| 摘要 |
PURPOSE:To control reducing velocity, by adding a specified heterocyclic compound to a reducing solution using a ceric salt. CONSTITUTION:A heterocyclic compound represented by the general formula in which Q is an atomic group required for forming a heterocyclic ring and R is aklyl, aryl, or a heterocyclic group, and a ceric salt are contained in a reducing solution. The heterocyclic ring to be used is such as benzothiazoline-2-thione, 4,5-tetramethyl- enethiazoline-2-thione, naphthothiazoline-2-thion, thiazolidine-2-thione, imidazolidine-2-thione, selenazolidine-2-thione, or the like. Since mercapto compounds each containing a heterocyclic ring are made remarkably lower in solubility by the low pH of the ceric salt-containing reducing solution, said compound is used, and it is applied to other kinds of reducing solutions. |
