Ester for refrigerator oil, base oil for refrigerator oil, refrigerator oil, and working fluid composition

Abstract

An ester for refrigerating machine oil comprising: a first ester that is an ester of a polyhydric alcohol and a fatty acid having 6 to 9 carbon atoms; a second ester that is an ester of pentaerythritol and a fatty acid; and a third ester that is an ester of pentaerythritol, a dicarboxylic acid, and a fatty acid, wherein both the fatty acid constituting the second ester and the fatty acid constituting the third ester are mixed fatty acids comprising at least one selected from the group consisting of branched butanoic acid, branched pentanoic acid, and linear pentanoic acid, and either branched octanoic acid or branched nonanoic acid.

Dependencies are inferred from the claim text.