IL32940A - Equipment and method for developing exposed color photographic emulsions - Google Patents

Description

Equipment and method for developing exposed eolor photographic emulsions Disclosure This invention relates generally to equipment and a method for developing color images in exposed photographic emulsions. More particularly, the invention in-volves a combination of solutions for treating the emulsions and the method of their use.

Conventionally, an exposed color photographic emulsion is developed by immersing it in the following succession of solutions and intermediate water washes: developing bath stop bath hardener bath (in the case of negative film) water wash bleaching bath water wash fixing bath water wash stabilizer bath (in the case of color print papers) In some cases, it is also necessary to immerse color print papers in a prewetting bath prior to its immersion in the developing bath and in some cases an additional washing bath is required between the developing bath and the stop bath.

On the other hand, in the case of certain AGFA color print papers, the bleaching and fixing baths are combined, thereby eliminating one water washing step.

In general, conventional processes and equipment require 8 successive steps and about 48 minutes' time for developing color negative film and require 6 to 10 successive steps and about 8 to 23 minutes' time for developing color print papers. Moreover, the numerous steps make it necessary to provide relatively complex apparatus for carrying out the various conventional processes. The conventional color developing apparatus is, for example, considerably more complex than that necessary for developing black and white photographic emulsions.

The object of this invention is to provide a relatively simple, inexpensive color developing method and equipment which are improved in that they facilitate developing exposed color emulsions by the use of fewer steps and in a shorter time than heretofore possible.

In general, the invention is carried out by providing a developing solution, a stop-fix solution (where film is to be developed), and a combined bleach-fix solution which is effective to bleach and fix both color print papers and color negative films. The ingredients and the relative pH of the solutions are so related that, in accordance with the method, after color print papers have been treated in the developing bath, they are transferred directly to the bleach-fix bath without intermediate washing; and similarly after a color negative film has been treated in the develop-ing bath, it is transferred to the stop-fix bath and then to the bleach-fix bath, both without intermediate washing.

Papers and negative film alike are washed and treated in a stabilizer bath following their treatment in the bleach- fix bath.

The developing method for color print papers thus requires four steps including a single wash while the process for color negative film requires five steps including a single wash.

In accordance with a more specific aspect of the invention, the equipment is in the form of a kit which includes three separate solutions which contain developing agents, respectively, for color negative film and each of two types of color print paper. A fourth solution is provided which is complemental in common to the other three.

A developing bath for a particular emulsion is provided by mixing a selected one of the first three solutions with the fourth. Also, the kit includes two further solutions which, when intermixed, provide the combined bleach-fix solution. This arrangement has numerous advantages set forth below.

Color photographic emulsion products generally fall into three categories: (1) color negative film, (2) color print papers of a type in which the color couplers are encapsulated in materials not readily soluble in water, these papers being referred to hereinafter as "Type A" papers, and (3) color print papers in which the color couplers are not so encapsulated, these papers being referred to hereinafter as "T e B " a ers .

Insofar as I am aware, the following is a list of all color negative films and color print papers now available to the industry in the United States and in foreign countries : Color Negative Films; Eastman KODACOLOR negative film Eastman EKTACOLOR negative film Eastman ECTACHRO E MS (when developed as a negative) Eastman Type 5251 color negative film A SC0C0L0R color film (when developed as a negative) (AGFA CN-17 is excepted, since this film is becoming obsolete and its replacement is not yet available.) Type A Papers: Eastman EKTAPRINT color print paper Eastman waterproof base color print paper ANSCOCOLOR color print paper Ferrania color print paper Sakura color print paper Type B Papers: AGFACOLOR color print paper FJUI color print paper Pavelle color print paper I have discovered that the developing solutions for developing the images in the emulsions of all of these negatives and papers have certain ingredients in common. These common ingredients are in aqueous solution and include gen-erally solvents for various salts in the developing bath, alkaline and acidic materials by which the pH of the developing bath is controlled, buffers which stabilize the bath against changes in pH, clarifying agents which prevent cloudiness or sludges forming from salts normally contained in water (such as sodium and potassium sulfates, carbonates, calcium carbonate, oxides, etc.). The common ingredients also include preservatives for the developing agent, restrainers for preventing excess development of unexposed silver halide in the emulsion, and agents which remove undesirable products of re-action produced during the developing process.

In addition to these common ingredients, a developing bath contains additional ingredients which are particularly adapted for developing either a color negative film or a Type A color print paper or a Type B color print paper. Thus, it is possible to provide a first solution containing the common ingredients and to provide separately three additional solutions, each containing ingredients adapted for use respectively with color negative film or Type A or Type B color print paper. When a selected one of the latter three solu-tions is mixed with a quantity of the common solution, a developing bath is produced which is particularly adapted for In accordance with the invention I provide such a common solution which preferably includes sodium hydroxide for increasing the solubility of the other salts in a given volume of water and which assists in obtaining a desired pH level in the solution. This solution also preferably includes sodium sulfite which preserves the developing agent later added to the common solution by restraining undesirable oxidation of the developing agent. The solution also preferably contains potassium bromide which restrains or prevents excess development of unexposed silver halide in the developing bath and prevents a stained appearance in the light or white portions of the ultimate color image.

Also included in the common solution is a "buffer" such as Borax or trisodium phosphate which stabilizes the developing bath against changes' in pH, and water conditioners which serve to prevent the formation of cloudiness or sludges by salts which may be contained in the water such as sodium and potassium sulfates, carbonates, calcium carbonate, oxides etc. Examples of such water conditioners are: Ethylene diamine tetra-acet c acid Hydroxyethyl ethylene diamine triacetic acid Potassium hydroxide Calgon Corp. "Calgon" (photo grade) Eastman Kodak "Antical No. 3" Laboratory Equipment Corp. "Lecanol" The compound ethylene diamine tetra-acctic acid is frequently referred to in the art by the abbreviation "EDTA". For the sake of convenience, this notation will be adopted hereinafter and in the claims.

The potassium hydroxide restrains clouding of the solution by maintaining a balance between the potassium and sodium salts and also assists in increasing the pH of the solution when first mixed. The other water conditioners are in the nature of wetting agents or sequestering agents. Preferably, hydroxylamine sulfate or hydroxylamine hydrochloride is included in the common solution to help remove undesirable products of reaction, such as hydrogen peroxide, which form during the developing process. Sodium chloride may be included to accelerate penetration of water insoluble encapsulating material for color couplers in certain types of negative film.

Following are four examples of suitable common solutions, these examples illustrating suitable combinations of ingredients and illustrating the relative ratios of the ingredients: Example I Water · 700.00 cc Sodium hydroxide 8.40 gm Hydroxyethyl ethylene diamine tri-acetic acid 3.00 gm "Borax" 27.50 gm Sodium sulfite Potassium bromide Hydroxylamine sulfate Potassium hydroxide Example II Water EDTA "Calgon" Sodium sulfite Sodium hydroxide Tri-sodium phosphate Potassium bromide "Lecanol " Example III Water Sodium hydroxide "Borax" Sodium sulfite Potassium bromide Sodium chloride Hydroxylamine hydrochloride "Antical No. 3" Example IV Water 800.00 cc Sodium hydroxide 7.25 gm "Borax" 27.50 gm Sodium sulfite 2.00 gm Potassium bromide 0.43 gm Sodium chloride 0.73 gm Hydroxylamine hydrochloride 1.20 gm "Antical No. 3" 2.40 gm Potassium hydroxide 4.50 gm A solution which, when added to one of the above common solutions, will produce a developing bath for a color photographic emulsion and will be referred to as an "activator" or "activator solution". An activator solution for producing a color negative developing bath contains a developing agent which converts the color couplers in the negative to dyes.

I have found that one developing agent is effective for so acting on the color couplers in all types of negative films listed above. This developing agent is 4-amino-N-ethyl-N (beta-methane-sulphonyl-amido-ethyl) -n-toluidine sulfate. This chemical is commercially available as Eastman Kodak "CD-3".

For the sake of convenience, this chemical will be identified herein as "CD", an abbreviation for "color developer . " CD penetrates the water-insoluble encapsulating materials for the color couplers in certain types of negative films a d is as well as negative filras whose color couplers are not so encapsulated.

The negative film activator preferably includes benzyl alcohol, which softens the color coupler encapsulating material, and another material which will hold the benzyl alcohol in aqueous solution. Examples of these other materials are diethylene glycol and Union Carbide "Carbo- ax" OS-200. The activator solution preferably includes a preservative for the developing agent, examples of which are sodium metabisulf te, citric acid, sodium bisul-f te, and acetic acid, these ingredients also serving to control the pH of the solution. The solution also preferably contains potassium bromide which serves the same purpose as in the common solution and potassium iodide which prevents an excessive amount of yellow coupling during the developing process. The solution may also be provided with a wetting or sequestering agent of the types mentioned above with respect to the common solution.

Following are four examples of suitable activator solutions for color negative films, these examples illustrating suitable combinations of ingredients and illustrating the relative ratios of the ingredients: Example I Acetic acid (99%) "Carbo-Wax" OS-200 Benzyl alcohol Sodium metabisulfite CD Potassium iodide (0.1% solution) Potassium bromide Water in sufficient quantity to provide a pH of about 10.70 for a developing bath formed by mixing this Example with a selected common solution Example II Diethylene glycol Benzyl alcohol CD Water in sufficient quantity to provide a pH of about 10.75 for a developing bath formed by mixing this Example with a selected common solution Example III CD 5.0 gm Citric Acid 1.3 gm Potassium bromide 1.0 gm Water in sufficient quantity to provide a pH of about 10.75 for a developing bath formed by mixing this Example with a selected common solution Example IV "Carbo-Wax" OS-200 5.25 cc Benzyl alcohol 5.25 cc CD 5.25 gm Potassium bromide 1.08 gm Potassium iodide (.01% solution) 5.30 cc "Lecanol" 1.00 cc Sodium metabisulfite 0.40 gm Sodium bisulfate 2.10 gm Water in sufficient quantity to provide a pH of about 10.77 for a developing bath formed by mixing this Example with a selected common solution An activator solution for producing a color print paper developing bath contains a developing agent which converts the color couplers in the paper to dyes; and in the case of Type A papers, the activator contains benzyl alcohol and another material which will hold the benzyl alcohol in aqueous solution, these materials being substantially the same as those discussed above with respect to the color negative film developing bath. The paper developing bath may also include preservatives for the developing agent, pH control ingredients, and color coupling controllers such as a ferrocyanide salt.

In general, the chemical identified as "CD" (or color developer identified above) is also suitable in developing color print papers. Also, diethyl-para-phenylene-diamine hydrochloride or a color developing chemical sold commercially as AGFA AC-60 may be used as the developing agent with some papers, either alone or in combination with CD.

Following are four examples of suitable activator solutions for Type A color print papers, these examples illustrating suitable combinations of ingredients and illustrating the relative ratios of the ingredients: Example I "Carbo-Wax" OS-200 Benzyl alcohol Sodium metabisulfite CD Acetic acid (99%) Water in sufficient quantity to provide a pH of about 10.20 for a developing bath formed by mixing this Example with a selected common solution Example II Diethylene glycol Benzyl alcohol CD Water in sufficient quantity to provide a pH of about 10.20 for a developing bath formed by mixing this Example with a selected common solution Example III CD 5.00 gm Citric acid 2.00 gm Potassium ferrocyanide 0.25 gm Water in sufficient quantity to provide a pH of about 10.50 for a developing bath formed by mixing this Example with a selected common solution Example IV Diethyl-para-phenylene- diamine hydrochloride 3.00 gm "AC-60" 3.00 gm Sodium metabisulfate 0.40 gm Water in sufficient quantity to provide a pH of about.11.80 for a developing bath formed by mixing this Example with a selected common solution Following are four examples of suitable activator solutions for Type B color print papers, these examples illustrating suitable combinations of ingredients and illustrating the relative ratios of the ingredients: Sodium metabisulfite Diethyl-para-phenylene- diamine hydrochloride "AC-60" Water in sufficient quantity to provide a pH of about 11.10 for a developing bath formed by mixing this Example with a selected common solution Example II "AC-60" Diethyl-para-phenylene- diamine hydrochloride Water in sufficient quantity to provide a pH of about 11.40 for a developing bath formed by mixing this Example with a selected common solution Example III "AC-60" 7.00 gm Potassium metabisulfite 0.50 gm Water in sufficient quantity to provide a pH of about 11.70 for a developing bath formed by mixing this Example with a selected common solution Example IV Diethyl-para-phenylene diamine hydrochloride 4.00 gm "AC-60M 2.00 gm Sodium metabisulfite 0.40 gm Water in sufficient quantity to provide a pH of about 11.75 for a developing bath formed by mixing this Example with a selected common solution In processing color negative film, after the film has been subjected to the developing bath, the film is transferred to a stop-fix bath which, in general, stops the action of the developing fluid and initiates fixing of the emulsion and the image developed therein. The stop-fix bath includes a fixing ingredient such as sodium thiosulfate or ammonium thiosulfate which initiates dissolving of the unexposed and undeveloped silver halide. Sodium metabisulfite is included as a pH control and to extend the life of the fixing bath. Buffers such as acetic acid and boric acid are preferably included to stabilize the bath against changes in pH. Hardening agents such as potassium aluminate, sodium acetate, and thiosemicarbizide reduce the swelling of the gelatin and hardens it. Potassium iodide may be included in the solution to further restrain excessive coupling of the yellow color couplers.

Following are four examples of suitable stop-fix baths, these examples illustrating suitable combinations of ingredients and illustrating the relative ratios of the ingredients: Example I Sodium thiosulfate Sodium sulfite Acetic acid (99%) Boric acid Potassium aluminate Sodium acetate Water in sufficient quantity to provide the bath with a pH of about Example II Ammonium thiosulfate (60% solution) Sodium sulfite Acetic acid Boric acid Potassium aluminate Water in sufficient quantity to provide the bath with a pK of about Ammonium thiosulfato (60% solution) Sodium sulfite Acetic acid Boric acid Potassium aluminate Thiosemicarbizide Potassium iodide Water in sufficient quantity to provide the bath with a pH of about \ Example IV Sodium thiosulfate Sodium sulfite Acetic acid Boric acid Potassium aluminate Water in sufficient quantity to provide the bath with a pH of about In accordance with one aspect of the invention, a combined bleach-fix bath is provided which is effective both to bleach and to fix the emulsions on color negative films and on Type A and Type B papers. As is brought out elsewhere herein, the ingredients of this bleach-fix bath and the pH of the bath are so chosen and controlled that in processing color print papers, the papers are transferred directly from the developing bath to the bleach-fi bath without intermediate washing. Similarly, color nega-tive films are transferred directly from the stop-fix solution to the bleach-fix solution without intermediate washing.

The bleach-fix bath contains ingredients such as sodium hydroxide and trisodium phosphate which induce swelling of the gelatin to enable the bleaching and fixing agents to penetrate the gelatin and act upon constituents in the emulsion. These ingredients also facilitate control of the pH of the bath. The preferred fixing agent is ammonium thiosulfate, and the preferred bleaching agent is monosodium ferric EDTA. Preferably, sodium sulfite is included in the bath to lengthen the life of the fixing agent and to control unwanted stain (predominantly cyan) in the light or white areas of the completely processed emulsion. Potassium iodide is also preferably included to accelerate and complete the bleaching process by causing complete oxidation of metallic silver in the emulsion. A clarifying agent such as disodium Following are two examples of suitable bleach-fix baths, these examples illustrating suitable combinations of ingredients and illustrating the relative ratios of the ingredients: Example I Trisodium phosphate 12.75 gm Sodium sulfite 5.00 gm Monosodium ferric EDTA 23.40 gm Disodiura iEDTA dihydrate 8.10 gm Potassium iodide 1.35 gm Ammonium thiosulfate (60% solution) 105.00 cc Sodium metabisulfite 16.00 gm Water in sufficient quantity to provide the bath with a pH in the range from about 6.80 to about 7.00 Example II The ingredients set forth in bleach-fix bath of Example I plus: Sodium hydroxide 2.28 gm the amount of water being adjusted to provide the bath with a pH in the range of from about 6.80 to about 7.00 After a color negative film or a color print paper has been subjected to the bleach-fix bath, it is then washed, this being the only washing step in processing either the film or paper. Thereafter, it is subjected to a stabilizer solution which hardens the gelatin to prevent its being scratched during and after drying and which stabilizes the color image when it is subsequently exposed to light. The stabilizer solution preferably contains a wetting agent such as Eastman Kodak "Photo Flo 200" or "Photo Flo 600" to faci-litate smooth drying, i.e., without droplets. The stabilizer may also contain buffers such as sodium phosphate to help stabilize the solution against changes in pH. Also, in the color print paper stabilizer solution, an optical whitening agent such as DuPont Paper Whitener (SP) is provided along with an ingredient such as disodium EDTA dihydrate to prevent salts in the water from clouding or forming sludges.

A moisture retaining agent such as ethylene glycol may also be included to prevent the color print from curling and cracking where the print is dried under unusually dry condi-tions or under heat.

Following are three examples of suitable color negative film stabilizer baths, these examples illustrating suitable combinations of ingredients and illustrating the relative ratios of the ingredients: Example I Formaldehyde (40% solution) 20.00 cc "Photo Flo 200" 2.00 cc Water to provide said stabilizer solution with a ph of about 7.20 Example II Formaldehyde (40% solution) 30.00 cc "Photo Flo 600" 2.00 cc Water to provide said stabilizer solutio with a pH of about 7.00 Example III Formaldehyde (40% solution) 10.00 cc "Photo Flo 200" 2.00 cc Water to provide said stabilizer solution with a pH of about 7.30 Following are two examples of suitable stabilizer solutions for color print papers, these examples illustrating suitable combinations of ingredients and illustrating the relative ratios of the ingredients: Example I Disodium EDTA dihydrate 2.00 gm Sodium phosphate (monobasic) 5.50 gm Sodium phosphate (dibasic) 1.50 gm DuPont Paper hitener (SP) 2.00 cc Formaldehyde (40% solution) 10.00 cc Water to provide said stabilizer solution with a pH of about 7.00 Example II Disodium EDTA dihydrate 3.00 gm Sodium phosphate (monobasic) 7.50 gm Sodium phosphate (dibasic) 1.50 gm DuPont Paper Whitener (SP) 2.00 cc Formaldehyde (40% solution) 10.00 cc Ethylene glycol 2.00 cc Water to provide said stabilizer solution with a pH of about 8.50 After the color negative film or color print paper has been stabilized in the appropriate stabilizer solution, it is then dried in a conventional manner to complete the emulsion processing procedure.

The relative ratios of the ingredients cot forth in the various examples contemplate the use of laboratory reagent grade chemicals. However, the chemicals produced for commercial use vary somewhat in an unpredictable man- ner from laboratory grade reagent chemicals, and different commercially made batches of the same chemical also differ from each othe to a different extent. Therefore, in preparation of the various baths and solutions, a certain amount of adjusting of the relative ratios of the ingredients may be necessary to provide the baths and solutions with the proper pH. Such adjustment is accomplished in accordance with procedures well known in the art. In a number of the claims involving formulations, the term "substantially" is used in order to encompass such of these adjustments as may be necessary.

As was mentioned above, in commercial use, the emulsion-developing bath is preferably broken up into a common solution and separate activator solutions. This provides the various solutions with a long shelf life.

For the same purpose, the bleach-fix solution may be broken down into two separate solutions, one of which (part 1) contains the ammonium thiosulf te, the sodium metabisulfite and, where used, the sodium hydroxide ingredients. The other solution (part 2) contains the remaining ingredients listed in the examples. Sufficient water is provided in each solution to maintain the ingredients in dissolved condition.

The common developer solution and the three activator solutions, and parts 1 and 2 of the bleach-fix solution may contain, respectively, sufficient water so that when they are intermixed the correct pH is provided. Alter-natively, these solutions may initially be provided in concentrated form. In this situation, a selected activator solution is intermixed with the common developer solution and a predetermined quantity of water to provide a developing bath of the proper pH. Similarly, parts 1 and 2 of the bleach-fix solution are intermixed with a predetermined quantity of water to provide a bleach-fix bath having a pH in the range indicated.

In like manner, the stop-fix solution and the stabilizer solutions for negative film and print paper may be provided either as working solutions having their respectively correct pH values or in the form of concentrated solutions which, when mixed respectively with predetermined quantities of water, are provided with their correct pH values.

By way of example, the various Example I solutions set forth above can be provided in concentrated form by limiting their added water content to the following relative quanties, and in such concentrated form their respective pH will be as follows: Common developer solution 37.50 cc water pH 13.50 + 0.05 Activator solution, negative film 87.50 cc water pH 1.60 + 0.25 Activator solution. Type A paper 31.22 cc water pH 1.50 ± 0.20 Activator solution, Type B paper 50.00 cc water pH 2.40 i 0.15 Stop-fix solution 262.17 cc water pH 4.10 ± 0.10 Part 1 bleach-fix bath 6.25 cc water pH 6.20 ± .10 Part 2 bleach-fix bath 87.50 cc water pH 7.50 + 0.10 Negative film stabilizer solution 87.50 cc water pH 3.5 i 0.5 Color print paper stabilizer solution 50.00 cc water pH 5.5 '* 0.5 I have discovered that certain dyes can be added to various of the solutions for visual color identification without affecting in any way the color images developed in the color negative film or color print papers. Such dyes need only be chemically inert with respect to the other ingredients in the solution.

Examples of suitable dyes are food dyes such as those sold as "off-the-shelf" items in grocery stores such as the Kroger chain or by food specialty houses such as McCormick. These dyes serve suitably as visual color identifiers when added to the above example solutions in amounts ranging, for example, from about .3 cc to about .6 cc and in such quantities have no significant effect on the pH of the solutions.

By way of example, in color developing kits about to be sold as of the filing date of this application, identifying dyes are added to various of the solutions in the kit as follows: Type A Paper Actuator - Green Type B Paper Actuator - Blue Negative Film Actuator - Red Stop-Fix Solution - Yellow Paper Stabilizer Solution - Orange Film Stabilizer Solution - Violet These identifiers simplify the developing process for amateur and commercial processor alike and help guard against incorrect selection of a solution with consequent destruction or damage to an emulsion. Nevertheless, the dyes have no effect whatsoever on the finished product.

In general, any of the color negative film and color print paper activator solutions set forth in the above examples can "be used in combination with any of the common developer solutions set forth in the above examples and color images will be produced. The best results have been obtained utili ing Example I of each of the activator solutions in combination with Example I of the common solution. Similarly, while any of the alternate stop-fix and stabilizer solu-tions result in satisfactory color images, best results have been obtained with Example I of each. Slightly better results have been obtained with Example II of the bleach-fix bath than with Example I.

As was brought out above, by accurately propor-tioning the ingredients of the various solutions - particularly those of the common developing solution, the activator solutions, and the bleach-fix solutions - and by accurately controlling the pH thereof, two or more washing steps are eliminated. Moreover, the chemical energy of these solutions is greater than that of conventional solutions so that they perform their functions in general more quickly than do conventional solutions. The result is that the overall time required for processing an emulsion utilizing equipment and the method of this invention is two to five times as fast as the overall processing time in accordance with conventional equipment and processes. Nevertheless, the quality of the color image in the processed negative film or color print paper is in all cases as good and frequently better than in those processed in a conventional manner.

*- The simplified procedure facilitated by this invention enables the amateur to process both color negatives and color print papers with home equipment. Moreover, color print paper has actually been processed in conventional ccm-mercial black and white processing apparatus, namely, Pako 24-3C apparatus, product of Pako Corporation, Minneapolis, Minnesota. Color print paper can also be processed in Eastman Kodak Co. black and white processing apparatus Versa-mat Model 11.

In addition to the several advantages of the invention mentioned above, the solutions provided have a use life (in addition to shelf life) which compares favorably with conventional solutions. The color images produced have good color stability and the staining of white or light areas is minimal. The various solutions are easily mixed, and they can be used over a relatively wide range of temperatures normally regarded as room temperature. Perhaps more importantly, in the light of present knowledge, it appears highly probable that as new color negative films and color print papers are marketed, the fundamental formulations set forth above will be relatively easily adaptable for processing them by adjusting their present ingredients ¾nd by the use of other additives.

Claims (3)

What we claim is:-

1. A method of developing colour images in exposed photographic silver halide emulsions on colour .print paper which comprises contacting the emulsions with a colour ' ' developing solution having a pH in the range from 10.2 to 11.8 and without intermediate washing, transferring the emulsion to a bleach-fix solution having a pH in the range from 6.8 to 7·0 wherein said bleach-fix solution comprises the following ingredients in substantially the following relative ratios in aqueous solution: trisodium phosphate, 12.75 gm; sodium .sulfite, 5·00 monosodium ferric J3DTA, 3.40 gm; d'isodiumί EDTA dihydrate, 8.10 gm; potassium iodide, 1-55 S * ammonium thiosulfate (60% solution), 105.00 cc; sodium metabisulfite, 16.00 gm; water in sufficient quantity to provide said solution with a pH in said range, washing the emulsions after removing them from the bleach-fix solution, and transferring the emulsions to a dye-image stabilizer solution. , '

2. A method as claimed in claim 1 wherein said bleach-fix solution also contains sodium hydroxide in an amount of up to about 2.28 gm. 5. A method as claimed in claim 1 or 2 wherein said colour developing solution comprises the following ingredients in substantially the following relative ratios in aqueous solution: sodium hydroxide, 8.4-0 gm; hydroxyethyl ethylenedi-amine triacotic acid, 3.00 gm; borax, 27. 0 gm} sodium sulfite, -2.09 gm; potassium bromide, 0.72 gm; hydroxylamine sulfate, 1.20 gm; potassium hydroxide 4-.50 gm; polyethyleneglycols and me hoxypolyethylene glycols ranging in molecular weight. ( from 200 to 20 ,000 , 12.75 cc; benzyl alcohol, 12.75 cc; sodium metabisulfite, 0.50 gm; CD (as hereinbefore defined), 5.00 gm; acetic acid (99%) i 3.50 cc; water to provide said developing solution with a pH of 10.2. 4. A method as claimed in claim 1 or 2 wherein said colour developing solution comprises the following ingredients in substantially the following relative ratios in aqueous solution: sodium hydroxide, 8.40 gm; hydroxyethyl ethylenedi- amine triacetic acid, 3·00 gm; borax 27. 0 gm; sodium sulfite, 2.09 gm; potassium bromide, 0. ?2 gm; hydroxylamine sulfate, 1.20 gm; potassium hydroxide 4.50 gm; diethylene glycol, . 25.00 cc; benzyl alcohol, 25.00, cc; CD (as hereinbefore defined) 8.00 gm; water to provide said developing solution with a pH of 10.2. 5· A method as claimed in claim 1 or 2 wherein* said colour developing solution comprises the following ingredients in substantially the following relative ratios in aqueous solution: sodium hydroxide, 8.40 gm; hydroxyethyl ethylenedi- amine triacetic acid, 3· 00 gm; borax, 27.50 gm; sodium sulfite, 2.09 gm; potassium bromide, 0. 2 gm; hydroxylamire sulfate , 1.20 gm; potassium hydroxide 4.50 gm; CD, (as hereinbefore defined) 5»00 gm; citric acid, 2.00 gm; potassium ferrocyanide , Ο.25 gm; water to provide said developing solution with a pH of IO.5. 32940-2 6. A method as claimed in claim 1 or 2 wherein said -colour developing solution comprises the following ingredients in substantially the following relative ratios in aqueous solution; sodium hydroxide, 8.40 gm; , hydroxyethyl ethylenedi- amine triacetic acid, 3.00 gm; borax, 2 .50 gm; .sodium sulfite 2.09 gm; potassium bromide, 0.72 gm; hydroxylamine sulfate, 1»20 gm; potassium hydroxide 4.50 gm; diethyl-para-phenylene- diamine-hydrochloride , 3.00 gm; 4-(N-omega-sulpho-n-butyl-N- n-butylamino)-aniline, 3·00 gm; sodium bisulfite , 0.40 gm; water to provide said developing' solution with a pH of 11.8. 7· A method as claimed in claim 1 or 2 wherein said developing solution comprises the following ingredients in ■substantially the following relative ratios in aqueous solution: sodium hydroxide, 8.40 gm; hydroxyethyl ethylene- diamine triacetic acid, 3.00 gm; borax, 2 .50 gm; sodium sulfite, 2.09 gm; potassium bromide, 0.72 gm; hydroxylamine sulfate, 1.20 gm; potassium hydroxide, 4.50 gm; sodium metabisulfite, 0.40 gm; diethyl-para-phenylene-diamine hydrochloride, 5.00 gm; 4-(N-omega-sulpho-n-butyl-N-n- butylamino)-aniline , 1.00 gm; water to provide said developing solution with a pH of 11.1. 8. A method as claimed in claim 1 or 2 wherein said developing solution comprises the. following; ingredients in substantially the following relative ratios in aqueous solution: sodium hydroxide, 8.40 gm; hydroxyethyl ethylene- diamine triacetic acid, 3.00 gm; borax 27· 50 gm; sodium sulfite, 2.09 Sm5 potassiun bromide, 0.72 gmj hydroxylamine 32940-2 sulfate, 1.20 gm; potassium hydroxide, .50 gra; diethyl-para-phenylene-diamine hydrochloride, 2.00 gm; 4-(N-omega-sulpho-n-butyl-N-n-butyl-araino)-aniline 6.00 gm water to provide said developing solution with a pH of 11.4. 9. A method as claimed in claim 1 or 2 wherein said developing solution comprises the following ingredients in substantially the following relative ratios in aqueous solution: sodium hydroxide, 8.40 gm; hydroxyethyl ethylene-diamine triacetic acid, 3.00 gm; borax 27.50 gm; sodium sulfite, 2.09 gm; potassium bromide, 0.72 gm; hydroxylamine sulfate, 1.20 gm; potassium hydroxide, 4.5Q gm; 4-(N-omega^ sulpho-n-butyl-N-n-butylainino)-aniline » 7.00 gm potassium metabisulfite , 0. 50 gm; water to provide said developin solution with a pH of 11.7· 10. A method as claimed in claim 1 or 2 wherein said colour developing solution comprises the following ingredients in substantially the following relative ratios: EDTA, 4.00 gm; sequestering or chelating agent, 4.00 gm; sodium sulfite, 4.00 gm; sodium hydroxide, 1.30 gm; trisodium phosphate, 50.00 gm; potassium bromide, 2.00 gm; wetting agent, 1.25 cc; 4-(N-omega-sulpho-n-butyl-N-n-butylamino)-aniline , 6.00 gm; diethyl-para-phenylene-diamine hydrochloride, 2.00 gm; water to provide said developing solution with a pH of 11.4. 11. A method as claimed in claim 1 or 2 wherein said developing solution comprises the following ingredients in substantially the following relative ratios: EDTA, 4.00 gm; sequestering or chelating agent, 4- .00gm; sodium sulfite, 4-, 00 gm; sodium hydroxide, 1 .30 gm; trisodium phosphate, 50.00 gm; potassium bromide, 2.00 gm; wetting agent, 1 .25 cc; diethylene glycol, 25.00 cc; benzyl alcohol, 25.00 cc; CD (as hereibefore defined) 8.00 gm; water to provide said developing'' solution with a pH of 10.2. 12. A method as claimed in claim 1 or 2 wherein said colour developing solution comprises the following ingredients in substantially the following relative ratios: sodium hydroxide, 8.75 gm; borax, 27.50 gm; sodiumr sulfite , 2.08 gm; potassium bromide, 0.72 gm; sodium chloride,' 0.73 gm; hydroxylamine hydrochloride, 1 .20 gm; sequestering or chelating agent, 3 ·00 gm; -(N-omega-sulpho-n-butyl-IT-n-butylamino)-aniline , 7· 00 gm; potassium metabisulfite, 0 .50 S^; water to provide said- · developing solution wit a pH of 11 . · 13. . A method as claimed in claim 1 or 2 wherein said colour developing solution comprises the following ingredients in substantially the following relative ratios: sodium hydroxide, 8.75 gm; borax, 27.5 gm; sodium sulfite, 2.08 gm; potassium bromide, 0.72 gm; sodium chloride, 0.73 gm hydroxylamine hydrochloride, 1 .20 gm; sequestering or chelating agent, 3.OO gm; CD (as hereinbefore defined) 5·00 gm; citric acid, 2.00 gm; potassium ferrocyanide , 0.25 g¾; water to provide said developing solution with a pH of 10.5 · .14. A method as claimed in claim 1 or 2 wherein said colour developin solution comprises the following ingredients in substantially the following relative ratios: sodium hydroxide, 7 ·25 gm* borax, 27.50 gm; sodium sulfite, 2.00 gm; potassium bromide, 0.4-8 gm; sodium chloride, 0-.73 gm; hydroxyl-nm.i.no hydrocMorirl© , 1 .20 Rin ; noquoo erinn or chelating a^on , 2 *40 gm; potassium hydroxide, 4.50 gm; diethyl-pura-phenylenediamine hydrochloride, 3o00 gm; 4-(N-omega-sulpho-n-butyl-N-n-butylamino)-aniline, 3.00 gm; sodium bisulfite, 0.40 gm; water to provide said developing solution with a pH of 11.8. 15. A method as claimed in any one of the preceding claims wherein the dye image stabilizer solution comprises the following ingredients in substantially the following relative ratios: disodium EDTA dihydrate, 2.00 gm; sodium phosphate(monobasic) , 5* 50 gm; sodium phosphate (dibasic), 1.50 gm; optical whitening agent, 2.00 cc; formaldehyde (40,/' solution), 10.00 ce; water to provide said stabilizer solution with a pH of 7·0. 16. A method as claimed in any one of Claims 1 to 14 wherein the dye image stabilizer solution comprises the following ingredients in substantially the following relative ratios: disodium EDTA dihydrate, 3.00 gm; sodium phosphate (monobasic), 7.50 gm; sodium phosphate (dibasic), 1.50 gm; optical whitening agent, 2.00 cc; formaldehyde (40 solution), 10.00 cc; ethylene glycol, 2.00 cc; water to provide said stabilizer solution with a pH of 8.5· 17. A modification of the method according to Claim 1, for developing colour images in exposed photographic silver halide emulsions on negative colour film, which comprises contacting the emulsions with a colour developing solution having a pH in the range of from 10.2 to 11.8/ transferring the emulsions without washing to a stop-fix solution having a pH in the range of from 4.3 to 4.6 effective to stop the action of said colour developing solution; and, without intermediate washing, transferring the emulsions to a bleach-fix solution which has a pH in the range of from 6.8 to 7.0 and comprises the following ingredients in substantially the following relative ratios in aqueous solution: trisodium phosphate, 12.75 gm; sodium sulfite, 5.00 gm; monosodium ferric EDTA, 23-40 gm; disodium EDTA dihydrate, 8,10 gm; potassium iodide, 1.35 gm» ammonium thiosulfate (60 solution), 105.00 cc; sodium raetabisulflte, 16.00 gm; water in sufficient quantity to provide said solution with a pH in said range; washing the emulsions after removing them from the bleach-fix solution, and transferring them to a dye image stabilizer solution. 18. A method as claimed in Claim 17 wherein the bleach-fix solution also c ntains sodium hydroxide in an amount of up to about 2,28 gm, 19. A method as claimed in Claim 17 or 18 wherein the stop-fix solution comprises the following ingredients in substantially the following relative ratios: sodium thiosulfate, 100,00 gm; sodium sulfite, 15.00 gm; acetic acid (99#)> 18.00 cc; boric acid, 7.50 gm; potassium aluminate, 10,00 gm; sodium acetate, 2.50 gm; water to provide said stop-fix solution with a pH of 4.3· 20. A method as claimed in Claim 17 or 18 wherein the stop-fix solution comprises the following ingredients in substantially the following relative ratios: ammonium thiosulfate (60 solution), 105.00 cc; sodium sulfite, 15.00 gm: acetic acid, 13.40 gm; boric aeid 7.50 gm; potassium aluminate, 10.00 gm; water to provide said said, stop-fix solution comprises the following ingredients * in substantially the following relative ratios ammonium thiosulfate (6.0?ά solution), 105.00 cc; sodium sulfite; 15.ΟΟ gm; acetic acid, 13.4-0 gm; boric acid; 7 · 50 gm; potassium aluminate, 2.50 gm; thiosemicarb zide , 2.00 gm; potassium iodide, 0.50 gm; water to provide said stop-fix solution with a pH of 4.6. 22. A method as claimed in claim 7 or 18 wherein said stop-fix solution comprises the following ingredients in substantially the following relative ratios: sodium thiosulfate, (60¾ solution), 200.00 gm; sodium sulfite, 15.00 gm; acetic acid, 15. -0 gm; boric acid, 7· 0 gm; potassium aluminate, 2.50 gm; water to provide said stop-fix solution with a.pH of , . ...... 25. A method as claimed in any one of claims 17 to 22 wherein said developing solution comprises the following ingredients in substantially the following ratios in aqueous solution: sodium hyrdroxide , 8.4-0 gm; hydroxyethyl ethylenedia ine triacetic acid, 5.00 gm; borax, 27. 0 gm; sodium sulfite, 2.09 gni; potassium bromide, 0.72 gm; hydroxylamine sulfate, 1 .20 gm; potassium hydroxide, 4- .50 gm; acetic acid (9¾¾) > 1.60 cc; polyethylene glycols and methoxy polyethylene glycols ranging in molecular weight from 200 to 20 ,000 , 6.00 cc; benzyl alcohol, 5.25 oc; sodium metabisulfite , 0.50 gm; CD (as hereinbefore defined) 5.25 gm; potassium iodide (0, ?£ solution) , 5.50 cc; potassium bromide, 1 .09 gm; water to provide said developing solution with a pH of 10.7 ; 24. A method as claimed in any one of claims 17 to 22 wherei said developing solution comprises the following ingredients in substantially the following ratios in aqueous solution: sodium hydroxide, 8.40 gm; hydroxyethyl ethylenediamj.ne triacetic acid, 3 ·00 gn; borax, 27.50 gin; sodium sulfite, 2.09 gci; . potassium bromide, 0.72 gm; hydroxylamine sulfate, 1 .20 gm; potassium hydroxide, .50 gm; diethylene gylcol, 4.00 cc; benzyl alcohol, 4.00 cc; CD (as hereinbefore defined) 5·00 gm; v/ater to provide said developing solution with a pH of 10.75· · A method as claimed in any one of claims 17 to 22 wherein said developing solution comprises the following ingredients in substantially the following ratios in aqueous soltuion: sodium hydroxide, 8.40 gm; hydroxyethyl ethylenediamine triacetic acid, 3 · 00 gm; borax, 27.50 gm; sodium sulfite, 2.09 gn; potassium bromide, 0.72 gm; hydroxylamine sulfate, 1 .20 gm; potassium hydroxide, 4.50 gm; CD (as hereinbefore defined) 5 ·00 citric acid, 1 .30 cc; potassium bromide, 1 .00 gm; water to provide said developing solution with a pH of 10.75· 26. A method as claimed in any one of claims 17 to 22 wherein said developing solution comprises the following ingredients in substantially the following ratios in aqueous solution: sodium hydroxide, 8.40 gm; hydroxyethyl ethylenediamine triacetic acid, 3 · 00 gm; borax, 27.50'gm; sodium sulfite, 2.09 gm; potassium bromide, 0.72 gm; hydroxylamine sulfate, 1 .20 gm; potassium hydroxide, . 0 gm; polyethylene glycols and methoxy polyethylene glycols ranging in molecular weight from 200 to 20,000 ,, ·25 cc; benzyl alcohol, 5·25 cc; CD (as hereinbefore defined) ·25 m; potassium bromide, 1.08 gm; potassium iodide, (0.01^ solution) 5 · 30 cc; wetting, agent 1 .00cc ; sodium bisulphate sodium bisulfite 0.40 gm; 2.10 gm;/water to provide said developing solution with a pH of 10.77. 27. A method as claimed in any one of claims 17 to 22 wherein said colour developing solution comprises the following ingredients in substan ially the following relative ratios: EDTA 4.00 gin; sequestering or chelating agent, 4.00 gm; sodium sulfite, 4.00 gm; sodium hydroxide , 1 . 30 gm; trisodium phosphate, 50.00 gm potassium bromide, 2.00 go; wetting agent, 1 . 25 cc; diethylene glycol, 4.00 cc; benzyl alcohol, 4.00 cc; CD (as hereinbefore defined) « 00 gm; water to provide said developing solution with a pH of 10.75 · 28. A method as claimed' in any one of claims 17 to 22 wherein said colour developing solution comprises the following ingredients in substantially the . following relative ratios: DTA, 4.00 gm; sequestering or chelating agent, 4.00 gm; sodium sulfite, 4.00 gm; sodium hydroxide, 1.30 gm; trisodium phosphate, 50.00 gm potassium bromide, 3· 09 gm; wetting agent, 1 . 25 cc; acetic acid (99fj) » - .60 cc ; polyethylene'»glycols and methoxy polyethylene glycols ranging in molecular weight from 200 to 20 , 000 , 6.00 cc ; benzyl alcohol, 5.25 cc; sodium otabisulfite, 0.50 gm; CD (as hereinbefore defined) 5 · 25 gm; potassium iodide (0.1?' solution), 5.30 cc; water, to provide said developing solution with a pH of 10.7. 29. A method as claimed in any one of claims 17 to 22 wherein said colour developing solution comprises the following ingredients in substantially the following relative ratios; sodium' hydroxide, 8.75 gm; borax, 27.50 gm; sodium sulfite, 2,08 gm; . potassium bromide, 1 .72 gm; sodium chloride, 0.73 ¾"m; hydroxylamine hydroc loride, 3 040 1.20 gm; sequestering or chelating agent, 5.00 gm; CD (as hereinbefore defined) 5.00 gm; citric acid, 1.50 gm;, water to provide said developin solution with a-'pH of 10.75· 50. ( '. A. method as claimed in any one of claims to 22 wherein said developing solutio comprises substantially the following ingredients i substantially" the following relative ratios: sodium hydroxide, 8,75 gm; borax, 27.50 gm; sodium sulfite, 2.08 gm; potassium bromide, 1.81 gm; sodium chloride, Ο.75 gin; hydroxyiamine hydrochloride, 1.20 gm; sequ-estering or chelating agent, 5· 00 gm; acetic acid (99i¾) , 1.60 cc ^"polyethylene glycols and methoxy polyethylene glycols ranging in molecular weight from 200 to 20,000, 6.00 cc; benzyl alcohol, 5· 25 cc ; sodium netabisulfite , 0.50 gm; CD (as hereinbefore defined) 5.· 25 gm; potassium iodide (0.1Γί solution), 5·50 cc; water to provide said developing solubion with a pll of 10.7. ' ' 1. A method as claimed in any one of claims 7 to 22 wherein said colour developing solution comprises the following in¾redients in substantially the following relative ratios: sodium hydroxide, « 25 Sia; borax, 7. 0 gm; sodium sulfite, 2.00 gm; potassium bromide, 1.57. Sm» sodium chloride, 0.75 Gm> hydroxyiamine hydrochloride, 1.20 gm; sequestering or chelating agent, 2.4-0 gm; potassium hydroxide, 4-.50 gm; acetic acid (99;5) > 1.60 cc; polyethylene glycols and' methoxy polyethylene glycol ranging in molecular weight from 200 to 20 ,000 , 6.00 cc; benzyl alcohol, 5 « 25 cc; sodium metabisulfite, 0.50 gm; •CD (as hereinbefore defined) 5 « 5 gm; potassium iodide, (0.1>ί solution), 5· 30 cc; water to provide said developing solution with a pH of 10.7 · 32. A method as claimed in any one of claims 17 to 22 wherein said colour developing solution comprises the following ingredients in substantially the following relative ratios: sodiun hydroxide, 7 · 25 εω; borax, 27 · 50 gm; sodium sulfite ,.2.00 gm; potassium bromide, .56 gm; sodium chloride, 0.73 sm ; hydroxy!amine hydrochloride, 1 .20 gm; sequestering or chelating agent, 2.40 gm; methoxy polyethylene glycols ranging in molecular weight from 200 to 20 ,000 , .25 cc, benzyl alcohol, 5.25 cc; CD (as hereinbefore defined) 5 · 2 gm; potassium iodide (0.01?≤ solution), 5 · 30 cc; wetting agent, 1 .00 cc sodium bisulfite, 0.4-0 gm; sodium bisulfate, 2.10 gm; water to provide said developing solution wi'th a pH of 10.7 . 33· A method as claimed in any one of claims 17 to 32 wherein said dye image stabilizer solution compris the following ingredients in substantially the following relative ratios: formaldehyde (4Ό?ί solution), 20.00 cc; wetting agent, 2.00 cc; water to provide said stabilizer solution with a pH of 7.2.

3. . A method as claimed in any one of claims 1 to 32 wherein said dye image stabilizer solution -2 comprises substantially the following ingredients in substantially the following relative ratios: formaldehyde (4-0?-> solution), 30.00 cc; wetting agent, 2.00 cc; water to provide said stabilizer solution with a pH of 7.0. 35 · Λ method as claimed iri any one of claims 1 to 32 wherein said dye image stabilizer solution comprises substantially the follov/ing ingredients in substantially the follov/ing relative ratios: formaldehyde (4-O.'. solution), 10.00 cc; wettin agent, 2.00 cc; water to provide said developing solution with a pH of 7· 3 · $6. A method of developing colour images in •exposed photographic emulsions as clained- in claim 1 ■ -· - — or 17 substantially as hereinbefore described with reference , o and as illustrated in the foregoing examples. For Ihe Applicants DR. RciHHOLD COHN AND PARTNERS B y