JP2006201266A - Diffusion/transfer film unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a color diffusion/transfer film unit in which the progression of transfer is quick, and the whiteness of a white background part is high. <P>SOLUTION: The diffusion/transfer film unit includes: a photosensitive sheet which has, on the surface of a transparent support, an image receiving layer, a white light diffusion layer containing titanium dioxide particulates dispersed in gelatin, a light shielding layer, and one or more silver halide emulsion layers combined with at least one pigment image forming substance; a transparent cover sheet which has, on the surface of a support, a neutralization layer and a neutralization timing layer; and an alkali treatment composition containing a light shielding agent developed after exposure between the photosensitive sheet and the transparent cover sheet, and they are arranged so as to be exposed through the transparent cover sheet, and in the white light diffusion layer positioned between the image receiving layer and the light shielding layer. The mass ratio of the titanium dioxide/gelatin is ≤10, the content of the gelatin is ≤1.7 g/m<SP>2</SP>, and the mass ratio between the titanium dioxide particulates and spacer particulates is 10:1 to 10:5. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a diffusion transfer film unit. More specifically, the present invention relates to an integrated color diffusion transfer film unit. The present invention also relates to a color diffusion transfer film unit having a thin film unit, a rapid transfer progress, and a low density in an unexposed area.

  The color diffusion transfer film unit includes an integral type and a divided type. One typical example of the split type is a so-called peel-apart type, in which the photosensitive element and the dye-receiving element are coated on different supports, and after image exposure, the photosensitive element and the dye-receiving element are separated. The dye image transferred to the dye image-receiving layer is obtained by superimposing and developing the treatment composition between them, and then peeling off the dye-receiving element. The feature of this embodiment is that the dye image can be directly observed instead of observing the image through the support as in the case of the integrated type described later, and shows excellent color reproducibility without deterioration in image quality. However, in this embodiment, there is an inconvenience in operation in which the photosensitive element and the image receiving element are superposed in the camera, and an inconvenience in handling the processed film in which the alkaline processing liquid is sticky and easily adheres to the periphery after peeling. is there.

  In this operation, the one that improves inconvenience in handling is an integrated form. The integrated diffusion transfer film unit is described in many documents such as Non-Patent Documents 1 and 2, and is well known. In the integrated type, a dye image-receiving element, a photosensitive element, and a neutralization timing element are coated between a transparent support and the other support, and the photosensitive element is coated on the same transparent support as the image-receiving element. And a form coated on another support (hereinafter referred to as the latter).

  In the former case, a white light diffusion layer is coated between the image receiving element and the photosensitive element. In the latter case, the image is received by adding a white pigment to the processing composition developed between the image receiving element and the photosensitive element. The dye image transferred to the layer can be observed with reflected light.

  For the color diffusion transfer film unit, a light-shielding layer and a light-shielding alkali treatment composition are usually used. The role of the light-shielding layer and the light-shielding alkali treatment composition is an element necessary for darkening the silver halide emulsion layer after the treatment. Film units released from the film pack after processing will be completely exposed to light. In the absence of a light-shielding layer, light reaches the silver halide emulsion layer after processing, so that the unexposed areas are exposed and developed, and are colored during storage. For this reason, it is necessary to make a dark room with a light shielding layer. However, when the silver halide emulsion layer is darkened from the beginning, imagewise exposure cannot be performed. For this reason, the exposure side is designed to allow light to pass through during exposure and to develop a dark room by developing a light-shielding alkaline composition and covering the other surface during processing. A light shielding layer is necessary for darkening, but the light shielding layer must be black in order to shield light in the entire wavelength range. However, if the film unit is black, an image transferred like an image cannot be transferred. In order to solve this problem, the above-described white light diffusion layer is necessary. The white light diffusion layer is placed between the image receiving layer and the light shielding layer and covers the black color of the shielding layer to form a white background. The presence of the white light diffusion layer makes it possible to obtain an image in which the unexposed portion is white.

A fine powder of titanium oxide is used in the white light diffusion layer of the current color diffusion transfer film unit. Various types of binders have been studied, but gelatin is generally used. In the diffusion transfer film unit of the present invention, a large amount of fine titanium oxide particles are required to form a beautiful white background where the unexposed portion can be appreciated, and a large amount is required to disperse it so that it can be applied uniformly. However, the large amount of gelatin applied causes a delay in transfer progress. For example, Patent Document 1 proposes the use of a light-reflective organic polymer for the white light diffusion layer, but there is no description of the transfer progress delay. Under such circumstances, it has been desired to develop a technique for accelerating the transfer while maintaining the whiteness of the white background.
JP 61-151646 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide a color diffusion transfer unit in which transfer progress is fast and whiteness of a white background portion is high.

The above problems have been achieved by the following means.
(1) a photosensitive sheet having an image receiving layer on a transparent support, a white light diffusing layer containing titanium dioxide fine particles dispersed in gelatin, a light shielding layer, and a silver halide emulsion layer combined with a dye image-forming substance; A transparent cover sheet having a neutralization layer on the support, and a neutralization timing layer, and an alkali treatment composition containing a light-shielding agent developed after exposure between the photosensitive sheet and the transparent cover sheet, These are diffusion transfer film units arranged so as to be exposed through a transparent cover sheet, and the titanium dioxide / gelatin mass ratio in the white light diffusion layer provided between the image receiving layer and the light shielding layer in the photosensitive sheet is 10 or less, and the gelatin content of the white light diffusion layer is 1.7 g / m ² or less, and the white light diffusion layer further contains spacer fine particles, A diffusion transfer film unit, wherein the titanium dioxide fine particles and the spacer fine particles in the white light diffusion layer are expressed as titanium dioxide: spacer fine particles in a mass ratio of 10: 1 to 10: 5.
(2) The diffusion transfer film unit according to (1), wherein the spacer fine particles are organic polymer fine particles.
(3) The diffusion transfer film unit according to (1), wherein the spacer fine particles are silica fine particles.
(4) The diffusion transfer film unit according to any one of (1) to (3), wherein the exposure is performed using an exposure head having different light sources that emit light in a plurality of specific wavelength regions.

  In the diffusion transfer film unit of the present invention, the transfer progresses quickly and the whiteness of the white portion can be increased.

  The diffusion transfer film unit of the present invention comprises an image receiving layer on a transparent support, a white light diffusion layer containing titanium dioxide fine particles dispersed in gelatin, a light shielding layer, and a silver halide emulsion combined with a dye image forming material. A photosensitive sheet having a layer, a transparent cover sheet having a neutralization layer and a neutralization timing layer on a support, and an alkali treatment composition containing a light-shielding agent developed after exposure between the photosensitive sheet and the transparent cover sheet And these are diffusion transfer film units arranged to be exposed through the transparent cover sheet. A white light diffusion layer is provided between the image receiving layer and the light shielding layer in the photosensitive sheet. First, the white light diffusion layer in the present invention will be described. The white light diffusion layer contains titanium dioxide fine particles dispersed in gelatin. Titanium dioxide fine particles are originally a transparent material, but diffuse light at the interface with air or a binder to form a white background. The refractive index of air or binder is about 1 to 1.5, whereas the refractive index of titanium oxide is 2.6 or more. Due to this large refractive index difference, the incident light is greatly bent to increase the reflection component and form an excellent white background.

Titanium dioxide used in the present invention may be either a rutile type or anatase type crystal system, but a rutile type is preferred. The average size (particle size) of the titanium dioxide particles is not particularly limited as long as it is a size having a visible scattering component, but it is preferably 0.2 to 0.4 μm. Most of the commercially available products are surface-treated with alumina, silica, zinc oxide or the like, and a surface treatment amount of 5% or more is preferable to obtain high reflectance. Examples of commercially available titanium dioxide include Du-Pont Ti-pure R931, Ishihara Sangyo Typek R-780 (both trade names) and those described in Research Disclosure No. 15162. The coating amount of titanium dioxide is preferably 3 to 20 g / m ² , more preferably 7 to 15 g / m ² .

The binder of the white light diffusing layer must allow the dye to pass through and diffuse, and in the present invention, at least one kind of gelatin is used. Gelatin includes gelatin derivatives and graft polymers of gelatin and other polymers. Further, in the present invention, in addition to gelatin as a binder for the white light diffusing layer, an alkali-permeable polymer matrix other than gelatin, for example, proteins such as albumin and casein, cellulose derivatives such as hydroxyethyl cellulose, carboxymethyl cellulose, and cellulose sulfates Synthetic hydrophilic, such as sugar derivatives such as sodium alginate, starch, polyvinyl alcohol, polyvinyl alcohol partial acetal, poly-N-vinyl pyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide etc. A polymer material can be used. The content of gelatin in the white light diffusing layer needs to be sufficient for titanium dioxide to stably exist without agglomerating in the film. In the present invention, the titanium dioxide / gelatin mass ratio is 10 or less, preferably 3 to 10, more preferably 7 to 10. If the amount of titanium dioxide is too much relative to gelatin, the titanium dioxide particles aggregate and cause image defects. If the amount of titanium dioxide is too small relative to gelatin, sufficient whiteness cannot be obtained.
In the present invention, the gelatin coating amount of the white light diffusion layer is 1.7 g / m ² or less, preferably 1.7 g / m ^{2 to} 0.5 g / m ² , more preferably 1.4 g / m ^{2 to} 0.6 g / m. a m ^2. If the amount of gelatin applied is too large, transfer progress is delayed and image formation is delayed.

The white light diffusion layer of the present invention contains titanium dioxide and spacer fine particles in a mass ratio of 10: 1 to 10: 5, preferably 10: 2 to 10: 4, when expressed as titanium dioxide: spacer fine particles. If there is too much titanium dioxide relative to the spacer fine particles, image formation will be slow, and if it is too little, sufficient whiteness cannot be obtained.
As the spacer fine particles, fine particles (excluding titanium dioxide) made of a material that does not substantially absorb in the visible region can be used. As the inorganic material, for example, a silica fine particle dispersion can be used, and as the organic material, for example, an organic polymer fine particle dispersion made of styrene or the like can be applied and used.

Many silica fine particle dispersions are known, for example, “Manufacturing and Application of High-Purity Silica” published by CMC, JP-B-1-23411, JP-A-1-145317, 5 Specific examples are described in JP-A-85716.
For example, various sizes of amorphous silica fine particle dispersions can be purchased from Nippon Shokubai Co., Ltd.
The silica fine particle dispersion used in the present invention preferably has an average diameter of 0.1 μm to 1.5 μm, and most preferably 0.2 μm to 0.5 μm. Moreover, what can be applied with an aqueous solvent has a great merit in terms of production.

With regard to the composition and production method of the organic polymer fine particles, many specific examples are described in “Application Technology of Ultra Fine Particle Polymer” published by CMC. There is no restriction | limiting in particular about the composition of an organic polymer to be used, and a manufacturing method, If it is transparent or white, it can be used. Examples of the organic polymer fine particles are described in many documents and are not particularly limited. For example, JP-A-56-32513, 61-243803, 63-189413, 60-258203, JP-A 64-1702, JP-B-57-24369, JP-B-6-102688, JP-B-3275397, JP-A-5-125127, JP-A-3-26724, JP-A-2-240108, and US Pat. No. 3,740,367. Those described in the specification can be used.
The organic polymer fine particles used in the present invention preferably have an average particle size (diameter) of 0.1 to 0.8 μm, more preferably 0.2 μm to 0.5 μm. Moreover, it is preferable that Tg value (glass transition temperature) is 200 degreeC or more.

  Among the organic polymer fine particles used in the present invention, particularly preferred is a light-reflective hollow polymer latex containing air inside and a material made of organic polymer. For example, U.S. Pat. Nos. 2,339,707, 2,739,909, 2,961,339, 3,157,533, 3,328,184, 3,372,044, Nos. 3,478,716, 3,766,102, and 3,896,138, and British Patent Nos. 062,702 and 962,223.

Specific examples of the polymer latex forming the fine particle polymer and the hollow polymer are addition polymerization ethylenic homopolymer and copolymer latex. Specific examples of the addition polymerizable ethylenically unsaturated compound are shown below.
Acrylic acid;
Methacrylic acid;
Acrylic esters (substituted or unsubstituted alkyl or aryl esters such as methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, octyl acrylate, 2-chloroethyl acrylate, 2-cyanoethyl acrylate, N- (β-dimethylamino Ethyl) acrylate, benzyl acrylate, cyclohexyl acrylate, phenyl acrylate);
Methacrylic acid esters (substituted or unsubstituted alkyl or aryl esters such as methyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, cyclohexyl methacrylate, 3-sulfopropyl methacrylate);
Allyl compounds (allyl butyl ether, allyl phenyl ether);
Vinyl ethers (for example, methyl vinyl ether, butyl vinyl ether, methoxyethyl vinyl ether, 2-hydroxymethyl vinyl ether, (2-dimethylaminoethyl) vinyl ether, vinyl phenyl ether, vinyl chlorophenyl ether);
Acrylamides (eg acrylamide, n-methylacrylamide, n- (1,1-dimethyl-3-oxobutyl) acrylamide, n- (1,1-dimethyl-3-hydroxybutyl) acrylamide, N, N-dimethylacrylamide, acryloyl Hydrazine, n-hydroxymethylacrylamide);
Methacrylamides (eg, methacrylamide, N-methoxymethylmethacrylamide, N- (1,1-dimethyl-3-hydroxybutyl) methacrylamide);
Vinyl heterocycles (eg vinylpyridine, N-vinylimidazole, N-vinylcarbazole, vinylthiophene);
A styrene ring (eg, styrene, chloromethylstyrene, P-acetoxystyrene, P-methylstyrene);
Vinyl esters (eg, p-vinylbenzoic acid, methyl P-vinylbenzoate);
Vinyl ketones (eg methyl vinyl ketone, phenyl vinyl ketone);
Crotonic acid esters (eg butyl crotonic acid, glycerin monocrotonate);
Itaconic acid esters (eg, methyl itaconate, ethyl itaconate, diethyl itaconate);
Maleate esters (eg, ethyl maleate, butyl maleate, dibutyl maleate, octyl maleate);
Fumarate esters (eg, ethyl fumarate, dibutyl fumarate, octyl fumarate)
Unsaturated nitriles (eg acrylonitrile, methacrylonitrile);
Olefins (including halogenated ones such as ethylene, propylene, 1-butene, dicyclopentadiene, 4-methyl-1-hexene, 4,4-dimethyl-pentene vinyl chloride, encabinylidene, isoprene);

  There is no particular limitation on the ratio (molar ratio) of the comonomers used in the case of the copolymer latex, and it can be appropriately selected. A hollow polymer latex obtained from a copolymer of styrene and acrylic acid can be purchased as SX866 marketed by JSR. Further, the polymer latex preferably has no film property. For such a polymer latex, gelatin or a derivative thereof, or a binder known for photography such as polyvinyl alcohol, hydroxyethyl cellulose, carboxymethyl cellulose, polyvinyl pyrrolidone and an arbitrary ratio. Can be mixed and used. A polymer latex that can be applied with a water solvent has a great merit in terms of production.

As gelatin, besides lime-processed gelatin, acid-processed gelatin may be used, and gelatin hydrolyzate and gelatin enzyme dispersion may also be used. Examples of gelatin derivatives include various compounds such as acid halides, acid anhydrides, isocyanates, bromoacetic acid, alkane sultones, vinyl sulfonamides, maleimide compounds, polyalkylene oxides, epoxy compounds and the like. What is obtained by reacting is used.
Further, it is preferable to incorporate an anti-fading agent such as Japanese Patent Publication Nos. Sho 62-30620 and 62-30621 in the white light diffusion layer.

  In the formation of the white light diffusion layer used in the present invention, it is preferable to disperse the titanium dioxide fine particles using a surfactant. Any surfactant can be used as the surfactant, but nonionic surfactants are preferred.

  Next, the nonionic surfactant used in the present invention will be described. Nonionic surfactants are represented by the following general formulas (W-II), (W-III), (W-IV), (W-V), (W-VI) and (W-VII). Can be used.

In the general formulas (W-II) to (W-VII), R, R ¹ , R ² and R ³ represent a hydrogen atom, an alkyl group or an alkenyl group having 8 or more carbon atoms, and R, R ¹ , R ² and R ³ may be the same or different, except for those that are all hydrogen atoms. R ⁴ represents an alkyl group or alkenyl group having 8 or more carbon atoms, and n represents a positive integer of 5 to 100. R ₂₁ represents a hydrogen atom or an alkyl group having 1 to 30 carbon atoms, an alkenyl group or an aryl group, and these groups include those having a substituent. R ₂₁ is preferably an alkyl group having 4 to 24 carbon atoms, an alkenyl group, or an aryl group, and particularly preferably a hexyl group, dodecyl group, isostearyl group, oleyl group, t-butylphenyl group, 2,4-di- t-butylphenyl group, 2,4-di-t-pentylphenyl group, p-dodecylphenyl group, n-pentadecaphenyl group, t-octylphenyl group, 2,4-dinonylphenyl group, octylnaphthyl group, etc. It is. A is —O—, —S—, —COO—, —OCO—, —N (R ₃₀ ) —, —CON (R ₃₀ ) — or —SO ₂ N (R ₃₀ ) — (where R ₃₀ is hydrogen). Represents an alkyl group including those having an atom or a substituent. R ₂₂ , R ₂₃ , R ₂₇ and R ₂₉ represent a hydrogen atom, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, a halogen atom, an acyl group, an amide group, a sulfonamide group, a carbamoyl group or a sulfamoyl group, These groups include those each having a substituent. R ₂₆ and R _{28 each} represents an alkyl group, an aryl group, an alkoxy group, an aryloxy group, a halogen atom, an acyl group, an amide group, a sulfonamide group, a carbamoyl group or a sulfamoyl group, and these groups each have a substituent. Is also included. R ₂₆ and R ₂₈ are preferably an aryl group such as an alkyl group having 1 to 20 carbon atoms, a phenyl group, or a p-chlorophenyl group, and —OR ₃₅ (wherein R ₃₅ represents an alkyl group or aryl group having 1 to 20 carbon atoms). These groups include those having a substituent. The same shall apply hereinafter.) Alkyl groups and aryloxy groups, halogen atoms such as chlorine atoms and bromine atoms, and acyl groups represented by —COR ₃₅ An amide group represented by the group, —NR ₃₆ COR ₃₅ (wherein R ₃₆ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms; the same shall apply hereinafter), represented by —NR ₃₆ SO ₂ R _35. A sulfonamide group, a carbamoyl group represented by —CON (R ₃₆ ) ₂ or a sulfamoyl group represented by —SO ₂ N (R ₃₆ ) ₂ . Of these, R ₂₆ and R ₂₈ are more preferably an alkyl group or a halogen atom, and most preferably a tertiary alkyl group such as a t-butyl group, a t-amyl group, or a t-octyl group. R ₂₂ , R ₂₃ , R ₂₇ and R ₂₉ are preferably hydrogen atoms or the groups listed as preferred for R ₂₆ and R ₂₈ above. Of these, R ₂₇ and R ₂₉ are particularly preferably hydrogen atoms. R ₂₄ and R ₂₅ represent a hydrogen atom, an alkyl group or an aryl group, and these groups include those having a substituent. R ₂₄ and R ₂₅ are particularly preferably a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a phenyl group, a furyl group, or the like. R ₂₄ and R ₂₅ , R ₂₆ and R _27, and R ₂₈ and R ₂₉ may be linked to each other to form a ring, for example, a cyclohexyl ring. In the general formula (W-VI), the substituent on the phenyl ring may be asymmetrical. R ₃₁ represents a hydrogen atom or an alkyl group, and this alkyl group includes those having a substituent. R ₃₂ represents a hydrogen atom or an alkyl group having 1 to 30 carbon atoms, an alkenyl group, an aryl group or an aralkyl group. Each group represented by R ₃₂ includes those having a substituent. Examples of the substituent include an alkyl group, an aryl group, a halogen atom, an alkoxy group, an aryloxy group, a thioether group, and a polyoxyalkyl ether group. It is done. R ₃₃ represents an alkylene group having 1 to 10 carbon atoms, a polyoxyalkylene group or a divalent aromatic group (for example, a phenylene group), and these include those having a substituent. R ₃₄ represents an alkyl group having 1 to 20 carbon atoms or an aryl group. Each group represented by R ₃₄ includes those having a substituent. Examples of the substituent include an alkyl group, an aryl group, a halogen atom, an alkoxy group, an aryloxy group, a thioether group, and a polyoxyalkylene ether group. Can be mentioned. n ₁₁ , n ₁₂ , n ₁₃ and n ₁₄ are the average number of moles of ethylene oxide added, and are 2 to 50, particularly preferably 5 to 30. n ₁₃ and n ₁₄ may be the same or different. The n ₁₅ is the same number of an average addition mole number of ethylene oxide 1-100. m is an integer of 2 to 50, m ₁₁ and m ₁₂ are each an integer of 0 to 20, and p is an integer of 0 to 30. These compounds are disclosed in U.S. Pat. Nos. 2,982,651, 3,428,456, 3,457,076, 3,454,625, 3,552,972, 3, No. 655,387, Japanese Patent Publication No. 51-9610, Japanese Patent Publication No. 53-29715, Japanese Patent Publication No. 54-89626, Japanese Patent Application No. 57-85764, Japanese Patent Application No. 57-90909, Hiroshi Horiguchi, “New Interface Activator "(Sankyo Publishing, 1975) and the like. Among the nonionic surfactants represented by the general formulas (W-II) to (W-VII), those preferably used are sorbitan ester compounds represented by (W-II) and (W-III). . Next, specific examples of the nonionic surfactant preferably used in the present invention will be shown, but the present invention is not limited thereto.

The addition amount of these surfactants is not particularly limited, but is preferably 1 × 10 ⁻⁵ g / m ² to 1 g / m ² , and preferably 1 × 10 ⁻⁴ g / m ² to 1 × 10 ^−1. g / m ² is more preferable, and 1 × 10 ⁻³ g / m ² to 1 × 10 ⁻² g / m ² is particularly preferable.

  Examples of each component that can be used in the diffusion transfer film unit of the present invention will be described below.

I. Photosensitive sheet The photosensitive sheet used in the present invention comprises an image receiving layer, a white light diffusing layer, a light shielding layer, and at least one silver halide emulsion layer combined with at least one dye image-forming substance on a transparent support. A photosensitive sheet. The configuration other than the white light diffusion layer will be described below.

B) Light-shielding layer A light-shielding layer containing a light-shielding agent and a hydrophilic binder is provided between the white light diffusion layer and the following photosensitive layer. As the light shielding agent, any material having a light shielding function is used, but carbon black is preferably used. Further, degradable dyes described in US Pat. No. 4,615,966 may be used. The binder for coating the light-shielding agent may be any one that can disperse the light-shielding agent, and is preferably gelatin. As the carbon black raw material, any method such as a channel method, a thermal method and a furnace method as described in Donnel Voet “Carbon Black” Marcel Dekker, Inc. (1976) can be used. The particle size of carbon black is not particularly limited, but is preferably 90 to 1800 mm. The addition amount of the light-shielding agent may be adjusted according to the sensitivity of the light-sensitive material to be shielded from light, but is preferably about 5 to 10 in terms of optical density.
The thickness of the light shielding layer used in the present invention is not particularly limited.

C) Support The support of the photosensitive sheet used in the present invention is any smooth transparent support that is usually used for photographic light-sensitive materials, and cellulose acetate, polystyrene, polyethylene terephthalate, polycarbonate, etc. are used, and an undercoat layer is used. (Undercoat layer) is preferably provided. In general, the support preferably contains a trace amount of a dye or a pigment such as titanium oxide in order to prevent light piping. The thickness of the support of the photosensitive sheet is 25 to 350 μm, preferably 50 to 210 μm, more preferably 70 to 150 μm. If necessary, a layer for curling balance or an oxygen barrier layer described in JP-A-56-78833 can be provided on the back side of the support.

D) Image receiving layer The image receiving layer (dye image receiving layer) of the photosensitive sheet used in the present invention includes a mordant contained in a hydrophilic colloid. This may be a single layer or a multilayer structure in which mordants having different mordant powers are applied in layers. These are described in JP-A-61-252551. As the mordant, a polymer mordant is preferable.
The polymer mordant is a polymer containing secondary and tertiary amino groups, a polymer having a nitrogen-containing heterocyclic moiety, a polymer containing a quaternary cation, etc., having a molecular weight of 5,000 or more, particularly preferably 10,000 or more. Is. The coating amount of the mordant is generally 0.5 to 10 g / m ^2, preferably 1.0 to 5.0 g / m ^2, particularly preferably ² to 4 g / m ² .

As the hydrophilic colloid used for the image receiving layer of the photosensitive sheet, gelatin, polyvinyl alcohol, polyacrylamide, polyvinyl pyrrolidone and the like are used, and gelatin is preferred.
In the image receiving layer, anti-fading agents described in JP-A Nos. 62-30620, 62-30621, and 62-215272 can be incorporated.
The thickness of the image receiving layer used in the present invention is not particularly limited.

E) Photosensitive layer In the present invention, a photosensitive layer comprising at least one silver halide emulsion layer combined with a dye image forming substance (dye image forming compound) is provided adjacent to the light shielding layer. The components will be described below.

(1) Dye Image Forming Compound Specific examples of the dye image forming compound that can be used in the present invention are described in the following documents.
Examples of yellow dyes:
U.S. Pat. Nos. 3,597,200, 3,309,199, 4,013,633, 4,245,028, 4,156,609, 4,139 No. 4,383, No. 4,195,992, No. 4,148,641, No. 4,148,643, No. 4,336,322, JP-A No. 51-114930, No. 56-71072, Research Disclosure 17630 (1978), and 16475 (1977).

Examples of magenta dyes:
U.S. Pat. Nos. 3,453,107, 3,544,545, 3,932,380, 3,931,144, 3,932,308, 3,954 No. 4,476, No. 4,233,237, No. 4,255,509, No. 4,250,246, No. 4,142,891, No. 4,207,104, 4,287,292, JP-A-52-106727, 53-23628, 55-36804, 56-73057, 56-71060, 55-134 , JP-A-7-120901, 8-286343, 8-286344, and 8-292537.

Examples of cyan dyes:
U.S. Pat. Nos. 3,482,972, 3,929,760, 4,013,635, 4,268,625, 4,171,220, 4,242 , 435, 4,142,891, 4,195,994, 4,147,544, 4,148,642; British Patent 1,551,138 Japanese Patent Laid-Open Nos. 54-99431, 52-8827, 53-47823, 53-143323, 54-99431, 56-71061; European Patent (EP) 53,037, 53,040; Research Disclosure 17,630 (1978) and 16,475 (1977).

A dye image forming compound that forms a dye by coupling can also be used. For example, they are described in JP-A-8-286340, JP-A-9-152705, JP-A-8-357190, JP-A-8-357191, JP-A-9-117529, and the like.
A positive type dye image forming compound can also be used. In this case, a negative silver halide emulsion may be used as the silver halide emulsion. Examples thereof include JP-A-4-156542, JP-A-4-155332, JP-A-4-172344, JP-A-4-172450, JP-A-4-318844, JP-A-356046, and JP-A-5-45824. Gazette, 5-45825 gazette, 5-53279 gazette, 5-107710 gazette, 5-241302 gazette, 5-107708 gazette, 5-232659 gazette, and U.S. Pat. No. 192,649.

  These compounds can be dispersed by the method described in JP-A-62-215272, pages 144-146. These dispersions may contain the compounds described in JP-A-62-215272, pages 137 to 144. Specific examples of these dye image forming compounds include the following compounds. Dye in the following compounds represents a dye group, a dye group temporarily shortened in wavelength, or a dye precursor group.

(2) Silver halide emulsion The silver halide emulsion used in the present invention may be, for example, silver chloride, silver bromide, silver iodobromide, silver chlorobromide, silver chloroiodide or silver chloroiodobromide. In particular, a negative type silver halide emulsion that forms a latent image on the surface of silver halide grains, or an internal latent image type direct positive emulsion that forms a latent image inside silver halide grains is preferred.

  The negative type emulsion that forms a latent image on the surface of the silver halide grain may be a so-called core-shell emulsion having a phase different from that of the inside of the grain and the surface of the grain, and silver halides having different compositions are joined by epitaxial joining. May be. The silver halide emulsion may be monodispersed or polydispersed, and a method of adjusting the gradation by mixing monodispersed emulsions as described in JP-A-1-167743 and 4-223463 is also used.

  The crystal habit of silver halide grains has regular crystals such as cubes, octahedrons, tetradecahedrons, spherical crystals, irregular crystal systems such as high aspect ratio flat plates, twins Any of those having a crystal defect such as a plane, a composite system thereof, or the like may be used.

  Specifically, US Pat. No. 4,500,626, column 50, US Pat. No. 4,628,021, No. 4, Research Disclosure (hereinafter abbreviated as RD) No. 17, 029 (1978), ibid. 17, 643 (December 1978) 22-23, the same No. 18, 716 (November 1979) 648, ibid. 307, 105 (November 1989) 863-865, JP-A-62-253159, JP-A-64-13546, JP-A-2-236546, JP-A-3-110555, and Grafkide, “Physics of Photography” And Chemistry ", published by Paul Monte (P. Glafkides, Chemie et Pisique Photographique, Paul Montel, 1967)," Photoemulsion Chemistry "by Duffin, published by Focal Press (GF Duffin, Photographic Emulsion Chemistry, Focal Press, 1966), “Production and Coating of Photographic Emulsions” by Zerikman et al., Published by Focal Press (V. L. Zelikman et al., Making and Coating Photographic Emulsion, Focal Press, 1964), etc. Any of the prepared silver halide emulsions can be used.

  In the process of preparing a photosensitive silver halide emulsion, it is preferable to perform so-called desalting to remove excess salt. As a means for this, a Nudell water washing method in which gelatin is gelled may be used, and inorganic salts (for example, sodium sulfate) composed of polyvalent anions, anionic surfactants, anionic polymers (for example, polystyrene sulfonic acid) Sodium), or a precipitation method using a gelatin derivative (for example, aliphatic acylated gelatin, aromatic acylated gelatin, aromatic carbamoylated gelatin, etc.) may be used. A sedimentation method is preferably used.

The photosensitive silver halide emulsion used in the present invention may contain, for example, heavy metals such as iridium, rhodium, platinum, cadmium, zinc, thallium, lead, iron and osmium for various purposes. These compounds may be used alone or in combination of two or more. The amount added depends on the purpose of use, but is generally about 10 ⁻⁹ to 10 ⁻³ mol per mol of silver halide. Moreover, when making it contain, you may put in a particle | grain uniformly and you may make it local in the inside and surface of particle | grains. Specifically, emulsions described in JP-A-2-236542, 1-116637, and 5-181246 are preferably used.

  In the grain forming stage of the photosensitive silver halide emulsion, rhodan salts, ammonia, tetrasubstituted thioether compounds, organic thioether derivatives described in JP-B-47-11386 or JP-A-53-144319 are described as silver halide solvents. Sulfur-containing compounds that have been used can be used.

  Other conditions are described in the above-mentioned Graffkide, "Photo Physics and Chemistry" published by Paul Monte (P. Glafkides, Chemie et Pisique Photographique, Paul Montel, 1967), Duffin's "Photo Emulsion Chemistry", Focal Press ( GF Duffin, Photographic Emulsion Chemistry, Focal Press, 1966), “Production and Coating of Photographic Emulsions” by Zerikman et al., Published by Focal Press (V. L. Zelikman et al., Making and Coating Photographic Emulsion, Focal Press , 1964). That is, any of an acidic method, a neutral method, and an ammonia method may be used, and any one of a one-side mixing method, a simultaneous mixing method, and a combination thereof may be used as a form for reacting a soluble silver salt and a soluble halogen salt. In order to obtain a monodisperse emulsion, a simultaneous mixing method is preferably used. A backmixing method in which grains are formed in the presence of excess silver ions can also be used. As one type of the simultaneous mixing method, a so-called controlled double jet method in which pAg in a liquid phase in which silver halide is generated is kept constant can be used.

  In order to accelerate grain growth, the addition concentration, addition amount, and addition rate of silver salt and halogen salt to be added may be increased (Japanese Patent Laid-Open Nos. 55-142329 and 55-158124, US Patent). 3650757, etc.). Furthermore, the stirring method of the reaction solution may be any conventional stirring method. Further, the temperature and pH of the reaction solution during the formation of silver halide grains may be set in any manner according to the purpose. A preferred pH range is 2.3 to 8.5, more preferably 2.5 to 7.5.

The photosensitive silver halide emulsion is usually a chemically sensitized silver halide emulsion.
For chemical sensitization of light-sensitive silver halide emulsions, known emulsions for light-sensitive materials include known sulfur sensitizing methods, selenium sensitizing methods, chalcogen sensitizing methods such as tellurium sensitizing methods, gold, platinum, palladium, etc. The noble metal sensitizing method and the reduction sensitizing method to be used can be used alone or in combination (for example, JP-A-3-110555 and JP-A-5-241267). These chemical sensitizations can also be performed in the presence of a nitrogen-containing heterocyclic compound (Japanese Patent Laid-Open No. 62-253159). An antifoggant can be added after the chemical sensitization. Specifically, the methods described in JP-A-5-45833 and JP-A-62-240446 can be used. The antifoggant used in the present invention is preferably added at the end of chemical sensitization.

The pH during chemical sensitization is preferably 5.3 to 10.5, more preferably 5.5 to 8.5, and the pAg is preferably 6.0 to 10.5, more preferably 6.8 to 9 .0. The coating amount of the photosensitive silver halide used in the present invention is in the range of 1 mg / m ^{2 to} 10 g / m ^{2 in} terms of silver, and preferably 10 mg / m ^{2 to} 10 g / m ² .

  In order to give the photosensitive silver halide used in the present invention green sensitivity, red sensitivity, and blue sensitivity, the photosensitive silver halide emulsion is spectrally sensitized with methine dyes and the like. Moreover, you may give infrared-sensitive spectral sensitization as needed.

  The dyes used include cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes, styryl dyes and hemioxonol dyes. Specific examples include sensitizing dyes described in U.S. Pat. No. 4,617,257, JP-A-59-180,550, JP-A-64-13546, JP-A-5-45828, and JP-A-5-45834. Is mentioned. These sensitizing dyes may be used alone, or a combination thereof may be used, and the combination of sensitizing dyes is often used for the purpose of adjusting the wavelength of supersensitization or spectral sensitization.

In addition to the sensitizing dye, a dye that does not itself have spectral sensitizing action or a compound that does not substantially absorb visible light and exhibits supersensitization may be contained in the emulsion (for example, US Pat. 615,641, JP-A-63-23145, etc.). These sensitizing dyes may be added to the emulsion before or after chemical ripening, or before or after nucleation of silver halide grains according to US Pat. Nos. 4,183,756 and 4,225,666. Good. These sensitizing dyes and supersensitizers may be added in a solution of an organic solvent such as methanol, a dispersion such as gelatin, or a surfactant solution. The amount added is generally about 10 ⁻⁸ to 10 ⁻² mole per mole of silver halide.

  Internal latent image type direct positive emulsions include, for example, so-called “conversion type” emulsions made by utilizing the difference in solubility of silver halide, metal ions doped, chemically sensitized, or both. There is a “core / shell type” emulsion in which at least the photosensitive sites of the inner core (core) grains of the silver halide applied are coated with an outer shell (shell) of silver halide. 592,250, 3,206,313, British Patent 1,027,146, US Patents 3,761,276, 3,935,014, 3,447,927, 2, 297,875, 2,563,785, 3,551,662, 4,395,478, West German Patent 2,728,108, US Pat. No. 4,431,730, etc. ing

  When an internal latent image type direct positive emulsion is used, it is necessary to give surface fog nuclei using light or a nucleating agent after image exposure. As the nucleating agent therefor, hydrazines described in US Pat. Nos. 2,563,785 and 2,588,982, hydrazines and hydrazones described in US Pat. No. 3,227,552, UK Patent 1,283,835, JP-A-52-69613, US Patent 3,615,615, 3,719,494, 3,734,738, 4,094,683, Heterocyclic quaternary salt compounds described in U.S. Pat. No. 4,115,122, and sensitizing dyes having a nucleating substituent described in U.S. Pat. No. 3,718,470 in dye molecules, U.S. Pat. , 030,925, 4,031,127, 4,245,037, 4,255,511, 4,266,013, 4,276,364, British Patent 2, 012,443 etc. Thiourea-linked acylhydrazine compounds and heterocyclic groups such as thioamide rings, triazoles, and tetrazoles described in US Pat. Nos. 4,080,270, 4,278,748, British Patent 2,011,391B, etc. An acyl hydrazine-based compound in which is bonded as an adsorbing group is used.

  In the present invention, a spectral sensitizing dye can be used in combination with these negative emulsion and internal latent image type direct positive emulsion. Specific examples thereof include JP-A-59-180550, JP-A-60-140335, Research Disclosure (RD) 17029, U.S. Pat. No. 1,846,300, JP-A-2,078,233, JP-A-2,089, No. 129, No. 2,165,338, No. 2,231,658, No. 2,917,516, No. 3,352,857, No. 3,411,916, No. 2,295,276 2,481,698, 2,688,545, 2,921,067, 3,282,933, 3,397,060, 3,660,103, 3,335,010, 3,352,680, 3,384,486, 3,623,881, 3,718,470, 4,025,349, etc. ing.

(3) Structure of photosensitive layer The above-described dye image-forming compound which provides a dye having a selective spectral absorption in the same wavelength range as that of the emulsion spectrally sensitized by the spectral sensitizing dye for reproducing a natural color by the subtractive color method And a photosensitive layer comprising at least two of the combinations.
In the halogenated emulsion layer combined with the dye image-forming substance, the emulsion and the dye image-forming compound may be coated as separate layers, or may be mixed and coated as a single layer. When the dye image-forming compound is coated and has absorption in the spectral sensitivity range of the emulsion combined therewith, a separate layer is preferred. The emulsion layer may be composed of a plurality of emulsion layers having different sensitivities, and an arbitrary layer may be provided between the emulsion layer and the dye image forming compound layer. For example, a layer containing a nucleation development accelerator described in JP-A-60-173541, a partition layer described in JP-B-60-15267 is provided to increase the color image density, or a reflective layer is formed. The sensitivity of the provided photosensitive element can also be increased.

In the multilayer structure of the photosensitive layer in the present invention, it is preferable that the combination unit of the blue-sensitive emulsion, the combination unit of the green-sensitive emulsion, and the combination unit of the red-sensitive emulsion are sequentially arranged from the exposure side. Arbitrary layers can be provided between the respective emulsion layer units as required. In particular, it is preferable to provide an intermediate layer in order to prevent the undesired influence of the development effect of a certain emulsion layer on other emulsion layer units.
In the present invention, an irradiation prevention layer, a UV absorber layer, a protective layer and the like are coated as necessary.
The thickness of the photosensitive layer in the present invention is not particularly limited.

  Each layer on the transparent support of the photosensitive sheet in the present invention can be installed by an ordinary coating method. Further, the thickness of the entire photosensitive sheet is not particularly limited.

II. Transparent cover sheet In the color diffusion transfer film unit of the present invention, a transparent cover sheet having a neutralization layer and a neutralization timing layer on a support is used.
F) Support The support of the cover sheet used in the present invention may be any smooth transparent support that is usually used for photographic materials, such as cellulose acetate, polystyrene, polyethylene terephthalate, and polycarbonate. To mention. It is preferable to provide an undercoat layer on the transparent support. The support preferably contains a trace amount of dye to prevent light piping.

G) Layer having a neutralization function The layer having a neutralization function (neutralization layer) used in the present invention contains an acidic substance in an amount sufficient to neutralize the alkali introduced from the alkali treatment composition described later. In addition to the neutralization rate adjusting layer (neutralization timing layer), it may have a multilayer structure composed of layers such as an adhesion reinforcing layer as necessary.
A preferable acidic substance is a substance containing an acidic group having a pKa of 9 or less (or a precursor group that gives such an acidic group by hydrolysis), and more preferably described in US Pat. No. 2,983,606. Higher fatty acids such as oleic acid, polymers of acrylic acid, methacrylic acid or maleic acid as disclosed in US Pat. No. 3,362,819 and partial esters or anhydrides thereof; , 290,699, a copolymer of acrylic acid and an acrylate ester; U.S. Pat. No. 4,139,383 and Research Disclosure No. Mention may be made of latex-type acidic polymers as disclosed in US Pat. No. 16102 (1977). In addition, U.S. Pat. No. 4,088,493, JP-A-52-153739, 53-1023, 53-4540, 53-4541, 53-4542, etc. Also disclosed are acidic substances disclosed in.

  Specific examples of the acidic polymer (polymer acid) as the acidic substance include a copolymer of vinyl monomer such as ethylene, vinyl acetate, vinyl methyl ether, and maleic anhydride, and an n-butyl ester, butyl acrylate, and acrylic. Examples thereof include a copolymer with an acid, cellulose, and acetate / hydrodiene phthalate.

The acidic polymer can be used as a mixture with a hydrophilic polymer. Examples of such hydrophilic polymers include polyacrylamide, polymethylpyrrolidone, polyvinyl alcohol (including partially saponified products), carboxymethyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, polymethyl vinyl ether, and the like. Of these, polyvinyl alcohol is preferred.
Further, a polymer other than the hydrophilic polymer such as cellulose acetate may be mixed with the acidic polymer.

  The coating amount of the polymer acid is adjusted by the amount of alkali in the alkali treatment composition described later. The equivalent ratio of polymer acid to alkali per unit area is preferably 0.9 to 2.0. If the amount of the polymer acid is too small, the hue of the transfer dye changes or stains are produced in the white background, and if it is too much, problems such as a change in hue or a decrease in light resistance occur. A more preferred equivalent ratio is 1.0 to 1.3. If the amount of the hydrophilic polymer to be mixed is too large or too small, the quality of the photograph is deteriorated. The mass ratio of the hydrophilic polymer to the polymer acid is 0.01 to 10, preferably 0.1 to 3.0.

  Additives can be incorporated into the layer having a neutralizing function in the present invention for various purposes. For example, hardeners well known to those skilled in the art to harden this layer, or polyhydric hydroxyl compounds such as polyethylene glycol, polypropylene glycol, glycerin, etc., can be added to improve the brittleness of the film. In addition, an antioxidant, a fluorescent brightening agent, a development inhibitor, and a precursor thereof can be added as necessary.

  In the present invention, the neutralization timing layer used in combination with the neutralization layer is, for example, gelatin, polyvinyl alcohol, partially acetalized polyvinyl alcohol, cellulose acetate, partially hydrolyzed polyvinyl acetate, or the like. Polymers that lower alkali permeability; latex polymers that are made by copolymerizing a small amount of a hydrophilic comonomer such as an acrylic acid monomer and that increase the activation energy of alkali permeation; polymers that have a lactone ring are useful.

  Of these, cellulose acetate disclosed in JP-A-54-136328, U.S. Pat. No. 4,267,262, U.S. Pat. No. 4,009,030, U.S. Pat. Timing layer: JP-A-54-128335, JP-A-56-69629, JP-A-57-6843, US Pat. Nos. 4,056,394, 4,061,496, 4,199, No. 362, No. 4,250,243, No. 4,256,827, No. 4,268,604, etc. are copolymerized with a small amount of a hydrophilic comonomer such as acrylic acid. Latex polymer prepared; polymer having monoacrylic acid ester or monomethacrylic acid ester of polyhydric alcohol disclosed in JP-A-11-2890 Polymers having a lactone ring disclosed in U.S. Pat. No. 4,229,516; other JP-A-56-25735, JP-A-56-97346, JP-A-57-6842, European Patent (EP) 31, The polymers disclosed in 957A1, 37,724A1, 48,412A1, etc. are particularly useful.

In addition, those described in the following documents can also be used.
U.S. Pat. Nos. 3,421,893, 3,455,686, 3,575,701, 3,778,265, 3,785,815, 3,847 No. 4,615, No. 4,088,493, No. 4,123,275, No. 4,148,653, No. 4,201,587, No. 4,288,523, No. 4,297,431, West German Patent Application (OLS) No. 1,622,936, No. 2,162,277, Research Disclosure 15162, no. 151 (1976).
The neutralization timing layer using these materials can be used as a single layer or as a combination of two or more layers.

  Further, for example, US Pat. No. 4,009,029, West German Patent Application (OLS) 2,913,164, US Pat. 54-155837, 55-138745, etc., development inhibitors and / or precursors thereof, hydroquinone precursors disclosed in US Pat. No. 4,201,578, and other useful photographs. It is also possible to incorporate additives for use or precursors thereof. Furthermore, providing a neutralizing layer as described in JP-A Nos. 63-168648 and 63-168649 as the layer having the neutralizing function reduces the change in transfer density over time after processing. This is effective.

H) Others The cover sheet in the present invention may have a back layer, a protective layer, a filter dye layer, and the like as a layer having an auxiliary function in addition to the layer having a neutralizing function.
The back layer is provided for adjusting curl and imparting slipperiness. Filter dyes may be added to this layer.
The protective layer is mainly used to prevent adhesion to the cover sheet back surface and adhesion to the photosensitive material protective layer when the photosensitive material and the cover sheet are overlapped. The sensitivity of the photosensitive layer can be adjusted by incorporating a dye into the cover sheet.
The filter dye may be added directly to the support of the cover sheet or the layer having a neutralizing function, and further to the back layer, protective layer, capture mordant layer, etc., or a single layer may be provided. .

  Each layer on the support of the transparent cover sheet in the present invention can be installed by a usual coating method. Moreover, the thickness of the whole transparent cover sheet is not specifically limited.

III. Alkali Processing Composition In the present invention, the alkali processing composition is a light-shielding layer that is uniformly spread between a photosensitive sheet and a transparent cover sheet after exposure of a photosensitive sheet (hereinafter also referred to as a photosensitive element), and is disposed on the photosensitive sheet. In other words, the photosensitive layer is completely shielded from external light, and at the same time, the photosensitive layer is developed with the components contained therein. For this purpose, the composition contains an alkali, a thickener, a light-shielding agent, a developer, a development accelerator for controlling development, a development inhibitor, and an antioxidant for preventing deterioration of the developer. Etc. A light-shielding agent is always included in the composition for light-shielding. As the light-shielding agent, the light-shielding agent used in the light-shielding layer of the photosensitive sheet can be used, and carbon black is preferable.

These alkali processing compositions are preferably developed on the photosensitive element with a development thickness (a processing liquid amount per m ² after transferring the processing liquid) of 10 μm to 200 μm. The processing temperature when processing the photosensitive element is preferably 0 to 50 ° C, more preferably 0 to 40 ° C.

  The alkali is sufficient to adjust the pH of the liquid to 12 or more, such as an alkali metal hydroxide (for example, sodium hydroxide, potassium hydroxide, lithium hydroxide), an alkali metal phosphate (for example, potassium phosphate). , Guanidines and hydroxides of quaternary amines (for example, tetramethylammonium hydroxide), among which potassium hydroxide and sodium hydroxide are preferable.

  The thickener is necessary to uniformly develop the processing composition and to maintain adhesion between the photosensitive layer / cover sheet. For example, an alkali metal salt of polyvinyl alcohol, hydroxyethyl cellulose, or carboxymethyl cellulose is used, and preferably hydroxyethyl cellulose or sodium carboxymethyl cellulose is used. As the light-shielding agent, any dye or pigment or a combination thereof may be used as long as it does not diffuse to the dye image-receiving layer and produce stain. A typical example is carbon black.

  As the preferred developer, any developer can be used as long as it cross-oxidizes the dye image-forming compound and does not substantially produce stain even when oxidized. Such developing agents may be used alone or in combination of two or more, or may be used in the form of a precursor. These developing agents may be contained in an appropriate layer of the photosensitive sheet or in the alkaline processing composition. Specific examples of the compound include aminophenols and pyrazolidinones. Among them, pyrazolidinones are particularly preferable because they generate less stain. For example, 1-phenyl-3-pyrazolidinone, 1-p-tolyl-4,4-dihydroxymethyl-3-pyrazolidinone, 1- (3′-methyl-phenyl) -4-methyl-4-hydroxymethyl-3-pyrazolidinone 1-phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidinone, 1-p-tolyl-4-methyl-4-hydroxymethyl-3-pyrazolidinone, and the like.

A development accelerator described in JP-A-62-215272, pages 72 to 91, a hardener described in pages 146 to 155, or a surfactant described in pages 201 to 210, in any one of a photosensitive sheet, a cover sheet and an alkali processing composition. A fluorine-containing compound described on pages 210-222, a thickener described on pages 225-227, an antistatic agent described on pages 227-230, a polymer latex described on pages 230-239, a matting agent described on page 240, and the like. Can do. Further, tertiary amine latexes described in JP-A-6-273907, JP-A-7-134386, JP-A-7-175193, and JP-A-7-287372 can be included.
The thickness of the diffusion transfer film unit of the present invention is not particularly limited.

  In the present invention, in order to arrange the photosensitive sheet, the transparent cover sheet, and the alkali treatment composition so as to be exposed through the transparent cover sheet, for example, the method described in JP-A-2001-249436 can be performed. it can.

  A preferred exposure method applied to the diffusion transfer film unit in the present invention is a method of exposing using an exposure head having different light sources that emit light in a plurality of specific wavelength regions.

EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to this.
Example 1

1. Preparation of Photosensitive Sheet First, each layer having the composition shown in Tables 1 to 4 below was coated according to a conventional method to prepare a photosensitive element (photosensitive sheet-101). The emulsions in the table were prepared by the method shown in Table 5.

  The compound used for preparation of the photosensitive element (Photosensitive sheet-101) is shown below.

2. Production of Cover Sheet A polyethylene sheet having a thickness of 75 μm was coated on a transparent transparent support of polyethylene terephthalate to form a cover sheet 101 as shown in Table 6.

  The chemical structural formulas and the like of the compounds used in the cover sheet are shown below.

3. Production of Alkali Treatment Composition Next, an alkali treatment composition (treatment liquid-101) having the following composition was produced.
Carbon black (manufactured by Dainichi Seika Co., Ltd.) 224.3 g
Additive (23) 12.1 g
Carboxymethylcellulose Na salt 43.0 g
Potassium sulfite (anhydrous) 1.90 g
1-phenyl-4-hydroxymethyl-4-methyl-3-pyrazolidone 13.6 g
Potassium hydroxide 52.7 g
Zinc nitrate 0.60g
Water was added in a total amount of 1 kg. Each treatment solution having the above composition was filled in a container capable of being broken by pressure in an amount of 0.3 g.

  Next, photosensitive sheet 102 and 103 were prepared by reducing the coating amount of the second layer of photosensitive sheet 101 to 80% and 50%, respectively. Further, only the gelatin coating amount of the second layer of the photosensitive sheet 101 was reduced to prepare the photosensitive sheet 104. Further, only the coating amount of titanium dioxide in the second layer of the photosensitive sheet 101 was reduced to prepare the photosensitive sheet 105. Furthermore, in order to return the film thickness of the second layer of the photosensitive sheet 103 to the same level as the photosensitive sheet 101, the following commercially available aqueous dispersions of spherical fine particles were added as spacers to prepare photosensitive sheets 106 to 112. Tables 7 and 8 show the coating amount of each additive in the second layer (sample) of each photosensitive sheet.

Fine particle dispersion Manufacturer Product name Average particle size Solid mass%
Fine particle aqueous dispersion 1 JSR SX866 0.3μm Solid content 20%
Fine particle aqueous dispersion 2 SX8743-03 0.3 μm, solid content 20%, manufactured by JSR
Fine particle aqueous dispersion 3 SX8743-05 from JSR 0.5 μm Solid content 15%
Fine particle dispersion 4 Nippon Shokubai MX100W 0.14μm Solid content 10%
Fine particle water dispersion 5 KE-W10 0.09μm solid content 16%
Fine particle aqueous dispersion 6 Nippon Shokubai KE-W30 0.30μm Solid content 20%
Fine particle water dispersion 7 Nippon Shokubai KE-W50 0.50μm Solid content 20%
In addition, the coating amount of the fine particle dispersion in Tables 7 and 8 is shown as the coating amount of the solid content.

In Sample 103, samples in which the coating amount of the fine particle aqueous dispersion 7 was changed to 0.3 g / m 3 and 8.3 g / m 3 were prepared, and Samples 114 and 115 were obtained, respectively.
Color diffusion transfer film units -101 to 113 were prepared using the photosensitive sheets -101 to 115, the cover sheet -101 and the processing solution -101 based on the method described in JP-A-7-159931. After this color diffusion transfer film unit is loaded into the camera, it is exposed from the cover sheet side and developed by a pressure roller adjusted so that the processing liquid has a thickness of 55 μm between both materials. Exposure and development were performed. The treatment was performed at 25 ° C., and the thickness of the white light diffusion layer was measured for the sample one day after the development treatment. Subsequently, the reflection density was measured with a color densitometer, and the maximum density (Dmax) and the minimum density (Dmin) were obtained. Further, the image forming speed was measured. Table 9 shows the measured values of the cyan density. The value of Dmax was omitted because there was no change.

The thickness of the white light diffusing layer was measured by cutting out a cross section in the thickness direction of the sample after treatment with a microtome and observing it with an optical microscope. Further, the surface shape was observed visually, and a sample having NG of 1 / cm ² or more of spot-like color development on a white background was defined as NG.

The image forming speed was measured as follows. When the color diffusing units 101 to 115 are exposed and developed, the cyan density is measured over time for the portion exposed at an exposure amount giving the maximum density (Dmax) of the characteristic curve immediately after the completion of the development. The time required to exceed 0 was examined. This required time is hereinafter referred to as transfer speed. Moreover, Dmin after drying for 1 month on 25 degreeC55% conditions was measured.
Table 9 summarizes the above results.

Table 9 shows the following.
From the comparison of the units 101 to 103, if both the titanium oxide fine particles and the gelatin are simultaneously reduced, the transfer speed increases, but the density of Dmin increases and the white background deteriorates. Regarding the whiteness, a difference of 0.01 can be recognized with eyes. From the comparison of the units 101 and 104, if only the gelatin of the white light diffusion layer is reduced, the Dmin is low and the transfer speed is fast, but after processing, a small spot-like image defect is scattered on the white background part and is not allowed as a product surface shape. It was planar. From the comparison of the units 101 and 105, when the titanium dioxide in the white diffusion layer was reduced, the white background density after the treatment day was an acceptable level, but the white background density after one month increased to an unacceptable level. Moreover, although the transfer speed was slightly increased, it was a level that required further improvement. In the unit 106 in which the coating amounts of titanium dioxide and gelatin in the white light diffusing layer are increased 1.33 times from the unit 105, the density of the white background reaches an allowable level, but the transfer speed is significantly delayed.
From the above, it is necessary to keep the titanium dioxide / gelatin mass ratio of the white light diffusing layer at 10 or less in order to obtain an acceptable surface shape, but the amount of titanium dioxide can be reduced to obtain an acceptable white background. Absent. Accordingly, since the amount of gelatin applied cannot be reduced, the density of the white background and the transfer speed are in a trade-off relationship.
On the other hand, the units 107 to 113 according to the present invention using the fine particle dispersion can significantly improve the transfer speed while maintaining the white background density by removing from the above relationship. From the comparison of the units 113, 114, 115, and 103, when the mass ratio represented by titanium dioxide: spacer fine particles is 10: 1 or less, sufficient whiteness cannot be obtained. It can be seen that it is.

Example 2
In the color diffusion transfer photographic unit production method of Example 1, the photosensitive element was changed to the photosensitive sheet-201, and a unit in which the developed thickness of the processing solution was changed was produced, and the effect was evaluated.

  First, photosensitive elements (photosensitive sheet-201) having the compositions shown in Tables 10 to 14 below were prepared.

  The compound used for preparation of the photosensitive element (photosensitive sheet-201) is shown below.

  Three types of silver halide emulsions, surface latent image type emulsions -J, K, and L, were prepared by the following preparation method and used. Table 15 summarizes the results.

Emulsion-K:
In 0.7 liter of gelatin aqueous solution containing 1.1 g of low molecular weight gelatin having 0.005 mol of potassium bromide and an average molecular weight of 20,000 or less, 26.5 ml of silver nitrate aqueous solution having a concentration of 0.58 mol / liter and 0.42 mol of potassium bromide 46.4 ml of an aqueous solution containing 1.5% by weight of a low molecular weight gelatin having an average molecular weight of 20,000 or less was mixed at the same time by virtue of the double jet method over 1 minute (first addition). During this period, the gelatin aqueous solution was kept at 35 ° C. After adding 0.5 g of potassium bromide, the temperature was raised to 75 ° C. with a gradient of 1.5 ° C. per minute.
After reaching a temperature of 75 ° C., 0.16 liters of gelatin solution containing 16% by mass of deionized gelatin having a Ca content of 100 ppm or less (first addition) and 5 ml of 4.9% sulfuric acid aqueous solution were added. Subsequently, a double jet at an accelerated flow rate (the flow rate at the end is 3.5 times the flow rate at the start) of a silver nitrate aqueous solution having a concentration of 1.88 mol / liter and a potassium bromide aqueous solution having a concentration of 1.88 mol / liter. (The second addition, the amount of silver nitrate aqueous solution used was 366 ml, and the amount of potassium bromide aqueous solution was 375 ml).

  Next, 0.08 liter of gelatin solution containing 14% by mass of deionized gelatin having a Ca content of 100 ppm or less (second addition) and 2 mg of sodium benzenethiosulfate were added. Subsequently, an aqueous solution of silver nitrate with a concentration of 1.88 mol / liter and an aqueous solution of potassium bromide with a concentration of 1.88 mol / liter are double jetted at an accelerated flow rate (the flow rate at the end is 1.2 times the flow rate at the start). (Added for the third time, the amount of silver nitrate aqueous solution used was 157 ml, and the amount of potassium bromide aqueous solution was 163 ml).

After adding 4.6 g of potassium bromide, it was washed with water by a conventional flocculation method, deionized gelatin, 2-phenoxyethanol and methyl p-hydroxybenzoate were added, and then adjusted to pH 5.8 and pAg 8.8. The emulsion was adjusted to contain 1.35 mol of silver and 84 g of gelatin per 1 kg of the emulsion. 0.74 kg of the emulsion thus prepared was dissolved by heating and heated to 55 ° C., then 0.5 g of potassium iodide, 4.2 × 10 ⁻⁴ mol of sensitizing dye (6), and sensitizing dye. 5.4 × 10 ⁻⁴ mol of (7) was added and aging was performed for 30 minutes. Next, 5.0 × 10 ⁻⁴ mol of potassium thiocyanate, 1.4 × 10 ⁻⁵ mol of potassium tetrachloroaurate, and 1.2 × 10 ⁻⁵ mol of sodium thiosulfate were added and aged for 60 minutes. Emulsion preparation was completed by adding 1.0 × 10 ⁻³ mol of Compound E-4 and further adding 3.2 × 10 ⁻⁴ mol of Compound E-5 at the end of ripening.

  The diameter of a circle having an area equal to the projected area when viewed from the main plane direction of each particle is called a circle equivalent diameter. As a result of observation by an electron microscope, the average value of the particle thickness hi (= Σhi × ni / Σni) was 0.135 μm, and the average value of the equivalent circle diameter Di of the particles (= ΣDi × ni / Σni) was 1.15 μm. The average aspect ratio defined by the average value of the equivalent circle diameter Di / the average value of the particle thickness hi was 8.5.

Emulsion-J:
Emulsion-J was prepared by adding 9.2 × 10 ⁻⁴ mol of sensitizing dye (9) instead of sensitizing dye (6) and sensitizing dye (7) in the preparation method of emulsion-K. .

Emulsion-L:
In the preparation method of Emulsion-K, sensitizing dye (1) is 8.4 × 10 ⁻⁴ mol instead of sensitizing dye (6) and sensitizing dye (7), and sensitizing dye (2) is 2.6. Emulsion-L was prepared by adding .times.10.sup.- ⁵ mol and sensitizing dye (3) to 1.7.times.10.sup.- ⁴ mol.

  The compounds used for the emulsion preparation are summarized below.

  Sample No. 2 shown in Tables 7 to 8 in Example 1 was applied to the second white light diffusion layer. Photosensitive sheets 202 to 213 were prepared in the same manner as the photosensitive sheet 201 except that they were changed to 102 to 113, respectively.

Based on the method described in JP-A-7-159931 using the photosensitive sheets 201 to 213, the cover sheet 101 and the processing solution 101 in Example 1, color diffusion transfer film units 201 to 213 are prepared. Produced. This color diffusion transfer film unit was subjected from exposure to development processing with an exposure development processing machine incorporating a three-color LED exposure machine of blue, green and red. After loading the color diffusion transfer film unit-201 to 213 into the exposure development processing machine, exposure is performed using an LED as a light source from the cover sheet side, and a pressure roller adjusted so that the processing liquid has a thickness of 38 μm between both materials. The unit-201 to 213 were exposed and developed. The treatment was performed at 25 ° C., and after 5 minutes from the development treatment, the reflection density after 1 day was measured with a color densitometer to obtain the maximum density and the minimum density.
Further, in the same manner as in Example 1, the thickness of the white light diffusion layer, the surface shape, and the Dmin of the cyan density after drying for one month were also measured.
The results are shown in Table 16.

The results in Table 15 can be interpreted in exactly the same way as in Example 1, indicating the effectiveness of the present invention.
From the comparison of the units 201 to 203, when both the titanium oxide fine particles and the gelatin are simultaneously reduced, the transfer speed increases, but the density of Dmin increases and the white background deteriorates. As described in the first embodiment, regarding the whiteness, a difference of 0.01 in Dmin can be recognized with eyes. From the comparison between the units 201 and 204, when only the gelatin of the white light diffusion layer is reduced, the Dmin is low and the transfer speed is fast. However, after processing, a small spot-like image defect is scattered on the white background part and is not allowed as a product surface shape. It was planar. From the comparison between the units 201 and 205, when the titanium dioxide in the white light diffusing layer was reduced, the white background density after the treatment day was an acceptable level, but the white background density after one month was increased to an unacceptable level. Moreover, although the transfer speed was slightly increased, it was a level that required further improvement. In the unit 206 in which the coating amounts of titanium dioxide and gelatin in the white light diffusing layer are increased 1.33 times from the unit 205, the density of the white background reaches an allowable level, but the transfer speed is significantly delayed.
From the above, it is necessary to keep the titanium dioxide / gelatin mass ratio of the white light diffusing layer at 10 or less in order to obtain an acceptable surface shape, but the amount of titanium dioxide can be reduced to obtain an acceptable white background. Absent. That is, it can be seen that the white background density and the transfer speed are in a trade-off relationship.
On the other hand, the units 206 to 212 according to the present invention using the fine particle dispersion can significantly improve the transfer speed while maintaining the white background density by removing from the above relationship.

Claims (4)

Photosensitive sheet having an image receiving layer on a transparent support, a white light diffusing layer containing titanium dioxide fine particles dispersed in gelatin, a light shielding layer, and a silver halide emulsion layer combined with a dye image forming material, and a support A transparent cover sheet having a neutralization layer and a neutralization timing layer thereon, and a light-shielding agent-containing alkaline treatment composition developed after exposure between the photosensitive sheet and the transparent cover sheet, and these are transparent A diffusion transfer film unit disposed so as to be exposed through a cover sheet, wherein a titanium dioxide / gelatin mass ratio in a white light diffusion layer provided between an image receiving layer and a light shielding layer in the photosensitive sheet is 10 or less And the gelatin content of the white light diffusion layer is 1.7 g / m ² or less, and the white light diffusion layer further contains spacer fine particles, A diffusion transfer film unit, wherein a mass ratio of titanium dioxide fine particles and spacer fine particles in the light diffusion layer expressed by titanium dioxide: spacer fine particles is 10: 1 to 10: 5.   The diffusion transfer film unit according to claim 1, wherein the spacer fine particles are organic polymer fine particles.   The diffusion transfer film unit according to claim 1, wherein the spacer fine particles are silica fine particles.   The diffusion transfer film unit according to any one of claims 1 to 3, wherein the diffusion transfer film unit is exposed using an exposure head having different light sources that emits light in a plurality of specific wavelength regions.