Refrigerating machine oil composition

• US 20030166478A1
• Filed: 01/23/2003
• Published: 09/04/2003
• Est. Priority Date: 07/24/2000
• Status: Active Grant

• Current Assignee: Nippon Oil Corporation (ENEOS Holdings, Inc.)
• Original Assignee: Nippon Oil Corporation (ENEOS Holdings, Inc.)
• Inventors: Shimomura, Yuji, Takigawa, Katsuya
• Granted Patent: US 7,045,490 B2
• Time in Patent Office: Days
• US Class Current: 508/304
• CPC Class Codes: C10M 105/42 Complex esters, i.e. compounds containing at least three esterified carboxyl groups and derived from the combination of at least three different types of the following five types of compound: monohydroxy compounds, polyhydroxy compounds, monocarboxylic acids, polycarboxylic acids and hydroxy carboxylic acids
• CPC Class Codes: C10M 171/008 Lubricant compositions compatible with refrigerants

Abstract

A refrigerating machine oil composition according to the invention comprises an alicyclic polycarboxylic acid ester compound obtained from the following compounds (a) to (c):

(a) an alicyclic polycarboxylic acid having an alicyclic ring and two or more carboxyl groups, or its derivative, wherein at least two of the carboxyl groups are bonded to mutually adjacent carbon atoms on the alicyclic ring;

(b) a compound with two or more hydroxyl groups or its derivative; and

(c) a compound with one hydroxyl group or its derivative.

It can be used together with HFC refrigerants and natural refrigerants such as carbon dioxide and hydrocarbons, to provide a satisfactory balance between all of the properties of lubricity, miscibility with refrigerants, heat and hydrolytic stability and electric insulating property.

Claims

1. A refrigerating machine oil composition comprising an alicyclic polycarboxylic acid ester compound obtained from the following compounds (a) to (c):

(a) an alicyclic polycarboxylic acid having an alicyclic ring and two or more carboxyl groups, or its derivative, wherein at least two of the carboxyl groups are bonded to mutually adjacent carbon atoms on the alicyclic ring;

(b) a compound with two or more hydroxyl groups or its derivative; and

(c) a compound with one hydroxyl group or its derivative.

2. A refrigerating machine oil composition according to claim 1, wherein the number of carboxyl groups of compound (a) is 2, and the number of hydroxyl groups of compound (b) is 2.

3. A refrigerating machine oil composition according to claim 1, wherein compound (c) is a mixture of

at least one type of monohydric alcohol selected from the group consisting of aliphatic monohydric alcohols of 1-5 carbons and

at least one type of monohydric alcohol selected from the group consisting of aliphatic monohydric alcohols of 6-18 carbons.

4. A refrigerating machine oil composition according to claim 1, which further comprises at least one selected from the group consisting of phosphoric acid esters, acidic phosphoric acid esters, amine salts of acidic phosphoric acid ester, chlorinated phosphoric acid esters and phosphorous acid esters.

5. A refrigerating machine oil composition according to claim 1, which further comprises at least one selected from the group consisting of phenylglycidyl ether-type epoxy compounds, alkylglycidyl ether-type epoxy compounds, glycidyl ester-type epoxy compounds, allyloxirane compounds, alkyloxirane compounds, alicyclic epoxy compounds, epoxidized fatty acid monoesters and epoxidized vegetable oils.