LUBRICATING OIL FOR INTERNAL COMBUSTION ENGINES Russian patent published in 1995 - IPC

FIELD: lubricating oils. SUBSTANCE: lubricating composition for internal combustion engines contains, mas. component B 0.1-15; component D 0.01-2.0; basic salt of alkali metal of sulfonic or carboxylic acid 0.01-2.0; the balance, mineral oil or oil with additives. Components B is product of reaction of one equivalent of polyisobutylene-succinic acid containing 1.3-4 groups of succinic acid per mass of polyisobutylene with 1-2 mole equivalents of alkylene polyamine. Polyisobutylene has average molecular mass of 1300-5000 and weighted mean molecular mass-to-average molecular mass ratio is 1.5-4.5. Component D is salt of dialkyl-dithiophosphoric acid in which one alkyl is isopropyl or secondary butyl, and the other alkyl contains 5-13 atoms of carbon content of isopropyl or secondary butyl groups of 10-80 mas. and metal is in form of calcium, zinc, magnesium, manganese, aluminum, tin, cobalt, nickel, iron, lead, molybdenum or copper. EFFECT: higher efficiency. 3 tbl