Mist oil lubricating compositions and methods

Abstract

Lubrication compositions comprising from about 80% to about 99.9% of a synthetic ester lubricant; and from about 0.1% to about 8% of a polyalkyl methacrylate mist suppressant. The synthetic ester lubricant may be an adipate ester lubricant, which may be a ditridecyl adipate, a phthalate ester lubricants, such as diisononyl phthalates and ditridecyl phthalates, or mixtures thereof. The compositions may also comprise a highly branched isoparaffinic polyalphaolefin lubricant. The lubricating compositions may also comprise one or more additives.

What is claimed is: 
     
         1 . A mist oil lubricating composition comprising:
 (a) from about 80% to about 99.9% of a synthetic ester lubricant; and   (b) from about 0.1% to about 8% of a polyalkyl methacrylate mist suppressant.   
     
     
         2 . The mist oil lubricating composition according to  claim 1 , wherein the lubricant has a viscosity of from about 10 to about 700 cSt at 40° C. 
     
     
         3 . The mist oil lubricating composition according to  claim 1 , wherein the lubricant comprises an adipate ester lubricant, a phthalate ester lubricant, or mixtures thereof. 
     
     
         4 . The mist oil lubricating composition according to  claim 3 , wherein the adipate ester lubricant is a ditridecyl adipate. 
     
     
         5 . The mist oil lubricating composition according to  claim 1 , wherein the ester lubricant is present at a level of about 90% to about 96% of the composition. 
     
     
         6 . The mist oil lubricating composition according to  claim 1 , wherein the adipate ester lubricant has a viscosity of from about 20 to about 35 cSt at 40° C. 
     
     
         7 . The mist oil lubricating composition according to  claim 1 , wherein the phthalate ester lubricant is selected from the group consisting of diisononyl phthalates, ditridecyl phthalates, and mixtures thereof. 
     
     
         8 . The mist oil lubricating composition according to  claim 1 , wherein the phthalate ester lubricant is present at a level of about 50% to about 99.9% of the composition. 
     
     
         9 . The mist oil lubricating composition according to  claim 1 , wherein the mist suppressant has a viscosity of from about 80 to about 2,500 cSt at 100° C. 
     
     
         10 . The mist oil lubricating composition according to  claim 9 , wherein the mist suppressant is a C 6  to C 18  methacrylate. 
     
     
         11 . The mist oil lubricating composition according  claim 1 , further comprising from about 0.1% to about 10% of a highly branched isoparaffinic polyalphaolefin lubricant. 
     
     
         12 . The mist oil lubricating composition according to  claim 11 , wherein the polyalphaolefin lubricant has a viscosity of from about 40 to about 55 cSt at 40° C. 
     
     
         13 . The mist oil lubricating composition according to  claim 1 , further comprising an additive selected from the group consisting of rust inhibitors, yellow metal deactivators, anti-wear agents, antioxidants, demulsifiers, anti-foam agents, extreme pressure agents, and mixtures thereof. 
     
     
         14 . The mist oil lubricating composition according to  claim 13 , wherein the additive is present at a level of from about 0.01% to about 5% of the composition. 
     
     
         15 . The mist oil composition according to  claim 1 , having a viscosity of 30 to about 160 cSt at 40° C. 
     
     
         16 . A method of mist oil lubrication of a surface, comprising applying a mist lubricant to the surface, the mist lubricant comprising:
 (a) from about 90% to about 99.9% of a synthetic ester lubricant; and   (b) from about 0.1% to about 8% of a polyalkyl methacrylate mist suppressant.   
     
     
         17 . A mist oil lubricating composition comprising:
 (a) from about 0% to about 96.5% of an adipate ester lubricant having a viscosity of from about 20 to about 35 cSt at 40° C.;   (b) from about 0% to about 96.5 of a phthalate ester lubricant having a viscosity of from about 35 to about 90 cSt at 40° C.;   (c) from about 1% to about 10% of a highly branched isoparaffinic polyalphaolefin lubricant having a viscosity of from about 40 to about 55 cSt at 40° C.;   (d) from about 0.1% to about 8% of a polyalkyl methacrylate mist suppressant; and   (e) from about 0.01% to about 5% of an additive selected from the group consisting of rust inhibitors, yellow metal deactivators, anti-wear agents, antioxidants, demulsifiers, anti-foam agents, extreme pressure agents, and mixtures thereof;   wherein the total level of the adipate ester lubricant and the phthalate ester lubricant is from about 80% to about 96.5%, preferably from about 90% to about 96%, and the composition has a viscosity of from about 20 to about 200 cSt at 40° C.   
     
     
         18 . The mist oil lubricating composition according to  claim 17 , wherein the phthalate ester lubricant is selected from the group consisting of diisononyl phthalates, ditridecyl phthalates, and mixtures thereof. 
     
     
         19 . The mist oil lubricating composition according to  claim 18 , comprising from about 0.5% to about 75% of a diisononyl phthalate lubricant and from about 0.5% to about 92% of a ditridecyl phthalate lubricant.