JP5928406B2 - Anti-counterfeit recording body, method for identifying forgery thereof, and method for producing the same - Google Patents

Description

  The present invention relates to an anti-counterfeit recording material that utilizes a reaction between a dye precursor and a developer, and a portion colored by thermal energy from a thermal head or a thermal stamp exhibits a fluorescent reaction. .

  The number of cases in which information sheets are used for voting tickets and tickets such as tickets is increasing. In order to prevent forgery, these sheets have been introduced with anti-counterfeiting techniques such as providing a management bar code for identifying individual ticketing information.

  Conventional techniques for preventing counterfeiting related to information paper include a technique for providing a layer containing a fluorescent substance on the heat-sensitive recording layer and the back surface (see Patent Document 1), a technique using a fluorescent pigment or a fluorescent dye (see Patent Document 2). ), Technology for inserting fluorescent fibers and threads into a base paper (see Patent Document 3), technology using a hologram (see Patent Document 4), technology for watermarking a base paper (see Patent Document 5), and latent images appear when copied A technique to be issued (see Patent Document 6) has been proposed. However, these anti-counterfeiting technologies have fixed information for anti-counterfeiting (watermarks, hologram printing, etc.), and for variable information such as ticketing information written on cash vouchers and tickets. In fact, the technology for preventing forgery has not been proposed yet.

Japanese Patent Laid-Open No. 04-193484 Japanese Patent Laid-Open No. 06-166264 JP 2002-264488 A JP 2003-195045 A JP 2003-200634 A JP 2004-163797 A

  The main object of the present invention is to provide an anti-counterfeit recording body having high anti-counterfeiting properties and excellent visibility, a method for identifying the forgery thereof, and a method for producing the same.

  As a result of intensive studies in view of the above-described conventional technology, the present inventors, as a result of heating with a dye precursor having a pyridine skeleton in the molecular structure and a dye precursor having the pyridine skeleton, in at least a part of the thermosensitive coloring portion. By including a forgery preventing part containing a developer that reacts with the colorant to develop the color, the above-mentioned problems have been solved. That is, the present invention relates to the following anti-counterfeit recording material.

  Item 1: A recording medium having a thermosensitive coloring part containing a dye precursor and a developer on at least a part of a support, and having a pyridine skeleton in a molecular structure in at least a part of the thermosensitive coloring part A forgery-preventing part containing a dye precursor and a dye precursor having a pyridine skeleton and a developer that develops color by reacting with heating, and the color image of the forgery-preventing part emits fluorescence under ultraviolet light A forgery-preventing recording material that is recognized as information for authenticity determination.

  Item 2. The anti-counterfeit recording material according to Item 1, wherein the dye precursor having the pyridine skeleton is represented by the following general formula (1).

（式中、Ｒ^１は水素原子もしくは炭素数１〜８のアルコキシ基を表し、Ｒ^２は水素原子もしくは炭素数１〜８のアルコキシ基を表す。Ｒ^１及びＲ^２は同一であっても、異なっていてもよい。Ｒ^３は炭素数１〜４のアルキル基を表す。）

(In the formula, R ¹ represents a hydrogen atom or an alkoxy group having 1 to 8 carbon atoms, R ² represents a hydrogen atom or an alkoxy group having 1 to 8 carbon atoms. Even if R ¹ and R ² are the same, R ³ represents an alkyl group having 1 to 4 carbon atoms.

  Item 3: The dye precursor having the pyridine skeleton is 4- [2- (2-butoxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine, 4- [2- (2-pentyl) Oxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine, 4- [2- (2-hexyloxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine 4- [2- (2-octyloxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine, 4- (2,6-diphenyl-4-pyridinyl) -N, N-dimethyl Benzeneamine, 4- [2,6-bis (2-butoxyphenyl) -4-pyridinyl] -N, N-dimethylbenzenamine, 4- [2,6-bis (2-pentyloxy) Phenyl) -4-pyridinyl] -N, N-dimethylbenzenamine, 4- [2,6-bis (2-hexyloxyphenyl) -4-pyridinyl] -N, N-dimethylbenzenamine, and 4- [2 Item 3. The forgery-preventing recording material according to Item 1 or 2, which is at least one selected from the group consisting of 1,6-bis (2-octyloxyphenyl) -4-pyridinyl] -N, N-dimethylbenzenamine.

  Item 4: The developer contained in the anti-counterfeit part is 4-hydroxy-4′-isopropoxydiphenylsulfone, 4-hydroxy-4′-n-propoxydiphenylsulfone, Np-tolylsulfonyl-p-butoxy Carbonylphenylurea, N- (p-toluenesulfonyl) -N ′-(3-p-toluenesulfonyloxyphenyl) urea, N- (p-toluenesulfonyl) -N′-phenylurea, 4,4′-bis [ Item 4. Any one of Items 1 to 3, which is at least one member selected from the group consisting of (4-methyl-3-phenoxycarbonylaminophenyl) ureido] diphenylsulfone and 4,4′-bis (3-tosylureido) diphenylmethane. The anti-counterfeit recording material described in 1.

  Item 5: The thermosensitive coloring part includes a first dye precursor and a second dye precursor as the dye precursor, the first dye precursor is contained in the form of solid dispersed fine particles, and the first dye precursor, Contains a second dye precursor that develops a different color tone in the form of a composite fine particle containing a second dye precursor and a polymer compound, and one of the first dye precursor and the second dye precursor is the pyridine Item 5. The forgery-preventing recording material according to any one of Items 1 to 4, which is a dye precursor having a skeleton.

  Item 6: The thermosensitive coloring portion has a multilayer structure composed of at least a first thermosensitive recording layer and a second thermosensitive recording layer, and the first thermosensitive recording layer contains a first dye precursor in the form of solid dispersed fine particles. The second thermosensitive recording layer contains a second dye precursor in the form of a composite fine particle containing a second dye precursor and a polymer compound, and one of the first dye precursor and the second dye precursor. Item 6. The anti-counterfeit recording material according to any one of Items 1 to 5, wherein is a dye precursor having the pyridine skeleton.

  Item 7: The device according to any one of Items 1 to 6, wherein the forgery prevention part contains an ethylene-acrylic copolymer or includes a coating part that contains an ethylene-acrylic copolymer and is adjacent to the forgery prevention part. Item 2. An anti-counterfeit recording material according to item 1.

  Item 8: The forgery-preventing recording material according to any one of Items 1 to 7, further comprising a thermal transfer receiving layer, an inkjet recording layer, a magnetic recording layer, or an adhesive layer.

  Item 9: A method for determining the authenticity of the anti-counterfeit recording body having the structure according to any one of Items 1 to 8, wherein the anti-counterfeiting portion of the anti-counterfeit recording body is colored while being heated, An anti-counterfeit identification method for anti-counterfeit recording, characterized in that a genuine image and a counterfeit are identified depending on whether or not a color-developed image emits fluorescence when irradiated with ultraviolet rays.

  Item 10: Coating and drying using a coating solution containing a dye precursor having the pyridine skeleton and a dye precursor that reacts with the dye precursor having the pyridine skeleton to cause color development by heating. The process of providing the said forgery prevention part by the above, or the process of providing the said forgery prevention part by forming as a latent image of a suitable character or a figure using the ink containing the said composition. Manufacturing method for forgery prevention.

  The anti-counterfeit recording material of the present invention has a high anti-counterfeit property and is excellent in visibility.

  The present invention is a recording medium having a thermosensitive coloring part containing a dye precursor and a developer on at least a part of a support, and having a pyridine skeleton in the molecular structure in at least a part of the thermosensitive coloring part It includes a forgery prevention unit containing a dye precursor and a dye precursor having the pyridine skeleton and a developer that reacts with heating to develop color. In the forgery prevention unit, a color image having a color tone in the visible light region can be recorded by thermal energy from a thermal head of a printer, a thermal stamp, or the like. At the same time, the color image of the forgery prevention unit is recognized as authenticity determination information that emits fluorescence under ultraviolet light.

  The thermosensitive coloring portion in the present invention may be composed of one or two or more thermosensitive recording layers, or may be composed of one or two or more thermosensitive recording layers formed in a pattern. In the present invention, the forgery prevention part comprising such a heat-sensitive recording layer contains a specific dye precursor. In the forgery prevention unit, at least one of fixed information and variable information, which is information for authenticity determination, can be recorded in advance as a color image. It is also possible to record as a color image when it becomes necessary to identify whether it is a counterfeit or not. In the case of an anti-counterfeit part comprising a heat-sensitive recording layer formed in a pattern, information for authenticity determination is formed as a latent image of appropriate characters or figures determined in advance by printing, etc., and colored by heating It is also possible to make a true / false judgment by visualizing it as an image. The anti-counterfeit recording material according to the present invention has a dye precursor that is colorless or light-colored. Therefore, the anti-counterfeiting portion is colored as necessary without the general user knowing the presence of the forgery-preventing portion. Only when an image emits fluorescence under ultraviolet light is it recognized as information for authenticity determination. In addition, forgery of variable information can be prevented.

  The dye precursor having a pyridine skeleton in the molecular structure in the present invention is represented by the following general formula (1).

（式中、Ｒ^１は水素原子もしくは炭素数１〜８のアルコキシ基を表し、Ｒ^２は水素原子もしくは炭素数１〜８のアルコキシ基を表す。Ｒ^１及びＲ^２は同一であっても、異なっていてもよい。Ｒ^３は炭素数１〜４のアルキル基を表す。）

(In the formula, R ¹ represents a hydrogen atom or an alkoxy group having 1 to 8 carbon atoms, R ² represents a hydrogen atom or an alkoxy group having 1 to 8 carbon atoms. Even if R ¹ and R ² are the same, R ³ represents an alkyl group having 1 to 4 carbon atoms.

In the general formula (1), R ¹ represents a hydrogen atom or an alkoxy group having 1 to 8 carbon atoms which may be branched, and R ² represents a hydrogen atom or an alkoxy group having 1 to 8 carbon atoms which may be branched. R ¹ and R ² may be the same or different, and R ³ represents an alkyl group having 1 to 4 carbon atoms which may be branched, but at least R ¹ and R ² are linear. The saturated hydrocarbon group is preferable because it can be easily introduced industrially.

In the present invention, from the viewpoint of increasing the color density and improving the storage stability and light resistance of the color image, in the general formula (1), either R ¹ or R ² is an alkoxy group having 4 to 8 carbon atoms. Is preferably represented. Furthermore, from the viewpoint of further increasing the color density, it is preferable that either R ¹ or R ² represents a hydrogen atom.

The dye precursor having the pyridine skeleton is 4- [2- (2-butoxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine, 4- [2- (2-pentyloxyphenyl). ) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine, 4- [2- (2-hexyloxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine, 4 -[2- (2-octyloxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine, 4- (2,6-diphenyl-4-pyridinyl) -N, N-dimethylbenzenamine 4- [2,6-bis (2-butoxyphenyl) -4-pyridinyl] -N, N-dimethylbenzenamine, 4- [2,6-bis (2-pentyloxyf) Nyl) -4-pyridinyl] -N, N-dimethylbenzenamine, 4- [2,6-bis (2-hexyloxyphenyl) -4-pyridinyl] -N, N-dimethylbenzenamine, and 4- [2 , 6-Bis (2-octyloxyphenyl) -4-pyridinyl] -N, N-dimethylbenzenamine is preferred. These dye precursors have a more vivid yellowish color tone in the visible light region, and are excellent in fluorescence under ultraviolet light. Further, in the general formula (1), R ¹ and R ² are preferably excluded from the case where they are simultaneously hydrogen atoms from the viewpoint of further increasing the color density. Among these, from the viewpoint of further improving the storability of the color image, 4- [2- (2-butoxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine, 4- [2 -(2-pentyloxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine and 4- [2- (2-hexyloxyphenyl) -6-phenyl-4-pyridinyl] -N One selected from the group consisting of N, dimethylbenzeneamine is preferred.

  As long as the effects of the present invention are not impaired, a desired color tone can be obtained by mixing two or more dye precursors having different color tone in addition to the dye precursor having a pyridine skeleton used in the present invention. You can also.

  Examples of the dye precursor that develops a black color tone include 3-pyrrolidino-6-methyl-7-anilinofluorane, 3-diethylamino-7- (m-trifluoromethylanilino) fluorane, and 3-diethylamino-6. -Methyl-7- (m-methylanilino) fluorane, 3- (N-isoamyl-N-ethylamino) -7- (o-chloroanilino) fluorane, 3- (N-ethyl-p-toluidino) -6-methyl- 7-anilinofluorane, 3- (N-ethyl-N-2-tetrahydrofurfurylamino) -6-methyl-7-anilinofluorane, 3-diethylamino-6-chloro-7-anilinofluorane, 3-di (n-butyl) amino-6-methyl-7-anilinofluorane, 3-di (n-amyl) amino-6-methyl-7-anilinofluorane, 3 (N-isoamyl-N-ethylamino) -6-methyl-7-anilinofluorane, 3- (Nn-hexyl-N-ethylamino) -6-methyl-7-anilinofluorane, 3- [N- (3-Ethoxypropyl) -N-ethylamino) -6-methyl-7-anilinofluorane, 3- [N- (3-ethoxypropyl) -N-methylamino) -6-methyl-7 -Anilinofluorane, 3-diethylamino-7- (2-chloroanilino) fluorane, 3-di (n-butyl) amino-7- (2-chloroanilino) fluorane, 3-diethylamino-6-methyl-7-anilino Fluorane, 3-diethylamino-6-methyl-7- (2,6-dimethylanilino) fluorane, 3-diethylamino-6-methyl-7- (2,4-dimethylanilino) fluor 2,4-dimethyl-6- (4-dimethylaminoanilino) fluorane, and 3- (N-cyclohexyl-N-methylamino) -6-methyl-7-anilinofluorane. .

  Among the dye precursors that develop a black color tone, 3-di (n-butyl) amino-6-methyl-7-anilinofluorane and 3-di (n-amyl) are relatively excellent in light resistance. Amino-6-methyl-7-anilinofluorane, 3-diethylamino-6-methyl-7- (2,6-dimethylanilino) fluorane, 3-diethylamino-6-methyl-7- (2,4-dimethyl) It is preferable to use at least one selected from anilino) fluorane and 2,4-dimethyl-6- (4-dimethylaminoanilino) fluorane.

  Examples of the dye precursor that develops a blue color tone include 3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide, 3- (4-diethylamino-2-methylphenyl) -3- (4 -Dimethylaminophenyl) -6-dimethylaminophthalide, 3- (4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2-methylindol-3-yl) -4-azaphthalide, 3- ( 1-ethyl-2-methylindol-3-yl) -3- (4-diethylaminophenyl) phthalide, 3- (1-ethyl-2-methylindol-3-yl) -3- (2-methyl-4-) Diethylaminophenyl) -4-azaphthalide, 3- (1-ethyl-2-methylindol-3-yl) -3- (2-ethoxy-4-diethylaminophenyl) -4- Zaphthalide, 3- (1-ethyl-2-methylindol-3-yl) -3- (2-n-hexyloxy-4-diethylaminophenyl) -4-azaphthalide, and 3-diphenylamino-6-diphenylaminofur Oran etc. can be mentioned.

  Examples of the dye precursor that develops a cyan color tone include 3- (1-ethyl-2-methylindol-3-yl) -3- (4-diethylamino-2-methylphenyl) -4-azaphthalide, 3- [1,1-bis (p-diethylaminophenyl) ethylene-2-yl] -6-dimethylaminophthalide, 3,3-bis (4-diethylamino-2-ethoxyphenyl) -4-azaphthalide, and the like. it can.

  Examples of the dye precursor that develops a green color tone include 3- (N-ethyl-Nn-hexylamino) -7-anilinofluorane, 3-diethylamino-7-dibenzylaminofluorane, 3, 3 -Bis (4-diethylamino-2-ethoxyphenyl) -4-azaphthalide, 3- (N-ethyl-Np-tolylamino) -7- (N-phenyl-N-methylamino) fluorane, 3- [p- (P-anilinoanilino) anilino] -6-methyl-7-chlorofluorane, 3,6-bis (dimethylamino) fluorene-9-spiro-3 '-(6'-dimethylamino) phthalide and the like. it can.

  The dye precursor having absorption in the near infrared region is 3,3-bis [1,1-bis (4-pyrrolidinophenyl) ethylene-2-yl] -4,5,6,7-tetra. Bromophthalide, 3,3-bis [1- (4-methoxyphenyl) -1- (4-dimethylaminophenyl) ethylene-2-yl] -4,5,6,7-tetrachlorophthalide, 3, 3-bis [1- (4-methoxyphenyl) -1- (4-pyrrolidinophenyl) ethylene-2-yl] -4,5,6,7-tetrachlorophthalide, 3- [p- (p- Anilinoanilino) anilino] -6-methyl-7-chlorofluorane, 3- [p- (p-dimethylaminoanilino) anilino] -6-methyl-7-chlorofluorane, 3,6-bis (dimethylamino) Fluorene-9-spiro-3 '-(6' Dimethylamino) phthalide, bis (p-dimethylaminostyryl) -p-tolylsulfonylmethane, 3- [p- (p-dimethylaminoanilino) anilino] -6-methylfluorane, 3-di (n-pentyl) Amino-6,8,8-trimethyl-8,9-dihydro- (3,2, e) pyridfluorane, 3-di (n-butyl) amino-6,8,8-trimethyl-8,9-dihydro- ( 3,2, e) pyridofluorane, 3- (pn-butylaminoanilino) -6-methyl-7-chlorofluorane, 2-mesidino-8-diethylamino-benz [C] fluorane .

  Examples of the dye precursor that develops a red color tone include 3,6-bis (diethylamino) fluorane-γ-anilinolactam, 3,6-bis (diethylamino) fluorane-γ- (p-nitro) anilinolactam, 3,6-bis (diethylamino) fluorane-γ- (o-chloro) anilinolactam, 3-dimethylamino-7-bromofluorane, 3-diethylaminofluorane, 3-diethylamino-6-methylfluorane, 3- Diethylamino-7-methylfluorane, 3-diethylamino-7-chlorofluorane, 3-diethylamino-7-bromofluorane, 3-diethylamino-7,8-benzofluorane, 3-diethylamino-6,8-dimethylfluorane Oran, 3-diethylamino-6-methyl-7-chlorofluorane, 3-diethylamino 7-tert-butylfluorane, 3- (N-ethyl-N-tolylamino) -7-methylfluorane, 3- (N-ethyl-N-tolylamino) -7-ethylfluorane, and 3- (N- And ethyl-N-isobutylamino) -6-methyl-7-chlorofluorane.

  Furthermore, as a dye precursor that develops a red color tone, 3-cyclohexylamino-6-chlorofluorane, 3-di (n-butyl) amino-6-methyl-7-bromofluorane, 3-di (n -Butyl) amino-7,8-benzofluorane, 3-tolylamino-7-methylfluorane, 3-tolylamino-7-ethylfluorane, 2- (N-acetylanilino) -3-methyl-6-di (N-butyl) aminofluorane, 2- (N-propionylanilino) -3-methyl-6-di (n-butyl) aminofluorane, 2- (N-benzoylanilino) -3-methyl-6 -Di (n-butyl) aminofluorane, 2- (N-carbobutoxyanilino) -3-methyl-6-di (n-butyl) aminofluorane, 2- (N-formylanilino) -3-methyl- 6 Di (n-butyl) aminofluorane, 2- (N-benzylanilino) -3-methyl-6-di (n-butyl) aminofluorane, 2- (N-allylanilino) -3-methyl-6 Examples include di (n-butyl) aminofluorane, 2- (N-methylanilino) -3-methyl-6-di (n-butyl) aminofluorane, 3-diethylamino-7-phenoxyfluorane, and the like. .

  Furthermore, 3,3-bis (1-ethyl-2-methylindol-3-yl) phthalide, 3,3-bis (1-n-octyl-2-methylindol-3-yl) phthalide, 7- ( N-ethyl-N-isoamylamino) -3-methyl-1-phenylspiro [(1,4-dihydrochromeno [2,3-c] pyrazole) -4,3′-phthalide], 7- (N— Ethyl-N-isoamylamino) -3-methyl-1-p-methylphenylspiro [(1,4-dihydrochromeno [2,3-c] pyrazole) -4,3′-phthalide], and 7- ( N-ethyl-Nn-hexylamino) -3-methyl-1-phenylspiro [(1,4-dihydrochromeno [2,3-c] pyrazole) -4,3′-phthalide] etc. in magenta color Listed as a dye precursor that develops colors It is possible.

  Examples of dye precursors that develop a magenta color tone include 3- (N-ethyl-N-isoamylamino) -7,8-benzofluorane, 3,3-bis (1-n-butyl-2-methyl). Indol-3-yl) phthalide, 3- (N-ethyl-N-isoamylamino) -7-phenoxyfluorane and the like can also be mentioned.

  Examples of the dye precursor that develops a yellow color tone include 3,6-dimethoxyfluorane and 1- (4-n-dodecyloxy-3-methoxyphenyl) -2- (2-quinolyl) ethylene. .

  The anti-counterfeit portion in the present invention contains a specific dye precursor and a developer, and the form and other component materials that can be included are appropriately selected from those that can be used for the heat-sensitive recording layer. be able to.

  In the present invention, the form of the dye precursor contained in the heat-sensitive recording layer is not particularly limited, and may be contained in the heat-sensitive recording layer in the form of solid dispersed fine particles. May be contained in the heat-sensitive recording layer in a form in which composite fine particles containing a polymer compound such as a photosensitive resin are formed.

  When the dye precursor is used in the form of solid dispersed fine particles, for example, water is used as a dispersion medium and pulverized by various wet pulverizers such as a sand mill, an attritor, a ball mill, and a cobo mill to obtain a dispersion. In addition to water-soluble polymer compounds such as polyacrylamide, polyvinylpyrrolidone, polyvinyl alcohol, modified polyvinyl alcohols such as sulfone-modified polyvinyl alcohol, methylcellulose, carboxymethylcellulose, styrene-maleic anhydride copolymer salts and derivatives thereof, are necessary. Depending on the above, it can be dispersed in a dispersion medium in the presence of a surfactant, an antifoaming agent or the like to form a dispersion. What is necessary is just to prepare the coating liquid for forming a thermosensitive recording layer using this dispersion liquid. In addition, after dissolving the dye precursor in an organic solvent, this solution is emulsified and dispersed in water using the above water-soluble polymer compound as a stabilizer, and then the organic solvent is evaporated from the emulsion to make the dye precursor into solid dispersed fine particles. Can also be used. In any case, the volume average particle diameter of the solid dispersion fine particles of the dye precursor used in the form of the solid dispersion fine particles is preferably about 0.2 to 3.0 μm, more preferably in order to obtain appropriate recording sensitivity. Is about 0.3 to 1.0 μm.

As a form in which composite fine particles containing a dye precursor and a hydrophobic resin are formed,
(1) A form in which one or more dye precursors are microencapsulated using a hydrophobic resin as a wall film,
(2) A form in which one or more dye precursors are contained in a base material made of a hydrophobic resin obtained from a polyvalent isocyanate or the like,
(3) A form in which a compound having an unsaturated carbon bond is polymerized on the surface of one or more dye precursor fine particles,
Etc. For example, a method described in JP-A-60-244594 can be cited as a method for producing the particles having the form (1). Examples of the method for producing particles having the form (2) include the method described in JP-A-9-263057. Examples of the method for producing the particles having the form (3) include the method described in JP-A No. 2000-158822.

  The hydrophobic resin forming the composite fine particles is not particularly limited, and examples thereof include urea resins, urethane resins, urea-urethane resins, styrene resins, acrylic resins, and the like. Among these, since the urea-based resin and the urea-urethane resin are excellent in heat-resistant surface fogging property, a form in which the second dye precursor forms composite fine particles with the polyurea or polyurea-polyurethane resin is preferable.

  The polyvalent isocyanate compound used for the production of the composite fine particles is a compound that forms polyurea or polyurea-polyurethane by reacting with water, and may be a polyvalent isocyanate compound alone or a polyvalent isocyanate. It may be a compound, a polyol that reacts with this, a mixture of polyamines, or an adduct of a polyvalent isocyanate compound and a polyol, a multimer such as a biuret or isocyanurate of a polyvalent isocyanate compound. A dye precursor is dissolved in these polyvalent isocyanate compounds, and this solution is dissolved in an aqueous medium containing a protective colloid substance such as polyvinyl alcohol, and the volume average particle diameter is preferably 0.2 to 3.0 μm. The polyisocyanate compound is obtained by emulsifying and dispersing to a degree, more preferably about 0.2 to 1.5 μm, and further, if necessary, mixing a reactive substance such as polyamine and then heating the emulsified dispersion. Polymerize. As a result, the polyvalent isocyanate compound can be polymerized to form composite fine particles containing the dye precursor.

  The dye precursor contained in the composite fine particles is highly separable from the outside, and the color former is very good storage stability, especially oils and plasticizers, compared to the color former colored in the state of solid dispersed fine particles. It is excellent in resistance to. The reason for this is not necessarily clear, but it is considered that the color former and the polymer substance (matrix) have some interaction and are stabilized.

  The appearance of the composite fine particles used in the present invention is almost spherical when observed with an electron microscope, or is somewhat erythrocytic. In cross-sectional observation with an electron microscope, the shape is an internal body, a porous body, or a hollow body. The average particle size is desirably about 0.2 to 1.5 μm in order to obtain appropriate recording sensitivity. By setting the average particle diameter to 0.2 μm or more, it is desirable from the viewpoint of improving the storage stability of the color developing part with respect to oil, plasticizer and the like.

  The composite fine particles used in the present invention include, in addition to the dye precursor, a UV absorber, an antioxidant, a release agent, which will be described later, and a sensitizer known as a heat-sensitive recording material, if necessary. May be added.

  The content ratio of the dye precursor is preferably about 5 to 30% by mass, more preferably about 7 to 30% by mass, and still more preferably about 7 to 25% by mass in the total solid content of each thermosensitive recording layer. By setting the content to 5% by mass or more, the color density can be improved. Heat resistance can be improved by setting it as 30 mass% or less.

  The developer that can be used in the heat-sensitive recording layer in the present invention is selected from those having the property of being liquefied or dissolved by increasing the temperature, and having the property of developing the color by contact with the dye precursor. Examples thereof include organic acidic substances such as phenol compounds, aromatic carboxylic acids, and polyvalent metal salts of these compounds.

  The developer usually exists in the form of composite fine particles, microcapsules, and solid dispersed fine particles. The content of the developer is preferably about 30 to 1500 parts by weight, more preferably about 50 to 1000 parts by weight, and still more preferably 100 to 600 parts per 100 parts by weight of the total dye precursor in each thermosensitive recording layer. About 200 parts by mass, particularly preferably about 140 to 600 parts by mass, and most preferably about 200 to 500 parts by mass. The composite fine particles can be prepared by a method similar to the method of preparing the composite fine particles containing the dye precursor.

  As typical developers, for example, 4-tert-butylphenol, 4-acetylphenol, 4-tert-octylphenol, 4,4′-sec-butylidene diphenol, 4-phenylphenol, 4,4′-dihydroxy Diphenylmethane, 4,4′-isopropylidene diphenol, 4,4′-dihydroxydiphenyl ether, 4,4′-cyclohexylidene diphenol, 1,1-bis (4-hydroxyphenyl) ethane, 1,1-bis (4 -Hydroxyphenyl) -1-phenylethane, 4,4'-dihydroxydiphenyl sulfide, 4,4'-thiobis (3-methyl-6-tert-butylphenol), 4,4'-dihydroxydiphenylsulfone, 2,4 ' -Dihydroxydiphenylsulfone, 4-hydroxy -4'-isopropoxydiphenylsulfone, 4-hydroxy-4'-n-propoxydiphenylsulfone, 4-hydroxy-4'-allyloxydiphenylsulfone, bis (3-allyl-4-hydroxyphenyl) sulfone, 4,4 '-Bis [(4-methyl-3-phenoxycarbonylaminophenyl) ureido] diphenylsulfone, 4- [4'-(1'-methylethyloxy) phenyl] sulfonylphenol, N- (p-toluenesulfonyl) -N '-(3-p-toluenesulfonyloxyphenyl) urea, Np-tolylsulfonyl-p-butoxycarbonylphenylurea, N- (p-toluenesulfonyl) -N'-phenylurea, 4,4'-bis ( And compounds such as 3-tosylureido) diphenylmethane .

  Further, in the present invention, compounds that can be used as a developer include 4-hydroxybenzophenone, dimethyl 4-hydroxyphthalate, methyl 4-hydroxybenzoate, propyl 4-hydroxybenzoate, and 4-hydroxybenzoic acid-sec-butyl. Phenyl compounds such as phenyl 4-hydroxybenzoate, benzyl 4-hydroxybenzoate, tolyl 4-hydroxybenzoate, chlorophenyl 4-hydroxybenzoate, 4,4′-dihydroxydiphenyl ether, or benzoic acid, p-tert- Butylbenzoic acid, trichlorobenzoic acid, terephthalic acid, salicylic acid, 3-tert-butylsalicylic acid, 3-isopropylsalicylic acid, 3-benzylsalicylic acid, 3,5- (α-methylbenzyl) salicylic acid, 3,5-di-tert- Butyl Sari Aromatic carboxylic acids such as Le acid, and the phenolic compounds, aromatic carboxylic acid and, for example, zinc, magnesium, aluminum, organic acidic substances of salts with polyvalent metals such as calcium and the like.

  Among these, 4-hydroxy-4′-isopropoxydiphenyl sulfone, 4-hydroxy-4′-n-propoxydiphenyl are used as color developers that react with a dye precursor having a pyridine skeleton under heating to develop color. Sulfone, Np-tolylsulfonyl-p-butoxycarbonylphenylurea, N- (p-toluenesulfonyl) -N ′-(3-p-toluenesulfonyloxyphenyl) urea, N- (p-toluenesulfonyl) -N At least one selected from '-phenylurea, 4,4'-bis [(4-methyl-3-phenoxycarbonylaminophenyl) ureido] diphenylsulfone, and 4,4'-bis (3-tosylureido) diphenylmethane is preferable. As a result, the color density is increased, a brighter color image is obtained in the visible light region, and the fluorescence under ultraviolet light is excellent.

  In the present invention, the thermosensitive coloring portion includes the first dye precursor and the second dye precursor as the dye precursor, the first dye precursor is contained in the form of solid dispersed fine particles, and has a color tone different from that of the first dye precursor. The second dye precursor that develops color is contained in the form of composite fine particles containing the second dye precursor and the polymer compound, and either one of the first dye precursor and the second dye precursor has the pyridine skeleton. A dye precursor is preferred. The dye precursor contained in the composite fine particles is highly separable from the outside. For example, the first dye precursor is colored at a low temperature and the second dye precursor is colored at a high temperature, and the color precursor is excellent. Multicolor thermal recording is possible. As a specific example, for example, when a dye precursor having a pyridine skeleton is used as the first dye precursor and a dye precursor that develops a black color tone is used as the second dye precursor, the authenticity determination is performed. Information is recorded as a color image of a yellow color tone by the first dye precursor, and at least one of general fixed information and variable information is colored by both the first dye precursor and the second dye precursor and mixed. Thus, multicolor thermal recording can be performed as a black-colored color image. The use of a dye precursor having a pyridine skeleton as the first dye precursor is preferred because there is no risk of impairing the fluorescence due to color mixing at high temperatures, and the effects of the present invention can be exhibited without regret.

  In another embodiment of the present invention, the thermosensitive coloring portion has a multilayer structure comprising at least a first thermosensitive recording layer and a second thermosensitive recording layer, and the first thermosensitive recording layer is in the form of solid dispersed fine particles. A second thermosensitive recording layer containing a second dye precursor in the form of a composite fine particle comprising a second dye precursor and a polymer compound, the first dye precursor and the second dye precursor Either one is preferably a dye precursor having the pyridine skeleton. By using a multilayer structure, the color separation can be further enhanced. Either the first thermosensitive recording layer or the second thermosensitive recording layer may be on the side close to the support.

  As a method for performing multicolor thermal recording in the present invention, for example, a thermal head can be used and recording can be performed by changing the applied energy by controlling the width of one pulse and the number of repetitions with a constant applied voltage. As a specific example, for example, it is sufficient to reach the color development start temperature of the solid dispersion fine particles of the first dye precursor, and is insufficient to reach the color development start temperature of the composite fine particles containing the second dye precursor. By applying a certain applied energy, a color tone by color development of the first dye precursor can be obtained. On the other hand, the first dye precursor and the second dye precursor are given by applying sufficient energy to reach the color development start temperature of both the solid dispersed fine particles of the first dye precursor and the composite fine particles containing the second dye precursor. A second color is obtained by color-mixing both bodies.

  Since the color development start temperature also depends on the polymer characteristics of the composite fine particles and the type of the developer, it is not limited by the type of the dye precursor having a specific melting point. These dye precursors can be selected and used in combination. The polymer characteristics of the composite fine particles can be controlled by the composition and production conditions of the composite fine particles such as the polyvalent isocyanate compound and reaction accelerator used.

  According to another aspect of the present invention, (1) a support, and (2) a first dye precursor and a developer that reacts with the first dye precursor under heating to develop a color from the side close to the support. A first heat-sensitive recording layer containing a colorant; (3) an intermediate layer; (4) a particle component containing a second dye precursor; and a developed color that reacts with the second dye precursor under heating to cause color development. A second heat-sensitive recording layer containing an agent; and (5) a third heat-sensitive agent containing a particle component containing a third dye precursor and a color developer that reacts with the third dye precursor under heating to develop color. The recording layer has a first dye precursor, a second dye precursor, and a third dye precursor, each of which is a dye precursor capable of developing a different color tone, and is included in the second thermosensitive recording layer. The fine particle component containing the second dye precursor comprises a second dye precursor and a polymer compound. The particle component containing the third dye precursor contained in the third heat-sensitive recording layer contains composite fine particles containing the third dye precursor and the polymer compound, and the first, second and third By making a multicolor thermosensitive recording material in which any one of the dye precursors is a dye precursor having the pyridine skeleton, multicolor thermosensitive recording of at least four kinds of color tones including color mixing due to color development of all the dye precursors Is possible. Here, the color developer is selected or selected so that the color development start temperature of the second thermosensitive recording layer is higher than the color development start temperature of the first thermosensitive recording layer and lower than the color development start temperature of the third thermosensitive recording layer. (2) The composite fine particles in the thermosensitive recording layer are prepared, and the color developer is selected or the color developing start temperature of the third thermosensitive recording layer is higher than the color developing start temperatures of the first thermosensitive recording layer and the second thermosensitive recording layer. The composite fine particles in the third thermosensitive recording layer may be prepared. From the viewpoint of improving the fluorescence, it is likely that any one of the first and third dye precursors is a dye precursor having the pyridine skeleton because the second dye precursor may impair the fluorescence due to color mixing. preferable.

  In the present invention, a preservability improving agent can be further contained in the heat-sensitive recording layer mainly in order to further improve the preservability of the color image. Examples of such preservability improvers include 1,1,3-tris (2-methyl-4-hydroxy-5-cyclohexylphenyl) butane, 1,1,3-tris (2-methyl-4-hydroxy-). 5-tert-butylphenyl) butane, 1,1-bis (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 4,4 ′-[1,4-phenylenebis (1-methylethylidene) ] Phenols such as bisphenol and 4,4 '-[1,3-phenylenebis (1-methylethylidene)] bisphenol, 4-benzyloxyphenyl-4'-(2-methyl-2,3-epoxypropyloxy) ) Phenylsulfone, 4- (2-methyl-1,2-epoxyethyl) diphenylsulfone, and 4- (2-ethyl-1,2-epoxyethyl) ) At least one selected from epoxy compounds such as diphenylsulfone and isocyanuric acid compounds such as 1,3,5-tris (2,6-dimethylbenzyl-3-hydroxy-4-tert-butyl) isocyanuric acid is used. be able to. Of course, the storage stability improving agent is not limited to these, and two or more kinds of compounds may be used in combination as required.

  In the present invention, a sensitizer can be further contained in the heat-sensitive recording layer in order to improve the recording sensitivity. As the sensitizer, a compound conventionally known as a sensitizer for a thermal recording material can be used. For example, parabenzylbiphenyl, dibenzyl terephthalate, phenyl 1-hydroxy-2-naphthoate, dioxalate Benzyl ester, di-o-chlorobenzyl adipate, 1,2-diphenoxyethane, 1,2-di (3-methylphenoxy) ethane, di-p-methylbenzyl oxalate, di-p-chlorooxalate Benzyl ester, 2-naphthylbenzyl ether, diphenylsulfone, 1,2-diphenoxymethylbenzene, 1,2-bis (3,4-dimethylphenyl) ethane, 1,3-bis (2-naphthoxy) propane, metater Phenyl, diphenyl, benzophenone and the like can be mentioned.

  Auxiliaries such as developers, storability improvers and sensitizers used in the heat-sensitive recording layer are dispersed in water in the same manner as when the dye precursor is used in the form of solid dispersed fine particles. What is necessary is just to mix with this in the case of preparation of a coating liquid. Moreover, these adjuvants can be dissolved in a solvent and emulsified in water using a water-soluble polymer compound as an emulsifier. Further, the preservability improver and the sensitizer may be contained in the composite fine particles containing the dye precursor.

  In order to improve the whiteness of the heat-sensitive recording layer and improve the uniformity of the image, a fine pigment having a high whiteness and an average particle diameter of 10 μm or less can be contained in the heat-sensitive recording layer. For example, calcium carbonate, magnesium carbonate, kaolin, clay, talc, calcined clay, silica, diatomaceous earth, synthetic aluminum silicate, zinc oxide, titanium oxide, aluminum hydroxide, barium sulfate, surface treated inorganic pigments such as calcium carbonate and silica In addition, organic pigments such as urea-formalin resin, styrene-methacrylic acid copolymer resin, and polystyrene resin can be used.

  As other component materials constituting the heat-sensitive recording layer, a binder is used, and if necessary, a crosslinking agent, waxes, metal soaps, colored dyes, colored pigments, fluorescent dyes and the like can be used. Examples of the binder include polyvinyl alcohol and derivatives thereof, starch and derivatives thereof, cellulose derivatives such as hydroxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, methylcellulose, and ethylcellulose, polyacrylic acid soda, polyvinylpyrrolidone, and acrylamide-acrylic acid ester copolymer. Water-soluble polymer materials such as acrylamide-acrylic acid ester-methacrylic acid ester copolymer, styrene-maleic anhydride copolymer, isobutylene-maleic anhydride copolymer, casein, gelatin and derivatives thereof, and Polyvinyl acetate, polyurethane, polyacrylic acid, polyacrylic ester, vinyl chloride-vinyl acetate copolymer, polybutyl methacrylate, ethylene-vinyl acetate Butadiene copolymer, styrene - - emulsion and styrene polymers such as butadiene - can be given latex water-insoluble polymer such as an acrylic copolymer.

  The anti-counterfeiting part of the present invention has a tendency that the color image is fading under a high temperature and high humidity environment such as 40 ° C. and 90% RH. It has a fogging property, and can emit fluorescence due to background fogging at a high temperature of preferably 40 ° C. or higher, more preferably 50 ° C. or higher, and still more preferably 60 ° C. or higher. Further, the anti-counterfeiting part tends to fade with an organic solvent such as acetone, but can emit fluorescence due to background fog when the solvent volatilizes. For this reason, for example, unlike a reversible thermosensitive recording medium that is initialized at a high temperature and can be rewritten, even if it is exposed to a high temperature or a solvent as an attempt to falsify variable information, for example, the anti-counterfeiting part causes background fogging and is read. It is possible to make it impossible, or to issue a warning when the anti-counterfeiting unit provided as a latent image causes background fogging and visualizes it. The anti-counterfeiting part that causes the background fog does not return to the initial state in which the specific dye precursor and the developer are dispersed and separated from each other, so that the anti-counterfeiting effect with a fluorescent reaction is excellent. It can be demonstrated.

  In this invention, it is preferable that the forgery prevention part contains an ethylene-acrylic copolymer, or is equipped with the coating part which contains an ethylene-acrylic copolymer and adjoins the forgery prevention part. Thereby, an ethylene-acrylic copolymer can effectively produce the background fog of a forgery prevention part, and can improve forgery prevention property. Examples of the ethylene-acrylic copolymer are commercially available as Hi-Tech S-3121 (manufactured by Toho Chemical Co., Ltd.) and Syxen NC (manufactured by Sumitomo Seika Co., Ltd.), and can be easily obtained and used. The ratio of the ethylene component in the ethylene-acrylic copolymer is preferably about 50 to 90 mol%. The covering portion is made of, for example, a heat-sensitive recording layer different from the forgery prevention portion, an undercoat layer, an intermediate layer, a protective layer, or a resin layer described later. These layers may be layers formed in a pattern. The covering part is preferably formed on the side close to the support of the forgery prevention part or the side far from the support so as to overlap the forgery prevention part.

  A crosslinking agent for curing the binder can be contained in the heat-sensitive recording layer. Thereby, the water resistance of the thermosensitive recording layer can be improved. Specific examples of the crosslinking agent include, for example, aldehyde compounds such as glyoxal, polyamine compounds such as polyethyleneimine, epoxy compounds, polyamide resins, melamine resins, glyoxylate, dimethylol urea compounds, aziridine compounds, and block isocyanate compounds. And at least one crosslinking agent selected from inorganic compounds such as ammonium persulfate, ferric chloride, magnesium chloride, sodium tetraborate, potassium tetraborate, boric acid, boric acid triester, boron-based polymers, hydrazide compounds, and the like. It is preferably used in the range of about 1 to 10 parts by mass with respect to 100 parts by mass of the total solid content of the thermosensitive recording layer.

  Examples of the wax added to the heat-sensitive recording layer include waxes such as paraffin wax, carnauba wax, microcrystalline wax, polyolefin wax, and polyethylene wax, and higher fatty acid amides such as stearamide, ethylenebisstearic amide, and higher. Examples thereof include fatty acid esters and derivatives thereof.

  Examples of the metal soap added to the heat-sensitive recording layer include higher fatty acid polyvalent metal salts such as zinc stearate, aluminum stearate, calcium stearate, and zinc oleate. When the anti-counterfeit recording material of the present invention is a two-color heat-sensitive recording material, it is possible to add a colored dye or colored pigment having a color tone complementary to the low-temperature color tone to the color recording image. It is preferably used for adjusting the color tone of the multicolor thermal recording material before and after printing (printing). Further, if necessary, various auxiliary agents such as an oil repellent, an antifoaming agent and a viscosity modifier can be further added to the heat-sensitive recording layer as long as the effects of the present invention are not impaired.

  Further, in the heat-sensitive recording layer, microcapsules encapsulating the ultraviolet absorber or solid dispersed fine particles of the ultraviolet absorber can be added to greatly improve the light resistance.

  Specific examples of the ultraviolet absorber include salicylic acid-based ultraviolet absorbers such as phenyl salicylate, p-tert-butylphenyl salicylate, p-octylphenyl salicylate, 2,4-dihydroxybenzophenone, 2-hydroxy-4-octyloxy Benzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2,2′-dihydroxy-4-methoxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, 2- Examples thereof include benzophenone-based ultraviolet absorbers such as hydroxy-4-methoxy-5sulfobenzophenone.

  Furthermore, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-5′-tert-butylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-tert-butylphenyl) benzotriazole, 2- (2′-hydroxy-3′-tert-butyl-5′-methylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-3) ', 5'-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3', 5'-di-tert-amylphenyl) benzotriazole, 2- [2'-hydroxy -3 ′-(3 ″, 4 ″, 5 ″, 6 ″ -tetrahydrophthalimido-methyl) -5′-methylphenyl] benzotriazole, 2- (2 ′ Hydroxy-5′-tert-octylphenyl) benzotriazole, 2- [2′-hydroxy-3 ′, 5′-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2- (2′- Hydroxy-3'-dodecyl-5'-methylphenyl) benzotriazole, 2- [2'-hydroxy-4 '-(2 "-ethylhexyl) oxyphenyl] benzotriazole, polyethylene glycol (molecular weight about 300) and methyl-3 -[3-tert-butyl-5- (2H-benzotriazol-2-yl) -4-hydroxyphenyl] benzoic acid UV absorbers such as condensates with propionate, 2'-ethylhexyl-2-cyano- 3,3-diphenyl acrylate, ethyl-2-cyano-3,3-diphenyl acrylate It may be mentioned ultraviolet absorbent cyanoacrylate such bets, and the like. Of course, not limited thereto, may be used in combination of two or more depending also required.

  Among these ultraviolet absorbers, benzotriazole-based ultraviolet absorbers are preferable, and in particular, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole and 2- (2′-hydroxy-3′-tert-butyl-5). -Methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3'-dodecyl-5'-methylphenyl) benzotriazole, 2- [2'-hydroxy-4 '-(2 "-ethylhexyl) A condensate of oxyphenyl] benzotriazole, polyethylene glycol (molecular weight about 300) and methyl-3- [3-tert-butyl-5- (2H-benzotriazol-2-yl) -4-hydroxyphenyl] propionate is In particular, it is more preferable because it exhibits a remarkable light resistance improvement effect.

  The content ratio of the microcapsules encapsulating the ultraviolet absorber or the solid dispersed fine particles of the ultraviolet absorber is not particularly limited, but is preferably about 5 to 70% by mass in the total solid content of the heat-sensitive recording layer. Especially preferably, it adjusts to the range of about 15-50 mass%. Light resistance can be improved by setting it as 5 mass% or more. If it exceeds 70% by mass, the light resistance is saturated, so that it is preferably about 70% by mass or less from the viewpoint of improving the recording sensitivity. The light resistance can be improved more effectively when the microcapsules encapsulating the ultraviolet absorber or the solid dispersed fine particles of the ultraviolet absorber are contained in the protective layer, which will be described later, rather than in the heat-sensitive recording layer. .

  The microcapsules encapsulating the ultraviolet absorber can be prepared by various known methods. In general, the core substance obtained by dissolving the above-described solid or liquid ultraviolet absorber in an organic solvent as required at room temperature ( Oily liquid) is prepared by a method of emulsifying and dispersing an oily liquid in an aqueous medium to form a wall film made of a polymer substance around oily droplets. Specific examples of the polymer substance that becomes the wall film of the microcapsule include, for example, polyurethane resin, polyurea resin, polyamide resin, polyester resin, polycarbonate resin, aminoaldehyde resin, melamine resin, polystyrene resin, styrene-methacrylate copolymer resin, Examples thereof include styrene-acrylate resin, gelatin, polyvinyl alcohol and the like.

The anti-counterfeit part or the heat-sensitive recording layer in the present invention is a dispersion in which, for example, water is used as a dispersion medium, and a specific dye precursor, a developer, a sensitizer, a shelf life improver, etc. are dispersed together or separately. The coating amount prepared by mixing and stirring pigments, binders, crosslinking agents, other auxiliaries and the like, if necessary, is preferably about ² to 12 g / m ^{2 in} dry weight, more preferably 2 to 8 g / ^{m 2} approximately, are formed further preferably such that the 2~7g / ^{m 2} approximately, coating and drying on a support.

  The support in the present invention is not particularly limited in type, shape, dimensions, etc., for example, high-quality paper (acidic paper, neutral paper), medium-quality paper, coated paper, art paper, cast-coated paper, glassine paper, resin In addition to laminated paper, polyolefin synthetic paper, synthetic fiber paper, non-woven fabric, synthetic resin film, and the like, various transparent supports can be appropriately selected and used. When using the present invention for a magnetic ticket application, it is desirable to use paper, but when using the present invention for a prepaid card, IC card, or magnetic commuter pass application, a polyethylene terephthalate having a thickness of 100 μm or more is used. It is desirable from the viewpoint of recording sensitivity to use a plastic substrate, particularly a foamed substrate. Of course, a laminate substrate of a foamed polyethylene terephthalate film and a non-foamed polyethylene terephthalate film can also be used.

In the present invention, if necessary, an undercoat layer can be provided, for example, between the support and the heat-sensitive recording layer. Thereby, the recording sensitivity can be further increased. The undercoat layer supports an undercoat layer coating liquid containing an oil-absorbing pigment having an oil absorption of 70 ml / 100 g or more, particularly about 80 to 150 ml / 100 g, at least one of organic hollow particles and thermally expandable particles, and a binder. It is formed by applying and drying on top. Here, the oil absorption is a value determined according to the method described in JIS K 5101. By using a pigment having a high porosity such as silica or calcined kaolin for the undercoat layer, the recording sensitivity of the thermosensitive recording layer can be increased. Further, the inclusion of a plastic pigment, hollow particles, foam, etc. in the undercoat layer is effective in improving the recording sensitivity of the thermosensitive recording layer formed thereon. The coating amount of the undercoat layer coating solution is preferably about 3 to ²⁰ g / m ² by dry weight, and more preferably about 4 to 12 g / m ² .

  The binder in the undercoat layer can be appropriately selected from those that can be used for the heat-sensitive recording layer. Among these recording sensitivities, starch-vinyl acetate graft copolymer, polyvinyl alcohol, styrene-butadiene latex and the like are preferable from the viewpoint of improving barrier properties.

  In the present invention, for example, when a plurality of heat-sensitive recording layers are provided, an intermediate layer may be provided between them or between the heat-sensitive recording layer and the protective layer. For the intermediate layer, a water-soluble polymer material or a water-insoluble polymer used in conventionally known thermal recording materials can be used. Specific examples include those similar to the specific examples used as the recording sensitivity mentioned in the heat-sensitive recording layer. Further, the intermediate layer may contain an organic compound such as a pigment having a high porosity such as silica or calcined kaolin, a plastic pigment, a hollow particle, a foam, or a polyethylene wax having a glass transition point or a melting point as an auxiliary agent.

The intermediate layer is generally coated with an intermediate layer coating solution prepared by mixing water as a dispersion medium, for example, a water-soluble polymer material and, if necessary, various additives such as an auxiliary agent and a surfactant. Is preferably applied and dried so that the dry weight is preferably about 3.0 to 40.0 g / m ² , more preferably about 8.0 to 35.0 g / m ² .

  In the present invention, for example, it is desirable to provide a protective layer containing a water-soluble polymer material and a pigment as used in a conventionally known thermal recording material on the thermal recording layer. As the water-soluble polymer material and the pigment, materials exemplified in the above-mentioned heat-sensitive recording layer can be used. At this time, it is more desirable to add a crosslinking agent to impart water resistance to the protective layer.

  In the present invention, the light resistance can be greatly improved by containing microcapsules encapsulating the ultraviolet absorber or solid dispersed fine particles of the ultraviolet absorber in the protective layer. In particular, microcapsules having a wall film made of polyurethane-polyurea resin or aminoaldehyde resin are excellent in heat resistance, and are therefore added to the thermal recording layer or protective layer for the purpose of preventing sticking to the thermal head. In addition to the excellent accompanying effect of fulfilling the function of an inorganic pigment, the refractive index is lower than that of other wall membrane microcapsules and ordinary pigments, and the shape is spherical. Even if it is added in a large amount, it is preferably used because it does not cause a decrease in density due to irregular reflection of light.

  Furthermore, by adding a pigment, it is possible to prevent sticking to the thermal head and sticking. As the oil absorption amount of the pigment, it is preferable to use a pigment of 50 ml / 100 g or more. The pigment content is preferably an amount that does not decrease the color density, that is, 50% by mass or less of the total solid content of the protective layer.

For the protective layer, for example, using a protective layer coating solution prepared by mixing and stirring recording sensitivity, a crosslinking agent, a pigment, and other auxiliaries using water as a dispersion medium, the coating amount is preferably 0 by dry weight. .1~15g / ^{m 2,} more preferably about so that 0.5 to 8 g / ^{m 2} approximately, is formed by coating and drying.

  In the present invention, a resin layer cured with an electron beam or ultraviolet light can be provided, for example, on a heat-sensitive recording layer, or on an intermediate layer or a protective layer. Examples of resins that can be cured with an electron beam are described in JP-A Nos. 58-177392 and 58-177392. In such a resin, auxiliary agents such as a non-electron beam curable resin, a pigment, an antifoaming agent, a leveling agent, a lubricant, a surfactant, and a plasticizer can be appropriately added. In particular, it is preferable to add pigments such as calcium carbonate and aluminum hydroxide, and lubricants such as waxes and silicon because this helps prevent sticking to the thermal head.

  The anti-counterfeit part in the present invention is not particularly limited as long as it is provided in at least a part of the thermosensitive coloring part.For example, between the support and the undercoat layer, between the undercoat layer and the intermediate layer, and the undercoat layer. Each of these layers, such as between a thermal recording layer different from the forgery prevention part, between a thermal recording layer and an intermediate layer different from the forgery prevention part, between an intermediate layer and a protective layer, between a protective layer and a resin layer, etc. Can be provided between or within the layers. In addition, the layers formed in a pattern may be formed so as to overlap each other, or may be formed in a portion excluding the thermosensitive recording layer different from the forgery prevention portion, for example.

  In the present invention, the anti-counterfeit recording material can be printed with UV ink, flexographic ink, or the like. Thereby, for example, fixed information can be printed, and variable information including information for authenticity determination can be recorded on the thermal recording layer. Printing may be performed on a support, or may be performed on any layer such as a heat-sensitive recording layer, an undercoat layer provided if necessary, an intermediate layer, a protective layer, or a resin layer.

  In the present invention, in order to increase the added value of the anti-counterfeit recording material, it can be further processed to provide an anti-counterfeit recording material having a higher function. In the present invention, it is preferable that at least a part of the support is provided with a thermal transfer receiving layer, an ink jet recording layer, a magnetic recording layer or an adhesive layer. These layers may be formed so that a portion where the forgery prevention portion is exposed remains, may be formed so as to overlap with the forgery prevention portion, or may be formed in a portion excluding the forgery prevention portion. For example, a pressure-sensitive adhesive paper, a re-humidified adhesive paper, or a delayed tack paper can be obtained by applying coating processing on the back surface with a pressure-sensitive adhesive, a re-humidified adhesive, a delayed tack type pressure-sensitive adhesive, or the like. In particular, the anti-counterfeit recording material of the present invention that has been subjected to adhesive processing is useful as a heat-sensitive label. Further, by using the back surface, a function as a thermal transfer paper, an ink jet paper, a carbonless paper, an electrostatic recording paper, and a xerographic paper can be added to form a recording body capable of double-sided recording. Of course, a double-sided thermal recording material can also be used. In addition, a back layer can be provided in order to suppress permeation of oil or plasticizer from the back surface of the recording material, curl control or antistatic.

  As the magnetic recording layer, a magnetic recording layer conventionally used for a magnetic ticket, a prepaid card, a magnetic commuter pass, or the like can be used. As a matter of course, the magnetic recording layer may be provided before the thermal recording layer is applied even when the magnetic recording layer is provided between the support and the thermal recording layer. It is desirable to keep the whiteness of the heat-sensitive recording layer high.

  In the present invention, the forgery prevention method for identifying an anti-counterfeit recording body is to color the anti-counterfeiting portion of the anti-counterfeit recording body under heating, and whether or not the colored image fluoresces when irradiated with ultraviolet rays. It is characterized by distinguishing between real and fake. Further, the anti-counterfeit recording material that has been subjected to falsification and exposed to high temperature or a solvent can discriminate between genuine and forgery depending on whether or not the anti-counterfeiting portion emits fluorescence by ultraviolet irradiation due to the background fogging.

  The forgery identification method in the present invention preferably includes a step of recording a color image with a thermal head. In multicolor thermal recording with a thermal head, a dye precursor having a pyridine skeleton and a dye precursor that develops a color tone different from that of the dye precursor having a pyridine skeleton can be developed separately. In this case, the thermal heads may be the same or different. For example, a dye precursor that develops a color tone different from that of a dye precursor having a pyridine skeleton at the time of ticketing can be developed as variable information, and a dye precursor having a pyridine skeleton can be developed when authenticity is determined. Moreover, both the dye precursor having a pyridine skeleton and the dye precursor that develops a color tone different from that of the dye precursor having a pyridine skeleton can be colored by one thermal scanning of the thermal head. Since the color tone of the dye precursor having a pyridine skeleton can also be used, visibility can be improved by multi-color, and it is only necessary to irradiate ultraviolet rays at the time of authenticity determination.

  Although the means for irradiating ultraviolet rays is not particularly limited, the light source may be a low pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, a chemical lamp, a black light lamp, a mercury-xenon lamp, a short arc lamp, helium.・ Cadmium laser, argon laser, sunlight.

  The method for producing a forgery-preventing recording material in the present invention includes a composition comprising a dye precursor having a pyridine skeleton and a dye precursor having a pyridine skeleton and a color developer that reacts with heating to develop color. Including a step of providing an anti-counterfeit portion by applying and drying with a coating liquid, or a step of providing an anti-counterfeit portion by forming an appropriate character or graphic latent image using an ink containing the composition. . The method for forming the latent image is not particularly limited, and examples thereof include printing or an inkjet recording method.

  Although it does not specifically limit as a coating method, It may form by apply | coating and drying one layer at a time using each coating liquid containing the coating liquid for thermosensitive recording layers for anti-counterfeit part formation, and may form two or more layers. You may perform simultaneous multilayer application | coating which apply | coats simultaneously. It can be applied at the same time as the heat-sensitive recording layer, an undercoat layer, an intermediate layer, a protective layer and the like provided as necessary. In simultaneous multi-layer coating, each coating solution is laminated and then applied, and then dried to form each layer. After applying a coating solution that forms the lower layer, the lower surface coating surface is wet without drying. In a state, you may apply | coat the coating liquid which forms an upper layer on a lower layer coating surface, and it may be made to dry after that, and may form each layer.

  Examples of methods for forming each layer on the support include air knife method, blade method, gravure method, roll coater method, spray method, dipping method, bar method, curtain method, slot die method, slide die method, and extrusion method. Any of the known coating methods may be used.

  In the present invention, smoothing can be performed using a known smoothing method such as a super calender or soft calender in an arbitrary process after the formation of each layer or after the formation of all the layers. . Thereby, image quality and recording sensitivity can be increased. The surface of the support provided with the heat-sensitive recording layer may be applied to either a calendar metal roll or an elastic roll.

  The present invention will be described in more detail with reference to examples, but the present invention is not limited thereto. Unless otherwise specified, “parts” and “%” represent “parts by mass” and “mass%”, respectively.

  The volume average particle diameters of the dye precursors, composite particles, and pigments used in Examples and Comparative Examples were measured using a laser diffraction particle size distribution analyzer SALD2200 (manufactured by Shimadzu Corporation). The diameter was measured using a dynamic light scattering particle size distribution analyzer LB-500 (manufactured by Horiba, Ltd.).

Example 1
-Preparation of liquid A (dye precursor dispersion that develops a yellow color) 4- [2- (2-octyloxyphenyl) -6-phenyl-4- as a dye precursor that develops a yellow color Pyridinyl] -N, N-dimethylbenzenamine 40 parts, polyvinyl alcohol (polymerization degree 500, saponification degree 88%) 40% 10% aqueous solution and water 20 parts were mixed, and a vertical sand mill (made by Imex Corporation, sand grinder). ) Was used to pulverize and disperse so that the volume average particle diameter was 1.3 μm to obtain a dye precursor dispersion (liquid A) that develops a yellowish color tone.

-Preparation of liquid B (developer dispersion) 40 parts of 4-hydroxy-4'-isopropoxydiphenylsulfone, 40 parts of a 10% aqueous solution of polyvinyl alcohol (polymerization degree 500, saponification degree 88%), and water 20 parts The mixture was mixed and pulverized using an ultra visco mill until the volume average particle diameter became 1.5 μm to obtain a developer dispersion (liquid B).

Preparation of liquid C (sensitizer dispersion) 40 parts of 1,2-di (3-methylphenoxy) ethane, 40 parts of 10% aqueous solution of polyvinyl alcohol (polymerization degree 500, saponification degree 88%), and water 20 parts Were mixed and pulverized and dispersed using a vertical sand mill (Sand Grinder, manufactured by IMEX Co., Ltd.) so that the volume average particle diameter was 1.0 μm, to obtain a sensitizer dispersion (liquid C).

Preparation of thermal recording layer coating liquid (1) 17 parts of liquid A, styrene-butadiene latex (trade name: L1571, manufactured by Asahi Kasei Co., Ltd., solid content concentration 48%) 8 parts, 10% aqueous polyvinyl alcohol solution (trade name: 40 parts of Poval (registered trademark) PVA-110 (manufactured by Kuraray), 34 parts of B liquid, 17 parts of C liquid, 2 parts of 5% surfactant aqueous solution (trade name: SN Wet OT-70, San Nopco), and A composition comprising 17 parts of water was mixed and stirred to obtain a thermal recording layer coating solution (1).

-Preparation of Liquid D (Kaolin Dispersion) Kaolin (trade name: UW-90 (registered trademark), manufactured by BASF) 80 parts, 40% aqueous solution of sodium polyacrylate (trade name: Aron T-50, Toagosei Co., Ltd.) 1 part) and 53 parts of water were mixed and pulverized using a sand mill until the volume average particle diameter became 1.6 μm to obtain a kaolin dispersion (liquid D).

-Preparation of protective layer coating liquid (1) 25 parts of D liquid, acetoacetyl-modified polyvinyl alcohol (trade name: GOHSEFIMAR (registered trademark) Z-200, manufactured by Nippon Synthetic Chemical Industry Co., Ltd., degree of polymerization: about 1000, saponification Degree: about 98 mol%) 15 parts aqueous solution 50 parts, paraffin wax (trade name: Hydrin P-7, manufactured by Chukyo Yushi Co., Ltd., solid content concentration 30%) 7.5 parts, 5% surfactant aqueous solution (trade name) : SN wet OT-70, manufactured by San Nopco) 5 parts, Glyoxal (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., solid content concentration 40%) 0.3 part, and 12.5 parts of water were mixed and stirred. A protective layer coating solution (1) was obtained.

-Preparation of anti-counterfeit recording body 1 On one side of a synthetic paper (trade name: FPG-80, manufactured by YUPO Corporation, thickness 80 μm), the coating solution for heat-sensitive recording layer (1) is used with a Mayer bar. Then, the heat-sensitive recording layer (anti-counterfeiting part) is provided by coating and drying so that the coating amount after drying is 6 g / m ^2, and the coating liquid for protective layer (1) is formed thereon using a Mayer bar. Then, the film was coated and dried so that the coating amount after drying was 3 g / m ² to provide a protective layer, whereby a forgery-preventing recording body 1 was obtained.

Example 2
-Preparation of Liquid E (Composite Fine Particle Dispersion Containing Dye Precursor Coloring in Black Color Tone) As a dye precursor coloring in black color tone, 3-di (n-butyl) amino-6-methyl- 20 parts of 7-anilinofluorane are mixed with 9.5 parts of dicyclohexylmethane-4,4′-diisocyanate (trade name: Desmodur (registered trademark) W, manufactured by Sumika Bayer Urethane Co., Ltd.), m-tetramethylxylylene diisocyanate. (Product name: TMXDI (registered trademark), manufactured by Nippon Cytec Industries, Inc.) It was dissolved in a mixed solvent consisting of 9.5 parts by heating (150 ° C.), and this solution was polyvinyl alcohol (trade name: Poval (registered trademark) PVA-217EE). 8.8 parts by Kuraray Co., Ltd. and ethylene oxide adduct of acetylene glycol as a surfactant (trade name: Olphine (registered) Mark) E1010, gradually added to Nissin Chemical Industry Co., Ltd.) solution 90 parts containing 2 parts of the day, using a homogenizer, was emulsified and dispersed by agitation speed 10000 rpm. To this emulsified dispersion, an aqueous solution in which 50 parts of water and 1.5 parts of a polyvalent amine compound (trade name: Epomin SP-006, manufactured by Nippon Shokubai Co., Ltd.) were dissolved in 13.5 parts of water was added and homogenized. This emulsified dispersion was heated to 80 ° C., subjected to a polymerization reaction for 6 hours, and a composite fine particle dispersion (Liquid E) containing a dye precursor that developed a black color with a volume average particle diameter of 0.8 μm. Prepared and diluted with water to a solids concentration of 25%.

-Preparation of thermal recording layer coating liquid (2) 6.8 parts of liquid A, 10.2 parts of liquid E, 8 parts of styrene-butadiene latex (trade name: L1571, manufactured by Asahi Kasei Corporation, solid content concentration 48%), 10 parts polyvinyl alcohol aqueous solution (trade name: Poval (registered trademark) PVA-110, manufactured by Kuraray Co., Ltd.) 40 parts, B liquid 34 parts, C liquid 17 parts, 5% surfactant aqueous solution (trade name: SN wet OT-70 A composition comprising 2 parts of Sannopco) and 17 parts of water was mixed and stirred to obtain a thermal recording layer coating solution (2).

-Preparation of anti-counterfeit recording body 2 On one side of a synthetic paper (trade name: FPG-80, manufactured by YUPO Corporation, thickness 80 μm), the above-mentioned thermal recording layer coating liquid (2) is used with a Mayer bar. Then, a heat-sensitive recording layer (anti-counterfeiting part) is provided by applying and drying so that the application amount after drying is 8 g / m ^2, and the protective layer coating liquid (1) is applied thereon using a Mayer bar. Then, the film was coated and dried so that the coating amount after drying was 3 g / m ² to provide a protective layer, whereby a forgery-preventing recording body 2 was obtained.

Example 3
Preparation of Liquid F (Composite Fine Particle Dispersion Containing Dye Precursor Coloring in Cyan Color) 3- (1-ethyl-2-methylindole-) as a dye precursor coloring in cyan color 3-yl) -3- (4-diethylamino-2-methylphenyl) -4-azaphthalide was added to 20 parts of dicyclohexylmethane-4,4′-diisocyanate (trade name: Desmodur (registered trademark) W, Sumika Bayer Urethane. 14 parts), m-tetramethylxylylene diisocyanate (trade name: TMXDI (registered trademark), manufactured by Nippon Cytec Industries, Inc.) 5 parts in a mixed solvent heated and dissolved (150 ° C.), this solution was polyvinyl alcohol ( 8.8 parts of product name: Poval (registered trademark) PVA-217EE (manufactured by Kuraray Co., Ltd.) and acetylene glyco as a surfactant Is gradually added to 90 parts of an aqueous solution containing 2 parts of ethylene oxide adduct (trade name: Orphin (registered trademark) E1010, manufactured by Nissin Chemical Industry Co., Ltd.), and emulsified and dispersed by stirring at a rotational speed of 10,000 rpm using a homogenizer. did. To this emulsified dispersion, an aqueous solution in which 50 parts of water and 1.5 parts of a polyvalent amine compound (trade name: Epomin SP-006, manufactured by Nippon Shokubai Co., Ltd.) were dissolved in 13.5 parts of water was added and homogenized. This emulsified dispersion is heated to 80 ° C., subjected to a polymerization reaction for 6 hours, and a composite fine particle dispersion (F liquid) containing a dye precursor that develops a cyan color with a volume average particle diameter of 0.8 μm. Was diluted with water to a solid content concentration of 25%.

Preparation of liquid G (developer dispersion) 40 parts of zinc salt of 3,5- (α-methylbenzyl) salicylic acid, 40 parts of 10% aqueous solution of polyvinyl alcohol (polymerization degree 500, saponification degree 88%), and water 20 parts were mixed and pulverized with an ultra visco mill until the volume average particle size became 0.80 μm to obtain a developer dispersion (liquid G).

-Preparation of thermal recording layer coating liquid (3) 41 parts F solution, 8 parts styrene-butadiene latex (trade name: L1571, manufactured by Asahi Kasei Co., Ltd., solid concentration 48%), 10% aqueous polyvinyl alcohol solution (trade name: Poval (registered trademark) PVA-110, manufactured by Kuraray Co., Ltd. 40 parts, G liquid 47 parts, 5% surfactant aqueous solution (trade name: SN Wet OT-70, San Nopco Co., Ltd.) 2 parts, and water 17 parts The composition was mixed and stirred to obtain a thermal recording layer coating solution (3).

・ Preparation of coating solution for intermediate layer 100 parts of 10% polyvinyl alcohol aqueous solution (trade name: Poval (registered trademark) PVA-110, manufactured by Kuraray Co., Ltd.), 5% surfactant aqueous solution (trade name: SN wet OT-70, San Nopco) 1 part) was mixed and stirred to obtain an intermediate layer coating solution.

-Preparation of anti-counterfeit recording body 3 On one side of a synthetic paper (trade name: FPG-80, manufactured by YUPO Corporation, thickness 80 [mu] m), the coating solution for heat-sensitive recording layer (1) is used with a Mayer bar. Then, the first heat-sensitive recording layer (anti-counterfeiting part) is provided by applying and drying so that the coating amount after drying is 6 g / m ^2, and the intermediate layer coating liquid is formed thereon using a Mayer bar, An intermediate layer is provided by coating and drying so that the coating amount after drying is 20 g / m ^2, and the coating solution for thermosensitive recording layer (3) is applied on the intermediate layer using a Mayer bar. A second heat-sensitive recording layer is provided by coating and drying so as to be 5 g / m ^2, and the coating liquid for the protective layer (1) is applied thereon using a Mayer bar so that the coating amount after drying is 3 g / m ^2. Then, a protective layer was provided by coating and drying to obtain a forgery-preventing recording body 3.

Example 4
-Preparation of Liquid H (Composite Fine Particle Dispersion Containing Dye Precursor that Colors Magenta Color) 3,3-Bis (1-n-Butyl-2-) as a Dye Precursor that Colors Magenta 20 parts of methylindol-3-yl) phthalide is added to 9.5 parts of dicyclohexylmethane-4,4′-diisocyanate (trade name: Desmodur (registered trademark) W, manufactured by Sumika Bayer Urethane Co., Ltd.), m-tetramethylxylyl A diisocyanate (trade name: TMXDI (registered trademark), manufactured by Nippon Cytec Industries, Inc.) is heated and dissolved (150 ° C.) in a mixed solvent consisting of 9.5 parts, and this solution is polyvinyl alcohol (trade name: Poval (registered trademark) PVA). -217EE (manufactured by Kuraray Co., Ltd.), 8.8 parts, and ethylene oxide adduct of acetylene glycol (trade name: OH) as a surfactant. Fin (TM) E1010, gradually added to Nissin Chemical Industry Co., Ltd.) solution 90 parts containing 2 parts of the day, using a homogenizer, was emulsified and dispersed by agitation speed 10000 rpm. To this emulsified dispersion, an aqueous solution in which 50 parts of water and 1.5 parts of a polyvalent amine compound (trade name: Epomin SP-006, manufactured by Nippon Shokubai Co., Ltd.) were dissolved in 13.5 parts of water was added and homogenized. This emulsified dispersion was heated to 80 ° C. and subjected to a polymerization reaction for 6 hours to prepare a composite fine particle dispersion (liquid H) containing a dye precursor that develops a magenta color system having a volume average particle diameter of 0.8 μm. And diluted with water so that the solid concentration was 25%.

-Preparation of thermal recording layer coating liquid (4) 41 parts of liquid H, 8 parts of styrene-butadiene latex (trade name: L1571, manufactured by Asahi Kasei Corporation, solid content concentration 48%), 10% aqueous polyvinyl alcohol solution (trade name: 40 parts PVA (registered trademark) PVA-110 (manufactured by Kuraray Co., Ltd.), 47 parts B solution, 2 parts aqueous 5% surfactant solution (trade name: SN Wet OT-70, San Nopco), and 17 parts water The composition was mixed and stirred to obtain a thermal recording layer coating solution (4).

-Preparation of anti-counterfeit recording body 4 On one side of a synthetic paper (trade name: FPG-80, manufactured by YUPO Corporation, thickness 80 [mu] m), the thermal recording layer coating liquid (1) is used with a Mayer bar. Then, the first heat-sensitive recording layer (anti-counterfeiting part) is provided by applying and drying so that the coating amount after drying is 6 g / m ^2, and the intermediate layer coating liquid is formed thereon using a Mayer bar, An intermediate layer is provided by coating and drying so that the coating amount after drying is 30 g / m ^2, and the coating solution for thermal recording layer (4) is applied on the intermediate layer using a Mayer bar. A second heat-sensitive recording layer is provided by coating and drying so as to be 5 g / m ^2, and the coating solution for heat-sensitive recording layer (3) is applied onto the second heat-sensitive recording layer using a Mayer bar so that the coating amount after drying is 4 g / m. by coating and drying so that ² providing the third heat-sensitive recording layer, the protective layer coating solution thereon to (1), main With ear bars, the coating amount after drying a protective layer by coating and drying so that 3 g / m ^2, to obtain a recording medium 4 for preventing forgery.

Example 5
・ Preparation of coating solution for protective layer (2)
A 15% aqueous solution of 21 parts of D liquid, acetoacetyl-modified polyvinyl alcohol (trade name: Gohsephimer (registered trademark) Z-200, manufactured by Nippon Synthetic Chemical Industry, degree of polymerization: about 1000, degree of saponification: about 98 mol%) 50 parts, ethylene-acrylic copolymer (trade name: Hitech S-3121, manufactured by Toho Chemical Industry Co., Ltd., solid concentration 25%), paraffin wax (trade name: Hydrin P-7, manufactured by Chukyo Yushi Co., Ltd., solid) 7.5 parts, 5% surfactant aqueous solution (trade name: SN wet OT-70, manufactured by San Nopco), glyoxal (manufactured by Nippon Synthetic Chemical Industry, solid content: 40%) A composition comprising 3 parts and 12.5 parts of water was mixed and stirred to obtain a protective layer coating liquid (2).

-Preparation of anti-counterfeit recording body 5 On one side of a synthetic paper (trade name: FPG-80, manufactured by YUPO Corporation, thickness 80 μm), the above-mentioned thermal recording layer coating liquid (1) is used with a Mayer bar. Then, the heat-sensitive recording layer (anti-counterfeiting part) is provided by coating and drying so that the coating amount after drying is 6 g / m ^2, and the protective layer coating liquid (2) is applied thereon using a Mayer bar. Then, the film was coated and dried so that the coating amount after drying was 3 g / m ^2, and a protective layer was provided to obtain the anti-counterfeit recording body 5.

Example 6
In the preparation of the liquid A of Example 1, 4- [2- (2-octyloxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzene was used as a dye precursor that develops a yellowish color tone. Forgery prevention recording in the same manner as in Example 1, except that 4- [2- (2-butoxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine was used instead of amine. Body 6 was obtained.

Example 7
In the preparation of the liquid A of Example 1, 4- [2- (2-octyloxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzene was used as a dye precursor that develops a yellowish color tone. For counterfeit prevention in the same manner as in Example 1 except that 4- [2- (2-pentyloxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine was used instead of amine. Recording material 7 was obtained.

Example 8
In the preparation of the liquid A of Example 1, 4- [2- (2-octyloxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzene was used as a dye precursor that develops a yellowish color tone. For counterfeit prevention in the same manner as in Example 1, except that 4- [2- (2-hexyloxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine was used instead of amine. A recording body 8 was obtained.

Comparative Example 1
-Preparation of liquid I (dye precursor dispersion that develops in magenta color) 3,3-bis (1-n-butyl-2-methylindole-) as a dye precursor that develops in magenta 3-yl) phthalide 40 parts, polyvinyl alcohol (polymerization degree 500, saponification degree 88%) 40% 10% aqueous solution and water 20 parts were mixed, and using a vertical sand mill (Immex Corp., sand grinder), By pulverizing and dispersing so that the volume average particle diameter becomes 1.3 μm, a dye precursor dispersion liquid (liquid I) that produces a magenta color system was obtained.

Preparation of thermal recording layer coating liquid (5) 6.8 parts of liquid I, 10.2 parts of liquid E, 8 parts of styrene-butadiene latex (trade name: L1571, manufactured by Asahi Kasei Corporation, solid content concentration 48%), 10 parts polyvinyl alcohol aqueous solution (trade name: Poval (registered trademark) PVA-110, manufactured by Kuraray Co., Ltd.) 40 parts, B liquid 34 parts, C liquid 17 parts, 5% surfactant aqueous solution (trade name: SN wet OT-70 , Manufactured by San Nopco) and a composition comprising 2 parts of water and 17 parts of water were mixed and stirred to obtain a thermal recording layer coating solution (5).

-Preparation of recording body 7 having no forgery prevention part The thermal recording layer coating liquid (5) is applied to one side of a synthetic paper (trade name: FPG-80, manufactured by YUPO Corporation, thickness 80 μm). Using a bar, the heat-sensitive recording layer was provided by coating and drying so that the coating amount after drying was 8 g / m ^2, and the protective layer coating liquid (1) was dried thereon using a Mayer bar. The protective layer was provided by applying and drying so that the subsequent coating amount was 3 g / m ^2, and the recording medium 6 having no forgery prevention part was obtained.

  The following evaluation was performed on the recording material thus obtained. The results were as shown in Table 1.

(Evaluation of fluorescence of forgery prevention part)
About the recording bodies of Examples 1 to 6 and Comparative Example 1, using a thermal tilt tester (manufactured by Toyo Seiki Co., Ltd.), the pressure was 9.8 × 10 ⁴ Pa, the contact time was 5 seconds, and the recording medium was In the range, heating was performed every 5 ° C., and it was visually evaluated whether or not the color image fluoresced by the ultraviolet irradiation of the black light.

(Print test)
For the recording materials of Examples 1, 2, 5 to 8 and Comparative Example 1, a thermal printing test apparatus and a thermal head with a recording density of 8 dots / mm (KPW-80-8TBB-1, resistance value 690Ω, manufactured by Kyocera Corporation) were used. One line recording time: 12.33 msec / line, 256 lines of solid printing was performed at an applied energy of 167.0 to 834.8 μJ / dot. With respect to the recording bodies of Examples 3 and 4, one line recording time: 12.33 msec / line, applied energy of 6.4 μJ / 1 time, pulse period of 98 μsec, and applied pulse repetition number of 109 to 124 256 lines of solid printing, low temperature color development, applied energy of 9.6μJ / 1 time, 1 pulse period of 102μsec, applying pulse repetition frequency of 110 to 120 times, medium line color printing of 256 lines solid printing Under the conditions that the applied energy was 501.9 to 834.8 μJ / 1 time and the applied pulse was repeated one time, solid printing of 256 lines was performed to perform high-temperature color development. The obtained color image was visually evaluated as to whether or not the color image fluoresces when the black light was irradiated with ultraviolet rays.

  The anti-counterfeit recording material of the present invention has a high anti-counterfeit property and is excellent in visibility. Therefore, the anti-counterfeit recording material of the present invention can be applied to prevent forgery of voting tickets, slips, securities, cash vouchers, tickets, tickets, bags, labels, and the like.

Claims (10)

  A recording medium comprising a thermosensitive coloring part containing a dye precursor and a developer on at least a part of a support, wherein the dye precursor has a pyridine skeleton in the molecular structure in at least a part of the thermosensitive coloring part And an anti-counterfeit part containing a color precursor that reacts with heating with the dye precursor having the pyridine skeleton and develops it, and the authenticity determination that the color image of the anti-counterfeit part emits fluorescence under ultraviolet light An anti-counterfeit recording material characterized in that it is recognized as information for use. The forgery-preventing recording material according to claim 1, wherein the dye precursor having the pyridine skeleton is represented by the following general formula (1).

(In the formula, R ¹ represents a hydrogen atom or an alkoxy group having 1 to 8 carbon atoms, R ² represents a hydrogen atom or an alkoxy group having 1 to 8 carbon atoms. Even if R ¹ and R ² are the same, R ³ represents an alkyl group having 1 to 4 carbon atoms.   The dye precursor having the pyridine skeleton is 4- [2- (2-butoxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine, 4- [2- (2-pentyloxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine, 4- [2- (2-hexyloxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine, 4- [2- (2-octyloxyphenyl) -6-phenyl-4-pyridinyl] -N, N-dimethylbenzenamine, 4- (2,6-diphenyl-4-pyridinyl) -N, N-dimethylbenzenamine, 4- [2,6-bis (2-butoxyphenyl) -4-pyridinyl] -N, N-dimethylbenzenamine, 4- [2,6-bis (2-pentyloxyphene) ) -4-pyridinyl] -N, N-dimethylbenzenamine, 4- [2,6-bis (2-hexyloxyphenyl) -4-pyridinyl] -N, N-dimethylbenzenamine, and 4- [2 The recording medium for forgery prevention according to claim 1 or 2, which is at least one selected from the group consisting of, 6-bis (2-octyloxyphenyl) -4-pyridinyl] -N, N-dimethylbenzenamine.   The developer contained in the forgery prevention part is 4-hydroxy-4′-isopropoxydiphenylsulfone, 4-hydroxy-4′-n-propoxydiphenylsulfone, Np-tolylsulfonyl-p-butoxycarbonylphenylurea. N- (p-toluenesulfonyl) -N ′-(3-p-toluenesulfonyloxyphenyl) urea, N- (p-toluenesulfonyl) -N′-phenylurea, 4,4′-bis [(4- Methyl-3-phenoxycarbonylaminophenyl) ureido] diphenylsulfone and 4,4′-bis (3-tosylureido) diphenylmethane are at least one selected from the group consisting of 4, Forgery prevention recording.   The thermosensitive coloring part includes a first dye precursor and a second dye precursor as the dye precursor, the first dye precursor is contained in the form of solid dispersed fine particles, and has a color tone different from that of the first dye precursor. The second dye precursor that develops color is contained in the form of composite fine particles containing the second dye precursor and the polymer compound, and either one of the first dye precursor and the second dye precursor has the pyridine skeleton. The recording material for forgery prevention according to any one of claims 1 to 4, which is a dye precursor.   The thermosensitive coloring part has a multilayer structure comprising at least a first thermosensitive recording layer and a second thermosensitive recording layer, and the first thermosensitive recording layer contains a first dye precursor in the form of solid dispersed fine particles, The second thermosensitive recording layer contains a second dye precursor in the form of composite fine particles containing a second dye precursor and a polymer compound, and one of the first dye precursor and the second dye precursor is the pyridine. The recording material for forgery prevention according to any one of claims 1 to 5, which is a dye precursor having a skeleton.   The anti-counterfeit part contains an ethylene-acrylic copolymer, or contains an ethylene-acrylic copolymer and includes a covering part adjacent to the anti-counterfeit part. The anti-counterfeit recording material described in 1.   Furthermore, the forgery prevention recording body of any one of Claims 1-7 provided with the thermal transfer receiving layer, the inkjet recording layer, the magnetic recording layer, or the adhesion layer.   A method for determining the authenticity of a forgery-preventing recording body having the structure according to any one of claims 1 to 8, wherein the forgery-preventing part of the forgery-preventing recording body is colored under heating, and the forgery-preventing part A method for identifying forgery of a forgery-preventing recording material, characterized in that a genuine image and a forgery are identified based on whether or not a colored image fluoresces when irradiated with ultraviolet rays.   By applying and drying using a coating liquid containing a dye precursor having the pyridine skeleton and a dye developer that reacts with the dye precursor having the pyridine skeleton to cause color development by heating. The forgery according to claim 1, comprising a step of providing a forgery preventing part, or a step of providing the forgery preventing part by forming an appropriate character or graphic latent image using an ink containing the composition. Method for manufacturing prevention recording material.