| 摘要 |
PURPOSE:To improve shelf stability of the title compound useful as a bleaching agent for photography by adjusting an aqueous solution of iron (III) 1,3- propylenediamine tetraacetate to a specific pH and suppressing reduction to iron (II) salt during storage. CONSTITUTION:In adjusting an aqueous solution of iron (III) 1,3propylenediamine tetraacetate to pH3-6.5, more preferably to pH 4.0-6.0 and preserving the aqueous solution at room temperature-in heated state, reductiom to iron (II) salt is suppressed. In order to adjust pH, ammonia water, alkali metal carbonate or hydroxide may be most generally used. When the aqueous solution is adjusted to the pH range, the aqueous solution can be supplied in a stable state of aqueous solution without exerting bad influence on characteristic bleaching action as a bleaching agent for photography (bleaching fixing agent). |
