Patent ID: 6255546
Filing Date: 2001-07-03
Classification: C10M,C10N

Abstract:
A functional fluid comprising(A) a mixture of at least two hydrocracked base stocks, said mixture comprising(i) at least one first hydrocracked base having a kinematic viscosity of about 3.5 to about 6.5 mm.sup.2 /sec at 100.degree. C., a viscosity index of about 100 to about 120, a pour point of about -12.degree. C. maximum, an aniline point of about 100 to about 120.degree. C., a saturates content of about 92 to about 99 mass %;(ii) at least one second hydrocracked base stock having a kinematic viscosity of about 1.5 to about 3.5 mm.sup.2 /sec at 100.degree. C., a viscosity index of about 90 or higher, a pour point of about -30.degree. C. maximum, an aniline point of about 95.degree. C. to about 110.degree. C., a saturates content of about 90 to about 99 mass %;said first and second hydrocracked base stocks being mixed in an amount of about 60 to about 90 vol % of the first hydrocracked base stock (i) and about 10% to about 40% of the second hydrocracked base stock (ii), based on the hydrocracked stock;wherein the first hydrocracked base stock (i) and second hydrocracked base stock (ii) are not the same; and(B) zero up to about 45 vol % of one or more conventional solvent neutral base stock(s), the conventional solvent neutral base stock having a kinematic viscosity of about 2.5 to about 5.5 mm.sup.2 /sec at 100.degree. C., a viscosity index of about 90 to about 105, a pour point of about -12.degree. C. maximum, an aniline point of about 95 to about 105.degree. C., a saturates content of about 75 to about 85 mass %; whereinsaid mixture of base stocks has a kinematic viscosity of about 3.7 to about 5 mm.sup.2 /sec at 100.degree. C., a viscosity index of about 100 to about 115, a pour point of about -24.degree. C. maximum;(C) an additive package, the resulting additized functional fluid having a kinematic viscosity of about 6.8 to about 8.0 mm.sup.2 /sec at 100.degree. C., a viscosity index of 150 to about 200, a pour point of about <-42.degree. C. maximum, and a Brookfield viscosity of about 15,000 cP or less at -40.degree. C.