JP3350467B2 - Lubricating oil for copper pipe processing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating oil for processing copper pipes which is suitable for drawing and rolling of long annealed coil copper pipes used for heat exchangers of refrigeration systems such as air conditioners and refrigerators. In particular, the residue after annealing in a coil shape (residual oil and other carbides in the pipe) is small, and the lubricity and anti-seizure property of the pipe inner surface can be improved. The present invention relates to a lubricating oil for processing copper pipes, which can prevent the refrigeration system from having an adverse effect.

[0002]

2. Description of the Related Art Conventionally, heat transfer tubes have been used in room air conditioners, air conditioners for automobiles, refrigerators, dehumidifiers, freezers, refrigerated warehouses, vending machines, heat exchangers of refrigeration systems such as showcases and chemical plants, and the like. It is used. In consideration of workability, heat transferability, workability and corrosion resistance, this heat transfer tube is formed by processing a copper or copper alloy tube (hereinafter, copper or copper alloy tube is collectively referred to as a copper tube) and then softening by annealing. A long coiled copper tube or the like is used. In the process of manufacturing such a long annealed coil copper tube, the raw tube is processed into a copper tube by a drawing process using lubricating oil on the inner surface and the outer surface, and after being wound into a coil shape, reduced. Heat annealing is performed at a temperature of 500 ° C. or higher in a neutral atmosphere or an inert atmosphere. The annealing condition is about 500 ° C.
After heating at a temperature of several tens of minutes, it is cooled to obtain a predetermined refining.

[0003] By the way, when a copper pipe is subjected to drawing processing, a lubricating oil whose kinematic viscosity has been adjusted by adding a fatty acid ester or isoparaffin to a high-viscosity high-molecular synthetic hydrocarbon such as polybutene is conventionally used. Used on the inner and outer surfaces of pipes. When a heat treatment is performed on the copper tube at about 500 ° C., which is an annealing cycle of the long coil copper tube, for several tens of minutes, these lubricating oils conventionally used evaporate or become one. The part is reduced in molecular weight and evaporates.

However, in this annealing cycle, the molecular weight of the lubricating oil may not be sufficiently reduced, and as a result, components that do not vaporize at room temperature may be generated. Therefore, if the coil length is long or the tube diameter is small,
Only by volume expansion of the gasified lubricating oil component, the inner lubricating oil used for copper pipe processing may not be completely discharged out of the pipe. As a result, some of the gas components are condensed in the cooling process, and residual oil and residues are generated in the tubes.

[0005] In recent years, chlorofluorocarbons (HCF) have been used as refrigerants for refrigeration and air-conditioning systems.
Instead of C-type) and chlorofluorocarbon-type (CFC-type) refrigerants, hydrofluorocarbon-type (HFC-type) refrigerants containing no chlorine have been used.

However, the HFC-based refrigerant is not compatible with the hydrocarbon-based oil, and when oil remains in the copper pipe, the residual oil in the pipe may hinder the operation of the refrigeration system in the refrigeration system. It may cause problems such as capillaries of capillaries due to contamination or contamination.

[0007] Furthermore, the residual oil in the long annealed coil copper tube is:
In the brazing operation at the time of assembling the heat exchanger of the refrigeration system, gas is generated or carbide is generated, which causes brazing failure.

[0008] In order to solve these various disadvantages,
There is a strong demand for reducing the residual oil in the long annealed coil copper tube and reducing the influence of the residue after annealing on the refrigeration system.

As a conventional method of reducing residual oil in such a long annealed coil copper tube, there is a method of using an exhaust pump during heat annealing or a method of sucking and removing gas in the tube in a vacuum chamber. Further, a method has been proposed in which the gas in the tube is purged with nitrogen or an inert gas during heat annealing (JP-A-6-279860 and JP-A-7-197283). It is also known that the combination of the two can reduce the residual lubricating oil on the inner surface of the pipe (Japanese Patent Application Laid-Open No. 6-228649).

[0010]

However, a method of sucking and removing gas remaining in the copper tube by an exhaust pump during heat annealing of the copper tube, a method of sucking and removing gas in the tube in a vacuum chamber,
Or when using the method of purging the gas in the pipe with an inert gas etc., it is necessary to modify the equipment for that,
There is a problem that productivity decreases and manufacturing cost increases. Further, if the kinematic viscosity of the lubricating oil is not adjusted, or if a solvent and an oil agent for adjusting the kinematic viscosity are not properly selected, the lubricity may be reduced during drawing of the copper tube. This causes seizure of the plug.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is possible to reduce the residual oil in a long coil copper tube at low cost without performing a special residual oil removal treatment such as purging on a long coil copper tube in an annealing furnace. This can improve the brazing property of the copper tube, improve the lubricity at the time of drawing or rolling and prevent seizure, and further reduce the residue after annealing by a refrigeration system. It is an object of the present invention to provide a lubricating oil for processing copper pipes, which can prevent adverse effects on the pipe.

[0012]

The lubricating oil for copper pipe processing according to the present invention has a general formula: R ₁ -O-
(R ₂ —O) _n —R ₃ (where R ₁ and R _{3 are a} hydrogen atom or an alkyl group, R ₂ is an alkylene group having 4 to 6 carbon atoms,
n: 10 to 100), a base oil composed of at least one selected from the group consisting of polyalkylene glycols, which are homopolymers represented by the following formulas, and alkyl ethers of the polyalkylene glycols: 70 to 99.5% by mass, and , Ethylene glycol, ethylene glycol 2 to
10-mer , propylene glycol, propylene glycol
2 to 10 mer Le, glycerol, diglycerol, triglycerol, trimethylolethane, partial ethers of dihydric or polyhydric alcohols of one selected from the group consisting of trimethylol propane and trimethylol butane products or 2 Mixture of partially etherified polyhydric alcohols of at least two or more polyhydric alcohols: 0.5 to 30% by mass. Further, the other lubricating oil for copper pipe processing according to the present invention has a general formula: R ₁ -O- (R ₂
—O) _n —R ₃ (where R ₁ and R _{3 are a} hydrogen atom or an alkyl group, R ₂ is an alkylene group having 3 to 6 carbon atoms, n: 1)
0 to 100), a base oil composed of at least one selected from the group consisting of polyalkylene glycols which are copolymers represented by the formula (1) and alkyl ethers of the polyalkylene glycols: 70 to 99.5% by mass, and ethylene Glycol, 2 to 10 amounts of ethylene glycol
Body , propylene glycol, propylene glycol 2
1 to 10 mer , selected from the group consisting of glycerin, diglycerin, triglycerin, trimethylolethane, trimethylolpropane and trimethylolbutane
0.5 to 30% by mass of a partial etherified product of two or more polyhydric alcohols or a partial etherified product of two or more polyhydric alcohols.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The inventors of the present application have conducted various studies to reduce residual oil in long coiled copper tubes and to develop lubricating oils for copper tube processing having excellent lubricity during drawing and rolling. Was done. As a result, any one selected from the group consisting of polyalkylene glycols and alkyl ethers of polyalkylene glycols is used as a base oil, and a lubricant containing a predetermined amount of partially etherified polyhydric alcohol is used as a lubricating oil. Thus, to obtain a long coil copper tube with improved lubricity at the time of drawing or rolling, the residual oil in the tube after annealing is significantly reduced, and the adverse effect on the refrigeration system of the residue after annealing is significantly reduced. I found that I can do it.

Hereinafter, the lubricating oil for copper pipe processing according to the present invention will be described in detail.

Polyalkylene glycol and polyalkyl
Select from the group consisting of alkyl ethers of len glycol
Base oil consisting of at least one kind: 70 to 99.5
Weight% conventional polybutene-based lubricating oil, after pyrolysis randomly during annealing, but most of the low molecular weight may be vaporized, and the remaining portion was polymerized by condensation polymerization, the change in high-boiling components I do. Then, the high boiling point component adheres to the inner surface of the tube and is carbonized by thermal decomposition.

However, polyalkylene glycols (PA
Since the alkyl ethers of G) and PAG are easily decomposed themselves, they are decomposed into monomers or oligomers and vaporized. Since these decomposition products have a relatively low boiling point and do not condense even after being cooled in the furnace, the lubricating oil component is discharged out of the tube when the inside of the tube is purged after annealing.
Therefore, by using at least one selected from the group consisting of PAG and alkyl ethers of PAG as the base oil of the lubricating oil, it is possible to reduce the oil content remaining in the pipe after annealing. In addition, the use of this base oil can reduce the adverse effects of the residue after annealing on the refrigeration system.

When the content of the base oil per the total mass of the lubricating oil is 70,
If the amount is less than mass%, the effect of using at least one base oil selected from the group consisting of PAG and alkyl ethers of PAG cannot be sufficiently obtained, and the residual oil content may increase. On the other hand, the base oil content is 99.
If the amount exceeds 5% by mass, the effect of the partially etherified polyhydric alcohol having a valency of 2 or more contained in the lubricating oil cannot be obtained. Therefore, in the present invention, the content of the base oil is set to 70 to 99.5% by mass based on the total mass of the lubricating oil.

The general formula R ₁ -O- (R ₂ -O) _n -R ₃
In the polyalkylene glycol represented by and the alkyl ether of the polyalkylene glycol, R ₁ and R ₃ are each a hydrogen atom or an alkyl group, and they may be the same or different. R ₂ is an alkylene group, and n R _{2 s} may be the same or different. Further, n is an integer of 10 to 100.

When one or both of R ₁ and R ₃ are an alkyl group, the number of carbon atoms of the alkyl group can be arbitrarily selected. May remain in the tube. Therefore, the alkyl group preferably has 1 to 18 carbon atoms, and more preferably 1 to 10 carbon atoms. The alkyl group may be linear or branched, and specifically, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, s
cc-butyl group, tert-butyl group, linear or branched pentyl group, linear or branched hexyl group, linear or branched heptyl group, linear or branched Octyl group, linear or branched nonyl group, linear or branched decyl group, linear or branched undecyl group, linear or branched dodecyl group, Linear or branched tridecyl group, linear or branched tetradecyl group, linear or branched pentadecyl group, linear or branched hexadecyl group, linear or branched And a linear or branched octadecyl group.

Although the number of carbon atoms of R ₂ (alkylene group) is not particularly limited, it is generally preferable that the number of carbon atoms be 2 to 10. Specific examples of such a divalent hydrocarbon group having 2 to 10 carbon atoms (alkylene group) include an ethylene group, a propylene group (including a 1-methylethylene group and a 2-methylethylene group), and a trimethylene group. Group, butylene group (including 1-ethylethylene group and 2-ethylethylene group), 1,2-dimethylethylene group,
2,2-dimethylethylene group, 1-methyltrimethylene group, 2-methyltrimethylene group, 3-methyltrimethylene group, tetramethylene group, pentylene group (including 1-butylethylene group and 2-butylethylene group) , 1-ethyl-1-methylethylene group, 1-ethyl-2-methylethylene group, 1,1,2-trimethylethylene group, 1,
2,2-trimethylethylene group, hexylene group (including 1-butylethylene group and 2-butylethylene group), 1
-Methyl-1-propylethylene group, 1-methyl-2-
Propylethylene group, 2-methyl-2-propylethylene group, 1,1-diethylethylene group, 1,2-diethylethylene group, 2,2-diethylethylene group, 1-ethyl-1,2-dimethylethylene group, 1-ethyl-2,2-
Dimethylethylene group, 2-ethyl-1,1-dimethylethylene group, 2-ethyl-1,2-dimethylethylene group,
1,1,2,2-tetramethylethylene group, heptylene group (including 1-pentylethylene group and 2-pentylethylene group), octylene group (including 1-hexylethylene group and 2-hexylethylene group), nonylene Group (1-
A heptylethylene group and a 2-heptylethylene group), a decylene group (including a 1-octylethylene group and a 2-octylethylene group), and the like.

Among these, as R ₂ , it is preferable to use an alkylene group having 3 or more carbon atoms from the viewpoints of low hygroscopicity, excellent lubricity, and difficulty in hydrolysis. It is even more preferred to use an alkylene group having 4 or more. The polyalkylene glycol having high hygroscopicity may generate a lower carboxylic acid, which is a nest-like corrosive medium, by decomposition, and may leak in a short time when attached to a copper tube. Further, R ₂ is an alkylene group having a carbon number of 8 or less from the viewpoint that the residue during annealing can be further reduced, and that the residue after annealing can reduce adverse effects on the refrigeration system. It is preferable to use an alkylene group having 6 or less carbon atoms.

The general formula R ₁ -O- (R ₂ -O) _n -R ₃
In the above, even when only one alkylene group (R ₂ ) having the same structure is contained in the same molecule (homopolymer), two kinds of alkylene groups having different structures are contained in the same molecule (copolymer) It may be. When a copolymer is used, the monomer ratio and the sequence of the monomers constituting the copolymer are not limited, and may be any of a random copolymer, an alternating copolymer, and a block copolymer. .

When the general formula R ₁ —O— (R ₂ —O) _n —R ₃ is a homopolymer, R ₂ has low hygroscopicity,
It has excellent lubricity, does not easily undergo hydrolysis, and can further reduce the residue (residual carbon) during annealing.
It is preferable to use an alkylene group having 4 to 6 carbon atoms from the viewpoint that the residue after annealing can reduce the adverse effect on the refrigeration system. If a butylene group is used, the raw material can be easily obtained. Is more preferable.

When the general formula R ₁ —O— (R ₂ —O) _n —R ₃ is a copolymer, R ₂ has low hygroscopicity, excellent lubricating properties, and hydrolysis occurs. Alkylene groups having 3 to 6 carbon atoms are used because they are difficult to reduce, and the residue after annealing can be further reduced, and the adverse effects of the residue after annealing on the refrigeration system can be reduced. It is more preferable to use a propylene group and a butylene group because the raw materials can be easily obtained.

Further, in the present invention, if n of the compound represented by the above general formula is less than 10, the boiling point may be lowered, so that the decomposability at the ether bond may be lowered. On the other hand, if n exceeds 100, the probability of remaining as a residual oil component increases even when the base oil has a structure that is easily decomposed. Also, the post-annealing residue may have an adverse effect on the refrigeration system. Therefore, n is set to 10 to 100.

In the present invention, the above R ₁ , R ₂ and R
_At least one of all polyalkylene glycols having ₃ and alkyl ethers of polyalkylene glycol can be used as a base oil for lubricating oil for copper pipe processing. When two or more compounds are used as a mixture, the mixing ratio of these compounds can be arbitrarily selected. In the present invention, the kinematic viscosity of the base oil of the lubricating oil is not particularly limited.

Partial ether of dihydric or higher polyhydric alcohol
Using at least one selected from the group consisting of alkyl ethers of PAG and PAG as a lubricating oil,
The drawing rate (area reduction rate) per drawing in the drawing process is set to, for example, 20% or more, the drawing speed is set to, for example, 10 m / sec or more, and a bull block is used. When the drawing process is performed, the lubricating boundary portion becomes high in temperature due to heat generated during the process, the lubricity is reduced, seizure occurs on the floating plug, and the production yield may be reduced due to the drawing fracture. In particular, when a long copper or copper alloy tube is used, the temperature of the tube increases due to the drawing process, and the lubricity is significantly reduced.

When at least one selected from the group consisting of PAG and alkyl ethers of PAG is used as the base oil, lubricating properties are insufficient depending on the drawing method depending on the drawing method, and high-temperature lubrication is required only by adding alcohol. Cannot be improved. Furthermore, in order to improve lubricity,
When the chain length is increased by increasing the carbon number of the alcohol, the amount of residual oil after annealing increases, and the adverse effect of the residue after annealing on the refrigeration system increases.

Therefore, in the present invention, the above base oil and 2
A lubricating oil containing a partially etherified product of a polyhydric alcohol having a valence of 3 or more is used. If the content of the partially etherified polyhydric alcohol is less than 0.5% by mass based on the total mass of the lubricating oil, good lubricity cannot be maintained. On the other hand, the content of the partially etherified polyhydric alcohol is 30% by mass.
Even if it exceeds 3, the effect of improving lubricity saturates, and the effect associated with the added amount cannot be obtained. Further, the partially etherified product of the polyhydric alcohol is easily vaporized, but if the content of the partially etherified product of the polyhydric alcohol in the lubricating oil exceeds 30% by mass, the probability of remaining as a residual oil component after annealing is high. Will be higher. Therefore, in the present invention, the content of the partially etherified dihydric or higher polyhydric alcohol in the lubricating oil is set to 0.5 to 30% by mass.

Specific examples of polyhydric alcohols having two or more valencies include ethylene glycol, propylene glycol, trimethylene glycol (1,3-propanediol),
Butylene glycol (1,2-butanediol), 1,
1-dimethylethylene glycol (2-methyl-1,3
-Propanediol), 1,2-dimethylethylene glycol (2,3-butanediol), 1-methyltriethylene glycol (1,3-butanediol), 2-methyltrimethylene glycol (2-methyl-1,3 -Propanediol), tetramethylene glycol (1,4
-Butanediol), pentylene glycol (1,2-
Pentanediol), 2,2-dimethyltrimethylene glycol (2,2-dimethyl-1,3-propanediol), 1,5-pentanediol, neopentyl glycol, hexylene glycol (1,2-hexanediol), 1,6-hexanediol, 2-ethyl-2-methyl-1,3-propanediol, 1,7-heptanediol, 2-methyl-2-propyl-1,3-propanediol, 2,2-diethyl- Dihydric alcohols such as 1,3-propanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, and 1,12-dodecanediol; There are dimer to decamer of the hydric alcohol.

Further, trimethylolethane, trimethylolpropane, trimethylolbutane, di- (trimethylolpropane), tri- (trimethylolpropane), pentaerythritol, di- (pentaerythritol), tri- (pentaerythritol), Glycerin, polyglycerin (2-8 glycerin),
There are also polyhydric alcohols such as 1,3,5-pentanetriol, sorbitol, sorbitan, sorbitol glycerin condensate, adonitol, arabitol, xylitol and mannitol.

Further, xylose, arabinose, ribose, rhamnose, glucose, fructose, galactose, mannose, sorbose, cellobiose, maltose, isomaltose, trehalose, sucrose,
There are polyhydric alcohols such as raffinose, gentianose, and melezitose, all of which are partially etherified and methyl glucoside (glycoside) alone or mixed,
A lubricant can be added to the base oil.

Among these polyhydric alcohols, ethylene glycol, polyethylene glycol (2 to 10 mer of ethylene glycol), propylene glycol, polypropylene glycol (2 to 10 mer of propylene glycol), glycerin, diglycerin, By incorporating triglycerin, trimethylolethane, trimethylolpropane and trimethylolbutane and a partially etherified product of these mixtures in a lubricating oil, excellent workability can be obtained, and a residual oil content in a pipe after annealing. Can be reduced, and the adverse effect of the residue after annealing on the refrigeration system can be reduced. In addition, ethylene glycol, polyethylene glycol (ethylene glycol dimer to octamer), propylene glycol, polypropylene glycol (propylene glycol dimer to octamer), glycerin and diglycerin, and partially etherified products of these mixtures are used as lubricating oils. It is even more preferable to contain them. Most preferably, the lubricating oil contains ethylene glycol, polyethylene glycol (ethylene glycol dimer to hexamer), propylene glycol and glycerin, and partially etherified products of these mixtures.

In the above-mentioned polyhydric alcohol, if all the hydroxyl groups are etherified, it is not preferable because lubricity is reduced. Therefore, in the present invention, it is preferable that at least one of the hydroxyl groups of the polyhydric alcohol remains without being etherified. Particularly, a monoetherified product in which one of the hydroxyl groups of the polyhydric alcohol is etherified is more preferable.

As the etherification, any of alkyl etherification, alkenyl etherification, cycloalkyl etherification, alkylcycloalkyl etherification, aryl etherification, alkylaryl etherification and arylalkyl etherification may be used. In particular, when the above-mentioned polyhydric alcohol is alkyl etherified, the amount of oil remaining in the tube after annealing can be further reduced, and the adverse effect of the residue after annealing on the refrigeration system can be further reduced. You can get oil.

The number of carbon atoms in the alkyl group to be ether-bonded is not particularly limited. For example, an etherified product of an alkyl group having 1 to 18 carbon atoms and a polyhydric alcohol is used as the lubricating oil component. Can be. Examples of the alkyl group having 1 to 18 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group,
n-butyl group, isobutyl group, scc-butyl group, te
an rt-butyl group, a linear or branched pentyl group, a linear or branched hexyl group, a linear or branched heptyl group,
Straight or branched octyl group, straight or branched nonyl group, straight or branched decyl group, straight or branched undecyl group, straight or branched dodecyl group, Straight or branched tridecyl group, straight or branched tetradecyl group,
There are a straight or branched pentadecyl group, a straight or branched hexadecyl group, a straight or branched heptadecyl group, a straight or branched octadecyl group, and the like.

Of these alkyl groups, those having 3 or more carbon atoms are preferred from the viewpoint of odor, and those having 5 or more carbon atoms are even more preferred. In addition, the carbon number is 16
If it is below, the amount of residual oil in the pipe after annealing can be further reduced, and the adverse effect of the residue after annealing on the refrigeration system can be further reduced.
Further, the carbon number is preferably 14 or less, and the carbon number is 1 or less.
It is even more desirable that the number be 2 or less.

Partially etherified base oil and polyhydric alcohol
In the present invention, a known lubricating oil additive, such as an oil-based additive, is used in the drawing step in which drawing property is required in order to enhance the performance as a drawing lubricating oil. Agents or the like may be included in the lubricating oil alone or in combination of two or more. As the oily agent, fatty acids, fatty acid esters, fatty acid metal salts, aliphatic alcohols, and the like can be used. However, when the content of the additional component such as the oily agent increases, the residual oil in the pipe after annealing the coil and other oils Residues such as carbides may increase, or the residue after annealing may have an adverse effect on the refrigeration system. Therefore, the content of the additional component such as an oil agent is preferably 10% by mass or less, more preferably 5% by mass or less, even more preferably 2.5% by mass or less based on the total mass of the lubricating oil.

That is, the total amount of the base oil and the partially etherified polyhydric alcohol is preferably at least 90% by mass, more preferably at least 95% by mass, and even more preferably 97.5% by mass, based on the total mass of the lubricating oil. % Is still more preferred. It is even more preferable to use a lubricating oil consisting only of a base oil and a partially etherified product of a polyhydric alcohol and containing no additional components. When a lubricating oil containing an additional component such as an oil agent is used as a lubricating oil for drawing processing, the lubricating oil containing no additional component is used for finishing and the attached lubricating oil in the pipe is added to the additional component. It is preferable to perform annealing after replacing with lubricating oil containing no.

Kinematic viscosity of lubricating oil at 40 ° C .: 50 to
When the kinematic viscosity of 2000 mm ² / sec Lubricating oil is less than 50 mm ² / s, sometimes oil amount remaining in the tube after the annealing increases. Also,
If the kinematic viscosity of the lubricating oil is less than 50 mm ² / sec, the lubricity may decrease. On the other hand, the kinematic viscosity of the lubricating oil is 200
If it exceeds 0 mm ² / sec, the amount of residual oil in the pipe after annealing may increase. Therefore, in the present invention, the kinematic viscosity of the lubricating oil at 40 ° C. is preferably set to 50 to 2000 mm ² / sec. As a method of adjusting the kinematic viscosity of the lubricating oil, it is preferable to adjust n of the base oil represented by the general formula R ₁ -O- (R ₂ -O) _n -R ₃ within the range of the present invention.

In the present invention, a room air conditioner,
Refrigerants used in air conditioners for automobiles, refrigerators, dehumidifiers, freezers, freezer and refrigerated warehouses, vending machines, heat exchangers for refrigeration systems such as showcases and chemical plants,
HFC-based refrigerants and HFC-based refrigerants and hydrocarbons (HC refrigerants)
And the like can be used.

The HFC-based refrigerant has 1 to 3 carbon atoms.
Are known. Specifically, difluoromethane (HFC-32), trifluoromethane (HFC-23), pentafluoroethane (HFC)
FC-125), 1,1,2,2-tetrafluoroethane (HFC-134), 1,1,1,2-tetrafluoroethane (HFC-134a), 1,1,1-trifluoroethane (HFC HFCs such as -143a) and 1,1-difluoroethane (HFC-152a), and mixtures of two or more thereof.

As the mixed refrigerant of the HFC-based refrigerant, for example, a mixed refrigerant of 60 to 80% by mass of HFC-134a and 20 to 40% by mass of HFC-32;
Mass% HFC-32 and 30 to 60 mass% HFC-
HFC-1 containing 40 to 60% by mass of a mixed refrigerant with 125
A mixed refrigerant of 25 and 40 to 60% by mass of HFC-143a, 60% by mass of HFC-134a and 30% by mass of H
A refrigerant mixture of FC-32 and 10% by mass of HFC-125, 40 to 70% by mass of HFC-134a, 15 to 35% by mass of HFC-32 and 5 to 40% by mass of HFC
-125 and HF of 35 to 55% by mass
C-125 and 1 to 15% by mass of HFC-134a and 4
A refrigerant mixture with 0 to 60% by mass of HFC-143 can be used.

As the mixed refrigerant of the HFC-based refrigerant, specifically, 70% by mass of HFC-134a and 30% by mass of HF
Refrigerant mixed with C-32, 60% by mass of HFC-32 and 4
A refrigerant mixture of 0% by mass of HFC-125 and a refrigerant mixture of 50% by mass of HFC-32 and 50% by mass of HFC-125 (R410A; Gentron AZ-2, manufactured by Allied Signal Inc.)
0), 45% by weight of HFC-32 and 55% by weight of HFC
-125 mixed refrigerant (R410B; manufactured by DuPont, SU
VA AC9100), a mixed refrigerant of 50% by mass of HFC-125 and 50% by mass of HFC-134a (R507C; Allied Signal Corp., Gentron AZ-50), 30% by mass of H
FC-32 and 10% by mass of HFC-125 and 60% by mass
Refrigerant with HFC-134a, 23% by mass HFC
-32 and 25% by weight of HFC-125 and 52% by weight of H
Refrigerant mixed with FC-134a (R407C; manufactured by DuPont, SUVA AC9000), and 44% by mass of HFC-125
And 4% by mass of HFC-134a and 52% by mass of HFC-
143a and a mixed refrigerant (R404A; manufactured by DuPont, SU
VA HP-62).

As the hydrocarbon-based refrigerant, alkanes, cycloalkanes and alkenes having 1 to 6 carbon atoms, and refrigerant mixtures thereof can be used. Specifically, for example, methane, ethylene, ethane, propylene, propane, cyclopropane, butane, isobutane,
Cyclobutane and methylcyclopropane, and mixtures of two or more thereof, can be used.

Further, in the present invention, the refrigerating machine oil used in the refrigerating system, that is, the compressor oil in the refrigerating system, may be at least one selected from the group consisting of mineral oil and synthetic oil, Can be used.

The mineral oil used as the refrigerating machine oil includes:
Specifically, the lubricating oil fraction obtained by atmospheric distillation and vacuum distillation of crude oil is subjected to solvent dewatering, solvent extraction, hydrocracking, solvent dewaxing, catalytic dewaxing, hydrorefining, sulfuric acid refining, Of the washing and clay treatment, paraffinic or naphthenic mineral oil obtained by combining one or more refining means can be used as the refrigerating machine oil.

As the synthetic oil used as the refrigerating machine oil, specifically, synthetic oxygenated oils such as polyolefin, alkylbenzene, ester, ether, silicate and polysiloxane can be used as the refrigerating machine oil. In particular, it is preferable to use polyolefin, alkylbenzene, ester, ether and the like.

Among the synthetic oils used as refrigerating machine oils,
The polyolefin refers to homopolymers and copolymers of olefins having 2 to 16 carbon atoms, preferably 2 to 12 carbon atoms, and hydrides thereof. When the polyolefin is a copolymer of olefins having different structures, there is no particular limitation on the monomer ratio and monomer arrangement in the copolymer, and any of a random copolymer and an alternating copolymer may be used. Is also good.

The olefin monomer forming the polyolefin may be an α-olefin or an internal olefin, and may be a linear olefin or a branched olefin.

Specific examples of the olefin that can be used in producing the polyolefin include ethylene, propylene, 1-butene, 2-butene, isobutene, linear or branched pentene (α-olefin) Hexene (including α-olefins and internal olefins), linear or branched heptene (including α-olefins and internal olefins), linear Or a branched octene (including an α-olefin and an internal olefin), a linear or branched nonene (including an α-olefin and an internal olefin), a linear or branched decene (an α-olefin) And an internal olefin), a linear or branched undecene (including an α-olefin and an internal olefin), a linear or branched dodecene (α-O Including olefins and internal olefins), linear or branched tridecene (α-
Olefins and internal olefins), linear or branched tetradecenes (including α-olefins and internal olefins), linear or branched pentadecenes (including α-olefins and internal olefins), and Chain or branched hexadecene (including α-olefins and internal olefins);

In particular, it is preferable to use ethylene, propylene, 1-butene, 2-butene, isobutene, an α-olefin having 5 to 12 carbon atoms, and a mixture thereof, and 5 to 12 carbon atoms. It is even more preferred to use 1-octene, 1-decene and 1-dodecene and mixtures thereof among the α-olefins.

The above-mentioned polyolefin can be produced by any method. For example, in addition to being able to be produced by a thermal reaction without a catalyst, it is possible to produce a polyolefin by homopolymerizing or copolymerizing an olefin using a known organic peroxide catalyst such as benzoyl peroxide. it can. Examples of the organic peroxide catalyst include Friedel-Crafts catalysts such as aluminum chloride, aluminum chloride-polyhydric alcohol, aluminum chloride-titanium tetrachloride, aluminum chloride-alkyltin halide, and boron fluoride. . Organic aluminum chloride-titanium tetrachloride and organic aluminum-
Ziegler type catalysts such as titanium tetrachloride can be used. Further, using known catalyst systems such as aluminoxane-zirconocene-based, ionic compound-zirconocene-based metallocene-type catalysts, and aluminum chloride-base-based and boron fluoride-base-based Lewis acid complex-based catalysts such as, for example, The olefin can be homopolymerized or copolymerized.

In the present invention, the above-mentioned polyolefin can be used as a component of the refrigerating machine oil. However, since this polyolefin usually has a double bond, heat stability and oxidation stability are taken into consideration. Then, a hydride of a polyolefin obtained by hydrogenating a double bond in a polymer may be used. As a method for obtaining a polyolefin hydride, an appropriate method can be used.For example, a polyolefin is hydrogenated with hydrogen in the presence of a known hydrogenation catalyst to saturate a double bond present in the polyolefin. A method can be used. Also, by selecting the catalyst to be used, after polymerizing the olefin,
The two steps of the olefin polymerization step and the polymer hydrogenation step can be performed simultaneously without sequentially performing the two steps of hydrogenation.

Among the polyolefins that can be used as components of the refrigerator oil, ethylene-propylene copolymer and polybutene (butane-butene (a mixture of 1-butene, 2-butene and isobutene) by-produced during naphtha pyrolysis) fraction , 1-octene oligomer, 1-decene oligomer and 1-dodecene oligomer, and their hydrides and mixtures thereof have thermal stability, oxidation stability, viscosity-temperature. It can be used because of its excellent properties and low temperature fluidity. In addition, ethylene-propylene copolymer hydride, polybutene hydride, 1-octene oligomer hydride, 1-decene oligomer hydride, 1-dodecene oligomer hydride, and a mixture thereof can also be used.

Incidentally, synthetic oils such as ethylene-propylene copolymer, polybutene and poly-α-olefin which are commercially available as base oils for lubricating oils are usually those whose double bonds have already been hydrogenated. These commercial products can also be used as components of refrigerating machine oil.

Among the synthetic oils used as refrigerating machine oil, any alkyl benzene can be used. For example, an alkyl benzene having 1 to 4 alkyl groups having 1 to 40 carbon atoms can be used. Can be used. Specific examples of the alkyl group having 1 to 40 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group and an undecyl. Group,
Dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, icosyl, henycosyl, docosyl, tricosyl, tetracosyl, pentacosyl, hexacosyl, heptacosyl, octakosyl , Nonacosyl group, triacontyl group, hentriacontyl group, dotriacontyl group, tritriacontyl group,
There are a tetratriacontyl group, a pentatriacontyl group, a hexatriacontyl group, a heptatriacontyl group, an octatriacontyl group, a nonatriacontyl group, a tetracontyl group, and the like.
Alkyl benzenes, including all isomers, can be used as synthetic oils.

As the alkyl group of the alkylbenzene,
Although it may be linear or branched, it is preferable to use an alkylbenzene having a branched alkyl group as a synthetic oil from the viewpoint of stability and viscosity characteristics. Among them, alkylbenzene having a branched alkyl group derived from an oligomer of olefin such as propylene, butene and isobutylene is particularly preferably used as a refrigerating machine oil because it is easily available.

The number of alkyl groups in the alkylbenzene is preferably 1 to 4. However, from the viewpoint of stability and availability, monoalkylbenzene having one alkyl group and two alkyl groups are preferred. The dialkylbenzenes having these and mixtures thereof can be used as refrigerating machine oil. In addition, as alkylbenzene,
Not only alkylbenzene having a single structure but also a mixture of alkylbenzenes having different structures may be used.

Further, the method for producing alkylbenzene is not limited, but it can be generally synthesized by the following synthesis method. As the aromatic compound as a raw material, specifically, benzene, toluene, xylene, ethylbenzene and diethylbenzene,
In addition, mixtures thereof and the like can be used. As the alkylating agent, for example, among lower monoolefins such as ethylene, propylene, butene and isobutylene, preferably a linear or branched olefin having 6 to 40 carbon atoms obtained by polymerization of propylene is used. Can be used. Also, n- to C- to C-40 linear or branched olefins obtained by pyrolysis of wax, heavy oil, petroleum fraction, polyethylene and polypropylene, and petroleum fractions such as kerosene and gas oil. It is also possible to use a linear olefin having 9 to 40 carbon atoms obtained by separating paraffin and subjecting it to olefination with a catalyst, or a mixture of these olefins.

Further, as the alkylation catalyst for the alkylation, a Friedel-Crafts type catalyst such as aluminum chloride and zinc chloride, and an acid catalyst such as sulfuric acid, phosphoric acid, silicotungstic acid, hydrofluoric acid and activated clay are used. Catalysts, etc.
Known alkylation catalysts can be used.

Among the synthetic oils used as refrigerating machine oils,
Esters include dibasic acid esters, polyol esters, complex esters and carbonate esters. Esters that can be used as a component of refrigerating machine oil are substantially all esters when polybasic acids such as dibasic acids and polyhydric alcohols are used as the acids and alcohols constituting the ester. Only partial esters are shown, and do not include partial esters in which carboxyl groups, hydroxyl groups, etc. remain without being esterified.

As the dibasic acid ester, glutaric acid,
Dibasic acids having 5 to 10 carbon atoms such as adipic acid, pimelic acid, suberic acid, azelaic acid and sebacic acid; methanol, ethanol, linear or branched propanol, linear or branched Butanol, linear or branched pentanol, linear or branched hexanol, linear or branched heptanol, linear or branched octanol, linear or branched Nonanol, linear or branched decanol, linear or branched undecanol, linear or branched dodecanol, linear or branched tridecanol, linear or branched Tetradecanol, linear or branched pentadecanol, linear or branched hexadecanol, linear or branched heptadecanol, linear or branched Octadecanol, linear or branched Nonadecanol, linear or branched icosanol, linear or branched henicosanol, linear or branched docosanol, linear or branched tricosanol and linear or branched Esters of a linear or branched alkyl group having 1 to 24 carbon atoms with a monohydric alcohol such as tetracosanol, and mixtures thereof can be used.
Ditridecyl glutarate, di-2-ethylhexyl adipate, diisodecyl adipate, ditridecyl adipate and di-2-ethylhexyl sebacate, and mixtures thereof can be used.

Among the esters used as refrigerating machine oil, the polyol ester includes a diol or a polyol having 3 to 20 hydroxyl groups and a polyol having 6 to 2 carbon atoms.
Preference is given to using esters with fatty acids which are 0. As the diol, specifically, ethylene glycol, 1,3-propanediol, propylene glycol, 1,4-butanediol, 1,2-butanediol, 2-methyl-1,3-propanediol, 1,5-
Pentanediol, neopentyl glycol, 1,6-
Hexanediol, 2-ethyl-2-methyl-1,3-
Propanediol, 1,7-heptanediol, 2-methyl-2-propyl-1,3-propanediol, 2,
2-diethyl-1,3-propanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-
There are decanediol, 1,11-undecanediol, and 1,12-dodecanediol.

Examples of the polyol having 3 to 20 hydroxyl groups include trimethylolethane, trimethylolpropane, trimethylolbutane, di- (trimethylolpropane), tri- (trimethylolpropane), pentaerythritol, Di- (pentaerythritol), tri- (pentaerythritol), glycerin, polyglycerin (glycerin dimer to 20mer),
Polyhydric alcohols such as 1,3,5-pentanetriol, sorbitol, sorbitan, sorbitol glycerin condensate, adonitol, arabitol, xylitol and mannitol, and xylose, arabinose, ribose, rhamnose, glucose, fructose, galactose, mannose, sorbose, There are sugars such as cellobiose, maltose, isomaltose, trehalose, sucrose, raffinose, gentianose, and melezitose, and partially etherified products thereof, and methyl glucoside (glycoside).

As a fatty acid having 6 to 20 carbon atoms,
Specifically, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid, octadecanoic acid, nonadecanoic acid, There are linear or branched ones such as icosanoic acid and oleic acid, and neo acids having a quaternary α-carbon atom.

More specifically, valeric acid, isopentanoic acid, capric acid, pelargonic acid, 2-methylhexanoic acid, 2-ethylpentanoic acid, caprylic acid, 2-ethylhexanoic acid, normal nonanoic acid, 3,5,5 5-trimethylhexanoic acid and the like. Some polyol esters have a free hydroxyl group. Incidentally, particularly preferably,
Neopentyl glycol, trimethylolethane, trimethylolpropane, trimethylolbutane, di- (trimethylolpropane), tri- (trimethylolpropane), pentaerythritol, di- (pentaerythritol), tri- (pentaerythritol), etc. Is an ester of hindered alcohol. Specifically, neopentyl glycol-2-ethylhexanoate, trimethylolpropane caprylate, trimethylolpropaneperargonate, pentaerythritol-2-ethylhexanoate, and pentaerythritol pelargonate, and mixtures thereof, etc. is there.

Among the esters used as refrigerator oil, complex esters are esters of fatty acids and dibasic acids with monohydric alcohols and polyols, and include esters of fatty acids, dibasic acids, monohydric alcohols and polyols. Can be the same as those exemplified for the dibasic acid ester and the polyol ester.

The carbonic acid ester is an ester of carbonic acid with a monohydric alcohol and a polyol. The monohydric alcohol and the polyol may be the same as those described above, or may be obtained by homopolymerizing or copolymerizing an alkylene oxide. Polyglycols obtained by adding polyglycol to the above-mentioned polyols and the above-mentioned polyols can be used.

The ethers usable as the refrigerating machine oil include polyglycols, polyvinyl ethers,
There are polyphenyl ether, cyclic ether, perfluoroether and the like, and among these ethers, it is preferable to use polyglycol and polyvinyl ether.

As the polyglycol, it is preferable to use a polyalkylene glycol, its etherified product, a modified compound thereof and the like. As the polyalkylene glycol, those obtained by homopolymerizing or copolymerizing an alkylene oxide such as ethylene oxide, propylene oxide, and butylene oxide can be used. In the polyalkylene glycol, when alkylene oxides having different structures are copolymerized, the polymerization form of the oxyalkylene group is not particularly limited, and may be random copolymerized or block copolymerized. .

The etherified product of polyalkylene glycol is obtained by etherifying the hydroxyl group of the above-mentioned polyalkylene glycol. As the etherified product of the polyalkylene glycol, specifically, monomethyl ether,
Monoethyl ether, monopropyl ether, monobutyl ether, monopentyl ether, monohexyl ether, monoheptyl ether, monooctyl ether,
Examples include monononyl ether, monodecyl ether, dimethyl ether, diethyl ether, dipropyl ether, dibutyl ether, dipentyl ether, dihexyl ether, diheptyl ether, dioctyl ether, dinonyl ether, and didecyl ether.

Examples of modified compounds of polyglycol include alkylene oxide adducts of polyols and etherified products thereof. As this polyol, the same polyols as those exemplified for the polyol ester can be used.

Further, as the polyvinyl ether, those having a structural unit represented by the following general formula (1) can be used.

[0075]

Embedded image Here, R ₄ , R ₅ and R ₆ each represent a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, which may be the same or different. R ₇ has 2 carbon atoms
And a divalent hydrocarbon group of 10 to 10, and R ₈ has 1 carbon atom.
To 10 hydrocarbon groups. Further, m is an integer having an average value of 0 to 10, and R _{4 to} R ₈ may be the same or different for each structural unit. Further, R ₇ -O
Are present, that is, when m is 2 or more,
A plurality of R ₇ —Os may be the same or different.

When oxygen-containing synthetic oil is used among these refrigerating machine oils, the residue in the copper pipe after annealing has a large effect on the refrigeration system. When used, a remarkable effect can be obtained.

[0077]

EXAMPLES Hereinafter, examples of the lubricating oil for copper pipe processing according to the present invention will be specifically described in comparison with comparative examples.

First, the ingot of phosphorous deoxidized copper is subjected to hot extrusion and cold rolling, and then the lubricating oil for copper pipe processing having various characteristics is used with a bull block to obtain a copper ingot having a diameter of 9. 5
A copper tube having a thickness of 2 mm and a wall thickness of 0.41 mm was drawn, and the presence or absence of seizure of the tool (plug) was evaluated. Regarding the seizure of the tool, when a predetermined number of drawing processes are performed on a small-diameter product from a large-diameter raw tube using a plug, seizure does not occur on the plug even if the total drawing length of the copper tube is 3 km. Were evaluated as ○, and those in which image sticking occurred by drawing less than 3 km were evaluated as ×.

Next, a long copper tube having a length of 2 km after drawing was used.
After being wound in a coil shape, it was annealed in a bright annealing furnace. What
Before annealing, CO gas with nitrogen gas as the main component,
CO _TwoGas and H_TwoGas containing reducing gas (DX gas
Flow) into the tube at a flow rate of 20 liters / minute for 30 minutes.
Was replaced with DX gas. In the bright annealing furnace, the minimum
The temperature section is kept at least at 450 ° C for 10 minutes
So that the temperature of the atmosphere gas is set at 600 ° C,
After heat annealing for 25 minutes, it was cooled.

Next, after the residual gas in the cooled long annealed coil copper tube was replaced with dry air, the copper tube was disassembled, and the residual oil mass at various portions in the tube was measured by the following method. First, from a coiled copper tube, 15
After taking a point sample and cutting it to a length of 10m,
Hydrochlorofluorocarbon (HCFC-141
The inner surface of the tube was washed according to b), and residual oil adhering to the inner surface was extracted. Next, after heating the residual oil to evaporate the solvent, the residual amount is measured, converted into the amount of residual oil per 1 m long copper tube, the maximum residual oil mass and the average residual oil. The mass was calculated.

Further, each of the manufactured long coil copper tubes was
Cut the two test tubes and cut one end of the test tube
After expanding the tube, insert the end of the other test tube to reduce the wire diameter.
Use 1.6mm phosphor copper brazing wire (BCuP-2)
By heating with propane combustion gas for 6 seconds.
And brazed both. And 30kg / c in the pipe
m ^TwoGas leaks when filling with chlorofluorocarbon gas at
Those that did not occur were marked as ○, and gas was
The sample in which the leakage occurred was evaluated as x.

Further, 60 g of the lubricating oils of Examples and Comparative Examples were injected into a copper tube, the ends of both tubes were crushed and annealed under the same annealing conditions as described above. In addition, both ends of the copper tube were crushed so that the inside of the tube was not completely sealed and gas inside hardly leaked to the outside. After annealing, the end of the tube was cut open, and only the outer surface was washed with acetone and n-hexane. The residual oil in the tube was extracted by ultrasonic cleaning using a 1: 1 mixed solvent of acetone and hexane. Thereafter, the extract was subjected to distillation under reduced pressure at a temperature of 40 ° C. and a pressure of 10 mmHg to remove the solvent and low-boiling components, thereby producing an annealing residue.

Thereafter, in order to investigate the effect of the obtained residual oil on the refrigeration system, JIS K2211 was used.
A shield tube test was conducted in accordance with Annex 2 “Chemical stability test method with refrigerant (shield tube test)” of “Refrigeration oil”. The detailed test conditions are shown below. First, 1 ml of refrigerant, 1 ml of sample oil, and a catalyst consisting of a metal wire having a thickness of 1.6 mm and a length of 50 mm were put into a glass tube having an inner diameter of 10 mm. Was melted and sealed. Next, after maintaining the glass tube at a temperature of 175 ° C. for 14 days, a change in the state of the liquid layer was observed. Then, as a result of the observation, a case where there was no change was evaluated as 、, and a case where deterioration of the catalyst, discoloration of the sample oil or cloudiness or a precipitate was present was evaluated as ×.

In this example, a mixture of 0.3 mg of annealing residual oil and 1.0 g of refrigerating machine oil was used as a sample oil, and a metal wire made of iron, copper, aluminum or the like was used as a catalyst. It was used. In addition, as a refrigerant,
R410A and R407C were used, and as a refrigerating machine oil, a tetraester of ester oil (pentaerythritol and a mixed fatty acid of 2-ethylhexanoic acid and 3,5,5-trimethylhexanoic acid (molar ratio 50:50) (at 40 ° C.) Kinematic viscosity: 68 mm ² / sec)) was used.

The types and properties of base oils used as components of the lubricating oil are shown in Table 1 below, and the types of partially etherified polyhydric alcohols used as components of the lubricating oil are shown in Table 2 below. Table 3 below shows the types of components added to the lubricating oil. Further, the compositions and kinematic viscosities of the lubricating oils are shown in Tables 4 and 5 below, and the evaluation results of various tests are shown in Tables 6 and 7 below.

[0086]

[Table 1]

[0087]

[Table 2]

[0088]

[Table 3]

[0089]

[Table 4]

[0090]

[Table 5]

[0091]

[Table 6]

[0092]

[Table 7]

As shown in Tables 1 to 7 above, Example N
o. In Nos. 1 to 14, the base oil and the partially etherified polyhydric alcohol are appropriately selected, so that the maximum amount of residual oil after annealing of the coiled copper tube is 0.50 mg / m or less, and poor brazing and tooling. (Plug) burn-in did not occur.

On the other hand, in Comparative Example No. In No. 15, the plug was seized at the time of drawing because the lubricating oil did not contain a partially etherified polyhydric alcohol having two or more polyhydric alcohols.
In addition, since the kinematic viscosity of the lubricating oil exceeded the upper limit of the preferred range of the present invention, the amount of residual oil in the pipe was increased as compared with the example, and leakage occurred after brazing. Comparative Example N
o. In Nos. 16 and 17, the residual oil content in the tubes was small, but the content of the partially etherified polyhydric alcohol was lower than the lower limit of the present invention. . Comparative Example No. 18 or 2
2 is because the type of base oil is out of the scope of the present invention,
The residual oil amount in the pipe after annealing increased, and poor brazing occurred. In the shield tube test, cloudiness or a precipitate was confirmed. Further, in Comparative Example No. In No. 20, the plug had seizure because the kinematic viscosity of the lubricating oil was low.

[0095]

As described in detail above, according to the present invention,
A polyalkylene glycol having a predetermined structure and / or an alkyl ether of the polyalkylene glycol;
Since the content in the lubricating oil with partially etherified polyhydric alcohols having a valency of more than 3 is appropriately regulated, a special residual oil removal treatment is applied to the long coil copper tube in the annealing furnace after drawing or rolling. , The residual oil in the pipe can be reduced at low cost, and the brazing property of the copper pipe can be improved. Further, by appropriately adjusting the kinematic viscosity of the lubricating oil, lubricity can be improved, and thereby seizure during drawing can be prevented. Further, it is possible to reduce the adverse effect of the residue after annealing on the refrigeration system.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI C10N 30:06 C10N 40:24 Z 40:24 (72) Inventor Kozo Saeki 1-5-5 Takatsukadai, Nishi-ku, Kobe City, Hyogo Prefecture No. Kobe Steel, Ltd.Kobe Integrated Technology Research Institute (72) Inventor Takeki Otsuka 1-5-5 Takatsukadai, Nishi-ku, Kobe City, Hyogo Prefecture Kobe Steel Ltd.Kobe Integrated Technology Research Institute (72) Inventor Hideo Yokota Kanagawa 8, Chidori-cho, Naka-ku, Yokohama-ku, Japan Japan Petroleum Corporation Central Technology Research Institute (72) Inventor Kazuhiko Endo 8, Chidori-cho, Naka-ku, Yokohama-shi, Kanagawa Japan Japan Petroleum Corporation Central Technology Research Institute (72) Inventor Kazuka Dai Kanagawa No. 8 Chidoricho, Naka-ku, Yokohama-shi, Japan Inside the Central Research Laboratory of Petroleum Co., Ltd. (72) Noboru Ishida 8, Chidori-cho, Naka-ku, Yokohama, Kanagawa (56) References JP-A-9-272889 (JP, A) JP-A-9-263780 (JP, A) JP-A-9-208984 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) C10M 169/04 C10M 105/18 C10M 107/34 C10M 129/16 C10M 145/26-145/38 C10N 30:00 C10N 30:06 C10N 40:24

Claims (6)

(57) [Claims] Claims: _{1. A} general formula: R ₁ -O, based on the total mass of a lubricating oil.
— (R ₂ —O) _n —R ₃ (where R ₁ and R _{3 are a} hydrogen atom or an alkyl group, R ₂ is an alkylene group having 4 to 6 carbon atoms,
n: 10 to 100), a base oil composed of at least one selected from the group consisting of polyalkylene glycols, which are homopolymers represented by the following formulas, and alkyl ethers of the polyalkylene glycols: 70 to 99.5% by mass, and , Ethylene glycol, ethylene glycol 2 to
10-mer , propylene glycol, propylene glycol
Partially etherified product of one or more dihydric or higher polyhydric alcohols selected from the group consisting of dimer to dimer , glycerin, diglycerin, triglycerin, trimethylolethane, trimethylolpropane and trimethylolbutane A lubricating oil for processing copper pipes, comprising 0.5 to 30% by mass of a mixture of partial etherified products of at least two or more polyhydric alcohols. 2. The general formula: R ₁ —O per total mass of the lubricating oil
— (R ₂ —O) _n —R ₃ (where R ₁ and R _{3 are a} hydrogen atom or an alkyl group, R ₂ is an alkylene group having 3 to 6 carbon atoms,
n: 10 to 100), a base oil consisting of at least one selected from the group consisting of polyalkylene glycols which are copolymers represented by the formula (I) and alkyl ethers of the polyalkylene glycols: 70 to 99.5% by mass, and , Ethylene glycol, ethylene glycol 2 to
10-mer , propylene glycol, propylene glycol
Partially etherified product of one or more dihydric or higher polyhydric alcohols selected from the group consisting of dimer to dimer , glycerin, diglycerin, triglycerin, trimethylolethane, trimethylolpropane and trimethylolbutane A lubricating oil for processing copper pipes, comprising 0.5 to 30% by mass of a mixture of partial etherified products of at least two or more polyhydric alcohols. 3. The lubricating oil for copper pipe processing according to claim 1, wherein the total amount of the base oil and the partially etherified product of the dihydric or higher polyhydric alcohol is 90% by mass or more. . 4. A kinematic viscosity at 40 ° C. of 50 to 200.
Copper pipe processing lubricating oil according to any one of claims 1 to 3, characterized in that it is 0 mm ² / sec. 5. The lubricating oil according to claim 1, wherein the lubricating oil is used as an internal lubricating oil for heat treatment of copper or copper alloy tubes. 6. The method according to claim 1, wherein when the copper or copper alloy tube wound in a coil shape is processed, the copper or copper alloy tube is supplied to an inner surface of the copper or copper alloy tube. The lubricating oil for copper pipe processing as described.