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
  • B41M3/142—Security printing using chemical colour-formers or chemical reactions, e.g. leuco-dye/acid, photochromes
• • 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
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M5/00—Duplicating or marking methods; Sheet materials for use therein
  • B41M5/26—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used
  • B41M5/28—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used using thermochromic compounds or layers containing liquid crystals, microcapsules, bleachable dyes or heat- decomposable compounds, e.g. gas- liberating
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M5/00—Duplicating or marking methods; Sheet materials for use therein
  • B41M5/26—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used
  • B41M5/28—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used using thermochromic compounds or layers containing liquid crystals, microcapsules, bleachable dyes or heat- decomposable compounds, e.g. gas- liberating
  • B41M5/282—Thermography ; Marking by high energetic means, e.g. laser otherwise than by burning, and characterised by the material used using thermochromic compounds or layers containing liquid crystals, microcapsules, bleachable dyes or heat- decomposable compounds, e.g. gas- liberating using thermochromic compounds
  • B41M5/284—Organic thermochromic compounds
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
  • G03C5/00—Photographic processes or agents therefor; Regeneration of such processing agents
  • G03C5/56—Processes using photosensitive compositions covered by the groups G03C1/64 - G03C1/72 or agents therefor
• • Y—GENERAL 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
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S430/00—Radiation imagery chemistry: process, composition, or product thereof
  • Y10S430/146—Laser beam
• • Y—GENERAL 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
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S430/00—Radiation imagery chemistry: process, composition, or product thereof
  • Y10S430/163—Radiation-chromic compound

Definitions

• the invention relates to the field of printing and relates, more particularly, to the printing of an apparent thermoplastic or thermosetting polymerized layer of a portable information carrier body.
• printing should be considered, in the present invention, in a broad sense, as being a technique in which an action is exerted on an object so as to leave a visible mark on said object.
• the portable information medium can be arbitrary. However, these are in particular standard information carriers in smart card format to which reference will be made in the description which follows.
• Smart cards and, more generally, memory cards comprise a thermoplastic or thermosetting card body formed from one or more layers. Two faces of said body are visible. These faces show a drawing, a logo, a photographic reproduction as well as, very often, written information printed in series according to various known methods.
• Certain printing methods involve a simple deposit of conventional ink.
• Other methods generally faster and more precise, involve lasers.
• methods are known in which a colored ink is heat transferred by means of a laser and from a heat-resistant transfer film applied to one face of the polymerized card body.
• a card body is obtained showing a colored pattern according to the path of the laser radiation on the film or films.
• processes called indirect, require the intermediary of a film from which the inks will diffuse and are therefore slow.
• the definition of the pattern obtained is poor.
• a determined area of an upper layer of a multilayer card body is removed by means of a YAG laser adjusted so as to emit electromagnetic radiation in the infrared. that an underlayer of said body, the color of which is different from that of the upper layer, appears. With several superimposed layers of different colors, it is possible to obtain a multicolored card body whose pattern is defined by a directed scanning of the laser radiation.
• Still other methods propose either an evaporation of particular areas of the surface of the card body, or a foaming of said areas.
• This evaporation or foaming is induced by the heat given off by laser radiation. Evaporation leaves a hole and can reveal a colored undercoat of the card body.
• the foaming changes the nature of the surface of the card body which for example shows differences in the refractive index at the origin of the patterns. These processes are generally slow and the definition of the pattern, as well as its contrast, are poor.
• the surface of the card body does not remain intact.
• so-called whitening methods propose a directed and selective destruction of pigments or other colored molecules contained in a layer of the card body by a laser whose radiation is emitted in the visible range.
• the color appears negatively.
• two laser irradiations are necessary. For example, to make blue appear on the surface of a black layer of a card body comprising at the same time blue, red and yellow pigments, two laser rays locally destroy one, the red pigments, the other , yellow pigments. If it is desired to obtain white, the black layer of the card body is irradiated with three laser radiations of different wavelengths. These processes are slow since obtaining a color at a given point requires several irradiations.
• the white obtained is imperfect since the destruction of the pigments or colored molecules is never total. and, in practice, it is found that the colors obtained are pale.
• a problem which the invention proposes to solve is to propose a new process for serial printing of a polymerized thermoplastic or hardenable visible layer of a portable information carrier body, which is rapid and which leaves the surface of said layer intact.
• the claimed solution of the invention relates to a process for printing a visible polymerized thermoplastic or hardening layer of a portable information carrier body, characterized in that it comprises the following stages: 'a polymerizable thermoplastic or hardenable binder, and at least one photochromic compound sensitive to laser radiation of given wavelength so as to pass from a first state to a second colored state, in order to form a mixture;
• the procedure is positive: the appropriate photochromic compound is irradiated with a single laser radiation of selected wavelength.
• the subject of the invention is a portable information medium comprising a polymerized thermoplastic or hardened printed layer. visible from a support body, characterized in that said polymerized layer comprises: a thermoplastic or hardenable polymerized binder; and - at least one photochromic compound fixed in a second colored state obtained from a first state by irradiation with laser radiation of given wavelength.
• Chip cards mainly comprise a micromodule included in a card body.
• the micromodule consists of an integrated circuit chip connected to metal studs forming flush metallizations on the surface of the card body and / or to an antenna embedded in said body. Depending on whether the micromodule is connected to an antenna or to studs, the smart card is said, respectively, to operate without contact or to operate with contacts. If the card has two operating modes, it is said to be hybrid.
• the card body is a rectangular parallelepiped of small thickness whose dimensions, as defined in particular by standard 7810, are of the order of 85 mm in length, 54 mm in width and 0.76 mm in thickness.
• the card body therefore shows six faces including two large parallel and flat faces. It consists of one or more superimposed layers, a layer of said body appearing on each of the large faces. These visible layers are printed and show any pattern, whether colored or not. They may be covered with a transparent protective film.
• the different layers of the card body and, in particular, the visible layers of said body are polymerized with thermoplastic or thermo or photo-hardening. They therefore comprise a polymer of one or more monomers.
• Polymers are for example: acrylonitrile-butadiene-styrene (ABS), polycarbonate (PC), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polymethylmethacrylate (PMMA), or any other polymeric derivative of acrylic or methacrylic system.
• the layer or layers of the card body are white or whitish in color. This color can be improved by adding, in the composition of the card body, a mineral filler, for example, calcium carbonate or titanium dioxide. Note that the white color is not limiting and that certain card bodies are, before printing, colored or even transparent in the case of a PMMA card body for example.
• the printing process of the invention comprises different stages.
• a first step relates to a liquid phase mixture of at least one polymerizable binder, at least one photochromic compound and, advantageously at least one reacti-f.
• the mixture obtained is liquid, more or less viscous.
• the polymerizable binder is a binder intended to form the polymerized structure or polymer network of the visible layer or layers of the card body and of the other layers of said body. It comprises one or more monomers or oligomers, one or more polymers, a reagent for the polymerization of said monomers or oligomers, a reagent intended for polymerization or even for post-polymerization of polymers, as well as various other compounds or additives, for example a mineral filler for bleaching the card and a solvent.
• Photochromic compounds are compounds capable of undergoing a reversible transformation induced by electromagnetic radiation between two states having different absorption spectra.
• a first state is characterized by a first absorption spectrum which comprises at least one absorption band and a second state is characterized by a second absorption spectrum which also includes at least one absorption band.
• the photochromic compounds are normally colorless and their absorption spectrum does not belong to the visible range, that is to say to the range whose wavelengths are between 400 and 780 nm.
• an absorption band of said spectrum is located outside the visible range, in the Ultra-Violet range, that is to say in the range whose wavelengths are between 20 and 400 nm.
• said band lies in a range from 200 to 400 nm.
• electromagnetic radiation whose wavelength is in the aforementioned absorption band is likely to cause a transformation of the photochromic compound, from the first state to the second.
• This transformation can be unimolecular or bimolecular.
• the transition time from the first state to the second is very short, less than a value of the order of 20 ns., In an example from 40 to 50 ps. for spironaphtooxazines.
• the photochromic compounds In their second state, the photochromic compounds absorb part of the light they receive, since their absorption spectrum includes, in this second state, bands located in the visible range. Said photochromic compounds therefore appear colored.
• the transformation is reversible and, since the second state is metastable, a photochromic compound in its second state is likely to transform in its first more stable state.
• said compounds are either photoreversible, or thermoreversible, or photothermoreversible, or multiphotochromic or electrochemical.
• the photochromic compounds of the invention can be simply dissolved in the solvent of the mixture or advantageously contained in micro-particles or micro-capsules which dissolve in said solvent, thus releasing said compounds in the mixture. They are soluble in the polymerizable binder. To this end, chains, for example hydrophilic, can advantageously be grafted onto said compounds.
• the mixture of the invention comprises three different colorless photochromic compounds: a first, a second and a third compound.
• the first compound appears, in its second state, yellow or green
• the second compound appears, in its second state, magenta red
• the third compound appears, in its second state, cyan blue.
• we choose these compounds so that, in the mixture, the absorption band of the first compound in its first state is sufficiently distinguished from the absorption band of the second compound in its first state, said bands being further distinguished from the band absorption of the third compound in its first state.
• Photochromic compounds which can advantageously be used in the process of the invention, are bi or polycyclic spirannic compounds having a carbon atom common to two rings: the spirannic atom.
• spirooxazines and spiropyranes and derivative compounds react, under the effect of electromagnetic radiation h, according to the following reaction:
• the cycles of the spiran atom of spirooxazines and spiropyranes are distributed in space orthogonally and appear colorless.
• these cycles form a plane and appear colored.
• these compounds have the property of being able to be mixed in a polymeric medium while retaining, in such a medium, their photochromic properties.
• said properties can be modified, and, in particular, one can observe, on the colored form of the second state, hypsochromic or bathochromic effects which can go up to 80nm.
• photochromic compounds can be used. These are, for example, chromenes whose general formulas are of the type:
• the reagent (s) are intended to fix the second colored state and the colored state only of the photochromic compound (s) present in the mixture and only this second colored state.
• these are salts of divalent metals such as Mn 2+ , Ni 2+ , Zn 2 +, Ca 2+ , Pb 2+ , Cd 2+ , Mg 2+ , Co 2+ , Cu 2 + generally associated with a mineral counter ion of the type
• additives for example solvents, making it possible to separate the spectra and the absorption bands of the photochromic compounds present in the mixture so that laser radiation acts on a given photochromic compound and only on this photochromic compound without the possibility of interference.
• the mixture obtained, comprising the photochromic compounds is then, according to the invention, spread on a support for manufacturing the layer to be printed on the card body.
• This support consists, in one example, of a bottom and lateral sides forming a frame.
• This cavity can contain one or more polymerized or prepolymerized layers or sublayers of the card body as well as, optionally, a micromodule inserted in said layers or sublayers.
• the mixture spilled on the support for manufacturing the layer to be printed is then irradiated with laser electromagnetic radiation, the length of which is wave belongs to the UV range and, preferably, to the range extending from 200 to 400 nm, and corresponding to an absorption band of one and only one photochromic compound present in the mixture, so that said compound turns into the colored form of its second state.
• the power of the laser irradiations can be modulated, in particular as a function of the wavelength, so that, for example, the photochromic response is itself modulated, the colors obtained therefore being nuanced.
• the mixture comprises n different photochromic compounds where n is an integer
• it can be irradiated by n laser radiation, each laser radiation having a given wavelength capable of inducing the transformation of one and only one photochromic compound among the n compounds.
• the n photochromic compounds are respectively and only sensitive to the n wavelengths of the laser radiation irradiating the support.
• the irradiation is carried out by three rays of length d wave different from the UV range, in particular from the above range from 200 to 400 nm, a first radiation being at the origin of the transformation of the first compound into its green or yellow form, a second radiation being at the origin of the transformation of the second compound in its magenta red form and a third radiation being at the origin of the transformation of the third compound in its cyan blue form.
• the print is then polychromic.
• the irradiation is carried out by laser radiation, successively or simultaneously.
• the irradiation is carried out point by point, by a laser beam of determined diameter, or then, through a filter.
• the relative displacement of the laser radiation relative to the layer to be printed on the card body different cases are possible: either the support for manufacturing the layer moves relative to the laser radiation which retains a fixed position, or the radiation laser move relative to said fixed support, that is to say the manufacturing support and the laser radiation move at the same time. These trips are controlled and coordinated by a computer with suitable software.
• the irradiation is carried out before or after a step of pre-polymerization or of polymerization of the widespread mixture and / or of evaporation of the solvent, in the case of thermoplastics. Also, depending on the case, the irradiation is carried out on the mixture spilled in a more or less viscous liquid state, or else in a pre-polymerized solid state, that is to say partially polymerized, or polymerized.
• the polymerization and / or evaporation step of the solvent has not been carried out before the irradiation, it is carried out afterwards.
• This polymerization can be supplemented by a post-polymerization or post-crosslinking which results in the production of crosslinked, interpenetrated or semi-interpenetrated networks, from a combination of two types of successive reactions proceeding from different mechanisms.
• Another step in the process of the invention is the irreversible fixing of the photochromic compounds in their second colored state, so that the printing pattern is preserved and cannot, in particular, change with the sun. Return to the original transparent form is thus prevented.
• This fixing is carried out, for example, by the fixing reagent.
• a spirooxazine, spironaphtooxazine is blocked, in its second state, by a metal complex Zn 1/2 C0 2 ROH in the following manner:
• the colorless form of the photochromic compounds which have not changed state is fixed, irreversibly.
• This fixation can be carried out by a reagent.
• very short UVs of the order of 100 nm, allow the bonds to be destroyed.
• the power of UV can be modulated so as to modulate the fixation of the colorless form of the photochromic compounds.
• Definitive fixation or blocking of colored and non-colored forms of photochromic compounds can be achieved or improved by polymerization or post-polymerization of the mixture, for example, under the effect of UV exposure of short wavelength. This UV exposure can also trigger blocking by the fixing reagents without triggering post-polymerization.
• the above fixing and / or blocking steps can be carried out at the same time.
• the blocking of the colored and non-colored forms can moreover be simply mechanical, by evaporation of the solvents.
• the printed patterns do not show degradation over time or under the effect of heat or light.
• Post-polymerization can be localized. It will displace products and will be the source of a difference in refractive index, the product then appearing in polychromic relief.
• the printed board can be dried with evaporation of solvents so as to obtain a finished product.
• the method of the invention it is possible to print, directly and positively, about 20,000 visible layers or card faces per hour, which remain intact after printing.
• the definition of printed patterns is, in theory, molecular. In practice, it is limited, in the case where the irradiation is carried out through a filter, to the dimensions of the frame of said filter and, in the case where the irradiation is carried out point by point, to the dimensions of the beam to be the surface of the irradiated layer.

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• Physics & Mathematics (AREA)
• Optics & Photonics (AREA)
• General Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Credit Cards Or The Like (AREA)
• Non-Silver Salt Photosensitive Materials And Non-Silver Salt Photography (AREA)
• Laminated Bodies (AREA)
• Thermal Transfer Or Thermal Recording In General (AREA)

Applications Claiming Priority (3)

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• 1996
  • 1996-06-11 FR FR9607240A patent/FR2749673B1/fr not_active Expired - Lifetime
• 1997
  • 1997-06-11 KR KR1019980710178A patent/KR20000016583A/ko not_active Application Discontinuation
  • 1997-06-11 US US09/202,425 patent/US6107010A/en not_active Expired - Lifetime
  • 1997-06-11 BR BR9709705A patent/BR9709705A/pt active Search and Examination
  • 1997-06-11 JP JP50130398A patent/JP3416148B2/ja not_active Expired - Lifetime
  • 1997-06-11 AT AT97928333T patent/ATE190735T1/de not_active IP Right Cessation
  • 1997-06-11 CA CA002268786A patent/CA2268786A1/fr not_active Abandoned
  • 1997-06-11 WO PCT/FR1997/001044 patent/WO1997048016A1/fr not_active Application Discontinuation
  • 1997-06-11 CN CNB971972273A patent/CN1179242C/zh not_active Expired - Lifetime
  • 1997-06-11 ES ES97928333T patent/ES2147003T3/es not_active Expired - Lifetime
  • 1997-06-11 HU HU0002137A patent/HUP0002137A3/hu unknown
  • 1997-06-11 EP EP97928333A patent/EP0912916B1/de not_active Expired - Lifetime
  • 1997-06-11 DE DE69701468T patent/DE69701468T2/de not_active Expired - Lifetime

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