KR20190018185A - Lubricating oil additive composition and method for preparing the same - Google Patents

Abstract

According to an embodiment of the present invention, a lubricant composite additive which is added to lubricant base oil to form a lubricant, comprises 0.02 mass % or more of an organic molybdenum compound by molybdenum (Mo), and 0.5 mass % of complex ester, with respect to a lubricant. The complex ester is obtained through an esterification reaction between at least one multi-functional alcohol and at least one multi-functional carboxylic acid, and a chain termination agent, wherein (a) the multi-functional alcohol is a hindered or uncharged aliphatic polyol, (b) the multi-functional carboxylic acid includes an aliphatic dicarboxylic acid of 9 to 18 carbon atoms, a dimerization and/or a trimerization fatty acid or a mixture thereof, wherein the dimerization and trimerization fatty acids do not exceed 80% by weight of the total amount of the multi-functional carboxylic acid; (c) the chain termination agent includes an aliphatic monocarboxylic acid selected from the group consisting of a straight chain saturated acid having 7 to 22 carbon atoms, a branched saturated acid having 7 to 24 carbon atoms, a straight or branched unsaturated acid having 16 to 24 carbon atoms, and a mixture thereof, or one or more aliphatic straight or branched saturated or unsaturated mono-functional alcohols having 14 or more carbon atoms; and (d) the kinematic viscosity at 100° C of the produced complex ester is 30 to 1,000 cSt.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a novel additive for environmentally friendly new material lubricants and a method for manufacturing a novel additive for environmentally friendly new material lubricants.

The present invention relates to a synthetic additive for environmentally friendly new material lubricants and a method for producing the additive for environmentally friendly new material lubricants. More particularly, the present invention relates to a synthetic lubricant additive and a lubricant additive excellent in abrasion- .

Recently, there has been a great demand for improving the fuel efficiency of automobiles to prevent global warming, and to suppress the emission of CO2. In order to improve the fuel efficiency of the automobile, the efficiency of the engine is important. On the other hand, reducing the friction of the engine contributes to the improvement of the fuel efficiency. Therefore, the use of the low friction material as the sliding part and the adoption of the fuel saving engine oil have been promoted.

In addition, the world is suffering from pollution caused by fine dust and becoming increasingly serious, the government is actively promoting efforts to reduce marine pollution as well as automobile pollution with local governments. It is a reality that need an alternative engine oil to realize.

As the fuel economy engine oil, it is classified into 5W-30 and 0W-30 viscosity grades as specified in SAE (American Automobile Manufacturers Association) J300, and as an additive (friction modifier, hereinafter also referred to as FM) It is known that mixing an organic molybdenum-based FM such as molybdenum dithiocarbamate (MoDTC) is effective.

However, it is known that sulfuric acid is produced from sulfur or sulfur in fuel and engine oil, and a part of the produced sulfuric acid is contained in the engine oil, so that the engine member is corroded and abraded. Therefore, even when MoDTC or the like is blended, engine oil excellent in corrosion resistance is strongly desired.

Japanese Patent Application Laid-Open No. 2008-106199 Japanese Laid-Open Patent Publication No. 2008-518080

It is an object of the present invention to provide a method for manufacturing a lubricant oil additive and a lubricant oil additive excellent in corrosion resistance, abrasion resistance, and fuel economy.

Another object of the present invention is to provide a synthetic lubricant additive and a method for manufacturing a lubricant synthetic additive which can significantly reduce fine dust by drastically reducing the exhaust efficiency by significantly improving the output efficiency.

Other objects of the present invention will become more apparent from the following detailed description and the accompanying drawings.

According to one embodiment of the present invention, the lubricant oil additive which is added to the lubricant base oil to form the lubricant oil contains 0.02% by mass or more of molybdenum (Mo) and 0.5% or more by mass of the complex ester based on the lubricating oil, Wherein the complex ester is obtained through esterification and chain terminating agents between one or more polyfunctional alcohols and at least one polyfunctional carboxylic acid, wherein (a) the polyfunctional alcohol is a hindered or non-hindered aliphatic Polyol, and (b) the polyfunctional carboxylic acid comprises an aliphatic dicarboxylic acid having 9 to 18 carbon atoms, a dimerization and / or a trimerized fatty acid or a mixture thereof, provided that the dimerized and trimerized fatty acid has a multifunctional (C) the chain stopper is a linear saturated acid having 7 to 22 carbon atoms, a branched saturated hydrocarbon having 7 to 24 carbon atoms, An aliphatic monocarboxylic acid selected from the group consisting of an acid, a linear or branched unsaturated acid having from 16 to 24 carbon atoms, and mixtures thereof, or an aliphatic monocarboxylic acid selected from the group consisting of one or more aliphatic straight or branched aliphatic saturated or unsaturated monocarboxylic acids having 14 or more carbon atoms (D) the resulting complex ester has a kinematic viscosity at 100 DEG C of 30 to 1000 cSt.

The polyfunctional alcohol may be neopentylpolyol.

The polyfunctional alcohol may be trimethylolpropane or pentaerythritol.

The organic molybdenum compound may be molybdenum dithiocarbamate (MoDTC).

According to an embodiment of the present invention, there is provided a method for producing a lubricating oil additive added to a lubricating base oil to form a lubricating oil, comprising: mixing the organic molybdenum compound with 0.02 mass% or more of molybdenum (Mo) (A) a polyfunctional alcohol is a hindered or non-hindered aliphatic polyol, and (b) at least one polyfunctional carboxylic acid and at least one polyfunctional carboxylic acid, (b) the polyfunctional carboxylic acid comprises an aliphatic dicarboxylic acid having 9 to 18 carbon atoms, a dimerization and / or a trimerized fatty acid or a mixture thereof, provided that the dimerized and trimerized fatty acid is a polyfunctional carboxylic acid (C) the chain stopper is a linear saturated acid having 7 to 14 carbon atoms, a branched saturated acid having 7 to 24 carbon atoms, a carbon number of 16 or less An aliphatic monocarboxylic acid selected from the group consisting of linear, branched or unbranched unsaturated acids and mixtures thereof, or at least one aliphatic linear or branched saturated or unsaturated monocarboxylic acid having at least 14 carbon atoms and no more than 24 carbon atoms (D) the kinetic viscosity of the complex ester at 100 캜 is 0 to 200 cSt.

According to the embodiment of the present invention, even when used for a long period of time, corrosion and abrasion of the engine member are small, and furthermore, low friction characteristics are excellent.

Hereinafter, preferred embodiments of the present invention will be described in more detail. The embodiments of the present invention can be modified in various forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. The embodiments are provided to explain the present invention to a person having ordinary skill in the art to which the present invention belongs.

As the lubricant base oil used in one embodiment of the present invention, any of mineral oil, synthetic oil, and mixtures thereof can be used. As a mineral oil, a high viscosity index lubricant base oil having a viscosity index of 120 or more is preferable. A high viscosity index lubricating oil base oil having a viscosity index of 120 or more can be obtained by subjecting a product oil obtained by hydrogen isomerization of wax or hydrocracking of a heavy oil to solvent removal or hydrogenation dewaxing.

The hydrogen isomerization of the wax may be carried out by using a slack wax obtained in a solvent dewaxing process of a wax having a boiling range of 300 to 600 ° C and a carbon number of 20 to 70, for example, a mineral oil- And a wax obtained by a Fischer-Tropsch synthesis in which a liquid fuel is synthesized by hydrogen is used as a raw material, and a hydrogen isomerization catalyst such as a Group 8 metal such as nickel or cobalt on a silica-alumina carrier, Molybdenum, tungsten, or the like, a catalyst in which platinum or the like is supported on a zeolite catalyst or a zeolite-containing support, and a catalyst having a hydrogen partial pressure of 5 to 14 MPa, Temperature, LHSV (liquid space velocity) of 0.1 to 2 hours. At this time, it is preferable that the conversion of linear paraffins is 80% or more and the conversion to hard distillate is 40% or less.

On the other hand, a lubricating oil base oil having a high viscosity index using hydrogenolysis of heavy oil can be obtained as follows. Pressure filtration oil or bright stock having a boiling point in the range of 300 to 600 占 폚 subjected to hydrodesulfurization and denitrification as required may be introduced into a hydrocracking catalyst such as a hydrocracking catalyst such as a cobalt At a temperature of 350 to 450 DEG C, at a temperature in the range of 0.1 to 2 h < -1 > in the presence of hydrogen at a hydrogen partial pressure of 7 to 14 MPa, (Liquid space velocity), and it is preferable that the decomposition rate (mass% in which the distillate fraction of 360 DEG C or more occupying the product is reduced) is 40 to 90%.

The hard distillate is distilled off from the hydrogen isomerization-producing oil or the hydrogenation-cracking-producing oil obtained in the above method to obtain a lubricating oil distillate. The distillate generally has a high pour point or viscosity and a high viscosity index Therefore, the wax is removed to remove the wax, and a lubricant base oil having a% CP of 80 or more, a pour point of -10 占 폚 or less and a viscosity index of 120 or more by ndM ring analysis can be obtained.

When this wax component is removed by solvent dewaxing, distillation is carried out using a precision distillation apparatus at the time of distillation removal of the hard distillate, and distillation at a boiling point of 371 ° C or higher and lower than 491 ° C by gas chromatography distillation It is preferable to cut to 70 mass% or more in order to perform the solvent dewaxing treatment more efficiently. The solvent dewaxing treatment is carried out at a temperature of -15 to -40 占 폚 in the range of solvent / oil ratio of 2/1 to 4/1 by using methyl ethyl ketone / toluene (volume ratio of 1/1) .

On the other hand, when the removal of the wax component is carried out by the hydrogenation degassing process, the distillation of the hard distillation fraction is carried out to such an extent that it does not interfere with the hydrogenation desorption, and the distillation is carried out using a precision distillation apparatus after the hydrogenation- It is efficient and preferable to cut such that the distillate fraction having a boiling point of 371 DEG C or more and less than 491 DEG C is 70 mass% or more. The hydrodewaxing is contacted with a zeolite catalyst in the presence of hydrogen at a hydrogen partial pressure of 3 to 15 MPa at a temperature of 320 to 430 ° C, LHSV (liquid space velocity) of 0.2 to 4 h-1, Of -10 占 폚 or less.

In this way, a lubricating oil base oil having a viscosity index of 120 or more can be obtained, but solvent purification or hydrogenation purification can be performed again as desired.

Examples of synthetic oils include diesters synthesized from dicarboxylic acids such as oligomers of? -Olefins and adipic acid, monoesters of polyhydric alcohols such as neopentyl glycol, trimethylol propane and pentaerythritol, and monobasic acids , And a mixture thereof.

Mixed oils combining a suitable mineral oil and a synthetic oil may also be used as the base oil of the present engine oil.

Mineral oils, synthetic oils, or mixed oils thereof, when used in the fuel economy engine oil composition of the present invention, has a kinematic viscosity at 100 ° C of 4.5 mm 2 / s or less and a viscosity index of 120 or more by the method defined in JIS K2283 The kinematic viscosity at 100 ° C is 1.0 mm 2 / s or more, the% CP by ndM ring analysis in the method specified in ASTM D2140 is 80 or more, and the pour point by the method defined in JIS K2269 is -10 ° C or less, More preferable.

The fuel economy engine oil composition of the present invention contains 0.02 mass% or more of molybdenum (Mo) as the amount of the organic molybdenum compound based on the total amount of the engine oil composition. If it is less than 0.02 mass%, sufficient fuel economy saving continuity can not be obtained. The organic molybdenum compound is preferably contained in an amount of 0.03 to 0.20 mass% as the amount of molybdenum (Mo).

Specific examples of the organic molybdenum compound include molybdenum dithiocarbamate (MoDTC), molybdenum dithiophosphate (MoDTP), Mo amine complex, and the like. Of these, MoDTC is the most preferable, and MoDTP is not preferable because phosphorus poisoned the three-way catalyst of exhaust gas purification.

The complex ester according to an embodiment of the present invention is preferably obtained through an esterification reaction between one or more polyfunctional alcohols and at least one polyfunctional carboxylic acid and a chain terminator.

Preferable polyfunctional alcohols include hindered polyols, more preferably neopentyl polyols. Examples of suitable neopentyl polyols include neopentyl glycol, dipentaerythritol, trimethylol propane and pentaerythritol, with trimethylol propane and pentaerythritol being particularly preferred.

The polyfunctional carboxylic acid preferably comprises at least one aliphatic dicarboxylic acid having 9 to 12 carbon atoms, more preferably selected from nonanoic acid, decanedioic acid, dodecanedioic acid, and mixtures thereof. The presence of the dimerized and / or trimerized fatty acid is considered to be advantageous when the amount of the fatty acid does not exceed 80% by weight, and preferably does not exceed 50% by weight of the total amount of the polyfunctional carboxylic acid. The dimerization and / or trimerization fatty acids can be obtained by heat treatment of the unsaturated fatty acid-containing feedstock in the presence of a suitable catalyst well known in the art to dimerize it. Suitable unsaturated fatty acid-containing raw materials generally comprise a mixture of unsaturated fatty acids having oleic acid (C18: 1), in addition to the monounsaturated fatty acids and polyunsaturated fatty acids which are frequently present. Dimeric acid ("C36di") is produced in substantial quantities in the dimerization reaction. The final product used to prepare the complex esters of the present invention is generally a mixture of dimers and trimers, usually with a dimer / trimer ratio of about 80/20. This mixture contains aliphatic structures and cyclic structures including both naphthenic and aromatic structures. If desired, dimers and / or trimers of high purity (e.g., greater than 95%) can be prepared by molecular distillation of a mixture of dimers and trimers as described above. Such a mixture of dimer and trimer as well as purified dimer and / or trimer may also be used as dimerized and / or trimerized fatty acid component. If desired, the dimerization and / or trimerized fatty acid (s) used can be hydrogenated prior to use in preparing the complex ester.

Suitably, the multifunctional carboxylic acid is not dimerized and / or trimerized acid alone, which has been found to be capable of affecting, for example, the oxidation characteristics of gear oil formulations. The maximum level of dimerization and / or trimolinic acid is 80% by weight based on the total amount of polyfunctional carboxylic acid, which still achieves acceptable oxidative stability. However, the best results are obtained when the dimerizing and / or trimerizing acid does not exceed 50 wt%, more preferably 35 wt%, of the total amount of the polyfunctional carboxylic acid.

The chain terminator is optionally used to react with a reactive OH or COOH group that may remain unreacted after reaction between the polyfunctional alcohol and the polyfunctional carboxylic acid. It is desirable that the chain terminator has a relatively long carbon chain to achieve optimal viscosity characteristics (i.e., a kinematic viscosity at 100 ° C of 30 cSt or more). In applications where oxidative stability is critical, such as gear oil formulations, the chain terminator should be saturated to be desirable. In applications where oxidative stability is less important, such as in the case of hydraulic fluids, unsaturated fatty acid-like olefins (industrial grade oleic acid) or unsaturated alcohols may be used. Of the chain terminators described above, isostearic acid (isoC18) is even more preferred. However, other fatty acid-like palmitic acids (C16) or stearic acid (C18) are also useful. Monocarboxylic acids such as octanoic acid and decanoic acid can also be used. Guerbet acid is also included in suitable monocarboxylic acids. Examples of suitable monofunctional alcohols are tetradecanol, isotetradecanol, octadecanol and isooctadecanol. Gerbet alcohols are also included in suitable monohydric alcohols.

The complex ester according to the present invention should have a kinematic viscosity at 100 DEG C of 30 to 1000 cSt, preferably 30 to 200 cSt. For certain applications, such as gear oils, a value of 100 to 140 cSt at 100 < 0 > C is preferred. The suitable kinematic viscosity of the complex ester at 40 캜 is 230 to 20,000 cSt, more suitably 230 to 2800 cSt.

The polyol, polyfunctional carboxylic acid (s) and chain terminator which react and form the complex ester are preferably used in the following amounts depending on the specific materials used ("pbw" is by weight):

15 to 20 parts by weight of a polyol, 20 to 25 parts by weight of a polyfunctional carboxylic acid and 55 to 65 parts by weight of a chain terminator.

These materials are selected so that the complex ester has a kinematic viscosity at 100 DEG C of 100 to 140 cSt.

The complex esters according to the invention are preferably used together with an extreme pressure additive (EP) and / or an antiwear additive (AW) (hereinafter EP / AW) containing a sulfur- and / , Gear oil can be used.

Thus, another embodiment of the present invention is directed to a composition comprising a complex ester as described in accordance with an embodiment of the present invention, and a sulfur- and / or phosphorus-containing EP / AW additive package, Is from 1: 3 to 9: 1). In particular, it is well known in the art to use sulfur- and / or phosphorus-containing EP / AW additive packages suitable for gear oils to avoid wear of gear wheels. Commercially available sulfur-phosphorus-containing EP-AW additive packages include, for example, Ethyl Corporation, Lubrizol and Paramins.

The complex esters according to the invention can be used as functional fluids in a variety of different applications, for example in lubricating formulations. Such esters can be used as functional fluids or additives in functional fluid compositions and / or as substrate fluids and / or thickeners.

Accordingly, the present invention also relates to the use of the complex esters described in accordance with one embodiment of the present invention as a functional fluid.

The present invention also relates to a functional fluid composition comprising a complex ester as described in accordance with an embodiment of the present invention.

The present invention also relates to the use of formulations containing complex esters as described in an embodiment of the present invention in functional fluid compositions such as transmission fluids such as automotive and industrial gear oils, axle oils and automotive transmission fluids, Oil for four-stroke engine, fuel additive, compressor oil, grease, use in chain oil, and metal working and metal rolling applications.

Examples of functional fluids and functional fluid compositions include transmission fluids such as automotive and industrial gear oils, axle oils and automotive transmission fluids and also hydraulic fluids, four-stroke engine oils, fuel additives, compressor oils, greases, chain oils and metals And those used for processing and metal rolling applications.

The complex esters according to the invention have been found to be particularly suitable for use as high viscosity base fluids and / or thickeners in general purpose oil formulations.

General purpose oil formulations comprising synthetic thickeners are known in the art. Typical synthetic thickeners include polyisobutylene (PIB), VI (viscosity index) improvers such as poly (methyl) methacrylate, olefin copolymers and polyalphaolefins (PAO) having high kinematic viscosity. An example of a PAO thickener is PAO 100, a PAO having a kinematic viscosity at 100 ° C of about 100 cSt. These high viscosity PAOs are used to achieve general characteristics and desired viscosity while maintaining thermal and oxidative stability. In addition to these PAOs, low viscosity esters are used to improve the solubility and compatibility of commonly used additives to improve thermal stability and oxidation stability and impart desired low temperature viscosity to gear oil formulations. The EP / AW additive package is used to avoid wear on the gearwheel. Finally, mineral oils with a low viscosity (i.e. kinematic viscosity at 100 ° C of 4 to 10 cSt) and also with a high viscosity index (VI), also denoted PAO 4 to PAO 10, generally exist as a base fluid . If a fully synthetic gear oil is desired, use a low viscosity PAO.

However, existing conventional synthetic gear oils containing synthetic thickeners satisfactorily function in many demanding applications, but to cope with the increasing requirements of modern gear oils such as large commercial vehicles and passenger cars or safety systems with long service intervals There is still need for improvement. It is an object of the present invention to provide a universal gear oil blend which, in particular, exhibits improved performance in gearboxes for large commercial vehicles and, if desired, may be fully synthetic.

It has been found that this object can be realized by using the complex ester as described above as a thickener.

Thus, the present invention also provides

(a) 5 to 45 parts by weight of a composite ester as described above as a thickener,

(b) 5 to 45 parts by weight of an ester having a kinematic viscosity at 100 DEG C of 2 to 10 cSt,

(c) 5 to 60 parts by weight of a mineral oil having a VI of 90 or more and / or a polyalphaolefin having a kinematic viscosity at 100 DEG C of 4 to 10 cSt, and

(d) 5 to 15 parts by weight of a common gear oil additive wherein the sum of components (a) to (d) is 100 parts by weight.

The components (b), (c) and (d) can be esters, mineral oils and / or polyalphaolefins and additives already known or useful in general gear oil formulations.

Low viscosity esters, which are component (b), may be suitable esters to improve additive stability and compatibility, improve thermal stability and oxidation stability, and impart desired low temperature viscosity to gear oil formulations. Preferably, component (b) is an ester of neopentylpolyol, preferably trimethylolpropane, with at least one aliphatic saturated monocarboxylic acid having from 6 to 12 carbon atoms. As an example of such an ester, the trade name PRIOLUBE 3970 is commercially available.

Component (c) may be mineral oil or PAO where VI should be greater than or equal to 90. However, it is preferable to use PAO, especially PAO 6 and PAO 8.

Component (d) can be an available gear oil EP / AW additive package known to be useful in automotive and industrial gear oil formulations.

The complex esters can be prepared in a batch or continuous manner. The present invention also includes reacting at least one polyfunctional alcohol, at least one polyfunctional carboxylic acid, and a chain terminator,

(a) the polyfunctional alcohol is a hindered or non-hindered aliphatic polyol,

(b) the polyfunctional carboxylic acid comprises an aliphatic dicarboxylic acid having 9 to 18 carbon atoms, a dimerization and / or a trimerized fatty acid or a mixture thereof, provided that the dimerized and trimerized fatty acid is a polyfunctional carboxylic acid Does not exceed 80 wt%, preferably does not exceed 50 wt% of the total amount used,

(c) the chain terminator is selected from the group consisting of linear saturated acids having 7 to 22, preferably 7 to 14, linear saturated hydrocarbons having 7 to 24 carbon atoms, straight chain or branched unsaturated acids having 16 to 24 carbon atoms, Or mixtures thereof, or one or more aliphatic linear or branched, saturated or unsaturated monofunctional alcohols having 14 or more carbon atoms and preferably no more than 24 carbon atoms,

(d) the complex ester has a kinematic viscosity at 100 DEG C of 30 to 1000 cSt, preferably 30 to 200 cSt.

The general additive according to one embodiment of the present invention may be blended with various additives other than the above in order to ensure a balanced performance as lubricating oil. In particular, it is preferable to contain a metal-based cleaner, an ashless dispersant, and an abrasion preventing agent in order to ensure excellent cleanliness, sludge dispersibility and abrasion resistance.

As the metallic detergent, it is preferable to use at least one alkaline earth metal detergent selected from alkaline earth metal sulfonate, alkaline earth metal phenate and alkaline earth metal salicylate.

The alkaline earth metal sulfonate is preferably an alkaline earth metal salt of an alkyl aromatic sulfonic acid having a molecular weight of 300 to 1,500, particularly preferably 400 to 700, particularly a magnesium salt and / or a calcium salt, and a calcium salt is preferably used.

As the alkaline earth metal phenate, alkaline earth metal salts of Mannich reaction of an alkylphenol, alkylphenol sulfide, alkylphenol having a linear or branched alkyl group having 4 to 30 carbon atoms, preferably 6 to 18 carbon atoms, especially a magnesium salt and / or Calcium salts are preferably used.

As the alkaline earth metal salicylate, an alkaline earth metal salt of an alkyl salicylic acid having a straight chain or branched alkyl group of 1 to 30 carbon atoms, preferably 6 to 18 carbon atoms, particularly preferably a magnesium salt and / or a calcium salt is preferably used .

The content of the metal-based cleaner is arbitrary, but it is preferably 0.05 to 0.22 mass%, preferably 0.1 to 0.2 mass%, based on the total mass of the fuel economy-saving engine oil composition.

Examples of the ashless dispersant include alkenyl succinic acid imides derived from polyolefins, alkyl succinic acid imides, and derivatives thereof. Representative succinic acid imides are prepared by reaction of a high molecular weight alkenyl group or succinic anhydride substituted with an alkyl group with a polyalkylene polyamine containing on average 4 to 10, more preferably 5 to 7, nitrogen atoms per molecule Can be obtained. Particularly, polyisobutene having a number average molecular weight of 700 to 5000, particularly polybutenyl succinic acid imide having a polyisobutene having a number average molecular weight of 900 to 3000, is more preferable as the alkenyl group or alkyl group having a high molecular weight.

This polybutenyl succinimide is obtained from polybutene obtained by polymerizing a mixture of high-purity isobutene or 1-butene with isobutene with a boron fluoride-based catalyst or an aluminum chloride-based catalyst, and the polybutenyl succinic acid imide having a vinylidene structure at the terminal of polybutene And usually 5 to 100 mol%. The polyalkylene polyamine chain preferably contains 2 to 5, especially 3 to 4, nitrogen atoms from the viewpoint of obtaining a good sludge inhibiting effect.

Examples of derivatives of polybutenyl succinic acid imides include those obtained by reacting the polybutenyl succinic acid imide with a boron compound such as boric acid or an oxygen-containing organic compound such as an alcohol, an aldehyde, a ketone, an alkylphenol, a cyclic carbonate, , So-called modified succinimide in which some or all of the remaining amino group and / or imino group is neutralized or amidated. Particularly, the boron-containing alkenyl (or alkyl) succinic acid imide obtained by the reaction with a boron compound such as boric acid is excellent in heat and oxidation stability.

The content of the ashless dispersant is arbitrary, and is preferably 0.5 to 15% by mass based on the total mass of the fuel economy-saving engine oil composition.

The fuel economy engine oil composition of the present invention preferably contains zinc dithiophosphate (ZnDTP) as an abrasion preventing agent in an amount of 0.01 to 0.10 mass% based on the total mass of the engine oil composition, preferably 0.05 to 0.08 mass% % By mass is more preferable. If the mass of the phosphorus element contained in the ZnDTP relative to the total mass of the engine oil is less than 0.01 mass%, sufficient wear prevention performance can not be obtained. If the mass of the phosphor element exceeds 0.10 mass%, the effect of poisoning on the exhaust gas purification catalyst of automobiles increases.

The ZnDTP is preferably a linear or branched alkyl group having 1 to 24 carbon atoms, a linear or branched alkenyl group having 3 to 24 carbon atoms, a linear or branched alkylcycloalkyl group having 6 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, Or compounds having branched alkylaryl groups are preferred. The alkyl group and the alkenyl group may be any of primary, secondary and tertiary.

Specific examples of zinc dithiophosphate include zinc dipropyldithiophosphate, zinc dibutyldithiophosphate, zinc dipentyldithiophosphate, zinc dihexyldithiophosphate, zinc diisopentyldithiophosphate, diethylhexyldithiophosphate Zinc, zinc dioctyldithiophosphate, zinc dinonyldithiophosphate, zinc didecyldithiophosphate, zinc didodecyldithiophosphate, zinc dipropylphenyldithiophosphate, zinc dipentylphenyldithiophosphate, dipropylmethylphenyldithi Zinc octylphosphate, zinc octophosphate, zinc dinonylphenyldithiophosphate, zinc undecylphenyldithiophosphate, and zinc undecylphenyldithiophosphate.

The content of ZnDTP is preferably 0.01 to 0.10 mass%, more preferably 0.03 to 0.08 mass%, based on the total weight of the engine oil, in terms of the weight of phosphorus (P) metal element contained in ZnDTP.

To the engine oil of the present invention, additives such as antioxidants, viscosity index improvers, pour point depressants, metal deactivators, rust inhibitors and antifoaming agents may be further added as desired.

<Examples>

As the base oil, a mineral oil base oil (kinematic viscosity: 17.7 mm 2 / s (40 ° C), 4.1 mm 2 / s (100 ° C), viscosity index: 134,% CP : 85, pour point: -20 캜) was used.

(BTA), an epoxy compound, a viscosity index improver (VI) and other additives widely added to a lubricating oil as a corrosion inhibitor are added to the base oil at a ratio shown in Table 1 To prepare an engine oil. Further, the other additives were added in the same addition amounts in common as an additive mixture comprising zinc alkyldithiophosphate (ZnDTP), Ca sulfonate, alkenyl succinic acid imide, pour point depressant and antifoaming agent. The viscosity index improver was added in such a manner that the composition had a kinematic viscosity at 100 DEG C of 9.3 to 9.5 mm &lt; 2 &gt; / s (corresponding to 30 of the SAE engine oil viscosity classification) for the entirety.

As MoDTC, R1 to R4 are mixtures of 2-ethylhexyl group and isotridecyl group, and the ratio of oxygen atom to sulfur atom is 1/1.

As the benzotriazole derivative, N, N-bis [(2-ethylhexyl) aminomethyl] -1H-benzotriazole (Irgamet 39, manufactured by Ciba Specialty Chemicals) was used.

The compounds were esterified as shown in [Table 1] to [Table 5] below to prepare a complex ester.

Ester A Ester B Trimethylolpropane 19 parts by weight Trimethylolpropane 18 parts by weight Dodecanedioic acid 22 parts by weight Decanedioic acid 18 parts by weight 59 parts by weight of isostearic acid Dimer acid 6 parts by weight Isostearic acid 58 parts by weight Ester A has a kinematic viscosity at 100 ° C of 117.0 cSt and a kinematic viscosity at 40 ° C of 1360 cSt. Ester B has a kinematic viscosity at 100 占 폚 of 121.6 cSt and a kinematic viscosity at 40 占 폚 of 1445 cSt.

Ester D Ester E Pentaerythritol 13 parts by weight Pentaerythritol 13 parts by weight Decanedioic acid 9 parts by weight Dodecanedioic acid 14 parts by weight 78 parts by weight of isostearic acid Isostearic acid 73 parts by weight Ester D has a kinematic viscosity at 100 ° C of 54.0 cSt and a kinematic viscosity at 40 ° C of 471 cSt. Ester E has a kinematic viscosity at 100 占 폚 of 93.5 cSt and a kinematic viscosity at 40 占 폚 of 1105 cSt.

Ester F Ester G Neopentyl glycol 32 parts by weight Dipropylene glycol 35 parts by weight Decanedioic acid 48 parts by weight Dodecanedioic acid 38 parts by weight Octanoic acid 11 parts by weight Octanoic acid 15 parts by weight Decanoic acid 9 parts by weight Decanoic acid 12 parts by weight The ester F has a kinematic viscosity at 100 캜 of 45.4 cSt and a kinematic viscosity at 40 캜 of 402 cSt. Ester G has a kinematic viscosity at 100 占 폚 of 31.8 cSt and a kinematic viscosity at 40 占 폚 of 231 cSt.

Esters F and G have a large number of ester groups and have specific polarities, which in particular exhibit excellent lubricity over non-polar base fluids such as mineral oils and / or synthetic hydrocarbons and / or less polar esters. Thus, esters such as ester F and ester G are suitable for use as additives in engine oil and / or as base fluid components to reduce the internal friction of the engine.

Ester H Pentaerythritol 26 parts by weight Hexanedioic acid 23 parts by weight 51 parts by weight of hexanoic acid Ester H has a kinematic viscosity at 100 占 폚 of 217 cSt and a kinematic viscosity at 40 占 폚 of 3265 cSt.

Since ester H has a very large amount of ester groups, the affinity to metal surfaces is very high. Accordingly, such esters are suitable for improving the metalworking process by improving the lubricity of the formulations by using them as base fluid components and / or additives in metal working oils.

Ester I Dipentaerythritol 23 parts by weight Hexanedioic acid 8 parts by weight Octanoic acid 38 parts by weight Decanoic acid 31 parts by weight Ester I has a kinematic viscosity at 100 캜 of 35.5 cSt and a kinematic viscosity at 40 캜 of 329 cSt.

Such esters are suitable for use as base fluid components and / or as additives for compressor oils and metal rolling oils, because of the presence of polar ester groups and high oxidation stability and good lubricity.

As the viscosity index improver, a polymethacrylate compound was used.

Each of the above engine oils was subjected to a corrosion oxidation stability test, and the oil after the test was subjected to elemental analysis by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The corrosion oxidation stability test was carried out in accordance with JIS K2503. The test conditions were a test temperature of 135 占 폚 and a test piece of copper (Cu), lead (Pb) and tin (Sn).

In addition, the fuel economy of the disclosed engine oil was evaluated by the SRV friction test (test condition: load 400 N, amplitude 1.5 mm, frequency 50 Hz, temperature 100 ° C).

It can be seen that the engine oil composition of the above example exhibits good fuel economy and is less in the elution of Cu, Pb and Sn in the corrosion oxidation stability test. Therefore, it is possible to exhibit high fuel economy saving while having excellent anti-corrosive property.

Although the present invention has been described in detail by way of preferred embodiments thereof, other forms of embodiment are possible. Therefore, the technical idea and scope of the claims set forth below are not limited to the preferred embodiments.

Claims (5)

A lubricant additive added to a lubricant base oil to form a lubricant,
Based on the lubricating oil, an organic molybdenum compound containing 0.02% by mass or more of molybdenum (Mo) and 0.5% by mass of a complex ester,
The complex ester is obtained through an esterification reaction between one or more polyfunctional alcohols and at least one polyfunctional carboxylic acid and a chain terminator,
(a) the polyfunctional alcohol is a hindered or non-hindered aliphatic polyol,
(b) the polyfunctional carboxylic acid comprises an aliphatic dicarboxylic acid having 9 to 18 carbon atoms, a dimerization and / or a trimerized fatty acid or a mixture thereof, provided that the dimerized and trimerized fatty acid is a polyfunctional carboxylic acid Not exceeding 80% by weight of the total amount used,
(c) the chain terminator is selected from the group consisting of straight chain saturated acids having 7 to 22 carbon atoms, branched saturated acids having 7 to 24 carbon atoms, straight chain or branched unsaturated acids having 16 to 24 carbon atoms, and mixtures thereof. Carboxylic acid, or at least one aliphatic linear or branched saturated or unsaturated monofunctional alcohol having 14 or more carbon atoms,
(d) the resulting composite ester has a kinematic viscosity at 100 DEG C of 30 to 1000 cSt. The method according to claim 1,
Wherein the polyfunctional alcohol is neopentylpolyol. The method according to claim 1,
A synthetic lubricant additive wherein the polyfunctional alcohol is trimethylol propane or pentaerythritol. 4. The method according to any one of claims 1 to 3,
Wherein the organic molybdenum compound is molybdenum dithiocarbamate (MoDTC). CLAIMS What is claimed is: 1. A method for producing a lubricating oil additive which is added to a lubricating oil base oil to form a lubricating oil,
Based on the lubricating oil, an organic molybdenum compound containing 0.02% by mass or more of molybdenum (Mo) and 0.5% by mass of a complex ester,
At least one multifunctional alcohol, at least one multifunctional carboxylic acid, and a chain terminator,
(a) the polyfunctional alcohol is a hindered or non-hindered aliphatic polyol,
(b) the polyfunctional carboxylic acid comprises an aliphatic dicarboxylic acid having 9 to 18 carbon atoms, a dimerization and / or a trimerized fatty acid or a mixture thereof, provided that the dimerized and trimerized fatty acid is a polyfunctional carboxylic acid Does not exceed 50% by weight of the total amount used,
(c) the chain terminator is selected from the group consisting of straight chain saturated acids having 7 to 14 carbon atoms, branched saturated acids having 7 to 24 carbon atoms, straight chain or branched unsaturated acids having 16 to 24 carbon atoms, and mixtures thereof. Or at least one aliphatic straight chain or branched saturated or unsaturated monofunctional alcohol having 14 or more carbon atoms and not exceeding 24 carbon atoms,
(d) the composite ester has a kinematic viscosity at 100 DEG C of 0 to 200 cSt.