JPH0841475A - New refrigeration medium composition - Google Patents

Abstract

PURPOSE:To obtain a new refrigeration medium composition consisting essentially of a lubricating oil comprising a specific fluorine-containing aromatic compound, and a specific fluorine-containing ether-based refrigeration medium and excellent in compatibility and stability, low hygroscopic property and lubricating property. CONSTITUTION:This composition consists essentially of (A) a lubricating oil comprising a fluorine-containing aromatic compound of the formula R(XRf)n [X is O or S; R is a 6-60C n-valent aromatic group; (n) is 1-4; Rf is a 1-25C fluorocarbon group or its partial substituent body and a ratio of F/C in Rf is 0.2 to 3] and (B) a fluorine containing ether-based refrigeration medium having 3-6 sum of number of C and O in the molecule and having H atom in the molecule (e.g. CH2OCH2CF3, CH3OCH2CF3 or CH3CH2OCF2CHF2). Furthermore, when the component A is singly used, a lubricating oil having 2-500cst (especially preferably 10-150cst) dynamic viscosity at 40 deg.C and 0.5-100cst (especially preferably 2-30cst) dynamic viscosity at 100 deg.C is used as the lubricating oil.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a lubricating oil for a fluorine-containing ether type refrigerant.

[0002]

2. Description of the Related Art Conventionally, the refrigerant used in refrigerators for car air conditioners and refrigerators has been mainly CFC-12 (dichlorodifluoromethane). For room air conditioners, HCFC-22 (chlorodifluoromethane)
However, CFC-11 (fluorotrichloromethane) has been mainly used for turbo refrigerators. But,
Chlorofluorocarbon-based refrigerants such as CFC-12 and CFC-11 and hydrochlorofluorocarbon-based refrigerants such as HCFC-22 are said to cause ozone layer depletion, and the development of refrigerants that can replace these is desired. .

Since ozone layer depletion is believed to be due to the action of chlorine atoms contained in chlorofluorocarbons and hydrochlorofluorocarbons, HFC (hydrofluorocarbon) type refrigerants containing no chlorine atom are now candidates as alternative refrigerants. ing. For example, CFC-12
As an alternative refrigerant of HFC-134a (1, 1, 1,
2-Tetrafluoroethane) and the like are candidates for a mixed refrigerant containing HFC-32 (difluoromethane) as an alternative refrigerant for HCFC-22. However, HFC-134
Although HFC-based refrigerants such as a and HFC-32 have no ozone depleting ability at all, they have a long life in the atmosphere, so there is concern about their effect on global warming.

As an alternative refrigerant of CFC-11 (bp = 23.8 ° C.), HCFC having a relatively small ozone depletion ability
-123 (1,1-dichloro-2,2,2-trifluoroethane, bp = 27.5 ° C) and HCFC-141b
(1,1-dichloro-1-fluoroethane, bp = 32
C) is a candidate. However, the ozone layer depleting ability of these HCFC-based refrigerants is small compared to CFC-based refrigerants, and the problem is that they are not absent.

Under the circumstances as described above, there is a demand for a next-generation refrigerant that has no ozone depleting ability and has a short life in the atmosphere. As a refrigerant candidate satisfying these points, various fluorine-containing ether-based refrigerants have recently been studied, and examples thereof include J. L. Ad
The following references by Cock et al. are listed. J. L. Adcock et al. , J. et al. Chemi
cal Thermodynamics, 23 699
(1991) J. L. Adcock et al. , 10th Wi
inter Fluorine Conference,
Abst. # 9 (1991) On the other hand, the lubricating oil used in the refrigeration system is required to have sufficient compatibility with the refrigerant. The use of incompatible lubricants causes a number of serious problems, including: For example, if the lubricating oil is replaced by the refrigerant in the compressor, the lubricity becomes insufficient, or the lubricating oil adheres to the inner wall of the heat exchanger, resulting in a poor heat exchange rate.

Further, the lubricating oil for the refrigeration system is required to have not only good compatibility with the refrigerant but also practically excellent stability, low hygroscopicity and lubricity. .

[0007]

Fluorine-containing ether type refrigerants, which are considered to be promising next-generation refrigerants because they have no ozone depleting ability and have a shorter life in the atmosphere than HFC-type refrigerants, are used. As a lubricating oil for refrigerators, it is necessary to find one having excellent compatibility with a fluorine-containing ether-based refrigerant, stability, low hygroscopicity, and lubricity.

[0008]

The inventors of the present invention have made extensive studies on various lubricating oils. As a result, although hydrocarbon lubricating oils such as mineral oil and alkylbenzene that have been conventionally used when using chlorofluorocarbons as refrigerants have excellent stability and low hygroscopicity, they are not fluorinated ether refrigerants. It was found that they are hardly compatible and cannot be used as refrigerating machine oil.

Further, it has been found that although perfluoropolyether is excellent in stability and low hygroscopicity, its compatibility with a fluorine-containing ether type refrigerant is insufficient in a low temperature region and cannot be used. Furthermore, polyalkylene glycol has insufficient lubricity and stability under the conditions of use of lubricating oil, and its high hygroscopicity causes corrosion of metals and reduction of volume resistivity (closed refrigeration such as refrigerators). Problem with the machine)
Such problems are likely to occur and it cannot be said that the lubricating oil for refrigeration system is practically excellent.

Further, since the polyol ester contains an ester group, it has a high hygroscopic property and is easily hydrolyzed, so that there is a problem in durability. On the other hand, the present inventors have found that the fluorinated aromatic compound represented by the general formula [I] has good compatibility with various fluorinated ether-based refrigerants and the fluorinated ether-based refrigerant and the general formula The present inventors have found that a refrigerant composition comprising the compound [I] exhibits high stability, and completed the present invention.

That is, according to the present invention, a lubricating oil comprising a fluorine-containing aromatic compound represented by the general formula [I], the sum of the number of carbon atoms and the number of oxygen atoms in the molecule is 3 to 6, and , Refrigerant composition R (XRf) _n ... [I] [wherein X is an O or S atom], which contains a fluorine-containing ether type refrigerant having one or more hydrogen atoms in the molecule as an essential component. R has 6 to 6 carbon atoms
It represents 0 n-valent aromatic groups. n represents an integer of 1 to 4. Rf represents a fluorocarbon group or a partial substitution product thereof, and the number of carbon atoms in Rf is in the range of 1 to 25,
And the ratio of the number of fluorine atoms / the number of carbon atoms in Rf is
It is 0.2 or more and 3 or less. In addition, when n is 2 or more, the compound represented by the general formula [I] is a compound of plural kinds of X.
It may be composed of an Rf group. ].

The contents of the present invention will be described in more detail below. As the lubricating oil represented by the general formula [I] in the present invention, for example, a fluorine-containing aromatic compound disclosed in JP-A-5-86382 is used. General formula [I]
In, X is an O or S atom. When X is O, 1) a fluorine-containing aromatic compound can be economically synthesized in a high yield using inexpensive synthetic raw materials, and 2) the fluorine-containing aromatic ether compound has extremely high stability. Is preferred for the reason such as having

R in the general formula [I] has 6 to 6 carbon atoms.
0, preferably 6 to 40, more preferably 6 to 33, n-valent aromatic group is represented. If the carbon number of R is larger than 60, the viscosity becomes too high and it is not suitable for use as a refrigerating machine oil. The aromatic group represented by R has at least one aromatic ring, and may be substituted with a substituent having no aromatic ring. When it has two or more aromatic rings, it is a linking group. May be connected by. The substituent is a monovalent group, and the linking group is a divalent or higher valent group. When these examples are shown together, an alkyl group, a divalent to tetravalent hydrocarbon group or a divalent group is used.
Saturated hydrocarbon group such as tetravalent alicyclic hydrocarbon group, unsaturated hydrocarbon group such as allyl group, halogenated hydrocarbon group such as 2-chloroethyl group, halogen atom such as chlorine and fluorine, hydroxyl group, thiol group , Alkoxy group, nitrile group, nitro group, ether group, thioether group, ester group, carbonyl group, sulfonyl group, sulfinyl group, carboxyl group, carboxylate group, amino group, thiocarbamate group, amide group, imide group, pyridine group , A pyrimidine group,
Piperidine group, triazine group, phosphine group, benzimidazole group, phosphite group, triazole group,
Examples thereof include polar groups such as a tetrazole group, a thiazole group, a thiadiazole group, and various oxygen-containing, nitrogen-containing, phosphorus-containing, and sulfur-containing atoms.

Of the above-mentioned Rs, the case where R has a structure in which an aromatic ring is directly linked to -XRf is preferable because it is particularly excellent in stability and can be easily synthesized. The aromatic group represented by R has a ratio of the number of carbon atoms of the aromatic ring in R / the total number of carbon atoms in R of 0.1 or more, preferably 0.2 or more,
More preferably, it is 1.5 or more.

The value of n in the general formula [I] depends on the valence of R, but from the availability of raw materials 1 to
It is an integer of 4. It is preferably any of 2, 3, 4 and particularly preferably 2. Further, in the general formula [I], when n is 2 or more, the compound of the general formula [I] may be composed of plural kinds of XRf groups. In the general formula [I], Rf represents a fluorocarbon group or a partially substituted product thereof. The fluorocarbon group is
It means a substituent having a structure in which some or all of the hydrogen atoms of various hydrocarbon groups are replaced with fluorine atoms. Examples thereof include a fluoroalkyl group having a saturated structure, a fluoroaryl group having an unsaturated structure, a fluoroaraalkyl group, and the like. Particularly, the fluoroalkyl group and the fluoroalkenyl group are easy to synthesize. It is useful.

The number of carbon atoms in Rf is in the range of 1 to 25, preferably 1 to 10, from the viewpoint of easy availability of raw materials.
More preferably, it is 1-3. The ratio of the number of fluorine atoms / the number of carbon atoms in Rf is 0.2 or more and 3 or less, preferably 0.6 or more and 3 or less, and more preferably 1.5 or more and 3 or less. If this ratio is too low, the compatibility with the fluorine-containing ether-based refrigerant becomes poor, which is not preferable.

Further, as Rf, a part of the fluorine atom or hydrogen atom of the above fluorocarbon group is a halogen atom such as chlorine atom, bromine atom, iodine atom, hydroxyl group, ether group, amino group, nitrile group or ester group, It may be substituted with various substituents that are stable under the conditions of use of refrigerating machine oil, such as an amide group, an acyl group, and a carbonyl-containing group such as a carboxyl group, or a part of the main chain may have an ether structure. These substitutes and the like, which exhibit stability in refrigerating machine oil and the like, may be appropriately selected according to the demand.

When the compound represented by the general formula [I] of the present invention is used alone as a lubricating oil for a refrigerator using a refrigerant containing a fluorine-containing ether, its viscosity is usually Those having a kinematic viscosity at 40 ° C. in the range of 2 to 500 centistokes (hereinafter abbreviated as “cSt”), preferably in the range of 3 to 300 cSt, more preferably in the range of 5 to 170 cSt are particularly preferable. Is in the range of 10 to 150 cSt.

Alternatively, the kinematic viscosity at 100 ° C. is usually 0.5 to 100 cSt, preferably 1 to 50 cS.
t, particularly preferably in the range of 2 to 30 cSt is used. If the viscosity is too low, sufficient lubricity cannot be obtained in the compressor part, and if the viscosity is too high, the rotating torque of the compressor part becomes high, which is not preferable. When the compound represented by the general formula [I] is used as a mixture of a plurality of types or when it is used as a mixture with another type of lubricating oil, the compound represented by the general formula [I] is used. The viscosity itself is not particularly limited, and the viscosity of the mixed system may be in the same range as when the compound represented by the above general formula [I] is used alone.

As described above, the fluorine-containing aromatic compound represented by the general formula [I] is useful as a lubricating oil for a refrigerator used with a fluorine-containing ether type refrigerant. Among them, in particular, the polyvalent fluorine-containing aromatic compound represented by the general formula [II] can be synthesized 1) using inexpensive synthetic raw materials and in a high yield economically, 2) 3) Various non-fluorinated oils (for example, hydrocarbon oils such as mineral oils, alkylbenzenes, poly-α-olefins, polyalkylene glycols, ester oils, etc.)
Since it has excellent compatibility with, it can be used as a mixed oil with these oils and the like, and has many characteristics, and is particularly useful.

R '(XRf') _n '... [II] [wherein X is an O or S atom] R'represents the same aromatic group as R in general formula [I], provided that the number of carbon atoms in R'is 6 to 33. n'represents an integer of 2 to 4. Rf ′ represents a fluorocarbon group or a partial substitution product thereof, like Rf in the general formula [I]. The number of carbon atoms in Rf ′ is in the range of 1 to 25, preferably 1 to
10, more preferably 1 to 3. The ratio of the number of fluorine atoms / the number of carbon atoms in Rf ′ is 0.2 or more and 3 or less, preferably 0.6 or more and 3 or less, and more preferably 1.5 or more and 3 or less.

The compound represented by the general formula [II] is
It may be composed of plural kinds of XRf ′ groups.
R'and XRf 'are directly linked by the aromatic ring moiety in R'. Specific examples of the compound represented by the general formula [II] include those represented by the following formula, as disclosed in JP-A-5-86382.

[0023]

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[0024]

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[0025]

[Chemical 3]

[0026]

[Chemical 4]

[0027]

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[0028]

[Chemical 6]

[0029]

[Chemical 7]

Further, among the compounds represented by the general formula [I], the present inventors have found that, in particular, the compounds of the general formula [III] and the general formula [IV] are 1) a measure of the easiness of concentration in a living body. That is, the so-called "bioconcentration" is low, 2) low hygroscopicity and good electric insulation, and 3) excellent compatibility with hydrocarbon oils such as alkylbenzene and mineral oil. By mixing with hydrocarbon-based oil, characteristics such as low temperature fluidity, low hygroscopicity, electrical insulation, etc. are significantly improved, and cost reduction can be achieved. I found it to be excellent.

[0031]

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[However, R¹, R²Has 1 to 20 carbon atoms
Represents an alkyl group or a hydrogen atom, and R¹And R²Charcoal
The sum of prime numbers ranges from 4 to 20. Rf¹, Rf²Is
A fluorocarbon group, like Rf in the general formula [I],
Represents the partial substitution product. Rf ¹, Rf²Carbon atom in
Is in the range of 1 to 25, preferably 1 to 10,
More preferably, it is 1-3. Also Rf¹, Rf²During ~
The ratio of the number of fluorine atoms / the number of carbon atoms is 0.2 or more and 3
Or less, preferably 0.6 or more and 3 or less, more preferably
It is 1.5 or more and 3 or less. Note that Rf¹And Rf²Is
It may be the same fluorocarbon group or different.
Yes. ]

[0033]

[Chemical 9]

[However, R ³ , R ⁴ and R ⁵ have 1 to 2 carbon atoms.
It is 0 alkyl groups. n represents an integer of 1 to 3. n
When is 2 or 3, the compound represented by the general formula [IV] may be composed of plural kinds of R ³ R ⁴ R ⁵ C-groups. In addition, the total number of carbon atoms of all R ³ R ⁴ R ⁵ C-groups bonded to the aromatic nucleus in the general formula [IV] is in the range of 4 to 25. Rf ³ represents a fluorocarbon group or a partially substituted product thereof, like Rf in the general formula [I]. The number of carbon atoms in Rf ³ is in the range of 1 to 25, preferably 1 to 10, and more preferably 1 to 10.
It is 3. The ratio of the number of fluorine atoms / the number of carbon atoms in Rf ³ is 0.2 or more and 3 or less, preferably 0.6 or more and 3
Hereafter, it is more preferably 1.5 or more and 3 or less. In addition, as the lubricating oil used in the present invention, the compound of the general formula [I] can be used alone or in combination of two or more kinds. Furthermore, if necessary, naphthene-based mineral oil, paraffin-based mineral oil, alkylbenzene, alkylnaphthalene, hydrocarbon-based lubricating oil such as poly-α-olefin, further, polyalkylene glycol, ether-based lubricating oil such as polyphenyl ether, Various lubricants having a structure other than the general formula [I], such as fluorine-based lubricating oils such as perfluoropolyether and polychlorotrifluoroethylene, ester-based lubricating oils such as polyol ester and mixed ester, and carbonate-based lubricating oils such as polycarbonate. It can also be used as a mixture with oil. Of these, hydrocarbon-based lubricating oils are excellent in stability and electric insulation and have low hygroscopicity, and are therefore preferable as lubricating oils to be mixed with the compound of the general formula [I]. Among the hydrocarbon-based lubricating oils, those having an aromatic group such as alkylbenzene and alkylnaphthalene are particularly preferable because they have good compatibility with the compound of the general formula [I], and the mixed oil has low hygroscopicity and is stable. It is a highly practical lubricating oil because of its excellent properties, electrical insulation and lubricating properties. Further, among the alkylbenzenes, a branched alkylalkylbenzene and the general formula [I] or [II]
The oil mixed with the compound (1) is particularly preferable because it has a particularly good compatibility with the fluorine-containing ether type refrigerant.

When the compound of the general formula [I] is mixed with a lubricating oil having another structure as described above, the weight ratio of the compound of the general formula [I] to the whole mixed lubricating oil is It is usually in the range of 0.1% by weight to 99.9% by weight, preferably in the range of 1% by weight to 99% by weight, particularly preferably
5 wt% to 95 wt%, more preferably 10
It is in the range of wt% to 90 wt%.

The fluorine-containing ether type refrigerant used in the present invention has a sum of the number of carbon atoms and the number of oxygen atoms in the molecule of 3 to 3.
6, preferably 3-5. If the sum of the number of oxygen atoms and the number of oxygen atoms in the molecule is larger than 6, the boiling point becomes too high, which is not preferable for use as a refrigerant. The ratio of the number of fluorine atoms / the number of hydrogen atoms contained in the molecule is 0.6 or more in order to reduce flammability, and preferably,
It is 1.0 or more, and more preferably 1.5 or more. Further, the fluorine-containing ether type refrigerant used in the present invention,
In order to shorten the life in the atmosphere and improve the compatibility with the lubricating oil in the present invention, it is preferable to have one or more hydrogen atoms in the molecule. The following can be mentioned as the example.

[0037]

[Chemical 10]

[0038]

[Chemical 11]

[0039]

[Chemical 12]

[0040]

[Chemical 13]

[0041]

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[0042]

[Chemical 15]

[0043]

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Fluorine-containing ether-based cold used in the present invention
Use one type of medium or a mixture of multiple types.
You can In addition, fluoroalkane-based refrigerants or salts
Element-containing fluoroalkane-based refrigerant, perfluoroether-based
It can also be used as a mixture with other types of refrigerants such as refrigerants.
It Here, as an example of the fluoroalkane-based refrigerant, CHF is used.
₃, CH₂F₂, CF₃CH₂F, CF₃CHF₂, C
HF₂CHF₂, CF₃CH₃, CHF₂CH₃, CF
₃CF₂CH₃, CF₃CHFCF₃, CF₃CH₂C
HF₂, CHF₂CF₂CHF₂, CHF₂CF₂CH
₂F, CF₃CF ₂CF₂CH₃, CF₃CHFCHF
CF₃, CF₃CHFCHFCF₂CF₃Etc.
Be done. Examples of chlorine-containing fluoroalkane-based refrigerants include C
HClF₂, CCl₂F₂, CHCl₂F, CH₂Cl
F, CHCl₂CF₃, CHClFCF₃, CH₃CC
l₂F, CH₃CClF₂, CF₃CF₂CHCl₂,
CClF₂CF₂CHClF etc. are mentioned.

When the fluorine-containing ether type refrigerant used in the present invention is used by mixing it with another type of refrigerant as described above, the ratio of the fluorine-containing ether type refrigerant in the present invention is such that the mixed refrigerant as a whole. Usually 1% to 9% by weight
The range is 9%, preferably 5% to 95%, more preferably 10% to 90%. In the refrigerant composition of the present invention, the weight ratio of total amount of refrigerant / total amount of lubricating oil in the refrigeration system is usually in the range of 99/1 to 1/99,
The range is preferably 95/5 to 5/95, and more preferably 90/10 to 10/90.

The refrigerant composition of the present invention, if necessary,
Load-bearing additives (oiliness agents, extreme pressure agents, antiwear agents), metal deactivators such as benzotriazole, rust inhibitors, detergent dispersants, antioxidants such as hindered phenols, defoamers, Additives such as viscosity index improvers, pour point depressants, epoxy-based additives such as alkyl glycidyl ethers and alkyl glycidyl esters can be added.

Specific examples of load-bearing additives include phosphorus-based additives such as tricresyl phosphate and triphenyl phosphate, sulfur-based additives such as diphenyl disulfide,
Chlorinated additives such as chlorotrifluoroethylene polymer,
3,3,4,4,5,5,6,6,7,7,8,8,8
-Fluoride additives such as tridecafluorooctanol,
Additives having a structure having a long-chain alkyl group and polar group such as oleic acid and oleyl alcohol (oil-based agents), organometallic additives such as sulfurized oxymolybdenium phosphorodithioate, and benzotriazoles such as alkyl-substituted benzotriazoles Examples thereof include derivatives. further,
These load-bearing additives can be added singly or, for example, combinations of tricresyl phosphate and oleyl alcohol, combinations of tricresyl phosphate and chlorotrifluoroethylene polymers. Alternatively, a plurality of types may be combined and added.

Hereinafter, the present invention will be specifically described with reference to examples, but the scope of the present invention is not limited to the examples. (Reference Reaction Example 1) 1,300 g of 2,2-bis (4-hydroxyphenyl) -4-methylpentane and 106 g of potassium hydroxide were dissolved in 2020 g of dimethyl sulfoxide, and this solution was put into a 5 liter autoclave, and then in an autoclave. Was replaced with nitrogen, then heated to 60 ° C. and stirred. Furthermore, tetrafluoroethylene was injected under pressure to carry out the reaction. During the reaction, the pressure of tetrafluoroethylene is 3 to 4 kg / cm ^2.
(Gauge pressure). Reaction takes about 1 hour 40
After completion of the reaction in minutes, the reaction solution was taken out, and then dimethyl sulfoxide was distilled off with a rotary evaporator. Next, the obtained oil was washed with distilled water and then distilled under reduced pressure to obtain 2040 g of oil [S1]. (Yield 90%) It was confirmed that the structure of oil [S1] was as shown below by infrared absorption spectrum analysis (FIG. 1) and mass spectrometry.

Mass spectrometry: m / e = 470 (m ⁺ ) Kinematic viscosity (at 40 ° C.) = 109.3 cSt

[0050]

[Chemical 17]

(Reference Reaction Example 2) 2,2-bis (4-hydroxyphenyl) -4-methylpentane was replaced by p-
Reference Reaction Example 1 using tert-octylphenol
Oil [S2] was obtained in the same manner as. Oil [S2]
The structure of was confirmed to be as shown below by infrared absorption spectrum analysis (FIG. 2) and mass spectrometry.

Mass analysis: m / e = 306 (m ⁺ ) Kinematic viscosity (at 40 ° C.) = 6.1 cSt

[0053]

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(Reference Reaction Example 3) Oils [S3] to [S8] were synthesized in the same manner as in the example of JP-A-5-86382. 6.2 g of potassium hydroxide to 200 m of methanol
It was dissolved in 1. To this, 200 ml of a methanol solution containing 12.7 g of 2,2-bis (4-hydroxyphenyl) propane (hereinafter abbreviated as bisphenol A) was gradually added, and sales were expanded at room temperature for about 1 hour. After the reaction, the methanol was dried up to obtain 18.9 g of potassium alkoxide of bisphenol A. This potassium alkoxide (18.9 g) and bisphenol A (56.0 g) were dissolved in dimethyl sulfoxide (200 ml) and placed in a 500 ml capacity micro-bomb.

The system was degassed and returned to normal pressure with an inert gas N ₂ . The reaction vessel was heated to 60 ° C. in an oil bath and tetrafluoroethylene was introduced to start the reaction. Tetrafluoroethylene was supplied so that the system internal pressure (gauge pressure) was kept at ² to 3 kg / cm ^2, and the reaction was carried out for about 5 hours. Pour the reaction control solution into a large amount of water and add 1 to the separated reaction product.
500 ml of 1,2-trichloro-1,2,2-trifluoroethane (hereinafter abbreviated as R-113) was added. The R-113 layer was washed twice with distilled water, dried, and the solvent was removed to give a colorless transparent oil ([S3] 90.
1 wt% content) 113 g was obtained.

After simple distillation (bp 0.20 mmHg, 16
(0 ° C.) Separation treatment was performed using a silica gel column to isolate oil [S3]. Infrared absorption spectrum analysis, mass spectrometry [m / e 428, (M ⁺ ) 413 (M ⁺ -C
From H ₃ )], it was confirmed that this oil [S3] was a compound having the structure shown below. (Kinematic viscosity (at4
0 ° C.) = 26 cSt)

[0057]

[Chemical 19]

(Reference reaction example 4) 10 g of bisphenol A
Was dissolved in 10 ml of tetrahydrofuran, 15 g of triethylamine was added thereto, and the mixture was placed in a four-necked flask equipped with a reflux cooling type stirrer. To this, 180 g of hexafluoropropene trimer C ₉ H ₁₈ (manufactured by US PCR) was added, and the mixture was reacted at 60 ° C. for 6 hours. After the reaction, tetrahydrofuran, excess hexafluoropropene trimer and triethylamine were removed by an evaporator.

50 ml of R-113 was added to the reaction mixture to form a solution, which was washed with dilute hydrochloric acid and water. R-113
After the phase was purified by a silica gel column, the solvent was removed by an evaporator to remove oil [S4] to 47%.
g (yield 97%). Infrared absorption spectrum analysis. From the results of mass spectrometry, it was confirmed that [S4] was a compound having the structure shown below.

[0060]

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(Reference Reaction Example 5) Sodium hydroxide 7.1
g in 20.7 g of water, then 4.0 g of bisphenol A
13.8 g of dimethyl sulfoxide was added to 100 ml
It was charged in a micro-cylinder with a capacity. This micro cylinder was introduced at -78 ° C. After reacting at 70 ° C. for 10 hours, the reaction solution was poured into a large amount of water, and 100 ml of R-113 was added to the separated reaction product.

The lower R-113 phase was washed twice with distilled water and then purified by a silica gel column to remove the solvent to obtain 1.1 g of oil [S5] (yield 18%).
Mass spectrometry [m / L 328 (M ⁺ ), 313 (M ⁺ -C
H ₃ )] and the result of infrared absorption spectrum analysis,
It was confirmed that the oil [S5] was a compound having the structure shown below.

[0063]

[Chemical 21]

Reference Reaction Example 6 In exactly the same manner as Reference Reaction Example 4, except that the compound [G6] was used in place of bisphenol A and hexafluoropropene was used in place of the hexafluoropropene trimer. Oil [S6] was obtained (yield 70%). Gas chromatography analysis and the results of mass spectrometry, the ratio of saturated groups to unsaturated groups, i.e., _{= -CF 2 CHFCF 3 / -CF =} CF-CF 3 6
It was / 54.

[0065]

[Chemical formula 22]

(Reference Reaction Example 7) 17 g of potassium alkoxide of bisphenol A synthesized by the same method as in Reference Reaction Example 3 was dissolved in 100 ml of dimethyl sulfoxide to prepare 1,1-difluoro-1,2,2,2-tetrachloroethane. After adding 65 g, the mixture was heated to 60 ° C. and reacted for about 18 hours.

After the reaction, a large amount of the solution was poured into water, and 100 ml of R-113 was added to the separated reaction product. After the phase-separated R-113 phase was washed twice with distilled water, the solvent was removed to give a solid 23 containing [G7] as a main component.
g was obtained. Of this, 11 g was added to a solution prepared by suspending 9 g of lithium aluminum hydroxide in 200 ml of tetrahydrofuran, and reacted at room temperature for 5 hours and further at 65 ° C. for 5 days. After the reaction, tetrahydrofuran was distilled off and toluene 1 was added.
00 ml was added to make a solution. After washing this with distilled water, the toluene phase was purified by silica gel to obtain 3.5 g of a colorless transparent oil (yield 50%).

From the results of infrared absorption spectrum analysis and mass spectrometry, it was confirmed that [S7] was a compound having the structure shown below. Mass ^{spectrometry: m / e = 356M +,} 341 (M + -C
H ₃ )

[0069]

[Chemical formula 23]

Reaction Reference Example 8 A solution of hexafluoropropene oligomer acid fluoride F [CF (C) was added to a solution prepared by dispersing 10 g of sodium carbonate in 25 ml of diglyme.
F ₃ ) CF ₃ O] _5-8 CF (CF ₃ ) COF (US PC
(Manufactured by R Co., Ltd.) is added, and the mixture is reacted at 80 ° C. for 5 hours.

After the reaction, diglyme was distilled off and the silica gel column was purified to give 15.4 g of compound [G8].
Obtained. Next, 0.24 g of thiophenol and 0.02 g of potassium hydroxide were dissolved in 3 ml of dimethyl sulfoxide,
To this, 10 ml of a 1,3-di (trifluoromethyl) benzene solution containing 3 g of the compound [G8] was added, and the mixture was reacted at 60 ° C. for an hour. After distilling off the solvent, the product was purified with a silica gel column,
2 g of oil [S8] was obtained.

From the results of infrared absorption spectrum analysis, gas chromatography analysis and mass spectrometry, it was confirmed that [S8] was a mixture of substances having the structures shown below. <Compatibility test>

[0073]

Examples 1 to 5 For each of the oils [S1], [S2] and [S3], 0.1 g of oil and various fluorine-containing ether type refrigerants (CHF ₂ OCH ₂ CF ₃ , CH ₃ OCH ₂ CF).
0.9 g of ₂ CF ₃ , CH ₃ CH ₂ OCF ₂ CHF ₂ ) was enclosed in a glass ampoule. In any of Examples 1 to 5, after confirming that the composition was completely uniform at room temperature (22 ° C.), it was gradually cooled in a dry ice-ethanol refrigerant, and the refrigerant and the oil were visually determined. Was measured for the first time and the lower limit temperature of compatibility was determined. The results are shown in Table 1.

[0074]

Examples 6 to 10 Oils [S4] to [S8] were synthesized according to the method described in JP-A-5-86382, and a fluorine-containing ether type refrigerant ( The compatibility with CHF ₂ OCH ₂ CF ₃ ) was investigated. As a result, in each case, the lower limit temperature of compatibility is 0 ° C. or lower,
It was confirmed that good compatibility was exhibited.

[0075]

[Chemical formula 24]

[0076]

Example 11 Oil [S1] 0.1 g and difluoromethyl 1,1,1-trifluoroethyl ether 0.45
After cooling the glass ampoule containing g with liquid nitrogen and reducing the pressure, 1,1,1,2-tetrafluoroethane 0.45
g was introduced. After sealing the glass ampoule, the temperature was raised to room temperature. Next, after confirming that the composition was completely uniform at room temperature (22 ° C.) as in Examples 1 to 5, the composition was gradually cooled in a dry ice-ethanol refrigerant, and the refrigerant and the oil were visually determined. Was measured for the first time and the lower limit temperature of compatibility was determined. The results are shown in Table 1.

As can be seen from Table 1, the oil used in the present invention shows good compatibility with the mixed refrigerant composed of fluorine-containing ether and hydrofluorocarbon.

[0078]

Examples 12 to 14 The lower limit temperature of the compatibility of the oil [S1] / alkylbenzene mixed oil, the oil [S1] / alkyldiphenyl ether mixed oil, and the oil [S1] / mineral oil mixed oil with the fluorine-containing ether-based refrigerant was determined. It measured by the method similar to 1-5. The results are shown in Table 2.

As can be seen from Table 2, the lubricating oil of the present invention represented by the general formula [I] has good miscibility with various hydrocarbon type lubricating oils, and the mixed oil is a fluorine-containing ether type oil. Shows good compatibility with refrigerants.

[0080]

[Comparative Examples 1 to 9] The lower limit of compatibility with various fluorine-containing ether type refrigerants using perfluoropolyether as a lubricating oil and mineral oil was measured by the same method as in Examples 1 to 5. As a result, in both cases, room temperature (22
However, the lower limit temperature of the compatibility was room temperature (22 ° C.) or higher. The results are shown in Tables 1 and 2.

[0081]

[Table 1]

[0082]

[Table 2]

<Lubricity test>

[0084]

Examples 15 and 16 Fluorine-containing ether (CH ₃ CH ₂ OCF ₂ C) was added to each of the oil [S1] / [S2] mixed oil and the oil [S1] / alkylbenzene mixed oil.
The lubrication characteristics of the oil containing 1 wt% of HF ₂ ) were evaluated, and the seizure load was measured by a Falex tester. AST is measured except that the initial oil temperature is 25 ° C.
It was carried out according to MD3233-73 (method A). Table 3 shows the results.

[0085]

Example 17 Oil [S1] / Alkylbenzene mixed oil with tricresyl phosphate (0.5% by weight) added was used to prepare a fluorine-containing ether (CH ₃ CH ₂ OCF) in the same manner as in Examples 15 to 16. ₂ CHF ₂ ) 1 wt
%, And the baking load was measured by a Falex tester. The results are shown in Table 3.

[0086]

[Table 3]

[0087]

Comparative Example 10 The seizure load was measured by a Falex tester using mineral oil. The results are shown in Table 2. Table 2
From the above, it can be seen that the refrigerant composition of the present invention has good lubricating properties. <Bioconcentration test>

[0088]

[Example 18] The test method is "about the test method relating to a new chemical substance" (Environmental Safety No. 5, Yakuhin 615, 49).
Base Station No. 392, July 13, 1974)
Concentration test of chemical substances in the body of seafood> and "O
ECD Guideline for Testing
of Chemicals "(May 12, 198)
1305 stipulated in '305C, Bioaccumulati
on: Degree of Bioconcentrat
Ion in Fish '.

As a concrete test method, first, an exposure test was conducted using test water in which the concentration of oil [S1] was set to 0.01 mg / L and normal carp after acclimation,
Two or four weeks after the exposure, the oil was collected, fragmented, homogenized, centrifuged, and then the concentration ratio of the oil concentrated in the living body was measured by high performance liquid chromatography analysis. The results are shown in Table 4.

[0090]

Examples 19 to 20 In the same manner as in Example 18, oils [S2] and [S3] were subjected to a bioconcentration test. The results are shown in Table 4. From Table 4, it can be seen that among the compounds of the present invention represented by the general formula [I], the compounds represented by the general formula [III] and the general formula [IV] have particularly low bioconcentration properties.

[0091]

[Table 4]

[0092]

EFFECT OF THE INVENTION According to the present invention, when a lubricating oil containing a fluorine-containing aromatic compound represented by the general formula [I] and a fluorine-containing ether type refrigerant are used, there is little influence on ozone layer depletion and global warming, Moreover, a refrigerant composition having good compatibility can be obtained.

[Brief description of drawings]

1 is an infrared absorption spectrum analysis result of [S1] obtained in Reference Reaction Example 1. FIG.

2 is an infrared absorption spectrum analysis result of [S2] obtained in Reference Reaction Example 2. FIG.

Claims (1)

[Claims] 1. A lubricating oil comprising a fluorine-containing aromatic compound represented by the general formula [I], wherein the sum of the number of carbon atoms and the number of oxygen atoms in the molecule is 3 to 6 and 1 hydrogen atom
A refrigerant composition containing as an essential component a fluorine-containing ether-based refrigerant having one or more. R (XRf) _n ... [I] [wherein X is an O or S atom. R has 6 to 6 carbon atoms
It represents 0 n-valent aromatic groups. n represents an integer of 1 to 4. Rf represents a fluorocarbon group or a partial substitution product thereof, and the number of carbon atoms in Rf is in the range of 1 to 25,
And the ratio of the number of fluorine atoms / the number of carbon atoms in Rf is
It is 0.2 or more and 3 or less. In addition, when n is 2 or more, the compound represented by the general formula [I] is a compound of plural kinds of X.
It may be composed of an Rf group. ]