The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 01, 1998
Filed:
Feb. 27, 1998
Ian Macpherson, Richmond, VA (US);
Lee D Saathoff, Glen Allen, VA (US);
Marsha J Lester, Richmond, VA (US);
Ethyl Corporation, Richmond, VA (US);
Abstract
A clean performing gear oil for use in transmission oils and axle lubricants is provided. The gear oil having a Brookfield Viscosity at -12.degree. C. ranging from about 1,000 to about 150,000 cP, comprises a base oil having a kinematic viscosity at 100.degree. C. ranging from about 4.0 to about 41.0 cSt. Combined with the base oil is preferably a dispersant pour point depressant and/or a dispersant viscosity index improver. In a further preferred embodiment, the gear oil is essentially devoid of carboxylic-type ashless dispersants (e.g., succinimide dispersants) and Mannich base dispersants, thus realizing a cost saving over conventional gear oils which are used as transmission and axle lubricants. Functionalized polymethylacrylates (PMA) are disclosed as agents that improve the properties of the gear oil and allow for the omission of conventional dispersants.