Title:
LUBRICANT OIL COMPOSITION FOR INTERNAL COMBUSTION ENGINE
Document Type and Number:
Japanese Patent JP2004083746
Kind Code:
A
Abstract:
To provide a lubricant oil composition for an internal combustion engine, having extremely superior base number-maintaining characteristics, high-temperature cleanliness and properties for preventing friction of a valve operating system, and substantially free from a friction-preventing agent containing phosphorus and/or sulfur.
The lubricant oil composition contains (A) 0.001-0.5 wt.% ester of boric acid expressed in terms of boron element and (B) 0.01-5 wt.% ashless antioxidant based on the whole amount of the composition in a base oil of a lubricant oil comprising a mineral oil and/or a synthetic oil, and contains substantially no metal salt of dithiophosphoric acid and ≤0.2 wt.% sulfur based on the amount of the composition.
Inventors:
YAGISHITA KAZUHIRO
Application Number:
JP2002246836A
Publication Date:
March 18, 2004
Filing Date:
August 27, 2002
Export Citation:
Assignee:
NIPPON OIL CORP
International Classes:
C10M101/02; C10M129/10; C10M129/76; C10M133/12; C10M133/44; C10M133/56; C10M139/00; C10M141/12; C10M159/22; C10M159/24; C10M169/04; F16H53/00; F16C33/32; F16C33/62; F16H53/06; C10N10/04; C10N30/04; C10N30/06; C10N30/10; C10N40/25; (IPC1-7): C10M169/04; C10M101/02; C10M129/10; C10M129/76; C10M133/12; C10M133/56; C10M139/00; C10M159/22; C10M159/24
Attorney, Agent or Firm:
Tetsuro Hoshino
Akihiko Yamashita
Kishimoto Tatsuto
Akihiko Yamashita
Kishimoto Tatsuto