JPH09176668A - Lubricating oil composition - Google Patents

Abstract

(57) Abstract: An object of the present invention is to provide a lubricating oil composition which uses a synthetic oil or a synthetic oil and a mineral oil as a lubricating base oil and has an excellent friction adjusting ability. A lubricating oil composition of the present invention is a synthetic oil or
Lubricating base oils composed of synthetic oils and mineral oils have the following general formula (1) (In the formula, a is an integer of 1 to 8 and c is an integer of 0 to 8; when a is 1 to 6, b = 0 or 1; and when a is 7 and 8, b =
1 and n represents 1 to 10) (poly)
It is characterized by containing glycerin ether.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel lubricating oil composition, and more particularly, it has a certain substituent (poly).
The present invention relates to a novel lubricating oil composition containing glycerin ether.

[0002]

2. Description of the Related Art Recent lubrication devices are required to be more compact, have higher performance, and be maintenance-free. or,
Recently, with the promotion of energy saving, reducing energy loss and increasing mechanical efficiency has become one of the important issues.

Lubricating oils are subject to physical shear, high temperatures, and
Since it is exposed to high pressure and an oxidizing atmosphere, it deteriorates over time. For example, some extreme pressure agents may only show extreme pressure performance, and most of the rest may be oxidatively deteriorated under the above conditions and decompose before exhibiting extreme pressure performance to become sludge. . In particular, in the internal combustion engine NO _X, SO _X, Haidoroka - blow such Bonn - also contamination Baigasu has become a deteriorated condition severe.

In recent years, attempts have been made to improve the temperature-viscosity characteristics of the lubricating base oil itself in order to improve the problems of wear at high temperatures, seizure, and energy loss at low temperatures. In other words, as a lubricating base oil, measures such as using one synthesized by chemical means have been taken, but for this reason, the antioxidant ability of the sulfur compounds, nitrogen compounds, etc., which are the impurities contained in the mineral oil, has been improved. Since the components contained therein have been eliminated, there is a problem in that the thermal stability of the lubricating base oil alone decreases. An even bigger problem is the high V
Since I oil contains a large amount of paraffin, the solubility of the lubricating oil additive tends to be poor.

By the way, it has been conventionally known that glycerin ethers are effective as friction modifiers. For example, in JP-A-59-25890, zinc dithiophosphate (ZDTP) and batyl alcohol are added to a mineral oil base oil,
It is described that glycerin ether such as chimyl alcohol and cerakil alcohol is added to have excellent friction adjusting ability.

[0006]

However, synthetic oils such as poly-α-olefins, which are currently used as lubricating base oils, have poor solubility of additives, and in glycerin ethers, alkyl groups having a long carbon chain, Those having an alkenyl group were particularly difficult to dissolve uniformly.

Accordingly, it is an object of the present invention to provide a lubricating oil composition which uses a synthetic oil or a synthetic oil and a mineral oil as a lubricating base oil and has an excellent friction adjusting ability.

[0008]

Therefore, the inventors of the present invention have made extensive studies and found that when a synthetic oil or a semi-synthetic oil obtained by mixing a synthetic oil and a mineral oil is used as a lubricating base oil, it has a certain carbon chain. It was discovered that only (poly) glycerin ether exerts an excellent friction adjusting ability, and the present invention has been completed.

That is, the present invention provides a synthetic base oil or a lubricating base oil composed of a synthetic oil and a mineral oil with the following general formula (1):

Embedded image (In the formula, a is an integer of 1 to 8 and c is an integer of 0 to 8; when a is 1 to 6, b = 0 or 1; and when a is 7 and 8, b =
1 and n represents 1 to 10) (poly)
A lubricating oil composition comprising glycerin ether.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In the lubricating oil composition of the present invention,
What can be used as the lubricating base oil is a synthetic oil or a semi-synthetic oil composed of a synthetic oil and a mineral oil.

Here, the synthetic oil is a chemically synthesized lubricating base oil, and includes poly-α-olefin, polyisobutylene (polybutene), diester, polyol ester, phosphate ester, silicate ester, Examples include polyalkylene glycols, polyphenyl ethers, silicones, fluorinated compounds and alkylbenzenes. Of the above synthetic oils, poly-α obtained by polymerizing α-olefin
-Olefins can be preferably used. The α-olefin includes, for example, propylene, butylene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1
-Nonene, 1-decene, 1-undecene, 1-dodecene, 1-tetradecene, 1-hexadecene and the like. Poly-α-olefins are produced by oligomerizing these α-olefins and appropriately hydrogenating them.
In the oligomerization, a Lewis acid, a Ziegler catalyst, a Ziegler-Natta catalyst or the like is allowed to act on the product. Among these, those having a molecular weight of 300 to 2500 synthesized from an α-olefin having 4 to 16 carbon atoms have an appropriate pour point and are preferable. Since the poly-α-olefin has a constant molecular structure, it has excellent lubricity as compared with untreated mineral oil and the like, and the effect of the additive is particularly good.

Polyol ester is also preferably used. Polyol ester means polyhydric alcohol and 1
It is an ester produced from a monovalent or polyvalent carboxylic acid by ordinary experimental and industrial production methods.

Among polyhydric alcohols, hindered alcohols (alcohols in which the β-position of the hydroxyl group is quaternary carbon)
Is particularly preferred. Examples thereof include neopentyl glycol, trimethylolethane, trimethylolpropane, pentaerythritol, dipentaerythritol, tripentaerythritol, and alkylene oxide adducts thereof.

Further, among the monovalent or polyvalent carboxylic acids, compounds having 4 to 16 carbon atoms are preferable. For example, butyric acid, isobutyric acid, valeric acid, isovaleric acid, pivalic acid, capric acid, caproic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, oxalic acid, malonic acid, succinic acid,
Glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, methacrylic acid, crotonic acid,
Isocrotonic acid, oleic acid, fumaric acid, maleic acid,
Examples thereof include benzoic acid, toluic acid, phthalic acid and naphthoic acid. Among them, butyric acid, isobutyric acid, valeric acid, isovaleric acid, pivalic acid, capric acid, caproic acid, caprylic acid,
Lauric acid, myristic acid and palmitic acid are preferred.
Among these, polyol ester having a molecular weight of 200 to 1200 is particularly preferable.

Further, diesters are also preferably used. The diester has two ester bonds in one molecule, and is an ester produced from a monohydric alcohol and a dibasic acid by a usual experimental or industrial production method.

The monohydric alcohol may be linear or branched. The dibasic acid preferably has 6 to 12 carbon atoms, and examples thereof include adipic acid, azelaic acid, sebacic acid and dodecanedioic acid. Among these, molecular weight 2
Diesters of 00 to 700 are preferred.

These synthetic oils can be used alone or in combination of two or more as a lubricating base oil.

A so-called semi-synthetic oil obtained by mixing these synthetic oils and mineral oils can also be used as the lubricating base oil.
Here, the mineral oil refers to one that is separated, distilled, and refined from natural crude oil, and examples thereof include paraffin-based and naphthene-based oils, and those obtained by hydrogenating and solvent refining these.

Of the impurities contained in mineral oil, aromatic components and sulfur components reduce the effect of glycerin ether, which is an additive, and other components, so that aromatic hydrocarbons in mineral oil are hydrotreated. 1% or less of ingredients and 100 of sulfur
Those treated to ppm or less are particularly preferable.

The viscosity of the lubricating base oil used in the present invention is not particularly limited, but preferably 2 to 5 at 100 ° C.
It is 0 cSt, more preferably 2 to 30 cSt. If the viscosity is too low, the oil film formation during lubrication may be insufficient, which may cause wear or seizure. If it is too large, viscous resistance tends to increase power loss.

In the (poly) glycerin ether represented by the general formula (1) which is an essential component of the present invention, a is 1 to
8, c is an integer of 0-8, and when a is 1-6, b
= 0 or 1, when a is 7, 8 represents b = 1, and n represents 1-10. Further, a and c may be different, but are preferably the same. This is because the unsaturated bond has better solubility in the center of the substituent. or,
When a and c are small, it tends to be slightly difficult to dissolve, so 6 to 8 is particularly preferable for a and c. Further, when n becomes large, industrial production becomes difficult. Therefore, n is particularly preferably 1 to 3.

Here, examples of the substituent satisfying the above conditions are methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, nonyl, decyl, undecyl, dodecyl, allyl,
Examples include isopropenyl, butenyl, isobutenyl, pentenyl, isopentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tetradecenyl, oleyl and the like. Among these, oleyl group and lauryl group are soluble and lubricious. And is particularly preferable.

Substituents which do not satisfy the above conditions, for example, stearyl group (a = c = 9, b = 0), palmityl group (a =
(Poly) glycerin ether having (c = 8, b = 0), etc. cannot exhibit effective friction adjusting ability. This is because synthetic oil or semi-synthetic oil, which is a lubricating base oil, has a low ability to dissolve a lubricating oil additive, which is a problem that cannot occur when only mineral oil is used as a lubricating base oil. . The substituent satisfying the above conditions has a relatively short chain, is sufficiently dissolved in synthetic oil or semi-synthetic oil, and has a high friction adjusting ability.
Therefore, when a synthetic oil or a semi-synthetic oil is used as the lubricating base oil, only the (poly) glycerin ether having a substituent satisfying the above conditions exerts an excellent friction adjusting ability.

The addition amount of the (poly) glycerin ether is not particularly limited, but if it is too small, a sufficient friction adjusting effect cannot be obtained, and if it is too large, there is no effect to match the addition amount and it is meaningless. The base oil is preferably 0.05 to 15% by weight, more preferably 0.1 to 10% by weight.
%, Most preferably 0.3 to 5.0% by weight.

Within the scope of the object of the present invention, various known additives as required, for example, friction modifiers such as higher fatty acids, higher alcohols, amines, esters, half esters, sulfur-based, chlorine-based, phosphorus System, organometallic system, particularly sulfurized oxymolybdenum organodithiocarbamate, sulfurized oxymolybdenum organodithiophosphate, sulfurized oxymolybdenum organoxanthate, amine molybdate, zinc organodithiophosphate, extreme pressure agent such as zinc organodithiocarbamate, phenols , Especially hindered phenols, amines, especially phenylamine,
Antioxidant such as naphthylamine, neutral or highly basic alkali or alkaline earth metal sulfonate, phenene
Detergents such as carboxylic acid, carboxylate, dispersants such as (borated) succinimide, benzylamine, high molecular weight poly
(Meth) acrylate, polyisobutylene, polystyrene, ethylene-propylene copolymer, styrene-isobutylene copolymer and other viscosity index improvers, or esters, silicones and other defoamers, other rust inhibitors, pour point A depressant and the like can be added within the usual range of use.

The lubricating oil composition of the present invention comprises a vehicle engine including automobiles, a two-cycle engine, an aircraft engine, a marine engine and a locomotive engine (these engines may be gasoline, diesel, gas or turbine). ) And the like for internal combustion engines, automatic transmission liquids, transaxle lubricants, gear lubricants, metalworking lubricants, etc.

[0027]

The present invention will be described in detail below with reference to examples. The lubricating base oil, (poly) glycerin ether, etc. used in the test are as follows: Base oil 1: Poly-α-olefin obtained by the oligomerization of 1-decene (viscosity at 100 ° C. is 5. 5 cS
t, VI = 132, molecular weight 770) 20%, mineral oil high VI oil obtained by hydrocracking process of mineral oil obtained from crude oil (viscosity 4.1 cSt at 100 ° C., VI =
126) 80% synthetic oil-mineral oil. The aromatic component was 1% or less and the sulfur content was 100 ppm or less. Poly-α-olefin obtained by oligomerization of base oil 2: 1-decene (viscosity 5.5c at 100 ° C.
St, VI = 132, molecular weight 770 80%, polyol ester (viscosity 4.0 cSt at 100 ° C., VI = 1
33, molecular weight 512) 20% synthetic oil. Base oil 3: synthetic oil based on diester (viscosity is 100
5.3 cSt at C, VI = 138, molecular weight 510). Base oil 4: 60% by weight of the poly-α-olefin used in base oil 2. A synthetic oil-based oil comprising 40% by weight of a polyol ester.

(Poly) glycerin ether 1: glycerin monooleyl ether [in the general formula (1), a = c =
8, b = 1, n = 1) (poly) glycerin ether 2: glycerin monolauryl ether (a = c = 6, b = 0, n = 1) (poly) glycerin ether 3: glycerin monopalmityl ether (a = C = 8, b = 0, n = 1) (poly) glycerin ether 4: glycerin monostearyl ether (a = c = 9, b = 0, n = 1) (poly) glycerin ether 5: diglycerin monooleyl Ether (a = c = 8, b = 1, n = 2) (poly) glycerin ether 6: triglycerin monooleyl ether (a = c = 8, b = 1, n = 3)

A sample was prepared using the above base oil and (poly) glycerin ether, and the obtained sample was subjected to a solubility test and a friction coefficient measurement test. <Solubility test> 1 of lubricating base oils 1 to 4 heated to 80 ° C
After dissolving the required amount of (poly) glycerin ether 1 to 6 in 100 parts by weight, the mixture was allowed to stand at room temperature and tested for solubility.
In the table, ◯ means no precipitation in 30 days, and x means precipitation within 3 days.

<Friction Coefficient Measurement Test> The friction coefficient is SRV.
It carried out on the following conditions using the measurement tester. <Conditions> Point contact: The test conditions were ball-on-plate point contact conditions. That is, the upper ball (φ10 mm) is placed on the plate (φ
24 × 7.85 mm) and reciprocally oscillate for 15
The friction coefficient was measured after a minute. Both materials are SUJ-
It was 2. Load: 120 N Temperature: 80 ° C. Measurement time: 15 minutes Amplitude: 1 mm Cycle: 50 Hz The blending of the test oil and the measurement results are shown in the table below. In addition, among the numerical values in the table, the lubricant base oil is sample No., and the (poly) glycerin ether is% by weight relative to the lubricant base oil.

[0031]

[Table 1]

[0032]

[Table 2]

[0033]

[Table 3]

[0034]

The effect of the present invention is to provide a novel lubricating oil composition containing a synthetic oil or a semi-synthetic oil consisting of a synthetic oil and a mineral oil and containing (poly) glycerin ether having a specific substituent. is there.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication C10M 169/04 C10M 169/04 // C10N 30:06 40:04 40:20 40:25 (72 ) Inventor Kazutoshi Morita 7-35 Higashiokyu, Arakawa-ku, Tokyo Asahi Denka Kogyo Co., Ltd. (72) Inventor Yoko Saito 7-35 Higashiohisa, Arakawa-ku, Tokyo Asahi Denka Kogyo Co., Ltd.

Claims (3)

[Claims] 1. A synthetic oil or a lubricating base oil composed of a synthetic oil and a mineral oil is added to the following general formula (1): (In the formula, a is an integer of 1 to 8 and c is an integer of 0 to 8; when a is 1 to 6, b = 0 or 1; and when a is 7 and 8, b =
1 and n represents 1 to 10) (poly)
A lubricating oil composition comprising glycerin ether. 2. The synthetic oil is a poly-α-olefin and / or
The lubricating oil composition according to claim 1, which comprises a diester and / or a polyol ester. 3. The lubricating oil composition according to claim 1, wherein the amount of the (poly) glycerin ether added is 0.05 to 15% by weight based on 100 parts by weight of the lubricating base oil.