JPH10239794A - Color-developing image forming material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color-developing image forming material to be allowed to develop color by exposure or heating without using a leuco dye and superior in film strength, by incorporating a specified compound and forming a dye skeleton by an acid generated by light or heat. SOLUTION: This color-developing image forming material contains (A) the compound to be allowed to generate an acid by light or heat (acid generator), (B) an aromatic hydrocarbon or heterocyclic compound substituted by a functional group incorporating a hetero atom, and (C) a carbonyl compound or the like. The acid generator (A) is decomposed by irradiation with light or heating to >=100 deg.C and generates and acid and it is embodied by iodonium salts sulfonium salts and the like. The compound (B) and the compound (C) reacts with each other in the presence of an acid generated from (A) to form the dye skeleton, preferably, triphenylmethane type, merocyanine type, and porphyrin type dyes and the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a thermal paper, a proof,
The present invention relates to a novel color image forming material that can be used for dry lith films, color filters, lithographic printing plates, and the like.

[0002]

2. Description of the Related Art Materials which form a colored image by exposure or heating are well known in the art. For example, a proof used in the printing industry and a color filter used in display manufacturing use a photosensitive recording material containing a pigment. In these photosensitive recording materials, a colored image is obtained by curing an image by exposure and then removing an unexposed portion with alkaline water or the like. At this time, the image portion is formed by curing the colored portion of the pigment originally contained, and does not mean that a new dye is formed in the exposed portion.

Further, the lithographic printing plate material includes a material capable of obtaining a printed image by exposure. The material used is a combination of a dye and a photoacid generator, and utilizes a color fading reaction of a dye due to an acid generated by exposure. Therefore, it is a decolorable image forming material, and no new dye is formed at the exposed portion.

Further, a dry lith film, which has been used in the printing industry in recent years, is disclosed in US Pat. No. 5,491,045. Ablated by an infrared laser to obtain a colored image. The dye is decomposed or sublimated by the laser, and, of course, no new dye is formed at the laser irradiation part.

On the other hand, as a color-forming type image forming material, there is a thermal recording material used for thermal paper. This recording material uses a leuco dye, a developer, and microcapsules, and the microcapsules are disintegrated or melted by heating with a thermal head or the like, and the leuco dye and the developer react to obtain a color-formed image. Therefore, a new dye skeleton was not formed in the heating section. Further, in this heat-sensitive recording material, since a leuco dye is used, there is a problem that the recording material is colored when stored for a long period of time. further,
There is a problem that the film strength of an image formed after thermal printing is weak.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a novel color image forming material which does not use a leuco dye. Another object of the present invention is to provide a color image forming material which is excellent in film strength of an image formed by exposure or heating.

[0007]

Means for Solving the Problems The present inventor paid attention to the components of a color image forming material, and as a result of diligent studies, was able to achieve the above object by a completely new method of using a compound that forms a dye skeleton. And completed the present invention. That is, the present invention provides (A) a compound that generates an acid by light or heat (hereinafter, referred to as an acid generator);
(B) an aromatic hydrocarbon compound or a heterocyclic compound substituted with a functional group containing a hetero atom in the molecule, and (C) a compound selected from a carbonyl compound and an equivalent thereof, which is generated by light or heat. (B) and (C) cause a reaction to form a dye skeleton by an acid.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. [(A) Acid Generator] In the present invention, the acid generator refers to a compound which is decomposed by light irradiation or heating at 100 ° C. or more to generate an acid. The acid generated here is preferably a strong acid having a pKa of 2 or less, such as sulfonic acid and hydrochloric acid, from the viewpoint of the effect. Examples of the acid generator suitably used in the present invention include onium salts such as iodonium salts, sulfonium salts, phosphonium salts and diazonium salts. Specifically, US Pat.
-20629. Particularly, an iodonium salt, a sulfonium salt, and a diazonium salt having a sulfonate ion as a counter ion are preferable. As diazonium salts, US Pat.
7, the diazonium compound described in US Pat.
03 diazonium compound and JP-A-1-1
Also preferred are diazo resins described in JP-A No. 02456 and JP-A-1-102457. US5
Benzyl sulfonates described in 135,838 and US 5,200,544 are also preferred. Further, active sulfonic acid esters and disulfonyl compounds described in JP-A Nos. 2-100054, 2-100055 and 8-9444 are also preferable. Other,
Also preferred are haloalkyl-substituted S-triazines described in JP-A-7-271029.

These compounds are used in an amount of 0.01 to 50% by weight, preferably 0.1 to 25% by weight based on the total solid content of the image recording material.
% By weight, more preferably 0.5 to 15% by weight, is added to the color image forming material. If the amount is less than 0.01% by weight, no color image is formed. When the amount exceeds 50% by weight, the film strength of the color image becomes weak. These compounds may be used alone or
A combination of more than one species may be used.

[(B) Aromatic hydrocarbon compound or heterocyclic compound substituted with a functional group containing a hetero atom in the molecule] In the present invention, the dye skeleton formed in the presence of an acid catalyst preferably contains Phenylmethane dyes,
Diphenylmethane dyes, cyanine dyes, merocyanine dyes, phthalocyanine dyes, porphyrin dyes, and the like. In the present invention, the compound is selected from (B) an aromatic hydrocarbon compound or a heterocyclic compound substituted with a functional group containing a hetero atom in the molecule, and (C) a carbonyl compound and an equivalent thereof described below. The compound reacts with the compound in the presence of an acid generated from the acid generator (A) to form a dye skeleton as described above.

The compound (B) is an aromatic hydrocarbon compound or a heterocyclic compound substituted with a functional group containing a hetero atom such as a nitrogen atom, an oxygen atom or a sulfur atom. It is preferable to use an aromatic hydrocarbon compound substituted with a functional group containing a nitrogen atom, or a heterocyclic compound containing any one of a nitrogen atom, an oxygen atom and a sulfur atom.

The aromatic hydrocarbon compound substituted with a functional group containing a nitrogen atom is preferably an amino group-substituted aromatic hydrocarbon compound. Specifically, alkylamino substitution such as aniline, naphthylamine, anthracenylamine, monomethylaniline, dimethylaniline, diethylaniline, N-methyl-N-hydroxyethylaniline, N, N-dihydroxyethylaniline, N-phenylmorpholine, etc. Aromatic hydrocarbon compounds, arylamino-substituted aromatic hydrocarbon compounds such as diphenylamine and triphenylamine, and alkylarylamino-substituted aromatic hydrocarbon compounds such as N-methyldiphenylamine. Further, N, N,
Aromatic hydrocarbon compounds having two or more amino groups such as N ′, N′-tetramethylphenylenediamine, N,
Aromatic hydrocarbon compounds having other substituents such as N-dimethylaminophenol and N, N-dimethylaminothioanisole, N, N-dimethylaminohalogenobenzene are also preferred.

As the heterocyclic compound containing any one of a nitrogen atom, an oxygen atom and a sulfur atom, a heterocyclic ring having at least one double bond conjugated to these hetero atoms is preferable. Specifically, pyrrole, furan, thiophene,
Monocyclic heterocycles such as oxazole, isoxazole, thiazole, isothiazole, imidazole, pyrazole, furazane, oxadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, etc., and indole, isoindole, benzofuran, benzothiophene, indolizine , Quinoline, isoquinoline, pudding,
Indazole, benzimidazole, benzothiazole, benzoxazole, quinazoline, cinnoline, quinoxaline, phthalazine, pteridine, carbazole,
Examples include fused heterocycles such as acridine, phenanthridine, xanthene, phenazine, and phenothiazine. These heterocyclic compounds may have a substituent. Preferred substituents include a hydrocarbon group having 20 or less carbon atoms, an alkoxy group having 20 or less carbon atoms, an aryloxy group having 20 or less carbon atoms, and a halogen atom. Of these heterocyclic compounds, those containing a nitrogen atom are particularly preferred because of their high density when they develop color.

The heterocyclic compound preferably used in the present invention is a 5-membered ring having two conjugated double bonds, or a 3-membered ring.
6-membered ring having two conjugated double bonds, and a heterocyclic compound in which these heterocycles are condensed. Further, a heterocyclic ring in which an aromatic hydrocarbon ring such as a benzene ring or a naphthalene ring is condensed with these heterocyclic rings is also preferable. Since these heterocycles have aromaticity, they are called aromatic heterocycles.

As the compound (B), a low molecular weight compound may be used as it is. However, when a color image is formed, a cross-linking curing reaction occurs simultaneously, and as a result, the film strength of the color image becomes high. It is preferable to use it by introducing it. The compound group (B) may be introduced into the polymer as a component constituting the main chain of the polymer, but is pendantly bonded to the side chain of the polymer because the film strength of the image is high. Is more preferred. in this case,
The compound (B) may be directly bonded to the polymer main chain, but also because the film strength of the image area is high.
It is preferable that they are pendantly linked via an appropriate linking chain. Preferred linking chains include, for example, an ester bond, a carboxylic acid amide bond, a sulfonic acid amide bond,
Examples thereof include an ether bond, a thioether bond, and a hydrocarbon group having 20 or less carbon atoms which may contain these bonds. Examples of the polymer main chain include vinyl polymers, polyesters, and polyurethanes, which are main chains such as poly (meth) acrylate, polystyrene, and polyvinyl acetal. Is preferred.

The polymer having the compound (B) in the side chain suitably used in the present invention includes a polymer having a structure represented by the general formula (I).

Formula (I)

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In the general formula (I), R ₁ represents a hydrogen atom or a methyl group. L ₁ represents a single bond, an ester bond, a carboxylic acid amide bond, a sulfonic acid amide bond, an ether bond, a thioether bond, an amino bond, or a hydrocarbon group having 20 or less carbon atoms which may contain these bonds. A ₁ represents an aromatic hydrocarbon compound or a heterocyclic compound substituted with a functional group containing a nitrogen atom, an oxygen atom or a sulfur atom. However, when an ether bond, a thioether bond or an amino bond is directly bonded to A ₁ in L ₁ , the hetero atom may not be contained in A ₁ .

The polymer having a structure represented by the general formula (I) can be obtained by radical polymerization using a corresponding monomer represented by the general formula (II) by a conventionally known method. In the general formula (II), the same reference numerals as those in the general formula (I) denote the same parts, and a description thereof will be omitted.

Formula (II)

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Among the polymers having the structure represented by the general formula (II), those particularly preferably used in the present invention are those having the structure represented by the following general formula (III) or (IV). .

Formula (III)

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Formula (IV)

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In the general formulas (III) and (IV), R₁Is water
Shows an atom or a methyl group. L_TwoIs a single bond,
Bond, carboxylic acid amide bond, sulfonic acid amide bond
Bond, ether bond, thioether bond, amino bond or
Has 20 or less carbon atoms which may contain these bonds
Shows a hydrocarbon group. X1 is a nitrogen atom, an oxygen atom or
Indicates a sulfur atom. X_TwoIs NR_Three, Oxygen atom or sulfur
Indicates a yellow atom. X₁And X _TwoOne of which is a nitrogen atom
Preferably, there is. R_TwoAnd and R_ThreeIs the same
May have a hydrogen atom or a substituent,
Represents a hydrocarbon group having 20 or less carbon atoms. Substituent and
A halogen atom, a hydroxy group, a cyano group, a nitro
B, carboxyl, carbamoyl, carbon number 10
The following alkoxy group or aryl having 10 or less carbon atoms
A ruoxy group is preferred. n₁And n_TwoAre the same but different
And may be an integer of 0 to 4. Where n₁And n
_TwoDo not become 0 at the same time. A_TwoHas a substituent
Represents an aromatic hydrocarbon group having 20 or less carbon atoms which may be present.
You. Examples of the substituent include a halogen atom, a hydroxy group,
Ano group, nitro group, carboxyl group, carbamoyl group,
An alkoxy group having 10 or less carbon atoms, or 10 carbon atoms
The following aryloxy group, Perflu having 10 or less carbon atoms
Oroalkyl group, hydroxyalkyl having 10 or less carbon atoms
And a hydroxyaryl group having 10 or less carbon atoms is preferred.
New A_ThreeContains nitrogen, oxygen or sulfur atoms.
A heterocyclic group having 20 or less carbon atoms,
May be. Heterocyclic groups containing a nitrogen atom are particularly preferred.
As the substituent, a halogen atom, a hydroxy group, a cyano
Group, nitro group, carboxyl group, carbamoyl group, carbon
10 or less alkoxy groups or 10 or less carbon atoms
Aryloxy group, a perfluoro group having 10 or less carbon atoms
Alkyl group, hydroxyalkyl having 10 or less carbon atoms
Groups, hydroxyaryl groups having 10 or less carbon atoms are preferred
No.

The polymer having the structure represented by the general formula (III) or (IV) is prepared by subjecting the corresponding monomer represented by the general formula (V) or (VI) to radical polymerization by a conventionally known method. Is obtained by In general formulas (V) and (VI), the same reference numerals as those in general formulas (III) and (IV) denote the same components, and a description thereof will be omitted.

General formula (V)

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General formula (VI)

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In the present invention, examples of the monomer represented by the general formula (V) or (VI) which is preferably used are shown below. In the following formulas (V-1) to (VI-19), R ₁
Represents a hydrogen atom or a methyl group, and Y ₁ represents an oxygen atom or NH. N ₃ represents an integer of 1 to 20.

[0029]

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[0030]

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[0031]

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[0032]

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[0033]

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[0034]

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[0035]

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[0036]

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[0037]

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In the present invention, it is preferable to use a polymer obtained by radical polymerization of at least one of the monomers represented by the general formula (II).
Both homopolymers using only one of the monomers represented by I) and copolymers using two or more of them can be used.

In the present invention, it is preferable to use a copolymer with a conventionally known polymerizable monomer other than the monomer represented by the general formula (II). Examples of such other known monomers include, for example, acrylates such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, 2-hydroxyethyl acrylate, and benzyl acrylate; methyl methacrylate , Ethyl methacrylate, propyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, 2
Methacrylates such as -hydroxyethyl methacrylate and benzyl methacrylate; acrylonitrile, styrene, p-methoxystyrene and the like.

If necessary, a copolymer using a monomer having an acidic group may be used in order to improve the solubility in alkaline water. Examples of the monomer used include acrylic acid, methacrylic acid, itaconic acid, maleic acid, N- (2-carboxyethyl) acrylamide, N- (2-carboxyethyl) methacrylamide,
N- (carboxyphenyl) acrylamide, N- (carboxyphenyl) methacrylamide, carboxystyrene, maleimide, N- (phenylsulfonyl) acrylamide, N- (phenylsulfonyl) methacrylamide, N- (tolylsulfonyl) acrylamide, N-
(Tolylsulfonyl) methacrylamide, N- (chlorophenylsulfonyl) acrylamide, N- (chlorophenylsulfonyl) methacrylamide, N- (sulfamoylphenyl) acrylamide, N- (sulfamoylphenyl) methacrylamide, N- (methylsulfur) Famoylphenyl) acrylamide, N- (methylsulfamoylphenyl) methacrylamide, N- (phenylsulfamoylphenyl) acrylamide, N- (phenylsulfamoylphenyl) methacrylamide, N-
(Tolylsulfamoylphenyl) acrylamide, N
-(Tolylsulfamoylphenyl) methacrylamide, N-[(chlorophenylsulfamoyl) phenyl] acrylamide, N-[(chlorophenylsulfamoyl) phenyl] methacrylamide, N- (hydroxyphenyl) acrylamide, N- (hydroxy Phenyl) methacrylamide, N- (hydroxynaphthyl) acrylamide, N- (hydroxynaphthyl) methacrylamide and the like.

Further, although not an acidic group, sodium salts of p-styrenesulfonic acid, alkali metal salts of 2-acrylamido-2-methylpropanesulfonic acid, tetraalkylammonium salts, potassium salts of 3-sulfopropylacrylate, etc. A monomer containing a salt of a strong acid can improve solubility in water, and as a result, can improve the developability when the color-forming image-forming material is developed with an aqueous developer, and is therefore preferred as a component of the copolymer.

The proportion of the structural unit represented by the general formula (II) contained in the copolymer using these is preferably 20 to 95% by weight, more preferably 30 to 90% by weight.
% By weight.

The weight average molecular weight of the polymer used in the present invention is preferably 5,000 or more, more preferably 10,000 to 300,000, and the number average molecular weight is preferably 1,000 or more, more preferably Is 200
The range is from 0 to 250,000. Polydispersity (weight average molecular weight /
(Number average molecular weight) is preferably 1 or more, and more preferably 1.1 to 10.

These polymers are random polymers,
Any of a block polymer and a graft polymer may be used, but a random polymer is preferable.

Examples of the solvent used for synthesizing the polymer used in the present invention include tetrahydrofuran, ethylene dichloride, cyclohexanone, methyl ethyl ketone, acetone, methanol, ethanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, -Methoxyethyl acetate, diethylene glycol dimethyl ether, 1-methoxy-2-propanol, 1-methoxy-2-propyl acetate, N, N-dimethylformamide, N, N-
Examples include dimethylacetamide, toluene, ethyl acetate, methyl lactate, ethyl lactate, dimethyl sulfoxide, water and the like. These solvents are used alone or in combination of two or more.

As the radical polymerization initiator used when synthesizing the polymer used in the present invention, known compounds such as an azo initiator and a peroxide initiator can be used.

The compound (B) used in the present invention may be used alone or as a mixture of different kinds.
These compounds are used in an amount of 5 to 9 based on the total solid content of the image forming material.
5% by weight, preferably 10 to 90% by weight is added to the image forming material. Less than 5% by weight and 9
When the content is 5% by weight or more, an image having a sufficient density cannot be obtained.

[(C) Compound selected from carbonyl compound and its equivalent] In the present invention, in the presence of an acid,
The compound which forms a dye skeleton by reacting with the component (B) is (C) a combination of carbonyl compounds such as aldehyde compounds, ketone compounds and quinones, or equivalents of carbonyl compounds such as acetal compounds, imine compounds and amidine compounds. It is.

In the present invention, as the compound (C), it is preferable to use carbonyl compounds such as aldehyde compounds, ketone compounds and quinones, or equivalents of carbonyl compounds such as acetal compounds, imine compounds and amidine compounds. Specifically, pentanal, malonaldehyde, glyoxal, silitol, 1, 2,
4-butanetricarbaldehyde, acrolein, 1,4
Aliphatic aldehydes and ketones such as cyclohexanedione, acetylacetone, 7-octene-3,5-dione, 4-oxo-1-cyclohexane-carboxylic acid, benzaldehyde, terephthalaldehyde, hydroxybenzaldehyde, anisaldehyde, thioanisaldehyde, (2H) naphthalenone, benzophenone, 2,
Aromatic aldehydes and ketones such as 3,4-trihydroxybenzophenone, 1,2-indandione, 1,3,5-triacetylbenzene, N-ethylindole carbaldehyde, N-ethylindole dicarbaldehyde, furfural, Freund , 1- (2-pyridyl)-
Heterocyclic aldehydes and ketones such as 1-butanone and 2-pyridone, and p-benzoquinone, 1,4-naphthoquinone, anthraquinone, 5,8-dioxo-5,8-
Dihydroquinoline, 2,5-dichloro-p-benzoquinone, 2,6-dichloro-p-benzoquinone, 2,5-ditoluenesulfonyloxy-p-benzoquinone, 2,3
And quinones such as -dichloro-1,4-naphthoquinone, 2,3-phenylthio-1,4-naphthoquinone and chloranil. Further, these aldehyde compounds, ketone compounds and quinone compounds may be used as equivalents of corresponding carbonyl compounds such as acetal compounds, imine compounds and amidine compounds.

Of these compounds (C), the compound having a boiling point of 1
Compounds that are liquid at or above 00 ° C. or solid at room temperature are preferred. It is also preferable to use a polymer such as poly (acrolein) or poly (4-formylphenyl methacrylate).

In the present invention, the compound (C) is 2 to 70% by weight, preferably 5 to 6% by weight, based on the total solid content of the image forming material.
Used in an amount of 5% by weight. If the amount is less than 2% by weight, no color image is formed. On the other hand, if it exceeds 70% by weight, it is not preferable in view of the film strength of the formed image.
These compounds may be used alone or in combination of two or more.

In the present invention, an aromatic hydrocarbon compound or a heterocyclic compound substituted with a functional group containing a nitrogen atom is used as the compound (B), and aldehydes or ketones (quinones are used as the compound (C)). Is preferred. The preferred compounding ratio of the compound (B) and the compound (C) can be selected in a suitable range depending on the reaction mechanism of each compound, but is generally from 1: 9 to 1: 9 by weight.
9: 1 is preferable, and 2: 8 to 8: 2 is more preferable.

By simultaneously using the compound (B) having a heteroatom in the molecule and the compound (C) selected from carbonyl compounds and their equivalents in the presence of an acid, the above-mentioned dye skeleton is formed. For example, when two molecules of the compound (B) having a hetero atom and one molecule of the aldehyde which is the compound of (C) react in the presence of an acid, a leuco body of a triphenylmethane dye is formed, and furthermore, oxygen or a suitable oxidizing agent To form a triphenylmethane dye and develop color. Further, one molecule of the compound (B) having a hetero atom and one molecule of the quinone having a substituent, which is the compound of (C),
When the molecule reacts in the presence of an acid, a merocyanine dye is formed and a color is formed.

Such a dye-forming reaction is known as a dye-synthesizing reaction, but these known dye-forming reactions are all reactions carried out in a solution for the purpose of synthesis. There has not been reported any technique in which such a reaction has occurred, and it is quite novel to form an image in combination with the acid generator (A) as in the present invention. The dye skeleton to be formed can be appropriately changed by changing the combination of the compounds (B) and (C). Therefore, the color tone generated by the dye skeleton can also be changed by these combinations.

[Spectral Sensitizer] In the present invention, the above-mentioned acid generator is decomposed by light or heat to generate an acid. In the case where the acid generator is decomposed by light and the light (for example, ultraviolet light) absorbed by the acid generator is irradiated, it is not particularly necessary to use a spectral sensitizer. However, when irradiating light that the acid generator does not absorb, a spectral sensitizer is required. As the sensitizer used when irradiating visible light, a known sensitizer conventionally used for a photoradical polymerization type image recording material can be used. Specific examples include eosins described in JP-A-4-219756 and dyes having a thiazolidinone skeleton described in JP-A-2-244050 and Japanese Patent Application No. 7-23133. However, the image forming material of the present invention does not contain a radically polymerizable polyfunctional monomer. Therefore, it is not clear why the sensitizers effective in the photoradical polymerization type are also effective in the present invention.

In the present invention, it is possible to form an image with a laser emitting infrared rays, but it is necessary to use an infrared absorbing agent as a spectral sensitizer. The infrared absorber used in the present invention has a wavelength of 760 nm to 1200 nm.
Is a dye or pigment that effectively absorbs infrared rays. Preferably, the dye or the pigment has an absorption maximum at a wavelength of 760 nm to 1200 nm.

As the dye, commercially available dyes and known dyes described in literatures such as “Dye Handbook” (edited by the Society of Synthetic Organic Chemistry, published in 1970) can be used. Specifically, dyes such as azo dyes, metal complex salt azo dyes, pyrazolone azo dyes, naphthoquinone dyes, anthraquinone dyes, phthalocyanine dyes, carbonium dyes, quinone imine dyes, methine dyes, cyanine dyes, squarylium dyes, pyrylium salts, and metal thiolate complexes Is mentioned.

Preferred dyes include, for example, those described in
Cyanine dyes described in JP-A-8-125246, JP-A-59-84356, JP-A-59-202829, JP-A-60-78787, etc .;
No. 96, JP-A-58-181690, JP-A-58-1
No. 94595, etc., methine dyes described in
8-112793, JP-A-58-224793, JP-A-59-48187, JP-A-59-73996,
Naphthoquinone dyes described in JP-A-60-52940 and JP-A-60-63744;
Squarylium dyes described in No. 12792, etc.,
Cyanine dyes described in British Patent 434,875 and the like can be mentioned.

Further, a near-infrared absorption sensitizer described in US Pat. No. 5,156,938 is preferably used, and a substituted arylbenzo (thio) described in US Pat. No. 3,881,924 is also preferable. Pyrylium salt, JP-A-57-142645
No. (U.S. Pat. No. 4,327,169) described in JP-A-58-181051, JP-A-58-220143, JP-A-59-41363, and JP-A-59-41363.
Nos. -84248, 59-84249, 59-14
Pyrylium compounds described in JP-A Nos. 6063 and 59-146061, cyanine dyes described in JP-A-59-216146, pentamethine thiopyrylium salts described in U.S. Pat. No. 4,283,475, and the like. Fairness 5-13
Pyrylium compounds disclosed in JP-A-514 and JP-A-5-19702 are also preferably used.

Further, as another preferred example of the dye, the compound represented by the formula (I) in US Pat. No. 4,756,993,
Near-infrared absorbing dyes described as (II) can be mentioned.

Among these dyes, particularly preferred are cyanine dyes, squarylium dyes, pyrylium salts, and nickel thiolate complexes.

The pigment used in the present invention includes
Commercial Pigment and Color Index (CI) Handbook,
"Latest Pigment Handbook" (edited by Japan Pigment Technical Association, 1977), "Latest Pigment Application Technology" (CMC Publishing, 1986), "Printing Ink Technology" CMC Publishing, 1984)
Can be used.

The types of pigments include black pigment, yellow pigment, orange pigment, brown pigment, red pigment, purple pigment,
Blue pigment, green pigment, fluorescent pigment, metal powder pigment, etc.
Polymer-bound dyes. Specifically, insoluble azo pigments, azo lake pigments, condensation azo pigments, chelate azo pigments, phthalocyanine pigments, anthraquinone pigments,
Perylene and perinone pigments, thioindigo pigments, quinacridone pigments, dioxazine pigments, isoindolinone pigments, quinophthalone pigments, dyeing lake pigments,
Azine pigments, nitroso pigments, nitro pigments, natural pigments, fluorescent pigments, inorganic pigments, carbon black and the like can be used.
Preferred among these pigments is carbon black.

These dyes or pigments are used in an amount of 0.01 to 50% by weight, preferably 0.1% by weight, based on the total solid content of the image recording material.
To 10% by weight, particularly preferably 0.5 to 10% in the case of a dye.
% By weight, particularly preferably 1.0 to 10% by weight in the case of a pigment.
In the image recording material. If the amount of the pigment or the dye is less than 0.01% by weight, the sensitivity is lowered, and if it exceeds 50% by weight, the non-image area is stained during printing.

These dyes or pigments may be added to the same layer as other components, or another layer may be provided and added thereto. In particular, when the color of these dyes or pigments hinders, it is preferable to add the dye or pigment to another layer and remove this layer after image formation.

Generally, in the case of a visible light sensitizer, the mechanism of action is as described in “sensitizers” (edited by Katsumi Tokumaru and Shin Okawara, Kodansha Co., Ltd.) and the like. And so on. However, the mechanism of action of infrared sensitizers is not sufficiently clear. For example, it is said that the infrared absorber absorbs infrared rays and then generates heat to thermally decompose the acid generator.

[Other Components] In the present invention, various compounds other than these may be further added, if necessary.
For example, alkyl ethers (for example, ethyl cellulose and methyl cellulose) for improving coating properties, surfactants (for example, fluorine-based surfactants), film flexibility,
A plasticizer (for example, tricresyl phosphate, dimethyl phthalate, dibutyl phthalate, trioctyl phosphate, tributyl phosphate, tributyl citrate, polyethylene glycol, polypropylene glycol, etc.) for imparting wear resistance can be added. The amount of these additives varies depending on the purpose of use, but is generally 0.05 to 20% by weight based on the total solids of the image forming material.
It is.

In the image forming material of the present invention, a known polymer such as a novolak resin, an acrylate resin, a polyurethane resin, or a polyester resin may be added.
A preferable addition amount is 30% by weight or less in the image recording material.

In the present invention, if necessary, an oxidizing agent for accelerating color formation can be added. Preferred oxidizing agents include inorganic oxidizing agents such as manganese dioxide, and organic oxidizing agents such as triazenes, organic peroxides, and azo compounds. The addition amount of these oxidizing agents is 20% by weight or less based on the total solid content of the image forming material.

In the image forming material of the present invention, each of the above components may be usually dissolved in a solvent and used as a solution, but it is preferable to use the solution by coating it on a suitable support depending on the purpose.
As the solvent used here, ethylene dichloride,
Cyclohexanone, methyl ethyl ketone, methanol,
Ethanol, propanol, ethylene glycol monomethyl ether, 1-methoxy-2-propanol, 2-
Methoxyethyl acetate, 1-methoxy-2-propyl acetate, dimethoxyethane, methyl lactate, ethyl lactate, N, N-dimethylacetamide, N, N-dimethylformamide, tetramethylurea, N-methylpyrrolidone, dimethylsulfoxide, sulfolane, Examples thereof include γ-butyl lactone, toluene, and water, but are not limited thereto. These solvents are used alone or as a mixture. The concentration of the above components (total solids including additives) in the solvent is preferably 1 to 50% by weight. The amount of coating (solid content) on the support obtained after coating and drying varies depending on the application, but generally ranges from 0.5 to 100.
g / m ² is preferred. Various methods can be used as the method of coating, and examples thereof include bar coater coating, spin coating, spray coating, curtain coating, dip coating, air knife coating, blade coating, and roll coating.

[Support] In the present invention, various supports can be used according to the purpose. Preferred supports are dimensionally stable plates, such as paper, coated paper, plastics (eg, polyethylene, polypropylene,
Paper, metal plate (eg, aluminum, zinc, copper, etc.), plastic film (eg, cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate butyrate, cellulose nitrate, polyethylene terephthalate, polyethylene naphthalene) Carboxylate, polyethylene, polystyrene, polypropylene, polycarbonate, polyvinyl acetal, etc.), and paper or plastic film on which the above-mentioned metal is laminated or vapor-deposited.

Preferred supports include paper, coated paper,
Laminated paper, polyester film or aluminum plate may be used.

The color image forming material of the present invention can be recorded by radiation or heat emitted from various light sources. For example,
It can record with ultraviolet, visible or infrared light. These light sources may be lamps or lasers.
In the present invention, an ultraviolet lamp or a wavelength of 760 n
It is preferable that the image is exposed by a solid-state laser or a semiconductor laser that emits infrared rays of m to 1200 nm. Further, thermal recording by a thermal head is also preferable. In the present invention, a post-exposure bake may be performed. When performing the heat treatment, it is preferable that the heat treatment is performed within a range of 60 ° C. to 150 ° C. for 5 seconds to 5 minutes. As the heating method,
Conventionally known various methods can be used. For example,
Heating with a panel heater or a ceramic heater, a method using a lamp, and the like are included.

After the heat treatment, if necessary, the non-image area of the color image forming material of the present invention can be removed with water or an alkaline aqueous solution. As a preferable aqueous solution, various alkali aqueous solutions conventionally known for a lithographic printing plate or for a proof can be used.

[0075]

The present invention will be described in detail with reference to the following examples, but the present invention is not limited to these examples.

Synthesis of Polymer [BP-1] 7.2 g (corresponding to 0.21 mol) of an oil dispersion of NaH and 50 ml of tetrahydrofuran were placed in a 500-ml flask equipped with a stirrer and a condenser, and placed in an ice-water bath. With stirring. To this mixture, add 24.60 g of indole
(0.21 mol) dissolved in 100 ml of tetrahydrofuran was added dropwise little by little. After the addition, the ice water bath was removed and the mixture was stirred at room temperature for 1 hour. Next, 49.29 g of 2-chloroethyl-p-toluenesulfonate (0.2
1 mol), and the mixture was stirred and reacted under heating and refluxing for 15 hours. After completion of the reaction, insolubles were removed by filtration, and the mixture was concentrated under reduced pressure. Further, the reaction mixture was purified by column chromatography using silica gel to obtain 1- (2
15.4 g of (-chloroethyl) indole were obtained.

Next, 20 was equipped with a stirrer and a cooling pipe.
In a flask of 0 ml capacity, 15.4 g of 1- (2-chloroethyl) indole and 21.3 of potassium methacrylate.
g, 7.1 g of potassium iodide, 40 ml of N, N-dimethylformamide and a small amount of hydroquinone.
C. and stirred for 2.5 hours. After completion of the reaction, insolubles were removed by filtration, and the mixture was concentrated under reduced pressure. Further, the reaction mixture was purified by column chromatography using silica gel to obtain 15.5 g of 1- (2-methacryloyloxyethyl) indole.

Further, a device equipped with a stirrer and a cooling pipe was used.
14.75 g of 1-methoxy-2-propanol was placed in a 00-ml flask, and heated to 75 ° C. under a nitrogen stream. While stirring the flask, 11.28 g of 1- (2-methacryloyloxyethyl) indole, 1.36 g of methacrylic acid, 0.0748 g of V-601 (azo polymerization initiator manufactured by Wako Pure Chemical Industries, Ltd.), and 1-methoxy-
A mixture of 14.75 g of 2-propanol was added dropwise over 2.5 hours. After the dropwise addition, 0.0748 g of the polymerization initiator V-601 was added again, and the mixture was stirred at 75 ° C for 3 hours. After completion of the reaction, the mixture was cooled to room temperature, 50 ml of methanol was added, and the mixture was poured into 1 liter of water with stirring. The precipitate was collected by filtration and dried under reduced pressure to obtain 12.6 g of the polymer [BP-1] of the present invention. In addition, when the weight average molecular weight was measured by GPC, it was 54,000 (standard of polystyrene).

Synthesis of polymer [BP-2] 3- (2-hydroxyethyl) indole was placed in a 500-ml flask equipped with a stirrer and a condenser.
18 g (0.15 mol), triethylamine 16.19
g (0.16 mol), 4- (N, N-dimethylamino)
2.44 g (0.02 mol) of pyridine, ethyl acetate 20
0 ml and a small amount of hydroquinone were added, and the mixture was stirred in an ice water bath. 27.7 methacrylic anhydride was added to this mixture.
5 g (0.18 mol) was added dropwise little by little. After the addition was completed, the ice-water bath was removed and the mixture was stirred at room temperature for 3 hours. After completion of the reaction, insolubles were removed by filtration, and the mixture was concentrated under reduced pressure.
Further, the reaction mixture was purified by column chromatography using silica gel to obtain 25.0 g of 3- (2-methacryloyloxyethyl) indole.

Further, a device equipped with a stirrer and a cooling pipe was used.
14.75 g of 1-methoxy-2-propanol was placed in a 00-ml flask, and heated to 75 ° C. under a nitrogen stream. While stirring the inside of the flask, 11.28 g of 3- (2-methacryloyloxyethyl) indole, 1.36 g of methacrylic acid, 0.0748 g of V-601 (azo polymerization initiator manufactured by Wako Pure Chemical Industries, Ltd.), and 1-methoxy-
A mixture of 14.75 g of 2-propanol was added dropwise over 2.5 hours. After the completion of dropping, 0.0748 of V-601 was used.
g was added again and stirred at 75 ° C. for 3 hours. After completion of the reaction, the mixture was cooled to room temperature, 50 ml of methanol was added, and the mixture was poured into 1 liter of water with stirring. The precipitate was collected by filtration and dried under reduced pressure to obtain the polymer [BP-2] 1 of the present invention.
2.4 g were obtained. In addition, when the weight average molecular weight was measured by GPC, it was 72,000 (polystyrene standard).

Synthesis of Polymer [BP-3] 2-Aminobenzothiazole was reacted with acrylic acid chloride under basic conditions to synthesize 2- (acryloylamino) benzothiazole. Further, copolymerization with ethyl acrylate was performed to obtain a polymer [BP-3] according to the present invention. The weight average molecular weight measured by GPC was 106,000 (polystyrene standard).

Table 1 shows the structures of [BP-1] to [BP-3].
Shown in

[0083]

[Table 1]

(Example 1) Use as a proof The following solution [V] was prepared, and this solution was treated with surface-treated P
The composition was applied to an ET film and dried at 100 ° C. for 1 minute to obtain a color image forming material [V-1]. The weight of the coating film after drying was 1.5 g / m ² . The color of the coated film was slightly yellowish but almost colorless.

Solution [V] Acid generator [SH-1] 0.15 g Polymer [BP-1] 1.6 g Aldehyde [BA-1] 0.4 g Fluorosurfactant 0.06 g (MegaFac F-177) , Manufactured by Dainippon Ink and Chemicals, Inc.) Methyl ethyl ketone 15 g 1-methoxy-2-propanol 5 g Methyl alcohol 7 g

Among the components of the solution [V], the component (A) of the present invention is an acid generator [SH-1], and among the compounds which cause a reaction to form a dye skeleton in the presence of an acid, The polymer [BP-1] is a component having (B) in the side chain, and the aldehyde [BA-1] is a component (C). The acid generator [SH-1] and the aldehyde [BA-
1] is shown below.

[0087]

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[0088]

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When the obtained image-forming material [V-1] was exposed to ultraviolet light, the exposed portion developed a purple color. Further, when the panel heater was heated at 90 ° C. for 15 seconds, the color density increased. The developed image was transferred to paper using a heat roller, but the color of the image portion did not change.

(Example 2) Use as proof The image forming material [V-1] obtained in Example 1 was exposed and heated in the same manner as in Example 1. Next, when immersed in an alkaline aqueous solution having the following composition, the unexposed portions were dissolved and removed. At this time, the color of the image portion was kept purple. Further, the developed image was transferred to paper using a heat roller, but the color of the image portion did not change.

[Aqueous alkaline solution] Sodium hydrogen carbonate 10 g Sodium carbonate 20 g Sodium butylnaphthalenesulfonate 50 g Water 920 g

Example 3 Use as Thermal Paper The following solution [W] was prepared, and this solution was applied to paper.
After drying at 0 ° C. for 1 minute, a color image forming material [W-1] was obtained. The weight of the coating film after drying was 1.6 g / m ² . The color of the coated surface was almost colorless.

Solution [W] Acid generator [SH-2] 0.15 g Polymer [BP-1] 1.6 g Aldehyde [BA-2] 0.4 g Fluorosurfactant 0.06 g (MegaFac F-177) , Manufactured by Dainippon Ink and Chemicals, Inc.) Methyl ethyl ketone 15 g 1-methoxy-2-propanol 5 g Methyl alcohol 7 g

The structures of the acid generator [SH-2] and the aldehyde [BA-2] used are shown below.

[0095]

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[0096]

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When the obtained image forming material [W-1] was thermally printed with a thermal head, the thermally printed portion was colored pink. The developed image was rubbed in water containing methanol, but no change was observed.

Example 4 The following solution [X] was prepared, and this solution was applied to a PET film and dried at 100 ° C. for 1 minute to obtain a color image forming material [X-1]. The weight of the coating film after drying was 1.0 g / m ² . The color of the applied film was green.

Solution [X] Acid generator [SH-3] 0.15 g Polymer [BP-1] 1.6 g Aldehyde [BA-1] 0.4 g Infrared absorber [KZ-1] 0.1 g Fluorine-based interface Activator 0.06 g (MegaFac F-177, manufactured by Dainippon Ink and Chemicals, Inc.) Methyl ethyl ketone 15 g 1-methoxy-2-propanol 20 g

The structures of the acid generator [SH-3] and the infrared absorber [KZ-1] used are shown below.

[0101]

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[0102]

Embedded image

When the obtained image-forming material [X-1] was exposed to a semiconductor laser emitting infrared light having a wavelength of about 830 to 850 nm, the exposed portion developed a purple color. further,
Heating at 90 ° C. for 15 seconds with a panel heater increased the color density.

Example 5 Use as Dry Lith Film The following solution [Y] was prepared, and this solution was applied to a PET film and dried at 100 ° C. for 1 minute to obtain a color-forming image forming material [Y-1]. Obtained. The weight of the coating film after drying is 2.0 g / m
^{Was 2} . The color of the applied film was almost colorless.

Solution [Y] Acid generator [SH-3] 0.15 g Polymer [BP-1] 1.6 g Aldehyde [BA-1] 0.4 g Fluorinated surfactant 0.06 g (MegaFac F-177) , Manufactured by Dainippon Ink and Chemicals, Inc.) Methyl ethyl ketone 15 g 1-methoxy-2-propanol 5 g

Next, 0.2 g of infrared absorbent [KZ-1]
And a solution obtained by dissolving 1.2 g of poly (benzyl methacrylate) in 10 g of methyl ethyl ketone and 5 g of 1-methoxy-2-propanol were applied to a PET film.
It dried at 1 degreeC for 1 minute, and obtained the coating film [Y-2] containing an infrared absorber.

The obtained [Y-1] and [Y-2] were adhered so that the respective coated surfaces were in contact with each other, to obtain a color-forming image forming material [Y-3]. The obtained [Y-3] was converted to a wavelength of 83
Exposure was performed with a semiconductor laser emitting infrared light of about 0 to 850 nm. After the exposure, [Y-2] was peeled off.
In [1], a colored image was formed.

[0108] The planographic printing plate VPS manufactured by Fuji Photo Film Co., Ltd. was passed through [Y-1] on which the color image was formed.
Was exposed to ultraviolet light under reduced pressure. The exposed VPS is developed with a developing solution DP-4 (1: 8 water dilution) manufactured by Fuji Photo Film Co., Ltd., and treated with a rinsing solution FR-3 (1: 7).
Further, the plate surface was treated with gum GU-7 (1: 1) and printed with a Heidel KOR-D machine. Many good prints without stains on the non-image area were obtained.

(Example 6) Solution [V] used in Example 1
Has the following structure as an acid generator [SH-
4], and a color-forming image forming material [V-2] was obtained in the same manner as in Example 1 except that [BP-2] was used as the polymer. The color of the applied film was almost colorless.

[0110]

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When the obtained image forming material [V-2] was exposed to ultraviolet rays, the exposed portions developed a blue color.

(Example 7) Solution [W] used in Example 3
In the same manner as in Example 3, except that [BP-3] was used as the polymer, the color image forming material [W-
2] was obtained. When the obtained image forming material [W-2] was thermally printed with a thermal head, the thermally printed portion was colored orange. The developed image was rubbed in water containing methanol, but no change was observed.

Example 8 The following solution [Z] was prepared, and this solution was applied to a PET film and dried at 100 ° C. for 1 minute to obtain a color image forming material [Z-1]. The weight of the coating film after drying was 1.5 g / m ² .

Solution [Z] Acid generator [SH-1] 0.15 g Polymer [BP-1] 1.0 g Quinone [BA-3] 0.4 g Poly (benzyl methacrylate) 0.5 g Fluorosurfactant 0 0.06 g (MegaFac F-177, manufactured by Dainippon Ink and Chemicals, Inc.) Methyl ethyl ketone 15 g 1-methoxy-2-propanol 5 g Methyl alcohol 7 g

The structure of the quinone [BA-3] used is shown below.

[0116]

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When the obtained image forming material [Z-1] was exposed to ultraviolet rays, the exposed portions developed a blue-violet color.

(Comparative Example 1) Solution [V] used in Example 1
In Example 1, a color image forming material [Q-1] was obtained in the same manner as in Example 1, except that the acid generator [SH-1] as the component (A) was omitted. The obtained [Q-1] was exposed to ultraviolet light, but no color formation was observed.

(Comparative Example 2) Solution [V] used in Example 1
In this Example, a color-forming image forming material [Q-2] was obtained in the same manner as in Example 1 except that the aldehyde [BA-1] as the component (C) was omitted. The obtained [Q-2] was exposed to ultraviolet light, but no color formation was observed.

[0120]

The color-forming image-forming material of the present invention has the advantage that a color-forming image can be recorded by light or heat without using a leuco dye, and that the color-formed image has excellent film strength. Have.

Claims (1)

[Claims] 1. A compound which (A) generates an acid by light or heat, (B) an aromatic hydrocarbon compound or a heterocyclic compound substituted with a functional group containing a hetero atom in the molecule, and (C) a carbonyl compound And a compound selected from its equivalents, and by an acid generated by light or heat,
A color-forming image-forming material, wherein (B) and (C) cause a reaction to form a dye skeleton.