Inside a sealed container (101) of a refrigerant compressor (100), lubricating oil (103) having a kinematic viscosity at 40 C. of 0.1 mm.sup.2/S to 5.1 mm.sup.2/S is stored, and an electric element (106) and a compression element (107) are accommodated. The compression element (107) is provided with, as a shaft part, a crankshaft (108) comprising a main shaft (109) and an eccentric shaft (110), and as bearing parts, a main bearing (114) that axially supports the main shaft (109) and an eccentric bearing (119) that axially supports the eccentric shaft (110). At least one surface of the main shaft (109) and the eccentric shaft (110) is subjected to a surface treatment, e.g., formation of an oxide film, having a hardness equal to or greater than that of a bearing part (the main bearing (114) or the eccentric bearing (119)). Satisfactory reliability in sliding parts can thereby be achieved even if lubricating oil having lower viscosity is used.

Inside a sealed container (101) of a refrigerant compressor (100), lubricating oil (103) having a kinematic viscosity at 40 C. of 0.1 mm.sup.2/S to 5.1 mm.sup.2/S is stored, and an electric element (106) and a compression element (107) are accommodated. The compression element (107) is provided with, as a shaft part, a crankshaft (108) comprising a main shaft (109) and an eccentric shaft (110), and as bearing parts, a main bearing (114) that axially supports the main shaft (109) and an eccentric bearing (119) that axially supports the eccentric shaft (110). At least one surface of the main shaft (109) and the eccentric shaft (110) is subjected to a surface treatment, e.g., formation of an oxide film, having a hardness equal to or greater than that of a bearing part (the main bearing (114) or the eccentric bearing (119)). Satisfactory reliability in sliding parts can thereby be achieved even if lubricating oil having lower viscosity is used.

Provided is a lubricating oil comprising: (a) a major amount of an oil of lubricating viscosity, (b) a dispersant polymethacrylate (DPMA) VII, (c) a non-dispersant ethylene-based olefin copolymer viscosity index improver, (d) a magnesium containing detergent; wherein the lubricating oil composition is substantially free of molybdenum containing element. Also provided is a method for improving friction and reducing wear in an internal combustion engine using said engine lubricating oil composition.

Provided is a lubricating oil comprising: (a) a major amount of an oil of lubricating viscosity, (b) a dispersant polymethacrylate (DPMA) VII, (c) a non-dispersant ethylene-based olefin copolymer viscosity index improver, (d) a magnesium containing detergent; wherein the lubricating oil composition is substantially free of molybdenum containing element. Also provided is a method for improving friction and reducing wear in an internal combustion engine using said engine lubricating oil composition.

Provided are: an environment-friendly synthetic resin cage that uses a 100% biomass raw material and therefore aims for carbon neutrality while having performance as a bearing in a conventional process; and a rolling bearing incorporating said cage. A crown-type cage for holding a plurality of rolling elements incorporated between an inner ring and an outer ring is produced with a polyamide resin composition containing a 100% biomass-derived raw material with a reinforcing material contained therein, wherein the raw material is polyamide 410 and 10-40 wt % of the reinforcing material is contained therein.

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.

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.

A method for improving wear control, while maintaining or improving energy efficiency, in an engine or other mechanical component lubricated with a lubricating oil, by using as the lubricating oil a formulated oil. The formulated oil includes at least one lubricating oil base stock having one or more liquid crystals represented by the formula:

R1-(A).sub.m-Y(B).sub.nR2

wherein R1 and R2 are the same or different and are a substituted or unsubstituted, hydrocarbon, alkoxy or alkylthio group having from 2 to 24 carbon atoms; A and B are the same or different and are a cycloaliphatic group or aromatic group, provided at least one of A and B is an aromatic group; Y is a covalent bond, CH2-CH2-, CHCH, OCOO, CO, CSO, CSS, CS, O, S, SO, SO2-, CH2O, OCH2O, NO, ONO2, or CN; and m and n are independently 0, 1, 2 or 3. The lubricating oil base stock has a kinematic viscosity of 2 cSt to 200 cSt at 40 C., and 1 cSt to 25 cSt at 100 C. Also, this disclosure relates to low traction/energy efficient liquid crystal base stocks containing liquid crystals.

A composition for enhanced heat transfer fluid performance. The composition includes at least one base heat transfer fluid. The at least one base heat transfer fluid undergoes one or more phase changes in a heat transfer process. The heat transfer process includes a heated zone and/or a cooled zone. The one or more phase changes increase heat removal from the heated zone and/or increase heat rejection in the cooled zone, as compared to heat removal from a heated zone and/or heat rejection in a cooled zone of a heat transfer process having a base heat transfer fluid that does not undergo one or more phase changes. The base heat transfer fluids can exhibit liquid crystal behavior (e.g., heat transfer fluids having nematic, smectic or discotic liquid crystals). A method for conducting heat transfer in a heating and/or cooling system using the compositions comprising the base heat transfer fluids.

A method for improving friction and wear control, while maintaining or improving energy efficiency, in an engine or other mechanical component lubricated with a lubricating oil, by using as the lubricating oil a formulated oil. The formulated oil has a composition including at least one lubricating oil base stock. The at least one lubricating oil base stock includes one or more liquid crystals, wherein the one or more liquid crystals are represented by the formula:

A(R1).sub.n

wherein A is a mono-ring or a multi-ring aromatic group, R1 is the same or different and is a substituted or unsubstituted, hydrocarbon, alkoxy, or alkylthio group having from 2 to 24 carbon atoms, and n is a value from 1 to 12. The lubricating oil base stock has a kinematic viscosity of 2 cSt to 200 cSt at 40 C., as determined according to ASTM D445, and a kinematic viscosity of 1 cSt to 25 cSt at 100 C., as determined according to ASTM D445.