To provide a composition for a heat cycle system, which comprises a working fluid for heat cycle which has a low global warming potential and high stability, and which can replace R410A, and a heat cycle system employing the composition. A composition for a heat cycle system, which comprises a working fluid for heat cycle containing trifluoroethylene, and a stabilizer for preventing deterioration of the working fluid for heat cycle, such as an oxidation resistance-improving agent, a heat resistance-improving agent or a metal deactivator, and a heat cycle system employing the composition for a heat cycle system.

The refrigerating machine oil according to the present invention contains a lubricating base oil having a kinematic viscosity at 40° C. of 10 mm.sup.2/s or less, and an oiliness agent containing at least one selected from the group consisting of an ester oiliness agent and an ether oiliness agent.

A refrigerating machine oil according to the present invention contains a lubricating base oil and alkylated hydroxyanisole, and a working fluid composition for a refrigerating machine according to the present invention contains the refrigerating machine oil and a refrigerant.

A lubricant composition comprises a lubricant and a stabilizer. The stabilizer comprises a first epoxide group and a second functional group selected from the group consisting of (i) a second epoxide group; (ii) an aliphatic carbon-carbon multiple bond conjugated with a second carbon-carbon multiple bond; (iii) an aliphatic carbon-carbon multiple bond conjugated with an electron withdrawing group; and (iv) an aliphatic carbon-carbon multiple bond conjugated with an aromatic group. A heat transfer composition comprises a lubricant composition as described above and a haloalkane, such as an iodoalkane (e.g., trifluoroiodomethane).

Aspects described herein generally relate to methods of making a phosphono paraffin comprising forming a reaction mixture by mixing a haloparaffin, a phosphite, and sodium iodide. Methods comprise heating the reaction mixture to form the phosphono paraffin. Aspects described herein further relate to a phosphono paraffin represented by formula (I):

##STR00001##

wherein each instance of R.sup.1 is independently

##STR00002##

wherein each instance of R.sup.2 and R.sup.3 is independently linear or branched C.sub.1-20 alkyl, C.sub.1-20 cycloalkyl, or aryl; the number of instances where R.sup.1 is

##STR00003##

of formula (I) is between about 2 and about 8; and n is an integer between 4 and 22.

The present invention provides a method for producing a refrigerating machine oil, comprising blending a hydrocarbyl hydrogen phosphite having an acid value of 100 mgKOH/g or less with a lubricating base oil or an oil composition containing a lubricating base oil, and a refrigerating machine oil obtained by the method.

To provide a composition for a heat cycle system, which comprises a working fluid for heat cycle which has a low global warming potential and high stability, and which can replace R410A, and a heat cycle system employing the composition.

A composition for a heat cycle system, which comprises a working fluid for heat cycle containing trifluoroethylene, and a stabilizer for preventing deterioration of the working fluid for heat cycle, such as an oxidation resistance-improving agent, a heat resistance-improving agent or a metal deactivator, and a heat cycle system employing the composition for a heat cycle system.

The present invention provides a refrigerating machine oil containing a lubricating base oil, a dialkyl hydrogen phosphite having two alkyl groups having 1 to 12 carbon atoms in the molecule, and an epoxy compound.

The present invention is to provide a refrigeration cycle apparatus that has a low GWP of 750 or less and low flammability and that maintains performance and safety for an extended period of time. The refrigeration cycle apparatus includes a compressor (300) that compresses a refrigerant, a condenser that condenses the refrigerant compressed by the compressor (300), a pressure reducer that reduces a pressure of the refrigerant condensed by the condenser, and an evaporator that evaporates the refrigerant reduced in pressure by the pressure reducer. The refrigerant is a mixed refrigerant which contains difluoromethane, pentafluoroethane, and trifluoroiodomethane and which has a global warming potential of 750 or less and a vapor pressure at 25° C. of 1.1 MPa or more and 1.8 MPa or less. The compressor (300) is a sealed electric compressor in which a refrigerator oil to lubricate a sliding portion is charged. The refrigerator oil is polyol ester oil and has a water content of 300 ppm by weight or less.

A lubricant additive for introduction into an AC/R system to improve lubricant miscibility and performance in the AC/R system.