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.

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 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.

A phenol derivative of the present invention has a structure as represented by the formula (I):

##STR00001##

The functional groups are defined in the description. The phenol derivative can be used as the antioxidant in lubricating oil, lubricating grease, plastic, rubber, or can be used as the base oil of the lubricating oil and the lubricating grease and the antiwear additive of the lubricating oil and the lubricating grease.

A phenol derivative of the present invention has a structure as represented by the formula (I):

##STR00001##

The functional groups are defined in the description. The phenol derivative can be used as the antioxidant in lubricating oil, lubricating grease, plastic, rubber, or can be used as the base oil of the lubricating oil and the lubricating grease and the antiwear additive of the lubricating oil and the lubricating grease.

Drilling fluid compositions and methods for using drilling fluid compositions are provided with enhanced lubricating properties that include an aqueous-based fluid, one or more drilling fluid additives, and a lubricating additive. The lubricating additive may be an epoxidized α-olefin and the drilling fluid may include the lubricating additive in an amount ranging from about 1 ppb to about 20 ppb. Methods for using the drilling fluid compositions may further include mixing an aqueous base fluid with one or more drilling fluid additives and a lubricating additive, wherein the lubricating additive includes epoxidized α-olefin and the drilling fluid may include the lubricating additive in an amount ranging from about 0.5 ppb to about 20 ppb, and introducing the drilling fluid to a subterranean formation.

Provided are a heat source machine and an operation method of the same that employ predetermined solutions by using a predetermined refrigerating machine oil that can suppress deterioration of the refrigerating machine oil and viscosity reduction when a refrigerant is dissolved in the refrigerating machine oil. In the heat source machine (10) of the present disclosure, a compressor (11), a condenser (12), an expansion valve (13), and an evaporator (14) are connected to each other via main pipes (L.sub.1 to L.sub.8) to form a refrigerant circulation circuit configured to circulate a refrigerant, and the refrigerant circulation circuit is filled with HFO-1336mzz (Z) as a refrigerant. The heat source machine includes a refrigerating machine oil supply unit (15) configured to supply a refrigerating machine oil to the compressor (11), the refrigerating machine oil supply unit (15) includes a storage unit (15a) storing the refrigerating machine oil, the refrigerating machine oil includes an ester-based base oil having a dynamic viscosity of 100 mm.sup.2/s to 180 mm.sup.2/s at 40 C. and an epoxy-based acid scavenger at a mass of 0.1% by mass to 6% by mass with respect to a total mass of the refrigerating machine oil, and the machine design temperature is 130 C. or higher and 225 C. or lower.

Provided are a heat source machine and an operation method of the same that employ predetermined solutions by using a predetermined refrigerating machine oil that can suppress deterioration of the refrigerating machine oil and viscosity reduction when a refrigerant is dissolved in the refrigerating machine oil. In the heat source machine (10) of the present disclosure, a compressor (11), a condenser (12), an expansion valve (13), and an evaporator (14) are connected to each other via main pipes (L.sub.1 to L.sub.8) to form a refrigerant circulation circuit configured to circulate a refrigerant, and the refrigerant circulation circuit is filled with HFO-1336mzz (Z) as a refrigerant. The heat source machine includes a refrigerating machine oil supply unit (15) configured to supply a refrigerating machine oil to the compressor (11), the refrigerating machine oil supply unit (15) includes a storage unit (15a) storing the refrigerating machine oil, the refrigerating machine oil includes an ester-based base oil having a dynamic viscosity of 100 mm.sup.2/s to 180 mm.sup.2/s at 40 C. and an epoxy-based acid scavenger at a mass of 0.1% by mass to 6% by mass with respect to a total mass of the refrigerating machine oil, and the machine design temperature is 130 C. or higher and 225 C. or lower.

A phenol derivative of the present invention has a structure as represented by the formula (I): ##STR00001##
The functional groups are defined in the description. The phenol derivative can be used as the antioxidant in lubricating oil, lubricating grease, plastic, rubber, or can be used as the base oil of the lubricating oil and the lubricating grease and the antiwear additive of the lubricating oil and the lubricating grease.

A phenol derivative of the present invention has a structure as represented by the formula (I): ##STR00001##
The functional groups are defined in the description. The phenol derivative can be used as the antioxidant in lubricating oil, lubricating grease, plastic, rubber, or can be used as the base oil of the lubricating oil and the lubricating grease and the antiwear additive of the lubricating oil and the lubricating grease.