KR20180101383A - Composition for refrigerator oil and refrigerator - Google Patents

Abstract

A refrigerator oil according to an embodiment of the present invention includes a base oil containing an oxygen-containing organic compound, a polyphosphoric acid ester compound, and a benzotriazole-based compound.

Description

Composition for refrigerator oil and refrigerator

The present invention relates to a refrigerator oil and a composition for a refrigerator using the refrigerator oil.

In a refrigerator, a mixture of refrigerant and refrigerator oil (hereinafter, also referred to as " refrigerator composition ") is circulated in a closed system, and refrigerator oil is required to have compatibility with refrigerant, stability and lubrication performance. In order to satisfy these requirements, refrigerating machine oil containing an oxygen-containing organic compound such as a vinyl ether compound as a main component is widely used (see, for example, Patent Document 1).

On the other hand, in recent years, hydrofluorocarbons (HFC) have been used as refrigerants instead of hydrochlorofluorocarbons (HCFC) having a high environmental load. Among the HFCs, saturated hydrofluorocarbons (saturated HFCs) such as R32 (difluoroethane) and R410A (a mixture of difluoroethane and pentafluoroethane) are widely used.

As a technique for improving the lubrication performance such as compatibility with the saturated HFC refrigerant, abrasion resistance, and insolubility, there has been proposed a method of adding a phosphoric acid having one phosphorus atom such as tricresyl phosphate (TCP) (For example, see Patent Document 2).

It is also known that phosphate ester compounds having one phosphorus atom such as tricresyl phosphate (TCP) are used together with a benzotriazole-based compound in a lubricating oil composition to improve abrasion resistance (see Patent Documents 3 and 4).

Japanese Patent Application Laid-Open No. 6-128578 Japanese Patent Application Laid-Open No. 10-130683 Japanese Patent Application Laid-Open No. 8-259980 Japanese Patent Laid-Open No. 7-126680

However, in recent years, various refrigerating machines are required to save energy, and it is required to improve the coefficient of performance (COP). Therefore, the refrigeration oil is required to further reduce the friction coefficient at the sliding portion of the refrigerator in order to improve the COP in addition to the wear resistance.

However, as shown in Patent Documents 2 to 4, even when a benzotriazole-based compound is blended in addition to a phosphoric acid ester compound having one phosphorus atom such as TCP or TCP or the like, the lubricating oil composition, It is difficult to make the friction coefficient sufficiently low while improving the wear resistance.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to reduce the coefficient of friction while improving abrasion resistance when a refrigerator oil containing an oxygen-containing organic compound as base oil is used.

As a result of extensive studies, the inventors of the present invention have found that, by containing both a specific phosphorus compound having at least two phosphorus atoms in one molecule and a benzotriazole-based compound in a base oil containing an oxygen-containing organic compound, The present invention has been accomplished. The present invention provides the following refrigerator oil, refrigerator composition, and method for producing refrigerator oil.

(1) A refrigerator oil comprising a base oil containing an oxygen-containing organic compound, a polyphosphoric acid ester compound, and a benzotriazole-based compound.

(2) a refrigerant; and (c) a refrigerator oil described in (1) above.

(3) A method for producing refrigerator oil wherein at least a polyphosphoric ester compound and a benzotriazole-based compound are compounded in a base oil containing an oxygen-containing organic compound to obtain a refrigerator oil.

According to the present invention, there is provided a refrigerator oil capable of reducing the coefficient of friction while improving wear resistance by containing a phosphorus compound and a benzotriazole-based compound specific to the base oil.

Hereinafter, the present invention will be described with reference to embodiments.

A refrigerator oil according to one embodiment of the present invention includes a base oil, a polyphosphoric acid ester compound, and a benzotriazole compound. Hereinafter, each component contained in refrigerator oil will be described in detail.

[Base oil]

The base oil in the present embodiment includes an oxygen-containing organic compound. Examples of the oxygen-containing organic compound include synthetic oils containing ether groups, ketone groups, ester groups, carbonate groups and the like, as well as heteroatoms (sulfur atoms, fluorine atoms, chlorine atoms, silicon atoms and nitrogen atoms) . More specifically, a copolymer of polyvinylether (PVE), polyoxyalkylene glycol (PAG), poly (oxy) alkylene glycol or monoether and polyvinyl ether thereof (ECP), and And polyol esters (POE). The oxygen-containing organic compound may be used alone, or two or more thereof may be used in combination.

Among them, at least one selected from polyvinylether (PVE) and polyoxyalkylene glycols (PAG) is preferable, and among them, at least one selected from polyvinyl ethers (PVE) desirable. On the other hand, PVE is particularly preferably used for a polyphosphoric acid ester compound represented by the following formula (1) and R ⁹ is a group represented by the formula (2) or a polyphosphoric acid ester compound represented by the formula (5) It is easy to improve the coefficient of friction and wear resistance.

The oxygen-containing organic compound is a main component of the refrigerating machine oil. The oxygen-containing organic compound is preferably contained in an amount of 70 to 99.98 mass%, more preferably 90 to 99.5 mass%, and more preferably 93.0 to 99.5 mass% More preferably 99.3% by mass.

Hereinafter, PVE, PAG, ECP, and POE used as a base oil will be described in more detail.

<Polyvinyl Ether (PVE)>

The polyvinyl ether (PVE) is a polymer having a constituent unit derived from a vinyl ether, and specifically includes a polyvinyl compound having a constitutional unit represented by the following formula (A-1).

R ^1a , R ^2a and R ^3a in the above formula (A-1) each independently represent a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and they may be the same or different. Specific examples of the hydrocarbon group include hydrocarbon groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, A heptyl group, and various octyl groups; Cycloalkyl groups such as cyclopentyl group, cyclohexyl group, various methylcyclohexyl groups, various ethylcyclohexyl groups and various dimethylcyclohexyl groups; An aryl group such as a phenyl group, various methylphenyl groups, various ethylphenyl groups, various dimethylphenyl groups and the like; Benzyl group, various phenylethyl groups, and various methylbenzyl groups, but alkyl groups are preferred.

R ^1a , R ^2a and R ^3a are each preferably a hydrogen atom or an alkyl group having 3 or less carbon atoms, more preferably a hydrogen atom. On the other hand, r in the formula (A-1) represents the number of repeating units and the average value thereof is a number in the range of 0 to 10, preferably 0.

R ^4a represents a divalent hydrocarbon group having 2 to 10 carbon atoms, and specific examples of the divalent hydrocarbon group having 2 to 10 carbon atoms include an ethylene group, a phenylethylene group, a 1,2-propylene group, a 2-phenyl- A divalent aliphatic hydrocarbon group such as a 1,2-propylene group, a 1,3-propylene group, various butylene groups, various pentylene groups, various hexylene groups, various heptylene groups, various octylene groups, various nonylene groups, ; Alicyclic hydrocarbon groups having two bonding sites in alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, ethylcyclohexane, dimethylcyclohexane and propylcyclohexane; Divalent aromatic hydrocarbon groups such as various phenylene groups, various methylphenylene groups, various ethylphenylene groups, various dimethylphenylene groups and various naphthylene groups; Alkylaromatic hydrocarbon groups each having a monovalent bonding site at an alkyl moiety and an aromatic moiety of an alkylaromatic hydrocarbon such as toluene or ethylbenzene; And alkylaromatic hydrocarbon groups having a bonding site at the alkyl group portion of a polyalkylaromatic hydrocarbon such as xylene and diethylbenzene. Of these, aliphatic hydrocarbon groups having 2 to 4 carbon atoms are more preferred. The plurality of R ^4a O may be the same or different.

R ^5a in the formula (A-1) represents a hydrocarbon group having 1 to 10 carbon atoms, and specifically, the hydrocarbon group includes a methyl group, ethyl group, n-propyl group, isopropyl group, n- An alkyl group such as a butyl group, a sec-butyl group, a tert-butyl group, various pentyl groups, various hexyl groups, various heptyl groups, various octyl groups, various nonyl groups and various decyl groups; Cycloalkyl groups such as cyclopentyl group, cyclohexyl group, various methylcyclohexyl groups, various ethylcyclohexyl groups, various propylcyclohexyl groups, and various dimethylcyclohexyl groups; Aryl groups such as a phenyl group, various methylphenyl groups, various ethylphenyl groups, various dimethylphenyl groups, various propylphenyl groups, various trimethylphenyl groups, various butylphenyl groups, and various naphthyl groups; An arylalkyl group such as a benzyl group, various phenylethyl groups, various methylbenzyl groups, various phenylpropyl groups, and various phenylbutyl groups. Of these, a hydrocarbon group having 1 to 8 carbon atoms is preferable, and an alkyl group having 1 to 6 carbon atoms is more preferable. On the other hand, the alkyl group may be any of linear, branched and cyclic.

Among the polyvinyl compounds having the structural unit represented by the above formula (A-1), the constituent units in which all of R ^1a , R ^2a and R ^3a are hydrogen atoms, r is 0, and R ^5a is an ethyl group, %, And R &lt; ^5a &gt; is an alkyl group having 3 or 4 carbon atoms. The proportion of the constituent unit in which R ^5a is an ethyl group is 70 to 100 mol%, the proportion of the constituent unit in which R ^5a is an alkyl group having 3 or 4 carbon atoms is more preferably 0 to 30 mol% 95%, and the latter is more preferably 5 to 20 mol%.

As the alkyl group having 3 or 4 carbon atoms for R ^5a , an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group and a tert-butyl group can be used, Do.

The polyvinyl ether compound has a structural unit represented by the above formula (A-1), and the number of repeating units may be appropriately selected according to the desired kinematic viscosity. The polyvinyl ether-based compound can be produced by polymerization of the corresponding vinyl ether-based monomer. The vinyl ether monomer which can be used herein is represented by the following formula (A-2).

(Wherein R ^1a , R ^2a , R ^3a , R ^4a and R ^5a and r are the same as above)

Examples of the vinyl ether monomer include vinylmethyl ether, vinylethyl ether, vinyl-n-propyl ether, vinyl-isopropyl ether, vinyl-n-butyl N-hexyl ether, vinyl-2-methoxyethyl ether, vinyl-2-ethoxyethyl ether, vinyl-isobutyl ether, vinyl-sec-butyl ether, vinyl-tert-butyl ether, vinyl- Vinyl-2-methoxypropyl ether, vinyl-3,6-dioxaheptyl ether, vinyl-3,6,9-trioxadecyl ether, Vinyl-1,4-dimethyl-3,6-dioxaheptyl ether, vinyl-1,4,7-trimethyl-3,6,9-trioxadecyl ether, vinyl- Decyl ether, 1-methoxypropene, 1-ethoxypropene, 1-n-propoxypropene, 1-isopropoxypropane, , 1-n-butoxypropene, 1-isobutoxypropene, 1-sec-butoxypropene, 1-tert-butoxypropene, 2-methoxypropene, Isopropoxypropane, 2-n-propoxypropene, 2-isopropoxypropene, 2-n-butoxypropene, Butene, 1-n-butoxy-1-butene, 1-n-butoxy-1-butene, Butene, 1-tert-butoxy-1-butene, 2-methoxy-1-butene, 2-ethoxy- Butene, 2-isopropoxy-1-butene, 2-isopropoxy-1-butene, Butene, 2-n-butoxy-1-butene, 2-n-propoxy-2-butene, 2-isopropoxy 2-butoxy-2-butene, 2-sec-butoxy-2-butene and 2-tert- . These vinyl ether-based monomers can be produced by a known method.

A monovalent group derived from a saturated hydrocarbon, ether, alcohol, ketone, amide, nitrile or the like may be introduced into the terminal portion of the polymer represented by the formula (A-1) by a known method.

Among them, the polyvinyl ether compound preferably has the following terminal structures (1) to (4).

(1) a compound wherein one end thereof is represented by the following formula (A-1-i) and the other end is represented by the following formula (A-1-ii)

(Wherein R ^6a , R ^7a and R ^8a each independently represent a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and they may be the same or different) R ^9a represents a divalent hydrocarbon group having 2 to 10 carbon atoms, R ^10a represents a number of from 1 to 10 hydrocarbon group of a carbon number, r1 is the average value is 0 to 10, if R ^9a O a plurality, the plurality of R ^9a is O may be the same or different.)

(Wherein R ^11a , R ^12a and R ^13a each independently represents a hydrogen atom or a hydrocarbon group of 1 to 8 carbon atoms, and they may be the same or different, and R ^14a represents a divalent hydrocarbon group of 2 to 10 carbon atoms, R ^15a is a group having a carbon number of 1 to 10 hydrocarbon group, r2 denotes the number of the average value is 0 to 10, if there is a plurality, the plurality of R ^14a O O R ^14a are may be the same or different.)

(A-1-i-1), and the other end thereof is represented by the formula (A-1-iii)

(Wherein, R ^16a, R ^17a and R ^18a each independently represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, they may be the same or different from each other. R ^19a and R ^21a are each independently a carbon number of 2 to 10 R ^20a and R ^22a each independently represent a hydrocarbon group of 1 to 10 carbon atoms, they may be the same or different, and r 3 and r 4 are each an average value of 0 represents a number of from to 10, and they may be the same or different from each other, and a plurality of R ^19a when R ^19a O with a plurality of O are be the same or different, a plurality of R ^21a when a plurality of R ^21a O O may be the same or different.)

(3) one end of which is represented by the above formula (A-1-i) and the other end has an olefinic unsaturated bond

(A-1-i), and the other end is represented by the formula (A-1-iv)

(Wherein R ^23a , R ^24a and R ^25a each represent a hydrogen atom or a hydrocarbon group of 1 to 8 carbon atoms, and they may be the same or different)

The polyvinyl ether-based mixture may be a mixture of two or more kinds selected from those having the terminal structures (1) to (4). As such a mixture, for example, a mixture of (1) and (4), and a mixture of (2) and (3) are preferably used.

The degree of polymerization, the terminal structure, and the like are preferably selected so that the viscosity of the base oil of the polyvinyl ether compound is within the range of the base oil described below. The polyvinyl ether compound may be used singly or in combination of two or more kinds.

Among the polyvinyl compounds having the structural unit represented by the above formula (A-1), one terminal is represented by the above formula (A-1-i) and the other terminal is represented by the above formula (A-1-ii ).

Among these, in the formula (A-1-i) and the formula (A-1-ii), R 6a, R 7a, R 8a, R 11a, R 12a and R ^13a together as a hydrogen atom, r1 and r2 Is 0, and R ^10a and R ^15a are more preferably an alkyl group having 1 to 4 carbon atoms.

&Lt; Polyoxyalkylene glycols (PAG) &gt;

Examples of the polyoxyalkylene glycols (PAG) include compounds represented by the following formula (B-1). On the other hand, when PAG is contained in the base oil, the PAG may be used alone or in combination of two or more.

R ^1b - [(OR ^2b ) _m -OR ^3b ] _n (B-1)

(Wherein R ^1b represents a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, an acyl group having 2 to 10 carbon atoms, a hydrocarbon group having 2 to 6 carbon atoms or a hydrocarbon group having 1 to 10 carbon atoms Containing hydrocarbon group, R ^2b is an alkylene group having 2 to 4 carbon atoms, R ^3b is a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, an acyl group having 2 to 10 carbon atoms, or an oxygen- And m represents the number of m.times.n average values from 6 to 80.)

In the above formula (B-1), each of the monovalent hydrocarbon groups of 1 to 10 carbon atoms in R ^1b and R ^3b may be any of linear, branched and cyclic. The hydrocarbon group is preferably an alkyl group. Specific examples thereof include methyl, ethyl, n-propyl, isopropyl, various butyl, various pentyl, A decyl group, a cyclopentyl group, and a cyclohexyl group. When the number of carbon atoms in the monovalent hydrocarbon group is 10 or less, compatibility with the refrigerant is improved. From such a viewpoint, the carbon number of the monovalent hydrocarbon group is more preferably 1 to 4.

The hydrocarbon group moiety of the acyl group having 2 to 10 carbon atoms in each of R ^1b and R ^3b may be linear, branched or cyclic. The hydrocarbon group portion of the acyl group is preferably an alkyl group, and specific examples thereof include those having 1 to 9 carbon atoms in the alkyl group which can be selected as R ^1b and R ^3b described above. When the carbon number of the acyl group is 10 or less, compatibility with the refrigerant is improved. The preferred acyl group has 2 to 4 carbon atoms.

When R ^1b and R ^3b are both a hydrocarbon group or an acyl group, R ^1b and R ^3b may be the same or different from each other.

Furthermore, when n is 2 or more, a plurality of R ^3b in one molecule may be the same or different.

When R ^1b is a hydrocarbon group having 1 to 10 carbon atoms having 2 to 6 bonding sites, the hydrocarbon group may be either a straight chain or a cyclic group. The hydrocarbon group having two bonding sites is preferably an aliphatic hydrocarbon group, and examples thereof include an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, a heptylene group, an octylene group, a nonylene group, And a cyclohexylene group. Examples of the other hydrocarbon groups include residues obtained by removing hydroxyl groups from bisphenols such as biphenol, bisphenol F, and bisphenol A. The hydrocarbon group having 3 to 6 bonding sites is preferably an aliphatic hydrocarbon group, and examples thereof include trimethylolpropane, glycerin, pentaerythritol, sorbitol, 1,2,3-trihydroxycyclohexane, 1,3,5-trihydroxycyclohexane, and other residues obtained by removing a hydroxyl group from a polyhydric alcohol.

When the carbon number of the aliphatic hydrocarbon group is 10 or less, compatibility with the refrigerant is improved. The preferred number of carbon atoms of the aliphatic hydrocarbon group is 2 to 6.

Examples of the oxygen-containing hydrocarbon group having 1 to 10 carbon atoms in each of R ^1b and R ^3b include a chain aliphatic group having an ether bond or a cyclic aliphatic group (e.g., tetrahydrofurfuryl group) have.

At least one of R ^1b and R ^3b is preferably an alkyl group, particularly an alkyl group having 1 to 4 carbon atoms.

R ^2b in the formula (B-1) is an alkylene group having 2 to 4 carbon atoms, and examples of the oxyalkylene group as the repeating unit include an oxyethylene group, an oxypropylene group and an oxybutylene group. The oxyalkylene group in one molecule may be the same or two or more oxyalkylene groups may be contained, but it is preferable that at least one oxypropylene unit is contained in one molecule, and an oxypropylene unit in an oxyalkylene unit is contained in an amount of 50 mol% It is more preferable to include them.

N in the formula (B-1) is an integer of 1 to 6 and is determined according to the number of bonding sites of R ^1b . For example, when R ^1b is an alkyl or acyl group, n is 1 and R ^1b is an aliphatic hydrocarbon group having 2, 3, 4, 5, and 6 linking moieties, n is 2, 3, 4, 5, 6. Further, m is a number in which the average value of m x n is 6 to 80. The average value is 80 or less so that the compatibility is good. Also, n is preferably an integer of 1 to 3, more preferably 1. However, it is preferable that the average value of mxn is appropriately set so as to be a viscosity range of a base oil to be described later.

The polyoxyalkylene glycols represented by the above formula (B-1) include polyoxyalkylene glycols having a hydroxyl group at the terminal, and the content of the hydroxyl group is not more than 50 mol% , It can be suitably used.

Copolymers of poly (oxy) alkylene glycols or monoethers thereof with polyvinyl ethers (ECP)

As the copolymer of poly (oxy) alkylene glycol or monoether and polyvinyl ether thereof, which can be used as a base oil in the refrigerating machine oil of the present embodiment, a copolymer represented by the following formula (C-1) , And a copolymer represented by the formula (C-2) (hereinafter referred to as polyvinyl ether copolymer I and polyvinyl ether copolymer II, respectively). On the other hand, poly (oxy) alkylene glycols refer to both polyalkylene glycols and polyoxyalkylene glycols.

Each of R ^1c , R ^2c and R ^3c in the formula (C-1) independently represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, and they may be the same or different, and R ^5c is a hydrocarbon group having 2 to 4 carbon atoms R ^2c is an aliphatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms, an aromatic hydrocarbon group having 1 to 20 carbon atoms, an acyl group having 2 to 20 carbon atoms, or an oxygen-containing hydrocarbon group having 2 to 50 carbon atoms, R ^4c is a divalent hydrocarbon group, And R &lt; ^1c &^gt; to R &lt; ^6c &^gt; may be the same or different from each other when they are plural.

Here, the hydrocarbon group having 1 to 8 carbon atoms in R ^1c to R ^3c is specifically a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec- , Various pentyl groups, various hexyl groups, various heptyl groups, and various octyl groups; Cycloalkyl groups such as cyclopentyl group, cyclohexyl group, various methylcyclohexyl groups, various ethylcyclohexyl groups and various dimethylcyclohexyl groups; Aryl groups such as various dimethylphenyl groups; Benzyl group, various phenylethyl groups, and various methylbenzyl groups. On the other hand, as each of R ^1c , R ^2c and R ^3c , a hydrogen atom is particularly preferable.

Specific examples of the divalent hydrocarbon group having 2 to 4 carbon atoms represented by R ^5c include divalent alkylene groups such as a methylene group, an ethylene group, various propylene groups, and various butylene groups.

On the other hand, in the formula (C-1), v represents the number of repeating R ^5c O and the average value thereof is 1 to 50, preferably 1 to 20, more preferably 1 to 10, &Lt; / RTI &gt; R ^5c in the case where O is plural, plural R ^5c is O may be the same or different. v may be the same or different for each constituent unit.

W is 1 to 50, preferably 1 to 10, more preferably 1 to 2, particularly preferably 1, u is 0 to 50, preferably 2 to 25, more preferably 5 to 15 And w and u may be a block or random if there are a plurality of them.

Furthermore, R ^6c in the formula (C-1) preferably represents an alkyl group having 1 to 10 carbon atoms, an acyl group having 2 to 10 carbon atoms, or an oxygen-containing hydrocarbon group having 2 to 50 carbon atoms.

Specific examples of the alkyl group having 1 to 10 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, Examples of the alkyl group include a methyl group, an ethyl group, an ethyl group, an ethyl group, an ethyl group, an ethyl group, an ethyl group, an ethyl group, an ethyl group, a propyl group, And so on.

Examples of the acyl group having 2 to 10 carbon atoms include an acetyl group, a propionyl group, a butyryl group, an isobutyryl group, a valeryl group, an isovaleryl group, a pivaloyl group, a benzoyl group and a toluyl group.

Specific examples of the oxygen-containing hydrocarbon group having 2 to 50 carbon atoms include methoxymethyl group, methoxyethyl group, methoxypropyl group, 1,1-bismethoxypropyl group, 1,2-bismethoxypropyl group, ethoxy Propyl group, (2-methoxyethoxy) propyl group, and (1-methyl-2-methoxy) propyl group.

Specific examples of the hydrocarbon group having 1 to 10 carbon atoms represented by R ^4c in the formula (C-1) include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, , Various hexyl groups, various heptyl groups, various octyl groups, various nonyl groups, and various decyl groups; Cycloalkyl groups such as cyclopentyl group, cyclohexyl group, various methylcyclohexyl groups, various ethylcyclohexyl groups, various propylcyclohexyl groups, and various dimethylcyclohexyl groups; Aryl groups such as a phenyl group, various methylphenyl groups, various ethylphenyl groups, various dimethylphenyl groups, various propylphenyl groups, various trimethylphenyl groups, various butylphenyl groups, and various naphthyl groups; An arylalkyl group such as a benzyl group, various phenylethyl groups, various methylbenzyl groups, various phenylpropyl groups, and various phenylbutyl groups.

The polyvinyl ether copolymer I having the constituent unit represented by the above-mentioned formula (C-1) is a copolymer, so that it can improve lubricity, insulation, hygroscopicity and the like while satisfying compatibility.

On the other hand, in the polyvinyl ether copolymer II represented by the above formula (C-2), R ^1c to R ^5c and v are as defined above. R ^4c and R ^5c may be the same or different from each other when they are plural. x and y each represent a number of 1 to 50, and x and y may be a block or random if there are a plurality of them. X ^c and Y ^c each independently represent a hydrogen atom, a hydroxyl group or a hydrocarbon group of 1 to 20 carbon atoms.

On the other hand, it is preferable that the repeating number u, w, x, and y in the formulas (C-1) and (C-2) are suitably selected so as to be a desired viscosity to be described later. The method for producing the polyvinyl ether copolymers I and II is not particularly limited as long as it is a method for obtaining the same.

The vinyl ether copolymer I represented by the general formula (C-1) is a copolymer of one terminal end thereof represented by the following formula (C-3) or (C-4) -5) or the formula (C-6).

(In (C-3) and (C-4), R ^1c to R ^6c and v are as defined above.)

(In the above (C-5) and (C-6), R ^1c to R ^6c and v are as defined above.)

<Polyol Esters (POE)>

As the polyol esters usable as the base oil in the refrigerator oil, a polyol having 3 to 20 diols or hydroxyl groups and an ester of a fatty acid having 1 to 24 carbon atoms are preferably used. Examples of the diol include ethylene glycol, 1,3-propanediol, propylene glycol, 1,4-butanediol, 1,2-butanediol, 2-methyl 1,3-propanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 2-ethyl- Methyl-2-propyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol, 1,8-octanediol 1,9-nonene diol, 1,10-decene diol, 1,11-undecene diol, 1,12-dodecane diol, and the like. Examples of the polyol include polyols such as trimethylolethane, trimethylol propane, trimethylolbutane, di (trimethylolpropane), tri (trimethylolpropane), pentaerythritol, ), Tri (pentaerythritol), glycerin, polyglycerin (2 to 20 moles of glycerin), 1,3,5-pentanetriol, sorbitol, sorbitan, sorbitol glycerin condensate, adonitol, Xanthol, and mannitol; and a polyhydric alcohol such as xylose, arabinose, ribose, rhamnose, glucose, fructose, galactose, mannose, sorbose, cellobiose, maltose, isomaltose, trehalose, sucrose, raffinose, Saccharides such as carboxymethylcellulose, carboxymethylcellulose, carboxymethylcellulose, hydroxypropylcellulose, hydroxypropylcellulose, hydroxypropylcellulose, hydroxypropylcellulose, hydroxypropylcellulose, Among them, polyols such as neopentyl glycol, trimethylolethane, trimethylol propane, trimethylolbutane, di (trimethylolpropane), tri (trimethylolpropane), pentaerythritol, di (Pentaerythritol), and tri (pentaerythritol).

As the fatty acid, the number of carbon atoms is not particularly limited, but usually 1 to 24 carbon atoms is used. Among fatty acids having 1 to 24 carbon atoms, from the viewpoint of lubricity, the number of carbon atoms is preferably 3 or more, more preferably 4 or more carbon atoms, and even more preferably 5 or more carbon atoms. In terms of compatibility with the refrigerant, the carbon number is preferably 18 or less, more preferably 12 carbon atoms or less, and even more preferably 9 carbon atoms or less.

In addition, it may be either a linear fatty acid or a branched fatty acid, and a linear fatty acid is preferable in terms of lubricity, and a branched fatty acid is preferable in terms of hydrolytic stability. Further, it may be either saturated fatty acid or unsaturated fatty acid.

Examples of the fatty acid include fatty acid such as isobutyric acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, pentadecanoic acid, hexadecanoic acid , Heptadecanoic acid, octadecanoic acid, nonadecanoic acid, eicosanoic acid, oleic acid and the like, or so-called neo-acids in which the carbon atom is? More specifically, there can be mentioned isobutyric acid, valeric acid (n-pentanoic acid), caproic acid (n-hexanoic acid), enanthic acid (n- n-nonanoic acid), capric acid (n-decanoic acid), oleic acid (cis-9-octadecenoic acid), isopentanoic acid (3-methylbutanoic acid) 2-ethylhexanoic acid, 3,5,5-trimethylhexanoic acid, and the like are preferable.

On the other hand, as the polyol ester, all of the hydroxyl groups of the polyol may not be esterified, the remaining partial esters may be used, all hydroxyl groups may be esterified complete esters, or may be a mixture of partial esters and complete esters.

Among these polyol esters, since the hydrolytic stability is more excellent, it is preferable to use polyol esters such as neopentyl glycol, trimethylol ethane, trimethylol propane, trimethylol butane, di (trimethylol propane), tri Esters of hindered alcohols such as pentaerythritol, pentaerythritol, di (pentaerythritol) and tri (pentaerythritol) are more preferable, and neopentyl glycol, trimethylolethane, trimethylolpropane, tri The ester of methyl oleate and pentaerythritol is more preferred, and the compatibility with refrigerant and the hydrolytic stability are particularly excellent, so that the ester of pentaerythritol is most preferable.

Specific examples of preferred polyol esters include neopentyl glycol and isobutyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, oleic acid, isopentanoic acid, 2- A diester of one or more fatty acids selected from 2-ethylpentanoic acid, 2-ethylhexanoic acid, and 3,5,5-trimethylhexanoic acid, a diester of trimethylolethane and isobutyrate, valeric acid, 2-ethylhexanoic acid, 2-ethylhexanoic acid, 3,5,5-trimethylhexanoic acid, 2-ethylhexanoic acid, 2-ethylhexanoic acid, , Triethylol propane and isobutyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, oleic acid, isopentanoic acid , 2-methylhexanoic acid, 2-ethylpentanoic acid, 2-ethylhexanoic acid, 3,5,5-trimethylhexanoic acid Triisostearic acid, isostearic acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, oleic acid, isopentanoic acid, Triester of one or more fatty acids selected from 2-methylhexanoic acid, 2-ethylpentanoic acid, 2-ethylhexanoic acid and 3,5,5-trimethylhexanoic acid, pentaerythritol and isobutyric acid, Butyric acid, 2-ethylpentanoic acid, 2-ethylhexanoic acid, 3,5,5-hexanetetracarboxylic acid, and the like. -Tetramethylhexanoic acid, and tetraester of one or two or more kinds of fatty acids selected from trimethylhexanoic acid.

On the other hand, the ester of two or more kinds of fatty acids may be a mixture of two or more kinds of esters of one kind of fatty acid and polyol, and an ester of two or more kinds of mixed fatty acids and polyol, especially mixed esters of fatty acid and polyol, Excellent compatibility with refrigerant.

The kinetic viscosity at 100 캜 of the oxygen-containing organic compound contained in the refrigerating machine oil is preferably 1 to 30 mm ² / s. When the kinematic viscosity is 1 mm ² / s or more, good lubrication performance is exhibited, and sealability is also improved. Further, when it is 30 mm ² / s or less, compatibility of refrigerant and refrigerator oil is excellent and energy saving is good. In the above aspect, kinematic viscosity of 100 ℃ Oxygenated organic compounds, and more preferably 2~20mm ² / s, more preferably 3~15mm ² / s.

On the other hand, the base oil may be composed only of the above-mentioned oxygen-containing organic compound, but it may contain, in addition to the oxygen-containing organic compound, a mineral oil, a synthetic oil other than the oxygen- . On the other hand, the base oil other than the oxygen-containing organic compound is preferably less than 10 mass%, more preferably less than 5 mass%, further preferably less than 1 mass%, based on the freezer flow rate. Like the base oil it should also Oxygenated organic compounds other than oxygen, an organic compound, the kinematic viscosity 100 ℃, preferably 1~30mm ² / s, more preferably 2~20mm ² / s, more preferably 3~15mm ² / s.

[Diphosphonic acid ester compound]

The polyphosphoric acid ester compound contained in the refrigerating machine oil of the present embodiment is a phosphate ester compound having at least two phosphoric acid skeletons in one molecule. The polyphosphate ester compound is specifically a compound represented by the following formula (1).

(Wherein, in the formula (1), n represents an integer of 1 to 10, R ¹ to R ⁸ each independently represent a hydrogen atom or an alkyl group of 1 to 20 carbon atoms, and R ⁹ represents an alkyl group of 2 to 20 Of the divalent hydrocarbon group.

The refrigerating machine oil of the present embodiment contains the above-described polyphosphoric acid ester compound and a benzotriazole-based compound described below, thereby reducing the friction coefficient in the sliding portion of the refrigerator and improving the wear resistance.

On the other hand, the polyphosphoric acid ester compound may be used singly or in combination of two or more.

In the formula (1), the alkyl group in R ¹ to R ⁸ may be any of linear, branched and cyclic, and may be a methyl group, ethyl group, n-propyl group, isopropyl group, various butyl groups, , Various hexyl groups, various heptyl groups, various octyl groups, various nonyl groups, various decyl groups, various undecyl groups, various dodecyl groups, various tridecyl groups, various tetradecyl groups, various pentadecyl groups, various hexadecyl groups, A heptadecyl group, and various octadecyl groups.

R ¹ to R ⁸ are preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or a methyl group, and most preferably a hydrogen atom.

R ⁹ in the formula (1) is preferably an alkylene group, an arylene group, or a hydrocarbon group consisting of an arylene group and an alkylene group, and preferably includes an arylene group. When R ⁹ is an alkylene group, the alkylene group may be, for example, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, a heptylene group, an octylene group, a nonylene group, A dodecylene group, a tetradecylene group, a hexadecylene group, an octadecylene group, and an icosalene group, and they may be linear or branched. The alkylene group may also be a cyclic alkylene group such as a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, a cyclohexylene group, a cycloheptylene group, a cyclooctylene group, a dicyclopentylene group, and a tricyclopentylene group.

Examples of the arylene group include a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, a substituted or unsubstituted biphenyl group and the like, but aryl It is preferable that the ring is not unsubstituted. Among them, a phenylene group is preferable.

When R ⁹ is composed of an arylene group and an alkylene group, the arylene group is the same as the above, and as the alkylene group, a straight chain, branched chain or cyclic alkylene group having 1 to 14 carbon atoms can be exemplified, For example, a methylene group or the same one as described above can be used. The alkylene group is preferably a linear or branched alkylene group having 1 to 5 carbon atoms. Specific examples thereof include methylene group, various ethylene groups such as 1,1-ethylene and 1,2-ethylene, 1,3-propylene, 1 , Various propylene groups such as 2-propylene and 2,2-propylene, various butylene groups and various pentylene groups. Of these, 2,2-propylene group (-C (CH ₃ ) ₂ - Do.

In the formula (1), n is preferably 1 to 8, and n may be a single group consisting of a specific one or may be a mixture of two or more specific groups of n. n is more preferably 1 to 3, and n is particularly preferably 1. By making n smaller, the molecular weight becomes smaller, so the solubility in the base oil can be easily increased and the coefficient of friction can be easily reduced.

A preferable example of R ⁹ is a group represented by the following formulas (2) to (4), but the group represented by the formula (2) or (3) is more preferable and the group represented by the formula More preferable. On the other hand, the formula (2) may be an ortho, meta, or para, but a meta is preferable.

Specific examples of preferred polyphosphate ester compounds include compounds represented by the following formulas (5) and (6). Among them, compounds represented by the following formula (5) are more preferable.

In the formula (5), n represents an integer of 1 to 10, preferably 1 to 8, more preferably 1 to 5. On the other hand, in the case where the base oil contains PVE as the oxygen-containing organic compound, the polyphosphoric acid ester compound represented by the formula (5) easily exhibits the effect of improving abrasion resistance and reducing the coefficient of friction, Is 1 to 3, particularly when n is 1, the effect is easily exhibited.

The content of the polyphosphate ester compound is preferably 0.01 to 5.0% by mass with respect to the flow rate of the refrigerator. In the present embodiment, by containing the polyphosphoric acid ester compound in an amount of 0.01 mass% or more, it is possible to effectively reduce the friction coefficient in the sliding portion while maintaining the stability and abrasion resistance of the refrigerator oil well. On the other hand, when the content is 5.0 mass% or less, it is easy to dissolve the polyphosphoric acid ester compound in the base oil, and the effect depending on the content can be easily exhibited.

The content of the polyphosphoric acid ester compound is more preferably 0.5 to 5.0 mass%, more preferably 1.0 to 5.0 mass%, and most preferably 1.0 to 5.0 mass%, in order to effectively reduce the friction coefficient in the sliding portion while taking the stability and wear resistance of the freezer oil into consideration. , More preferably from 1.0 to 3.0 mass%.

[Benzotriazole-based compound]

Examples of the benzotriazole-based compound contained in refrigerator oil include benzotriazole and benzotriazole derivatives.

Specifically, benzotriazole is 1,2,3-benzotriazole represented by the formula (7). Examples of derivatives of benzotriazole include alkylbenzotriazole represented by the following formula (8) and aminoalkyl benzotriazole represented by the following formula (9).

In formula (8), R ¹¹ represents a linear or branched alkyl group having 1 to 4 carbon atoms, and a represents an integer of 1 to 3. When there are a plurality of R &lt; ^{11 &} gt ;, they may be the same or different. Specific examples of R ¹¹ include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl.

R ¹¹ is preferably a methyl group or an ethyl group, and a is preferably 1 or 2, and more preferably 1.

Further, in the formula (9), R ¹² is an alkyl group having 1 to 4 carbon atoms straight-chain or branched, b is an integer, of 0 to 3 R ¹³ is a methylene group or an ethylene group, R ¹⁴ and R ¹⁵ are each independently A hydrogen atom, or a linear or branched alkyl group having 1 to 18 carbon atoms. When there are a plurality of R ¹² , they may be the same or different. R ¹⁴ and R ¹⁵ may be the same or different.

Examples of the alkyl group for R ¹² include a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group and tert-butyl group. Examples of the alkyl group represented by R ¹⁴ and R ¹⁵ include a methyl group, an ethyl group, a propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group, Various heptadecyl groups, various pentadecyl groups, various hexadecyl groups, various heptadecyl groups, hexadecyl groups, octadecyl groups, hexadecyl groups, and various heptadecyl groups. An alkyl group such as a methyl group, an ethyl group, an octyl group, and an octadecyl group.

R ¹² is preferably a methyl group or an ethyl group, R ¹⁴ and R ¹⁵ are preferably an alkyl group having 1 to 12 carbon atoms linear or branched, b preferably represents a number of 0 or 1.

As the compound represented by the formula (9), R ¹² is a methyl group, b is 0 or 1, R ¹³ is a methylene group or an ethylene group, R ¹⁴ and R ¹⁵ are a linear or branched alkyl group having 1 to 12 carbon atoms a dialkylamino alkyl benzotriazole or a dialkylamino-alkyl-tolyl preferably a triazole or a mixture thereof, and among them, it is more preferred that R ¹⁴ and R ¹⁵ has 4 to 12 carbon atoms each.

On the other hand, the benzotriazole-based compounds may be used singly or in combination of two or more.

Specific examples of the benzotriazole compound include 1,2,3-benzotriazole, methylbenzotriazole, 1- [N, N-bis (2-ethylhexyl) aminomethyl] methylbenzotriazole, .

The content of the benzotriazole-based compound is preferably 0.01 mass% or more with respect to the flow rate of the refrigerator. In the present embodiment, it is possible to reduce the coefficient of friction while improving the abrasion resistance by using the polyphosphoric ester compound in combination with the content of 0.01 mass% or more. The content of the benzotriazole compound is more preferably 0.01 to 1.00 mass%, more preferably 0.02 to 1.00 mass%, in order to appropriately obtain these effects.

[Other additives]

The refrigerating machine oil according to the present embodiment may further contain an antioxidant, an acid scavenger, a defoaming agent, an extreme pressure agent, an oil agent, an oxygen scavenger, a metal deactivator, and an antirust agent, in addition to the polyphosphoric acid ester compound and the benzotriazole- And the like may be contained. That is, the refrigerating machine oil may be composed of a base oil, the polyphosphoric ester compound, and the benzotriazole compound, and may further comprise a base oil, the polyphosphoric acid ester compound, a benzotriazole compound, Or may be made of an additive. In this case, as described above, the base oil may contain, in addition to the oxygen-containing organic compound, a mineral oil and a synthetic oil other than the oxygen-containing organic compound, but is preferably composed of an oxygen-containing organic compound.

As the above-mentioned various additives, it is preferable to include one or more of antioxidants, acid scavengers and antifoaming agents among the above-mentioned various additives. The additive other than the polyphosphoric acid ester compound and the benzotriazole compound is contained in an amount of preferably 15% by mass or less, more preferably 0 to 5% by mass, based on the flow rate of the refrigerating machine.

Examples of the antioxidant include 2,6-di-tert-butyl-4-methylphenol, 2,6-di-tert- Butylphenol), and amine-based antioxidants such as phenyl-α-naphthylamine and N, N'-diphenyl-p-phenylenediamine. Phenolic antioxidants are preferred . The content of the antioxidant is usually from 0.01 to 5% by mass, preferably from 0.05 to 3% by mass, based on the flow rate of the refrigerator from the viewpoints of effects and economical efficiency.

Examples of the acid trapping agent include epoxy compounds such as phenyl glycidyl ether, alkyl glycidyl ether, alkylene glycol glycidyl ether, cyclohexene oxide,? -Olefin oxide, and epoxidized soybean oil . Of these, phenyl glycidyl ether, alkyl glycidyl ether, alkylene glycol glycidyl ether, cyclohexene oxide, and? -Olefin oxide are preferable from the viewpoint of compatibility.

The alkyl group of the alkyl glycidyl ether and the alkylene group of the alkylene glycol glycidyl ether may have a branch, and the number of carbon atoms is usually 3 to 30, preferably 4 to 24, 16. The? -Olefin oxide generally has a total carbon number of 4 to 50, preferably 4 to 24, in particular 6 to 16. In the present embodiment, the acid scavenger may be used alone or in combination of two or more. The content thereof is usually from 0.005 to 5% by mass, preferably from 0.05 to 3% by mass, based on the flow rate of the refrigerator from the viewpoints of the effect and the suppression of the occurrence of sludge.

In the present embodiment, the stability of the freezer oil can be improved by including an acid capturing agent.

Examples of the antifoaming agent include silicone antifoaming agents and fluorinated silicone antifoaming agents. The content of the antifoaming agent is usually 0.005 to 2% by mass, preferably 0.01 to 1% by mass, based on the flow rate of the refrigerator.

Examples of the extreme pressure agent include phosphorus-containing extreme pressure agents such as phosphoric acid esters, acidic phosphoric acid esters, phosphorous acid esters, acidic phosphorous acid esters and amine salts thereof.

These phosphorus-containing extreme pressure agents have one phosphorus atom in the molecule thereof and include triacyl phosphate, triisophenyl phosphate, tri (nonylphenyl) phosphite, diolylhydrogen phosphite, 2-ethylhexyldiphenyl Phosphite, and the like.

Examples of the extreme pressure agent include a metal salt of a carboxylic acid. The metal salt of the carboxylic acid referred to herein is preferably a carboxylic acid having 3 to 60 carbon atoms or a metal salt of a fatty acid having 3 to 30 carbon atoms, particularly 12 to 30 carbon atoms. Further, there may be mentioned dimer acid, trimer acid of fatty acid and metal salt of dicarboxylic acid having 3 to 30 carbon atoms. Of these, fatty acids having 12 to 30 carbon atoms and metal salts of dicarboxylic acids having 3 to 30 carbon atoms are particularly preferred.

On the other hand, the metal constituting the metal salt is preferably an alkali metal or an alkaline earth metal, and an alkali metal is particularly preferable.

Examples of the extreme pressure agent other than the above include, for example, sulfurized oils, sulfurized fatty acids, sulfurized esters, sulfurized olefins, dihydrocarbyl polysulfides, thiocarbamates, thiotripens, dialkyl thioiodipropionates It can be used as an anti-hypertensive agent.

The content of the extreme pressure agent is usually 0.001 to 5 mass%, particularly preferably 0.005 to 3 mass%, with respect to the flow rate of the refrigerator from the viewpoints of lubricity and stability.

These extreme pressure agents may be used alone or in combination of two or more.

Examples of oil-based agents include aliphatic saturated and unsaturated monocarboxylic acids such as stearic acid and oleic acid, polymerized fatty acids such as dimer acid and hydrogenated dimer acid, hydroxy fatty acids such as ricinoleic acid and 12-hydroxystearic acid, lauryl alcohol, Aliphatic saturated or unsaturated monocarboxylic acid amides such as aliphatic saturated or unsaturated monohydric alcohols such as aliphatic saturated or unsaturated alcohols, aliphatic saturated or unsaturated monoamines such as stearyl amine and oleyl amine, lauric acid amide and oleic acid amide, and polyhydric alcohols such as glycerin and sorbitol Alcohols and partial esters of aliphatic saturated or unsaturated monocarboxylic acids.

These may be used singly or in combination of two or more. The content thereof is usually selected in the range of 0.01 to 10% by mass, preferably 0.1 to 5% by mass, based on the flow rate of the refrigerator.

Examples of the oxygen scavenger include 4,4'-thiobis (3-methyl-6-t-butylphenol), diphenylsulfide, dioctyldiphenylsulfide, dialkyldiphenylene sulfide, benzothiophene, dibenzothiophene, A sulfur aromatic compound such as phenothiazine, benzothiapyran, thiapyran, thianthrene, dibenzothiapyran and diphenylene disulfide, an aliphatic unsaturated compound such as various olefins, dienes, and trienes, a double bond , And the like.

Examples of the metal deactivator include N- [N, N'-dialkyl (alkyl group having 3 to 12 carbon atoms) aminomethyl] triazole and the like.

Examples of the rust preventive agent include metal sulfonates, aliphatic amines, organic phosphoric acid esters, organic phosphoric acid esters, organic sulfonic acid metal salts, organic phosphoric acid metal salts, alkenyl succinic acid esters and polyhydric alcohol esters.

The refrigerator oil according to the present embodiment may further contain various other known additives insofar as the object of the present invention is not impaired.

[Refrigerant]

The refrigerator oil according to the present embodiment is used under a refrigerant environment, specifically, it is mixed with a refrigerant and used as a refrigerator. That is, in the present embodiment, it is used in a refrigerator in the form of a refrigerator composition containing a refrigerant oil and a refrigerant. In the refrigerating machine composition, it is preferable that the amount of the refrigerant and the refrigerating machine oil used is in the range of 99/1 to 10/90, more preferably 95/5 to 30/70 in terms of the mass ratio of the refrigerant / refrigerating machine oil. When the mass ratio falls within the above range, the refrigeration ability and lubricity of the freezer can be made appropriate.

Examples of the refrigerant to be used include one or two or more selected from the group consisting of fluorinated hydrocarbons, natural refrigerants such as carbon dioxide, hydrocarbons, and ammonia.

<Fluorinated hydrocarbons>

Examples of the fluorinated hydrocarbons include saturated fluorinated hydrocarbon compounds (saturated HFC) and unsaturated fluorinated hydrocarbon compounds (HFO).

The saturated fluorinated hydrocarbon compound is usually a fluorine of an alkane of 1 to 4 carbon atoms, preferably a fluorine of an alkane of 1 to 3 carbon atoms, more preferably a fluorine of an alkane of 1 to 2 carbon atoms (methane or ethane) Do. Specific examples of the methane or ethane fluoride include trifluoromethane (R23), difluoromethane (R32), 1,1-difluoroethane (R152a), 1,1,1-trifluoroethane R143a), 1,1,2-trifluoroethane (R143), 1,1,1,2-tetrafluoroethane (R134a), 1,1,2,2-tetrafluoroethane (R134), 1 , And 1,1,2,2-pentafluoroethane (R125). Of these, difluoromethane and 1,1,1,2,2-pentafluoroethane are preferred.

These saturated fluorohydrocarbon compounds may be used singly or in combination of two or more. Examples of the case where two or more of them are used in combination include a mixed refrigerant obtained by mixing two or more saturated fluorinated hydrocarbon compounds having 1 to 3 carbon atoms or a mixed refrigerant obtained by mixing two or more kinds of saturated fluorinated hydrocarbon compounds having 1 to 2 carbon atoms .

Examples of the specific mixed refrigerant include a mixture of R32 and R125 (R410A), a mixture of R125 and R143a and R134a (R404A), a mixture of R32 and R125 and R134a (R407A, R407C and R407E), a mixture of R125 and R143a .

Examples of the unsaturated fluorinated hydrocarbon compound include those having a carbon-carbon double bond such as linear or branched chain olefins having 2 to 6 carbon atoms and fluorides of cyclic olefins having 4 to 6 carbon atoms.

More specifically, it is possible to use ethylene containing 1 to 3 fluorine atoms, propene containing 1 to 5 fluorine atoms, butene having 1 to 7 fluorine atoms introduced therein, pentene having 1 to 9 fluorine atoms introduced therein, Hexene in which a fluorine atom is introduced, cyclobutene in which 1 to 5 fluorine atoms are introduced, cyclopentene in which 1 to 7 fluorine atoms are introduced, and cyclohexene in which 1 to 9 fluorine atoms are introduced.

Among these unsaturated fluorinated hydrocarbon compounds, fluorine of propene is preferable, propene having 3 to 5 fluorine atoms is more preferable, and propene having 4 fluorine atoms is most preferable. Specifically, 1,3,3,3-tetrafluoropropene (HFO1234ze) and 2,3,3,3-tetrafluoropropene (HFO1234yf) are preferable compounds.

These unsaturated fluorinated hydrocarbon compounds may be used alone, or two or more of them may be used in combination, or may be used in combination with a refrigerant other than the unsaturated fluorinated hydrocarbon compound. Here, as a case of using in combination with a refrigerant other than the unsaturated fluorinated hydrocarbon compound, a mixed refrigerant of a saturated fluorinated hydrocarbon compound and an unsaturated fluorinated hydrocarbon compound can be used. Specific examples of the mixed refrigerant include R-32, mixed refrigerant of HFO1234ze and R152a (AC5, mixing ratio: 13.23: 76.20: 9.96), and the like.

<Natural refrigerant>

Examples of natural refrigerants include hydrocarbons such as carbon dioxide (carbon dioxide gas), propane, n-butane, isobutane, 2-methylbutane, n-pentane, cyclopentane, isobutane, Ammonia, and one of these may be used alone, or two or more of them may be used in combination, or may be combined with a refrigerant other than a natural refrigerant. Examples of the case where it is used in combination with a refrigerant other than a natural refrigerant include a saturated fluorinated hydrocarbon compound, an unsaturated fluorinated hydrocarbon compound, or a mixed refrigerant with both of them. Specific examples of the mixed refrigerant include carbon dioxide, a mixed refrigerant of HFO1234ze and R134a (AC6, blending ratio of 5.15: 79.02: 15.41), and the like.

In the present embodiment, among these refrigerants, fluorinated hydrocarbons are preferable, and saturated fluorinated hydrocarbons are more preferable. The refrigerant may be a mixture of a saturated fluorinated hydrocarbon compound and another refrigerant, but it is preferable that the refrigerant is composed only of a saturated fluorinated hydrocarbon compound. Among them, R32, R125 and a mixture thereof, R410A, are more preferable. In this case, the ratio of R32 in the entire refrigerant is preferably 50 mass% or more, more preferably 70 mass% or more, and most preferably 100 mass% or R32 A single refrigerant is most preferred.

[Freezer]

The composition for a refrigerator oil or a refrigerator according to the present embodiment is used by being filled in a freezer. Here, the refrigerator has a refrigeration cycle comprising a compressor, a condenser, an expansion mechanism (expansion valve and the like) and an evaporator, or a constitution in which a compressor, a condenser, an expansion mechanism, a drier and an evaporator are essential. The refrigeration oil is used for lubrication of, for example, a sliding portion provided in a compressor or the like.

On the other hand, the sliding portion of the refrigerator is preferably made of metal-metal, and examples of the metal of the sliding portion include iron and steel. The refrigerator oil of the present embodiment can reduce the coefficient of friction while improving wear resistance between steel and steel.

More specifically, the composition for the refrigerator oil and the refrigerator may include various refrigerator systems such as a car air conditioner, a gas heat pump (GHP), an air conditioner, a refrigerator, a vending machine, a showcase, a hot water heater, , And heating systems.

[Manufacturing method of refrigerator oil]

The method for manufacturing refrigerator oil according to one embodiment of the present invention is to produce refrigerator oil by blending at least the polyphosphoric acid ester compound and the benzotriazole-based compound into the base oil containing the oxygen-containing organic compound. Further, in the present method, in addition to the polyphosphoric acid ester compound and the benzotriazole compound, any one or more of the above-mentioned various additives may be blended. The detailed description of the base oil, the polyphosphoric acid ester compound, the benzotriazole compound, and the various additives is the same as the above, and the description thereof is omitted.

Example

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples, but the present invention is by no means limited by these Examples. On the other hand, characteristics of base oil composition, composition of refrigerator oil and composition of refrigerator were obtained according to the following description.

(1) Kinematic viscosity

The measurement was conducted using a glass tube type viscometer according to JIS K2283: 2000.

(2) Lubrication test

Under a refrigerant environment of R32 (difluoromethane), the frictional coefficient and the wear amount of the sliding portion of each refrigerator composition were measured under the following conditions using a block-on-on-one friction tester (LFW-1) .

Ring: FC250 Block: SKH51 Number of rotations: 1000rpm

Strengthening: Load 300N × 1 minute Load: 500N Time: 30 minutes Oil temperature: 80 ° C

Refrigerant pressure: 0.4 MPa

Examples 1 to 16 and Comparative Examples 1 to 16

The refrigerator oil of each of the examples and comparative examples shown in Table 1 and the refrigerator oil composition of the refrigerating machine oil were adjusted to perform lubricity tests. The results are shown in Table 1.

In each of the examples and comparative examples, base oils and additives are as follows.

[Base oil]

PVE: a copolymer of ethylvinylether and isobutylvinylether (molar ratio of 9: 1, kinematic viscosity at 100 占 폚 of 7.8 mm ² / s), both ends of which are represented by the formulas (A-1-i) and (A- , R ^6a to R ^8a and R ^11a to R ^13a are hydrogen atoms, and all of r 1 and r 2 are 0, and R ^10a and R ^15a are an ethyl group or an isobutyl group.

PAG: polyoxypropylene glycol (100 占 폚 kinematic viscosity 9.8 mm ² / s)

ECP: polypropylene glycol (PPG) / polyethyl vinyl ether (PEV) copolymer (PPG / PEV molar ratio 5/5, 100 캜 kinematic viscosity 11.2 mm ² / s)

POE: pentaerythritol octanoic acid (C8 acid) nonanoic acid (C9 acid) ester (C8 acid / C9 acid molar ratio of 1 / 1.1, 100 ℃ kinematic viscosity 8.6mm ² / s)

[additive]

Polyphosphoric acid ester compound 1: A compound in which n is 1 to 3 in the above formula (5)

Polyphosphoric acid ester compound 2: Compound in which n in the formula (5) is a mixture of 1 to 8

Polyphosphoric acid ester compound 3: Compound represented by the above formula (6)

Wherein R ¹ , R ³ , R ⁵ and R ⁷ are each a hydrogen atom and R ² , R ⁴ , R ⁶ and R ⁸ are each a C 1-20 alkyl group, , R &lt; ⁹ &gt; is a divalent hydrocarbon group having 2 to 20 carbon atoms, and n is a mixture of 1 to 8 carbon atoms.

Benzotriazole compound 1: 1,2,3-benzotriazole

Benzotriazole-based compound 2: methylbenzotriazole

Benzotriazole compound 3: 1- [N, N-bis (2-ethylhexyl) aminomethyl] methylbenzotriazole

Antioxidant: 2,6-di-tert-butyl-4-methylphenol (DBPC)

Acid capturing agent: 2-ethylhexyl glycidyl ether

Defoamer: Silicone defoamer

As is clear from the results of the lubricity tests of Examples 1 to 16, it is possible to reduce the coefficient of friction in the sliding portion of the freezer by including both the phosphate ester compound and the benzotriazole-based compound in the freezer oil. In addition, as is clear from the fact that the ring wear amount was small, wear resistance was also improved.

On the other hand, as shown in Comparative Examples 1 to 16, when either or both of the polyphosphoric ester compound and the benzotriazole-based compound is not contained in the refrigerating machine oil, both the abrasion resistance and the friction coefficient are improved I could not.

Claims (13)

A refrigerator oil comprising a base oil containing an oxygen-containing organic compound, a polyphosphoric ester compound, and a benzotriazole-based compound. The method according to claim 1,
Wherein the content of the polyphosphoric acid ester compound is 0.01 to 5.0 mass% with respect to the flow rate of the refrigerator. 3. The method according to claim 1 or 2,
Wherein the content of the benzotriazole compound is 0.01% by mass or more based on the flow rate of the refrigerating machine. 4. The method according to any one of claims 1 to 3,
Wherein the oxygen-containing organic compound is selected from the group consisting of polyvinyl ethers, polyoxyalkylene glycols, poly (oxy) alkylene glycols or copolymers thereof with monoethers and polyvinyl ethers, and polyol esters At least one selected refrigerator oil. 5. The method according to any one of claims 1 to 4,
Wherein the polyphosphoric acid ester compound is a compound represented by the following formula (1).

(Wherein, in the formula (1), n represents an integer of 1 to 10, R ¹ to R ⁸ each independently represent a hydrogen atom or an alkyl group of 1 to 20 carbon atoms, and R ⁹ represents an alkyl group of 2 to 20 carbon atoms Represents a divalent hydrocarbon group.) 6. The method of claim 5,
A refrigerator oil wherein R ⁹ in the formula (1) comprises an arylene group. The method according to claim 5 or 6,
Wherein R ⁹ in the formula (1) is any one represented by the following formula (2) or (3).

8. The method according to any one of claims 1 to 7,
Wherein the polyphosphoric acid ester compound is at least one selected from the group consisting of compounds represented by the following formulas (5) and (6).

(In the formula (5), n represents an integer of 1 to 10.)

9. The method according to any one of claims 1 to 8,
Wherein the benzotriazole-based compound is at least one selected from the group consisting of compounds represented by the following formulas (7) to (9).

(In the formula (8), R ¹¹ represents a linear or branched alkyl group having 1 to 4 carbon atoms, and a represents an integer of 1 to 3. When there are a plurality of R ¹¹ , they may be the same or different. in the formula (9), R ¹² is an alkyl group having 1 to 4 carbon atoms straight-chain or branched, b is an integer of 0 to 3, R ¹³ is a methylene group or an ethylene group, R ¹⁴ and R ¹⁵ are each independently a hydrogen atom , Or a linear or branched alkyl group having 1 to 18 carbon atoms.) A refrigerator composition comprising a refrigerant and the refrigerator oil according to any one of claims 1 to 9. 11. The method of claim 10,
Wherein the refrigerant comprises one or more refrigerants selected from the group consisting of fluorohydrocarbons, carbon dioxide, hydrocarbons, and ammonia. The method according to claim 10 or 11,
Wherein the refrigerant comprises a saturated fluorinated hydrocarbon compound. Wherein a refrigerator oil is obtained by mixing at least a polyphosphoric acid ester compound and a benzotriazole-based compound in a base oil containing an oxygen-containing organic compound.