JP2000129275A - Working fluid composition for refrigerating/air- conditioning machine and refrigerating/air-conditioning apparatus using same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a working fluid composition which can prevent the viscosity decrease of a refrigerant/refrigerator oil mixture and the lubrication defects of a compressor by incorporating a refrigerant comprising propane and/or isobutane together with a polyalkylene glycol into the same. SOLUTION: The polyalkylene glycol is represented by formula I (wherein R1 is H or 1-4C alkyl; R3 to R6 are each H or CH3; X is 2-4C oxyalkylene; and (m), (n), (p), and (q) are each 1-30 provided when X is not present, then (p) and (q) are both 0). Preferably, 0.05-5.0 wt.% phosphorus compound represented by formula II or 0.05-5.0 wt.% cyclic carbonate compound represented by formula III is added to the polyalkylene glycol. In these formulas, R7 is 4-18C alkyl, oleyl, phenyl, or o-, m-, or p-tolyl; and R8 is H, or 1-4C (perfluoro)alkyl. In addition, the composition can improve the pull down (cool down) properties of a refrigerating/air-conditioning apparatus.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerant compression working medium for a refrigerator / air conditioner, and more particularly to a refrigerator / air conditioner using a refrigerant compressor for a refrigerator or a room air conditioner.

[0002]

2. Description of the Related Art Conventionally, CFC (chlorofluorocarbon) and HCFC (hydrofluorocarbon) used in refrigerators and air conditioners have been completely eliminated from the viewpoint of protection of the ozone layer. A possible alternative refrigerant is HFC, which does not contain chlorine in the molecule and does not destroy the ozone layer.
(Hydrofluorocarbon) -based refrigerants. For example CF
HFC32 with thermodynamic properties similar to C12 (dichlorodifluoromethane) and HCFC22 (monochlorodifluoromethane)
(Difluoromethane), HFC125 (pentafluoroethane) and HFC134a (1,1,1,2-tetrafluoroethane) alone or as a mixture of at least two HFC non-azeotropic mixed refrigerants and HFC pseudo-azeotropic mixed refrigerants Are listed.

[0003] However, although these HFCs do not contribute to ozone layer depletion, regulations on HFCs are also in the direction of progress from the viewpoint of preventing global warming. Refrigerators that use hydrocarbon-based refrigerants with low global warming potential, so-called natural refrigerants, have been commercialized as alternative refrigerants to CFCs (chlorofluorocarbons) and HCFCs (hydrofluorocarbons) in Europe, which is highly concerned with environmental issues. Refrigeration and air conditioning systems using refrigerants such as propane and isobutane are also being developed in Japan.

[0004] Refrigeration oil is used in compressors for refrigeration and air conditioners such as room air conditioners and package air conditioners, and plays a role in lubrication, sealing, cooling and the like of sliding parts thereof.

[0005] In recent years, compressors have been
Low noise and high efficiency are required, and the use conditions of refrigeration oil are becoming severer. For this reason, a refrigerating machine oil excellent in lubricity, especially in abrasion resistance is required from the viewpoint of securing the reliability of the compressor.

As refrigeration oils, naphthenic and paraffinic mineral oils and alkylbenzenes have been widely used because of their good compatibility with CFC (chlorofluorocarbon) and HCFC (hydrochlorofluorocarbon) refrigerants and their low cost.

Refrigerants such as propane and isobutane have too high a solubility in these refrigerating machine oils, and there is a concern that poor lubrication of the compressor occurs due to a decrease in viscosity of the refrigerant / oil mixture. Also,
Since the solubility is high, there is a problem that characteristics such as pull-down (cool-down) are inferior to the system in which the amount of the refrigerant is charged, as compared with a system that is hardly soluble.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above,
By using polyalkylene glycol, which is hardly soluble in hydrocarbon-based refrigerants, propane and isobutane, the viscosity of the refrigerant / oil mixture is suppressed from lowering, and the characteristics such as pull-down (cool-down) are higher than those of highly soluble oil. Excellent refrigeration
An object of the present invention is to provide a working medium composition for an air conditioner.

[0009] Further, by blending a phosphorus compound or a cyclic carbonate compound with the polyalkylene glycol, the lubricity can be greatly improved. The working medium composition for refrigeration / air-conditioning machines, which can supply oil from the oil reservoir even when separated in the compressor due to the density difference between the hydrocarbon-based refrigerant and polyalkylene glycol, greatly improving the reliability of the compressor An object and a refrigeration / air conditioner are provided.

[0010]

The gist of the present invention is as follows.

[1] (A) one of propane and isobutane;
Or a refrigerant comprising a mixture thereof, and (B) the following general formula (1)

[0012]

Embedded image

(Wherein, R1 and R2 each represent hydrogen or an alkyl group having 1 to 4 carbon atoms, which may be the same or different. R3 to R6 each represent hydrogen or a methyl group, and X represents an oxyalkylene group having 2 to 4 carbon atoms, and m, n, p, and q each represent a number of 1 to 30. However, when X does not exist, p represents
And q are 0. A working fluid composition for a refrigerator / air conditioner, comprising a polyalkylene glycol represented by the formula (1).

[2] The polyalkylene glycol of the above item [1] has the following general formula (2)

[0015]

Embedded image

(Wherein R7 represents an alkyl group having 4 to 18 carbon atoms or oleyl group, or a phenyl group or o-, m-
-,-Represents a tolyl group. A) a phosphorus compound represented by
Or the following general formula (3)

[0017]

Embedded image

(Wherein, R8 and R9 each independently represent hydrogen, fluorine, an alkyl group having 1 to 4 carbon atoms, or a perfluoroalkyl group having 1 to 4 carbon atoms.
R9 may be the same or different. A) a working medium composition for a refrigerator / air conditioner, comprising 0.05% by weight to 5.0% by weight of any of the cyclic carbonate compounds represented by the formula (1).

[3] (A) one of propane and isobutane
Alternatively, a working medium composition for a refrigerating / air-conditioning machine, comprising: a refrigerant comprising a mixture thereof; and (B) a compound having a low-temperature-side critical melting temperature of −40 ° C. or higher.

[4] The above item [1] wherein the component (B) is at least one of a polyisopropylene glycol methyl ethyl ether compound and a methyl ethyl ether compound of a polyisopropylene glycol / polyethylene glycol copolymer. Or the working medium composition for a refrigerator / air conditioner according to the item [3].

[5] In a refrigeration / air-conditioning apparatus provided with a refrigeration cycle for circulating a refrigerant gas discharged from a compressor having a working medium for a refrigeration / air-conditioner through a condensing means, an expansion means, and an evaporating means, The working medium for the air conditioner comprises (A) a refrigerant comprising one of propane and isobutane or a mixture thereof, and (B) a general formula (1)

[0022]

Embedded image

(Wherein, R 1 and R 2 each represent hydrogen or an alkyl group having 1 to 4 carbon atoms, which may be the same or different. R 3 to R 6 each represent hydrogen or a methyl group, and X represents an oxyalkylene group having 2 to 4 carbon atoms, and m, n, p, and q each represent a number of 1 to 30. However, when X does not exist, p represents
And q are 0. And a polyalkylene glycol represented by the formula (1).

[6] The polyalkylene glycol as described in the above item [5] has the following general formula (2)

[0025]

Embedded image

(Wherein R7 represents an alkyl group having 4 to 18 carbon atoms or oleyl group, or a phenyl group or o-, m-
-,-Represents a tolyl group. ) Or the following general formula (3)

[0027]

Embedded image

(Wherein R8 and R9 each independently represent hydrogen, fluorine, an alkyl group having 1 to 4 carbon atoms, or a perfluoroalkyl group having 1 to 4 carbon atoms.
R9 may be the same or different. A refrigeration / air-conditioning apparatus comprising 0.05 to 5.0% by weight of the cyclic carbonate compound represented by the formula (1).

[7] In a refrigeration / air-conditioning apparatus provided with a refrigeration cycle for circulating a refrigerant gas discharged from a compressor having a working medium for a refrigeration / air-conditioner through a condensing means, an expansion means, and an evaporating means, The working medium for an air conditioner contains (A) a refrigerant composed of one of propane and isobutane or a mixture thereof, and (B) a compound having a lower critical melting temperature (UCST) of -40 ° C or higher. A refrigeration / air conditioner characterized by the following.

[8] Component (B) is at least one of a polyisopropylene glycol methyl ethyl ether compound or a methyl ethyl ether compound of a polyisopropylene glycol / polyethylene glycol copolymer.
The refrigeration / air-conditioning apparatus according to the above [6] or [7], which is a seed.

In the present invention, examples of the hydrocarbon-based refrigerant which is a constituent component of the working medium for the refrigerator / air conditioner include propane, isobutane, or a mixture thereof. As compared with HCFC22 containing chlorine in the molecule, these cannot expect the lubricity of the refrigerant itself, and the sliding conditions of the compressor become severe.

On the other hand, the polyalkylene glycol of the refrigerator oil includes polyethylene glycol, polyisopropylene glycol, polyethylene glycol-polyisopropylene glycol copolymer, polyisopropylene glycol monobutyl ether, polyethylene glycol.
Polyisopropylene glycol copolymer monobutyl ether, polyethylene glycol dimethyl ether, polyethylene glycol diethyl ether, polyethylene glycol dipropyl ether, polyethylene glycol dibutyl ether, polyethylene glycol methyl ethyl ether, polyethylene glycol methyl propyl ether, polyethylene glycol methyl butyl ether, polyethylene Glycol ethyl propyl ether,
Polyethylene glycol ethyl butyl ether, polyethylene glycol propyl butyl ether, polyisopropylene glycol dimethyl ether, polyisopropylene glycol diethyl ether, polyisopropylene glycol dipropyl ether, polyisopropylene glycol dibutyl ether, polyisopropylene glycol methyl ethyl ether, polyisopropylene glycol Methyl propyl ether, polyisopropylene glycol methyl butyl ether, polyisopropylene glycol ethyl propyl ether, polyisopropylene glycol ethyl butyl ether, polyisopropylene glycol propyl butyl ether, (A) 1,2-bis (methoxypolyethyleneoxy) ethylene, 1, 2-bis (methoxypolyethylene B) Propylene, 1,2-bis (methoxypolyethyleneoxy) butylene, 1,2-bis (ethoxypolyethyleneoxy) ethylene, 1,2-bis (ethoxyethyleneoxy) propylene, 1,2-bis (ethoxypolyethyleneoxy) Butylene, 1,2-bis (propoxypolyethyleneoxy) ethylene, 1,2-bis (propoxypolyethyleneoxy) propylene, 1,2-bis (propoxypolyethyleneoxy) butylene, 1,2-bis (butoxypolyethyleneoxy) ethylene, 1,2-bis (butoxypolyethyleneoxy) propylene, 1,2-bis (butoxypolyethyleneoxy) butylene 1,2-bis (methoxypolyisopropyleneoxy) ethylene, 1,2-bis (methoxypolyisopropyleneoxy) propylene , 1,2-bis (methoxypolyisopropyleneoxy) butylene, 1,2-bis (ethoxy Li isopropylene-oxy) ethylene, 1,2-bis (ethoxy poly isopropylene oxy) propylene, 1,
2-bis (ethoxypolyisopropyleneoxy) butylene, 1,2-bis (propoxypolyisopropyleneoxy)
Ethylene, 1,2-bis (propoxypolyisopropyleneoxy) propylene, 1,2-bis (propoxypolyisopropyleneoxy) butylene, 1,2-bis (butoxypolyisopropyleneoxy) ethylene, 1,2-bis ( Butoxypolyisopropyleneoxy) propylene, 1,2-bis (butoxypolyisopropyleneoxy) butylene and the like. The viscosity grade of the polyalkylene glycol varies depending on the type of the compressor, but the viscosity at 40 ° C. is preferably in the range of 7 to 60 mm 2 / s.

Phosphorus compounds which are additives for improving lubricity include tributyl phosphate, tripentyl phosphate, trihexyl phosphate, triheptyl phosphate, trioctyl phosphate, trinonyl phosphate, tridecyl phosphate, trilauryl phosphate, tristearyl. Phosphate, triphenyl phosphate, tricresyl phosphate and the like can be mentioned. As the cyclic carbonate compound, ethylene carbonate, 3-methyl-ethylene carbonate, 3-
Ethyl-ethylene carbonate, 3-propyl-ethylene carbonate, 3-butyl-ethylene carbonate,
3,4-methyl-ethylene carbonate, 3-ethyl-4-
Methyl-ethylene carbonate, 3-propyl-4-methyl-ethylene carbonate, 3-butyl-4-methyl-ethylene carbonate, 3,4-ethyl-ethylene carbonate, 3-propyl-4-ethyl-ethylene carbonate, 3-butyl -4-ethyl-ethylene carbonate, 3,
4-propyl-ethylene carbonate, 3-butyl-4-
Propyl-ethylene carbonate and the like.

Examples of the cyclic carbonate compound in which a part of the cyclic carbonate compound is substituted with fluorine include 3-fluoro-ethylene carbonate, 3,4-fluoro-ethylene carbonate, 3-trifluoromethyl-ethylene carbonate,
-Pentafluoroethyl-ethylene carbonate, 3,4
-Trifluoromethyl-ethylene carbonate, 3-fluoroethyl-4-fluoromethyl-ethylene carbonate and the like.

The compounding ratio of the phosphorus compound and the cyclic carbonate compound, which are additives for improving the lubricity, is 0.05% by weight to 5.0% by weight with respect to the aforementioned refrigerating machine oil, and 0.1 to 1.0% by weight. Is more preferable. If the compounding ratio of the phosphorus compound and the cyclic carbonate compound is less than 0.05% by weight, sufficient lubricity cannot be obtained.

On the other hand, when the compounding ratio of the phosphorus compound and the cyclic carbonate compound exceeds 5.0% by weight, the compound does not completely dissolve in the refrigerating machine oil and causes a clogging phenomenon of the refrigerating cycle. In the present invention, an antioxidant, an acid scavenger, an antifoaming agent, a metal deactivator, and the like may be added to the working medium composition.

In the present invention, by using a refrigerant consisting of propane, isobutane or a mixture thereof and a polyalkylene glycol having low solubility, it is possible to suppress a decrease in the viscosity of the refrigerant / oil mixture and to reduce pull-down (cool down) and the like. Performance is improved.

Further, by blending a phosphorus compound or a cyclic carbonate compound with the polyalkylene glycol, the lubricity can be greatly improved.

[0039]

BEST MODE FOR CARRYING OUT THE INVENTION Refrigerating compressors for refrigerators and refrigerators / air conditioners include scroll, reciprocating, screw, rotary type isometric displacement compressors and turbo type displacement compressors. FIG. 1 shows a schematic structure of a scroll compressor as an example of the compression means.

As shown in FIG. 1, the compressor comprises a spiral wrap 5 standing upright on the end plate 3 of the fixed scroll member 1, an end plate 4 and a wrap 6 having substantially the same shape as the fixed scroll member 1.
The orbiting scroll member 2 is formed by engaging the wrap 5 and the wrap 6 with the wrap 5 facing each other to form a compression mechanism, and the orbiting scroll member 2 is caused to orbit by the crankshaft 7. The compression chamber 8 (8a, 8b ...) formed by the fixed scroll member 1 and the orbiting scroll member 2
…)), The outermost compression chamber moves toward the center of both scroll members 1 and 2 while the volume gradually decreases with the orbital movement.

When the compression chambers 8a and 8b reach the vicinity of the centers of the scroll members 1 and 2, the compression chambers 8a and 8b communicate with the discharge port 9 to discharge the compressed gas in the compression chambers. The gas passes through the scroll member 1 and a gas passage (not shown) provided in the frame 10 to reach the inside of the compression container 11 at the lower portion of the frame, and is discharged from the compressor through a discharge pipe 12 provided on a side wall of the compression container 11. You.

In this compressor, an electric motor is
The compressor 13 performs a compression operation by rotating the crankshaft 7 at a constant speed or at a rotation speed according to a voltage controlled by an inverter (not shown). Further, an oil reservoir is provided at a lower portion of the motor 13,
The oil passes through an oil hole 14 provided in the crankshaft due to a pressure difference, and is used for lubrication of a sliding portion between the orbiting scroll member 2 and the crankshaft 7, a sliding bearing 16, and the like.

Next, the refrigeration cycle will be described. Fig. 2 shows a configuration diagram of a heat pump refrigeration cycle for a room air conditioner and a package air conditioner that also serves as cooling and heating.

In order to cool the room, high-temperature and high-pressure refrigerant gas which is adiabatically compressed from the discharge pipe of the compressor 18 is supplied to the four-way valve.
Outdoor heat exchanger 20 through 19 (used as condensation means)
And becomes a high-pressure liquid refrigerant. This refrigerant is expansion means
21 (for example, a capillary tube or a thermal expansion valve, etc.), and becomes a low-temperature low-pressure liquid containing a slight amount of gas, and reaches an indoor heat exchanger 22 (used as an evaporating means).
The four-way valve 19 is obtained again in the state of low-temperature gas by obtaining heat from indoor air.
Through the compressor 18. When heating the room, the flow of the refrigerant is changed in the opposite direction by the four-way valve 19, and the operation is reversed.

Now, the present invention will be described in further detail with reference to Examples.

[0046]

(Examples 1 to 30) and

[Comparative Examples 1 to 4] In Examples 1 to 9, the compatibility of propane and isobutane, which are hydrocarbon refrigerants, and a refrigerant obtained by mixing 50/50 thereof with a typical polyalkylene glycol was determined by JI.
It was evaluated according to S K2211. Comparative Examples 1 and 2 used conventionally used alkylbenzenes and naphthenic mineral oils, and Comparative Examples 3 and 4 used polyol esters, polyvinyl ethers and various hydrocarbon-based refrigerants described above as HFC-based refrigerants. Was evaluated for compatibility. Table 1 shows the results.

[0047]

[Table 1]

Here, UCST (Uppermost Critical Solubil)
ity Temperature (lower temperature critical melting temperature) is the highest temperature at which layer separation occurs in the entire composition ratio range of refrigerant / refrigeration oil, and a high UCST indicates that refrigerant solubility of refrigerant oil is low. . As is clear from the table, the working medium composition for a refrigerator / air conditioner of the present invention has higher UCST with propane, isobutane and a mixed refrigerant thereof as compared with Comparative Examples 1 to 4,
It can be seen that the solubility in these refrigerants is low.

[0049]

Examples 31 to 60; and

Comparative Example 5 Next, the lubricity of the polyalkylene glycol which was confirmed to have low solubility in the hydrocarbon-based refrigerant in the above example was evaluated. Examples 31 to 60 show the results evaluated by the Falex test.

In Comparative Example 5, a conventionally used alkylbenzene was taken as a comparison. The method of the Falex test is as follows. A rotating shaft (pin) with a diameter of about 6 mm is symmetrically sandwiched between two V blocks from left and right, and immersed in refrigerator oil filled in an oil cup. In the abrasion test, operation was performed for 5 hours at a load of 100 lb, oil temperature of 100 ° C, and rotation speed of 290 rpm, and the total wear depth of the pin and V block was calculated from the load-corrected scale change of the ratchet, which is the load mechanism of the Falex testing machine. The obtained value was defined as the amount of wear.

While heating from room temperature to 100 ° C., 50 l
The driver ran for 10 minutes at b. 50l in baking test
After a running-in operation for 5 minutes at b, the ratchet gear was rotated to continuously increase the load, and the load at which the frictional force suddenly increased due to seizure was recorded as the seizure load. Table 2 shows the results of the Falex test.

[0052]

[Table 2]

As is clear from Table 2, the base oil of the refrigerating machine oil composition of the present invention, even when used alone, has a smaller amount of abrasion than the alkylbenzene shown in Comparative Example 5, and has a high seizure load and excellent lubricity. You can see that.

[0054]

Examples 61 to 71 Next, using polyisopropylene glycol methyl ethyl ether which was excellent in lubricity in Example 16, the phosphorus compound and the cyclic carbonate compound were added in an amount of 0.5% by weight.
The same Falex test as in Examples 31 to 60 was performed by adding and changing the type of the additive. Table 3 shows the results of Examples 61 to 71.

[0055]

[Table 3]

As can be seen from Table 3, the working medium composition for a refrigeration / air conditioner of the present invention shows that the lubricating property of the base oil alone of Example 16 is lower than that of the base oil by 0.5% of the phosphorus compound and the cyclic carbonate compound. By adding the weight%, the lubricity is further improved.

[0057]

Examples 72 to 79; and

Comparative Examples 6 to 9 Next, using polyisopropylene glycol methyl ethyl ether which was excellent in lubricity in Example 16, tricresyl phosphate as a phosphorus compound and 3-trifluoromethyl ethylene carbonate as a cyclic carbonate compound were used. Add, change the amount of additives,
The same Falex test as in Examples 31 to 60 was performed. Table 4
Shows the results of Examples 72 to 79 and Comparative Examples 6 to 9.

[0058]

[Table 4]

As can be seen from Table 4, the working medium composition for a refrigerating machine / air conditioner of the present invention shows that the lubricating property of the base oil alone of Example 16 is lower than that of the base oil by 0.05% for the phosphorus compound and the cyclic carbonate compound. Addition of not less than% by weight significantly improves lubricity.

As shown in Comparative Examples 6 and 7, when the phosphorus compound and the cyclic carbonate compound were added in an amount of 0.01% by weight to the base oil, sufficient lubricity was not obtained. There is no. In addition, as shown in Comparative Examples 8 and 9, those added at 10% by weight did not completely dissolve in the refrigerating machine oil, so that the test was not performed.

[0061]

Examples 80 to 109; and

Comparative Examples 10 to 13 In a refrigeration cycle in which an actual scroll compressor was incorporated, the working medium composition for a refrigerator / air conditioner of the present invention was sealed, and an actual machine test was conducted under heat load and operating time. In this scroll compressor, the amount of increase in gap due to wear between the frame and the shaft before and after the test was measured because the friction condition between the frame and the shaft was severe.

In Examples 80 to 109, propane was used as the refrigerant, and as the refrigerating machine oil, various polyalkylene glycols which were confirmed to have low solubility with the hydrocarbon-based refrigerant in Examples 1 to 30 were used. In Example 101, a similar test was performed using isobutane and a mixed refrigerant of propane / isobutane as the refrigerant. For comparison, alkylbenzene, naphthenic mineral oil, polyol ester, and polyvinyl ether, which are refrigerating machine oils which were confirmed to be completely dissolved in the hydrocarbon-based refrigerant in Comparative Examples 1 to 4 in Comparative Examples 10 to 13, were taken up. Table 5 shows the results
Shown in

[0063]

[Table 5]

The greater the increase in the gap between the frame and the shaft, the greater the amount of wear.

As is evident from Table 5, the refrigeration of the present invention
The working medium composition for air conditioners is significantly less flame-intensive than systems using refrigeration oil that completely dissolves hydrocarbon-based refrigerants.
It was found that the amount of increase in the gap between the shafts could be reduced and excellent wear resistance was exhibited. This is because the viscosity when propane / polyalkylene glycol is dissolved is higher than the propane dissolved viscosity of alkylbenzene, and the absolute amount of oil supplied to the sliding portion is large.

Further, it can be seen from Examples 101 and 107 that similar results can be obtained by using any of propane, isobutane, and a mixed refrigerant of propane / isobutane. On the other hand, in a system using a refrigerating machine oil that completely dissolves with a hydrocarbon-based refrigerant, the solubility of each other is too high, and a large amount of propane, which does not have a lubricating effect, is supplied to the sliding portion of the compressor. Is not obtained.

[0067]

Examples 110 to 124; and

Comparative Examples 14 to 17 In the above-mentioned refrigeration cycle, the working medium composition for a refrigeration / air conditioner of the present invention was sealed, and
An actual machine test was performed at a fixed time. In Examples 110 to 124, propane was used as the refrigerant, and polyisopropylene glycol methyl ethyl ether was used as the refrigerating machine oil. In Examples 61 to 71, the various phosphorus compounds and the cyclic carbonate compounds having the effect of improving the lubricity were obtained by using the refrigerating machine oil. 0.5% by weight
The additions were tested. For tricresyl phosphate and 3-trifluoromethylethylene carbonate, the amount of addition was changed from 0.05% by weight to 5.0% by weight. In Comparative Examples 14 to 17, tricresyl phosphate and 3-
The amount of trifluoromethylethylene carbonate added was set to 0.
Similar tests were performed with 01% by weight and 10% by weight. Table 6 shows the results.

[0068]

[Table 6]

As is evident from Table 6, the refrigeration of the present invention
It can be seen that the composition in which the phosphorus compound and the cyclic carbonate compound are blended as additives in the working medium composition for an air conditioner can obtain better lubricity as compared with Example 101 in which no additive is added. It is considered that this is because phosphorus compounds and cyclic carbonate compounds are effectively adsorbed on the sliding surface of polyalkylene glycol having a small polarity, and a reaction film is easily formed.

Examples 114 to 117 and Examples 121 to 124
As shown in the above, these additives are
A sufficient effect is exhibited by adding 0.05% by weight to 5.0% by weight. The effects of improving lubricity can be obtained by using any of the hydrocarbon refrigerants according to Examples 115 and 122. On the other hand, as shown in Comparative Examples 14 and 15, when the addition amount was 0.01% by weight, a sufficient effect of suppressing the amount of wear was not obtained, and when the addition amount shown in Comparative Examples 16 and 17 was 10% by weight, Since it did not completely dissolve in the refrigerating machine oil, the test was not performed in consideration of the blockage of the refrigerating cycle.

[0071]

Embodiment 125 and

Comparative Example 18 In Example 125, the pull-down (cool-down) characteristics of a refrigerator using isobutane and polyisopropylene glycol methyl ethyl ether as a polyalkylene glycol as a working medium were measured. In the evaluation method, the motor in the compressor was rotated at full speed, and the performance was tested for a required time from the room temperature to -30 ° C in the freezer. The amount of refrigerant charged was 70 g, and the amount of refrigerating machine oil was 250 g. Comparative Example 1
In Example 8, a performance evaluation test similar to that of Example 125 was performed using the same amount of alkylbenzene that completely dissolves in isobutane. The target arrival time of the isobutane / alkylbenzene system was set to 1. Table 7 shows the results.

[0072]

[Table 7]

As is clear from Table 7, the working medium composition for an air conditioner of the present invention has a target reaching time which is about 20% faster than that of an isobutane / alkylbenzene system, and a solubility in a hydrocarbon-based refrigerant. It was confirmed that the pull-down (cool-down) characteristics were improved by using a polyalkylene glycol having a small value.

Although Table 3, Table 4, Table 6, and Table 7 mainly describe only polyisopropylene glycol methyl ethyl ether, as can be seen from Tables 1, 2, and 5, other alkylene glycols are used. Has exactly the same effect. The viscosity grade of the polyalkylene glycol is determined in consideration of the type of the compressor. In other words, the minimum viscosity (viscosity when the refrigerant is dissolved) required to maintain the reliability or efficiency of the compressor is 1 in the reciprocating type.
22 mm2 / s, scroll type: 2-3 mm2 / s, rotary type: 3-5 mm2 / s, screw type: 20-30 mm2 / s from the sealing surface of the blowhole. Therefore, the viscosity grade of the refrigerating machine oil is determined by the type of the compressor used in the air conditioner, and the molecular weight of the formula (1), that is, R1 to R6
And X, and m, n, p, and q are determined. However, this is a design issue and is not addressed in the present invention.

From the above results, the refrigerant composed of propane and isobutane alone or a mixture thereof and the working medium composition for refrigeration / air conditioner containing polyalkylene glycol have low solubility in each other. It was confirmed that the decrease in viscosity of the machine oil mixture was small, and the addition of a phosphorus compound or a cyclic carbonate compound further improved lubricity.

In a refrigerating / air-conditioning apparatus using the composition, a substance having a high viscosity and an absolutely high oil concentration is supplied to the sliding portion due to low solubility, so that poor lubrication of the compressor does not occur. And improved long-term reliability. Further, a refrigeration / air-conditioning apparatus having improved pull-down (cool-down) characteristics by using the composition was obtained.

[0077]

The present invention uses a refrigerant composed of propane or isobutane alone or a mixture thereof and a polyalkylene glycol as a working medium composition for a refrigeration / air conditioner. It has the effect of preventing the viscosity of the machine oil mixture from lowering. Furthermore, by blending a phosphorus compound or a cyclic carbonate compound in the range of 0.05% by weight to 5.0% by weight with respect to the polyalkylene glycol, it is a working medium for refrigerating / air-conditioning equipment in which additives are completely dissolved, and at the same time, greatly improves lubricity. There is an effect that can be improved.

The refrigeration / air-conditioning apparatus of the present invention uses a working medium composition containing a refrigerant comprising propane or isobutane alone or a mixture thereof, and a polyalkylene glycol to obtain a refrigerant / refrigeration oil mixture. It has the effect of preventing a decrease in viscosity and preventing poor lubrication of the compressor.

Further, by blending a phosphorus compound or a cyclic carbonate compound in the range of 0.05% by weight to 5.0% by weight with respect to the polyalkylene glycol, a freezing cycle having a long-term reliability without causing blockage in a refrigeration cycle.
The air conditioner can be provided, and the pull-down (cool down) characteristics of the refrigeration / air conditioner can be improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a scroll compressor.

FIG. 2 is a diagram schematically illustrating a refrigeration / air-conditioning device.

[Explanation of symbols]

1: fixed scroll member, 2: orbiting scroll member, 3, 4
… End plate, 5,6… wrap, 7… crankshaft, 8… compression chamber, 9… discharge port, 10… frame, 11… pressure vessel, 12… discharge pipe, 13… motor, 14… oil hole, 15… Aldam ring, 16… Slide bearing, 17… Suction pipe, 18… Compressor, 19
... four-way valve, 20 ... outdoor heat exchanger, 21 ... expansion means, 22 ... indoor heat exchanger

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) F25B 1/00 395 F25B 1/00 395Z // C10N 40:30 (72) Inventor Kenichi Kawashima Omikamachi, Hitachi, Ibaraki, Japan No. 1-1, Hitachi, Ltd., Hitachi Research Laboratory, Hitachi, Ltd. (72) Inventor Toshi Iizuka 800, Odaira, Ohira-cho, Shimotsuga-gun, Tochigi Prefecture F-term (reference) 4H104 BB37C BB42A BB43A BB45A BB46A BD05C BH03C CB15A CB16A CB17A EA30C LA01 PA20

Claims (10)

[Claims] 1. A refrigerant comprising (A) one of propane and isobutane or a mixture thereof, and (B) a general formula (1) shown below. (Wherein, R 1 and R 2 each represent hydrogen or an alkyl group having 1 to 4 carbon atoms, and may be the same or different. R 3 to R 6 each represent hydrogen or a methyl group, and are the same as each other. X represents an oxyalkylene group having 2 to 4 carbon atoms, and m, n, p, and q each represent 1 to 3
Indicates the number of 0. However, when X does not exist, p and q are 0
And A working medium composition for a refrigerator / air conditioner, comprising: a polyalkylene glycol represented by the formula (1): 2. The polyalkylene glycol according to claim 1, which has the following general formula (2): (In the formula, R7 represents an alkyl group having 4 to 18 carbon atoms, an oleyl group, a phenyl group, or an o-, m-, p-tolyl group.)
A working medium composition for refrigeration / air conditioners, characterized in that the composition contains up to 5.0% by weight. 3. The polyalkylene glycol according to claim 1, which has the following general formula (3): (Wherein, R8 and R9 each independently represent hydrogen, fluorine, an alkyl group having 1 to 4 carbon atoms, or a perfluoroalkyl group having 1 to 4 carbon atoms. However, even if R8 and R9 are the same, A working medium composition for a refrigerator / air conditioner, comprising 0.05 to 5.0% by weight of the cyclic carbonate compound represented by the formula (1). 4. A method comprising: (A) a refrigerant comprising one of propane and isobutane or a mixture thereof; and (B) a compound having a low-temperature critical melting temperature of -40 ° C. or higher. Working medium composition for refrigerators and air conditioners. 5. The method according to claim 1, wherein the component (B) is at least one of a polyisopropylene glycol methyl ethyl ether compound and a methyl ethyl ether compound of a polyisopropylene glycol / polyethylene glycol copolymer. The working medium composition for a refrigeration / air conditioner according to item (1) or (4). 6. A refrigeration / air-conditioning apparatus provided with a refrigeration cycle for circulating refrigerant gas discharged from a compressor having a working medium for a refrigeration / air-conditioner through a condensing means, an expansion means, and an evaporating means. The working fluid for the engine is (A) a refrigerant composed of one of propane and isobutane or a mixture thereof, and (B) a refrigerant represented by the following general formula (1). (Wherein, R 1 and R 2 each represent hydrogen or an alkyl group having 1 to 4 carbon atoms, and may be the same or different. R 3 to R 6 each represent hydrogen or a methyl group, and are the same as each other. X represents an oxyalkylene group having 2 to 4 carbon atoms, and m, n, p, and q each represent 1 to 3
Indicates the number of 0. However, when X does not exist, p and q are 0
And And a polyalkylene glycol represented by the formula (1). 7. The polyalkylene glycol according to claim 6, which has the following general formula (2): (In the formula, R7 represents an alkyl group having 4 to 18 carbon atoms, an oleyl group, a phenyl group, or an o-, m-, p-tolyl group.)
A refrigeration / air conditioner characterized by containing 0% by weight. 8. The polyalkylene glycol according to claim 6, which has the following general formula (3): (Wherein, R8 and R9 each independently represent hydrogen, fluorine, an alkyl group having 1 to 4 carbon atoms, or a perfluoroalkyl group having 1 to 4 carbon atoms. However, even if R8 and R9 are the same, A refrigeration / air-conditioning apparatus comprising 0.05 to 5.0% by weight of a cyclic carbonate compound represented by the formula (1): 9. A refrigeration / air-conditioning apparatus having a refrigeration cycle for circulating refrigerant gas discharged from a compressor having a working medium for a refrigeration / air-conditioner through a condensing means, an expansion means, and an evaporating means. The mechanical working medium comprises (A) a refrigerant comprising one of propane and isobutane or a mixture thereof, and (B) a compound having a low-temperature critical melting temperature of -40 ° C or higher. Refrigeration and air conditioning equipment. 10. The component (B) is a polyisopropylene glycol methyl ethyl ether compound or at least one of methyl ethyl ether compounds of a polyisopropylene glycol / polyethylene glycol copolymer. The refrigeration / air-conditioning device according to claim (6) or (9).