Lubricant composition and method for producing same

Abstract

Provided a lubricant composition containing a lubricant base oil (A) and particles (B-1) containing a thickener (B), in which the particles (B-1) satisfy requirement (α): an arithmetic average particle diameter on a volume basis when the particles (B-1) are measured in an environment of 25° C. by a laser diffraction/scattering method is 10.0 μm or less, and the lubricant composition satisfies requirement (β):a ratio [(x1)/(x2)] of a shear viscosity (x1) at 40° C. at a shear rate of 5 sec −1 and a shear viscosity (x2) at 40° C. at a shear rate of 10,000 sec −1 is 2.0 or more and 100 or less.

1 : A lubricant composition, comprising:
 a lubricant base oil; and   particles comprising a thickener,   wherein an arithmetic average particle diameter of the particles on a volume basis is 10.0 μm or less when the particles are measured in an environment of 25° C. by a laser diffraction/scattering method, and a ratio of a shear viscosity of the lubricant composition at 40° C. at a shear rate of 5 sec −1  and a shear viscosity of the lubricant composition at 40° C. at a shear rate of 10,000 sec −1  is in a range of 2.0 to 100.   
     
     
         2 : The lubricant composition according to  claim 1 , wherein the thickener comprises a urea-based thickener. 
     
     
         3 : The lubricant composition according to  claim 1 , wherein a content of the thickener is 0.1 mass % or more and less than 2.0 mass % based on a total amount of the lubricant composition. 
     
     
         4 : An impregnation bearing oil, comprising:
 the lubricant composition of  claim 1 .   
     
     
         5 : A method of lubricating an oil-impregnated bearing or a machine tool, comprising:
 applying the lubricant composition of  claim 1  to an impregnation bearing or a machine tool.   
     
     
         6 : A method for producing a lubricant composition, comprising:
 mixing a lubricant base oil and a grease comprising particles comprising a thickener,   wherein an arithmetic average particle diameter of the particles in the grease on a volume basis is 5.0 μm or less when the particles are measured in an environment of 25° C. by a laser diffraction/scattering method.   
     
     
         7 : The method for producing the lubricant composition according to  claim 6 , wherein the thickener comprises a urea-based thickener. 
     
     
         8 : The method for producing the lubricant composition according to  claim 6 , wherein a content of the thickener in the grease is in a range of 3 mass % to 20 mass % based on a total amount of the grease. 
     
     
         9 : The method for producing the lubricant composition according to  claim 6 , wherein the grease has a, worked penetration of 310 or more at 25° C. 
     
     
         10 : A lubricating oil for a machine tool, comprising:
 the lubricant composition of  claim 1 .   
     
     
         11 : The lubricant composition according to  claim 2 , wherein a content of the thickener is 0.1 mass % or more and less than 2.0 mass % based on a total amount of the lubricant composition. 
     
     
         12 : An impregnation bearing oil, comprising:
 the lubricant composition of  claim 2 .   
     
     
         13 : A lubricating oil for a machine tool, comprising:
 the lubricant composition of  claim 2 .   
     
     
         14 : A method of lubricating an oil-impregnated bearing or a machine tool, comprising:
 applying the lubricant composition of  claim 2  to an impregnation bearing or a machine tools.   
     
     
         15 : An impregnation bearing oil, comprising:
 the lubricant composition of  claim 3 .   
     
     
         16 : A lubricating oil for a machine tool, comprising:
 the lubricant composition of  claim 3 .   
     
     
         17 : The method for producing the lubricant composition according to  claim 7 , wherein a content of the thickener in the grease is in a range of 3 mass % to 20 mass % based on a total amount of the grease. 
     
     
         18 : The method for producing the lubricant composition according to  claim 7 , wherein the grease has a worked penetration of 310 or more at 25° C. 
     
     
         19 : The method for producing the lubricant composition according to  claim 8 , wherein the grease has a worked penetration of 310 or more at 25° C. 
     
     
         20 : The method for producing the lubricant composition according to  claim 18 , wherein the grease has a worked penetration of 310 or more at 25° C.