnish or lacquer to preclude the black graphical information. subsequently applied to such sheet, from diffusing into the orange/red background and to minimize the surface scattering, particularly in the spectral region of low reflectivity. This composite sheet can be used as an original in conventional typewriters or in any printing process using conventional black ink, or as feed stock to a copying machine to produce non-reproducible copies from the copyable original. In any event, the black graphical information imprinted on the composite orange/red background offered sufficient contrast to render the document easily readable by the human eye at typical viewing angles but of insufficient contrast to produce a useful image in a copying machine whereby a copy produced by the lat ter was unintelligible.
It should be appreciated that in most applications it is necessary to treat and render only selective portions of a document copy resistant in order to produce worthless copies by known copying processes. and the concept is applicable to all the forms of the invention hereinbefore described and those forms that will hereinafter be described. The portions or areas selected to be copy resistant or non reproducable by conventional copying machines can be artistically treated so as to form an aesthetic or pleasing background for the graphical information imprinted thereon. For example, a corporate insignia, a trademark, or other identifying symbols can be employed as the background pattern in these selected portions.
While numerous examples can be cited to illustrate the above concept, the following is one illustrative example of preparing a non-uniform background to obtain a desired loss of intelligibility in the copy in accordance with the last mentioned copy resistance tech nique described.
EXAMPLE A dense, gray-black ink was spray coated along the opposite sides and bottom marginal edges of a sheet of white paper to form a relatively dark border therealong about l.5 inches wide. The ink was sprayed inwardly of this border at progressively lighter shades to form a ta' pering ligher background inwardly of the border and terminating in a white background centrally of the document. This sheet was oversprayed with an orange/red ink to form minute globules thereon similarly to that disclosed in the first Example, except that the reflectance at the center of the sheet was maintained as large as desired while the reflectance along the black border was maintained below 30%. A suitable lacquer or var nish may be sprayed over the multicolored original, as desired. Black graphical information was imprinted on the multi-colored sheet to form a document which was processed through a conventional copying machine. While readability of the original was satisfactory, the intelligibility of the copy produced by the copying machine was low because the graphical information along the darkened border was unreadable. The copy produced depicted a clear intelligible central portion but an obliterated marginal edge portion. As previously mentioned, it was only necessary to obliterate portions of the graphical information of the copy to render it worthless. The obliteration of certain Words, sentences, or one marginal edge of the graphical information on the copy generally would defeat its utility. However, top security original documents and those of an extreme sensitive nature should be entirely treated to render them completely uncopyable to preclude any possibility of deciphering copies made therefrom.
Still another form of this invention for producing copy resistant documents in the utilization of photochromic, phototropic or photothermic materials, which change their optical properties such as color and/or op tical density when subjected to changes in light or heat, respectively. These materials can be used as dyes, pigments, inks, films or papers to modify the contrast between the background sheet and the graphical information imprinted thereon under changing conditions of light and heat. These materials may be used in an almost infinite variety of combinations to effect a change in either color or density contrast to impair the reproduction of an original document by various known copying machines. As a simple illustration of this method, a photochromic orange dye is employed as the background color upon which is imprinted black graphical information. This provides a good contrast for suitable readibility under normal illumination conditions but when exposed to the high intensity illumination incorporated in many copying machines, the orange background darkens to substantially reduce the contrast between the background and the graphical information observed by the copying machine optics, to impair the reproductability of the original.
It should be understood that photochromic, phototropic or photothermic materials, hereinafter referred to only as photochromic materials, can be in the form of a dye added to the base stock paper material to form the background thereof, as a coating on the paper stock, as a printing ink, or as a film to be applied to the paper stock after the graphical information has been imprinted thereon. The term photochromic as used herein is intended to include any and all materials which undergo a change in their optical properties, such as color and/or optical density when subjected to changes in light intensity and embraces materials which undergo a permanent change of color, those that revert back to their original color, or those that may require a different stimulus in order to revert back to their normal or inactivated state.
A photochromic material for this application should respond to. or be activated by, the radiation present in the illumination source of the copying machine and should not be activated by those elements of the radiation spectrum of the sun and artificial illumination not present in the copy machine so as to prevent or minimize the change of the contrast of the document under normal viewing conditions. As a generalization, the illumination sources in copy machines have a very low percentage of their radiation in the ultraviolet portion of the spectrum, whereas sunlight is strong in ultraviolet and the predominance of photochromic materials studied to date are activated in the ultraviolet region and show a color or density change in the visible portion of the spectrum. Also, most photochromic materials, by design, do not change their absorption or reflection properties at their excitation wavelengths; hence, the longer they are exposed, the greater the color Change to be expected. In order words, the spectral change is the product of the intensity of the illumination at the excitataion wavelength and time, or until the entire photochromic materials has converted, as the limit.
In accordance with this form of the invention, the photochromic material should be excited in the visible or infra red portion of the spectrum and should darken" or react at the excitation wavelength as well as elsewhere in the spectrum, such that the material arrives at a photo-stable condition as a function of the light intensity and will not go to total conversion with long time exposure at low levels of illumination. The dithizonates and the heavy metal complexes of dithizone are excellent examples of a class of suitable photochromic materials.
As an illustration, a solution of mercury bisdithizonate, which is orange in its unexcited state and shifts to blue upon excitation by radiation which includes blue, can be applied as a thin, transparent coating on orange paper. Under normal illumination, the film remains orange with a slight shift to the yellow and readibility is not impaired. With increasing illumina tion, as in a copy machine, the film shifts to the blue. This blue filter in combination with the orange background appears almost black, thus reducing the contrast between the background and the graphical information printed thereon to a very low level. It may be desirable to employ an ultra violet absorber in conjunction with the dithizonate to protect the dithizonate from the ultra violet radiation, such as occurs in normal sunlight and which may have a harmful effect on the dithizonate.
In lieu of a photochromic film, the graphical information can be printed with an opaque orange photochromic ink, produced for example, from a dithizonate and which darkens to a gray-brown upon high intensity irradiation in the visible portion of the spectrum to degrade the copy produced by a light activated copying machine. While dithizonates and heavy metal complexes of dithizone are preferably used as the photochromic materials in the above examples because of their sensitivity in the visible portion of the spectrum and their rapid responses to varying illumination, it should be understood that this invention is in no manner limited to the use of such dithizonates but can employ any suitable photochromic materials within the purview of this invention.
A still further form of this invention utilizes ultra violet and infra red absorbing materials, such as those offered by the American Cyanamil Corp. of Boundbrook, N.J., which are transparent in the visible spectrum and which can be added to the background materials, the film or the inks The inclusion of these materials in the document to be protected serves to limit the spectral band width of the light relfected from the document to the band width of the eye. Accordingly, the readability of the document will not be affected but any copying process which is sensitive in the ultra violet or the infra red regions of the spectrum will be degraded. For example such ultra violet and infra red absorbing materi als may be included in the photochromic orange pigment applied to the substrate in the example previously described Indeed. all of the copy resistant documents hereinbefore described can be treated with either an infra red or ultra violet absorbing material or a combination of both to attenuate the reflected infra red and- /or ultra violet energy so as not to affect contrast for human eye readability but to materially affect or reduce contrast for creating a poor image for reproduction by a copying machine.
From the foregoing, it is apparent that the present in vention fully accomplishes its intended objects and provides methods for treating or producing original docu ments in such a manner as to at least inhibit the production of intelligible copies therefrom by conventional copying machines.
Preferred forms of this invention having been dis closed in detail, it is to be understood that modifications thereof can be made without departing from the broad spirit and scope of this invention 1 claim:
1. A sheet of material adapted to have graphical information applied thereto which can be detected by the retinas of human eyes having typical spectral responses 7 in the range of substantially 425 to 675 millimicrons, but which cannot be detected by the detectors of copying machines having spectral responses typically in the range of substantially 350 to 600 millimicrons, comprising; a sheet of material at least a portion of which have a reflectance of substantially 4% over the wavelength of substantially 325 millimicrons to substantially S25 millimicrons, and a reflectance which increases from substantially 4% at substantially S25 millimicrons to substantially 7% at 550 and which then increases to substantially 13% at substantially 575 millimicrons, whereby insufficient reflected energy is available from said sheet of material and graphical information thereon to be distinguished by the detectors of typical copying machines at wavelengths to which they are most sensitive whereas sufficient reflected energy is available from said sheet of material and graphical information thereon to be distinguished by the retinas of human eyes at wavelengths to which they are most sensitive.
2. The sheet of material according to claim 1, wherein said portion is a dark orange 3. The sheet of material according to claim 2, further comprising graphical information on said sheet of ma terial having an average reflectance closer in value to 7% than 13% at all wavelengths 4. The sheet of material according to claim 3 wherein the reflectance of said graphical information is substantially 5% S. The sheet of material according to claim 1 further comprising graphical information on said sheet of material having an average reflectance closer in value to 7% than 13% at all wavelengths.
6. The sheet of material according to claim 5 wherein the reflectance of said graphical information is substantially 5%,

Claims (6)

1. A Sheet of material adapted to have graphical information applied thereto which can be detected by the retinas of human eyes having typical spectral responses in the range of substantially 425 to 675 millimicrons, but which cannot be detected by the detectors of copying machines having spectral responses typically in the range of substantially 350 to 600 millimicrons, comprising; a sheet of material at least a portion of which have a reflectance of substantially 4% over the wavelength of substantially 325 millimicrons to substantially 525 millimicrons, and a reflectance which increases from substantially 4% at substantially 525 millimicrons to substantially 7% at 550 and which then increases to substantially 13% at substantially 575 millimicrons, whereby insufficient reflected energy is available from said sheet of material and graphical information thereon to be distinguished by the detectors of typical copying machines at wavelengths to which they are most sensitive whereas sufficient reflected energy is available from said sheet of material and graphical information thereon to be distinguished by the retinas of human eyes at wavelengths to which they are most sensitive.
1. A Sheet of material adapted to have graphical information applied thereto which can be detected by the retinas of human eyes having typical spectral responses in the range of substantially 425 to 675 millimicrons, but which cannot be detected by the detectors of copying machines having spectral responses typically in the range of substantially 350 to 600 millimicrons, comprising; a sheet of material at least a portion of which have a reflectance of substantially 4% over the wavelength of substantially 325 millimicrons to substantially 525 millimicrons, and a reflectance which increases from substantially 4% at substantially 525 millimicrons to substantially 7% at 550 and which then increases to substantially 13% at substantially 575 millimicrons, whereby insufficient reflected energy is available from said sheet of material and graphical information thereon to be distinguished by the detectors of typical copying machines at wavelengths to which they are most sensitive whereas sufficient reflected energy is available from said sheet of material and graphical information thereon to be distinguished by the retinas of human eyes at wavelengths to which they are most sensitive.
2. The sheet of material according to claim 1, wherein said portion is a dark orange.
3. The sheet of material according to claim 2, further comprising graphical information on said sheet of material having an average reflectance closer in value to 7% than 13% at all wavelengths.
4. The sheet of material according to claim 3 wherein the reflectance of said graphical information is substantially 5%.
5. The sheet of material according to claim 1 further comprising graphical information on said sheet of material having an average reflectance closer in value to 7% than 13% at all wavelengths.
US243743A 1972-04-13 1972-04-13 Copy resistant documents Expired - Lifetime US3887742A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US243743A US3887742A (en) 1972-04-13 1972-04-13 Copy resistant documents
US05/562,512 US4025673A (en) 1972-04-13 1975-03-27 Method of forming copy resistant documents by forming an orderly array of fibers extending upward from a surface, coating the fibers and printing the coated fibers and the copy resistant document resulting from said method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US243743A US3887742A (en) 1972-04-13 1972-04-13 Copy resistant documents

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US05/562,512 Division US4025673A (en) 1972-04-13 1975-03-27 Method of forming copy resistant documents by forming an orderly array of fibers extending upward from a surface, coating the fibers and printing the coated fibers and the copy resistant document resulting from said method

Publications (1)

Publication Number Publication Date
US3887742A true US3887742A (en) 1975-06-03

Family

ID=22919943

Family Applications (1)

Application Number Title Priority Date Filing Date
US243743A Expired - Lifetime US3887742A (en) 1972-04-13 1972-04-13 Copy resistant documents

Country Status (1)

Country Link
US (1) US3887742A (en)

Cited By (70)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4025673A (en) * 1972-04-13 1977-05-24 Reinnagel Richard E Method of forming copy resistant documents by forming an orderly array of fibers extending upward from a surface, coating the fibers and printing the coated fibers and the copy resistant document resulting from said method
FR2331451A1 (en) * 1975-11-14 1977-06-10 Orell Fuessli Graph Betr Ag GRAPHIC DEVICE
US4118122A (en) * 1977-02-07 1978-10-03 Xerox Corporation Method of rendering objects uncopyable by photocopy processes
FR2402907A1 (en) * 1977-09-07 1979-04-06 Opax Lotteries Internal Nv Card for use in competitions - has opaque layer over intermediate masking layer with both removed to reveal data on card
US4175776A (en) * 1978-01-05 1979-11-27 New England Mutual Life Insurance Company Counterfeit resistant document
US4184700A (en) * 1975-11-17 1980-01-22 Lgz Landis & Gyr Zug Ag Documents embossed with optical markings representing genuineness information
US4227720A (en) * 1978-11-08 1980-10-14 Burroughs Corporation Protected document
US4265469A (en) * 1977-05-18 1981-05-05 Burroughs Corporation Protected document and method of making same
US4281921A (en) * 1979-09-17 1981-08-04 Auken John A Van Plural color anti-copying systems for xerographic and electrostatic copying machines
US4303307A (en) * 1977-10-27 1981-12-01 Al Tureck Copy security system
US4310180A (en) * 1977-05-18 1982-01-12 Burroughs Corporation Protected document and method of making same
FR2503890A1 (en) * 1979-09-17 1982-10-15 Auken John Van Multi-colour anti-copying system for e.g. xerographic copier - uses pre-selected background and image colours for colouring original document to prevent copying
EP0111597A1 (en) * 1981-05-25 1984-06-27 Nocopi International Inc. Method of rendering documents resistant to photocopying, and anti-copying paper
EP0119344A1 (en) * 1983-03-16 1984-09-26 Norman A. Gardner Method of rendering documents resistant to photocopying and anticopying paper therefor
US4586811A (en) * 1982-04-23 1986-05-06 Ricoh Company, Ltd. Confidential document reproduction prevention method
EP0180396A2 (en) * 1984-10-23 1986-05-07 Canon Kabushiki Kaisha Recording medium and recording method utilizing the same
US4705300A (en) * 1984-07-13 1987-11-10 Optical Coating Laboratory, Inc. Thin film optically variable article and method having gold to green color shift for currency authentication
US4779898A (en) * 1986-11-21 1988-10-25 Optical Coating Laboratory, Inc. Thin film optically variable article and method having gold to green color shift for currency authentication
US4786084A (en) * 1985-11-18 1988-11-22 Copyguard, Inc. Volumetric holographic photocopy prevention film
GB2212445A (en) * 1987-11-17 1989-07-26 Chubb Electronics Ltd Data carriers
US4856857A (en) * 1985-05-07 1989-08-15 Dai Nippon Insatsu Kabushiki Kaisha Transparent reflection-type
DE3843076A1 (en) * 1988-12-21 1990-07-05 Gao Ges Automation Org SECURITY ELEMENT TO PROTECT DOCUMENTS AGAINST UNAUTHORIZED REPRODUCTION
GB2238755A (en) * 1989-11-09 1991-06-12 Kiso Kasei Sangyo Co Ltd Security paper
US5149578A (en) * 1989-12-26 1992-09-22 The Dow Chemical Company Multilayer film for tamper indication by use of optical interference reflection
WO1994004366A1 (en) * 1992-08-14 1994-03-03 Basf Magnetics Gmbh Film or layer of transparent material, in particular plastic material
WO1994009990A1 (en) * 1992-10-29 1994-05-11 Basf Magnetics Gmbh Anti-copying film or layer
US5351142A (en) * 1993-04-16 1994-09-27 Crown Roll Leaf, Inc. Semi-transparent reflective layer for a phase hologram
DE4320219A1 (en) * 1993-06-18 1994-12-22 Basf Magnetics Gmbh Anticopy film
EP0640493A2 (en) * 1993-08-24 1995-03-01 BASF Magnetics GmbH Anti-copy film
DE4321685A1 (en) * 1993-06-30 1995-03-23 Basf Magnetics Gmbh Anticopy film
WO1995023710A1 (en) * 1994-03-02 1995-09-08 Applied Physics Research, L.P. Light control material and method for making same
US5475533A (en) * 1993-08-02 1995-12-12 Applied Physics Research, L.P. Apparatus for enhancing the brightness of an image and method of making the same
US5487567A (en) * 1992-04-24 1996-01-30 Francois-Charles Oberthur Group Printing method and copy-evident secure document
US5513019A (en) * 1993-04-16 1996-04-30 Crown Roll Leaf, Inc. Semi-transparent reflective layer for a phase hologram
US5683805A (en) * 1995-10-27 1997-11-04 Lintec Corporation Colored film
US5695808A (en) * 1993-04-16 1997-12-09 Crown Roll Leaf Inc. Method for making transparent reflective films
US5728449A (en) * 1992-08-14 1998-03-17 Emtec Magnetics Gmbh Anti-copy film layer for documents
US5823576A (en) * 1994-05-06 1998-10-20 Lew Lambert Copy-resistant document
DE19749789A1 (en) * 1997-11-11 1999-05-12 Bundesdruckerei Gmbh Security feature for a value or security document with a fractal lamella system
US5948199A (en) * 1983-06-20 1999-09-07 Mcgrew; Stephen Paul Surface relief holograms and holographic hot-stamping foils, and method of fabricating same
US5951769A (en) * 1997-06-04 1999-09-14 Crown Roll Leaf, Inc. Method and apparatus for making high refractive index (HRI) film
US6107244A (en) * 1997-10-15 2000-08-22 Nashua Corporation Verification methods employing thermally--imageable substrates
US6294251B1 (en) 1998-01-13 2001-09-25 Lintec Corporation Colored film
US6396927B1 (en) * 1995-05-25 2002-05-28 Verify First Technologies, Inc. Variable density verification
US20020143671A1 (en) * 1998-10-29 2002-10-03 International Business Machines Corporation Method and system for preventing parallel marketing of wholesale and retail items
US6631987B2 (en) * 2001-01-23 2003-10-14 Nike, Inc. Activity-specific optical filters and eyewear using such filters
US20050134924A1 (en) * 2003-12-23 2005-06-23 Jacob Steve A. Image adjustment
EP1580020A1 (en) * 2004-03-24 2005-09-28 Kba-Giori S.A. Intaglio printing plate
US20060000011A1 (en) * 2004-06-30 2006-01-05 Nike, Inc. Optically decentered face shield
EP1680285A2 (en) * 2003-11-04 2006-07-19 De La Rue International Limited Security device
US20070262154A1 (en) * 2006-05-15 2007-11-15 Victor Zazzu Secure product authentication tags
WO2008049533A2 (en) 2006-10-24 2008-05-02 Giesecke & Devrient Gmbh See-through security element with microstructures
FR2942811A1 (en) * 2009-03-04 2010-09-10 Oberthur Technologies SECURITY ELEMENT FOR DOCUMENT-VALUE.
US20100308571A1 (en) * 2003-11-21 2010-12-09 Visual Physics, Llc Optical system demonstrating improved resistance to optically degrading external effects
US20110019283A1 (en) * 2003-11-21 2011-01-27 Visual Physics, Llc Tamper indicating optical security device
WO2011060910A1 (en) * 2009-11-19 2011-05-26 Giesecke & Devrient Gmbh Security element having a microstructure
US8755121B2 (en) 2011-01-28 2014-06-17 Crane & Co., Inc. Laser marked device
CN104335097A (en) * 2012-06-01 2015-02-04 凸版印刷株式会社 Anisotropic reflection display unit, and information storage unit using anisotropic reflection display unit
US9873281B2 (en) 2013-06-13 2018-01-23 Visual Physics, Llc Single layer image projection film
US10173405B2 (en) 2012-08-17 2019-01-08 Visual Physics, Llc Process for transferring microstructures to a final substrate
US10173453B2 (en) 2013-03-15 2019-01-08 Visual Physics, Llc Optical security device
US10189292B2 (en) 2015-02-11 2019-01-29 Crane & Co., Inc. Method for the surface application of a security device to a substrate
US10195890B2 (en) 2014-09-16 2019-02-05 Crane Security Technologies, Inc. Secure lens layer
EP3330949A4 (en) * 2015-07-27 2019-04-24 Yu, Chi Anti-counterfeit label and manufacturing method therefor
US10434812B2 (en) 2014-03-27 2019-10-08 Visual Physics, Llc Optical device that produces flicker-like optical effects
EP3166798B1 (en) 2014-07-07 2020-08-19 Security Fibres UK Limited Improvements in and relating to security documents
US10766292B2 (en) 2014-03-27 2020-09-08 Crane & Co., Inc. Optical device that provides flicker-like optical effects
US10800203B2 (en) 2014-07-17 2020-10-13 Visual Physics, Llc Polymeric sheet material for use in making polymeric security documents such as banknotes
US10890692B2 (en) 2011-08-19 2021-01-12 Visual Physics, Llc Optionally transferable optical system with a reduced thickness
US11590791B2 (en) 2017-02-10 2023-02-28 Crane & Co., Inc. Machine-readable optical security device

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US690148A (en) * 1895-08-26 1901-12-31 Charles M Higgins Bank-check, &c., and writing fabric for same.
US2936247A (en) * 1957-06-19 1960-05-10 Caribonum Ltd Transfer sheets for forming thermosensitive copies
US2952080A (en) * 1957-09-12 1960-09-13 Teleregister Corp Cryptic grid scrambling and unscrambling method and apparatus
US2992121A (en) * 1957-05-16 1961-07-11 Caribonum Ltd Thermosensitive colouring materials
US3001857A (en) * 1958-06-05 1961-09-26 Robert T Pollock Up-grading of diesel fuels
US3671451A (en) * 1968-03-27 1972-06-20 American Cyanamid Co Fluorescent compositions

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US690148A (en) * 1895-08-26 1901-12-31 Charles M Higgins Bank-check, &c., and writing fabric for same.
US2992121A (en) * 1957-05-16 1961-07-11 Caribonum Ltd Thermosensitive colouring materials
US2936247A (en) * 1957-06-19 1960-05-10 Caribonum Ltd Transfer sheets for forming thermosensitive copies
US2952080A (en) * 1957-09-12 1960-09-13 Teleregister Corp Cryptic grid scrambling and unscrambling method and apparatus
US3001857A (en) * 1958-06-05 1961-09-26 Robert T Pollock Up-grading of diesel fuels
US3671451A (en) * 1968-03-27 1972-06-20 American Cyanamid Co Fluorescent compositions

Cited By (117)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4025673A (en) * 1972-04-13 1977-05-24 Reinnagel Richard E Method of forming copy resistant documents by forming an orderly array of fibers extending upward from a surface, coating the fibers and printing the coated fibers and the copy resistant document resulting from said method
FR2331451A1 (en) * 1975-11-14 1977-06-10 Orell Fuessli Graph Betr Ag GRAPHIC DEVICE
US4124947A (en) * 1975-11-14 1978-11-14 Adolf Kuhl Graphic pattern or the like and method of producing the same
US4184700A (en) * 1975-11-17 1980-01-22 Lgz Landis & Gyr Zug Ag Documents embossed with optical markings representing genuineness information
US4118122A (en) * 1977-02-07 1978-10-03 Xerox Corporation Method of rendering objects uncopyable by photocopy processes
US4265469A (en) * 1977-05-18 1981-05-05 Burroughs Corporation Protected document and method of making same
US4310180A (en) * 1977-05-18 1982-01-12 Burroughs Corporation Protected document and method of making same
FR2402907A1 (en) * 1977-09-07 1979-04-06 Opax Lotteries Internal Nv Card for use in competitions - has opaque layer over intermediate masking layer with both removed to reveal data on card
US4303307A (en) * 1977-10-27 1981-12-01 Al Tureck Copy security system
US4175776A (en) * 1978-01-05 1979-11-27 New England Mutual Life Insurance Company Counterfeit resistant document
US4227720A (en) * 1978-11-08 1980-10-14 Burroughs Corporation Protected document
US4281921A (en) * 1979-09-17 1981-08-04 Auken John A Van Plural color anti-copying systems for xerographic and electrostatic copying machines
FR2503890A1 (en) * 1979-09-17 1982-10-15 Auken John Van Multi-colour anti-copying system for e.g. xerographic copier - uses pre-selected background and image colours for colouring original document to prevent copying
EP0111597A1 (en) * 1981-05-25 1984-06-27 Nocopi International Inc. Method of rendering documents resistant to photocopying, and anti-copying paper
US4632429A (en) * 1981-05-25 1986-12-30 Nocoi Inc. Method of rendering documents resistant to photocopying and anti-copying paper therefor
US4586811A (en) * 1982-04-23 1986-05-06 Ricoh Company, Ltd. Confidential document reproduction prevention method
EP0119344A1 (en) * 1983-03-16 1984-09-26 Norman A. Gardner Method of rendering documents resistant to photocopying and anticopying paper therefor
US5948199A (en) * 1983-06-20 1999-09-07 Mcgrew; Stephen Paul Surface relief holograms and holographic hot-stamping foils, and method of fabricating same
US4705300A (en) * 1984-07-13 1987-11-10 Optical Coating Laboratory, Inc. Thin film optically variable article and method having gold to green color shift for currency authentication
EP0180396A2 (en) * 1984-10-23 1986-05-07 Canon Kabushiki Kaisha Recording medium and recording method utilizing the same
EP0180396A3 (en) * 1984-10-23 1987-10-28 Canon Kabushiki Kaisha Recording medium and recording method utilizing the same
US4956223A (en) * 1984-10-23 1990-09-11 Canon Kabushiki Kaisha Recording medium and recording method utilizing the same
US4856857A (en) * 1985-05-07 1989-08-15 Dai Nippon Insatsu Kabushiki Kaisha Transparent reflection-type
US4786084A (en) * 1985-11-18 1988-11-22 Copyguard, Inc. Volumetric holographic photocopy prevention film
US4779898A (en) * 1986-11-21 1988-10-25 Optical Coating Laboratory, Inc. Thin film optically variable article and method having gold to green color shift for currency authentication
GB2212445A (en) * 1987-11-17 1989-07-26 Chubb Electronics Ltd Data carriers
GB2212445B (en) * 1987-11-17 1991-09-18 Chubb Electronics Ltd Data carriers
DE3843076A1 (en) * 1988-12-21 1990-07-05 Gao Ges Automation Org SECURITY ELEMENT TO PROTECT DOCUMENTS AGAINST UNAUTHORIZED REPRODUCTION
GB2238755B (en) * 1989-11-09 1993-04-28 Kiso Kasei Sangyo Co Ltd Paper for protecting against the reproduction of documents
GB2238755A (en) * 1989-11-09 1991-06-12 Kiso Kasei Sangyo Co Ltd Security paper
US5149578A (en) * 1989-12-26 1992-09-22 The Dow Chemical Company Multilayer film for tamper indication by use of optical interference reflection
US5487567A (en) * 1992-04-24 1996-01-30 Francois-Charles Oberthur Group Printing method and copy-evident secure document
WO1994004366A1 (en) * 1992-08-14 1994-03-03 Basf Magnetics Gmbh Film or layer of transparent material, in particular plastic material
US5728449A (en) * 1992-08-14 1998-03-17 Emtec Magnetics Gmbh Anti-copy film layer for documents
US5795643A (en) * 1992-10-29 1998-08-18 Basf Magnetics Gmbh Anticopying film
WO1994009990A1 (en) * 1992-10-29 1994-05-11 Basf Magnetics Gmbh Anti-copying film or layer
US5351142A (en) * 1993-04-16 1994-09-27 Crown Roll Leaf, Inc. Semi-transparent reflective layer for a phase hologram
US5695808A (en) * 1993-04-16 1997-12-09 Crown Roll Leaf Inc. Method for making transparent reflective films
US5513019A (en) * 1993-04-16 1996-04-30 Crown Roll Leaf, Inc. Semi-transparent reflective layer for a phase hologram
DE4320219A1 (en) * 1993-06-18 1994-12-22 Basf Magnetics Gmbh Anticopy film
GB2280639A (en) * 1993-06-18 1995-02-08 Basf Magnetics Gmbh An applied film to prevent copying of a document.
GB2280639B (en) * 1993-06-18 1996-12-18 Basf Magnetics Gmbh Anticopy film
GB2283701A (en) * 1993-06-30 1995-05-17 Basf Magnetics Gmbh An applied film to prevent copying of a document.
DE4321685A1 (en) * 1993-06-30 1995-03-23 Basf Magnetics Gmbh Anticopy film
GB2283701B (en) * 1993-06-30 1997-03-26 Basf Magnetics Gmbh Anticopying film
US5475533A (en) * 1993-08-02 1995-12-12 Applied Physics Research, L.P. Apparatus for enhancing the brightness of an image and method of making the same
US5569522A (en) * 1993-08-24 1996-10-29 Basf Magnetics Gmbh Anticopying film
EP0640493A3 (en) * 1993-08-24 1995-06-28 Basf Magnetics Gmbh Anti-copy film.
EP0640493A2 (en) * 1993-08-24 1995-03-01 BASF Magnetics GmbH Anti-copy film
WO1995023710A1 (en) * 1994-03-02 1995-09-08 Applied Physics Research, L.P. Light control material and method for making same
US5823576A (en) * 1994-05-06 1998-10-20 Lew Lambert Copy-resistant document
US6396927B1 (en) * 1995-05-25 2002-05-28 Verify First Technologies, Inc. Variable density verification
US6665406B1 (en) * 1995-05-25 2003-12-16 Verify First Technologies, Inc. Variable density verification
US5683805A (en) * 1995-10-27 1997-11-04 Lintec Corporation Colored film
US5951769A (en) * 1997-06-04 1999-09-14 Crown Roll Leaf, Inc. Method and apparatus for making high refractive index (HRI) film
US6194031B1 (en) 1997-06-04 2001-02-27 Crown Roll Leaf, Inc. Method for making high refractive index (HRI) film by adjusting the flow rate of a vaporized material
US6107244A (en) * 1997-10-15 2000-08-22 Nashua Corporation Verification methods employing thermally--imageable substrates
EP1030786B1 (en) * 1997-11-11 2002-06-05 BUNDESDRUCKEREI GmbH Security feature for a security document or document of value with a fractal laminate system
EP1030786A1 (en) * 1997-11-11 2000-08-30 BUNDESDRUCKEREI GmbH Security feature for a security document or document of value with a fractal laminate system
DE19749789A1 (en) * 1997-11-11 1999-05-12 Bundesdruckerei Gmbh Security feature for a value or security document with a fractal lamella system
US6294251B1 (en) 1998-01-13 2001-09-25 Lintec Corporation Colored film
US6817538B2 (en) 1998-10-29 2004-11-16 International Business Machines Corporation Method and system for preventing parallel marketing of wholesale and retail items
US20020143671A1 (en) * 1998-10-29 2002-10-03 International Business Machines Corporation Method and system for preventing parallel marketing of wholesale and retail items
US6746053B1 (en) * 1998-10-29 2004-06-08 International Business Machines Corporation Method and system for preventing parallel marketing of wholesale and retail items
US6631987B2 (en) * 2001-01-23 2003-10-14 Nike, Inc. Activity-specific optical filters and eyewear using such filters
EP1680285B1 (en) * 2003-11-04 2015-04-01 De La Rue International Limited Security device
US7997625B2 (en) 2003-11-04 2011-08-16 De La Ru International Limited Security device
EP1680285A2 (en) * 2003-11-04 2006-07-19 De La Rue International Limited Security device
US20070132227A1 (en) * 2003-11-04 2007-06-14 Dean Julia R Security device
US8773763B2 (en) 2003-11-21 2014-07-08 Visual Physics, Llc Tamper indicating optical security device
US20110019283A1 (en) * 2003-11-21 2011-01-27 Visual Physics, Llc Tamper indicating optical security device
US20100308571A1 (en) * 2003-11-21 2010-12-09 Visual Physics, Llc Optical system demonstrating improved resistance to optically degrading external effects
US8867134B2 (en) 2003-11-21 2014-10-21 Visual Physics, Llc Optical system demonstrating improved resistance to optically degrading external effects
US20050134924A1 (en) * 2003-12-23 2005-06-23 Jacob Steve A. Image adjustment
US7256913B2 (en) * 2003-12-23 2007-08-14 Hewlett-Packard Development Company, L.P. Image adjustment
WO2005090090A1 (en) * 2004-03-24 2005-09-29 Kba-Giori S.A. Intaglio printing plate
EP1580020A1 (en) * 2004-03-24 2005-09-28 Kba-Giori S.A. Intaglio printing plate
US7389543B2 (en) 2004-06-30 2008-06-24 Nike, Inc. Optically decentered face shield
US20060000011A1 (en) * 2004-06-30 2006-01-05 Nike, Inc. Optically decentered face shield
US7744130B2 (en) * 2006-05-15 2010-06-29 Victor Zazzu Secure product authentication tags
US20070262154A1 (en) * 2006-05-15 2007-11-15 Victor Zazzu Secure product authentication tags
WO2008049533A3 (en) * 2006-10-24 2009-01-15 Giesecke & Devrient Gmbh See-through security element with microstructures
US20100194091A1 (en) * 2006-10-24 2010-08-05 Giesecke & Devrient Gmbh See-through security element with microstructures
WO2008049533A2 (en) 2006-10-24 2008-05-02 Giesecke & Devrient Gmbh See-through security element with microstructures
CN101528474B (en) * 2006-10-24 2012-05-23 德国捷德有限公司 See-through security element with microstructures
US8534708B2 (en) 2006-10-24 2013-09-17 Giesecke & Devrient Gmbh See-through security element with microstructures
AU2010219575B2 (en) * 2009-03-04 2013-03-28 Oberthur Fiduciaire Sas Security element for a value document
WO2010100360A1 (en) * 2009-03-04 2010-09-10 Oberthur Technologies Security element for a value document
FR2942811A1 (en) * 2009-03-04 2010-09-10 Oberthur Technologies SECURITY ELEMENT FOR DOCUMENT-VALUE.
US9016726B2 (en) * 2009-11-19 2015-04-28 Giesecke & Devrient Gmbh Security element having a microstructure
WO2011060910A1 (en) * 2009-11-19 2011-05-26 Giesecke & Devrient Gmbh Security element having a microstructure
EP3075562A1 (en) * 2009-11-19 2016-10-05 Giesecke & Devrient GmbH Security element having a microstructure
US20120228860A1 (en) * 2009-11-19 2012-09-13 Giesecke & Devrient Gmbh Security element having a microstructure
US8755121B2 (en) 2011-01-28 2014-06-17 Crane & Co., Inc. Laser marked device
US9333787B2 (en) 2011-01-28 2016-05-10 Visual Physics, Llc Laser marked device
US10890692B2 (en) 2011-08-19 2021-01-12 Visual Physics, Llc Optionally transferable optical system with a reduced thickness
CN104335097A (en) * 2012-06-01 2015-02-04 凸版印刷株式会社 Anisotropic reflection display unit, and information storage unit using anisotropic reflection display unit
US10654308B2 (en) 2012-06-01 2020-05-19 Toppan Printing Co., Ltd. Unisometric reflection display, information holder using unisometric reflection display
EP2857872A4 (en) * 2012-06-01 2015-06-03 Toppan Printing Co Ltd Anisotropic reflection display unit, and information storage unit using anisotropic reflection display unit
JPWO2013180231A1 (en) * 2012-06-01 2016-01-21 凸版印刷株式会社 Anisotropic reflective display and information recording body using anisotropic reflective display
US9889699B2 (en) 2012-06-01 2018-02-13 Toppan Printing Co., Ltd. Unisometric reflection display, information holder using unisometric reflection display
CN104335097B (en) * 2012-06-01 2018-03-02 凸版印刷株式会社 Anisotropic emission display body and the authenticable information recording for having used anisotropic emission display body
US10173405B2 (en) 2012-08-17 2019-01-08 Visual Physics, Llc Process for transferring microstructures to a final substrate
US10899120B2 (en) 2012-08-17 2021-01-26 Visual Physics, Llc Process for transferring microstructures to a final substrate
US10173453B2 (en) 2013-03-15 2019-01-08 Visual Physics, Llc Optical security device
US10787018B2 (en) 2013-03-15 2020-09-29 Visual Physics, Llc Optical security device
US9873281B2 (en) 2013-06-13 2018-01-23 Visual Physics, Llc Single layer image projection film
US10434812B2 (en) 2014-03-27 2019-10-08 Visual Physics, Llc Optical device that produces flicker-like optical effects
US10766292B2 (en) 2014-03-27 2020-09-08 Crane & Co., Inc. Optical device that provides flicker-like optical effects
US11446950B2 (en) 2014-03-27 2022-09-20 Visual Physics, Llc Optical device that produces flicker-like optical effects
EP3166798B1 (en) 2014-07-07 2020-08-19 Security Fibres UK Limited Improvements in and relating to security documents
US10800203B2 (en) 2014-07-17 2020-10-13 Visual Physics, Llc Polymeric sheet material for use in making polymeric security documents such as banknotes
US10195890B2 (en) 2014-09-16 2019-02-05 Crane Security Technologies, Inc. Secure lens layer
US10189292B2 (en) 2015-02-11 2019-01-29 Crane & Co., Inc. Method for the surface application of a security device to a substrate
EP3330949A4 (en) * 2015-07-27 2019-04-24 Yu, Chi Anti-counterfeit label and manufacturing method therefor
US11308825B2 (en) 2015-07-27 2022-04-19 Chi Yu Anti-counterfeit label and manufacturing method therefor
US11590791B2 (en) 2017-02-10 2023-02-28 Crane & Co., Inc. Machine-readable optical security device

Similar Documents

Publication Publication Date Title
US3887742A (en) Copy resistant documents
US4025673A (en) Method of forming copy resistant documents by forming an orderly array of fibers extending upward from a surface, coating the fibers and printing the coated fibers and the copy resistant document resulting from said method
US5772248A (en) Document with tamper and counterfeit resistant relief markings
US7145723B2 (en) Security element
US5873604A (en) Document security system having thermo-activated pantograph and validation mark
CA2222177C (en) Counterfeit resistant documents and methods
US5350198A (en) Recording medium with colored picture information, in particular a check card or identity card
US4579754A (en) Identification card having laser inscribed indicia and a method of producing it
US4766026A (en) Identification card with a visible authenticity feature and a method of manufacturing said card
JP3938951B2 (en) Optically variable member and data carrier comprising the optically variable member
EP1973748B1 (en) Bragg diffracting security markers
AU600922B2 (en) Card data carrier and method of producing it
RU2339524C2 (en) Printing film for production of tamper-proof number plates and tamper-proof number plate containing printing film
US6665406B1 (en) Variable density verification
EP1983473B1 (en) Data carrier with codes
JPH05212993A (en) Method for producing certification card
US20070085337A1 (en) Data carrier and method for manufacturing the same
US5762378A (en) Tamper resistant validation marks
JPH0664206B2 (en) Directional imaged sheet
HU222697B1 (en) Data carrier, method for producing the data carrier as well as antifalsification paper
EP1492677A2 (en) Security element for use as photocopy protection
AU604671B2 (en) Data-carrier in card form and method of producing it
JPH1081060A (en) Duplication preventing medium and manufacture thereof
KR20070016132A (en) Embossed film for producing tamper-proof car license plates and tamper-proof car license plate comprising such an embossed film
WO1993008513A1 (en) Method of producing anti-reproduction coatings for documents