To produce a grease which has a high b.p., is excellent in texture, and has a high commodity value by mixing a base oil with a dispersant and a 12-30C monocarboxylic acid and mixing the resultant mixture with an aq. metal soln. contg. a 6-10C aliph. dicarboxylic acid dissolved therein in advance to thereby form a metal soap.
30-90 pts.wt. base oil comprising a mineral oil and/or a synthetic oil and having a kinematic viscosity (at 40°C) of 5-500 cSt, 0.1-5 pts.wt. dispersant (e.g. a combination of barium sulfonate with calcium sulfonate), 3-20 pts.wt. 12-30C monocarboxylic acid (e.g. 12-hydroxystearic acid), and a part of 0.5-20 pts.wt. aliph. dicarboxylic acid (e.g. azelaic acid) are mixed and stirred at 80-110°C. The resultant mixture is mixed with a soln. prepd. by dissolving the rest to the aliph. dicarboxylic acid in an aq. soln. of 1-20 pts.wt. metal- contg. material (e.g. lithium hydroxide), and the resultant metal soap is homogeneously dispersed and is further heated to 150-215°C to give a grease having a high b.p. and a low solid content.
SUGIMOTO HIDEYOSHI
MAMIYA ISAO
KATO KAZUO
CHUO YUKA