| 摘要 |
PROBLEM TO BE SOLVED: To obtain a grease composition having an excellent thermal stability, low oil-separation, long life and radiation resistance by formulating an amide compound having a specific structure as a thickener. SOLUTION: This grease composition comprises a base oil and 2-50 wt.% thickener based on the whole amount of the composition, and further the thickener contains 50-100 wt.% compound of formula I [R<1> and R<4> are each aromatic residue having an ether bond; R<2> and R<3> are each a 1-24 C divalent organic residue; (a) is 1-10] based on the whole amount of the thickener. A compound having a structure of formula II in the compounds of formula I is preferable in a view of a radiation resistance. The objective composition is preferably obtained by reacting a mixture of a primary aromatic monoamine of the formula R<1> -NH2 and a diamine of the formula H2 N-R<3> -NH2 with a dicarboxylic acid of the formula HOOC-R<2> -COOH or a derivative thereof in the base oil. The above monoamine is preferably 4-aminodiphenyl ether. The diamine is preferably bis(aminophenyl)methane. |
