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:
Apr. 10, 2001
Filed:
Jul. 07, 1998
Ryousuke Kaneshige, Ichihara, JP;
Hideki Hirano, Ichihara, JP;
Masahide Tanaka, Ichihara, JP;
Kenichi Morizono, Kuga-gun, JP;
Keiji Okada, Kuga-gun, JP;
Mitsui Chemicals, Inc., Tokyo, JP;
Abstract
The present invention is directed towards a lubricating oil comprising a random copolymer of an &agr;-olefin/aromatic vinyl compound, wherein the copolymer has a viscosity falling within a specific range and comprises ethylene, an aromatic vinyl compound, and optionally an &agr;-olefin. The lubricating oil possesses excellent viscosity properties, thermal stability, oxidation stability, abrasion resistance, and compatibility with lubricating oil additives. The random copolymer having a different viscosity range is useful as a viscosity index improver and a compatibilizing agent for a lubricating oil. The invention also provides a lubricating oil composition comprising a base oil and the viscosity index improver or the compatibilizing agent. The invention further provides a fuel oil composition comprising a fuel oil fluidity improver based on the above random copolymer having a different viscosity range and a middle fraction fuel oil having a boiling point of 150 to 400° C. The fuel oil composition prevents an increase in viscosity of the middle fraction fuel oil, lowers the clogging point and the flow point in a low-temperature filter, and inhibits the abrasion of a fuel jet nozzle.