Compositions, systems and methods for introducing lubricants, and additives, that are designed to work with environmentally friendly refrigerants into vehicle heat management systems including passenger compartment air conditioning (A/C) systems are disclosed. Methods for charging lubricants and specific additives using environmentally desirable (low GWP) refrigerant or refrigerant blend compositions into an environmentally friendly system, such as a system that uses HFO-1234yf, are also disclosed.

To provide a composition for a heat cycle system having favorable lubricating properties and comprising a working fluid for heat cycle which has a low global warming potential and which can replace R410A and a heat cycle system employing the composition. A composition for a heat cycle system comprising a working fluid for heat cycle containing trifluoroethylene, and a refrigerant oil (for example, an ester refrigerant oil, an ether refrigerant oil, a polyglycol refrigerant oil or a hydrocarbon refrigerant oil), and a heat cycle system employing the composition for a heat cycle system.

Disclosed is a method of lubricating a gas engine using a lubricant including at least one mineral base oil and at least one ester selected from among the polyol esters. The composition includes at least 50% by weight of mineral base oil and at least 5% by weight of polyol ester relative to the total weight of the lubricant composition.

The present invention provides a viscosity index improver having an excellent viscosity index improving effect, a lubricant composition having excellent low-temperature viscosity in which the viscosity reduction due to long-term use is small, and a method for producing the lubricant composition. A viscosity index improver of the present invention contains a copolymer (A) containing, as monomer units, an alkyl (meth)acrylate (a) whose alkyl group contains 5 or more carbon atoms, and an alkyl (meth)acrylate (b) whose alkyl group contains 1 to 4 carbon atoms, wherein the alkyl group of the alkyl (meth)acrylate (a) whose alkyl group contains 5 or more carbon atoms has a molar-average carbon number (Q) of 29 or more, and the alkyl (meth)acrylate (b) whose alkyl group contains 1 to 4 carbon atoms is contained as a monomer unit in an amount of 38 to 75% by weight based on the weight of the copolymer (A).

A method for extending performance or service life of a lubricating oil in an engine or other mechanical component lubricated with the lubricating oil by using as the lubricating oil a formulated oil. The formulated oil has a composition including a lubricating oil base stock as a major component, and at least one microencapsulated lubricating oil additive, as a minor component. The at least one microencapsulated lubricating oil additive includes an encapsulating material (e.g., polymeric matrix) and a core material (e.g., at least one lubricating oil additive) encapsulated by the encapsulating material. A method of improving solubility, compatibility and/or dispersion of lubricating oil additives in a lubricating oil base stock. A method for controlling release of a lubricating oil additive into a lubricating oil. A lubricating oil having a composition including a lubricating oil base stock as a major component, and at least one microencapsulated lubricating oil additive, as a minor component.

This disclosure provides low viscosity, low volatility aryl ether compounds represented by formula (1): ##STR00001##
and represented by formula (2): ##STR00002##
wherein R.sub.1 is the same or different and is a linear or branched alkyl group having from 1 to 20 carbon atoms; R.sub.2 is the same or different and is hydrogen or an alkyl group having from 1 to 4 carbon atoms; and n is the same or different and is a value from 0 to 8. This disclosure also provides processes for producing the aryl ether compounds, lubricating oil basestocks and lubricating oils containing one or more of the aryl ether compounds, and a method for improving one or more of solubility and dispersancy of polar additives and/or sludge in a lubricating oil by using as the lubricating oil a formulated oil containing one or more of the aryl ether compounds.

This disclosure provides low viscosity, low volatility aryl ether compounds represented by the formula: ##STR00001## This disclosure also provides processes for producing the aryl ether compounds, lubricating oil basestocks and lubricating oils containing one or more of the aryl ether compounds, and a method for improving one or more of solubility and dispersancy of polar additives and/or sludge in a lubricating oil by using as the lubricating oil a formulated oil containing one or more of the aryl ether compounds.

The present invention provides a refrigerating machine oil containing an ester base oil obtained from pentaerythritol and mixed fatty acids of a fatty acid having 8 carbon atoms and a fatty acid having 9 carbon atoms, wherein a ratio of a weight average molecular weight Mw to a number average molecular weight Mn, Mw/Mn, of the ester base oil is 1.06 to 1.20, and used with a mildly flammable hydrofluorocarbon refrigerant.

A lubricant composition including a binuclear molybdenum compound (A) and a trinuclear molybdenum compound (B), wherein these compounds are included in a range represented by (molybdenum of the binuclear molybdenum compound (A)):(molybdenum of the trinuclear molybdenum compound (B))=99.98:0.02 to 95:5 as a mass ratio.

A motor configured to power an electric or hybrid vehicle, comprising a lubricant oil composition including a polyalkylene glycol (PAG) base oil, at least one of a poly-alpha-olefin (PAO) and an ester, and an additive package that includes at least a sulfur-based extreme pressure agent.