| (19) |
 |
|
(11) |
EP 1 016 706 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
17.01.2001 Bulletin 2001/03 |
| (43) |
Date of publication A2: |
|
05.07.2000 Bulletin 2000/27 |
| (22) |
Date of filing: 24.12.1999 |
|
| (51) |
International Patent Classification (IPC)7: C10M 163/00
// (C10M163/00, 129:10, 129:54, 129:76, 133:56, 137:10, 159:22, 159:24), C10N30:04,
C10N30:10, C10N40:25 |
|
| (84) |
Designated Contracting States: |
|
AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE |
|
Designated Extension States: |
|
AL LT LV MK RO SI |
| (30) |
Priority: |
28.12.1998 JP 37312298
|
| (71) |
Applicant: ORONITE JAPAN LIMITED |
|
Minatu-ku, Tokyo (JP) |
|
| (72) |
Inventors: |
|
- Nagamatsu, Horoyuki
Gotenba-shi, Shizuoka (JP)
- Fujita, Koichi
Haibara-gun, Shizuoka (JP)
- Ando, Hiroki
Haibara-gun, Shizuoka (JP)
|
| (74) |
Representative: Nash, David Allan |
|
Haseltine Lake & Co., Imperial House, 15-19 Kingsway
London WC2B 6UD
London WC2B 6UD (GB) |
|
| |
|
| (54) |
Lubricating oil composition for internal combustion engines having improved thermal
oxidation durability and detergency |
(57) A lubricating oil composition for internal combustion engines comprising a base oil
of lubricating viscosity having a kinematic viscosity of 22 to 300 mm
2/s at 40°C, an overbased alkyloxybenzenesulfonate detergent, a neutral or basic salicylate
detergent, an ashless dispersant, a zinc dialkyldithiophosphate, and a nonmetallic
oxidation inhibitor.
The lubricating oil composition of the present invention has enough stability against
thermal oxidation and enough detergency at elevated temperatures to comply with the
severe operating conditions required for modern diesel engines and to satisfactorily
lubricate the engine even under severe friction conditions.