Patent ID: 8389451

Claim:
A method for improving the air release rate of a lubricant composition comprising a major amount of a lubricating base oil and which composition is substantially free of a viscoelastic fluid having both a shear stress greater than 11 kPa and a kinematic viscosity greater than 30 cSt at 100° C., the method comprising adding to the lubricating base oil greater than about 5 wt % of a combination of vinylaromatic-olefin block copolymers that forms a micelle-like structure in the base oil; wherein the vinylaromatic-olefin block copolymer combination is a combination of a linear styrene-diene copolymer in which diene has from 4 to about 10 carbon atoms and of a divinylbenzene-isoprene star copolymer; and wherein the linear styrene-diene copolymer and divinylbenzene-isoprene star copolymer are in a weight ratio of from 1:3 to 3:1 respectively.