Patent ID: 7833951

Claim:
A water-soluble metal working lubricant comprising 60 mass % or less of water (A): 10 to 50 mass % of a metal salt of an organic carboxylic acid (B) wherein the carboxylic acid residue has 8 or more carbon atoms in total and the acid/alkali ratio by mole is 10.6 to 1.0; 4 to 40 mass % of at least one metal salt (C) selected from among an organic phosphate ester metal salt having an alkyl group having 8 or more carbon atoms in total, wherein the organic phosphate ester metal salt is represented by formula (1) or (2) R 1 O(R 2 O)P(═O)OMe (1) R 3 OP(═O)(OMe) 2 (2) wherein each of R 1 and R 2 represents an alkyl group having 8 or more carbon atoms in total; R 3 represents an alkyl group having 8 or more carbon atoms; and Me represents a metal element, 15 to 70 mass % of an non-ionic surfactant (D).