Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M3/00—Printing processes to produce particular kinds of printed work, e.g. patterns
  • B41M3/14—Security printing
  • B41M3/144—Security printing using fluorescent, luminescent or iridescent effects
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M3/00—Printing processes to produce particular kinds of printed work, e.g. patterns
  • B41M3/14—Security printing
  • B41M3/146—Security printing using a non human-readable pattern which becomes visible on reproduction, e.g. a void mark
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
  • D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
  • D21H21/40—Agents facilitating proof of genuineness or preventing fraudulent alteration, e.g. for security paper
  • D21H21/44—Latent security elements, i.e. detectable or becoming apparent only by use of special verification or tampering devices or methods
  • D21H21/48—Elements suited for physical verification, e.g. by irradiation

Definitions

• the present invention relates to a composition of anti-copy marking.
• An object of the invention is to propose a composition anti-copy marking causing degradation color when making a photocopy and whose reproduction is not easily achievable.
• a copy marking composition comprising an organic matrix into which are incorporated photoluminescent components of which at least a has a material color visible in the light of day, this composition comprising at least a first photoluminescent component having luminescence in a first range of wavelengths perceptible by sensors of a copier when it is energized by a photocopier lamp, and at least one second component photoluminescent having luminescence in a second wavelength range perceptible by the sensors from the photocopier when excited by a lamp the second range of wavelengths being at least partially different from the first wavelength range and the luminescence of at least one of the components having sufficient intensity to be perceived by the photocopier's sensors according to a perception different from that obtained when this same component is exposed to daylight.
• the mixture of different photoluminescent components makes it difficult to reproduce the composition and because of the difference in intensity and spectrum of illumination of a photocopier lamp by compared to daylight, the relative intensity of the light color (luminescence) versus color matter (refracted radiation) is different from that obtained during exposure to daylight from so that the color reproduced during a photocopy is significantly different from that appearing on the document original during a light analysis.
• the first photoluminescent component and the second component photoluminescent form a light cascade. Range second component luminescence wavelengths is thus modified so that the color drift is increased when photocopying.
• the composition comprises a phosphorescent luminescent component.
• the luminescence that continues beyond excitement by the photocopier lamp then causes on the photocopier sensors an additional disturbance increasing the difficulty of color management by the photocopier.
• the copy marking composition according to the invention comprises in an organic matrix formed for example with an acrylic resin binder and a mixture photoluminescent representing approximately 20% by weight of the composition, the photoluminescent mixture comprising a part of zinc sulfide doped with silver, a part of copper-doped zinc sulfide and a portion of calcium doped with europium and samarium.
• zinc sulfide doped with silver is a fluorescent component, i.e. its luminescence immediately ceases with cessation of excitement and forms a luminous cascade with the sulfide of calcium doped with europium and samarium, i.e. that part of the luminescence resulting from the sulfide of zinc doped with silver (around 10%) corresponds to the spectrum excitation of calcium sulfide which is also a fluorescent component.
• Copper-doped zinc sulfide is a component phosphorescent whose luminescence forms very partially a luminous cascade with calcium sulfide doped with europium and samarium.
• the luminescence of silver-doped zinc sulfide is blue in color, the luminescence of copper doped zinc is pale green in color and the luminescence calcium sulfide doped with europium and samarium is red.
• the composition is subject to daylight, it appears pink and when a sign printed using this composition is reproduced by a photocopier, this sign appears yellowish on the photocopy.
• photoluminescent components can be used not forming a light cascade or whose only some of them form a luminous cascade. It is also possible to produce a composition containing exclusively fluorescent components, for example limiting the composition described above to a mixture silver doped zinc sulfide and calcium doped with europium and samarium.
• the doped calcium sulfide to the europium and to the samarium emits a luminescence to the times in a downward conversion, forming a luminous cascade with zinc sulfide doped with silver, and according to a backward conversion (anti-Stokes conversion) from the infrared which is emitted so important by the lamp of a photocopier.
• This conversion ascending can be accentuated by using off the excited neodymium doped yttrium vanadate by ultraviolet and emits in the infrared and thus forms a second luminous cascade with the sulfide calcium.
• oxysulphides of rare earth which have a downward or upward conversion depending on the dopant used.

Landscapes

• Life Sciences & Earth Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• Luminescent Compositions (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=8866523

Family Applications (1)

Country Status (6)

Cited By (1)

Citations (4)

Family Cites Families (9)

• 2001
  • 2001-08-14 FR FR0110805A patent/FR2828697B1/fr not_active Expired - Fee Related
• 2002
  • 2002-08-07 EP EP02291985A patent/EP1284321A1/de not_active Withdrawn
  • 2002-08-08 MD MDA20020204A patent/MD2402C2/ro not_active IP Right Cessation
  • 2002-08-09 MA MA26767A patent/MA25710A1/fr unknown
  • 2002-08-12 TN TNSN02073 patent/TNSN02073A1/fr unknown
  • 2002-08-14 OA OA1200200245A patent/OA12477A/fr unknown

Patent Citations (4)

Also Published As

Similar Documents

Legal Events