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:
Mar. 25, 2025
Filed:
Sep. 14, 2021
Sanyo Chemical Industries, Ltd., Kyoto, JP;
Nobuhiro Naito, Kyoto, JP;
Satoshi Matsumoto, Kyoto, JP;
Masahiro Hashimoto, Kyoto, JP;
Kenyuu Yoshida, Kyoto, JP;
Hiroki Yamashita, Kyoto, JP;
Ryota Sato, Kyoto, JP;
SANYO CHEMICAL INDUSTRIES, LTD., Kyoto, JP;
Abstract
The present invention aims to provide a viscosity-index improving agent having an excellent friction reduction effect to reduce friction of a lubricating oil composition when the viscosity-index improving agent is added thereto. The present also aims to provide a lubricating oil composition containing the viscosity-index improving agent. The present invention relates to, for example, a viscosity-index improving agent containing: (co)polymer (A) containing, as an essential constituent monomer, a polyolefin-based monomer (a) represented by the following formula (1); an ester oil (B1) having a kinematic viscosity at 100° C. of 1.00 to 2.50 mm/s; and an ester oil (B2) having a kinematic viscosity at 100° C. of 2.51 to 5.00 mm/s: wherein Ris a hydrogen atom or a methyl group; —X— is a group represented by —O—, —O(AO)-, or —NH—, A is a C2-C4 alkylene group, m is an integer of 1 to 10, and each A may be the same or different when m is 2 or more; Ris a residue after removal of one hydrogen atom from a hydrocarbon polymer containing a 1,2-butylene group as a structural unit; and p represents a number of 0 or 1.