Abstract: A lubricant composition includes a perfluoropolyether as a base oil, a fluororesin as a thickener, and a polyol ester, a urea grease and a zinc dialkyldithiophosphate as additives, wherein a mass ratio of content of the perfluoropolyether to total content of the polyol ester and the urea grease ranges from 78/22 to 95/5, a mass ratio of content of the perfluoropolyether to content of the polyol ester ranges from 90/10 to 96.5/3.5, a mass ratio of content of the polyol ester to content of the urea grease ranges from 40/60 to 65/35, content of the fluororesin ranges from 15 mass % to 24 mass % based on a total amount of the lubricant composition, and content of the zinc dialkyldithiophosphate ranges from 0.5 mass % to 4 mass % based on the total amount of the lubricant composition.

Abstract: A lubricant composition includes a perfluoropolyether as a base oil, a fluororesin as a thickener, and a polyol ester, a urea grease and a zinc dialkyldithiophosphate as additives, wherein a mass ratio of content of the perfluoropolyether to total content of the polyol ester and the urea grease ranges from 78/22 to 95/5, a mass ratio of content of the perfluoropolyether to content of the polyol ester ranges from 90/10 to 96.5/3.5, a mass ratio of content of the polyol ester to content of the urea grease ranges from 40/60 to 65/35, content of the fluororesin ranges from 15 mass % to 24 mass % based on a total amount of the lubricant composition, and content of the zinc dialkyldithiophosphate ranges from 0.5 mass % to 4 mass % based on the total amount of the lubricant composition.

Abstract: A process for producing a grease composition which is capable of homogeneously and surely dispersing a non-fluorine-based base oil blended with a thickening agent and a fluorine-based base oil blended with a thickening agent. A mixture of a non-fluorine-based base oil blended with a first thickening agent and a fluorine-based base oil blended with a second thickening agent that are not mutually compatible is homogeneously treated at a shear rate of 150 s?1 or higher to form a morphology structure in which one of the non-fluorine-based base oil and fluorine-based base oil is homogeneously dispersed in a particulate form having a mean particle diameter of not more than 25 ?m in the other base oil.

Abstract: A grease composition, which comprises a mixture of mutually incompatible thickener-containing non-fluorine-based base oil and thickener-containing fluorine-based base oil, the base oils being in a morphological structure, where one of the base oils is homogeneously dispersed in a particulate state in the other base oil, can be produced by kneading the mixture through a three-roll mill at least twice. By forming a morphological structure, one of the mutually incompatible non-fluorine-based base oil and fluorine-based base oil is homogeneously dispersed in a particulate state in the other base oil, that is, by forming a microscopically dispersed state, the following effects can be obtained: (1) less oil separation (smaller degree of oil separation) at elevated temperatures, (2) distinguished shearing stability, (3) low and stable friction coefficient, and (4) less abrasion.

Abstract: Disclosed is a lubricating grease composition comprising a complex metal soap thickener of aliphatic dicarboxylic acid and monoamide monocarboxylic acid, and a fluororesin powder contained in a base oil mixture of a non-fluorine-based base oil and a fluorine-based base oil, which are incompatible with each other. The lubricating grease composition can be produced by kneading, preferably kneading by a three-roll mill, a non-fluorine-based grease and a fluorine-based grease, the non-fluorine-based grease being prepared by stirring a non-fluorine-based base oil, aliphatic dicarboxylic acid, and monoamide monocarboxylic acid under heating, and adding metal hydroxide thereto to form a complex metal soap in the non-fluorine-based base oil; and the fluorine-based grease being prepared from a fluorine-based base oil and a fluororesin powder.

Abstract: A grease composition, which comprises a mixture of mutually incompatible thickener-containing non-fluorine-based base oil and thickener-containing fluorine-based base oil, the base oils being in a morphological structure, where one of the base oils is homogeneously dispersed in a particulate state in the other base oil, can be produced by kneading the mixture through a three-roll mill at least twice. By forming a morphological structure, one of the mutually incompatible non-fluorine-based base oil and fluorine-based base oil is homogeneously dispersed in a particulate state in the other base oil, that is, by forming a microscopically dispersed state, the following effects can be obtained (1) less oil separation (smaller degree of oil separation) at elevated temperatures, (2) distinguished shearing stability, (3) low and stable friction coefficient, and (4) less abrasion.

Abstract: A process for producing a grease composition which is capable of homogeneously and surely dispersing a non-fluorine-based base oil blended with a thickening agent and a fluorine-based base oil blended with a thickening agent. A mixture of a non-fluorine-based base oil blended with a first thickening agent and a fluorine-based base oil blended with a second thickening agent that are not mutually compatible is homogeneously treated at a shear rate of 150 s?1 or higher to form a morphology structure in which one of the non-fluorine-based base oil and fluorine-based base oil is homogeneously dispersed in a particulate form having a mean particle diameter of not more than 25 ?m in the other base oil.