GB1502458A - Method for preparation of a developer in the form of a unique composition for processing black-and-white cinematographic and photographic materials - Google Patents

Abstract

1502458 Photographic developer FABRIKA KHIMFOTO 5 July 1975 28420/75 Heading G2C A photographic developer is prepared by the steps of (a) treating photographic developing substances with a solution containing sugar, sodium sulphite, boric acid and aniline dye in distilled water, (b) adding to the resulting mixture a preservative, accelerating and fogging agents, and (c) drying the resulting composition to obtain a dry powder, the developing substances being N-methyl-p-aminophenol sulphate and hydroquinone, or hydroquinone and 1-phenyl-3-pyrazolidone or hydroquinone and 1-phenyl-4-methyl-3-pyrazolidone, the preservative agent being sodium sulphite, sodium or potassium metabisulphite, the accelerating agent being borax and the anti-fogging agent potassium bromide. Sodium sulphate and boric acid may also be added. The resulting dry powder can be tabletted. 1502470 Thermally developable materials FUJI PHOTO FILM CO Ltd 24 Dec 1975 [28 Dec 1974] 52864/75 Heading G2C A thermally developable light-sensitive photographic material comprises a support having therein or theron at least one layer comprising (a) an organic silver salt, (b) a light-sensitive silver halide or a halogen compound capable of forming a lightsensitive silver halide by reaction with the organic silver salt, and (c) a reducing agent, the support further having therein or thereon a layer containing at least one thiosulphonate or thiosulphonic acid. The latter compound reduces generation of heat fog and loss of sensitivity during storage. The material also optionally contains a benzotriazole. Suitable thiosulphonic acid compounds are of the formula RSO2 SM where R is a substituted or unsubstituted alkyl or aryl group and M is a cation other than hydrogen. Suitable benzotriazoles are of the Formula wherein R1 represents hydroxy, alkoxy, halogen or acyl, R2 to R5 each represents alkyl, substituted alkyl, halogen or nitro. They can be used in combination with mercury compounds and N-halogen compounds, thiouracils. It is also preferred to use in combination the thiosolfonic compounds and higher fatty acids (e.g. as Li salts) and rosin or diterpenic acid. Salts e.g., Nickel nitrate, rhodium triammonate and cobalt acetyl-acetonate can be added. A vaccum-deposited metal layer, e.g. of Sn, Ag, Fe, Ni can be applied to the opposite surface of the support. Lists are given of halogenating compounds reducing agents (which may be light-decomposable, toning agents), development acceleration (e.g. Sn, Fe, Co or Ni compounds) that can be incorporated.