Replacement of sulfites and tribasic sodium phosphate in photographic formulas

A combination of an alkali metal metabisulfite and an alkali metal hydroxide may be used in lieu of sulfite, such as:


a) a combination of 0.702 gram of potassium metabisulfite plus 0.355 gram of potassium hydroxide is equivalent to and can replace 1 gram of potassium sulfite.


b) a combination of 0.754 gram of sodium metabisulfite plus 0.317 gram of sodium hydroxide is equivalent to and can replace 1 gram of sodium sulfite.


Such combinations are useful if a sulfite is unavailable,...

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