A lubrication method including lubricating a sliding member which contains at least one selected from the group consisting of a liquid crystal polymer and polyetheretherketone by using a lubricating oil composition which contains an ester as a lubricating base oil.

A lubrication method including lubricating a sliding member which contains at least one selected from the group consisting of a liquid crystal polymer and polyetheretherketone by using a lubricating oil composition which contains an ester as a lubricating base oil.

The present invention relates to a use of a lubricant comprising a base oil selected from a carboxylic acid ester in an electric vehicle. It further relates to a method for lubricating an electric vehicle with a lubricant comprising the carboxylic acid ester.

A grease composition comprising a thickener and a lubricating base oil, wherein the lubricating base oil has a viscosity in the range of from 5-1000 cSt (at 40° C.). The thickener is present in an amount of 5-40 wt. %, based on total weight of the grease composition. The thickener comprises an ester terminated oligomer which has the general formula: “R1—O—[CO—R2—CO—NH—R3—NH—CO—R2—CO]n-O—R1”. “R1” represents a hydrocarbon group containing 4-22 carbon atoms. “R2” represents a hydrocarbon group containing 4-42 carbon atoms. “R3” represents a hydrocarbon group containing 2-9 carbon atoms. “n” represents an integer in the range of 1-20. The weight ratio between the lubricating base oil and the ester terminated oligomer (oil/oligomer) is larger than 1. The grease composition can be used for lubricating a mechanical component having a metal surface and/or for protecting a mechanical component having a metal surface against corrosion, wear and/or fretting.

A grease composition comprising a thickener and a lubricating base oil, wherein the lubricating base oil has a viscosity in the range of from 5-1000 cSt (at 40° C.). The thickener is present in an amount of 5-40 wt. %, based on total weight of the grease composition. The thickener comprises an ester terminated oligomer which has the general formula: “R1—O—[CO—R2—CO—NH—R3—NH—CO—R2—CO]n-O—R1”. “R1” represents a hydrocarbon group containing 4-22 carbon atoms. “R2” represents a hydrocarbon group containing 4-42 carbon atoms. “R3” represents a hydrocarbon group containing 2-9 carbon atoms. “n” represents an integer in the range of 1-20. The weight ratio between the lubricating base oil and the ester terminated oligomer (oil/oligomer) is larger than 1. The grease composition can be used for lubricating a mechanical component having a metal surface and/or for protecting a mechanical component having a metal surface against corrosion, wear and/or fretting.

A process for the manufacture of a lubricating grease composition, the process comprising steps of: (a) providing an essentially homogeneous liquid composition comprising a lubricating oil and a thickening polymer, and (b) flowing the liquid composition through a shear-mixing device to mix and cool the liquid composition to form a lubricating grease composition.

A process for the manufacture of a lubricating grease composition, the process comprising steps of: (a) providing an essentially homogeneous liquid composition comprising a lubricating oil and a thickening polymer, and (b) flowing the liquid composition through a shear-mixing device to mix and cool the liquid composition to form a lubricating grease composition.

The present invention provides a refrigerating machine oil composition comprising an ester-based base oil, an epoxy compound, and a carbodiimide compound, the refrigerating machine oil composition being used with a refrigerant containing a fluoropropene in a refrigerating machine comprising a member containing polyethylene terephthalate and/or a member containing hydrogenated acrylonitrile butadiene rubber.

The present invention provides a refrigerating machine oil composition comprising an ester-based base oil, an epoxy compound, and a carbodiimide compound, the refrigerating machine oil composition being used with a refrigerant containing a fluoropropene in a refrigerating machine comprising a member containing polyethylene terephthalate and/or a member containing hydrogenated acrylonitrile butadiene rubber.

The present invention provides a working fluid composition for a refrigerating machine, comprising: a refrigerating machine oil comprising, as a base oil, a mixed ester of (A) a complex ester obtainable by synthesis of at least one polyhydric alcohol selected from neopentyl glycol, trimethylolpropane and pentaerythritol, a C6-C12 polybasic acid, and a C4-C18 monohydric alcohol or a C4-C18 monocarboxylic fatty acid, and (B) a polyol ester obtainable by synthesis of at least one polyhydric alcohol selected from neopentyl glycol, trimethylolpropane, pentaerythritol and dipentaerythritol, and a C4-C18 monocarboxylic fatty acid, in a mass ratio of (A) the complex ester/(B) the polyol ester of 5/95 to 95/5; and a hydrocarbon refrigerant having 3 or 4 carbon atoms, wherein a refrigerant dissolved viscosity, at a temperature of 80° C. and an absolute pressure of 1.5 MPa, is 1.0 mm.sup.2/s or more.