Abstract: A lubricating oil composition contains a base oil and a rust inhibitor, in which the base oil has a gas chromatogram measured by gas chromatography satisfying the particular condition (?), and the rust inhibitor is at least one selected from a first rust inhibitor, a second rust inhibitor, a third rust inhibitor, and a fourth rust inhibitor, and satisfies the particular condition (?).

Abstract: A lubricating oil composition including a base oil (X) having a tertiary carbon atom at a content of 8.0 at % or more based on the total carbon of hydrocarbons and an antioxidant (Y) having an amine-based antioxidant (A), a phenol-based antioxidant (B), and a phosphor-based antioxidant (C). The amine-based antioxidant (A) includes a diphenylamine compound (A1) represented by the following general formula (a1): where Ra1 and Ra2, na1 and na2 are defined in the disclosure.

Abstract: Provided is a lubricating oil composition for air compressors containing a polyalkylene glycol-containing base oil (A) and a rust-preventive agent (B), wherein the content of the polyalkylene glycol is 65.0% by mass or more based on the total amount of the composition. The lubricating oil composition is excellent in oxidation stability and also in rust prevention and storage stability. Also provided are an air compressor lubricating method and an air compressor using the lubricating oil composition.

Abstract: Provided is a lubricating oil composition containing a mineral base oil (A) having a temperature gradient ?|Dt| of a distillation temperature between two points of a distillation amount of 2.0% by volume and a distillation amount of 5.0% by volume in a distillation curve of 6.8° C./% by volume or less, and an antioxidant (B) containing an amine-based antioxidant (B1), a phenol-based antioxidant (B2), and a phosphorus-based antioxidant (B3), wherein the content of the component (B3) is 0.06 to 1.0% by mass based on the total amount of the lubricating oil composition. The lubricating oil composition is a long-life lubricating oil composition that maintains excellent oxidation stability even for long-term use in a high-temperature environment, and has a high effect of suppressing the generation of sludge for a long period of time.

Abstract: Provided is a mineral base oil that conforms to viscosity grades VG22 to VG100 as defined in ISO 3448 and exhibits a distillation curve with a temperature gradient ?|DT| of distillation temperature between two points of 2.0 vol % and 5.0 vol % of distillation amount being 6.8° C./vol % or less. A vacuum pump oil containing the mineral base oil is excellent in vacuum characteristics and can conform to viscosity grades VG22 to VG100 as defined in ISO 3448.

Abstract: Provided is a lubricating oil composition for air compressors containing a polyalkylene glycol-containing base oil (A) and a rust-preventive agent (B), wherein the content of the polyalkylene glycol is 65.0% by mass or more based on the total amount of the composition. The lubricating oil composition is excellent in oxidation stability and also in rust prevention and storage stability. Also provided are an air compressor lubricating method and an air compressor using the lubricating oil composition.

Abstract: Provided is a vacuum pump oil which contains a mineral oil (A) having a temperature gradient ?|?*| of complex viscosity between two points of t(° C.) and t?10(° C.) (where ?15?t??10), as measured using a rotary rheometer at an angular velocity of 6.3 rad/s, of 10 Pa·s/° C. or less, and one or more compounds selected from a phenol-based compound (B) and an amine-based compound (C), and which has a viscosity index of less than 160. The vacuum pump oil has a good ultimate vacuum degree and is excellent in water separability, oxidation stability and shear stability, and is therefore applicable to various applications.

Abstract: Provided is a vacuum pump oil which contains a mineral oil (A) having a temperature gradient ?|?*| of complex viscosity between two points of t(° C.) and t?10(° C.) (where ?15?t??10), as measured using a rotary rheometer at an angular velocity of 6.3 rad/s, of 10 Pa·s/° C. or less, and one or more compounds selected from a phenol-based compound (B) and an amine-based compound (C), and which has a viscosity index of less than 160. The vacuum pump oil has a good ultimate vacuum degree and is excellent in water separability, oxidation stability and shear stability, and is therefore applicable to various applications.

Abstract: Provided is a lubricating oil composition containing a mineral base oil (A) having a temperature gradient ?|Dt| of a distillation temperature between two points of a distillation amount of 2.0% by volume and a distillation amount of 5.0% by volume in a distillation curve of 6.8° C./% by volume or less, and an antioxidant (B) containing an amine-based antioxidant (B1), a phenol-based antioxidant (B2), and a phosphorus-based antioxidant (B3), wherein the content of the component (B3) is 0.06 to 1.0% by mass based on the total amount of the lubricating oil composition. The lubricating oil composition is a long-life lubricating oil composition that maintains excellent oxidation stability even for long-term use in a high-temperature environment, and has a high effect of suppressing the generation of sludge for a long period of time.

Abstract: Provided is a mineral base oil that conforms to viscosity grades VG22 to VG100 as defined in ISO 3448 and exhibits a distillation curve with a temperature gradient ?|DT| of distillation temperature between two points of 2.0 vol % and 5.0 vol % of distillation amount being 6.8° C./vol % or less. A vacuum pump oil containing the mineral base oil is excellent in vacuum characteristics and can conform to viscosity grades VG22 to VG100 as defined in ISO 3448.

Abstract: Provided is a vacuum pump oil which contains a mineral oil (A) having a temperature gradient ?|?*| of complex viscosity between two points of t (° C.) and t?10(° C.) (where ?15?t??10), as measured using a rotary rheometer at an angular velocity of 6.3 rad/s, of 10 Pa·s/° C. or less, and one or more compounds selected from a phenol-based compound (B) and an amine-based compound (C), and which has a viscosity index of less than 160. The vacuum pump oil has a good ultimate vacuum degree and is excellent in water separability, oxidation stability and shear stability, and is therefore applicable to various applications.

Abstract: Provided is a lubricant composition for a refrigerator having the following characteristics: the composition being used for a refrigerator using a refrigerant having a specific structure such as an unsaturated fluorinated hydrocarbon compound serving as a refrigerant having a low global warming potential and usable particularly in current air-conditioning system for cars; the composition having excellent stability as well as excellent compatibility with the refrigerant; the composition including a base oil containing a polyoxyalkylene glycol derivative as a main component and 1 to 20% by mass of a monoepoxy compound based on the total amount of the composition; and the refrigerator using a refrigerant containing at least one kind of fluorine-containing organic compound selected from compounds represented by the molecular formula (A) CpOqFrRs or including a combination of the fluorine-containing organic compound and a saturated fluorinated hydrocarbon compound.

Abstract: A lubricating oil composition for an air compressor according to the present invention contains a synthetic base oil, and one or more amine-based antioxidants selected from the group consisting of asymmetric diphenylamine-based compounds, phenylnaphthylamine-based compounds, asymmetric dinaphthylamine-based compounds, dialkyl monophenylamine-based compounds and dialkyl mononaphthylamine-based compounds.

Abstract: A lubricating oil composition for a rotary compressor capable of imparting high extreme pressure property while maintaining high oxidation stability is provided by mixing, in (a) a base oil, (b) an antioxidant and (c) a dithiophosphate ester compound represented by the formula (I) in an amount of 0.05% by mass or more and less than 2.0% by mass based on the total composition.

Abstract: A lubricating oil composition for an air compressor according to the present invention contains a synthetic base oil, and one or more amine-based antioxidants selected from the group consisting of asymmetric diphenylamine-based compounds, phenylnaphthylamine-based compounds, asymmetric dinaphthylamine-based compounds, dialkyl monophenylamine-based compounds and dialkyl mononaphthylamine-based compounds.

Abstract: A lubricating oil composition for refrigerator including a base oil and an acid scavenger, and a compressor using the composition are provided, where the acid scavenger is a polyalkylene glycol derivative represented by a formula (1) as follows: R1—[(OR2)e—OR3]f??(1) and the base oil is at least one compound selected from a group consisting of polyvinyl ether, polyalkylene glycol and an ether-base compound represented by a formula (2) as follows, Ra-[(ORb)n-(X)—(ORc)k]x-Rd??(2) where meanings of respective signs are as described in the specification.

Abstract: A lubricating oil composition for refrigerator is provided by adding base oil with biphenols selected from 4,4?-methylenebis(2,6-di-t-butyl-phenol), 2?2-methylenebis(4-methyl-6-t-butylphenol), 2,2?-methylenebis(4-ethyl-6-t-butylphenol) and 4,4?-butylidenebis(3-methyl-6-t-butylphenol).

Abstract: A lubricating oil composition for refrigerator is formed by adding an organic compound that includes a double bond in the molecule such as ?-olefin or conjugated diene to a base oil. Capable of being stably used for a long time in the presence of oxygen, the lubricating oil composition for refrigerator according to the invention is suitable for an open-type car air-conditioner, an electric driven car air-conditioner, a gas heat pump, an air conditioning device, a refrigerator, a vending machine, a showcase, various hot-water supply systems or a heating/cooling system.

Abstract: Provided is a lubricating oil composition for a refrigerator, the refrigerator using a refrigerant which has a low global warming potential and is applicable to, in particular, current car air conditioning systems or the like, that is, the refrigerant including at least one kind of fluorine-containing organic compounds selected from compounds represented by the following molecular formula (A) or including a combination of the fluorine-containing organic compound and a saturated fluorinated hydrocarbon compound, CpOqFrRs??(A) where: R represents Cl, Br, I, or H; p represents an integer of 1 to 6, q represents an integer of 0 to 2, r represents an integer of 1 to 14, and s represents an integer of 0 to 13; and provided that, when q represents 0, p represents 2 to 6 and one or more carbon-carbon unsaturated bonds are included in molecules, in which a base oil contained in the composition includes as a main component a polyvinyl ether derivative having a hydroxyl value of 17 mgKOH/g or less.

Abstract: Provided is a lubricating oil composition for a refrigerator, the refrigerator using a refrigerant which has a low global warming potential and is applicable to, in particular, current car air conditioning systems or the like, that is, the refrigerant including at least one kind of fluorine-containing organic compounds selected from compounds represented by the following molecular formula (A) or including a combination of the fluorine-containing organic compound and a saturated fluorinated hydrocarbon compound, CpOqFrRs??(A) where: R represents Cl, Br, I, or H; p represents an integer of 1 to 6, q represents an integer of 0 to 2, r represents an integer of 1 to 14, and s represents an integer of 0 to 13; and provided that, when q represents 0, p represents 2 to 6 and one or more carbon-carbon unsaturated bonds are included in molecules, in which the composition comprises a base oil including as a main component a polyvinyl ether-based compound having an alkylene glycol unit, or a polyoxyalkylene glycol unit