JPH04296757A - Image forming method using microcapsule - Google Patents

Abstract

PURPOSE:To provide the image forming method using a novel monosheet type material capable of obtaining a color image on a photosensitive material. CONSTITUTION:A layer contg. a bleachable dye and photosensitive microcapsules contg. at least silver halide, a reducing agent and a polymerizable compd. is formed on a substrate to produce a photosensitive material. This photosensitive material is imagewise exposed, developed by heaitng and pressed. By this pressing, the microcapsules in the unexposed or exposed part are destructed to bleach the dye in the part and a negative or positive image is obtd.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming method using a monosheet-type photosensitive material capable of producing a color image on the photosensitive material.

0002

[Prior Art] A photosensitive material has a photosensitive layer containing silver halide, a reducing agent, and a polymerizable compound on a support. A latent image is formed on the silver halide, and a polymerizable compound is polymerized in response to the latent image. It can be used in image forming methods. An example of this image forming method is published in Japanese Patent Publication No. 45-11149.
No. 47-20741, No. 49-10697, JP-A No. 57-138632, No. 57-142638,
No. 57-176033, No. 57-211146, No. 58-107529, No. 58-121031, No. 5
No. 8-169143. In these methods, when exposed silver halide is developed using a developer, coexisting polymerizable compounds (e.g., vinyl compounds) are polymerized to form a polymeric compound in an image-wise manner. . Therefore, the above method requires a development process using a liquid, and the process requires a relatively long time.

[0003] As an improvement of the above method, Japanese Patent Laid-Open No. 61-69
No. 062, No. 61-73145, No. 61-18364
No. 0, No. 61-188535, No. 61-228441
Each publication describes a method by which a polymer compound can be formed by dry processing. The above method uses a recording material (photosensitive material) in which a support carries a photosensitive layer consisting of a photosensitive silver salt (silver halide), a reducing agent, a crosslinking compound (polymerizable compound), and a binder. be. The above image forming method is a method of polymerizing the polymerizable compound in the area where the silver halide latent image is formed.

Furthermore, a method of polymerizing a polymerizable compound in areas where a silver halide latent image is not formed was disclosed in JP-A-61
-183641, 61-260241, 62-
No. 70836, No. 62-81635, JP-A-2-14
No. 1756, No. 2-141757, No. 2-20725
No. 4, No. 2-262662.

As one embodiment of a photosensitive material that can be used in the above-described image forming method, a photosensitive material having a structure in which silver halide and a polymerizable compound are housed in microcapsules is disclosed in JP-A-61-275742. Are listed. A photosensitive material using the above-mentioned microcapsules (hereinafter referred to as photosensitive microcapsules) has the advantage that clear images, particularly images with excellent sharpness, can be obtained. On the other hand, the development and polymerization reactions in the above image forming method are
Proceeds smoothly under alkaline conditions. For this reason, it is preferable to include a base or a base precursor as an image formation accelerator in the photosensitive layer of the photosensitive material. Regarding a photosensitive material characterized in that the photosensitive layer contains a base or a base precursor, Japanese Patent Application Laid-Open No. 62-264041
It is stated in the specification of the issue.

When a base or base precursor is added to a photosensitive material using the photosensitive microcapsules described above, accommodating the base or base precursor in the photosensitive microcapsules improves the image formation promoting function of the base or base precursor. This is preferable in this respect. Japanese Patent Publication No. 64-322
Publication No. 51, Japanese Unexamined Patent Publication No. 1-263641, Japanese Patent Application No. 1-1
No. 82245, Japanese Patent Application No. 1-160148, and the specification thereof describe a photosensitive material using a photosensitive microcapsule characterized by containing a base or a base precursor therein.

[0007] As an image forming method using a photosensitive material using these photosensitive microcapsules, a general method is to transfer an image on the photosensitive material to an image receiving material. On the other hand, in the transfer-type image forming method, there are problems such as disposal of the photosensitive material after transfer, so it has been desired to form a monosheet. JP-A-62-209444 describes a monosheet-type photosensitive material in which a photosensitive material and an image-receiving material are integrated. In this photosensitive material, an image is obtained by releasing a coloring material by destroying the microcapsules. However, this mono-sheet type photosensitive material has a problem in that if the photosensitive material is scratched during handling, stains occur in the white background of the image, resulting in images with poor sharpness.

[0008] Furthermore, regarding a monosheet type photosensitive material using a decoloring reaction rather than a coloring reaction, Japanese Patent Application Laid-Open No. 120-1983
143, this example uses a method in which the bleaching sheet and the photosensitive material are brought into contact and heated to bleach the dye in the unexposed areas, but the dye in the exposed areas also moves during heating. There was a problem in that the contrast was lowered due to bleaching and the lowering of the density in high density areas.

[0009]

[Problems to be Solved by the Invention] An object of the present invention is to provide an image forming method that provides an image with high contrast and excellent sharpness using a monosheet-type photosensitive material that utilizes a decoloring reaction. There is.

0010

[Means for Solving the Problems] The above-mentioned problems have been achieved by the following monosheet-type photosensitive materials and image forming methods using them. First, microcapsules containing at least silver halide, a reducing agent, and a polymerizable compound are created. Next, a photosensitive material containing at least the microcapsules and a bleachable dye on a support is prepared.

Next, this photosensitive material is imagewise exposed, developed, and if necessary, the entire surface is heated or exposed to light to harden the polymerizable compound corresponding to the exposed or unexposed regions. Furthermore, by pressurizing the photosensitive material, the polymerizable compound corresponding to the unexposed area or the exposed area and the bleaching agent are released from the microcapsules.
An image is obtained by decolorizing the bleachable dye contained in the dye layer near the microcapsules.

That is, the photosensitive material of the present invention uses a bleachable dye and a bleaching agent in combination. For example, JP-A-6
Dyes such as azo dyes and anthraquinone dyes described in Publication No. 1-120143 react with reducing agents or oxidizing agents and are bleached into substantially colorless compounds. It is used as a bleachable dye and is also described as a bleaching agent in JP-A-61-120143. As the reducing agent, for example, a tin (II) compound such as tin chloride or tin sulfate, or a boron compound such as dimethylamine borane, etc. can be used, and as the oxidizing agent, for example, a peroxo acid such as peroxonitric acid and its salts can be used.

It is also possible to use a coloring dye obtained from a leuco dye and a color developer as a bleachable dye, and to use a polymerizable compound as the bleaching agent. In general, reducing agents and oxidizing agents tend to deteriorate the photosensitivity or developability of silver halide, but the mono-sheet type photosensitive material of the present invention uses a polymerizable compound as a bleaching agent that has almost no adverse effect on silver halide. In this case, the bleachable dye is preferably a coloring dye obtained from a leuco dye and a color developer. The following explanation will focus on this system.

The leuco dye is not particularly limited, and various substances including known substances can be used. Regarding known leuco dyes, see Moriga and Yoshida, “Dye and Medicine” 9,
p. 84 (Chemical Products Industry Association, 1964); "New Edition Dye Handbook" p. 242 (Maruzen, 1970); R. Garner “R.
eports on the Progress of
Appl. Chem. '56, 199 pages (1971
); "Dye and Drugs" p. 19,230 (Chemical Products Industry Association,
1974) etc. The above-mentioned leuco dyes are compounds that generally develop color upon contact with an acidic color developer, and it is preferable to use such leuco dyes in the light-sensitive material of the present invention.

[0015] Leuco pigments can be structurally classified into several types. Systems preferably used in the light-sensitive material of the present invention include diarylphthalide-based, fluoran-based, indolyl phthalide-based, acyleucoazine-based, leucouramine-based, spiropyran-based, rhodamine lactam-based, triarylmethane-based, and chromene. Examples include systems. Typical specific examples of leuco dyes that can be used in the light-sensitive material of the present invention will be classified by structure, and then their structural formulas will be shown. Moreover, the hue of each compound is shown in parentheses.

[0016]

[Chemical formula 1]

[0017]

[Case 2]

[0018]

[Chemical formula 3]

[0019]

[C4]

[0020]

[C5]

[0021]

[C6]

[0022]

[C7]

[0023]

[Chemical formula 8]

[0024]

[Chemical formula 9]

[0025]

[Chemical formula 10]

[0026]

[Chemical formula 11]

[0027]

[Chemical formula 12]

[0028]

[Chemical formula 13]

[0029]

[Chemical formula 14]

The above specific examples are some of the leuco dyes, and the leuco dyes used in the present invention are not limited to these. In addition, even when leuco dyes are used alone,
May be used in combination. Furthermore, when multiple leuco dyes are used, they are combined with at least three types of silver halides (silver halide emulsions will be described later) that are sensitive to different spectral regions, so that the leuco dyes correspond to the respective emulsions. It can also be used to create full-color images. In this case, it is necessary to match one dye to a capsule in one photosensitive area, but this can be done by making the three colors separate layers, or by attaching dye oil droplets around the capsule using the coacervate method. Examples include methods.

In the photographic material of the present invention, the leuco dye is preferably used in an amount of 0.5 to 50% by weight, more preferably 2 to 20% by weight, based on the polymerizable compound.

The light-sensitive material of the present invention is used by developing a color when a leuco dye is coated on a support. In the above-mentioned coloring method, an acidic color developer is coated or contained on a support, and a leuco dye is coated thereon to develop color on the support surface to form a bleachable dye layer. Alternatively, a bleachable dye layer may be formed by coating a liquid containing a leuco dye and an acidic color developer on a support.

Examples of the acidic color developer include acidic clay color developer (clay), phenol-formaldehyde resin (
e.g. p-phenylphenol-formaldehyde resin), metal salts of salicylic acids (e.g. zinc 3,5-di-α-methylbenzylsalicylate), phenol-salicylic acid-formaldehyde resin (e.g. p-octylphenol-zinc salicylate-formaldehyde) resin), zinc rhodan, zinc xanthate, etc. are preferred. Among the above-mentioned acidic color developers, oil-soluble zinc salts of salicylic acid are described in US Pat. No. 3,864,146, US Pat.

Further, in the present invention, a polymerizable compound is mainly used as a bleaching agent, which will be explained below. Polymerizable compounds used in photosensitive materials generally have addition polymerizability or ring-opening polymerizability. Compounds with addition polymerizability include compounds with ethylenically unsaturated groups, and compounds with ring-opening polymerizability include compounds with epoxy groups, but compounds with ethylenically unsaturated groups have polymerizability and bleaching properties. It is particularly preferable from this point of view.

Compounds having ethylenically unsaturated groups that can be used in photosensitive materials include acrylic acid and its salts, acrylic esters, acrylamides, methacrylic acid and its salts, methacrylic esters, and methacrylamides. , maleic anhydride, maleic esters, itaconic esters, styrenes, vinyl ethers, vinyl esters, N-vinyl heterocycles, allyl ethers, allyl esters, and derivatives thereof.

Specific examples of preferred polymerizable compounds that can be used in photosensitive materials include n-butyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, benzyl acrylate, furfuryl acrylate, and ethoxyethoxyethyl esters. Acrylate, tricyclodecanyloxyacrylate, nonylphenyloxyethyl acrylate, 1,3-dioxolane acrylate, hexanediol diacrylate, butanediol diacrylate, neopentyl glycol diacrylate, tricyclodecane dimethylol diacrylate, trimethylolpropane triacrylate acrylate, pentaerythritol tetraacrylate,

Dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, polyoxyethylated bisphenol A diacrylate,
2-(2-hydroxy-1,1-dimethylethyl)-5
-Hydroxymethyl-5-ethyl-1,3-dioxane diacrylate, 2-(2-hydroxy-1,1-dimethylethyl)-5,5-dihydroxymethyl-1,3-
Examples include dioxane triacrylate, triacrylate of propylene oxide adduct of trimethylolpropane, hexaacrylate of caprolactone adduct of dipentaerythritol, polyacrylate of hydroxypolyether, polyester acrylate, and polyurethane acrylate.

Other specific examples of methacrylic acid esters include methyl methacrylate, butyl methacrylate, ethylene glycol dimethacrylate, butanediol dimethacrylate, neopentyl glycol dimethacrylate, trimethylolpropane trimethacrylate, pentaerythritol trimethacrylate,
Examples include pentaerythritol tetramethacrylate and polyoxyalkylenated bisphenol A dimethacrylate.

The above polymerizable compounds may be used alone or in combination of two or more. For photosensitive materials containing two or more types of polymerizable compounds, please refer to JP-A No. 62-210445.
There is a description in the bulletin. In addition, a substance in which a polymerizable functional group such as a vinyl group or a vinylidene group is introduced into the chemical structure of the above-mentioned reducing agent can also be used as a polymerizable compound. The silver halide, reducing agent, and microcapsules used in the photosensitive material of the present invention will be explained below in order. In the light-sensitive material of the present invention, any grains of silver chloride, silver bromide, silver iodide, silver chlorobromide, silver chloroiodide, and silver iodobromide can be used as silver halide.

The silver halide grains in the photographic emulsion may have regular crystals such as cubic, octahedral, dodecahedral, or tetradecahedral, or irregular crystal systems such as spherical or plate-like. It may have crystal defects such as twin planes, or a composite form thereof. The grain size of silver halide is approximately 0
．． Even fine particles of 0.01 micron or less have a projected area diameter of approximately 10
Large size particles down to microns may be used, and polydisperse emulsions may also be used, as disclosed in U.S. Pat.
55,394 and British Patent No. 1,413,748.

Tabular grains having an aspect ratio of about 5 or more can also be used in the present invention. Tabular grains are described by Gutoff, Photographic Science and Engineering.
hic Science and Engineering
ng), Vol. 14, pp. 248-257 (1970);
U.S. Patent Nos. 4,434,226 and 4,414,31
No. 0, No. 4,433,048, No. 4,439,520
and British Patent No. 2,112,157.

The crystal structure may be uniform, the inside and outside may have different halogen compositions, or it may have a layered structure. Further, silver halides having different compositions may be joined by epitaxial joining,
Further, it may be bonded with a compound other than silver halide, such as silver rhodan or lead oxide. In addition, halogen composition,
Two or more types of silver halide grains having different crystal habits, grain sizes, etc. can also be used together.

Silver halide photographic emulsions that can be used in the present invention include, for example, Research Disclosure (RD) No.
．． 17643 (December 1978), pp. 22-23,
“I. Emulsion preparation
tion and types)” and the same No.
18716 (November 1979), p. 648, etc.

The silver halide emulsion used is usually one that has been subjected to physical ripening, chemical ripening and spectral sensitization. Additives used in such processes are listed in Research Disclosure No. 17643 and the same No. 18716
The relevant sections are summarized in the table below. Known photographic additives that can be used in the present invention are also described in the above two Research Disclosures, and the relevant descriptions are shown in the table below.

Additive type RD17
643RD18716
Chemical sensitizer page 23
Page 648 right column Sensitivity enhancer
Same as above Spectral sensitizer pages 23-24
Page 648 right column ~ Super sensitizer

Page 649 right column Antifogging agent
Pages 24-25 Page 649 Right column ~ and stabilizers

[0046] As the silver halide grains mentioned above, as in the photosensitive material described in JP-A No. 63-68830,
It is preferable to use silver halide grains with relatively low fog values. In order to uniformly contain silver halide in the microcapsules, it is preferable that a copolymer consisting of a hydrophilic repeating unit and a hydrophobic repeating unit is dissolved in the polymerization compound. For details, please refer to JP-A No. 6
There are descriptions in Japanese Patent Application No. 2-209450, No. 63-287844, and Japanese Patent Application No. 1-37782.

The reducing agent that can be used in the photographic material of the present invention has the function of reducing silver halide and/or the function of promoting (or inhibiting) polymerization of polymerizable compounds. There are various types of reducing agents having the above functions. The reducing agents include hydroquinones, catechols, p-aminophenols, p-phenylenediamines, 3-pyrazolidones, 3-aminopyrazoles, 4-amino-5-pyrazolones, 5-aminouracils, 4,5-dihydroxy-6-aminopyrimidines,
Reductones, aminoreductones, o- or p-sulfonamidophenols, o- or p-sulfonamidonaphthols, 2,4-disulfonamidophenols, 2,4-disulfonamidonaphthols, o- or p-acyl Aminophenols, 2-sulfonamide indanones, 4-sulfonamide-5-pyrazolones, 3-sulfonamide indoles, sulfonamide pyrazolobenzimidazoles, sulfonamide pyrazolotriazoles, α-sulfonamide ketones , hydrazines, etc.

[0048] Regarding various reducing agents having the above-mentioned functions, please refer to Japanese Patent Application Laid-open Nos. 61-183640 and 61-1885.
35, 61-228441, and JP-A-62-70836, 62-86354, and 6
No. 2-86355, No. 62-206540, No. 62-
No. 264041, No. 62-109437, No. 63-2
No. 54442, Japanese Patent Application No. 63-97379, No. 63-2
No. 96774, No. 63-296775, Patent Application No. 1-2
It is described in publications and specifications such as No. 7175, No. 1-54101, No. 1-91162, and No. 1-90087. (Including those described as developing agents or hydrazine derivatives) Also, regarding the above-mentioned reducing agents, T. Jmam
“The Theory of the P” by es
Photographic Process” 4th edition,
pp. 291-334 (1977) Research Disclosure Vol. 170, 1st June 1978
No. 7029 (pages 9-15), and the same magazine Vol. 1
76, No. 17643, December 1978 (22-31
There is also a description on page).

Furthermore, as in the photosensitive material described in JP-A-62-210446, a reducing agent precursor capable of releasing the reducing agent under heating conditions or in contact with a base may be used instead of the reducing agent. May be used. The reducing agents and reducing agent precursors described in each of the above-mentioned publications, specifications, and literature can also be effectively used in the photosensitive material used in this specification. Therefore, the "reducing agent" in this specification includes the reducing agents and reducing agent precursors described in each of the above-mentioned publications and literature.

Among these reducing agents, those having basicity that form salts with acids can also be used in the form of salts with appropriate acids.

These reducing agents may be used alone, or as described in the above specifications, two or more reducing agents may be used in combination. When two or more types of reducing agents are used together, the interaction of the reducing agents is, first, to promote the reduction of silver halide (and/or organic silver salt) through so-called superadditivity; , causing polymerization of the polymerizable compound via a redox reaction with other reducing agents coexisting with an oxidized form of the first reducing agent generated by reduction of silver halide (and/or organic silver salt); (or suppressing polymerization), etc. However, in actual use, the reactions described above can occur simultaneously, so it is difficult to specify which effect is occurring. Specific examples of the above reducing agent are shown below.

[0052]

[Chemical formula 15]

[0053]

[Chemical formula 16]

[0054]

[Chemical formula 17]

[0055]

[Chemical formula 18]

The amount of the reducing agent added can vary widely, but is generally from 0.1 to 1500 mol %, preferably from 10 to 300 mol %, based on the silver salt.

There are no particular limitations on the microcapsules of the present invention, and various known techniques can be applied. Examples include U.S. Pat.
No. 800458: Method utilizing coacervation of hydrophilic wall-forming materials described in each specification; US Pat. No. 32871
No. 54 and British Patent No. 990443, and interfacial polymerization methods described in Japanese Patent Publications No. 38-19574, No. 42-446, and No. 42-771; US Pat. No. 3418250 and No. 3660304. Methods by precipitation of polymers as described in the specification;

Method using the isocyanate-polyol wall material described in US Pat. No. 3,79669; Method using the isocyanate wall material described in US Pat. No. 3,914,511; US Pat. No. 4,001,140, US Pat.
No. 087376, No. 4089802 and No. 402
No. 5455, JP-A-62-209439, JP-A-64
There is a method using amino aldehyde resins described in No. 91131, JP-A No. 1-154140, and Japanese Patent Application No. 63-241635. Examples of amino aldehyde resins include urea-formaldehyde resin, urea-formaldehyde-resorcinol. resin, melamine-formaldehyde resin, acetoguanamine-formaldehyde resin,
Examples include benzoguanamine-formaldehyde resin.

In addition, in-situ methods by polymerization of monomers described in Japanese Patent Publication Nos. 36-9168 and 51-9079; polymerization dispersion cooling methods described in British Patent Nos. 927807 and 965074; ; US Patent No. 3,111,407 and British Patent No. 930
Examples include the spray drying method described in each specification of No. 422.

[0060] The method of microcapsulating oil droplets of a polymerizable compound is not limited to the above, but a method in which a core material is emulsified and then a polymer film is formed as the microcapsule wall is preferred. Regarding photosensitive materials using microcapsules having outer shells made of polyamide resin and/or polyester resin, Japanese Patent Application Laid-Open No. 62-209
No. 437 describes a photosensitive material using microcapsules having an outer shell made of polyurea resin and/or polyurethane resin, and JP-A-62-209438 describes a photosensitive material using microcapsules having an outer shell made of gelatin. Regarding materials, see JP-A No. 62-209440.

Regarding a photosensitive material using microcapsules having an outer shell made of epoxy resin, Japanese Patent Laid-Open No. 62-2
No. 09441 describes a photosensitive material using a microcapsule having a composite resin shell containing a polyamide resin and a polyurea resin, and JP-A-62-209447 discloses a photosensitive material having a composite resin shell containing a polyurethane resin and a polyester resin. Photosensitive materials using microcapsules are described in JP-A-62-209443.

[0062] In the present invention, it is particularly preferable to use melamine-formaldehyde resin, since it is possible to obtain highly dense capsules. Also, patent application No. 1-377
In the specification of No. 82, in order to obtain capsules with especially excellent wall density, melamine is added around a membrane made of a reaction product of a water-soluble polymer having a sulfinic acid group and a polymerizable compound having an ethylenically unsaturated group. - Microcapsules provided with a polymer wall of a high molecular compound such as formaldehyde resin have been disclosed and are preferred for the present invention.

When using aminoaldehyde microcapsules, it is preferable to keep the amount of residual aldehyde below a certain value, as in the photosensitive material described in JP-A-63-32535. The average particle diameter of the microcapsules is preferably 3 to 25 μm. It is preferable that the particle size distribution of the microcapsules is uniformly distributed over a certain value, as in the photosensitive material described in JP-A No. 63-5334. Further, the film thickness of the microcapsules is preferably within a certain value range with respect to the particle diameter, as in the photosensitive material described in JP-A-63-81336.

[0064] In order to accommodate silver halide in microcapsules, it is preferable that the average grain size of the silver halide grains described above be one-fifth or less of the average size of the microcapsules, and one-tenth of the average grain size of the microcapsules. It is more preferable to set it as follows. A uniform and smooth image can be obtained by setting the average particle size of the silver halide grains to one-fifth or less of the average size of the microcapsules.

When silver halide is contained in microcapsules, it is preferable that silver halide be present in the wall material constituting the outer shell of the microcapsules. A photosensitive material containing silver halide in the wall material of microcapsules is described in JP-A-62-169147. Other components that can be included in the photosensitive material of the present invention will be explained below. In the light-sensitive material of the present invention, it is preferable to use a base or a base precursor to accelerate development. As the base precursor that can be used in the photosensitive material of the present invention, base precursors of inorganic bases and organic bases (decarboxylation type, thermal decomposition type, reaction type, complex salt forming type, etc.) can be used.

Preferred base precursors include JP-A-59-180549, JP-A-59-180537, JP-A-59-195237, JP-A-61-32844, and JP-A-61.
-36743, 61-51140, 61-52
No. 638, No. 61-52639, No. 61-53631
No. 61-53634, No. 61-53635, No. 61-53636, No. 61-53637, No. 61-
No. 53638, No. 61-53639, No. 61-536
No. 40, No. 61-55644, No. 61-55645, No. 61-55646, No. 61-84640, No. 6
No. 1-107240, No. 61-219950, No. 61
-251840, 61-252544, 61-
No. 313431, No. 63-316740, No. 64-6
8746 and Japanese Patent Application No. 62-209138, salts of organic acids and bases that are decarboxylated by heating, and JP-A Nos. 59-157637 and 59-166.
Examples include compounds that eliminate bases upon heating as described in Japanese Patent No. 943 and No. 63-96159.

The base precursor of the present invention is 50
It is preferable to release the base at a temperature between 80°C and 200°C.
It is more preferable to release at a temperature of 180°C to 180°C. In the present invention, the base precursor is housed in microcapsules in order to make the heat development reaction proceed more rapidly. In that case, the following base precursor consisting of a salt of a carboxylic acid and an organic base having a solubility in water and a polymerizable compound at 25° C. of 1% or less is preferred.

(a) The base precursor is a salt of a carboxylic acid and an organic base, and the organic base has a partial structure corresponding to an atomic group obtained by removing one or two hydrogen atoms from an amidine represented by the following formula (1). It is a diacid to tetraacid base consisting of two to four of these and a structural group of the partial structure.

[0069]

[Chemical formula 19]

[In the above formula (1), R11, R12
, R13 and R14 each represent a monovalent group selected from the group consisting of a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an aralkyl group, an aryl group, and a heterocyclic residue (each group is may have one or more substituents), and R11, R12,
Any two groups selected from R13 and R14 may be bonded to each other to form a five- or six-membered nitrogen-containing heterocycle]

(b) A partial structure in which the base precursor is composed of a salt of a carboxylic acid and an organic base, and the organic base corresponds to an atomic group obtained by removing one or two hydrogen atoms from guanidine represented by the following formula (2). two to four pieces,
and a diacid to tetraacid base consisting of a linking group of the partial structure.

[0072]

[C20]

[In the above formula (2), R21, R22
, R23, R24 and R25 each represent a monovalent group selected from the group consisting of a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, an aralkyl group, an aryl group, and a heterocyclic residue (each (the group may have one or more substituents), and R21,
Any two groups selected from R22, R23, R24 and R25 may be bonded to each other to form a five- or six-membered nitrogen-containing heterocycle]

The above base precursors (a) and (b) are described in Japanese Patent Application Laid-Open No. 63-31670, respectively.
No. 64-68746. Specific examples of these base precursors are shown below, but are not limited thereto.

[0075]

[C21]

[0076]

[C22]

[0077]

[C23]

[0078]

[C24]

[0079]

[C25]

[0080]

[C26]

In the present invention, in order to accommodate the base precursor in microcapsules, a photosensitive composition in which the base precursor is directly solid-dispersed in a polymerizable compound may be used (see JP-A-64-32251, JP-A-1-
263641), it is particularly preferable to use a photosensitive composition in which a base precursor is dispersed in water and emulsified in a polymerizable compound. (Unexamined Japanese Patent Publication No. 63-2
No. 18964, Japanese Patent Application No. 1-182245, Japanese Patent Application No. 1-182245, Japanese Patent Application No. 1-182245,
160148 publications and specifications)

[0082]
Here, when dispersing the base precursor in water, it is preferable to use a nonionic or amphoteric water-soluble polymer. Examples of nonionic water-soluble polymers include polyvinyl alcohol, polyvinylpyrrolidone, polyacrylamide, polymethyl vinyl ether, polyacryloylmorpholine, polyhydroxyethyl acrylate, polyhydroxyethyl methacrylate-co-acrylamide, hydroxyethylcellulose, hydroxypropylcellulose. and methylcellulose.

[0083] Gelatin can also be mentioned as an amphoteric water-soluble polymer. The above-mentioned water-soluble polymer is preferably contained in a proportion of 0.1 to 100% by weight, more preferably 1 to 50% by weight, based on the base precursor. Further, the base precursor is preferably contained in an amount of 5 to 60% by weight, more preferably 10 to 50% by weight, based on the dispersion. Further, the base precursor is preferably contained in a proportion of 2 to 50% by weight, more preferably 5 to 30% by weight, based on the polymerizable compound.

In addition, in order to reduce the solubility of the base precursor in the polymerizable compound, polyethylene glycol, polypropylene glycol, benzoic acid amide, cyclohexyl urea, octyl alcohol, dodecyl alcohol, stearyl alcohol, stearamide, etc. are added to the polymerizable compound. -OH,
-SO2 NH2 , -CONH2 , -NHCONH
A compound having a hydrophilic group such as 2 can also be added.

The binders that can be used in the photosensitive material can be contained in the photosensitive layer alone or in combination. It is preferable to use a mainly hydrophilic binder. Typical hydrophilic binders are transparent or translucent hydrophilic binders, such as natural substances such as gelatin, gelatin derivatives, cellulose derivatives, starch, gum arabic, etc., and polyvinyl alcohol, polyvinylpyrrolidone, acrylamide polymers, etc. synthetic polymeric materials such as water-soluble polyvinyl compounds.

Other synthetic polymeric substances include dispersed vinyl compounds in the form of latexes, which increase the dimensional stability of photographic materials, among others. Incidentally, a photosensitive material using a binder is described in JP-A-61-69062. Furthermore, a photosensitive material using a binder together with microcapsules is described in JP-A-62-209525. In the present invention, an organic metal salt can also be used as an oxidizing agent together with photosensitive silver halide. Among such organic metal salts, organic silver salts are particularly preferably used.

Organic compounds that can be used to form the above organic silver salt oxidizing agent include those described in US Pat. No. 4,500,6
There are benzotriazoles, fatty acids and other compounds described in No. 26, columns 52-53. Also, JP-A-60-11
Silver salts of carboxylic acids having alkynyl groups such as silver phenylpropiolate described in JP-A No. 3235, and JP-A-61
Acetylene silver described in the publications No. 249044 and No. 64-57256 is also useful. Two or more types of organic silver salts may be used in combination.

The above organic silver salt is photosensitive silver halide 1
per mole, from 0.01 to 10 moles, preferably 0.01 to 10 moles.
0. 1 to 1 mol can be used in combination. The total coating amount of photosensitive silver halide and organic silver salt is suitably 1 mg to 10 g/m 2 in terms of silver.

The anti-smudge agent used in the photosensitive material is preferably a particulate material that is solid at room temperature. As a specific example,
Starch particles described in UK Patent No. 1,232,347, polymer fine powders described in US Pat. No. 3,625,736, etc., microcapsule particles containing no coloring agent described in UK Patent No. 1,235,991, etc., US Pat. No. 271
Inorganic particles such as cellulose fine powder described in No. 1375, talc, kaolin, bentonite, waxite, zinc oxide, titanium oxide, and alumina can be mentioned.

[0090] The average particle size of the above particles is preferably in the range of 3 to 50 μm in volume average diameter, and in the range of 5 to 4 μm.
A range of 0 μm is more preferable. As mentioned above, when the oil droplets of the polymerizable compound are in the form of microcapsules, it is more effective if the particles are larger than the microcapsules. Various image formation accelerators can be used in the photosensitive material.

[0091] Image formation promoters include: ■ Promotion of movement of base or base precursor; ■ Promotion of reaction between reducing agent and silver salt.
It has functions such as promoting the immobilization of dye-donating substances through polymerization, and from a physicochemical function, it interacts with the bases or base precursors, nucleophilic compounds, oils, thermal solvents, surfactants, silver or silver salts. It is classified into compounds with action, compounds with oxygen removal function, etc. However, these substance groups generally have multiple functions and usually have some of the above-mentioned promoting effects. For further details, see U.S. Pat. No. 4,678,739, columns 38-40;
It is described in publications and specifications such as JP-A-62-209443.

In a system for polymerizing a polymerizable compound in a portion of the light-sensitive material where a silver halide latent image is not formed,
A thermal or photopolymerization initiator can be used to initiate polymerization or to polymerize unpolymerized compounds after image transfer. Examples of thermal polymerization initiators include azo compounds, organic peroxides, inorganic peroxides, sulfinic acids, and the like. Details of these are described in pages 6 to 18 of "Addition Polymerization/Ring-Opening Polymerization" (Kyoritsu Shuppan, 1983), edited by the Society of Polymer Science and Technology, Editorial Committee of Polymer Experimental Science.

Examples of photopolymerization initiators include benzophenones, acetophenones, benzoins, and thioxanthone. Details of these are described in "Ultraviolet Curing System" (1989, General Technology Center), pages 63 to 147. Various surfactants can be used in photosensitive materials for the purposes of coating aids, improving peelability, improving slipperiness, preventing electrification, promoting development, and the like. Specific examples of surfactants are given in JP-A-62-1734.
No. 63, No. 62-183457, etc.

An antistatic agent can be used in the photosensitive material for the purpose of preventing static electricity. As an antistatic agent, Research Disclosure Magazine No. 17643, November 1978 (
(page 27) etc. A dye or pigment may be added to the photosensitive layer of the photosensitive material for the purpose of preventing halation or irradiation. JP-A-63-29748 describes a photosensitive material in which a white pigment is added to the photosensitive layer.

A dye having the property of being decolored by heating or light irradiation may be contained in the microcapsules of the photosensitive material. The dye having the property of being decolored by heating or light irradiation can function as a yellow filter in conventional silver salt photography. A photosensitive material using a dye having the property of being decolored by heating or light irradiation as described above is described in JP-A-63-974940.

When a solvent for a polymerizable compound is used in a photographic material, it is preferably used by encapsulating it in a microcapsule separate from the microcapsule containing the polymerizable compound. Regarding photosensitive materials using organic solvents that are miscible with polymerizable compounds encapsulated in microcapsules, Japanese Patent Laid-Open No. 6
There is a description in Publication No. 2-209524. A water-soluble vinyl polymer may be adsorbed onto the silver halide grains described above. A photosensitive material using a water-soluble vinyl polymer as described above is described in JP-A-62-91652.

In addition to those mentioned above, examples of optional components that can be included in the photosensitive layer and their usage can be found in the application specifications related to the above-mentioned series of photosensitive materials, and in Research Disclosure Magazine Vol. 170,
It is described in No. 17029, June 1978 (pages 9-15). Examples of layers that can be optionally provided on the photosensitive material include an image-receiving layer, a heating layer, an antistatic layer, an anti-curl layer, a peeling layer, a cover sheet or protective layer, an anti-halation layer (colored layer), etc. can.

[0098] Regarding photosensitive materials using a heating layer, see JP-A No. 61-294434, and about photosensitive materials provided with a cover sheet or protective layer, see JP-A No. 62-2.
No. 10447 discloses a photosensitive material provided with a colored layer as an antihalation layer, and Japanese Patent Application Laid-Open No. 63-101842.
They are described in the respective publications. Furthermore, examples of other auxiliary layers and their usage are also described in the applications relating to the above-mentioned series of light-sensitive materials.

Various antifoggants or photographic stabilizers can be used in the present invention. Examples include azoles and azaindenes described in RD17643 (1978) pages 24-25, and JP-A-59-16844.
Nitrogen-containing carboxylic acids and phosphoric acids described in No. 2, mercapto compounds and metal salts thereof described in JP-A-59-111636, acetylene compounds described in JP-A-62-87957, etc. are used. It will be done.

[0100] Various development stoppers can be used in the photosensitive material in order to always obtain a constant image regardless of the processing temperature and processing time during development. The development stopper referred to here is a compound that neutralizes the base or reacts with the base to lower the base temperature in the film and stop development, or interacts with silver and silver salts to inhibit development. It is a compound that Specific examples thereof include acid precursors that release acids when heated, electrophilic compounds that cause a substitution reaction of coexisting bases when heated, nitrogen-containing heterocyclic compounds, mercapto compounds, and precursors thereof.

Materials that can be used for the support include glass, paper, wood-free paper, baryta paper, coated paper, cast coated paper, synthetic paper, metals and their analogs, polyester, polyethylene, polypropylene, acetyl cellulose, and cellulose. Examples include films of ester, polyvinyl acetal, polystyrene, polycarbonate, polyethylene terephthalate, polyimide, etc., and papers laminated with resin materials and polymers such as polyethylene.

[0102] When a porous material such as paper is used as the support, it is preferable that the support has a certain degree of smoothness, as in the image-receiving material described in JP-A-62-209530. In addition, when using a transparent support,
There is a description in JP-A-62-209531. An image-receiving layer composed of a white pigment, a binder, and other additives may be provided on the support in order to increase the receptivity of the polymerizable compound.

At this time, the image-receiving layer is prepared by mixing an acidic color developer with the image-receiving layer material, and a leuco dye is applied thereon to form a bleachable dye layer, or a leuco dye is coated on the image-receiving layer. A dye layer that can be bleached may be formed by applying a solution containing an acidic color developer.

Examples of white pigments used in the image-receiving layer include inorganic white pigments such as oxides such as silicon oxide, titanium oxide, zinc oxide, magnesium oxide, and aluminum oxide, magnesium sulfate, barium sulfate, calcium sulfate, and magnesium carbonate. , barium carbonate, calcium carbonate,
Alkaline earth metal salts such as calcium silicate, magnesium hydroxide, magnesium phosphate, and magnesium hydrogen phosphate, as well as aluminum silicate, aluminum hydroxide, zinc sulfide, various clays, talc, kaolin, zeolite, acid clay, and activated clay. Examples include white clay and glass.

Examples of organic white pigments include polyethylene, polystyrene, benzoguanamine resin, urea-formalin resin, melamine-formalin resin, and polyamide resin. These white pigments may be used alone or in combination, but those with high oil absorption for polymerizable compounds are preferred.

Further, as the binder used in the image-receiving layer of the present invention, water-soluble polymers, polymer latexes, polymers soluble in organic solvents, etc. can be used. Examples of water-soluble polymers include cellulose derivatives such as carboxymethyl cellulose, hydroxyethyl cellulose, and methyl cellulose, proteins such as gelatin, phthalated gelatin, casein, and ovalbumin, starches such as dextrin and etherified starch, polyvinyl alcohol, and polyvinyl alcohol moieties. Synthetic polymers such as acetal, poly-N-vinylpyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyvinylimidazole, polyvinylpyrazole, polystyrene sulfonic acid,
Other examples include locust bean gum, pullulan, gum arabic, and sodium alginate.

Examples of the polymer latex include styrene-butadiene copolymer latex, methyl methacrylate-butadiene copolymer latex, polymer or copolymer latex of acrylic acid ester and/or methacrylic acid ester, and ethylene-vinyl acetate copolymer latex. Examples include polymer latex.

Examples of polymers soluble in organic solvents include polyester resins, polyurethane resins, polyvinyl chloride resins, and polyacrylonitrile resins. The above-mentioned binders can be used in combination of two or more types, and can also be used in combination in such a ratio that the two types of binders cause phase separation. An example of such usage is described in Japanese Patent Application Laid-open No. 1-154789.

[0109] The average particle size of the white pigment is 0.1 to 20
μ, preferably 0.1 to 10 μ, and the coating amount is 0.1 to 10 μ.
It ranges from 1 g to 60 g, preferably from 0.5 g to 30 g. The weight ratio of the white pigment to the binder is preferably in the range of 0.01 to 0.4 of the binder to 1 of the pigment, and is 0.0
The range of 3 to 0.3 is more preferable. In addition to the binder and the white pigment, the image-receiving layer can contain various additives as described below.

[0110] The image-receiving layer may contain a thermoplastic compound. When the image-receiving layer contains a thermoplastic compound, it is preferable that the image-receiving layer itself is constituted as an aggregate of thermoplastic compound fine particles. The image-receiving layer having the above structure has the advantage that it is easy to form a transferred image, and that a glossy image can be obtained by heating after image formation. The above thermoplastic compound is not particularly limited and can be arbitrarily selected from known plastic resins (plastics), waxes, and the like. However, the glass transition point of the thermoplastic resin and the melting point of the wax are preferably 200° C. or lower. Regarding the image-receiving material having an image-receiving layer containing thermoplastic compound fine particles as described above,
It is described in No. 2-280071 and No. 62-280739.

The image-receiving layer may contain a photopolymerization initiator or a thermal polymerization initiator. In the image formation of the present invention, an unpolymerized polymerizable compound is released as a dye bleaching substance. Therefore, a photopolymerization initiator or a thermal polymerization initiator can be added to the image-receiving layer for the purpose of smoothly proceeding with the curing process (fixing process) of the unpolymerized polymerizable compound. Further, regarding an image receiving material having an image receiving layer containing a photopolymerization initiator, see JP-A-62-161149, and regarding an image-receiving material having an image-receiving layer containing a thermal polymerization initiator, see JP-A-62-161149.
There are descriptions in JP-A-210444.

[0112] In the image forming method of the present invention, the photosensitive material is heated from the side of the support not coated with a photosensitive layer, either simultaneously with the imagewise exposure or after the imagewise exposure. A series of steps including the step of applying pressure to the photosensitive material and the step of pressurizing the photosensitive material will be described. Although various exposure means can be used as the exposure method in the imagewise exposure step, a latent image of silver halide is generally obtained by imagewise exposure to radiation including visible light. The type of light source and amount of exposure
It can be selected depending on the wavelength to which silver halide is sensitive (in the case of dye sensitization, the sensitized wavelength) and sensitivity.

Typical light sources include natural light, ultraviolet light, visible light, infrared light, fluorescent light, tungsten lamp, mercury lamp, halogen lamp, xenon flash lamp, laser light source (gas laser,
solid state lasers, chemical lasers, semiconductor lasers, etc.)
Examples include light emitting diodes, plasma arc tubes, FOTs, and the like. In special cases, high-energy ray sources such as X-rays, γ-rays, and electron beams can also be used.

[0114] The photosensitive material of the present invention, especially in the case of a full-color photosensitive material, is composed of microcapsules that are sensitive to multiple spectral regions, and therefore requires image exposure using multiple corresponding spectral lines. It is. Therefore, one type of the light source may be used or a combination of two or more types may be used. When choosing a light source,
In addition to choosing a light source that is suitable for the sensitive wavelength of the photosensitive material, the choice can also be made by taking into consideration whether image information is transmitted via electrical signals, the processing speed of the entire system, compactness, power consumption, etc.

[0115] When image information does not pass through electrical signals, for example, direct photography of landscapes or people, direct copying of original images,
In the case of exposure through a positive such as a reversal film, a camera, an exposure device for printing such as a printer or an enlarger, an exposure device of a copying machine, etc. can be used. In this case, the two-dimensional image can be exposed simultaneously in a so-called one shot, or can be scanned and exposed through a slit or the like. You can also enlarge or reduce the original image. In this case, the light source is usually not a monochromatic light source such as a laser, but a light source such as a tungsten lamp or a fluorescent lamp, or a combination of multiple monochromatic light sources.

[0116] When image information is recorded via electrical signals, a light emitting diode or various lasers may be used in combination as the image exposure device in accordance with the color sensitivity of the heat-developable color photosensitive material; Various devices known as image display devices (CRT, liquid crystal display, electroluminescent display, electrochromic display, plasma display, etc.) can also be used. In this case, the image information includes an image signal obtained from a video camera or an electronic still camera, a television signal typified by the Nippon Television Signal Standard (NTSC),
Image signals obtained by dividing an original image into many pixels using a scanner or the like, or image signals stored on recording materials such as magnetic tapes or disks can be used.

[0117] When exposing a color image, LEDs, lasers, fluorescent tubes, etc. are used in combination according to the color sensitivity of the photosensitive material, but it is also possible to use a combination of multiple types of the same type, or to use a combination of different types. It's okay. In the photographic field, the color sensitivity of photosensitive materials is R (red), G (green), and B (blue).
Usually, they are photosensitive, but in recent years they are often used in combination with UV, IR, etc., and the range of use of light sources is expanding. For example, the color sensitivity of a photosensitive material is (G, R, IR)
or (R, IR (short wave), IR (long wave)), (
UV (short wave), UV (medium liquid), UV (long wave)), (UV
, B, G) etc. are utilized. The light source may also be a combination of different types, such as a combination of two-color LEDs and a laser.

[0118] The above-mentioned arc tube or element may be used for scanning exposure using a single tube or element for each color, or an array may be used to increase the exposure speed. Arrays that can be used include LED arrays, liquid crystal shutter arrays, magneto-optic shutter arrays, and the like. The image display devices described above include those with color display such as a CRT and those with monochrome display, but a method may be adopted in which a monochrome display is combined with a filter and exposed several times. Existing two-dimensional image display devices may be used in a one-dimensional manner like FOT, or one screen may be divided into several parts and used in combination with scanning.

By the imagewise exposure step described above, a latent image is obtained on the silver halide contained in the microcapsules. The image forming method of the present invention includes a step of heating in order to thermally develop the photosensitive material simultaneously with or after the imagewise exposure. Preferably, thermal development is carried out by heating the surface of the support on which the photosensitive layer of the photosensitive material is not coated.

[0120] This heating means is disclosed in Japanese Patent Application Laid-Open No. 61-29
As in the photosensitive material described in Japanese Patent No. 4434, a heating layer may be provided on the surface of the support on which the photosensitive layer of the photosensitive material is not coated and heated. Furthermore, as described in JP-A-61-147244, a hot plate, an iron, or a heated roller is used, or as described in JP-A-62-144166, a photosensitive material is sandwiched between a heated roller and a belt. A heating method may also be used.

That is, the photosensitive material may be brought into contact with a heating element having a surface area larger than that of the photosensitive material, and the entire surface may be heated at the same time, or the entire surface may be heated simultaneously by contacting the photosensitive material with a heating element having a surface area larger than that of the photosensitive material.
The entire surface may be heated over time by scanning with a heated roller, heated drum, etc.). In addition to the above heating method in which the heating element and the photosensitive material are brought into direct contact, it is also possible to heat the photosensitive material in a non-contact manner by applying electromagnetic waves, infrared rays, hot air, etc. to the photosensitive material.

[0122] Thermal development by heating may be carried out simultaneously with or after imagewise exposure, but heating is preferably carried out after 0.1 second or more has elapsed after imagewise exposure. The heating temperature is generally 60°C to 250°C, preferably 80°C to 180°C.
The heating time is between 0.1 seconds and 5 seconds.

The photosensitive material can be thermally developed as described above to polymerize the polymerizable compound in the areas where the silver halide latent image is formed or the areas where the silver halide latent image is not formed. In addition, if a polymerization inhibitor is generated in the area where a latent image of silver halide is formed by reaction with a reducing agent, the polymerization inhibitor may be added to the photosensitive layer in advance, preferably in microcapsules, to initiate thermal or photopolymerization. It is also possible to decompose the agent by heating or irradiating it with light, uniformly generating radicals, and polymerizing the polymerizable compound in the portion where the silver halide latent image is not formed. In this case, in addition to the imagewise exposure step and heat development step described above, a step of heating or exposing the entire surface is required if necessary, but the method is the same as the imagewise exposure step or the heat development step.

[0124] According to the image forming method of the present invention, a polymer image is obtained on the photosensitive layer, and in the step of pressurizing this, unpolymerized polymerizable compounds are released onto the bleachable dye layer to obtain a color image. be able to. As this pressurizing method, a conventionally known method can be used.

For example, the photosensitive material may be sandwiched between press plates such as a presser, or pressure may be applied while conveying using a pressure roller such as a nip roll. Pressure may be applied intermittently using a dot impact device or the like. Alternatively, highly pressurized air can be blown with an air gun or the like, or the pressure can be applied with an ultrasonic generator, a piezoelectric element, or the like.

[0126] The pressure required for pressurization is 20 kg/cm2
or more, preferably 50 kg/cm2 or more. The photosensitive material of the present invention has many uses such as a photosensitive material for color photography and printing, a photosensitive material for printing, a photosensitive material for computer graphics hard copy, and a photosensitive material for copying machines. It is possible to create image forming systems such as copying machines, printers, and simple printing machines.

[0127]

[Example] Example 1 Preparation of silver halide emulsion (EB-1) A stirring gelatin aqueous solution (containing 20 g of gelatin and 3 g of sodium chloride in 1000 ml of water, kept at 75°C) was added with 21 g of sodium chloride and an odor solution. 600 ml of an aqueous solution containing 56 g of potassium chloride and a silver nitrate aqueous solution (600 ml of water)
0.59 mol of silver nitrate dissolved in
Added at equal flow rate over 0 min. In this way, a monodisperse cubic silver chlorobromide emulsion (80 mol % bromine) with an average grain size of 0.35 μm was prepared. After washing the emulsion with water to desalt it, 5 mg of sodium thiosulfate and 20 mg of 4-hydroxy-6-methyl-1,3,3a,7-tetrazaindene were added to perform chemical sensitization at 60°C. . The yield of emulsion was 600 g. Preparation of benzotriazole silver emulsion (EB-2) 28 g of gelatin and 13.2 g of benzotriazole were mixed in 3000 ml of water.
Dissolved in l. This solution was stirred while being maintained at 40° C., and a solution of 17 g of silver nitrate dissolved in 100 ml of water was added over 2 minutes. Excess salt precipitation was removed by adjusting the pH of the resulting emulsion. Thereafter, the pH was adjusted to 6.30 to obtain a benzotriazole silver emulsion. The yield of emulsion is 40
It was 0g.

Preparation of solid dispersion (KB-1) 300ml
110 g of a 5.4% aqueous solution of lime-processed gelatin, polyethylene glycol (average molecular weight 200
0), 20 g of a 5% aqueous solution of base precursor (BG-1
) and 200 ml of glass beads with a diameter of 0.5 to 0.75 mm were added, and the mixture was heated at 3000 rpm using a Dyno Mill.
p. m. Disperse for 20 minutes and adjust the pH to 6.5 with 2N sulfuric acid.
Base precursor (B) with a particle size of 1.0 μm or less
A solid dispersion (KB-1) of G-1) was obtained.

[0129]

[C27]

Preparation of photosensitive composition (PB-1) To 45 g of polymerizable compound (MN-2) was added copolymer (1P-1) (
SV-1) 9 g of 20% (wt%) solution, (RD-1)
2.3g, (RD-2) 6.2g, (FF-3) (S
V-1) 1 g of 0.5% (wt%) solution and (ST-
1) 5g was added and dissolved to prepare an oily solution. To this solution were added 3.8 g of silver halide emulsion (EB-1), 3.8 g of benzotriazole silver emulsion (EB-2), and 24 g of solid dispersion (KB-1), and while keeping the temperature at 60°C, The W/O emulsion photosensitive composition (
PB-1) was obtained.

[0131]

[C28]

[0132]

[C29]

[0133]

[C30]

Photosensitive microcapsule dispersion (CB-1
) Preparation Add 36 g of water to 4 g of a 15% aqueous solution of polymer (2P-1).
The pH of the mixed solution was adjusted to 5.0 with 2N sulfuric acid. 60 g of a 10% aqueous solution of polymer (2P-2) was added to this liquid and mixed at 60°C for 30 minutes. This mixed solution was added to the photosensitive composition (PB-1) and stirred for 20 minutes at 60°C and 2500 revolutions per minute using a 40φ dissolver.
An emulsion in the form of a /O/W emulsion was obtained.

Separately, 52.2 g of a 37% formaldehyde aqueous solution and 170.3 g of water were added to 31.5 g of melamine, heated to 60° C., and stirred for 30 minutes to obtain a transparent aqueous solution of melamine/formaldehyde initial condensate. . 25 g of this initial condensate was added to 148 g of the above W/O/W emulsion cooled to 25°C, and the mixture was heated at 1200 r with a propeller blade.
The pH was adjusted to 5.0 using 2N sulfuric acid while stirring at pm.

[0136] Next, the temperature of this liquid was raised to 70°C over 30 minutes, and the mixture was further stirred for 30 minutes. Add to this 40% of urea.
% aqueous solution was added, the pH was adjusted to 3.5 with 2N sulfuric acid, and stirring was continued at 70°C for an additional 40 minutes. After cooling this liquid to 25° C., the pH was adjusted to 6.5 using a 2N aqueous sodium hydroxide solution, and the melamine formaldehyde resin was used as the capsule wall. A photosensitive microcapsule dispersion (CB-1) was prepared.

Polymer (2P-1) Polyvinylbenzenesulfinate potassium polymer (2P-2) Polyvinylpyrrolidone K
-90

Preparation of photosensitive material 101 118 g of photosensitive microcapsules (CB-1), 0.5 g of surfactant (WW-1), 1.3 g of a 10% aqueous solution of surfactant (WW-2), PVA KL318 ( 25 g of a 10% aqueous solution of carboxy-modified PVA (manufactured by Kuraray) was added and mixed at 40°C.

[0139] This coating solution was applied onto the following support (RS-1) by an extrusion method in a coating amount of 131 cc/m.
2, after drying at 60℃, 25℃, 65%
It was rolled up under the following conditions so that the coated side was on the inside. This photosensitive material was sealed in a moisture-proof bag laminated with aluminum under conditions of 25° C. and 55%.

[0140]

[Chemical formula 31]

Preparation of support (RS-1) Calcium carbonate (PC700, manufactured by Shiroishi Kogyo Co., Ltd.) 240 g, 40% sodium hexametaphosphate aqueous solution 30 g, and 3.5 g
After stirring and mixing 100 g of zinc -di-α-methylbenzylsalicylate, 5.6 g of surfactant (Poise 520, manufactured by Kao Corporation), and 354.4 ml of water, the mixture was stirred and mixed using a dispersion machine (product name: Ultra Disperser (LK)). -41 model) manufactured by Yamato Chemical Co., Ltd.) for 3 minutes at 8000 revolutions per minute. 52g of this dispersion and 10% polyvinyl alcohol (
52 g of an aqueous solution of PVA-117 (manufactured by Kuraray Co., Ltd.) were mixed, and 4 ml of a 1% aqueous solution of the following surfactant and 22 ml of water were added to prepare a coating solution for forming an image-receiving layer containing a color developer.

[0142]

[C32]

[0143] This coating solution was applied to a paper support with a basis weight of 80 g/m2 (as the fiber length distribution specified by JIS-P-8207, the sum of the weight % of the 24 mesh residue and the weight % of the 42 mesh residue was 30 Paper support using base paper having a fiber length distribution of 60% to 60% [JP-A-63-18623
9]), the image receiving layer was coated on the support (
RS-1) was created. On this support, 0.8 g of a diarylphthalide leuco dye (5) shown in the structural formula above was dissolved in 500 cc of toluene.
/m2, and then dried at 40°C to form a blue bleachable dye layer.

Image Formation The following experiments were carried out at 25° C. and 50%. The color temperature of the photosensitive material 101 taken out from the moisture-proof bag was 3100°K.
Using a halogen lamp adjusted to
Wedge with transmission density of ~4.0 and density 1.0
The image was exposed to light at 20,000 lux and for 1 second through a yellow and magenta CC filter (manufactured by Fuji Film) to match the gray balance and an ND filter. After 30 seconds of exposure, heat development was carried out for 2 seconds from the side opposite to the coated side of the photosensitive material using a heat developing machine equipped with an exhaust device heated to 150°C.

Two seconds after heating, the photosensitive material was pressed at a pressure of 900 kg/cm2 using a pressure roller, and a clear negative image was obtained. Set the density of this image to “X”
- When measured with Rite 310'', the maximum concentration was 1.3
5. Good contrast with a minimum density of 0.08 was obtained.

Example 2 Using the same photosensitive material as in Example 1, after 2 seconds of heating, the photosensitive material was passed through a pressure roller heated to 70° C. and heated and pressed at a pressure of 300 kg/cm2. However,
After all, a clear negative image was obtained. Set the density of this image to “
When measured with X-Rite 310'', the highest concentration was 1.
43. Good contrast was obtained with a minimum density of 0.12.

Claims (1)

[Claims] 1. A photosensitive material containing a bleachable dye and photosensitive microcapsules encapsulating at least silver halide, a reducing agent, and a polymerizable compound on a support is imagewise exposed, and then developed. An image forming method that obtains an image by applying pressure.