To provide a new cooling liquid composed of a glycol, a polyglycol or a glycerol and free from silicate and effective for improving the light metal corrosion protecting performance of existing silicate-free heat-transfer liquid.
The concentrated liquid of a cooling agent or concentrated liquid of an antifreezing agent contains (a) 0.05-5 wt.% one or more carbamates expressed by formula (X is O or S; and R is a 1-8C alkyl or a 6-18C aryl) or their ammonium salts, (b) 0.05-4 wt.% tricarboxylic acid and/or triazine triiminocarboxylic acid, (c) 0.05-8 wt.% 4-16C monocarboxylic acid and/or dicarboxylic acid in the form of an alkali metal salt or ammonium salt, (d) 0.01-2 wt.% hydrocarbon-triazole or hydrocarbon-thiazole, (e) 0.01-2 wt.% water-soluble alkali metal salt and/or alkaline earth metal salt and (f) 80-99 wt.% ethylene glycol, polyglycol or glycerol.
STANKOWIAK ACHIM
Tsuneo Mihara
Okumura Yoshimichi
Blacksmith
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