Lubricating grease composition and method for producing the same

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.

1 . 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. 
     
     
         2 . The lubricating grease composition according to  claim 1 , which comprises a mixture of two kinds of greases, one grease comprising a complex metal soap thickener of aliphatic dicarboxylic acid and monoamide monocarboxylic acid contained in a non-fluorine-based base oil, and the other grease comprising a fluororesin powder contained in a fluorine-base base oil. 
     
     
         3 . The lubricating grease composition according to  claim 1 , wherein the non-fluorine-based base oil is a synthetic hydrocarbon oil or an ether-based synthetic oil. 
     
     
         4 . The lubricating grease composition according to  claim 2 , wherein the non-fluorine-based base oil is a synthetic hydrocarbon oil or an ether-based synthetic oil. 
     
     
         5 . The lubricating grease composition according to  claim 1 , wherein the complex metal soap is a barium complex soap. 
     
     
         6 . The lubricating grease composition according to  claim 2 , wherein the complex metal soap is a barium complex soap. 
     
     
         7 . The lubricating grease composition according to  claim 1 , wherein the fluorine-based base oil is used at a ratio of 95 to 5 wt. % with respect to 5 to 95 wt. % of the non-fluorine-based base oil. 
     
     
         8 . The lubricating grease composition according to  claim 1 , wherein the fluorine-based base oil is used at a ratio of 90 to 10 wt. % with respect to 10 to 90 wt. % of the non-fluorine-based base oil. 
     
     
         9 . A method for producing a lubricating grease composition, the method comprising: kneading 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 oil and a fluororesin powder.   
     
     
         10 . The method for producing a lubricating grease composition according to  claim 9 , wherein the non-fluorine-based grease and the fluorine-based grease are each prepared by kneading through a three-roll mill or a high-pressure homogenizer. 
     
     
         11 . The method for producing a lubricating grease composition according to  claim 9 , wherein the non-fluorine-based grease and the fluorine-based grease are kneaded by a three-roll mill. 
     
     
         12 . The method for producing a lubricating grease composition according to  claim 9 , wherein a synthetic hydrocarbon oil or an ether-based synthetic oil is used as the non-fluorine-based base oil. 
     
     
         13 . The method for producing a lubricating grease composition according to  claim 9 , wherein barium hydroxide is used as the metal hydroxide.