ALKYLTHIOPHOSPHATE SALTS FOR LUBRICATING OILS

摘要

There are disclosed antioxidant additives for lubricating oils which exhibit reduced phosphorus volatility, the additives being sodium, potassium, lithium or oil soluble amine salts of a dialkyldithiophosphoric acid prepared by reacting P2S5 with a mixture of alcohols consisting of (a) a polyol of the formula R(OH)n where R is a C2-C20 hydrocarbyl group and n is 2-10 and (b) an aliphatic monohydric alcohol having 3-18 carbon atoms, the mixture containing relative amounts of polyol and monohydric alcohol such that 50 mole % of the total OH groups are OH groups of the polyol.