Lubricant oil composition for compression refrigerator

Patent metadata

Field	Value
Publication number	US-9790449-B2
Application number	US-201214130197-A
Country	US
Kind code	B2
Filing date	Jun 28, 2012
Priority date	Jul 1, 2011
Publication date	Oct 17, 2017
Grant date	Oct 17, 2017

Abstract

The present invention is able to provide a lubricating oil composition for compression refrigerating machine having excellent thermal/chemical stability even when used for a compression refrigerating machine using a saturated fluorinated hydrocarbon refrigerant having a low carbon number and a low global warming potential, by using a refrigerant containing a saturated fluorinated hydrocarbon having from 1 to 3 carbon atoms, which uses, as a base oil, an oxygen-containing organic compound composed of at least one member selected from a polyoxyalkylene glycol, a polyvinyl ether, a copolymer of a poly(oxy)alkylene glycol and a polyvinyl ether, a copolymer of a poly(oxy)alkylene glycol monoether and a polyvinyl ether, and a polyol ester, each having a hydroxyl value of not more than 15 mgKOH/g.

First claim

The invention claimed is:

1. A composition, comprising:
(i) a refrigerant consisting of difluoromethane R32; and
(ii) a lubricating composition consisting of
a base oil consisting of at least one selected from the group consisting of
a polyvinyl ether,
a copolymer of a poly(oxy)alkylene glycol and a polyvinyl ether, and
a copolymer of a poly(oxy)alkylene glycol monoether and a polyvinyl ether,
wherein each base oil has a hydroxyl value of not more than 15 mgKOH/g,

optionally from 0.01 to 5% by mass of an antioxidant, based on the total amount of the lubricating oil composition,
optionally from 0.005 to 10% by mass of an acid scavenger, based on the total amount of the lubricating oil composition, and
optionally at least one additive selected from the group consisting of an extreme pressure agent, an oiliness agent, a metal deactivator, and a defoaming agent.

2. The composition according to claim 1 , wherein the base oil comprises, as a major component, the polyvinyl ether, wherein the polyvinyl ether is a compound comprising a constituent unit of formula (II):

wherein:
each of R 4 , R 5 , and R 6 independently represents a hydrogen atom or a hydrocarbon group comprising from 1 to 8 carbon atoms;
R 7 represents a divalent hydrocarbon group comprising from 2 to 10 carbon atoms;
R 8 represents a hydrocarbon group comprising from 1 to 10 carbon atoms;
p represents a number of from 0 to 10 in terms of an average value thereof;
each of R 4 to R 8 is independent for every constituent unit; and
when plural R 7 Os are present, each of the plural R 7 Os is independent.

3. The composition according to claim 1 , wherein the lubricating oil composition comprises at least one of the antioxidant and the acid scavenger.

4. The composition according to claim 1 , wherein the base oil has a number average molecular weight of 300 or more and not more than 3,000.

5. The composition according to claim 1 , wherein the base oil has a viscosity index of 60 or more.

6. The composition according to claim 1 , wherein the lubricating oil composition comprises the at least one additive selected from the group consisting of the extreme pressure agent, the oiliness agent, the metal deactivator, and the defoaming agent.

7. The composition according to claim 1 , wherein a sliding portion of the compression refrigerating machine comprises an engineering plastic, an organic coating film, or an inorganic coating film.

8. The composition according to claim 7 , wherein the organic coating film is a polytetrafluoroethylene coating film; a polyimide coating film; a polyamide-imide coating film; or a thermosetting insulating film obtained by using a resin coating material comprising a resin base material, which comprises a polyhydroxy ether resin, a polysulfone-based resin, and a crosslinking agent.

9. The composition according to claim 7 , wherein the inorganic coating film is a graphite film, a diamond-like carbon film, a tin film, a chromium film, a nickel film, or a molybdenum film.

10. The composition according claim 1 , wherein the lubricating oil composition is suitable for use in a system, which is a car air conditioner, an electric car air conditioner, a gas heat pump, an air conditioner, a refrigerator, an automatic vending machine, a showcase, a hot water supply system, or a refrigerating/heating system.

11. The composition according to claim 10 , wherein the system has a water content of not more than 300 ppm by mass and a residual air partial pressure of not more than 10 kPa.

12. The composition according to claim 1 wherein the base oil consists of the polyvinyl ether.

13. The composition according to claim 1 , wherein the base oil consists of the copolymer of a poly(oxy)alkylene glycol and a polyvinyl ether.

14. The composition according to claim 1 , wherein the base oil consists of the copolymer of a poly(oxy)alkylene glycol monoether and a polyvinyl ether.

15. The composition according to claim 1 , wherein the base oil consists of the polyvinyl ether, and the polyvinyl ether has a hydroxyl value of not more than 6 mgKOH/g.

16. The composition according to claim 1 , wherein the antioxidant is a phenol antioxidant, and wherein the acid scavenger a glycidyl ether acid scavenger.

17. The composition according to claim 2 , wherein the polyvinyl ether having a constituent unit of formula (II) is a polymer or a copolymer in which an amount of a constituent unit wherein all of R 4 , R 5 , and R 6 are a hydrogen atom, p is 0, and R 8 is an ethyl group is from 50 to 100% by mole, and an amount of a constituent unit wherein all of R 4 , R 5 , and R 6 are a hydrogen atom, p is 0, and R 8 is an alkyl group having 3 or 4 carbon atoms is from 0 to 50% by mole.

18. The composition according to claim 2 , wherein the polyvinyl ether having a constituent unit of formula (II) is a compound in which a proportion of the constituent unit wherein R 8 is an ethyl group is 100% by mole.

19. The composition according to claim 1 , wherein the base oil consists of the polyvinyl ether, and the polyvinyl ether has a hydroxyl value of not more than 3 mgKOH/g.

Assignees

• Matsumoto Tomoya
• Idemitsu Kosan Co

Inventors

• Matsumoto Tomoya

Classifications

• C10N2040/30

  Refrigerators lubricants {or compressors lubricants} · CPC title

• C10N2030/08

  Resistance to extreme temperature · CPC title

• C10N2020/101

  Containing Hydrofluorocarbons · CPC title

• C10N2030/12

  Inhibition of corrosion, e.g. anti-rust agents or anti-corrosives · CPC title

• C10N2030/52

  Base number [TBN] · CPC title