Patent · US Active

Lubricant additive compositions having improved viscosity index increase properties

US8778857B2 · kind B2 · utility

5Cited by
77References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 6, 2009
Grant dateJul 15, 2014
Priority date—
Expiry dateSep 16, 2030

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC10N2070/02
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A lubricant composition, additive concentrate, and method for lubricating an engine. The crankcase lubricant has less than 30 weight percent of a relatively low Noack volatility base oil and a viscosity additive. The viscosity additive has a minor effective amount of sacrificial polymeric viscosity index improver having a shear stability index (SSI) of greater than about 45 and a major amount of a viscosity index improver having an SSI of less than about 26. The minor amount of sacrificial viscosity index improver additive is effective to provide a lubricant composition having a ratio of absolute viscosity increase at 40° C. to an absolute viscosity increase at 40° C. of an RL 216 reference oil of less than about 0.8.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.