JPS59109593A - Refrigerator oil composition - Google Patents

Abstract

PURPOSE:To provide a refrigerator oil composition which shows improved stability in a cooling medium atmosphere, controls generation of hydrogen chloride and prevents corrosion of the interior of a refrigerator, prepared by adding a 15-crown-5 derivative to a mineral or synthetic base oil. CONSTITUTION:The refrigerator oil composition is prepared by adding a 15- crown-5 derivative to a mineral oil and/or synthetic oil preferably having a viscosity of 1-50cst at 100 deg.C. The mineral oil includes lubricating oil fraction such as naphthenic, intermediate and paraffinic oils and highly aromatic components obtained by cracking of these mineral oils. The synthetic oils are, e.g., straight- chain and branched alkylbenzenes, polyethylene and ester oil. Preferred 15- crown-5 derivatives are benzo-15-crown-5 of formula I and cyclohexyl-15-crown-5 of formula II.

Description

[Detailed description of the invention] The present invention relates to a refrigerating machine oil composition.

Conventionally, base oils obtained from naphthenic base oils of high quality and highly refined have been widely used as excellent refrigerating machine oils. However, these naphthi-based crude oils are becoming extremely difficult to obtain because their production is low worldwide and there is a strong tendency for them to dry up. Therefore, it is necessary to effectively utilize naphthenic base oils, paraffinic base oils, and other synthetic base oils of poor quality that contain relatively large amounts of impurities as refrigeration base oils.

Generally, the required properties for normal refrigeration oil are f
l) have appropriate viscosity, (2) have excellent low temperature performance, (3) have a low critical melting temperature with the refrigerant, (4) have good performance in the shield tube test, and (5) thermal Stability, for example, excellent performance in panel coking tests.

When using naphthenic base oils or paraffinic base oils of poor quality that contain relatively many impurities to meet these required properties, the biggest problem is stability when in contact with halogen-based refrigerants. That is, the ability to prevent generation of hydrogen chloride due to the reaction between refrigerating machine oil and refrigerant is extremely low. In order to cope with this problem, various stabilizers have been proposed. Examples of these stabilizers include glycidyl ether-type epoxy compounds such as phenyl glycidyl ether and octyl epoxy stearate, and/or epoxidized fatty acid monoesters (JP-A-55-152005) , JP-A-55-140469.

JP-A-55-58298, U.S. Patent No. 2!5582
0B'4 Publication). However, even with the use of these stabilizers, it has not yet been possible to obtain sufficiently satisfactory stability, and to date it has been extremely difficult to produce high-performance refrigeration oil from base oils other than high-quality naphthenic base oils. It is difficult.

Therefore, in order to produce high-performance refrigeration oil from naphthenic base oil or paraffinic base oil, etc., which are of poor quality, the present inventor conducted intensive research on stabilizers to improve the stability of these base oils. The present invention was completed based on the knowledge that the objective can be achieved by adding a specific compound.

That is, the present invention provides mineral oil and/or synthetic oil with 15-
A refrigerator base oil composition containing a Crown-5 derivative is provided.

The mineral oil and/or synthetic oil is the base of the composition of the present invention, and is not particularly limited, but preferably has a viscosity of 1 to 50 cT3t at 100°C. Specifically, mineral oils include 7-ten type mineral oil and intermediate type mineral oil.

Examples include lubricating oil fractions of paraffinic mineral oils and high aromatic components obtained by decomposition of these mineral oils.
Examples of synthetic oils include linear alkylbenzenes; branched alkylbenzenes: polyolefin oils such as gelyethylene, polypropylene, and polybutene; alkylnaphthalenes; ester oils; and polyglycol oils. The above-mentioned oils can be used alone or in combination of two or more. Furthermore, it is preferable that the mineral oil and/or synthetic oil used be treated with clay. A major feature of the stabilizer according to the present invention is that a high-performance refrigerating machine oil can be produced by adding it to mineral oil and/or synthetic oil that is not originally suitable as a refrigerating base oil.

The 15-crown-5 derivative used in the present invention has the effect of preventing mineral oil and/or synthetic oil from generating hydrogen chloride in a refrigerant atmosphere1 and improving stability.

Preferred specific examples of the 15-crown-5 derivative are shown below.

15-crown-5benzo-15-crown-5 All of these are manufactured by known methods, for example, 15-crown-5 is manufactured by Japan f! El! 4J, benzo-15-crown-5, cyclohexyl-15-crown-5,t
ert;-butylbenzo-15-crown-5 is FOR
Available as a product of RgSgARau OHEM WORKS 0ALSIIJO.

The refrigeration oil composition of the present invention can be obtained by adding the above-mentioned 15-crown-5 derivative to mineral oil needle and/or synthetic oil. The addition of 15-crown-5 derivative is also 1,000
The amount is 1 to 10 parts by weight, preferably 0.001 to 7 parts by weight, particularly preferably 0.1 to 5 parts by weight.

The refrigerating machine oil composition thus obtained can be effectively used as a lubricant for refrigerating machines. The refrigerating machine oil composition according to the present invention has extremely high stability in a refrigerant atmosphere,
Since the generation of hydrogen chloride is suppressed, corrosion inside the refrigerator can be prevented.

Furthermore, in the present invention, even if many base oils other than high-quality 7-ten base oils, which are not originally suitable for refrigerating machine oils, are used,
Since it is possible to obtain a high-performance refrigerating machine oil with excellent stability, it is extremely beneficial in terms of resources and economy.

Next, the present invention will be explained in detail with reference to examples.

Examples 1 to 7 Refrigerating machine oil compositions were obtained by adding a predetermined amount of the stabilizers shown in Table 1 to low-quality naphthenic base oil or synthetic oil.

A sealed tube test was conducted on these compositions. The results are shown in Table 1.

Comparative Examples 1 to 7 Pre-refrigerator compositions were obtained with or without adding a predetermined amount of stabilizer to low-quality naphthenic base oil or synthetic oil. A shield tube test was conducted on these in the same manner as in Examples 1 to 7. The results are shown in Table 1.

[Experimental conditions for shield tube test] A 10 m/Pyrex glass ampoule with a pressure resistance of 20 and 9 f/cffl was used as the tube. The temperature was 175°C for 250 hours. Sample 4d, Freon (CF2Ct2) as refrigerant
(manufactured by Daikin Industries, Ltd., product name: DAIFLON-12) 2? , Our Fe and At as catalysts each 1.
6φ×4 cabinets were used.

Table 1 shows the results regarding the amount of hydrochloric acid generated, the discoloration of the oil, and the appearance of the catalyst after the experiment.

・I: After deep cooling the ampoule with liquid nitrogen, open it and store it for about 100te.
One end of the opened bottle was placed in 1 liter of distilled water, and the generated hydrogen chloride was absorbed into the distilled water, followed by titration with a 0.1 N I (OH solution).

Medium 27M0 oil N-90 (manufactured by Idemitsu Kosan) Sulfur content 0
．． 5% by weight, viscosity 9 cst at 100°C, ring analysis value: %CA659%CN592%CP54.5, and 8% by weight clay treatment was used.

・S: ADH-8H (manufactured by Mitsubishi Yuka) Specific gravity is 1
089 at 5/4°C. The viscosity is 4.5 cst at 1000C, and the pour point is below -40°C.

Patent applicant: Idemitsu Kosan Co., Ltd.

Claims (1)

[Claims] (11 mineral oil and/or synthetic oil with 15-crown-5
A refrigerating machine oil composition containing a derivative. (2) 1 per 100 parts by weight of mineral oil and/or synthetic oil
The refrigerating machine oil composition according to claim 1, wherein o, o o i to 10 parts by weight of a 5-crown-5 derivative is added.