JP5435859B2 - Refrigerator oil and working fluid composition for refrigerator - Google Patents

Description

  The present invention relates to a refrigerator oil and a working fluid composition for a refrigerator.

  Due to the problem of ozone depletion in recent years, CFC (chlorofluorocarbon) and HCFC (hydrochlorofluorocarbon), which have been used as refrigerants in conventional refrigeration equipment, are subject to regulation, and HFC (hydrofluorocarbon) is used as a refrigerant instead. It is being done.

  When CFC or HCFC is used as a refrigerant, mineral oil or hydrocarbon oil such as alkylbenzene has been suitably used as the refrigeration oil. However, when the refrigerant is changed, the refrigeration oil used in the coexistence is compatible with the refrigerant, Refrigerating machine oil needs to be developed for each refrigerant in order to exhibit unpredictable behaviors such as lubricity, melt viscosity with refrigerant, and thermal and chemical stability. Therefore, as a refrigerating machine oil for HFC refrigerant, for example, polyalkylene glycol (see Patent Document 1), ester (see Patent Document 2), carbonate (see Patent Document 3), polyvinyl ether (see Patent Document 4) Etc. are being developed.

  Among HFC refrigerants, HFC-134a, which is standardly used as a refrigerant for car air conditioners, has zero ozone depletion potential (ODP), but has a high global warming potential (GWP). ing. Therefore, there is an urgent need to develop a refrigerant that replaces HFC-134a.

  Under such a background, as an alternative to HFC-134a, whether both ODP and GWP are very small, nonflammable, and thermodynamic properties that are a measure of refrigerant performance are almost equivalent to HFC-134a More than that, the use of refrigerants of fluoropropenes has been proposed. Furthermore, the use of a mixed refrigerant of fluoropropene and saturated hydrofluorocarbon, saturated hydrocarbon having 3 to 5 carbon atoms, dimethyl ether, carbon dioxide, bis (trifluoromethyl) sulfide or trifluoroiodomethane is also proposed ( (See Patent Document 5).

Also usable with fluoropropene refrigerant or mixed refrigerant of fluoropropene and saturated hydrofluorocarbon, saturated hydrocarbon having 3 to 5 carbon atoms, dimethyl ether, carbon dioxide, bis (trifluoromethyl) sulfide or trifluoroiodomethane. Refrigerating machine oils include mineral oils, alkylbenzenes, polyalphaolefins, polyalkylene glycols, monoesters, diesters, polyol esters, phthalate esters, alkyl ethers, ketones, carbonate esters, and polyvinyl ethers. Refrigerating machine oil using the above has been proposed (see Patent Documents 5 to 7).
Japanese Patent Laid-Open No. 02-242888 Japanese Patent Laid-Open No. 03-200895 Japanese Patent Laid-Open No. 03-217495 Japanese Patent Laid-Open No. 06-128578 International Publication WO2006 / 094303 Pamphlet JP-T-2006-512426 International Publication WO2005 / 103190 Pamphlet

  As described in Patent Documents 5, 6, and 7, in a refrigeration system using a fluoropropene refrigerant, mineral oil used in CFC and HCFC, hydrocarbons such as alkylbenzene, and polyphenol used in HFC. It is considered that any refrigerating machine oil such as alkylene glycol, polyol ester, and polyvinyl ether is applicable. However, according to the study by the present inventors, refrigerant compatibility cannot be achieved at a high level simply by diverting these conventional refrigeration oils as they are to the system.

  The present invention has been made in view of such circumstances, and in a refrigerating system using a fluoropropene refrigerant, a refrigerating machine oil and a working fluid composition for a refrigerating machine that can achieve refrigerant compatibility at a high level. The purpose is to provide.

As a result of intensive studies to achieve the above object, the present inventors have realized a refrigerating machine oil having sufficient compatibility with a refrigerant in the presence of a specific fluoropropene refrigerant by using a specific polyvinyl ether. The present inventors have found that this can be done and have completed the present invention.

［式中、Ｒ^１，Ｒ^２及びＲ^３は同一でも異なっていてもよく、それぞれ水素原子又は炭素数１〜８の炭化水素基を示し、Ｒ^４は炭素数１〜１０の二価の炭化水素基又は炭素数２〜２０の二価のエーテル結合酸素含有炭化水素基を示し、Ｒ^５は炭素数１〜２０の炭化水素基を示し、ｍは前記ポリビニルエーテルについてのｍの平均値が０〜１０となるような数を示し、Ｒ^１〜Ｒ^５は構造単位毎に同一であっても異なっていてもよく、一の構造単位においてｍが２以上である場合には、複数のＲ^４Ｏは同一でも異なっていてもよい。］ That is, the present invention relates to a polyvinyl ether having a structural unit represented by the following general formula (1) and having a carbon / oxygen molar ratio of 4.0 to 5.8, and 1,3,3,3-tetra providing tetrafluoropropene and 2,3,3,3 refrigerant working fluid composition at least one tetrafluoropropene refrigerant selected from tetrafluoropropene, characterized by containing for.

[Wherein R ¹ , R ² and R ³ may be the same or different and each represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms; R ⁴ is a divalent carbon atom having 1 to 10 carbon atoms; A hydrogen group or a divalent ether-bonded oxygen-containing hydrocarbon group having 2 to 20 carbon atoms, R ⁵ represents a hydrocarbon group having 1 to 20 carbon atoms, and m is an average value of m for the polyvinyl ether of 0. And R ^{1 to} R ⁵ may be the same or different for each structural unit. When m is 2 or more in one structural unit, a plurality of R ⁴ O may be the same or different. ]

  Moreover, this invention contains the polyvinyl ether which has a structural unit represented by the said General formula (1), and whose carbon / oxygen molar ratio is 4.0-5.8, and is used with a fluoro propene refrigerant | coolant. A refrigerating machine oil characterized by the above is provided.

Refrigerant working fluid composition of the present invention, as fluoropropene refrigerants, 1, 3,3,3-tetrafluoropropene (HFC-1234ze) and 2,3,3,3-tetrafluoropropene (HFC-1234yf) containing a pressurized et least one selected.

The working fluid composition for a refrigerating machine of the present invention, 1,3,3,3 least one tetrafluoropropene refrigerant selected from tetrafluoropropene and 2,3,3,3-tetrafluoropropene (hereinafter , "Refrigerant (A)") may be used alone, saturated hydrofluorocarbon, hydrocarbon having 3 to 5 carbon atoms, dimethyl ether, carbon dioxide, bis (trifluoromethyl) sulfide, and trifluoroiodomethane It may further contain at least one selected from refrigerants (hereinafter referred to as “refrigerant (B)”).

Furthermore, in the mixed refrigerant in the refrigerant (A) and refrigerant (B), as the fluoropropene refrigerant, 1, 3,3,3-tetrafluoropropene (HFC-1234ze) and 2,3,3,3-tetrafluoro is at least one selected from propene (HFC-1234yf);
Examples of saturated hydrofluorocarbons include difluoromethane (HFC-32), pentafluoroethane (HFC-125), 1,1,2,2-tetrafluoroethane (HFC-134), 1,1,1,2-tetrafluoro. Ethane (HFC-134a), 1,1-difluoroethane (HFC-152a), fluoroethane (HFC-161), 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea), 1 1,1,1,2,3,3-hexafluoropropane (HFC-236ea), 1,1,1,3,3,3-hexafluoropropane (HFC-236fa), 1,1,1,3,3 A small amount selected from pentafluoropropane (HFC-245fa) and 1,1,1,3,3-pentafluorobutane (HFC-365mfc) Kutomo one is preferred;
The hydrocarbon having 3 to 5 carbon atoms is preferably at least one selected from propane, normal butane, isobutane, 2-methylbutane and normal pentane.

  As described above, according to the present invention, it is possible to provide a refrigerating machine oil and a working fluid composition for a refrigerating machine that can achieve refrigerant compatibility at a high level.

  Hereinafter, preferred embodiments of the present invention will be described in detail.

［式中、Ｒ^１，Ｒ^２及びＲ^３は同一でも異なっていてもよく、それぞれ水素原子又は炭素数１〜８の炭化水素基を示し、Ｒ^４は炭素数１〜１０の二価の炭化水素基又は炭素数２〜２０の二価のエーテル結合酸素含有炭化水素基を示し、Ｒ^５は炭素数１〜２０の炭化水素基を示し、ｍは前記ポリビニルエーテルについてのｍの平均値が０〜１０となるような数を示し、Ｒ^１〜Ｒ^５は構造単位毎に同一であっても異なっていてもよく、一の構造単位においてｍが２以上である場合には、複数のＲ^４Ｏは同一でも異なっていてもよい。］ The refrigerating machine oil of the present invention comprises a polyvinyl ether having a structural unit represented by the following general formula (1) and a carbon / oxygen molar ratio of 4.0 to 5.8 (hereinafter referred to as “according to the present invention”). Polyvinyl ether ”)) and is used together with a fluoropropene refrigerant. The working fluid composition for a refrigerator according to the present invention is characterized by containing polyvinyl ether represented by the following general formula (1) and a fluoropropene refrigerant. Here, the working fluid composition for a refrigerator of the present invention includes an embodiment containing the refrigerator oil of the present invention and a fluoropropene refrigerant.

[Wherein R ¹ , R ² and R ³ may be the same or different and each represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms; R ⁴ is a divalent carbon atom having 1 to 10 carbon atoms; A hydrogen group or a divalent ether-bonded oxygen-containing hydrocarbon group having 2 to 20 carbon atoms, R ⁵ represents a hydrocarbon group having 1 to 20 carbon atoms, and m is an average value of m for the polyvinyl ether of 0. And R ^{1 to} R ⁵ may be the same or different for each structural unit. When m is 2 or more in one structural unit, a plurality of R ⁴ O may be the same or different. ]

R ¹ , R ² and R ³ in the general formula (1) may be the same as or different from each other, and each represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms. Specific examples of the hydrocarbon group having 1 to 8 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, and various types. Alkyl groups such as pentyl group, various hexyl groups, various heptyl groups, various octyl groups; cycloalkyl groups such as cyclopentyl group, cyclohexyl group, various methylcyclohexyl groups, various ethylcyclohexyl groups, various dimethylcyclohexyl groups; phenyl groups, various methyl groups Aryl groups such as phenyl group, various ethylphenyl groups, various dimethylphenyl groups; arylalkyl groups such as benzyl group, various phenylethyl groups, various methylbenzyl groups, and the like. As each of R ¹ , R ² and R ^3, a hydrogen atom is particularly preferable.

R ⁴ in the general formula (1) represents a divalent hydrocarbon group having 1 to 10 carbon atoms or a divalent ether bond oxygen-containing hydrocarbon group having 2 to 20 carbon atoms. Specific examples of the divalent hydrocarbon group having 1 to 10 carbon atoms include methylene group; ethylene group; phenylethylene group; 1,2-propylene group; 2-phenyl-1,2-propylene group; 3-propylene group; various butylene groups; various pentylene groups; various hexylene groups; various heptylene groups; various octylene groups; various nonylene groups; divalent aliphatic groups of various decylene groups, cyclohexane, methylcyclohexane, ethylcyclohexane, dimethylcyclohexane Alicyclic groups having two bonding sites to alicyclic hydrocarbons such as propylcyclohexane, various phenylene groups, various methylphenylene groups, various ethylphenylene groups, various dimethylphenylene groups, various naphthylene groups, etc. Aromatic hydrocarbon group, toluene; xylene; alkyl aromatics such as ethylbenzene An alkyl aromatic group having a monovalent bonding site in each of the alkyl group portion and the aromatic portion of hydrogen fluoride, xylene; an alkyl aromatic group having a bonding site in the alkyl group portion of a polyalkyl aromatic hydrocarbon such as diethylbenzene, etc. Can be mentioned. Among these, an aliphatic group having 2 to 4 carbon atoms is particularly preferable. Specific examples of the divalent ether-bonded oxygen-containing hydrocarbon group having 2 to 20 carbon atoms include methoxymethylene group; methoxyethylene group; methoxymethylethylene group; 1,1-bismethoxymethylethylene group; Preferred examples include -bismethoxymethylethylene group; ethoxymethylethylene group; (2-methoxyethoxy) methylethylene group; (1-methyl-2-methoxy) methylethylene group.

M in the general formula (1) represents a repeating number of ^{R 4} O, the average value of m for the polyvinyl ether according to the present invention is 0-10, preferably 0-5. In addition, when m is 2 or more in one structural unit, the plurality of R ⁴ Os may be the same or different.

R ⁵ in the general formula (1) represents a hydrocarbon group having 1 to 20 carbon atoms. Specific examples of the hydrocarbon group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, various pentyl groups, and various hexyl groups. , Various heptyl groups, various octyl groups, various nonyl groups, alkyl groups of various decyl groups, cyclopentyl groups, cyclohexyl groups, various methylcyclohexyl groups, various ethylcyclohexyl groups, various propylcyclohexyl groups, various dimethylcyclohexyl groups, etc. Aryl groups such as phenyl group, various methylphenyl groups, various ethylphenyl groups, various dimethylphenyl groups, various propylphenyl groups, various trimethylphenyl groups, various butylphenyl groups, various naphthyl groups, benzyl groups, various phenylethyl groups, Various methylbenzyl groups, Seed phenylpropyl group, etc. arylalkyl group various phenylbutyl groups. The R ^{1 to} R ⁵ may be the same or different for each structural unit. That is, the polyvinyl ether according to the present invention includes copolymers in which any or all of R ^{1 to} R ⁵ are different for each structural unit.

  Moreover, in the polyvinyl ether concerning this invention, the carbon / oxygen molar ratio needs to exist in the range of 4.2-5.8. If this molar ratio is less than 4.0, the hygroscopicity is high, and if it exceeds 5.8, the compatibility with fluoropropene decreases.

Further, in the polyvinyl ether according to the present invention, the number of repeating structural units represented by the general formula (1) (that is, the degree of polymerization) may be appropriately selected according to the desired kinematic viscosity. The kinematic viscosity at ° C. is preferably 5 to 1,000 mm ² / s, more preferably 7 to 300 mm ² / s.

  The polyvinyl ether according to the present invention may be a homopolymer having the same structural unit represented by the general formula (1) or a copolymer composed of two or more structural units. By using a copolymer, there is an effect that lubricity, insulation, hygroscopicity and the like can be further improved while satisfying compatibility. At this time, by selecting the kind of raw material monomer, the kind of initiator, and the ratio of the copolymer, the performance of the oil can be adjusted to the target level. Therefore, there is an effect that an oil agent can be freely obtained in accordance with requirements such as lubricity and compatibility that differ depending on the type of compressor, the material of the lubrication part, the refrigerating capacity, the type of refrigerant, and the like in the refrigeration system or the air conditioning system. The copolymer may be a block copolymer or a random copolymer.

Further, if polyvinyl ether according to the present invention is a copolymer, the copolymer, the structural units (1 and R ⁵ is represented by the general formula (1) is a hydrocarbon group having 1 to 3 carbon atoms -1) and a structural unit (1-2) represented by the above general formula (1) and R ⁵ is a hydrocarbon group having 3 to 20 carbon atoms, preferably 3 to 10 carbon atoms, more preferably 3 to 8 carbon atoms. It is preferable to contain. As R ⁵ in the structural unit (1-1), an ethyl group is particularly preferable, and as R ⁵ in the structural unit (1-2), an isobutyl group is particularly preferable. Furthermore, when the polyvinyl ether according to the present invention is a copolymer containing the structural units (1-1) and (1-2), the structural unit (1-1) and the structural unit (1-2) The molar ratio is preferably 5:95 to 95: 5, and more preferably 20:80 to 90:10. When the molar ratio deviates from the above range, the compatibility with the refrigerant becomes insufficient, and the hygroscopicity tends to increase.

［式中、Ｒ^６〜Ｒ^９は、互いに同一でも異なっていてもよく、それぞれ水素原子又は炭素数１〜２０の炭化水素基を示す。］ The polyvinyl ether according to the present invention may be composed only of the structural unit represented by the above general formula (1), but the copolymer further includes a structural unit represented by the following general formula (2). It may be a coalescence. In this case, the copolymer may be a block copolymer or a random copolymer.

[In formula, R < ⁶ > -R < ⁹ > may mutually be same or different, and shows a hydrogen atom or a C1-C20 hydrocarbon group, respectively. ]

Examples of the hydrocarbon group having 1 to 20 carbon atoms represented by R ⁶ to R ^9, may be mentioned the same as ^{R 5} in the general formula (1). R ^{6 to} R ⁹ may be the same or different for each structural unit.

The degree of polymerization of polyvinyl ether comprising a block or random copolymer having the structural unit represented by the general formula (1) and the structural unit represented by the general formula (2) is appropriately selected according to the desired kinematic viscosity. In general, the kinematic viscosity at a temperature of 40 ° C. is preferably 5 to 1,000 mm ² / s, more preferably 7 to 300 mm ² / s. Also in the case of this polyvinyl ether, the carbon / oxygen molar ratio needs to be in the range of 4.0 to 5.8. If the molar ratio is less than 4.0, the hygroscopicity is high, and if it exceeds 5.8, the compatibility with fluoropropene decreases.

［式中、Ｒ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５及びｍは、それぞれ一般式（１）中のＲ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５及びｍと同一の定義内容を示す。］ The polyvinyl ether according to the present invention can be produced by polymerization of a corresponding vinyl ether monomer and copolymerization of a corresponding hydrocarbon monomer having an olefinic double bond and a corresponding vinyl ether monomer. As the vinyl ether monomer corresponding to the structural unit represented by the general formula (1), a monomer represented by the following general formula (2) is suitable.

^{Wherein, R 1, R 2, R} 3, R 4, R 5 and m ^{is, R 1, R 2, R} 3, R 4, R 5 and the same definition as m, respectively in the general formula (1) Show the contents. ]

  Specific examples of the vinyl ether monomer represented by the general formula (3) include vinyl methyl ether; vinyl ethyl ether; vinyl n-propyl ether; vinyl isopropyl ether; vinyl n butyl ether; Vinyl-sec-butyl ether; vinyl-tert-butyl ether; vinyl-n-pentyl ether; vinyl-n-hexyl ether; vinyl-2-methoxyethyl ether; vinyl-2-ethoxyethyl ether; -1-methylethyl ether; vinyl-2-methoxy-2-methyl ether; vinyl-3,6-dioxaheptyl ether; vinyl-3,6,9-trioxadecyl ether; vinyl-1,4-dimethyl- 3,6-dioxaheptyl ester Ter; vinyl-1,4,7-trimethyl-3,6,9-trioxadecyl ether; vinyl-2,6-dioxa-4-heptyl ether; vinyl-2,6,9-trioxa-4-decyl ether 1-methoxypropene; 1-ethoxypropene; 1-n-propoxypropene; 1-isopropoxypropene; 1-n-butoxypropene; 1-isobutoxypropene; 1-sec-butoxypropene; 1-tert-butoxypropene; 2-methoxypropene; 2-ethoxypropene; 2-n-propoxypropene; 2-isopropoxypropene; 2-n-butoxypropene; 2-isobutoxypropene; 2-sec-butoxypropene; 2-tert-butoxypropene 1-methoxy-1-butene; 1-ethoxy-1-butene; 1-n- 1-isopropoxy-1-butene; 1-n-butoxy-1-butene; 1-isobutoxy-1-butene; 1-sec-butoxy-1-butene; 1-tert-butoxy-1 2-butene; 2-methoxy-1-butene; 2-ethoxy-1-butene; 2-n-propoxy-1-butene; 2-isopropoxy-1-butene; 2-n-butoxy-1-butene; Isobutoxy-1-butene; 2-sec-butoxy-1-butene; 2-tert-butoxy-1-butene; 2-methoxy-2-butene; 2-ethoxy-2-butene; 2-n-propoxy-2- 2-isopropoxy-2-butene; 2-n-butoxy-2-butene; 2-isobutoxy-2-butene; 2-sec-butoxy-2-butene; 2-tert-butoxy-2 -Butene and the like. These vinyl ether monomers can be produced by known methods.

［式中、Ｒ^６〜Ｒ^９は、それぞれ一般式（１）中のＲ^６〜Ｒ^９と同一の定義内容を示す。］ As the hydrocarbon monomer having an olefinic double bond corresponding to the structural unit represented by the general formula (2), a monomer represented by the following general formula (4) is preferably used.

^Wherein, R 6 to R ⁹ indicate respectively the same definition as ^R 6 to R ⁹ in the general formula (1). ]

  Examples of the monomer represented by the general formula (4) include ethylene, propylene, various butenes, various pentenes, various hexenes, various heptenes, various octenes, diisobutylene, triisobutylene, styrene, and various alkyl-substituted styrenes. .

  Moreover, as a polyvinyl ether concerning this invention, what has the following terminal structures is suitable.

［式中、Ｒ^１１、Ｒ^２１及びＲ^３１は互いに同一でも異なっていてもよく、それぞれ水素原子又は炭素数１〜８の炭化水素基を示し、Ｒ^４１は炭素数１〜１０の二価の炭化水素基又は炭素数２〜２０の二価のエーテル結合酸素含有炭化水素基を示し、Ｒ^５１は炭素数１〜２０の炭化水素基を示し、ｎはポリビニルエーテルについてのｎの平均値が０〜１０となるような数を示し、ｎが２以上の場合には、複数のＲ^４１Ｏは同一でも異なっていてもよい。］

［式中、Ｒ^６１、Ｒ^７１、Ｒ^８１及びＲ^９１は互いに同一でも異なっていてもよく、それぞれ水素原子又は炭素数１〜２０の炭化水素基を示す。］

［式中、Ｒ^１２，Ｒ^２２及びＲ^３２は互いに同一でも異なっていてもよく、それぞれ水素原子又は炭素数１〜８の炭化水素基を示し、Ｒ^４２は炭素数１〜１０の二価の炭化水素基又は炭素数２〜２０の二価のエーテル結合酸素含有炭化水素基を示し、Ｒ^５２は炭素数１〜２０の炭化水素基を示し、ｐはポリビニルエーテルについてのｐの平均値が０〜１０となるような数を示し、ｐが２以上の場合には、複数のＲ^４１Ｏは同一でも異なっていてもよい。］

［式中、Ｒ^６２、Ｒ^７２、Ｒ^８２及びＲ^９２は互いに同一でも異なっていてもよく、それぞれ水素原子又は炭素数１〜２０の炭化水素基を示す。］ (A) One having one end represented by the general formula (5) or (6) and the other end represented by the general formula (7) or (8).

[Wherein R ¹¹ , R ²¹ and R ³¹ may be the same as or different from each other, and each represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and R ⁴¹ is a divalent divalent having 1 to 10 carbon atoms. A hydrocarbon group or a divalent ether-bonded oxygen-containing hydrocarbon group having 2 to 20 carbon atoms, R ⁵¹ represents a hydrocarbon group having 1 to 20 carbon atoms, and n is an average value of n for polyvinyl ether of 0 In the case where n is 2 or more, the plurality of R ⁴¹ Os may be the same or different. ]

[Wherein, R ⁶¹ , R ⁷¹ , R ⁸¹ and R ⁹¹ may be the same as or different from each other, and each represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms. ]

[Wherein R ¹² , R ²² and R ³² may be the same or different from each other, each represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and R ⁴² is a divalent one having 1 to 10 carbon atoms. A hydrocarbon group or a divalent ether-bonded oxygen-containing hydrocarbon group having 2 to 20 carbon atoms, R ⁵² represents a hydrocarbon group having 1 to 20 carbon atoms, and p is an average value of p for polyvinyl ether of 0. In the case where p is 2 or more, the plurality of R ⁴¹ Os may be the same or different. ]

[Wherein, R ⁶² , R ⁷² , R ⁸² and R ⁹² may be the same as or different from each other, and each represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms. ]

［式中、Ｒ^１３、Ｒ^２３及びＲ^３３は同一でも異なっていてもよく、それぞれ水素原子又は炭素数１〜８の炭化水素基を示す。］ (B) One end is represented by the above general formula (5) or (6) and the other end is represented by the following general formula (9).

[Wherein, R ¹³ , R ²³ and R ³³ may be the same or different and each represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms. ]

Among such polyvinyl ether compounds, the following are particularly suitable as the main component of the lubricating oil for compression refrigerators of the present invention.
(1) One end is represented by the general formula (5) or (6), and the other end has a structure represented by the general formula (7) or (8), and R in the general formula (1) ¹ , R ² and R ³ are both hydrogen atoms, m is a number of 0 to 4, R ⁴ is a divalent hydrocarbon group having 2 to ⁴ carbon atoms, and R ⁵ is a hydrocarbon group having 1 to 20 carbon atoms. thing.
(2) A structure having only the structural unit represented by the general formula (1), wherein one terminal is represented by the general formula (5) and the other terminal is represented by the general formula (7). R ¹ , R ² and R ³ in the general formula (1) are all hydrogen atoms, m is a number of 0 to 4, R ⁴ is a divalent hydrocarbon group having 2 to ⁴ carbon atoms and R ⁵ is A hydrocarbon group having 1 to 20 carbon atoms.
(3) One end is represented by the general formula (5) or (6) and the other end is represented by the general formula (9), and R ¹ and R ² in the general formula (1) And R ³ is a hydrogen atom, m is a number of 0 to 4, R ⁴ is a divalent hydrocarbon group having 2 to ⁴ carbon atoms, and R ⁵ is a hydrocarbon group having 1 to 20 carbon atoms.
(4) It has only the structural unit represented by the general formula (1), one end of which is represented by the general formula (III), and the other end is represented by the general formula (9). R ¹ , R ² and R ³ in the general formula (1) are all hydrogen atoms, m is a number from 0 to 4, R ⁴ is a divalent hydrocarbon group having 2 to ⁴ carbon atoms, and R ^5. Is a divalent hydrocarbon group having 1 to 20 carbon atoms and R ⁵ is a hydrocarbon group having 1 to 20 carbon atoms.
(5) above (1) a respective ~ (4), ^{R 5} in the general formula (1) is a structural unit with said ^{R 5} is a hydrocarbon group having 1 to 3 carbon atoms having 3 to 20 carbon atoms Those having a structural unit which is a hydrocarbon group.

  The polyvinyl ether according to the present invention can be produced by radical polymerization, cationic polymerization, radiation polymerization of the above-described monomers. For example, a vinyl ether monomer can be polymerized using the method shown below to obtain a polymer having a desired viscosity. For the initiation of polymerization, a combination of Bronsted acids, Lewis acids or organometallic compounds with water, alcohols, phenols, acetals or vinyl ethers and adducts of carboxylic acids may be used. it can. Examples of Bronsted acids include hydrofluoric acid, hydrochloric acid, hydrobromic acid, hydroiodic acid, nitric acid, sulfuric acid, trichloroacetic acid, trifluoroacetic acid, and the like. Examples of Lewis acids include boron trifluoride, aluminum trichloride, aluminum tribromide, tin tetrachloride, zinc dichloride, and ferric chloride. Among these Lewis acids, boron trifluoride is particularly preferred. Is preferred. Examples of the organometallic compound include diethyl aluminum chloride, ethyl aluminum chloride, diethyl zinc and the like.

  Any adduct of water, alcohols, phenols, acetals or vinyl ethers and carboxylic acid combined with these can be selected. Here, examples of the alcohols include those having 1 to 20 carbon atoms such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, tert-butanol, various pentanols, various hexanols, various heptanols, and various octanols. Examples thereof include unsaturated aliphatic alcohols having 3 to 10 carbon atoms such as saturated aliphatic alcohols and allyl alcohols. Examples of the carboxylic acid when an adduct of vinyl ethers and carboxylic acid is used include acetic acid; propionic acid; n-butyric acid; isobutyric acid; n-valeric acid; isovaleric acid; 2-methylbutyric acid; pivalic acid; 2,2-dimethylbutyric acid; 2-methylvaleric acid; 3-methylvaleric acid; 4-methylvaleric acid; enanthic acid; 2-methylcaproic acid; caprylic acid; 2-ethylcaproic acid; -Propyl valeric acid; n-nonanoic acid; 3,5,5-trimethylcaproic acid; caprylic acid; undecanoic acid and the like.

  Further, the vinyl ethers may be the same as those used for the polymerization, or may be different. This adduct of vinyl ethers and the carboxylic acid is obtained by mixing and reacting them at a temperature of about 0 to 100 ° C., separated by distillation or the like, and can be used for the reaction, but separated as it is. It can also be used for the reaction without. The polymerization initiation terminal of the polymer is such that when water, alcohols or phenols are used, hydrogen is bonded, and when acetals are used, one alkoxy group is eliminated from hydrogen or the used acetals. When an adduct of vinyl ethers and carboxylic acid is used, the alkylcarbonyloxy group derived from the carboxylic acid moiety is eliminated from the adduct of vinyl ethers and carboxylic acid.

  On the other hand, when water, alcohols, phenols, or acetals are used, the terminal ends are acetals, olefins, or aldehydes. In the case of an adduct of vinyl ethers and carboxylic acid, it becomes a carboxylic acid ester of hemiacetal. The terminal of the polymer thus obtained can be converted into a desired group by a known method. Examples of the desired group include residues such as saturated hydrocarbons, ethers, alcohols, ketones, nitriles, and amides, with saturated hydrocarbon, ether, and alcohol residues being preferred.

  The polymerization of the vinyl ether-based monomer can be initiated at a temperature between -80 to 150 ° C., and is usually carried out at a temperature in the range of −80 to 50 ° C., depending on the type of raw material and initiator. The polymerization reaction is completed in about 10 seconds to 10 hours after the start of the reaction. Regarding the regulation of molecular weight in this polymerization reaction, a polymer having a low average molecular weight can be obtained by increasing the amount of water, alcohols, phenols, acetals, and adducts of vinyl ethers and carboxylic acids with respect to vinyl ether monomers. It is done. Furthermore, a polymer having a low average molecular weight can be obtained by increasing the amount of the Bronsted acids or Lewis acids. This polymerization reaction is usually performed in the presence of a solvent. The solvent is not particularly limited as long as it dissolves a necessary amount of the reaction raw material and is inert to the reaction. For example, hydrocarbons such as hexane, benzene, and toluene, and ethyl ether, 1,2- Ether solvents such as dimethoxyethane and tetrahydrofuran can be preferably used. This polymerization reaction can be stopped by adding an alkali. After completion of the polymerization reaction, a polyvinyl ether compound having the target structural unit represented by the general formula (1) can be obtained by subjecting to an ordinary separation / purification method as necessary.

  As described above, the polyvinyl ether according to the present invention needs to have a carbon / oxygen molar ratio in the range of 4.0 to 5.8, but by adjusting the carbon / oxygen molar ratio of the raw material monomer, A polymer having the molar ratio within the above range can be produced. That is, if the ratio of the monomer having a large carbon / oxygen molar ratio is large, a polymer having a large carbon / oxygen molar ratio is obtained, and if the ratio of the monomer having a small carbon / oxygen molar ratio is large, the polymer having a small carbon / oxygen molar ratio is obtained. Is obtained. In addition, as shown in the above polymerization method of vinyl ether monomers, it is also possible to use water, alcohols, phenols, acetals, adducts of vinyl ethers and carboxylic acids, and combinations of monomers used as initiators. It is. If alcohols or phenols having a larger carbon / oxygen molar ratio than the monomer to be polymerized are used as initiators, a polymer having a larger carbon / oxygen molar ratio than the raw material monomer can be obtained, while carbon / such as methanol or methoxyethanol If an alcohol having a small oxygen molar ratio is used, a polymer having a carbon / oxygen molar ratio smaller than that of the raw material monomer can be obtained.

  Furthermore, when a vinyl ether monomer and a hydrocarbon monomer having an olefinic double bond are copolymerized, a polymer having a carbon / oxygen molar ratio larger than the carbon / oxygen molar ratio of the vinyl ether monomer is obtained. Can be adjusted by the ratio of the hydrocarbon monomer having an olefinic double bond to be used and the number of carbon atoms.

The kinematic viscosity at 100 ° C. of the polyvinyl ether according to the present invention is preferably 5 to 20 mm ² / s, preferably 6 to 18 mm ² / s, more preferably 7 to 16 mm ² / s, and still more preferably 8 to 15 mm. ² / s, most preferably 10-15 mm ² / s. When the kinematic viscosity at 100 ° C. is less than the lower limit, the lubricity in the presence of the refrigerant becomes insufficient. On the other hand, when the upper limit is exceeded, the composition range showing compatibility with the refrigerant becomes narrow, and the refrigerant compression Machine lubrication and heat exchange in the evaporator are likely to be hindered. Moreover, kinematic viscosity at 40 ° C. of the polyvinyl ether is preferably a kinematic viscosity at 40 ° C. is 10 to 200 mm ² / s, more preferably 20 to 150 mm ² / s. If the kinematic viscosity at 40 ° C. is less than 10 mm ² / s, the lubricity and the sealing performance of the compressor tend to be reduced. If the kinematic viscosity exceeds 200 mm ² / s, it is compatible with the refrigerant under low temperature conditions. The composition range showing the above becomes narrow, and the lubrication failure of the refrigerant compressor and the heat exchange in the evaporator tend to be hindered.

  Further, the pour point of the polyvinyl ether represented by the general formula (1) is preferably −10 ° C. or less, and more preferably −20 to −50 ° C. If polyvinyl ether having a pour point of −10 ° C. or higher is used, the refrigerating machine oil tends to solidify in the refrigerant circulation system at low temperatures.

  Moreover, in the manufacturing process of the polyvinyl ether represented by the general formula (1), a side reaction may occur and an unsaturated group such as an allyl group may be formed in the molecule. When an unsaturated group is formed in the polyvinyl ether molecule, the thermal stability of the polyvinyl ether itself is reduced, a polymer is produced and sludge is produced, or the antioxidant property (antioxidant property) is lowered. Phenomena such as generation of oxides are likely to occur. In particular, when a peroxide is generated, it decomposes to generate a compound having a carbonyl group, and the compound having a carbonyl group generates sludge, which easily causes capillary clogging.

  Accordingly, the polyvinyl ether according to the present invention is preferably one having a low degree of unsaturation derived from an unsaturated group or the like, specifically preferably 0.04 meq / g or less, and 0.03 meq / g or less. More preferably, it is most preferably 0.02 meq / g or less. The peroxide value is preferably 10.0 meq / kg or less, more preferably 5.0 meq / kg or less, and most preferably 1.0 meq / kg. Furthermore, the carbonyl value is preferably 100 ppm by weight or less, more preferably 50 ppm by weight or less, and most preferably 20 ppm by weight or less.

  In addition, the degree of unsaturation, the peroxide value, and the carbonyl value according to the present invention are values measured by a standard oil analysis test method established by the Japan Oil Chemists' Society. That is, the degree of unsaturation according to the present invention refers to reacting a sample with a Wis solution (ICl-acetic acid solution), leaving it in the dark, and then reducing excess ICl to iodine, and converting the iodine content with sodium thiosulfate. The iodine value is calculated by titration, and the iodine value is converted into a vinyl equivalent (meq / g); the peroxide value according to the present invention refers to the free iodine produced by adding potassium iodide to a sample. Is a value (meq / kg) obtained by converting this free iodine into the number of milliequivalents per 1 kg of the sample; the carbonyl value according to the present invention refers to 2,4-dinitrophenylhydrazine added to the sample. The quinoid ion is colored, and the absorbance at 480 nm of this sample is measured. Based on the calibration curve obtained in advance using cinnamaldehyde as a standard substance, Say-converted value Le amount (wt ppm). The hydroxyl value is not particularly limited, but is desirably 10 mgKOH / g, preferably 5 mgKOH / g, and more preferably 3 mgKOH / g.

  The refrigerating machine oil of the present invention contains polyvinyl ether having the above-described configuration, and even when only the polyvinyl ether is used alone, low-temperature fluidity, lubricity and stability are sufficiently high, and Although it exhibits excellent properties such as having a sufficiently wide compatible region with the fluoropropene refrigerant, other base oils and additives described later may be added as necessary. The content of the polyvinyl ether in the refrigerating machine oil of the present invention is not particularly limited as long as the above excellent characteristics are not impaired, but is preferably 50% by mass or more based on the total amount of the refrigerating machine oil, and 70% by mass. % Or more, more preferably 80% by mass or more, and particularly preferably 90% by mass or more. If the content of the polyvinyl ether represented by the general formula (1) is less than 50% by mass, any of various performances such as lubricity, refrigerant compatibility, thermal / chemical stability, etc. of the refrigerating machine oil is unsatisfactory. It tends to be sufficient.

  In the refrigerating machine oil of the present invention, the content of the polyvinyl ether according to the present invention is not particularly limited, but the refrigerating machine oil is excellent in terms of various properties such as lubricity, refrigerant compatibility, thermal / chemical stability, and electrical insulation. It is preferable to contain 50% by mass or more based on the total amount, more preferably 70% by mass or more, still more preferably 80% by mass or more, and most preferably 90% by mass or more.

  The refrigerating machine oil of the present invention may consist only of the polyvinyl ether according to the present invention, but may further contain a base oil and various additives other than the polyvinyl ether. Moreover, the working fluid composition for a refrigerator of the present invention may further contain a base oil and various additives other than the polyvinyl ether according to the present invention. In the following description, the contents of the base oil and additives other than the polyvinyl ether according to the present invention are shown based on the total amount of the refrigerating machine oil, but the contents of these components in the refrigerating machine fluid composition are as follows: When the total amount of refrigerating machine oil is used as a reference, it is desirable to select so as to be within a preferable range described later.

  Base oils other than polyvinyl ether according to the present invention include mineral oils, olefin polymers, naphthalene compounds, hydrocarbon oils such as alkylbenzenes, and ester base oils (monoesters, diesters, polyol esters, etc.), polyalkylene glycols, Synthetic oils containing oxygen such as polyvinyl ethers, ketones, polyphenyl ethers, silicones, polysiloxanes, perfluoroethers other than the present invention may be used in combination. Among the above-mentioned synthetic oils containing oxygen, polyol esters and polyalkylene glycols are preferably used.

  Moreover, the refrigerating machine oil of the present invention can be used in a form in which various additives are further blended as necessary. In the following description, the additive content is shown based on the total amount of the refrigerating machine oil composition, but the content of these components in the refrigerating machine fluid composition is based on the total amount of the refrigerating machine oil composition. In this case, it is desirable to select so that it is within a preferable range described later.

  In order to further improve the wear resistance and load resistance of the refrigerating machine oil and working fluid composition for the refrigerating machine of the present invention, phosphoric acid ester, acidic phosphoric acid ester, thiophosphoric acid ester, amine salt of acidic phosphoric acid ester, chlorine At least one phosphorus compound selected from the group consisting of phosphorylated phosphates and phosphites can be blended. These phosphorus compounds are esters of phosphoric acid or phosphorous acid with alkanols and polyether type alcohols or derivatives thereof.

  Specifically, for example, as phosphate ester, tributyl phosphate, tripentyl phosphate, trihexyl phosphate, triheptyl phosphate, trioctyl phosphate, trinonyl phosphate, tridecyl phosphate, triundecyl phosphate, tridodecyl phosphate, tritridecyl Phosphate, tritetradecyl phosphate, tripentadecyl phosphate, trihexadecyl phosphate, triheptadecyl phosphate, trioctadecyl phosphate, trioleyl phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, xyl Examples include rhenyl diphenyl phosphate.

  Examples of acidic phosphate esters include monobutyl acid phosphate, monopentyl acid phosphate, monohexyl acid phosphate, monoheptyl acid phosphate, monooctyl acid phosphate, monononyl acid phosphate, monodecyl acid phosphate, monoundecyl acid phosphate, monododecyl Acid phosphate, monotridecyl acid phosphate, monotetradecyl acid phosphate, monopentadecyl acid phosphate, monohexadecyl acid phosphate, monoheptadecyl acid phosphate, monooctadecyl acid phosphate, monooleyl acid phosphate, dibutyl acid phosphate, dipentyl acid , Dihexyl reed Dophosphate, diheptyl acid phosphate, dioctyl acid phosphate, dinonyl acid phosphate, didecyl acid phosphate, diundecyl acid phosphate, didodecyl acid phosphate, ditridecyl acid phosphate, ditetradecyl acid phosphate, dipentadecyl acid, dipentadecyl acid Examples include hexadecyl acid phosphate, diheptadecyl acid phosphate, dioctadecyl acid phosphate, dioleyl acid phosphate, and the like.

  Examples of thiophosphates include tributyl phosphorothioate, tripentyl phosphorothionate, trihexyl phosphorothionate, triheptyl phosphorothionate, trioctyl phosphorothionate, trinonyl phosphorothionate, tridecyl phosphorothioate. Phorothionate, triundecyl phosphorothionate, tridodecyl phosphorothionate, tritridecyl phosphorothionate, tritetradecyl phosphorothionate, tripentadecyl phosphorothionate, trihexadecyl phosphorothionate, Triheptadecyl phosphorothioate, trioctadecyl phosphorothionate, trioleyl phosphorothionate, triphenyl phosphorothionate, tricresyl phosphorothionate, trixyl Cycloalkenyl phosphorothionate, cresyldiphenyl phosphorothionate, like carboxymethyl Les sulfonyl diphenyl phosphorothionate.

  Examples of the amine salt of acidic phosphate ester include methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, heptylamine, octylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, Examples thereof include salts with amines such as dipentylamine, dihexylamine, diheptylamine, dioctylamine, trimethylamine, triethylamine, tripropylamine, tributylamine, tripentylamine, trihexylamine, triheptylamine, trioctylamine.

  Examples of the chlorinated phosphate ester include tris-dichloropropyl phosphate, tris-chloroethyl phosphate, tris-chlorophenyl phosphate, polyoxyalkylene bis [di (chloroalkyl)] phosphate, and the like. As phosphites, dibutyl phosphite, dipentyl phosphite, dihexyl phosphite, diheptyl phosphite, dioctyl phosphite, dinonyl phosphite, didecyl phosphite, diundecyl phosphite, didodecyl phosphite, dioleyl Phosphite, diphenyl phosphite, dicresyl phosphite, tributyl phosphite, tripentyl phosphite, trihexyl phosphite, triheptyl phosphite, trioctyl phosphite, trinonyl phosphite, tridecyl phosphite, triundecyl phosphite Phyto, tridodecyl phosphite, trioleyl phosphite, triphenyl phosphite, tricresyl phosphite and the like can be mentioned. Mixtures of these can also be used.

  When the refrigerating machine oil and the working fluid composition for a refrigerating machine of the present invention contain the phosphorus compound, the content of the phosphorus compound is not particularly limited, but is based on the total amount of refrigerating machine oil (based on the total amount of base oil and all blended additives). It is preferable that it is 0.01-5.0 mass%, and it is more preferable that it is 0.02-3.0 mass%. In addition, the said phosphorus compound may be used individually by 1 type, and may use 2 or more types together.

  In addition, the refrigerating machine oil and the working fluid composition for the refrigerating machine of the present invention include a phenyl glycidyl ether type epoxy compound, an alkyl glycidyl ether type epoxy compound, and a glycidyl ester type epoxy compound in order to further improve the thermal and chemical stability. , An allyloxirane compound, an alkyloxirane compound, an alicyclic epoxy compound, an epoxidized fatty acid monoester, and an epoxidized vegetable oil can be contained.

  Specific examples of the phenyl glycidyl ether type epoxy compound include phenyl glycidyl ether and alkylphenyl glycidyl ether. As used herein, the alkylphenyl glycidyl ether includes those having 1 to 3 alkyl groups having 1 to 13 carbon atoms, and those having one alkyl group having 4 to 10 carbon atoms, such as n-butylphenyl glycidyl. Ether, i-butylphenyl glycidyl ether, sec-butylphenyl glycidyl ether, tert-butylphenyl glycidyl ether, pentylphenyl glycidyl ether, hexylphenyl glycidyl ether, heptylphenyl glycidyl ether, octylphenyl glycidyl ether, nonylphenyl glycidyl ether, decylphenyl A glycidyl ether etc. can be illustrated as a preferable thing.

  As the alkyl glycidyl ether type epoxy compound, specifically, decyl glycidyl ether, undecyl glycidyl ether, dodecyl glycidyl ether, tridecyl glycidyl ether, tetradecyl glycidyl ether, 2-ethylhexyl glycidyl ether, neopentyl glycol diglycidyl ether, Examples thereof include trimethylolpropane triglycidyl ether, pentaerythritol tetraglycidyl ether, 1,6-hexanediol diglycidyl ether, sorbitol polyglycidyl ether, polyalkylene glycol monoglycidyl ether, and polyalkylene glycol diglycidyl ether.

  Specific examples of the glycidyl ester type epoxy compound include phenyl glycidyl ester, alkyl glycidyl ester, alkenyl glycidyl ester, etc., and preferable ones are glycidyl-2,2-dimethyloctanoate, glycidyl benzoate, glycidyl acrylate. And glycidyl methacrylate.

  Specific examples of the allyloxirane compound include 1,2-epoxystyrene and alkyl-1,2-epoxystyrene.

  Specific examples of the alkyloxirane compound include 1,2-epoxybutane, 1,2-epoxypentane, 1,2-epoxyhexane, 1,2-epoxyheptane, 1,2-epoxyoctane, 1,2- Epoxy nonane, 1,2-epoxydecane, 1,2-epoxyundecane, 1,2-epoxydodecane, 1,2-epoxytridecane, 1,2-epoxytetradecane, 1,2-epoxypentadecane, 1,2- Examples include epoxyhexadecane, 1,2-epoxyheptadecane, 1,1,2-epoxyoctadecane, 2-epoxynonadecane, 1,2-epoxyicosane and the like.

  Specific examples of the alicyclic epoxy compound include 1,2-epoxycyclohexane, 1,2-epoxycyclopentane, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, and bis (3,4 -Epoxycyclohexylmethyl) adipate, exo-2,3-epoxynorbornane, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate, 2- (7-oxabicyclo [4.1.0] hept-3- Yl) -spiro (1,3-dioxane-5,3 ′-[7] oxabicyclo [4.1.0] heptane, 4- (1′-methylepoxyethyl) -1,2-epoxy-2-methyl Examples include cyclohexane and 4-epoxyethyl-1,2-epoxycyclohexane.

  Specific examples of the epoxidized fatty acid monoester include an ester of an epoxidized fatty acid having 12 to 20 carbon atoms with an alcohol or phenol having 1 to 8 carbon atoms or an alkylphenol. In particular, butyl, hexyl, benzyl, cyclohexyl, methoxyethyl, octyl, phenyl and butylphenyl esters of epoxy stearate are preferably used.

  Specific examples of the epoxidized vegetable oil include epoxy compounds of vegetable oils such as soybean oil, linseed oil and cottonseed oil.

  Among these epoxy compounds, phenyl glycidyl ether type epoxy compounds, glycidyl ester type epoxy compounds, alicyclic epoxy compounds and epoxidized fatty acid monoesters are preferred. Of these, phenyl glycidyl ether type epoxy compounds and glycidyl ester type epoxy compounds are more preferred, and phenyl glycidyl ether, butylphenyl glycidyl ether, alkyl glycidyl esters or mixtures thereof are particularly preferred.

  When the refrigerating machine oil and the working fluid composition for a refrigerating machine of the present invention contain the above epoxy compound, the content of the epoxy compound is not particularly limited, but is 0.1 to 5.0% by mass based on the total amount of the refrigerating machine oil. It is preferably 0.2 to 2.0% by mass. In addition, the said epoxy compound may be used individually by 1 type, and may use 2 or more types together.

  In addition, the refrigerating machine oil and the working fluid composition for the refrigerating machine of the present invention can contain conventionally known additives for refrigerating machine oil as necessary in order to further enhance the performance. Examples of such additives include phenolic antioxidants such as di-tert-butyl-p-cresol and bisphenol A, phenyl-α-naphthylamine, N, N-di (2-naphthyl) -p-phenylenediamine, and the like. Amine-based antioxidants, anti-wear agents such as zinc dithiophosphate, extreme pressure agents such as chlorinated paraffin and sulfur compounds, oil-based agents such as fatty acids, antifoaming agents such as silicones, metal inertness such as benzotriazole Agents, viscosity index improvers, pour point depressants, detergent dispersants and the like. These additives may be used individually by 1 type, and may be used in combination of 2 or more type. The content of these additives is not particularly limited, but is preferably 10% by mass or less, more preferably 5% by mass or less, based on the total amount of refrigerating machine oil.

The kinematic viscosity of the refrigerating machine oil of the present invention is not particularly limited, but the kinematic viscosity at 40 ° C. is preferably 3 to 1000 mm ² / s, more preferably 4 to 500 mm ² / s, and most preferably 5 to 400 mm ² / s. can do. The kinematic viscosity at 100 ° C. is preferably 1 to 100 mm ² / s, more preferably ² to 50 mm ² / s.

  Further, the water content of the refrigerating machine oil of the present invention is not particularly limited, but can be preferably 500 ppm or less, more preferably 300 ppm or less, and most preferably 200 ppm or less based on the total amount of refrigerating machine oil. In particular, when it is used for a hermetic type refrigerator, the moisture content is required to be small from the viewpoint of the influence on the thermal / chemical stability and electrical insulation of the refrigerator oil.

  Further, the acid value of the refrigerating machine oil of the present invention is not particularly limited, but to prevent corrosion of the metal used in the refrigerating machine or piping, and to prevent the decomposition of the ester contained in the refrigerating machine oil of the present invention. Therefore, it can be preferably 0.1 mgKOH / g or less, more preferably 0.05 mgKOH / g or less. In addition, in this invention, an acid value means the acid value measured based on JISK2501 "Petroleum products and lubricating oil-neutralization value test method".

  Further, the ash content of the refrigerating machine oil of the present invention is not particularly limited, but is preferably 100 ppm or less, more preferably 50 ppm or less in order to increase the thermal and chemical stability of the refrigerating machine oil of the present invention and suppress the generation of sludge and the like. be able to. In the present invention, the ash means the value of ash measured in accordance with JIS K2272 “Testing method for ash and sulfated ash of crude oil and petroleum products”.

  The refrigerating machine oil of the present invention is used together with a fluoropropene refrigerant, and the working fluid composition for a refrigerating machine of the present invention contains a fluoropropene refrigerant.

  As the fluoropropene refrigerant, fluoropropene having 3 to 5 fluorine atoms is preferable. 1,2,3,3,3-pentafluoropropene (HFC-1225ye), 1,3,3,3-tetrafluoropropene (HFC) -1234ze), 2,3,3,3-tetrafluoropropene (HFC-1234yf), 1,2,3,3-tetrafluoropropene (HFC1234ye), and 3,3,3-trifluoropropene (HFC-1243zf) 1) or a mixture of two or more of them. From the viewpoint of the physical properties of the refrigerant, it is preferably one or more selected from HFC-1225ye, HFC-1234ze, and HFC-1234yf.

  The refrigerant used in the present invention may be a mixed refrigerant of a fluoropropene refrigerant and another refrigerant. Examples of other refrigerants include HFC refrigerants, fluorine-containing ether refrigerants such as bar fluoroethers, and natural refrigerants such as dimethyl ether, ammonia, and hydrocarbons.

  Examples of the HFC refrigerant include hydrofluorocarbons having 1 to 3 carbon atoms, preferably 1 to 2 carbon atoms. Specifically, for example, difluoromethane (HFC-32), trifluoromethane (HFC-23), pentafluoroethane (HFC-125), 1,1,2,2-tetrafluoroethane (HFC-134), 1, 1,1,2-tetrafluoroethane (HFC-134a), 1,1,1-trifluoroethane (HFC-143a), 1,1-difluoroethane (HFC-152a), fluoroethane (HFC-161), 1 1,1,2,3,3,3-heptafluoropropane (HFC-227ea), 1,1,1,2,3,3-hexafluoropropane (HFC-236ea), 1,1,1,3 , 3,3-hexafluoropropane (HFC-236fa), 1,1,1,3,3-pentafluoropropane (HFC-245fa), and 1,1, , 3,3-pentafluorobutane (HFC-365mfc), or a mixture of two or more thereof. These refrigerants are appropriately selected depending on the application and required performance. For example, HFC-32 alone; HFC-23 alone; HFC-134a alone; HFC-125 alone; HFC-134a / HFC-32 = 60 to 80 mass % / 40-20 mass% mixture; HFC-32 / HFC-125 = 40-70 mass% / 60-30 mass% mixture; HFC-125 / HFC-143a = 40-60 mass% / 60-40 mass % Mixture; HFC-134a / HFC-32 / HFC-125 = 60 wt% / 30 wt% / 10 wt% mixture; HFC-134a / HFC-32 / HFC-125 = 40-70 wt% / 15- 35 mass% / 5 to 40 mass% mixture; HFC-125 / HFC-134a / HFC-143a = 35-55 mass% / 1-15 mass% / 40-60 mass Such as a mixture of preferred examples include. More specifically, a mixture of HFC-134a / HFC-32 = 70/30 mass%; a mixture of HFC-32 / HFC-125 = 60/40 mass%; HFC-32 / HFC-125 = 50/50 mass % Mixture (R410A); HFC-32 / HFC-125 = 45/55 wt% mixture (R410B); HFC-125 / HFC-143a = 50/50 wt% mixture (R507C); HFC-32 / HFC -125 / HFC-134a = 30/10/60 wt% mixture; HFC-32 / HFC-125 / HFC-134a = 23/25/52 wt% mixture (R407C); HFC-32 / HFC-125 / HFC-134a = 25/15/60 mass% mixture (R407E); HFC-125 / HFC-134a / HFC-143a = Mixtures of 4/4/52 wt% (R404A), and the like.

  Of the HFC refrigerants, saturated hydrofluorocarbons include difluoromethane (HFC-32), pentafluoroethane (HFC-125), 1,1,2,2-tetrafluoroethane (HFC-134), 1,1. , 1,2-Tetrafluoroethane (HFC-134a), 1,1-difluoroethane (HFC-152a), fluoroethane (HFC-161), 1,1,1,2,3,3,3-heptafluoropropane (HFC-227ea), 1,1,1,2,3,3-hexafluoropropane (HFC-236ea), 1,1,1,3,3,3-hexafluoropropane (HFC-236fa), 1, 1,1,3,3-pentafluoropropane (HFC-245fa), 1,1,1,3,3-pentafluorobutane (HFC-365 fc) is preferably one kind or a mixture of two or more kinds, and from the viewpoint of refrigerant physical properties, HFC-32, HFC-125, HFC-134a, HFC-152a, or HFC-32 and HFC- A mixture of 134a is preferred.

  The hydrocarbon refrigerant is preferably a hydrocarbon having 3 to 5 carbon atoms, specifically, for example, methane, ethylene, ethane, propylene, propane, cyclopropane, normal butane, isobutane, cyclobutane, methylcyclopropane, 2-methylbutane. , Normal pentane, or a mixture of two or more thereof. Among these, gas at 25 ° C. and 1 atm is preferably used, and propane, normal butane, isobutane, 2-methylbutane or a mixture thereof is preferable.

  Specific examples of the fluorine-containing ether refrigerant include HFE-134p, HFE-245mc, HFE-236mf, HFE-236me, HFE-338mcf, HFE-365mcf, HFE-245mf, HFE-347mmy, HFE-347mcc, HFE-125, HFE-143m, HFE-134m, HFE-227me, etc. are mentioned, These refrigerant | coolants are suitably selected according to a use or required performance.

  When the refrigerant used in the present invention is a mixed refrigerant, the mixed refrigerant is at least one selected from fluoropropene refrigerant (hereinafter referred to as “refrigerant (A)”), saturated hydrofluorocarbon, 3 to 3 carbon atoms. 5 hydrocarbons, dimethyl ether, carbon dioxide, bis (trifluoromethyl) sulfide and at least one selected from trifluoroiodomethane refrigerant (hereinafter referred to as “refrigerant (B)”). .

  Further, when the refrigerant used in the present invention is a mixed refrigerant containing the refrigerant (A) and the refrigerant (B), the mixed refrigerant is preferably an azeotropic mixture, but has physical properties necessary as a refrigerant. If it does, it does not need to be an azeotrope in particular, The mixing ratio of both is preferably 1:99 to 99: 1, more preferably 5:95 to 95: 5.

  Furthermore, when the refrigerant used in the present invention is a mixed refrigerant containing the refrigerant (A) and the refrigerant (B), the mixed refrigerant is an HFC refrigerant other than a fluoropropene refrigerant or a saturated hydrofluorocarbon, or a bar fluoroether. And other natural refrigerants such as ammonia or hydrocarbons other than hydrocarbons having 3 to 5 carbon atoms.

  The refrigerating machine oil of the present invention is usually present in the form of a fluid composition for a refrigerating machine mixed with a fluoropropene refrigerant or a mixed refrigerant as described above in a refrigerating and air-conditioning apparatus. The mixing ratio of the refrigerating machine oil and the refrigerant in the composition and the mixing ratio of the refrigerating machine oil and the refrigerant in the working fluid composition for a refrigerating machine of the present invention are not particularly limited, but the refrigerating machine oil is preferable with respect to 100 parts by mass of the refrigerant. Is 1 to 500 parts by mass, more preferably 2 to 400 parts by mass.

  The refrigerating machine oil and the working fluid composition for a refrigerating machine of the present invention are preferably used for an air conditioner, a refrigerator, or an open or sealed car air conditioner having a reciprocating or rotating hermetic compressor. Further, the refrigerating machine oil and the working fluid composition for the refrigerating machine of the present invention are preferably used for a dehumidifier, a water heater, a freezer, a freezer / refrigerated warehouse, a vending machine, a showcase, a cooling device for a chemical plant, and the like. Furthermore, the refrigerating machine oil and the working fluid composition for a refrigerating machine of the present invention are also preferably used for those having a centrifugal compressor.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example at all.

[Examples 1-2, Comparative Examples 1-4]
In Examples 1-2 and Comparative Examples 1-4, refrigeration oil was prepared using base oils 1-6 shown below. Various properties of the obtained refrigerating machine oil are shown in Table 1.

(Base oil)
Base oil 1: copolymer of ethyl vinyl ether and isobutyl vinyl ether (ethyl vinyl ether / isobutyl vinyl ether = 7/1 (molar ratio), weight average molecular weight: 910, carbon / oxygen molar ratio: 4.25)
Base oil 2: Copolymer of ethyl vinyl ether and isobutyl vinyl ether (ethyl vinyl ether / isobutyl vinyl ether = 2/1 (molar ratio), weight average molecular weight: 740, carbon / oxygen molar ratio: 4.67)
Base oil 3: polyisobutyl vinyl ether. (Weight average molecular weight: 1000, carbon / oxygen molar ratio: 6.00)
Base oil 4: polyethylene propylene glycol dimethyl ether. (Mole ratio of ethylene group / propylene group: 50/50, weight average molecular weight: 1100)
Base oil 5: Ester base oil of n-heptanoic acid and pentaerythritol 6: Naphthenic mineral oil.

  Next, the evaluation test shown below was implemented about each refrigeration oil of Examples 1-2 and Comparative Examples 1-4.

(Evaluation of refrigerant compatibility)
In accordance with JIS-K-2211 “Refrigerating machine oil” “Compatibility testing method with refrigerant”, 2 g of refrigerating machine oil is blended with 18 g of 2,3,3,3-tetrafluoropropene, and the refrigerant and refrigerating machine oil are mixed. Were observed to be mutually dissolved at 0 ° C. The obtained results are shown in Table 1. In Table 1, “compatible” means that the refrigerant and the refrigerating machine oil are mutually dissolved, and “separation” means that the refrigerant and the refrigerating machine oil are separated into two layers.

(Evaluation of thermal and chemical stability)
In accordance with JIS-K-2211, 1 g of refrigerating machine oil (initial hue L0.5) whose water content was adjusted to 100 ppm or less, 1 g of 2,3,3,3-tetrafluoropropene, and catalyst (iron, copper, aluminum) Each wire) was sealed in a glass tube, heated to 150 ° C. and held for 1 week for testing. After the test, the hue of the refrigerator oil composition and the color change of the catalyst were evaluated. Hue was evaluated according to ASTM D156. Further, the color change of the catalyst was visually observed for the appearance, and it was evaluated whether it corresponded to no change, no gloss, or blackening. The obtained results are shown in Table 1.

Claims (4)

Polyvinyl ether having a structural unit represented by the following general formula (1) and having a carbon / oxygen molar ratio of 4.0 to 5.8, 1,3,3,3-tetrafluoropropene and 2,3 , 3,3-tetrafluoropropene, and at least one fluoropropene refrigerant.

[Wherein R ¹ , R ² and R ³ may be the same or different and each represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms; R ⁴ is a divalent carbon atom having 1 to 10 carbon atoms; A hydrogen group or a divalent ether-bonded oxygen-containing hydrocarbon group having 2 to 20 carbon atoms, R ⁵ represents a hydrocarbon group having 1 to 20 carbon atoms, and m is an average value of m for the polyvinyl ether of 0. And R ^{1 to} R ⁵ may be the same or different for each structural unit. When m is 2 or more in one structural unit, a plurality of R ⁴ O may be the same or different. ] Saturated hydrofluorocarbon, a hydrocarbon having 3 to 5 carbon atoms, dimethyl ether, carbon dioxide, characterized by further containing at least one selected from bis (trifluoromethyl) sulfide and trifluoroiodomethane refrigerants, The working fluid composition for a refrigerator according to claim 1 . Before SL saturated hydrofluorocarbon difluoromethane, pentafluoroethane, 1,1,2,2-tetrafluoroethane, 1,1,1,2-tetrafluoroethane, 1,1-difluoroethane, fluoroethane, 1,1 1,1,2,3,3,3-heptafluoropropane, 1,1,1,2,3,3-hexafluoropropane, 1,1,1,3,3,3-hexafluoropropane, 1,1 , 1,3,3-pentafluoropropane and 1,1,1,3,3-pentafluorobutane, and the hydrocarbon having 3 to 5 carbon atoms is propane, normal butane, isobutane The working fluid composition for a refrigerator according to claim 2 , wherein the working fluid composition is at least one selected from 2-methylbutane and normal pentane. Containing a polyvinyl ether having a structural unit represented by the following general formula (1) and having a carbon / oxygen molar ratio of 4.0 to 5.8 , 1,3,3,3-tetrafluoropropene and 2, A refrigerating machine oil which is used together with at least one fluoropropene refrigerant selected from 3,3,3-tetrafluoropropene .

[Wherein R ¹ , R ² and R ³ may be the same or different and each represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms; R ⁴ is a divalent carbon atom having 1 to 10 carbon atoms; A hydrogen group or a divalent ether-bonded oxygen-containing hydrocarbon group having 2 to 20 carbon atoms, R ⁵ represents a hydrocarbon group having 1 to 20 carbon atoms, and m is an average value of m for the polyvinyl ether of 0. And R ^{1 to} R ⁵ may be the same or different for each structural unit. When m is 2 or more in one structural unit, a plurality of R ⁴ O may be the same or different. ]