Gaf Corporation

Felix Viro

Salvatore Emmi

Burton H Waxman

Theodore Panasik

Michael C Mourning

Robert T Shannahan

Hydrophilic coupler-oil solutions are stabilized by the addition of an epoxide compound. These coupler compounds are dissolved, with the aid of epoxide compounds, in high boiling esters and dispersed in aqueous gel solutions to form dispersions of improved stability.

Hydrophilic color coupler composition containing diepoxide

A diffusion transfer photographic element containing a lipophilic, non-diffusing color former in a silver halide emulsion layer, or in a layer adjacent thereto, is developed by using a water- and alkali-soluble color developer capable of coupling with the color former to form a diffusible coupled product, the color developer being coated with the silver halide emulsion layer or in any layer of the photographic element or being in an alkaline developing solution.

Color developer for diffusion transfer

Lipophilic non-diffusing color formers yielding diffusing dyes are employed in color transfer systems to provide improved diffusion and better quality of color. The color formers are two-equivalent couplers having in the coupling position acyloxy, or sulfonyloxy groups which complete a lactone or sultone ring, respectively, and are stable to hydrolysis under alkaline development conditions. Color-providing material is created by a reaction which opens the lactone or sultone intramolecular ring after the non-diffusing color former reacts with the oxidized color developer molecule. Examples are given of intramolecular 2-equivalent couplers which react with the developer to give yellow, magenta and cyan dyes. The 2-equivalent color formers are unique since they have an intramolecular lactone or sultone ring which opens under oxidative coupling conditions to yield the diffusible yellow, magenta and cyan dyes.

Diffusion transfer color process using lactone or sultone ring

Hydrophilic coupler solutions are improved by the addition of a diepoxide, pyruvaldehyde, ethyleneglycoldiglycidyl ether or 2,3-butanedione. These solutions exhibit greater stability and a reduced rate of viscosity increase when admixed into gelatin silver halide emulsions.

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Apalachin, NY, United States of America

Felix Viro