Ilford Limited

Ross Fielding

Robert S Millington

There is described a fixing bath for developed silver halide photographic material which comprises as the active silver halide solvent a combination of sodium thiosulphate and potassium thiosulphate, the molar ratio of sodium to potassium being from about 2:3 to about 3:2.

Fixing bath

There is described a concentrated developer solution which comprises from about 20 to about 60 g/l of dihydroxybenzene developing agent, preferably hydroquinone, from about 0.5 to about 3.0 g/l of an auxiliary developing agent, preferably 1-phenyl-3 pyrazolidinone, from about 300 to about 500 g/l of potassium sulphite and which is buffered to a pH of from about 8 to about 10 with a buffering agent other than an alkanolamine and which comprises sufficient organic solvent other than an alkanolamine to dissolve the hydroquinone. Such a concentrated developing solution which contains a high concentration of potassium sulphite has when diluted a long useful life and produces images of low graininess.

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Knutsford Cheshire, United Kingdom

Ross Fielding