Classifications

• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
  • G03C7/00—Multicolour photographic processes or agents therefor; Regeneration of such processing agents; Photosensitive materials for multicolour processes
  • G03C7/30—Colour processes using colour-coupling substances; Materials therefor; Preparing or processing such materials
  • G03C7/32—Colour coupling substances
  • G03C7/327—Macromolecular coupling substances
  • G03C7/3275—Polymers obtained by reactions involving only carbon-to-carbon unsaturated bonds, e.g. vinyl polymers
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F20/00—Homopolymers and copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and only one being terminated by only one carboxyl radical or a salt, anhydride, ester, amide, imide or nitrile thereof
  • C08F20/62—Monocarboxylic acids having ten or more carbon atoms; Derivatives thereof

Definitions

• R is hydrogen, C -C alkyl or chlorine, X is -O or N(R) wherein R is hydrogen or lower alkyl, Y is a divalent hydrocarbon group which may be interrupted by oxygen and/or sulphur, and M is a cation.
• the polymeric compounds can be incorporated in hydrophilic colloid.
• the present invention relates to polymeric colour forming couplers and competing couplers and to photographic silver halide elements containing these polymeric compounds.
• Polymeric couplers are preferably used in the form of latices obtained by emulsion polymerization techniques with the aid of the usual addition polymerization initiators.
• interesting emulsion polymerisation techniques are for instance described in Belgian Pat. No. 669,971 according to which latices are formed of polymeric colour couplers by emulsion polymerisation in aqueous gelatin, and in United Kingdom Pat. No. 1,130,581 according to which latices are formed of polymeric couplers by emulsion polymerisation in water.
• polymeric couplers in hydrophilic colloid compositions in the form of latices have important advantages over the incorporation of the polymeric or nonpolymeric couplers in the form of solutions in water, water-miscible solvents or waterimmiscible solvents.
• latices may contain a high percentage of polymer e.g. concentrations up to 50 and nevertheless still possess a relatively low viscosity; when incorporating said latices into emulsions the viscosity of the latter is not influenced.
• latices there can be dispensed with the use of organic solvents or alkaline solutions as well as with special dispersing techniques for incorporating the coupler compounds.
• latices also poses a number of difficulties. For example, it is often required to add an extra amount of emulsifying agent when incorporating the latex into the hydrophilic colloid composition e.g. a silver halide emulsion in that the emulsifying agent used in the preparation of the latex does not suffice to stabilize the polymer particles in the hydrophilic colloid. Moreover, the ballast of emulsifying agent may give rise to foaming when dispersing the latex in the hydrophilic colloid and the coated layer often shows repellency spots, streaks and the like coating defects.
• an extra amount of emulsifying agent when incorporating the latex into the hydrophilic colloid composition e.g. a silver halide emulsion in that the emulsifying agent used in the preparation of the latex does not suffice to stabilize the polymer particles in the hydrophilic colloid.
• the ballast of emulsifying agent may give rise to foaming when dispersing the latex in the hydrophilic col
• Another object of the present invention is to provide latices of polymeric colour couplers and competing couplers that have reduced foaming tendency and do not give rise to coating defects in hydrophilic colloid coatings.
• Still another object of the present invention is to provide latices of polymeric colour couplers and competing couplers which have high compatibility with hydrophilic colloids more particularly gelatin and do not require an external surfactant for being dispersed into the hydrophilic colloid.
• a further object is to provide latices of polymeric colour couplers and competing couplers which comprise reduced ballast of emulsifying agent so that it is possible to obtain thinner hydrophilic colloid layers e. g. silver halide emulsion layers which results in increased sharpness.
• a still further object is to provide a photographic silver halide colour element comprising in a silver halide emulsion layer or in a hydrophilic colloid layer in water-permeable relationship with a silver halide emulsion layer, a said latex of a polymeric colour coupler or competing coupler.
• R is hydrogen, alkyl, preferably C C, alkyl, or chlorme
• X represents -O- or N(R')-wherein R is hydro gen or lower alkyl e.g. methyl,
• Y represents a divalent hydrocarbon group which may be interrupted by oxygen and/or sulphur e.g. alkylene, arylene e.g. phenylene, alkyleneoxyalkylene, alkylenephenylene and alkyleneoxyphenylene, in which the alkylene groups are preferably lower alkylene groups and include straight-chain and branched-chain alkylene, cycloalkylene and substituted alkylene e.g. alkylene substituted by halogen e.g. chlorine and bromine, alkoxy and phenyl, and in which the arylene groups include substituted arylene, and
• M represents a cation e.g. hydrogen, a metal atom e.g. sodium and potassium, ammonium and organic amine, e.g. diethanolamine, triethylamine.
• monomeric compounds corresponding to the above general formula I can be found in British Pat. No. 1,009,186 and US. Pat. No. 3,024,221. Particularly suitable results are obtained with mono- 3 mers in which Y stands for a straight-chain or branched-chain C C alkylene group i.e. with sulphoethyl, sulphopropyl and sulphobutyl esters of acrylic acid and a-substituted acrylic acids and to a less degree with the N-sulphoethyl, N-sulphopropyl and N-sulphobutyl acrylamides or a-substituted acrylamides.
• Y stands for a straight-chain or branched-chain C C alkylene group i.e. with sulphoethyl, sulphopropyl and sulphobutyl esters of acrylic acid and a-substituted acrylic acids and to a less degree with the N-sulphoe
• the present invention thus provides latices of polymeric compounds that are copolymers comprising recurring units derived from ethylanically unsaturated colour coupler or competing coupler monomers and recurring units derived from monomers corresponding to the above formula.
• the present invention further provides a photographic silver halide colour element comprising a support and at least one silver halide emulsion layer wherein the said silver halide emulsion layer and/or a hydrophilic colloid layer in water-permeable relationship therewith comprises a polymeric latex the polymer of which being a copolymer as defined above.
• polymeric couplers may also comprise units of copolymerized ethylenically unsaturated monomers that are not capable of oxidative coupling with aromatic primary amino compounds for example acrylic acid, a-chloroacrylic acid, a-alkacrylic acids, wherein the substituting alkyl contains from 1 to 4 carbon atoms e.g.
• esters and amides derived from acrylic acid, a-chloroacrylic acid and these a-alkacrylic acids such as acrylamide, methacrylamide, ethyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate and lauryl methacrylate
• vinyl esters such as vinyl acetate, vinyl propionate and vinyl laurate, acrylonitrile, methacrylonitrile, aromatic vinyl compounds such as styrene and its derivatives, e.g.
• vinyl toluene vinyl acetophenone and sulphostyrene, itaconic acid, citraconic acid, crotonic acid, vinylidene chloride, vinyl alkyl ethers such as vinyl ethyl ether, maleic acid esters, N-vinyl-2-pyrrolidone, N- vinylpyridine, 2- and 4-vinyl-pyridine.
• the ethylenically unsaturated monomers suitable for being copolymerized with the monomeric colour couplers or competing couplers and the monomeric sulphoesters or sulphoamides described above can be chosen so that the physical and/or chemical properties of the resulting copolymer such as its solubility, its flexibility, its thermal stability, etc., are favourably influenced.
• methacrylic acid and styrene when used together as comonomers e.g.
• the monomeric ethylenically unsaturated colour couplers or competing couplers for being copolymerised in accordance with the present invention are generally of the type respresented by the formula II II R wherein:
• R is hydrogen, alkyl, preferably C -C alkyl, or chlorine 4 Q is a colour coupler or competing coupler residue capable of coupling with an oxidized aromatic primary amine colour developing agent.
• the monomers represented by the above formula II comprise a residue Q of well known coupler compounds for example 1, a residue of a cyan-forming colour coupler of the phenol or naphthol type e.g. of the formula:
• A is a single chemical bond or a bivalent organic group linking the ethylenically unsaturated group of the formula II to the colour coupler residue
• R represents hydrogen, a substituent of the type well known in phenol or naphthol colour couplers such as halogen alkyl or aryl, or the atoms necessary to complete a fused-on benzene nucleus which may be substituted, and
• Y represents a hydrogen atom in the case of 4- equivalent couplers or a substituent which splits off upon colour development thus conferring to the colour coupler a 2-equivalent character e. g. a halogen atom such as chlorine, an acyloxy group, an alkoxy, aryloxy, or heterocycloxy group, an alkylthio, arylthio or heterocyclic thio group such as tetrazolylthio group, or phenylazo group etc.
• a halogen atom such as chlorine, an acyloxy group, an alkoxy, aryloxy, or heterocycloxy group, an alkylthio, arylthio or heterocyclic thio group such as tetrazolylthio group, or phenylazo group etc.
• R is substituent of the type well-known in the l-position of 2-pyrazolin5-one colour couplers e.g. alkyl including substituted alkyl e.g. haloalkyl such as fluoroalkyl, cyanoalkyl and benzyl, or aryl including substituted aryl e.g. phenyl which may be substituted by alkyl, halogen, alkoxy, haloalkoxy, alkyl sulphonyl, haloalkyl sulphonyl, alkylthio, haloalkylthio, etc., and
• Y is hydrogen in the case of 4-equivalent couplers or a substituent which splits off upon colour development thus conferring to the colour coupler a 2-equivalent character e.g. a halogen atom such as chlorine, an acyloxy group, an alkoxy group, an aryloxy group or a heterocycloxy group, an alkylthio group, an arylthio group or a heterocyclic thio group such as tetrazolylthio, a phenylazo group, etc.
• a 2-equivalent character e.g. a halogen atom such as chlorine, an acyloxy group, an alkoxy group, an aryloxy group or a heterocycloxy group, an alkylthio group, an arylthio group or a heterocyclic thio group such as tetrazolylthio, a phenylazo group, etc.
• a residue of a yellow forming colour coupler of the acylacetamide type especially the acylacetanilide type for example an anilino carbonylacetophenyl group or a benzoylacetamidophenyl group wherein both aryl group may be substitutedby substituents well known in yellow-forming colour couplers e.g. alkyl, alkoxy, halogen, alkylthio, alkylsulphonyl, etc. and wherein the active methylene group may carry a substituent conferring to the colour coupler a 2-equivalent character e.g. a halogen atom such as chlorine, acyloxy, an alkoxy, aryloxy or heterocycloxy group, an alkylthio, arylthio or heterocyclic thio group, etc.
• substituents well known in yellow-forming colour couplers e.g. alkyl, alkoxy, halogen, alkylthio, alkylsulphonyl,
• a competing coupler residue e.g. of the type described for the above colour couplers wherein one hydrogen atom of the active methylene group is replaced by alkyl, preferably C -C alkyl including substituted alkyl e.g. benzyl, preferably a competing coupler residue of the 2-pyrazolin-5-one type.
• persulphates such as ammonium and potassium persulphate, azonitrile compounds such as 4,4-azo-bis(4-cyanovaleric acid) as well as peroxide compounds such as benzoyl peroxide, hydrogen peroxide.
• the aqueous dispersion of the polymerisable composition may optionally contain conventional emulsifiers although they can be omitted and, if used, can usually be employed in smaller proportion than is possible with known procedures where no comonomeric emulsifier is used.
• the comonomeric sulphoesters and sulphoamides of acrylic acids and a-substituted acrylic acids are generally used in amounts ranging from about 0.5 to about 15, preferably from about 1 to about 10% by weight relative to the weight of other polymerisable ethylenically unsaturated monomers.
• the latices obtained generally comprise between about 2 and about 50 by weight of polymeric colour coupler or competing coupler in respect of the total amount of latex.
• the polymeric couplers according to the present invention can be. characterized by their so-called equivalent molecular weight.
• equivalent molecular weight is understood the number of grams of polymer containing 1 mole of polymerized monomeric coupler. It can be compared with the molecular weight of the non-polymeric classical non-migratory couplers.
• the equivalent molecular weight of the polymeric couplers according to the invention can vary within very wide limits, preferably from about 200 to about 2000.
• a suspension of 260 ml of demineralized water, 52.5 g of 1-phenyl-3-methacrylamido-4-methyl-2-pyrazolin- 5-one and 37.5 ml of a 10 aqueous solution of the sodium salt of 2-sulphoethylmethacrylate was stirred for 30 min. while introducing nitrogen.
• the suspension was heated to 90C whereupon 6.75 g of n-butylacrylate and 8.5 ml ofa 1 aqueous solution of the sodium salt of 4.4-azo-bis(4-cyanovaleric acid) were added.
• the temperature was raised to the reflux temperature and over a period of 30 min. were added 12 g of n-butylacrylate and 29 ml of a 1 aqueous solution of the above polymerization initiator.
• the mixture was refluxed for 1 hour and the latex obtained was cooled and filtered.
• a suspension of 170 ml of demineralized water 40 g of l-p-methylsulphonylphenyl-3-methacrylamido-4- methyl-2-pyrazolin-5-one, 2.5 g of the sodium salt of 2-sulphoethylmethacrylate and 7.5 g of butylacrylate was heated to 90C whereupon 15 ml of a 1 aqueous solution of the sodium salt of 4,4'-azo-bis(4-cyanovaleric acid) were added. The temperature was raised to the reflux temperature. The mixture was refluxed for 1 hour and the latex obtained was cooled and filtered.
• a mixture of 175 ml of demineralized water, 20 g of l-benzyl-3-methacrylamido-2-pyrazolin-5-one, 10 g of styrene and 2.5 g of the sodium salt of 2-sulphoethyl methacrylate was heated to 90C while introducing nitrogen.
• Nitrogen was introduced into a suspension of 300 ml of demineralized water, 40 g of p-methacrylamidobenzoyl acetaniside (mp 168C) prepared from p-aminobenzoyl acetaniside and methacryloyl chloride, and 50 ml of a 10 aqueous solution of the sodium salt of 2-sulphoethyl methacrylate.
• the mixture was heated to C whereupon 12 g of methacrylic acid and 7 g of butyl acrylate were added.
• the temperature was raised to C and 25 ml of a l aqueous solution of the sodium salt of 4,4'-azo-bis(4cyanovaleric acid) were added.
• Latex of the copolymer of 2-methylsulphonylamino- 5-acrylamidophenol, butylacrylate and the sodium salt of 2-sulphoethyl methacrylate was prepared in the same way as the latex of preparation 6 from 20 g of 2-methyl sulphonylamino-S-acrylamidophenol, 27.5 g of butyl acrylate and 2.5 g of the sodium salt of 2-sulphoethyl methacrylate.
• Nitrogen was introduced for 30 min. into a suspension of 350 ml of demineralized water, 50 g of lhydroxy-4-chloro-N-B-acrylamidoethyl-Z-naphthamide and 5 g of the sodium salt of 2-sulphoethyl methacrylate.
• the mixture was heated to 70C and 15 g of butyl acrylate were added.
• the mixture was further heated to 90C and 15 ml of a l aqueous solution of the sodium salt of 4,4-azo-bis(4-cyanovaleric acid) were added.
• the mixture was refluxed for 10 min. whereupon 30 g of butyl acrylate and 35 ml of the above 1 aqueous solution were added. After 30 min., the latex was cooled and filtered.
• a suspension of 350 ml of distilled water, 40 g of l-phenyl-3-methacrylamido-2-pyrazolin-5-one, and 5 g of the sodium salt of p-sulphophenyl methacrylate was rinsed with nitrogen for 30 min. and then heated to 90C. Then, 25 g of butyl acrylate and 25 ml of a l aqueous solution of the sodium salt of 4,4'-azobis(4- cyanovaleric acid) were added. The mixture was refluxed for 5 min. and 30 g of butyl acrylate and 25 ml of the said 1 aqueous solution were added in 30 min. Refluxing was continued for 30 min. whereupon the latex was filtered.
• Nitrogen was introduced into a suspension of 175 ml of water, 30 g of l-phenyl-3-methacrylamido-2-pyrazolin-S-one, 5 g of butylacrylate and 2.5 g of the sodium salt of N-2-sulphoethyl methacrylamide.
• the mixture was heated to C and 5 ml of a 1 aqueous solution of the sodium salt of 4,4-azo-bis(4-cyanovaleric acid) were added.
• the temperature was raised to the reflux temperature and in 30 min., 12.5 g of butyl acrylate and 20 ml of the initiator solution were added. Refluxing was continued for 30 min. whereupon the latex was partly concentrated by evaporation, cooled and filtered.
• the latices according to the present invention are used in photographic colour elements either in a silver halide emulsion layer or a hydrophilic colloid layer in water-permeable relationship with the said emulsion layer.
• the latices of polymeric colour couplers are preferably incorporated in a silver halide emulsion layer whereas the latices of polymeric competing couplers are preferably incorporated in one or more intermediate hydrophilic colloid layers in water-permeable relationship with the emulsion layers.
• the latices according to the invention In dispersing the latices according to the invention into the hydrophilic colloid composition e.g. an aque ous gelatin solution or a gelatino silver halide emulsion there can be dispensed with the use of an external ballasting emulsifying agent or reduced amounts of emulsifying agents can be used so that it is possible to reduce the thickness of the coated layers which results in increased sharpness.
• the latices according to the invention also produce less foam when incorporated into the hydrophilic colloid coating composition.
• the latices of preparations 3a, 4, 5, 6 and 8 hereinbefore were admixed with a conventional photographic silver halide colour emulsion no supplemental amount of emulsifier was necessary to stabilize the latex polymer in the emulsion.
• the latices corresponding to those of preparations 3a, 4,5,6, and 8 but prepared in the conventional way i.e. in the presence of 5 g of sodium oleyl methyl tauride (OMT) per 100 g of monomers used instead of the sodium salt of 2-sulphoethyl methacrylate, required a supplemental amount of OMT to be stabilised in the emulsion.
• OMT sodium oleyl methyl tauride
• the polymeric couplers of the present invention may be used in various kinds of photographic colour materials which include negative, positive as well as reversal material.
• Photographic multilayer colour materials usually comprise at least one blue-sensitive silver halide emulsion layer with colour coupler for yellow, at least one green-sensitized silver halide emulsion layer with colour coupler for magenta and at least one red-sensitized silver halide emulsion layer with colour coupler for cyan.
• These colour materials may further comprise one or more intermediates layers, filter layers and protective surface layers.
• the hydrophilic colloid used as the vehicle for the silver halide emulsion layer and the other hydrophilic colloid layers may be, for example, gelatin, colloidal albumin, zein, casein, a cellulose derivative, a synthetic hydrophilic colloid such as polyvinyl alcohol, poly-N- vinyl pyrr'olidone, etc., gelatin being preferred. If desired compatible mixtures of two or more of these colloids may be employed.
• the silver halide emulsion layer may comprise various silver halides as the sensitive halide such as silver bromide, silver chloride, silver chlorobromide, silver bromoiodide and silver chlorobromoiodide.
• the photographic colour elements comprising the polymeric couplers of the present invention may comprise as supports paper, glass, cellulose ester film, polyvinylacetal film, polystyrene film, polyethylene terephthalate film and related films of resinous materials.
• aromatic primary amino developing agents are used forming dyestuffs with the polymeric colour couplers of the present invention and colourless compounds with the polymeric competing couplers of the present invention.
• Suitable developing agents are p-phenylene diamine and derivatives e.g.
• EXAMPLE 1 a Comparison material A 109 g of a silver bromoiodide emulsion (2.3 mole of iodide) which comprises per kg an amount of silver halide equivalent to 47 g of silver nitrate and 73.4 g of gelatin, are diluted with 185 g of a 7.5 aqueous solution of gelatin and 100 g of distilled water. To the emulsion obtained are added with stirring 23 ml of the latex prepared according to preparation 6 of British Pat. application No. 59792/60 which corresponds to 0.006 mole of polymerised monomeric colour coupler. After the addition of the common additives such as stabilizers, wetting agents and hardeners the necessary amount of distilled water is added to obtain 575 g.
• common additives such as stabilizers, wetting agents and hardeners
• the materials were rinsed with water for 5 min. and treated for 5 min. at 24C in the above acid hardening fixer.
• EXAMPLE 2 l 17 g of a silver bromoiodide emulsion (2.3 mole of iodide) which comprises per kg an amount of silver halide equivalent to 47 g of silver nitrate and 73.4 g of gelatin, are diluted with 192.5 g of a 7.5 aqueous solution of gelatin and g of distilled water. To the emulsion obtained are added with stirring 12 ml of the latex. prepared according to preparation 3b which corresponds to 0.006 mole of polymerised monomeric colour coupler. After the addition of the common additives such as stabilizers, wetting agents and hardeners the necessary amount of distilled water is added to obtain 720 g.
• the common additives such as stabilizers, wetting agents and hardeners the necessary amount of distilled water is added to obtain 720 g.
• the emulsion obtained is coated on a cellulose triacetate support pro rata of l25 g per sq.m.
• the emulsion layer is dried and overcoated with a: gelatin antistress layer.
• EXAMPLE 3 A material was prepared as described in example 1 with the difference that now 48 ml of the latex prepared according to preparation 5, which corresponds to 0.006 mole of polymerised monomeric colour coupler were added.
• N.N-diethyl-p-phenylene diamine sulphate hydroxylamine sulphate sodium hexametaphosphate anhydrous sodium sulphite anhydrous potassium carbonate potassium bromide water to make The developed material was treated for 2 min. at l820C in an intermediate bath comprising 30 g of sodium sulphate in 1 liter of water.
• the material was rinsed for 15 min. with water and treated in a bleach bath of the following composition:
• a photographic multilayer negative material A was composed as follows:
• a protective gelatin coating For comparison purposes a material Bwas prepared in exactly the same way as material A with the only difference that both the gelatin-intermediate layer and the filter layer comprise per sq.m ,3 ml of the latex of the polymericcompeting coupler according to preparation 2, which corresponds to l millimole of polymerized monomeric coupler.
• the separation images of material B showed purer colours than those of material A.
• a photographic colour element comprising a support and at least one light-sensitive silver halide emulsion layer wherein the element comprises a copolymer latex containing recurring units derived from a first ethylenically unsaturated monomer which will undergo oxidative coupling with an aromatic primary amino compound corresponding to the formula:
• R is hydrogen, C C., alkyl or chlorine, and Q is a moiety which will undergo oxidative coupling with an aromatic primary amino compound, and recurring units derived from a second monomer corresponding to the formula:
• R is hydrogen, C -C alkyl or chlorine
• X is O or N(R) wherein R is hydrogen or lower alkyl
• Y is a divalent hydrocarbon group which may be interrupted by oxygen and/or sulphur
• M is a cation
• a photographic element according to claim 1, wherein the polymer comprises recurring units of additional ethylenically unsaturated monomers which are not capable of oxidative coupling with aromatic primary amino compounds.
• a photographic element according to claim 5, wherein the said additional monomers are one or more members selected from the group consisting of acrylic 16 colour coupler and is present in a light-sensitive silver halide emulsion layer.
• a photographic element according to claim 1, wherein the said polymeric compound is a polymeric competing coupler and is present in an intermediate non-light-sensitive water-permeable colloid layer of the photographic element.

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• 1973
  • 1973-02-26 GB GB942173A patent/GB1453057A/en not_active Expired
• 1974
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