Grease composition and rolling bearing

Patent metadata

Field	Value
Publication number	US-2020407659-A1
Application number	US-202016906009-A
Country	US
Kind code	A1
Filing date	Jun 19, 2020
Priority date	Jun 25, 2019
Publication date	Dec 31, 2020
Grant date	—

Abstract

A grease composition includes a base oil, a thickener, and zirconium oxide particles. The base oil is a poly-α-olefin. The zirconium oxide particles have a median diameter D50 of 0.6 μm to 4 μm. A content of the zirconium oxide particles is 2% by mass to 15% by mass with respect to a total amount of the base oil and the thickener.

First claim

What is claimed is:

1 . A grease composition comprising:
a base oil; a thickener; and zirconium oxide particles, wherein the base oil is a poly-α-olefin, the zirconium oxide particles have a median diameter D 50 of 0.6 μm to 4 μm, and a content of the zirconium oxide particles is 2% by mass to 15% by mass with respect to a total amount of the base oil and the thickener.

2 . The grease composition according to claim 1 , wherein the thickener is a diurea represented by the following structural formula (1):
R 1 —NHCONH—R 2 —NHCONH—R 3   (1)

wherein, in the formula (1), R 1 and R 3 are each independently a functional group represented by the following formula (2) and R 2 is —C 6 H 4 —CH 2 —C 6 H 4 —;

a bonding position of each —C 6 H 4 — contained in R 2 with N is a 4-position when the bonding position of —C 6 H 4 — with —CH 2 —is considered as a 1-position; and
in the formula (2), R 4 is an alkyl group having 1 to 12 carbon atoms.

3 . The grease composition according to claim 1 , wherein the content of the thickener is 10% by mass to 30% by mass with respect to the total amount of the base oil and the thickener.

4 . The grease composition according to claim 1 , further comprising at least one of a rust inhibitor and an antioxidant.

5 . A rolling bearing in which the grease composition according to claim 1 is sealed.

Assignees

• Jtekt Corp

Inventors

• Hagino Yurie
• Tsuda Takeshi

Classifications

• C10M2217/0456

  used as thickening agents · CPC title

• C10M169/00 Primary

  Lubricating compositions characterised by containing as components a mixture of at least two types of ingredient selected from base-materials, thickeners or additives, covered by the preceding groups, each of these compounds being essential · CPC title

• F16N15/00

  Lubrication with substances other than oil or grease; Lubrication characterised by the use of particular lubricants in particular apparatus or conditions (F16N17/00 takes precedence; lubricating compositions, selection of particular substances as lubricants in general C10M) · CPC title

• C10M177/00

  Special methods of preparation of lubricating compositions; Chemical modification by after-treatment of components or of the whole of a lubricating composition, not covered by other classes · CPC title

• C10M2201/062

  Oxides; Hydroxides; Carbonates or bicarbonates · CPC title