Patent GB-663564-A (GB)
Title: Improvements in and relating to the production of colour photographic images
Inventor: MERCK PHILIBERT LEOPOLD JOSEPH
IPC: G03C7/327
Filed: 1948-11-26
Abstract: 663,564. Photographic colour development. GEVAERT PHOTO-PRODUCTEN N.V. Nov. 28, 1949 [Nov. 26, 1948], No. 30721/48. Class 98 (ii). A coloured photographic image is produced by developing a reducible silver salt image with an aromatic amino developing agent in a photographic element containing a polymeric compound or a polycondensation product having in its molecule one or more dye intermediate nuclei, in the average proportion of the order of 10 mol. of nuclei for 1 kg. of polymeric or polycondensation product, corresponding to the formula shown in Fig. IV, wherein the free bond is the point of attachment to. the polymeric or polycondensation product and wherein R<SP>1</SP> is H or a substituent split off during development, Z is an organic radical and X is an electronegative radical. The light-sensitive silver salt may be dispersed in the polymeric or polycondensation coupling compound, or may be dispersed in a polymeric or polycondensation product to which a dye intermediate is subsequently connected. The polymeric or polycondensation coupling compound may also be used to form a non-sensitive layer either immediately adjacent to the emulsion layer or separated therefrom by a water-permeable colloid layer. The coupling compound may be obtained by condensing a coupler having two reactive methylene groups or one reactive methylene group and an amino substituent with an aldehyde or compound reacting as an aldehyde, by condensing a coupler having two reactive methylene groups with sulphur chloride, by linking dye intermediate nuclei to a synthetic linear polyamide containing a plurality of interlinear or side chain solubilizing groups (e.g. ether, hydroxy, carboxylic, or sulphonic groups) to a protein, to a high molecular weight compound containing primary or secondary amino groups (e.g. polyethylene imine), to a partial cellulose derivative or another carbohydrate, to a carbohydrate containing amino groups, to a vinyl alcohol polymer or interpolymer such as a wholly or partially hydrolysed aliphatic terminally unsaturated monoolefine-vinyl ester interpolymer, to a high molecular weight compound containing hydroxyl groups, to a natural resin, to an alkylene oxide polymer, or to a polymeric quaternary ammonium salt having a quaternary nitrogen atom in the recurring units. A high molecular weight compound containing one or more amino, amido, or hydroxy groups may be condensed (a) with a compound according to Fig. IV, wherein the CR<SP>1</SP> group is replaced by a CH 2  group and an aldehyde or a compound reacting as an aldehyde; (b) with a compound corresponding to Fig. IV wherein the CR<SP>1</SP> group is replaced by a CRR<SP>1</SP> group, R being halogen, halogenoalkyl, hydroxyalkyl, an acidic group, or an ester group; or (c) with a carboxylic or sulphonic acid or derivative thereof with a reactive group (e.g. an OH group) which may be replaced by a dye intermediate nucleus of the formula of Fig. IV or an amino group which may be reacted with a dye intermediate of the formula of Fig. IV wherein the group CR<SP>1</SP> is replaced by a CRR<SP>1</SP> group wherein R is halogen. High molecular weight compounds containing one or more OH groups may be (d) condensed with di-(chloromethyl)-ether and a compound of the formula of Fig. IV wherein the group CR<SP>1</SP> is replaced by a CR<SP>1</SP>Na group, or (e) converted into the nitrobenzyl ether derivative, which is reduced to the aminobenzyl ether derivative and then condensed with a compound as in (b) above. A compound of the formula of Fig. IV wherein the group CR<SP>1</SP> is replaced by a CH 2  group or by a CRR<SP>1</SP> group wherein R is hydroxyalkyl or halogenoalkyl, may be reacted with a methylol compound or formaldehyde or a formaldehydeyielding substance and a high molecular weight compound containing one or more amino, amido, or hydroxy groups. In an example, polyvinyl alcohol is mixed with dioxane, aqueous phosphoric acid, and o-sulphobenzaldehyde and heated, 3-methyl-5-acetonyl- 1:2: 4-oxodiazole and paraformaldehyde are added, and heating is continued. Sodium dodecyl sulphate solution and aqueous ammonia are added to an aqueous ethanol solution of the high molecular weight coupler, aqueous solutions of silver nitrate and of ammonium bromide and potassium iodide are added while the temperature is maintained at 45‹ C., the silver halide emulsion. obtained is precipitated with acetone, the precipitate is washed, more high molecular weight coupler is added, and then ethanol and aqueous potassium bromide, and after stirring at 58‹ C. the emulsion is coated on a film support. The material may then be exposed, colour developed, and silver removed. Specifications 483,000, 484,698, 489,274, 537,256, 540,760, 562,675, 577,679, 591,693, 598,367, 598,475, 598,476, 598,479, 618,352, 638,039, 645,043, 648,907 and 663,550 are referred to.