A working fluid filled in a refrigerant circulation system comprising a compressor, a condenser, an expansion mechanism, an evaporator, and an accumulator, the working fluid comprising: a refrigerant; and a refrigerating machine oil, wherein the refrigerant comprises a hydrocarbon refrigerant having 2 to 4 carbon atoms, the refrigerating machine oil has a mixed aniline point of 20 C. or higher and 50 C. or lower and a viscosity index of 110 or more, an amount of the refrigerant dissolved in the working fluid is 40% by mass or less under conditions of a temperature of 80 C. and an absolute pressure of 2.8 MPa, and the refrigerating machine oil has a kinematic viscosity at 10 C. of 200 mm.sup.2/s or more and 3000 mm.sup.2/s or less.

A working fluid filled in a refrigerant circulation system comprising a compressor, a condenser, an expansion mechanism, an evaporator, and an accumulator, the working fluid comprising: a refrigerant; and a refrigerating machine oil, wherein the refrigerant comprises a hydrocarbon refrigerant having 2 to 4 carbon atoms, the refrigerating machine oil has a mixed aniline point of 20 C. or higher and 50 C. or lower and a viscosity index of 110 or more, an amount of the refrigerant dissolved in the working fluid is 40% by mass or less under conditions of a temperature of 80 C. and an absolute pressure of 2.8 MPa, and the refrigerating machine oil has a kinematic viscosity at 10 C. of 200 mm.sup.2/s or more and 3000 mm.sup.2/s or less.

The invention relates to novel ester compounds of the general formula (I)

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to a process for preparation thereof and to the use thereof. These ester compounds may contain a mixture of at least two compounds of the general formula (I).

The present invention provides a cutting method comprising a cutting step of cutting a workpiece material with a cutting tool to thereby form a through-groove in the workpiece material, wherein in the cutting step, the through-groove is formed in the workpiece material by cutting the workpiece material with the cutting tool while contacting a cut-assisting lubricant with the contact portion of the cutting tool with the workpiece material and/or the contact portion of the workpiece material with the cutting tool, and the workpiece material comprises a fiber reinforced composite material.

The present invention provides a cutting method comprising a cutting step of cutting a workpiece material with a cutting tool to thereby form a through-groove in the workpiece material, wherein in the cutting step, the through-groove is formed in the workpiece material by cutting the workpiece material with the cutting tool while contacting a cut-assisting lubricant with the contact portion of the cutting tool with the workpiece material and/or the contact portion of the workpiece material with the cutting tool, and the workpiece material comprises a fiber reinforced composite material.

A lubricant composition improves a performance of reducing a formation of compressor deposit. The lubricant composition also ensures low temperature properties of the lubricant composition. The lubricant composition includes 14 mass % or more of a fraction having a boiling point of 500 C. to 550 C. and 5 mass % or more of a fraction having a boiling point of over 550 C.

A lubricant composition improves a performance of reducing a formation of compressor deposit. The lubricant composition also ensures low temperature properties of the lubricant composition. The lubricant composition includes 14 mass % or more of a fraction having a boiling point of 500 C. to 550 C. and 5 mass % or more of a fraction having a boiling point of over 550 C.

The invention relates to the use of an O/W emulsion, in particular a PIT emulsion, for lubricating conveyor belt systems in food industries as well as a lubricant concentrate based on an O/W emulsion, in particular a PIT emulsion, of wax esters.

The invention relates to the use of an O/W emulsion, in particular a PIT emulsion, for lubricating conveyor belt systems in food industries as well as a lubricant concentrate based on an O/W emulsion, in particular a PIT emulsion, of wax esters.

The working fluid composition for a refrigerating machine of the invention is characterized by comprising an ester of a polyhydric alcohol and a fatty acid with a content of a C5-C9 branched fatty acid of 50-100% by mole, and a fluoropropene refrigerant and/or trifluoroiodomethane refrigerant. The refrigerating machine oil of the invention is characterized by comprising an ester of a polyhydric alcohol and a fatty acid with a content of a C5-C9 branched fatty acid of 50-100% by mole, and by being used together with a fluoropropene refrigerant and/or trifluoroiodomethane refrigerant.