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:
Nov. 10, 1981
Filed:
Aug. 04, 1980
Kensuke Sugiura, Kawasaki, JP;
Mineo Kagaya, Kawasaki, JP;
Hiroyuki Aoki, Urawa, JP;
Takeitiro Takehara, Yokohama, JP;
Nippon Oil Company, Ltd., both of, JP;
Nissan Motor Co., Ltd., both of, JP;
Abstract
In a central system fluid composition comprising (1) 70 to 95% by weight of a hydrocarbon base oil and (2) 5 to 30% by weight of a viscosity index improver, the improvement wherein said hydrocarbon base oil (1) comprises (a) 25% by weight to less than 50% by weight, based on the weight of the hydrocarbon base oil (1), of an oligomer of 1-decene having an average molecular weight of 200 to 600 and (b) more than 50% by weight to 75% by weight of a petroleum lubricating oil fraction, and said viscosity index improver (2) is a polymethacrylate having a viscosity average molecular weight of 10,000 to 700,000 obtained by polymerizing at least one ester of a saturated monohydric aliphatic alcohol having 1 to 18 carbon atoms with methacrylic acid.