US3671259A - Photographic bleaching and antifogging agents - Google Patents

Abstract

AMINOMETHYLQUINONES AND SALTS THEREOF HAVING THE GENERAL FORMULA:

R1,(A-CH2-)N-P-BENZOQUINONE (I)

R1,(A-CH2-)N-O-BENZOQUINONE (II)

WHEREIN R1 REPRESENTS HYDROGEN, AN ALKYL GROUP (INCLUDING AN ARALKYL GROUP), AN ARYL GROUP OR A-CH2A GROUP; N REPRESENTS AN INTEGER OF FROM 1 TO 3; A REPRESENTS ANY ONE OF THE GROUPS:-NHR2HX.

-N(-R3)(-R4), -N(-R3)(-R4).HX AND -N+(-R3)(-R4)(-R5).X(-)

R2,R3 AND R4 EACH REPRESENT AN ALKYL GROUP (INCLUDING AN ARALKYL GROUP), AN ALKENYL GROUP, AN ARYL GROUP, ETC. OR R3 AND R4 WHEN TAKEN IN COMBINATION WITH THE NITROGEN ATOM TO WHICH THEY ARE ATTACHED REPRESENT A MONOVALENT, HETEROCYCLIC GROUP; R5 REPRESENTS AN ALKYL GROUP INCLUDING AN ARALKYL GROUP; AND X REPRESENTS AN ANION; WITH THE PROVISION THAT EACH-(CH2A) GROUP IS SUBSTITUTED AT A POSITION ORTHO TO AN OXO GROUP ON THE QUINONE RING; ARE USEFUL AS BLEACHING AGENTS AND AS FOG INHIBITING AGENTS.

Description

United States Patent Int. Cl. G03c 1/34 US. Cl. 96-109 9 Claims ABSTRACT OF THE DISCLOSURE Aminomethylquinones and salts thereof having the general formula:

R (CHzAh or R wherein R represents hydrogen, an alkyl group (including an aralkyl group), an aryl group or a -CH A group; n represents an integer of from 1 to 3; A represents any one of the groups: --NHR -HX,

. R HX and ii n -x R R and R each represent an alkyl group (including an aralkyl group), an alkenyl group, an aryl group, etc. or R and R when taken in combination with the nitrogen atom to which they are attached represent a monovalent, heterocyclic group; R represents an alkyl group including an aralkyl group; and X represents an anion; with the provision that each -(CH A) group is substituted at a position ortho to an oxo group on the quinone ring; are useful as bleaching agents and as fog inhibiting agents.

This invention relates to novel aminomethylquinone compounds and salts thereof, and to the art of photography. More particularly, this invention relates to aminomethylquinones and the acid salts and quaternary ammonium salts of such aminomethylquinones, and to the use of such compounds and salts as photographic bleaching agents for silver and as fog inhibiting agents.

In photographic color processes, such as those in which a colored image is formed by development with an aromatic primary amine developing agent in the presence of a coupler compound, the silver images formed in the development are generally present in the emulsion layer after the dye images are formed. These silver images are generally removed by converting them to a silver salt which is soluble or which is removed by a silver salt solvent, such as, an alkali metal thiosulfate.

A bleach bath containing quinone, acid and an organic solvent has been used to convert silver images to a silver salt in the presence of a developed dye image. However, this bath cannot be used in the final stages of a color process because it destroys the dyes, as well as converts the silver to a silver salt. In addition, while compounds such as quinone are known to bleach silver in acidic solution, such compounds suffer from the fact that they are water-insoluble and also insoluble in dilute mineral acids. Prior art acid quinone bleach solutions release toxic vapors.

During development of a silver halide emulsion, small amounts of silver halide tend to be reduced to metallic silver, even though they have not been light exposed and have no latent image. This reduction of silver ion to silver produces a background fog which is more specifically referred to as chemical fog.

Chemical fog, apparent in most silver halide systems, has been reduced by prior art methods of processing exposed silver halide material in the presence of compounds which restrict development of unexposed silver halide. Such compounds may be incorporated in the silver halide emulsion or in the processing solutions for developing such silver halide emulsions. Fog inhibiting compounds have been found which have a chemical fog inhibiting effect on emulsions which have been subjected to high temperature and high humidity conditions (emulsion stabilizers), and on emulsions which have not been exposed to adverse storage conditions (antifoggants). It would be desirable to provide a new class of fog inhibiting agents.

It is therefore an object of the present invention to provide novel bleaching agents for bleaching silver images in the presence of color-developed dye images.

Another object of the present invention is to provide a bleach bath that does not release toxic fumes and is comprised of a novel class of water-soluble, photographic bleaching agents for silver.

Still another object of the present invention is to provide a method for converting silver images to a silver salt without destroying the dye images in the emulsion layer.

Another object of this invention is to provide a novel class of fog-inhibiting agents for photographic silver halide emulsions.

A further object of the invention is to provide a photographic element having incorporated therein a fog inhibiting agent.

These and other objects of the present invention are accomplished by providing photographic bleaching agents and fog inhibiting agents consisting of aminomethylquinones and salts thereof having the following general formula:

( 0 (II) 0 II I! o R1 (011m) or R1 I J (JHZA n wherein R represents hydrogen, an alkyl group (including an aralkyl group), an aryl group or a -CH A group; n represents an integer of from 1 to 3; A represents any one of the groups: NHR -HX,

R R and R each represent an alkyl group (including an aralkyl group), an alkenyl group, an aryl group or R and R represent the nonmetallic atoms which when taken in combination with the nitrogen atom to which they are attached form a monovalent, heterocyclic group; R represents an alkyl group including an aralkyl group; and X represents an anion; with the provision that each (CH A) group is substituted at a position ortho to an oxo group on the quinone ring.

The foregoing aminomethyl substituted pand o-quinones and their salts are desirably employed as bleaching agents in photographic silver bleach solutions. The aminomethylquinones of the present invention are soluble in water and are soluble in dilute acid solutions. Thus, the compounds of the present invention are more easily and effectively employed as silver bleaching agents than are previous bleaching agents, such as, water-insoluble quinones.

In addition, the aminomethylquinones of the present invention are advantageously incorporated in photographic silver halide emulsions to provide a high degree of fog inhibition.

Representative R groups in Formulas I and II include hydrogen, an alkyl group having from 1 to 25 carbon atoms, e.g., methyl, ethyl, propyl, isopropyl, butyl, hexyl, cyclohexyl, decyl, dodecyl, octadecyl, docosyl, etc., a hydroxyalkyl group, e.g., fl-hydroxyethyl, w-hydroxybutyl, etc., an alkoxyalkyl group, e.g., B-methoxyethyl, w-butoxybutyl, etc., a carboxyalkyl group, e.g., B-carboxyethyl, w-carboxybutyl, etc., a sulfoalkyl group, e.g., p-sulfoethyl, w-sulfobutyl, etc., a 'sulfatoalkyl group, e.g., B-sulfatoethyl, w-sulfatobutyl, etc., an acyloxyalkyl group, e.g., B-acetoxyethyl, 'y-acetoxypropyl, w-butyryloxybutyl, etc., an alkoxycarbonylalkyl group, e.g., fi-methoxycarbonylethyl, w-ethoxycarbonylbutyl, etc., and an aralkyl group, e.g., benzyl, phenethyl, etc.; an aryl group, e.g., a phenyl group (e.g., phenyl, tolyl, methoxyphenyl, chlorophenyl, bromophenyl, etc.) and a naphthyl group (e.g. a-naphthyl, fl-naphthyl, etc.); and an aminomethyl group (e.g., dirnethylaminomethyl, pyrrolidinomethyl, morpholinomethyl, etc.).

Representative R R and R groups in Formulas I and II include those alkyl groups and aryl groups which are representative of R and in addition, include an alkenyl group, e.g., an allyl group, e.g., allyl, methallyl, Z-butenyl, etc., a l-alkenyl group, e.g., a l-propenyl, e.g., l-propenyl, l-butenyl, etc. and R and R (in Formulas I and II represent the nonmetallic atoms which when taken in combination with the nitrogen atom to which they are attached form monovalent, heterocyclic groups including:

-N/ N k, N/ -N NkHa and the like.

Representative R groups in Formulas I and II include those alkyl groups representative of R R R and R X, in Formulas I and II, represents an acid anion, e.g., chloride, bromide, iodide, nitrate, thiocyanate, sulfamate, perchlorate, p-toluenesulfonate, methyl sulfate, ethyl sulfate, etc.

The aminomethylquinones and their salts are advantageously prepared by first forming the corresponding hydroquinones and catechols employing the Mannich condensation, for example, as follows:

on memo mum-r @(ommu CH2N R2 EN 0 RN 0 Hz (in excess) The free base is produced by neutralizing the acid salt with, for example, ammonium hydroxide or sodium b1- carbonate solution:

CH NRQ ZH O 2NH4NO3 BENCH:

The quaternary methylammonium quinones are prepared by reacting the aminomethyl hydroquinone with methyl-p-toluene sulfonate (MePTS) and subsequently oxidizing the resulting material with concentrated nitric acid, for example:

Suitable quaternizing agents that are used include the dialkyl sulfates, the alkyl halides, the aralkyl halides, the alkyl esters of aryl sulfonic acids, etc. Specific quaternizing agents include, for example, dimethyl sulfate, diethyl sulfate, dipropyl sulfate, dibutyl sulfate, ethyl bromide, ethyl chloride, methyl iodide, ethyl iodide, n-butyl iodide, benzyl chloride, benzyl bromide, methyl-p-toluene sulfonate, butyl-p-toluene sulfonate and ethyl benzenesulfonate. 1

As previously mentioned, the present aminomethylquiones and salts are advantageously employed as silver bleaching agents and as'fog inhibiting agents. The aminomethylquinones are advantageously employed as fog inhibiting agents over a wide range of concentrations. The

optimum amount of a particular aminomethylquinone or evolution of nitrogen dioxide fumes subsides and all of salt will vary somewhat from emulsionto..emulsiomand the.hydroquinone dissolves. The reaction mixture is poured from aminomethylquinone to aminomethylquinone The into one liter of cold ethanol. A yield of 82 percent of specific optimum amount to be incorporated in an emul- Compound 1, 2,5-bis(piperidinomethyl)-p-quinone dinision is determined for any particular emulsion by running tric acid salt, M.P. 183-185 C. is obtained.

a series of tests in which the quantity-of.aminomethyl-..-. AnalysinTCalcd. (percent): C, 50.5; H, 6.6;.N, 13.1.

quinone is varied over a given range. For example, a typical amount of aminomethylquinone is in the range from about .005 g. to about 2.0 g. of the aminomethylquinone per mole of silver halide.

Likewise, the concentration of aminomethylquinone employed as a silver bleaching agent is advantageously varied over a wide range, and determination of the optimum concentration is well within the skill of those work- I Found (percent): C, 50.2; H, 6.8; N, 12.4.

Compounds 2-8 The 2,5-bis(aminomethyl)quinone-nitric acid salts of the example in the following table are prepared according to the procedure substantially as described for Com- TABLE I Analysis of" Melting Calculated Found Percent point,

.... ..N(CH1)1 78 169-170 41.4 5.8 10.1 41.8 as 15.0

s N(C2H5)1 171-172 47.5 7.0 13.9 47.8 7.5 13.8

1 Decomposition.

ing in the art. Thus, for example, between about 0.1 and about 1.0 mole of aminomethylquinone per liter of aqueous bleach solution isadyantageously employed.

The following syntheses of representative compounds are included for a further understanding of our invention:

"Compound 1 Three moles of piperidinepare added slowly to a solution comprising three moles of paraformaldehyde and 500 ml. of isopropanol. The mixture is warmed with care on a steam bath while 1 mole of hydroquinone and 500 ml. of isopropanol are added. Heating on a steam bath is continued for 4 to 6 hours during which time white solids are precipitated. After removal of a portion of the solvent, the solids are rfiltered, washed with ether and dried. Fifty grams of the 2,5-bis(piperidinomethyl)hydroquinone formed 'isadded slowly to 200 ml. of cold concentrated nitric acid. The mixture is stirred until the HaA ACH

" {Them 11 I I Analysis ot 7 -Melting Calculated Found Y Percent point, A yield "o. o" H N o" H N- Compound No.: a I

14 -N(CH3), 59 45-50 64.8 8.2 12.6 63.8 8.6 13.6 15 N(C4H5)4 99 168-170 69.0 9.4 10.1 68.5 9.4 9.5

Compounds 16-21 In order to prepare the quinones of Table III, below;

""The results-are set forth in the following Table III,

twenty grams of a 2,5-bis-(N-methylaminomethyl)hydrobelow:

TABLE III ,7

- 7 I Analysis of- I Melting Calculated Found 9 Percent point, -A X yield C. 0 H N S O H N S Compound Number:

16 CH3 N03 80 193-194 52.3 7.5 12.2 51.9 7.1 12.2

17 CH8 N01 96 171-172 46.8 6.6 11.9 46.6 6.4 11.8

l 18 -CH3 C1H1s'0'a 65 145 59.4 6.6 4.3 9.9 58.9 6.3 4.2 9.6

19 0H3 mor 64 171-172 40.1 6.1 17.0 .39.8 6.2 17.2

\/ -N N(CH9)2 11192 01111803 infuse-18561.1 7.4 3.8. 61.3 7.4 41.--.--

l Decomposition.

quinone-bis-p-toluenesulfonate are mixed with 20 mls. g. Compoundsp22 28.

of concentrated nitric acid. Thirty mls. of ethanolare added to insure complete solution of the. hydroquinone derivative and a complete reaction. The product is precipitated by addition of 250 mls. of ethyl acetate, filtered and washed with ethyl acetate and dried. This procedure is employed with the appropriate 2,5-bis(N-methylaminomethyl-fifp-henyl Lcat'echol' swam/(ps7. from reaction methyl) hydroquinone-bis-p-toluenesulfonatesto 'maketlie corresponding quinone Compounds 1 62l having the following formula:

CHzA

olution with the to,

60 A mixture of*72 grams of-paraf o'rr'naldehyde, one liter is opropanol ond 2:4'im0les of pipefidine 'is'heated on a steam bath until 'it becomes homogeneous. 372 grams of phenyl catechol are added tothe-gsolution. The mixture is refluxed for 15 minutes, during which timelh 3-aminomixtu'reiAfter cooling, the solid precipitate is collected, .washedwith etherarid driedfOne-t'e'rith of a mole of'the a-minometh'yl '5j-phenyl catecholis slurriedfin cold etee onegon addition ofunitri'c'acidfthe catechol 'goes into ftionfof. a' deep-red solution. Forther'addition "of V c-"acidcausesjhe precipitate "of a solid .material '(Co pound 2 2)'whicl1 is filtered, washed with cold; aceto' 'd dried under vacuumf'Ihe'foregoing procedure is repeated, employing various 3 aminomethyl-S-phefiYl catechols, resulting 'in Compounds 23 following for- 10 i.e., Compounds 29 and 31, respectively, are precipitated and crystallized by alternate additions and decantations of an acetone-ligroin (1:5) mixture. The 3-azabicyclo- (3.2.2)nonane derivative, i.e., Compound 32, is isolated readily from the reaction mixture when acetone is employed as a reaction solvent. The piperidine derivative, i.e., Compound 30, is obtained from the reaction mixture by drying under vacuum and the residue is isolated with- AC H out further purification. The resulting Compounds 29-32 2 :HNOs conform to the formula.

ll (3am 11011 0 '2HN03 112A The results are set forth in Table V, below:

TABLEV Analysis of- Melting Calculated Found Percent point, -A yield C. 0 H N c H N Compound Numberz' The results are set forth in Table IV, below:

TABLE IV Analysis of Melting Calculated Found Percent point, -A yield C.CHNCHN Compound No.:

27 N(CH3)2 72' 158 57.6 5.5 9.6 58.1 5.3 6.6 28 -..N(C2H5)2 61 145 61.5 6.1 8.4 61.8 6.1 8.3

1 Decomposition.

Compounds 29-32 Compounds 33-35 Various 3,6-bis(aminomethyl) o quinone-nitric acid salts are prepared in a manner identical to the procedure employed in preparing the 2,5-bis(aminomethyl)quinonenitric acid salts, such as, Compounds 1 and 2. The resulting salts have the formula:

2HNOa -CH2A TABLE VI Analysis of- Melting Calculated Found point, -A. 0. 0 H N 0 H N Compound Number:

l Decomposition;

Compounds 36-46 N-substituted aminomethylquinones having the formula:

An N-substituted aminomethylhydroquinone hydrochloride salt in an amount of 5 grams is added'to mls." of concentrated nitric acid which is maintained cold by an ice-water bath. The colorless solids go into solution with the formation of a yellow color and the evolution of nitrogen dioxide gas. The reaction mixture is allowed to stand for minutes and is then treated with a 1:1 isopropyl alcohol-methyl ethyl ketone mixture that had been previously chilled in a Dry-Ice-acetone bath. The precipitated compounds are collected by filtration and dried under vacuum. The sample is recrystallized from absolute ethanol. This procedure is employed in the preparation of each of the compounds of the present invention as set forth in Table VII, below:

Compound 47 A mixture of 5.35 moles of morpholine, 5.35 moles of paraforrnaldehyde, 700 ml. of benzene and 700 ml. of 2-(2-ethoxyethoxy)ethanol is heated and 500 ml. of distillate removed. One mole of hydroquinone in 350 ml. of methanol is then slowly added to the heated mixture and distillate again removed until the reflux temperature reaches C. The reaction mixture is refluxed for twenty hours, cooled, and the tetrakis(morpholino)hydroquinone crystals formed are separated and washed with ether to yield 280 g. with a melting point of 254-257 C. After recrystallization from 2-(2-ethoxyethoxy)ethanol, the tetrakis (morpholino)hydroquinone has a melting point of 256-257" C. Fifty grams of the recrystallized tetrakis(morpholino)hydroquinone are'added slowly to 200 ml. of cold concentrated nitric acid. The mixture is stirred until the evolution of nitrogen dioxide fumes subsides and all of the hydroquinone derivative has dissolved. The reaction'mixture is poured into'one liter of cold ethanol. The tetrakis(morpholino)-p-quinone nitric acid salt that precipitates is separated from the mixture by filtration and the salt is washed with' ethanol. Compound 47, i.e., tetrakis(morpholino)-p-quinone prepared by neutralizing the acid salt with an aqueous sodium bicarbonate solution, filtering the solid product from the reaction mixture and recrystallizing from ethyl acetate has a melting point of 168 C. dec.

TABLE VII Analysis 01- Melting Calculated Found Percent point R R yield 0.) C H N C H N m ouud number:

Co 3% -C(CH3) -CZH 43. 9 I 151-152 54.9 7.1 9.9 54 5 7. 0 9.5

37. -C(CH C H -n 75.4 159-160 56.4 7.4 9.4 56.3 7.4 9.7 38. C(CH -C4Hq-1l 87.6 137-138 57.7 7.7 9.0 57.5 7.8 8.0 39 -C(CH -CHz-C5H5 82.7 168-169 62.4 6.4 8.1 62.1 6.4 7.9 40- C 3 CH3 96.6 -151 47.4 5.3 12.3 46.9 5.4 12.7 41--- -CH -C2H5 77.9 162-163 49.6 5.8 11.6 49.2 5.8 11.4 42." CH -C;H1-n 95.2 167-168 51.6 6.3 10.9 51.3 6.5 10.7 43... .CH;, -CH(CH3)2 85.7 148-149 51.6 6.3 10.9 51.5 6.2 10.8 44 CH 4Hq-I1 89.8 162-163 53.3 6.7 10.4 53.1 6.4 10.7 45. OH;; CH2C0H5 75.3 165-166 59.2 5.3 9.2 59.1 5.2 9.0 46 -C1gH31 -CH3 73.0 90-95 66.9 9.9 6.0 66.6 10.0 6.6

Analysis.Calcd. (percent): C, 61.4; H, 8.2. Found (percent): C, 61.4; H, 7.9.

Our compounds of Formulas I and II are advantageously incorporated in silver halide emulsion layers as an antifogging agent. Emulsions containing our antifoggants are advantageously used in a wide variety of photographic elements of the black-and-white types and of the multilayer, multicolor types. The antifogging agent is advantageously added as a solution in a suitable solvent to the silver halide emulsion as an addenda during the time after the emulsion is washed (if it is washed) and just prior to coating. Our compounds are advantageously added in the concentration range from about 0.005 g. to about 2.0 g. per mole of silver and preferably in the range of from about 0.01 g. to about 1.0 g. per mole of silver.

The silver halide emulsions used in our invention comprise silver chloride, silver bromide, silver bromoiodide, silver chlorobromoiodide or mixtures thereof. The emulsions range from coarse grain to fine grain and are prepared by any of the well-known procedures. Surface image emulsions, internal image emulsions, or mixtures of surface and internal image emulsions are used as described in Luckey et al., U.S. Pat. 2,996,382.

The silver halide emulsions are unwashed or washed to remove soluble salts. In the latter case, the soluble salts are advantageously removed by chill-setting and leaching or the emulsion is advantageously coagulationwashed, e.g., by the procedures described in Hewitson et al., U.S. Pat. 2,618,556; Yutzy et al., U.S. Pat. 2,614,928; Yackel, U.S. Pat. 2,565,418; Hart et al., U.S. Pat. 3,241,- 969; and Waller et al., U.S. Pat. 2,489,341.

The emulsions are advantageously sensitized with chemical sensitizers, such as, with reducing agents; sulfur, selenium or tellurium compounds; gold, platinum or palladium compounds; or combinations of these. Suitable procedures are described in Sheppard et al., U.S. Pat. 1,623,499; Walter et al., U.S. Pat. 2,399,083; McVeigh, U.S. Pat. 3,297,447; and Dunn, U.S. Pat. 3,297,446.

Likewise, the silver halide emulsions advantageously contain speed-increasing compounds, such as, polyalkylene glycols, cationic surface active agents and thioethers or combinations of these as described in Piper, U.S. Pat. 2,886,437; Dann et al., U.S. Pat. 3,046,134; Carroll et al., U.S. Pat. 2,944,900; and Goffe, U.S. Pat. 3,294,540.

The photographic and other hardenable layers used in the practice of our invention are advantageously hardened by various organic or inorganic hardeners, alone or in combination, such as, the aldehydes, and blocked aldehydes, ketones, carboxylic and carbonic acid derivatives, sulfonate esters, sulfonyl halides and vinyl sulfonyl ethers, etc.

The photographic emulsions and elements described in the practice of our invention advantageously contain various colloids alone or in combinations as vehicles, binding agents and various layers. Suitable hydrophilic materials include both naturally-occurring substances, such as. proteins, for example, gelatin, gelatin derivatives, cellulose derivatives, polysaccharides, such as, dextran, gum arabic and the like; and synthetic polymeric substances, such as, water-soluble, polyvinyl compounds like poly(vinylpyrrolidone), acrylamide polymers and the like.

The described photographic emulsion layers and other layers of a photographicele'ment employed in the practice of our invention advantageously also contain alone or in combination with hydrophilic,Water-permeable colloids, other synthetic polymeric compounds, such as, dispersed vinyl compounds, such as, an latex form and particularly those which increase the dimensional stability of the photographic materials.

Those photographic layers of the present invention are advantageously coated on a wide variety of supports. Typical supports include cellulose nitrate film, cellulose ester film, poly(vinylacetal) film, polystyrene film, poly- (ethvlene terephthalate) film. polycarbonate film and related films or resinous materials, as well as glass, paper,

14 metal and the like. Typically, a flexible support is employed, especially a paper support, which can be partially acetylated or coated with baryta and/or an alpha-olefin polymer, particularly a polymer of an alpha-olefin containing 2 to 10 carbon atoms such as polyethylene, polypropylene, ethylenebutene copolymers and the like.

Spectral sensitizing dyes are used to confer additional sensitivity to the light sensitive silver halide emulsion of the multilayer photographic elements of the invention. For instance, additional spectral sensitization can be obtained by treating the emulsion with a solution of a sensitizing dye as a final step or at some earlier stage. Sensitizing dyes useful in sensitizing such emulsions are described, for example, in Brooker et al., U.S. Pat. 2,526,- 632, issued Oct. 24, 1950; Sprague, U.S. Pat. 2,503,776, issued Apr. 11, 1950; Brooker et al., U.S. Pat. 2,493,748; and Taber et al., U.S. Pat. 3,384,486. Spectral sensitizers which can be used include the cyanines, merocyanines, complex (trior tetranuclear) merocyanine, complex (trior tetranuclear) cyanine, holopolar cyanines, styryls. hemicyanine (eg., enamine hemicyanines), oxonols and hemioxonols.

Any of the color-forming couplers used in photographic elements are used to advantage in our photographic materials. Included among the phenol and naphthol cyan-dyeforming couplers used to advantage are those described by the following U.S. Pats.: 2,423,730, 2,474,293, 2,521,- 908, 2,725,291, 2,801,171, 3,253,294, etc. Included among the ketomethylene yellow-dye-forming couplers used to advantage are those described in U.S. Pats. 2,298,443, 2,778,658, 2,801,171, 2,875,057, 3,253,924, 3,277,155, etc. Included among the S-pyrazolone magenta-dye-forming couplers used to advantage are those described in U.S. Pats. 2,600,788, 2,801,171, 3,252,924, etc.

Dispersing agents for color-forming couplers and the dispersing techniques used to advantage include those set forth in Jelley et al., U.S. Pat. 2,322,027; Mannes et al., U.S. Pat. 2,304,940; Fierke et al., U.S. Pat. 2,801,171, etc.

The light-sensitive silver halide emulsion layers are arranged on the support of a multicolor element in any order; however, in an especially advantageous arrangement, the red-sensitive layer is coated nearest the support, with the green-sensitive layer and the blue-sensitive layer over the red-sensitive layer in that order. Hydrophilic colloid interlayers between the light-sensitive layers, light-filtering layers, etc. are used to advantage.

The photographic layers used in the practice of this invention are coated by various coating procedures including dip coating, air knife coating, curtain coating or extrusion coating using hoppers of the' type described in Beguin, U.S. Pat. 2,681,294. If desired, 2 or more layers may be coated simultaneously by the procedures described in Russel, U.S. Pat. 2,761,791 and Wynn, British Pat. 837,095.

Our compounds of Formulas I and II are advantageously used as silver bleaching agents in bleach baths for converting developed silver salts in color-developed photographic elements, such as, those described in Mannes et al., U.S. Pat. 2,252,718, Jelley et al., U.S. Pat. 2,322,027, VanCampen, U.S. Pat. 2,956,879 and Carroll et al., U.S. Pat. 2,944,900. A typical bleach solution of our invention comprises from about 0.01 mole/l. to about 1.0 mole/ 1., preferably in the range of from about 0.05 to about 0.5 mole/l. of our compounds of Formulas I and II and advantageously contains addenda for adjusting the pH, e.g., an alkali (e.g., alkali metal hydroxides, etc.), an acid (e.g., sulfuric acid, phosphoric acid, acetic acid, citric acid, phthalic acid, etc.) to adjust the pH to a value in the range of from about 1.0 to about 6.5 and, preferably, in the range from about 1.5 to about 4.0, and acid salt to buffer the solution (e.g., alkali metal acid phthalate, alkali metal acid phosphate, alkali metal bisulfate, etc.), a water softening agent (such as, an alkali metal hexametaphosphate), an alkali metal bromide in concentrations from about .01 to about 3 moles/l. or a silver ion complexing agent, such as a 4-methy1imidazolinethione (e.g., 4-methylimidazolinethione), an alkali metal thiocyanate (e.g., sodium thiocyanate, potassium thiocyanate, etc.), thiourea, etc. Silver ion complexing agents are advantageously used at concentrations of 0.01 mole/l. and above.

The following examples are included for a further understanding of our invention:

EXAMPLES 1-5 Five samples of an unexposed, supported single-layer gelatinous silver halide emulsion coating containing a cyan-dye-forming coupler are processed under red light at a temperature of 21 C. in a process comprising subjecting the samples to an aqueous prehardening bath comprising 2 percent succinaldehyde for a period of two minutes, water washing for five minutes, treating with a color developer containing a pphenylenediamine color developing agent for a period of ninety minutes to assure complete, uniform fogging development resulting in optimum levels of silver and cyan dye, then water washing for a period of thirty minutes, fixing for a period of twenty minutes, employing the composition specified in Table VIII, below:

TABLE VIII Ingredient:

Sodium thiosulfate Concentration Sodium sulfite, desiccated 240.0 grams. Acetic acid, 28% 15.0 grams. Boric acid 48.0 cc. Potassium alum 7.5 grams.

Water to make, 1.0 liter. 15.0 grams.

water washing and drying. Meanwhile, five bleach solutions are prepared, each of which contain 18.6 grams of the silver ion complexing agent 4-methylimidazolinethione, 1 liter of Water and a bleaching agent in an amount shown in Table IX, below:

The pH of each bleach solution is 2.0 at a temperature of 23 C. The bleach solutions of Examples 1, 3 and 4 are adjusted to the desired pH with water, sodium hydroxide and sulfuric acid, respectively. Samples of the coatings processed in the manner previously described are partially immersed into the bleach solutions of Examples 1, 2, 3, 4 and 5 for periods of time ranging from: 2%. to 60 minutes in the bleach solutions of Examples 1 and 2; 1 to 40 minutes in the bleach solution of Example 3; seconds to 15 minutes in the bleach solution of Example 4; and 15 seconds to 5 minutes in the bleach solution of Example 5. Upon removal from each bleach solution, the samples are washed with water for 30 minutes and dried. Each of the five solutions bleaches the silver in the processed samples in proportion to the time of immersion. The density of the cyan dye image in the bleach samples is essentially unaffected. The aminomethylquinone bleaching agents are either in the acid salt or quaternized salt form in our acid bleach solutions so they do not pollute the air with toxic vapors as do prior art quinone bleach solutions.

Similar results are obtained when Examples 1-5 are repeated using equimolar amounts of other aminomethylquinones of Formulas I and II in place of the aminomethyl quinones used in Examples 1-5, showing that they are useful bleaching agents for silver bleaches in color photography and do not have any detrimental effect on the image dyes.

EXAMPLE 6 A high-speed, gelatino silver bromoiodide emulsion which has been panchromatically sensitized with a cyanine dye is divided into two portions. One portion is coated as a control on a cellulose acetate film support at a coverage of 4.94 g. of silver and 15.06 g. of gelatin per m2. To the other portion of the emulsion is added with intimate mixing 0.15 g. of Compound No. 36 per mole of silver and the resulting emulsion is coated on another piece of the cellulose acetate film support at the same silver and gelatin coating rates as the control. Two samples of each film coating are exposed on an Intensity Scale Sensitometer. One sample of the control and one sample of the coating containing Compound No. 36 are processed for five minutes in a developer solution having the composition:

. I G- p-Aminophenol sulfate 2.5 Sodium sulfate, desiccated 30.0 Hydroquinone 2.5 Sodium metaborate octahydrate 10.0 Potassium bromide 0.5

Water to make, 1.0 l.

unit.

EXAMPLES 7-22 The same procedure used for Example 6 is used in Examples 7-22, but using other high-speed gelatino silver bromoiodide emulsions, other aminomethyl quinone compounds of our invention at the coating rates and incubation times indicated in Table X. Each example has its own control. The results of Examples 7-22, as well as Example 6, are summarized in Table X.

TABLE X Compound Fog in density units Incubated Incu- Coating fog bation rate in 50% time Example Numg./mole Fresh RH, in number her Name ofAgfog 49 C. weeks 6 47 2,3,5,6-tetramorpholinomethyl-p-quinone .15 .08 .47 2 Control None 12 94 2 7...'.' 10 2.5-bis(morpholinomethyl)-p-quinone .09 .11 .64. 2 Control None .14 1.09 2

8 12 2,5-bis(3-azabicycl0[3,2,2,]nonan-3-ylmethyl)-p- .09 .16 .43 2

quinone.

TABLE X-Continued v Compound Fog in density units Incubated Incu- Coating fog bation rate in 50% time Example Numg./mole Fresh BE, in number ber Name of Ag fog 49 weeks Control None 14 1. 09

9-. 11 2,5-bis(pyrrolidinomethyl)-p-quinone 15 15 .34 2 Contr l None 15 71 2 13 2,5-bis(N-oycl0hexyl-N-methylaminornethyl)-p- .09 16 1. 69 2 quinone dinitric acid salt. Control None 14 1. 69 2 11 14 2,5-bis(dimethylaminomethyl)-p-quinone 15 17 50 2 Contr None 15 71 2 12 16 2,5-bis(N-methylpiperidinium-methyl)-p- .3 .21 1

quinone dinierate. Control None 13 32 1 13 17 2,5-bls(N-methylmorpholiniummethyl)-p- .3 11 .21 1

quinone dinitrate. Contr l None 13 32 1 14 1s 2,5-bis(N-methylpyrrolidiniummethyl)-p- .a .14 .32 1

quinone bis-p-toluenesulionate. Contro1 1 None 13 .32 1

15 20 2,5-bis(N,N-dimethyl-N-cyclohexylammonium- .3 12 .20 1

methyl) -p-quinone bis-p-toluene sulionate. Contr l None .13 .32 1

16 22 5-phenyl-fi-piperidinomethyl-o-quinone nitric- .15 .11 .36 2

acid salt. Contr l None 15 46 2 17 29 3,6-bis(morpholinomethyl)-4-phenyl-o-quinone 15 .13 .37 2

nitric acid salt. Contr l I None 15 46 2 18 30 3,6-bis(piperidinomethyl)4-phenyl-oquinone 11 .35 2

nitric acid salt. Control None 15 46 2 19 31 3,6-bis(pyrro1idinomethyl)-4-phenyl-o-quin0ne 15 .12 .31 2

nitric acid salt. Control I None 17 54 2 20 33 3,6431%?(piperidinomethyD-o-quinone nitric acid 12 13 24 1 so Control None 16 40 1 21.1. 34, 3,6-ls(morpholinomethyl)-0-quinone nitric acid 6 13 22 1 sa Control None 16 40 1 22 3,fi-bis(3-az abicyclo[3,2,2]-nonan-3-ylmethy1)-o- 12 19 .20 1

quinone nitric acid salt. Control None 16 1 The results obtained for Examples 6-22 show that in each We claim:

instance, the fog density for the incubated emulsion coatings containing our aminomethyl quinone compounds are substantially lower than the respective fog density for the incubated control emulsion coating. In addition to showing lower fog values in the incubated film coatings containing our compounds, fresh coatings of Compounds 36, 10, 17, 22, 29, 30, 31, 33 and 34 also show lower fog values than the respective controls. The results in Examples 622 illustrate the useful antifogging characteristics of our aminomethyl quinone compounds in high-speed, silver bromoiodide emulsion coatings. Similar improvements are shown when the compounds used inExamples 6-22 and other aminomethyl quinones of our invention are incorporated in one or more emulsion layers of a multilayer color film.

The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.

1. A photographic silver halide emulsion containing a fog inhibiting agent selected from the class consisting of those having the formulas:

R1 (CHzA)n and v (II) 0 ll R represents a group selected from the class consisting of an alkyl group, an alkenyl group and an aryl group; 1 R and R each represent a group selected from the class consisting of an alkyl group, an alkenyl group, an aryl group and the nonmetallic atoms which when taken in combination with the nitrogen atom to which they are attached form a monovalent, heterocyclic group; R repree sents an alkyl group; and X represents an anion; with the provision that each (CH A) group is substituted at a position ortho to an oxo group on the quinone ring.

2. The emulsion of claim 1 wherein the fog inhibiting agent is selected from those having the formula:

HzA

ACE

wherein A represents a group selected from the class con 4 sisting of and 4. The emulsion of claim 2 wherein the fog inhibiting agent is 2,5-bis(N-cyclohexyl-N-methylaminomethyl)-pquinone dinitric acid salt.

5. The emulsion of claim 1 wherein the fog inhibiting agent is selected from those having the formula: 0 II (onus i V wherein R represents a member selected from the class consisting of hydrogen and a phenyl group; n represents 1 or 2; and A represents a group selected from the class consistingof 7. The emulsion of claim 5 wherein the fog inhibiting 0 agent is 4-phenyl-G-piperidinomethyl-o-quinone nitric acid salt.

8. method for inhibiting fog in a photographic silver halide emulsion which comprises incorporating in saidv emulsion a fog inhibiting agent selected from the class consisting of those having the formulas;

and

OH2A)n wherein R represents a member selected from the class consisting of hydrogen, an alkyl group, an aryl group and a OHgA group; n represents an integer of from 1 to 3;

A represents a group selected from the class consisting of -NHR -HX N N -HX 1 5 and a -NR -X 21 R represents a group selected from the class consisting of an alkyl group, an alkenyl group and an aryl group; R and R each represent a group selected from the class consisting of an alkyl group, an alkenyl group, an aryl group and the nonmetallic atoms which when taken in combination with the nitrogen atom to which they are attached form a monovalent, heterocyclic group; R represents an alkyl group; and X represents an anion; with the provision that each --(CH A) group is substituted at a position ortho to an oxo group on the quinone ring.

9. The method of claim 8 wherein said fog inhibiting agent is selected from those having the formula:

consisting of:

wherein R and R when taken in combintion with the nitrogen atom to which they are attached form a monovalent, heterocyclic group and X represents an acid anion.

References Cited UNITED STATES PATENTS 3,396,022 8/1968 Dersch et a1. 96109 3,161,506 12/1964 Becker 96-109 3,563,754 2/1971 Jones et al. 96l09 3,449,122 6/1969 Kretchman et a1. 96109 NORMAN G. TORCHIN, Primary Examiner E. C. KIMLIN, Assistant Examiner US. Cl. X.Rt. 96-53