JPH08337792A - Hydraulic fluid composition for refrigerating machine - Google Patents

Abstract

PURPOSE: To inexpensively obtain the subject composition capable of diminishing the wear of metal contact surface, excellent in compatibility, thermal stability, electrical insulation and low hygroscopicity, generating no carboxylic acid due to its hydrolysis, comprising a specific base oil, a phosphorus compound and a hydrofluorocarbon. CONSTITUTION: This hydraulic fluid composition comprises (A) a lubricating oil composition comprising a base oil A1 mainly consisting of a cyclic ketal or cyclic acetal and a phosphorus compound A2 , i.e., a compound of formula I [X1 -X3 are each a 2-4C (branched) alkylene; X4 -X6 are each a l-l8C (halogenated) straight-chain alkyl, 3-18C branched alkyl, 2-l8C straight-chain alkenyl, 3-l8C branched alkenyl, 6-l8C (halo)aryl or 7-18C aralkyl; (p), (q) and (r) are each 0-30[ or formula II (X<7> and X<8> are each same as X<1> ; X<9> -X<11> are each same as X<4> ; (s) and (t) are each same as (p)) and (B) a hydrofluorocarbon.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a composition for a working fluid of a refrigerator having an excellent effect of suppressing wear. That is,
The present invention provides a composition for a working fluid of a refrigerator, which comprises a lubricating oil composition comprising a base oil containing a cyclic ketal or a cyclic acetal compound as a main component and a specific phosphorus compound, and hydrofluorocarbon.

[0002]

2. Description of the Related Art Recently, the use of dichlorodifluoromethane (CFC12), which is used in refrigerators and car coolers to protect the ozone layer, has been regulated, and it was decided that it will be prohibited by the end of 1995. In addition, chlorodifluoromethane (HCFC) that is subsequently used in room air conditioners, etc.
The use of 22) is about to be regulated. Therefore, as a substitute for CFC12 and HCFC22, hydrofluorocarbon (HF) that does not destroy the ozone layer is used.
C) type refrigerants such as 1,1,1,2-tetrafluoroethane (HFC134a) and difluoromethane (HFC32)
And pentafluoroethane (HFC125) have been developed.

Since these HFC-based refrigerants have a higher polarity than CFC12 and HCFC22, if naphthene-based mineral oils or poly-α-olefins, alkylbenzenes or other lubricating oils that have been commonly used as refrigerating machine oils are used. However, the compatibility between these lubricating oils and hydrofluorocarbons is poor, and two-layer separation occurs at low temperatures. When two-layer separation occurs, the oil return deteriorates and a thick oil film adheres to the vicinity of the condenser or evaporator as a heat exchanger to prevent heat transfer, and important defects such as poor lubrication and foaming at startup. Cause of. Therefore, the conventional refrigerating machine oil cannot be used as the refrigerating machine oil under these new refrigerant atmospheres.
Therefore, there is a need for a lubricating oil that has good compatibility with hydrofluorocarbons.

Also, regarding lubricity, CFC12 and HCF are also available.
In C22, there was an effect that it partially decomposed to generate hydrogen chloride, and this hydrogen chloride reacted with the friction surface to form a chloride film to improve lubricity. However, since such effects cannot be expected for hydrofluorocarbons that do not contain chlorine atoms, refrigerating machine oils used with hydrofluorocarbons are required to have lubricating oils with even better lubricity than conventional ones.

Further, as a refrigerating machine oil used together with hydrofluorocarbon, it is necessary that it has good thermal stability in the presence of hydrofluorocarbon. Moreover, in addition to this, in compression type refrigerators such as electric refrigerators and room air conditioners, there are organic materials used for motors such as insulating materials and enameled wires, so as a working fluid consisting of hydrofluorocarbon and refrigerator oil, However, it is necessary that these organic materials are not adversely affected and that the electrical insulation is also good.

Hydrofluorocarbons such as 1,1,1,
As a refrigerating machine oil that can be used with 2-tetrafluoroethane (HFC134a), US Pat. No. 4,755,316
JP-A-2-502385, JP-A-3-14894 (European Patent No. 377,122), JP-A-2-82780
Japanese Patent Publication (WO90 / 05172) and the like disclose polyalkylene glycol compounds.

Since the polyalkylene glycol-based compound has a higher polarity than the naphthene-based mineral oil, the compatibility with HFC134a at low temperature is certainly good. However,
As described in U.S. Pat. No. 4,755,316, the polyalkylene glycol-based compound has a problem that two-phase separation occurs when the temperature rises. Moreover, the polyalkylene glycol-based compound has some other problems. One is that it has poor electrical insulation. This is a very big problem and cannot be used in refrigerators for electric refrigerators and refrigerators for air conditioners in which the motor is built in the compressor. These compounds have been suggested for use in such car-free air conditioning applications. Another problem is that it is highly hygroscopic. Due to the water content in the polyalkylene glycol compound, the PET film or the like, which is an organic material, is hydrolyzed. By reducing the number of ether bonds per unit weight, electrical insulation can be improved and hygroscopicity can be reduced, but compatibility with hydrofluorocarbon becomes poor. Thus, an ether compound such as polyalkylene glycol cannot achieve both compatibility with hydrofluorocarbon, electrical insulation and hygroscopicity.

Ester compounds and carbonate compounds have been developed in order to improve the problems of the polyalkylene glycol compounds such as electric insulation and hygroscopicity. For example, 1,1,1,2-tetrafluoroethane (HFC13
As a refrigerating machine oil that can be used together with 4a), a mixed oil of a polyalkylene glycol compound and an ester oil is disclosed in US Pat. No. 4,851,144 (JP-A-2-276894) and JP-A-2-58693, Japanese Patent Laid-Open No. 3-505602 (WO90 / 12849), Japanese Patent Laid-Open No. 3-128991, Japanese Patent Laid-Open No. 3-128991
3-128992, JP 3-88892, JP 3-1790
No. 91 discloses ester oil. JP-A-2-1321
78, JP-A-3-149295, European Patent No. 42
Carbonate oil is disclosed in specification 1,298.

Ester-based compounds and carbonate-based compounds are excellent in compatibility with hydrofluorocarbons and also in thermal stability in the presence of hydrofluorocarbons. Compared with polyalkylene glycol-based compounds, it has extremely excellent electric insulation and also has considerably low hygroscopicity. However, compared with CFC12-mineral oil system, which is a conventional working fluid, both hydrofluorocarbon-ester oil system and hydrofluorocarbon-carbonate oil system have higher polarities of both freon and oil, and are likely to contain water.
Therefore, there is a problem that the ester hydrolyzes to generate a carboxylic acid, and the generated carboxylic acid corrodes a metal to cause abrasion. Further, the carbonate oil causes hydrolysis to generate non-condensable carbon dioxide, which causes a problem that the refrigerating capacity is lowered.

Particularly, in the room air conditioner, the refrigerant is exclusively filled in the field, so it is almost impossible to prevent the mixing of water unlike the case of the refrigerator which is filled in the factory. -Carbonate oil system is concerned about the reliability of room air conditioners.

Further, as a polyether compound in which the electrical insulation of polyalkylene glycol is improved, WO93 / 2
Japanese Patent No. 4435 discloses a polyvinyl ether compound. This polyvinyl ether compound is
It is obtained by polymerizing a vinyl ether-based monomer and hydrogenating it, and it is disclosed that it has good compatibility with hydrofluorocarbons and also has good electrical insulation. However, since polyvinyl ether compounds are synthesized by the polymerization method and the products have different molecular weights, some high molecular weight compounds may cause clogging of the capillary tube, and compatibility with hydrofluorocarbons. May worsen. Further, since the post-treatment method is complicated and an unstable vinyl ether-based monomer is used as a raw material, it is hard to say that a good yield is obtained.
In particular, those having a low degree of polymerization (polymerization degree of around 6) have a drawback that the yield is low. Further, the vinyl ether-based monomer is expensive because it is difficult to obtain the raw material depending on the structure.

On the other hand, examples of using a cyclic ketal or a cyclic acetal as a working fluid of a refrigerator are described in JP-A-4-320498 and JP-A-6-57243. The former is a ketal or acetal obtained from a monohydric alcohol or a dihydric alcohol and a ketone or an aldehyde, and it is described that the ketal or acetal is used by being mixed with an ester or polyalkylene glycol synthetic lubricating oil, and the latter is an intramolecular compound. It is a derivative of ester or carbonate of glycerin, trimethylolethane, trimethylolpropane, pentaerythritol containing a ketal or acetal group.
The former acetals and ketals have small molecular weights,
It has the drawback of having a low flash point and the drawback of having a low viscosity. Therefore, when it is mixed with an ester or an ether such as polyalkylene glycol, there is a drawback that the viscosity and the flash point are remarkably lowered. Further, the latter acetal and ketal have the drawback that they are expensive because they undergo two or more reaction steps in the production, and some have the drawback that they are highly pure and difficult to obtain. Furthermore, the latter specifically disclosed as acetals and ketals have two or more ether bonds in the molecule, and there is a problem that the electrical insulation is not sufficiently improved.

As described above, the hydrofluorocarbon-polyalkylene glycol type that has been developed so far has a problem in hygroscopicity and electric insulation, and the hydrofluorocarbon-ester type and the hydrofluorocarbon-carbonate type have a problem in hydrolysis resistance. , All systems are conventional CFC1
2-Compared to mineral oil type, it tends to contain water, causing deterioration of thermal stability, deterioration of organic materials, corrosion and wear of metals,
It is not a satisfactory refrigerator working fluid. In addition, since the polyvinyl ether compound has a high molecular weight compound because it has a molecular weight distribution, it has a drawback that compatibility is reduced, and there is a drawback that the raw material species are limited and it becomes expensive.

The ketals and acetals that have been reported so far have the drawbacks of low molecular weight and high price. On the other hand, addition of a specific phosphorus compound results in lubrication of cyclic ketals and cyclic acetals. No attempt has ever been made to improve its performance as an oil.

[0015]

The object of the present invention is not to have the above-mentioned drawbacks, namely, excellent compatibility with hydrofluorocarbons, thermal stability, electrical insulation, hygroscopicity, and hydrolysis. It is an object of the present invention to provide a composition for a working fluid of a refrigerator, which is free from the generation of carboxylic acid due to the like, has excellent lubricity by suppressing wear, and is inexpensive.

[0016]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventor has found that a specific phosphorus compound is added to a base oil containing a cyclic ketal or a cyclic acetal as a main component. The inventors have found that the above objects can be achieved, and have completed the present invention.

That is, the gist of the present invention is (1) (A) a base oil containing a cyclic ketal or a cyclic acetal as a main component, and (B) a general formula (I) and / or (I).
I)

[0018]

Embedded image

(In the formula, X ₁ , X ₂ and X ₃ have 2 to 5 carbon atoms.
4 represents a linear or branched alkylene group, and p, q and r represent 0 to 30. X ₄ , X ₅ and X ₆ may be the same or different and are a linear alkyl group having 1 to 18 carbon atoms, a branched chain alkyl group having 3 to 18 carbon atoms, or 2 to 2 carbon atoms. A straight chain alkenyl group having 18 carbon atoms, a branched chain alkenyl group having 3 to 18 carbon atoms, and 6 to 18 carbon atoms
Having an aryl group, an aralkyl group having a carbon number of 7 to 18, a halogenated alkyl group having a carbon number of 1 to 18,
Alternatively, it represents a halogenated aryl group having 6 to 18 carbon atoms. Further, X ₇ and X ₈ represents a linear or branched alkylene group having 2 to 4 carbon atoms, s and t represent 0 to 30.
X ₉ , X ₁₀ and X ₁₁ may be the same or different and are a linear alkyl group having 1 to 18 carbon atoms, a branched chain alkyl group having 3 to 18 carbon atoms, and 2 to 18 carbon atoms.
A straight chain alkenyl group having 3 to 18 carbon atoms, a branched chain alkenyl group having 3 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, an aralkyl group having 7 to 18 carbon atoms, and 1 to 1 carbon atoms.
Halogenated alkyl group having 18 or 6 to 1 carbon atoms
Represents a halogenated aryl group having 8. ) A lubricating oil composition comprising a phosphorus compound represented by the formula) and (C) a composition for a working fluid of a refrigerator containing hydrofluorocarbon, (2) (A) a cyclic ketal or a cyclic acetal as a main component The composition for refrigerating machine working fluid according to (1) above, which contains 0.01 to 5 parts by weight of the phosphorus compound (B) per 100 parts by weight of the base oil, (3) Cyclic ketal or The cyclic acetal comprises one or more polyhydric alcohols having an even valence of 4 to 8 and a general formula (III)

[0020]

[Chemical 6]

(Wherein R ₁ is a hydrogen atom or a carbon number of 1 to 1)
2 represents a straight chain, branched chain or cyclic alkyl group, R
₂ represents a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms. Alternatively, R ₁ and R ₂ may combine to form an alkylene group having 2 to 13 carbon atoms. However, in either case, the total carbon number of R ₁ and R ₂ is 1 to 13. ) A cyclic ketal or a cyclic acetal obtained from at least one of a ketal or an acetal which is a carbonyl compound represented by the above) or a reactive derivative thereof, or a composition for a working fluid of a refrigerator according to (1) above. (4) The composition for a refrigerator working fluid according to (3) above, wherein the polyhydric alcohol has no ether bond, (5) the polyhydric alcohol has one ether bond, 3) The composition for a working fluid of a refrigerator, (6) The polyhydric alcohol has a tetravalent or hexavalent carbon number of 4 to
The above (3) to (5) which are 25 saturated aliphatic alcohols.
The composition for refrigerator working fluid according to any one of (7), wherein the cyclic ketal or cyclic acetal is 1,3-
The composition for a refrigerator working fluid according to any one of (1) to (6) above, which comprises a dioxolane structure and / or a 1,3-dioxane structure, (8) a cyclic ketal or a cyclic acetal is represented by the formula (IV) or ( (1) to (1), which is one or more kinds of cyclic ketals or cyclic acetals represented by V).
(3) The composition for a working fluid of a refrigerator according to any one of the above,

[0022]

[Chemical 7]

(In the formula, R ₁ is a hydrogen atom or a carbon number of 1 to 1.
2 represents a linear, branched or cyclic alkyl group, R ₂
Represents a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms. Or R ₁ and R ₂ together form 2 carbon atoms
~ 13 alkylene groups may be formed. However, in either case, the total number of carbon atoms of R ₁ and R ₂ bonded to the same carbon atom is 1 to 13. (9) The cyclic ketal or cyclic acetal is one or more of the cyclic ketal or cyclic acetal represented by the formula (VI) or (VII), and the above (1) to
(3) The composition for a working fluid of a refrigerator according to any one of the above,

[0024]

Embedded image

(In the formula, R ₁ is a hydrogen atom or a carbon number of 1 to 1.
2 represents a linear, branched or cyclic alkyl group, R ₂
Represents a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms. Or R ₁ and R ₂ together form 2 carbon atoms
~ 13 alkylene groups may be formed. However, in either case, the total number of carbon atoms of R ₁ and R ₂ bonded to the same carbon atom is 1 to 13. (10) The mixing ratio of hydrofluorocarbon and lubricating oil composition is hydrofluorocarbon / lubricating oil composition =
The composition for a working fluid of a refrigerator according to any one of (1) to (9) above, wherein the composition is 50/1 to 1/20 (weight ratio).

The cyclic ketal or cyclic acetal used in the present invention is not particularly limited as long as it is a compound having a cyclic ketal structure or a cyclic acetal structure. Those obtained from the reactive derivative are preferable.

The valence of the polyhydric alcohol used as the raw material of the cyclic ketal or cyclic acetal used in the present invention is 4
Valence, hexavalent or octavalent is preferable, and tetravalent or hexavalent is more preferable. If the valence of the polyhydric alcohol is higher than 8, the resulting cyclic ketal or cyclic acetal may have too high a viscosity, and may have poor compatibility with hydrofluorocarbons. If the valence of the polyhydric alcohol is less than tetravalent, the molecular weight becomes too low and the boiling point
It is not preferable because it has a low flash point. If the valence of the polyhydric alcohol is odd, unreacted hydroxyl groups will always remain and the viscosity will increase, which is not preferable. Further, when the hydroxyl group remains, the compatibility with the hydrofluorocarbon deteriorates, which is not preferable. By making the unreacted hydroxyl group into an ether structure by an alkylation reaction, the viscosity and compatibility with hydrofluorocarbon can be improved, but this is not preferable because the number of reaction steps in production increases. In addition, this makes it difficult to obtain a high-purity product.

The polyhydric alcohol used as the starting material for the cyclic ketal or cyclic acetal preferably has 4 to 25 carbon atoms, more preferably 4 to 15 carbon atoms, and particularly preferably 4 to 1 carbon atoms.
0. If the polyhydric alcohol has more than 25 carbon atoms, the compatibility of the resulting cyclic ketal or cyclic acetal with the hydrofluorocarbon is unfavorable. If the polyhydric alcohol has less than 4 carbon atoms, the molecular weight will be too low, and the boiling point and flash point will be low, such being undesirable.

Specifically, erythritol, diglycerin, arabinose, ribose, sorbitol, mannitol, galactitol, iditol, talitol, allitol, 4,7-dioxadecane-1,2,9,10-tetraol, 5-methyl -4,7-Dioxadecane-1,2,9,10-tetraol, 4,7,10-trioxatridecane-1,2,12,13-tetraol, 1,6-dimethoxyhexane-2,3 Polyhydric alcohols such as 4,4,5-tetraol and 3,4-diethoxyhexane-1,2,5,6-tetraol, pentaerythritol, ditrimethylolethane, ditrimethylolpropane, dipentaerythritol, tripenta Erythritol, 2,9-diethyl-2,9-dihydroxymethyl-4,7-dioxadecane
-1,10-diol, 2,12-diethyl-2,12-dihydroxymethyl-5,8-dimethyl-4,7,10-trioxatridecane-1,13
-A hindered alcohol such as a diol.

Of these, 4,7-dioxadecane-1,2,9,10-
Tetraol, 5-methyl-4,7-dioxadecane-1,2,9,1
0-tetraol, 4,7,10-trioxatridecane-1,2,1
2,13-Tetraol, 1,6-dimethoxyhexane-2,3,4,5
-Tetraol, 3,4-diethoxyhexane-1,2,5,6-tetraol, 2,9-diethyl-2,9-dihydroxymethyl-
4,7-Dioxadecane-1,10-diol, 2,12-diethyl-
Polyhydric alcohols with two or more ether bonds, such as 2,12-dihydroxymethyl-5,8-dimethyl-4,7,10-trioxatridecane-1,13-diol, are easily available industrially. Rather, it requires several steps to manufacture, which is expensive and is not preferable.

The polyhydric alcohol used as the raw material of the cyclic ketal or cyclic acetal used in the present invention is preferably a saturated aliphatic alcohol. An unsaturated bond is not preferable because the resulting lubricating oil composition has poor thermal stability.

The polyhydric alcohol used as the starting material for the cyclic ketal or cyclic acetal used in the present invention is most preferably one having no ether bond in the molecule from the viewpoint of having good electric insulation. Even if it has an ether bond, only one is preferable. It is not preferable to have two or more, because the electrical insulating property will deteriorate. Specific examples of the polyhydric alcohol having no ether bond in the molecule include erythritol, sorbitol, mannitol, galactitol, iditol, talitol, allitol, pentaerythritol, and the like.
Specific examples of the polyhydric alcohol having the same are diglycerin, ditrimethylolpropane, ditrimethylolethane and the like.

When an alcohol having a high symmetry such as pentaerythritol is used, the melting point of the obtained cyclic ketal or cyclic acetal is high, and the melting point of the obtained lubricating oil composition is high, so that the refrigerator is used. Not preferred for working fluids.

The carbonyl compound used as the starting material for the cyclic ketal or cyclic acetal used in the present invention is a ketone or aldehyde represented by the general formula (III).

[0035]

[Chemical 9]

The ketone or aldehyde represented by the general formula (III) has 2 to 14 carbon atoms, preferably 2 to 11 carbon atoms, and more preferably 2 to 6 carbon atoms. If the carbon number exceeds 14, the resulting cyclic ketal or cyclic acetal has poor compatibility with hydrofluorocarbons,
Not preferred.

R ₁ represents a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms, preferably a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms. And more preferably a hydrogen atom or a linear, branched, or cyclic alkyl group having 1 to 5 carbon atoms. R ₂ represents a linear, branched, or cyclic alkyl group having 1 to 12 carbon atoms, preferably a linear, branched, or cyclic alkyl group having 1 to 8 carbon atoms, and more preferably 1 to 1 carbon atoms. 5 represents a linear, branched, or cyclic alkyl group. Alternatively, R ₁ and R ₂ may be combined to form an alkylene group having 2 to 13 carbon atoms, preferably 4 to 10 carbon atoms, and more preferably 4 to 5 carbon atoms.
However, in any of the above cases, the total carbon number of R ₁ and R ₂ is 1 to 13, preferably 1 to 10, and more preferably 1 to 5. R ₁ and R ₂ may be the same or different. When the carbon number of R ₁ or R ₂ exceeds 13, the compatibility of the obtained cyclic ketal or cyclic acetal with hydrofluorocarbon is deteriorated, which is not preferable. If the alkylene group formed by R ₁ and R ₂ together has more than 13 carbon atoms, the compatibility of the resulting cyclic ketal or cyclic acetal with the hydrofluorocarbon is unfavorable. Also, the compatibility with hydrofluorocarbons cyclic ketal or cyclic acetal obtained, R _1, an alkyl group of R ₂ is preferably branched or cyclic structure than linear structure, also, R ₁ and R ₂ becomes Ichisho It is more preferable not to form an alkylene group than to form an alkylene group.

Specifically, as the ketone in which R ₁ and R ₂ are alkyl groups, acetone, methyl ethyl ketone, methyl propyl ketone, diethyl ketone, methyl isopropyl ketone, methyl butyl ketone, ethyl propyl ketone, methyl-sec-butyl ketone, Methyl isobutyl ketone, ethyl isopropyl ketone, methyl tert-butyl ketone, methyl amyl ketone, ethyl butyl ketone, diisopropyl ketone, methyl isoamyl ketone, dipropyl ketone, isopropyl propyl ketone, methyl neopentyl ketone, ethyl tert-butyl ketone, methyl hexyl Ketone, ethylpentylketone, 6-methyl-2-heptanone, 4-methyl-3-heptanone, 2-methyl-3-heptanone, 5-methyl-3-heptanone, methylcyclohexylketone, methylheptylketone, ethi Lehexyl ketone, dibutyl ketone, diisobutyl ketone, methyl octyl ketone, methyl nonyl ketone, dipentyl ketone,
Examples thereof include methyldecyl ketone, methylundecyl ketone, dihexyl ketone, and 6,10-dimethyl-2-undecanone.

As the ketone in which R ₁ and R ₂ are taken together to form an alkylene group, cyclopropanone, cyclobutanone, cyclopentanone, cyclohexanone, 2-
Methylcyclopentanone, 3-methylcyclopentanone,
2-methylcyclohexanone, 3-methylcyclohexanone, 4-methylcyclohexanone, cycloheptanone, 2,
4-dimethylcyclohexanone, 2,6-dimethylcyclohexanone, cyclooctanone, 3-ethylcyclohexanone, 4-ethylcyclohexanone, 3,5,5-trimethylcyclohexanone, 2-tert-butylcyclohexanone, 4-te
Examples include rt-butylcyclohexanone, 2-isopropyl-4-methylcyclohexanone, cyclodecanone and cyclododecanone.

As the aldehyde in which R ₁ is a hydrogen atom, acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, valeraldehyde, isovaleraldehyde, 2-methylbutyraldehyde, caproaldehyde, 2-methylpentanal, 3-methylpentanal, 4-methylpentanal, 2-ethylbutanal, 2,3-dimethylbutanal, 3,3-dimethylbutanal, cyclopentylacetaldehyde, heptanal, 2-methylhexanal, 3-methylhexanal, 4 -
Methylhexanal, 5-methylhexanal, 2-ethylpentanal, cyclohexylaldehyde, octanal, 2-methylheptanal, 2-ethylhexanal, 2-
Propyl pentanal, 2,2,4-trimethyl pentanal, nonyl aldehyde, 3,5,5-trimethyl hexanal, decyl aldehyde, isodecyl aldehyde, 3,7-dimethyl octanal, 2-isopropyl-5-methyl hexanal, Examples include undecanal and dodecanal.

The ketone represented by the general formula (III) used in the present invention is a high temperature decarboxylation dimerization reaction of fatty acids, a catalytic oxidation reaction of olefins (Wacker method), oxidation of secondary alcohols, dehydrogenation and cycloalkanes. It can be easily obtained by oxidation of. In the case of the Wacker method, the obtained ketone can be separated and purified into a single product by precision distillation. Further, the aldehyde represented by the general formula (III) used in the present invention can be easily prepared by, for example, dehydrogenation reaction of fatty alcohol, hydroformylation reaction of olefin (oxo method), Rosemund reduction of fatty acid chloride or direct hydrogenation of fatty acid. Can be obtained. In the case of the oxo method, a linear product and a branched product are produced, but they can be separated and purified into a single product by precision distillation.

As the reactive derivative of the carbonyl compound used in the present invention, there are ketals and acetals which are easily synthesized from the above-mentioned ketones, aldehydes and lower alcohols having 1 to 6 carbon atoms by an acid catalyst. Specific examples of the lower alcohol having 1 to 6 carbon atoms include methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, tert-butanol, amyl alcohol, isoamyl alcohol,
Neopentyl alcohol, 1-methylbutanol, 1,1-dimethylpropanol, 1-ethylpropanol, hexanol, isohexanol, 2-ethylbutanol, 1-methylamyl alcohol, 1,3-dimethylbutanol, 1-ethylbutanol, etc. can give.

The cyclic ketal and cyclic acetal used in the lubricating oil composition of the present invention can be obtained as follows. The reaction between the polyhydric alcohol and the ketone is a ketalization reaction, and this reaction uses an acid catalyst such as p-toluenesulfonic acid, methanesulfonic acid, or sulfuric acid as a catalyst in an amount of 0.05 to 10 mol% with respect to the polyhydric alcohol. Preferably 0.1-7.0 mol%, more preferably 0.5-
It is carried out using 5.0 mol%. This reaction is solvent-free, or xylene, toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane, pentane,
The water formed is removed in an inert solvent such as ligroin or petroleum ether, or in a mixed solution thereof at a temperature of 40 to 160 ° C, preferably 60 to 100 ° C, depending on the boiling point of the ketone used. It is preferable to do so. In some cases, it is also effective to carry out the reaction under reduced pressure. If the temperature is lower than this, the reaction does not proceed, and if the temperature is higher than this, coloring is severe and side reactions occur, which is not preferable. Further, under a nitrogen flow condition, either under a nitrogen atmosphere or under a dry air atmosphere may be used. The reaction time may vary depending on various conditions, but is usually 5 to 200.
Time is preferred. The obtained cyclic ketal is neutralized, then subjected to pretreatment such as filtration and washing, and then treated with clay.
It can be purified by operations such as crystallization and distillation.

The reaction between the polyhydric alcohol and the aldehyde is an acetalization reaction, and this reaction uses an acid catalyst such as p-toluenesulfonic acid, methanesulfonic acid, or sulfuric acid as a catalyst with respect to the polyhydric alcohol of 0.01. ˜5.0 mol%, preferably 0.05 to 3.0 mol%, more preferably 0.1 to 2.0 mol%. This reaction is carried out without solvent or in an inert solvent such as xylene, toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane, pentane, ligroin, petroleum ether, etc., or in a mixed solution thereof, to the boiling point of the aldehyde used. 20 to 130 ° C., preferably 4
It is preferable to carry out at a temperature of 0 to 100 ° C. while removing the produced water. In some cases, it is also effective to carry out the reaction under reduced pressure. If the temperature is lower than this, the reaction will not proceed,
If it is too high, coloring is severe and side reactions occur, which is not preferable. Further, under a nitrogen flow condition, either under a nitrogen atmosphere or under a dry air atmosphere may be used. The reaction time may vary depending on various conditions, but is usually preferably 1 to 30 hours. The obtained cyclic acetal can be purified by neutralization, pretreatment such as filtration and washing, and subsequent operations such as clay treatment, crystallization and distillation.

The reaction between the polyhydric alcohol and the ketal, which is a reactive derivative of a ketone, is a transketalization reaction, and this reaction uses many acid catalysts such as paratoluenesulfonic acid, methanesulfonic acid and sulfuric acid as a catalyst. 0.05 to 10 mol%, preferably 0.1 to 10
The amount is 7.0 mol%, and more preferably 0.5 to 5.0 mol%. This reaction is solvent-free, or xylene, toluene, benzene, octane, isooctane, heptane,
In an inert solvent such as hexane, cyclohexane, pentane, ligroin or petroleum ether, or in a mixed solution thereof, depending on the boiling points of the ketal used and the lower alcohol produced, 40 to 160 ° C., preferably 60 to 160 ° C.
It is preferable to carry out at a temperature of 130 ° C. while removing the produced lower alcohol. In some cases, it is also effective to carry out the reaction under reduced pressure. If the temperature is lower than this, the reaction does not proceed, and if the temperature is higher than this, coloring is severe and side reactions occur, which is not preferable. Further, under a nitrogen flow condition, either under a nitrogen atmosphere or under a dry air atmosphere may be used. The reaction time may vary depending on various conditions, but is usually preferably 5 to 200 hours. The obtained cyclic ketal can be purified by neutralization, pretreatment such as filtration and washing, and then operations such as clay treatment, crystallization and distillation.

The reaction between polyhydric alcohol and acetal which is a reactive derivative of aldehyde is a transacetalization reaction, and this reaction is carried out by using an acid catalyst such as paratoluenesulfonic acid, methanesulfonic acid or sulfuric acid as a catalyst. 0.01-5.0 mol%, preferably 0.05-3.0 mol%, more preferably 0.1-5.0 mol% with respect to alcohol
It is carried out using 2.0 mol%. This reaction is solvent-free, or xylene, toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane, pentane,
In an inert solvent such as ligroin or petroleum ether, or in a mixed solution thereof, depending on the boiling points of the acetal used and the lower alcohol produced, 20 to 130 ° C,
It is preferably carried out at a temperature of 40 to 100 ° C. while removing the produced lower alcohol. In some cases, it is also effective to carry out the reaction under reduced pressure. If the temperature is lower than this, the reaction does not proceed, and if the temperature is higher than this, coloring is severe and side reactions occur, which is not preferable. Further, under a nitrogen flow condition, either under a nitrogen atmosphere or under a dry air atmosphere may be used. The reaction time may vary depending on various conditions, but is usually preferably 1 to 30 hours. The obtained cyclic acetal is neutralized, then subjected to pretreatment such as filtration and washing, and then treated with clay, crystallization,
It can be purified by an operation such as distillation.

The ratio of a ketone or a ketal which is a reactive derivative of a ketone or an aldehyde or an acetal (hereinafter abbreviated as a carbonyl compound) which is a reactive derivative of an aldehyde to be reacted with a polyhydric alcohol is 1 mole of the polyhydric alcohol. , Carbonyl compound A / 2 mol (A is the valence of the polyhydric alcohol). In order to accelerate the reaction rate, it is also effective to carry out the reaction using an excess of carbonyl compound over A / 2 mol and remove the excess carbonyl compound after completion of the reaction.

The cyclic ketal or cyclic acetal used in the present invention is one or more polyhydric alcohols and one or more ketones or ketals which are reactive derivatives of ketones or acetals which are aldehydes or reactive derivatives of aldehydes. Can be obtained by reacting.
Further, the cyclic ketal or cyclic acetal obtained here can be mixed and used. For example, a cyclic ketal obtained from 1 mol of sorbitol and 3 mol of methyl ethyl ketone (40 ° C viscosity 63.1 mm ² / s) and a cyclic ketal obtained from 1 mol of diglycerin and 2 mol of methyl ethyl ketone (40 ° C viscosity 7.69 mm ² / s) Can be individually synthesized and mixed to adjust the viscosity to a desired value. As a specific example, 1 mol of a cyclic ketal obtained from 1 mol of sorbitol and 3 mol of methyl ethyl ketone and 1 mol of a cyclic ketal obtained from 1 mol of diglycerin and 2 mol of methyl ethyl ketone can be mixed to obtain a lubricating oil of VG22. it can. Alternatively, 1 mol of sorbitol, 1 mol of diglycerin and 5 mol of methyl ethyl ketone can be reacted to obtain the above mixture. Also, 1 mol of sorbitol and two kinds of ketones and aldehydes, for example,
The cyclic ketal or cyclic acetal used in the present invention can also be obtained by reacting 2,5,5-trimethylhexanal (2 mol) and methyl ethyl ketone (1 mol).

The less unreacted hydroxyl groups in the cyclic ketal or cyclic acetal, the more preferable it is 10% or less, preferably 5% or less, more preferably 3% or less, particularly preferably 2% or less, most preferably 1% or less. is there. If more than 10% of unreacted hydroxyl groups remain, the compatibility with hydrofluorocarbons and the electrical insulation are poor, which is not preferable.

Further, the cyclic ketal or cyclic acetal used in the present invention preferably has a structure in which the polyhydric alcohol as a raw material does not have an ether bond because the electric insulation is high. Therefore, as described above, sorbitol, mannitol, galactitol, iditol, talitol,
The cyclic ketal or cyclic acetal obtained from a hexavalent alcohol such as allitol or a polyhydric alcohol such as erythritol is better to use a cyclic ketal or cyclic obtained from an alcohol having one ether bond such as diglycerin or ditrimethylolpropane. It is more preferable to use acetal.

Further, the cyclic ketal or cyclic acetal to be used is preferably one containing a 1,3-dioxolane structure and / or a 1,3-dioxane structure in order to enhance electric insulation.
Of these, those containing a 1,3-dioxolane structure are particularly preferable. Therefore, it is preferable to use an alcohol having a hydroxyl group at the adjacent position such as erythritol, diglycerin, sorbitol, mannitol, galactitol, iditol, talitol, and allitol. Further, when a hexahydric alcohol such as sorbitol, mannitol, galactitol, iditol, taritol, and allitol is used, the cyclic ketals and cyclic acetals represented by the formulas IVa and IVb can be obtained, but three 1,3-dioxolane structures are obtained. Formula IVa is preferable because it has higher electric insulation.
Further, when erythritol is used, the cyclic ketals and cyclic acetals represented by the formulas Va and Vb can be obtained.
Formula Va having a 1,3-dioxolane structure is preferable because it has higher electric insulation. Hexahydric alcohols such as sorbitol, mannitol, galactitol, iditol, taritol, and allitol, and erythritol are likely to form a cyclic ketal of the formula IVa and formula Va when reacted with a ketone or a ketal, and a formula IVb when reacted with an aldehyde or an acetal. , The cyclic acetal of the formula Vb is easily generated. Therefore, for these alcohols,
It is preferable to react with a ketone or a ketal.

[0052]

[Chemical 10]

The cyclic ketal or cyclic acetal used in the present invention is a cyclic ketal or cyclic acetal of a hexavalent alcohol represented by the formula (IV) among the polyhydric alcohols having an even number of valences, and the formulas (V) to (). Cyclic ketals and cyclic acetals obtained from tetrahydric alcohols such as erythritol, diglycerin, and ditrimethylolpropane shown in VII) balance various physical properties such as compatibility with hydrofluorocarbons, electrical insulation, melting point, and viscosity. It is particularly preferable from the point of view. Even with the same tetrahydric alcohol, the cyclic ketals obtained from pentaerythritol having good symmetry represented by the formula (VIIIa) or (VIIIb) both become solid at room temperature, which is not preferable. Among the compounds represented by the formulas (IV) to (VII), the compound has a 1,3-dioxolane structure (IV
a), (IVb), (Va), and (VI) are preferable, and among them, compounds (IVa), (Va), and (VI) having only a 1,3-dioxolane structure are particularly preferable. The polyhydric alcohol has no ether bond (IV
The compounds shown in a) and (Va) are preferred.

[0054]

[Chemical 11]

[0055]

[Chemical 12]

The melting point of the cyclic ketal or cyclic acetal used in the present invention is preferably 10 ° C or lower, more preferably -10 ° C or lower, and particularly preferably -30 ° C or lower. The cyclic ketal or cyclic acetal having a melting point of more than 10 ° C. such as (VIIIa) or (VIIIb) is mixed with another cyclic ketal or cyclic acetal used in the present invention having a low melting point, or other lubricating oil, and the addition amount is Can be used by limiting

[0057] cyclic ketal or cyclic acetals used in the present invention, 100 viscosity ℃ is 1 mm ² / s or more 100 mm ² /
s or less, more preferably 1 mm ² / s or more and 50
mm ² / s or less, particularly preferably 1 mm ² / s or more and 30 mm ² / s or less.

The cyclic ketal or cyclic acetal used in the present invention preferably has a low two-layer separation temperature from hydrofluorocarbon, and is preferably 10 ° C. or lower, preferably 0 ° C.
The temperature is preferably below -10 ° C, more preferably below -30 ° C, particularly preferably below -30 ° C. However, even if a cyclic ketal or a cyclic acetal having a two-layer separation temperature of more than 10 ° C. with a hydrofluorocarbon, the two-layer separation temperature of another cyclic ketal or a cyclic acetal to be mixed or a hydrofluorocarbon of another lubricating oil is low. When the temperature of the mixture is 10 ° C. or lower, a cyclic ketal or a cyclic acetal having a two-layer separation temperature with hydrofluorocarbon of more than 10 ° C. can be used in the composition for a working fluid of a refrigerator.

The phosphorus compound (B) used in the present invention is represented by the general formula (I) and / or (II).

[0060]

[Chemical 13]

In the above formula (I), X ₁ , X ₂ and X ₃ represent a linear or branched alkylene group having 2 to 4 carbon atoms, and p, q
And r represent 0 to 30. X ₄ , X ₅ and X ₆ may be the same or different and are a linear alkyl group having 1 to 18 carbon atoms, a branched chain alkyl group having 3 to 18 carbon atoms, or 2 to 2 carbon atoms. A straight chain alkenyl group having 18 carbon atoms, a branched chain alkenyl group having 3 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, an aralkyl group having 7 to 18 carbon atoms, and a halogenated alkyl group having 1 to 18 carbon atoms Represents a group or a halogenated aryl group having 6 to 18 carbon atoms.

In the above formula (II), X ₇ and X ₈ have 2 carbon atoms.
4 represents a linear or branched alkylene group, and s and t are 0.
Represents ~ 30. X ₉ , X ₁₀ and X ₁₁ may be the same or different and are a straight chain alkyl group having 1 to 18 carbon atoms, a branched chain alkyl group having 3 to 18 carbon atoms,
Linear alkenyl group having 2 to 18 carbon atoms, 3 to 3 carbon atoms
A branched alkenyl group having 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, an aralkyl group having 7 to 18 carbon atoms, a halogenated alkyl group having 1 to 18 carbon atoms, or a halogenated group having 6 to 18 carbon atoms Represents an aryl group.

A straight-chain or branched-chain alkyl group, a straight-chain or branched-chain alkenyl group, an aryl group, an aralkyl group, a halogenated alkyl group represented by X ₄ , X ₅ , X ₆ , X ₉ , X ₁₀ and X ₁₁ or If the aryl halide group has more than 18 carbon atoms, the compatibility with the hydrofluorocarbon-based refrigerant becomes poor.

Examples of the linear alkyl group having 1 to 18 carbon atoms include methyl group, ethyl group, propyl group, butyl group,
Examples thereof include a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl group and an octadecyl group.

Examples of the branched chain alkyl group having 3 to 18 carbon atoms include isopropyl group, cyclopropyl group, 1-methylpropyl group, 2-methylpropyl group, t-butyl group, 1-methylbutyl group and 2-methylbutyl group. , 3-methylbutyl group, 1-ethylpropyl group, 1,1-dimethylpropyl group, 1,2-dimethylpropyl group, 2,2-
Dimethylpropyl group, cyclopentyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, 1-ethylbutyl group, 2-
Ethylbutyl group, 1,2-dimethylbutyl group, 1,3-
Dimethylbutyl group, 2,3-dimethylbutyl group, 1,1
-Dimethylbutyl group, 2,2-dimethylbutyl group, 3,
3-dimethylbutyl group, 1-ethyl-2-methylpropyl group, 1-ethyl-1-methylpropyl group, 1,1,2
-Trimethylpropyl group, 1,2,2-trimethylpropyl group, cyclohexyl group, cyclopentylmethyl group,
Methylcyclopentyl group, 1-methylhexyl group, 2-
Methylhexyl group, 3-methylhexyl group, 4-methylhexyl group, 5-methylhexyl group, 1-ethylpentyl group, 2-ethylpentyl group, 2,4-dimethylpentyl group, 3,4-dimethylpentyl group, 1,1-dimethylpentyl group, 1,4-dimethylpentyl group, 1-propylbutyl group, 1-isopropylbutyl group, 1,3,3-
Trimethylbutyl group, 1,1-diethylpropyl group,
2,3-dimethyl-1-ethylpropyl group, 1,2-dimethyl-1-ethylpropyl group, 1-isopropyl-2
-Methylpropyl group, cycloheptyl group, cyclohexylmethyl group, methylcyclohexyl group, 1-methylheptyl group, 2-methylheptyl group, 1-ethylhexyl group, 2-ethylhexyl group, 1,1,3,3-tetramethylbutyl Group, 1,1-diisopropylethyl group, 1-
Ethyl-1,2,2-trimethylpropyl group, 1,5-
Dimethylhexyl group, 3,5-dimethylhexyl group, 2
-Propylpentyl group, 2,4,4-trimethylpentyl group, 1-ethyl-2-methylpentyl group, 2,2-dimethylhexyl group, 1,1-dimethylhexyl group, cycloheptylmethyl group, dimethylcyclohexyl group, 4-
Methylcyclohexylmethyl group, cyclooctyl group, 1
-Cyclohexylethyl group, 2-cyclohexylethyl group, ethylcyclohexyl group, 1-methyloctyl group,
5-methyloctyl group, 1- (2'-methylpropyl)
-3-methylbutyl group, 1,1-diethyl-2,2-dimethylpropyl group, 3,5,5-trimethylhexyl group, 3-cyclohexylpropyl group, 1,1-dimethylheptyl group, 1-methylnonyl group, 1 -Propylheptyl group, 3,7-dimethyloctyl group, 2,4,6-trimethylheptyl group, 4-cyclohexylbutyl group, butylcyclohexyl group, 3,3,5,5-tetramethylcyclohexyl group, 1-methyldecyl group , 2-methyldecyl group, 2-ethylnonyl group, 1-methylundecyl group,
2-methylundecyl group, 2-ethyldecyl group, 1-
(2'-methylpropyl) -3,5-dimethylhexyl group, 2,4,6,8-tetramethylnonyl group, 2-methyldodecyl group, 2-ethylundecyl group, 1- (3'-
Methylbutyl) -6-methylheptyl group, 1- (1'-
Methylbutyl) -4-methylheptyl group, tetradecyl group, 1-methyltridecyl group, 2-methyltridecyl group, 2-ethyldodecyl group, 2- (3'-methylbutyl) -7-methyloctyl group, 2- ( 1'-methylbutyl) -5-methyloctyl group, 1-hexylnonyl group,
2-methyltetradecyl group, 2-ethyltridecyl group,
1-methylpentadecyl group, 1- (1 ', 3', 3'-
Trimethylbutyl) -4,6,6-trimethylheptyl group, 1- (3'-methylhexyl) -6-methylnonyl group, 2-heptylundecyl group, 2- (1 ', 3',
3'-trimethylbutyl) -5,7 ', 7'-trimethyloctyl group, 2- (3'-methylhexyl) -7-methyldecyl group and the like can be mentioned.

Examples of the linear alkenyl group having 2 to 18 carbon atoms include propenyl group, 2-decenyl group, 9-decenyl group, 9-undecenyl group, 10-undecenyl group and 2
-Dodecenyl group, 3-dodecenyl group, 2-tridecenyl group, 4-tetradecenyl group, 9-tetradecenyl group, 9
-Pentadecenyl group, 9-hexadecenyl group, 9-heptadecenyl group, 9-octadecenyl group and the like.

Examples of the branched chain alkenyl group having 3 to 18 carbon atoms include isopropenyl group, 3-methyl-2-nonenyl group, 2,4-dimethyl-2-decenyl group, 2-methyl-9-heptadecenyl group and the like. Is mentioned.

Examples of the aryl group having 6 to 18 carbon atoms include phenyl group, 2- or 3- or 4-methylphenyl group, 2- or 3- or 4-ethylphenyl group, 2- and 3-.
-Or 2-, 4- or 2-, 5- or 2-, 6- or 3
-, 4- or 3-, 5-dimethylphenyl group, 2- or 3- or 4-isopropylphenyl group, 2- or 3- or 4-propylphenyl group, 2-, 3-, 5- or 2
-, 3-, 6- or 3-, 4-, 5-trimethylphenyl group, 2- or 3- or 4-t-butylphenyl group, 2
-Or 3- or 4-sec-butylphenyl group, 4- or 5-isopropyl-3-methylphenyl group, 4-t-
Amylphenyl group, 3- or 4- or 5-methyl-2-
t-butylphenyl group, pentamethylphenyl group, naphthyl group, 2-methylnaphthyl group, 2,6-diisopropylphenyl group, 4-t-octylphenyl group, 2, -4
-Or 2-, 6- or 3-, 5-di-t-butylphenyl group, di-sec-butylphenyl group, 2-, 6-di-
Examples thereof include t-butyl-4-methylphenyl group, 2,4,6-tri-t-butylphenyl group and 4-nonylphenyl group.

Examples of the aralkyl group having 7 to 18 carbon atoms include benzyl group, 2- or 3- or 4-methylbenzyl group, phenethyl group, sec-phenethyl group, 2, and 4
-Or 2-, 5- or 3-, 4- or 3-, 5-dimethylbenzyl group, 4-ethylbenzyl group, 2- or 3- or 4-methylphenethyl group, α- or β-methylphenethyl group, α-, α-dimethylbenzyl group, 1- or 3-
Phenylpropyl group, α- or β-ethylphenethyl group, 4-isopropylbenzyl group, α-isopropylbenzyl group, α-, α-dimethylphenethyl group, 1- or 3- or 4-phenylbutyl group, α-ethyl, α-methylbenzyl group, 4-butylbenzyl group, 4-t-butylbenzyl group, 1,1-dimethyl-3-phenylpropyl group, 1- or 3-phenyl-2,2-dimethylpropyl group, α-propyl Examples thereof include a phenethyl group, a 5-phenylpentyl group, a naphthylmethyl group, a naphthylethyl group and a 6-phenylhexyl group.

The halogen atom of the halogenated alkyl group having 1 to 18 carbon atoms includes fluorine, chlorine, bromine,
Although iodine and the like can be mentioned, chlorine is preferable. Specific examples thereof include β-chloroethyl group and 2,3 dichloropropyl group.

The halogen atom of the halogenated aryl group having 6 to 18 carbon atoms includes fluorine, chlorine, bromine,
Although iodine and the like can be mentioned, chlorine is preferable. Specific examples include a 2-, 3- or 4-monochlorophenyl group, a dichlorophenyl group, a monochloro-4-methylphenyl group,
A dichloro-4-methylphenyl group etc. are mentioned.

X ₁ , X ₂ , X ₃ , X ₇ and X ₈ represent a linear or branched alkylene group having 2 to 4 carbon atoms. When the carbon number exceeds 4, the compatibility with hydrofluorocarbon deteriorates. Examples of the linear or branched alkylene group having 2 to 4 carbon atoms include ethylene group, propylene group, trimethylene group, butylene group, isobutylene group and tetramethylene group.

Of the phosphorus compounds represented by the above (I),
The phosphorus compound having a straight chain or branched chain alkyl group, a straight chain or branched chain alkenyl group, an aralkyl group and an aryl group includes a straight chain or branched chain alkyl alcohol, a straight chain or branched chain alkenyl alcohol, an aralkyl alcohol and an aryl alcohol and an anhydride. It can be obtained by a reaction with phosphoric acid (P ₂ O ₅ ) or the like. At this time, when the reaction is carried out in the presence of water, orthophosphoric acid or polyphosphoric acid, it can be obtained in a high yield.
The halogenated alkyl group and halogenated aryl group can be obtained by, for example, substituting a halogen for the hydrogen of the alkyl group or aryl group of the corresponding phosphorus compound. The phosphorus compound containing a linear or branched oxyalkylene group can be obtained by an esterification reaction with oxyalkylene glycol, an alkylene oxide addition reaction, or the like. The phosphonate ester represented by the above (II) can be produced by an already known ordinary method. For example, when di-2-ethylhexyl 2-ethylhexyl phosphonate is taken as an example, it can be obtained by reacting tri-2-ethylhexyl phosphite with 2-ethylhexyl bromide.

The compounding amount of the phosphorus compound (I) and / or (II) is at least an amount sufficient to suppress abrasion while the lubricating oil composition of the present invention is in contact with the metal surface. That is, cyclic ketal or cyclic acetal 100
The blending amount of the phosphorus compound (I) and / or (II) is preferably 0.01 to 5.0 parts by weight with respect to parts by weight. More preferably 0.1 to 3.0 parts by weight, particularly preferably 0.1.
1 to 2.0 parts by weight. If less than 0.01 parts by weight,
When the wear-suppressing effect is poor and the amount exceeds 5.0 parts by weight, the compatibility with hydrofluorocarbon becomes poor and the volume resistivity which is a required characteristic of refrigerating machine oil becomes poor. In the present invention, by using the phosphorus compound as described above, the adsorption activity of phosphorus atoms to the metal is enhanced, so that the wear suppressing effect can be obtained, and further, the seizure resistance and other effects can be obtained.

The melting point of the lubricating oil composition of the present invention is 10
C. or less is preferable, -10.degree. C. or less is more preferable, and -30.degree. C. or less is particularly preferable. The lubricating oil composition of the present invention desirably has a low two-layer separation temperature from hydrofluorocarbon, and is 10 ° C. or less, preferably 0 ° C.
The temperature is preferably below -10 ° C, more preferably below -30 ° C, particularly preferably below -30 ° C.

The lubricating oil composition of the present invention has a temperature of 100 ° C.
The viscosity is preferably 1 mm ² / s or more and 100 mm ² / s or less, more preferably 1 mm ² / s or more and 50 mm ² / s or less, and particularly preferably 1 mm ² / s or more and 30 mm ² / s or less.

The acid value (mgKOH of the lubricating oil composition in the present invention
/ g) is 5 or less, preferably 1 or less, more preferably 0.5 or less, and particularly preferably 0.1 or less. When the acid value exceeds 5, not only the hydrolysis of the phosphorus compound is promoted but also the thermal oxidation stability of the lubricating oil composition itself is impaired,
Further, it is not preferable because it causes corrosion of the metal material, lowering of flash point, offensive odor, lowering of electric insulation and the like.

Further, the hydroxyl value (mgKOH / g) of the lubricating oil composition of the present invention is 50 or less, preferably 20 or less, more preferably 10 or less, and particularly preferably 5 or less. When the hydroxyl value exceeds 50, it is not preferable because the obtained lubricating oil composition causes a decrease in the flash point and a decrease in the electric insulation.

The lubricating oil composition of the present invention can be used as a mixture with another lubricating oil. Other lubricating oils include mineral oils, polybutenes, poly-α-olefins, hydrocarbon synthetic oils such as alkylbenzenes, aliphatic diesters, neopentyl polyol esters, polyalkylene glycols,
Examples include polyphenyl ethers, carbonates, silicate esters, silicone oils, perfluoropolyethers, etc. Specific examples are given in the new edition of physics of lubrication (Koushobo) and basics and applications of lubricating oils (Corona). ing.

When the lubricating oil composition of the present invention is mixed with another lubricating oil, the mixing ratio is 50% by weight, preferably 70% by weight of the lubricating oil composition of the present invention in the mixed lubricating oil.
It is desirable that the content is at least 90% by weight, more preferably at least 90% by weight. When the content of the lubricating oil composition in the present invention is less than 50% by weight, the effect of the lubricating oil composition in the present invention cannot be sufficiently exhibited.

The other lubricating oil to be mixed is preferably one having excellent compatibility with hydrofluorocarbon, and neopentyl polyol ester, polyalkylene glycol, perfluoropolyether, carbonate, perfluoroester and the like are preferable. However, when the compatibility of the lubricating oil composition of the present invention with hydrofluorocarbon is sufficiently excellent, for example, the two-layer separation temperature is -30 ° C.
Hereafter, when the temperature is preferably -50 ° C or lower, a lubricating oil having poor compatibility with hydrofluorocarbon, such as alkylbenzene or mineral oil, can be mixed within a range in which the two-layer separation temperature does not exceed 10 ° C.

The mixing ratio of the hydrofluorocarbon and the lubricating oil composition in the refrigerator working fluid composition of the present invention is
Normal hydrofluorocarbon / lubricant composition = 50 /
It is 1 to 1/20 (weight ratio). Preferably 10/1
~ 1/5 (weight ratio). When the ratio of hydrofluorocarbon is higher than that of hydrofluorocarbon / lubricating oil composition = 50/1, the viscosity of the hydrofluorocarbon / lubricating oil composition mixed solution may be low and the lubricity may be deteriorated, which is not preferable. Further, if the ratio of hydrofluorocarbon is lower than 1/20 of hydrofluorocarbon / lubricating oil composition, the refrigerating capacity may be insufficient, which is not preferable.

The hydrofluorocarbon used here is, for example, difluoromethane (HFC32),
1,1-difluoroethane (HFC152a), 1,
1,1-trifluoroethane (HFC143a), 1,
1,1,2-Tetrafluoroethane (HFC134
a), 1, 1, 2, 2-tetrafluoroethane (HFC
134), pentafluoroethane (HFC125), etc., particularly 1, 1, 1, 2-tetrafluoroethane, difluoromethane, pentafluoroethane, 1, 1, 1-
Trifluoroethane is preferred. These hydrofluorocarbons may be used alone, or two or more kinds of hydrofluorocarbons may be mixed and used.

If desired, the additive for a working fluid for a refrigerator of the present invention may contain various additional additives which are usually used. The refrigerator working fluid composition of the present invention itself has no problem even if water coexists, but it is an insulating material PET.
A film or the like may be hydrolyzed to form a PET oligomer, which may clog a capillary tube or the like. Therefore, it is desirable to add an additive for removing water to the composition for refrigerator working fluid of the present invention. Additives for removing water include compounds having an epoxy group, orthoesters, acetals (ketals), carbodiimides and the like.

The compound having an epoxy group has 4 to 60 carbon atoms, preferably 5 to 25 carbon atoms.
Specifically, phenyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, cresyl glycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol glycidyl ether, glycerin triglycidyl ether, trimethylolproban triglycidyl ether. ,
Glycidyl ethers such as pentaerythritol triglycidyl ether, glycidyl esters such as phthalic acid glycidyl ester, cyclohexanedicarboxylic acid glycidyl ester, adipic acid glycidyl ester, 2-ethylhexanoic acid glycidyl ester, epoxidized methyl stearate, epoxidized Epoxidized fatty acid monoesters such as butyl stearate, epoxidized soybean oil, epoxidized vegetable oils such as epoxidized linseed oil, epoxy cyclooctane, epoxy cycloheptane, compounds having an epoxy cyclohexyl group, compounds having an epoxy cyclopentyl group Alicyclic epoxy compounds such as Among these compounds having an epoxy group, a compound having an epoxycyclohexyl group and a compound having an epoxycyclopentyl group are particularly excellent.

The compound having an epoxycyclohexyl group and the compound having an epoxycyclopentyl group used in the present invention have 5 to 40 carbon atoms, preferably 5 to 2 carbon atoms.
5 of them. Specifically, JP-A-5-209171,
It is described in columns 11, lines 34 to 46. Although not particularly limited, preferably 1,2-epoxycyclohexane, 1,2-epoxycyclopentane,
Bis (3,4-epoxycyclohexylmethyl) adipate, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 2- (7- Oxabicyclo [4.1.0] hept-
3-yl) -spiro (1,3-dioxane-5,3 ′
[7] Oxabicyclo [4.1.0] heptane).

In the present invention, these epoxy group-containing compounds may be used alone or in combination of two or more kinds. The addition amount is usually 0.05 to 5 parts by weight with respect to 100 parts by weight of a base oil containing a cyclic ketal or a cyclic acetal as a main component.
The amount is 2.0 parts by weight, preferably 0.1 to 1.5 parts by weight, and more preferably 0.1 to 1.0 parts by weight.

The orthoester used in the present invention has 4 to 70 carbon atoms, more preferably 4 carbon atoms.
~ 50. Specifically, JP-A-6-1707
3, column 10, lines 27-41.
The orthoester is added in an amount of 100 parts by weight of a base oil containing a cyclic ketal or a cyclic acetal as a main component.
Usually 0.01 to 100 parts by weight, preferably 0.05 to 3
0 parts by weight.

The acetal or ketal used in the present invention has 4 to 70 carbon atoms, and more preferably 4 to 50 carbon atoms. Specifically, Japanese Patent Laid-Open No. 6-1
7073, columns 11, 21. The amount of acetal or ketal added is usually 0.01 to 100 parts by weight, preferably 0.0 to 100 parts by weight of a base oil containing a cyclic ketal or a cyclic acetal as a main component.
5 to 30 parts by weight.

The carbodiimide used in the present invention is represented by the following formula (IX). R ₅ —N═C═N—R ₆ (IX) In the formula, R ₅ and R ₆ represent a hydrocarbon group having 1 to 18 carbon atoms, more preferably 1 to 12 carbon atoms. R
₅ and R ₆ may be the same or different. R ₅ and R
Specific examples of ₆ include the same as those listed for X ₄ , X ₅ , X ₆ , X ₉ , X ₁₀ and X ₁₁ . As a specific example, 1,3-diisopropylcarbodiimide,
1,3-di-t-butyl-carbodiimide, 1,3-dicyclohexylcarbodiimide, 1,3-di-p-tolylcarbodiimide, 1,3-bis- (2,6-diisopropylphenyl) carbodiimide and the like. Preferably, 1,3-diisopropylcarbodiimide, 1,3-
Di-p-tolyl carbodiimide, 1,3-bis- (2,
6-diisopropylphenyl) carbodiimide.

Here, the amount of carbodiimide added is 100 base oil containing a cyclic ketal or cyclic acetal as a main component.
The amount is usually 0.01 to 10 parts by weight, preferably 0.05 to 5 parts by weight, based on parts by weight.

Further, for the purpose of preventing corrosion of metal by carboxylic acid or the like, benzotriazole and / or benzotriazole derivative for protecting the metal surface is added as an additive, and radical trap for improving thermal stability. It is effective to add a phenolic compound having the ability and a metal deactivator having the chelating ability.

The addition amount of the benzotriazole and / or benzotriazole derivative used in the present invention is such that the base oil containing a cyclic ketal or a cyclic acetal as a main component is 10
The amount is usually 0.001 to 0.1 part by weight, preferably 0.003 to 0.03 part by weight, based on 0 part by weight.
The benzotriazole and benzotriazole derivative used in the present invention have 6 to 50 carbon atoms, preferably 6 to 30 carbon atoms. Specifically, Japanese Patent Laid-Open No. 5-
209171, column 13, lines 9 to 29. Although not particularly limited, benzotriazole, 5-methyl-1H-benzotriazole and the like are preferable.

The amount of the metal deactivator used in the present invention is usually 0.001 to 2.0 with respect to 100 parts by weight of a base oil containing a cyclic ketal or a cyclic acetal as a main component.
Parts by weight, preferably 0.003 to 0.5 parts by weight. The metal deactivator used in the present invention preferably has a chelating ability and has a carbon number of 5 to 50,
It is preferably 5 to 20. Specifically, Japanese Patent Laid-Open No. 5-2
09171, columns 13, 38 to columns 14, 8
It is described in the line. Although not particularly limited, preferably N, N'-disalicylidene-1,2-diaminoethane, N, N'-disalicylidene-1,2-diaminopropane, acetylacetone, acetoacetate, alizarin, quinizarin, etc. is there.

The amount of the phenolic compound having a radical trapping ability used in the present invention is usually 0.05 to 2.0 parts by weight with respect to 100 parts by weight of a base oil containing a cyclic ketal or a cyclic acetal as a main component. And preferably 0.05 to 0.5 parts by weight. The phenolic compound used in the present invention has 6 to 100 carbon atoms, preferably 10 to 80 carbon atoms. Specifically, it is described in JP-A-6-17073, column 12, line 32 to column 13, line 18. Although not particularly limited, preferably 2,6-di-t-butylphenol, 2,6-di-t-butyl-4-methylphenol, 4,4′-methylenebis (2,6-di- t-butylphenol), 4,4'-butylidene bis (3-methyl-6-t
-Butylphenol), 2,2'-methylenebis (4-ethyl-6-t-butylphenol), 2,2'-methylenebis (4-methyl-6-t-butylphenol), 4,4'-isopropylidenebisphenol, 2 , 4-Dimethyl-6-
t-butylphenol, tetrakis [methylene-3-
(3,5-Di-t-butyl-4-hydroxyphenyl) propionate] methane, 1,1,3-tris (2-methyl-
4-hydroxy-5-t-butylphenyl) butane, 1,
3,5-Trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, 2,6-di-
t-Butyl-4-ethylphenol, 2,6-bis (2'-
Hydroxy-3'-t-butyl-5'-methylbenzyl)-
4-methylphenol, bis [2- (2-hydroxy-
5-methyl-3-t-butylbenzyl) -4-methyl-
6-t-butylphenyl] terephthalate, triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6
-Hexanediol-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] and the like.

In addition, various additional additives usually used can be used as required. Lubricating oil additives such as antioxidants, extreme pressure agents, oiliness improvers, defoamers, detergent dispersants, viscosity index improvers, rust preventives and demulsifiers can be added to these. For example, as antioxidants, in addition to the above-mentioned phenolic antioxidants, p, p-dioctylphenylamine, monooctyldiphenylamine, phenothiazine, 3,7-dioctylphenothiazine, phenyl-1-naphthylamine, phenyl-2. -Amine-based antioxidants such as naphthylamine, alkylphenyl-1-naphthylamine, and alkylphenyl-2-naphthylamine; sulfur-based antioxidants such as alkyldisulfide, thiodipropionic acid ester and benzothiazole; and zinc dialkyldithiophosphate. , Zinc diaryldithiophosphate and the like. The addition amount is 0.05 to 2.0 parts by weight with respect to 100 parts by weight of a base oil containing a cyclic ketal or a cyclic acetal as a main component.

As the extreme pressure agent and oiliness improver, for example, zinc compounds such as zinc dialkyldithiophosphate and zinc diaryldithiophosphate, thiodipropionate, dialkyl sulfide, dibenzyl sulfide, dialkyl polysulfide, alkyl can be used. Sulfur compounds such as mercaptan, dibenzothiophene and 2,2'-dithiobis (benzothiazole), chlorine compounds such as chlorinated paraffin, molybdenum dithiocarbamate, molybdenum dithiophosphate, molybdenum compounds such as molybdenum disulfide, perfluoroalkyl polyethers and ,
Examples thereof include trifluorinated ethylene chloride polymers, fluorinated compounds such as fluorinated graphite, silicon compounds such as fatty acid-modified silicone, organic molybdenum compounds, molybdenum disulfide, and graphite. The amount added is 0.0 based on 100 parts by weight of a base oil containing a cyclic ketal or a cyclic acetal as a main component.
It is 5 to 10 parts by weight.

As the defoaming agent, silicone oil such as dimethylpolysiloxane and organosilicates such as diethyl silicate are used. The addition amount thereof is 0.0005 to 1 part by weight with respect to 100 parts by weight of a base oil containing a cyclic ketal or a cyclic acetal as a main component.

The detergents and dispersants used are sulfonates, phenates, salicylates, phosphonates, polybutenyl succinimides, polybutenyl succinates and the like. The addition amount is 0.05 to 10 parts by weight with respect to 100 parts by weight of a base oil containing a cyclic ketal or a cyclic acetal as a main component.

Further, an additive such as an organic tin compound or a boron compound which stabilizes the chlorofluorocarbon refrigerant may be added. The amount of addition thereof is 0.001 to 10 parts by weight with respect to 100 parts by weight of a base oil containing a cyclic ketal or a cyclic acetal as a main component.

[0101]

EXAMPLES The present invention will be described in more detail with reference to production examples and examples, but the present invention is not limited to these examples.

Production Example 1 A 3-liter four-necked flask was equipped with a stirrer, a thermometer, a nitrogen blowing tube, and a dehydration tube equipped with a condenser. D-
Sorbitol 336.8 g (1.85 mol), methyl ethyl ketone 800.0 g (11.1 mol), paratoluene sulfonic acid monohydrate 17.6 g (0.092 mo)
1) and 200 ml of hexane were taken in the flask. The reaction was carried out at 69 to 79 ° C. for 8 hours under a nitrogen atmosphere at atmospheric pressure, and water was distilled off. After completion of the reaction, the mixture was cooled to 60 ° C., 19.6 g of sodium carbonate (0.185 mol, twice the equivalent of paratoluenesulfonic acid) was added to neutralize, and the mixture was stirred at 60 ° C. for 3 times.
Stirred for 0 minutes. 200 g of water was added, and the mixture was stirred at 60 ° C. for 30 minutes and left to stand to separate layers. After removing the lower layer, the solution was washed with 200 g of saturated saline, and hexane and excess methyl ethyl ketone were removed under reduced pressure using a rotary evaporator. Further, it was distilled under reduced pressure to obtain cyclic ketal A1 (hydroxyl value 12.9 mgKOH / g, gas chromatography purity 97.3%). And further cyclic ketal A
Part of 1 was purified by column chromatography,
A cyclic ketal A2 (hydroxyl value 4.6 mg KOH / g, gas chromatography purity 99.1%) was obtained.

Production Example 2 A 3-liter four-necked flask was equipped with a stirrer, a thermometer, a calcium chloride tube, and a dehydration tube equipped with a condenser. D
-Sorbitol 450.0 g (2.47 mol), isobutyraldehyde 588.0 g (8.15 mol), paratoluenesulfonic acid monohydrate 4.7 g (0.025 m)
ol) and petroleum ether 400 having a boiling point of 30 to 60 ° C.
ml was taken in the flask. The reaction was carried out at 40 to 65 ° C. for 15 hours under a dry air atmosphere at atmospheric pressure, and water was distilled off. After completion of the reaction, it was cooled to 60 ° C. and sodium carbonate 5.24 g
(0.049 mol, twice the equivalent of paratoluenesulfonic acid) was added for neutralization, and the mixture was stirred at 60 ° C. for 30 minutes. Water 1
00 g was added, the mixture was stirred at 60 ° C. for 30 minutes, and allowed to stand to separate layers. After removing the lower layer, the mixture was washed with 100 g of saturated saline, and petroleum ether and excess isobutyraldehyde were removed under reduced pressure using a rotary evaporator. Further, it was distilled under reduced pressure to give cyclic acetal B (hydroxyl value 6.0 m
gKOH / g, gas chromatography purity 99.0
%) Was obtained.

Production Example 3 A 3 liter four-necked flask was equipped with a stirrer, a thermometer, a nitrogen blowing tube, and a dehydration tube equipped with a condenser. Diglycerin 460.7 g (2.28 mol), methyl ethyl ketone 800.0 g (11.1 mol), paratoluene sulfonic acid monohydrate 8.74 g (0.046 mo)
1) and 200 ml of hexane were taken in the flask. The reaction was carried out under a nitrogen atmosphere at atmospheric pressure at 66 to 81 ° C. for 15 hours, and water was distilled off. After completion of the reaction, the mixture was cooled to 60 ° C., neutralized by adding 9.8 g of sodium carbonate (0.092 mol, twice equivalent of paratoluenesulfonic acid), and then at 3 ° C. at 3 ° C.
Stirred for 0 minutes. 200 g of water was added, and the mixture was stirred at 60 ° C. for 30 minutes and left to stand to separate layers. After removing the lower layer, water 20
After washing with 0 g, hexane and excess methyl ethyl ketone were removed under reduced pressure using a rotary evaporator. Further, it was distilled under reduced pressure to give cyclic ketal C (hydroxyl value 1
5.7 mg KOH / g, gas chromatography purity 9
8.7%).

The hydroxyl values of the cyclic ketals and cyclic acetals A1 to C used in the products of the present invention obtained in Production Examples (JIS K-
)) And the ratio of unreacted hydroxyl groups to the number of hydroxyl groups of the starting polyhydric alcohol determined from the hydroxyl value, 40 ° C. and 1
Kinematic viscosity at 00 ° C (JIS K-2283), pour point (JIS K-2283)
-2269) was measured. Table 1 shows the results. The kinematic viscosities (JIS K-2283) and pour points (JIS K-2269) at 40 ° C and 100 ° C of the oils a to e used for comparative products were measured. The results are shown in Table 2.

[0106]

[Table 1]

[0107]

[Table 2]

Example 1 To determine the wear resistance of Products 1-22 of the present invention, ASTM D 2
A Falex test according to 670-81 was performed. A1 to C base oil 1
The V block and the pin were dipped in a lubricating oil composition in which the phosphorus compounds shown in Table 3 were added in an amount of 100 parts by weight, and 1,1,1,2-tetrafluoroethane (HFC134
While blowing a) at 10 liter / hr, the temperature is set to 8
Spin at 0 ° C for 10 minutes with no load, then pre-rotate at 200 lb for 5 minutes, and then run at 300 lb for 60 minutes.
The amount of wear of the block and the pin was examined. Table 3 shows the test results of the base oils A1 to C and b to e containing no phosphorus compound as comparative products. The products of the present invention 1 to 22 showed excellent wear resistance, but the amount of wear of the comparative product was larger than that of the product of the present invention.
It was found that the abrasion resistance was inferior.

[0109]

[Table 3]

Example 2 The invention products 1-22 and the comparative products 9-13, which are compositions of the lubricating oil composition and 1,1,1,2-tetrafluoroethane shown in Table 4, were tested at low temperatures. The compatibility with 1,1,1,2-tetrafluoroethane was investigated by measuring the two-layer separation temperature. The results are shown in Table 4. As is clear from Table 4, the products of the present invention had excellent compatibility at low temperatures.
Further, the addition amount of the phosphorus compound exceeds 5 parts by weight (comparative product 1
0), the compatibility became poor.

[0111]

[Table 4]

Example 3 With respect to the products 1 to 22 of the present invention, a shield tube test was carried out under the following conditions in order to investigate the thermal stability. That is, the water concentration is previously set to 10 ppm or less and the acid value is set to 0.03.
(MgKOH / g) 10g of lubricating oil prepared below, and HFC
134 g of 5 g was placed in a glass tube, and iron, copper, and aluminum were added as a catalyst, and the tube was sealed. After testing at 175 ° C. for 14 days, the appearance of the composition of HFC134a and oil and the presence or absence of deposits were examined. After opening the sealed tube to remove HFC134a, the acid value of the oil was examined. The results are shown in Table 5. As is apparent from Table 5, all the products of the present invention have a good appearance,
There was no precipitate and the acid value did not increase, and the thermal stability was good.

[0113]

[Table 5]

Example 4 Inventive products 1 to 22 and comparative products 11 to 1 used in Example 2
For 3, the shield tube test was conducted under the following conditions in order to investigate the thermal stability in the presence of water. That is, the water concentration is 3000 ppm and the acid value is 0.03 in advance.
(MgKOH / g) 10g of lubricating oil prepared below, and HFC
134 g of 5 g was placed in a glass tube, and iron, copper, and aluminum were added as a catalyst, and the tube was sealed. After testing at 175 ° C. for 14 days, the appearance of the composition of HFC134a and oil and the presence or absence of deposits were examined. After opening the sealed tube to remove HFC134a, the acid value of the oil was examined. The results are shown in Table 6. As is clear from Table 6, the products of the present invention have a better appearance, no precipitates, and no increase in the acid value, as compared with the comparative products.
The thermal stability was good.

[0115]

[Table 6]

Example 5 Lubricating oil compositions 1 to 22 used in the present invention shown in Table 7
The electrical insulating properties of the lubricating oil compositions 5, 10 to 13 used for the comparative product were examined. The volume resistivity at 25 ° C was measured based on JIS C-2101. The results are shown in Table 7.
Shown in As is clear from Table 7, the lubricating oil compositions used in the products of the present invention had a high volume resistivity, and all had a better electrical insulation property than the lubricating oil compositions used in the comparative products.

[0117]

[Table 7]

Example 6 The hygroscopic properties of the lubricating oil compositions 1, 3, 7, 8 used in the product of the present invention and the lubricating oil composition 5 used in the comparative product were examined. In a glass tube having an inner diameter of 18 mm and an internal volume of about 10 ml, 2 g of oil prepared in advance with a water concentration of 50 ppm or less is placed,
The sample was placed in a thermostat with a humidity of 80%. After leaving it for a certain period of time, the water concentration of the oil is determined by the Karl Fischer method (JIS K-227).
5) was measured. Table 8 shows the results. As is clear from Table 8, the lubricating oil composition used in the product of the present invention had a very low hygroscopicity and was superior to the lubricating oil composition used in the comparative product.

[0119]

[Table 8]

[0120]

The present invention provides a lubricating oil composition which is excellent in thermal stability and electric insulation, does not generate carboxylic acid due to hydrolysis, has low hygroscopicity, and is inexpensive, and such a lubricating oil composition. The composition for a working fluid of a refrigerator of the present invention containing a hydrofluorocarbon and is capable of reducing the amount of wear on the metal contact surface, has excellent compatibility, thermal stability, electrical insulation, excellent hygroscopicity, and water content. It does not generate carboxylic acid due to decomposition and is inexpensive.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location C10M 137: 12) C10N 30:00 30:12 40:30 (72) Inventor Hiroyasu Togashi Wakayama Minato, Wakayama 1334 Kao Corporation Research Laboratory (72) Inventor Yuichiro Kobayashi Minato Wakayama City 1334 Kao Research Laboratory

Claims (10)

[Claims] 1. A base oil comprising (A) a cyclic ketal or a cyclic acetal as a main component, (B) a general formula (I) and / or (II): (In the formula, X ₁ , X ₂ and X ₃ represent a linear or branched alkylene group having 2 to 4 carbon atoms, p, q and r represent 0 to 30. X ₄ , X ₅ and X ₆ represent They may be the same or different and may be a straight chain alkyl group having 1 to 18 carbon atoms, a branched chain alkyl group having 3 to 18 carbon atoms, a straight chain alkenyl group having 2 to 18 carbon atoms, or a carbon number. A branched alkenyl group having 3 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, an aralkyl group having 7 to 18 carbon atoms, a halogenated alkyl group having 1 to 18 carbon atoms, or 6 to 18 carbon atoms. Represents a halogenated aryl group.
X ₇ and X ₈ represent a linear or branched alkylene group having 2 to 4 carbon atoms, and s and t represent 0 to 30. X ₉ , X ₁₀ and X ₁₁ may be the same or different and are a linear alkyl group having 1 to 18 carbon atoms, a branched chain alkyl group having 3 to 18 carbon atoms, and 2 to 18 carbon atoms. A straight chain alkenyl group having 3 to 18 carbon atoms, a branched chain alkenyl group having 3 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, and 7 to 1 carbon atoms
It represents an aralkyl group having 8, an alkyl halide group having 1 to 18 carbon atoms, or an aryl halide group having 6 to 18 carbon atoms. ) A lubricating oil composition comprising a phosphorus compound represented by the formula (4) and a composition for a working fluid of a refrigerator containing (C) hydrofluorocarbon. 2. To (A) 100 parts by weight of a base oil containing a cyclic ketal or a cyclic acetal as a main component, (B)
The composition for refrigerating machine working fluid according to claim 1, which contains 0.01 to 5 parts by weight of a phosphorus compound. 3. The cyclic ketal or cyclic acetal is one or more polyhydric alcohols having an even valence of 4 or more and 8 or less and a general formula (III): (In the formula, R ₁ represents a hydrogen atom or a linear, branched, or cyclic alkyl group having 1 to 12 carbon atoms, and R ₂ represents 1 carbon atom.
~ 12 straight-chain, branched, or cyclic alkyl groups are shown. Or R ₁ and R ₂ together form a carbon number of 2 to 13
You may form the alkylene group of. However, in either case, the total carbon number of R ₁ and R ₂ is 1 to 13. The composition for a working fluid of a refrigerator according to claim 1, which is a cyclic ketal or a cyclic acetal obtained from at least one kind of a ketal or an acetal which is a carbonyl compound represented by the above) or a reactive derivative thereof. 4. The composition for a refrigerator working fluid according to claim 3, wherein the polyhydric alcohol has no ether bond. 5. The composition for refrigerator working fluid according to claim 3, wherein the polyhydric alcohol has one ether bond. 6. The polyhydric alcohol is a tetravalent or hexavalent saturated aliphatic alcohol having 4 to 25 carbon atoms.
The composition for a working fluid of a refrigerator according to any one of claims. 7. The composition for a working fluid of a refrigerator according to claim 1, wherein the cyclic ketal or the cyclic acetal contains a 1,3-dioxolane structure and / or a 1,3-dioxane structure. 8. The frozen product according to claim 1, wherein the cyclic ketal or cyclic acetal is at least one kind of cyclic ketal or cyclic acetal represented by the formula (IV) or (V). Composition for machine working fluid. Embedded image (In the formula, R ₁ represents a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms, and R ₂ represents 1 to 12 carbon atoms.
12 straight-chain, branched or cyclic alkyl groups are shown. Alternatively, R ₁ and R ₂ may combine to form an alkylene group having 2 to 13 carbon atoms. However, in either case, the total number of carbon atoms of R ₁ and R ₂ bonded to the same carbon atom is 1 to 1
It is 3. ) 9. The frozen product according to claim 1, wherein the cyclic ketal or cyclic acetal is at least one kind of cyclic ketal or cyclic acetal represented by the formula (VI) or (VII). Composition for machine working fluid. [Chemical 4] (In the formula, R ₁ represents a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 12 carbon atoms, and R ₂ represents 1 to 12 carbon atoms.
12 straight-chain, branched or cyclic alkyl groups are shown. Alternatively, R ₁ and R ₂ may combine to form an alkylene group having 2 to 13 carbon atoms. However, in either case, the total number of carbon atoms of R ₁ and R ₂ bonded to the same carbon atom is 1 to 1
It is 3. ) 10. The mixing ratio of hydrofluorocarbon and lubricating oil composition is such that hydrofluorocarbon / lubricating oil composition = 50/1 to 1/20 (weight ratio). A composition for a working fluid of a refrigerator as described above.