JPH03132664A - Multicolor image forming method - Google Patents

Abstract

PURPOSE:To obtain the multicolor images which are excellent in both of brightness and saturation with a high sensitivity and high resolution by dry processing by successively executing a method for forming a single color image from a thermally diffusing dye on image receiving paper to a photosensitive of different color tones, thereby forming the multicolor images. CONSTITUTION:The photesensitive body 1 is laminated with the light transmission control layer 2 contg. a photosensitive silver halide 4, an org. silver slat and a reducing agent 5 and a polymerized layer 3 contg. a polymerizable monomer, a photopolymn. initiator, and a thermally diffusive dye 6 forming color images. The light transmission control layer 2 makes pattern formation by a difference in the transmittance of light of the wavelength to cleave the photospolymn. initiator in the polymerized layer 3 by the silver patterns, etc., formed in an image exposing stage and heating stage. The polymerized layer 3 forms polymerized patterns according to transmittance patterns when the layer is subjected to a full surface exposing stage and further, forms the thermally diffusive dye images corresponding to the polymerized patterns onto the image receiving paper when this layer is laminated with the image receiving paper and is heated. Thus, the multicolor images which are both excellent in the brightness and the saturation are formed on the image receiving paper with the high sensitivity and high resolution by the dry processing.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention involves forming a polymerized latent image by forming a portion made of a polymer in an image-like manner on a layer containing a photopolymerizable monomer, and forming a polymerized latent image from the polymerized latent image. The present invention relates to a multicolor image forming method using dry processing for forming a desired multicolor image.

[Conventional technology]

Energy used to form or record images includes light, sound, electricity, magnetism, heat, particle beams (electron beams, X-rays), and chemical energy.
Electricity, thermal energy, or a combination of these are often used.

For example, image forming methods using a combination of light energy and chemical energy include methods using silver salt photography, diazo copying paper, and the like. Further, as a method using a combination of light energy and electric energy, there is an electrophotographic system. Furthermore, methods of utilizing thermal energy include methods using thermal recording paper, transfer recording paper, etc.
As methods that utilize electrical energy, methods using electrostatic recording paper, current-carrying recording paper, discharge recording paper, etc. are known.

Among the image forming methods described above, silver salt photography is one that allows high resolution images to be obtained. However, silver salt photography requires complex development and fixing processes using liquid agents, drying processes for images (prints), and the like.

Therefore, development of an image forming method that allows image formation by simple dry processing is being actively conducted.

For example, there is a sublimation transfer method in which an ink donor sheet containing a sublimable dye is heated using a thermal head in accordance with an image signal, and the sublimable dye in the heated area is transferred to an image receiving paper, but this method has a low resolution. Depends on the thermal head and does not provide sufficient resolution.

In addition, in a full-color image forming method using a photopolymerizable composition such as Color Art, the negative that forms the polymerized and unpolymerized areas is a wet-processed lithium film, and it is difficult to draw directly with a laser without a negative. However, the absorption wavelength range of the photopolymerization initiator is short, so the reaction will not start unless a gas laser is used, and the sensitivity of the photopolymerization initiator is low, so it is necessary to irradiate it with a very high-power laser for a long time. Otherwise, it has drawbacks such as no reaction and is not practical.

[Problem to be solved by the invention]

The object of the present invention is to form a photopolymerizable layer containing a polymer in an imagewise manner by forming a polymeric latent image, and to form a desired multicolor image from the polymerized latent image. An object of the present invention is to provide a method for forming a multicolor image by processing.

[Means to solve the problem]

As a result of intensive studies, the present inventors have discovered that in a multicolor image forming method in which a multicolor image is obtained by sequentially recording a plurality of monochrome images of different color tones, at least a polymerizable monomer, a photopolymerization initiator, a monochrome image (I) Image exposure step (It) Heating step (m) Full-surface exposure step (IV) A process of laminating with image-receiving paper and thermal transfer is performed to form a monochromatic image made of heat-diffusible dye on the image-receiving paper, which is sequentially performed on photoreceptors of different tones to form a multicolor image. It has been discovered that the above object of the present invention can be achieved by a multicolor image forming method characterized by forming a multicolor image.

The present invention will be explained in detail below.

A photoreceptor suitably used in the present invention will be explained.

FIG. 1 is a schematic diagram of a photoreceptor 1 suitably used in the multicolor image forming method of the present invention.

The photoreceptor 1 includes a light transmission control layer 2 containing at least a photosensitive silver halide 4, an organic silver salt, and a reducing agent 5, and at least a polymerizable monomer, a photopolymerization initiator, and a heat-diffusible dye that forms a color image. The photoreceptor is a photoreceptor in which a polymer layer 3 containing 6 as a component is laminated, and may or may not include a base material.

Here, the light transmission control layer 2 refers to the difference in the transmittance of light at a wavelength that can cleave the photopolymerization initiator in the polymerization layer 3 due to the silver pattern or reaction product pattern formed through the image exposure process and heating process. The polymer layer 3 functions to form a pattern, and when the entire surface exposure process is performed, a polymer pattern is formed according to the transmittance pattern, and by further laminating with image receiving paper and heating, the polymer layer 3 generates heat according to the polymer pattern. A substance that functions to form a diffusible dye image on image-receiving paper.

In other words, when trying to form a full-color image using the subtractive color mixing method, a yellow photoreceptor consisting of a polymer layer containing a yellow heat-diffusible dye and a light transmission control layer, a polymer layer containing a magenta heat-diffusible dye, and a light transmission control layer are used. Three types of photoreceptors are used: a magenta photoreceptor consisting of a transmission control layer, and a cyan photoreceptor consisting of a polymer layer containing a cyan heat-diffusible dye and a light transmission control layer.

The light transmission control layer may be used in combination with each polymer layer, or may be a common light transmission control layer.

These polymerized layers are composed of a photopolymerization initiator that absorbs in the wavelength range of light that passes through the light transmission control layer, and radicals that absorb light and are generated by cleavage or hydrogen abstraction, which propagate to form polymerized parts. It contains as essential components a polymerizable compound having an unsaturated double bond to be obtained and a heat-diffusible dye that diffuses depending on the degree of polymerization of the polymerized part.

It is desirable that the absorption wavelength range of the photopolymerization initiator is different from the absorption wavelength range of the polymerizable compound and the heat diffusive substance. For example, when forming a multicolor image by subtractive color mixing, yellow heat diffusible dye is The dye transfer control layer has an absorption wavelength of 2
A photopolymerization initiator having an absorption wavelength range of 90 to 380 nm is preferable, and a photopolymerization initiator having an absorption wavelength range of 310 to 360 nm is more preferable. It is preferable to use a photopolymerization initiator with an absorption wavelength range of 340 to 440 nm, more preferably 360 to 420 nm, for the dye transfer control layer containing a magenta heat-diffusible dye.
Preferably, the material has an absorption wavelength range of nm.

The dye transfer control layer containing cyan heat diffusible dye contains 4
It is preferable to use a photopolymerization initiator having an absorption wavelength range of 10 to 500 nm, and more preferably a photopolymerization initiator having an absorption wavelength range of 430 to 490 nm. When the thermally diffusive substance is a coupler and a color image is to be formed by a coloring reaction, a photopolymerization initiator having absorption in a region without absorption wavelength of the coupler may be used.

Such photopolymerization initiators include carbonyl compounds,
Examples include sulfur compounds, halogen compounds, redox photopolymerization initiators, and the like.

Specifically, carbonyl compounds include diketones such as benzyl, 4,4'-dimethoxybenzyl, diacetyl, and camphorquinone; benzophenones such as 4,4'-diethylaminobenzophenone and 4°4'-dimethoxybenzophenone; Acetophenones such as acetophenone and 4'-methoxyacetophenone; Benzoin alkyl ethers; Thioxanthone such as 2-cyclothioxanthone, 2,5-diethylthioxanthone, and thioxanthone-3-carboxylic acid β-methoxyethyl ester; Chalcone and styryl ketones having dialkylamino group, 3-
3'carbonylbis(7-medoxycoumarin), 3-3
Examples include coumarins such as carbonylbis(7-dinithylaminocoumarin).

Examples of the sulfur compound include dibenzothiazolyl sulfide, delphenyl sulfide, and disulfides.

Examples of halogen compounds include carbon tetrabromide, quinolinesulfonyl chloride, and s-
Examples include triazines.

Redox-based photopolymerization initiators include those used in combination with trivalent iron ion compounds (e.g. ferric ammonium citrate) and peroxide, and those used in combination with photoreducible dyes such as riboflavin and methylene blue and triethanol. Examples include those using a combination of reducing agents such as amines and ascorbic acid.

Moreover, in the photopolymerization initiators described above, more efficient photopolymerization can be performed by combining two or more types.

Examples of such a combination of photopolymerization initiators include a combination of chalcone, styryl ketones, or coumarins having a dialkylamino group, and S-) riazine or camphorquinone having a trihalomethyl group.

In the present invention, as the polymerizable polymer contained in the polymerization layer constituting the polymerization element, a compound having at least one reactive vinyl group in one molecule can be used. One or more selected from the group consisting of a reactive vinyl group-containing oligomer, and a reactive vinyl group-containing polymer can be used.

The reactive vinyl groups of these compounds include styrene vinyl groups, vinyl acrylate groups, vinyl methacrylate groups, allyl vinyl groups, vinyl ethers, and ester vinyl groups such as vinyl acetate, which have polymerization reactivity. Examples include substituted or unsubstituted vinyl groups.

Specific examples of polymerizable monomers that satisfy these conditions are as follows.

For example, styrene, methylstyrene, chlorstyrene,
Bromostyrene, methoxystyrene, dimethylaminostyrene, cyanostyrene, nitrostyrene, hydroxystyrene, aminostyrene, carboxystyrene, acrylic acid, methyl acrylate, ethyl acrylate, cyclohexyl acrylate, acrylamide, methacrylic acid,
Methyl methacrylate, ether methacrylate, propyl methacrylate, butyl methacrylate, phenyl methacrylate, cyclohexyl methacrylate, vinylpyridine,
N-vinylpyrrolidone, N-vinylimidazole, 2-
Vinylimidazole, N-methyl-2-vinylimidazole, propyl vinyl ether, butyl vinyl ether, isobutyl vinyl ether, β-chloroethyl vinyl ether, phenyl vinyl ether, p-methylphenyl vinyl ether, p-chlorophenyl vinyl ether, etc. monomers such as divinylbenzene, distyryl oxalate, distyryl malonate, distyryl succinate, distyryl glutarate, distyryl adipate, distyryl maleate, distyryl fumarate, β, β-dimethylglutarate, distyryl 9-promoglutar Distyryl acid, α,α′-dichloroglutarate distyryl, distyryl terephthalate, di(ethyl acrylate) oxalate, di(methyl ethyl acrylate) oxalate,
Malonic acid di(ethyl acrylate), malonic acid di(methyl ethyl acrylate), succinic acid di(ethyl acrylate), glutaric acid di(ethyl acrylate), adipic acid di(ethyl acrylate), maleic acid di(diethyl acrylate), fumaric acid Acid di(ethyl acrylate)
, β, β-dimethylglutaric acid di(ethyl acrylate), ethylene diacrylamide, propylene diacrylamide, 1,4-phenylene diacrylamide, ■, 4
-phenylene bis(oxyethyl acrylate), 1.
4-phenylenebis(oxymethylethyl acrylate), 1, 4-bis(acryloyloxyethoxy)cyclohexane, 1゜4-bis(acryloyloxymethylethoxy)cyclohexane, ■, 4-bis(acryloyloxyethoxycarbamoyl)benzene, 1 ,4-
Bis(acryloyloxymethylethoxycarbamoyl)benzene, l,4-bis(acryloyloxyethoxycarbamoyl)cyclohexane, bis(acryloyloxyethoxycarbamoylcyclohexyl)methane,
Dioxalate (ethyl methacrylate), dioxalate (methyl ethyl methacrylate), dimalonate (ethyl methacrylate), dimalonate (methyl ethyl methacrylate), disuccinate (ethyl methacrylate), disuccinate (methyl ethyl methacrylate) , glutaric acid di(ethyl methacrylate), adipic acid di(ethyl methacrylate), maleic acid di(ethyl methacrylate), fumaric acid di(ethyl methacrylate), fumaric acid di(methyl ethyl methacrylate), β,β′-dimethylglutaric acid Divalent monomers such as di(ethyl methacrylate), l,4-phenylene bis(oxyethyl methacrylate), 1,4-bis(methacryloyloxyethoxy)cyclohexane acryloyloxyethoxyethyl vinyl ether; for example, pentaerythritol triacrylate, pentaerythritol triacrylate, Erythritol trimethacrylate, pentaerythritol tri(hydroxystyrene), cyanuric acid triacrylate, nuric acid trimethacrylate, 1
,1.1-)limethylolpropane triacrylate,
1,1゜1-trimethylolpropane trimethacrylate, cyanuric acid tri(ethyl acrylate)), 1,1゜1-trimethylolpropane tri(ethyl acrylate), cyanuric acid tri(ethyl vinyl ether), l.

1, 1-,) condensate of limethylolpropane tri(toluene diisocyanate) and hydroxyethyl acrylate, 1. 1. Trivalent monomers such as a condensate of 1-1-limethylolpropane tri(hexane diisocyanate) and p-hydroxystyrene; for example, tetravalent monomers such as ethylenetetraacrylamide and propylenetetraacrylamide; Examples of polymerizable monomers include oligomers or polymers with reactive vinyl groups left at their ends, or oligomers or polymers with reactive vinyl groups attached to their side chains.

Incidentally, as described above, two or more kinds of these polymerizable monomers may be used.

In the present invention, the heat-diffusible dyes contained in the polymerization layer include, for example, monoazo dyes, thiazoleazo dyes, anthraquinone dyes, triallylmethane dyes, rhodamine dyes, naphthol dyes, triarylmethane dyes, fluoran dyes, Examples include phthalide dyes and color couplers. In general, the lower the molecular weight of a heat-diffusible dye, the greater the heat-diffusibility.Furthermore, for example, a dye having many polar groups such as a carboxyl group, an amino group, a hydroxyl group, a nitro group, or a sulfone group has a low heat-diffusivity. Therefore, in the present invention, a dye having a desired thermal diffusivity may be appropriately selected based on the molecular weight and functional group depending on the crosslinking density and heating conditions of the photosensitive recording material.

Further, as a color developer in the image-receiving layer for reacting with the color-forming coupler to exhibit a color, zinc oxide, calcium sulfate, novolak type resin, and zinc 3,5-dimethyl-t-diptylsalicylate can be used.

In the present invention, the polymer layer is preferably formed to have a thickness of about 0.1 μm to 2 mm, preferably about 1 μm to 0.1 mm.

The binder that can be used in the present invention can be selected from a wide range of resins, but specific examples include nitrocellulose, cellulose phosphate, cellulose sulfate, cellulose acetate, cellulose propionate, cellulose butyrate, cellulose myristate. , cellulose palmitate,
Cellulose esters such as cellulose acetate/propionate, cellulose acetate/butyrate; cellulose ethers such as methyl cellulose, ethyl cellulose, propyl cellulose, butyl cellulose; e.g. polystyrene, polyvinyl chloride, polyvinyl acetate, polyvinyl butylade, polyvinyl acecool , vinyl resins such as polyvinyl alcohol, polyvinylpyrrolidone; copolymer resins such as styrene-butadiene copolymer, styrene-acrylonitrile copolymer, styrene-butadiene-acrylonitrile copolymer, vinyl chloride-vinyl acetate copolymer; e.g. polymethyl methacrylate,
Acrylic resins such as polymethyl acrylate, polybutyl acrylate, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyacrylonitrile; polyesters such as polyethylene terephthalate; for example, poly(4,4-isopropylidene, diphenylene-co-1, 4-cyclohexylene dimethylene carbonate), poly(ethylenedioxy-3,3'-phenylene thiocarbonate), poly(4,4'-isopropylidene diphenylene carbonate coated terephthalate),
Polyacrylate resins such as poly(44'-isopropylidene diphenylene carbonate), poly(4,4'-5ec-butylidene diphenylene carbonate), poly(4,4'-isopropylidene diphenylene carbonate-block oxyethylene) : Polyamides: Polyimides; Epoxy resins; Phenol resins; For example, polyolefins such as polyethylene, polypropylene, and chlorinated polyethylene; and natural polymers such as gelatin.

The light transmission control layer of the photosensitive element contains a photosensitive silver halide, an organic silver salt, and a reducing agent as essential components.

Silver halides that can be used include silver chloride, silver bromide, silver iodide, silver chlorobromide, silver chloroiodide, silver iodobromide, and silver chloroiodobromide. The composition may be uniform or have different multilayered structures. Also, two or more types of silver halides with different halogen compositions, grain sizes, grain size distributions, etc. may be used in combination. It may be spectrally sensitized or chemically sensitized.

Examples of the organic silver salt include silver salts with aliphatic carboxylic acids, aromatic carboxylic acids, thiocarbonyl group compounds having a mercapto group or α-hydrogen, and imino group-containing compounds.

Aliphatic carboxylic acids include acetic acid, butyric acid, succinic acid, sebacic acid, adipic acid, oleic acid, linoleic acid, linoleic acid, tartaric acid, palmitic acid, stearic acid, hebenic acid, camphoric acid, etc. Since the smaller the number of carbon atoms in the silver salt, the more unstable the silver salt is, it is preferable to use a silver salt having an appropriate number of carbon atoms.

Examples of aromatic carboxylic acids include benzoic acid derivatives, quinolinic acid derivatives, naphthalenecarboxylic acid derivatives, salicylic acid derivatives, gallic acid, tannic acid, phthalic acid, phenylacetic acid derivatives, and pyromellitic acid.

As the thiocarbonyl group compound having a mercapto group or α-hydrogen, 3-mercapto-4-phenyl-1,2
, 4-) Riazole, 2-mercaptobenzimidazole, 2-mercapto-5-aminothiadiazole, 2-
Mercaptobenzothiazole, S-alkylthioglycolic acid (alkyl group having 12 to 22 carbon atoms), dithiocarboxylic acids such as dithioacetic acid, thioamides such as thiostearamide, 5-carboxy-1-methyl-2-phenyl-
Mercapto compounds described in U.S. Pat. No. 4,123,274, such as 4-thiopyridine, mercaptotriane, 2-mercaptobenzoxazole, mercaptooxadiazole, or 3-amino-5-benzylthio-1,2,4-triazole, Can be mentioned.

As a compound containing an imino group, Japanese Patent Publication No. 44-30
Benzotriazole or its derivatives described in No. 270 or No. 45-18416, such as benzotriazole, alkyl-substituted benzotriazoles such as methylbenzotriazole, halogen-substituted benzotriazoles such as 5-chlorobenzotriazole, carboxyl-substituted benzotriazoles such as butylcarboimidobenzotriazole, etc. imidobenzotriazoles,
Nitrobenzotriazoles described in JP-A-58-118639, sulfonebenzotriazole, carboxybenzotriazole or a salt thereof, or hydroxybenzotriazole, etc., described in JP-A-58-115638, U.S. Pat. No. 4,220,709 1.2゜4-
Representative examples include triazole, LH-tetrazole, carbazole, saccharin, imidazole and derivatives thereof.

Examples of the reducing agent that can be used in the present invention include the reducing agents described in [Basics of Photographic Optics, Non-Silver Salt Edition, p. 250J, secondary color developing agents, secondary color developing agents, and the like. These include, for example, phenols, hydroquinones, catechols, p-aminophenols, p-substituted aminophenols, p-)unilenediamines, 3-pyrazolidones, resorcinols, pyrogallols, 0- Aminophenols, m-aminephenols, m-fuynylenediamines, 5-pyrazolones, alkylphenols, alkoxyphenols, naphthols, aminonaphthols, naphthalene diols, alkoxynaphthols, hydrazines, hydrazones , hydroxychroman/hydroxyclamans, sulfonamide phenols, aminonaphthols, ascorbic acids, hydroxyindanes, bisphenols, orthobisphenols, etc. can be used.

Furthermore, leucobase obtained by reducing a dye can also be used as a reducing agent. Furthermore, it is also possible to use a combination of two or more of the above-mentioned reducing agents. When using a secondary color developing agent, it is desirable to use a coupler that reacts with these oxidation products to form a light-absorbing compound.

Specific examples of reducing agents whose generated oxidants become light-absorbing compounds include hydroquinone, hydroquinone monomethyl ether, 2,4-dimethyl-6-t-butylphenol, catechol, dichlorocatechol, 2-methylcatechol, Methyl gallate, ethyl gallate, propyl gallate, 0-aminophenol, 3,5-dimethyl-2-aminophenol, p-aminophenol, p
-amino-0-methylphenol, m-dimethylaminophenol, m-diethylaminophenol, 2゜6-
Dicyclohexyl-4-methylphenol, l-naphthol, 2-methyl-1-naphthol, 2°4-dichloro-1-naphthol, 1,1-di-2-naphthol, 2.
27-methylenebis(4-methyl-6-t-butylphenol), 2,2'-methylenebis(4-ethyl-6-
t-butylphenol), 2,2'-butylidene bis(
4-methyl-6-t-butylphenol), 4-4'-
Butylidenebis(3-methyl-6-t-butylphenol), 4,4'-methylenebis(2,6-di-t-butylphenol), 1.1.3-)lis(2-methyl-4
-Hydroxy-5-t-butylphenol)butane, 4
, 4'thiobis(3-methyl-6-t-butylphenol), 2,4-bis(ethylthio)-6-(4-hydroxy-3.5-di-t-butylanilino)-1,3°5-triazine, 2 ,4-bis(octylthio)-6-
(4-hydroxy-3,5-di-t-butylanilino)
1,3.5-triazine, 2,6-dichloro-4-benzenesulfonamidophenol, 2-chloro-4-benzenesulfonamidophenol, 2,6-dipromo4
-Benzenesulfonamidophenol, thioindoxyl, indoxyl, 1°3-dimethylpyrogallol, 4
-methoxynaphthol, 4-ethoxynaphthol, 2-
Cyanoacetylcoumarone, N,N-dimethylphenylenediamine, N,N-diethylphenylenediamine
N/, N/diethyl-3-methylphenylenediamine, and the like.

In addition, when a secondary color developing agent (e.g., phenylenediamine type, p-aminophenol type) is used, examples of the coupler include l-hydroxy-N-butyl-
2-Natsutamide, benzoylacetone, benzoylacetanilide, 0-methoxybenzoylaceto-〇-methquinanilide, dibenzoylmethane, 2-chloro-ninaphthol, 2゜6-dipromo-1,5-naphthalenediol, 3-methyl-1-phenyl Examples include pyrazolone.

The light transmission control layer of the photosensitive element should be able to change the amount of light transmitted in the absorption wavelength range of the photopolymerization initiator contained in the polymerization layer of the polymerization element. and/or light may be absorbed due to the image of the oxidized form of the reducing agent, and similarly, light may be absorbed due to the image of the reaction product of the auxiliary material contained in the layer. One that is in a state where it absorbs light and disappears after the reaction is also good.

The light-absorbing compound may or may not fall into the category of a dye (as long as it can substantially desensitize the sensitivity of the photopolymerization initiator. For example, a violet When using external absorption, absorption in the visible region is not a problem.

Specific examples of the combination of a light-absorbing compound and a photopolymerization initiator include 4,4'-butylidene bis(3-methyl-6-t~butylphenol), 4,4' as a reducing agent;
When methylenebis(2,6-di-t-butylphenol) or the like is used, a photopolymerization initiator sensitive to 380 to 390 nm, such as 2-chlorothioxanthone, 2
-Methylthioxanthone, 2゜4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2. 4.
6-Trimethylbenzoylphenylphosphine oxide, benzyl, etc. can be used.

Also, 2,4-bis(ethylthio)-6-(4-hydroxy-3,5-di-t-butylanilino)-1°3.5
-triazine, 2,4-bis(octylthio)6-(4
-hydroxy-3,5-di-t-butylanilino)-1
, 3, 5-) Those that form a cyan dye with riazine or a secondary color developing agent have a color of 300 to 34 in addition to the visible area.
Photoinitiators sensitive to 0 nm, such as ■-phenyl-2-hydroxy-2-methylpropan-1-one, l-hydroxycyclohexyl phenyl ketone, benzoin dimethyl ether, benzophenone, 4-benzoyl-4'-methyldiphenyl Sulfide etc. can be used.

A preferred blending ratio of the above components in the light transmission control layer of the photosensitive element of the present invention is as follows.

Preferably 0 silver halide per mol of organic silver salt
．． 001 mol to 2 mol, more preferably 0.05 mol to
It is desirable to contain 0.4 mol. In addition, organic silver salt 1
The reducing agent is preferably 0.2 to 3 moles per mole,
More preferably, the content is 0.7 mol to 1.3 mol.

In addition, anti-gabbing agents, anti-photodiscoloration agents,
A solid solvent, surfactant, antistatic agent, etc. may be added.

For the polymerization layer, preferably 0.1 parts by weight to 3 parts by weight of a photopolymerization initiator per 100 parts by weight of the polymerizable monomer,
It is more preferable to use 0.5 parts by weight to 10 parts by weight, and the content of the heat-diffusible dye is as follows: Preferably it is 2.5 to 100 parts by weight, more preferably 5 to 50 parts by weight.

Further, the polymer layer in the present invention may have a two-layer structure including a color material layer comprising a heat-diffusible dye and a binder, and a polymer layer comprising a polymerizable monomer and a photopolymerization initiator.

The outline of each step included in the method of the present invention will be explained below with reference to the drawings.

FIG. 2 is a schematic diagram showing one embodiment of the image forming method of the present invention. In the figure, (a) imagewise exposure is performed on the photosensitive layer element 2 of the medium 1 (image forming medium A) on which a first color image is to be formed, and the photosensitive silver halide 8 in the light transmission control layer 6 is exposed to light in an imagewise manner. A latent image 11 is formed. [Figure 2 (I)] Next, a method for forming a multicolor image using a photoreceptor having three different color tones as described above is shown in Figures 2 (I) to (r).
V).

First, on the photoreceptor (A) on which the first color image is to be formed,
Step (n) of performing imagewise exposure (hr) to form a latent image 7 on the photosensitive silver halide 4 in the light transmission control layer 2; (n) heating the photoreceptor (A) (Δ); A step of causing an oxidation-reduction reaction using the latent image nucleus 7 of S silver halide as a catalyst to generate a silver image and an oxidized product 9 of a reducing agent to form contrasts 4-a and 4-b consisting of a difference in transmittance. (4-a is the light absorption part)
, (III) Irradiating light in the absorption wavelength range of the photopolymerization initiator contained in the polymerization layer of the photoreceptor (A) from the light transmission control layer side 2 from the light transmission control layer side (hr). The polymerized layer 3 is polymerized according to the absorption contrast image of (3).
-a, 3-b) (3-a is the unpolymerized part, 3
-b is the polymerization part), (IV) The photoreceptor (A) and the image receiving paper 10 are laminated and heated (Δ) to transfer the thermally diffusible dye (A-Dye) contained in the polymerization layer 3 to ( A step of forming a color image made of a heat-diffusible dye (A-Dye) on the image receiving paper 10 is performed in accordance with the polymerized image (3-a, 3-b) formed in step I[[).

At this time, the degree of polymerization in the polymerized area becomes high and the Tg increases, so the inherent dye is diffused. However, an image made of heat-diffusible dye is not formed on the receiving paper, and the dye in the unpolymerized area is diffused. Then, a color image is formed in that area.

These steps (I) to (rV) are performed on the photoreceptor (B), the photoreceptor (
The same procedure was applied to C), and the diffusible dye (
A multicolor image consisting of A-Dye, B-Dye, and C-Dye is formed.

As the light source used in the above steps (I) and (m), for example, sunlight, a tungsten lamp, a mercury lamp, a halogen lamp, a xenon lamp, a fluorescent lamp, an LED, a laser beam, etc. can be used, and the wavelength of the light used in these processes is the same. may be different. In addition, even if light of the same wavelength is used in steps (I) and (III), since silver halide usually has a sufficiently higher photosensitivity than the photoinitiator, photopolymerization does not occur in the above steps. A sufficient latent image can be written with light of moderate intensity. A sensitizing dye may be added at the time of forming the photosensitive layer depending on the color distribution of each light source.

The temperature in step (n) is 608C to 180C, preferably 70 to 150C. Examples of the heating method include a planar heating element, a heat roller, dielectric heating, and a method in which the base material 8 is made into an energized heat generating layer or an energized heat generating layer is provided below the base material 8 and heated by applying electricity.

Furthermore, in the step (I[[) above, a means for heating the photoreceptor during exposure may be used. This may be done by newly heating or by using residual heat from the step (n) above.

Next, in the process of thermal diffusion transfer in color image formation, as shown in FIG.
Stack them and heat them appropriately. Thermal diffusive substance A-Dye exists in the polymerized layer 3, and the thermal diffusible substance A-Dye corresponding to the polymerized portion 3-b in the polymerized layer 3 is the thermal diffusible substance A-Dye corresponding to the unpolymerized portion 3-a. Compared to the chemical substance A-Dye, its thermal diffusivity is suppressed in the polymerized layer 3, so that by the above heating,
The thermally diffusible substance A-D·ye in the unpolymerized portion 3-a is selectively diffused and transferred.

In addition, in FIG. 2 (IV), after removing the light transmission control layer 2, the polymer layer 3 and the image receiving paper 10 are directly laminated.
It is also possible to perform thermal transfer with the light transmission control layer 2 provided. When removing the light transmission control layer 2, the light transmission control layer 2
It is a matter of course that the binder used in this step should be one that can be easily peeled off from the polymer layer 3.

The diffusivity of the thermally diffusive substance A-Dye in the polymerization part 3-b is suppressed by polymerization of the polymerizable monomer or by crosslinking of the polyfunctional polymerizable monomer when it is contained. This is because even if the polymerized portion 3-B is heated, the molecular restraint of the polymer is relaxed and inhibits the diffusion of the thermally diffusible substance.

The image-receiving layer of the image-receiving paper 10 used in this process is not particularly limited as long as the heat-diffusible substance can be well diffused and transferred and a good image can be formed, such as polyester resin, polycarbonate resin, polyacetic acid resin, etc. Various materials can be used, such as vinyl resin, polyurethane resin, polyamide resin, polycaprolactam resin, and polyvinyl chloride resin.

The heating temperature in this process is preferably 80 to 250°C, preferably 80 to 250°C, although the suitable value varies depending on various conditions such as the type of thermally diffusive substance and the degree of polymerization of the polymer.
It is 0-200°C.

After the above process, if the photoreceptor is removed by peeling or the like, an image consisting of the transferred dye or the dye developed in the image-receiving layer can be obtained in the image-receiving layer, as shown in FIG. 2 (IV). Can be done. This image is an image with excellent contrast, and has excellent brightness and chroma.

〔Example〕

(Preparation of photoreceptor A) Yellow coating liquid The above composition was sufficiently dissolved and mixed using an ultrasonic disperser,
A yellow coating liquid was obtained.

A polymer layer was applied onto a 22 μm thick polyester film anchored with a yellow coating solution so that the dry film thickness was 5 to 6 μm.

Emulsion (I) (Preparation of Photoreceptor B) Magenta Coating Solution The above composition was sufficiently dissolved and dispersed using a paint shaker to obtain an emulsion for a light transmission control layer.

A light transmission control layer was coated on the polymer layer for yellow so that the dry film thickness was 10 μm to obtain a photoreceptor for yellow (A).

The above composition was sufficiently dissolved using an ultrasonic disperser to prepare a magenta coating liquid.

Next, a magenta coating liquid was applied in the same manner as the yellow photoreceptor to obtain a polymerized layer. Further, emulsion (I) was applied thereon to a dry film thickness of 10 μm to form a magenta photoreceptor (B).
) was obtained.

(Preparation of photoreceptor C) Cyan coating liquid The above composition was sufficiently dissolved using an ultrasonic disperser to prepare a cyan coating liquid.

A cyan coating solution was applied in the same manner as the yellow photoreceptor to obtain a polymerized layer. Furthermore, emulsion (I) is applied on top of this to a dry film thickness of 1
A cyan photoreceptor (C) was obtained by coating the film to a thickness of 0 μm.

(Image formation) A three-color separation lithium film prepared for printing was laminated on the light transmission control layer of the yellow photoreceptor (A), and image exposure was performed by irradiating it for 0.5 seconds using a fluorescent lamp with a power consumption of 15 W. I did it. Next, it was heated at 119° (:,, 10 seconds), and a silver image was generated on the light irradiation area. Next, a fluorescent lamp with a power consumption of 15 W and a fluorescence peak at 340 nm was heated at 40
It was irradiated for sec.

Next, the light transmission control layer was peeled off, and the image receiving paper on which the image receiving layer had been provided in advance was laminated with the yellow polymer layer.
Heating under EC conditions, the image-receiving paper side has a brightness corresponding to image exposure.
A yellow image with excellent saturation was formed.

Next, the magenta photoreceptor (B) was subjected to imagewise exposure under the same conditions as in the case of yellow. When heated under the conditions of 119°C and 1 osec, a silver image was formed in the image-exposed area. Next 3
A fluorescent lamp with a power consumption of 10 W and having a fluorescence peak at 80 nm was irradiated for 30 seconds from a distance of 1 cm.

The light transmission control layer was peeled off, and the image receiving paper on which the yellow image was formed and the magenta layer were laminated and heated at 100°C.

When heated for 10 seconds, a magenta image with excellent brightness and chroma corresponding to image exposure was formed on the image receiving paper.

Next, the light transmission control layer of the cyan photoreceptor (C) was subjected to imagewise exposure under the same conditions as for the yellow photoreceptor.

Next, when heated at 119°C for 1 osec,
A silver image was formed in the image-exposed area. Next, a fluorescent lamp with a power consumption of 10 W and having a fluorescence peak at 450 nm was irradiated for 30 seconds from a distance of I cm.

The light transmission control layer was peeled off, and the image receiving paper on which yellow and magenta images were formed was laminated with the cyan polymer layer, and heated at 100°C.
, 10 seconds, a cyan image with excellent brightness and chroma corresponding to image exposure was formed on the image-receiving paper.

As described above, by using the yellow photoreceptor (A), magenta photoreceptor (B), and cyan photoreceptor (C) and the image forming method of the present invention, a multicolor image with excellent brightness and chroma can be formed on image receiving paper. is formed by dry processing with high sensitivity and high resolution.

〔Effect of the invention〕

As explained above, by forming an image using the multicolor image forming method of the present invention, a multicolor image with excellent brightness and saturation can be obtained with high sensitivity and high resolution, and moreover, by dry processing. .

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a photoreceptor suitably used in the present invention, and FIG. 2 is a schematic sectional view showing aspects of each process of the multicolor image forming method of the present invention. 1... Photoreceptor, 2... Light transmission control layer, 3... Polymerization layer, 4... Silver halide, 5... Reducing agent, 6...
Thermodiffusible dye, 7... Latent image, 8... Base material, 9...
Oxidized product, 10... Receiving paper No. 1 Figure 2 Swordsmith)

Claims (1)

[Scope of Claims] A multicolor image forming method in which a multicolor image is obtained by sequentially recording a plurality of monochrome images of different color tones, which comprises at least a polymerizable monomer, a photopolymerization initiator, and thermal diffusion for forming a monochrome image. (I) Image exposure step (II) Heating step (III) Full-surface exposure step (IV) It is characterized by forming a multicolor image by sequentially performing a process of laminating with image receiving paper and thermally transferring it to form a monochromatic image made of heat diffusible dye on the image receiving paper on photoreceptors of different tones. A multicolor image forming method.