JP2003119482A - Lubricating oil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a lubricating oil having a low viscosity and excellent heat resistance and low-temperature fluidity. SOLUTION: This lubricating oil comprises a diester represented by formula (1) [wherein, R<1> and R<2> are each the same or different and denote each a 3-17C straight-chain alkyl group; and A denotes a residue of a 2-10C straight-chain aliphatic dihydric alcohol or a 2-10C branched-chain aliphatic dihydric alcohol having one or two branched chains, with the proviso that the two branched chains are not bound to a same carbon atom when A has the two branched chains].

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating oil, and more particularly to a lubricating oil containing an organic acid ester, which has a low viscosity and is excellent in heat resistance, such as an automobile lubricating oil, an industrial lubricating oil and a marine lubricating oil. The present invention relates to oils and the like, particularly automotive lubricating oils such as engine oils, gear oils, automatic transmission oils and shock absorber oils, as well as industrial lubricating oils such as bearing lubricating oils and refrigerator lubricating oils.

[0002]

2. Description of the Related Art In response to the recent global warming problem, high efficiency of devices has been studied in various industrial fields such as automobiles, home appliances, electronic information devices, and industrial machines. In the study of higher efficiency, various improvements have been made in the lubricating oil used, and one of the effective methods is to reduce the viscosity of the lubricating oil in order to reduce energy loss due to viscous friction. Is being promoted.

For example, in automotive applications, lubricating oil is used in various places such as engine oil, gear oil, automatic transmission oil, shock absorber oil and the like. With respect to these lubricating oils, low-viscosity lubricating oils with high lubricating performance are being studied for the purpose of improving fuel efficiency. More recently, emphasis has been placed on reducing friction during starting and at low temperatures, and there is a need for a lubricating oil that has low viscosity and low frictional resistance over a wide temperature range from room temperature to low temperature.

In the present application, mineral oil has been mainly used from the past, but in order to satisfy that the viscosity is low in a wide temperature range, a lubricating oil having a high viscosity index, that is, a synthetic hydrocarbon or an ester is required. It is necessary to use the kind. Among these, as the esters, a diester obtained from a reaction of an aliphatic dibasic acid and a monohydric alcohol (hereinafter, referred to as "aliphatic dibasic acid diester") or a neopentyl polyol (a polyhydric compound having a neopentyl type structure) alcohol)
Of a polyol obtained by the reaction of carboxylic acid with an aliphatic carboxylic acid (hereinafter referred to as "polyol ester")
The use of is known. However, when studying lowering of viscosity using such dibasic acid diesters and polyol esters, esters of smaller molecular weight are used, but under recent severe conditions of use, these low viscosity esters are However, it is becoming difficult to satisfy heat resistance, especially volatility resistance.

Lubricating oils for bearings have been used for bearings of various motors for automobiles (electrical components), home appliances (air conditioners, refrigerators, etc.), audio equipment (CD players, MD players, etc.), etc. , The demand for computer (memory motor) and mobile phone (vibration motor) is increasing rapidly. In addition, recently, the load on bearings has increased more and more with the downsizing of equipment and the speeding up of rotation of motors, and there is a demand for lubricating oils having higher performance.

The performance required of the lubricating oil for bearings is as follows.
They are excellent in heat resistance (oxidation stability, volatility resistance, and small change in viscosity), can be used in a wide temperature range, have excellent lubricity, have little influence on bearing materials, and the like. Above all, heat resistance is very important because the temperature rise is large due to the increased load on the bearing.

Up to now, poly-α has been used as a lubricating oil for bearings.
It has been disclosed that lubricating oils using synthetic hydrocarbon oils such as olefins, ester oils such as aliphatic dibasic acid diesters and polyol esters have excellent performance (Japanese Patent Laid-Open Nos. Hei 7-53984 and Hei 9). -125086
No. 11-172267). However, these lubricating oils are not sufficiently resistant to the harsh conditions of use, and when the viscosity of the lubricating oil becomes low, the heat resistance, particularly the volatility resistance, becomes poor.
We have not provided a bearing lubricant suitable for energy saving.

Lubricating oils for refrigerators are used for car air conditioners,
Lubricating oil used for compressors such as refrigerators, refrigerators, room air conditioners, and large industrial refrigerators. Conventionally, mineral oil type lubricating oil has been mainly used as the lubricating oil for the refrigerator,
From the viewpoint of the ozone layer depletion problem, CFC (chlorofluorocarbon), HCFC (hydrochlorofluorocarbon) and other chlorine-based refrigerants, HFC-134a represented by alternative CFC [HFC (hydrofluorocarbon)]
And natural refrigerants such as hydrocarbons, carbon dioxide, and ammonia are being replaced.

Due to the fact that the refrigerator uses a refrigerant, the lubricating oil for refrigerators is required to have special properties in addition to the excellent lubricity and heat resistance required for ordinary lubricating oils. It Specific examples include excellent refrigerant compatibility, excellent electric insulation, and excellent hydrolysis stability. In view of these required performances, conventional mineral oil-based lubricating oils have the drawback of poor compatibility with refrigerants, and therefore ethers or esters having excellent compatibility with refrigerants have come to be used.

Examples of ester-based refrigerating machine lubricating oils include JP-A-3-128991 and JP-A-3-2008.
As disclosed in Japanese Patent No. 95, etc., polyol esters are known. In the case of studying lowering the viscosity by using this polyol ester, an ester using a fatty acid having a smaller molecular weight is used, but there is a drawback that necessary properties such as lubricity and heat resistance are not sufficient. Therefore, there is a demand for an ester-based refrigerator lubricating oil that has a low viscosity and sufficiently satisfies the required performance.

From the viewpoint of environmental pollution, there is a growing demand for biodegradability of all lubricating oils regardless of their use. Heretofore, as biodegradable lubricating oils, in addition to vegetable oils, esters using raw materials derived from vegetable oils have been used. For example, rapeseed oil, oleic acid ester of neopentyl polyol and the like can be mentioned, but these lubricating oils have a very poor heat resistance and have a serious drawback that they are tarred and coked severely. Therefore, a lubricating oil having biodegradability and excellent heat resistance is earnestly desired.

[0012]

Under such circumstances, the present invention has a low viscosity in a wide temperature range, is excellent in heat resistance, lubricity, low temperature fluidity and has high biodegradability. Intended to provide oil.

[0013]

Means for Solving the Problems As a result of intensive studies to achieve the above objects, the present inventors have found that a lubricating oil containing a specific aliphatic diester has a low viscosity in a wide temperature range. It was Furthermore, they have found that the aliphatic diester is excellent in heat resistance and has excellent performance as a lubricating oil for various applications, and based on such findings, the present invention has been completed.

That is, the lubricating oil according to the present invention is characterized by containing a diester represented by the general formula (1). [In the formula, R ¹ and R ² are the same or different and have 3 to 3 carbon atoms.
17 represents a linear alkyl group. A represents a residue of an aliphatic dihydric alcohol having 2 to 10 carbon atoms or having 1 or 2 branched chains. However, when A has two branched chains, the two branched chains are not bound to the same carbon atom. ]

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The diester represented by the general formula (1) according to the present invention (hereinafter referred to as "the present ester") is preferably a predetermined acid component and an alcohol component in accordance with a conventional method. Is an ester compound prepared by full esterification under heating or stirring in the presence of an esterification catalyst or in the absence of a catalyst under an atmosphere of an inert gas such as nitrogen.

The acid component of the present ester is an aliphatic straight chain saturated monocarboxylic acid having 4 to 18 carbon atoms, specifically,
n-butanoic acid, n-pentanoic acid, n-hexanoic acid, n-
Heptanoic acid, n-octanoic acid, n-nonanoic acid, n-decanoic acid, n-undecanoic acid, n-dodecanoic acid, n-tridecanoic acid, n-tetradecanoic acid, n-pentadecanoic acid, n
Examples include hexadecanoic acid, n-heptadecanoic acid, and n-octadecanoic acid. Among these, excellent heat resistance,
From the viewpoint of low viscosity at low temperature, an aliphatic linear saturated monocarboxylic acid having 4 to 12 carbon atoms is preferable, and specifically, n-butanoic acid, n-pentanoic acid, n-hexanoic acid, n-heptanoic acid, n-octanoic acid, n-nonanoic acid, n-decanoic acid, n
-Undecanoic acid and n-dodecanoic acid are exemplified, and in particular, n
-Heptanoic acid, n-octanoic acid, n-nonanoic acid, n-decanoic acid are recommended.

The above-mentioned acid components can be used for esterification alone, or two or more kinds of acids can be mixed and used. When two or more kinds of acids are mixed and used for esterification, the resulting ester includes a mixed group ester containing a group derived from two or more kinds of acids in one molecule.

The alcohol component of this ester has 2 carbon atoms.
It is an aliphatic dihydric alcohol having 10 to 10 linear or 1 or 2 branched chains. However, in the case of having two branched chains, the two branched chains are not bonded to the same carbon atom. Therefore, the alcohol component of the present ester is a neopentyl glycol having a neopentyl type structure in the molecule or It does not contain neopentyl polyol such as trimethylolpropane.

As the alcohol component of the present ester, specifically, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-
Propanediol, 1,3-butanediol, 1,4-
Butanediol, 2-methyl-1,4-butanediol, 1,4-pentanediol, 1,5-pentanediol, 2-methyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,5-hexanediol, 1,6-hexanediol, 2-methyl-1,
6-hexanediol, 3-methyl-1,6-hexanediol, 1,6-heptanediol, 1,7-heptanediol, 2-methyl-1,7-heptanediol,
3-methyl-1,7-heptanediol, 4-methyl-
1,7-Heptanediol, 1,7-octanediol, 1,8-octanediol, 2-methyl-1,8-
Octanediol, 3-methyl-1,8-octanediol, 4-methyl-1,8-octanediol, 1,8
-Nonanediol, 1,9-nonanediol, 2-methyl-1,9-nonanediol, 3-methyl-1,9-nonanediol, 4-methyl-1,9-nonanediol,
5-methyl-1,9-nonanediol, 1,10-decanediol, 2-ethyl-1,3-hexanediol,
2,4-diethyl-1,5-pentanediol and the like are exemplified.

Of these, aliphatic dihydric alcohols having 4 to 6 carbon atoms and having 1 to 2 branched chains are preferable because of their excellent heat resistance and low-temperature fluidity, and specifically, 2-methyl-1 , 3-propanediol, 1,3-butanediol, 2-methyl-1,4-butanediol, 1,4-pentanediol, 2-methyl-1,5-pentanediol, 3-methyl-1,5- Pentanediol, 1,5-
Hexanediol is recommended, especially 3-methyl-1,
5-pentanediol is preferred.

When carrying out the esterification reaction, the acid component is
For example, 2.0 to 3.0 with respect to 1 mol of the alcohol component.
The amount used is preferably about 2.01 to 2.5 mol.

Examples of the esterification catalyst include Lewis acids, alkali metals, sulfonic acids, and the like. Specific examples of Lewis acids include aluminum derivatives, tin derivatives, and titanium derivatives, and examples of alkali metals include sodium alkoxides. Examples include potassium alkoxide, and examples of sulfonic acids include paratoluenesulfonic acid, methanesulfonic acid, and sulfuric acid. The amount used is, for example, 0.
It is used in an amount of about 05 to 1.0% by weight.

The esterification temperature is 150 to 230.
The temperature is exemplified, and the reaction is usually completed in 3 to 30 hours.

After completion of the esterification reaction, excess raw materials are distilled off under reduced pressure or normal pressure. Subsequently, the ester can be purified by a conventional purification method, for example, neutralization, water washing, liquid-liquid extraction, vacuum distillation, adsorption purification such as activated carbon treatment, and the like.

Among the present esters, preferred diesters are 2-methyl-1,3-propanediol,
1,3-butanediol, 2-methyl-1,4-butanediol, 1,4-pentanediol, 2-methyl-
A diester of 1,5-pentanediol, 3-methyl-1,5-pentanediol or 1,5-hexanediol and an aliphatic saturated linear monocarboxylic acid having 7 to 10 carbon atoms is exemplified.

Specific examples of preferred diesters include 2
-Methyl-1,3-propanediol and carbon number 7-10
Examples of diesters of aliphatic saturated linear monocarboxylic acids include 2-methyl-1,3-propanediol di (n-
Heptyl), 2-methyl-1,3-propanediol di (n-octyl), 2-methyl-1,3-propanediol di (n-nonyl), 2-methyl-1,3-propanediol di (n -Decyl) is exemplified.

1,3-Butanediol and C7-10
Examples of diesters of aliphatic saturated linear monocarboxylic acids include 1,3-butanediol di (n-heptyl),
1,3-butanediol di (n-octyl), 1,3-
Examples are butanediol di (n-nonyl) and 1,3-butanediol di (n-decyl).

Examples of diesters of 2-methyl-1,4-butanediol and aliphatic saturated linear monocarboxylic acids having 7 to 10 carbon atoms include 2-methyl-1,4-butanediol di (n-heptyl). ), 2-methyl-1,4-butanedioldi (n-octyl), 2-methyl-1,4-butanedioldi (n-nonyl), 2-methyl-1,4-butanedioldi (n-). Decyl) is exemplified.

1,4-Pentanediol and carbon number 7 to 1
Examples of the diester of 0 with an aliphatic saturated linear monocarboxylic acid include 1,4-pentanediol di (n-heptyl), 1,4-pentanediol di (n-octyl),
1,4-pentanediol di (n-nonyl), 1,4-
An example is pentanediol di (n-decyl).

As a diester of 2-methyl-1,5-pentanediol and an aliphatic saturated linear monocarboxylic acid having 7 to 10 carbon atoms, 2-methyl-1,5-pentanediol di (n-heptyl) can be used. ), 2-methyl-1,5-pentanediol di (n-octyl), 2-methyl-1,5
-Pentanediol di (n-nonyl), 2-methyl-
An example is 1,5-pentanediol di (n-decyl).

As a diester of 3-methyl-1,5-pentanediol and an aliphatic saturated linear monocarboxylic acid having 7 to 10 carbon atoms, 3-methyl-1,5-pentanediol di (n-heptyl) can be used. ), 3-methyl-1,5-pentanediol di (n-octyl), 3-methyl-1,5
-Pentanediol di (n-nonyl), 3-methyl-
An example is 1,5-pentanediol di (n-decyl).

1,5-hexanediol and carbon number 7 to 1
Examples of the diester of 0 with an aliphatic saturated linear monocarboxylic acid include 1,5-hexanedioldi (n-heptyl), 1,5-hexanedioldi (n-octyl),
1,5-hexanediol di (n-nonyl), 1,5-
Hexanediol di (n-decyl) is exemplified.

Among the above-mentioned preferred diesters, 3-methyl-1,5-pentanedioldi (n-heptyl) and 3-methyl-1,5-pentanedioldi (n-octyl) are excellent in heat resistance. , 3-methyl-1,5-pentanedioldi (n-nonyl), 3-methyl-1,5
-Pentanediol di (n-decyl) is preferable, and 3-methyl-1,5 is particularly preferable because it has excellent low-temperature fluidity.
-Pentanediol di (n-heptyl), 3-methyl-
1,5-Pentanediol di (n-octyl) is preferred.

Among the esters, two kinds of fatty acids selected from aliphatic saturated linear monocarboxylic acids having 7 to 10 carbon atoms, 2-methyl-1,3-propanediol, 1,
3-butanediol, 2-methyl-1,4-butanediol, 1,4-pentanediol, 2-methyl-1,5
Diesters with one dihydric alcohol selected from -pentanediol, 3-methyl-1,5-pentanediol or 1,5-hexanediol are also preferred.

Specific examples of preferred diesters using these two fatty acids include 2-methyl-1,3-propanediol.
Diester of 1,3-propanediol with n-heptanoic acid and n-octanoic acid, 2-methyl-1,3-propanediol with n-heptanoic acid and n-nonanoic acid, 2-methyl-1, 3-propanediol and n-
Diesters of heptanoic acid and n-decanoic acid, 2-methyl-1,3-propanediol and n-octanoic acid and n
-Diesters with nonanoic acid, 2-methyl-1,3-propanediol with n-octanoic acid and n-decanoic acid, 2-methyl-1,3-propanediol with n
Examples include diesters with nonanoic acid and n-decanoic acid.

Similarly, preferred diesters using two fatty acids and 1,3-butanediol include 1,3-
Diesters of butanediol and n-heptanoic acid and n-octanoic acid, diesters of 1,3-butanediol and n-heptanoic acid and n-nonanoic acid, 1,3-butanediol and n-heptanoic acid and n- Diester with decanoic acid, 1,3-butanediol and n-octanoic acid and n-
Diester with nonanoic acid, 1,3-butanediol and n
-Diesters with octanoic acid and n-decanoic acid, 1,3
Examples include diesters of butanediol with n-nonanoic acid and n-decanoic acid.

Preferred diesters using two fatty acids and 2-methyl-1,4-butanediol include 2-
Diesters of methyl-1,4-butanediol with n-heptanoic acid and n-octanoic acid, 2-methyl-1,4-
Diester of butanediol with n-heptanoic acid and n-nonanoic acid, 2-methyl-1,4-butanediol and n
Diesters with 2-heptanoic acid and n-decanoic acid, 2-methyl-1,4-butanediol with n-octanoic acid and n
-Diester with nonanoic acid, diester with 2-methyl-1,4-butanediol with n-octanoic acid and n-decanoic acid, 2-methyl-1,4-butanediol with n-nonanoic acid and n-decane An example is a diester with an acid.

Preferred diesters using two kinds of fatty acids and 1,4-pentanediol include diesters of 1,4-pentanediol and n-heptanoic acid and n-octanoic acid, and 1,4-pentanediol and n. Diesters with heptanoic acid and n-nonanoic acid, diesters with 1,4-pentanediol with n-heptanoic acid and n-decanoic acid, 1,4-pentanediol with n-octanoic acid and n
A diester of nonanoic acid, a diester of 1,4-pentanediol with n-octanoic acid and n-decanoic acid,
Examples are diesters of 1,4-pentanediol with n-nonanoic acid and n-decanoic acid.

A preferred diester using two fatty acids and 2-methyl-1,5-pentanediol is 2
Diesters of -methyl-1,5-pentanediol with n-heptanoic acid and n-octanoic acid, 2-methyl-1,
A diester of 5-pentanediol with n-heptanoic acid and n-nonanoic acid, a diester of 2-methyl-1,5-pentanediol with n-heptanoic acid and n-decanoic acid, 2-methyl-1,5- 2-Methyl-, a diester of pentanediol with n-octanoic acid and n-nonanoic acid
Examples include diesters of 1,5-pentanediol with n-octanoic acid and n-decanoic acid, and diesters of 2-methyl-1,5-pentanediol with n-nonanoic acid and n-decanoic acid.

A preferred diester using two fatty acids and 3-methyl-1,5-pentanediol is 3
A diester of -methyl-1,5-pentanediol with n-heptanoic acid and n-octanoic acid, 3-methyl-1,
A diester of 5-pentanediol with n-heptanoic acid and n-nonanoic acid, a diester of 3-methyl-1,5-pentanediol with n-heptanoic acid and n-decanoic acid, 3-methyl-1,5- A diester of pentanediol with n-octanoic acid and n-nonanoic acid, 3-methyl-
Examples include diesters of 1,5-pentanediol with n-octanoic acid and n-decanoic acid, and diesters of 3-methyl-1,5-pentanediol with n-nonanoic acid and n-decanoic acid.

Preferred diesters using two kinds of fatty acids and 1,5-hexanediol include 1,5-hexanediol and n-heptanoic acid and n-octanoic acid diesters, and 1,5-hexanediol and n-octanediol. Diesters with heptanoic acid and n-nonanoic acid, diesters with 1,5-hexanediol with n-heptanoic acid and n-decanoic acid, 1,5-hexanediol with n-octanoic acid and n
A diester of nonanoic acid, a diester of 1,5-hexanediol with n-octanoic acid and n-decanoic acid,
Examples are diesters of 1,5-hexanediol and n-nonanoic acid and n-decanoic acid.

Among the preferable diesters using the above-mentioned two kinds of fatty acids, 3-methyl-
Diesters of 1,5-pentanediol with n-heptanoic acid and n-octanoic acid, 3-methyl-1,5-pentanediol with n-heptanoic acid and n-nonanoic acid, 3-methyl-1, 5-pentanediol and n-
Diesters of heptanoic acid and n-decanoic acid, 3-methyl-1,5-pentanediol and n-octanoic acid and n
-Diesters with nonanoic acid, 3-methyl-1,5-pentanediol with n-octanoic acid and n-decanoic acid, 3-methyl-1,5-pentanediol with n
Diesters with nonanoic acid and n-decanoic acid are preferred.

The lubricating oil of the present invention contains one or more kinds of the present ester.

The total acid value of this ester is 0.1 mgK
OH / g or less, preferably 0.05 mgKOH / g or less. Total acid value is 0.1mgKOH / g
The heat resistance is improved in the following cases. The total acid value can be adjusted by neutralization.

The hydroxyl value of this ester is 5 mg KO.
H / g or less, preferably 3 mgKOH / g or less, more preferably 1 mgKOH / g or less.
When the hydroxyl value is 5 mgKOH / g or less, heat resistance is improved. The hydroxyl value can be adjusted by sufficiently reducing the remaining hydroxyl groups in the reaction step.

The sulfated ash content of this ester is 30 pp.
m or less, preferably 10 ppm or less. When the sulfated ash content is 30 ppm or less, heat resistance is improved. Sulfated ash has a low sulfated ash content as an acid and / or alcohol as a raw material of the present ester (for example, 30
When the metal catalyst is used as the catalyst, the catalyst itself and the organometallic compound derived from the catalyst can be sufficiently removed by neutralization, washing with water and adsorption purification.

The iodine value of this ester is 1 or less,
It is preferably 0.5 or less, more preferably 0.1 or less. When the iodine value is 1 or less, heat resistance is improved. The iodine value is a low iodine value as an acid and / or alcohol as a raw material of the present ester (for example,
It can be adjusted by using (0.3 or less).
It can also be adjusted by reducing a purified ester having an iodine value of 1 or more.

Among the present esters, those having a molecular weight of 320 to 400, preferably 330 to 380 are recommended because of their low kinematic viscosity at 0 ° C. and excellent heat resistance.

Among these esters, JIS-K-226
Those having a pour point of -20 ° C. or lower described in 9 are preferable, and those having a pour point of -30 ° C. or lower, and more preferably -40 ° C. or lower are most preferable because they are suitable for use at lower temperatures.

Among the present esters, JIS-K-228
The viscosity index described in 3 is 150 or more, preferably 16
It is preferably 0 or more, and more preferably 170 or more. An ester having a viscosity index of 150 or more has a low viscosity in a wide temperature range and has excellent heat resistance.

The ester of the present invention is added to the lubricating oil of the present invention in an amount of 40 to 1
It is contained in an amount of 00% by weight, preferably 60 to 100% by weight, more preferably 80 to 100% by weight.

Engine oil, gear oil, automatic transmission oil,
Fuel Absorber Oil The lubricating oil of the present invention includes engine oil, gear oil, automatic transmission oil and shock absorber oil (hereinafter referred to as “automotive lubricating oil”).
Say. ), And the present ester alone or in addition to the present ester, other lubricating base oils (hereinafter referred to as “combined base oils”).
That is, isomerization of mineral oil (hydrocarbon oil obtained by refining petroleum), poly-α-olefin, polybutene, alkylbenzene, alkylnaphthalene, and synthetic hydrocarbon obtained by the Fischer-Tropsch process. Synthetic hydrocarbon oil such as oil, animal and vegetable oil, organic acid ester, polyalkylene glycol,
One kind or two or more kinds of compounds selected from the group consisting of polyvinyl ether, polyphenyl ether, alkylphenyl ether and silicone oil can be appropriately used in combination.

Examples of the mineral oil include solvent-refined mineral oil, hydrorefined mineral oil, and wax isomerized oil.
0 kinematic viscosity at ℃ is 1.0~15mm ² / s, preferably is used which is in the range of 2.0~10.0mm ² / s.

The poly-α-olefin has 2 carbon atoms.
A polymer or a copolymer of .alpha.-olefin (for example, ethylene, propylene, 1-butene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene). The kinematic viscosity at 100 ° C. is 1.0 to 15 mm ² / s, and the viscosity index is 100.
The above are exemplified, and those having a kinematic viscosity at 100 ° C. of 1.5 to 10.0 mm ² / s and a viscosity index of 120 or more are particularly preferable.

As the polybutene, isobutylene is polymerized.
Copolymerized isobutylene with normal butylene
The kinematic viscosity at 100 ° C is 2.0-40.
mm ^TwoA wide range of / s can be mentioned.

The alkylbenzene has 1 to 4 carbon atoms.
Examples thereof include monoalkylbenzenes, dialkylbenzenes, trialkylbenzenes, tetraalkylbenzenes and the like, which have a molecular weight of 200 to 450 and which are substituted with 0 linear or branched alkyl groups.

The alkylnaphthalene has 1 to 1 carbon atoms.
Examples thereof include monoalkylnaphthalene and dialkylnaphthalene substituted with 30 linear or branched alkyl groups.

Examples of animal and vegetable oils include beef tallow, lard, palm oil, coconut oil, rapeseed oil, castor oil, sunflower oil and the like.

Organic acid esters other than the present ester include fatty acid monoester, aliphatic dibasic acid diester,
Examples include polyol esters and other esters.

The fatty acid monoester has 5 to 5 carbon atoms.
Examples thereof include esters of 22 aliphatic straight-chain or branched-chain monocarboxylic acids and C3-C22 straight-chain or branched-chain saturated or unsaturated aliphatic alcohols.

Examples of the aliphatic dibasic acid diester include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid,
Pimelic acid, suberic acid, azelaic acid, sebacic acid,
Aliphatic dibasic acids such as 1,9-nonamethylenedicarboxylic acid and 1,10-decamethylenedicarboxylic acid, or their anhydrides, and linear or branched, saturated or unsaturated aliphatic groups having 3 to 22 carbon atoms. Full ester with alcohol is mentioned.

Examples of the polyol ester include neopentyl glycol, trimethylolpropane, pentaerythritol, ditrimethylolpropane, dipentaerythritol, etc., and a penentol polyol having 3 to 22 carbon atoms.
It is possible to use the full-esters of linear and / or branched saturated or unsaturated fatty acids of.

Other esters include dimer acid,
Examples thereof include esters of polymerized fatty acids such as hydrogenated dimer acid and a linear or branched saturated or unsaturated aliphatic alcohol having 3 to 22 carbon atoms.

Examples of the polyalkylene glycol include ring-opening polymers of alcohol and linear or branched alkylene oxide having 2 to 4 carbon atoms. Examples of the alkylene oxide include ethylene oxide, propylene oxide, and butylene oxide, and a polymer using one of these or a copolymer using a mixture of two or more thereof can be used. Further, a compound in which the hydroxyl groups at one end or both ends are etherified or esterified can also be used. The kinematic viscosity of the polymer is 5.0 to 10
00 mm ² / s (40 ° C.), preferably 5.0 to 500
mm ² / s (40 ° C.).

The polyvinyl ether is a compound obtained by polymerizing a vinyl ether monomer, and the monomer includes methyl vinyl ether, ethyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, sec-butyl vinyl ether, tert-butyl vinyl ether,
Examples thereof include n-pentyl vinyl ether, n-hexyl vinyl ether, 2-methoxyethyl vinyl ether and 2-ethoxyethyl vinyl ether. The kinematic viscosity of the polymer is 5.0 to 1000 mm ² / s (40 ° C.),
It is preferably 5.0 to 500 mm ² / s (40 ° C.).

Examples of the polyphenyl ether include compounds having a structure in which the meta positions of two or more aromatic rings are linked by an ether bond or a thioether bond. Specifically, bis (m-phenoxyphenyl) ether, m Examples thereof include bis (m-phenoxyphenoxy) benzene and thioethers (commonly called C-ether) in which one or more oxygen atoms thereof are substituted with sulfur.

Examples of the alkyl phenyl ether include compounds obtained by substituting polyphenyl ether with a linear or branched alkyl group having 6 to 18 carbon atoms, and particularly alkyl diphenyl ether substituted with one or more alkyl groups. preferable.

Examples of the silicone oil include dimethyl silicone, methylphenyl silicone, and modified silicone such as long-chain alkyl silicone and fluorosilicone.

When these combination base oils are used in the lubricating oil of the present invention, the content thereof is 5 to 60 relative to the lubricating oil.
Weight percent is recommended.

Among these combined base oils, organic acid esters are preferable in view of excellent heat resistance and lubricity, and aliphatic dibasic acid diesters and polyol esters are particularly preferable.

Particularly preferred aliphatic dibasic acid diesters are adipic acid, azelaic acid or sebacic acid,
Illustrative examples are aliphatic saturated linear monohydric alcohols having 8 to 10 carbon atoms or full esters with aliphatic saturated branched monohydric alcohols having 8 to 13 carbon atoms. Specifically, di (n-octyl) adipate, di (n-nonyl) adipate, di (n-decyl) adipate, di (2-ethylhexyl) adipate, diisooctyl adipate, diisononyl adipate, adipine Acid di (3,5,5-trimethylhexyl), diisodecyl adipate, diisoundecyl adipate, diisododecyl adipate, diisotridecyl adipate, di (n-octyl) azelate, di (n-nonyl) azelate, diazelaate (N-decyl), di (2-ethylhexyl) azelate, diisooctyl azelate, diisononyl azelate,
Azelaic acid di (3,5,5-trimethylhexyl),
Diisodecyl azelate, diisoundecyl azelate, diisododecyl azelate, diisotridecyl azelate, di (n-octyl) sebacate, di (n-nonyl) sebacate, di (n-decyl) sebacate,
Di (2-ethylhexyl) sebacate, diisooctyl sebacate, diisononyl sebacate, di (3,5,5-trimethylhexyl sebacate), diisodecyl sebacate, diisoundecyl sebacate, diisododecyl sebacate, and diisotridecyl sebacate are preferable.

Among these, di (2-ethylhexyl) adipate, diisononyl adipate, di (3,5,5-trimethylhexyl) adipate, diisodecyl adipate, and adipine are preferred because of their excellent low-temperature fluidity of the mixed oil. Acid diisotridecyl, azelaic acid di (2-ethylhexyl), azelaic acid diisononyl, azelaic acid di (3,5,5-trimethylhexyl), azelaic acid diisodecyl, azelaic acid diisotridecyl, sebacic acid di (2-ethylhexyl), sebacic acid diisononyl , Di (3,5,5-trimethylhexyl) sebacate, diisodecyl sebacate, and diisotridecyl sebacate are most preferred.

As a particularly preferred polyol ester, a full ester of neopentyl glycol, trimethylolpropane, pentaerythritol or dipentaerythritol and a linear and / or branched chain fatty acid having 4 to 10 carbon atoms is used. It is illustrated. Specifically, one or more polyhydric alcohols selected from neopentyl glycol, trimethylolpropane, pentaerythritol or dipentaerythritol, and n-butanoic acid, n-pentanoic acid, n-hexanoic acid, n -Heptanoic acid, n-octanoic acid, n-nonanoic acid, n-decanoic acid,
Isobutanoic acid, isopentanoic acid, isohexanoic acid, isoheptanoic acid, isooctanoic acid, 2-ethylhexanoic acid,
Full esters obtained from one or more aliphatic monocarboxylic acids selected from isononanoic acid, 3,5,5-trimethylhexanoic acid and isodecanoic acid are preferred.

Among these, diesters of neopentyl glycol and linear and / or branched chain fatty acids having 5 to 10 carbon atoms are most preferable in terms of excellent low temperature fluidity of the mixed oil.

When an aliphatic dibasic acid diester and / or a polyol ester is used in combination as a base oil for combination with the lubricating oil for automobiles according to the present invention, its content is recommended to be 10 to 60% by weight based on the lubricating oil. %, And particularly preferably 20 to 40% by weight.

In order to improve the performance of the automobile lubricating oil according to the present invention, an antioxidant, a metal detergent, an ashless dispersant, an oiliness agent, an antiwear agent, an extreme pressure agent, a metal deactivator,
It is also possible to appropriately mix one or more additives such as a rust preventive agent, a viscosity index improver, a pour point depressant, and an antifoaming agent. The blending amount is not particularly limited as long as it has a predetermined effect, but a specific example thereof is shown below.

As the antioxidant, 2,6-di-ter is used.
Phenol-based compounds such as t-butyl-p-cresol, 4,4′-methylenebis-2,6-di-tert-butylphenol, N-phenyl-α-naphthylamine, p, p ′
-Amine-based compounds such as dioctyldiphenylamine and sulfur-based compounds such as phenothiazine can be used. These antioxidants are usually used in 0.01% of lubricating oil for automobiles.
˜5% by weight, preferably 0.05 to 3% by weight.

Examples of the metal detergent include Ca-petroleum sulfonate, overbased Ca-petroleum sulfonate, Ca-alkylbenzene sulfonate, overbased Ca-alkylbenzene sulfonate, Ba-alkylbenzene sulfonate and overbased Ba. -Alkylbenzene sulfonate, Mg-alkylbenzene sulfonate, overbased Mg-alkylbenzene sulfonate, Na-
Metal sulfonates such as alkylbenzene sulfonates, overbased Na-alkylbenzene sulfonates, Ca-alkylnaphthalene sulfonates, overbased Ca-alkylnaphthalene sulfonates, Ca-phenates, overbased Ca-phenates, Ba Metal phenates, such as phenates, overbased Ba-phenates,
Metal salicylates such as Ca-salicylate and overbased Ca-salicylate, Ca-phosphonates, overbased Ca-phosphonates, Ba-phosphonates,
Metal phosphonates such as overbased Ba-phosphonates and overbased Ca-carboxylates can be used. These metal detergents are usually added in an amount of 1 to 10% by weight, preferably 2 to 7% by weight, based on the lubricating oil for automobiles.

As the ashless dispersant, polyalkenyl succinimide, polyalkenyl succinamide, polyalkenyl benzylamine, polyalkenyl succinic acid ester and the like can be used. These ashless dispersants are usually
1 to 10% by weight, preferably 2 with respect to automobile lubricating oil
It is recommended to add ~ 7% by weight.

As the oiliness agent, aliphatic saturated and unsaturated monocarboxylic acids such as stearic acid and oleic acid, polymerized fatty acids such as dimer acid and hydrogenated dimer acid, hydroxy fatty acids such as ricinoleic acid and 12-hydroxystearic acid, Aliphatic saturated and unsaturated monoalcohols such as lauryl alcohol and oleyl alcohol, aliphatic saturated and unsaturated monoamines such as stearylamine and oleylamine, and aliphatic saturated and unsaturated monocarboxylic acid amides such as lauric acid amide and oleic acid amide Can be used. These oiliness agents are usually used in an amount of 0.01% by weight to 5% by weight, preferably 0.1% by weight, based on the lubricating oil for automobiles.
It is recommended to add ~ 3% by weight.

Antiwear agents / extreme pressure agents include tricresyl phosphate, cresyl diphenyl phosphate, alkylphenyl phosphates, tributyl phosphate, dibutyl phosphate and other phosphoric acid esters, tributyl phosphite, dibutyl phosphite, triisopropyl Phosphites such as phosphites and phosphorus compounds such as amine salts thereof, sulfurized fats and oils, sulfurized fatty acids such as sulfurized oleic acid, sulfur compounds such as dibenzyl disulfide, sulfurized olefins and dialkyl disulfides, Zn-dialkyldithiophosphates , Zn-dialkyldithiophosphate, Mo-dialkyldithiophosphate, Mo-dialkyldithiocarbamate, and other organometallic compounds can be used. These antiwear agents are usually used in an amount of 0.01% by weight to 1% based on the lubricating oil for automobiles.
It is recommended to add 0% by weight, preferably 0.1% to 5% by weight.

As the metal deactivator, benzotriazole type, thiadiazole type, gallic acid ester type compounds and the like can be used. These metal deactivators are usually used.
It is preferable to add 0.01 to 0.4% by weight, preferably 0.01 to 0.2% by weight, to the lubricating oil for automobiles.

Examples of the rust preventive agent include dodecenyl succinic acid half ester, octadecenyl succinic anhydride, dodecenyl succinic acid amide and other alkyl or alkenyl succinic acid derivatives, sorbitan monooleate, glycerin monooleate, pentaerythritol monooleate. Partial ester of polyhydric alcohol such as Ca-petroleum sulfonate, Ca-alkylbenzene sulfonate, Ba-
Alkylbenzene sulfonate, Mg-alkylbenzene sulfonate, Na-alkylbenzene sulfonate, Zn-alkylbenzene sulfonate, Ca
-Metal sulfonates such as alkylnaphthalene sulfonate, amines such as rosin amine and N-oleyl sarcosine, dialkyl phosphite amine salts and the like can be used. These rust preventives are usually used in an amount of 0.01% by weight to 5% by weight, preferably 0.0% by weight, of the lubricating oil for automobiles.
It is preferable to add 5 to 2% by weight.

Examples of the viscosity index improver include olefin copolymers such as polyalkylmethacrylate, polyalkylstyrene, polybutene, ethylene-propylene copolymer, styrene-diene copolymer and styrene-maleic anhydride copolymer. These viscosity index improvers are usually used in an amount of 0.1 to 1 with respect to the lubricating oil for automobiles.
It is preferable to add 5% by weight, preferably 0.5 to 7% by weight.

As the pour point depressant, a condensate of chlorinated paraffin and alkylnaphthalene, a condensate of chlorinated paraffin and phenol, and the above-mentioned viscosity index improvers such as polyalkylmethacrylate, polyalkylstyrene and polybutene are used. It is possible, and these pour point depressants are usually added in an amount of 0.01 to 5% by weight, preferably 0.1 to 3% by weight, based on the lubricating oil for automobiles.

As the defoaming agent, liquid silicone is suitable, and is usually 0.0005 to 5 with respect to the lubricating oil for automobiles.
It is better to add 0.01% by weight.

The engine oil, gear oil, automatic transmission oil and shock absorber oil according to the present invention have heat resistance equal to or higher than that of conventionally known lubricating oil, and have low kinematic viscosity at low temperature. Excellent low temperature fluidity.

Bearing Lubricating Oil The lubricating oil of the present invention can be used as a bearing lubricating oil. When used as a lubricating oil for bearings, it is possible to use the present ester alone or to use other combined base oils in the present ester. Specific examples of the combination base oil are the same as those described in the above-mentioned engine oil, gear oil, automatic transmission oil and shock absorber oil, and one kind or two or more kinds of compounds selected from them are appropriately used in combination. be able to.

When these combined base oils are used in the bearing lubricating oil of the present invention, the content thereof is 5 with respect to the lubricating oil.
~ 60 wt% is recommended.

Among the combined base oils, organic acid esters are preferable in that they are excellent in heat resistance and lubricity, and further, fatty acid monoesters and aliphatic dibasic acids are particularly preferable in view of excellent balance between heat resistance and low temperature viscosity. Diesters and polyol esters are preferred.

Particularly preferred fatty acid monoesters are aliphatic straight chain monocarboxylic acids having 12 to 18 carbon atoms and saturated aliphatic straight chain monohydric alcohols having 8 to 10 carbon atoms or aliphatic straight chain monocarboxylic acids having 8 to 13 carbon atoms. Full esters with saturated branched monohydric alcohols are exemplified. Specifically, n-octyl n-dodecanoate, n-nonyl n-dodecanoate, n-decyl n-dodecanoate, 2-ethylhexyl n-dodecanoate, isooctyl n-dodecanoate, isononyl n-dodecanoate, n -3,5,5-trimethylhexyl dodecanoate, isodecyl n-dodecanoate, isoundecyl n-dodecanoate, isododecyl n-dodecanoate, isotridecyl n-dodecanoate, n-nonyl n-tetradecanoate, n
-Tetradecanoic acid n-decyl, n-tetradecanoic acid 2-
Ethylhexyl, n-isooctyl tetradecanoate, n
-Isononyl tetradecanoate, n-tetradecanoic acid 3,
5,5-Trimethylhexyl, isodecyl n-tetradecanoate, isoundecyl n-tetradecanoate, isododecyl n-tetradecanoate, isotridecyl n-tetradecanoate, n-nonyl hexadecanoate, n-decyl n-hexadecanoate, n-hexadecane 2-ethylhexyl acid, isooctyl n-hexadecanoate, isononyl n-hexadecanoate, 3,5,5-trimethylhexyl n-hexadecanoate, isodecyl n-hexadecanoate, n
-Isoundecyl hexadecanoate, isododecyl n-hexadecanoate, isotridecyl n-hexadecanoate, n
-N-nonyl octadecanoate, n-octadecanoate n-
Decyl, 2-ethylhexyl n-octadecanoate, n-
Isooctyl octadecanoate, isononyl n-octadecanoate, 3,5,5-trimethylhexyl n-octadecanoate, isodecyl n-octadecanoate, isoundecyl n-octadecanoate, isododecyl n-octadecanoate, and isotridecyl n-octadecanoate are preferred.

Among these, 2-ethylhexyl n-dodecanoate, isooctyl n-dodecanoate, isononyl n-dodecanoate, and n-dodecanoic acid 3 are excellent in low temperature fluidity of the mixed oil and low in low temperature viscosity. , 5,5-Trimethylhexyl, isodecyl n-dodecanoate, 2-ethylhexyl n-tetradecanoate, isooctyl n-tetradecanoate, isononyl tetradecanoate, 3,5,5-trimethylhexyl n-tetradecanoate, n-tetradecane Most preferred is isodecyl acid.

Particularly preferred aliphatic dibasic acid diesters are adipic acid, azelaic acid or sebacic acid,
Illustrative examples are aliphatic saturated linear monohydric alcohols having 8 to 10 carbon atoms or full esters with aliphatic saturated branched monohydric alcohols having 8 to 13 carbon atoms. Specifically, di (n-octyl) adipate, di (n-nonyl) adipate, di (n-decyl) adipate, di (2-ethylhexyl) adipate, diisooctyl adipate, diisononyl adipate, adipine Acid di (3,5,5-trimethylhexyl), diisodecyl adipate, diisoundecyl adipate, diisododecyl adipate, diisotridecyl adipate, di (n-octyl) azelate, di (n-nonyl) azelate, diazelaate (N-decyl), di (2-ethylhexyl) azelate, diisooctyl azelate, diisononyl azelate,
Azelaic acid di (3,5,5-trimethylhexyl),
Diisodecyl azelate, diisoundecyl azelate, diisododecyl azelate, diisotridecyl azelate, di (n-octyl) sebacate, di (n-nonyl) sebacate, di (n-decyl) sebacate,
Di (2-ethylhexyl) sebacate, diisooctyl sebacate, diisononyl sebacate, di (3,5,5-trimethylhexyl sebacate), diisodecyl sebacate, diisoundecyl sebacate, diisododecyl sebacate, and diisotridecyl sebacate are preferable.

Among these, di (2-ethylhexyl) adipate, diisononyl adipate, di (3,5,5-trimethylhexyl) adipate, diisodecyl adipate, and adipine are preferred because of their excellent low temperature fluidity of the mixed oil. Acid diisotridecyl, azelaic acid di (2-ethylhexyl), azelaic acid diisononyl, azelaic acid di (3,5,5-trimethylhexyl), azelaic acid diisodecyl, azelaic acid diisotridecyl, sebacic acid di (2-ethylhexyl), sebacic acid diisononyl , Di (3,5,5-trimethylhexyl) sebacate, diisodecyl sebacate, and diisotridecyl sebacate are most preferred.

Further, as a particularly preferred polyol ester, a full ester of neopentyl glycol, trimethylolpropane, pentaerythritol or dipentaerythritol and a linear and / or branched chain fatty acid having 4 to 10 carbon atoms is used. It is illustrated. Specifically, one or more polyhydric alcohols selected from neopentyl glycol, trimethylolpropane, pentaerythritol or dipentaerythritol, and n-butanoic acid, n-pentanoic acid, n-hexanoic acid, n -Heptanoic acid, n-octanoic acid, n-nonanoic acid, n-decanoic acid,
Isobutanoic acid, isopentanoic acid, isohexanoic acid, isoheptanoic acid, isooctanoic acid, 2-ethylhexanoic acid,
Full esters obtained from one or more aliphatic monocarboxylic acids selected from isononanoic acid, 3,5,5-trimethylhexanoic acid and isodecanoic acid are preferred.

Among these, diesters of neopentyl glycol and linear and / or branched chain fatty acids having 4 to 10 carbon atoms are most preferable in terms of excellent low temperature fluidity of the mixed oil.

When a fatty acid monoester, an aliphatic dibasic acid ester and / or a polyol ester is used in combination with the lubricating oil for bearing according to the present invention as a base oil for combined use, the content thereof is 10 to the lubricating oil. 60% by weight is recommended, with 20-40% by weight being particularly preferred.

In order to improve the performance of the lubricating oil for bearings according to the present invention, an antioxidant, an oiliness agent, an antiwear agent, an extreme pressure agent, a metal deactivator, a rust preventive agent and a viscosity index improver are included. ,
One or more additives such as pour point depressants and antifoaming agents can be appropriately blended. Incidentally, specific examples and blending amounts of these additives are the same as those described in the above-mentioned automobile lubricating oil.

The bearing lubricating oil according to the present invention has heat resistance equal to or higher than that of conventionally known lubricating oil, has low kinematic viscosity at low temperature, and has excellent low temperature fluidity.

The bearing lubricating oil of the present invention can be used in various bearing devices, and is suitable for use in sintered oil-impregnated bearings and fluid bearings. Furthermore, the lubricating oil for bearings of the present invention can be used for bearings of various materials. Specific examples include iron-based bearings, copper-based bearings, lead-based bearings, and the like.

Lubricating Oil for Refrigerator Further, the lubricating oil of the present invention can be used as a lubricating oil for refrigerator. When used as a lubricating oil for a refrigerator, electric insulation, compatibility with a refrigerant, and hydrolysis stability are particularly important properties.

The refrigerating machine lubricating oil of the present invention preferably has a volume resistivity of 1 × 10 ¹¹ Ω · cm or more, particularly 1 × 10 ¹² Ω · cm or more, more preferably 1 × 10 ¹² Ω · cm or more.
It is recommended is × ^{10 13} Ω · cm or more. When the volume resistivity is less than 10 ¹¹ Ω · cm, it becomes difficult to obtain good electric insulation.

The lubricating oil for a refrigerator of the present invention has a two-layer separation temperature from the refrigerant of 10 ° C or lower, preferably 0 ° C or lower, more preferably -10 ° C or lower.

The lubricating oil for refrigerator of the present invention has a water content of 100 ppm or less, preferably 50 ppm or less. If the water content is less than 100ppm,
Good hydrolytic stability is obtained. The water content of the lubricating oil can usually be adjusted by dehydration treatment under heating and reduced pressure.

In the refrigerator lubricating oil according to the present invention, it is possible to use the present ester alone or to use another concomitant base oil with the present ester. Specific examples of the combination base oil are the same as those described in the above-mentioned automobile lubricating oil and bearing lubricating oil, and one kind or two or more kinds of compounds selected from them can be appropriately used in combination.

Among the base oils used in combination, neopentyl glycol and carbon number 4 are used because of their low viscosity and excellent balance of refrigerant compatibility, electric insulation and hydrolysis stability of the mixed oil.
Diesters with linear and / or branched fatty acids of 10 are preferred.

In order to improve the performance of the lubricating oil for a refrigerator according to the present invention, one of additives such as an antioxidant, an antiwear agent, a metal deactivator, an antifoaming agent and a hydrolysis inhibitor is added. It is also possible to appropriately mix one kind or two or more kinds. The blending amount is not particularly limited as long as it has a predetermined effect, but a specific example thereof is shown below.

As the antioxidant, 2,6-di-ter is used.
Phenol-based compounds such as t-butyl-p-cresol, 4,4′-methylenebis-2,6-di-tert-butylphenol, N-phenyl-α-naphthylamine, p, p ′
-Amine-based compounds such as dioctyldiphenylamine and sulfur-based compounds such as phenothiazine can be used. These antioxidants are usually added to the refrigerator lubricating oil in an amount of 0.01
˜5 wt%, preferably 0.1 to 2 wt%.

As the antiwear agent, phosphates such as tricresyl phosphate, cresyl diphenyl phosphate, alkylphenyl phosphates, tributyl phosphate, dibutyl phosphate, tributyl phosphite, dibutyl phosphite, triisopropyl phosphite and the like can be used. Phosphorous acid esters and their amine salts can be used. These antiwear agents are usually added in an amount of 0.01 to 5% by weight, preferably 0.01 to 2% by weight, based on the lubricating oil for the refrigerator.

As the metal deactivator, benzotriazole-based or thiadiazole-based compounds can be used.
These metal deactivators are usually used in an amount of 0.01 to 0.4% by weight, preferably 0.01 to 0.
It is recommended to add 2% by weight.

Liquid silicone is suitable as an antifoaming agent, and is usually 0.0005 to 5 with respect to the lubricating oil for refrigerators.
It is better to add 0.01% by weight.

As the hydrolysis inhibitor, epoxy compounds such as alkyl glycidyl ether, alkylene glycol glycidyl ether, phenyl glycidyl ether, alicyclic epoxies and epoxidized vegetable oil can be used. These hydrolysis inhibitors are generally used in an amount of 0.05 to 5% by weight, preferably 0.1% to the lubricating oil for refrigerators.
It is preferable to add 2 to 2% by weight.

The refrigerating machine lubricating oil according to the present invention can be used as a refrigerating machine lubricating oil using various refrigerants. As the refrigerant of these refrigerators, hydrocarbon-based refrigerants, halogen-containing hydrocarbon-based refrigerants, fluorine-containing ether-based refrigerants such as perfluoroethers, non-fluorine-containing ethers such as dimethyl ether, carbon dioxide, ammonia, etc., or these Is used.

The lubricating oil of the present invention preferably has a kinematic viscosity at 40 ° C. of 5 to 32 mm ² / s, particularly 4
The kinematic viscosity at 0 ° C. is preferably 5 to 22 mm ² / s. Moreover, kinematic viscosity at 40 ° C. in terms of power conservation is 5 to 10 mm ² / s, and 0 kinematic viscosity at ° C. is 15 to 40 mm ² / s, in particular, 15 to 35 mm ² /
It is preferably s.

[0115]

The present invention will be described in detail below with reference to examples, but the present invention is not limited to the examples. The physical properties and chemical properties of the lubricating oil in each example were evaluated by the following methods.

Total acid value Measured according to JIS-K-2501.

Kinematic viscosity : 0 ° C, 40 ° C, 10 in accordance with JIS-K-2283.
The kinematic viscosity at 0 ° C was measured.

Viscosity index Calculated according to JIS-K-2283.

Low temperature fluidity test The pour point was measured according to JIS-K-2269.

The heat resistance test of a lubricating oil is usually conducted by adding an additive such as an antioxidant. The lubricating oil and the comparative oil were also blended with the same additives and subjected to a heat resistance test.

Heat resistance test 0.5% by weight of 2,6-di-tert-butyl-p-cresol was added to and dissolved in each ester of Examples and Comparative Examples to obtain a lubricating oil (hereinafter Was referred to as "added oil"). Next, inner diameter 53mm, height 5
Add 2 g of the above added oil to a 6 mm 50 mL beaker, and
Cover with a 0 mL beaker, then in an oven at 150 ° C for 2
Heated for 4 hours. After the test, the volatilization amount of the added oil [% = (weight before test−weight after test) / weight before test × 100] was measured, and it was judged that the smaller the volatilization amount, the better the heat resistance.

Electrical Insulation Test In accordance with JIS-C-2201, the volume resistivity was 25
It was measured at ° C.

Refrigerant compatibility test According to JIS-K-2211, the sample oil and the refrigerant (HFC-134a) were added so that the sample oil would be 10% by weight, and the two-layer separation temperature at -50 to 38 ° C. Was measured. The lower the temperature, the better the compatibility between the sample oil and the refrigerant.

Hydrolysis stability test In a glass test tube having an inner diameter of 6.6 mm and a height of 30 cm, 5.0 g of a sample ester having a water content adjusted to about 500 ppm is weighed. The test tube is sealed while degassing with an aspirator, placed in an oven and heated at 175 ° C. for 24 hours. After that, the sample ester was taken out, the total acid value was measured, and it was judged that the less the increase in the total acid value, the better the hydrolysis stability.

Biodegradability test The biodegradability was based on the modified MITI method, sample oil, comparative oil 3
To 0 mg of each, 300 mL of the basic culture solution and 30 ppm of activated sludge as solid content (wastewater from an urban sewage treatment plant was acclimated with artificial sewage) were added, and 28 at 25 ° C.
After stirring for a day, the biological oxygen consumption (BOD) was measured with a coulometer (manufactured by Okura Electric Co., Ltd.), and the ratio to the theoretical consumption (total oxygen consumption: TOD) [(BOD / TOD) x 1
00:%] was defined as the biodegradation rate. The biodegradation rate in this test is 6
Those with 0% or more were judged to have good biodegradability. In order to confirm the biodegradability of activated sludge, the standard substance aniline was 40% or more on the 7th day and 6% on the 14th day.
An effective biodegradability test was conducted only when the decomposition rate was 5% or more.

Production Example 1 445.0 g of n-octanoic acid was placed in a one-liter four-necked flask equipped with a stirrer, a thermometer, and a water fractionation receiver with a cooling tube.
(3.09 mol), 177 g (1.5 mol) of 3-methyl-1,5-pentanediol, xylene (5% by weight relative to the total amount of acid and alcohol) and tin oxide (as a total amount of acid and alcohol) as a catalyst. 0.2% by weight) was charged, and the temperature was raised to 220 ° C. under reduced pressure. The esterification reaction was carried out for about 4 hours while removing the water produced with a theoretically possible amount of water (54 g) with a moisture fractionation receiver. After completion of the reaction, excess acid was removed by distillation. Then
After completion of the reaction, the solution was neutralized with an aqueous solution of caustic soda in excess of the total acid value, and then washed with water until it became neutral. Then, activated carbon treatment was carried out and further filtration was carried out to obtain 505 g of 3-methyl-1,5-pentanedioldi (n-octyl). The total acid value of the obtained ester was 0.01 mgKOH / g.

Production Example 2 401.7 g of n-heptanoic acid instead of n-octanoic acid
By the same method as in Production Example 1 except that (3.09 mol) was used, 496 g of 3-methyl-1,5-pentanediol di (n-heptyl) was obtained. The total acid value of the obtained ester was 0.01 mgKOH / g.

Production Example 3 80.3 g of n-heptanoic acid instead of n-octanoic acid
(0.618 mol) and n-octanoic acid 356.0 g
(2.472 mol) (n-heptanoic acid: n-octanoic acid = 20: 80) was used and 3-methyl-1,5-pentanediol and n were prepared in the same manner as in Production Example 1.
-Ester (A) 50 with heptanoic acid and n-octane
3 g was obtained. The total acid value of the obtained ester is 0.01 mg KO
It was H / g.

Production Example 4 200.9 g of n-heptanoic acid instead of n-octanoic acid
(1.545 mol) and n-octanoic acid 222.5 g
(1.545 mol) (n-heptanoic acid: n-octanoic acid = 50: 50) was used in the same manner as in Production Example 1 except for using 3-methyl-1,5-pentanediol and n.
-Esters with heptanoic acid and n-octanoic acid (B) 5
00g was obtained. The total acid value of the obtained ester is 0.01 mg.
It was KOH / g.

Production Example 5 200.9 g of n-heptanoic acid instead of n-octanoic acid
(1.545 mol) and 244.1 g of n-nonanoic acid
(1.545 mol) (n-heptanoic acid: n-nonanoic acid =
50:50) except that 3-methyl-1,5-pentanediol and n- were prepared in the same manner as in Production Example 1.
508 g of ester with heptanoic acid and n-nonanoic acid were obtained. The total acid value of the obtained ester was 0.01 mgKOH / g.

Production Comparative Example 1 Neopentyl glycol di () was prepared in the same manner as in Production Example 1 except that 156 g (1.5 mol) of neopentyl glycol was used instead of 3-methyl-1,5-pentanediol. 500 g of n-octyl) was obtained. The total acid value of the obtained ester was 0.01 mgKOH / g.

Preparation Comparative Example 2 401.7 g of n-heptanoic acid instead of n-octanoic acid
(3.09 mol), instead of 3-methyl-1,5-pentanediol, neopentyl glycol 156 g
Neopentyl glycol di (n-heptyl) was produced in the same manner as in Production Example 1 except that (1.5 mol) was used.
463 g was obtained. The total acid value of the obtained ester is 0.01
It was mgKOH / g.

Preparation Comparative Example 3 488.2 g of n-nonanoic acid instead of n-octanoic acid
(3.09 mol), instead of 3-methyl-1,5-pentanediol, neopentyl glycol 156 g
Neopentyl glycol di (n-nonyl) 6 was prepared in the same manner as in Production Example 1 except that (1.5 mol) was used.
11 g were obtained. The total acid value of the obtained ester is 0.01 mg.
It was KOH / g.

Production Example 6 3-Methyl-1,5-pentanedioldi (n-octyl) and di (2-ethylhexyl) sebacate obtained in Production Example 1 ("Sanso Sizer DOS" manufactured by Shin Nippon Rika)
80:20 (weight ratio) were mixed to obtain a mixed oil 1. The total acid value of the mixed oil 1 was 0.01 mgKOH / g.

Production Example 7 3-Methyl-1,5-pentanediol di (n-octyl) and neopentyl glycol mixed fatty acid ester (n-octanoic acid: n-decanoic acid = 6) obtained in Production Example 1
0:40) at a ratio of 60:40 (weight ratio), and mixed oil 2
Got The total acid value of the mixed oil 2 was 0.01 mgKOH / g.

Production Example 8 The 3-methyl-1,5-pentanediol di (n-heptyl) obtained in Production Example 2 and 2-ethylhexyl n-tetradecanoate were mixed at 70:30 (weight ratio) and mixed. Oil 3 was obtained. The total acid value of the mixed oil 3 was 0.01 mgKOH / g.

Example 1 The results of kinematic viscosity, viscosity index, low temperature fluidity test and heat resistance test of 3-methyl-1,5-pentanedioldi (n-octyl) obtained in Production Example 1 are shown in Table 1. Shown in.

[0138]

Example 2 The results of kinematic viscosity, viscosity index, low temperature fluidity test and heat resistance test of 3-methyl-1,5-pentanedioldi (n-heptyl) obtained in Production Example 2 are shown in Table 1. Shown in.

Example 3 Kinematic viscosity, viscosity index and low temperature fluidity test of ester (A) of 3-methyl-1,5-pentanediol and n-heptanoic acid and n-octanoic acid obtained in Production Example 3 The results of the heat resistance test are shown in Table 1.

Example 4 Kinematic viscosity, viscosity index, low temperature fluidity test of ester (B) of 3-methyl-1,5-pentanediol and n-heptanoic acid and n-octanoic acid obtained in Production Example 4 The results of the heat resistance test are shown in Table 1.

Example 5 Kinematic viscosity, viscosity index, low temperature fluidity test, heat resistance of the ester of 3-methyl-1,5-pentanediol and n-heptanoic acid and n-nonanoic acid obtained in Production Example 5 The test results are shown in Table 1.

Example 6 Table 1 shows the results of the kinematic viscosity, viscosity index, low temperature fluidity test and heat resistance test of the mixed oil 1 obtained in Production Example 6.

Example 7 The results of the kinematic viscosity, viscosity index, low temperature fluidity test and heat resistance test of the mixed oil 2 obtained in Production Example 7 are shown in Table 1.

Example 8 The results of kinematic viscosity, viscosity index, low temperature fluidity test and heat resistance test of the mixed oil 3 obtained in Production Example 8 are shown in Table 1.

Comparative Example 1 Neopentyl glycol di (n) obtained in Production Comparative Example 1
Table 1 shows the results of kinematic viscosity, viscosity index, low temperature fluidity test, and heat resistance test of octyl).

Comparative Example 2 Neopentyl glycol di (n obtained in Production Comparative Example 2
Table 1 shows the results of kinematic viscosity, viscosity index, low temperature fluidity test and heat resistance test of -heptyl).

Comparative Example 3 Neopentyl glycol di (n obtained in Production Comparative Example 2
Table 1 shows the results of kinematic viscosity, viscosity index, low temperature fluidity test, and heat resistance test of -nonyl).

Example 9 3-Methyl-1,5-pentanedioldi (n-octyl) obtained in Production Example 1 was treated at 100 ° C. and 13.3 MPa.
The dehydration treatment was carried out for 5 hours under the conditions described above to obtain an ester having a water content of 12 ppm. Table 2 shows the results of the refrigerant compatibility test, electric insulation test, and hydrolysis stability test of this ester.

[0150]

Example 10 The 3-methyl-1,5-pentanedioldi (n-heptyl) obtained in Production Example 2 was treated at 100 ° C. and 13.3 MPa.
The dehydration treatment was carried out for 5 hours under the conditions described above to obtain an ester having a water content of 20 ppm. Table 2 shows the results of the refrigerant compatibility test, electric insulation test, and hydrolysis stability test of this ester.

Example 11 The ester (A) of 3-methyl-1,5-pentanediol and n-heptanoic acid and n-octanoic acid obtained in Production Example 3 was dehydrated to obtain an ester having a water content of 16 ppm. It was Table 2 shows the results of the refrigerant compatibility test, electric insulation test, and hydrolysis stability test of this ester.

Example 12 The ester (B) of 3-methyl-1,5-pentanediol obtained in Preparation Example 4 with n-heptanoic acid and n-octanoic acid was treated at 100 ° C. and 13.3 MPa. After dehydration treatment for 5 hours, an ester having a water content of 10 ppm was obtained. Table 2 shows the results of the refrigerant compatibility test, electric insulation test, and hydrolysis stability test of this ester.

Example 13 The ester of 3-methyl-1,5-pentanediol and n-heptanoic acid and n-nonanoic acid obtained in Production Example 5 was dehydrated for 5 hours at 100 ° C. and 13.3 MPa. This was treated to obtain an ester having a water content of 11 ppm. Table 2 shows the results of the refrigerant compatibility test, electric insulation test, and hydrolysis stability test of this ester.

Examples 14 to 18 The esters obtained in Production Examples 1 to 5 were tested for biodegradability. The results are shown in Table 3.

[0156]

As is clear from Table 1, the lubricating oil of the present invention has a well-balanced low viscosity at 0 ° C. and 40 ° C., and has a high viscosity index, so that it has low viscosity characteristics in a wide temperature range. Also, it has a small amount of volatilization and excellent heat resistance, -40 ° C.
It can be seen that it has the following pour point and is also excellent in low temperature fluidity. On the other hand, a lubricating oil using a diester obtained from a dihydric alcohol having a quaternary carbon such as neopentyl glycol has higher low temperature viscosity and volatilization amount than the lubricating oils of Examples even when the molecular weight is the same. growing. On the other hand, when the low temperature viscosity is low, the volatility resistance becomes poor, and conversely, when an ester having a high molecular weight is used to improve the volatility resistance, the low temperature viscosity becomes extremely high, which is an energy saving viewpoint. Is inferior.

Further, the lubricating oil of the present invention exhibits excellent performance as a refrigerating machine oil as shown in Table 2, and further has good biodegradability as shown in Table 3.

[0159]

The lubricating oil of the present invention has excellent heat resistance and
Energy saving due to low viscosity over a wide temperature range,
A lubricating oil with excellent fuel economy. Therefore, in addition to various lubricating oils such as gasoline engine oil, diesel engine oil, gas engine oil, gear oil, automatic transmission oil, bearing lubricating oil, lubricating oil for refrigerator, jet engine oil, hydraulic oil, compressor It can be applied to oil, gas turbine oil, grease base oil, and various lubricating oils that require biodegradability.

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[Procedure amendment]

[Submission date] August 20, 2002 (2002.8.2)
0)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

Specific examples of preferred diesters include 2
-Methyl-1,3-propanediol and carbon number 7-10
Examples of diesters of aliphatic saturated linear monocarboxylic acids include 2-methyl-1,3-propanediol di (n-
Heptanoate ), 2-methyl-1,3-propanediol di (n- octanoate ), 2-methyl- 1,3-
Examples include propanediol di (n- nonanoate ) and 2-methyl-1,3-propanediol di (n- decanoate ).

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0027

[Correction method] Change

[Correction content]

1,3-Butanediol and C7-10
Examples of diesters of aliphatic saturated linear monocarboxylic acids include 1,3-butanediol di (n- heptanoe
G), 1,3-butanediol di (n- Okutanoe
G), 1,3-butanediol di (n- Nonanoe
G ), 1,3-butanediol di (n- decanoate )
Is exemplified.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0028

[Correction method] Change

[Correction content]

The diester of 2-methyl-1,4-butanediol and an aliphatic saturated linear monocarboxylic acid having 7 to 10 carbon atoms is 2-methyl-1,4-butanediol di (n- heptanoate). ), 2-methyl-1,4-butanediol di (n- octanoate ), 2-methyl-
1,4-butanediol di (n- nonanoate ), 2-
Methyl-1,4-butanediol di (n- decanoe
G ) is illustrated.

[Procedure amendment 4]

[Document name to be amended] Statement

[Name of item to be corrected] 0029

[Correction method] Change

[Correction content]

1,4-Pentanediol and carbon number 7 to 1
Examples of diesters of aliphatic saturated linear monocarboxylic acid of 0 include 1,4-pentanediol di (n- heptanoe)
Over g), 1,4-pentanediol di (n- Okutanoe
Over g), 1,4-pentanediol di (n- Nonanoe
G), 1,4-pentanediol di (n- Dekanoe
G ) is illustrated.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Name of item to be corrected] 0030

[Correction method] Change

[Correction content]

As a diester of 2-methyl-1,5-pentanediol and an aliphatic saturated linear monocarboxylic acid having 7 to 10 carbon atoms, 2-methyl-1,5-pentanediol di (n- heptanoate) can be used. ), 2-methyl-1,5
-Pentanediol di (n- octanoate ), 2-methyl-1,5-pentanediol di (n- nonanoe)
G ), 2-methyl-1,5-pentanediol di (n-
Decanoate ) is exemplified.

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0031

[Correction method] Change

[Correction content]

Examples of diesters of 3-methyl-1,5-pentanediol and aliphatic saturated linear monocarboxylic acids having 7 to 10 carbon atoms include 3-methyl-1,5-pentanediol di (n- heptanoate). ), 3-methyl-1,5
-Pentanediol di (n- octanoate ), 3-methyl-1,5-pentanediol di (n- nonanoe)
G ), 3-methyl-1,5-pentanediol di (n-
Decanoate ) is exemplified.

[Procedure Amendment 7]

[Document name to be amended] Statement

[Name of item to be corrected] 0032

[Correction method] Change

[Correction content]

1,5-hexanediol and carbon number 7 to 1
Examples of the diester of 0 with an aliphatic saturated linear monocarboxylic acid include 1,5-hexanediol di (n- heptanoe).
Over g), 1,5-hexanediol di (n- Okutanoe
Over g), 1,5-hexanediol di (n- Nonanoe
G), 1,5-hexanediol di (n- Dekanoe
G ) is illustrated.

[Procedure Amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0033

[Correction method] Change

[Correction content]

Among the above-mentioned preferred diesters, 3-methyl-1,5-pentanediol di (n- heptanoate ) and 3-methyl-1,5-pentanediol di (n- octanoate ) are excellent in heat resistance. , 3-methyl-1,5-pentanediol di (n- nonanoate ),
3-methyl-1,5-pentanediol di (n- decano
Aate ) is preferable, and further, it is excellent in low temperature fluidity,
In particular, 3-methyl-1,5-pentanediol di (n-
Heptanoate ) and 3-methyl-1,5-pentanediol di (n- octanoate ) are preferred.

[Procedure Amendment 9]

[Document name to be amended] Statement

[Name of item to be corrected] 0126

[Correction method] Change

[Correction content]

Production Example 1 445.0 g of n-octanoic acid was placed in a one-liter four-necked flask equipped with a stirrer, a thermometer, and a water fractionation receiver with a cooling tube.
(3.09 mol), 177 g (1.5 mol) of 3-methyl-1,5-pentanediol, xylene (5% by weight relative to the total amount of acid and alcohol) and tin oxide (as a total amount of acid and alcohol) as a catalyst. 0.2% by weight) was charged, and the temperature was raised to 220 ° C. under reduced pressure. The esterification reaction was carried out for about 4 hours while removing the water produced with a theoretically possible amount of water (54 g) with a moisture fractionation receiver. After completion of the reaction, excess acid was removed by distillation. Then
After completion of the reaction, the solution was neutralized with an aqueous solution of caustic soda in excess of the total acid value, and then washed with water until it became neutral. Then, activated carbon treatment was carried out and further filtration was carried out to obtain 505 g of 3-methyl-1,5-pentanediol di (n- octanoate ). The total acid value of the obtained ester was 0.01 mgKOH / g.

[Procedure Amendment 10]

[Document name to be amended] Statement

[Name of item to be corrected] 0127

[Correction method] Change

[Correction content]

Production Example 2 401.7 g of n-heptanoic acid instead of n-octanoic acid
By the same method as in Production Example 1 except that (3.09 mol) was used, 496 g of 3-methyl-1,5-pentanediol di (n- heptanoate ) was obtained. The total acid value of the obtained ester was 0.01 mgKOH / g.

[Procedure Amendment 11]

[Document name to be amended] Statement

[Name of item to be corrected] 0131

[Correction method] Change

[Correction content]

Production Comparative Example 1 Neopentyl glycol di () was prepared in the same manner as in Production Example 1 except that 156 g (1.5 mol) of neopentyl glycol was used instead of 3-methyl-1,5-pentanediol. 500 g of n- octanoate ) was obtained. The total acid value of the obtained ester was 0.01 mgKOH / g.

[Procedure Amendment 12]

[Document name to be amended] Statement

[Correction target item name] 0132

[Correction method] Change

[Correction content]

Preparation Comparative Example 2 401.7 g of n-heptanoic acid instead of n-octanoic acid
(3.09 mol), instead of 3-methyl-1,5-pentanediol, neopentyl glycol 156 g
Neopentyl glycol di (n- heptanoe ) was prepared in the same manner as in Production Example 1 except that (1.5 mol) was used.
It was obtained over door) 463g. The total acid value of the obtained ester was 0.01 mgKOH / g.

[Procedure Amendment 13]

[Document name to be amended] Statement

[Name of item to be corrected] 0133

[Correction method] Change

[Correction content]

Preparation Comparative Example 3 488.2 g of n-nonanoic acid instead of n-octanoic acid
(3.09 mol), instead of 3-methyl-1,5-pentanediol, neopentyl glycol 156 g
Neopentyl glycol di (n- nonanoe ) was produced in the same manner as in Production Example 1 except that (1.5 mol) was used.
To obtain the door) 611g. The total acid value of the obtained ester was 0.
It was 01 mg KOH / g.

[Procedure Amendment 14]

[Document name to be amended] Statement

[Correction target item name] 0134

[Correction method] Change

[Correction content]

Production Example 6 3-Methyl-1,5-pentanediol di (n- octanoate ) obtained in Production Example 1 and sebacic acid di (2-
Ethylhexyl) (Sanso Sizer DO manufactured by Shin Nippon Rika
S ”) was mixed at 80:20 (weight ratio) to obtain a mixed oil 1. The total acid value of the mixed oil 1 was 0.01 mgKOH / g.

[Procedure Amendment 15]

[Document name to be amended] Statement

[Name of item to be corrected] 0135

[Correction method] Change

[Correction content]

Production Example 7 3-Methyl-1,5-pentanediol di (n- octanoate ) obtained in Production Example 1 and neopentyl glycol mixed fatty acid ester (n-octanoic acid: n-decanoic acid = 60: 40) ) Was mixed at 60:40 (weight ratio) to obtain a mixed oil 2. The total acid value of the mixed oil 2 was 0.01 mgKOH / g.

[Procedure Amendment 16]

[Document name to be amended] Statement

[Name of item to be corrected] 0136

[Correction method] Change

[Correction content]

Production Example 8 The 3-methyl-1,5-pentanediol di (n- heptanoate ) obtained in Production Example 2 and 2-ethylhexyl n-tetradecanoate were mixed at 70:30 (weight ratio),
Mixed oil 3 was obtained. The total acid value of mixed oil 3 is 0.01 mgKOH / g
Met.

[Procedure Amendment 17]

[Document name to be amended] Statement

[Name of item to be corrected] 0137

[Correction method] Change

[Correction content]

Example 1 Table 1 shows the results of kinematic viscosity, viscosity index, low temperature fluidity test and heat resistance test of 3-methyl-1,5-pentanedioldi (n- octanoate ) obtained in Production Example 1. Shown in.

[Procedure 18]

[Document name to be amended] Statement

[Name of item to be corrected] 0138

[Correction method] Change

[Correction content]

[0138]

[Procedure Amendment 19]

[Document name to be amended] Statement

[Correction target item name] 0139

[Correction method] Change

[Correction content]

Example 2 The results of kinematic viscosity, viscosity index, low temperature fluidity test and heat resistance test of 3-methyl-1,5-pentanedioldi (n- heptanoate ) obtained in Production Example 2 are shown in Table 1. Shown in.

[Procedure amendment 20]

[Document name to be amended] Statement

[Name of item to be corrected] 0146

[Correction method] Change

[Correction content]

Comparative Example 1 Neopentyl glycol di (n) obtained in Production Comparative Example 1
Table 1 shows the results of kinematic viscosity, viscosity index, low temperature fluidity test and heat resistance test of octanoate ).

[Procedure correction 21]

[Document name to be amended] Statement

[Correction target item name] 0147

[Correction method] Change

[Correction content]

Comparative Example 2 Neopentyl glycol di (n obtained in Production Comparative Example 2
Table 1 shows the results of kinematic viscosity, viscosity index, low temperature fluidity test, and heat resistance test of -heptanoate ).

[Procedure correction 22]

[Document name to be amended] Statement

[Name of item to be corrected] 0148

[Correction method] Change

[Correction content]

Comparative Example 3 Neopentyl glycol di (n obtained in Production Comparative Example 2
Table 1 shows the results of kinematic viscosity, viscosity index, low temperature fluidity test, and heat resistance test of nonanoate ).

[Procedure amendment 23]

[Document name to be amended] Statement

[Name of item to be corrected] 0149

[Correction method] Change

[Correction content]

Example 9 The 3-methyl-1,5-pentanediol di (n- octanoate ) obtained in Preparation Example 1 was treated at 100 ° C. and 13.3%.
It dehydrated for 5 hours under the condition of MPa to obtain an ester having a water content of 12 ppm. Table 2 shows the results of the refrigerant compatibility test, electric insulation test, and hydrolysis stability test of this ester.

[Procedure correction 24]

[Document name to be amended] Statement

[Correction target item name] 0150

[Correction method] Change

[Correction content]

[0150]

[Procedure correction 25]

[Document name to be amended] Statement

[Correction target item name] 0151

[Correction method] Change

[Correction content]

Example 10 The 3-methyl-1,5-pentanediol di (n- heptanoate ) obtained in Production Example 2 was treated at 100 ° C. and 13.3%.
Dehydration treatment was carried out for 5 hours under the condition of MPa to obtain an ester having a water content of 20 ppm. Table 2 shows the results of the refrigerant compatibility test, electric insulation test, and hydrolysis stability test of this ester.

[Procedure Amendment 26]

[Document name to be amended] Statement

[Name of item to be corrected] 0156

[Correction method] Change

[Correction content]

[0156]

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) C10N 40:04 C10N 40:04 40:08 40:08 40:12 40:12 40:13 40:13 40:25 40 : 25 40:30 40:30 50:10 50:10 (72) Inventor Hirotaka Tomizawa 13 Fukumi-ku, Kyoto City Fukumi-ku, Yashima-cho, Shinjima Rika Co., Ltd. F-term (reference) 4H104 BB34 LA01 LA04 LA20 PA01 PA02 PA03 PA05 PA07 PA08 PA20 PA41 QA18

Claims (5)

[Claims] 1. A lubricating oil containing a diester represented by the general formula (1). [In the formula, R ¹ and R ² are the same or different and have 3 to 3 carbon atoms.
17 represents a linear alkyl group. A represents a residue of an aliphatic dihydric alcohol having 2 to 10 carbon atoms or having 1 or 2 branched chains. However, when A has two branched chains, the two branched chains are not bound to the same carbon atom. ] 2. The lubricating oil according to claim 1, wherein A in the general formula (1) is a residue of an aliphatic dihydric alcohol having one or two branched chains. 3. The lubricating oil according to claim 1, which is used as engine oil, gear oil, automatic transmission oil, and / or shock absorber oil. 4. The lubricating oil according to claim 1, which is used as a lubricating oil for bearings. 5. The lubricating oil according to claim 1, which is used as a lubricating oil for a refrigerator.