Refrigerator oils for use with chlorine-free fluorocarbon refrigerants

A fluid composition for use in refrigerators, which consists of a chlorine-free fluorocarbon refrigerant and a refrigerator oil, said refrigerator oil consists of as a base oil a pentaerythritol ester of formula (1)

• wherein R1-R4 are identical with or different from each other and are each a member selected from the group consisting of straight-chain alkyl groups having 3 to 11 carbon atoms, branched-chain alkyl groups having 3 to 15 carbon atoms and cycloalkyl groups having 6 to 12 carbon atoms, the number of straight-chain alkyl groups being present in a concentration of not more than 60% of the total number of alkyl groups, and a is an integer of 1 to 3;
• at least one conventional oil selected from the group consisting of paraffinic mineral oils, naphthenic mineral oils, poly α-olefins and alkylbenzenes;
• 0.1 to 5% by weight based on the total amount of said refrigerator oil of at least one epoxy compound selected from the group consisting of phenylglycidyl ether epoxy compounds, alkylphenylglycidyl ether epoxy compounds, glycidyl ester epoxy compounds and epoxidized fatty acid monoesters, said base oil has a pour point not higher than −10° C. and a kinematic viscosity of 2 to 150 cSt at 100° C.;
• and at least one additive consisting of a member selected from the group consisting of phenol antioxidants, amine antioxidants, wear resistant additives, extreme pressure agents, oiliness improvers, antifoaming agents, and metal inactivators.

A fluid composition for use in refrigerators, which consists of a chlorine-free fluorocarbon refrigerant and a refrigerator oil, said refrigerator oil consists of as a base oil a pentaerythritol ester of formula (1)

• wherein R1-R4 are identical with or different from each other and are each a member selected from the group consisting of straight-chain alkyl groups having 3 to 11 carbon atoms, branched-chain alkyl groups having 3 to 15 carbon atoms and cycloalkyl groups having 6 to 12 carbon atoms, the number of straight-chain alkyl groups being present in a concentration of not more than 60% of the total number of alkyl groups, and a is an integer of 1 to 3;
• at least one conventional oil selected from the group consisting of paraffinic mineral oils, naphthenic mineral oils, polyα-olefins and alkylbenzenes;
• 0.1 to 5% by weight based on the total amount of said refrigerator oil of at least one epoxy compound selected from the group consisting of phenylglycidyl ether epoxy compounds, alkylphenylglycidyl ether epoxy compounds, glycidyl ester epoxy compounds and epoxidized fatty acid monoesters, said base oil has a pour point not higher than −10° C. and a kinematic viscosity of 2 to 150 cSt at 100° C.;
• and at least one phosphorus compound selected from the group consisting of phosphoric esters, acid phosphoric esters, amine salts of acid phosphoric esters, chlorinated phosphoric esters, and phosphorous esters.

A fluid composition for use in refrigerators which consists of a chlorine-free fluorocarbon refrigerant and a refrigerator oil, said refrigerator oil consists of as a base oil a pentaerythritol ester of formula (1)

• wherein R1-R4 are identical with or different from each other and are each a member selected from the group consisting of straight-chain alkyl groups having 3 to 11 carbon atoms, branched-chain alkyl groups having 3 to 15 carbon atoms and cycloalkyl groups having 6 to 12 carbon atoms, the number of straight-chain alkyl groups being present in a concentration of not more than 60% of the total number of alkyl groups, and a is an integer of 1 to 3;
• 0.1% to 5% by weight based on the total amount of said refrigerator oil of at least one epoxy compound selected from the group consisting of phenylglycidyl ether epoxy compounds, alkylphenylglycidyl ether epoxy compounds, glycidyl ester epoxy compounds and epoxidized fatty acid monoesters, said base oil has a pour point not higher than −10° C. and a kinematic viscosity of 2 to 150 cSt at 100° C.;
• at least one phosphorus compound selected from the group consisting of phosphoric esters, acid phosphoric esters, amine salts of acid phosphoric esters, chlorinated phosphoric esters, and phosphorous esters;
• and at least one additive, said additive consisting of a member selected from the group consisting of phenol antioxidants, amine antioxidants, wear resistant additives, extreme pressure agents, oiliness improvers, antifoaming agents and metal inactivators.

A fluid composition for use in refrigerators which consists of a chlorine-free fluorocarbon refrigerant and a refrigerator oil, said refrigerator oil consists of as a base oil a pentaerythritol ester of formula (1)

• wherein R1-R4 are identical with or different from each other and are each a member selected from the group consisting of straight-chain alkyl groups having 3 to 11 carbon atoms, branched-chain alkyl groups having 3 to 15 carbon atoms and cycloalkyl groups have 6 to 12 carbon atoms, the number of straight-chain alkyl groups being present in a concentration of not more than 60% of the total number of alkyl groups, and a is an integer of 1 to 3;
• at least one conventional oil selected from the group consisting of paraffinic mineral oils, naphthenic mineral oils, polyα-olefins and alkylbenzenes;
• 0.1 to 5% by weight based on the total amount of said refrigerator oil of at least one epoxy compound selected from the group consisting of phenylglycidyl ether epoxy compounds, alkylphenylglycidyl ether epoxy compounds, glycidyl ester epoxy compounds and epoxidized fatty acid monoesters, said base oil has a pour point not higher than −10° C. and a kinematic viscosity of 2 to 150 cSt at 100° C.;
• at least one phosphorus compound selected from the group consisting of phosphoric esters, acid phosphoric esters, amine salts of acid phosphoric esters, chlorinated phosphoric esters, and phosphorous esters;
• and at least one additive, said additive consisting of a member selected from the group consisting of phenol antioxidants, amine anti-oxidants, wear resistant additives, extreme pressure agents, oiliness improvers, antifoaming agents and metal inactivators.