Lubricating compositions

Patent 5883057 Issued on March 16, 1999. Estimated Expiration Date:

October 17, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

3637503

Additive concentrates and lubricating compositions containing these concentrates
Patent #: 3994815
Issued on: 11/30/1976
Inventor: Coleman

Central system fluid composition
Patent #: 4031020
Issued on: 06/21/1977
Inventor: Sugiura , et al.

Multigrade lubricants containing interpolymers
Patent #: 4162985
Issued on: 07/31/1979
Inventor: Holubec

Hydrocarbon based central system fluid composition
Patent #: 4299714
Issued on: 11/10/1981
Inventor: Sugiura , et al.

Polymeric compositions, oil compositions containing said polymeric compositions, transmission fluids and hydraulic fluids
Patent #: 4594378
Issued on: 06/10/1986
Inventor: Tipton , et al.

Polymeric compositions comprising olefin polymer and nitrogen containing ester of a carboxy interpolymer
Patent #: 4654403
Issued on: 03/31/1987
Inventor: Tipton

Polymeric compositions comprising an oil-soluble polymer and an oil-soluble acrylate polymerization of product
Patent #: 4734446
Issued on: 03/29/1988
Inventor: Tipton

Lubricant blends having high viscosity indices
Patent #: 4912272
Issued on: 03/27/1990
Inventor: Wu

Lubricating composition
Patent #: 4956122
Issued on: 09/11/1990
Inventor: Watts, et al.

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Inventors

Assignee

The Lubrizol Corporation

Application

No. 953698 filed on 10/17/1997

US Classes:

508/469, Polymer of alpha, beta-olefinically unsaturated carboxylate monomer (e.g., polymethylmethacrylate, etc.)585/14For fuel use only

Examiners

Primary: Howard, Jacqueline V.

Attorney, Agent or Firm

Renner, Otto, Boisselle & Sklar

Foreign Patent References

736464 CA. 06/19/1966
1043322 CA. 11/19/1978
136377 EP. 09/19/1983
129414 EP. 06/19/1984
276320 EP. 07/19/1987
281060 EP. 03/19/1988
578435 EP. 06/19/1993
678569 EP. 04/19/1995
2245757 FR. 12/19/1973
2524118 DE. 12/19/1975
2161828 GB. 06/19/1985
8901507 WO. 02/19/1989
9506700 WO. 03/19/1995
9506701 WO. 03/19/1995

International Classes

C10M 143/00
C10M 145/00

Abstract

This invention relates to a lubricating composition comprising at least about 30% by weight of at least one mineral oil, having a kinematic viscosity of less than about 8 cSt at 100° C., (A) from about 5% to about 30% by weight at least one polymer having a Mw less than about 10,000, and (B) from about 2% to about 12% by weight of a polymer having a Mw greater than about 15,000, wherein the lubricating composition has a shear loss of less than about 15% in the 20 hour taper bearing shear test. The invention also relates to concentrates used in preparing shear stable lubricating compositions. The present combination of components provides good low and high temperature properties to mineral oils, even at high treat levels. These lubricants have good shear stability and in one aspect have improved oxidation resistance.