JPH05194980A - Two-cycle engine oil composition - Google Patents

Abstract

PURPOSE:To obtain the subject composition excellent in the capability of high- temperature cleaning required in attendance with the improvement in the performance of a two-cycle engine. CONSTITUTION:The objective composition comprises 0.6-6wt.% alkaline earth metal alkylsalycilate (A) of a base number of 100mgKOH/g or below, 30-99wt.% neopentylic polyol ester (B) prepared by reacting a 5-12 C neopentylic polyol with a 4-18 C organic acid. This composition has an excellent capability of cleaning at high temperatures by the synergistic action of component A of a relatively low base number as a metallic cleaning agent with component B comprising the polyol ester of a specified structure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-cycle engine oil composition capable of maximizing cleanliness under high temperature conditions.

[0002]

2. Description of the Related Art In recent years, the popularity of motorbikes has rapidly increased due to the rise of motor sports. Sports bikes are often equipped with a two-cycle engine, so the performance of the engine itself is improving.
As the performance of the engine is improved, the two-cycle engine oil is required to have excellent cleanliness so that the ring groove, the periphery of the piston and the exhaust port are minimized. Conventionally, as a two-cycle engine oil composition, from the viewpoint of seizure resistance, detergency and combustibility, a composition containing a mineral oil, polybutene, kerosene, a metal type detergent, etc. as a main component is known. There is.

[0003]

However, the conventional mineral oils or those containing polybutene as a main component as described above have a problem that their cleanliness and seizure resistance are slightly inferior. Also,
In consideration of detergency, neutral and basic phenates or sulfonates have been used as metallic detergents used up to now, but these metallic detergents do not always have satisfactory detergency at high temperatures. This should not be the case, and with the recent improvement in the performance of two-cycle engines, there has been a demand for two-cycle engine oil compositions that exhibit superior performance due to their cleanliness at high temperatures.

It is an object of the present invention to provide a two-cycle engine oil composition which is excellent in high-temperature cleanability, which is required as the performance of the recent two-cycle engine is improved.

[0005]

DISCLOSURE OF THE INVENTION As a result of intensive studies to achieve the above object, the inventors of the present invention have found that a two-cycle engine oil consisting of a synthetic oil having specific properties and a specific metal type detergent. They found that the composition meets the purpose, and completed the present invention.

The two-cycle engine oil composition of the present invention comprises:
Based on this finding, (A) base number 100 mg KO
Neopentyl produced by the reaction of an alkaline earth metal salt of alkylsalicylic acid of H / g or less at 0.6 to 6% by weight, and (B) a neopentyl type polyol having 5 to 12 carbon atoms and an organic acid having 4 to 18 carbon atoms. Type polyol ester 3
It is characterized by containing 0 to 99% by weight.

One preferred embodiment of the composition of the present invention is a mineral lubricating oil having a kinematic viscosity at 100 ° C. of about 4 to 40 cSt or a purified product thereof (hereinafter, mineral oil) and 100.
A base number of 100 mgK with respect to a lubricating base oil selected from among synthetic lubricating base materials having a kinematic viscosity at 4 ° C of 4 to 40 cSt
OH / g or less of an alkaline earth metal salt of alkylsalicylic acid (hereinafter referred to as component A) is blended at a ratio of about 0.6 to 6% by weight, preferably about 1 to 3% by weight, and a carbon number of 5 to 1
A neopentyl type polyol ester (hereinafter, referred to as B component) produced by the reaction of the neopentyl type polyol of 2 and an organic acid having 4 to 18 carbon atoms is blended in a ratio of about 30 to 99% by weight, preferably about 33 to 80% by weight. It will be done. However, in the composition of the present invention, not only the above-mentioned mineral oil but also a synthetic lubricating oil base material other than the component (B) is not necessarily required.

The neopentyl type polyol ester as the component (B) which is one of the constituents of the composition of the present invention is a neopentyl type polyol having 5 to 12 carbon atoms, preferably 5 to 9 carbon atoms, and 4 to 18 carbon atoms, preferably 6 carbon atoms. Made by reaction with ~ 12 organic acids. If the number of carbon atoms of these polyols or organic acids is too small or too large, the detergency does not increase so much.

The above-mentioned neopentyl type polyol is a polyhydric alcohol having a neopentyl structure.
2,2-Dimethyl-propane-1,3-diol (ie neopentyl glycol), 2-ethyl-2-butyl-propane-1,3-diol, 2,2-diethyl-propane-1,3-diol , 2-methyl-2-propyl-propane-1,3-diol, trimethylolethane, trimethylolpropane, trimethylolbutane, pentaerythritol and the like can be used, preferably neopentyl glycol, 2-methyl-2-propyl- Propane-1,3-diol, trimethylolpropane,
Pentaerythritol is preferable, and neopentyl glycol, trimethylolpropane, and pentaerythritol are particularly preferable.

The above-mentioned organic acid is, for example, n
-Butanoic acid, i-butyric acid, n-pentanoic acid, i-valeric acid,
n-hexanoic acid, 2-ethylbutanoic acid, i-hexanoic acid, hexahydrobenzoic acid, n-heptanoic acid, i-heptanoic acid, methylhexahydrobenzoic acid, n-octanoic acid, dimethylhexanoic acid, 2-ethylhexanoic acid, Two
4,4-trimethylpentanoic acid, i-octanoic acid, 3,
5,5-trimethylhexanoic acid, n-nonanoic acid, i-nonanoic acid, i-decanoic acid, i-undecanoic acid, 2-butyloctanoic acid, tridecanoic acid, tetradecanoic acid, hexadecanoic acid, octadecanoic acid, etc. can be used. Preferably n-
Heptanoic acid, i-heptanoic acid, n-octanoic acid, and 2-ethylhexanoic acid.

The neopentyl type polyol ester can be synthesized from these organic acids and the neopentyl type polyol by a conventionally known method, for example, a dehydration condensation method in the presence of an acidic catalyst. Examples of the neopentyl type polyol ester in the composition of the present invention (hereinafter, neopentyl glycol is abbreviated as NPG, trimethylolpropane as TMP, and pentaerythritol as PE) are, for example, NPG di- (heptanoate), NPG di- (2 -Ethyl butyrate), NPG
.Di- [mixture (hexanoate, heptanoate)],
TMP tri- (pentanoate), TMP tri-
(Hexanoate), TMP · tri- [mixed (butyrate, octadecanoate)], TMP · tri- [mixed (hexanoate, heptanoate, octanoate)], PE · tetra (pentanoate), PE and C 4-8 Esters with a mixture of linear or branched carboxylic acids can be mentioned. Also, NPG, TMP and PE
Other than neopentyl type polyols, namely 2-methyl-2-propyl-propane-1,3-diol, 2,2
-Diethyl-propane-1,3-diol, trimethylolethane, neopentyl-type polyol ester of trimethylolhexane and the above organic acids alone or as a mixture. In the composition of the present invention, the blending ratio of the above neopentyl type polyol ester is about 30-9.
It is 9% by weight, preferably about 33 to 80% by weight, and if it is less than this, cleanability at high temperature becomes poor.

Further, the alkaline earth metal salt of alkyl salicylic acid having a base number of 100 mgKOH / g or less (hereinafter, also referred to as "salicylate") of the component (A) in the composition of the present invention is a so-called metallic detergent. If the base number is too high, the cleanability at high temperature will be poor. Here, the alkyl group preferably has 1 to 50 carbon atoms, and the alkaline earth metal is preferably Ca, Mg, Ba or the like. Alkaline earth metal salts of alkylsalicylic acid have various base numbers, but in the composition of the present invention, in order to improve the above high temperature detergency, in particular, a base number of about 100 mgKOH / g or less,
Preferably less than about 60 mg KOH / g is used. If the base number is too low, the addition amount must be increased, which is economically disadvantageous.
It is preferable that the lower limit value is about KOH / g. Alkaline earth metal salts of alkylsalicylic acid having such a base number are specifically calcium dodecylsalicylate, calcium dodecylmethylsalicylate, calcium cetylsalicylate, calcium cetylmethylsalicylate, calcium octylsalicylate, calcium i-octylsalicylate, Examples thereof include calcium dicetyl salicylate and calcium dioctyl salicylate. The above-mentioned alkaline earth metal salt of alkylsalicylic acid can be generally obtained by first alkylating phenol with α-olefinic acid, then introducing a carboxyl group by Kolbe-Schmidt reaction, and then performing metathesis reaction or the like. The proportion of the alkaline earth metal salt of alkylsalicylic acid is about 0.6 to 6% by weight, preferably about 1 to 3% by weight. If the blending ratio is too small, the effect is not recognized, and conversely if the blending ratio is too large, the effect is saturated and it is economically disadvantageous.

In the composition of the present invention, the above (A),
In addition to the component (B), polybutene or the like may be added to obtain a smoke eliminating effect, and kerosene or the like may be added to obtain a combustion supporting effect. Furthermore, various other various effects may be obtained to obtain other various effects. Additives, such as ashless dispersants and pour point depressants, can also be added. Examples of the ashless dispersant include succinimide, succinic acid ester, benzylamine, etc. to which an alkyl group or alkenyl group having a molecular weight of about 700 to 3000 is added, and succinimide borated. used. Polymethacrylate or the like is used as the pour point depressant. The amount of each of these additives to be added is about 20% by weight or less, preferably about 0.
5-10% by weight is suitable.

[0014]

The two-cycle engine oil composition of the present invention contains an alkaline earth metal salt of alkyl salicylic acid having a relatively low base number as a metal type detergent and a polyol ester having a specific structure. Due to the presumed synergistic effect, it exhibits excellent cleanability at high temperatures,
This effect is unknown. However, compared with the conventional metal type detergent, the alkaline earth metal salt of alkylsalicylic acid used in the present invention has a low base number because the amount of metal is reduced by the amount of salicylate component, which results in high temperature. It is presumed that it contributes to the cleanliness below in some way.

[0015]

EXAMPLES Examples and comparative examples of the composition of the present invention will be given below, but the composition of the present invention is not limited to these examples. Examples 1 to 6 and Comparative Examples 1 to 5 Six types of compositions of the present invention shown in Table 1 were prepared. The general property values of these six kinds of compositions of the present invention are as shown in Table 2. The Mg salicylate used to prepare the composition of Example 3 in Table 1 was prepared by first adding phenol with 12 carbon atoms.
Alkylation with α-olefin, followed by introduction of carboxyl group by Kolbe-Schmidt reaction to give a Mg salt by metathesis reaction. The amount of Mg is about 1.6% by weight and the base number is about 45 mgKOH / g. Met. With respect to the above 6 types of the present invention, the following test method
A high temperature cleanability test and an engine test were conducted, and the test results are also shown in Table 1.

(Panel caulking test) Federal
Evaluation was carried out by a panel caulking method according to test method 791B • 3462. The test method was as follows: a panel temperature of 300 ° C. and an oil temperature of 80 ° C. were operated for 3 hours in a cycle of splash for 15 seconds and stop for 45 seconds, and the amount of carbon deposited on the panel surface (panel coking) (mg) was high. It is a method to evaluate with.

(High temperature cleanliness test) A commercially available 50 cc separated refueling system (gasoline specification) two cycle engine was used,
It was operated for 50 hours under operating conditions of 7,000 rpm (full load), and the cleanliness of the piston was evaluated by a merit rating (point evaluation) (10: best, 0: worst).

Also, five comparative compositions shown in Table 3 were prepared. Comparative Examples 1, 2, and 4 are those in which the carbon number of the organic acid of pentaerythritol ester is increased (note that Comparative Example 4 is added with mineral oil), and Comparative Example 3 is the alkaline earth metal salt of alkylsalicylic acid. Base number is 160mgKOH
/ G, and Comparative Example 5 is a commercial product. These comparative compositions were subjected to the same panel caulking test and high temperature detergency test as those of the composition of the present invention, and the test results are also shown in Table 3. As is clear from Tables 1 and 3, the compositions of the present invention are superior to the comparative compositions in high-temperature detergency.

[0019]

[Table 1]

[0020]

[Table 2]

[0021]

[Table 3]

[0022]

As described above in detail, according to the two-cycle engine oil composition of the present invention, the alkyl earth metal salt of alkylsalicylic acid having a specific base number and a specific neopentyl type polyol ester blended in a specific ratio. The synergistic effect with the can significantly improve the cleanability of the engine at a high temperature as compared with the conventional oil composition of this type.

[Procedure amendment]

[Submission date] December 19, 1992

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be amended] Title of invention

[Correction method] Change

[Correction content]

Title of invention Two-cycle engine oil composition

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Claims (1)

[Claims] 1. An alkaline earth metal salt of alkylsalicylic acid having a base number of 100 mgKOH / g or less (0.6 to 6% by weight), and (B) a neopentyl type polyol having 5 to 12 carbon atoms and 4 to 18 carbon atoms. A two-cycle engine oil composition comprising 30 to 99% by weight of a neopentyl-type polyol ester prepared by the reaction with the organic acid.