JPH06240276A - Lubricating oil composition for two-cycle engine - Google Patents

Abstract

(57) [Summary] [Structure] A lubricating oil composition for a two-cycle engine of the present invention comprises a lubricant base oil, a polyamide dispersant of 5% by weight to 25% by weight, a neutral calcium sulfonate and a neutral calcium salicylate. The amount is 0.1 to 5% by weight. [Effects] The composition of the present invention is a lubricating oil composition that is excellent in high-temperature detergency and has low low-temperature viscosity, and is suitable as a lubricating oil composition for two-cycle engines such as for outboard motors or chainsaws. In particular, it is suitable as a lubricating oil composition used in a so-called separated lubrication system in which fuel and lubricating oil are mixed in a two-cycle engine.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a lubricating oil for a two-cycle engine, which is excellent in cleanability at high temperature, can be made low in viscosity at low temperature, is excellent in miscibility with gasoline, and is excellent in biodegradability and seizure resistance. It relates to a composition.

[0002]

2. Description of the Related Art Engine oils containing inexpensive mineral oil as a base oil and optionally containing a cleaning agent and an antiwear agent are widely used, but in two-cycle engines for motorcycles, outboard motors, etc. In addition to miscibility with gasoline as a function of lubricating oil and anti-seizure property, is required to have biodegradability as awareness of environmental problems increases. That is, in order to prevent pollution of lakes and marshes due to unburned lubricating oil discharged from a two-cycle engine, it has high engine oil performance that can ensure the required performance even with a small amount of use, and even if discharged, it can easily be used by aquatic organisms. There is a need for a biodegradable lubricating oil that is degraded.

The present applicant has previously proposed a lubricating oil composition for a two-cycle engine which is excellent in biodegradability, gasoline miscibility, and seizure resistance (Japanese Patent Application No. 4-13940).
No. 5) In a so-called separated lubrication system in which fuel and lubricating oil are mixed in a two-cycle engine, from the viewpoint of fluidity of lubricating oil at low temperature, miscibility with gasoline, and cleanability at high temperature. However, there is still room for improvement.

[0004]

DISCLOSURE OF THE INVENTION The present invention provides a lubricating oil composition which is excellent in applicability in a wide temperature range, that is, which is excellent in cleanability at high temperature and has a low viscosity at low temperature, which makes the composition miscible with gasoline. An object is to provide an excellent lubricating oil composition for a two-cycle engine.

[0005]

A two-cycle engine lubricating oil composition of the present invention comprises a lubricating base oil containing 5% to 25% by weight of a polyamide dispersant, a neutral calcium sulfonate and a neutral calcium salicylate. It is characterized in that the total amount is 0.1% to 5% by weight.

The lubricant base oil component used in the present invention includes polyol ester, diester, petroleum solvent, polybutene, polymethacrylate, mineral oil, poly-α.
-Olefin and the like. First, the polyol ester includes polyol esters of an aliphatic polyhydric alcohol and a linear or branched fatty acid. Examples of the aliphatic polyhydric alcohol forming the polyol ester include neopentyl glycol, trimethylolpropane, ditrimethylolpropane, trimethylolethane, ditrimethylolethane, pentaerythritol, dipentaerythritol, tripentaerythritol, and the like. As the fatty acid, those having 16 to 24 carbon atoms can be used, and preferred fatty acids are heptadecyl acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid and the like. Further, partial esters of the above-mentioned aliphatic polyhydric alcohol and linear or branched fatty acid can also be used. These partial esters can be obtained by appropriately adjusting the number of reaction moles of the aliphatic polyhydric alcohol and the fatty acid to react.

These polyol esters have a temperature of 100 ° C.
Kinematic viscosity at 9 to 15 cSt, preferably 11 to 14 c
It is made of St, has excellent biodegradability, and is used as a lubricating base oil. If the viscosity is less than 9 cSt, the seizure resistance is inferior, and if it exceeds 15 cSt, the biodegradability deteriorates.

The polyol ester may be present in the base oil in an amount of 30% by weight to 70% by weight, preferably 40% by weight to 60% by weight. If it is less than 30% by weight, seizure resistance tends to decrease. If it exceeds 70% by weight, the miscibility with gasoline will decrease.

Next, the diester is a linear or branched aliphatic dibasic acid having 6 to 10 carbon atoms as a carboxylic acid component, specifically, adipic acid, pimelic acid, suberic acid, and azelaic acid. , Sebacic acid, and those having properties equivalent to these. The alcohol component is an aliphatic alcohol having 6 to 10 carbon atoms, and specific examples thereof include hexyl alcohol, heptyl alcohol, octyl alcohol, nonyl alcohol, decyl alcohol, and isomers thereof.

The diester has a kinematic viscosity at 100 ° C. of 2 to
It is 5 cSt, preferably 2 to 4 cSt, and is added for the purpose of improving miscibility with gasoline. If it exceeds 5 cSt, the dilutability deteriorates.

The diester should be present in an amount of 30% to 70% by weight, preferably 40% to 50% by weight.
When it is less than 0% by weight, miscibility with gasoline becomes poor, and when it exceeds 70% by weight, seizure resistance is deteriorated.

The petroleum solvent has a boiling point range of 130 ° C. to 300 ° C. under normal pressure, and is, for example, JISK2.
203 or a light fraction of hydrogenated mineral oil, which has a viscosity equivalent to kerosene, that is, a kinematic viscosity at 100 ° C. of 4 cSt or less, preferably 2 cSt or less, and is added for the purpose of improving miscibility with gasoline. To be done. If it exceeds 4 cSt, the dilutability deteriorates.

The petroleum-based solvent may be present in an amount of 40% by weight or less, preferably 10% by weight to 25% by weight. If it exceeds 40% by weight, the viscosity is lowered and the seizure resistance is deteriorated.

Polybutene has a molecular weight of 500 to 2500,
Preferably 500-1500, more preferably 700-
It is 1000 and is added as a heavy base oil component for the purpose of preventing seizure, and when the molecular weight exceeds 2500, the effect of improving seizure resistance becomes small.

Polybutene is added in an amount of 1 to 5% by weight, preferably 1.5 to 3.5% by weight, and 5% by weight is added.
If it exceeds, from the viewpoint of viscosity adjustment, there is a problem that the amount of the low-viscosity diester compounded increases, resulting in a decrease in seizure resistance.

In the present invention, polymethacrylate may be used instead of polybutene. Polymethacrylate has a molecular weight of 5,000 to 40,000, preferably 10,000 to 20,000, and is added as a heavy base oil component for the purpose of preventing seizure. If the molecular weight exceeds 40,000, it will be resistant. The effect of improving seizure becomes small.

The polymethacrylate may be of a dispersed type or a non-dispersed type, and examples thereof include those having the following structures.

[0018]

[Chemical 1]

In the above formula, R is a hydrocarbon group having 1 to 18 carbon atoms, R'is hydrogen or a methyl group, X is a polar group, and n is 10
Indicates an integer of ˜1000.

Polymethacrylate is added in an amount of 1 to 5% by weight, preferably 2 to 5% by weight, and 5% by weight is added.
If it exceeds, there is a problem that the cleanliness deteriorates. Also, polybutene may be added together with polymethacrylate.

Other base oils for two-cycle engine oils include mineral oil and poly-α-olefins. Examples of the mineral oil include 30 neutral oil, 100 neutral oil, 150 neutral oil, 300 neutral oil, 500 neutral oil, etc., which have been solvent-refined or hydrogenated-refined, and low-temperature fluidity improved by removing wax from these base oils. There are pour point base oils and the like, and these can be used alone or in admixture at an appropriate ratio.

As the poly-α-olefins,
It is obtained by any one homopolymer or two or more copolymers selected from olefin hydrocarbons having or not having a branch in the range of 2 to 14 carbon atoms,
It is selected from products having an average molecular weight of 100 to about 2000, but those in which unsaturated bonds have been removed by hydrogenation are preferred.

Among the above base oils, 30% by weight to 70% by weight of a polyol ester having a kinematic viscosity at 100 ° C. of 9 to 15 cSt.
% By weight, 30% by weight to 70% by weight of diester having a kinematic viscosity at 100 ° C. of 2 to 5 cSt, 1 to 5% by weight of polybutene having a molecular weight of 500 to 2500 and / or molecular weight of 5,0.
100 to 40,000 polymethacrylate 1% by weight to 5
It is preferably composed by weight% from the viewpoint of biodegradability, seizure resistance, and high-temperature cleanability.

In the lubricating oil composition of the present invention, 5% to 25% by weight of a polyamide dispersant as a dispersant, 0.1% by weight to 5.0% by weight of a total amount of neutral calcium sulfonate and neutral calcium salicylate. It is characterized by containing by weight%. Polyamide-based dispersants are generally excellent in detergency, but are poor in heat resistance as compared with succinimide dispersants, and, for example, detergency at high temperatures is deteriorated. However, in the present invention, in addition to this polyamide-based dispersant, a neutral calcium sulfonate and a neutral calcium salicylate in a total amount of 0.1% by weight to 5.0% by weight are contained, whereby cleaning at high temperature is achieved. It has been found that, in addition to excellent properties, the viscosity at low temperature can be lowered, and the gasoline miscibility can be excellent.

The polyamide dispersant is an ashless type, for example, Lubrizol 39 manufactured by Lubrizol Co., Ltd.
0, Lubrizol 397, Lubrizol 398, Oronite 340R manufactured by Oronite Japan KK, and Oronite RB. The amount of polyamide dispersant added is 5
% To 25% by weight, preferably 10 to 20% by weight.

The neutral calcium sulfonate added together with the polyamide-based dispersant is, for example, trade name Lubrizol 65 (manufactured by Lubrizol Co., Ltd.), PARANOX.
-24 [manufactured by Exxon Chemical Co., Ltd.], Ca-Petr
ona [manufactured by Witco Chemical Co., Ltd.], OLOA246
B [manufactured by Caronite Chemical Co., Ltd.], TLA256 (manufactured by Texaco Co., Ltd.) and the like can be used, and as neutral calcium salicylate, for example, trade name SAP002 (manufactured by Shell Chemical Co., Ltd.) can be used. The total amount of the neutral calcium sulfonate and the neutral calcium salicylate is 0.1 to 5% by weight, preferably 0.5 to 3.0% by weight. The weight ratio of and is preferably 8: 2 to 2: 8. If the total amount of the neutral calcium sulfonate and the neutral calcium salicylate exceeds 5.0% by weight, it becomes a deposit and is not preferable.

In addition, a rust preventive agent, an antifoaming agent, a metal detergent, an antiwear agent, an antioxidant, a pour point depressant and the like are added to the composition of the present invention as required. Further, the lubricating oil composition for a two-cycle engine of the present invention can be used even in a low oil mixing specification up to a mixing ratio of 100: 1 with gasoline.

[0028]

In the composition of the present invention, a diester is added to a lubricating base oil, particularly a polyol ester for the purpose of miscibility with gasoline, and a polybutene and / or a polybutene is used for the purpose of preventing seizure. Methacrylate is added and both the polyol ester and diester are excellent in biodegradability, but by adding a polyamide-based dispersant as a dispersant, and further neutral calcium sulfonate and neutral calcium salicylate, a wide temperature range can be obtained. The applicability, that is, the cleanliness at high temperature and the viscosity at low temperature can be reduced, and the gasoline miscibility can be excellent.

Thus, the lubricating oil composition of the present invention is suitable as a lubricating oil composition for two-cycle engines such as for outboard motors or chainsaws, and in particular, a fuel and lubricating oil are mixed in a two-cycle engine. It is suitable as a lubricating oil composition used in a so-called separated lubrication system. Hereinafter, the present invention will be described with reference to examples.

[0030]

Example 1 A sample oil 1 of the present invention having the following composition was prepared.

(1) Esterification product of 1 mol of trimethylolpropane and 3 mol of C ₁₈ monocarboxylic acid (viscosity 13 cSt, 100 ° C.) ... 42.2% by weight (2) Adipic acid and C ₈ monoalcohol Esterified product (viscosity 2.5 cSt, 100 ° C.) 38.5 wt% (3) Polybutene [molecular weight 1500, 750 cSt (100 ° C.)] 1.8 wt% (4) Polyamide-based ashless dispersant ( Trade name Lubrizol 397, manufactured by Lubrizol Co., Ltd. ・ ・ ・ 15.0 wt% (5) Neutral calcium sulfonate (trade name Ca-Petrona, manufactured by Witco Chemical Co., Ltd.) ・ ・ ・ 1.5 wt% (6 ) Neutral calcium salicylate (trade name SAP002, manufactured by Shell Kagaku Co., Ltd.) 1.0 wt%

[0032]

Example 2 A sample oil 2 of the present invention having the following composition was prepared.

(1) Esterified product of 1 mol of trimethylolpropane and 3 mol of C ₁₈ monocarboxylic acid (viscosity 13 cSt, 100 ° C.) ... 42.0% by weight (2) Adipic acid and C ₈ monoalcohol Esterified product (viscosity 2.5 cSt, 100 ° C.) 38.3 wt% (3) Polybutene [molecular weight 800, 120 cSt (100 ° C.)] 1.8 wt% (4) Polyamide-based ashless dispersant ( Trade name Lubrizol 397, manufactured by Lubrizol Co., Ltd.) ・ ・ ・ 15.0% by weight (5) Neutral calcium sulfonate (trade name TLA256, manufactured by Texaco Co.) ・ ・ ・ 1.9% by weight (6) Neutral calcium Salicylate (Brand name SAP002, Shell Chemical Co., Ltd.) ・ ・ ・ 1.0% by weight

[0034]

Example 3 A sample oil 3 of the present invention having the following composition was prepared.

(1) Esterification product of 1 mol of trimethylolpropane and 3 mol of C ₁₈ monocarboxylic acid (viscosity 13 cSt, 100 ° C.) 32.5% by weight (2) Adipic acid and C ₈ monoalcohol Esterified product (viscosity 2.5 cSt, 100 ° C.): 46.9 wt% (3) Polymethylmethacrylate [molecular weight 20,000]: 1.8 wt% (4) Polyamide-based ashless dispersant (trade name) Lubrizol 397, manufactured by Lubrizol Co., Ltd .... 15.0% by weight (5) Neutral calcium sulfonate (trade name Lubrizol 65, manufactured by Lubrizol Co., Ltd .... 2.8% by weight (6) Neutral calcium salicylate (Product name SAP002, manufactured by Shell Chemical Co., Ltd.) ... 1.0% by weight

[0036]

Example 4 A sample oil 4 of the present invention having the following composition was prepared.

(1) Esterification product of 1 mol of trimethylolpropane and 3 mol of C ₁₈ monocarboxylic acid (viscosity 13 cSt, 100 ° C.) 33.0% by weight (2) Adipic acid and C ₈ monoalcohol Esterified product (viscosity 2.5 cSt, 100 ° C.) ・ ・ ・ 47.5 wt% (3) Polymethylmethacrylate [molecular weight 10,000] ・ ・ ・ 1.8 wt% (4) Polyamide ashless dispersant (trade name) Lubrizol 397, manufactured by Lubrizol Co., Ltd .... 15.0% by weight (5) Neutral calcium sulfonate (trade name PARANOX 24, manufactured by Exxon Chemical Co., Ltd.) 1.7% by weight (6) Neutral calcium Salicylate (Brand name SAP002, Shell Chemical Co., Ltd.) ・ ・ ・ 1.0% by weight

[0038]

Example 5 A sample oil 5 of the present invention having the following composition was prepared.

(1) Esterification product of 1 mol of trimethylolpropane and 3 mol of C ₁₈ monocarboxylic acid (viscosity 13 cSt, 100 ° C.) ... 63.5% by weight (2) Kerosene (boiling point range 150 ° C. to 250 ° C.) ) ・ ・ ・ 17.5 wt% (3) Polybutene [Molecular weight 800, 120 cSt (100 ° C.)] ・ ・ ・ 1.5 wt% (4) Polyamide-based ashless dispersant (trade name Lubrizol 397, manufactured by Lubrizol Co., Ltd.) ) 15.0% by weight (5) Neutral calcium sulfonate (trade name Ca-Petrona, manufactured by Witco Chemical Co., Ltd.) 1.5% by weight (6) Neutral calcium salicylate (trade name SAP002, Shell Chemical Co., Ltd. ・ ・ ・ ・ ・ ・ (1) High temperature detergency and (2) Low temperature viscosity were measured for each lubricating oil composition prepared at 1.0 wt% or more. Was Tsu. Next, the composition of the comparative oil used in this measurement together with the sample oil of the present invention will be described.

[Comparative Oil 1] (1) Esterification product of 1 mol of trimethylolpropane and 3 mol of C ₁₈ monocarboxylic acid (viscosity 13 cSt, 100 ° C.) ... 43.4% by weight (2) Adipic acid and C ₈ Esterified product with monoalcohol (viscosity 2.5 cSt, 100 ° C.) 39.7 wt% (3) Polybutene [Molecular weight 1500, 750 cSt (100 ° C.)] 1.9 wt% (4) Polyamide Ashless dispersant (trade name Lubrizol 397, manufactured by Lubrizol Co., Ltd.) 15.0% by weight [Comparative oil 2] (1) Esterification product of 1 mol of trimethylolpropane and 3 mol of C ₁₈ monocarboxylic acid ( viscosity 13cSt, 100 ℃) ··· 39.6 wt% (2) adipic acid and C ₈ monoalcohol and the ester (viscosity 2.5 cSt, 100 ° C.) · · · 6.2 wt% (3) Polybutene [Molecular weight 1500, 750 cSt (100 ° C)] ・ ・ ・ 1.7 wt% (4) Succinimide ・ ・ ・ 20.0 wt% (5) Neutral calcium sulfonate (commodity) Name Ca-Petrona, manufactured by Witco Chemical Co., Ltd. ・ ・ ・ 1.5% by weight (6) Neutral calcium salicylate (trade name SAP002, manufactured by Shell Chemical Co., Ltd.) ・ ・ ・ 1.0% by weight [Comparative oil 3] (1) Ester compound of 1 mol of trimethylolpropane and 3 mol of C ₁₈ monocarboxylic acid (viscosity 13 cSt, 100 ° C.) 40.9% by weight (2) Ester of adipic acid and C ₈ monoalcohol Compound (viscosity 2.5 cSt, 100 ° C.) 37.3 wt% (3) Polybutene [Molecular weight 1500, 750 cSt (100 ° C.)] 1.8 wt% (4) 20.0 wt% succinimide · now be described measuring method. High temperature cleanliness is
Evaluation was performed using a hot tube test (HTT) manufactured by Komatsu Ltd. HTT has an inner diameter of 2 mm and a length of 300 m
Air flow rate of 10 ± 0.5 cc / m
in. , Oil flow rate 0.31 ± 0.01 cc / h, temperature condition 280 ± 1 ° C., after passing each sample oil and comparative oil for 16 hours, wash the glass tube with n-hexane and dry sufficiently. After that, stain the glass tube with a hot tube test score sample to give a color score (0-10
(Point: perfect score), and the higher the value, the better the cleanliness.

The low temperature viscosity is a value obtained by measuring the Brookfield viscosity (cP) at −10 ° C. based on TCW II which is a regulation for outboard motors. The lower the value, the better the low temperature viscosity. Hereinafter, Table 1 shows the respective measurement results for the sample oil of the present invention and the comparative oil.

[0042]

[Table 1]

As can be seen from the table, the two-cycle engine oil of the present invention is excellent in high temperature detergency and low in low temperature viscosity.

Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI Technical display location C10N 10:04 30:00 A 8217-4H Z 8217-4H 30:02 30:04 30:08 40:26

Claims (1)

[Claims] 1. A lubricating base oil comprising 5% to 25% by weight of a polyamide dispersant, 0.1% by weight to 5% by weight of a total amount of neutral calcium sulfonate and neutral calcium salicylate.
A lubricating oil composition for a two-cycle engine, which is blended by weight.