| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lubricant composition in which all of sludge suppression property, abrasion resistance, and friction characteristics can be attained in a high level and with a sufficient balance, and which is excellent also in water separability. <P>SOLUTION: The lubricant composition includes a predetermined base oil, a thiophosphoric acid ester, a distributed viscosity index improver, a compound expressed by formulae (11)-(13): R<SP POS="POST">27</SP>-CO-NR<SP POS="POST">28</SP>-(CH<SB POS="POST">2</SB>)<SB POS="POST">p</SB>-COOZ<SP POS="POST">1</SP>(11); [R<SP POS="POST">29</SP>-CO-NR<SP POS="POST">30</SP>-(CH<SB POS="POST">2</SB>)<SB POS="POST">q</SB>-COO]<SB POS="POST">r</SB>Z<SP POS="POST">2</SP>(12) and [R<SP POS="POST">31</SP>-CO-NR<SP POS="POST">32</SP>-(CH<SB POS="POST">2</SB>)<SB POS="POST">s</SB>-COO]<SB POS="POST">t</SB>-Z<SP POS="POST">3</SP>-(OH)<SB POS="POST">u</SB>(13), and/or a compound expressed by formula (14): R<SP POS="POST">33</SP>-CH<SB POS="POST">2</SB>COOH (14) (wherein R<SP POS="POST">27</SP>, R<SP POS="POST">29</SP>and R<SP POS="POST">31</SP>are each 6C-30C alkyl or the like; R<SP POS="POST">28</SP>, R<SP POS="POST">30</SP>and R<SP POS="POST">32</SP>are each 1C-4C alkyl; Z<SP POS="POST">1</SP>is hydrogen or the like; Z<SP POS="POST">2</SP>is an alkali metal or the like; Z<SP POS="POST">3</SP>is a residue of a polyhydric alcohol removing a hydroxy group; p and s are each an integer of 1-4; r is 1 or 2; t is an integer of at least one; u is an integer of at least zero, and R<SP POS="POST">33</SP>is 7C-29C alkyl or the like). <P>COPYRIGHT: (C)2012,JPO&INPIT |
