Urea grease composition

Abstract

The present invention aims to offer a urea grease composition which excels in noise performance, has long life at high temperatures and, further, also provides the basic performance of greases such as shear stability and heat resistance, as well as appropriate oil separation properties. The present invention provides a urea grease composition comprising: a diurea compound as shown by the General Formula (A) below: R 11 NHCONHR 12 NHCONHR 13 . . . (A), (where R 11 and R 13 are groups selected from the group consisting of hydrocarbon groups having from 6 to 20 carbons, at least one of R 11 and R 13 is a dodecyl group and R 12 is a diphenylme thane group); and a diurea compound as shown by the General Formula (B) below: R 21 NHCONHR 22 NHCONHR 23 . . . (B), (where R 21 and R 23 are groups selected from the group consisting of hydrocarbon groups having from 6 to 20 carbons, at least one of R 21 and R 23 is an oleyl group, and R 22 is a diphenylmethane group).

1 . A urea grease composition comprising:
 a diurea compound as shown by the General Formula (A) below:
   R 11 NHCONHR 12 NHCONHR 13    (A), 
   
     (where R 11  and R 13  are groups selected from the group consisting of hydrocarbon groups having from 6 to 20 carbons, at least one of R 11  and R 13  is a dodecyl group and R 12  is a diphenylmethane group); and
 a diurea compound as shown by the General Formula (B) below:
   R 21 NHCONHR 22 NHCONHR 23    (B), 
 
 
     (where R 21  and R 23  are groups selected from the group consisting of hydrocarbon groups having from 6 to 20 carbons, at least one of R 21  and R 23  is an oleyl group, and R 22  is a diphenylmethane group). 
   
   
       2 . A urea grease composition according to  claim 1 , wherein the proportion occupied by the dodecyl group in R 11  and R 13  in the above-mentioned General Formula (A) is from 2 to 70% by mol and/or the proportion occupied by the oleyl group(s) in R 21  and R 23  in the above-mentioned General Formula (B) is from 5 to 70% by mol. 
   
   
       3 . A urea grease composition according to  claim 1 , wherein the hydrocarbon group having from 6 to 20 carbons other than the dodecyl group in R 11  and R 13  in the above-mentioned General Formula (A) and/or the hydrocarbon group having from 6 to 20 carbons other than an oleyl group in R 21  and R 23  in the above-mentioned General Formula (B) is an octyl group. 
   
   
       4 . A urea grease composition according to  claim 3 , wherein the proportion occupied by the dodecyl group in R 11  or R 13  in the above-mentioned General Formula (A) is from 3 to 55% by mol, the proportion occupied by the oleyl group(s) in R 21  and R 23  in the above-mentioned General Formula (B) is from 5 to 55% by mol, and the proportion occupied by the octyl groups in R 11 , R 13 , R 21 , and R 23  is from 10 to 90% by mol. 
   
   
       5 . A urea grease composition comprising:
 diurea compounds as shown by the general formulas:
   R 1 NHCONHR 2 NHCONHR 1    (a) 
   and 
   R 3 NHCONHR 2 NHCONHR 3    (b) 
   
     and, further, a diurea compound or compounds as shown by the general formulas:
   R 1 NHCONHR 2 NHCONHR 4    (d) 
   and/or 
   R 3 NHCONHR 2 NHCONHR 4 ,   (e) 
 
     (where R 2  is a diphenylmethane group, R 1  is a hydrocarbon group having an octyl group as its main constituent, R 3  is a hydrocarbon group having from 14 to 20 carbons and containing at least 20% by mol of an oleyl group, and R 4  is a hydrocarbon group having a dodecyl group as its main constituent). 
   
   
       6 . A urea grease composition according to  claim 5  further comprising:
 a diurea compound as shown by the general formula:
   R 1 NHCONHR 2 NHCONHR 3 .   (c) 
   
   
   
       7 . A urea grease composition according to  claim 6  wherein the molar ratio of the diurea compound as shown by the above-mentioned general formula (a) in relation to the totality of diurea compounds is from 20 to 80% by mol. 
   
   
       8 . A urea grease composition comprising:
 a diurea compound as shown by the general formula:
   R 1 NHCONHR 2 NHCONHR 3    (c) 
   
     and, further, a diurea compound or compounds as shown by the general formulas:
   R 1 NHCONHR 2 NHCONHR 4    (d) 
   and/or 
   R 3 NHCONHR 2 NHCONHR 4 ,   (e) 
 
     (where R 2  is a diphenylmethane group, R 1  is a hydrocarbon group having an octyl group as its main constituent, R 3  is a hydrocarbon group having from 14 to 20 carbons and containing at least 20% by mol of oleyl group, and R 4  is a hydrocarbon group having a dodecyl group as its main constituent). 
   
   
       9 . A urea grease composition according to  claim 8  additionally comprising:
 a diurea compound as shown by the general formula:
   R 3 NHCONHR 2 NHCONHR 3 .   (b) 
   
   
   
       10 . A urea grease composition according to  claim 9  wherein the molar ratio of the diurea compound as shown by the above-mentioned general formula (c) in relation to the totality of diurea compounds is from 20 to 80% by mol. 
   
   
       11 . Method of improving the noise performance, by using a urea grease composition according to  claim 1 . 
   
   
       12 . Use of the urea grease composition according to  claim 1  for improving the noise performance. 
   
   
       13 . A urea grease composition according to  claim 2 , wherein the hydrocarbon group having from 6 to 20 carbons other than the dodecyl group in R 11  and R 13  in the above-mentioned General Formula (A) and/or the hydrocarbon group having from 6 to 20 carbons other than an oleyl group in R 21  and R 23  in the above-mentioned General Formula (B) is an octyl group. 
   
   
       14 . A urea grease composition according to  claim 13 , wherein the proportion occupied by the dodecyl group in R 11  or R 13  in the above-mentioned General Formula (A) is from 3 to 55% by mol, the proportion occupied by the oleyl group(s) in R 21  and R 23  in the above-mentioned General Formula (B) is from 5 to 55% by mol, and the proportion occupied by the octyl groups in R 11 , R 13 , R 21 , and R 23  is from 10 to 90% by mol.