| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject composition excellent in extreme-pressure property, lubricating property and processability by compounding a specific polyester with zinc dithiophosphate. SOLUTION: This metal working fluid composition comprises (A) a polyester obtained by condensing (i) a dimer acid (preferably, a dimer acid produced from 18C unsaturated fatty acid such as oleic acid) with (ii) a neopentyl type polyol (preferably neopentyl glycol) or a polyester obtained by condensing the component (i) with the component (ii) and an alcohol or phenol and (B) a zinc dithiophosphate of formula I (R1 to R<4> are each hydrocarbon). The composition contains preferably 30-70wt.% component A and preferably 30-60 component B. The molecular weight of the component A is 2000-30000. In the case when further severer metal working conditions are required, the composition is preferably compounded with oxysulfide molybdenum dithiocarbamate, etc., of formula II [R<5> to R<8> are each a hydrocarbon; X<1> to X<4> are each 0 or S]. |
