The present disclosure relates to a synthetic vegetable oil and an environmental-friendly flame-retardant hydraulic oil composition including the same, and a preparation method thereof, and provides a method of preparing a glycerin-ester-based lubricating base oil through a catalyst-free and rinsing-free process, a glycerin-ester-based lubricating base oil that is a synthetic vegetable oil obtained by the method, and an environmental-friendly flame-retardant hydraulic oil composition that contains the glycerin-ester-based lubricating base oil and that is capable of reducing electricity consumption by 7 to 8% compared to mineral oil-based lubricating oils due to excellent flame retardancy (with self-extinguishing function) and lubricity.

The present disclosure relates to a synthetic vegetable oil and an environmental-friendly flame-retardant hydraulic oil composition including the same, and a preparation method thereof, and provides a method of preparing a glycerin-ester-based lubricating base oil through a catalyst-free and rinsing-free process, a glycerin-ester-based lubricating base oil that is a synthetic vegetable oil obtained by the method, and an environmental-friendly flame-retardant hydraulic oil composition that contains the glycerin-ester-based lubricating base oil and that is capable of reducing electricity consumption by 7 to 8% compared to mineral oil-based lubricating oils due to excellent flame retardancy (with self-extinguishing function) and lubricity.

A lubricating oil composition includes at least one base oil selected from the group consisting of a mineral oil-based lubricating oil, a synthetic oil-based lubricating oil, and a mixed oil thereof, zinc dialkyldithiophosphate X represented by Formula (1), and an acid phosphate ester amine salt Y represented by Formula (2), in which a content P.sub.X of the X is from 0.06% by mass to 0.08% by mass in terms of phosphorus concentration with respect to a total mass of the lubricating oil composition, and a content P.sub.Y of the Y is from 0.015% by mass to 0.025% by mass in terms of phosphorus concentration with respect to the total mass of the lubricating oil composition.

A lubricating oil composition includes at least one base oil selected from the group consisting of a mineral oil-based lubricating oil, a synthetic oil-based lubricating oil, and a mixed oil thereof, zinc dialkyldithiophosphate X represented by Formula (1), and an acid phosphate ester amine salt Y represented by Formula (2), in which a content P.sub.X of the X is from 0.06% by mass to 0.08% by mass in terms of phosphorus concentration with respect to a total mass of the lubricating oil composition, and a content P.sub.Y of the Y is from 0.015% by mass to 0.025% by mass in terms of phosphorus concentration with respect to the total mass of the lubricating oil composition.

The present invention provides a refrigerating machine oil comprising a lubricating base oil and at least one selected from the group consisting of an amine salt of phosphonic acid and an amine salt of phosphonic acid monoester, and a method for producing the same.

The present invention provides a refrigerating machine oil comprising a lubricating base oil and at least one selected from the group consisting of an amine salt of phosphonic acid and an amine salt of phosphonic acid monoester, and a method for producing the same.

A shock absorber oil composition of the invention includes a base oil: (A) at least one of phosphate, amine phosphate salt, phosphite and amine phosphite salt; (B) an amide compound; and (C) an N-substituted derivative of sarcosine.

A shock absorber oil composition of the invention includes a base oil: (A) at least one of phosphate, amine phosphate salt, phosphite and amine phosphite salt; (B) an amide compound; and (C) an N-substituted derivative of sarcosine.

An ionic liquid composition having the following generic structural formula:

##STR00001##

wherein Z is N or P, and R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are independently selected from hydrogen atom and hydrocarbon groups having one to four carbon atoms with optional interconnection to form a cyclic group that includes Z, and wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are all hydrocarbon groups when Z is P, and X.sup.− is a phosphorus-containing or carboxylate anion, particularly an organophosphate, organophosphonate, or organophosphinate anion, or a thio-substituted analog thereof containing hydrocarbon groups with at least three carbon atoms. Also described are lubricant compositions comprising the above ionic liquid and a base lubricant, wherein the ionic liquid is dissolved in the base lubricant. Further described are methods for applying the ionic liquid or lubricant composition onto a mechanical device for which lubrication is beneficial, with resulting improvement in friction reduction, wear rate, and/or corrosion inhibition.

The invention relates to a grease composition having a base oil and a thickener that includes hydrophilic metal oxide particles and one or more esters which contain one or more unsaturated C—C bonds and/or at least one OH group. The hydrophilic metal oxide particles have a BET specific surface area of at least 10 m.sup.2/g and at least 80% of the hydrophilic metal oxide particles have a particle size in the range of from 5 nm to 900 μm. The amount of the thickener is in the range of from 0.1-40% by weight, based on the total weight of the grease composition. The invention further relates to methods for manufacturing the grease compositions, and the use of the grease compositions for lubricating bearings, gears and couplings.