Working fluid composition for refrigerator, refrigeration oil, and method for producing same

• US 9,469,801 B2
• Filed: 02/28/2013
• Issued: 10/18/2016
• Est. Priority Date: 03/02/2012
• Status: Active Grant

• Current Assignee: JX Nippon Oil & Energy Corporation (ENEOS Holdings, Inc.)
• Original Assignee: JX Nippon Oil & Energy Corporation (ENEOS Holdings, Inc.)
• Inventors: Saito, Masanori, Okido, Takeshi, Sawada, Ken, Adegawa, Kuniko
• Primary Examiner(s): HARDEE, JOHN R
• Application Number:
  US14/381,829
• Publication Number:
  US 20150014575A1
• Time in Patent Office: 1,328 Days
• US Class Current: 1/1
• CPC Class Codes: C09K 2205/11 Ethers
• CPC Class Codes: C09K 2205/12 Hydrocarbons
• CPC Class Codes: C09K 5/042 comprising compounds containing carbon and hydrogen only
• CPC Class Codes: C10M 171/008 Lubricant compositions compatible with refrigerants
• CPC Class Codes: C10M 2203/1006 used as base material
• CPC Class Codes: C10M 2207/026 with tertiary alkyl groups
• CPC Class Codes: C10M 2207/042 Epoxides
• CPC Class Codes: C10M 2207/2835 used as base material
• CPC Class Codes: C10M 2207/301 used as base material
• CPC Class Codes: C10M 2209/1055 used as base material
• CPC Class Codes: C10M 2209/108 etherified
• CPC Class Codes: C10M 2215/064 Di- and triaryl amines
• CPC Class Codes: C10M 2215/086 Imides
• CPC Class Codes: C10M 2223/041 Triaryl phosphates
• CPC Class Codes: C10N 2020/011 Cloud point
• CPC Class Codes: C10N 2020/04 Molecular weight; Molecular weight distribution
• CPC Class Codes: C10N 2020/103 Containing Hydrocarbons
• CPC Class Codes: C10N 2030/02 Pour-point; Viscosity index
• CPC Class Codes: C10N 2030/06 Oiliness; Film-strength; Anti-wear; Resistance to extreme pressure
• CPC Class Codes: C10N 2030/08 Resistance to extreme temperature
• CPC Class Codes: C10N 2030/10 : Inhibition of oxidation, e.g. anti-oxidants
• CPC Class Codes: C10N 2030/70 : Soluble oils
• CPC Class Codes: C10N 2040/30 : Refrigerators lubricants or compressors lubricants

Abstract

A working fluid composition for a refrigerating machine of the present invention comprises: a refrigerating machine oil comprising a complex ester as a base oil; and a hydrocarbon refrigerant having 2 to 4 carbon atoms, the complex ester being obtainable by further esterifying, with at least one selected from a monohydric alcohol having 1 to 20 carbon atoms and a fatty acid having 2 to 20 carbon atoms, an ester intermediate obtained by reacting a neopentyl polyol with a dibasic acid, and having an acid value of 0.5 mgKOH/g or less, the refrigerating machine oil having a kinematic viscosity at 100° C. of 2 to 50 mm²/s.

Claims

1. A working fluid composition for a refrigerating machine, comprising:

a refrigerating machine oil comprising a complex ester as a base oil; and

a refrigerant consisting of at least one hydrocarbon refrigerant having 2 to 4 carbon atoms, wherein

the complex ester is a complex ester of neopentyl polyol, a dibasic acid, and a monohydric alcohol having 1 to 20 carbon atoms,

the complex ester has an acid value of 0.5 mgKOH/g or less, and

the refrigerating machine oil has a kinematic viscosity at 100°

C. of 2 to 50 mm²/s.

2. The working fluid composition for a refrigerating machine according to claim 1, wherein

the neopentyl polyol is at least one selected from neopentyl glycol, trimethylol propane, and pentaerythritol,

the dibasic acid is at least one selected from adipic acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid, and

the refrigerant is at least one selected from propane, butane, and isobutane.

3. The working fluid composition for a refrigerating machine according to claim 1, wherein the monohydric alcohol is at least one selected from linear alcohols having 4 to 18 carbon atoms, 2-ethyl hexanol, and 3,5,5,-trimethyl hexanol.

4. The working fluid composition for a refrigerating machine according to claim 1, wherein the complex ester is obtained by further esterifying, with the monohydric alcohol having 1 to 20 carbon atoms, an ester intermediate obtained by reacting the dibasic acid with trimethylol propane at a ratio of 1.5 moles or more and less than 3 moles of the dibasic acid per 1 mole of trimethylol propane.

5. The working fluid composition for a refrigerating machine according to claim 1, further comprising at least one additive selected from a hindered phenol compound, an aromatic amine compound, an epoxy compound, a carbodiimide, and a phosphoric acid ester,

wherein the total content of the additive is 0.05 to 5.0% by mass based on the total amount of the refrigerating machine oil.

6. The working fluid composition for a refrigerating machine according to claim 1, wherein the volume resistivity at 80°

C. of the refrigerating machine oil is 10¹¹ Ω

·

cm or more.

7. The working fluid composition for a refrigerating machine according to claim 1, wherein the refrigerant is propane.

8. A working fluid composition for a refrigerating machine, comprising:

a refrigerating machine oil comprising a complex ester as a base oil; and

a refrigerant consisting of at least one hydrocarbon refrigerant having 2 to 4 carbon atoms, wherein

the complex ester is obtained by further esterifying, with a monohydric alcohol having 1 to 20 carbon atoms, an ester intermediate obtained by reacting a neopentyl polyol with a dibasic acid,

the complex ester has an acid value of 0.5 mgKOH/g or less, and

the refrigerating machine oil has a kinematic viscosity at 100°

C. of 2 to 50 mm²/s.