05/293719

04/22/1975

09/29/1972

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Fuji Photo Film Co., Ltd. (Minami Ashigara-shi, Kanagawa, JA)

430/372

430/393

G03C7/30; G03C7/42; G03C7/16; G03C5/32

96/60,6BF,22

Mason, Processing Chemistry, 1966, pp. 210-211, 265-266..

Kelley, Mary F.

Sughrue, Rothwell Mion Zinn And Macpeak

What is claimed is

1. A process for developing a color photographic material having a waterproof support wherein the material is subjected to a color development process and then simultaneously bleached, fixed and stabilized with an oxidizer, a silver halide solvent and a compound containing an aldehyde group or a methylol group, wherein the improvement consists essentially of color developing said material and then simultaneously bleaching, fixing and stabilizing said photographic material by processing the color photographic material in a blix-stabilizing bath containing a water-soluble ferric complex salt of an organic acid, a solvent for silver halide, and 0.05 to 5.0 g. per liter of said bath of a water-soluble compound having an aldehyde group or a methylol group and being selected from the group consisting of compounds represented by the formula R--CHO wherein R represents an alkyl group, an aryl group, an allyl group or a heterocyclic group, compounds represented by the formula OHC--R'--CHO wherein R' represents a direct bond, a divalent aliphatic group or a divalent aromatic group and compounds represented by the formula R"--CH₂ OH wherein R" represents an aliphatic group, an aromatic group, or a heterocyclic group, said blix-stabilizing bath having a pH within the range of about 5.5 to about 7.5.

2. The process of claim 1 wherein said water-soluble compound having an aldehyde group or a methylol group is a compound represented by the formula

3. The process of claim 1 wherein said water-soluble compound having an aldehyde group or a methylol group is a compound represented by the formula

4. The process of claim 1 wherein said water-soluble compound having an aldehyde group or a methylol group is a compound represented by the formula

5. The process of claim 1 wherein the pH of said blix-stabilizing bath is in the range of from 6.0 to 7.0.

6. The process of claim 1, wherein said organic acid has the general formula

7. The process of claim 5, wherein said organic acid is malonic acid, tartaric acid, ethylmalonic acid, malic acid, fumaric acid, diglycolic acid, thioglycolic acid, ethyliminodipropionic acid, nitrilotriacetic acid, ethylenediaminetetraacetic acid, aminotriacetic acid, ethylenedithioglycolic acid, or dithioglycolic acid.

8. The process of claim 1, wherein said solvent for silver halide is a thiosulfate, a thiocyanate, an organic sulfur-containing dibasic acid, or an organic diol.

9. The process of claim 2, wherein said water soluble compound having a aldehyde group or a methylol group is formaldehyde, paraformaldehyde, trioxymethylene, glycolaldehyde, methylal, chloral, acetaldehyde, aldol, propiolaldehyde, acrolein, dibromoacrolein, crotonaldehyde, salicylaldehyde, gluoxylic acid, mucochloric acid, mucobromic acid, arabinose, xylose, glyceraldehyde, furfural or precursors thereof.

10. The process of claim 3, wherein said water soluble compound having an aldehyde group or a methylol group is glyoxal, succinaldehyde, tartardialdehyde, terephthalaldehyde, glutaraldehyde, α-methylglutaraldehyde, cyclopentanedicarboxyaldehyde, or precursors thereof.

11. The process of claim 4, wherein said water soluble compound having an aldehyde group or a methylol group is N-methylolurea, N,N'-dimethylolurea, N-methylolmethylene bis-monoethylurea, N'-methylol-N,N'-dimethylolurea, methylohydantoin, dimethylolmelamine, monomethylol dimethylhydantoin, hydroxydimethylbuiret, trihydroxymethylbuiret, 2,2,6,6-tetramethylolcyclohexanol, methyloldicyandiamide, 3-hydroxy-2,2-dihydroxymethylpropionic acid, 2-nitro-2-methyl-1,3-propanediol.

12. The process of claim 1, wherein said blix-stabilizing bath additionally contains a water-soluble fluorescent brightening agent.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method for processing a color photographic material and more particularly to a color photographic process for forming stable color photographic images.

2. Description of the Prior Art

It is well known in the color photographic field to form color photographic images by subjecting multilayer color photographic materials; after exposure, to such processings as development, bleaching, fixing, etc. Generally these color photographic materials have, on one side of the support, three spectrally sensitized emulsion layers, i.e., a blue-sensitive emulsion layer, a green-sensitive emulsion layer, and a red-sensitive emulsion layer. The color photographic materials have further, where appropriate, non-sensitive subsidiary layers such as a yellow filter layer, an antihalation layer, etc.

Each of the light-sensitive emulsion layers of the color photographic materials may contain a ketomethylene type coupler for forming yellow images, a pyrazolone coupler for forming magenta images, or a phenolic or naphtholic coupler for forming cyan images.

The exposed multilayer color photographic materials are usually subjected, after color development, to a series of processings such as bleaching, fixing, water washing, etc., and then dried. Since it requires a considerably long period of time for such a color photographic process, it has recently been desired to shorten the processing time and thus various attempts have been proposed for such a purpose. For instance, it has been proposed to shorten or simplify a conventional five-bath system composed of color development, fixing, bleaching, washing and stabilization steps by employing a blix step, that is, a step which combines the bleaching step and the fixing step. The three-bath system thus proposed is composed of a color development, blix, (washing) and stabilization step, and by employing such a three-bath system the color photographic processing period may be shortened to some extent as compared with the aforesaid five-bath system. However, even such a three-bath system requires a considerable processing time.

SUMMARY OF THE INVENTION

An object of this invention is, therefore, to provide a simplified and shortened photographic process for forming stable color photographic images.

The aforesaid object of this invention can be attained by processing a color photographic material having a waterproof support, after color development, in a bath which simultaneously bleaches, fixes, and stabilizes the color photographic materials.

The novel blix-stabilizing bath used in the process of this invention contains an oxidizing agent for silver, a solvent for silver halide, and a stabilizer for color images.

DETAILED EXPLANATION OF THE INVENTION

As an oxidizing agent for silver, potassium ferricyanide is conventionally used for bleaching in the conventional five-bath system. However, the use of potassium ferricyanide is accompanied with disadvantages, i.e., it is difficult to form a stable system of potassium ferricyanide together with a thiosulfate which is a solvent for silver halide, and the use of potassium ferricyanide causes problems of the waste liquid leading to water pollution. Accordingly, it is not appropriate to employ such a ferricyanide in the blix-stabilizing bath of this invention. Therefore, in the process of this invention, a water-soluble ferric complex salt of an organic acid is used as the oxidizing agent for silver. Such a ferric complex salt has the advantages that it is stable with a thiosulfate, is excellent in chemical and photochemical stability, has less toxicity to humans, and can be readily regenerated after use.

The organic acid capable of forming the water-soluble ferric complex salt of the acid used in this invention includes a compound represented by the following general formula,

HOOC--R ₁ --X--R ₂ --COOH

or ##SPC1##

wherein X represents a hydrocarbon group, an oxygen atom, a sulfur atom, or ##SPC2##

R ₁ , r ₂ , r ₃ , r ₄ , and R ₅ each represents a substituted or unsubstituted hydrocarbon group; and R ₆ represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group.

Specific examples of suitable organic acids are malonic acid, tartaric acid, ethylmalonic acid, malic acid, fumaric acid, diglycolic acid, thioglycolic acid, ethyliminodipropionic acid, nitrilotriacetic acid, ethylenediaminetetraacetic acid, aminotriacetic acid, ethylenedithioglycolic acid, dithioglycolic acid, and the like. Such an organic acid readily forms a stable ferric chelate compound with a tri-valent iron salt such as ferric chloride, ferric sulfate, or iron alum in an aqueous medium. Accordingly, in the present invention, the aforesaid organic acid may be used together with the tri-valent iron salt in an aqueous medium or a ferric complex salt of the organic acid may be used. Among them, the ferric complex salt of polyaminocarboxylic acid, for example, ethylenediaminetetraacetic acid (EDTA), is most generally used because such a complex salt has a high bleaching power, is stable and is easily obtained commercially.

The processing bath in this invention can also contain a bleach-accelerator such as potassium bromide, potassium iodide, sodium iodide, polyalkylene oxide, 2-mercaptoimidazole, 3-mercapto-1,2,4-triazole, dithioglycol, a copper complex salt of an organic acid such as cupric complex salt of EDTA, a cobalt complex salt of an organic acid such as cobaltic complex salt of EDTA, thiourea, ethylene thiourea, a selenium compound such as sodium selenosulfate, etc. Also, the processing bath can further contain an anti-bleach-fogging agent such as a hydroxylamine salt, p-aminophenol, hydroxymorpholine, ascorbic acid, 1-phenyl-3-pyrazolidone, semicarbazide, hydrazine salt, etc.

As the fixing component for the blix-stabilizing bath in this invention, a silver halide solvent is employed. Examples of such solvents are thiosulfates such as sodium thiosulfate, ammonium thiosulfate, etc., thiocyanates such as potassium thiocyanate, etc., sulfur-containing organic dibasic acids such as bisthioglycollic acid, etc., organic diols such as 3-thia-1,5-pentanediol, etc., and imidazolidine thion. Sodium sulfite, etc., can be used in combination therewith as a fixing aid.

In order to find the compounds capable of being used together with the above-mentioned bleaching component and fixing component and having the function of improving the stability of the color images, the inventor investigated the following compounds. That is to say, there are ultraviolet absorbents such as water-soluble sulfo compounds, monoazo compounds, etc.; aldehyde compounds; combinations of aldehyde compounds and ultraviolet absorbents or fluorescent brightening agents; cysteine; methylol; methylolbiuret; methylolurea; biuret derivatives as are described in French Pat. No. 1,290,631; thiol compounds; polyhydroxy compounds; combinations of aldehydes and polycarboxylic acids; carbohydrazide; water-soluble salts of cysteine; water-soluble salts of copper, manganese, uranyl, nickel, lead, or zinc; glucoheptonic acid; glucoheptonate; glycine; glycylglycine; N,N-dialkylglycine; and adducts of aldehyde or methylketones and alkali metal sulfites.

As a result of the overall investigation of the systems resulting when the above compounds are used together with the bleaching component and the fixing component indicated above, the stability of the solution, the function of stabilizing color images, the influence on the photographic properties and physical properties of photographic materials, and the toxicity to humans, it has been discovered that the water soluble compounds having an aldehyde group or a methylol group represented by the general formula (I), (II), or (III) shown below are effective.

General formula (I) R -- CHO

wherein R represents a hydrogen atom, an alkyl group, an allyl group, an aryl group, or a heterocyclic group, where each of said groups can be substituted.

Specific examples of the compounds represented by general formula (I) are formaldehyde, paraformaldehyde, trioxymethylene, glycolaldehyde, methylal, chloral, acetaldehyde, aldol, propiolaldehyde, acrolein, dibromoacrolein, crontonaldehyde, salicylaldehyde, glyoxylic acid, mucochloric acid, mucobromic acid, arabinose, xylose, glyceraldehyde, furfural, etc. The precursors of the above compounds may also be used. Examples of such precursors are hexamethylenetetramine etc., described in German Pat. Nos. 539,372 and 600,665.

General formula (II) OCH--R'--CHO

wherein R' represents a direct bond, a divalent aliphatic group, or a divalent aromatic group.

Specific examples of compounds represented by general formula (II) are glyoxal, succinaldehyde, tartardialdehyde, terephthalaldehyde, glutaraldehyde, α-methylglutaraldehyde, cyclopentane-dicarboxyaldehyde, and dialdehydes as disclosed in British Pat. No. 1,102,001 and French Pat. 1,543,694. The precursors of the above compounds such as 2,5-dialkoxytetrahydrofuran, etc., described in Japanese Pat. Publication No. 27,570/'64 can also be used.

General Formula (III) R"--CH ₂ OH

wherein R" represents an aliphatic group, an aromatic group, or a heterocyclic group.

Specific examples of the compounds represented by general formula (III) are N-methylolurea, N,N'-dimethylolurea, N-methylolmethylene bismonoethylurea, N'-methylol-N,N'-dimethylolurea, methylolhydantoin, dimethylolmelamine, monomethylol dimethylhydantoin, hydroxydimethylbiuret, trihydroxymethylbiuret, 2,2,6,6-tetramethylolcyclohexanol, methyloldicyandiamide, compounds such as 3-hydroxy-2,2-dihydroxymethylpropionic acid, etc., described in British Pat. No. 1,116,944, 2-nitroethanol derivatives such as 2-nitro-2-methyl-1,3-propanediol described in Japanese Pat. application No. 67,799/'69, etc.

The novel blix-stabilizing bath used in the process of this invention contains, as fundamental components, the water-soluble ferric complex salt of the organic acid, the solvent for silver halide, and the water-soluble compound having an aldehyde group or a methylol group. The discovery of such a blix-stabilizing bath is quite astonishing on considering the difficulty of using an oxidizing agent such as a water-soluble ferric complex salt of an organic acid and a reducing agent such as formaldehyde simultaneously in a mono-processing bath. However, the inventors have succeeded in using the both components in a stable manner effectively in a processing bath by adding a silver halide solvent, such as sodium thiosulfate, to the system and adjusting the pH of the solution.

If the pH of the blix-stabilizing bath used in this invention is too low, the bath is inferior in bleaching power and the stabilizing effect for images and the density of the color images is sometimes reduced, while if the pH thereof is too high, the bleaching power is reduced. The pH of it is suitably about 5.5 to about 7.5, preferably 6.0 to 7.0. Any known pH controlling agent may be used, but usually a carbonate is employed for this purpose.

The amount of the water-soluble compound having an aldehyde group of a methylol group depends on the nature of the compound and is usually determined upon considering the stabilizing effect for images and the stability of the solution. For instance, when a 37% aqueous solution of formaldehyde is employed, a preferred amount of the solution is 2 to 6 ml per liter of the bath solution, while when 2% aqueous solution of dimethylurea is employed, a preferred amount thereof is 4 to 15 ml per liter of the bath solution. In general, a suitable amount of the water-soluble compound having an aldehyde group or a methylol group is in the range of from 0.05 to 5 g per liter of the solution.

The amounts of the bleaching component and the fixing component are easily determined according to the characteristics desired. Generally from 40 to 60 g per liter of the bleaching component and from 100 g to 200 g per liter of the fixing component, respectively, are employed.

Furthermore, a water-soluble fluorescent brightening agent can be incorporated in the blix-stabilizing composition of this invention to add a color image stabilizing action and brightening action.

Also, a surface active agent may be incorporated in the bath composition as a draining agent or an extender.

Any color photographic material such as a color photographic negative film, color photographic paper, reversal color photographic film, color reversal paper, etc., can be used in the process of this invention.

In a color negative film and color reversal film, an anti-halation layer, a red-sensitive emulsion layer containing a cyan coupler, a green-sensitive emulsion layer containing a magenta coupler, a yellow filter layer, a blue-sensitive emulsion layer containing a yellow coupler, and a gelatin protective layer are formed on a support, in this order.

In a color photographic paper, a blue-sensitive emulsion layer containing a yellow coupler, a green-sensitive emulsion layer containing a magenta coupler, a red-sensitive emulsion layer containing a cyan coupler, and a gelatin protective layer are formed on a support, in this order.

Also, a packet-type color photographic material having a single light-sensitive layer having dispersed therein a packet containing a blue-sensitive emulsion and a yellow coupler, a packet containing a green-sensitive emulsion and a megenta coupler, and a packet containing a red-sensitive emulsion and a cyan coupler can be used in the process of this invention.

In the present invention, the support for the color photographic material must absorb no or substantially no water or photographic processing solution. Such supports are well known in this art as waterproof or water-repellent support. Examples of such supports are cellulose nitrate films, cellulose acetate films, polystyrene films, polycarbonate films, polyester films etc., and such films further containing a white pigment, cellulose films opacified by dispersing a fine foam therein as described in U.S. Pat. No. 2,422,008, a metallic sheet such as an aluminum sheet, baryta-coated papers having incorporated in the paper pulp polygalactomannan as described in German Pat. No. 1,262,756, supports composed of acyl cellulose fibers as described in U.S. Pat. Nos. 3,098,786 and 3,132,944, and the so-called resin-coated papers prepared by coating both sides of a paper with a waterproof synthetic resin such as polyethylene, as described in U.S. Pat. No. 3,448,000, French Pat. No. 1,517,560, German Pat. Nos. 1,261,746 and 1,809,606, and British Pat. No. 1,183,613. Ordinary baryta-coated papers are unsuitable in the process of this invention since they require water washing for a long period of time to remove chemicals absorbed therein during photographic processings.

The photographic layers applied onto the support may be any of the conventionally known ones. That is to say, as the hydrophilic colloid forming each of the photographic layers, there can be used gelatin, albumin, cellulose derivatives such as cellulose hydrates, polyvinyl alcohol, etc. These photographic layers are preferably hardened by hardening agents. Known silver halide emulsions used in this invention. Each silver halide emulsion may contain, if desired, conventional additives such as a sensitizer, a sensitizing dye, a stabilizer, etc.

Moreover, the photographic materials used in this invention may contain conventional diffusion resistant couplers, e.g., ketomethylene type yellow couplers, pyrazolone magenta couplers, phenolic or naphtholic cyan couplers, etc. Specific examples of such couplers are given below:

Yellow couplers:

ω-benzoylacet-(2-n-pentadecyloxy)-4-sulfoanilide, N-phenyl-N'-(p-acetaminophenol)-urea, ethyl-p-benzoylacetaminobenzene sulfonate, ω-benzoylacet-2,5-dichloroanilide, N,N'-di-(acetoacetamino)-3,3'-dimethyldiphenyl, N-amyl-p-benzoylacetaminobenzene sulfonate.

Magenta couplers:

1-phenyl-3-benzamidopyrazole-5-one, 1-p-nitrophenyl-3-n-amyl-5-pyrazolone, 1-phenyl-3-acetylamino-5-pyrazolone, 2-cyanoacetyl-5-benzoylaminocoumarone, and 2-cyanoacetylcoumarone-5-sulfodimethylamide.

Cyan couplers:

1-stearoylamido-4-(1'-hydroxy-2'-naphthoylamido)-benzene -3-sulfonic acid, 1-naphthol-5-sulfocyclohexylamide, 5-(n-benzyl-N-n-valerylamino)-1-naphthol, 2,4-dichloro-5-palmithylamino-1-naphthol, 2-benzoylamino-5-methylphenol, and 2,2'-dihydroxy-5,5'-dibromostilbene.

These couplers can be incorporated into the hydrophilic colloid in any conventional manner.

According to the process of this invention photographic materials are, after color development, processed in the blix-stabilizing bath and then washed and dried. As the color developing solution used for developing the photographic materials, an alkaline aqueous solution containing a primary aromatic amine developing agent is used. Any such conventional developing agent as used in present color developing processes may be used in the present invention. For example, there are illustrated phenylenediamine compounds and p-aminophenol compounds. Known additives conventionally used in this field may be added to the developing solution. For example, such additives as a sulfite, a bisulfite, a carbonate, a bromide, an iodide, an amine, benzyl alcohol, etc.

Of course, the processing steps of this invention vary to some extent according to the nature and use of the photographic materials to be processed as shown below. In the case of processing color negative films, after developing the color photographic films in a color developing solution containing a color developing agent such as 2-amino-5-diethylaminotoluene hydrochloride together with benzyl alcohol, sodium metaborate, potassium bromide, etc., the photographic films are immediately processed in a stopping solution containing glacial acetic acid and, after washing, processed in the blix-stabilizing bath of this invention followed by washing and drying.

In the case of processing color photographic papers, after developing the color photographic papers in a color developing solution containing a color developing agent such as p-hydroxyethylaminoaniline sulfate together with benzyl alcohol, sodium metaborate, hydroxylamine sulfate, sodium hydroxide, etc., the color photographic papers are immediately washed in a short period of time and then processed in the blix-stabilizing bath of this invention followed by washing and drying.

In the case of processing color reversal films or color reversal papers, after developing the color reversal materials in a black and white developing solution containing a developing agent such as metol, hydroquinone, and phenidone together with sodium carbonate, potassium thiocyanide, potassium bromide, etc., the photographic materials are immediately processed in a stopping solution containing glacial acetic acid, washed, subjected to a reversal exposure, subjected to color development in a color developing solution containing a color developing agent such as 2-amino-5-diethylaminotoluene hydrochloride together with benzyl alcohol, sodium tertiary phosphate, sodium hydroxide, ethylenediamine, potassium bromide, etc., processed in the blix-stabilizing bath of this invention, washed, and then dried.

Now, the advantages obtained by the process of this invention will be described in greater detail.

1. Reduction of the number of processing baths and shortage of processing period of time:

As an example, in the case of using color photographic papers prepared by coating waterproof papers with the above-indicated photographic emulsions, the number of processing steps and the time required for each step in the conventional five-bath and three-bath system are compared with those in the two-bath system of this invention as shown in the following table, in which the processing temperature is 24° C in each step.

______________________________________ Five-bath system Three-bath system Two-bath system ______________________________________ 1. Color deve- 1. Color deve- 1. Color deve- lopment lopment lopment 6 min. 6 min. 6 min. 2. Stop-fixing 2. Blixing 2. Blix-stabili- 2 min. 6 min. zation 6 min. 3. Washing 3. Washing 3. Washing 2 min. 3 min. 2 min. 4. Bleaching 4. Stabilization 2 min. 4 min. 5. Washing 2 min. 6. Hardening- fixing 4 min. 7. Washing 3 min. 8. Stabilization 4 min. 8 steps 4 steps 3 steps 25 min. 19 min. 14 min. ______________________________________

As is clear from the above table, the number of steps in the two-bath system of this invention is less than half of those in the five-bath system and is less than the number of the steps in the three-bath system by one step. Furthermore, the processing time in the two-bath system of this invention is shortened about 40% as compared to the processing period in the five-bath system and about 25% as compared to the processing period in the three-bath system. Furthermore, in the process of this invention it is possible to finish the whole process within 5 minutes when the processing temperature is increased to 35° - 38° C.

Such a reduction in the number of processing baths and shortening of the processing time are quite effective to compactness the time required for processing in an automatic developing machine, to reduce the processing cost, increase the processing capacity, and increase the efficiency of operation.

2. Stabilization of the color images to heat, humidity, and light:

In the conventional systems a stabilization bath is employed before the drying step as an independent step, but in the system of this invention a stabilization effect similar to or better than that obtained by the conventional step is obtained by the processing in the blix-stabilization bath. That is to say, when the color paper processed according to the process described in Example 2 after stepwise exposure through a red filter, a green filter, and a blue filter, and a color paper processed in the same way as in Example 2 except that only formalin was removed from the blix-stabilizing composition, were placed for 10 days in a chamber maintained at a temperature of 60° C and a humidity of 70%, the color densities, i.e., the cyan density, magenta density, and yellow density, of the color papers were measured, and compared. The yellow fog density of the paper processed in the bath containing formalin was 0.08, while that of the paper processed in the bath containing no formalin was 0.12. This shows that the blix-stabilizing solution of this invention prevents increased of yellow stain by heat and humidity with the passage of time.

Furthermore, when the above samples subjected to the described processings were exposed to a xenon lamp for 12 hours, the yellow density of the sample obtained by the process using the processing bath containing no formalin was reduced to 0.87, while the yellow density of the sample processed in the processing solution containing formalin was 1.00, which shows that the color image obtained with the blix-stabilizing bath was prevented from being faded by light.

An aldehyde compound is believed to stabilize unreacted couplers in emulsion layers by reaction with them and at the same time it is believed that it has the effect of preventing change of the color images due to moisture by the hardening action thereof.

3. Prevention of the damage of films during processing and speed up of drying by the hardening action:

The emulsion layers softened during the development step, washing step, etc., are hardened again by the hardening action of the compound having an aldehyde group or a methylol group in the blix-stabilizing bath and thus the emulsion layers are also prevented from being swollen in the blix-stabilizing bath and during washing. Therefore, the occurrence of mechanical damage such as scratches, reticulation, etc., to the emulsion layers during processing and washing can be effectively prevented. Furthermore, because the emulsion layers will not be melted by the action of the hardening action even if the photographic materials are processed at a high temperature, it is possible to dry the photographic material at high temperature in a shortened period of time.

4. Prevention of the generation of irritative gases:

In the conventional system of employing a stabilizing bath containing formalin, etc., directly before drying, irritative formalin vapors are formed during drying. Such a problem does not occur in the process of this invention since a washing treatment is conducted after the blix-stabilizing process.

The stabilization action for color images tends to be reduced when the washing after the blix-stabilizing process is conducted for a long period of time but there is no such difficulty since in the process of this invention color photographic materials having waterproof supports are employed.

Now, the invention will be described in greater detail by reference to the following examples. Unless otherwise stated, all parts and percents are by weight.

EXAMPLE 1

A polyethylene-coated waterproof paper prepared as described in U.S. Pat. No. 3,448,000 was coated with a gelatin under coat and then coated in succession with a blue-sensitive silver iodobromide emulsion layer containing ethyl-p-benzoylacetaminobenzene sulfonate, a green-sensitive silver chlorobromide emulsion layer containing 1-p-nitrophenyl-3-n-amyl-5-pyrazolone, a red-sensitive silver chlorobromide emulsion layer containing 2,4-dichloro-5-palmitylamino-1-naphthol, and a protective layer of gelatin to provide a multilayer color photographic paper. Then the color paper was, after exposure, processed at 29.5° C in the following way:

Color development 6 min. Washing 30 sec. Blix-stabilization 3 min. Washing 2 min. Color developing solution: Sodium tertiary phosphate (12H ₂ O) 15 g Sodium metaborate 10 g Anhydrous sodium sulfite 1 g Hydroxylamine sulfate 2 g Potassium bromide 0.5 g 6-Nitrobenzoimidazole nitrate (0.2%) 20 ml Benzyl alcohol 40% solution 45 ml Sodium hydroxide 1.2 g 4-Amino-N-ethyl-N-(β-methasulfon- amidoethyl)-m-toluidine sulfate 8.5 g Water to 1 liter pH 10.0 Blix-stabilizing solution: Ferric chloride 6H ₂ O 2.9 g 2-Sodium ethylenediaminetetra- acetic acid 40 g Anhydrous sodium carbonate 16 g Anhydrous sodium thiosulfate 150 g Anhydrous sodium sulfite 10 g Formalin (37% formaldehyde) 4 ml Water to 1 liter pH 6.7

The processing time was shortened to about 12 minutes and the properties of the color image as well as the stability thereof to light and heat were not inferior to those in a conventional system employing individual bleaching, fixing, and stabilizing steps.

EXAMPLE 2

In place of the blix-stabilizing solution used in Example 1, a solution having the formula composition was used.

______________________________________ Ferric complex salt of EDTA 40 g Anhydrous sodium carbonate 3 g Anhydrous sodium thiosulfate 150 g Anhydrous sodium sulfite 10 g Formalin (37% formaldehyde) 4 ml Water to 1 liter pH 6.8 ______________________________________

Almost the same results as obtained in Example 1 were obtained.

EXAMPLE 3

In place of the blix-stabilizing solution used in Example 1, a solution having the following composition was employed.

______________________________________ Ferric complex salt of EDTA 50 g Anhydrous sodium carbonate 6 g Potassium bromide 12 g Thiourea 10 g Ammonium thiosulfate 100 g Tinopal GS 2 g Dimethylolurea (2% aqueous solution) 10 ml Water to 1 liter pH 6.8 (2.5°C) ______________________________________

Almost the same results as in Example 1 were obtained.

EXAMPLE 4

A cellulose triacetate film base having a thickness of 130 microns was coated in succession with an antihalation layer composed of colloidal silver, a red-sensitive silver iodobromide emulsion layer containing 2-chloro-4-(2-benzothiazoleazo)-1-naphthol, a green-sensitive silver iodobromide emulsion layer containing 1-[p-(p-tert-butylphenoxy)phenyl]-3-methyl-4-(p-hydroxypheny lazo)-5-pyrazo lone, a filter layer composed of yellow colloid silver, a blue-sensitive silver iodobromide emulsion layer containing N-(4-benzoylacetaminobenzenesulfonyl)-N-benzyl-m-toluidine, and a protective layer of gelatin to provide a color negative film. The color film was, after exposure, processed in the following way at 24° C.

______________________________________ Color development 14 min. Stop 4 min. Wash 4 min. Blix-stabilization 12 min. Wash 6 min. ______________________________________

The composition of the color developing solution used in the above processings was the same as that described in Example 1.

______________________________________ Stop solution: Glacial acetic acid 20 ml Anhydrous sodium sulfite 10 g Water to 1 liter pH 4.5 Blix-stabilizing solution: Ferric complex salt of EDTA 60 g Anhydrous sodium sulfite 10 g Anhydrous sodium thiosulfate 200 g Anhydrous sodium carbonate 5 g Monomethylol dimethylhydantoin 1 g Water to 1 liter pH 6.5 ______________________________________

The processing period of time was shortened and a color image stable to light and heat was obtained.

While the invention has been described in detail and in terms of 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.