JPH10316983A - Lubricating composition - Google Patents

Abstract

(57) [Summary] [Problem] Engine performance (lubricity, initial torque, cleanliness,
Provided is a lubricating composition suitable as a two-cycle oil or the like which is excellent in both smoke and exhaust system obstruction and biodegradability. A JAS containing an ester compound of the formula 1
A lubricating composition that meets OFC or ISOEGD standards and has biodegradability (67% or more according to the CEC-L33-T-82 method). [Wherein R ¹ , R ² = H, alkyl (eg, methyl, ethyl, propyl), alkenyl (eg, vinyl), R ³ , R
⁴ = alkyl (eg, heptyl, heptadecyl, behenyl), alkenyl (eg, octadecenyl), m, n = 0
~ 50]

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a lubricating composition,
More specifically, it is excellent as a two-cycle engine oil having excellent engine performance such as lubricity, initial torque, cleanliness, smoke, exhaust system obstruction, low temperature startability, anti-seizure property, and excellent biodegradability. A lubricating composition.

[0002]

2. Description of the Related Art Generally, a two-cycle engine has a simple structure and is widely used in small motorcycles, outboard motors, generators, chain saws, and other general-purpose engines. However, due to the mechanism of the two-stroke engine, unburned engine oil is discharged together with the exhaust gas, which may pollute the environment. That is, small motorcycles and chainsaws that emit exhaust gas into the air pollute the land, outboard motors that emit exhaust gas into the water pollute rivers, lakes, the sea, etc. In the case of a generator or a general-purpose engine, there is a high possibility that the two-stroke engine oil will adversely affect the environment in which the two-stroke engine oil is used.

[0003] In recent years, where the importance of environmental protection has been pointed out, the demand for lubricating oil such as two-stroke engine oil cannot only be improved in engine performance, but the effect on the environment cannot be neglected. From such a viewpoint, an ester of hindered alcohol and a linear saturated fatty acid having 8 to 12 carbon atoms and a hindered alcohol, a linear saturated fatty acid having 8 to 12 carbon atoms and a dibasic acid having 2 to 50 carbon atoms have been used. Lubricating oil composition containing an ester of
No. 8276) and a two-cycle engine lubricating oil comprising a carbonate ester and a polyol ester and / or a complex ester (Japanese Patent Application Laid-Open No. 7-173377).

[0004] Although these conventional engine oils have some degree of biodegradability and some improvement in engine performance, some of them are still insufficient in biodegradability, and the overall engine performance is low. No improvement is considered. That is, in the case of the lubricating oil composition disclosed in JP-A-5-98276, no consideration is given to engine performance other than high-temperature detergency, lubricity and anti-seizure properties. The disclosed one merely improves the smoke performance, lubricity, and anti-seizure performance of the engine. Oil having excellent engine performance needs to be excellent in all of lubricity, initial torque, cleanliness, smoke, exhaust system obstruction, and the like. JASO (Automobile Corporation) Technical Society) M345-
93, and the type of performance and the reference index are determined as shown in Table 1 below. Among these, the FC standard (hereinafter referred to as the JASO FC standard) is the highest-performance oil standard. In order to satisfy the JASO FC standard, all of the lubricity index, the initial torque index, the cleanliness index, the exhaust smoke index, and the exhaust system obstruction index need to show a certain value or more.

[Table 1]

[0005] As a standard similar to the JASO FC standard, the ISO EGD standard is known. The conditions for satisfying the standard are shown in Table 2. In terms of the requirement that cleanliness is 125 or more, JASO
It is different from FC standard.

[Table 2]

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and has been applied to the overall engine performance such as lubricity, initial torque, cleanliness, smoke, and exhaust system obstruction. It is an object of the present invention to provide a lubricating composition which is excellent and has excellent biodegradability and which has not been proposed before.

[0007]

Means for Solving the Problems As a result of intensive studies, the present inventor has known that biodegradability is conventionally imparted, but the composition causes generation of smoke and deterioration of cleanliness. It has been found that when an ester having a specific chemical structure is also blended as an already known ester, a lubricating composition capable of solving the above-mentioned problems can be obtained, and further studies have been made to complete the present invention.

That is, the present invention provides the following formula 1: (Wherein, R ¹ and R ² independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or a carbon atom having 2 carbon atoms)
And R ³ and R ⁴ independently represent an alkyl group having 1 to 50 carbon atoms or an alkenyl group having 2 to 50 carbon atoms, and m and n each independently represent 0 to 10. And represents an integer of from 50 to 50).
The present invention relates to a lubricating composition satisfying the C standard and having biodegradability.

The present invention also provides the following formula 1: (Wherein, R ¹ and R ² independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or a carbon atom having 2 carbon atoms)
And R ³ and R ⁴ independently represent an alkyl group having 1 to 50 carbon atoms or an alkenyl group having 2 to 50 carbon atoms, and m and n each independently represent 0 to 10. To an integer of 50 to 50), and comprises an ISO EG
The present invention relates to a lubricating composition satisfying the D standard and having biodegradability.

R ¹ and R ² in the above formula 1 may be the same or different from each other, and may be a hydrogen atom or a linear or branched C ¹ -C 1 atom.
An alkyl group such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, nonyl or Decyl group or an isomer thereof, or straight or branched carbon atom 2
To 10 alkenyl groups such as vinyl, propenyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl or decenyl or isomers thereof.

R ³ and R ⁴ in the above formula 1 may be the same or different from each other, and may be a straight-chain or branched alkyl group having 1 to 50 carbon atoms or a straight-chain or branched carbon atom. 2 to 50 alkenyl groups. Specific examples include, in addition to those exemplified for R ¹ and R ² , an alkyl group or an alkenyl group corresponding to the number of carbon atoms, that is, an undecyl group or a pentacontyl group, or an undecenyl group or a pentaconenyl group. R ³ and R ⁴ are each independently preferably an alkyl group having 7 to 30 carbon atoms or an alkenyl group having 7 to 30 carbon atoms.

Further, m and n in the above formula 1 may be the same or different, and are integers of 0 to 50. In terms of ease of production, etc., the sum of m and n is 40 or less. Preferably, there is.

As the ester compound represented by the above formula (1), those having a total carbon number of 20 to 80 are preferable in view of usability, biodegradability and improvement of engine performance. Further, the ester compound represented by the above formula 1 is JIS K
The kinematic viscosity at 100 ° C. based on 2283 is preferably in the range of ² to 40 mm ² / s, particularly 4 to 20 mm ² / s, from the viewpoints of usability, biodegradability and engine performance improvement. It goes without saying that the above ester compounds may be used alone or in combination of two or more.

The ester compound represented by the above formula 1 used in the present invention is generally represented by the following formula 2: And a corresponding linear or branched saturated fatty acid or linear or branched unsaturated fatty acid represented by the following formula 3: R ³ COOH (3). obtain. In the above equations 2 and 3,
R ¹ , R ² , R ³ , m and n have the same meanings as defined for Formula 1, and as the fatty acid, it is needless to say that a plurality of compounds in which R ³ has different meanings may be used. is there. The fatty acid may be used in the form of a derivative such as an acid anhydride, an acid halide or a metal salt in addition to the free acid. Further, in addition to the above-mentioned reaction between an acid and an alcohol, a reaction between an alkyl halide and a silver salt of an acid, or an alkoxide acting on an acid chloride or an acid anhydride can also be used as a compound represented by the formula 1 in the present invention. Can be produced. As the ester compound preferably used in the present invention, neopentyl glycol (2,2-dimethyl-1,3-propanediol),
2,2-dipropyl-1,3-propanediol, 2,
2-dipentyl-1,3-propanediol, 3,3-
Diols such as dimethyl-1,5-pentanediol, 4,4-dimethyl-1,9-nonanediol, 8-methyl-8-ethyl-1,15-pentadecanediol or derivatives thereof, and saturated fatty acids such as acetic acid; Butyric acid, caproic acid, heptanoic acid, caprylic acid, nonanoic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, behenic acid, etc., unsaturated fatty acids such as acrylic acid, crotonic acid, undecylenic acid,
Those produced from oleic acid, erucic acid, linoleic acid, linolenic acid, arachidonic acid, etc., or isomers or derivatives thereof can be exemplified.

The lubricating composition of the present invention preferably contains 15 to 90% by weight, particularly 25 to 80% by weight of the ester compound represented by the above formula (1).

Other components of the lubricating composition of the present invention include, but are not particularly limited to, mineral oils, synthetic lubricating base oils, additives and the like, all of which are conventional. Mineral oils include paraffinic and naphthenic oils obtained by refining lubricating oil fractions obtained by distilling crude oils under normal pressure and reduced pressure. Among them, those having a flash point of 70 ° C or higher for viscosity adjustment are petroleum oils. Solvents, such as Stoddard solvent, mineral spirit, kerosene, normal paraffin, isoparaffin, and propylene oligomer. Synthetic lubricating base oils include poly-α-olefins (eg, 1-octene oligomer, 1-decene oligomer, etc.), polybutene, alkylbenzene, alkylnaphthalene, polyglycol, diester (eg, ditridecyl glutarate, di-2-ethylhexyl adipate) , Diisodecyl adipate, ditridecyl adipate, di-2-ethylhexyl sebacate, etc.);
(E.g., trimethylolpropane stearate, trimethylolpropane oleate, pentaerythritol 2-ethylhexanoate, carbonate, etc.), polyphenyl ether, fluorine-based oil, silicone oil, etc. . Examples of the additives include detergents and dispersants (eg, basic calcium sulfonate, basic calcium phenate, basic calcium salicylate, alkenyl succinimide, benzylamine, polyalkenylamine, or vinylpyrrolinone, vinylpyrrolidone) , Polyethylene glycol or copolymer of methacrylate and alkyl methacrylate, etc.), pour point depressant (eg, polymethacrylate, condensate of paraffin wax chloride and naphthalene, etc.), viscosity index improver (eg, polymethacrylate, ethylene-propylene copolymer, Polyolefin, polyisobutylene, polyalkylstyrene, etc.), antioxidants (for example, phenol derivatives, amine derivatives,
Organic sulfides or metal salts of dialkyldithiophosphoric acid, dialkyldithiocarbamic acid, etc.), corrosion inhibitors (eg, polysulfide, zinc dialkyldithiophosphate,
Benzotriazole, etc.), rust inhibitor (eg, sulfonate, carboxylate, carboxylic acid, etc.), defoamer (eg, dimethylpolysiloxane, diethylsilicate, etc.), extreme pressure agent / anti-wear agent (eg, sulfur) Compounds, phosphorus compounds, metal salts of dialkyldithiophosphoric acid, etc.), oil agents and friction modifiers (eg higher fatty acids, higher alcohols, or amines, esters, sulfurized fats, chlorinated fats and oils,
Organic compounds of molybdenum, etc.), solid lubricants (eg, molybdenum disulfide, graphite, etc.) and the like. The mixing ratio of these mineral oils, synthetic lubricating base oils, additives and the like is not particularly limited, and can be easily determined according to the intended lubricating composition.
% Of mineral oil, 0 to 50% by weight of mineral oil, 20 to 80% by weight of synthetic lubricating base oil and 3 to 30% by weight of additives.

The lubricating composition of the present invention contains the ester compound represented by the above formula (1), and is compliant with JASOFC standard or IS
It is characterized by meeting the OEGD standard and having biodegradability. The JASO FC standard is a measure of overall engine performance, and satisfying the standard means that the lubricity index (LIX) is 95 or more, the initial torque index (TIX) is 98 or more, and the cleanliness index (DIX). 95 or more, exhaust smoke index (SIX) 85 or more, and exhaust system obstruction index (B
IX) is required to be 90 or more. Also, IS
The OEGD standard has the same requirements for lubricity index (LIX), initial torque index (TIX), exhaust smoke index (SIX) and exhaust system blockage index (BIX) as for the JASOFC standard, and cleanliness index (GD DIX). ) Is 12
It is required to be 5 or more. In the present invention, the term “biodegradable” means that the lubricating composition is a CO ₂ by the action of microorganisms in nature.
Means that can be decomposed into and H ₂ O innocuous substances such as,
In general, results from tests using standard biodegradability test methods,
It means meeting the criteria. The following can be mentioned as standard biodegradability test methods (the values in parentheses are standard values to be regarded as biodegradable): Modified AFN
OR test method [OECD301A] (70% or more), modified Sturm test method [OECD301B] (60% or more), modified MITI test method [OECD301C] (60% or more)
%), Bottle test method with stopper [OECD301D] (60
% Or more), modified OECD screening test method [OEC
D301E] (70% or more), Zahn-Wellen
s test method [OECD302B] (20% or more), CEC
-L-33-T-82 method (67% or more), Chemical Substances Control Law [coulometer method] (35-40%). At present, the most widely used method is the CEC-L-33-T-82 method, which shows a biodegradability of 67% or more by this test as a condition for attaching the Eco Mark to products. Is required. For details of this test method, see Coordinating
European Council for Developement of Performance
Tests for Lubricants and Engine Fuels; Tentative T
est Method CEC-L-33-T-82, 1982 and Approved Test
See Method CEC-L-33-A-93, 1995. Recently, there has been a move from the CEC method as a biodegradability evaluation test to a modified Sturm method, which is a more stringent biodegradability test. Replacing this biodegradability test has a significant impact on the assessment of ester biodegradability. That is, other esters except the ester used in the present invention had a biodegradability of 90% or more by the CEC method, but 6% by the modified Sturm method.
It will be less than 0%. However, it has been confirmed that the ester used in the present invention exhibits a biodegradability of 80% or more by this modified Sturm method.

[0018]

DETAILED DESCRIPTION OF THE INVENTION As described above, although the present invention contributes to imparting biodegradability, it has been established that among ester compounds that are known to increase smoke and deteriorate cleanliness, By selecting one with a chemical structure of, it is possible to provide a lubricating composition that exhibits sufficient biodegradability and has excellent engine performance such as lubricity, initial torque, cleanliness, smoke, exhaust system obstruction, etc. It was done. For this reason, the lubricating composition of the present invention can be used for small motorcycles, outboard motors, generators, chain saws, and other general-purpose engines.
It is suitably used as a cycle engine oil. Further, the lubricating composition of the present invention is a four-stroke engine oil, a hydraulic oil,
It is also suitable as gear oil, metal working oil, rolling oil, refrigerating machine oil and the like.

[0019]

EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited to these examples. Example 1 An ester of neopentyl glycol and a fatty acid containing isostearic acid as a main component [hereinafter referred to as ester A, 100]
Kinematic viscosity at ℃ (based on JIS K2283) 8.0
mm ² / s], and the kinematic viscosity at 100 ° C. of the oil itself was adjusted to 8.5 mm ² / s to obtain a test oil. For this test oil, the lubricity index (LIX) and the initial torque index (TI) required by the JASO FC standard
X), cleanliness index (DIX), exhaust smoke index (SIX), and exhaust system obstruction index (BIX) are measured according to a predetermined test method, and CEC-L-33-T-82 is measured.
Biodegradability was measured according to the method. The test results are summarized in Table 3 below together with the composition of the test oil.

Comparative Examples 1 to 3 Oils containing a mixture of an ester of pentaerythritol and octanoic acid and an ester of pentaerythritol and decanoic acid (hereinafter referred to as ester B) instead of the ester in Example 1 Example 1) and oil (Comparative Example 2) using a mixture of an ester of trimethylolpropane and octanoic acid and an ester of trimethylolpropane and decanoic acid (hereinafter referred to as ester C). A similar test was performed. And as Comparative Example 3,
The same test as in Example 1 was performed on a commercially available two-stroke engine oil containing no ester. The results of these tests, together with the composition of each oil, are summarized in Table 3 below.

[0021]

[Table 3] (In the above table, nd means not tested.)

As described above, according to the JASO FC standard, the lubricity index is 95 or more, the initial torque index is 98 or more, the cleanliness index is 95 or more, the exhaust smoke index is 85 or more, and the exhaust system obstruction index is It is required to be 90 or more, and in order to attach the Eco Mark, CEC-L-33-T-
According to the 82 method, it is required to have a biodegradability of 67% or more. From the results shown in Table 1, while only the oil containing ester A of Example 1 according to the present invention satisfies both the JASO FC standard and the CEC biodegradability,
The oil of Comparative Example 1 has low biodegradability, the oil of Comparative Example 2 has poor engine performance at least in terms of exhaust smoke, and the commercial oil of Comparative Example 3 has good engine performance, but has very high biodegradability. It turns out that it is low.

Example 1 shows an example using an ester compound which is easily available and which is excellent in improving biodegradability and engine performance.
It is needless to say that a similar lubricating composition having both good biodegradability and good engine performance can be obtained when the ester compound represented by

Examples 2 to 6 Test oils having another composition using the ester of Example 1 (Example 2), and a fatty acid mainly composed of caprylic acid and neopentyl glycol in place of the ester of Example 1 With ester D (viscosity at 100 ° C. 2.1)
(Example 3), ester E of oleic acid-based fatty acid and neopentyl glycol (viscosity at 100 ° C. 6.0) (Examples 4, 5) or another fatty acid containing oleic acid as a main component The same evaluation as in Example 1 was carried out on a test oil having the composition shown in Table 4 using ester F (viscosity at 100 ° C. 7.7) of phenol and neopentyl glycol (Example 6). Was also evaluated by the test method required by the ISO EGD standard (GD method cleanliness index), and the biodegradability was also evaluated by the modified Sturm method. The results are also shown in Table 4.

[0025]

[Table 4] (In the above table, nd means not tested.)

Test Example A comparison was made between the test oils of Example 2 and Comparative Example 3 at low temperature startability. Evaluation of low temperature startability is based on Test Method JPI-5.
It carried out by measuring Brookfield viscosity according to S-26-85. The lower the viscosity, the better the low-temperature startability. Table 5 shows the results.

[Table 5]

[0027]

As described in detail above, the lubricating composition of the present invention, which contains a specific ester compound, has sufficient biodegradability and JASO to give the Eco Mark.
It has both the general engine performance such as FC standard and ISO EGD standard, has no fear of environmental pollution and shows excellent engine performance, and has never been proposed before. . Therefore, the lubricating composition of the present invention is suitable as a two-cycle engine oil, and can be used as a four-cycle engine oil, a working oil, a gear oil, a metal working oil, a rolling oil, a refrigerator oil, and the like. Although a lubricating composition containing an ester compound exhibits a certain degree of biodegradability, the index of exhaust smoke is poor and there is a problem in actual use. Further, a lubricating composition satisfying the JASO FC standard and the ISO EGD standard has a low biodegradability. Under the present circumstances where only degradability is not exhibited, the lubricating composition of the present invention is environmentally friendly in terms of excellent biodegradability and cleanliness, and has excellent engine performance in terms of lubricity and the like, It can be said that there is a great contribution to this field.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Akihiro Shibata, Inventor, 6-1, Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture General Research Institute, Inc. (72) Inventor Satoshi Fukushima 6, Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa No. 1 in General Research Laboratory of General Petroleum Co., Ltd. (72) Inventor Katsunori Okaba 6-1 Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture, Japan Central Research Laboratory of General Petroleum Co., Ltd. (72) Inventor Masao Baba Kawasaki, Kawasaki-shi, Kanagawa Prefecture 6-1 Ukishima-cho, Ward-ku General Research Institute, Inc. Central Research Laboratory

Claims (4)

[Claims] 1. The following equation 1: (Wherein, R ¹ and R ² independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or a carbon atom having 2 carbon atoms)
And R ³ and R ⁴ independently represent an alkyl group having 1 to 50 carbon atoms or an alkenyl group having 2 to 50 carbon atoms, and m and n each independently represent 0 to 10. And represents an integer of from 50 to 50).
A lubricating composition satisfying the C standard and having biodegradability. 2. The following equation 1: (Wherein, R ¹ and R ² independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or a carbon atom having 2 carbon atoms)
And R ³ and R ⁴ independently represent an alkyl group having 1 to 50 carbon atoms or an alkenyl group having 2 to 50 carbon atoms, and m and n each independently represent 0 to 10. To an integer of 50 to 50), and comprises an ISO EG
A lubricating composition satisfying the D standard and having biodegradability. 3. The lubricating composition according to claim 1, comprising 15 to 90% by weight of the ester compound represented by the formula 1. 4. An ester compound according to claim 1, wherein R ³ and R ⁴ independently represent an alkyl group having 7 to 30 carbon atoms or an alkenyl group having 7 to 30 carbon atoms. A lubricating composition according to any one of the preceding claims.