The present invention relates to heat transfer compositions comprising refrigerant, lubricant and stabilizer, wherein the refrigerant comprises from about 10% by weight to 100% by weight of trifluoroiodomethane (CF.sub.3I), and wherein said lubricant comprises polyol ester (POE) lubricant and/or polyvinyl ether (PVE) lubricant, and wherein said stabilizer comprises at least one stabilizing compound according to the following Formula I:

##STR00001##

where each R.sup.1 is independently an epoxy terminated ethoxy, propoxy or butoxy group.

The present invention relates to heat transfer compositions comprising refrigerant, lubricant and stabilizer, wherein the refrigerant comprises from about 10% by weight to 100% by weight of trifluoroiodomethane (CF.sub.3I), and wherein said lubricant comprises polyol ester (POE) lubricant and/or polyvinyl ether (PVE) lubricant, and wherein said stabilizer comprises at least one stabilizing compound according to the following Formula I:

##STR00001##

where each R.sup.1 is independently an epoxy terminated ethoxy, propoxy or butoxy group.

A working fluid composition for a refrigerating machine, containing: a refrigerant containing trifluoroiodometbane; and a refrigerating machine oil containing a polyol ester and a hindered phenol compound, wherein a content of the hindered phenol compound is 0.6 to 10% by mass based on a total amount of the refrigerating machine oil.

A working fluid composition for a refrigerating machine, containing: a refrigerant containing trifluoroiodometbane; and a refrigerating machine oil containing a polyol ester and a hindered phenol compound, wherein a content of the hindered phenol compound is 0.6 to 10% by mass based on a total amount of the refrigerating machine oil.

The present invention provides a refrigerating machine oil composition comprising an ester-based base oil, an epoxy compound, and a carbodiimide compound, the refrigerating machine oil composition being used with a refrigerant containing a fluoropropene in a refrigerating machine comprising a member containing polyethylene terephthalate and/or a member containing hydrogenated acrylonitrile butadiene rubber.

The present invention provides a refrigerating machine oil composition comprising an ester-based base oil, an epoxy compound, and a carbodiimide compound, the refrigerating machine oil composition being used with a refrigerant containing a fluoropropene in a refrigerating machine comprising a member containing polyethylene terephthalate and/or a member containing hydrogenated acrylonitrile butadiene rubber.

The present invention provides a refrigerating machine oil comprising: a base oil; a compound represented by the following formula (1):

##STR00001##

wherein R.sup.1 and R.sup.2 each independently represent a monovalent hydrocarbon group, R.sup.3 represents a divalent hydrocarbon group and R.sup.4 represents a hydrogen atom or a monovalent hydrocarbon group; and an epoxy compound.

The present invention provides a refrigerating machine oil comprising: a base oil; a compound represented by the following formula (1):

##STR00001##

wherein R.sup.1 and R.sup.2 each independently represent a monovalent hydrocarbon group, R.sup.3 represents a divalent hydrocarbon group and R.sup.4 represents a hydrogen atom or a monovalent hydrocarbon group; and an epoxy compound.

The present invention provides a grease composition or a lubricating oil composition which is capable of effectively preventing hydrogen brittleness-caused peeling from occurring on a rolling surface of a rolling bearing, is excellent in durability in a high temperature and speed operation, and can be used for a long time. A grease-packed bearing (1) has an inner ring (2), an outer ring (3), and a plurality of rolling elements (4). A sealing member (6) for sealing a grease composition (7) is provided at openings (8a) and (8b) disposed at both axial ends of the inner ring (2) and the outer ring (3). The grease composition (7) includes a base grease composed of a base oil and a thickener and an additive added to the base grease. The additive contains at least one compound selected from among plant-derived polyphenolic compounds and compounds formed by decomposition thereof. The above-described compounds include tannin, gallic acid, ellagic acid, chlorogenic acid, caffeic acid, curcumin, quercetin, and quinic acid.

The present invention is able to provide a lubricating oil composition for compression refrigerating machine having excellent thermal/chemical stability even when used for a compression refrigerating machine using a saturated fluorinated hydrocarbon refrigerant having a low carbon number and a low global warming potential, by using a refrigerant containing a saturated fluorinated hydrocarbon having from 1 to 3 carbon atoms, which uses, as a base oil, an oxygen-containing organic compound composed of at least one member selected from a polyoxyalkylene glycol, a polyvinyl ether, a copolymer of a poly(oxy)alkylene glycol and a polyvinyl ether, a copolymer of a poly(oxy)alkylene glycol monoether and a polyvinyl ether, and a polyol ester, each having a hydroxyl value of not more than 15 mgKOH/g.