JP2011168648A - Lubricating oil composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lubricating oil composition having good corrosion protection, a low friction coefficient, and excellent energy saving performance, in the whole industrial lubricating oil using a higher-purity base oil, and especially in machine oils, turbine oils, compressor oils, hydraulic operating oils, gear oils and bearing oils. <P>SOLUTION: This lubricating oil composition includes: a base oil comprising a mineral oil and a synthetic oil; a succinic acid derivative as an additive; and an alkanolamine compound. The resultant lubricating oil composition is suitable for the industrial lubricating oil having excellent corrosion protection, a reduced friction coefficient, and excellent energy saving performance. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a lubricating oil composition and relates to industrial lubricating oil in general using a refined base oil, and is used in particular as machine oil, hydraulic fluid, turbine oil, compressor oil, gear oil, and bearing oil. The present invention relates to a lubricating oil composition.

Lubricating oil compositions, especially industrial lubricating oil compositions, are required to have good rust prevention and friction properties, and have a low coefficient of friction (μ), which effectively reduces friction loss in machinery and equipment. However, it is required to achieve high energy saving.
For example, hydraulic equipment is frequently used in construction machinery, etc., but if the friction coefficient of lubricating oil used as hydraulic fluid is high, a micro stick-slip phenomenon occurs in the sliding part of the reciprocating packing of the hydraulic cylinder. In addition, the cylinder chattering, vibration, squealing, abnormal noise generation, and the like occur, and the hydraulic device cannot be controlled with high precision (Patent Document 1). Therefore, in order for the hydraulic cylinder to move accurately and smoothly, it is necessary to reduce the friction coefficient of the lubricating oil.

  In order to maintain the performance of the lubricating oil used in machinery and equipment, rust prevention is essential. This is because the temperature of the lubricating oil in the tank of the mechanical device fluctuates depending on the use conditions, so that condensed water may be mixed in the lubricating oil in the tank, and water is mixed in due to water leakage from the cooling water piping. This is due to the fact that

Japanese Patent Laid-Open No. 9-111277

  The present invention seeks to obtain an industrial oil lubricant having a high energy-saving property by reducing the friction coefficient exhibited by the lubricant. In addition, when such a lubricating oil composition is used as a hydraulic fluid in a hydraulic device, the hydraulic device can be controlled with high accuracy without causing phenomena such as chatter, vibration, squeal, abnormal noise, etc. of the hydraulic cylinder. At the same time, it is intended to suppress the generation of rust and to give good rust prevention properties. Thus, it is an object of the present invention to obtain a lubricating oil composition that has good rust prevention properties, low friction, high energy saving, and good operating efficiency.

  The present invention is a hydraulic operation that is rich in rust prevention and energy saving by adding a succinic acid derivative and an alkanolamine compound as additives to base oils such as mineral oil, synthetic oil, and mixed oils thereof. An industrial lubricating oil composition suitable for oil and the like can be obtained.

  ADVANTAGE OF THE INVENTION According to this invention, the friction loss which generate | occur | produces with various industrial apparatuses can be reduced effectively, and energy saving can be achieved. Further, when used as a hydraulic fluid, by reducing the friction coefficient, it is possible to accurately control the hydraulic device without causing phenomena such as chatter, vibration, squealing, and abnormal noise generation of the hydraulic cylinder. Furthermore, the generation of rust can be suppressed, and a lubricating oil composition rich in rust prevention can be obtained.

  As the base oil of the present lubricating oil composition, mineral oils and synthetic oils used in ordinary lubricating oils can be used, and in particular, group 1 and group in the API (American Petroleum Institute, American Petroleum Institute) base oil category. Base oils belonging to Group 2, Group 3, Group 4, etc. can be used alone or as a mixture.

For Group 1 base oils, for example, paraffin obtained by applying a suitable combination of solvent refining, hydrotreating, dewaxing, etc., to a lubricating oil fraction obtained by atmospheric distillation of crude oil There are mineral oils. The viscosity index is 80 to 120, preferably 95 to 110. The kinematic viscosity at 40 ° C. is preferably ² to 680 mm ² / s, more preferably 8 to 220 mm ² / s. The total nitrogen content is less than 50 ppm, preferably less than 25 ppm. Further, an aniline point of 80 to 150 ° C., preferably 90 to 120 ° C. is used.

For Group 2 base oils, for example, paraffinic mineral oil obtained by appropriately combining refining means such as hydrocracking and dewaxing for lubricating oil fractions obtained by atmospheric distillation of crude oil There is. Group 2 base oils refined by hydrorefining methods such as the Gulf Company method have a total sulfur content of less than 10 ppm and an aroma content of 5% or less, which is suitable for the present invention. The viscosity of these base oils is not particularly limited, but the viscosity index is 90 to 125, preferably 100 to 120. The kinematic viscosity at 40 ° C. is preferably ² to 680 mm ² / s, more preferably 8 to 220 mm ² / s. The total sulfur content is less than 700 ppm, preferably less than 100 ppm, more preferably less than 10 ppm. The total nitrogen content is also less than 10 ppm, preferably less than 1 ppm. Furthermore, the aniline point should be 80 to 150 ° C, preferably 100 to 135 ° C.

Group 3 base oil and Group 2 plus base oil include, for example, a paraffinic mineral oil produced by advanced hydrorefining and a dewaxing process for a lubricating oil fraction obtained by atmospheric distillation of crude oil. A base oil refined by the ISODEWAX process for converting and dewaxing the produced wax to isoparaffin, and a base oil refined by the mobile WAX isomerization process are also suitable. The viscosity of these base oils is not particularly limited, but the viscosity index is 95 to 145, preferably 100 to 140. The kinematic viscosity at 40 ° C. is preferably ² to 680 mm ² / s, more preferably 8 to 220 mm ² / s. The total sulfur content is 0 to 100 ppm, preferably less than 10 ppm. The total nitrogen content is also less than 10 ppm, preferably less than 1 ppm. Furthermore, it is good to use an aniline point of 80-150 degreeC, Preferably it is 110-135 degreeC.

  Examples of the synthetic oil include polyolefin, alkylbenzene, alkylnaphthalene, ester, polyoxyalkylene glycol, polyphenyl ether, dialkyldiphenyl ether, fluorine-containing compounds (perfluoropolyether, fluorinated polyolefin, etc.), silicone oil and the like.

The polyolefin includes polymers of various olefins or hydrides thereof. Any olefin may be used, and examples thereof include ethylene, propylene, butene, and α-olefins having 5 or more carbon atoms. In the production of polyolefin, one of the above olefins may be used alone, or two or more may be used in combination. Particularly preferred are polyolefins called polyalphaolefins (PAO), which are Group 4 base oils.
The viscosity of these synthetic base oils is not particularly limited, but the kinematic viscosity at 40 ° C. is preferably ² to 680 mm ² / s, more preferably 8 to 220 mm ² / s.

GTL (Gas Liquid) synthesized by the Fischer-Tropsch method, which is a natural gas liquid fuel technology, has an extremely low sulfur content and aromatic content compared to mineral oil base oil refined from crude oil. Is extremely high, so that it has excellent oxidation stability and very low evaporation loss, and is therefore suitable as the base oil of the present invention. The viscosity property of the GTL base oil is not particularly limited, but usually the viscosity index is 130 to 180, more preferably 140 to 175. Moreover, kinematic viscosity in 40 degreeC is 2-680 mm < ² > / s, More preferably, it is 5-120 mm < ² > / s. In general, the total sulfur content is less than 10 ppm and the total nitrogen content is less than 1 ppm. An example of such a GTL base oil product is SHELL XHVI®.

  The content of the base oil in the lubricating oil composition of the present invention is not particularly limited, but is 60% by mass or more, preferably 80% by mass or more, more preferably 90% by mass or more, and still more preferably based on the total amount of the lubricating oil composition. Is 95% by mass or more.

The succinic acid derivative is represented by the general formula 1.

In the general formula 1, X ₁ and X ₂ are each hydrogen or 3 to 6 identical or different alkyl group, alkenyl group or hydroxyalkyl group, preferably a hydrogen atom, 1-hydroxypropyl group, 2-hydroxy A propyl group, a 2-methylpropyl group, and a tertiary butyl group are preferable. X ₃ is an alkyl group or alkenyl group having 1 to 30 carbon atoms, an alkyl group having an ether bond, or a hydroxyalkyl group. For example, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, nonyl, decyl, undecyl, dodecyl, dodecylene, tridecyl, tetradecyl group, tetradecylene, pentadecyl, hexadecyl, heptadecyl, octadecyl, octadecylene, eicosyl group, docosyl group, an alkoxycarbonyl propyl, _{3- (C} 6 ~C ₁₈₎ hydrocarbonoxy _(C 3 _{~C 6)} alkyl Group, more preferably tetraisopropyl group, oleyl group, cyclohexyloxypropyl group, 3-octyloxypropyl group, 3-isooctyloxypropyl group, 3-decyloxypropyl group, 3-isodecyloxypropyl group, 3- _(C 12 ~C ₁₆₎ Arco Shipuropiru group is good. Aminated products of these compounds may also be used.

  The succinic acid derivative has an acid value defined by JIS K2501 of 10 to 300 mgKOH / g, preferably 30 to 200 mgKOH / g. The succinic acid derivative is about 0.001 to 0.5% by mass, preferably about 0.001 to 0.1% by mass, more preferably about 0.005 to 0.1% by mass in the lubricating oil composition. Used in degree. This succinic acid derivative can be used alone or in combination.

  Examples of the alkanolamine compound in the present invention include a monoalkanolamine or dialkanolamine compound represented by the general formula 2.

In the above general formula 2, one of X ₄ , X ₅ and X ₆ is hydrogen, one of them is an alkyl group or an alkenyl group, and the other is a hydroxyalkyl group, that is, two monoalcohols. Examples of the secondary amines include N-nonyl monoethanolamine, N-decyl monoethanolamine, N-undecyl monoethanolamine, N-lauryl monoethanolamine, N-tridecyl monoethanolamine, and N-myristyl monoethanolamine. N-pentadecyl monoethanolamine, N-palmityl monoethanolamine, N-heptadecyl monoethanolamine, N-oleyl monoethanolamine, N-stearyl monoethanolamine, N-isostearyl monoethanolamine, N-nona Decyl monoethanolamine, N- Icosyl monoethanolamine, N- coconut monoethanolamine, N- tallow monoethanolamine, N- hydrogenated tallow monoethanolamine, N- soybean monoethanolamine, ethanol amines and the like.

  Moreover, N-nonyl monopropanolamine, N-decyl monopropanolamine, N-undecyl monopropanolamine, N-lauryl monopropanolamine, N-tridecyl monopropanolamine, N-myristyl monopropanolamine, N-pentadecyl Monopropanolamine, N-palmitylmonopropanolamine, N-heptadecylmonopropanolamine, N-oleylmonopropanolamine, N-stearylmonopropanolamine, N-isostearylmonopropanolamine, N-nonadecylmonopropanolamine, N-eicosyl monopropanolamine, N-coconut monopropanolamine, N-tallow monopropanolamine, N-hydrogenated tallow monopropanolamine, N-soy monopropanol Min, propanol amines and the like.

Further, two of X ₄ , X ₅ and X ₆ are alkyl groups or alkenyl groups and the other is a hydroxyalkyl group, that is, tertiary amines of alcohols which are monoalkanolamines of the tertiary amine type. For example, N-dinonylethanolamine, N-didecylethanolamine, N-diundecylethanolamine, N-dilaurylethanolamine, N-ditridecylethanolamine, N-dimyristylethanolamine, N-dithiol Pentadecylethanolamine, N-dipalmitylethanolamine, N-diheptadecylethanolamine, N-dioleylethanolamine, N-distearylethanolamine, N-diisostearylethanolamine, N-dinonadecylethanolamine , N-diecosilje Noruamin, N- di coconut ethanolamine, N- di tallow ethanolamine, N- di hydrogenated tallow ethanolamine, N- di soybean ethanol amines include ethanolamine and the like.

  Also, N-dinonylpropanolamine, N-didecylpropanolamine, N-diundecylpropanolamine, N-dilaurylpropanolamine, N-ditridecylpropanolamine, N-dimyristylpropanolamine, N-dipentadecylpropanol Amine, N-dipalmitylpropanolamine, N-diheptadecylpropanolamine, N-dioleylpropanolamine, N-distearylpropanolamine, N-diisostearylpropanolamine, N-dinonadecylpropanolamine, N- Examples include propanolamines such as dieicosylpropanolamine, N-dicoconut propanolamine, N-di beef tallow propanolamine, N-dihydrogenated tallow propanolamine, N-di soy propanolamine, and the like. It is.

(Chemical formula 3)
_{X 7 -N- (X 8) 2} (3)

In the above general formula 3, assuming that X ₇ is an alkyl group or an alkenyl group and X ₈ is a hydroxyalkyl group, for example, N-octyldiethanolamine, N-nonyldiethanolamine, N-decyldiethanolamine, N-undecyldiethanolamine, N-lauryldiethanolamine, N-tridecyldiethanolamine, N-myristyldiethanolamine, N-pentadecyldiethanolamine, N-palmityldiethanolamine, N-heptadecyldiethanolamine, N-oleyldiethanolamine, N-stearyldiethanolamine, N-isostearyldiethanolamine, N-nonadecyl diethanolamine, N-eicosyl diethanolamine, N-coconut diethanolamine, N-tallow dietanol N-alkyldiethanolamines such as amines, N-hydrogenated beef tallow diethanolamine, N-soybean diethanolamine, N-octyldipropanolamine, N-nonyldipropanolamine, N-decyldipropanolamine, N-undecyldipropanolamine N-lauryldipropanolamine, N-tridecyldipropanolamine, N-myristyldipropanolamine, N-pentadecyldipropanolamine, N-palmityldipropanolamine, N-heptadecyldipropanolamine, N-oleyl Dipropanolamine, N-stearyl dipropanolamine, N-isostearyl dipropanolamine, N-nonadecyl dipropanolamine, N-eicosyl dipropanolamine, N-coconut dipropa There are N-alkyldipropanolamines such as noramine, N-tallow dipropanolamine, N-hydrogenated tallow dipropanolamine, N-soy dipropanolamine and the like.

  The alkanolamine compound in the lubricating oil composition is about 0.001 to 1% by mass, preferably about 0.001 to 0.8% by mass, more preferably about 0.005 to 0.5% by mass. Used. These compounds can be used alone or in combination.

  An ester of a polyhydric alcohol can be blended with the lubricating oil composition of the present invention. As the ester of this polyhydric alcohol, those conventionally used as oily agents, for example, glycerol, sorbitol, alkylene glycol, neopentyl glycol, trimethylolpropane, pentaerythritol, xylitol and the like have 1 to 1 carbon atoms. 24 partial or complete esters of saturated or unsaturated fatty acids can be used.

  As such, specifically, for example, as glycerol esters, glycerol monolaurate, glycerol monostearate, glycerol monopalmitate, glycerol monooleate, glycerol dilaurate, glycerol distearate, glycerol dipalmitate, glycerol Georate etc.

  The sorbitol esters include sorbitol monolaurate, sorbitol monopalmitate, sorbitol monostearate, sorbitol monooleate, sorbitol dilaurate, sorbitol dipalmitate, sorbitol distearate, sorbitol diolate, sorbitol tristearate, sorbitol tris Examples thereof include laurylate, sorbitol trioleate, sorbitol sesquioleate, and sorbitol tetraoleate.

  Examples of alkylene glycol esters include ethylene glycol monolaurate, ethylene glycol monostearate, ethylene glycol monooleate, ethylene glycol dilaurate, ethylene glycol distearate, ethylene glycol diolate, propylene glycol monolaurate, propylene glycol monostearate. Rate, propylene glycol monooleate, propylene glycol dilaurate, propylene glycol distearate, propylene glycol dioleate and the like.

  Examples of neopentyl glycol esters include neopentyl glycol monolaurate, neopentyl glycol monostearate, neopentyl glycol monooleate, neopentyl glycol dilaurate, neopentyl glycol distearate, neopentyl glycol dioleate, and the like. .

  Examples of the trimethylolpropane ester include trimethylolpropane monolaurate, trimethylolpropane monostearate, trimethylolpropane monooleate, trimethylolpropane dilaurate, trimethylolpropane distearate, and trimethylolpropanediolate.

Examples of the pentaerythritol ester include pentaerythritol monolaurate, pentaerythritol monostearate, pentaerythritol monooleate, pentaerythritol dilaurate, pentaerythritol distearate, pentaerythritol dioleate, dipentaerythritol monooleate, and the like.
As such a fatty acid ester of a polyhydric alcohol, a partial ester of a polyhydric alcohol and an unsaturated fatty acid is preferably used.

  These fatty acid esters of polyhydric alcohols are used in the lubricating oil composition at about 0.01 to 5% by mass, preferably about 0.05 to 2% by mass. If the amount used is outside the above range, the effect of reducing the friction coefficient may be weakened.

  In addition to the above-described components, various additives can be appropriately used as necessary in order to further improve the performance. These include antioxidants, metal deactivators, extreme pressure agents, oiliness improvers, antifoaming agents, viscosity index improvers, pour point depressants, cleaning dispersants, rust inhibitors, demulsifiers, etc. Other known lubricating oil additives can be mentioned.

  As antioxidant used in this invention, what is used for lubricating oil is practically preferable, and a phenolic antioxidant, an amine antioxidant, and a sulfur type antioxidant can be mentioned. These antioxidants can be used alone or in combination in the lubricating oil composition in the range of about 0.01 to 5% by mass.

  Examples of the amine antioxidant include p, p′-dioctyl-diphenylamine (Seiko Chemical Co., Ltd .: Nonflex OD-3), p, p′-di-α-methylbenzyl-diphenylamine, and Np-butylphenyl. Dialkyl-diphenylamines such as -Np'-octylphenylamine, monoalkyldiphenylamines such as mono-t-butyldiphenylamine and monooctyldiphenylamine, di (2,4-diethylphenyl) amine, di (2-ethyl- Bis (dialkylphenyl) amines such as 4-nonylphenyl) amine, alkylphenyl-1-naphthylamines such as octylphenyl-1-naphthylamine, Nt-dodecylphenyl-1-naphthylamine, 1-naphthylamine, phenyl-1 -Naphthylamine, phenyl Aryl-naphthylamines such as 2-naphthylamine, N-hexylphenyl-2-naphthylamine, N-octylphenyl-2-naphthylamine, N, N′-diisopropyl-p-phenylenediamine, N, N′-diphenyl-p-phenylene Examples include phenylenediamines such as diamine, phenothiazines (manufactured by Hodogaya Chemical Co., Ltd .: Phenothiazine), and phenothiazines such as 3,7-dioctylphenothiazine.

  Examples of sulfur-based antioxidants include dialkyl sulfides such as didodecyl sulfide and dioctadecyl sulfide, didodecyl thiodipropionate, dioctadecyl thiodipropionate, dimyristyl thiodipropionate, and dodecyl octadecyl thiodipropionate. Examples include thiodipropionic acid esters and 2-mercaptobenzimidazole.

Examples of phenolic antioxidants include 2-t-butylphenol, 2-t-butyl-4-methylphenol, 2-t-butyl-5-methylphenol, 2,4-di-t-butylphenol, 2,4- Dimethyl-6-t-butylphenol, 2-t-butyl-4-methoxyphenol, 3-t-butyl-4-methoxyphenol, 2,5-di-t-butylhydroquinone (manufactured by Kawaguchi Chemical Co., Ltd .: Antage DBH), 2,6-di-t-butylphenol such as 2,6-di-t-butylphenol, 2,6-di-t-butyl-4-methylphenol, 2,6-di-t-butyl-4-ethylphenol 2,6-di-t-butyl- such as -4-alkylphenols, 2,6-di-t-butyl-4-methoxyphenol, 2,6-di-t-butyl-4-ethoxyphenol - there is a alkoxy phenols.
3,5-di-t-butyl-4-hydroxybenzyl mercapto-octyl acetate, n-octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate (manufactured by Yoshitomi Pharmaceutical Co., Ltd.) Yoshinox SS), n-dodecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 2'-ethylhexyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) ) Alkyl-3- () such as propionate, benzenepropanoic acid 3,5-bis (1,1-dimethyl-ethyl) -4-hydroxy-C7-C9 side chain alkyl ester (Ciba Specialty Chemicals: Irganox L135) 3,5-di-t-butyl-4-hydroxyphenyl) propionates, 2,6-di-t-butyl-α- Methylamino-p-cresol, 2,2′-methylenebis (4-methyl-6-t-butylphenol) (manufactured by Kawaguchi Chemical Co .: Antage W-400), 2,2′-methylenebis (4-ethyl-6-t) There are 2,2′-methylenebis (4-alkyl-6-t-butylphenol) s such as (butylphenol) (manufactured by Kawaguchi Chemical Co., Ltd .: Antage W-500).

  Further, 4,4′-butylidenebis (3-methyl-6-tert-butylphenol) (manufactured by Kawaguchi Chemical Co., Ltd .: Antage W-300), 4,4′-methylenebis (2,6-di-tert-butylphenol) (shell) -Japan company make: Ionox220AH), 4,4'-bis (2,6-di-t-butylphenol), 2, 2- (di-p-hydroxyphenyl) propane (shell Japan company make: bisphenol A), 2,2-bis (3,5-di-t-butyl-4-hydroxyphenyl) propane, 4,4′-cyclohexylidenebis (2,6-t-butylphenol), hexamethylene glycol bis [3- ( 3,5-di-t-butyl-4-hydroxyphenyl) propionate] (manufactured by Ciba Specialty Chemicals: Irganox L109), Ethylene glycol bis [3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionate] (manufactured by Yoshitomi Pharmaceutical Co., Ltd .: Tominox 917), 2,2′-thio- [diethyl-3- (3 5-di-t-butyl-4-hydroxyphenyl) propionate] (manufactured by Ciba Specialty Chemicals: Irganox L115), 3,9-bis {1,1-dimethyl-2- [3- (3-t-butyl -4-hydroxy-5-methylphenyl) propionyloxy] ethyl} 2,4,8,10-tetraoxaspiro [5,5] undecane (Sumitomo Chemical: Sumilizer GA80), 4,4'-thiobis (3-methyl -6-tert-butylphenol) (manufactured by Kawaguchi Chemical Co .: Antage RC), 2,2'-thiobis (4,6-di-tert-butyl-resorcin) How bisphenols there.

  Tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane (manufactured by Ciba Specialty Chemicals: Irganox L101), 1,1,3-tris (2-methyl) -4-hydroxy-5-t-butylphenyl) butane (Yoshitomi Pharmaceutical Co., Ltd .: Yoshinox 930), 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4 -Hydroxybenzyl) benzene (manufactured by Shell Japan: Ionox 330), bis- [3,3′-bis- (4′-hydroxy-3′-t-butylphenyl) butyric acid] glycol ester, 2- (3 ', 5'-di-tert-butyl-4-hydroxyphenyl) methyl-4- (2 ", 4" -di-tert-butyl-3 "-hydroxyphenyl Polyphenols such as methyl-6-tert-butylphenol, 2,6-bis (2′-hydroxy-3′-tert-butyl-5′-methyl-benzyl) -4-methylphenol, pt-butylphenol and formaldehyde And a phenol aldehyde condensate such as a condensate of pt-butylphenol and acetaldehyde.

  Examples of phosphorus antioxidants include triaryl phosphites such as triphenyl phosphite and tricresyl phosphite, trialkyl phosphites such as trioctadecyl phosphite and tridecyl phosphite, and tridodecyl trithiophosphite. It is done.

  Metal deactivators that can be used in conjunction with the compositions of the present invention include 4-alkyl-benzotriazoles such as benzotriazole, 4-methyl-benzotriazole, 4-ethyl-benzotriazole, 5-methyl-benzotriazole, 5- 5-alkyl-benzotriazoles such as ethyl-benzotriazole, 1-alkyl-benzotriazoles such as 1-dioctylaminomethyl-2,3-benzotriazole, 1 such as 1-dioctylaminomethyl-2,3-toltriazole -2- (alkyldithio) such as benzotriazole derivatives such as alkyl-tolutriazoles, benzimidazole, 2- (octyldithio) -benzimidazole, 2- (decyldithio) -benzimidazole, 2- (dodecyldithio) -benzimidazole ) Benzimidazole derivatives such as 2- (alkyldithio) -toluimidazoles such as benzimidazoles, 2- (octyldithio) -toluimidazole, 2- (decyldithio) -toluimidazole, 2- (dodecyldithio) -toluimidazole, etc. is there.

  Indazole derivatives such as tolindazoles such as indazole, 4-alkyl-indazole, 5-alkyl-indazole, benzothiazole, 2-mercaptobenzothiazole derivative (manufactured by Chiyoda Chemical Co., Ltd .: Thiolite B-3100), 2- (hexyl) 2- (Alkyldithio) benzothiazoles such as dithio) benzothiazole, 2- (octyldithio) benzothiazole, 2- (alkyldithio) such as 2- (hexyldithio) tolthiazole, 2- (octyldithio) tolthiazole Tolthiazoles, 2- (N, N-diethyldithiocarbamyl) benzothiazole, 2- (N, N-dibutyldithiocarbamyl) -benzothiazole, 2- (N, N-dihexyldithiocarbamyl) -benzothiazole 2- (N, N-dia Kirdithiocarbamyl) benzothiazoles, 2- (N, N-diethyldithiocarbamyl) tolthiazole, 2- (N, N-dibutyldithiocarbamyl) tolthiazole, 2- (N, N-dihexyldithiocarbamyl) ) There are benzothiazole derivatives such as 2- (N, N-dialkyldithiocarbamyl) -torzothiazoles such as tolthiazole.

Furthermore, 2- (alkyldithio) -benzoxazoles such as 2- (octyldithio) benzoxazole, 2- (decyldithio) benzoxazole, 2- (dodecyldithio) benzoxazole, 2- (octyldithio) toluoxazole, 2 Benzoxazole derivatives such as 2- (alkyldithio) toluazoles such as-(decyldithio) toluxazole and 2- (dodecyldithio) toluxazole, 2,5-bis (heptyldithio) -1,3,4-thiadiazole, 2 , 5-bis (nonyldithio) -1,3,4-thiadiazole, 2,5-bis (dodecyldithio) -1,3,4-thiadiazole, 2,5-bis (octadecyldithio) -1,3,4 2,5-bis (alkyldithio) -1,3,4-thio such as thiadiazole Diazoles, 2,5-bis (N, N-diethyldithiocarbamyl) -1,3,4-thiadiazole, 2,5-bis (N, N-dibutyldithiocarbamyl) -1,3,4-thiadiazole 2,5-bis (N, N-dialkyldithiocarbamyl) -1,3,4-thiadiazoles such as 2,5-bis (N, N-dioctyldithiocarbamyl) -1,3,4-thiadiazole 2-N, N-dibutyldithiocarbamyl-5-mercapto-1,3,4-thiadiazole, 2-N, N-dioctyldithiocarbamyl-5-mercapto-1,3,4-thiadiazole Thiadiazole derivatives such as N, N-dialkyldithiocarbamyl-5-mercapto-1,3,4-thiadiazoles, 1-di-octylaminomethyl-2,4-triazol Like 1-alkyl-2,4-triazole derivative of triazoles such like.
These metal deactivators can be used alone or in combination within the range of about 0.01 to 0.5% by mass in the lubricating oil composition.

A phosphorus compound can also be added to the lubricating oil composition of the present invention, thereby further imparting wear resistance and extreme pressure. Examples of the phosphorus compound suitable for the present invention include phosphoric acid ester, acidic phosphoric acid ester, amine salt of acidic phosphoric acid ester, chlorinated phosphoric acid ester, phosphite ester, phosphorothionate, zinc dithiophosphate, and dithiophosphorus. Examples include esters of acids and alkanols or polyether alcohols or derivatives thereof, phosphorus-containing carboxylic acids, and phosphorus-containing carboxylic acid esters.
These phosphorus compounds can be used alone or in combination within the range of about 0.01 to 2% by mass in the lubricating oil composition.

  Examples of the phosphate ester include tributyl phosphate, tripentyl phosphate, trihexyl phosphate, triheptyl phosphate, trioctyl phosphate, trinonyl phosphate, tridecyl phosphate, triundecyl phosphate, tridodecyl phosphate, tritridecyl phosphate, Tetradecyl phosphate, tripentadecyl phosphate, trihexadecyl phosphate, triheptadecyl phosphate, trioctadecyl phosphate, trioleyl phosphate, triphenyl phosphate, tris (iso-propylphenyl) phosphate, triaryl phosphate, tricresyl phosphate, Trixylenyl phosphate, cresyl diphenyl phosphate, and xyl Such as sulfonyl diphenyl phosphate.

  Specific examples of the acidic phosphate ester include monobutyl acid phosphate, monopentyl acid phosphate, monohexyl acid phosphate, monoheptyl acid phosphate, monooctyl acid phosphate, monononyl acid phosphate, monodecyl acid phosphate, monoundecyl acid Phosphate, monododecyl acid phosphate, monotridecyl acid phosphate, monotetradecyl acid phosphate, monopentadecyl acid phosphate, monohexadecyl acid phosphate, monoheptadecyl acid phosphate, monooctadecyl acid phosphate, monooleyl acid phosphate, dibutyl acid Dipentyl acid phosphate Xyl acid phosphate, diheptyl acid phosphate, dioctyl acid phosphate, dinonyl acid phosphate, didecyl acid phosphate, diundecyl acid phosphate, didodecyl acid phosphate, ditridecyl acid phosphate, ditetradecyl acid phosphate, dipentadecate Examples include dihexadecyl acid phosphate, diheptadecyl acid phosphate, dioctadecyl acid phosphate, and dioleyl acid phosphate.

  Examples of the amine salt of the acidic phosphate ester include methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, heptylamine, octylamine, dimethylamine, diethylamine, dipropylamine, and dibutylamine. , Salts with amines such as dipentylamine, dihexylamine, diheptylamine, dioctylamine, trimethylamine, triethylamine, tripropylamine, tributylamine, tripentylamine, trihexylamine, triheptylamine, and trioctylamine It is done.

  Examples of the phosphites include dibutyl phosphite, dipentyl phosphite, dihexyl phosphite, diheptyl phosphite, dioctyl phosphite, dinonyl phosphite, didecyl phosphite, diundecyl phosphite, didodecyl phosphite, geode Rail phosphite, diphenyl phosphite, dicresyl phosphite, tributyl phosphite, tripentyl phosphite, trihexyl phosphite, triheptyl phosphite, trioctyl phosphite, trinonyl phosphite, tridecyl phosphite, triundecyl Examples thereof include phosphite, tridodecyl phosphite, trioleyl phosphite, triphenyl phosphite, and tricresyl phosphite.

  Specific examples of the phosphorothionate include tributyl phosphorothioate, tripentyl phosphorothioate, trihexyl phosphorothionate, triheptyl phosphorothionate, trioctyl phosphorothionate, trinonyl phosphate. Phorothionate, tridecyl phosphorothionate, triundecyl phosphorothionate, tridodecyl phosphorothionate, tritridecyl phosphorothionate, tritetradecyl phosphorothionate, tripentadecyl phosphorothionate, tri Hexadecyl phosphorothioate, triheptadecyl phosphorothionate, trioctadecyl phosphorothionate, trioleyl phosphorothionate, triphenyl phosphorothionate, tricresyl phosphorothioate , Trixylenyl phosphorothionate, cresyl diphenyl phosphorothionate, xylenyl diphenyl phosphorothionate, tris (n-propylphenyl) phosphorothionate, tris (isopropylphenyl) phosphorothionate, tris (N-Butylphenyl) phosphorothionate, Tris (isobutylphenyl) phosphorothionate, Tris (s-butylphenyl) phosphorothionate, Tris (t-butylphenyl) phosphorothionate, and the like can be given. Mixtures of these can also be used.

Examples of the zinc dithiophosphate generally include zinc dialkyldithiophosphate, zinc diaryldithiophosphate, zinc arylalkyldithiophosphate, and the like. For example, the zinc group of zinc dialkyldithiophosphate is a zinc dialkyldithiophosphate having an alkylaryl group substituted with a primary or secondary alkyl group having 3 to 22 carbon atoms or an alkyl group having 3 to 18 carbon atoms. used.
Specific examples of zinc dialkyldithiophosphate include zinc dipropyldithiophosphate, zinc dibutyldithiophosphate, zinc dipentyldithiophosphate, zinc dihexyldithiophosphate, zinc diisopentyldithiophosphate, zinc diethylhexyldithiophosphate, zinc dioctyldithiophosphate, Zinc nonyldithiophosphate, zinc didecyldithiophosphate, zinc didodecyldithiophosphate, zinc dipropylphenyldithiophosphate, zinc dipentylphenyldithiophosphate, zinc dipropylmethylphenyldithiophosphate, zinc dinonylphenyldithiophosphate, didodecylphenyldithiophosphate Zinc, zinc dodecylphenyl dithiophosphate, and the like can be mentioned.

  As the phosphorus-containing carboxylic acid compound such as phosphorus-containing carboxylic acid and ester, the structure is not particularly limited as long as both the carboxyl group and the phosphorus atom are included in the same molecule. From the viewpoint of oxidation stability, phosphorylated carboxylic acid or phosphorylated carboxylic acid ester is preferred. Examples of the phosphorylated carboxylic acid and phosphorylated carboxylic acid ester include compounds represented by the following general formula (4).

In the general formula 4, R ₁ and R ₂ may be the same or different and each represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, R ₃ represents an alkylene group having 1 to 20 carbon atoms, R ₄ represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, and X ₁₁ , X ₁₂ , X ₁₃ and X ₁₄ may be the same or different and each represents an oxygen atom or a sulfur atom.
Examples of the hydrocarbon group having 1 to 30 carbon atoms in R ₁ and R ₂ in the general formula (4) include an alkyl group, an alkenyl group, an aryl group, an alkylaryl group, and an arylalkyl group.

  Among the phosphorylated carboxylic acids, useful β-dithiophosphorylated propionic acid has a structure represented by the following general formula (5).

  Specific examples of the β-dithiophosphorylated propionic acid include 3- (di-isobutoxy-thiophosphorylsulfanyl) -2-methyl-propionic acid.

  The content of the phosphorus-containing carboxylic acid compound in the lubricating oil composition is not particularly limited, but is preferably 0.001 to 1% by mass, more preferably 0.002 to 0.00% in the lubricating oil composition. 5% by mass. If the content of the phosphorus-containing carboxylic acid compound is less than the lower limit, sufficient lubricity tends to be not obtained. On the other hand, even if it exceeds the upper limit, there is a tendency that the lubricity improvement effect corresponding to the content does not tend to be obtained, and furthermore, there is a possibility that the heat / oxidation stability and the hydrolysis stability may be lowered.

Of the phosphorylated carboxylic acids represented by the general formula (4), for the content of the compound _{R 4} is a hydrogen atom, 0.001 to 0.1 wt%, preferably from 0.002 to 0 0.08% by mass, more preferably 0.003 to 0.07% by mass, still more preferably 0.004 to 0.06% by mass, and still more preferably 0.005 to 0.05% by mass.

In order to improve low temperature fluidity and viscosity characteristics, a pour point depressant and a viscosity index improver may be added to the lubricating oil composition of the present invention.
Examples of the viscosity index improver include non-dispersed viscosity index improvers such as polymethacrylates, ethylene-propylene copolymers, styrene-diene copolymers, polyisobutylene, polystyrene and other olefin polymers, and nitrogen-containing compounds. Examples thereof include a dispersion type viscosity index improver obtained by copolymerizing monomers. The addition amount can be used in the range of about 0.05 to 20% by mass in the lubricating oil composition.
Examples of the pour point depressant include polymethacrylate polymers. The addition amount can be used in the range of about 0.01 to 5% by mass in the lubricating oil composition.

  In order to impart antifoaming properties to the lubricating oil composition of the present invention, an antifoaming agent may be added. Examples of antifoaming agents suitable for the present invention include organosilicates such as dimethylpolysiloxane, diethyl silicate and fluorosilicone, and non-silicone antifoaming agents such as polyalkyl acrylate. The addition amount can be used in the lubricating oil composition in the range of about 0.0001 to 0.1% by mass, alone or in combination.

  Demulsifiers suitable for the present invention include those commonly used as lubricating oil additives. The addition amount can be used in the range of about 0.0005 to 0.5 mass% in the lubricating oil composition.

EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated concretely, this invention is not limited only to these Examples.
In preparing Examples and Comparative Examples, the following composition materials were prepared.
1. Base oil 1 (Gp2): A paraffinic mineral oil obtained by appropriately combining refining means such as hydrocracking and dewaxing to a lubricating oil fraction obtained by atmospheric distillation of crude oil. Those classified as Group 2 by API (American Petroleum Institute) base oil classification.
(Characteristics: Kinematic viscosity at 100 ° C .; 5.35 mm ² / s, kinematic viscosity at 40 ° C .; 31.4 mm ² / s, viscosity index; 103, sulfur content (sulfur element equivalent value); less than 10 ppm, nitrogen content Content (nitrogen element conversion value): less than 1 ppm, aniline point: 110 ° C., parafun content of ring analysis by ASTM D3238 method: 62%, naphthene content; 38%, same aroma content: less than 1%, according to ASTM D5480 method (First boiling point temperature by gas chromatography: 312 ° C)
2. Base oil 2 (GTL5): GTL base oil synthesized by the Fischer-Tropsch method and classified into Group 3 by API base oil classification. [SHELL XHVI 5 (registered trademark)]
(Characteristics: Kinematic viscosity at 100 ° C .; 5.06 mm ² / s, kinematic viscosity at 40 ° C .; 23.6 mm ² / s, viscosity index; 148, sulfur content (sulfur element equivalent value); less than 10 ppm, nitrogen content Content (nitrogen element equivalent); less than 1 ppm, aniline point; density at 126 ° C. and 15 ° C .; density at 0.820 and 20 ° C .; refractive index at 0.817 and 20 ° C .; 1.456, ASTM D5480 gas chromatographic distillation The initial distillation temperature by: 365 ° C., 30% distillation temperature; 431 ° C., 50% distillation temperature; 460 ° C.)
3. Additive A: Succinic acid derivative; tetraisopropenyl succinic acid, 1,2-propanediol half ester (acid value according to JIS K2501 method: 160 mgKOH / g)
4). Additive B: N-alkenyl diethanolamine (main component is N-oleyl diethanolamine); tertiary amine compound (base number according to JIS K2501 method: 160 mgKOH / g)

(Examples 1-2, Comparative Examples 1-3)
Using the composition materials described above, lubricating oil compositions of Examples 1 and 2 and Comparative Examples 1 to 3 were prepared according to the compositions shown in Table 1.

(test)
The following tests were conducted on the lubricating oil compositions of Examples 1 and 2 and Comparative Examples 1 to 3 to see their performance.

(Coefficient of friction)
The coefficient of friction was measured with a Kamata-type pendulum type oiliness tester manufactured by Shinko Machine Co., Ltd. In this test, test oil is applied to the friction portion of the pendulum fulcrum, the pendulum is vibrated, and the friction coefficient is obtained from the vibration attenuation.
The test was evaluated according to the following criteria.
The coefficient of friction is 0.135 or less.
Coefficient of friction is less than 0.136 to 0.150 ... ○ (good)
Friction coefficient is 0.150 or more.
(The smaller the friction coefficient, the better.)

(Rust prevention test)
In accordance with JIS K2510, 300 ml of test oil is collected in a container installed in a thermostatic bath, stirred at 1000 revolutions per minute, and when the temperature reaches 60 ° C., an iron test piece is inserted into the test oil. 30 ml of artificial seawater was added and stirring was continued for 24 hours while maintaining the temperature at 60 ° C., and then the test piece was taken out and visually evaluated for the presence or absence of rust on the test piece.

(Test results)
The results of each test are shown in Table 1.

(Discussion)
As is apparent from the test results shown in Table 1, when the base oil 1 shown in Example 1 is used in combination with a succinic acid derivative (additive A) and an alkanolamine (additive B), the friction coefficient is “0.117. ”Is low and excellent (◎), and rust does not occur even in the artificial seawater of the rust prevention test, and it passes (◯).
On the other hand, only the base oil 1 of Comparative Example 1 has a very high friction coefficient of “0.307” and is poor (×), and rust is generated even in artificial seawater in the rust prevention test. Is rejected (x). When the succinic acid derivative (additive A) is added to the base oil 1 of Comparative Example 2, rust does not occur even in the artificial seawater in the rust prevention test, and it passes (O), but the friction coefficient is " “0.159”, which is high and bad (×). In addition, when the alkanolamine (additive B) is added to the base oil 1 of Comparative Example 3, the friction coefficient is excellent (（), but is “0.122”, and it is rusted in artificial seawater in the rust prevention test. Has occurred and is rejected (x), and it can be seen that excellent results are obtained in the example 1.
Moreover, the excellent result was similarly obtained also about the thing of Example 2 which changed the base oil 1 of Example 1 into the base oil 2. FIG.

Claims (5)

  A lubricating oil composition comprising a succinic acid derivative and an alkanolamine compound as additives in a base oil of mineral oil and / or synthetic oil.   The lubricating oil composition according to claim 1, wherein the acid value of the succinic acid derivative is 10 to 300 mg KOH / g (JIS K2501).   The lubricating oil composition according to claim 1 or 2, wherein the alkanolamine compound is diethanolamine.   The lubricating oil composition according to any one of claims 1 to 3, wherein the lubricating oil composition contains 0.001 to 0.5 mass% of the succinic acid derivative and 0.001 to 1 mass% of an alkanolamine compound. object.   The lubricating oil composition according to any one of claims 1 to 4, wherein the base oil is GTL.