A composition contains a polyalkylene glycol and a fatty amine ethoxylate, the fatty amine ethoxylate having non-cyclic structure of structure (I). Where R is a linear, non-cyclic carbon-containing group with that is free of nitrogen, x and y are selected from a group consisting of zero and positive values provided that the sum of x and y are in a range of 8-20. ##STR00001##

The present invention provides a refrigerating machine oil comprising a base oil; a sulfide compound; and an orthophosphoric acid ester, wherein a content of the sulfide compound is 0.01 to 2.0% by mass and a content of the orthophosphoric acid ester is 0.1 to 5.0% by mass, based on a total amount of the refrigerating machine oil, and the refrigerating machine oil having a kinematic viscosity at 40 C. of 3 to 500 mm.sup.2/s.

Provided is a lubricant including a silicon-containing ionic liquid represented by formula (1). ##STR00001##
(In the formula, R.sup.1 represents an alkyl group having 1 to 10 carbon atoms, R.sup.2 represents an alkyl group having 8 to 20 carbon atoms, and R.sup.3 represents an alkyl group having 1 to 8 carbon atoms. Herein, it is provided that the number of carbon atoms in R.sup.2 is greater than the number of carbon atoms in R.sup.1.)

A method for improving oxidative stability of a lubricating oil in a diesel engine, in which biodiesel fuel is used with diesel fuel in the diesel engine, by using as the lubricating oil a formulated oil. The formulated oil has a composition including at least one Group V lubricating oil base stock. The at least one Group V lubricating oil base stock is present in an amount from 1 to 75 weight percent, based on the total weight of the lubricating oil. Oxidative stability is improved in a diesel engine lubricated with the lubricating oil, as compared to oxidative stability achieved in a diesel engine lubricated with a lubricating oil not having the at least one Group V lubricating oil base stock, as determined by a CEC L-109-16 Bio-Diesel Oxidation Bench test. The lubricating oils are useful as passenger vehicle engine oil (PVEO) products or commercial vehicle engine oil (CVEO) products.

The present invention provides a refrigerating machine oil comprising a base oil; a sulfide compound; and an orthophosphoric acid ester, wherein a content of the sulfide compound is 0.01 to 2.0% by mass and a content of the orthophosphoric acid ester is 0.1 to 5.0% by mass, based on a total amount of the refrigerating machine oil, and the refrigerating machine oil having a kinematic viscosity at 40? C. of 3 to 500 mm.sup.2/s.

Provided is a lubricant including a silicon-containing ionic liquid represented by formula (1).

##STR00001##

(In the formula, R.sup.1 represents an alkyl group having 1 to 10 carbon atoms, R.sup.2 represents an alkyl group having 8 to 20 carbon atoms, and R.sup.3 represents an alkyl group having 1 to 8 carbon atoms. Herein, it is provided that the number of carbon atoms in R.sup.2 is greater than the number of carbon atoms in R.sup.1.)

The present invention provides a refrigerating machine oil comprising a base oil; a sulfide compound; and an orthophosphoric acid ester, wherein a content of the sulfide compound is 0.01 to 2.0% by mass and a content of the orthophosphoric acid ester is 0.1 to 5.0% by mass, based on a total amount of the refrigerating machine oil, and the refrigerating machine oil having a kinematic viscosity at 40? C. of 3 to 500 mm.sup.2/s.

A synergistic mixture comprising from 1 to 99.9% by weight of compounds having structural elements (I) ##STR00001##
in which the free valencies on the oxygen atom and on the nitrogen atom may be combined to form a five-, six- or seven-membered ring and the benzene ring may also bear substituents at one or more of the free positions, and from 0.1 to 99% by weight of sulfur-containing organic compounds with antioxidant action. This synergistic mixture is suitable as a stabilizer for stabilizing inanimate organic material, especially mineral oil products and fuels, against the action of light, oxygen and heat.

A synergistic mixture comprising from 1 to 99.9% by weight of compounds having structural elements (I) ##STR00001##
in which the free valencies on the oxygen atom and on the nitrogen atom may be combined to form a five-, six- or seven-membered ring and the benzene ring may also bear substituents at one or more of the free positions, and from 0.1 to 99% by weight of sulfur-containing organic compounds with antioxidant action. This synergistic mixture is suitable as a stabilizer for stabilizing inanimate organic material, especially mineral oil products and fuels, against the action of light, oxygen and heat.