Patent GB-714012-A (GB)
Title: Photographic colour correction processes
IPC: G03C7/18
Filed: 1952-07-23
Abstract: The polyvinyl acetal of 3-(carbo-p-cresoxyamino)-benzaldehyde, containing methylidenephenyl-o-sulphonate groups for increased solubility, is prepared by adding phosphoric acid to a solution of polyvinyl alcohol and sodium benzaldehyde-o-sulphonate in ethylene glycol and stirring, adding a dioxane solution of 3-(carbo-p-cresoxyamino)-benzaldehyde ethylene glycol acetal thereto and stirring, adding a methanol solution of triethylamine to neutralize the phosphoric acid, and precipitating with acetone.  The polyvinyl acetal of 3-aminobenzaldehyde containing sodium methylidene phenyl-o-sulphonate is prepared either by hydrolyzing an aqueous ethanol solution of the above polyvinyl acetal with aqueous sodium hydroxide solution, or by stirring a mixture of polyvinyl alcohol, sodium benzaldehyde-o-sulphonate, ethylene glycol, phosphoric acid, and phosphoric anhydride, adding an ethylene glycol solution of m-aminobenzaldehyde ethylene glycol acetal and continuing stirring, and isolating as before.  The polyvinyl acetals of 3-(carbo-p-cresoxyamino)-4-methoxybenzaldehyde, of 3-amino-4-methoxybenzaldehyde, of m-(5-carbethoxyamino-2-chlorobenzamido)-benzaldehyde, of m-(5-carbo-methoxyamino - 2 - chlorobenzamido) - benzaldehyde, of m-(5-carbo-p-cresoxyamino-2-chlorobenzamido)-benzaldehyde, and of m-(5-amino-2-chlorobenzamido)-benzaldehyde, all containing methylidenephenyl-o-sulphonate groups, are similarly prepared. Specifications 458,400, [Group XX], 469,108, 598,477, 600,023, 602,881, [Group XX], 627,125, 631,269, [Group IV (b)], 635,294, 638,895, 641,368, [Group XX], 652,928, and 662,793 are referred to.ALSO:3 - Nitro - 5 - stearamidobenzoic acid is prepared by heating together 3-nitro-5-aminobenzoic acid, stearoyl chloride, and pyridine.  3 - Amino - 5 - stearamidobenzoic acid is prepared by reducing 3-nitro-5-stearamidobenzoic acid in ethanol with hydrogen under pressure in the presence of palladium - on - charcoal catalyst. 3 - (Carbo - p - cresoxyamino) - benzaldehyde ethylene glycol acetal is prepared by adding p-cresyl chloroformate to a mixture of an acetone solution of m-aminobenzaldehyde ethylene glycol acetal and aqueous sodium carbonate.  3 - (Carbo - p - cresoxyamino) - 4 - methoxy - benzaldehyde ethylene glycol acetal is similarly prepared. M - (5 - Carbethoxyamino - 2 - chlorobenzamido)-benzaldehyde ethylene glycol acetal is prepared by adding a dioxane solution of 5-carbethoxyamino-2-chlorobenzoyl chloride to a mixture of a dioxane solution of m-aminobenzaldehyde ethylene glycol acetal and aqueous sodium carbonate.  M-(5-Carbomethoxyamino - 2 - chlorobenzamido) - and m - (5-carbo - p - cresoxyamino - 2 - chlorobenzamido)-ethylene glycol acetals are similarly prepared.  5 - Carbethoxyamino - 2 - chlorobenzoyl chloride is obtained by reacting 5-carbethoxyamino-2-chlorobenzoic acid with thionyl chloride.  5 - Carbethoxyamino - 2 - chlorobenzoic acid is prepared by adding ethyl chloroformate to an aqueous solution of 2-chloro-5-aminobenzoic acid containing sodium carbonate. Specifications 458,400, [Group XX], 469,108, 598,477, 600,023, [Group IV (a)], 602,881, [Group XX], 627,125, 631,269, 635,294, 638,895, 641,368, [Group XX], 652,928, and 662,793, [Group IV (a)], are referred to.