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.

An additive for a lubricating composition includes an ionic tetrahedral borate compound which includes a cation and a tetrahedral borate anion having a boron atom, the boron atom has at least one aliphatic bidentate di-oxo ligand. The cation may be selected to provide detergent and/or dispersant and/or antioxidant properties to a lubricating composition.

To provide a composition for a heat cycle system with which a HCFO or a CFO can more stably lubricate, and a heat cycle system employing the composition. A composition for a heat cycle system comprising a working fluid for heat cycle containing at least one compound selected from predetermined HCFO and CFO, and a mixed refrigeration oil obtained by mixing a naphthenic mineral oil and other predetermined refrigeration oil, wherein the mixed refrigeration oil has a kinematic viscosity at 40° C. of 300 mm.sup.2/s or lower, a mixed composition 1 of the working fluid for heat cycle and the mixed refrigeration oil at a concentration of the working fluid for heat cycle of 10 mass % has a viscosity at 60° C. of 10 mPa.Math.s or higher, and a mixed composition 2 of the working fluid for a heat cycle system and the mixed refrigeration oil at a concentration of the mixed refrigeration oil of 5 mass % has a two phase separation temperature of 0° C. or lower, and a heat cycle system, which employs the composition for a heat cycle system.

The use of polyalkylenyl succinic anhydrides to stabilise an additive concentrate which includes a salicylate detergent and a nitrogen-free ashless organic friction modifier.

The use of berated dispersant, preferably in combination with polyalkylenyl succinic anhydrides, to stabilise an additive concentrate which includes a salicylate detergent and a nitrogen-free ashless organic friction modifier.

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.

A polyalkylene glycol having an end-group of the general formula: ##STR00001## in which each R.sup.2 independently represents a hydroxyl, alkyl, alkenyl, aryl, heteroaryl, benzyl, or polyalkylene glycol group, and each R.sup.3 independently represents a hydroxyl, alkyl, alkenyl, aryl, heteroaryl, benzyl, or polyalkylene glycol group; m is 0, 1, 2, 3, 4, 5 or 6; and n is 0, 1, 2 or 3. A lubricating oil composition comprising this polyalkylene glycol. A refrigerant composition comprising this polyalkylene glycol. A method of lubricating moving parts of an industrial or automotive system comprising applying a composition to the parts, wherein the composition comprises this polyalkylene glycol.

A lubricating composition comprises an amide and at least one additive. The amide is the reaction product of a secondary, branched amine and a carboxylic acid. The carboxylic acid may be a monocarboxylic acid or a dicarboxylic acid, including dimer acid. The amide is hydrolytically stable, and may be used to increase the hydrolytic stability of the lubricant composition. Alternatively, the amide may be used to increase the additive solubility or detergency of the lubricant composition.

A lubricant formulation which is effective to remove or prevent carbon deposits in internal combustion engines has a solvency as defined by aniline point from about 20 to about 115, a volatility (as measured by NOACK) of less than 15%, an oxidative stability (as measured by PDSC) of above 40 minutes and a base oil viscosity of above 2 and below 10 cSt. The lubricant formulation can be formed from a blend of Group III, IV and V lubricants, in particularly polyalphaolefins, alkylated naphthalenes and polar Group V base stocks such as polyol esters. The carbon deposits can be removed from the engine piston by simply running the engine with the lubricant for one required cycle, or can be used continuously in the engine to prevent buildup.

The present disclosure relates to a lubricant composition comprising a lubricant, a first ionic liquid which is soluble in polyalphaolefin and a second ionic liquid which is insoluble in polyalphaolefin. By using the two different ionic liquids, the technical properties of the lubricant compositions can be improved.