US2575182A - Photographic silver halide emulsions and developers containing 5-acyloxypyrazole color formers - Google Patents

Description

Patented Nov. 13, 1951 PHOTOGRAPHIC SILVER HALIDE EMUL- SIONS AND DEVELOPERS CONTAINING -ACYLOXYPYRAZOLE COLOR FORMERS Elmore Louis Martin, Wilmington, Dcl., assignor to E. I. du Pont de Nemours & Company, Wilmington, DeL, a corporation of Delaware No Drawing. Application August 21, 1946, Serial No. 692,143

8 Claims.

Thi invention relates to processes of color photography and to developer solutions and photographic emulsion layers therefor, utilizing fi-acyloxypyrazoles which have an unsubstituted hydrogen atom attached to a carbon atom in the 4-position of the pyrazole ring.

Some 5-acyloxypyrazoles have been desscribed in the chemical literature. Various procedures for preparing them are referred to in Handbuch fiir Organischen Chemie, Beilstein Prager- Jacobsen, vol. XXIV. Tw recent literature articles disclosing such compounds are in the Journal of the American Chemical Society, vol. 65, pages 1495 to 1502, and vol. 66, pages 1851 to 1855. The latter articles, while teaching the utility of various other pyrazole derivatives for color coupling development processes of forming photographic dye images, imply that the 5- acyloxpyrazoles disclosed are unsuitable for such uses.

An object of thi invention is to provide processes of forming photographic dye images utilizing 5-acyloxypyrazoles. A further object is to provide processes for the color coupling development of silver halide images utilizing S-acyloxypyrazoles which have an unsubstituted hydrogen atom attached to the carbon atom in the 4-position of the pyrazole' ring. A further object is to provide practical methods of incorporating such compounds int photographic developer solutions and water-permeable colloid coating solutions. Still other objects will be apparent from the following description of the invention.

It has been established that photographic dye images can be produced by developing exposed or reducible silver halide images in the presence -of a 5-acyloxypyrazole having an unsubstituted hydrogen atom attached to the carbon atom in the 4-position of the pyrazole ring. This may be accomplished by incorporating the said compounds with a photographic developer solution containing a primary, aromatic, amino, color developing agent or by incorporating the said compounds in a hydrophilic colloid-silver halide emulsion layer or in a hydrophilic colloid layer which is in operative contact with such an emulsion layer.

The 5-acyloxypyrazoles in question may be advantageously incorporated with the developer solutions by dissolving them in a water-miscible, organic solvent or a mixture of water and such a solvent and admixing the resulting solution with the aqueous developer solution. Another practical method consists of bringing the aforesaid compounds into aqueous solution by means of a hydrotropic agent and admixing the solution With the aqueous developer. Both the water-miscible organic solvent and a hydrotropic agent can be used if desired.

Water-permeable colloid layers including those which contain light-sensitive silver halides can be made by admixing the aqueous solution of the colloid with a solution containing the 5-acyloxypyrazole having an unsubstituted hydrogen atom attached to the carbon atom in the 4-position of the pyrazole ring described in the preceding paragraph. Thus they may be added to a gelatinosilver halide emulsion which is then coated onto a suitable support and dried.

In the case of the 5-acyloxypyrazoles which contain a solubilizing' group, e. g., a free carboxylic acid group or sulfonic acid group or a water-soluble salt thereof, e. g., alkali metal including sodium, potassium, ammonium, diethylamine, diethylcyclohexylamine, etc., it is not necessary to use water-miscible solvents or hydrotropic agents.

The 1- and 3-positions of the 5-acyloxypyrazoles may be substituted by various groups or radicals which do not interfere with color coupling development reactions. Thus they may contain aryl, alkyl, aralkyl, cycloaliphatic or heterocyclic radicals which have one or more hydrogen atoms thereof substituted by various groups, e. g., halogen including chlorine and bromine, sulfonic acid, carboxylic acid and their water-soluble salts, amide, nitro, alkoxy, aryloxy, etc.

A group of such 5-acyloxypyrazoles well-suited for use in the photographic processes and compositions in question maybe represented by the formula wherein Y is a member taken from the group consisting of carbonyl CO) and sulfonyl (-SO2.) radicals, Z-Y is an acyl radical, R is an aryl or substituted aryl radical or a heterocyclic radical joined to the N atom of the pyrazole ring through a carbon atom, and R is a monovalent hydrocarbon nucleus or the same If it is desired to introduce selected substituents into the R. or R groups, this may be accomplished prior to or after either of the steps by the normal chemical manipulations. v

In the formula Z-Y may be the acyl radical corresponding to a carboxylic acid or a sulfonic acid of the formula ZYOI-I. Thus Z-Y may be,

the acyl radical of an aliphatic, aliphatic-aromatic, cycloaliphatic, aliphatic, aromatic or heterocyclic carboxylic or sulfonic acid, e. g. formyl,

acetyl, methoxyacetyl, beta-carboxypropionyl, chloracetyl, carbethoxy, caproyl, stearoyl --OC--(CH2)1|.CHO

OCHz oo-(cm),.cnl

CH2 -OC(CH2) n-COOCH3, benzoyl, chlorobenzoyl,

nitrobenzoyl, toluenesulfonyl, butanesulfonyl, benzenesulfonyl, picolinoyl, nicotinoyl, isonicotinoyl, thienoyl, etc.

Suitable specific radicals for R include methyl, phenyl, naphthyl, carboxyphenyl, sulfophenyl, N substituted carbamylphenyl, N substituted sulfamylphenyl, chlorophenyl, nitrophenyl, aminophenyl, pyridyl, benzothiazolyl, carboxymethoxyphenyl, beta-sulfoethyl, beta-carboxyethyl, sulfo 2 chloro-phenyl, propanol 2 sulfonic acid-3, etc.

Suitable additional specific radicals for R include methyl, phenyl, ethyl, furyl, naphthyl, carboxyphenyl, nitrophenyl, chlorophenyl, carbethoxymethyl, methoxyphenyl, benzyl, and isopropyl. The 5-acy1oxypyrazole compounds set forth in copending applications Serial Number 667,125, filed May 3, 1946, now U. 5. Patent No. 2,476,987, and Serial Number 682,137, filed July 8, 1946, now U. S. Patent No. 2,476,988, including the various specific classes therein described are useful in the present invention.

A convenient and practical method for the preparation of S-acyloxypyrazoles comprises reacting a fi-pyrazolone having an active methylene group in the 4-position with at least one molecular equivalent of an acyl halide and an acid binding agent, e. g., an inorganic base such as sodium hydroxide, potassium hydroxide, and sodium carbonate, or an organic base, e. g., pyridine, piperidine, diethylcyclohexylamine, ethylenediamine, diethylamine, etc.

The following examples illustrate in greater detail the invention. The parts of reagents given in the examples are by weight. By the expression 5-acyloxypyrazole nucleus is meant the pyrazole ring system remaining after the removal of R and R in the general formula.

EXAMPLE I A suspension of five parts of 1-(4-carboxyphenyl)-3-methyl-5-pyrazolone in ten parts of acetic anhydride containing a trace of sodium acetate is heated gently until a homogeneous solution is obtained and then is refluxed gently for an additional period of fifteen minutes. The acetic acid and excess acetic anhydride are removed by distillation under reduced pressure on a steam bath. The 1- (l-carboxyphenyl) -3- methyl-S-pyrazolyl acetate formed'is dissolved in diethyl ether and three parts of thionyl chloride are added. A vigorous reaction occurs and sulfur dioxide and hydrogen chloride are evolved. The mixture is refluxed for fifteen minutes during which time the evolution of gases ceases. The ether is removed by evaporation and the resulting 1 (4-chloroformy1phenyl) -3-methyl 5 pyrazolyl acetate is added to a mixture of three parts of m-aminobenzaldehyde dimethyl acetal in a solution of three parts of potassium carbonate in thirty parts of water at 5 C. The mixture is shaken vigorously and after several minutes the m [p-(5-acetoxy-3-methyl 1 pyrazolyD- benzamidolbenzaldehyde dimethyl acetal is separated and washed first with water and then with ether. About one part of the reaction product is dissolved in 50 parts of alcohol and 50 parts of a developer solution of the following composition is added:

Developer solution Parts p-Aminodiethylaniline hydrochloride 2.0 Sodium carbonate, monohydrate 20.0 Sodium sulfite, anhydrous 2.0 Potassium bromide 0.5 Water to make 1000.0

A piece of film bearing a silver ferrocyanide image in a gelatin layer is developed in this photographic developer and after removal of the metallic silver by means of a bleach containing potassium ferricyanide and removal of the resulting ferrocyanide with sodium thiosulfate yields a clear, strong magenta dye image.

Development of a piece of film bearing a silver ferrocyanid-e image in a gelatin layer with a photographic developer comprising two parts of the above 1 (4 carboxyphenyl) 3 methyl- 5-pyrazolyl acetate and the above developer solution yields a clear, strong magenta dye image which is leached to a considerable extent by water due to the presence of the solubilizing carboxylic acid group.

EXAMPLE II Development of a piece of film bearing a silver .ferrocyanide image in a gelatin layer with a photographic developer comprising 1-phenyl-3- methyl-E-pyrazolyl methyl carbonate (see Himmelbauer, J. pr. (2) 54, 189 (1896)) and p-a-minodiethylaniline as described in Example I gives a strong magenta dye image after removal of the silver image.

EXAMPLE III Development of a piece of film bearing a silver ferrocyanide image in a gelatin layer with a solution of N-B-(5-methylcarbonato-3-methyl-l-pyrazolyl) phenyl methyl urethane,

Development of a piece of film bearing a silver ferrocyanide image in a gelatin layer with a solution of m [p ethylcarbonato-3-methyl-1- pyrazolyl) benzamidol benzaldehyde ethylene gly-. col acetal (see Example II of application Serial Number 667,125, filed May 3, 1945, for properties and preparation) in a p-aminodiethylaniline developer as described in Example I gives a strong magenta dye image having a maximum absorption of light of wavelength 535 m EXAMi EE v Development of a piece of film bearing a silver ferrocyanide image in a gelatin layer with a solution of m-[p-(5-benzoxy-3-methyl1-pyrazoly1) phenoxyacetamido] benzaldehyde ethylene glycol acetal (see Example III of application Serial Number 667,125, filed May 3, 1946, for preparation and properties) with p-aminodiethylaniline developer as described in Example I gives a strong magenta dye image.

EXAMPLE VI To ten parts of a polyvinyl acetal having a 5- ethyl-carbonatopyrazole nuclei content of approximately six per cent and prepared as described in Example VI of application Serial Number 682,137, filed July 8, 1946, now U. S. Patent No. 2,476,988, is added 60 parts of alcohol, 135 parts of water, and 0.8 part of potassium hydroxide solution. Solution is effected by warming to 70 C. for ten minutes with stirring. The essentially colorless 5% solution of the polyvinyl acetal is cooled to 40 C. and is used to prepare an emulsion under conditions which will not expose or cause fogging of the sensitive silver salt as follows: To 90 parts of the 5% magenta colorforming polyvinyl acetal solution is added 31 parts of 3 N ammonium bromide and two parts of 0.5 N potassium iodide. This solution is stirred at 50 C. while adding a solution of 29 parts of 3 N silver nitrate, 50 parts of water, and 15.3 parts of 28% ammonium hydroxide during one minute. After stirring for a total of one-half hour, 50-100 parts of a sodium sulfate solution is added. The precipitated silver halide/color-formeremulsion is washed for one hour in running water, after which the excess water is drained off. The remainder of the original solution, together with 35 parts of ethanol and 15 parts of water, is added and the mixture is stirred at 65 C. for one-half hour. After cooling to C., the emulsion is coated on a baryta sized white paper. The 'resulting paper is exposed to form a latent image, then developed in the developer solution given in Example I. The paper is then fixed in 25% sodium thiosulfate solution, Washed, bleached with 4% potassium ferricyanide, washedand fixed in 25% sodium thiosulfate. The resulting paper contains a bright, strong magenta dye image.

EXAMPLE VII A 5% solution is prepared from ten parts of a polyvinyl acetal containing 5-benzoxypyrazole nuclei prepared as described in Example V of application Serial Number 682,137, filed July 8'," 1946, now U. S. Patent No. 2,476,988, according to the procedure given in Example VI. Preparation of a silver halide emulsion containing such an acetal, coating on paper, and processing as described in Example III gives a strong magenta dye image.

6 EXAMPLE VIII Development of a piece of film bearing a silver ferrocyanideimage in a gelatin layer with a photographic developer comprising two parts of 1-(4-carboxyphenyl) -3-methyl 5 pyrazolyl ptoluenesulfonate and the developer described in Example I yields a clear, strong magenta dye image which is leached to a considerable extent by water due to the presence of the solubilizing carboxylic acid group. The 1-(4-carboxyphenyl) 3-methyl-5-pyrazolyl p-toluenesulfonate is prepared as follows: To a solution of 160 parts of potassium hydroxide in a mixture of 800 parts of water and 50 parts of dioxane is added 218 parts of 1-(4-carboxyphenyl)-3-methyl-5- pyrazolone. The resulting solution is cooled to 20 C. by means of external cooling and then to 5 C. by the addition of crushed ice directly to the reaction mixture. A solution of 225 parts of p-toluenesulfonyl chloride in 225 parts of anhydrous dioxane is added in one portion to the vigorously stirred solution. After being stirred at 23 C. for one hour, the solution is heated to 35 C. and acidified by the addition of 150 parts of 50% acetic acid. The crystalline product is collected, washed thoroughly with cold water and dried. I Crystallization of the dry product (five parts ethanol for each part of product) gives glistening, colorless needles melting at l85-187 C. in 80-90% yield. Analysis calculated for C18H16O5N2S:C=58.03;H=4.33; S=8.61. Found: 0:57.04, 51.31; H=4.71, 4.44; and S=8.31, 8.30.

EXAMPLE IX To a solution of 17 parts of 1-phenyl-3-methyl 5-pyrazolone in parts of pyridine cooled to 10 C. is added 15 parts of dichloroacetyl chloride, the temperature being maintained at 10 C. by external cooling and by controlling the rate of addition of the acid chloride. The resulting mixture is stirred for one hour at 10 C. and then for one half hour at 20 C. Chloroform is added to the mixture and the resulting mixture extracted first with water, then with dilute hydrochloric acid, then 5% sodium carbonate solution, and finally with water. Concentration of the chloroform layer yields an oil which cannot be induced to crystallize. Treatment of an alcoholic alkaline solution of the oil in the presence of p-aminodiethylaniline with aqueous potassium ferrocy-f anide gives a strong magenta dye. V

The ,5-acyloxypyrazoles may be incorporated into, the developer solution or may be incorporated into the photographic layer or a layer coactive therewith. The binding agent for the photographic layer may be gelatin or other colloidal material, such as collodion, partially hydrolyzed cellulose acetate, polyvinyl alcohol and its partially substituted esters and acetals, hydrolyzed vinyl ester/olefin interpolymers, hydrophilic polyamides, etc. The carrier for the photographic layer may be a transparent medium, such as glass, or a plastic material, e. g., cellulose derivative or synthetic resin or superpolymer, e. g., cellulose ester, polyvinyl acetals, polyamide, copolymers of selected fluorine substituted ethylenes, etc., or a non-transparent reflecting medium, such as paper or pigmented cellulose ester film. The 5-acyloxypyrazoles may be used with single layer coatings or may be used with a plurality of layers which may or may not contain other color-forming dye compounds.

Various dispersing agents may be used for incorporating the 5-acyloxypyrazoles into the photographic layer. Suitable such agents include long chain alkyl sulfates and sulfonates, e. g., sodium dodecyl sulfate and sodium chlorocetanesulfonate, non-ionic agents, e. g., mannitan monopalmitate and ethylene oxide/alkylated phenol condensates, the betaines, such as C-cetylbetaine, cation-active agents, such as cetyl pyridinium bromide, and the soaps.

In the case of multilayer photographic film or paper in which the -acyloxypyrazole is incorporated into one or more layers, it may be necessary to use special precautions to prevent wandering of the 5-acyloxypyrazoles from the sensitive layer in which it is incorporated. This may be accomplished by the use of 5-acyloxypyrazoles of polymeric nature, such as the products described in copending applications Serial Numbers 624,587, now Patent No. 2,567,750, and 682,137, now U. S. Patent No. 2,476,988, by the use of 5-acyloxypyrazoles which contain long side chains, such as l- (3-stearamidophenyl) -3-methyl-5-pyrazolyl ethyl carbonate, l-phenyl- -stearyl-5-pyrazolyl ethyl carbonate, by the use of 5-acyloxypyrazoles which are relatively insoluble in the photographic processing solutions.

Certain of the aldehydes containing 5-acyloxypyrazole groups described in copending application Serial Number 667,125, now U. S. Patent No. 2,476,987, are non-diffusing. Acid chlorides containing fi-acyloxypyrazole groups as described in application Serial Number 657,629, filed March 27, 1946, now U. S. Patent No. 2,476,986, may be used to prepare products which are fast to diffusion as, for example, by reaction with high molecular weight amines, such as benzidine, p,pdiaminodiphenyl ether, etc., or by reaction with polymeric materials, such as gelatin, polyvinyl alcohol and its partially substituted esters and acetals, partially hydrolyzed cellulose esters, hydrolyzed vinyl ester-olefin-interpolymers, etc.

The acyloxypyrazoles may also be immobilized through suitable choice of the aoylating reagent. Thus, 1-phenyl-3methyl-5pyrazolone may be treated with long chain or polymeric acid chlorides or anhydrides, e. g., stearoyl chloride, dodecoyl chloride, polymethacrylyl chloride and maleic anhydride interpolymers with, for example, styrene and vinyl chloride. This type of immobilization is of considerable interest since the final color-developed film can be treated with hydrolytic agents, such as dilute caustic, leading to removal of the uncoupled color formers.

It is also possible to prepare 5acyloxypyrazoles containing two pyrazolone nuclei coupled through the acyloxy radicals, e. g., by treatment of two moles of 1-phenyl-3-methyl-5-pyrazolone with one mole of a diacid chloride, such as adipyl chloride. Similarly by treatment of a 5-pyrazclone with a dibasic acid anhydride, a 5-acyloxypyrazolone containing an acid group is formed, for example, maleic anhydride and 1-phenyl-3- methyl-5-pyrazolone gives In place of the specific aromatic amino de veloping agent described in the examples, there may be substituted various other specific agents of this type. These agents have an unsubstituted amino group which apparently enables the oxidation product to. couple with the5-acyloxypyrazoles. Such agents include the mono-, di-, and tri-amino aryl compounds and compounds formed therefrom by substitution in the amino groups as well as in the ring. The preferred developing agents in the process of dye coupling development are derivatives of p-phenylenediamine, and particularly the asymmetric di-N-substituted pphenylenediamines, for example, p-amino-dimethylaniline, 2 amino-5-diethylaminotoluene, etc. These aromatic amino developing agents may be used in the form of their salts which may be organic or inorganic. The salts are, in general, more stable than the free bases. As examples of suitable salts there might be mentioned the hydrochloride, sulfate, oxalate, etc.

The photographic layers and emulsions may also contain the usual sensitizers, such as the cyanine and carbocyanine salts and bases and the cyazines and carbocyazine salts and bases, em ployed to extend the sensitivity of the photographic emulsions.

The coupler compositions of this invention may also be used in the preparation of positive dye images by developing an exposed silver halide emulsion with a non-coupling developer, then sitposing to light, and developing with a coupling aromatic amino developer, that is, by a color reversal process. Removal of the metallic silver by conventional methods yields a positive dye image.

A major advantage of the 5-acyloxypyrazole color formers is that they yield more stable compositions than the corresponding S-pyrazolones from which they are derived. Problems associ ated with the reactivity of the B-pyrazolones, for example, self-condensation to colored products leading to stained films, are thus avoided or minimize. Because of this stability, it is also possible to prepare complex color formers containing groups which would be impractical with the 5-pyrazolones, e. g., aldehyde groups. In addition, the 5-acyloxypyrazoles are more resistant to oxidation than the B-pyrazolones. The acyl group can also be used to introduce substituents of a special nature, e. g., solubilizing or immobilizing groups, which are later eliminated from the molecule as indicated above.

The exact mechanism by which these new color formers function to produce dye images is not known with certainty. It is surprising that any color is produced since there is no active methylene group in the 5-acyloxypyrazoles. It appears probable that coupling takes place with simultaneous or prior elimination of the acyl group. The relative ease of color coupling varies to some extent with the nature of the acyl group as might be expected. Thus, the sulfonates are slowest to couple and in some cases it is desirable to subject them to a hydrolytic step prior to coupling in order to achieve high color densities. Many photographic emulsions are prepared under alkaline conditions favorable to the hydrolysis of compounds of this type and, although it has not been established, it is possible that hydrolysis of the 5-acyloxypyrazoles may take place to some extent. If such a hydrolysis does take place, the acid liberated would be neutralized by the alkali present.

As many widely different embodiments of this invention can be made without departing from the spirit and scope thereof, it is to be understood that the invention is not to be limited except as defined by the claims.

What is claimed is:

1. A colloid silver halide emulsion havingadded thereto a color former having the general formula methyl, ethyl, isopropyl, phenyl, carboxyphenyl,

nitrophenyl, methoxyphenyl, chlorphenyl, benzyl and carbethoxy methyl, and R is a radical taken from the group consisting of methyl, propanol-2- sulfonic acid-3, p-sulfoethyl, fl-carboxyethyl, phenyl, carboxyphenyl, sulfophenyl chlorophenyl, nitrophenyl, aminophenyl, N-substituted carbamylphenyl, N-substituted sulfamylphenyl, CHsOOCNHCsH4-, carboxymethoxyphenyl pyridyl, and benzthiazolyl, and ZY is an acyl radical.

2. A photographic element hearing at least one hydrophilic colloid silver halide emulsion layer having added thereto a color former having the general formula HC-G-R 4 a ZYC5 2N wherein Y is a member taken from the class consisting of carbonyl and sulfonyl radicals, R is a radical taken from the group consisting of methyl, ethyl, isopropyl, phenyl, carboxyphenyl, nitrophenyl, methoxyphenyl, chlorphenyl, benzyl and carbethoxy methyl, and R is a radical taken from the group consisting of methyl, propanol-2- sulfonic acid-3, ,B-sulfoethyl, p-carboxyethyl, phenyl, carboxyphenyl, sulfophenyl, chlorophenyl, nitrophenyl, aminophenyl, N-substituted carbamylphenyl, N-substituted sulfamylphenyl, CI-bOOCNHCsH4-, carboxymethoxyphenyl pyridyl, and benzthiazolyl, and Z-Y- is an acyl radical.

3. A photographic developer composition comprising a weak alkali, a primary, aromatic, amino developing agent and an added color former having the general formula wherein Y is a member taken from the class consisting of carbonyl and sulfonyl radicals, R is a. radical taken from the group consisting of methyl, ethyl, isopropyl, phenyl, carboxyphenyl, nitrophenyl, methoxyphenyl, chlorphenyl, benzyl and carbethoxy methyl, and R is a radical taken from the group consisting of methyl, propanol-2- sulfom'c acid-3, fl-sulfoethyl, p-carboxyethyl, phenyl, carboxyphenyl, sul-fophenyl, chlorophenyl, nitrophenyl, aminophenyl, N-substituted carbamylphenyl, N-substituted sulfamylphenyl, CH3OOCNHCsH4-, carboxymethoxyphenyl pyridyl, and benzthiazolyl, and ZY is an acyl radical.

4. A photographic element bearing at least one hydrophilic colloid silver halide emulsion layer having added thereto a color former of the formula is an acyl radical and Ar is an aryl radical.

5. A photographic element bearing at least one hydrophilic colloid silver halide emulsion layer having added thereto a color former of the formula wherein wherein R' is an alkyl radical of 1 to 2 carbon atoms and Ar is an aryl radical.

6. A photographic element bearing at least one hydrophilic colloid silver halide emulsion layer having added thereto a color former of the formula H300 0 0- 0- (J-CH:

7. A photographic element hearing at least one hydrophilic colloid silver halide emulsion layer having added thereto a color former of (the formula o- -HNC o- N- N OHz-O I H5o2o0o-o-o C-CH;

on 8. A photographic element bearing at least one hydrophilic colloid silver halide emulsion layer having added thereto a polyvinyl acetal color former which contains recurring units of the formula CH2 C HNO 0- NN (m-(f l H (g HsCzOOC-O-C C--CH3 ELMORE LOUIS MARTIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS OTHER REFERENCES Weissberger, Investigation of Pyrazole Compounds IV, etc., J. A. C. S. 65, pages 1495 to 1502 (1943), all cited.

Weissberger, Investigation of Pyrazole Compounds VII, etc., J. A. C. S. 66, pages 1851 to 1855 (1944 all cited.

Claims (1)

1. A COLLOID SILVER HALIDE EMULSION HAVING ADDED THERETO A COLOR FORMER HAVING THE GENREAL FORMULA