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 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 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 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 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: A lubricant and combination lubricant and refrigerant composition for use in a refrigerating machine in which a substitute freon refrigerant, which lubricant contains a polymer of a fumaric ester or a fumaric ester and a copolymerizable alkylene, and optionally contains an organic carboxylic ester or a polyalkylene glycol with a kinematic viscosity of 2 to 30 cSt. The lubricant is compatible with substitute freon refrigerants such as hydrogen-containing halogenated hydrocarbons, particularly R 134a, in a wide temperature range, has a high viscosity index, is thermally and chemically stable, and has an excellent lubricity.

Abstract: A fluid composition for use in fluid couplings has the superior anti-gelling properties of an organopolysiloxane base oil, is low in changes in viscosity and changes in torque, is stable and has extremely high durability, and is especially useful because of its viscosity as a fluid for "fan" couplings. The fluid composition according to the invention is provided, by adding at least one type of ferrocene derivative, in a weight ratio wherein the atomic iron content is 10 ppm to 5,000 ppm, selected from the group consisting of the compounds represented by the general formula (1) and the general formula (2) for an organopolysiloxane base oil having a viscosity of 50 mm.sup.2 /s to 20,000 mm.sup.2 /s at 25.degree. C. The compounds of general formula (1) may be represented by the following formula: ##STR1## wherein R.sub.1 and R.sub.2 are identical or different, and are each independently selected from the group consisting of C.sub.2-25 alkyl, alkenyl, cyclo-alkyl, and cyclo-alkenyl. Additionally, one of R.sub.

Abstract: The invention provides a fluid composition for a fluid coupling, which is excellent in viscosity stability and torque stability, and comprises a polyorganosiloxane base oil having a viscosity of 3,000-500,000 mm.sup.2 /sec at 25.degree. C. and at least one 5-membered heterocyclic compound incorporated in a proportion of 0.01-3.0 wt. % based on the total weight of the composition, said 5-membered heterocyclic compound being selected from the group consisting of thiadiazole derivatives and thiazole derivatives, both, having at least one monovalent group represented by the formula --S.sub.x --R.sup.6 in which R.sup.6 is a saturated or unsaturated monovalent group or atom composed of at least one atom selected from a carbon atom, a hydrogen atom, an oxygen atom, a nitrogen atom and a sulfur atom, and x is a number of 1 or greater.

Abstract: A lubricating oil composition for two-cycle engines, consisting essentially of, by weight: (1) 30% to 70% of a polyol ester having a kinematic viscosity of 9 to 15 cSt at 100.degree. C., 30% to 70% of a diester having a kinematic viscosity of 2 to 5 cSt at 100.degree. C., 1% to 5% of a polybutene having a molecular weight of 500 to 2,500 and/or 1% to 5% of a polymethacrylate having a molecular weight of 5,000 to 40,000, and 5% to 25% of a dispersant; or (2) 30% to 70% of a polyol ester having a kinematic viscosity of 4 to 15 cSt at 100.degree. C., 0% to 35% of a complex ester having a kinematic viscosity of 10 to 14 cSt at 100.degree. C., 10% to 70% of a diester having a kinematic viscosity of 2 to 5 cSt at 100.degree. C., and. 5% to 25% of a dispersant; or (3) a lubricating oil base, 5% to 25% of a polyamide dispersant, and 0.1% to 5% of a combination of a neutral calcium sulfonate and a neutral calcium salicylate, based on the total weight of the composition.

Abstract: The invention concerns a lubricating oil composition in which a lubricating oil base contains 0.1% by weight to 20% by weight of an aromatic glycidyl carboxylate having the following general formula (1): ##STR1## wherein R is a C.sub.6-14 aryl or alkylaryl group, and n represents an integer of 1 or 2, and/or 0.05% by weight to 10% by weight of a phosphonate type additive having the following general formula (2): ##STR2## where R.sub.1 or R.sub.2 is selected from the group consisting of alkyl, aralkyl, aryl and hydroxyalkyl groups that may or may not have a substitute, and two R.sub.2 groups may be identical with or different from each other, and which is excellent in stability to hydrolysis, heat and oxidation as well as in lubricating properties, and so provides a particularly excellent refrigerating oil composition.

Abstract: The invention concerns a lubricating oil composition in which a lubricating oil base contains 0.1% by weight to 20% by weight of an aromatic glycidyl carboxylate having the following general formula (1): ##STR1## wherein R is a C.sub.6-14 aryl or alkylaryl group, and n represents an integer of 1 or 2, and/or 0.05% by weight to 10% by weight of a phosphonate type additive having the following general formula (2): ##STR2## where R.sub.1 or R.sub.2 is selected from the group consisting of alkyl, aralkyl, aryl and hydroxyalkyl groups that may or may not have a substitute, and two R.sub.2 groups may be identical with or different from each other, and which is excellent in stability to hydrolysis, heat and oxidation as well as in lubricating properties, and so provides a particularly excellent refrigerating oil composition.

Abstract: A traction fluid lubricant is disclosed which contains a naphthenic ingredient having a weight average molecular weight of 200-300 and obtained by hydrogenating oligomers of cyclopentadiene having a ratio of the number of norbornenic double bond to that of cyclopentenic double bond of smaller than 0.9 but not smaller than 0.1. The naphthenic ingredient is suitably used in conjunction with an auxiliary ingredient selected from a polybutene having a viscosity of 5-60 cSt at 40.degree. C. and a bicyclohexyl compound.