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:
Jan. 13, 1998
Filed:
Oct. 17, 1995
Atsushi Yokouchi, Kanagawa, JP;
Hideki Koizumi, Kanagawa, JP;
Kenichi Iso, Kanagawa, JP;
Michiharu Naka, Kanagawa, JP;
Toshiaki Endo, Kanagawa, JP;
Yoichi Suzuki, Kanagawa, JP;
NSK Ltd., Tokyo, JP;
Kyodo Yushi Co., Ltd., Tokyo, JP;
Abstract
A grease composition comprising a base oil containing not less than 10% by weight of an ester oil based on the total base oil and having a kinematic viscosity of 50 to 200 mm.sup.2 /sec at 40.degree. C. and 15 to 35% by weight, based on the total grease composition, of a diurea compound represented by formula (I): ##STR1## wherein R.sub.2 represents an aromatic hydrocarbon group having 6 to 15 carbon atoms; and R.sub.1 and R.sub.3, which may be the same or different, each represent an aromatic hydrocarbon group having 6 to 12 carbon atoms or an aliphatic hydrocarbon group having 8 to 20 carbon atoms, the proportion of the aromatic hydrocarbon groups in the total of R.sub.1 and R.sub.3 being 50 to 100 mol %. When applied to outer race rotating bearings, the grease composition is excellent in flaking resistance, leak resistance, and low noise properties and prevents premature seizing under high temperature and high speed conditions.