| 摘要 |
PURPOSE:To obtain a refrigerator oil composition having excellent insulating properties, especially useful for a freezing system having a closed type compressor in an excellent operation efficiency by dissolving an additive in a solvent, dissolving in a base oil and then removing the solvent. CONSTITUTION:Pentaerythritol is conventionally esterified with 2-ethylhexanoic acid in the presence of a catalyst such as titanium tetrabutyrate. The prepared reaction product is mixed with potassium hydroxide to neutralize the catalyst and purified by water washing with distilled water to give a base oil of an ester oil. Besides, triphenyl phosphate as an additive is dissolved in a solvent such as toluene at room temperature to give a 40% solution. The solution is added to the base oil of an ester oil so that the amount of triphenyl phosphate becomes 2.0wt.% and uniformly dissolved at room temperature. Then the solvent is distilled away by vacuum distillation to give the refrigerator oil composition having excellent insulating properties in excellent operation efficiency. |
