JPH10207003A - Photosensitive thermal recording material and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the formation of a positive type image which is recordable by using an IR laser beam, is perfectly dry, bright in blade and white and has a high contrast by using microcapsules having high heat resistance and a polymerizable monomer having properties to plasticize microcapsule wall agents in combination. SOLUTION: The photosensitive thermosensitive recording layer contains org. silver salts and the reducing agents of the org. silver salts in the form that one thereof is included in the thermally responsive microcapcules and the other is dispersed outside. Further, the microcapcules are plasticized and the compsn,. which may be cured by photoirradiation is incorporated therein. The photosetting compsn. contains a photopolymn. in initiator and the polymerizable monomer having plasticizability. The example of the more preferable photopolymn. initiator includes the org. borate salt compd. expressed by the formula. In the formula, M is an alkaline metal atom, quaternary ammonium, etc.,; (n) is an integer from 1 to 6; R<1> to R<4> are halogen atoms, substd. or unsubstd. alkyl groups, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color or black-and-white light and heat sensitive recording material using infrared laser light and a method for forming a positive image using the same.

[0002]

2. Description of the Related Art Conventionally, various dry-type image forming methods which do not use a liquid developer or the like and have no problem of waste have been studied, and among them, a method using a composition which is cured by light is used. Attention has been paid. In this method, a composition that is cured by light contained in a recording material by exposure cures to form a latent image, and components related to color development or decoloration move in the recording material according to the latent image by heating. To form a color image. Using such a recording material, the photosensitive recording material is exposed to light through an image document, and photo-cured in an exposed portion to form a latent image.
By heating the recording material, a portion relating to the coloring or decoloring of the uncured portion is moved, and this method of forming a visible image makes it possible to realize a completely dry system with no waste.

There are several types of recording materials to be used in this method, and these are characteristic methods as a black-and-white image recording method, but are particularly useful when used as a color recording material. It is. As a specific recording material, for example, a recording material disclosed in JP-A-52-89915 is known. This is achieved by separating two components of a two-component thermosensitive color recording material, for example, an electron-accepting compound and an electron-donating colorless dye, inside and / or outside or on both sides of a microcapsule containing a photocurable composition. This is the arranged recording material. However, in the case of this recording material, even if the photocurable composition in the microcapsules is sufficiently cured, the color development of the cured portion cannot be sufficiently suppressed, so that the non-image portion is slightly colored, and the contrast tends to be poor. There is.

As a more preferable recording material having no coloring in the non-image area, for example, as disclosed in JP-A-61-123838, a photopolymerization comprising a vinyl monomer having an acidic group and a photopolymerization initiator is disclosed. There is known a recording material in which a layer containing a hydrophilic composition, a separating layer, and a layer composed of an electron-donating colorless dye are laminated. In the case of this recording material, the non-image portion, that is, the thermal curing property of the acidic group in the portion cured by the photopolymerized portion is almost eliminated, so that the non-image portion is not colored, but the coloring density is slightly low. As a method of obtaining a negative image by the same method, for example, there is a method disclosed in JP-A-60-119552. This method uses a photopolymerizable composition comprising a monomer or prepolymer for bleaching a dye and a photopolymerization initiator, and a recording material in which a dye bleached by the monomer or the prepolymer is present in isolation. This recording material also has the same disadvantages as the above-mentioned recording material.

As a preferable recording material capable of overcoming the coloring of the non-image area and the low image density, the present applicant has previously proposed JP-A-3-87827 and JP-A-4-21252. In the former recording material, one of the two components of the one-component type thermosensitive color recording material is encapsulated in a microcapsule, and the other component is used as a curable compound of a photocurable composition, or the other component is used as a photocurable composition. It is a recording material arranged outside the microcapsule together with the material, the latter recording material, the electron-accepting compound, a photocurable composition containing a polymerizable vinyl monomer and a photopolymerization initiator is arranged outside the microcapsule This is a recording material provided with a layer containing a microcapsule containing an electron-donating colorless dye.

Although these recording materials can be applied to various uses, they all use UV light and short-wave visible light, and cannot use a small and inexpensive red laser or infrared laser.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to perform recording using an infrared laser beam, to eliminate the use of a developing solution and the like, to generate no unnecessary waste, and to realize a completely dry recording medium. An object of the present invention is to provide a light- and heat-sensitive recording material capable of forming a positive and negative black-and-white image with high contrast, and an image forming method using the same.

[0008]

Means for Solving the Problems As a result of intensive studies, the inventors of the present invention have found that the above-mentioned object is to provide a microcapsule having high heat resistance and a polymerizable monomer having physical properties to plasticize the microcapsule wall material. It has been found that the present invention can be achieved by a light and heat sensitive recording material using a combination of the above and has completed the present invention. That is, the light and heat sensitive recording material of the present invention is:
In a light and heat sensitive recording material having a light and heat sensitive recording layer provided on a support, the light and heat sensitive recording layer contains an organic silver salt and a reducing agent of an organic silver salt, and one of the two is encapsulated in a thermoresponsive microcapsule. The other is contained in a form dispersed outside the thermoresponsive microcapsules, and further contains a composition that plasticizes the thermoresponsive microcapsules and can be cured by light irradiation. In the present specification, the “photosensitive material” will be referred to as “recording material”, the “photosensitive material” will be referred to as “recording layer”, the “thermoresponsive microcapsules will be plasticized, and The composition which can be cured by the method is referred to as "photocurable composition".

Here, the photocurable composition is characterized by containing a photopolymerization initiator and a polymerizable monomer having a plasticizing ability, and the photopolymerization initiator is an organic borate salt compound. The polymerizable monomer having a plasticizing ability is a polymerizable vinyl monomer containing a phenol group.

The photocurable composition preferably contains a spectral sensitizing dye such as an infrared absorbing dye.

Further, in the image forming method of the present invention, the photosensitive and heat-sensitive recording material is exposed imagewise by an exposing means, and the entire surface of the exposed recording material is uniformly heated by a heating means. An image is formed. It is preferable to use infrared laser light as the exposure means.

In the light- and heat-sensitive recording material of the present invention, the dispersed photocurable composition is cured and fixed in the imagewise exposed portion. Effective contact with the capsule wall is prevented and the capsule wall maintains a high glass transition temperature. Therefore, even if the predetermined heating is performed, the property of plasticizing the thermoresponsive microcapsules cannot be exhibited, and the organic silver salt and the developer remain separated by the capsule wall material, and no color image is generated. On the other hand, in the non-exposed area, the thermo-responsive microcapsule plasticizes, and the composition that is cured by light irradiation contacts the capsule wall material and plasticizes the wall material, and the glass transition temperature of the capsule wall material decreases. By heating, thermal contact between the organic silver salt or the developer contained in the capsule and the developer or the organic silver salt dispersed outside the capsule is performed, and the development (color-forming reaction) proceeds, based on the exposure. A positive type image is formed.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail.

In the present invention, the photocurable composition contains a photopolymerization initiator and a polymerizable monomer having a plasticizing ability, and can plasticize the capsule wall material such as polyurea or polyurethane contained therein. As the polymerizable monomer that is cured by light, any compound containing a hydrogen bonding group and a vinyl group may be used. Examples of such a compound include methacryloxyethyl ester of benzoic acid having a hydroxy group described in JP-A-63-173682, acryloxyethyl ester which can be synthesized by a similar synthesis method, and JP-A-59-83693. 60-14
1587, esters of hydroxymethyl-containing benzoic acid and hydroxymethylstyrene described in JP-A-62-99190, hydroxystyrene described in EP 29323, JP-A-62-167077,
N-vinylimidazole complexes of zinc halides described in JP-A-62-16708 and JP-A-63-317558.
Various compounds that can be synthesized with reference to the developer monomer described in the above publication can be used.

Specific examples include, for example, styrenesulfonylaminosalicylic acid, vinyl benzyloxyphthalic acid,
β-methacryloxyethoxysalicylate, β-acryloxyethoxysalicylate, vinyloxyethyloxybenzoic acid, β-methacryloxyethylorselinate, β-acryloxyethylorselinate, β-methacryloxyethoxyphenol, β- Acryloxyethoxyphenol, β-methacryloxyethyl-β-resorcinate, β-acryloxyethyl-β-resorcinate, hydroxystyrenesulfonic acid-N-ethylamide, β-methacryloxypropyl-p-hydroxybenzoate, β-acryloxypro Bil-p-hydroxybenzoate, methacryloxymethylphenol, acryloxymethylphenol, methacrylamidopropanesulfonic acid, acrylamidopropanesulfonic acid, β-
Methacryloxyethoxy-dihydroxybenzene, β-
Acryloxyethoxy-dihydroxybenzene, γ-styrenesulfonyloxy-β-methacryloxypropanecarboxylic acid, γ-acryloxypropyl-α-hydroxyethyloxysalicylic acid, β-hydroxyethoxycarbonylphenol, β-methacryloxyethyl-p-
Hydroxycinnamate, β-acryloxyethyl-p
-Hydroxycinnamate, 3,5-distyrenesulfonic amide phenol, methacryloxyethoxyphthalic acid, acryloxyethoxyphthalic acid, methacrylic acid, acrylic acid, methacryloxyethoxyhydroxynaphthoic acid, acryloxyethoxyhydroxynaphthoic acid, 3-
β-hydroxyethoxyphenol, β-methacryloxyethyl-p-hydroxybenzoate, β-acryloxyethyl-p-hydroxybenzoate, β′-methacryloxyethyl-β-resorcinate, β-methacryloxyethyloxycarbonylhydroxybenzoic acid, β
-Acryloxyethyloxycarbonylhydroxybenzoic acid, N, N′-di-β-methacryloxyethylaminosalicylic acid, N, N′-di-β-acryloxyethylaminosalicylic acid, N, N′-di-β-methacrylic acid Roxyethylaminosulfonylsalicylic acid, N, N'-di-β-
Acryloxyethylaminosulfonylsalicylic acid and the like, and metal salts thereof such as zinc salt can be preferably used.

The photopolymerization initiator suitably used in the recording material of the present invention can be selected from one or more compounds capable of initiating the photopolymerization of the vinyl monomer. . Preferred specific examples of the photopolymerization initiator include an organic borate salt-based compound represented by the following general formula (1).

The organic borate salt-based compound generates a radical based on the irradiated laser beam, and the radical initiates the polymerization of the polymerizable monomer contained in the photopolymerizable composition.

[0018]

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Here, M is an alkali metal atom, quaternary ammonium, pyridinium, quinolinium, diazonium, morpholinium, tetrazolium, acridinium, phosphonium, sulfonium, oxosulfonium, sulfur, oxygen, carbon, halogenium, Cu, Ag, H
g, Pd, Fe, Co, Sn, Mo, Cr, Ni, A
s and Se, n represents an integer of 1 to 6, and R ¹ , R ² , R
³ and R ⁴ may be the same or different and include a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted alkaryl group, Or an unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alicyclic group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted allyl group, a substituted or unsubstituted silyl group R ¹ , R ² ,
R ³ and R ⁴ may be combined with each other to form a cyclic structure.

Preferred examples of the borate anion include, for example, tetramethyl borate, tetraethyl borate,
Tetrabutyl borate, triisobutyl methyl borate, di-n-butyl-di-t-butyl borate, tetra-n-butyl borate, tetraphenyl borate, tetra-p-chlorophenyl borate, tetra-m-chlorophenyl borate, tri-m -Chlorophenyl-n-hexyl borate, triphenylmethyl borate, triphenylethyl borate, triphenylpropyl borate, triphenyl-n-butyl borate, trimesityl butyl borate, tolyl isopropyl borate, triphenyl benzyl borate, tetraphenyl borate, Tetrabenzyl borate, triphenylphenethyl borate, triphenyl-p-chlorobenzyl borate, triphenylethenylbutyl borate, di (α-naphthyl) -dipropyl borate DOO, triphenylsilyl triphenyl borate, preparative Little yl silyl triphenyl borate, tri -n- butyl (dimethylphenylsilyl) borate, and the like.

Specific examples of the organic borate salt represented by the general formula (1) according to the present invention are shown below. However, the effects of the present invention are not limited to the following compounds.

[0022]

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[0023]

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[0024]

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The content of the photopolymerization initiator is preferably from 0.01 to 20% by weight, and more preferably from 0.2 to 15% by weight, based on the total weight of the photocurable composition, and most preferably the content is The amount is between 1 and 10% by weight. 0.01% by weight
If it is less than 10%, the sensitivity is insufficient. If it exceeds 10% by weight, an increase in sensitivity cannot be expected.

Further, the organic borate salt in the present invention is preferably used in combination with a spectral sensitizing dye, and in particular, may be used in combination with a red light absorbing dye or an infrared absorbing dye.
It is preferable from the viewpoint of increasing the laser absorption efficiency.

In the present invention, if desired, the maximum absorption wavelength used in combination with the organic borate salt is 500 to 1100 n.
Examples of the infrared absorbing dye having a wavelength region of m include cationic dyes, and are dyes selected from cationic methine dyes, polymethine dyes, triarylmethane, indoline, azine, xanthene, oxazine, and acridine dyes. Is preferred.

Further, it is preferred that the cationic dye is a dye selected from cationic cyanine, hemicyanine, rhodamine and azamethine dyes.

As the cationic dye (spectral sensitizing dye) that can be used in the present invention, any organic cationic dye having an absorption peak in the wavelength region of 500 nm or more, preferably 500 to 1100 nm, is preferably used. be able to.

Examples of the organic cationic dye which can be used in the present invention include a cationic methine dye, a cationic carbonium dye, a cationic quinone imine dye, a cationic indoline dye, and a cationic styryl dye. As the methine dye, preferably a polymethine dye, a cyanine dye, an azomethine dye,
More preferably cyanine, carbocyanine, dicarbocyanine, tricarbocyanine, hemicyanine and the like, as the cationic carbonium dye, preferably a triarylmethane dye, xanthene dye, alicidine dye,
More preferably rhodamine and the like, as the cationic quinone imine dye, preferably a dye selected from azine dyes, oxazine dyes, thiazine dyes, quinoline dyes, thiazole dyes and the like, and these are used alone or in combination of two or more. Can be used.

Many organic cationic dye compounds having an absorption peak in the wavelength region of 500 nm or more are known. For example, "Functional dye chemistry"
1981, CMC Publishing Co., pp. 393-416, and "Coloring Materials", 60 [4] 212-224 (1987).

It is also possible to add, in the side-decomposition reaction, a salt which has been formed in advance with these organic cationic dyes and organic borate ions.

Further, a thermal polymerization inhibitor can be added to the photocurable composition as needed. The thermal polymerization inhibitor is added to prevent the photocurable composition from undergoing ripening polymerization or polymerization with time, and thereby, the chemical stability during the preparation and storage of the photocurable composition. Can be increased. Examples of thermal polymerization inhibitors include p-methoxyphenol, hydroquinone, t-butylcatechol, pyrogallol, 2-hydroxybenzophenone, 4-methoxy-
2-hydroxybenzophenone, cuprous chloride, phenothiazine, chloranil, naphthylamine, β-naphthol, 2,6-di-t-butyl-p-cresol, nitrobenzene, dinitrobenzene, picric acid, p-toluidine and the like. The preferable addition amount of the thermal polymerization inhibitor is 0.001 to 5% by weight, more preferably 0.01 to 1% by weight based on the total weight of the photocurable composition. If it is less than 0.001% by weight, the thermal stability is poor, and if it exceeds 5% by weight, the sensitivity decreases.

The photocurable composition of the recording material of the present invention is emulsified and dispersed and contained in the photosensitive and heat-sensitive layer. At this time, a natural oil or a synthetic oil can be used as a solvent for dissolving each material contained in the photocurable composition. Examples of these solvents include cottonseed oil, kerosene, aliphatic ketones, aliphatic esters, paraffins, naphthenic oils, alkylated biphenyls, alkylated terphenyls, chlorinated paraffins, alkylated naphthalenes and 1-phenyl-1-.
Diarylethanes such as xylylethane, 1-phenyl-1-p-ethylphenylethane, 1,1′-ditolylethane; Phthalic acid alkyl ester (dibutyl phthalate, dioctyl phthalate, dicyclohexyl phthalate, etc.), phosphate ester (diphenyl phosphate, triphenyl phosphate, tricresyl phosphate, dioctyl butyl phosphate, etc.) citrate (eg, tributyl acetyl citrate) Benzoic acid esters (e.g., octyl benzoate), alkylamides (e.g., diethyl laurylamide), trimesic acid esters (e.g., tributyl trimesic acid), acetate esters (ethyl acetate, propyl acetate, iso-propyl acetate),
Butyl acetate, tert-butyl acetate, s-butyl acetate, etc.), propionate ester (eg, propionate ester), butyric acid (isobutyrate) ester (eg, methyl butyrate), acrylic acid (methacrylic acid) ester (eg, methyl acrylate) , Alkyl halides (methylene chloride, carbon tetrachloride, etc.), tertiary butyl alcohol, thimer isobutyl ketone, β-ethoxyethyl acetate, methyl cellosolve acetate, cyclohexanone and the like. Of these, aliphatic esters and alkyl halides are preferred, and those having a solubility in water of 10% by volume or less are more preferred. These solvents are preferably used in a proportion of 1 to 500 parts by weight based on the polymerizable monomer.

As the water-soluble polymer which can be used for emulsifying and dispersing the photocurable composition of the present invention, a compound which is soluble in water at 25 ° C. in an amount of 5% by weight or more is preferable. Gelatin derivatives, proteins such as albumin and casein, cellulose derivatives such as methylcellulose and carboxymethylcellulose, sugar derivatives such as sodium alginate, starches (including modified starch), gum arabic, polyvinyl alcohol, and styrene-maleic anhydride copolymers Decomposition products, carboxy-modified polyvinyl alcohol, polyacrylamide, saponified products of vinyl acetate-polyacrylic acid copolymers, and synthetic polymers of polystyrene sulfonate sugars. Among these, gelatin and polyvinyl alcohol are preferred.

The organic silver salt contained in the recording layer of the light- and heat-sensitive recording material of the present invention is a colorless or white silver salt that is stable to light, and when heated with a developer, undergoes an oxidation-reduction reaction. Produces silver. Such an organic silver salt is a silver salt of an organic compound having an imino group, a mercapto group or a carboxyl group, and specific examples thereof include the following.

1) Silver salt of organic compound having imino group Silver saccharin, silver phthalazinone, silver benzotriazole, etc. 2) Silver salt of organic compound having mercapto group or thione group 3- (2-carbonylethyl) -4-oxy Methyl-4
-Silver salt of thiazoline-2-thione, 3-mercapto-4
Silver salts of organic compounds having a carboxyl group, such as silver stearate and silver behenate.

Among them, from the viewpoints of being white and stable to light, being excellent in moisture resistance, being usable in combination with a mild developer, and being known for excellent color toning agents, Silver behenate is most preferred.

In the recording material of the present invention, it is preferable to use a desalted and purified organic silver salt from the viewpoint of recording a high density image using a high density organic silver salt. Here, desalination purification means, for example, when preparing an organic silver salt by adding silver nitrate to a salt of an organic acid formed by adding an alkali to an organic acid, a nitrate salt by-produced by the addition of the silver nitrate Is to be removed from the system. Such desalting purification is preferably performed by an ultrafiltration method using a semipermeable membrane that allows the passage of nitrate but not the organic silver salt, or a centrifugation method.

When the silver halide is contained adjacent to the organic silver salt, the silver halide is contained in the system in which the organic silver salt is present, but a part of the organic silver salt is halogenated by adding a silver halide forming agent. It is preferable to contain it by changing it to silver.

As the silver halide forming agent, CaB
inorganic halides such as r ₂ , KBr, KCl and HBr; onium halides such as NH ₄ Br and NH ₄ Cl;
Examples thereof include halogen-donating compounds such as halogenated carbon and N-halides such as N-bromosuccinimide.

When silver halide is used in combination, the content is preferably 1 to 30 mol% based on the organic silver salt.

Next, the organic silver salt developer will be described.
The developer used in the recording material of the present invention is a reducing agent having an action of reducing an organic silver salt to generate silver when heated, and rapidly reacting at a developing temperature to reduce the image. Characteristics such as not affecting the color tone are required.

Examples of such a developer include hydroxycoumarone or hydroxycoumarins, sulfamidophenols or sulfamidonaphthols, hydradones, hirooxamic acids, bis-β-naphthols, indane-1,3. -Diones, aminophenols or aminonaphthols, pyrazolin-5-ones, hydroxylamines, reductones, hydrazines, hydroquinones, bisphenol A, bisphenol B
Such as polyphenols, gallic acid, gallic acid ester,
Phenylenediamines, hydroxyindanes, 1,4
-Dihydroxypyridines, amide oximes, hydroxy-substituted aliphatic carboxylic acid aryl hydrazides, N-
Hydroxyureas, phosphonamidophenols, phosphonamidoanilines, α-cyanophenylacetic esters, sulfonamidoamilines and the like, among these, each compound represented by the following formula, octyl gallate, It is preferable to use propyl gallate, ethyl gallate or methyl gallate.

[0045]

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In the light and heat sensitive recording material of the present invention, one of the organic silver salt and its reducing agent is encapsulated in microcapsules made of polyurea, polyurethane or the like, and the other is dispersed outside the capsule. is necessary. Encapsulating either the organic silver salt or the organic silver salt developer in the microcapsule can prevent the reduction reaction between the organic silver salt and the developer at room temperature, extend the shelf life of the recording material, and fog over time. It is also preferable from the viewpoint of reducing the amount.

When one of the organic silver salt and the organic silver salt developer is microencapsulated, the other is used by dispersing it in a solid, completely dissolved in an aqueous solution of polyvinyl alcohol or the like, or dissolved in an organic solvent. After being converted into an oil phase, the oil phase can be mixed with an aqueous phase containing a water-soluble polymer and used in the form of an emulsified dispersion. In the latter case, the recording layer can be made transparent. Examples of the method of solid dispersion of the organic silver salt include, for example, a water-soluble polymer compound such as an organic silver salt and polyvinyl alcohol, and a color tone agent, an antifoggant, a dispersant, water and the like, if necessary, a ball mill, It is dispersed to several microns or less by a sand mill or the like. On the other hand, the developer is similarly solid-dispersed or completely dissolved in an aqueous solution such as polyvinyl alcohol. The liquids thus obtained may be blended to prepare a solid dispersion coating liquid, which may be coated on a support and used.

The microcapsules usable in the present invention are:
It is a thermo-responsive microcapsule that isolates a substance contained at room temperature, is not destroyed by pressure, heat, or the like at the time of heating, and makes the wall of the microcapsule material-permeable.

As a method for producing such microcapsules, known production methods such as an interfacial polymerization method, an internal polymerization method, and an external polymerization method can be employed. In particular, organic silver salts or organic silver salts can be used. An oil phase component obtained by adding a capsule wall material (polymer material) to a core material obtained by dissolving or dispersing a developer in an organic solvent is emulsified in an aqueous solution in which a water-soluble polymer is dissolved. It is preferable to adopt an interfacial polymerization method in which a wall made of the polymer of the capsule wall material is formed around the capsule wall.

As the organic solvent, it is preferable to use a non-aqueous solvent having a boiling point of 150 ° C. or less, such as a carboxylic acid ester such as ethyl acetate, butyl acetate and isoamyl acetate, toluene, xylene and phosphate ester.

The reactant forming the capsule wall material is added inside the oil droplet and / or outside the oil droplet.

Specific examples of the capsule wall material include polyurethane, polyurea, polyamide, polyester, polycarbonate, urea-formaldehyde resin, polyamic acid, polystyrene, styrene methacrylate copolymer, styrene-acrylate copolymer and the like.
Preferred capsule wall materials are polyurethane, polyurea, polyamide, polyester, and polycarbonate, and polyurethane and polyurea are preferred because capsules that are hard to break are obtained. These polymer substances can be used in combination of two or more kinds.

Specific examples of the water-soluble polymer include gelatin, polyvinylpyrrolidone, and polyvinyl alcohol.

For example, when polyurea or polyurethane is used as the capsule wall material, (a) a polyvalent isocyanate such as diisocyanate, triisocyanate, tetraisocyanate, or polyisocyanate prepolymer; and (b) diamine , Triamine, tetraamine and other polyamines, prepolymers containing two or more amino groups, piperazine or its derivatives, polyhydric alcohols and the like, or water in an aqueous solvent by an interfacial polymerization method to easily form microcapsule walls. Can be formed. The microcapsules in this case are preferable because their walls are dense.

For the composite wall composed of polyurea and polyamide or the composite wall composed of polyurethane and polyamide, for example, the pH of an emulsifying medium serving as a reaction solution is adjusted using polyisocyanate and acid chloride or polyamine and polyhydric alcohol. Thereafter, it can be prepared by heating. For details of the method for producing a composite wall composed of these polyurea and polyamide, see JP-A-58-1983.
-66948. The capsule made of polyamic acid is formed, for example, by an interfacial reaction between a polystyrene-maleic anhydride copolymer and a polyvalent amine.

The following isocyanate compounds are particularly preferable wall materials of the microcapsules used in the recording material for infrared laser of the present invention.

The isocyanate-based compound used herein includes known isocyanate monomers (1) urethane-modified, (2) allophanate-modified, (3) isocyanurate-modified, (4) buret-modified, and (5) ) Modified carbodiimides, (6) modified products such as blocked isocyanates, and (7) polymeric MDI,
Linear polymer of 4'-diphenylmethane diisocyanate (MDI).

As the isocyanate monomer forming the modified product, tolylene diisocyanate (TDI), 4,4
4'-diphenylmethane diisocyanate (MDI),
Xylylene diisocyanate (XDI), naphthylene diisocyanate (NDI), paraphenylene diisocyanate (PPDI), tetramethyl xylylene diisocyanate (TMXDI), hexamethylene diisocyanate (HDI), dicyclohexylmethane diisocyanate (HMDI), isophorone diisocyanate (IP
DI), lysine diisocyanate (LDI), isopropylidene bis (4-cyclohexyl isocyanate)
(IPC), hydrogenated xylylene diisocyanate (hydrogenated X
DI), cyclohexyl diisocyanate (CHD
I) and tolidine diisocyanate (TODI). The structure of this isocyanate monomer is shown below, but the isocyanate monomer used in the present invention is not limited to these. These are described in detail, for example, in "Synthesis, blending, functionalization and application development of latest polyurethane" (Technical Information Association, 1989).

[0059]

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[0060]

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These isocyanate monomers are used after being modified into various isocyanate modified products as described above for the purpose of improving undesirable physical properties such as toxicity, controlling the reaction rate, and improving the mixing ratio. Can be Next, the modified form will be described. (1) The urethane-modified product is obtained by modifying an isocyanate monomer (or diisocyanate) with a shortage of polyol. (2) The modified allophanate is formed by adding an isocyanate group to a urethane group. (3) The modified isocyanurate has an isocyanurate ring in the molecule and tends to have improved heat resistance. (4) The modified buret is a compound in which an isocyanate group is added to a urea bond, and is a compound from which free isocyanate is removed. (5) In the modified carbodiimide, a carbodiimide bond is generated from a 2 mol isocyanate group by a decarbonation reaction. Furthermore, after uretonimine is formed when the isocyanate is added, carbodiimide and uretonimine coexist in equilibrium. (6) Blocked isocyanate is obtained by reacting various blocking agents to temporarily mask the activity of the isocyanate group.
Phenolic blocking agents such as xylenol, oximes,
Active hydrogen compounds such as lactams and alcohols are exemplified.

Specific examples of the capsule wall material of the recording material for an infrared laser of the present invention include isocyanate compounds represented by the following formulas (a) to (k) from the viewpoint of safety and availability. .

[0063]

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[0064]

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The reactant forming the capsule wall material is preferably heated after emulsification and dispersion. The heating conditions are preferably 30 to 80 ° C. for 30 minutes to 4 hours. If the temperature is lower than 30 ° C., the reaction requires a long time and the reaction proceeds only incompletely. When the temperature exceeds ℃, it becomes difficult to control the reaction, which is not preferable.

For example, when an isocyanate compound is used as a capsule wall material, an oil phase component obtained by further adding at least one isocyanate compound to a dispersion obtained by dispersing an organic silver salt in the organic solvent as described above. After being added to an aqueous solution containing a water-soluble binder such as gelatin,
Stirring is performed to obtain a dispersion in which the oil phase component is dispersed in an aqueous solution, and the entire dispersion is heated to, for example, about 40 to 90 ° C. to form a wall material of microcapsules.

At this time, the average particle size of the obtained microcapsules is preferably 0.1 to 3.0 μm.
More preferably, it is 0.2 to 1.2 μm. By controlling the particle diameter in the above range, the transparency of the recording layer is improved, and there are advantages such that an image can be observed with transmitted light in a sharkstain.

For microencapsulation in the recording material of the present invention, a method known in the art can be used. For example, a method using a coacervation of a hydrophilic wall forming material as disclosed in U.S. Pat. Nos. 2,800,457 and 2,800,458, U.S. Pat. No. 3,287,154, British Patent No. 990443, JP-B-38-19574, and 42.
Interfacial polymerization method as disclosed in U.S. Pat. Nos. 3,446,504 and 3,660,304.
By precipitation of polymer found in US Pat.
No. 796,669, using an isocyanate polyol wall material, US Pat. No. 3,914,511, using an isocyanate wall material, US Pat.
001140, 4087376, 408980
No. 2, urea-formaldehyde type, a method using a urea formaldehyde-resorcinol type wall-forming material, US Pat.
A method using a wall-forming material such as formaldehyde resin and hydroxybromocellulose, JP-B-36-9168.
JP-A-952807, UK Patent No. 952807, and JP-A-51-9079.
The electrolytic dispersion cooling method disclosed in U.S. Patent No. 965074 and the spray drying method disclosed in U.S. Patent No. 3,111,407 and British Patent No. 930422. Although not limited thereto, it is preferable to form a polymer film as a microcapsule wall after emulsifying the core substance.

The method of forming the microcapsule wall of the recording material of the present invention is particularly effective when a microencapsulation method is used in which a reactant is polymerized from inside oil droplets. That is, it is possible to obtain a capsule having a uniform particle size in a short time, and which is preferable as a recording material having excellent raw preservability. For example, when polyurethane is used as a capsule wall material, a polyvalent isocyanate and, if necessary, a second substance (eg, polyol or polyamine) which reacts with the polyisocyanate to form a capsule wall are mixed in an oily liquid to be encapsulated and emulsified in water. By dispersing and then raising the temperature, a polymer forming reaction occurs at the oil droplet interface to form microcapsule walls. At this time, an auxiliary solvent having a low boiling point and strong dissolving power can be used in the oily liquid. In this case, the polyvalent isocyanate to be used and the polyol and polyamine to be reacted therewith are described in US Pat.
No. 1383, No. 3773695, No. 3793268
No., JP-B-48-40347, JP-B-49-24159
And JP-A-48-80191 and JP-A-48-84086, and they can also be used. Examples of the polyvalent isocyanate include m-phenylene diisocyanate, p-phenylene diisocyanate,
2,6-tolylene diisocyanate, 2,4-tolylene diisocyanate, naphthalene-1,4-diisocyanate, diphenylmethane-4,4-diisocyanate,
3,3'-dimethoxy-4,4'-biphenyl-diisocyanate, 3,3'-dimethyldiphenylmethane-
4,4'-diisocyanate, xylylene-1,4-diisocyanate, 4,4'-diphenylpropane diisocyanate, trimethylene diisocyanate, hexamethylene diisocyanate, propylene-1,2-diisocyanate, butylene-1,2-diisocyanate, cyclohexyl Diisocyanates such as silene-1,2-diisocyanate and cyclohexylene 1,4-diisocyanate; triisocyanates such as 4,4 ′, 4 ″ -triphenylmethane triisocyanate and toluene-2,4,6-triisocyanate; Tetraisocyanate such as 4,4'-dimethyldiphenylmethane-2,2 ', 5,5'-tetraisocyanate, adduct of hexamethylene diisocyanate and tremethylolpropane,
There are isocyanate prepolymers such as adducts of 2,4-tolylene diisocyanate and trimethylolpropane, adducts of xylylene diisocyanate and trimethylolpropane, and adducts of tolylene diisocyanate and hexanetriol.

Examples of the polyol include aliphatic and aromatic polyhydric alcohols, hydroxypolyesters, and hydroxypolyalkylene ethers. JP-A-60-
The following polyols described in No. 49991 can also be used. Ethylene glycol, 1,3-propanediol,
1,4-butanediol, 1,5-pentanediol,
1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, propylene glycol, 2,3-dihydroxybutane, 1,2-dihydroxybutane, 1,3-dihydroxybutane, 2,2-dimethyl -1,3-propanediol, 2,4-pentanediol, 2,5-hexanediol, 3-methyl-1,
5-Bentanediol, 1,4-cyclohexanedimethanol, dihydroxycyclohexane, diethylene glycol, 1,2,6-trihydroxyhexane, 2-phenylpropylene glycol, 1,1,1-trimethylolpropane, hexanetriol, pentaerythritol Pentaerythritol ethylene oxide adduct, glycerin ethylene oxide adduct, glycerin, 1,4-di (2-hydroxyethoxy) benzene,
Condensation product of aromatic polyhydric alcohol such as resorcinol dihydroxyethyl ether and alkylene oxide, p-xylylene glycol, m-xylylene glycol, α, α′-dihydroxy-p-diisopropylbenzene, 4,4′-dihydroxy -Diphenylmethane,
Examples thereof include 2- (p, p'-dihydroxydiphenylmethyl) benzyl alcohol, an adduct of ethylene oxide with bisphenol A, and an adduct of propylene oxide with bisphenol A. The polyol is preferably used in a ratio of 0.02 to 2 mol of the hydroxyl group to 1 mol of the isocyanate group.

Examples of the polyamine include ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, p-phenylenediamine, m-phenylenediamine, piperazine, 2-methylpiperazine, 2,5-dimethylpiperazine, Examples thereof include 2-hydroxytrimethylenediamine, diethylenetriamine, triethylenetriamine, triethylenetetramine, diethylaminopropylamine, tetraethylenepentamine, and amine adducts of epoxy compounds. Polyvalent isocyanates can also react with water to form polymeric substances.

When producing microcapsules, a water-soluble polymer can be used as a protective colloid, and the water-soluble polymer may be any of a water-soluble anionic polymer, a nonionic polymer, and an amphoteric polymer. Examples of the anionic polymer, either natural can be used even be synthetic, for example -COO -, - SO ₂ - include those having a group. Specific examples of anionic natural polymers include arabic gum, alginic acid, and vectin.Semi-synthetic products include carboxymethyl cellulose, gelatin derivatives such as phthalated gelatin, sulfated starch, sulfated cellulose, and ligninsulfonic acid. is there. In addition, as synthetic products, maleic anhydride-based (including hydrolyzed) copolymers, acrylic acid-based (including methacrylic acid-based)
There are polymers and copolymers, vinylbenzenesulfonic acid-based polymers and copolymers, carboxy-modified polyvinyl alcohol, and the like. Examples of the nonionic polymer include polyvinyl alcohol, hydroxyethyl cellulose, and methyl cellulose. Examples of the amphoteric compound include gelatin.
Among them, gelatin, gelatin derivatives and polyvinyl alcohol are preferred. These water-soluble polymers are 0.0
Used as an aqueous solution of 1 to 10% by weight. The average particle size of the capsule used in the recording material of the present invention is 20 μm or less, and particularly preferably 5 μm or less from the viewpoint of resolution. If the capsule is too small, the surface area for a certain solid content becomes large, and a large amount of wall material is required. Therefore, the thickness is preferably 0.1 μm or more.

The water-soluble binder used in the present invention has a function of binding the developer and the microcapsules contained in the recording layer and a function of adhering the recording layer to the support. Examples of such a water-soluble binder include gelatin and / or a gelatin derivative (for example, phthalated gelatin), a water-soluble polymer such as polyvinyl alcohol, methylcellulose, carboxymethylcellulose, hydroxypropylcellulose, arabic gum, polyvinylpyrrolidone, casein, styrene- Examples include various emulsions such as butadiene latex, acrylonitrile-butadiene latex, polyvinyl acetate, polyacrylate, and ethylene-vinyl acetate copolymer.

The amount of the binder used is preferably 0.5 to 5 g / m ² in terms of solid content.

In the present invention, from the viewpoint of accelerating the reduction reaction between the organic silver salt and the developer at the time of heating, adjusting the color tone of the image and performing rapid development, a development accelerator (color tone agent) is used.
Is preferably contained in the recording layer.

This development accelerator is preferably used when the resulting image is desired to be a dark image, particularly a black image. The amount used ranges from about 0.0001 mol to about 2 mol, preferably from about 0.0005 mol to about 1 mol, per 1 mol of the organic silver salt. Effective development accelerators vary with the organic silver salt and developer used, but the most common development accelerators are heterocyclic organic compounds containing at least two heteroatoms, wherein the heterocycle contains At least one nitrogen atom is present.

These are described, for example, in US Pat.
No. 0,254. Specific examples of such a development accelerator include, for example, phthalazone (phthalazinone), anhydrous phthalates, 2-acetylphthalazinone,
2-phthalylphthalazinone and others, JP-A-50-67
Examples include substituted phthalazinones described in JP-A-132, which are preferably used in the present invention.

Examples of other effective development accelerators include pyrazolin-5-ones, cyclic imides, and quinazolinones as described in JP-A-46-6077. Specific examples of these include phthalimide, N-hydroxyphthalimide, N-potassium phthalimide, and silver phthalimide. Alternatively, phthalazinones are also effective as development accelerators.

Other effective development accelerators are disclosed in
And mercapto compounds as described in JP-A Nos. 9-5019 and 49-5020. Other examples include oxazinediones described in JP-A-50-2542, phthalazinediones described in JP-A-50-67641, and 58-114217.
Uracils as described in U.S. Pat. No. 3,782,941 as described in U.S. Pat. No. 3,782,941.
Hydroxyhydroxyphthalimides, as described in West German Patent Application Publication Nos. 2,140,406, 2,141,063 and 2,220,597.
Substituted phthalimides, West German Patent Application Publication No. 2,22
Phthalazinone derivatives, such as those described in U.S. Pat. No. 0,618, can be used as well.

In the recording material of the present invention, it is preferable to take the following measures from the viewpoint of preventing heat fogging and stabilizing the background after image formation.

First, it is well known that mercury compounds are very effective in preventing thermal fog and stabilizing the background after image formation. However, from the viewpoint of environmental pollution, it is difficult to use these compounds. Since it is not preferable, in the present invention, JP-A-49-10724, JP-A-48-2842,
N, as described in JP-A-48-8194,
It is preferred to use N-halogeno compounds such as -halogenosuccinimide, N-halogenoacetamide, N-halogenoxazolinone, N-halogenobenzotriazole, and N-halogenobenzimidazole.

Also, US Pat. No. 3,645,739, JP-A-49-125016 and JP-A-49-1307
No. 20, 50-57619, 50-39264, etc .; higher fatty acids; arylsulfonates such as tetrahalogenophthalic acid or anhydride, benzenesulfonic acid, p-toluenesulfonic acid; benzene Use of arylsulfinic acids such as sulfinic acid and p-toluenesulfinic acid or salts thereof; lithium salts of higher fatty acids such as lithium myristate, lithium stearate, lithium behenate, lithium palmitate and lithium laurate as acid stabilizers. be able to.

Other acid stabilizers include salicylic acid, p-
Alkyl-substituted benzoic acids such as hydroxybenzoic acid, tetrabromobenzoic acid, tetrachlorobenzoic acid, p-acetamidobenzoic acid, pt-butylbenzoic acid, phthalic acid, isophthalic acid, trimellitic acid, pyromellitic acid, dicitric acid, 5 '5'-Methylenebissalicylic acid, citric acid, tartaric acid, oxalic acid, boric acid, phosphoric acid, pyrophosphoric acid and the like are also effective. These acid stabilizers not only prevent thermal fogging, but also have the effect of preventing background discoloration upon exposure to white light after image formation and improving shelf life.

Other compounds effective for preventing heat fogging and preventing photodiscoloration include benzotriazole and its derivatives, tetrazole and its derivatives, thiouracils,
Compounds such as -phenyl-5-mercaptotetrazole, azole thioethers or blocked azolethiones disclosed in JP-A-47-318, tetrazolylthio compounds disclosed in U.S. Pat. No. 3,700,457; 3,707,377 and 4,
No. 108,455, photosensitive halogeno organic oxidizing agents; polybrominated organic compounds such as 2,4-bis (tribromomethyl) -s-triazine and polybromoalkylsulfonyl compounds shown in 3,874,946. compounds, the 4,546,075 trihalomethyl tetrazole derivatives as shown in JP, trihalomethyl benzimidazole and benzoxazole counterparts, or benzothiazole counterparts, R ^a -CX disclosed in JP-a-59-57234 A compound represented by _2- ^Rb (X represents halogen: ^Ra , ^Rb represents a group such as acyl, oxycarbonyl, oxysulfonyl, alkylsulfonyl, allylsulfonyl, aralkylsulfonyl, carboxyl, sulfo, sulfamoyl, etc.), US Patent No. 4,465,761
No. 4,452,88.
2-trihalomethyl oxazole derivative shown in No. 5, a heterocyclic compound having a trihalomethyl group shown in 4,756,999, and a compound represented by the following formula disclosed in European Patent No. 622,666. Is valid.

[0085]

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In the above formula, R ⁵ , R ⁶ and R ⁷ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a thioalkyl group, a perhalogenated alkyl group,
Or a cycloalkyl group.

The effect of the present invention is particularly remarkable when the above-mentioned heat fogging photodiscoloration inhibitor is used in combination with a thermoresponsive capsule.

In the recording material of the present invention, as a binder for each layer of the recording material such as a protective layer, a light and heat sensitive recording layer, and an intermediate layer, emulsification and dispersion of a photocurable composition and encapsulation of an organic silver salt or a developer thereof. Polystyrene, polyvinyl formal, polyvinyl butyral, acrylic resin: polymethyl acrylate, polybutyl acrylate, polymethyl methacrylate, polybutyl methacrylate and copolymers thereof, phenolic resin, styrene -Solvent-soluble polymers such as butadiene resin, ethylcellulose, epoxy resin, urethane resin and the like, or polymer latexes thereof can also be used. Among these, gelatin and polyvinyl alcohol are preferred.

In each layer of the light and heat sensitive recording material of the present invention, various surfactants may be used for various purposes such as a coating aid, antistatic, improvement of slipperiness, emulsification dispersion, and prevention of adhesion. Examples of the surfactant include nonionic surfactants such as saponin, polyethylene oxide, polyethylene oxide derivatives such as alkyl ether of polyethylene oxide, alkyl sulfonates, alkyl benzene sulfonates, alkyl naphthalene sulfonates, alkyl sulfates, N -Anionic surfactants such as -acyl-N-alkyltaurines, sulfosuccinates, sulfoalkylpolyoxyethylenalkylphenyl ethers, amphoteric surfactants such as alkylbetaines and alkylsulfobetaines, aliphatic or Cationic surfactants such as aromatic quaternary ammonium salts can be used as needed.

Various additives can be added to the recording material of the present invention, if necessary, including the additives described above. For example, typical examples of dyes, ultraviolet absorbers, plasticizers, optical brighteners, matting agents, coating aids, curing agents, antistatic agents and slipperiness improvers for preventing irradiation and halation are Research Disclosure,
Vol. 176, December 1978, Item 176
43, and Vol. 187, November 1979, I
tem 18716.

The support used in the present invention may be transparent or opaque. Opaque supports include paper,
Examples thereof include synthetic paper, paper obtained by laminating a polymer film on paper, aluminum vapor-deposited base, and polymer film coated with a white pigment. In this case, it is preferable to use a support having high reflectivity of laser light so that the laser light is irradiated from the recording layer side and is efficiently absorbed by the recording layer.

On the other hand, as the transparent support, it is preferable to use a support that does not absorb the laser beam to be irradiated and has dimensional stability that does not deform due to heat generated by the laser beam irradiation. In this case, recording can be performed by irradiating a laser beam through the transparent support. The thickness of the support is 10 μm to 200 μm.

Examples of such a transparent support include polyester films such as polyethylene terephthalate, polyethylene naphthalate and polybutylene terephthalate, cellulose derivative films such as cellulose triacetate film, and polyolefins such as polystyrene film, polypropylene film and polyethylene film. Examples thereof include a film, a polyimide film, a polyvinyl chloride film, a polyvinylidene chloride film, a polyacrylic acid copolymer film, and a polycarbonate film. These can be used alone or in combination. Films that can be used as the transparent support preferably have a haze (degree of cloudiness) of 3% or less.

As the support used in the present invention, a polyester film which has been subjected to heat treatment and antistatic treatment is particularly preferred.

The method for producing the film is not particularly limited as long as the above object can be achieved. Specific examples include a method of producing a film by heating and melting, extruding, cooling, solidifying, stretching, and heat setting.

Further, inorganic fine particles, an antioxidant, an antistatic agent, a dye and the like can be added to the support as long as the object of the present invention is not hindered.

The inorganic fine particles that can be used here include I
Group A, IIA, IVA, VIA, VIIA, VIII, I
Group B, IIB, IIIB, IVB, oxides, hydroxides, sulfides, nitrides, halides, carbonates, acetates, phosphates, phosphites, organic carboxylate of each element, Silicates,
Examples include titanates, borates and their hydrated compounds, composite compounds centered on them, and natural mineral particles.
Specifically, Group IA element compounds such as lithium fluoride, borax (sodium borate hydrate), magnesium carbonate, magnesium phosphate, magnesium oxide (magnesia), magnesium chloride, magnesium acetate, magnesium fluoride, magnesium titanate, silicate Magnesium, magnesium silicate hydrate (talc), calcium carbonate, calcium phosphate, calcium phosphite, calcium sulfate (gypsum), calcium acetate, calcium terephthalate, calcium hydroxide, calcium silicate, calcium fluoride, calcium titanate, titanic acid Group IIA element compounds such as strontium, barium carbonate, barium phosphate, barium sulfate and barium phosphite, titanium dioxide (titania), titanium monoxide, titanium nitride, zirconium dioxide (zirconia), and zirconium oxide IVA Group element compound, molybdenum dioxide,
Group VIA element compounds such as molybdenum trioxide, molybdenum sulfide, manganese chloride, manganese acetate and the like; Group VIII element compounds such as cobalt chloride and cobalt acetate; Group IB element compounds such as cuprous iodide; Group IIB element compounds such as zinc oxide and zinc acetate; aluminum oxide (alumina); aluminum oxide; aluminum fluoride; group IIIB element compounds such as aluminosilicate (alumina silicate, kaolin, kaolinite); silicon oxide (silica, silica gel) ), Graphite, carbon, graphite, glass etc.
Particles of a group IVB element compound, natural minerals such as kernalite, kainite, mica (mica, kinmo), and virose ore. Above all, from the viewpoint of handleability,
Preferred are silica, talc, titania, alumina, calcium carbonate, calcium oxide, calcium chloride and the like, and mixtures thereof. Examples of the organic fine particles include fine particles such as cross-linked polystyrene and cross-linked polymethyl methacrylate. Antioxidants, antistatic agents, dyes, and the like can be blended with known additives for resins according to the purpose.

[0098] Further, the rear surface of polyoxyethylene-based support, sulfonic acid-based surfactant, and / or volume resistivity of 10 ⁰ ~10 ⁵ Ω · cm of ZnO, TiO _2, SnO
₂ , Al ₂ O ₃ , In ₂ O ₃ , SiO ₂ , MgO, Ba
A back layer containing at least one kind of crystalline metal oxide selected from O and MoO ₃ or fine particles of these composite oxides can be provided. These components can also be contained in a suitable binder to form a back layer. The support on which such a back layer is formed has an antistatic ability with excellent practical various performances.

In the present invention, when a polymer film or paper laminated with the polymer film is used as a support, or when a transparent support is used, in order to enhance the adhesiveness between the support and the recording layer, these are used. It is preferable to provide an undercoat layer between the layers.

As the material for the undercoat layer, gelatin, synthetic polymer latex, nitrocellulose, acrylate copolymer, polyvinylidene chloride, styrene / butadiene rubber, aqueous polyester and the like are used. The coating amount of the undercoat layer is preferably in the range of ^{0.1g / m 2 ~2.0g / m 2} , preferably in the range particularly ^{0.2g / m 2 ~1.0g / m 2} .

The undercoat layer is swelled by water contained in the recording layer when the recording layer is coated thereon, and may deteriorate the image quality of the recording layer. Therefore, the undercoat layer is cured with a hardener. It is desirable.

As the hardener, for example, JP-A-2-141
No. 279 can be mentioned. The addition amount of these hardeners is in the range of 0.20% by weight to 3.0% by weight based on the weight of the undercoat layer, and an appropriate addition amount is selected according to the coating method and the desired degree of curing. be able to.

Depending on the hardener used, if necessary, caustic soda may be further added to adjust the pH of the solution to an alkaline side, or the pH of the solution may be adjusted to an acidic side by citric acid or the like. Further, an antifoaming agent may be added to eliminate bubbles generated at the time of application, or an activator may be added to improve the leveling of the liquid and prevent the generation of coating streaks.

Further, before applying the undercoat layer, it is desirable to activate the surface of the support by a known method. As the method of the activation treatment, an etching treatment with an acid, a flame treatment with a gas burner, a corona discharge treatment, a glow discharge treatment, or the like is used. From the viewpoint of cost or simplicity, US Pat. No. 075,
Nos. 2,846,727 and 3,549,406
No. 3,590,107 and the like are most preferably used.

In the present invention, it is preferable to provide a protective layer containing a pigment on the recording layer in order to protect the recording layer from sticking, solvent and the like.

Examples of such pigments include mica, talc,
Calcium carbonate, zinc oxide, titanium oxide, aluminum hydroxide, kaolin, talc, fluorite, synthetic silicate, amorphous silica, urea formalin resin powder and the like,
Among these, calcium carbonate, aluminum hydroxide, kaolin, silica, mica and talc are particularly preferred.

The protective layer in the present invention may contain aged polyvinyl alcohol, carboxy-modified polyvinyl alcohol, silica-modified polyvinyl alcohol, etc. as a binder from the viewpoint of retaining the pigment and improving the transparency. preferable.

The coating solution for a protective layer (referred to as a protective layer solution) in the present invention is obtained by mixing a pigment with the above-mentioned binder solution. Depending on the purpose, zinc stearate, calcium stearate, paraffin wax, polyethylene wax may be used. And various auxiliaries such as a fluorescent brightener, a crosslinking agent, a sulfosuccinic acid-based alkali metal salt and a fluorine-containing surfactant, and a polyoxyethylene surfactant.

The photosensitive and heat-sensitive coating solution of the recording material of the present invention and the coating solution for each of the above-mentioned layers may be dissolved in a solvent, if necessary, coated on a desired support, and dried to obtain the coating material of the present invention. A recording material is obtained. Examples of the solvent used in this case include water and alcohol: for example, methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, methyl cellosolve, 1-methoxy-2-propanol; a halogen-based solvent; Chloride, ethylene chloride: ketone: for example, acetone, cyclohexanone, methyl ethyl ketone: ester: For example, a single substance such as methyl acetate cellosolve, ethyl acetate, methyl acetate: toluene, xylene and the like, and a mixture of two or more thereof are exemplified. Of these, water is particularly preferred.

To apply the coating solution for each layer onto the support, a blade coater, a rod coater, a knife coater, a roll doctor coater, a reverse roll coater, a transfer roll coater, a gravure coater, a kiss roll coater, a curtain coater, an extender A lution coater or the like can be used. As the coating method, Rcscan Disclosurc, V
ol. 200, December 1980, Item 2003
Section 6 XV can be referred to.

The coating liquid layers of the recording material of the present invention include:
2.5 to 25 g / m ^{2 in} solid weight after coating and drying
It is preferable to provide a recording layer having a thickness of 0.2 to 7 g / m ² in terms of solid content.

The coating amount of the organic silver salt and the developer is preferably 0.5 to 3.0 g / m ² , more preferably 0.8 to 2.0 g / m ² , as the Ag component in the recording layer. Is preferred. The thickness of the recording layer is 1 to 20 μm (0.1 μm).
m to 50 μm).

The laser beam used in the present invention has a wavelength in the near infrared region. Specific examples thereof include a helium-neon laser, an argon laser, a carbon dioxide laser, a YAG laser, and a semiconductor laser.

After the imagewise exposure, the recording material of the present invention is subjected to a heat development treatment in which the entire recording material is heated. Various conventionally known methods can be used as a heating method in the heat development processing. The heating temperature is generally between 80 ° C and 200 ° C, preferably between 85 ° C and 130 ° C.
The heating time is 1 second to 5 minutes, preferably 3 seconds to 1 minute. It is preferable that the entire surface of the recording material of the present invention is exposed after the heat development treatment, and the uncured portion is also light-cured. Since the entire surface exposure suppresses the coloring reaction of the background portion and the discoloration reaction of the coloring portion, the storability of the image is improved. Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

[0115]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples. Unless otherwise specified in the text, "%" is "% by weight"
And “parts” means “parts by weight”.

(Example 1) Preparation of silver behenate 25.59 g of behenic acid was added to 480 g of water and heated to 90 ° C, and then an aqueous solution in which 3.0 g of NaOH was dissolved in 45 g of water was added and stirred well. Then, it cooled to 50 degreeC.

Next, Ag was added to 75 g of water.
After an aqueous solution to which 12.9 g of NO ₃ had been added was added dropwise over 5 minutes, stirring was continued for 30 minutes to cause a reaction.

The obtained reaction solution was filtered with a filter cloth, and water 800
After adding ml, stirring and washing, the mixture was filtered again. After such a washing operation was repeated three times, the obtained solid content was reduced to 5%.
It was dried for 3 days by a blow dryer at 0 ° C. to obtain a dried solid of silver behenate.

Preparation of Capsule Solution Enclosing Silver Behenate 27 g of dried silver behenate solid was weighed, and 1.10 g of polyvinyl butyral and 110 g of isoamyl acetate were weighed.
And dispersed in a paint shaker for 3 hours, and further dispersed in a motor mill to obtain an average particle diameter of 0.4 μm.
A silver behenate dispersion was obtained.

10 g of the obtained dispersion was used as a capsule wall material for mylionate MR-200 (trade name, manufactured by Takeda Pharmaceutical Co., Ltd.):
Isocyanate compound having the structure of the formula (j))
The oil phase component was added with 2.5 g of Takenate D-110N (trade name, manufactured by Takeda Pharmaceutical Co., Ltd .: isocyanate compound having the structure of the formula (a)). This was added to 10% polyvinyl alcohol (trade name: PVA21)
7E, manufactured by Kuraray Co., Ltd.) and added to a solution (aqueous phase) in which 16 g of an aqueous solution and 40 g of water were mixed, and 8,000 rpm using a homogenizer (Ace Homogenizer manufactured by Nippon Seiki).
m for 10 minutes.

The obtained fine emulsified dispersion was heated to 40 ° C. with stirring, and kept for 3 hours to carry out an encapsulation reaction. The obtained liquid is a microcapsule liquid containing silver behenate and having an average particle size of 0.8 μm.

Preparation of Developer Dispersion Solution To 53 g of a 15% aqueous polyvinyl alcohol solution (PVA205, hereinafter the same as described above), 24 g of a developer represented by the following formula and 103 g of ion-exchanged water were added, and the mixture was dispersed for 3 hours with a paint shaker to obtain an average particle size. A 0.6 μm developer dispersion was prepared.

[0123]

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Preparation of 4-Methylphthalic Acid Dispersion A 15% aqueous solution of polyvinyl alcohol (PVA205) 3
To 3 g, 20 g of 4-methylphthalic acid and 67 of ion-exchanged water
g, and dispersed for 3 hours with a paint shaker to prepare a dispersion having an average particle size of 0.6 μm.

Preparation of emulsion of photocurable composition 0.13 g of photopolymerization initiator (1) and spectral sensitizing dye (1)
0.1 g and isopropyl acetate (solubility in water about 4.3
%) Of a mixed solution of 3 g was added with 5 g of a polymerizable vinyl monomer plasticizer (1). This solution was added to a mixed solution of 13 g of a 13% aqueous solution of polyvinyl alcohol (PVA205), 0.8 g of a 2% aqueous solution of surfactant (1) and 0.8 g of a 2% aqueous solution of surfactant (2), and a homogenizer (Japan) The mixture was emulsified at 10,000 rpm for 5 minutes by using Seiki Co., Ltd. to obtain an emulsion of the photocurable composition.

[0126]

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Preparation of Coating Solution for Protective Layer 32 g of water and 10% of carboxy-modified polyvinyl alcohol (trade name: PVA-KL-318, manufactured by Kuraray Co., Ltd.)
32 g of an aqueous solution of an epoxy-modified polyamide (trade name:
FL-71, manufactured by Toho Chemical Co., Ltd.) and 8 g of a 30% dispersion, mixed with polyoxyethylene (surfactant) 2
5 g of a 20% aqueous solution and 4 g of a dispersion of 20% zinc stearate (trade name: Hydrin Z, manufactured by Chukyo Yushi Co., Ltd.) were added to obtain a coating solution for a protective layer.

Preparation of Coating Solution 93 g of the silver behenate-encapsulated capsule solution, 3.8 g of the developer dispersion, 0.28 of the 4-methylphthalic acid dispersion
g, 10 g of an emulsion of the photocurable composition, 5% carboxybenzotriazole methyl ester in methanol 4
g, and 0.34 g of a 50% aqueous solution of phthalazine were added to prepare a recording layer coating solution (1).

Preparation of photosensitive and heat-sensitive recording material The above coating solution for recording layer (1) was placed on a transparent polyethylene terephthalate support (thickness: 130 μm) provided with an undercoat layer.
Using a wire bar, the dry weight of the coating layer is 23 g / m
² and dried at 30 ° C. for 10 minutes. The protective layer coating solution was applied thereon using a wire bar so that the dry weight of the applied layer was 2.0 g / m ² ,
After drying at 0 ° C. for 10 minutes, a light and heat sensitive recording material sample of Example 1 was obtained.

Example 2 Preparation of Silver Behenate Dispersion A 14 g portion of the prepared silver behenate dry solid was weighed, and carboxybenzotriazole methyl ester 1.0 g was added thereto.
6 g, 0.282 g of a dye represented by the following formula, 35 g of a 15% aqueous solution of polyvinyl alcohol (trade name: PVA205; manufactured by Kuraray Co., Ltd.) and 68 g of ion-exchanged water were added, and dispersed for 3 hours using a paint shaker. A silver behenate dispersion having a particle size of 0.6 μm was obtained.

[0131]

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Preparation of Capsule Solution Enclosing Developer 5 g of developer, 15 g of ethyl acetate, g of diisopropylnaphthalene, and millionate MR-2 as a capsule wall material
00 (trade name, manufactured by Takeda Pharmaceutical Co., Ltd .: isocyanate compound having a structure of the formula (j)) 4 g, Takenate D-11
An oil phase component was prepared by adding 7 g of 0N (trade name, manufactured by Takeda Pharmaceutical Co., Ltd .: isocyanate compound having the structure of the formula (a)). This was prepared using 10% polyvinyl alcohol (trade name: PVA217E, Kuraray Co., Ltd.)
A solution (aqueous phase) obtained by mixing 60 g of an aqueous solution and 20 g of water
And finely emulsified for further 10 minutes at 8,000 rpm using a homogenizer (Ace Homogenizer, manufactured by Nippon Seiki Co., Ltd.).

The obtained fine emulsified dispersion was heated to 40 ° C. with stirring and kept for 3 hours to carry out an encapsulation reaction. The resulting liquid has an average particle size that contains the developer.
μm microcapsule solution.

Preparation of Coating Solution In addition to 21.7 g of the above-mentioned silver behenate dispersion and 11.3 g of the above-mentioned developer-containing capsule solution, the same 4 as used in Example 1 was used.
-0.28 g of methylphthalic acid dispersion, 10 g of an emulsion of the photocurable composition, 4 g of a 5% carboxybenzotriazole methyl ester methanol solution, and 0.34 g of a 50% aqueous solution of phthalazine were added to prepare a recording layer coating solution (2). .

Preparation of photosensitive and heat-sensitive recording material The recording layer coating solution (2) was placed on a transparent polyethylene terephthalate support (thickness: 130 μm) provided with an undercoat layer.
Using a wire bar, the dry weight of the coating layer is 17 g / m.
² and dried at 30 ° C. for 10 minutes. The protective layer coating solution was applied thereon using a wire bar so that the dry weight of the applied layer was 2.0 g / m ² ,
After drying at 0 ° C. for 10 minutes, a light and heat sensitive recording material sample of Example 2 was obtained. (Comparative Example 1) A recording layer coating liquid (3) was prepared in the same manner as in Example 1 except that 21.7 g of a silver behenate dispersion liquid was added instead of 93 g of the silver behenate-encapsulated capsule liquid. did.

Preparation of photosensitive and heat-sensitive recording material The above-mentioned coating solution for recording layer (3) was placed on a transparent polyethylene terephthalate support (thickness: 130 μm) provided with an undercoat layer.
Using a wire bar, the dry weight of the coating layer is 14 g / m
² and dried at 30 ° C. for 10 minutes. The protective layer coating solution was applied thereon using a wire bar so that the dry weight of the applied layer was 2.0 g / m ² ,
After drying at 0 ° C. for 10 minutes, a light and heat sensitive recording material sample of Comparative Example 1 was obtained.

Recording and Evaluation of Image Each of the obtained photosensitive, heat-sensitive and heat-sensitive recording materials was irradiated with a semiconductor laser beam (GaAs junction laser) having a wavelength of 780 nm from the heat-sensitive layer side in a step wedge-like irradiation energy while changing the scanning speed. Change up to 1 on the surface of heat-sensitive layer
Irradiation was performed so as to have an energy of ² mJ / mm ² , and then the mixture was uniformly heated at 120 ° C. for 15 seconds.

The color transmission density of the image thus formed was measured by a Macbeth reflection densitometer. The sensitivity is
The evaluation was made based on the energy at which the background appeared in the wedge image at a constant exposure. Table 1 shows the results.

[0139]

[Table 1]

As is clear from Table 1, it was found that all of the photosensitive and heat-sensitive recording materials of the present invention had high sensitivity and the color density of recorded images was sufficient. On the other hand, in Comparative Example 1 in which both silver behenate and the developer were present in a dispersed state, no positive image was formed.

[0141]

According to the photosensitive and heat-sensitive recording material of the present invention, recording can be performed by using an infrared laser beam, and there is no need to use a developer or the like, and no unnecessary waste is generated. And a positive image with high contrast and high contrast can be obtained. Further, according to the image forming method of the present invention using the photosensitive and heat-sensitive recording material, it is possible to form a positive or negative black-and-white or color high-contrast image.

Claims (11)

[Claims] 1. A light- and heat-sensitive recording material comprising a support and a light- and heat-sensitive recording layer provided on a support, wherein the light- and heat-sensitive recording layer comprises an organic silver salt encapsulated in heat-responsive microcapsules, and a heat-sensitive microcapsule. A light- and heat-sensitive recording material, comprising: a reducing agent for an organic silver salt dispersed outside; and a composition that plasticizes the thermoresponsive microcapsules and is curable by light irradiation. 2. A light- and heat-sensitive recording material having a light- and heat-sensitive recording layer provided on a support, wherein the light- and heat-sensitive recording layer comprises a reducing agent for an organic silver salt encapsulated in heat-responsive microcapsules. A light and heat sensitive recording material, comprising: an organic silver salt dispersed outside a microcapsule; and a composition that plasticizes the thermoresponsive microcapsule and can be cured by light irradiation. 3. The composition which plasticizes the thermoresponsive microcapsules and cures by irradiation with light contains a photopolymerization initiator and a polymerizable monomer having a plasticizing ability. Or the light and heat sensitive recording material according to 2. 4. The light and heat sensitive recording material according to claim 3, wherein the photopolymerization initiator is an organic borate salt compound. 5. A light and heat sensitive recording material, wherein the organic borate salt compound is a compound represented by the following general formula (1). Embedded image Wherein M is an alkali metal atom, a quaternary ammonium,
Cu, Ag, Hg, Pd, Fe, Co, Sn, Mo, C
a cation selected from r, Ni, As, Se, n is an integer of 1 to 6, R ¹ , R ² , R ³ and R ⁴ are each a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkyl group; Substituted alkenyl group, substituted or unsubstituted alkynyl group, alicyclic group, substituted or unsubstituted aryl group, substituted or unsubstituted alkaryl group, substituted or unsubstituted aryloxyl group, substituted or unsubstituted aralkyl group,
Represents a substituted or unsubstituted heterocyclic group or a substituted or unsubstituted silyl group. Here, R ¹ , R ² , R ³ and R ⁴ may be the same or different from each other, and two or more of these groups may be bonded to form a cyclic structure. 6. The light and heat sensitive recording material according to claim 3, wherein the polymerizable monomer having a plasticizing ability is a polymerizable vinyl monomer containing a phenol group. 7. The light- and heat-sensitive recording material according to claim 3, wherein the composition that plasticizes the thermoresponsive microcapsules and cures by irradiation with light further contains a spectral sensitizing dye. . 8. The light and heat sensitive recording material according to claim 7, wherein the spectral sensitizing dye is an infrared absorbing dye. 9. An organic silver salt encapsulated in a thermoresponsive microcapsule on a support, a reducing agent for an organic silver salt dispersed outside the thermoresponsive microcapsule, and plasticizing the thermoresponsive microcapsule. A photosensitive heat-sensitive recording material provided with a light-sensitive heat-sensitive recording layer containing a composition curable by light irradiation is exposed imagewise by exposure means, and then the entire surface of the exposed light-sensitive heat-sensitive recording material is heated. An image forming method, wherein a positive image is formed by heating uniformly by means. 10. A reducing agent for an organic silver salt encapsulated in a thermoresponsive microcapsule on a support, an organic silver salt dispersed outside the thermoresponsive microcapsule, and plasticizing the thermoresponsive microcapsule. A photosensitive heat-sensitive recording material provided with a light-sensitive heat-sensitive recording layer containing a composition curable by light irradiation is exposed imagewise by exposure means, and then the entire surface of the exposed light-sensitive heat-sensitive recording material is heated. An image forming method, wherein a positive image is formed by heating uniformly by means. . 11. An image forming method according to claim 9, wherein said exposure means is an infrared laser beam.