| 摘要 |
PURPOSE:To obtain a color developing solution improved in long-term storage stability, by adding aminotris(methylenephosphonic acid) and 1-hydroxyalkylidene-1,1-diphosphonic acid to a color developing agent. CONSTITUTION:A color developing solution contains aminotris(methylenephosphonic acid) or at least one of its salt represented by formulaI, M being H, an alkali metal, or ammonium, and at least one of 1-hydroxy-alkylidene-1,1-diphosphonic acid represented by formula II, R being 1-5C alkyl. A preferable addition amount of compound or its salt of formulaIis 0.01-10g/l of color developing solution, and that of compound of formula II is 0.1-10g. A known heavy metal sequestering agent can be used together with said compounds. |
