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
  • G03C1/00—Photosensitive materials
  • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
  • G03C1/06—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein with non-macromolecular additives
  • G03C1/34—Fog-inhibitors; Stabilisers; Agents inhibiting latent image regression
• • 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
  • G03C1/00—Photosensitive materials
  • G03C1/005—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein
  • G03C1/035—Silver halide emulsions; Preparation thereof; Physical treatment thereof; Incorporation of additives therein characterised by the crystal form or composition, e.g. mixed grain
• • 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
• • 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
  • G03C7/3022—Materials with specific emulsion characteristics, e.g. thickness of the layers, silver content, shape of AgX grains
• • 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
  • G03C7/392—Additives
  • G03C7/39208—Organic compounds
  • G03C7/39212—Carbocyclic
  • G03C7/39216—Carbocyclic with OH groups

Definitions

• This invention relates to photographic silver chloride emulsions having improved keeping properties.
• Photographic silver chloride emulsions are now widely used in the manufacture of photographic colour negative paper materials. As such materials age their sensitometric performance changes such that the speed and minimum density (D min ) increase while their contrast decreases.
• Known techniques for countering these defects in silver halide emulsions in general include the method described in British Specification 1 262 127 which comprises the addition of small quantities of reducing agents such as amino- hexose-reductones. Control of the emulsion pH and pAg can also be beneficial.
• Blocked bis-phenols have been described as photographic dye image stabilisers in European Patent specification 0 246 766 (US Patent 4 782 011). Specifically the compounds were incorporated into silver chlorobromide emulsions.
• a method for improving the keeping properties of a silver chloride emulsion comprising at least 90% silver chloride which comprises incorporating therein a bisphenol derivative having two linked phenol rings wherein the hydrogen atom of one of the phenolic hydroxy groups is replaced by a blocking group which is a substituent other than hydrogen and at least one of the phenol rings is substituted.
• the blocking group may be any group which does not affect the desired properties of the stabilizer.
• the two phenol rings of the stabilizer may be linked directly by a single bond or indirectly by a linking group.
• the link between the phenol rings is ortho relative to the phenolic hydroxy group of one ring and the blocked phenolic hydroxy group of the other ring.
• each phenol ring independently is substituted in a position ortho or para relative to the unblocked or blocked phenolic hydroxy groups. It is further preferred that substituents are present in both ortho and para positions.
• the bis-phenol compound preferably has the general formula: wherein R is alkyl, cycloalkyl, alkenyl, aryl, acyl, alkylsuphonyl or arylsulphonyl, R1 is a single bond or a linking group selected from alkylene, alkylidene, a heteroatom or sulphonyl, and each R2 independently represents one or more substituents each selected from alkyl, alkoxy, alkenyl, cycloalkyl, aryl or aryloxy or, each R independently represents the atoms necessary to complete with the benzene ring to which it is attached, a fused polycyclic aromatic ring structure. all of said alkyl, alkoxy, cycloalkyl, alkylene, alkenyl, aryl, aryloxy and acyl groups being optionally substituted.
• blocking group R examples are methyl, ethyl, propyl or butyl, cyclohexyl, phenyl, acetyl or benzoyl.
• linking group R1 examples are methylene, butylidene, 3,5,5,-trimethylhexylidene, oxygen, sulphur or sulphonyl.
• An especially preferred group of bis-phenol compounds has the general formula: wherein R1 and R are as defined above, and R3, R4, R5 and R6 are each independently a substituted or unsubstituted alkyl, alkenyl, cycloalkyl or aryl group.
• R3 and R4 are identical and R5 and R6 are identical.
• the blocked bisphenol derivatives are readily prepared from their unblocked counterparts, many of which are commercially available.
• a blocking group may be introduced into the unblocked parent bisphenol by reaction with an appropriate reactive halogen-containing compound e.g. an alkyl bromide, acyl chloride, sulphonyl chloride or a dialkyl sulphate e.g. diethyl sulphate.
• unblocked parent bisphenols from which the stabilizers of the present invention may be prepared are as follows:
• the present invention also provides a method for improving the keeping properties of a silver chloride emulsion comprising the incorporation therein of a bisphenol derivative having two linked phenol rings wherein the hydrogen atom of one of the phenolic hydroxy groups is replaced by a blocking group which is a substituent other than hydrogen and at least one of the phenol rings is substituted.
• the silver chloride emulsions used in the present invention contain more than 90 mole %, silver chloride preferably the emulsions are substantially pure silver chloride.
• the bis-phenol compounds may be incorporated in the silver chloride emulsions as a dispersion of droplets of a high boiling coupler solvent containing the bis-phenol. Such droplets may also contain a colour coupler. Alternatively they may be incorporated as solutions in an alcohol, for example, methanol.
• the colour coupler may be of any class of couplers useful in colour photographic materials.
• coupler classes include phenolic and naphtholic cyan couplers, pyrazolidone and pyrazolotriazole magenta couplers and acylacetanilide yellow couplers.
• Such couplers preferably have the general formula: wherein R7 represents one or more substituents of the type found in such couplers, and R8 is a coupling-off group, preferably an aryloxy group.
• Suitable emulsions, emulsion additives and couplers for use in the emulsions and elements of this invention are described in Research Disclosure, December 1978, Item 17643, published by Kenneth Mason Publications Ltd., 12a North Street, Emsworth, Hants PO10 7DQ, U.K. In particular, information on couplers and on methods for their dispersions are given in Sections VII and XIV, respectively, of this article.
• Each dispersion was mixed with a blue-sensitive silver chloride emulsion and coated on a resin-coated paper support, such that the silver and coupler coverages were, respectively, 0.18 g/m2 and 0.40 g/m2.
• Strips of the fresh coatings were exposed and processed through RA4 chemistry to assess sensitometric performance. Further strips were incubated in the dark for 1 week at 50 °C and 50% RH before being similarly exposed and processed.
• the Table below shows figures for the D min and contrast of the freshly coated and incubated strips from each coating.
• the columns labelled " ⁇ " show the difference between the fresh and incubated samples. Taking the coating without any addendum as a reference, the two blocked bis-phenols reduced the extent of D min increase and the loss in contrast due to incubation. A contrary effect was shown by the comparison bis-phosphate ester.
• Dispersions of each coupler alone were also made.
• the coupler was dissolved in its own weight of ethyl acetate and one half its weight of dibutyl phthalate. When present the bisphenol was included at half the weight of the coupler.
• the oil solutions were dispersed in aqueous gelatin using ultrasonic agitation as in Example 1.
• Each dispersion containing Coupler (B) was mixed with a red-sensitised silver chloride emulsion and coated on a resin-coated paper support, such that the silver and coupler coverages were, respectively, 239 mg/m2 and 425 mg/m2.
• a second pair of coatings was made from the dispersions at the same component coverages but utilising a blue-sensitised emulsion (as used in Example 1) in place of the red sensitised emulsion.
• Coupler (C) the dispersions of Coupler (C) were coated together with a green sensitised silver chloride emulsion at silver and coupler coverages of 285 mg/m2 and 447 mg/m2 respectively.
• Sample strips of the fresh coatings were exposed and processed through RA4 chemistry to assess sensitometric performance. Another strip from each coating was incubated in the dark for 8 days at 50°C and 50% RH before being exposed and processed.

Landscapes

• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Spectroscopy & Molecular Physics (AREA)
• Crystallography & Structural Chemistry (AREA)
• Silver Salt Photography Or Processing Solution Therefor (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=10669458

Family Applications (1)

Country Status (5)

Citations (1)

Family Cites Families (1)

• 1990
  • 1990-01-17 GB GB909001078A patent/GB9001078D0/en active Pending
• 1991
  • 1991-01-12 JP JP50223492A patent/JPH04506579A/ja active Pending
  • 1991-01-12 WO PCT/EP1991/000069 patent/WO1991010938A1/en active IP Right Grant
  • 1991-01-12 DE DE69115767T patent/DE69115767T2/de not_active Expired - Fee Related
  • 1991-01-12 EP EP91901765A patent/EP0463136B1/en not_active Expired - Lifetime

Patent Citations (1)

Also Published As

Similar Documents

Legal Events