Arai, Atsuaki (Kanagawa, JA)
Oishi, Yasushi (Kanagawa, JA)
Yamada, Minoru (Kanagawa, JA)
Furutachi, Nobuo (Kanagawa, JA)
Nakamura, Kotaro (Kanagawa, JA)

05/461204

12/16/1975

04/15/1974

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Fuji Photo Film Co., Ltd. (Minami-ashigara, JA)

430/226

430/555, 430/381, 430/241, 430/548, 430/387, 430/372

G03C7/384; G03C7/38; G03C1/40; G03C5/54

96/100,74,9,56,29D,56.5

Brown, Travis J.

Sughrue, Rothwell, Mion, Zinn & Macpeak

What is claimed is

1. A light-sensitive silver halide emulsion containing a coupler having the General Formula (I) or (II) ##SPC9##

2. The light-sensitive silver halide emulsion of claim 1, wherein said light-sensitive silver halide emulsion contains a p-substituted phenol in an effective amount to stabilize the dye image formed upon development with an aromatic primary amino color developing agent.

3. The light-sensitive silver halide emulsion of claim 2, wherein said p-substituted phenol is a hydroquinone derivative, a gallic acid derivative, a p-alkoxyphenol or a p-oxyphenol.

4. The light-sensitive silver halide emulsion of claim 3, wherein said p-substituted phenol is a p-oxyphenol.

5. The light-sensitive silver halide emulsion of claim 3, wherein said p-substituted phenol is a hydroquinone derivative having a hydrophobic residue containing about 8 to 18 carbon atoms.

6. The light-sensitive silver halide emulsion of claim 3, wherein said p-substituted phenol is a 5-hydroxycoumaran, a 6-hydroxy coumaran, or a 6,6'-dihydroxyspirochroman.

7. The light-sensitive silver halide emulsion of claim 6, wherein said light sensitive silver halide emulsion contains a hydroquinone derivative.

8. The light-sensitive silver halide emulsion of claim 1, wherein said silver halide emulsion contains additionally a 4-equivalent 5-pyrazolone compound in which the 4-position is unsubstituted and/or a colored magenta coupler.

9. A light-sensitive photographic element comprising a support having thereon at least one light-sensitive layer comprising a hydrophilic colloid silver halide emulsion having dispersed therein an uncolored dye image forming two equivalent coupler selected from the group consisting of the couplers represented by the General Formula (I) and (II) ##SPC10## ##SPC11##

10. The light-sensitive photographic element of claim 9, wherein said light-sensitive element contains a p-substituted phenol in an effective amount to stabilize the dye image formed upon development with an aromatic primary amino color developing agent.

11. The light-sensitive photographic element of claim 10, wherein said p-substituted phenol is a hydroquinone derivative, a gallic acid derivative, a p-alkoxyphenol or a p-oxyphenol.

12. The light-sensitive photographic element of claim 11, wherein said p-substituted phenol is a p-oxyphenol.

13. The light-sensitive photographic element of claim 11, wherein said p-substituted phenol is a hydroquinone derivative having a hydrophobic residue containing about 8 to 18 carbon atoms.

14. The light-sensitive photographic element of claim 11, wherein said p-substituted phenol is a 5-hydroxycoumaran, a 6-hydroxycoumaran, or a 6,6'-dihydroxyspirochroman.

15. The light sensitive photographic element of claim 14, wherein said light-sensitive photographic element contains a hydroquinone derivative.

16. The light-sensitive photographic element of claim 9, wherein said silver halide emulsion contains additionally a 4-equivalent 5-pyrazolone compound in which the 4-position is unsubstituted and/or a colored magenta coupler.

17. A process of forming a color image which comprises developing a silver halide photographic emulsion with an aromatic primary amine as a color developing agent in the presence of a coupler as defined in claim 1.

18. A process of forming a color image which comprises developing an exposed silver halide photographic emulsion with an alkaline aqueous solution containing an aromatic primary amine color developing agent in the presence of a magenta-forming coupler represented by General Formula (I) or (II) ##SPC12##

19. A process of forming a color image which comprises exposing a light-sensitive material comprising a support having thereon a silver halide photographic emulsion layer containing a magenta-forming coupler represented by General Formula (I) or (II) ##SPC13##

20. A process of forming a color image which comprises developing a light-sensitive material comprising a support having thereon a silver halide photographic emulsion layer in combination with a magenta-forming coupler having the General Formula (I) or (II) ##SPC14##

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to color photography and more particularly, it is concerned with a novel magenta coupler useful for forming a color image in color photography and a silver halide color photographic material containing the same.

2. Description of the Prior Art

It is known that, by the color development of a silver halide color photographic material, a color developing agent of aromatic primary amine type is oxidized and is reacted with a coupler to form a dye, such as indophenols, indoanilines, indamines, azomethines, phenoxazines, phenazines and the like, thus forming a color image. In this type, the subtractive color process is ordinarily used for color reproduction and yellow, magenta and cyan color images are formed, which are respectively the complementary colors of blue, green and red. For example, a coupler of the acylacetanilide or dibenzoylmethane type is used for forming a yellow color image, a coupler of the pyrazolone, cyanoacetophenone or indazolone type is used for forming a magenta color image and a coupler of the phenol type, such as a phenol and a naphthol, is used for forming a cyan color image.

In such photography, a coupler forming a dye is added to a developer or incorporated in a light-sensitive photographic emulsion layer. Therefore, an oxidized color developing agent, which is formed when a latent image is developed, is reacted with the coupler to form a color image.

The color image-forming couplers of the prior art are almost all four equivalent couplers which require theoretically four mols of silver halide as an oxidizer for forming 1 mol of the dye through the coupling reaction. On the contrary, a two equivalent coupler having an active methylene group which is substituted by a group capable of being split off through the coupling of an oxidized product of the developing agent consisting of an aromatic primary amine requires only the development of two mols of silver halide for forming 1 mol of the dye. Since the quantity of silver halide required for forming a dye in the case of a two equivalent coupler is one half of that required in the case of an ordinary four equivalent coupler, the two-equivalent coupler has many advantages in that a thinner light-sensitive layer can be used and the layer can be processed rapidly. In addition, the photographic properties and economy can be increased through a reduction in the film thickness.

In particular, a two-equivalent magenta coupler has been desired because generally a higher coupler to dye conversion ratio is obtained than the four equivalent coupler and less influence upon the fading of a color image due to remaining of the coupler is exhibited. However, the hitherto proposed two equivalent couplers have various disadvantages in that the reactivity is not suitable, staining and fogging occur and there are many difficulties in synthesizing the couplers.

Therefore, it is a first object of the invention to provide a new two equivalent pyrazolone magenta coupler, in which the 4-position of the 5-pyrazolone nucleus is substituted with a group capable of being released by the coupling reaction with an oxidation product of an aromatic primary amine developing agent.

It is a second object of the invention to provide a new two equivalent coupler having a suitable reactivity and being capable of forming a colored dye with a high yield and without forming undesired stains and fogs.

It is a third object of the invention to provide a color photographic light-sensitive material having a silver halide emulsion layer containing a new magenta color image forming coupler.

It is a fourth object of the invention to provide an improved color photographic process whereby the quantity of silver halide in the photographic emulsion layer is reduced and the sharpness of a color image is improved by the use of a new magenta color image forming coupler.

It is a fifth object of the invention to provide a color photograph having a durable color image by the use of a new magenta color image forming coupler.

Still additional objects will be apparent from the following description of the invention and the accompanying drawing.

SUMMARY OF THE INVENTION

We, the inventors, have made various efforts to accomplish the above described objects and have found that the color image formed is very excellent when a silver halide photographic emulsion is treated with an aromatic primary amine developing agent in the presence of a magenta color image forming coupler in which the 4-position of the 5-pyrazolone ring is substituted with a carbonic ester group or an oxalic ester group.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING

The drawing is a graph showing that Film A of the invention is superior to Film B of the prior art in obtaining a constant color image with a small quantity of developed silver required.

DETAILED DESCRIPTION OF THE INVENTION

In the present invention, any of the 5-pyrazolones can be used without difficulties, in which the 4-position of the pyrazolone ring is substituted with a carbonic ester group or an oxalic ester group. That is to say, any of the pyrazolones in which the 4-position of the 5-pyrazolone used as a four equivalent magenta coupler has a carbonic ester bond or an oxalic ester bond and any pyrazole-4,5-diesters derived from the enol type of the 5-pyrazolones can be used without difficulty.

These compounds can be represented, for example, by the following General Formulas (I) and (II): ##SPC1## ##SPC2##

in which R ₁ and R ₂ represent conventional groups such as are used in four equivalent pyrazolone couplers, R ₃ represents a monovalent group, R ₄ represents a divalent group and n represents 0 or 1.

For example, R ₁ is a hydrogen atom or a group of 1 to about 50 carbon atoms, preferably 1 to 35 carbon atoms, i.e., a straight chain or branched chain alkyl group such as a methyl, ethyl, i-propyl, tert-butyl, hexyl, tert-octyl or dodecyl group; an alkenyl group such as an allyl group; a cycloalkyl group such as a cyclohexyl or norbornyl group; a substituted alkyl or cycloalkyl group containing as a substituent, a halogen atom or a nitro, cyano, aryl, alkoxy, aryloxycarboxy, alkoxycarbonyl, aryloxycarbonyl, sulfo, sulfamoyl, carbamoyl, acylamino, ureido, arylsulfonyloxy or oxo group, for example, β-cyanoethyl, β-chloroethyl, benzyl, nitrobenzyl, dichlorobenzyl, γ-(2,4-di-tert-amylphenoxy)-propyl or β-phenoxyethyl group. Furthermore, R ₁ is an aryl group such as a phenyl or an α- or β-naphthyl group; an aryl group having one or more substituents such as alkyl, alkoxy, aryloxy, carboxy, alkoxycarbonyl, acylamino, carbamoyl, alkylcarbamoyl, dialkylcarbamoyl, arylcarbamoyl, alkylsulfonamide, arylsulfonamide, sulfamoyl, alkylsulfamoyl, cyano and nitro groups or halogen atoms. A phenyl group in which at least one of the ortho-positions is substituted with an alkyl group, an alkoxy group or a halogen atom is particularly useful as R ₁ . Furthermore, R ₁ represents a heterocyclic group such as 5-membered or 6-membered heterocyclic group or condensed heterocyclic group containing, as a hetero-atom, a nitrogen, oxygen or sulfur atom, for example, pyridyl, quinolyl, furyl, benzothiazolyl, oxazolyl, imidazolyl or naphthoxazolyl group, or a substituted heterocyclic group with the substituents above described for the aryl group. Furthermore, R ₁ represents a carbamoyl or thiocarbamoyl group.

R ₂ represents a group having 1 to about 50 carbon atoms, preferably 1 to 35 carbon atoms, i.e., the same alkyl, substituted alkyl, aryl, substituted aryl, heterocyclic group or substituted heterocyclic group as described for R ₁ . Furthermore, R ₂ represents an alkoxycarbonyl group such as a methoxycarbonyl or ethoxycarbonyl group; an aryloxycarbonyl group; an aralkyloxycarbonyl group; substituted oxy group such as an alkoxy group, e.g., methoxy, ethoxy, decycloxy, etc., or an aryloxy group, e.g., a phenoxy, tolyloxy, etc.; a substituted thio group such as an alkylthio group, e.g., ethylthio, propylthio, etc., or an arylthio group, e.g., phenylthio, tolylthio, etc.; a carboxy group; an amino group such as an N-alkylamino, cycloalkylamino, N,N-dialkylamino, N-alkyl-N-arylamino or N-arylamino group; an amido group such as an acetamido, α-(2,4-di-tert-amylphenoxy)acetamido, α-butoxyphenoxypropionamido or α-(3-pentadecyl-4-sulfonoxyacetamido)benzamido or benzamido group; an N-alkylacylamino group; an N-arylacylamino group; a ureido group such as N-arylureido or N-alkylureido group; a thioureido group such as an N-alkylthioureido or N-arylthioureido group; a carbamoyl group such as a carbamoyl; N-octadecylcarbamoyl, N,N-dihexylcarbamoyl, N-methyl-N-phenylcarbamoyl or 3-pentadecylphenylcarbamoyl group; a sulfamoyl group; a piperidino group; a pyrrolidino group; a guanidino group such as a guanidino, N-alkylguanidino or N-arylguanidino group.

R represents a group having 1 to about 30 carbon atoms, i.e., a straight chain or branched chain alkyl group such as a methyl, ethyl, i-propyl, i-amyl, 2-ethylhexyl, dodecyl or stearyl group; an alkenyl group such as an allyl or oleyl group; a cycloalkyl group such as cyclohexyl group; an alkyl or cycloalkyl group substituted with a halogen atom or a nitro, cyano, aryl, alkoxy, aryloxy, carboxyester, sulfoester, amido, sulfonamido, ureido, carbamyl or sulfamyl group, such as a 2-chloroethyl, 2-chloropropyl, 2-chlorocyclohexyl, 2-cyanoethyl, benzyl, β-phenethyl, 3-dodecyloxypropyl, 2-(2,4-di-t-amylphenoxy) ethyl, 4-(3-pentadecylphenoxy)-butyl, α-dodecyloxycarbonylethyl, 2-N,N-diethylaminoethyl, 2-acetylaminopropyl, 2-benzenesulfonamidoethyl, butyloxycarbonylmethyl, 2-acetyloxyethyl, 2-(N,N-di-n-butylamino)sulfonylethyl or 4-i-propylcyclohexyl group. Furthermore, R ₃ represents an aryl group such as a phenyl or an α- or β-naphthyl group or an aryl group substituted with one or more nitro, cyano, alkyl, aryl, alkoxy, aryloxy, alkoxycarbonyl, acyl, arylcarbonyl, alkylsulfonyl, arylsulfonyl, sulfoester, amido, sulfonamido, ureido, carbamyl and sulfamyl groups or halogen atoms. Furthermore, R ₃ represents a 5-membered or 6-membered heterocyclic group containing, as a hetero-atom, nitrogen, oxygen and/or sulfur, such as a tetrahydrofuryl, 2-furylmethyl, tetrahydrofurfuryl or 3- or 4-pyridyl group. These rings can be substituted with substituents above described for the aryl group.

R ₄ represents a divalent group (e.g., having 1 to about 30 carbon atoms) obtained by eliminating two hydroxyl groups from a divalent alcohol or divalent phenol, such as an alkylene group (e.g., ethylene, propylene, hexamethylene,, octadecamethylene, 2-butylene, 1,4-cyclohexanedimethylene, etc.), an arylene group (e.g., phenylene, methylphenylene, 2,5-di-tert-octylphenylene, chlorophenylene, methoxyphenylene, phenylphenylene, naphthylene, biphenylene, isopropylidene bisphenylene, etc.) or a xylylene group (e.g., xylylene, chloroxylylene, ethoxyxylylene, etc.).

Either of R ₁ or R ₂ may represent a divalent group of about 30 or less carbon atoms to form a bis-pyrazolone coupler.

The pyrazolone compound in which the 4-position is substituted by a carbonic ester group or an oxalic ester group, used according to the present invention, can provide various properties depending on the substituents on 1-, 3- and 4-positions and this feature is applicable to various photographic objects. When at least one of R ₁ , R ₂ , R ₃ and R ₄ contains a hydrophobic group of 8 or more carbon atoms, the coupler associates in a hydrophilic colloid and becomes non-diffusible in the hydrophilic colloid layer of a light-sensitive material. Such a coupler can be incorporated in a silver halide emulsion layer. When R ₃ or R ₄ contains a hydrophobic group of 8 or more carbon atoms and at least one of R ₁ and R ₂ contains a water-solubilizing group such as a sulfo or carboxyl group, the coupler is non-diffusible per se but can provide a diffusible dye by the oxidizing coupling reaction with an aromatic primary amine developing agent. Such a diffusible dye providing coupler is suitable for diffusion transfer color photography.

The process of forming a dye image by the oxidizing and coupling reaction with an aromatic primary amine developing agent is classified mainly into two types according to the method of adding of coupler. In one type, the so-called "internal type", the coupler is incorporated in an emulsion during the production of the light-sensitive material. A suitable amount of the pyrazolone compound of this invention which can be incorporated with emulsion layer ranges from about 2 × 10 ^-3 to 1 × 10 ^-4 mol/m ² of the support. In the other type, the so-called "external type", the coupler is dissolved in a developer and provided in the emulsion layer through diffusion during development. A suitable amount of the pyrazolone compound of this invention which can be used in the developer solution ranges from about 5 × 10 ^-2 to 5 × 10 ^-3 mol/liter of the developer solution.

The coupler used in the internal type must be fixed in an emulsion layer, that is, must be diffusion-resistant. If the coupler is not diffusion-resistant, the coupler migrates in a light-sensitive material and the color is formed in the wrong color-sensitive emulsion layer, thus markedly deteriorating the color reproduction capability of the light-sensitive material.

In order to render a coupler diffusion-resistant, a group containing a hydrophobic radical of 8 to 32 carbon atoms is introduced into the coupler molecule. This radical is generally called a "ballast group". The ballast group can be combined with the coupler skeleton directly or through an imino-, ether-, carbonamide-, sulfonamide-, ureide-, ester-, imide-, carbamoyl- or sulfamoyl-bond.

Some examples of ballast groups suitable for use in the coupler according to the invention are as follows:

I. alkyl groups and alkenyl groups e.g., ##EQU1## --C ₁₂ H ₂₅ , --C ₁₆ H ₃₃ , --C ₁₇ H ₃₃ II. Alkoxyalkyl groups e.g., --(CH ₂ ) ₃ O(CH ₂ ) ₇ CH ₃ , ##EQU2## for example, as described in Japanese Patent Publication No. 27563/1964 III. Alkylaryl groups ##SPC3##

Iv. alkylaryloxyalkyl groups ##SPC4##

V. acylamidealkyl groups ##EQU3## for example, as described in U.S. Patents 3,337,344 and 3,418,129 VI. Alkoxyaryl and Aryloxyaryl groups ##SPC5##

Vii. long chain aliphatic groups such as alkyl or alkenyl groups having a water-solubilizing group such as a carboxyl or sulfo group t,140 ,140

Viii. alkyl groups substituted with an ester group ##EQU4## -CH ₂ -CH ₂ -COOC ₁₂ H ₂₅ (n) IX. Alkyl groups substituted with an aryl group or a heterocyclic group ##SPC6##

X. aryl groups substituted with an aryloxyalkoxycarbonyl group ##SPC7##

Examples of the preferred couplers for use in the photographic light-sensitive material of this invention are given in the following. However, the invention is not to be construed to be limited to these specific examples only.

Coupler 1

1-(2-Chloro-4,6-dimethylphenyl)-3-(3-(α-(2,4-di-tert-am ylphenoxy)buty lamido)benzamido)-5-pyrazolonyl-(4)benzylcarbonic ester

Coupler 2

1-(2,4,6-Trichlorophenyl)-3-(α-(3-n-pentadecylphenoxy)b utylamido)-5-p yrazolonyl-(4)-benzylcarbonic ester

Coupler 3

1-(2,4,6-Trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphen oxy)-acetamido )benzamido)-5-pyrazolonyl-(4)-benzylcarbonic ester

Coupler 4

1-(2,4,6-Trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphen oxy)-acetamido )benzamido)-5-pyrazolonyl-(4)-ethylcarbonic ester

Coupler 5

1-(2,4,6-Trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphen oxy)-butylamid o)benzamido-5-pyrazolonyl-(4)-4-nitrobenzylcarbonic ester

Coupler 6

1-(2,6-Dichloro-4-methoxyphenyl)-3-(3-(α-(2,4-di-tert- amylphenoxy)butylamido)phenylureido)-5-pyrazolonyl-(4)-4-phe nylazobenzylca rbonic ester.

Coupler 7

1-(2,4,6-Trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphen oxy)-acetamido )benzamido)-5-pyrazolonyl-(4)-phenylcarbonic acid ester

Coupler 8

1-(2,4,6-Trichlorophenyl)-3-(2-chloro-5-(α-(2,4-di-tert -amylphenoxy)b utylamido)anilino)-5-pyrazolonyl-(4)-benzylcarbonic ester

Coupler 9

1-(2,4,6-Trichlorophenyl)-3-((2-chloro-4-n-hexadecylamid o)-anilino)-5-pyraz olonyl-(4)-cyclohexylcarbonic ester

Coupler 10

1-(2,4,6-Trichlorophenyl)-3-((2-chloro-4-n-dodecyloxycar bonyl)-anilino)-5-p yrazolonyl-(4)-4-nitrophenylcarbonic ester

Coupler 11

1-(2,4,6-Trichlorophenyl)-3-(3-(α-(b 2,4-di-tert-amylphenoxy)-acetamido)benzamido)-5-pyrazolonyl- (4)-ethyloxali c ester

Coupler 12

1-(2,4,6-Trichlorophenyl)-3-(2-chloro-5-(α-(2,4-di-tert -amylphenoxy)b utylamido)anilino)-5-pyrazolonyl-(4)-phenyloxalic ester

Coupler 13

1-(4-(α-(2,4-Di-tert-amylphenoxy)acetamido)phenyl)-3-me thyl-5-pyrazol onyl-(4)-benzylcarbonic ester

Coupler 14

1-Phenyl-3-(α-carboxymethyl-n-2-eicosanamido)-5-pyrazol onyl-(4)-ethyl carbonic ester

Coupler 15

1-(3-Potassiumsulfonato-4-phenoxyphenyl)-3-n-octadecyl-5 -pyrazolonyl-(4)-te trahydrofurylcarbonic ester

Coupler 16

1-(4-Carboxyphenyl)-3-(2-methoxy-5-carboxyanilino)-5-pyr azolonyl-(4)-octade cylcarbonic ester

Coupler 17

1-(3-Sulfo-4-phenoxyphenyl)-3-benzamido-5-pyrazolonyl-(4 )-β-(2,4-di-te rt-amylphenoxy)-ethylcarbonic ester

Coupler 18

1-(2,4,6-Trichlorophenyl)-3-(3-(α-(3-n-pentadecylphenox y)-butylamido) benzamido)-5-pyrazolonyl-(4)-ethylcarbonic ester

Coupler 19

1-(2,4,6-Trichlorophenyl)-3-((2-chloro-5-n-tetradecylami do)-anilino)-5-pyra zolonyl-(4)-ethylcarbonic ester

Coupler 20

1-(2,4,6-Trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphen oxy)acetamido) benzamido)-pyrazole-4,5-di-phenylcarbonic ester

Coupler 21

1-Phenyl-3-(3,5-dicarboxyanilino)-5-pyrazolonyl-(4)-4-(Î ±-(2,4-di-tert -amylphenoxy)butylamido)-benzylcarbonic ester

Coupler 22

1,4-bis(1-(4-(α-(2,4-Di-tert-amylphenoxy)butylamido)phe nyl)-5-pyrazol onyl-(4)-ethylcarbonic ester)-terephthalamide

Coupler 23

1-(2,4,6-Trichlorophenyl)-3-(2-chloro-5-(γ-(2,4-di-tert -amylphenoxy)p ropylsulfamoyl)anilino)-5-pyrazolonyl-(4)-benzylcarbonic ester

Coupler 24

1-(2,6-Dichloro-4-methoxyphenyl)-3-(3-(α-(3-n-pentadecy lphenoxy)aceta mido)benzamido)-5-pyrazolonyl-(4)-4-pyridylcarbonic ester

Coupler 25

α,α'-bis(1-(2,4,6-Trichlorophenyl)-3-(3-(α-(2,4-di-te rt-a mylphenoxy)acetamido)benzamido)-5-pyrazolonyl-(4))-p-xylylen edicarbonic ester

Coupler 26

1-(2,4,6-Trichlorophenyl)-3-(2-chloro-5-(α-ethoxycarbon yl-n-pentadecy loxycarbonyl)anilino)-5-pyrazolonyl-(4)-benzylcarbonic ester

Coupler 27

1-(2,4,6-Trichlorophenyl)-3-((3-(α-mthyl-β-n-octyloxy) propylamid o)benzamido)-5-pyrazolonyl-(4)-benzylcarbonic ester

Coupler 28

1-(2-Chloro-4,6-dimethylphenyl)-3-(2-chloro-4-(γ-(2,4-d i-tert-amylphe noxy)propylsulfamoyl)anilino)-5-pyrazolonyl-(4)-benzylcarbon ic ester

Coupler 29

1-(2,4,6-Trichlorophenyl)-3-((3-n-octadecylsuccinimido)b enzamido)-5-pyrazol onyl-(4)-benzylcarbonic ester

A feature of the coupler used in the invention is that one hydrogen of the active methylene group at the 4-position of the pyrazolone is substituted with a carbonic ester group or oxalic ester group. This coupler is a so-called two equivalent coupler that reacts with the oxidation product of an aromatic primary amine color developing agent to give the corresponding leucoazomethine dye and to form the pyrazoloneazomethine dye upon releasing of the carbonic monoester or oxalic monoester group. Only 4-acyloxy-5-pyrazolone compounds have hitherto been known as a 5-pyrazolone having an ester group at the 4-position of the pyrazolone. In U.S. Pat. No. 3,311,476, a synthetic example of 1-(2,4,6-trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphenoxy) acetamido)-benzamido)-4-acetoxy-5-pyrazolone is described, but the process of reaction is long and no characteristic values are described therein. When the synthetic example was carried out, the above described compound was only obtained with a low yield. We, the inventors, tried to synthesize the above described compound in another manner than that described in the U.S. Patent. When 1-(2,4,6-trichlorophenyl)-3-( 3-(α-(2,4-di-tert-amylphenoxy)acetamido)benzamido)-4-hydrox y-5-pyrazo lone was reacted with acetyl chloride in excess, it was confirmed that the corresponding 4,5-diacetoxypyrazole compound derived from the enol body of 4-hydroxy-5-pyrazolone was initially formed as an intermediate product and then converted into 4-acetoxy-5-pyrazolone through rapid and selective hydrolysis of the enol ester part at the 5-position, when allowed to stand at room temperature in the reaction solution. However, this 4-acetoxy-5-pyrazolone was so unstable that, during purification, it was hydrolyzed into 4-hydroxy-5-pyrazolone in the presence of water, rapidly oxidized and isolated as a stable pyrazole-4,5 dione body.

On the contrary, the coupler used in the invention, which has a carbonic ester group or oxalic ester group at the 4-position of the pyrazolone, can be clearly distinguished from the above described coupler in chemical structure, shows a much higher stability and the synthesis thereof is very easy as is set forth hereinafter.

The pyrazolone coupler used in the invention has the following valuable features:

The coupler of the invention is a two equivalent coupler which theoretically requires only two equivalents of silver halide, as an oxidizer, for forming one molecule of a colored dye. The required silver halide can be reduced to about half of that in using a prior art four equivalent pyrazolone type coupler, thus not only halving the silver halide contained in a light-sensitive material and reducing the production cost of the light-sensitive material, but also reducing the light scattering due to the emulsion grains and improving the sharpness of the image.

The coupler of the 4-position-substituted 5-pyrazolone type used in the invention can be converted into an azomethine dye in a high yield by the oxidizing and coupling reaction using an exposed silver halide as an oxidizer. Some of the four equivalent couplers used in the prior art have a low conversion yield into the dye, since the leuco dye as an intermediate product produces side reactions such as azine ring formation. On the contrary, the coupler of the 4-position-substituted 5-pyrazolone type used in the invention can be converted into an azomethine dye with a high yield, since reaction procession is not through such a reactive intermediate product. Consequently, in the color light-sensitive material of the invention, it is possible to reduce the quantity of the magenta-forming coupler, to reduce the content of the silver halide and to reduce the thickness of the emulsion layer. Thus, it is easy to reduce the cost of the light-sensitive material, to improve the sharpness and to promote the development.

The coupler of the 4-position-substituted 5-pyrazolone type used in the invention has generally a strong coupling activity for an oxidized aromatic primary amine color developing agent and rapidly removes the oxidized product of the developing agent formed during color development, so that the development of a silver halide emulsion is accelerated.

In the coupler of the 4-position-substituted 5-pyrazolone used in the invention, the process of forming a dye is completed in a color developing bath and it is not necessary to use thereafter a bleaching bath containing a strong oxidizer such as potassium ferricyanide or potassium bichromate. Thus a treatment with a bleaching and fixing bath containing a silver complex salt forming agent and weak oxidizer such as a ferric chelate of EDTA or a bleaching bath containing a mercuric salt such as mercuric chloride is possible and, consequently, it is easy to shorten the time for all the processings of color development as well as to solve the problem of environmental pollution in processing solution discharge.

On the contrary, in some four equivalent couplers in which the position of the coupling reaction is not substituted, the color forming reaction is not completed in a color developing bath and a considerable portion of the coupling reaction product remains in the colorless leuco form, which requires an additional treatment with an oxidizer as described above for complete color formation.

The 4-position-substituted 5-pyrazolone coupler used in the invention is inactivated by carbonyl compounds such as aldehydes and ketones to a less extent, while the 4-position-non-substituted 5-pyrazolone coupler used in the prior art, in particular, in an emulsion layer is changed into a compound of low color forming reactivity such as a methylol or methylene-bis compound by formaldehyde in the air, which often does not provide sufficient color forming property during color development. Such a change in the coupler markedly reduces the color reproduction of a color light-sensitive material. One feature of the color light-sensitive material of the invention is that the material is hardly influenced by such chemicals.

The 4-position-substituted 5-pyrazolone of the invention has the advantages, when used for conventional color light-sensitive materials as described in the Examples, that the stability during the passage of time is high in an emulsion film and, in particular, the color forming property is reduced to a lesser extent even after the passage of time at low temperature under high humidity, as compared with the above described known couplers. In a color light-sensitive material, the stability of the duration of a fresh film is one of the most important factors as to the assessment of the characters thereof. Moreover, it is found that a color developed image from the 4-position-substituted coupler of the invention has more excellent heat resistance than that from 4-position-non-substituted couplers and, even in comparison with the foregoing known coupler having a 4-position substituent on the same pyrazolone nucleus, the coupler of the invention has a higher heat resistance.

The coupler of the invention in which the 4-position is substituted by a carbonic ester group or an oxalic ester group, as represented by the foregoing General Formula (I) or (II), can readily be obtained by reaction of a 4-hydroxy-5-pyrazolone represented by General Formula (III), ##SPC8##

and an acid chloride represented by General Formula (IV),

in which R ₁ , R ₂ , R ₃ , R ₄ and n have the same meanings as in General Formula (I) or (II).

The 4-hydroxy-5-pyrazolones represented by General Formula (III) can be obtained with a high yield by reducing the corresponding pyrazolone-4,5-dione compound in conventional manner (for example, a catalytic hydrogenation using a metallic catalyst such as palladium-carbon or a reduction using zincacetic acid or sodium borohydride), e.g., as described in U.S. Pat. No. 3,419,391. The pyrazolone-4,5-dione compound can be obtained by converting the 5-pyrazolone into the corresponding azomethine dye, followed by hydrolysis with sulfuric acid, as described in U.S. Pat. No. 3,311,476, or by converting the 5-pyrazolone into the 4-amino-5-pyrazolone, followed by oxidation of the amino group, as disclosed in U.S. Pat. No. 3,419,391.

The synthesis methods of the acid chlorides represented by General Formula (IV) are well known and some of the acid chlorides are easily obtainable.

Sysnthetic Examples of the coupler of the invention are given in the following. Unless otherwise indicated herein, all parts, percents, ratios and the like are by weight.

SYNTHETIC EXAMPLE 1

Preparation of 1-(2,4,6-Trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphenoxy) acetamido o)benzamido)-5-pyrazolonyl-(4)-benzylcarbonic ester (Coupler 3)

32.4g of 1-(2,4,6-trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphenoxy) acetamido )benzamido)-4-hydroxy-5-pyrazolone was dissolved in 1000ml of anhydrous diethyl ether under a nitrogen atmosphere, mixed with 17.0g of chlorocarbonic benzyl ester, stirred at 20°C for 5 minutes and then mixed with 11.2g of triethylamine. After reaction at the same temperature for 10 minutes, the precipitated triethylamine hydrochloride was filtered and 6.0g of triethylamine was further added to the filtrate. The precipitated solid was removed by filtration, washed adequately with diethyl ether and dissolved in 100ml of acetic acid. This solutioon was poured in 1200ml of ice water, the precipitated white solid was removed by filtration and dried. This is an extremely pure Coupler 3 that does not require a further purification. Yield: 33.8g; M.P.: 109°-110°C

Ir spectrum (Nujol): νC=0

1760cm ^-1 , νC--O--C, 1240cm ^-1 , 1230cm ^-1

Nmr spectrum: δCDCl ₃

525 ppm (2H), 6.68 - 8.10 ppm (14H)

Elemental Analysis:

Found: C 61.10; H 5.24; N 7.02%. Calculated: C 61.40; H 5.24; N 6.82%.

SYNTHETIC EXAMPLE 2

Preparation of 1-(2,4,6-Trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphenoxy) acetamido )benzamido)-5-pyrazolonyl-(4)-ethyl carbonic ester (Coupler 4)

This coupler was obtained in a manner analogous to Coupler 3. That is, 46.2g of 1-(2,4,6-trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphenoxy) -acetamid o)benzamido)-4-hydroxy-5-pyrazolone was dissolved in 1200ml of anhydrous diethyl ether, to which 15.2g of chlorocarbonic ethyl ester and 16.1g of triethylamine were added, and the mixture was reacted. After the reaction, the precipitated triethylamine hydrochloride was filtered, 7.3g of triethylamine was added to the filtrate and the precipitated solid was remooved by filtration. This was dissolved in 120ml of acetic acid, poured in 1800ml of ice water and the precipitated solid was removed by filtration followed by drying. Yield:42.3g; M.P.: 115°- 121°C

Ir spectrum (Nujol): νC=0

1760cm ^-1 , νC--O--C, 1250cm ^-1 (broad)

Nmr spectrum: δCDCl ₃

4.30ppm (2H, q, 8H _z ), 8.45 ppm (9H)

Elemental Analysis:

Found: C 58.22; H 5.43; N 7.14. Calculated: C 58.50; H 5.40; N 7.38.

SYNTHETIC EXAMPLE 3

Preparation of 1-(2,4,6-Trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphenoxy) acetamido )benzamido)-5-pyrazolonyl-(4)-phenyl carbonic ester (Coupler 7)

This coupler was synthesized in a manner analogous to Coupler 3. That is, 43.8g of 1-(2,4,6-trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphenoxy) -acetamid o)benzamido)-4-hydroxy-5-pyrazolone was dissolved in 1000ml of anhydrous diethyl ether, to which 20.9g of chlorocarbonic phenyl ester and 14.3g of triethylamine were then added, and the mixture was reacted. After the reaction, the precipitated triethylamine hydrochloride was filtered, 7.2g of triethylamine was added to the filtrate followed by stirring for one night and the precipitated solid was removed by filtration. This is dissolved in 120ml of acetic acid, poured in 2000ml of ice water and the precipitated solid was removed by filtration followed by drying. Yield: 35.2g; M.P. 110° - 113°C

Ir spectrum (Nujol): νC=0

1755cm ^-1 , νC--O--C, 1240cm ^-1 (broad)

Nmr spectrum: κCDCl ₃

6.52 - 8.30 ppm (14H)

When the filtrate was allowed to stand at 20°C for one day and night, 5.8g of colorless crystals was obtained, corresponding to 1-(2,4,6-trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphenoxy) acetamido)benzamido)-pyrazole-4,5-di-phenyl carbonic acid ester (Coupler 20) having a M.P. of 126° - 130°C.

Nmr spectrum: δCDCl ₃

6.48 - 8.29ppm (19H)

Elemental Analysis:

Found: C 60.82; H 5.11; N 7.11. Calculated: C 61.00; H 5.08; N 6.95.

SYNTHETIC EXAMPLE 4

Preparatioon of 1-(2,4,6-Trichlorophenyl)-3-(2-chloro-5-(α-(2,4-di-tert-amy lphenoxy) butylamido)anilino)-5-pyrazolonyl-(4)-benzylcarbonic ester (Coupler 8)

This coupler was synthesized in a manner analogous to Coupler 3. 24.2g of 1-(2,4,6-trichlorophenyl)-3-(2-chloro-5-(α-(2,4-di-tert-amy lphenoxy) -butylamido)anilino)-4-hydroxy-5-pyrazolone was dissolved in 800ml of anhydrous diethyl ether, to which 12.4g of chlorocarbonic benzyl ester and 7.5g of triethylamine were added, and the mixture was reacted. The precipitated triethylamine hydrochloride was filtered and 4.0g of triethylamine was added to the filtrate. The precipitated solid was removed by filtration, dissolved in 60ml of acetic acid, poured in 700ml of ice water and then the precipitated solid was removed by filtration, followed by drying. Yield: 20.4g; M.P.: 118° - 119°C

Ir spectrum (Nujol): νC=0

1761cm ^-1 , νC--OO--C, 1241, 1230cm ^-1

Nmr spectrum: δCOCl ₃

5.12ppm (2H), 6.47 - 8.15ppm (13H)

Elemental Analysis:

Found: C 60.32; H 5.46; N 6.68. Calculated: C 60.50; H 5.40; N 6.57.

SYNTHETIC EXAMPLE 5

Preparation of 1-(2,4,6-Trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphenoxy) acetamido )benzamido)-5-pyrazolonyl-(4)-ethyl oxalic ester (Coupler 11)

27.3g of 1-(2,4,6-trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphenoxy) acetamido )benzamido)-4-hydroxy-5-pyrazolone was dissolved in 1000ml of anhydrous diethyl ether, mixed with 11.8g of chlorooxalic acid ethyl ester and stirred at 20°C for several minutes. Then 6.9g of pyridine was added dropwise to the mixture, reacted for 10 minutes and the precipitated oily substance was removed. This was dissolved in 60ml of acetic acid, poured in 1000ml of ice water and the precipitated solid was removed by filtration. After drying, the solid was dissolved in diethyl ether, mixed with 4.2g of triethylamine and the precipitated solid was removed by filtration. After washing adequately with diethyl ether, the solid was dissolved in 50ml of acetic acid again, poured in 800ml of ice water and the precipitated solid was removed by filtration, followed by drying. Yield: 19.8g; M.P.: 126° - 128°C

Ir spectrum (Nujol): νC=0

176.2cm ^-1 , 1748cm ^-1 , νC--O--C, 1240cm ^-1 (broad) NMR Spectrum: δCOCl ₃

4.53ppm (2H, q, 7cps),6.62 - 8.28ppm (9H)

Elemental Analysis:

Found: C 58.40; H 5.36; N 7.32. Calculated: C 58.10; H 5.22; N 7.13.

The term aromatic primary amine developing agent as used in the invention means a compound which has a primary amino group on an aromatic ring and is capable of developing exposed silver halide, or a precursor which is capable of forming such a compound. In particular, N,N-p-phenylenediamines are suitable for the practice of the invention. Other examples of such amines are 4-amino-3-methyl-N-ethyl-N-(methoxyethyl)aniline, 4-amino-3-methyl-N-ethyl-N-(ethoxyethyl)aniline, 4-amino-3-ethoxy-N,N-diethylaniline, 4-amino-3,5-dimethyl-N,N-diethyl aniline, 4-amino-3-methyl-N-ethyl-N-(β-hydroxyethyl)aniline, 4-amino-3-methyl-N,N-diethylaniline, 4-amino-3-methyl-N-ethyl-N-(β-methanesulfonamidoethyl)anili ne, 4-amino-3-(β-methanesulfonamidoethyl)-N,N-diethylaniline, 4-amino-N-ethyl-N-(β-hydroxyethyl)aniline, 4-amino-N,N-diethylaniline and 4-amino-N-ethyl-N-ω-sulfobutylaniline. The photographic material of the invention is developed with a solution containing the above described aromatic primary amine developing agents, an alkali agent, and optionally, a preservative, antifoggant and a sensitizer, after exposure. Suitable examples of such addenda are disclosed in C.E.K.Mees and T.H.James, The Theory of the Photographic Process, and U.S. Pat. Nos. 2,592,364; 2,193,015; etc.

The silver halide emulsion of the invention comprises a silver halide such as silver chloride, silver bromide, silver iodide, or a mixed silver halide such as silver chlorobromide, silver iodobromide or silver chloroiodobromide, dispersed in a hydrophilic high molecule material such as gelatin. The grain size can range from a uniform grain size to a grain size having a broad grain size distribution. Depending upon the end-use objects of the light-sensitive material, an emulsion is suitably selected having an average grain size within a range of from about 0.05 to about 3 microns. The silver halide emulsion can be prepared, for example, using a mixing method such as single or double jet methods or using an ripening method such as ammonia, neutral or acidic methods. Moreover, the silver halide emulsion can be subjected to a sensitizing treatment such as sulfur sensitization, gold sensitization or reduction sensitization using conventional techniques. Suitable examples of chemical sensitizers are auric compounds such as auric chloride compounds as disclosed in U.S. Pat. Nos. 2,399,083; 2,540,085; 2,597,856; 2,597,915; etc.; the noble metal salts of platinum, palladium, iridium, rhodium, or ruthenium as disclosed in U.S. Pat. Nos. 2,448,060; 2,540,086; 2,566,245; 2,566,263; 2,598,079; etc.; sulfur compounds which react with silver salts to form silver sulfide as disclosed in U.S. Pat. Nos. 1,574,944; 2,410,689; 3,189,458; 3,501,313; etc.; reduction compounds of stannous salts or amine group containing compounds as disclosed in U.S. Pat. Nos. 2,487,850; 2,518,698; 2,521,925; 2,521,926; 2,694;637; 2,983,610; 3,201,254; etc. The emulsion can also contain a sensitizer such as polyoxyethylene compounds and onium compounds. Not only emulsions of the type that a latent image is mainly formed on the surface, but also those of the internal latent image type that a latent image is mainly formed inside the grains can be used in the present invention, for example, as disclosed in C. E. K. Mees and T. H. James, The Theory of the Photographic Process.

Suitable hydrophilic high molecular weight materials for forming the light-sensitive layer of the invention are proteins such as gelatin, high molecular weight non-electrolytes such as polyvinyl alcohol, polyvinylpyrrolidone and polyacrylamide, acidic high molecular weight materials such as alginates and polyacrylates and high molecular weight amphoteric electrolytes such as polyacrylamide treated by the Hofmann rearrangement reaction and acrylic acid-N-vinylimidazole copolymers. The hydrophilic high molecular material forming a continuous phase can contain a dispersed hydrophobic high molecular weight material, for example, a latex of polyacrylic acid butyl ester.

The silver halide photographic emulsion of the invention is suitably applied to a support. As the support, hard materials such as glass, metals and ceramics, and flexible materials can be used depending on the end-use objects. Typical flexible supports are cellulose nitrate films, cellulose acetate films, polyvinyl acetal films, polystyrene films, polyethylene terephthalate films, polycarbonate films and their laminates, papers coated with baryta and α-olefin polymers such as polyethylene, polypropylene and ethylene-butene polymers, and plastic films having a roughened surface as disclosed in Japanese Patent Publication No. 19068/1972. Depending upon the end-use objects of the light-sensitive material, the support can be transparent, colored by adding a dye or pigment, opaque by adding, for example, titanium white or blackened by adding, for example, carbon black.

Formation of a color image according to the invention can be achieved in light-sensitive materials of various forms. In one form, a light-sensitive material having a silver halide emulsion layer containing a diffusion resistant coupler on a support is treated with an alkaline developer containing an aromatic primary amine color developing agent to retain a water-insoluble or diffusion resistant dye in the emulsion layer. Examples of such systems are disclosed in U.S. Pat. Nos. 3,419,391; 2,304,939; 2,322,027; 2,949,360; 2,801,171; 2,801,170; 3,311,476; 3,271,152; 3,519,429; etc. In another form, a light-sensitive material having a silver halide emulsion layer in combination with a diffusion resistant coupler on a support is treated with an alkaline developer containing an aromatic primary amine color developing agent to form a dye soluble in an aqueous medium and diffusible and then transferred to another receiving layer of a hydrophilic colloid. This is a diffusion and transfer color system. Examples of such systems are disclosed in U.S. Pat. Nos. 3,342,597; 3,227,551; 3,227,550; 3,227,554; 3,644,498; 3,476,563; 3,353,672; 3,330,655; etc.

Couplers 16, 17 and 21 can be used for the second form described above, while the others can be used for the first form described.

The 5-pyrazolone coupler of the invention, in which the 4-position is substituted with a carbonic ester or oxalic ester group and which has a hydrophobic radical of 8 or more carbon atoms, is dissolved in an aqueous medium or organic solvent and then dispersed in a photographic emulsion.

The oil-soluble and diffusion-resistant coupler used in the internal type is incorporated in a light-sensitive material by dissolving the coupler in an organic solvent and then dispersing the solution in a photographic emulsion as fine colloidal grains.

A coupler dispersing method suitable for the practice of the invention is illustrated in detail, for example, in U.S. Pat. No. 3,676,137. Organic solvents capable of dissolving the coupler, hardly soluble in water, having a high boiling point (e.g., above 170°C) and present with the coupler in a color light-sensitive material are selected from substituted hydrocarbons, carboxylic acid amides, phosphoric acid esters and ethers, for example, di-n-butyl phthalate, di-i-octyl acetate, di-n-butyl sebacate, tricresyl phosphate, tri-n-hexyl phosphate, N,N-diethylcaprylamide, butyl-n-pentadecylphenyl ether and chlorinated paraffins. In addition to these high boiling point solvents, auxiliary solvents for dissolving the coupler, which can be removed during the production of a light-sensitive material, are preferably used, for example, ethyl acetate, butyl acetate, cyclohexanol, tetrahydrofuran and cyclohexanone.

Surfactants are preferably used as an aid to disperse the oil-soluble coupler of the internal type finely in a hydrophilic high molecular material used in the photographic emulsion. Illustrative of such surfactants are anionic surfactants such as sodium cetylsulfate, sodium p-dodecylbenzenesulfonate, sodium nonylnaphthalenesulfonate and sodium di(2-ethylhexyl)-α-sulfosuccinate, and nonionic surfactants such as sorbitan sesquioleic acid esters and sorbitan monolauric acid esters.

For the dispersion of an oil-soluble coupler, an emulsifying homogenizer, colloid mill and ultrasonic wave emulsifying apparatus are suitable. A diffusion resistant coupler having a ballast group and carboxylic acid group or sulfonic acid group in the same molecule is soluble in a neutral or weakly alkaline aqueous solution. The coupler can be incorporated in a photographic emulsion by adding an aqueous solution containing the coupler to the photographic emulsion. The coupler is believed to be diffusion resistant through the formation of micelles in the hydrophilic high molecular material.

The two equivalent coupler of the invention can be used together with one or more of the magenta couplers as described in U.S. Pat. Nos. 2,439,098; 2,369,489; 2,600,788; 3,558,319; 2,311,081; 3,419,391, 3,006,759; 2,725,292; 2,908,573; 3,519,429; 3,152,896; 3,062,653 and 3,311,476, British Pat. No. 956,261, Japanese Pat. Publication No. 19032/1971, Japanese Pat. Application Nos. 114445/1972 and 114446/1972, the magenta colored couplers described in U.S. Pat. Nos. 2,983,608; 2,455,170; 2,725,292; 3,005,712; 3,519,429; and 2,688,539, British Pat. Nos. 800,262 and 1,044,778 and Belgian Pat. No. 676,691, the so-called DIR type couplers capable of releasing a compound imagewise suppressing development during development, for example, the monothio type couplers described in U.S. Pat. No. 3,227,554 and British Pat. No. 953,454, the o-aminophenyl azo type couplers described in U.S. Pat. No. 3,148,062, the 4-halogenated pyrazolone type couplers described in U.S. Pat. No. 3,006,759 and the couplers described in Japanese Patent Publication No. 8750/1972 and German OLS No. 2,163,811, and the hydroquinones capable of releasing a compound suppressing development during developing, as described in U.S. Pat. No. 3,297,445 and British Pat. No. 1,058,606.

In order to increase the stability of the color photograph, it is desirable that the light-sensitive material of the invention contain a p-substituted phenol derivative in the emulsion layer or in an adjacent layer thereof. Particularly suitable p-substituted phenol derivatives can be selected from one or more of the hydroquinone derivatives described in U.S. Pat. Nos. 2,360,290; 2,418,613; 2,675,314; 2,701,197; 2,704,713; 2,710.801; 2,728,659; 2,732,300; 2,735,765 and 2,816,028, the gallic acid derivatives described in U.S. Pat. Nos. 3,457,079 and 3,069,262 and Japanese Pat. Publication No. 13496/1968, the p-alkoxyphenols described in U.S. Pat. No. 2,735,765 and 3,698,909, and the p-oxyphenols described in U.S. Pat. Nos. 3,432,300; 3,573,050; 3,574,627 and 3,764,337.

For the purpose of image stability, the light-sensitive material of the invention can preferably contain an ultraviolet absorbent in the emulsion layer or in an adjacent layer, as described in U.S. Pat. Nos. 3,250,617 and 3,253,921.

The hydrophilic colloid layer in the light-sensitive material of the invention, in particular, the gelatin layer can be hardened employing conventional techniques using various cross-linking agents. Examples of such hardeners are aldehyde group compounds such as formaldehyde, glutaraldehyde, ketone compounds such as diacetyl, cyclopentandione, etc.; reactive halogen containing compounds such as bis-(2-chloroethylurea), 2-hydroxy-4,6-dichloro-1,3,5-triazine, as disclosed in U.S. Pat. Nos. 3,288,775 and 2,732,303, British Pat. Nos. 974,723 and 1,167,207, etc.; active vinyl group containing compounds such as divinylsulfone, 5-acetyl-1,3-diacryloylhexahydro-1,3,5-triazine, as disclosed in U.S. Pat. Nos. 3,635,718 and 3,232,763, British Pat. No. 994,869, etc.; N-methylol compounds such as N-hydroxymethylphthalimide as disclosed in U.S. Pat. Nos. 2,732,316 and 2,586,168, etc.; isocyanate group containing compounds such as those disclosed in U.S. Pat. Nos. 3,017,280; 2,983,611, etc.; organic sulfuric or carboxylic acid derivatives such as those disclosed in U.S. Pat. No. 3,100,704; epoxy compounds such as those disclosed in U.S. Pat. No. 3,091,537; isooxazole group containing compounds such as those disclosed in U.S. Pat. Nos. 3,321,313 and 3,543,292; halocarboxyaldehyde group containing compounds such as mucochloric acid, dioxane derivatives such as dihydroxydioxane, dichlorodioxane; or inorganic hardeners such as chrom alum, zirconium sulfate, etc.

In addition, the alkali metal bisulfite aldehyde adducts, the methylol derivatives of hydantoin, and a primary fatty acid group nitro alcohol can be used as a hardening agent. Non-aldehyde type cross-linking agents such as those compounds having a plurality of epoxy rings as described in Japanese Pat. Publication 7133/1959, the poly-(1-aziridinyl) compounds described in Japanese Pat. Publication 8790/1962 and the active halogen compounds described in U.S. Pat. Nos. 3,362,827 and 3,325,287 are particularly suitable for use in the light-sensitive material of the invention.

The following examples are given in order to illustrate the invention in greater detail.

EXAMPLE 1

A mixture of 23g of 1-(2,4,6-trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphenoxy) acetamido )benzamido)-5-pyrazolonyl-(4)-benzyl carbonic acid ester (Coupler 3), 20 ml of tricresyl phosphate and 40ml of ethyl acetate was heated at 60°C to prepare a solution and the resulting solution was added to 250ml of an aqueous solution containing 25g of gelatin and 0.75g of sodium dodecylbenzenesulfonate at 60°C, followed by vigorous mechanical stirring, thus obtaining an emulsified coupler dispersion. The resulting coupler emulsion was mixed with 200g of a photographic emulsion containing 11.2 × 10 ^{- 2} mol of silver chlorobromide (silver bromide 45 mol%, silver chloride 55 mol%) and 20g of gelatin and, after 10ml of a 3% acetone solution of triethylenephosphamide as a hardener was added thereto and the final pH was adjusted to 6.5, the mixture was coated onto a cellulose triacetate film base to give a film thickness of 4.3 microns on dry basis (Film A). This film contained, per 1m ² , 1.55 × 10 ^{- 3} mol of the coupler and 6.2 × 10 ^{- 3} mol of silver chlorobromide.

For comparison, 18.9g of 1-(2,4,6-trichlorophenyl)-3-(3-(α-(2,4-di-tert-amylphenoxy) acetamido )benzamido)-5-pyrazolone (Coupler (a)) as a corresponding comparison coupler in which the coupling position was not substituted was dispersed, in place of the above described coupler, in a manner analogous to the above described coupler, mixed with 400g of the same emulsion as described above and coated onto a film to give a film thickness of 5.1 microns on dry basis (Film B). This film contained, per 1m ² , 1.57 × 10 ^{- 1} mol of the coupler and 12.6 × 10 ^{- 3} mol of silver chlorobromide.

These films were subjected to stepwise exposure and then to the following development processings:

I) Color Development 1. Color Development 21°C 12 min 2. Water Washing " 30 sec 3. First Fixing " 4 min 4. Water Washing " 4 " 5. Bleaching " 8 " 6. Water Washing " 4 " 7. Second Fixing " 4 " 8. Water Washing " 6 " II) Liquid Composition of Color Development Sodium Hexametaphosphate 2 g Sodium Sulfite (anhydrous) 2 g Benzyl Alcohol 5 ml Sodium Carbonate (monohydrate) 27.5g Potassium Bromide 0.5g Hydroxylammonium Sulfate 2.5g 4-Amino-3-methyl-N-ethyl-N-(β-methane- sulfonamidoethyl)aniline Sesquisulfate 2.5g III) Fixing Solution Sodium Thiosulfate (hexahydrate) 80 g Sodium Sulfite (anhydrous) 5 g Borax 6 g Glacial Acetic Acid 4 ml Potassium Alum 7 g Water to 1000 ml (ph = 4.5) IV) Bleaching Bath Potassium Ferricyanide 100 g Potassium Bromide 5 g Boric Acid 10 g Borax 5 g Water to 1000 ml (ph = 7.2)

After the processings, these films were subjected to measurement of the optical density with green light to thus obtain the photographic properties as shown in the following table. A sharp color image was obtained having an absorption maximum of 548mμ.

TABLE 1 ____________________________________________________________ ______________ Photographic Property ____________________________________________________________ ______________ AgX/ Rela- Coating Amount Coupler Film tive* Maximum Cou- (mol/m ² ) (Molar Thick- Sensi- Color Film pler Coupler AgX Ratio) ness Fog Gamma tivity Density ____________________________________________________________ ______________ A 3 1.55× 6.2× 4 4.3 0.03 3.09 100 3.61 10 ^{- 3} 10 ^{- 3} B a 1.57× 12.6× 8 5.1 0.02 2.25 96 2.48 10 ^{- 3} 10 ^{- 3} ____________________________________________________________ ______________ *Relative sensitivity means the quantity of exposure necessary for giving a density of fog + 0.1.

TABLE 2 ______________________________________ Developing Time for Maximum Color Density Film 4 min 8 min 12 min 16 min ______________________________________ A 3.52 3.59 3.61 3.61 B 2.36 2.45 2.48 2.51 ______________________________________

After the stepwise exposure, Film A and Film B were subjected to the above described processings 1 to 4 and dried, and the quantity of developed silver per unit area was measured by fluorescent X ray. Then the films were subjected to the above described processings 5 to 8 to obtain magenta color images. From these films, the dyes were extracted with a mixture of dimethylformamide and water in a ratio of 85:15 by volume and subjected to quantitative measurement using an absorbancy method. When calculating the molar ratios of developed silver/colored dye at various density stages, Film A gave 2.8 - 3.4 and Film B gave 8 - 8.5 as shown in the accompanying drawing.

It can be clearly understood from these results that the coupler of the invention, i.e., the two equivalent coupler having a carbonic acid ester group at the 4-position, is superior to the four equivalent coupler having the corresponding skeleton as to various properties.

As is evident from the results in Table 1, the coupler of the invention provided a higher sensitivity and gradation as well as a maximum developed density, even when the ratio of silver halide/coupler decreases to about 1/2, and as is evident from the results in Table 2, the use of the coupler of the invention results in shortening markedly the developing time. Moreover, it is shown in the accompanying drawing that in using the coupler of the invention, the quantity of developed silver necessary for obtaining a color image having a certain density can be reduced to a greater extent. These results show that the quantities of the coupler and coated silver halide necessary for obtaining a certain maximum developed density can be reduced and the developing time can be shortened.

EXAMPLE 2

Using Film A and Film B as shown in Example 1, the following processings were carried out:

V) Color Development 1. Color Development 30°C 4 min 2. Bleaching and Fixing " 2 min 3. Water Washing 2 min 4. Stabilizing Bath 2 min

The photographic properties of the thus obtained films are shown in Table 3.

As to Processing No. 4, the Stabilizing Bath, two kinds of stabilizing baths, i.e., Stabilizing Bath (a) containing no formaldehyde and Stabilizing Bath (b) containing 1% of 40% formaldehyde were prepared. The films were treated respectively with these baths, allowed to stand at 80°C for one week and the decreasing ratio of the density was measured based on the initial density and the results are tabulated in Table 4. ##EQU5##

TABLE 3 ______________________________________ Photographic Property (Stabilizing Bath (a)) Film Coupler Fog Gamma Maximum Developed Density ______________________________________ A 3 0.04 3.12 3.65 B a 0.03 2.30 2.45 ______________________________________

TABLE 4 ______________________________________ Durability of Developed Color Image (80°C, Standing for One Week) Initial Density Film Stabilizing Bath 0.5 1.0 2.0 ______________________________________ A a 15 % 10 % 7 % b 12 8 7 B a 70 53 15 b 13 9 8 ______________________________________ The results of Table 3 show that the use of Film A results in a sufficient photographic property even though a strong oxidizer is not used as in the development of Example 1 and Film A has more excellent properties than Film B. The results of Table 4 show that Film A gives a sufficient heat durability even though not subjected to a stabilizing bath treatment containing formaldehyde as in the prior art.

EXAMPLE 3

A mixture of 10g of 1-(2,4,6-trichlorophenyl)-3-(3-(α-(3-n-pentadecylphenoxy)bu tylamido) benzamido)-5-pyrazolonyl-(4)-ethyl carbonic acid ester (Coupler 18), 0.8g of 2,5-di-tert-octylhydroquinone, 0.8g of 6,6'-dihydrox-7,7'-dimethyl-4,4,4',4'-tetramethyl-bis-2,2'-s pirochroman, 10ml of dioctyl butyl phosphate and 30ml of ethyl acetate was heated and dissolved on a steam bath and added to an aqueous solution containing 10g of gelatin and 0.5g of sodium cetylsulfate, followed by vigorous mechanical stirring, thus obtaining an emulsified coupler dispersion. This emulsion was mixed with 100g of a photographic emulsion containing 4.7 × 10 ^-2 mol of silver chlorobromide (silver chloride 50 mol%, silver bromide 50 mol%) and 9g of gelatin, to which 3ml of a 4% aqueous solution of 2-hydroxy-4,6-dichloro-s-triazine sodium salt as a hardener was then added, and the pH was adjusted to 6.3. The resultant mixture was coated onto a baryta paper resin-coated with polyethylene to give a coating thickness of 1.6 microns on dry basis (Film C). In this film, 5.2 × 10 ^-4 mol of the coupler and 2.08 × 10 ^-3 mol of the silver halide were coated per 1m ² .

For comparison, another emulsified dispersion was prepared in the same manner as above but using 9.0g of a 4-position non-substituted corresponding comparison coupler, i.e., 1-(2,4,6-trichlorophenyl)-3-(3-(α-(3-n-pentadecylphenoxy)bu tylamido) benzamido)-5-pyrazolone (Coupler b), in place of the coupler of Film C, mixed with 200g of the emulsion having the same composition and coated to give a coating thickness of 2.8 microns on dry basis (Film D). In this film, 7.6 × 10 ^-4 mol of the coupler and 6.08 × 10 ¹¹⁶ 3 mol of the silver halide were coated per 1m ² .

When these samples were subjected to development (Stabilizing Bath a) similar to Example 2 and the reflection density was measured with green light, the photographic properties as shown in Table 5 were obtained. A sharp color image of a main wavelength of 541mμ was obtained.

TABLE 5 ____________________________________________________________ ______________ Photographic Property ____________________________________________________________ ______________ AgX/ Rela- Coating Amount Coupler tive Maximum Cou- (mol/m ² ) (Molar Sensi- Developed Film pler Coupler AgX Ratio) Fog Gamma tivity Density ____________________________________________________________ ______________ C 18 5.2× 2.08× 4 0.07 2.53 100 2.35 10 ^{- 4} 10 ^{- 3} D b 7.6× 6.08× 8 0.05 2.59 98 2.40 10 ^{- 4} 10 ^{- 3} ____________________________________________________________ ______________

It is apparent from the results in Table 5 that the light-sensitive material using the coupler of the invention provides similar photographic properties to those of the prior art even though the coating amounts of the coupler and silver halide are decreased.

In Table 6, the light durability when the thus obtained developed films were exposed to a sunlight fluorescent lamp of 10,000 luxes through a filter capable of absorbing substantially all ultraviolet rays having a wavelength of 400mμ or less for 12 days, the heat durability when these films were allowed to stand at 80°C in the dark for one week and the humidity durability when these films were stored in the dark at 60°C and 75% RH (Relative Humidity) for 2 weeks are shown by the decreasing ratio of density (%) based on the initial density.

TABLE 6 ____________________________________________________________ ______________ Durability of Color Image ____________________________________________________________ ______________ (Density Decreasing Ratio %) Fluorescent Lamp 60°C, 75% RH 12 Days 80°C, 1 Week 2 Weeks Initial Density Initial Density Initial Density Film Coupler 0.5 1.0 2.0 0.5 1.0 2.0 0.5 1.0 2.0 ____________________________________________________________ ______________ C 18 17 14 8 12 8 6 5 3 0 D b 25 21 14 64 54 18 7 5 2 ____________________________________________________________ ______________

It is apparent from these results that in using the coupler of the invention, an image can be obtained which is more durable to heat, light, high temperature and high humidity as compared with using four equivalent couplers having a skeleton corresponding to the coupler of the invention.

EXAMPLE 4

Onto a baryta paper resin-coated with polyethylene were coated, as a first layer, a blue-sensitive silver chlorobromide emulsion containing α-pivaloyl-α-(2,4-dioxo-5,5-dimethyloxazolidinyl)-2-chloro -5-( α-(2,4-di-tert-amylphenoxy)butylamido) acetanilide in a thickness of 3.0 microns (silver coated amount: 3.53 × 10 ^-3 mol/m ² ; coupler coated amount: 1.2 × 10 ^-3 mol/m ² ) and further, as a second layer, a gelatin containing 2-t-octylhydroquinone in a thickness of 1.5 microns. Furthermore, an emulsified dispersion of a coupler was prepared in the same manner but using 8.25g of the Coupler 19 of the invention, i.e., 1-(2,4,6-trichloro)-phenyl-3-((2-chloro-5-n-tetradecanamido) anilino)-5-pyrazolonyl-(4)-ethyl carbonic ester in place of Coupler 18 of Example 3, and using tricresyl phosphate in place of the dioctyl butyl phosphate, added to a green sensitive photographic emulsion having the same composition as in Example 3 and coated in a coating thickness of 1.7 microns as a third layer (silver coated amount: 2.08 × 10 ^-3 mol/m ² ; coupler coated amount: 5.2 × 10 ^-4 mol/m ² ), a gelatin containing 2,5-di-t-octylhydroquinone and, as an ultraviolet absorbent, 2-(5-chlorobenzotriazol-2-yl)-4-methyl-6-t-butylphenol and 2-(benzotriazol-2-yl)-4-t-butylphenol was coated in a coating thickness of 2.5 microns as a fourth layer, a red-sensitive emulsion containing 2-(α-(2,4-di-t-amyl-phenoxy)butylamide)-4,6-dichloro-5-meth yl-phenol was coated in a coating thickness of 2.5 microns as a fifth layer (silver coated amount: 2.94 × 10 ^-3 mol/m ² ; coupler coated amount:1.1 × 10 ^-3 mol/m ² ) and gelatin was then coated in a thickness of 1.0 micron as an uppermost layer, thus obtaining a color print paper.

This color print paper was exposed through a color negative and developed in a manner analogous to Example 2. The resulting color print was a sharp color photographic image very excellent in color reduction and containing a magenta color image having an absorption maximum at 541μ.

When this color print was exposed to the sunlight directly for one week, the reduction of density of the magenta color image having an initial reflection density of 1.0 was only 0.08 and, even though it was allowed to stand under high temperature and high humidity conditions, for example, at 60°C and 75% RH for 2 weeks, no substantial reduction of the density was found. In any case, it was noted that the non-image area was scarcely yellowed.

EXAMPLE 5

1.4 × 10 ^-2 mol of each of the various couplers of the invention was mixed with 10ml of tricresyl phosphate and 30ml of ethyl acetate, heated to dissolve and added to 100ml of an aqueous solution containing 10g of gelatin and 0.5g of sodium dodecylbenzenesulfonate, followed by emulsifying and dispersing. The resulting emulsified dispersion was mixed with 100g of a photographic emulsion containing 5.6 × 10 ^-2 mol of silver bromide and 10g of gelatin and 3ml of a 4% aqueous solution of 2-hydroxy-4,6-dichloro-s-triazine sodium salt as a hardener and then applied to a film of cellulose triacetate in a coating thickness of 2.5 microns.

The thus obtained film was exposed and then subjected to the same developing processings as those of Example 1 but using the following color developing solution and effecting the treatment in 14 minutes, thus obtaining a sharp magenta color image.

______________________________________ IX) Color Developing Solution 4-Amino-3-methyl-N,N-diethylaniline 2.5g Hydrochloride Sodium Sulfite (anhydrous) 10 g Sodium Carbonate (monohydrate) 47 g Potassium Bromide 2 g Water to 1000 ml (pH = 10.5) ______________________________________

The wavelength of the absorption maximum of the each film was as shown in Table 7.

TABLE 7 ______________________________________ Coupler and Absorption Maximum of the Developed Color Image ______________________________________ Coupler Wave Coupler Wave Coupler Wave No. Length No. Length No. Length ______________________________________ (mμ) (mμ) (mμ) 1 543 2 551 3 552 4 552 5 552 6 546 7 552 8 545 9 545 10 546 11 552 12 545 13 531 14 548 15 16 17 18 19 545 20 552 21 22 23 547 24 545 25 552 26 543 27 552 28 540 29 ______________________________________

EXAMPLE 6

Onto a transparent support of cellulose triacetate were coated, as a first layer, a red-sensitive silver iodobromide emulsion containing 1-hydroxy-2-tetradecylnaphthamide in a thickness of 5.0 microns and, as a second layer (coated silver amount: 2.12 × 10 ^-2 mol/m ² ; coated coupler amount: 1.8 × 10 ^-3 mol/m ² ), a gelatin containing 2,5-di-t-octylhydroquinone in a thickness of 1.0 micron.

17g of Coupler 23 of the invention, 2.0g of 1(2,4,6-trichlorophenyl)-3-((2-chloro-5-tetradecyloxycarbony l)anilino)-4-( α-naphthylazo)-5-pyrazolone, 12ml of tricresyl phosphate and 50ml of ethyl acetate were heated at 60°C and dissolved. The resultant solution was added to 150ml of an aqueous solution containing 15g of gelatin and 0.4g of sodium dodecylbenzenesulfonate at 60°C and the mixed solution was vigorously and mechanically stirred using a homogenizer to obtain an emulsified coupler dispersion. The resulting emulsion was mixed with 500g of a green-sensitive photographic emulsion containing 3 × 10 ^-1 mol of silver iodobromide (silver iodide 6 mol%, silver bromide 94 mol%) and 30g of gelatin, to which 5ml of a 3% acetone solution of the sodium salt of 2-hydroxy-4,6-dichloro-s-triazine as a hardener was then added, and the pH was finally adjusted to 7.0. The emulsion was coated as a third layer (coated silver amount: 1.85 × 10 ^-2 mol/m ² ; coated coupler amount: 1.74 × 10 ^-3 mol/m ² including 1.59 × 10 ^-3 mol/m ² of Coupler 23) onto the above described coating in a coating thickness of 5.1 microns on dry basis. Furthermore, onto the resulting coating were coated a gelatin mixture containing yellow colloidal silver and 2,5-di-t-octylhydroquinone in a thickness of 1.5 microns, a blue-sensitive silver iodobromide photographic emulsion containing α-(p-methoxybenzoyl)-α-(5,5-dimethyl-3-hydantoinyl)-2-chlo ro-5 -(γ-(2",4" -di-t-amylphenoxy)-butylamido)acetanilide as a fifth layer (coated silver amount: 1.0 × 10 ^-2 mol/m ² ; coated coupler amount: 1 × 10 ^-3 mol/m ² ) in a thickness of 5.0 microns and a protective layer of gelatin in a thickness of 1.0 micron as an uppermost layer, thus obtaining a color negative light-sensitive material.

When this film was exposed and subjected to the following development, an excellent color negative having a high sensitivity and good gradation and image quality was obtained. The density of blue light was substantially constant and independent of the degree of exposure to green light, and the color correction was suitable.

______________________________________ X) Color Development 1. Color Development 38°C 3 min 2. Stopping " 1 min 3. Water Washing " 1 min 4. Bleaching " 2 min 5. Water Washing " 1 min 6. Fixing " 2 min 7. Water Washing " 1 min 8. Stabilizing Bath " 1 min XI) Color Developing Solution Sodium Hydroxide 2 g Sodium Sulfite 2 g Potassium Bromide 0.4g Sodium Chloride 1 g Borax 4 g Hydroxylammonium Sulfate 2 g Ethylenediaminetetraacetic Acid 2 g 4-Amino-3-methyl-N-ethyl-N-(β- hydroxyethyl)aniline Monosulfate 4 g Monohydrate Water to 1000 ml XII) Stopping Solution Sodium Thiosulfate 10 g Ammonium Thiosulfate (70%) 30 ml Sodium Acetate 5 g Acetic Acid 30 ml Potassium Alum 15 g Water to 1000 ml XIII) Bleaching Solution Ferric Sodium Ethylenediaminetetra- 100 g acetate Dihydrate Potassium Bromide 50 g Ammonium Nitrate 50 g Boric Acid 5 g Ammonia Water to adjust pH to 5.0 Water to 1000 ml XIV) Fixing Solution Sodium Thiosulfate 150 g Sodium Sulfite 15 g Borax 12 g Glacial Acetic Acid 15 ml Potassium Alum 20 g Water to 1000 ml XV) Stabilizing Bath Boric Acid 5 g Sodium Citrate 5 g Sodium Metaborate (tetrahydrate) 3 g Potassium Alum 15 g Water to 1000 ml ______________________________________

EXAMPLE 7

Onto a film base of polyethylene terephthalate having a thickness of 0.15 micron were coated, in order, a first layer of an n-hexyl half ester of a copolymer of vinyl methyl ether and maleic anhydride (1:1 in molar ratio; molecular wt.: about 50,000) and having a thickness of 20 microns, a second layer of a 50% hydrolysate of polyvinyl acetate (molecular wt.: about 100,000) and having a thickness of 12 microns, a third layer of part by weight of an acid-treated gelatin and 1 part by weight of poly-N-n-butyl-6-methyl-3-vinylpyridinium bromide (molecular wt.: about 50,000) and having a thickness of 7 microns, a fourth layer of 10 parts by weight of rutile type titanium oxide and 1 part by weight of gelatin and having a thickness of 12 microns and then a fifth layer of 1 part by weight of carbon black and 5 parts by weight of gelatin and having a thickness of 3 microns.

5g of the sodium salt of Coupler 16 was dissolved with heating in a mixed solvent of 70ml of water and 30ml of 2-methoxyethanol and the resulting solution was added with agitation to 250g of an aqueous solution containing 0.1g of finely dispersed colloidal silver and 30g of gelatin at 50°C. The resulting mixture was cooled at 5°C and set, cut in square rods of about 5mm, washed with an aqueous solution containing 0.6g of magnesium sulfate per 1000ml at 5°C for 5 hours, heated for redissolving at 40°C, mixed with 10ml of a 3% methanol solution of triethylene phosphamide and 15ml of a 5% aqueous solution of saponin and then coated, as a sixth layer, onto the above described coating in a thickness of 7.5 microns on dry basis.

After an intermediate layer of 1 part by weight of 2,5-di-t-octylhydroquinone and 20 parts by weight of gelatin and having a thickness of 1 micron was coated onto the thus resulting coating, a green-sensitive emulsion optically sensitized with the sodium salt of anhydro-5'-diphenyl-3,3'-disulfopropyl-9-ethyloxacarbocyanin e hydroxide was applied as an eighth layer to the intermediate layer in a thickness of 4 microns. This emulsion contained 0.28 mol of silver iodobromide (iodine content 3 mol%, average grain size 0.6 micron) and 72g of gelatin per kg. Finally a gelatin layer of 1 micron was coated as an uppermost layer to thus obtain a light-sensitive material. The resulting light-sensitive material was exposed stepwise for sensitometry through, as a cover, a sheet of cellulose triacetate of a thickness of 0.1mm.

Between the cover sheet and emulsion surface, a viscous treating solution having the following composition was spread in a thickness of 0.15mm:

Developer Distilled Water 1000 ml Ascorbic Acid 0.2 g 4-Amino-N-ethyl-N-β-hydroxyethylaniline 25 g Sulfate Potassium Hydroxide 35 g Benzotriazole 0.02g Hydroxyethyl Cellulose 30 g Carbon Black 45 g

After about 30 seconds after the spreading, a magenta image appeared gradually and it was observed from the side of the terephthalate base that the image formation was accomplished in about 4 minutes.

While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.