JP2010139171A - Refrigerant compressor and refrigerating cycle device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress increase in an acid value of refrigerating machine oil in a refrigerant compressor and a refrigerating cycle device using the refrigerating compressor compared to a conventional refrigerant compressor, so as to improve durability. <P>SOLUTION: A refrigerant filled in the refrigerant compressor is R410A, R407C or R404A, and polyol ester oil is used for base oil. As an acid scavenger, refrigerating machine oil including an alkyl glycidyl ester compound is used. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention secures reliability in the case of using a hydrolyzable lubricating oil such as an ester-based refrigeration oil in a household heat pump refrigeration cycle using an HFC-based refrigerant.

  Conventionally, HCFC-based R22 has been used as a refrigerant for home room air conditioners. However, from the viewpoint of protecting the global environment, it is shifting to HFC-based ones that do not contain chlorine in the molecule. As an alternative, R410A and R407C in which R32, 125 and 134a are used alone or in combination of two or more of these may be mentioned. However, since the HFC-type refrigerant has a molecular polarization state different from that of the HCFC-type refrigerant, the compatibility with the conventional mineral oil is inferior, and the oil return property in the cycle is lowered. Therefore, a method of ensuring oil return without changing the basic configuration of the refrigeration cycle using synthetic oil such as ester oil as the refrigerating machine oil having the required solubility is employed.

  However, this refrigerating machine oil is highly hydrolyzable, and if there is moisture in the cycle, it causes a hydrolysis reaction and decomposes into raw fatty acids and alcohol. This raw fatty acid increases the total acid value of the refrigerating machine oil, and as a result, causes corrosion wear of the sliding portion. Further, when the raw fatty acid reacts with a metal to form a fatty acid metal salt, it adheres to the cycle and becomes a cause of cycle clogging.

  As a countermeasure, Patent Document 1 discloses a method of adding a cycloglycidyl ether compound as an acid scavenger to refrigerating machine oil. Further, Patent Document 2 discloses a method of adding a carbodiimide compound. Further, Patent Document 3 discloses a method using glycidyl ester, glycidyl ether or the like, which is an epoxy compound, as an additive for trapping moisture or acid in oil of refrigeration oil for hydrocarbon (HC) refrigerant.

JP-A-8-231972 JP-A-8-120288 JP-A-2005-283106

  Although the above Patent Document 1 is highly stable, the reactivity with the acid is slow compared to the production rate of the raw fatty acid by hydrolysis reaction or the like, so that the fatty acid cannot be captured immediately.

  Although the above Patent Document 2 is highly reactive with acid and moisture, it is consumed quickly, so it is very effective for capturing initial moisture, but it can handle large amounts of acid produced by thermal decomposition of refrigerating machine oil. Can not.

  Although the said patent document 3 shows use of an epoxy compound etc. as an acid scavenger, the specific substance is not designated. Moreover, hydrocarbon is designated as the refrigerant.

  When ester oil is used as refrigerating machine oil, acid generated by hydrolysis reaction causes corrosion and wear of sliding parts, and metal soap generated by reaction with metal causes malfunction of motor-operated valves. there is a possibility.

  Therefore, an object of the present invention is to suppress an increase in acid value of refrigeration machine oil and improve durability in a refrigerant compressor and a refrigeration cycle apparatus using the refrigerant compressor as compared with a conventional refrigerant compressor.

The object of the present invention is to
A motor having a rotor and a stator in an airtight container for storing refrigerating machine oil;
A rotating shaft fitted to the rotor;
In the refrigerant compressor that houses the compression unit connected to the motor via the rotating shaft,
The refrigerant sealed in the refrigerant compressor is R410A, R407C or R404A,
This is achieved by using a refrigerating machine oil based on a polyol ester oil and containing an alkyl glycidyl ester compound as an acid scavenger.

  The alkyl glycidyl ester compound has a structure represented by the following formula (1).

（但し、前記式中、Ｒは、独立して炭素数４〜１２のアルキル基を表す）

(However, in said formula, R represents a C4-C12 alkyl group independently.)

  ADVANTAGE OF THE INVENTION According to this invention, durability of a refrigerant compressor and the refrigerating cycle apparatus using the same can be improved.

  Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. The refrigerant compressor and the refrigeration cycle apparatus using the same according to the present embodiment are mainly characterized in that hydrofluorocarbon is used as a refrigerant and a predetermined polyol ester is used as refrigeration oil, as will be described later. Here, after describing the refrigeration cycle apparatus in which the refrigerant compressor according to the present embodiment is used, the refrigerant compressor will be described.

  In the drawings referred to here, FIG. 1 is a cross-sectional view of a hermetic refrigerant compressor. The hermetic refrigerant compressor includes a rotary method, a scroll method, a reciprocating method, and the like, and will be described using an example of a scroll-type hermetic refrigerant compressor. Among them, the scroll compressor has a sliding contact with the fixed scroll as a sliding part, so that the temperature does not easily increase instantaneously, and the temperature rises to a temperature at which a high-performance acid scavenger with a high residual rate reacts sufficiently. There are few things. In the case of a rotary type compressor, the vane and the roller are in point contact, and the temperature of the sliding portion is likely to increase. In the case of a reciprocating compressor, the cylinder and the piston are in surface contact with each other. However, since the viscosity of the refrigerating machine oil is low, oil film formation is severe and the sliding part tends to generate heat.

  In this refrigerant compressor, a compressor section 2 and an electric motor 3 are housed in a sealed case 1 that also serves as an oil reservoir. The compressor unit 2 includes a turning scroll 4, a fixed scroll 5, a frame 6, a crankshaft 7, and an Oldham ring 8 as main components. A suction pipe 9 communicating with an external cycle is hermetically connected to the case 1 which is a sealed container. The motor includes a rotor 10 and a stator 11, and a cast iron crankshaft 7 is fitted to the rotor 10. The crankshaft 7 has an eccentric portion 12, and a shaft hole 13 is formed in a hollow shape on one end side.

  The outer periphery of the frame 6 is fixed to the hermetic container 1 and includes a bearing that receives the rotation of the crankshaft 7. An orbiting scroll 4 is rotatably attached to the eccentric portion 12 of the crankshaft 7, and an Oldham ring 8 slides in a groove provided on the frame 6 and a groove provided on the base plate on the side opposite to the wrapping scroll 4. The orbiting scroll is revolved without rotating.

  In addition, refrigerating machine oil 14 is stored at the bottom, and this refrigerating machine oil is supplied to the sliding part. In the refrigerating machine oil 14, an acid scavenger 14a is added. Incidentally, there is a slot (not shown) for winding the magnet wire around the stator 11 in the electric motor 3, and the surface thereof is covered with an insulating film as is well known, and the insulating film in this embodiment is It is made of an ester resin.

  FIG. 2 shows a basic refrigeration cycle configuration diagram for a refrigerator. In the refrigeration cycle apparatus including the refrigerant compressor 15, the condenser 16, the expansion mechanism 17, and the evaporator 18, the refrigerant compressor 15 sucks and compresses the low-temperature and low-pressure refrigerant gas, and discharges and condenses the high-temperature and high-pressure refrigerant gas. Send to vessel 16. The refrigerant gas sent to the condenser 16 becomes a high-temperature and high-pressure refrigerant liquid while releasing its heat into the air, and is sent to the expansion mechanism 17. The high-temperature and high-pressure refrigerant liquid passing through the expansion mechanism 17 becomes low-temperature and low-pressure wet steam due to the throttling effect and is sent to the evaporator 18. The refrigerant that has entered the evaporator 18 absorbs heat from the surroundings and evaporates, and the low-temperature and low-pressure refrigerant gas that has exited the evaporator 18 is sucked into the compressor 15, and the same cycle is repeated thereafter.

  In this refrigeration cycle configuration, a refrigerator or the like requires a low evaporator temperature (−40 ° C. or lower). Here, when refrigeration oil having poor compatibility with the refrigerant is used, the refrigeration oil separated from the refrigerant by the heat exchanger or the expansion mechanism is accumulated, and the oil return property to the compressor 15 is lowered.

  FIG. 3 shows a basic refrigeration cycle configuration diagram for an air conditioner. In the refrigeration apparatus including the refrigerant compressor 15, the condenser 16, the expansion mechanism 17, the evaporator 18, and the four-way valve 19, the refrigerant compressor 15 sucks and compresses the low-temperature and low-pressure refrigerant gas and discharges the high-temperature and high-pressure refrigerant gas. Then, it is sent to the four-way valve 19. The refrigerant sent here follows the refrigerant flow path in the four-way valve 19 and is sent here to the condenser. Accordingly, the refrigerant rotates counterclockwise as in FIG.

  The refrigerant gas sent to the condenser 16 becomes a high-temperature and high-pressure refrigerant liquid while releasing its heat into the air, and is sent to the expansion mechanism 17. The high-temperature and high-pressure refrigerant liquid passing through the expansion mechanism 17 becomes low-temperature and low-pressure wet steam due to the throttling effect and is sent to the evaporator 18. The refrigerant that has entered the evaporator 18 absorbs heat from the surroundings and evaporates, and the low-temperature and low-pressure refrigerant gas that has exited the evaporator 18 is sucked into the compressor 1, and the same cycle is repeated thereafter.

  By switching the four-way valve 19, the refrigerant flow path is changed, that is, the refrigerant turns clockwise as opposed to the above, so that the operation of the condenser 16 and the evaporator 18 is switched.

  In this refrigeration cycle, a room air conditioner or the like requires an intermediate evaporator temperature (−10 ° C. or lower). Here, when refrigeration oil having poor compatibility with the refrigerant is used, the refrigeration oil separated from the refrigerant by the heat exchanger or the expansion mechanism is accumulated, and the oil return property to the compressor 15 is lowered.

  The refrigerant used this time is hydrofluorocarbon-based and does not contain chlorine in the molecule. Therefore, the lubricity of the refrigerant itself cannot be expected, and the wear resistance of the compressor is lowered. By using the refrigerating machine oil, the lubricity of the refrigerant / refrigerating machine oil mixture can be ensured. As the above-mentioned polyol ester oil, a hindered type synthesized from a polyhydric alcohol and a monovalent fatty acid and excellent in thermal stability is preferable.

For example, as a polyhydric alcohol,
Pentaerythritol,
There is dipentaerythritol.

For example, as monovalent fatty acid,
Pentanoic acid,
Hexanoic acid,
Heptanoic acid,
Octanoic acid,
2-methylbutanoic acid,
2-methylpentanoic acid,
2-methylhexanoic acid,
2-ethylhexanoic acid,
Isooctanoic acid,
3,5,5-trimethylhexanoic acid and the like are used alone or in combination of two or more kinds.

  In particular, the base oil in the refrigerating machine oil is preferably at least one selected from the group of fatty acid ester oils represented by the formula (2), (3) or (4) having at least two ester bonds in the molecule.

[Chemical 2]
(R ¹ —CH ₂ ) ₂ —C— (CH ₂ —O—CO—R ² ) ₂ ... (2)
(Equation (2), R ¹ each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ² represents an alkyl group having 5 to 12 carbon atoms each independently)

[Chemical formula 3]
(R ¹ —CH ₂ ) —C— (CH ₂ —O—CO—R ² ) ₃ ... (3)
(In formula (3), R ¹ and R ² are as defined above.)

[Chemical formula 4]
C— (CH ₂ —O—CO—R ² ) ₄ ... (4)
(In formula (4), R ² is as defined above)
The viscosity of the refrigerating machine oil used in the refrigerating apparatus or the air conditioner shown in FIGS. 2 and 3 (measured according to JIS K 2283) varies depending on the type of the compressor, but in the scroll compressor, the viscosity at 40 ° C. is 40 to 100 mm ² / s. A range is preferred. When the viscosity is less than 40 mm ² / s, the viscosity of the refrigerating machine oil in which the refrigerant is dissolved becomes low, and the oil film inside the compressor is not sufficiently maintained, and the lubricity cannot be maintained. Furthermore, the sealing performance of the compression part cannot be maintained. On the other hand, when the viscosity exceeds 100 mm ² / s, mechanical loss such as viscous resistance and frictional resistance increases, and the compressor efficiency decreases.

  With respect to the acid scavenger having an alkyl glycidyl ester compound, if the addition amount is less than 0.1% by mass, a sufficient acid scavenging effect cannot be expected, and conversely if it exceeds 1% by mass, it may precipitate completely without being dissolved in the refrigerating machine oil. There is. Therefore, the addition amount is preferably 0.1 to 1.0% by mass.

  As for the organic insulating material used in the compressor motor, the heat insulation class of electrical insulation is defined by JEC-6147 (The Institute of Electrical Engineers of Japan, electrical standard survey standard). However, in the case of organic insulation materials for refrigeration and air-conditioning equipment, they are used in a special environment such as in a refrigerant atmosphere. Therefore, in addition to temperature, polar compounds such as refrigerant and refrigeration oil can be suppressed. Therefore, solvent resistance, extraction resistance, thermal / chemical / mechanical stability, and refrigerant resistance must be taken into consideration. The term “refrigerant resistance” as used herein refers to, for example, crazing (a fine bellows-like crack that occurs when the film is stressed and then immersed in the refrigerant), blister (the refrigerant absorbed in the film is caused by the temperature rise) Air bubbles). As an insulating material for an air conditioner, it is necessary to use an insulating material of a heat resistance class (B class 130 ° C. or higher).

  The insulating material most frequently used in the compressor is PET (polyethylene terephthalate). As a use, a film material is used for coil insulation with an iron core of a distributed winding motor, and fibrous PET is used for a coil binding thread and a covering material for a lead wire of a motor.

Other insulating films include
PPS (polyphenylene sulfide),
PEN (polyethylene naphthalate),
PEEK (polyether-terketone),
PI (polyimide),
PA (polyamide)
Etc.

In addition, the main insulation coating material of the coil
THEIC modified polyester,
polyamide,
Polyamideimide,
Polyesterimide,
Polyester amide imide or the like is used, and a double coated copper wire having a polyester imide-amide imide double coat is preferably used. In the embodiment of the present invention, there is no particular problem even if an antifoaming agent, a lubricity improver, an antioxidant, a metal deactivator or the like is added to the above-described refrigerator oil.

  As a method for confirming the acid scavenger performance of the refrigerating machine oil, thermal stability and hydrolyzability were evaluated by a shield tube test. The refrigerant is R410A, the refrigerating machine oil is polyol ester oil, and specifically, VG68 hindered ester oil composed of pentaerythritol as alcohol and i-C8 acid / i-C9 acid (50/50) as fatty acid is used. It was.

  Next, a shield tube test was performed as an organic insulating material evaluation in the compressor. The refrigerant is R410A, the refrigerating machine oil is polyol ester oil, and specifically, VG68 hindered ester oil composed of pentaerythritol as alcohol and i-C8 acid / i-C9 acid (50/50) as fatty acid is used. It was. As the insulating film, a heat-resistant grade (B type 130 ° C.) PET film was used, and as the enameled copper wire, a polyesterimide-polyamideimide double-coated wire was used.

  The evaluation items of the insulating material will be described. For the insulating film, the tensile strength retention and elongation retention before and after the test were measured. The target was a retention rate of 50% or more. In addition, the appearance change, pencil hardness change, winding characteristics, dielectric breakdown voltage (JIS C 3003) were measured for enameled copper wire, and crazing and blistering were observed for refrigerant resistance. For these items, the goal was to have no change before and after the test.

  Table 1 and FIG. 4 show the results of a shield tube test performed as a hydrolyzability evaluation. The refrigerating machine oil is a polyol ester oil. Specifically, hindered ester oil of VG68 composed of pentaerythritol as alcohol and i-C8 acid / i-C9 acid (50/50) as fatty acid was used. The shield tube test conditions were as follows: iron, copper, and aluminum with a length of 50 mm were placed in a glass tube having an inner diameter of 10φ, 5 g of refrigerating machine oil and 1 g of R410A as a refrigerant were sealed and sealed at 150 ° C. for a maximum of 14, 21, 28 After heating on the sun, the color of the oil, acid value, residual rate of additives, appearance of the catalyst, etc. were measured. The water content in the oil was 1000 ppm. As the types of acid scavengers, the alkyl glycidyl ester of this example (0.9 mass%) (1 formula) and the alicyclic epoxy compound (0.5 mass%) (5 formula) as Comparative Example 1 in order to make the epoxy equivalent. Was added respectively.

（但し、前記式中、Ｒは、独立して炭素数４〜１２のアルキル基を表す）

(However, in said formula, R represents a C4-C12 alkyl group independently.)

  The acid values and additives of the refrigeration oil after the test were measured according to JIS K2501 “Petroleum products and lubricants—neutralization number test method”. The hue was in accordance with JIS K2580 “Petroleum product color test method”. The residual rate of the additive was determined by a method according to JIS K2501 “Petroleum products and lubricants—neutralization number test method”.

  As a result of the evaluation, when the water content was 1000 ppm, no increase in acid value was observed even when heated for 28 days in the case of Example 1, but in the case of Comparative Example 1, the acid was increased to 0.05 mgKOH / g when heated for 28 days. An increase in value was observed.

  When the residual ratio of the acid scavenger was measured, in Comparative Example 1, the acid value increased to 0.05 mgKOH / g despite the fact that 47% of the acid scavenger remained. From this, it can be seen that the reaction rate of acid capture does not catch up with the acid generation rate. There is a concern that the generated acid reacts with corrosion of the sliding part or metal to generate metal soap, which may clog the valve and cause malfunction.

  The shield tube test performed as the hydrolyzability evaluation in the same manner as in Example 1 was performed by changing the conditions. The evaluation results are shown in Table 2 and FIG. The refrigerating machine oil is a polyol ester oil. Specifically, hindered ester oil of VG68 composed of pentaerythritol as alcohol and i-C8 acid / i-C9 acid (50/50) as fatty acid was used. Shield tube test conditions were as follows: iron, copper, aluminum with a length of 50 mm as a catalyst in a glass tube with an inner diameter of 10φ, 5 g of refrigerating machine oil and 1 g of R410A as a refrigerant, sealed, and heated at 150 ° C. for a maximum of 20, 40 days Thereafter, oil color, acid value, additive residual ratio, appearance of the catalyst, and the like were measured. The water content in the oil was 2000 ppm.

  As a result of the evaluation, when the water content was 2000 ppm, the refrigerating machine oil of Example 2 to which the alkyl glycidyl ester was added did not increase the acid value when heated for 20 days, and remained slightly changed to 0.03 mg KOH / g even when heated for 40 days. However, Comparative Example 2 to which an alicyclic epoxy compound was added started to increase to 0.04 mg KOH / g at the time of heating on the 20th, and 1.13 mgKOH / g in the product heated at the 40th day. An increase was observed.

  However, when the residual ratio of the acid scavenger was measured, the residual ratio of the acid scavenger was as high as 67% in the comparative example 2, and it was found that the reaction rate of the acid scavenger could not catch up with the fatty acid production rate.

  Table 3 shows the results of a shield tube test conducted as an oil resistance / refrigerant evaluation of the insulating film. As the refrigerating machine oil, VG68 polyol ester oil was used. Shield tube test conditions include a glass tube having an inner diameter of 10φ and an insulating material processed into a dumbbell shape having a length of 50 mm and a width of 3 mm as a test sample, polyol ester oil as a refrigerating machine oil, specifically as alcohol After injecting pentaerythritol, 5 g of hindered ester oil of VG68 consisting of i-C8 acid / i-C9 acid (50/50) as fatty acid and 0.5 g of R410A as refrigerant, sealed and heated at 130 ° C. for up to 40 days The oil color, acid value, appearance of the specimen, strength, etc. were measured. The water content in the oil was 50 ppm. Alkyl glycidyl ester (0.9 mass%) was added as the type of acid scavenger.

  The acid value of the refrigerating machine oil after the test was in accordance with JIS K2501 “Petroleum products and lubricating oils—Neutralization number test method”. The hue was in accordance with JIS K2580 “Petroleum product color test method”. The tensile strength of the insulating material was measured by a method according to JIS C2111 “Electrical insulating paper test method”.

  As a result of the evaluation, no deterioration of the refrigerating machine oil was recognized in terms of hue, acid value and the like. It was confirmed that there were no abnormalities in the appearance, tensile strength, flexibility, etc. of the insulating film material.

  This test method is an accelerated test, and it is worth more than 10 years when converted into actual operating years. Since this is equivalent to the conventional product, that is, it is considered that there is no influence even if the conventional one and the embodiment are replaced.

  Table 4 shows the results of a shield tube test performed as an oil resistance / refrigerant evaluation of enameled wire. The refrigerating machine oil is a polyol ester oil. Specifically, hindered ester oil of VG68 composed of pentaerythritol as alcohol and i-C8 acid / i-C9 acid (50/50) as fatty acid was used. The shield tube test conditions were as follows: a twisted pair with a length of 18 cm and a 10 cm enamel wire were put into a glass tube with an inner diameter of 10φ, and 5 g of polyol ester oil as a refrigerating machine oil and 0.5 g of R410A as a refrigerant were injected. After sealing and heating at 150 ° C. for a maximum of 40 days, the oil color, acid value, appearance of the specimen, film strength, etc. were measured. The water content in the oil was 50 ppm. Alkyl glycidyl ester (0.9 mass%) was added as the type of acid scavenger.

  The acid value of the refrigerating machine oil after the test was in accordance with JIS K2501 “Petroleum products and lubricating oils—Neutralization number test method”. The hue was in accordance with JIS K2580 “Petroleum product color test method”. The enameled wire was evaluated by a method according to JIS C3003 “Enameled wire test method” and JIS C3202 “Enameled wire”. As a result of the evaluation, no deterioration of the refrigerating machine oil was observed. Further, the enameled copper wire was good because the pencil hardness was 5H and the winding characteristic was not wound on the film even when wound around its own diameter. The breakdown voltage was almost the same as the initial value, and it was confirmed from the appearance that no crazing or blistering occurred, and the target was satisfied.

  This test method is an accelerated test, and it is worth more than 10 years when converted into actual operating years.

  Since this is equivalent to the conventional product, that is, it is considered that there is no influence even if the conventional one and the embodiment are replaced.

  A 90-day actual machine evaluation test was carried out on a room air conditioner equipped with a scroll compressor containing a polyol ester oil added with an alkyl glycidyl ester compound as an acid scavenger. 1600 g of R410A as a refrigerant, a refrigerating machine oil is a polyol ester oil, specifically, 460 ml of hindered ester oil of VG68 consisting of pentaerythritol as alcohol and i-C8 acid / i-C9 acid (50/50) as fatty acid. Enclosed. As an acid scavenger, 0.9% by mass of the alkyl glycidyl ester of the present invention was added. When the refrigerating machine oil after the refrigerating machine oil test was analyzed, it was confirmed that there was no increase in the acid value and 50% or more of the additive remained. No abnormality was found in the motor insulation material.

  The present invention relates to a compressor using a hydrofluorocarbon (HFC) refrigerant, and can also be applied to a refrigeration apparatus and an air conditioner equipped with the compressor.

It is sectional drawing explaining a hermetic refrigerant compressor. It is a refrigeration cycle block diagram for basic refrigerators. It is a refrigeration cycle block diagram for basic air conditioners. It is a hydrolyzability test result when 1000 ppm of moisture is added. It is a hydrolyzability test result when water is added at 2000 ppm.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Case 2 Compressor part 3 Electric motor 4 Orbiting scroll 5 Fixed scroll 6 Frame 7 Crankshaft 8 Oldham ring 9 Intake pipe 10 Rotor 11 Stator 12 Eccentric part 13 Shaft hole 14 Refrigerating machine oil 14a Acid scavenger 15 Compressor 16 Condenser 17 Expansion mechanism 18 Evaporator 19 Four-way valve

Claims (5)

A motor having a rotor and a stator in an airtight container for storing refrigerating machine oil;
A rotating shaft fitted to the rotor;
In the refrigerant compressor that houses the compression unit connected to the motor via the rotating shaft,
The refrigerant sealed in the refrigerant compressor is R410A, R407C or R404A,
A refrigerant compressor using a refrigerating machine oil containing a polyol ester oil as a base oil and an alkyl glycidyl ester compound as an acid scavenger. At least in a refrigeration cycle apparatus configured with a compressor, a condenser, an expansion mechanism, an evaporator and a refrigerant pipe connecting them,
A refrigeration cycle apparatus, wherein the compressor is the refrigerant compressor according to claim 1. In claim 2,
The alkyl glycidyl ester compound has a structure represented by the following formula (1).

(However, in said formula, R represents a C4-C12 alkyl group independently.) In claim 2,
A refrigeration cycle apparatus comprising 0.1 to 1.0% by mass of the alkyl glycidyl ester compound. In claim 1,
An organic material used for the refrigerant compressor is a material that is not physically and chemically deteriorated.

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