The present invention provides a grease composition comprising (a) a base oil, (b) a thickener comprising a urea compound, (c) an amine antioxidant at 0.5 to 5% by mass based on a total mass of the composition, and (d) a quinoline antioxidant at 0.5 to 5% by mass based on the total mass of the composition.

The present invention provides a grease composition comprising (a) a base oil, (b) a thickener comprising a urea compound, (c) an amine antioxidant at 0.5 to 5% by mass based on a total mass of the composition, and (d) a quinoline antioxidant at 0.5 to 5% by mass based on the total mass of the composition.

A lubricant base oil composed of an ester. The ester includes a component (A) derived from trimethylolpropane in a molar percentage A.sub.mol% of 25 to 42 mol %; components (B) derived from monovalent straight-chain saturated fatty acids each having a carbon number of 8 to 12 in a molar percentage B.sub.mol% of 33 to 55 mol %: and a component (C) derived from adipic acid in a molar ratio C.sub.mol% of 12 to 34 mol %. The components (B) include lauric acid in a molar percentage of 5 to 50 mol %, and (B.sub.COOH+C.sub.COOH)/A.sub.OH is 0.90 to 1.02. A.sub.OH represents a hydroxyl equivalent of the component (A), B.sub.COOH represents a carboxyl group equivalent of the components (B); and C.sub.COOH represents a carboxyl group equivalent of the component (C).

A lubricant base oil composed of an ester. The ester includes a component (A) derived from trimethylolpropane in a molar percentage A.sub.mol% of 25 to 42 mol %; components (B) derived from monovalent straight-chain saturated fatty acids each having a carbon number of 8 to 12 in a molar percentage B.sub.mol% of 33 to 55 mol %: and a component (C) derived from adipic acid in a molar ratio C.sub.mol% of 12 to 34 mol %. The components (B) include lauric acid in a molar percentage of 5 to 50 mol %, and (B.sub.COOH+C.sub.COOH)/A.sub.OH is 0.90 to 1.02. A.sub.OH represents a hydroxyl equivalent of the component (A), B.sub.COOH represents a carboxyl group equivalent of the components (B); and C.sub.COOH represents a carboxyl group equivalent of the component (C).

Disclosed is a component-replaceable water ring vacuum pump in which inner components within a head unit may be disassembled and replaced without separation of the head unit from a main body, thus shortening an operation time and improving operation efficiency through prevention of leakage of an inner liquid during a replacement process. The water ring vacuum pump includes a main body provided with a shaft, a rotor rotated together with the shaft within the main body, a head unit coupled to both sides of the main body, a guide bearing provided within the head unit, and a mechanical seal configured to block inner gas. A bearing bracket to support the guide bearing is detachably fastened to one side of the head unit by a bolt, and an inner cap and an outer cap are assembled to the inner and outer surfaces of the bearing bracket by fixing bolts.

Provided is a lubricating oil composition containing a base oil (A); a molybdenum dithiophosphate (B1) in an amount of 400 ppm by mass or more as expressed in terms of a molybdenum atom; an organic metal-based detergent (C1) containing a metal atom selected from an alkali metal atom and an alkaline earth metal atom in an amount of 1,400 ppm by mass or less as expressed in terms of the metal atom; and a hindered amine-based antioxidant (D1) in an amount of 900 ppm by mass or more as expressed in terms of a nitrogen atom, with a sulfated ash content being 0.70% by mass or less. The lubricating oil composition may be one in which the detergency, the wear resistance, and the friction-reducing effect are improved with a well balance while reducing the ash content.

Provided is a lubricating oil composition containing a base oil (A); a molybdenum dithiophosphate (B1) in an amount of 400 ppm by mass or more as expressed in terms of a molybdenum atom; an organic metal-based detergent (C1) containing a metal atom selected from an alkali metal atom and an alkaline earth metal atom in an amount of 1,400 ppm by mass or less as expressed in terms of the metal atom; and a hindered amine-based antioxidant (D1) in an amount of 900 ppm by mass or more as expressed in terms of a nitrogen atom, with a sulfated ash content being 0.70% by mass or less. The lubricating oil composition may be one in which the detergency, the wear resistance, and the friction-reducing effect are improved with a well balance while reducing the ash content.

A dispersant includes the reaction product of an amine and at least one equivalent of glycidyl ether where the amine is selected from a group consisting of aminoethylpiperazine, bis(2-(piperazin-1-yl)ethyl)amine, 4,4-methylenebiscyclohexylamine, m-xylenediamine, diethylenetriamine, and triethylenetetramine and where the glycidyl ether has the structure (A), where R is selected from aromatic carbon chains, non-aromatic carbon chains and polyalkylene glycol groups. The dispersant is useful in a lubricant with a base oil for increasing soot dispersibility of the lubricant. ##STR00001##

A dispersant includes the reaction product of an amine and at least one equivalent of glycidyl ether where the amine is selected from a group consisting of aminoethylpiperazine, bis(2-(piperazin-1-yl)ethyl)amine, 4,4-methylenebiscyclohexylamine, m-xylenediamine, diethylenetriamine, and triethylenetetramine and where the glycidyl ether has the structure (A), where R is selected from aromatic carbon chains, non-aromatic carbon chains and polyalkylene glycol groups. The dispersant is useful in a lubricant with a base oil for increasing soot dispersibility of the lubricant. ##STR00001##

A composition is provided to comprise a non-aqueous medium and a 3,4-oxypyridinone compound of structure (I):

##STR00001##

with each A being oxygen and/or sulfur, and with a variety of substituents at R.sub.1-R.sub.5 to enable a solution or an at least semi-stable emulsion to be formed in the non-aqueous medium. Methods of use are included herein, which may be focused on situations where the composition can be used as a lubricant and/or coolant.