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:
May. 15, 2001
Filed:
Nov. 24, 1999
Toshihiko Ichihashi, Chiba-ken, JP;
Masayuki Kato, Chiba-ken, JP;
Takao Ishikawa, Kanagawa-ken, JP;
Yasuhiro Murakami, Kanagawa-ken, JP;
Kazuo Umesato, Kanagawa-ken, JP;
Rika Yauchihara, Kanagawa-ken, JP;
Other;
Abstract
There is disclosed a lubricating oil composition for automatic transmissions which comprises a base oil comprising at least one oil selected from the group consisting of a mineral oil and a synthetic oil each having a specific kinematic viscosity and a % C,; (A) a non-boron based succinic acid imide (e.g. polybutenylsuccinic acid imide) and a boron based succinic acid imide each in an amount of 0.1 to 5% by weight based on the whole composition; (B) a condensation product of a branched chain fatty acid having 8 to 30 carbon atoms (e.g. isostearic acid) and an amine (e.g. tetraethylene-pentamine) in an amount of 0.05 to 2% by weight based on the same; and (C) a dialkyl hydrogenphosphite (e.g. dioleyl hydrogenphosphite) in an amount of 0.1 to 1% by weight based on the same, and optionally at least one member selected from viscosity index improvers, antioxidants, metal deactivators, defoaming agents, detergents, extreme pressure agents and rust preventives. The lubricating oil composition mentioned above is enhanced in the capacity of transmission torque, excellent in the performance of preventing shudder, and prolonged in the service lifetime of shudder prevention and capacity of transmission torque.