Photographic reversal composition and method of use
AssigneeEastman Kodak Company
InventorsJohn S. Badger, Mary E. Craver
Life of this patent
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Abstract
Color reversal photographic films are processed using a reversal solution comprising stannous ion and a quaternary ammonium compound as the sole microbial control agent, to reduce formation of visible biogrowth. The quaternary ammonium compound is present at very low concentrations of 1 to 20 ppm, and is preferably myristyltrimethyl ammonium bromide because it avoids precipitates with components that may leach out of some processed films.
Claims9
A precipitate-free photographic reversal composition comprising stannous ion at a concentration of from about 0.002 to about 0.02 mol/l, at least 0.1 mg/l of p-aminophenol as a stannous ion stabilizer, and myristyltrimethyl ammonium bromide as the sole microbial control agent at a concentration of from about 5 to about 10 ppm.
A photographic reversal composition having a pH of from about 4 to about 7 and comprising:
- a) stannous ion at a concentration of from about 0.004 to about 0.01 mol/l,
- b) a quaternary ammonium compound as the sole microbial control agent at a concentration of from about 5 to about 10 ppm, said quaternary ammonium compound being myristyltrimethyl ammonium bromide,
- c) at least 0.1 mg/l of p-aminophenol as a stannous ion stabilizer, and
- d) an organic phosphonic or phosphinic acid chelating agent.
Dependencies are inferred from the claim text.