The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 09, 1993
Filed:
Jan. 31, 1991
Masaaki Fukuda, Ohi, JP;
Hirotaka Tomizawa, Ohi, JP;
Mitsuo Ohta, Ohi, JP;
Hideki Osaka, Ohi, JP;
Satoshi Ogano, Ohi, JP;
Takehisa Satoh, Ohi, JP;
Kenji Ashibe, Ohi, JP;
Takeshi Nomura, Ohi, JP;
Tonen Corporation, Tokyo, JP;
Abstract
The lubricating oil for refrigerator according to the present invention is a lubricating oil for refrigerator using 1,1,1,2-tetrafluoroethane refrigerant. Having esters as base oil, its viscosity range is between 2-30 mm/s at 100.degree.C. By adding esters alone or by adding esters having different viscosity to esters base oil, or by adding polymer, the viscosity is adjusted to obtain the lubricating oil suitable for various types of refrigerators. The lubricating oil thus obtained has excellent compatibility with 1,1,1,2-tetrafluoroethane refrigerant, which is an alternative to freon, and has low hygroscopic property and high heat-resistant property. By reducing the total acid number to 0.05 mg KOH/g or less, the corrosion-resistant property and insulating property of lubricating oil are not decreased, and the lubricating oil for refrigerator having having high refrigerant stability, hydrolytic stability and insulating property can be obtained. Further, by adding sulfur type anti-wear agent, the better anti-wear effect of the lubricating oil can be obtained on iron/aluminum contact portion in the refrigerator.