JPH10121082A - Marine engine oil composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a marine engine oil composition being excellent in the ability to neutralize the formed sulfuric acid and improved in the ability to prevent corrosion and abrasion. SOLUTION: This composition is prepared by adding 1-30 mass % overbased alkaline earth metal phenate having a basicity (as determined by the hydrochloric acid method) and a basicity (as determined by the perchloric acid) each of which is 300-400mgKOH/g and having a ratio of the former to the latter of 0.95 or above, 0.5-15 mass % overbased alkaline earth metal salicylate having a basicity of above 200 to 350mgKOH/g and 0.5-15 mass % overbased alkaline earth metal salicylate having a basicity of 100-200mgKOH/g and 0.1-5 mass % nonionic surfactant to a base oil comprising a mineral oil, a synthetic lubricating oil or a mixture of both.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a marine engine oil composition, and more particularly, to a marine diesel engine using a high sulfur fuel, which has a maximum capacity in a field where corrosion resistance to sulfuric acid is required. The present invention relates to a marine engine oil composition that can be used only to a maximum extent.

[0002]

2. Description of the Related Art Generally, heavy oil containing a large amount of sulfur is used as fuel used in marine diesel engines. May be used. A large amount of sulfur oxides (hereinafter referred to as SOx) will be contained in the combustion exhaust gas when using the fuel containing these high sulfur contents. This SOx reacts with the moisture present in the surroundings to form sulfuric acid, which may cause parts such as engine components to corrode and wear. For this reason, marine engine oils are required to have the ability to suppress corrosion and wear caused by sulfuric acid. In conventional marine engine oils, it has been understood that a large amount of sulfuric acid can be neutralized by adding a fixed amount of a high base number overbased metal type detergent, thereby suppressing the corrosive wear of cylinder liners and piston rings. .

[0003]

In a marine diesel engine, there is a possibility that a high-sulfur degraded fuel may be used in the future, and as a result, sulfate oxide in the exhaust gas increases, and It is thought that the sulfuric acid generated in the above also increases. In order to neutralize this sulfuric acid, it is conceivable to add a high base number overbased metal type detergent. However, a high base number overbased metal type detergent used in conventional marine cylinder oil is considered. Simply increasing the amount of the agent may not sufficiently neutralize sulfuric acid, and there may be a tendency for corrosion wear of cylinder liners, piston rings, and the like to increase. Accordingly, an object of the present invention is to provide a marine engine oil composition that has excellent neutralizing properties for the generated sulfuric acid and improves the prevention of corrosion and abrasion.

[0004]

SUMMARY OF THE INVENTION The present inventors have found that in the above marine diesel engines, such as crosshead and trunk piston engine oils, a high base number, overbased metal type detergent is used in a cylinder. Focusing on being the largest factor in suppressing the corrosion wear of liners and piston rings, and as a result of studying this corrosion wear phenomenon, a high base number overbased metal By blending a specific nonionic surfactant as an additive with the detergent, they found that an engine oil composition having the optimum performance of preventing corrosion and abrasion of cylinder liners and piston rings was obtained. Diesel engine oil composition "(JP-A-5-239485). In addition, an engine oil composition which has abrasion resistance and high detergency and exhibits good low-temperature fluidity by blending a specific amount of a specific calcium phenate and a specific calcium salicylate as an overbased metal type detergent. And found an "engine oil composition" (Japanese Patent Application No. 7-11 / 1997).
No. 5316). The present inventors have further studied the corrosion and abrasion phenomenon from the viewpoint of sulfuric acid neutralization, and as a result, have found that a specific overbased alkaline earth metal phenate and two types of overbased alkali sulfides having different base numbers. By mixing a specific amount of the earth metal salicylate and the nonionic surfactant, it is possible to obtain a marine engine oil composition having an optimum cylinder liner and piston ring corrosion-prevention property as in the above invention. The present invention has been newly found, and the present invention has been completed.

That is, the marine engine oil composition of the present invention comprises (A) a base number measured by a hydrochloric acid method and a base number measured by a perchloric acid method in a base oil of mineral oil or synthetic lubricating oil or a mixture of both. Both 300-400mgKOH /
g of an overbased alkaline earth metal phenate having a ratio of 0.95 or more to the former, (B) a base number exceeding 200 mg KOH / g, and
0.5 to 15% by mass of an overbased alkaline earth metal salicylate of not more than mg KOH / g, and (C) a base number of 100 to 2
It is characterized by containing an overbased alkaline earth metal salicylate of 00 mg KOH / g in an amount of 0.5 to 15% by mass and (D) a nonionic surfactant in an amount of 0.1 to 5% by mass. A marine engine oil composition is provided.
Hereinafter, the present invention will be described in detail.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The overbased alkaline earth metal phenate of the component A in the present invention has a base number of 300 to 40.
0 mgKOH / g, preferably 350-400 mgKO
H / g, and the ratio of the base number measured by the hydrochloric acid method to the base number measured by the perchloric acid method is 0.95 or more, preferably 0.98 to 1.0. When the base number ratio is less than 0.95, stable basicity may not be obtained,
Further, the neutralization becomes unstable, and a sufficient effect of suppressing corrosion wear may not be obtained. Overbased alkaline earth metal phenates include overbased calcium phenate, overbased barium phenate, and overbased strontium phenate.
Various overbased alkaline earth metal phenates can be used, including overbased magnesium phenate, but overbased calcium phenate is preferred. As the overbased calcium phenate, various overbased calcium phenates can be used, and overbased sulfurized calcium phenate is particularly preferred. Also, A
The properties of the component overbased alkaline earth metal phenate are as follows:
Usually, the viscosity at 100 ° C. is 40 to 1000 mm ² /
s, the hue (ASTM color) is L3.0 to 8.0 Dil, and the fatty acids are 0.1 to 50% by mass of the total amount. The production method is described in detail in JP-A-7-113095.

[0007] Overbased sulfurized alkaline earth metal phenates include phenols, dihydric alcohols, alkaline earth metal oxides or hydroxides or mixtures thereof (hereinafter referred to as alkaline earth metal reagents) and sulfur. It is obtained by reacting the added product or a product obtained by adding water thereto, and then subjecting a distillation column bottom obtained by distilling off an excess amount of dihydric alcohol and at least an excess amount of water to carbon dioxide treatment. . In a preferred embodiment of the overbased sulfurized alkaline earth metal phenate, in the above-mentioned method for producing an overbased sulfurized calcium phenate, 0.001 to 0.7 mol of fatty acids per 1 mol of alkaline earth metal reagent is used at the latest. Overbased calcium sulfide phenate obtained by performing carbon dioxide treatment in the presence of 0.01 to 0.9 mole of water per mole of alkaline earth metal reagent, which is present before the carbon treatment.

The raw materials used in producing the overbased sulfurized alkaline earth metal phenate are as follows.
As phenols, hydrocarbon side chains having 4 to 36 carbon atoms, preferably 8 to 32 carbon atoms, for example, an alkyl group,
Phenols having an alkenyl group, an aralkyl group and the like can be mentioned. Specifically, it is derived from hydrocarbon groups such as butyl, amyl, octyl, nonyl, dodecyl, cetyl, ethylhexyl, and triacontyl, or liquid hydrocarbons such as liquid paraffin, wax, and olefin polymers (polyethylene, polypropylene, polybutene, etc.). The phenols having a group are used alone or in a mixture thereof. Usually about 130 ° C, preferably about 120 ° C
What can become liquid below is desirable.

As the alkaline earth metal reagent, an oxide or hydroxide of an alkaline earth metal or a mixture thereof is usually used. For example, oxides or hydroxides such as calcium, barium, strontium, and magnesium are used. The amount of the alkaline earth metal reagent used relative to the phenol is 0.00 per mole of the phenol used.
It is 1 to 0.99 mol, preferably 0.01 to 0.98 mol. If the amount of the alkaline earth metal reagent relative to the phenol is too large, the intermediate gels and the reaction does not proceed any further, so that the desired good product cannot be obtained. On the other hand, if the amount is too small, not only does the yield of the product relative to the raw material decrease, but also the utility and time spent for recovering the phenols increase.

Next, as the dihydric alcohol, one having a relatively low boiling point, low viscosity and high reactivity is used. The dihydric alcohol preferably has 2 to 6 carbon atoms, particularly preferably ethylene glycol, propylene glycol and the like. The dihydric alcohol assists and stabilizes the conversion of the phenols to the oil-soluble substance by the reaction of the phenols with the alkaline earth metal reagent, and is partially incorporated into the product phenate to constitute multi-equivalent phenate. In the method of the present invention,
The metal addition reaction may be performed with or without the addition of water having a reaction promoting effect.
The amount of the dihydric alcohol used is about 0.15 to 3.0 moles, particularly about 0.3 to 1.5 moles per mole of the alkaline earth metal reagent.
Molar is preferred. When the reaction is performed without adding water, the amount of the dihydric alcohol to be used is preferably about 1.0 to 3.0 mol, particularly preferably about 1.2 to 2.0 mol, per 1 mol of the alkaline earth metal reagent. If the amount of the dihydric alcohol is too small, the product conversion of the reaction raw materials, particularly the alkaline earth metal reagent, is reduced. The time and utility for distilling off the dihydric alcohol is excessive. The amount of sulfur used is 0.001 to 3.0 mol, preferably 0.01 to 1 mol per mol of the alkaline earth metal reagent.
To 0.5 mol, more preferably 0.1 to 0.4 mol. As the amount of sulfur used decreases, the viscosity of the product decreases, but if it is too large, not only does it make it difficult to obtain a product with a high base number because the overbasing of the product decreases, but also the viscosity of the product becomes extremely high As a result, it is impossible to obtain the desired product having a low viscosity and a high base number.

When water is added to the reaction system to promote the reaction in the metal addition reaction of the alkaline earth metal reagent to the phenols, not only distilled water but also canned water, industrial water, and metal addition reaction are used. The quality of the water is not particularly limited, and water in any state such as cold water, hot water, and steam can be used. The water used for promoting the metal addition reaction may be added to the reactor alone with water, or part or all of the water may be added as a mixture with other raw materials such as phenols and dihydric alcohols. The timing of adding water to the reactor is not particularly limited, and may be before or after all of the reaction materials other than water are mixed, but it is preferable to add the water within about one hour after mixing all of the reaction materials. The amount of water used for promoting the metal addition reaction in the reaction system is about 0.01 to 10 mol, preferably 0.1 to 2.0 mol, per 1 mol of the alkaline earth metal reagent used. When the metal addition reaction is carried out by adding water from the outside to the reaction system, the reaction proceeds smoothly compared to the case where the reaction is carried out under the same conditions except that water is not added, and the reaction raw materials, particularly the alkaline earth metal reagent, Product conversion rate increases. Therefore, if the amount of water added to the reaction system is too small, the product conversion of the alkaline earth metal reagent will decrease. Conversely, if the amount is too large, the advantage that the distillation step after the reaction is simplified is lost.

The addition of water coexisting during the carbon dioxide treatment involves reacting a raw material mixture comprising phenols, dihydric alcohols, alkaline earth metal reagents and sulfur, or water to this. After completion of the metal sulfide addition reaction, distillation is generally carried out after distilling off water and excess dihydric alcohol. There is no limitation on the quality and state of the water coexisting during the carbon dioxide treatment, similarly to the water used for promoting the metal addition. The amount of water in the reaction system is from 0.01 to 0.9 mol, preferably from 0.05 to 0.9 mol, per mol of the alkaline earth metal reagent.
It is adjusted to 0.6 mol, more preferably 0.1 to 0.5 mol. If there is an excess of dihydric alcohol in the system, any water in the system such as water added at the time of distillation and water generated by the reaction is distilled off as a forerunner. After distilling off the excess, it is necessary to add a predetermined amount of water. On the other hand, when there is no excess dihydric alcohol in the system, a predetermined amount of water present in the system after the reaction is completed, such as water added for promoting the reaction before the metal sulfide addition reaction or water generated during the reaction. Although only the excess water may be removed and only the excess is distilled off, if the remaining amount is unclear, it is preferable to add a predetermined amount of water after once distilling off the entire amount of water.

[0013] As the amount of water coexisting during carbon dioxide treatment increases, the base number of the product increases,
If the amount is too large, the product is excessively hydrolyzed, causing a decrease in base number and oil solubility. If the amount is too small, the effect of improving the base number of the product cannot be sufficiently obtained. Fatty acids to be present before the carbon dioxide treatment are fatty acids having 10 to 30 carbon atoms, preferably 16 to 24 carbon atoms, or salts thereof, and in the case of salts, alkaline earth metal salts are preferable. Also,
It is even more preferred if the alkyl group portion is linear.
Specific examples include decanoic acid, capric acid, lauric acid, palmitic acid, stearic acid, behenic acid, lignoceric acid, cerotic acid, montanic acid, and melicic acid, and preferably stearic acid. The amount of fatty acids ranges from 0.001 to 1 mol per mole of alkaline earth metal reagent.
0.7 mole, preferably 0.01 to 0.7 mole.
If the amount of the fatty acid to be added is small, the base number of the phenate is not further improved, and the hue and the oil solubility are reduced. If it is too large, the base number will decrease.

In the present invention, a diluent or a solvent (hereinafter, referred to as a diluent) having an appropriate viscosity can be added to facilitate handling of a reactant, a reaction intermediate, or a product. For example, when recovering excess unreacted phenols from the reaction product after completion of the metal addition reaction step or carbon dioxide treatment by distillation, the reaction should be performed at a high boiling point and in the presence of a diluent having an appropriate viscosity. As a result, the bottom of the reaction column can be obtained in a desired liquid state. Note that, usually, a part of the diluent is also distilled off as the unreacted phenols are distilled off. Therefore, when repeatedly using the recovered phenols for the reaction, a diluent that does not directly affect the reaction is desirable. The reaction may be performed in the presence of a diluent. Examples of preferred diluents include petroleum fractions of appropriate viscosity such as paraffinic, naphthenic, aromatic, or mixed base oils, for example, a boiling point of about 220-550 ° C and a viscosity of about 2 × at 100 ° C. 10 ^-6 ~
A lubricating oil fraction of 4 × 10 ⁻⁵ m ² / s can be mentioned. Other organic solvents also exhibit hydrophobicity and lipophilicity, and can be used as a diluent if they are harmless at the time of reaction or in the application of the product. For example, higher alcohols having 8 to 24 carbon atoms can be used.

The main production steps and operating conditions for the overbased sulfurized alkaline earth metal phenate in the present invention are as follows. The metal sulfide addition reaction step includes phenols, dihydric alcohols, alkaline earth metal reagents, sulfur,
Alternatively, the reaction is performed using fatty acids and / or water added thereto. Temperature about 60-200 ° C, preferably about 90
The reaction is carried out in the range of -190 ° C. The pressure is not particularly limited, and is in the range of 0.01 to 21 atm.A, preferably 0.1 to 21 atm.
１１11 atm · A is selected. This reaction is usually carried out from 1 to 9
It almost finishes within the time range.

In the carbon dioxide treatment step, after completion of the metal addition reaction, excess dihydric alcohol and at least excess water in the system are distilled off, and if no fatty acid is added first, or if the fatty acid added first is removed. If the amount is small,
After adding fatty acids to a predetermined amount and allowing a predetermined amount of water to exist in the system, the reaction temperature is about 50 to 230 ° C.
Preferably, it is reacted with carbon dioxide under a temperature condition of 80 to 200 ° C. This reaction may be performed under reduced pressure, normal pressure, or increased pressure. Usually, a range of 0.01 to 51 atm.A, preferably 0.1 to 31 atm.A is employed. The reaction is generally carried out until the absorption of carbon dioxide is substantially stopped, and is for 20 minutes to 10 hours, usually 20 minutes to 3 hours.
The product obtained here may be further subjected to 0 to 20 atm. G, preferably 0 to 10 atm.
It is maintained at a pressure of G at about 100 to 230 ° C. for several minutes to several tens of hours. The carbon dioxide treatment further improves the performance of the product as a lubricating oil additive and a fuel oil additive, in particular, oil solubility and stability in engine oil when added to engine oil. The timing of adding the fatty acids may be any time from the time of addition of the raw materials to the reactor and before the carbon dioxide treatment step, but is preferably before the addition of water to be added during the carbon dioxide treatment.

An alkaline earth metal reagent and a dihydric alcohol or, if necessary, a fatty acid are added to the reaction product after the carbon dioxide treatment, and the above-mentioned metal addition reaction is carried out again. Is repeated once or more to further add a metal. It is preferable to recover a part or most of the unreacted phenols in the reaction product after the carbon dioxide treatment, and the recovered phenols can be reused as a raw material. If the unreacted phenols are distilled in the presence of a normal diluent such as a high-boiling mineral oil, the distillation residue can be obtained in a preferable liquid form. Insoluble substances in the distillation residue can be removed by an operation such as filtration or centrifugation before or after the recovery of phenols. The compounding ratio of the overbased sulfurized alkaline earth metal phenate of the component A, which is one of the essential components in the present invention, is 1 to 30% by mass, and preferably 1 to 20% by mass. If the compounding amount is 1% by mass or less, a sufficient base number cannot be obtained, and the effect is reduced.
If the amount is more than mass%, the effect is not improved only by giving an excessive base number.

The overbased alkaline earth metal salicylate of component B, which is one of the essential components in the present invention, has a base number exceeding 200 mgKOH / g and 350 mgKOH / g.
And particularly preferably 250 mgKOH / g to 3 mg
50 mgKOH / g. Further, the overbased alkaline earth metal salicylate of component C, which is one of the essential components in the present invention, has a base number of 100 to 200 mgKOH / g, preferably 150 to 200 mgKOH / g. The above alkaline earth metal salicylates include calcium salts and magnesium salts, but are preferably calcium salts. Component B is an α-olefin having 20 to 30 carbon atoms, component C is an α-olefin having 14 to 18 carbon atoms, and phenol is alkylated to form an alkyl metal salt.
A product obtained by introducing a carboxyl group by a Schmidt reaction and converting it into an alkaline earth metal salt by metathesis or the like is used (see Japanese Patent Publication No. 61-24560, Japanese Patent Publication No. 61-24651, etc.). The overbased type is produced by treating the neutral type with carbon dioxide.

The mixing ratio of the overbased alkaline earth metal salicylate is 0.5 to 15% by mass, preferably 0.5 to 10% by mass. If the proportion of the overbased alkaline earth metal salicylate is too small, the effect is not sufficient, and if it is too large, the effect cannot be improved for the added amount. The mixing ratio of the overbased alkaline earth metal phenate of the component A, the overbased alkaline earth metal salicylate of the component B, and the overbased alkaline earth metal salicylate of the component C is as follows. A: (B +
C) = 10: 1 to 1: 1 and preferably 7: 1 to 1
1: 1. The mixing ratio of the component B and the component C is B: C = 1: 4 to 4: 1, preferably B: C = 1: 2 to 2: 1 in terms of the base number ratio of each component.

Further, the non-ionic surfactant of component D, which is one of the essential components in the present invention, has, for example, a C8-C8 surfactant.
Having an alkylamine having an alkyl group of 22;
Polyoxyalkylene alkylamine to which 10 mol of alkylene oxide has been added; polyoxyethylene alkyl or alkenyl ether having an alkyl or alkenyl group having 10 to 20 carbon atoms and having 1 to 20 mol of ethylene oxide added thereto; Polyoxyethylene alkyl phenyl ether having 1 to 20 moles of ethylene oxide having up to 30 alkyl groups;
Having from 20 to 20 alkyl or alkenyl groups, from 1 to 20
Polyoxypropylene alkyl or alkenyl ether to which moles of propylene oxide has been added;
A polyoxybutylene alkyl or alkenyl ether having 20 alkyl or alkenyl groups and 1 to 20 moles of butylene oxide added thereto; having an alkyl or alkenyl group having 10 to 20 carbon atoms, and a total of 1 to 30 moles Nonionic surfactants having ethylene oxide and propylene oxide or ethylene oxide and butylene oxide added thereto; higher fatty acid alkanolamides or alkylene oxide adducts thereof;
And fatty acid glycerin monoester composed of a fatty acid having 10 to 20 carbon atoms and glycerin.

As the polyoxyalkylene type nonionic surfactant, a polyoxyethylene nonionic surfactant having an alkyl group having 1 to 30 carbon atoms is particularly preferable because the raw material can be easily obtained. Specific examples of the polyoxyethylene nonionic surfactant include, for example, polyoxyethylene lauryl ether, polyoxyethylene higher alcohol ether, polyoxyethylene nonyl phenyl ether, polyoxyethylene octyl phenyl ether,
Polyoxyethylene octyl stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate, polyoxyethylene glycol monooleate, and the like, preferably polyoxyethylene nonyl phenyl ether, Polyoxyethylene lauryl ether, polyoxyethylene higher alcohol ether, and polyoxyethylene octyl phenyl ether. When a nonionic surfactant is blended, the dispersion state of the basic alkaline earth metal phenate is improved,
The neutralization reactivity between the mixed sulfuric acid and the basic alkaline earth metal phenate is improved. The compounding amount of the nonionic surfactant in the marine engine oil composition of the present invention is from 0.1 to 5
%, Preferably 0.1 to 1% by mass. If the amount of the nonionic surfactant is too small, the effect is reduced, and if it is too large, the effect cannot be improved.

In the present invention, the above component A, component B,
The components C and D are mixed with a base oil comprising a mineral oil-based lubricating oil, a synthetic lubricating oil or a mixture of both. The base oil has a normal lubricating oil viscosity, and preferably has a viscosity index of 85 to 140. In the case of a mineral oil-based lubricating oil, a mineral oil-based lubricating oil fraction may be used by purifying it by appropriately combining solvent refining, hydrorefining, and the like. As synthetic lubricating oils, for example, α-olefin oligomers which are polymers of α-olefins having 3 to 12 carbon atoms, dialkyl diesters having 4 to 12 carbon atoms such as sebacate such as dioctyl sebacate, azelate, adipate and the like. Polyol esters including esters obtained from 1-trimethylolpropane, pentaerythritol and a monobasic acid having 3 to 12 carbon atoms, 9 to 4 carbon atoms
And alkylbenzenes having 0 alkyl group. The mineral lubricating oil and the synthetic lubricating oil can be used alone or in combination of two or more.

In the engine oil composition of the present invention, in addition to the above-mentioned additives, various known additives may be used, if necessary, for example, ashless dispersants such as alkenylsuccinimide or derivatives thereof, dialkyldithioline Zinc thiophosphate such as zinc acid, 2,6-di-tert-butyl-p
-Various antioxidants such as phenolic compounds such as cresol, aromatic amine compounds such as N-dimethylaniline, various antiwear agents such as molybdenum dialkyldithiophosphate, polymethacrylates, ethylene-propylene copolymer, styrene / isoprene Copolymer, styrene
Various viscosity index improvers such as hydride of isoprene copolymer or polyisobutylene, various extreme pressures such as sulfurized fats and oils, diphenyl sulfide, methyl trichlorostearate, chlorinated naphthalene, iodinated benzyl, fluoroalkyl polysiloxane, lead naphthenate Agents, carboxylic acids including stearic acid, dicarboxylic acids, metal soaps,
Various rust inhibitors such as carboxylic acid amine salts, heavy sulfonic acid metal salts, polyhydric alcohol carboxylic acid partial esters and phosphate esters, various friction modifiers such as higher fatty acids, higher alcohols, amines and esters, silicone oils Such defoamers may be used alone or in combination of two or more. In addition to these, various additives can be appropriately compounded.

The method for preparing the engine oil composition of the present invention is as follows.
The base oil, the essential components and various additives may be appropriately mixed as necessary.The order of mixing is not particularly limited, and the essential components may be sequentially mixed with the base oil. After mixing, it may be mixed with the base oil. Further, various additives may be added to the base oil in advance, or may be added to essential components. The base number of the marine engine oil composition of the present invention obtained by blending the above components is 5 to 100.
mgKOH / g, preferably 10-70 mgKO
H / g. Further, the marine engine oil composition of the present invention is suitable for a marine diesel engine using a high sulfur content fuel. The high sulfur content fuel referred to herein is a Japanese industrial standard K-2205 which is a domestic standard. The specified kinematic viscosities are 1 to 3 and the sulfur content is No. 1 to 3. Specifically, the sulfur content is in the range of 0.5 to 3.5%, and further includes heavy oil of 3.5% or more supplied outside.

[0025]

Next, the present invention will be described in more detail with reference to examples. However, the present invention is not limited at all by these examples. In the examples, an essential component and various additives were blended with a base oil to prepare an engine oil composition, and a sulfuric acid neutralization test, piston cleanliness, and corrosion of a piston ring were evaluated. The types of base oils, essential components and additives used in the preparation of the engine oil compositions of the respective examples and comparative examples, and the respective evaluation tests are as follows.

(1) Base oil SAE40 (American Society of Automotive Engineers has an automotive lubricant having a viscosity number of 40 and a kinematic viscosity at 100 ° C. of 12.
A base oil having a viscosity index of 100 and a mineral oil of 5 to 16.3 mm ² / s) was used. (2) Calcium phenate A (TBN 350 mg KO
H / g) 552.21 g (2.1 mol) of 99.75% pure dodecylphenol and 41.38 g of calcium oxide having 94.9% purity were placed in a 1-liter autoclave equipped with a stirrer, a gas inlet tube and a thermometer. (0.7 mol) and 6.74 g (0.21 mol) of sulfur (0.3 mol per mol of calcium oxide), 4.98 g (0.01 mol) of stearic acid
(75 mol) (0.025 mol per mol of calcium oxide) and stirred. To the obtained suspension, 65.20 g (1.05 mol) of ethylene glycol was added at 125 ° C., and this was added at 130 ° C. under a pressure of about 3.0 atm. After stirring for a period of time, the generated water, some unreacted ethylene glycol and a small amount of dodecylphenol were distilled off while gradually reducing the pressure in the reaction system, whereby 618.3 g of a liquid distillation residue was obtained. . The final distillation temperature at this time was 140 ° C. (3 mmHg). Next, 5.04 water was added to 618.3 g of the distillation residue.
g (0.28 mol) (0.1 mol per mol of calcium oxide).
4 mol), and then from the reduced pressure at a temperature of 150 ° C.
Carbon dioxide was absorbed for 0 minutes. At this time, the supply rate of carbon dioxide to the autoclave was 0.315 liter /
min. Then, the temperature was raised to 178 ° C., and the pressure was again increased with carbon dioxide until the gauge pressure reached 5.0 atm.
After holding for a time, 648.3 g of a reaction product was obtained. To 648.3 g of the reaction product, 117.37 g of 150 neutral oil was added as a diluent. 698.27 g of this reaction product was transferred to a 1-liter three-necked pear-shaped flask, and distilled under reduced pressure to distill off a small amount of ethylene glycol and most of unreacted dodecylphenol. The distillation residue was 182.35.
g was obtained. The final distillation temperature at that time is 225 ° C. (1.5 m
mHg). Then, the distillation residue was diluted with a large amount of hexane, and 12.59 g of insoluble matter was obtained by centrifugation.
After removal of hexane, an overbased sulfurized calcium phenate obtained by distilling and removing a large amount of hexane was used. The properties are shown below. Properties (i) Base value Hydrochloric acid method 352 mg KOH / g Perchloric acid method 352 mg KOH / g (ii) Ratio of base numbers (hydrochloric acid method / perchloric acid method) 1.0 (iii) Fatty acid amount 2.8% by mass (iv) Viscosity (100 ° C.) 432 mm ² / s (v) Hue (ASTM color) * L3.0 Dil *: Performed according to the method specified in JIS-K-2580 (Petroleum product color test method).

(3) Calcium salicylate B (TBN)
(300 mgKOH / g) A phenol was alkylated with an α-olefin having 20 to 30 carbon atoms, and then a carboxyl group was introduced by a Kolbe-Schmidt reaction, and then a calcium salt was obtained by metathesis or the like. (4) Calcium salicylate C (TBN 170 mgK
OH / g) A phenol was alkylated with an α-olefin having 14 to 18 carbon atoms, and then a carboxyl group was introduced by a Kolbe-Schmidt reaction, and then a calcium salt was obtained by metathesis or the like. (5) Polyoxyethylene-based nonionic surfactant As a polyoxyethylene-based nonionic surfactant,
Polyoxyethylene nonyl phenyl ether was used.

(6) Alkenyl succinimide A polyolefin having a molecular weight of 30 to 3000 is reacted with maleic anhydride and then imidized using a polyamine, or an imide obtained is reacted with an aromatic polycarboxylic acid. Some of the remaining amino groups are amidated (for example, polybutene having a molecular weight of 900 is reacted with maleic anhydride, and then imidized with tetraethylenepentamine, or is reacted with trimellitic acid. And the like were used. (7) Antifoaming agent A silicone antifoaming agent (commercially available additive) was used. (8) Commercial calcium phenate (i) Base number hydrochloric acid method 175 mgKOH / g Perchloric acid method 250 mgKOH / g (ii) Ratio of base number (hydrochloric acid method / perchloric acid method) 0.7

Evaluation Test (1) Sulfuric Acid Neutralizing Test 10.0 g of the compositions of Examples and Comparative Examples as test oils were put into a branch-equipped 300 ml Myer flask and heated. When the temperature of the test oil reached 50 ° C., 0.15 ml of concentrated sulfuric acid equivalent to 30 mg KOH / g was added and stirred,
2 minutes with a fine differential pressure gauge set in a flask, 4
And the CO ₂ generation pressure after 6 minutes were measured, and C per hour was measured.
It is evaluated that the higher the O ₂ generation pressure, the more the corrosion wear can be suppressed. (2) Evaluation of Piston Cleanliness and Corrosion Wear of Piston Rings A 2.2-liter, single-cylinder, diesel engine with an engine speed of 1500 rpm and a test time of 10
After continuous operation for 0 hours, after the test, cleanliness of the piston and corrosion wear of the cylinder liner and the piston ring were evaluated. The fuel oil at this time was JI with a sulfur content of 2.5%.
S, a type equivalent to No. 3 type 1 was used.

Examples 1 to 11 The above base oils contained calcium phenate A, calcium salicylate B, calcium salicylate C, and a polyoxyethylene-based nonionic surfactant in proportions shown in Tables 1, 2 and 3 (% by mass). ) To prepare a marine engine oil composition. The results of the sulfuric acid neutralization test of the obtained marine engine oil composition are as shown in Tables 1, 2 and 3 below. Note that the balance in the table means that the amount of the base oil is selected such that the total amount of each component blended in the engine oil is 100% by mass.

Comparative Examples 1-4 A marine engine oil composition was prepared by blending the above base oils and additives. The mixing ratio (% by mass) is shown in the upper part of Table 4, and the result of the sulfuric acid neutralization test is shown in the lower part of Table 4. Example 12 and Comparative Examples 5 and 6 Calcium phenate A, calcium salicylate B, calcium salicylate C, polyoxyethylene-based nonionic surfactant (polyoxyethylene nonylphenyl ether), alkenyl A marine engine oil composition was prepared by mixing a succinimide and an antifoaming agent in the proportions (% by mass) shown in Table 5, and using a bench engine, the corrosion and wear evaluation of a cylinder liner and a piston ring and piston cleanliness were performed. An evaluation was performed. Table 5 shows the results.
Shown in The evaluation results in Table 5 show that Comparative Example 6 was 1.0
It was shown as a ratio when

[0032]

[Table 1]

[0033]

[Table 2]

[0034]

[Table 3]

[0035]

[Table 4] W. T. D: Total demerit rating T. G. FIG. F: Top ring groove clogging

[0036]

[Table 5]

[0037]

The marine engine oil composition of the present invention comprises a specific overbased alkaline earth metal sulfide and two overbased alkaline earth metal salicylates having different base numbers. By adding a nonionic surfactant, the corrosion resistance to sulfuric acid is improved.
It also has high cleanliness. The marine engine oil composition of the present invention is extremely useful in practical use.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C10N 30:04 30:12 40:25 (72) Inventor Ken Suzuki 1134-2 Gongendo, Satte City, Saitama Kosmo Research Institute, Ltd. Inside the R & D Center (72) Inventor Hayashi Kimura 1134-2 Gongendo, Satte City, Saitama Prefecture R & D Center, Cosmo Research Institute, Inc.

Claims (1)

[Claims] 1. The base oil of mineral oil or synthetic lubricating oil or a mixture of both has (A) a base number measured by a hydrochloric acid method and a base number measured by a perchloric acid method of 300 to 400 mg.
KOH / g, the ratio of the former to the latter being 0.95
The overbased alkaline earth metal phenate described above is
30% by mass, (B) 0.5 to 15% by mass of an overbased alkaline earth metal salicylate having a base number exceeding 200 mg KOH / g and 350 mg KOH / g or less, and (C) a base number of 100 to 200 mg KOH / g. 0.5 to 15% by mass of an overbased alkaline earth metal salicylate, and (D)
A marine engine oil composition comprising 0.1 to 5% by mass of a nonionic surfactant.