Fraud Or Tamper Detecting Patents (Class 428/915)
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Patent number: 5053260Abstract: An embossing foil such as a hot embossing foil is of a laminate structure comprising in succession a backing foil, a separating layer, a transparent cover lacquer, a decorative layer means and a foundation layer of an at least translucent material. The decorative layer means successively comprises a first decorative layer adjacent to the cover lacquer layer, an opaque intermediate layer and a second decorative layer adjacent to the foundation layer. The opaque intermediate layer can be covered at least on one side with a single-colored layer over a large area thereof.Type: GrantFiled: May 23, 1990Date of Patent: October 1, 1991Assignee: Leonhard Kurz GmbH & Co.Inventor: Ludwig Brehm
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Patent number: 5015318Abstract: The method involves forming a laminate capable of generating a substantially non-dichroic color by a light interference and absorption phenomenon by depositing a layer of a metal of medium light reflectivity by a vapor deposition technique on a suitable substrate, anodizing a surface of the metal in the presence of fluorine ions to form a detachable film of an oxide of the metal on the surface having a thickness suitable for color generation, and adhering a flexible strip of transparent or translucent material over the oxide film in such a manner that the strength of attachment of the flexible strip to the oxide film exceeds the adhesive strength between the oxide film and said surface of said metal.Type: GrantFiled: January 11, 1989Date of Patent: May 14, 1991Assignee: Alcan International LimitedInventors: Paul Smits, Aron M. Rosenfeld, Howard F. DeFerrari
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Patent number: 4994314Abstract: A laminated color change device which exhibits an irreversible color change upon delamination. The device comprises two layers capable of generating a color by a light interference and absorption phenomenon that requires direct and intimate contact between the two layers. One of the layers is a color-generating metal, such as a valve metal (e.g. tantalum), and the other is an overlying light-transmitting film thin enough to cause light interference effects. The film is produced by coating the color generating metal with aluminum or an aluminum alloy and then anodizing (preferably porous anodizing) the aluminum to consumption in the presence of an adhesion-reducing agent, e.g. fluoride, that reduces the strength of attachment between the layers so that the laminate can be uniformly and reliably separated at the interface between the adjacent two layers. An overlying layer of transparent or translucent material is normally adhered to the laminate to facilitate the separation of the layers.Type: GrantFiled: February 3, 1989Date of Patent: February 19, 1991Assignee: Alcan International LimitedInventors: Aron M. Rosenfeld, Paul Smits
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Patent number: 4980222Abstract: A tamper indicating tape for use with a closure or container. The tape comprises a film including phase separated polymers. Colored indicia are applied to opposing major surfaces of the film indicative of a condition that someone has tampered with the tape, e.g., tape removal and reattachment, or abrading. The film further bears a layer of adhesive thereon as a means for adhering the tape to a portion of a container or to a closure tape on a can lid. When the film of the tamper indicating tape is sufficiently split, one set of colored indicia is obscured and the other set of colored indicia is rendered perceptible. When the film is abraded to remove the perceptible set of colored indicia, the aforementioned obscured set of colored indicia is rendered perceptible.Type: GrantFiled: June 21, 1989Date of Patent: December 25, 1990Assignee: Minnesota Mining and Manufacturing CompanyInventors: Raymond R. Rivera, Shari J. Wilson, Stephen B. Vanvleet
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Patent number: 4940690Abstract: The present invention provides a laminate construction including a backing sheet, which may be in the form of a continuous web, and a face sheet covering at least a portion of the backing sheet. A releasable adhesive secures a first or lower surface of the face sheet to a first or upper surface of the backing sheet such that the face sheet and backing sheet are readily separable. The releasable adhesive contains therein a first composition which, when subjected to an imaging force, forms a latent image on both of the first surfaces of the face and backing sheets. This latent image may be developed at a later time by contacting the image with a second composition which, when exposed to the first composition, forms a visible image. In the laminate, the face sheet may be imprinted with legible and/or covert information. The covert information may be duplicated on the underside of the face sheet or on one or more intermediate sheets as well as a backing sheet.Type: GrantFiled: July 27, 1988Date of Patent: July 10, 1990Assignee: The Standard Register CompanyInventor: Hugh B. Skees
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Patent number: 4897300Abstract: The invention relates to a security paper having a security thread embedded therein, running from edge to edge, that is printed with luminescent colors in such a way that they are invisible in normal lighting. The luminescent colors are provided along the security thread in successive overlapping portions which, when the colors are excited, have a length recognizable to the naked eye and show characteristic mixed fluorescences in the overlapping areas.Type: GrantFiled: August 4, 1988Date of Patent: January 30, 1990Assignee: GAO Gesellschaft fuer Automation und Organisation mbHInventor: Michael Boehm
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Patent number: 4889749Abstract: An identification card comprises a center core layer, a photograph embedded in the core layer, a first assembly of multiple layers laminated on the upper surface of the core layer and the photograph, and a second assembly of multiple layers laminated on the back surface of the core layer and the photograph. The layers of the first and second assemblies have substantially similar thermal expansion properties. Accordingly, the thickness of the identification card is uniform since the thickness of the core layer is substantially the same as the thickness of the photograph. High reliability can be obtained without any accompanying warp as a result of the substantially symmetrical arrangement of the first and second assemblies with respect to the core layer and the embedded photograph.Type: GrantFiled: November 24, 1987Date of Patent: December 26, 1989Assignees: Ryoden Kasei Co., Ltd., Mitsubishi Denki Kabushiki KaishaInventors: Masato Ohashi, Shiyoojiro Kodai
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Patent number: 4869946Abstract: There is disclosed a unique tamperproof security card comprised of a transparent upper layer having narrow parallel lenses on the outer surface, and an image containing substrate, said two layers forming a lenticular system by which images on the substrate are selectively visible depending upon the angle from which the card is viewed. By incorporating into a selectively visible image the information necessary to verify the identify of the cardholder, e.g. the cardholder's photograph or signature, the card may be rendered substantially tamperproof.Type: GrantFiled: December 29, 1987Date of Patent: September 26, 1989Assignee: Nimslo CorporationInventor: Stanton T. Clay
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Patent number: 4841652Abstract: An adhesive sheet which comprises a support sheet and an adhesive layer containing a migratory substance, disposed on one side of the support sheet. This adhesive sheet may be applied to many types of articles and will leave behind a dye mark on the article indicating that it has been applied and subsequently removed.Type: GrantFiled: February 25, 1987Date of Patent: June 27, 1989Assignee: Efuesukei Kabushiki KaishaInventors: Hitoshi Sakashita, Yoshihisa Mineura, Toshihiko Sato
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Patent number: 4837061Abstract: The invention relates to a laminated tamper-evident structure which exhibits an irreversible color change upon delamination. The structure includes a laminate of at least two layers capable of generating a color by a light interference and absorption phenomenon that requires direct and intimate contact between an adjacent two of the layers. The strength of attachment among the layers of the laminate is such that the laminate can be uniformly and reliably peeled apart at the interface between the adjacent two layers. An overlying flexible strip of transparent or translucent material is adhered to the laminate to facilitate the peeling operation. Upon peeling apart the laminate, the generated color is irreversibly lost, thus providing evidence that the structure has been tampered with. The structure can be incorporated into a variety of closable articles or products to provide evidence of opening or tampering.Type: GrantFiled: August 10, 1987Date of Patent: June 6, 1989Assignee: Alcan International LimitedInventors: Paul Smits, Aron M. Rosenfeld, Howard F. DeFerrari
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Patent number: 4835028Abstract: A paper product includes both means for preventing images from being copied from the paper product by use of a xerographic photocopier; and means for enabling detection of the paper product when the paper product is transported through an interrogation zone of an article surveillance system.Type: GrantFiled: May 29, 1987Date of Patent: May 30, 1989Assignee: Security Tag Systems, Inc.Inventors: Subrata Dey, William R. Menyhert
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Patent number: 4788102Abstract: Data-carrying card comprising multiple layers which have been connected to each other with use of an adhesive and excluding the application of heat and pressure. In particular the invention relates to a card as described which incorporates an integrated electronic circuit. The invention also relates to a method for producing a card as described and to a device for carrying out said method.Type: GrantFiled: May 21, 1987Date of Patent: November 29, 1988Assignee: Papier-Plastic-Coating Groningen B.V.Inventors: Anthony A. Koning, Wim Dijkhuizen
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Patent number: 4756557Abstract: In order to increase the protection of security documents such as ban notes, etc., against forgery, security threads are embedded in the document which have at least two areas extending in the longitudinal direction of the thread and differing in their physical properties. The thread is preferably a coextruded multicomponent synthetic thread whose individual components contain additives such as dyes or fluorescent substances and/or particles having electrical or magnetic properties. The testing of the authenticity of the security thread is directed toward the presence of these additives and their mutual geometrical distribution in certain areas of the security thread.Type: GrantFiled: December 23, 1985Date of Patent: July 12, 1988Assignee: G.A.O. Gesellschaft fuer Automation und Organisation mbHInventors: Wittich Kaule, Gerhard Stenzel, Jurgen Moll, Gerhard Schwenk
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Patent number: 4738949Abstract: A dye-receiving element and process for producing a high-security, monolithic identification card, the element comprising a support having thereon a dye image-receiving layer adapted to receive a thermally-transferred dye image, the dye image-receiving layer containing indicia printed thereon approximately 40-120 .mu.m in width.Type: GrantFiled: December 29, 1986Date of Patent: April 19, 1988Assignee: Eastman Kodak CompanyInventors: Gurdip S. Sethi, Stephen D. Marshall, David E. Wenschhof
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Patent number: 4725497Abstract: This invention relates to an unfalsifiable safety paper comprising on its surface and/or in its mass, at least one compound responding to formula: ##STR1## in which: R corresponds to hydrogen, to an alkyl group of C.sub.1 to C.sub.8, substituted or not, to a non-substituted, N-substituted or N,N-substituted amine group, to NO.sub.2, to a halogen;n is equal to 0 or 1.The invention is applicable to handwritten pieces for payment.Type: GrantFiled: January 17, 1986Date of Patent: February 16, 1988Assignee: Societe Anonyme: Aussedat-ReyInventors: Andre Honnorat, Claude Riou, Louis Raux
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Patent number: 4662653Abstract: A security element for authenticating bank notes, credit cards, security passes and the like is disclosed. The security element incorporates a reflective-type diffraction grating, which grating comprises a continuous layer of reflecting material on which is deposited a layer of dielectric material. Non-continuous reflecting layer portions are embedded in the dielectric material. It is practically impossible to lay bare the diffraction grating without destroying it.Type: GrantFiled: December 14, 1984Date of Patent: May 5, 1987Assignee: LGZ Landis & Gyr Zug AGInventor: David L. Greenaway
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Patent number: 4631222Abstract: A hot embossing foil includes, besides a magnetic layer, a layer which has a structure producing a diffraction effect such as a hologram. The foil may also be provided with a signing layer which in the operational condition of the foil is at the exposed surface thereof to which writing can thus be applied, while nonetheless permitting detection of the diffraction-effect structure.Type: GrantFiled: May 16, 1985Date of Patent: December 23, 1986Assignee: Messrs. Leonhard Kurz GmbH & Co.Inventor: Helfried Sander
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Patent number: 4631223Abstract: An embossing foil includes a layer which can be written upon, together with a magnetic layer for data storage purposes. Between the magnetic layer and the writing layer, the foil has a layer with a barrier effect to prevent the writing layer from being attacked by solvent contained in the magnetic layer. The foil may further comprise between the magnetic and writing layers, a structure producing an optical diffraction effect such as a hologram, with the writing surface and said structure being so arranged that nonetheless said structure can still be read, including by machine.Type: GrantFiled: May 16, 1985Date of Patent: December 23, 1986Assignee: Messrs. Leonhard Kurz GmbH & Co.Inventor: Helfried Sander
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Patent number: 4629647Abstract: An embossing foil includes a signing layer which can be written upon, in conjunction with a layer having a structure giving an optical diffraction effect such as a hologram. The signing layer may be clear in the region over the diffraction structure or alternatively the signing layer, over the diffraction structure, may be of a patterned or grid configuration defining openings through which the structure therebeneath can be viewed. The foil may also include a magnetic layer for the storage of variable data which can be readily accessed.Type: GrantFiled: May 16, 1985Date of Patent: December 16, 1986Assignee: Leonhard Kurz GmbH & Co.Inventor: Helfried Sander
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Patent number: 4627642Abstract: The present invention relates to a method for deterring fraud with documents having monetary value such as a PVC substrate having a signature location on the substrate. In the method, a supporting ink layer 2 including a pigment and containing a product that assures it a certain porosity with respect to the substrate is deposited on the signature location; then a transparent, porous varnish layer 3 including a dissolved powder enabling a fluorescence of the desired color to be obtained under ultraviolet light is deposited on certain zones of the first ink layer 2; next a filigree pattern is printed in zones of either the first ink layer 2 or the varnish layer 3, using a silkscreening process and a second pigmented vinyl ink 4. The signature or identifying mark of the owner of the document is executed using a felt-tip pen having an indelible ink, of the type which is indelible to a product such as that sold under the mark "CORRECTOR".Type: GrantFiled: September 5, 1985Date of Patent: December 9, 1986Assignee: Sotimag (SARL)Inventors: Georges Peronneau, Bernard Chalus
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Patent number: 4618402Abstract: The paper according to the invention contains a non-fluorescent means against chemical falsification, reacting to the oxidizing agent/reducing agent couple. The paper according to the invention contains iron(III) and a product giving a complex colored with iron(II). Any attempt to falsify by chemical means provokes the reduction of the iron(III) into iron(II) immediately followed by the formation of the colored complex. According to the invention, the complexing agent is preferably 2,2-bipyridyl. Another complexing agent is orthophenantroline.Type: GrantFiled: July 24, 1985Date of Patent: October 21, 1986Assignee: Arjomari-PriouxInventor: Michel Camus
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Patent number: 4614367Abstract: Improvements in tamper-resisting multipart negotiable instruments, such as airline ticket books are disclosed. The books include at least two webs. The first web includes, on its second surface, a medium for transferring an image to the first surface of a second web in contact therewith when a corresponding image is inscribed on the first surface of that web. The first surface of the second web is in contact with the second surface of the first web and includes an image receiving layer capable of receiving an image transferred from the second surface of the first web. The image receiving layer includes a particulate mixture erasably bonded to the second web, which becomes defaced when rubbed with an organic solvent, and which is removable when an adhesive tape is applied to the image receiving layer and is pulled away therefrom.Type: GrantFiled: December 20, 1984Date of Patent: September 30, 1986Assignee: Rand McNally & Co.Inventor: Thomas J. Breen
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Patent number: 4608288Abstract: A label or seal consists of a transparent base foil having an adhesive layer on one side. An intermediate layer or film is applied to the side having the adhesive layer, adhesion between the base foil and the intermediate layer being decreased in some regions. A cover foil is provided which, with its adhesive layer, is laminated onto the other side of the base foil. The cover foil is irreversibly stretchable under tension and/or easily breakable. Further, a safety rim is formed by a portion of the cover foil which extends past the periphery of the base foil.Type: GrantFiled: August 21, 1984Date of Patent: August 26, 1986Assignees: Joachim Dudzik, Winfried DudzikInventor: Heinz Spindler
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Patent number: 4462039Abstract: This invention relates to a plastic identification card with an improved signature panel. There is a problem with existig credit cards in that the existing signature can be obscured by printing over with a patch of clay composition similar to that used to provide the original signature panel. A new signature can then be applied. This problem is overcome by providing a signature panel which is sandwiched between the core stock and a protective transparent film. The signature panel comprises a layer of chemicals reactive under the pressure of a signature to release a colored dye conforming with the signature.Type: GrantFiled: November 8, 1982Date of Patent: July 24, 1984Assignee: British American Bank Note Inc.Inventors: Edward A. Small, Geoff C. Wright
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Patent number: 4452843Abstract: Security papers with luminescing authenticity characteristics built in or printed thereon which absorb in the visible region of the optical spectrum but in the infrared have a transparent region in which the luminophore also emits. By the absorption in the visible undesired parasitic emissions are suppressed which would make the luminophore visually evident on corresponding excitation. For testing the authenticity of the document the emission is investigated in the infrared. Suitable luminophores are rare earth metal luminophores in suitable host lattices, particularly in ferrite lattices or garnet lattices, which contain transition metal ions as absorbing elements.Type: GrantFiled: October 23, 1981Date of Patent: June 5, 1984Assignee: GAO Gesellschaft fur Automation und Organisation mbH.Inventors: Wittich Kaule, Gerhard Schwenk, Gerhard Stenzel
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Patent number: 4451521Abstract: Security paper with luminescing authenticity characteristics which after excitation with invisible light emit exclusively invisible light of different wavelengths as authenticity signal. The luminophores can be included in the printing ink used or they can be added to the paper material in the manufacture of the paper material. A corresponding test apparatus makes it possible to check the authenticity of the security paper in the presence of customers but unnoticed by them; thereby the invisibility of the test signal and the authenticity signal are taken advantage of and the test device is hidden behind a plate non-transmissive for visible light which however is transmissive for the test signal and for the authenticity signal.Type: GrantFiled: October 23, 1981Date of Patent: May 29, 1984Assignee: Gao Gesellschaft fur Automation und Organisation mbHInventors: Wittich Kaule, Gerhard Stenzel
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Patent number: 4428997Abstract: Protective coatings for securing documents from alteration comprising a noncohesive adhesive layer integrated with a verification feature and a method for applying such coatings.Type: GrantFiled: December 26, 1979Date of Patent: January 31, 1984Assignee: Polaroid CorporationInventor: Joseph Shulman
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Patent number: 4411946Abstract: 7-Hydroxy-coumarin compounds of the general formula ##STR1## wherein A represents a heterocyclic radical, which can contain non-ionic substituents customary in dye-stuff chemistry,R represents hydrogen or cyano andZ represents oxygen or NH andthe ring B can be further substituted non-ionically,are used for impregnating paper, in particular paper which has to be made forgery-proof.Type: GrantFiled: December 22, 1981Date of Patent: October 25, 1983Assignee: Bayer AktiengesellschaftInventor: Horst Harnisch
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Patent number: 4401692Abstract: Transfer-printing supports, which are impregnated or printed with a formulation containing a mixture of a blue disperse dyestuff which sublimes readily and has the formula ##STR1## in which X is hydrogen or halogen, R, R.sup.1 and R.sup.2 denote alkyl with 1 to 4 carbon atoms and R.sup.3 denotes hydrogen or alkyl with 1 to 4 carbon atoms, and yellow to red disperse dyestuffs which sublime readily, give deep and fast black dyeings on polyester materials and polyester mixed materials by the heat transfer-printing process.Type: GrantFiled: July 31, 1981Date of Patent: August 30, 1983Assignee: Hoechst AktiengesellschaftInventors: Rudolf Schickfluss, Manfred Schneider, Claus Schuster
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Patent number: 4335172Abstract: A pressure sensitive label strip comprises a tape-like strip of label material that is overlaid on a tape-like strip of backing material. Parting cut lines extend transversely across the strip of label material at regular intervals to form a plurality of unit label pieces. Feeding cut lines are defined in the effective portions of each unit label piece except the marginal portion of the label piece to form first feeding tongues. Other feeding cut lines are defined in the backing material at the positions corresponding to the abovementioned feeding cut lines to form second feeding tongues which are of a different shape from that of the first feeding tongues.Type: GrantFiled: November 13, 1979Date of Patent: June 15, 1982Assignee: Kabushiki Kaisha SatoInventor: Yo Sato
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Patent number: 4325196Abstract: A laminated multi-layer identification card comprising a plurality of individual layers connected to one another and having at least one outer surface which is directly contactable. At least one additional outer layer is laminated to the outer surface and covers a portion of the outer surface. The outer layer has a surface relief pattern in the form of intaglio printing which is directly accessible. The outer laminated layer may be made of paper and the remaining exposed outer surface not covered by the outer layer may be given a texture similar to that of paper so that the entire surface of the card feels like a paper-rough surface.Type: GrantFiled: February 15, 1980Date of Patent: April 20, 1982Assignee: G.A.O. Gesellschaft fur Automation und Organisation mbHInventors: Wolfgang Gauch, Joachim Hoppe, Yahya Haghiri-Tehrani
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Patent number: 4322466Abstract: The invention relates to a developable surface comprising a carrier layer having thereon at least two deposits of one or more invisible inks in adjacent or overlapping relationship, said deposits in the developed state being unresolvable.Type: GrantFiled: December 4, 1978Date of Patent: March 30, 1982Assignees: Lockley Services Pty. Ltd., Graham Charles Barry, Norman John FieldInventor: Roderick P. J. Tomlinson
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Patent number: 4265469Abstract: Disclosed is a protected document such as a negotiable instrument, a title instrument, indentification document or other documents which should be kept secure from illegal copying by color copiers. The method of making the document comprising preprinting a "VOID" or other warning or cancellation phrase pattern in half tone or multitone on the document and camouflaging this pattern is also disclosed.Type: GrantFiled: May 18, 1977Date of Patent: May 5, 1981Assignee: Burroughs CorporationInventors: William H. Mowry, Jr., Michael J. McElligott, Victor J. Tkalenko, Jr., Joseph Baran
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Patent number: 4239832Abstract: The present invention relates to an ink formulation which may be coated on a flexible substratum to produce a typewriter ribbon or the like, wherein impressions made from such a ribbon are capable of adhesive removal shortly after being created on all conventional typing bonds and papers, but which impressions exhibit delayed alteration resistance whereby any attempt at correcting or removing the indicia by pressure sensitive adhesive means or altering the indicia by erasing will leave an obvious and permanent indication that a removal was attempted.Type: GrantFiled: November 30, 1978Date of Patent: December 16, 1980Assignee: Eaton Allen Corp.Inventors: Victor Barouh, George Rottmann, Salvatore DeSimone
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Patent number: 4210346Abstract: Disclosed is a protected document such as a negotiable instrument, a title instrument, identification document or other documents which should be kept secure from illegal copying by color copiers. The method of making the document comprising preprinting a "VOID" or other warning or cancellation phrase pattern in half tone or multitone on the document and camouflaging this pattern is also disclosed. The document bears a watermark which adds to the security of the system.Type: GrantFiled: June 23, 1977Date of Patent: July 1, 1980Assignee: Burroughs CorporationInventors: William H. Mowry, Jr., Michael J. McElligott, Victor J. Tkalenko, Jr., Joseph Baran, Curtis W. Ingalls
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Patent number: 4210688Abstract: A pressure sensitive label strip comprising a tape-like strip of label material that is overlaid on a tape-like strip of backing material; parting cut lines extend transversely across the strip of label material at regular intervals so as to form a plurality of unit label pieces; feeding cut lines in the strip of backing material define a plurality of feeding tongues having their connected portions oriented in the direction of forward motion of the label strip, and the feeding tongues are at positions that either correspond to the positions of the pairs of feeding cut lines of the label material or that roughly correspond.Type: GrantFiled: July 20, 1978Date of Patent: July 1, 1980Assignee: Kabushiki Kaisha SatoInventor: Yo Sato
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Patent number: 4161551Abstract: An ink formulation which may be coated on a flexible substratum to produce a typewriter ribbon or the like, wherein the impression made from such a ribbon is capable of adhesive removal shortly after being created on all conventional typing papers, but which impression exhibits delayed alteration resistance whereby any attempt at correcting or removing the indicia by pressure sensitive adhesive means or, altering the indicia by erasing and the like, will leave an obvious and permanent indication that a removal was attempted.Type: GrantFiled: March 24, 1977Date of Patent: July 17, 1979Assignee: Eaton Allen Corp.Inventors: Victor Barouh, George Rottmann, Salvatore DeSimone
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Patent number: 4152476Abstract: A laminate blank suitable for use in making a credit or identification card is disclosed. It consists essentially of, in order, a surface carrier film, a magnetic coating and a card substrate. The surface carrier and magnetic coating comprose a unitary transfer tape. The card substrate is bonded to the magnetic coating by means of a strong adhesive. In contrast, the carrier film and magnetic coating of the tape are relatively very weakly united. This construction facilitates application of the requisite magnetic coating to the surface of the eventual card, and permits ready access to such coating through simple mechanical removal of the tape carrier film of the blank.Type: GrantFiled: March 4, 1977Date of Patent: May 1, 1979Assignee: Champion International CorporationInventor: Nathan Stillman
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Patent number: 4143891Abstract: The negotiable document which may be used, e.g. by airlines includes a cover sheet provided with a hot spot carbon or other image transfer medium and at least one underlying sheet fully or partly coated with microcapsules of a dye intensifier and attractor. When information is imprinted on the cover sheet, the microcapsules of the dye intensifier in the underlying sheet are burst to wet the sheet and, thus, allow impregnation of the image transferred by the hot spot carbon into the fibers of the sheet. At the same time, the dye within the hot spot carbon is attracted into the sheet. The impregnation of the sheet is sufficient to prevent removal of the image from the underlying sheet without first destroying the sheet or mutilating it in such a manner that the defalcation effort is obvious.Type: GrantFiled: December 29, 1976Date of Patent: March 13, 1979Assignee: Transkirt CorporationInventor: Frank Neubauer
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Patent number: 4121961Abstract: A method of label installation employing two sheets suitably coated to produce an image on the underside of the upper transparent sheet and thereafter applying the upper sheet to a label receiving surface.Type: GrantFiled: April 18, 1977Date of Patent: October 24, 1978Inventors: Jerome J. Brunette, William G. Fogleson
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Patent number: 4098940Abstract: The present invention is related to a sheet or a composite sheet made of transparent thermoplastics with optical inhomogeneities according to a desired and reproducible pattern, which are not discernible with an unaided eye, and which produce polarization-optical patterns when placed in a polarization-optical arrangement. The invention is further related to a process for the manufacture of such a sheet or composite sheet and to their use for the manufacture of counterfeit-proof official documents.Type: GrantFiled: August 31, 1976Date of Patent: July 4, 1978Assignee: Hoechst AktiengesellschaftInventors: Rudolf Groh, Gustav Meinel