JPH09194829A - Working medium for refrigerating equipment and refrigerating apparatus using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a working medium which reduces the coefficient of friction of sliding parts and markedly improves their abrasion resistance. SOLUTION: This medium comprises a fluorocarbon refrigerant, a refrigerator oil and an ammonium perfluoroalkycarboxylate represented by the formula (wherein (n) is an integer of 3-11, R<1> and R<2> are each hydrogen, a 1-3C alkyl, benzyl or phenethyl, provided that they may be the same with each other; and R<3> is hydrogen, a 5-24C alkyl, unsaturated alkyl, benzyl or phenethyl).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a working medium for a refrigerant compression type refrigerating apparatus, and more particularly to a working medium for a refrigerant compressor such as a refrigerator, a room air conditioner, a package air conditioner and a refrigerator, and a refrigerating apparatus using the same.

[0002]

2. Description of the Related Art At present, CFC is used as a refrigerant for refrigeration equipment.
12 (dichlorodifluoromethane) and HCFC22 (monochlorodifluoromethane) are used. These CFC (chlorofluorocarbon) -based refrigerants and HC
FC (hydrochlorofluorocarbon) -based refrigerants have been completely abolished from the viewpoint of environmental protection.

Possible alternative refrigerants are HFC (hydrofluorocarbon: fluorinated hydrocarbon) type refrigerants which do not contain chlorine in the molecule and have a boiling point close to that of currently used refrigerants, and two or more of them. Mixed mixed refrigerants are mentioned.

Refrigerating machine oil is used in compressors for refrigerating and air-conditioning machines such as refrigerators, room air conditioners, packaged air conditioners, and refrigerators, and plays a role of lubrication, sealing, cooling and the like of sliding parts thereof. In recent years, this compressor has been required to save energy, be small in size, have low noise, and be highly efficient, and along with this, the usage conditions of refrigerating machine oil have become severe. Therefore, refrigerating machine oil having excellent lubricity, especially wear resistance, is required.

As refrigerating machine oil, naphthene-based or paraffin-based mineral oil or alkylbenzene is CFC-based, HCFC-based.
It is widely used because of its good compatibility with the system refrigerants.
However, these refrigerating machine oils do not dissolve in HFC refrigerants at all. Therefore, as refrigerating machine oil compatible with these,
A polyol ester, which is an aliphatic synthetic oil having a polar group in the molecule, was developed (JP-A-62-13912, JP-A-3).
No. 505602, JP-A-4-183788).

Further, since the HFC type refrigerant does not contain chlorine in its molecule, the lubricating effect of the refrigerant itself cannot be expected at all as compared with the conventional refrigerant. Therefore, further lubricity is required for the refrigerating machine oil.

Various additives are used in general refrigerating machine oil, and a lubricity improver is one of them. As a lubricity improver for mineral oil-based refrigerating machine oils, for example, tertiary phosphate-based phosphorus compounds such as triphenyl phosphate and tricresyl phosphate are known (edited by Toshio Sakurai: Petroleum Product Additives, Shokobo Showa Showa). May 15, 1988).

Further, as the lubricity improver for refrigerating machine oil compatible with HFC type refrigerants, (1) secondary phosphite, acid phosphate (JP-A-4-28792),
(2) Phosphoric acid ester of polyoxyalkylene alkyl ether (JP-A-62-79295), (3) Amine salt of secondary phosphite or acid phosphate (JP-A-63-90597, JP-A-3-90597). 3940
No. 0), (4) Organic molybdenum compound
39494).

However, none of these additives has sufficient effects in terms of wear resistance and ensuring reliability. Also,
There are drawbacks such as poor heat resistance stability and solubility with a fluorohydrocarbon refrigerant or refrigerating machine oil, which lowers the efficiency of the refrigeration cycle and lowers the reliability of the compressor.

[0010]

DISCLOSURE OF THE INVENTION Refrigerant compressors for refrigerators and air conditioners include scroll, reciprocator, screw, rotary equal volume type (flow rate is determined by rotational speed) compressors and turbo type capacity type ( There is a compressor that does not determine the flow rate depending on the rotation speed. A schematic structure of a rotary compressor as an example of the compression means is shown in FIG.

In the compressor, a roller 4 is incorporated on the outer periphery of a crank 3 which is directly connected to a shaft 2 of a motor 1, and a cylinder block 5 is installed so that a part of the roller 4 is in close proximity with a predetermined gap. Has been done. Therefore, the rotation of the shaft 2 causes the roller 4 to slide relative to the crank 3, and at the same time, the roller 4 and the inner peripheral surface of the cylinder block 5 swing and rotate in the cylinder while changing the proximity points.

A vane 6 is provided in the vane groove of the cylinder block 5. The vane 6 is configured to be constantly pressed against the roller 4 by the spring 7 installed on the back surface of the vane 6 and the oil introduction passage 8 under the discharge pressure. In this compressor, the compression reaction force of the refrigerant gas, the frictional force of each part,
The radial force acting on the shaft 2, such as the pressing force from the vane 6, is supported by the side plates 9 and 10 installed so as to cover both end surfaces of the cylinder block 5.

All of these mechanical components are housed in the chamber 11, and the refrigerant is sucked directly into the cylinder from the suction pipe 12. On the other hand, the compressed gas is once discharged into the chamber 11, the oil is separated by the change in the flow velocity and the collision with the chamber 11, and the refrigerant gas is discharged from the discharge pipe 13 to the heat exchanger.

Next, the refrigeration cycle will be described. Fig. 2 shows the configuration of the heat pump refrigeration cycle for room air conditioners and package air conditioners that also function as air conditioning.

When the room is cooled, the high-temperature and high-pressure refrigerant gas adiabatically compressed by the discharge pipe of the compressor 14 passes through the four-way valve 15 and is cooled by the outdoor heat exchanger 16 (used as a condenser). It becomes a high-pressure liquid refrigerant. This refrigerant is adiabatically expanded by the expansion means 17 (for example, a capillary tube or a thermal expansion valve) to become a low-temperature low-pressure liquid containing a slight amount of gas, and is stored in an indoor heat exchanger 18 (used as an evaporator). Then, heat is obtained from the air in the room to pass through the four-way valve 15 again to reach the compressor 14 in a low temperature gas state. When heating the interior of the room, the flow of the refrigerant is changed in the opposite direction by the four-way valve 15, which has the opposite effect.

This rotary compressor requires refrigerating machine oil having excellent wear resistance because the frictional condition of the sliding portion is severe.

In view of the above situation, an object of the present invention is to provide a working medium for a refrigerating machine having excellent wear resistance and a refrigerating machine using the working medium.

[0018]

The gist of the present invention to achieve the above object is as follows.

In a working medium for a refrigerating machine composed of a fluorinated hydrocarbon refrigerant and refrigerating machine oil, there is provided a working medium for a refrigerating machine characterized by containing an ammonium salt of perfluoroalkylcarboxylic acid.

The ammonium salt of perfluoroalkylcarboxylic acid has the following formula

[0021]

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(In the formula, n is an integer of 3 to 11, R ¹ and R ² are hydrogen, an alkyl group having 1 to 3 carbon atoms, a benzyl group or a phenethyl group, and R ¹ and R ² are the same as each other. Good, R
³ represents hydrogen, an alkyl group having 5 to 24 carbon atoms, an unsaturated alkyl group, a benzyl group, or a phenethyl group. ).

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION As the fluorohydrocarbon refrigerant, 1,1,1,2-tetrafluoroethane (CF ₃ CH ₂
F; HFC134a), difluoromethane (CH ₂ F ₂ ;
HFC32), 1,1,1,2,2-pentafluoroethane _{(CF 3 CHF 2; HFC125)} , 1,1,2,2- tetrafluoroethane _{(CHF 2 CHF 2; HFC134)} ,
1,1,1-trifluoroethane (CF ₃ CH ₃ ; HFC1
43a) alone or R407C (HFC32: HF) in which two or more kinds of these fluorohydrocarbon refrigerants are mixed.
C125: HFC143a = 23 wt%: 25 wt%: 52
wt%), R410A (HFC32: HFC125 = 50
wt%: 50 wt%), R410B (HFC32: HFC1
25 = 45 wt%: 55 wt%).

Of these, R410A, which is used as an alternative refrigerant to the HCFC22, has a discharge pressure of the compressor which is about 1.6 times that of the HCFC22 when used in the same environment. The radial load increases with this.

As the refrigerating machine oil, polyol ester,
Examples include polyethers, polycarbonates, naphthenic mineral oils, paraffinic mineral oils, and alkylbenzenes. Among these, the most representative polyol ester will be described.

The polyol ester is a polyol ester synthesized from a polyhydric alcohol and a monovalent fatty acid, a complex type synthesized from a polyhydric alcohol and a divalent fatty acid, or a divalent and monovalent mixed fatty acid. is there. Examples of polyhydric alcohols include neopentyl glycol, trimethylolpropane, pentaerythritol, and dipentaerythritol. Examples of monovalent fatty acids include pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, 2-methylbutanoic acid, 2-methylpentanoic acid,
There are 2-methylhexanoic acid, 2-ethylhexanoic acid, isooctanoic acid, 3,5-trimethylhexanoic acid and the like, and these are used alone or in combination of two or more kinds of mixed fatty acids. The divalent fatty acids include adipic acid, pimelic acid, suberic acid, azelaic acid and sebacic acid.

The following are ammonium salts of perfluoroalkylcarboxylic acids, which are lubricity improvers.

Ammonium salt of perfluorobutanoic acid,
There are anilinium salt, p-methylanilinium salt, p-methoxyanilinium salt, tribenzylammonium salt, butylammonium salt, octylammonium salt, laurylammonium salt, stearylammonium salt, tetracosaammonium salt and oleylammonium salt.

Further, ammonium salts of perfluoropentanoic acid, anilinium salts, p-methylanilinium salts,
There are p-methoxyanilinium salt, tribenzyl ammonium salt, butyl ammonium salt, octyl ammonium salt, lauryl ammonium salt, stearyl ammonium salt, tetracosa ammonium salt, and oleyl ammonium salt.

Further, ammonium salt of perfluorohexanoic acid, anilinium salt, p-methylanilinium salt,
There are p-methoxyanilinium salt, tribenzyl ammonium salt, butyl ammonium salt, octyl ammonium salt, lauryl ammonium salt, stearyl ammonium salt, tetracosa ammonium salt, and oleyl ammonium salt.

Further, ammonium salt of perfluoroheptanoic acid, anilinium salt, p-methylanilinium salt,
There are p-methoxyanilinium salt, tribenzyl ammonium salt, butyl ammonium salt, octyl ammonium salt, lauryl ammonium salt, stearyl ammonium salt, tetracosa ammonium salt, and oleyl ammonium salt.

Further, ammonium salt of perfluorooctanoic acid, anilinium salt, p-methylanilinium salt,
There are p-methoxyanilinium salt, tribenzyl ammonium salt, butyl ammonium salt, octyl ammonium salt, lauryl ammonium salt, stearyl ammonium salt, tetracosa ammonium salt, and oleyl ammonium salt.

Further, ammonium salt of perfluorononanoic acid, anilinium salt, p-methylanilinium salt, p
-Methoxyanilinium salt, tribenzylammonium salt, butylammonium salt, octylammonium salt,
Lauryl ammonium salt, stearyl ammonium salt,
There are tetracosa ammonium salt and oleyl ammonium salt.

Further, ammonium salt of perfluorodecanoic acid, anilinium salt, p-methylanilinium salt, p
-Methoxyanilinium salt, tribenzylammonium salt, butylammonium salt, octylammonium salt,
Lauryl ammonium salt, stearyl ammonium salt,
There are tetracosa ammonium salt and oleyl ammonium salt.

Further, perfluoroundecanoic acid ammonium salt, anilinium salt, p-methylanilinium salt, p-methoxyanilinium salt, tribenzylammonium salt, butylammonium salt, octylammonium salt, laurylammonium salt, stearylammonium salt. , Tetracosa ammonium salt, oleyl ammonium salt.

Further, ammonium salt of perfluorolauric acid, anilinium salt, p-methylanilinium salt,
Examples include p-methoxyanilinium salt, tribenzyl ammonium salt, phenethyl ammonium salt, butyl ammonium salt, octyl ammonium salt, lauryl ammonium salt, stearyl ammonium salt, tetracosa ammonium salt, oleyl ammonium salt.

As the ammonium salt of perfluoroalkylcarboxylic acid, oleyl ammonium salt is more preferable.

The blending ratio of the ammonium salt of perfluoroalkylcarboxylic acid, which is a lubricity improver, is 0.01 to 5% by weight, and the blending ratio is 0.1 to 1% by weight, based on the above-mentioned refrigerating machine oil. More preferably.

This is because abrasion resistance cannot be sufficiently obtained at a compounding ratio of less than 0.01% by weight of the ammonium salt of perfluoroalkylcarboxylic acid. On the other hand, when the compounding ratio of the ammonium salt of perfluoroalkylcarboxylic acid exceeds 5% by weight, it is not completely dissolved in the refrigerating machine oil, which causes the phenomenon of clogging of the dryer or the capillary tube.

Incidentally, an antioxidant, an acid scavenger, a defoaming agent, a metal deactivator, etc. may be added to the working medium as long as the object of the present invention is not impaired.

By adding ammonium salt of perfluoroalkylcarboxylic acid to the refrigerating machine oil, a strong adsorption film is formed on the sliding surface to prevent the metal from contacting each other, reduce the friction coefficient, and improve the wear resistance. Improve dramatically.

Hereinafter, the present invention will be described in more detail with reference to Examples.

Examples 1 to 12 The following were used as the fluorohydrocarbon refrigerant (HFC), refrigerating machine oil, and ammonium salt of perfluoroalkylcarboxylic acid as a lubricity improver.

Fluorohydrocarbon type refrigerant: HFC134a was used.

Refrigerating machine oil: Carboxylic acid ester of pentaerythritol was used. The viscosity grade is VG32.

The following were used as lubricity improvers.

[0047]

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[0048]

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[0049]

[Chemical 6]

[Comparative Examples 1 to 4] The following were used as the fluorohydrocarbon refrigerant (HFC), the refrigerating machine oil, and the lubricity improver.

Fluorohydrocarbon type refrigerant: HFC134a was used.

Refrigerating machine oil: Carboxylic acid ester of pentaerythritol was used. The viscosity grade is VG32.

The following were used as lubricity improvers.

[0054]

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The abrasion resistance of the refrigerating machine oil containing 0.5% by weight of these lubricity improvers was evaluated by the following method using a Falex tester.

A rotary shaft (pin) having a diameter of about 6 mm is provided with two Vs.
Place the block symmetrically from the left and right, and soak it in the refrigerator oil filled in the oil cup. HFC134a 150m in oil
Blow for 10 minutes at a flow rate of 1 / min to saturate the oil. Continue blowing during the test. Then load 250 lbs,
Operated for 5 hours at an oil temperature of 100 ° C and a rotation speed of 290 rpm,
The total wear depth of the pin and the V block was calculated from the load-corrected scale change of the ratchet, which is the load mechanism of the Falex tester, and was used as the wear amount. The warm-up operation was performed at 50 lb for about 10 minutes while the temperature was raised from room temperature to 100 ° C.

Table 1 shows the results of the Falex test conducted on the polyol ester. As is clear from Table 1, the working medium for a refrigerating machine of the present invention has a smaller amount of wear and is superior in wear resistance as compared with the base oil alone and the lubricity improver used in Comparative Examples, and at the same time, the friction coefficient is also reduced. ing. In particular, the working medium containing the oleyl ammonium salt of perfluoroalkylcarboxylic acid has excellent wear resistance.

[0058]

[Table 1]

[Examples 13 to 20 and Comparative Examples 5-1
0] Next, in Examples 1 to 12 above, ammonium salt G of perfluoroalkylcarboxylic acid, which was confirmed to improve wear resistance, was used, and the addition amount of the lubricity improver and the type of refrigerating machine oil were changed. The abrasion resistance was evaluated using a Falex tester.

Fluorohydrocarbon refrigerant: HFC134a was used.

Refrigerating machine oil: carboxylic acid ester of trimethylolpropane (viscosity grade VG32), polyether (viscosity grade VG68), polycarbonate (viscosity grade VG32), naphthenic mineral oil (viscosity grade VG56), alkylbenzene (viscosity). The grade used was VG56).

With respect to the refrigerating machine oil in which the lubricity improver was blended with each refrigerating machine oil in a predetermined ratio, the abrasion resistance was evaluated under the following test conditions. HFC134a flow rate 150 ml / min, load 100 lb, oil temperature 120 ° C., rotation speed 290 rpm,
It took 5 hours and about 10 minutes with a 50 lb break-in run. The amount of wear was determined by the same method as in Example 1.

Table 2 shows the results of Examples and Comparative Examples. As is clear from Table 2, the working medium for a refrigerating machine of the present invention has a smaller amount of wear and is excellent in wear resistance as compared with Comparative Examples in which the base oil alone is used, regardless of the type of the base oil. As can be seen from Comparative Example 6, even if the oleyl ammonium salt of perfluoroalkylcarboxylic acid is added to the refrigerating machine oil in an amount of 0.005% by weight, the wear resistance is poor.

[0064]

[Table 2]

[Example 21 and Comparative Examples 11 and 12] Thermal stability was evaluated using the ammonium salt G of perfluoroalkylcarboxylic acid which was confirmed to improve the abrasion resistance in Examples 1 to 12 above. did. As a comparative example, base oil alone and lubricity improver N were used.

Fluorohydrocarbon type refrigerant: R407C was used.

Refrigerating machine oil: Carboxylic acid ester of pentaerythritol was used. The viscosity grade is VG68.

The above-mentioned fluorohydrocarbon refrigerant and refrigerating machine oil were sealed in a glass ampoule tube at a weight ratio of 1: 1 and a shield tube test was conducted. The lubricity improver was added to the refrigerating machine oil in an amount of 0.5% by weight. Copper, iron, and aluminum are made to coexist in the catalyst, and oil after heating at 175 ° C. for 21 days is 1 /
The total acid value was determined by titrating with a 10N-KOH aqueous solution (isopropanolic).

The results of evaluation of thermal stability are shown in Table 3. As is clear from the table, the working medium for a refrigerating apparatus of the present invention has a small increase in total acid value and excellent heat resistance stability as compared with the base oil alone and the lubricity improver of Comparative Example 12. Also, no discoloration of the catalyst was observed.

[0070]

[Table 3]

Next, using the ammonium salt G of perfluoroalkylcarboxylic acid, which was confirmed to improve the wear resistance in Examples 1 to 12, the compatibility between the fluorohydrocarbon refrigerant and the refrigerating machine oil was evaluated. evaluated. For comparison, refrigerating machine oil alone and O as a lubricity improver were used.

Fluorohydrocarbon refrigerant: HFC134a was used.

Refrigerating machine oil: Carboxylic acid ester of pentaerythritol was used. The viscosity grade is VG32.

The compatibility between the above-mentioned fluorohydrocarbon type refrigerant and refrigerating machine oil was evaluated according to JIS K2211. The lubricity improver was added to the refrigerating machine oil in an amount of 0.5% by weight.

The results of compatibility evaluation are also shown in Table 3.
As is clear from Table 3, the working medium for a refrigerating apparatus of the present invention does not impair the compatibility between the fluorohydrocarbon-based refrigerant and the refrigerating machine oil, and has a higher fluidity than the lubricity improver of Comparative Example 13. Shows excellent solubility in chlorinated hydrocarbon refrigerants and refrigeration oils.

In a refrigeration cycle in which an actual rotary compressor is incorporated, the refrigerating machine oil alone and the ammonium salt G of perfluoroalkylcarboxylic acid as a lubricity improver are added in an amount of 0.
Refrigerating machine oil added with 5% by weight and dilaurylhydrogen phosphite N as a lubricity improver 0.5% by weight
The added refrigerating machine oil was used and operated under constant conditions for a fixed time to compare the wear amounts of the outer circumferences of the rollers.

R410A was used as the fluorohydrocarbon refrigerant, and the refrigerating machine oil shown in Example 21 was used.

The most severe sliding surface of this rotary compressor is between the roller and the vane. Therefore, the wear resistance was evaluated by measuring the amount of wear on the outer circumference of the roller.

FIG. 3 shows the relationship between the outer wear of the roller and the running time.
Shown in Refrigerating machine oil containing dilaurylhydrogen phosphite as a lubricity improver has a small amount of initial wear, but wear increases significantly when the friction time is long.
Also, since the thermal stability is poor, the total acid number of the oil after the test is high,
Adhesion was found on the capillary tube, which is the expansion means of the refrigeration cycle. On the other hand, if the refrigerating machine oil alone is R410
In A, the vane pressing force is increased due to the high discharge pressure. Therefore, the wear amount is slightly larger than that of the HCFC22 / naphthenic mineral oil of the current combination, and the wear cannot be sufficiently suppressed.

On the other hand, the refrigerating machine oil containing the ammonium salt of perfluoroalkylcarboxylic acid as the lubricity improver has less wear than the refrigerating machine oil alone, has a low total acid value of the oil after the test, and is frozen. No blockage of the capillary tube, which is the expansion means of the cycle, was observed.

From the above results, by adding 0.01% by weight or more of these ammonium salts of perfluoroalkylcarboxylic acid to the refrigerating machine oil, the resistance of the working medium for the refrigerating machine can be improved regardless of the kind of the refrigerating machine oil. It was confirmed that the wear property was significantly improved and the friction coefficient was reduced.

It was confirmed that by using the working medium for a refrigerating apparatus of the present invention in a refrigerating apparatus, abrasion of the sliding portion is suppressed, the refrigerating cycle is not blocked, and the reliability is greatly improved. .

In the present invention, the results of the actual evaluation are described only for the polyol ester which is well dissolved in the chlorine-free alternative refrigerant. However, for example, an oil for ensuring the oil return from the refrigeration cycle to the compressor is used. Install a recovery mechanism, use fluorinated hydrocarbon refrigerants such as propane and isobutane,
It can be applied to a refrigeration cycle using mineral oil or alkylbenzene which is insoluble in a hydrocarbon-based refrigerant by slightly mixing pentane. In addition, an antioxidant, an acid scavenger, an antifoaming agent, within the range that does not impair the lubricity and the compatibility with the refrigerant.
You may mix | blend a metal deactivator etc.

[0084]

The working medium for a refrigerating apparatus of the present invention is a composition comprising a fluorocarbon-based refrigerant and a refrigerating machine oil,
By adding 0.01% by weight or more of ammonium salt of perfluoroalkylcarboxylic acid, the refrigeration cycle is not blocked, abrasion of the sliding parts of the compressor is suppressed, the friction coefficient is reduced, and highly reliable refrigeration is achieved. The device is obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a rotary compressor.

FIG. 2 is a diagram illustrating a refrigeration cycle of a refrigeration system.

FIG. 3 is a graph showing the relationship between the amount of wear on the outer circumference of the roller and the operating time.

[Explanation of symbols]

1 ... Motor, 2 ... Shaft, 3 ... Crank, 4 ... Roller, 5 ... Cylinder block, 6 ... Vane, 7 ... Spring, 8
... Oil introduction passage, 9, 10 ... Side plate, 11 ... Chamber, 12 ... Suction pipe, 13 ... Discharge pipe, 14 ... Compressor, 15 ... Four-way valve, 16 ... Outdoor heat exchanger, 17 ... Expansion means, 18 ... Indoor heat exchanger.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location F25B 1/00 395 F25B 1/00 395A 13/00 13/00 A // C10N 30:06 40: 30 (72) Inventor, Juichi Arai, 7-1, 1-1 Omika-cho, Hitachi-shi, Ibaraki Hitachi Ltd., Hitachi Research Laboratory

Claims (10)

[Claims] 1. A working medium for a refrigerating machine comprising a fluorohydrocarbon refrigerant and refrigerating machine oil, wherein an ammonium salt of perfluoroalkylcarboxylic acid is mixed. 2. A fluorohydrocarbon refrigerant and a refrigerating machine oil are represented by the following formula: (In the formula, n is an integer of 3 to 11, R ¹ and R ² are hydrogen, an alkyl group having 1 to 3 carbon atoms, a benzyl group or a phenethyl group, and R ¹ and R ² may be the same as each other. ³ represents hydrogen, an alkyl group having 5 to 24 carbon atoms, an unsaturated alkyl group, a benzyl group, and a phenethyl group.) A perfluoroalkylcarboxylic acid ammonium salt represented by Working medium. 3. The ammonium salt of perfluoroalkylcarboxylic acid is 0.01 to 5% by weight based on the refrigerating machine oil.
The working medium for a refrigerating apparatus according to claim 1 or 2, which includes the working medium. 4. The working medium for a refrigerating apparatus according to claim 1, wherein the ammonium salt of perfluoroalkylcarboxylic acid is an oleylammonium salt of perfluoroalkylcarboxylic acid. 5. The working medium for a refrigerating machine according to claim 1, wherein the refrigerating machine oil is a polyol ester. 6. A refrigeration compressor, a condenser for condensing the refrigerant in the working medium compressed by the refrigeration compressor, an expansion means for adiabatically expanding the refrigerant condensed by the condenser, and the expansion means. In a refrigerating apparatus including an evaporator that evaporates the refrigerant expanded by the above, the working medium is a refrigeration characterized in that an ammonium salt of perfluoroalkylcarboxylic acid is mixed with a fluorohydrocarbon refrigerant and refrigerating machine oil. apparatus. 7. A refrigeration compressor, a condenser for condensing the refrigerant in the working medium compressed by the refrigeration compressor, an expansion means for adiabatically expanding the refrigerant condensed by the condenser, and the expansion means. In a refrigerating apparatus provided with an evaporator that evaporates the refrigerant expanded by the above, the working medium is a fluorohydrocarbon-based refrigerant and refrigerating machine oil. (In the formula, n is an integer of 3 to 11, R ¹ and R ² are hydrogen, an alkyl group having 1 to 3 carbon atoms, a benzyl group or a phenethyl group, and R ¹ and R ² may be the same as each other. ³ represents hydrogen, an alkyl group having 5 to 24 carbon atoms, an unsaturated alkyl group, a benzyl group, and a phenethyl group), and is a working medium containing an ammonium salt of a perfluoroalkylcarboxylic acid represented by Refrigerating device. 8. The ammonium salt of perfluoroalkylcarboxylic acid is 0.01 to 5% by weight based on the refrigerating machine oil.
The refrigerating apparatus according to claim 6 or 7, which comprises. 9. The refrigerating apparatus according to claim 7, wherein the ammonium salt of perfluoroalkylcarboxylic acid is an oleylammonium salt of perfluoroalkylcarboxylic acid. 10. The refrigerating apparatus according to claim 6, wherein the refrigerating machine oil is a polyol ester.