| 摘要 |
PURPOSE:To provide an antifreezing agent in the form of a compsn. contg. no amines and having excellent corrosion-proofing properties especially for aluminum, by adding a combination of specific compds. to an antifreezing agent composed of a glycol and water and adjusting the pH of the resulting mixture in a limited range. CONSTITUTION:The following compds. A-F are added to an antifreezing agent composed of a glycol and water, and the pH of the resulting mixture is adjusted in the range of 6.5-9.0. Said compds. are a phosphoric acid (A), a manganese compd. (B), sodium mercaptobenzothiazol (C), a salt of nitric acid (D), a salt of benzoic acid (E), and a dicarboxylic acid (F). As an alkaline substance to be used for pH adjustment, use is pref. made of a hydroxide of an alkali metal such as lithium, sodium or potassium. |
