Refrigerator oil and working fluid composition for refrigerator

Patent metadata

Field	Value
Publication number	US-11208608-B2
Application number	US-201716343226-A
Country	US
Kind code	B2
Filing date	Oct 20, 2017
Priority date	Oct 20, 2016
Publication date	Dec 28, 2021
Grant date	Dec 28, 2021

Abstract

In an aspect, the present invention provides a refrigerating machine oil comprising a poly(meth)acrylate as a base oil, wherein the poly(meth)acrylate comprises a hydrogenated poly(meth)acrylate, a content of a unit having a carbon-carbon double bond present at a terminal in the poly(meth)acrylate is 6% by mole or less relative to total units constituting the poly(meth)acrylate, and a kinematic viscosity at 40° C. of the hydrogenated poly(meth)acrylate is 1 to 1000 mm2/s, the refrigerating machine oil being used with a refrigerant comprising a refrigerant selected from difluoromethane, a mixture of difluoromethane and pentafluoroethane, a mixture of difluoromethane, pentafluoroethane, and 1, 1, 1, 2-tetrafluoroethane, a mixture of pentafluoroethane, 1, 1, 1, 2-tetrafluoroethane, and 1, 1, 1-trifluoroethane, an unsaturated hydrofluorocarbon, a hydrocarbon, and carbon dioxide.

First claim

The invention claimed is:

1. A working fluid composition for a refrigerating machine, comprising:
a refrigerating machine oil comprising
a base oil,
wherein the base oil comprises
poly(meth)acrylate comprised of a hydrogenated poly(meth)acrylate, a content of a unit having a carbon-carbon double bond present at a terminal in the poly(meth)acrylate is 6% by mole or less relative to total units constituting the poly(meth)acrylate, and a kinematic viscosity at 40° C. of the hydrogenated poly(meth)acrylate is 1 to 1000 mm 2 /s, wherein an amount of the hydrogenated poly(meth)acrylate is 30% by mass or less based on the total amount of the poly(meth)acrylate, and
an oil other than the hydrogenated poly(meth)acrylate; and

a refrigerant comprising a refrigerant selected from the group consisting of
a mixture of difluoromethane, pentafluoroethane, and 1,1,1,2-tetrafluoroethane,
an unsaturated hydrofluorocarbon, and
a hydrocarbon,

wherein
a mass ratio of the refrigerating machine oil/the refrigerant is from 2/100 to 400/100,
a content of the base oil is 80% by mass or more, based on the total amount of the refrigerating machine oil, and
the hydrogenated poly(meth)acrylate has a structural unit represented by the following formula (1):

wherein R 1 , R 2 , and R 3 represent a hydrogen atom or a hydrocarbon group, and R 4 is an alkyl group having 1 to 4 carbon atoms.

2. The working fluid composition for a refrigerating machine according to claim 1 , wherein the refrigerant comprises a mixture of difluoromethane, pentafluoroethane, and 1,1,1,2-tetrafluoroethane.

3. The working fluid composition for a refrigerating machine according to claim 1 , wherein the refrigerant comprises an unsaturated hydrofluorocarbon.

4. The working fluid composition for a refrigerating machine according to claim 1 , wherein the hydrocarbon group represented by R 4 in the formula (1) is an alkyl group having 2 carbon atoms.

5. The working fluid composition for a refrigerating machine according to claim 1 , wherein R 1 and R 2 in the formula (1) each are a hydrogen atom and R 3 in the formula (1) is a hydrogen atom or a methyl group.

6. The working fluid composition for a refrigerating machine according to claim 1 , wherein the average degree of polymerization of the hydrogenated poly(meth)acrylate is 3 to 20.

7. The working fluid composition for a refrigerating machine according to claim 3 , wherein the unsaturated hydrofluorocarbon is selected from the group consisting of 1,2,3,3,3-pentafluoropropene (HFO-1225ye), 1,3,3,3-tetrafluoropropene (HFO-1234ze), 2,3,3,3-tetrafluoropropene (HFO-1234yf), 1,2,3,3-tetrafluoropropene (HFO-1234ye), and 3,3,3-trifluoropropene (HFO-1243zf).

8. The working fluid composition for a refrigerating machine according to claim 1 , wherein the refrigerant comprises a hydrocarbon selected from the group consisting of methane, ethylene, ethane, propylene, propane (R290), cyclopropane, normal butane, isobutane, cyclobutane, methylcyclopropane, 2-methylbutane, and normal pentane.

9. The working fluid composition for a refrigerating machine according to claim 1 , wherein a mass ratio of the refrigerating machine oil/the refrigerant is from 2/100 to 30/70.

10. The working fluid composition for a refrigerating machine according to claim 1 , wherein a mass ratio of the refrigerating machine oil/the refrigerant is from 10/90 to 30/70.

11. A method for improving a compatibility of a working fluid composition for a refrigerating machine comprising,
(a) preparing a refrigerating machine oil comprising a base oil consisting of a poly(meth)acrylate, and
(b) mixing a refrigerant and the refrigerating machine oil, wherein the poly(meth)acrylate has a structural unit represented by the following formula

wherein R 1 and R 2 each are a hydrogen atom and R 3 be a hydrogen atom or a methyl group, and R 4 is an alkyl group having 1 to 10 carbons, and
a content of a unit having a carbon-carbon double bond present at a terminal in the poly(meth)acrylate is 6% by mole or less relative to total units constituting the poly(meth)acrylate;
an amount of the hydrogenated poly(meth)acrylate is 30% by mass or less based on the total amount of the poly(meth)acrylate; and
the refrigerant comprises at least one refrigerant selected from the group consisting of a mixture of difluoromethane, pentafluoroethane, and 1,1,1,2-tetrafluoroethane, a mixture of pentafluoroethane, 1,1,1,2-tetrafluoroethane, and 1,1,1-trifluoroethane, an unsaturated hydrofluorocarbon, and a hydrocarbon.

12. The method for improving a compatibility of a working fluid composition for a refrigerating machine according to claim 11 , wherein the refrigerant comprising a refrigerant selected from the group consisting of a mixture of difluoromethane, pentafluoroethane, and 1,1,1,2-tetrafluoroethane, an unsaturated hydrofluorocarbon, and a hydrocarbon;
the unsaturated hydrofluorocarbon is selected from the group consisting of 1,3,3,3-tetrafluoropropene (HFO-1234ze), and 2,3,3,3-tetrafluoropropene (HFO-1234yf), 1,2,3,3-tetrafluoropropene (HFO-1234ye); and
the hydrocarbon is selected from the group consisting of propane (R290), normal butane, isobutane, and 2-methylbutane.

13. The method for improving a compatibility of a working fluid composition for a refrigerating machine according to claim 11 , wherein a mass ratio of the refrigerating machine oil/the refrigerant is from 2/100 to 30/70.

14. A working fluid composition for a refrigerating machine, comprising
a refrigerant; and
a refrigerating machine oil comprising a base oil consisting of a poly(meth)acrylate,
wherein the refrigerant comprising a refrigerant selected from the group consisting of
a mixture of difluoromethane, pentafluoroethane, and 1,1,1,2-tetrafluoroethane,
an unsaturated hydrofluorocarbon, and
a hydrocarbon,
the unsaturated hydrofluorocarbon is selected from the group consisting of 1,3,3,3-tetrafluoropropene (HFO-1234ze), and 2,3,3,3-tetrafluoropropene (HFO-1234yf), 1,2,3,3-tetrafluoropropene (HFO-1234ye), and
the hydrocarbon is selected from the group consisting of propane (R290), normal butane, isobutane, and 2-methylbutane,
a mass ratio of the refrigerating machine oil/the refrigerant is from 2/100 to 400/100; and the poly(meth)acrylate has a structural unit represented by the following formula (1):

wherein R 1 and R 2 each are a hydrogen atom and R 3 be a hydrogen atom or a methyl group, and R 4 is an alkyl group having 1 to 10 carbons,
the poly(meth)acrylate contains a hydrogenated poly(meth)acrylate, and
a content of a unit having a carbon-carbon double bond present at a terminal in the poly(meth)acrylate is greater than 1% by mole and 6% by mole or less relative to total units constituting the poly(meth)acrylate.

15. The working fluid composition for a refrigerating machine according to claim 14 , wherein a mass ratio of the refrigerating machine oil/the refrigerant is from 2/100 to 30/70.

16. The working fluid composition for a refrigerating machine according to claim 14 , wherein a mass ratio of the refrigerating machine oil/the refrigerant is from 10/90 to 30/70.

17. The working fluid composition for a refrigerating machine

Assignees

• Eneos Corp

Inventors

• Yamaguchi Kentaro
• Tada Akira
• Nakajima Tatsuki
• Okido Takeshi
• Ogata Hidetoshi

Classifications

• C10M107/28 Primary

  containing monomers having an unsaturated radical bound to a carboxyl radical, e.g. acrylate · CPC title

• C09K2205/126

  Unsaturated fluorinated hydrocarbons · CPC title

• C09K5/042 Primary

  comprising compounds containing carbon and hydrogen only · CPC title

• C10N2020/101

  Containing Hydrofluorocarbons · CPC title

• C10N2040/30

  Refrigerators lubricants {or compressors lubricants} · CPC title