Abstract: To provide a fuel-efficient lubricating oil composition, particularly suitable for internal combustion engines, which has a reduced shear viscosity in an intermediate temperature range from 80 to 100° C., an effective temperature range for reducing fuel consumption. The present invention provides a lubricating oil composition comprising a base oil incorporated with a viscosity index improver, wherein the viscosity index improver has a peak area at a chemical shift between 3.4 and 3.7 ppm in a spectral pattern observed by nuclear magnetic resonance analysis (1H-NMR) accounts for 5% or more of the total peak area.

Abstract: To provide a fuel-efficient lubricating oil composition, particularly suitable for internal combustion engines, which has a reduced shear viscosity in an intermediate temperature range from 80 to 100° C., an effective temperature range for reducing fuel consumption. The present invention provides a lubricating oil composition comprising a base oil incorporated with a viscosity index improver, wherein the viscosity index improver has a peak area at a chemical shift between 3.4 and 3.7 ppm in a spectral pattern observed by nuclear magnetic resonance analysis (1H-NMR) accounts for 5% or more of the total peak area.

Abstract: The present invention provides a lubricant oil composition, having enhanced wear-preventive characteristics for a diesel engine operating with large quantities of soot in the oil (soot content: 0.2 to 4.0 wt. %), and is especially suitable for a pressure-accumulating (common rail) type diesel engine equipped with an EGR system. The lubricant oil composition containing a base oil composed of a mineral and/or synthetic oil incorporated with at least three additives that are a sulfurized oxymolybdenum dithiocarbamate at 0.03 to 0.50 wt. % as Mo; a zinc dialkyl dithiophosphate at 0.04 to 0.50 wt. % as P; and at least one metallic salt of alkyl salicylate selected from the group consisting of a Ca salt of alkyl salicylate at 0.004 to 1.0 wt. % as Ca, Mg salt of alkyl salicylate at 0.002 to 0.60 wt. % as Mg, and Zn salt of alkyl salicylate at 0.006 to 1.60 wt. % as Zn, all percentages being based on the whole composition.

Abstract: The invention provides a lubricant oil composition useful for reduction in friction loss and improvement in fuel economy in internal combustion engines, particularly, a lubricant oil composition for internal combustion engines exhibiting an excellent friction reducing effect even in a diesel engine equipped with EGR accompanied with an increase in soot content in oil. The invention is a lubricant composition for internal combustion engines comprising a lubricant base oil consisting of a mineral oil and/or synthetic oil or the like incorporated with 1 wt % or more, based on the total weight of the lubricant oil composition, a nonionic surfactant with alkylene oxide added thereto consisting of at least one compound having an HLB value of 15 or more and a molecular weight of 900 or more, and a friction reducing method for internal combustion engines using this lubricant oil composition.

Abstract: The lubricating oil of the present invention exhibits an excellent effect of agglomerating solid impurity particles it contains to a sufficiently large size as to be captured and removed by an oil filter.

Abstract: The invention provides a lubricant oil composition useful for reduction in friction loss and improvement in fuel economy in internal combustion engines, particularly, a lubricant oil composition for internal combustion engines exhibiting an excellent friction reducing effect even in a diesel engine equipped with EGR accompanied with an increase in soot content in oil. The invention is a lubricant composition for internal combustion engines comprising a lubricant base oil consisting of a mineral oil and/or synthetic oil or the like incorporated with 1 wt % or more, based on the total weight of the lubricant oil composition, a nonionic surfactant with alkylene oxide added thereto consisting of at least one compound having an HLB value of 15 or more and a molecular weight of 900 or more, and a friction reducing method for internal combustion engines using this lubricant oil composition.

Abstract: The present invention provides a lubricant oil composition, having enhanced wear-preventive characteristics for a diesel engine operating with large quantities of soot in the oil (soot content: 0.2 to 4.0 wt. %), and is especially suitable for a pressure-accumulating (common rail) type diesel engine equipped with an EGR system. The lubricant oil composition containing a base oil composed of a mineral and/or synthetic oil incorporated with at least three additives that are a sulfurized oxymolybdenum dithiocarbamate at 0.03 to 0.50 wt. % as Mo; a zinc dialkyl dithiophosphate at 0.04 to 0.50 wt. % as P; and at least one metallic salt of alkyl salicylate selected from the group consisting of a Ca salt of alkyl salicylate at 0.004 to 1.0 wt. % as Ca, Mg salt of alkyl salicylate at 0.002 to 0.60 wt. % as Mg, and Zn salt of alkyl salicylate at 0.006 to 1.60 wt. % as Zn, all percentages being based on the whole composition.

Abstract: The present invention provides for a lubricant oil composition for internal combustion engines for automobiles with enhanced friction loss reduction and is especially suitable for a pressure-accumulating (common rail) type diesel engine equipped with an EGR system. The lubricant oil composition contains a base oil composed of a mineral and/or synthetic oil incorporated with at least four additives of (A) at least one type of organomolybdenum compound selected from the group consisting of sulfurized oxymolybdenum dithiocarbamate, sulfurized oxymolybdenum dithiophosphate, molybdenum phosphate and molybdenum-amine complex at 0.01 to 0.20 wt. % as Mo, (B) zinc dialkyl dithiophosphate at 0.01 to 0.50 wt. % as P, (C) one of Ca and Mg salts of alkyl salicylate at 0.05 to 1.0 wt. % as Ca or Mg and (D) Zn salt of alkyl salicylate at 0.005 to 0.2 wt.

Abstract: The present invention relates to a lubricant oil composition, comprising a base oil composed of a mineral and/or synthetic oil incorporated with at least two types of additives (A) and (B) described below, characterized by being used for diesel engines operating with large quantities of soot in their oil, in particular those equipped with an exhaust gas recirculation (EGR) system: (A) sulfurized oxymolybdenum dithiocarbamate at 0.03 to 0.50 wt % as Mo, based on the whole composition, and (B) zinc dialkyl dithiophosphate at 0.04 to 0.50 wt % as P, also based on the whole composition.

Abstract: A first refrigerating machine oil of the present invention has a sodium and/or potassium concentration of not higher than 0.1 ppm. Since it has low hydrolyzability and excellent insulating properties, the first refrigerating machine oil is useful as a refrigerating machine oil composition for refrigerators having a hermetic compressor. A second refrigerating machine oil of the present invention is composed mainly of an ester of pentaerythritol and a carboxylic acid. The carboxylic acid is a mixed carboxylic acid composed of 3,5,5-trimethylhexanoic acid and a straight-chain or branched fatty acid having from 6 to 8 carbon atoms. The proportion of 3,5,5-trimethylhexanoic acid in the mixed carboxylic acid is in the range of from more than 50 mol % to not more than 90 mol %.

Abstract: The lubricating oil for refrigerator according to the present invention is a lubricating oil for refrigerator using 1,1,1,2-tetrafluoroethane refrigerant. Having esters as base oil, its viscosity range is between 2-30 mm/s at 100.degree.C. By adding esters alone or by adding esters having different viscosity to esters base oil, or by adding polymer, the viscosity is adjusted to obtain the lubricating oil suitable for various types of refrigerators. The lubricating oil thus obtained has excellent compatibility with 1,1,1,2-tetrafluoroethane refrigerant, which is an alternative to freon, and has low hygroscopic property and high heat-resistant property.By reducing the total acid number to 0.05 mg KOH/g or less, the corrosion-resistant property and insulating property of lubricating oil are not decreased, and the lubricating oil for refrigerator having having high refrigerant stability, hydrolytic stability and insulating property can be obtained.