Patent ID: 7956226

Claim:
A traction drive fluid composition which comprises component (A) a base oil for traction drives selected from hydrogenated products of the dimers of at least one alicyclic compound selected from among bicyclo [2, 2, 1]heptane ring-bearing compounds, bicyclo [3, 2, 1] octane ring-bearing compounds, bicyclo [2 2, 2] octane ring-bearing compounds, and bicyclo [3, 3, 0] octane ring-bearing compounds; and from cyclohexane ring-bearing compounds selected from the group consisting of 2,4-dicyclohexyl-2-methylpentane, 2,4-dicyclohexylpentane, 2,4-dicyclohexyl-2-methylbutane, and 1-decahydronaphthyl-1-cyclohexylethane and component (B) at least one polymer having a weight average molecular weight in the range of 8,000 to 40,000 and which is selected from the group consisting of (a) hydrocarbon polymers each comprising as a constituent at least 10 mole % of a monomer bearing a cyclic structure and (c) hydrogenated products from the polymers (a); wherein each of the hydrocarbon polymers (a) is a polymer of a monomer bearing a cyclic structure, or a copolymer of a monomer bearing a cyclic structure and an aliphatic monomer selected from the group consisting of ethylene, propylene, butene, pentene, hexene, heptene, octane, nonene and decene; wherein the monomer bearing a cyclic structure is selected from the group consisting of styrene, vinylnaphthalene, indene, vinylcyclohexane, vinylcyclohexene, cyclohexene, dipentene, limonene, bicyclo [2,1,1] heptene, methylbicyclo [2,2,1] heptene, dimethylbicyclo [2,2,1] heptene, dicyclopentadiene, dihydrodicyclopentadiene, and tetracyclo [6.2.1.1 3.6 0 2.7 ]dodecene; and wherein a blending ratio of the component (B) is 0.5 to 5% by mass based on the composition.