Technical field
[0001]
　The present invention relates to a lubricating oil composition, more particularly it does not substantially contain a sulfur-containing metal complexes, oxidative stability than ever, a lubricating oil composition excellent in low sludge properties.
Background technique
[0002]
　Lubricant engine oil, drive system oil, turbine oil, hydraulic oil, are used in various applications such as grease. Also in any of its applications, for contact with peroxy radicals and peroxides which are active species of oxidative degradation produced by heat or light, excellent oxidation resistance is demanded. For these reasons, in order to prevent the oxidative degradation in the lubricating oil, it is essential to the addition of antioxidant.
　Examples of the antioxidant in lubricating oils, chain terminators such as aromatic amine compounds, phenolic compounds, such as peroxide decomposers such as sulfur compounds and molybdenum compounds are known from the prior art. Further, the performance of various antioxidants, different and use temperature range, hoping a synergistic effect has also been made to combination of two or more of those (Patent Document 1).
　Whereas antioxidants ashless such as an aromatic amine compound and the phenolic compound has a feature generation is less sludge, can not prevent the deterioration of the lubricating oil in the long term exhausted self immolative because problems was there.
　On the other hand, peroxide resolution of the sulfur-containing metal complexes such as zinc dialkyl dithiophosphate and molybdenum compounds are known to act catalytically, it is possible to prevent the long term oxidative degradation. However, these and sludge into use process, there is a problem such as causing damage to the equipment.
　Ashless sulfur compound functions as peroxide decomposers like the sulfur-containing metal complex. However, benzyl disulfide, which is a typical ashless sulfur-based antioxidant, activity was having problems such as low compared to the sulfur-containing metal complex.
CITATION
Patent Document
[0003]
Patent Document 1: Laid-Open Patent Publication No. 2010-242085
Summary of the Invention
Problems that the Invention is to Solve
[0004]
　The present invention may also be intended to provide both a combination of a conventional sulfur-based antioxidant and a chain stopping agent was not possible, superior to both oxidation life and low sludge of lubricating oil compositions it is. Especially temperature is low, it is preferably used a combustion chamber as a machine lubricating oil without lubrication.
Means for Solving the Problems
[0005]
　The present inventors have results of extensive studies, the lubricating base oil, (A) a lubricating oil composition containing a specific sulfur-containing compound [B] chain terminators, own the component [A] It quantified containing, and found that a lubricating oil composition is substantially free to achieve its purpose of sulfur-containing metal complexes, in which the present invention has been completed.
[0006]
　That is, the present invention is a lubricating oil base oil, represented by [A] [A1] cyclic sulfide ester represented by the following general formula (1) and / or (2), [A2] represented by the following general formula (3) sulfide ester is selected from the group consisting of [A3] the following general formula (4) sulfur compounds represented by, and [A4] sulfide fats derived from fat than 50 mol% is linoleic acid among total fatty acids constituting the fat or oil sulfur-containing compounds, and [B] a lubricating oil composition containing a chain terminator, is 10 to 400 ppm by weight as elemental sulfur amount in lubricating oil compositions based on the content of the component [a], and a sulfur-containing a lubricating oil composition characterized in that it is substantially free of metal complexes.
[Chemical formula 1]

(Equation (1), (R in 2) represents a hydrocarbyl group, a, b, c, d are each independently an integer of 3 or more, the sum of a and b 8 ~ 14, the sum of c and d is 7-13 and is. equation (3) R in 1 and R 2 indicate each individual hydrogen atom or a hydrocarbyl group. provided that at least one is a hydrocarbyl group .l, n, m , o is are each independently an integer of 2 or more, .x the sum of l and m is the sum of 12-20, n and o is 12 to 20 represents an integer of 1-3. equation (4) the p, q are each an individual integer of 5 or more, r is an integer of 1-3.)
[0007]
　Further, the present invention is the lubricating oil composition, characterized in that [B] chain terminator is a hindered phenol.
　Further, the present invention is the lubricating oil composition of which, wherein the sulfur content of the lubricating base oil is less than 10 mass ppm.
　Furthermore, the present invention is the lubricant composition characterized in that it is used as a machine for lubricating oil which does not lubricate the combustion chamber.
Effect of the Invention
[0008]
　The lubricating oil composition of the present invention is an excellent lubricating oil composition having both oxidation life and low sludge resistance was, in order to exert particular its effect when using temperature is low, low use temperature, lubricate the combustion chamber it is suitable as a machine lubricating oil which does not.
DESCRIPTION OF THE INVENTION
[0009]
　Below, the present invention will be described in detail.
[0010]
　The lubricating base oil of the lubricating oil composition of the present invention, mineral oils, synthetic oils and fats are used. These may be a mixture.
[0011]
　Examples of the mineral oil, the lubricating oil fractions obtained by atmospheric distillation and vacuum distillation of crude oil, solvent deasphalting, solvent extraction, hydrocracking, solvent dewaxing, catalytic dewaxing, hydrorefining, washing sulfate , paraffinic mineral oils or naphthenic mineral oil purification treatment was purified appropriately combined one or more clay treatment or the like.
[0012]
　Synthetic oils, such as propylene oligomer, polybutene, polyisobutylene, 1-octene oligomer, 1-decene oligomer, co-oligomer of ethylene and propylene, co-oligomers of ethylene and 1-octene, ethylene and 1-decene poly α- olefins (PAO), or their hydrides, such as co-oligomer; isoparaffins; monoalkyl benzene, dialkyl benzene, alkyl benzenes poly alkylbenzene; monoalkyl naphthalene, dialkyl naphthalene, alkylnaphthalene polyalkyl naphthalene; dioctyl adipate, di 2-ethylhexyl adipate, diisodecyl adipate, ditridecyl adipate, di-2-ethylhexyl sebacate, dibasic acid esters such as ditridecyl glutarate; Tribasic acid esters such as trimellitic acid; trimethylolpropane caprylate, trimethylolpropane pelargonate, trimethylolpropane oleate, pentaerythritol 2-ethylhexanoate, polyol esters such as pentaerythritol pelargonate; polyethylene glycol, polypropylene glycol , polyoxyethylene polyoxypropylene glycol, polyethylene glycol monoether, polypropylene Gree mono ether, polyoxyethylene polyoxypropylene glycol monomethyl ether, polyethylene glycol ethers, polypropylene glycol ethers, polyglycols such as polyoxyethylene polyoxypropylene glycol ether; mono alkyl diphenyl ether, dialkyl diphenyl Mentioned fluoroether such as perfluoro ethers, and the like; silicone oil; ethers, monoalkyl triphenyl ethers, dialkyl triphenyl ether, tetraphenyl ether, monoalkyl tetraphenyl ethers, dialkyl tetraphenyl ethers, phenyl ethers of penta phenyl ether is, it can be used alone or in admixture.
[0013]
　The fats and oils include beef tallow, lard, soybean oil, rapeseed oil, rice bran oil, coconut oil, palm oil, palm kernel oil, hydrogenated products thereof or a mixture of two or more thereof.
[0014]
　Sulfur content of the lubricating base oil is preferably not more than 10 mass ppm, more preferably less than 5 mass ppm, most preferably at most 1 mass ppm. By sulfur than 10 mass ppm, it is possible to further improve the oxidation stability.
　Note that the sulfur content in the present invention means a value measured by ICP.
[0015]
　Total aromatic content of the lubricating base oil is not particularly limited, from the viewpoint of oxidation stability, preferably at most 25 mass%, more preferably 15 wt% or less, 5 wt% or less and more preferably.
　Note that the total aromatic content in the present invention, Petroleum Institute method JPI-5S-49-97 the content of the wholly aromatic measured in "Petroleum products - high performance liquid chromatography - hydrocarbon type test method" means.
[0016]
　Kinematic viscosity at 40 ° C. of the lubricating base oil is not particularly limited, 1 ~ 100 mm 2 are preferred / s, 5 ~ 80 mm 2 and more preferably is / s, 10 ~ 50 mm 2 and further preferably / s. 40 ° C. kinematic viscosity 1 mm 2 reduces the lubricity and less than / s, is not preferable to deteriorate the working environment at the occurrence of mist.
　Note that the kinematic viscosity at 40 ° C. in the present invention refers to a value measured by a capillary viscometer.
[0017]
　The viscosity index of the lubricating base oil of the present invention is not particularly limited, preferably 100 or more, more preferably 110 or more, more preferably 120 or more. On the other hand, is preferably 200 or less. By a viscosity index of 100 or more, the viscosity - temperature characteristic and heat and oxidation stability, is improved volatile anti-tend coefficient of friction decreases, also tends to be improved anti-wear properties. Further, since the viscosity index is 200 or less, it tends to improve the low-temperature viscosity characteristics.
　Incidentally, a viscosity index in the present invention means a measured viscosity index in compliance with JIS K 2283.
[0018]
　The lubricating oil composition of the present invention, as (A) component, the cyclic sulfide ester represented by [A1] Formula (1) and / or (2), sulfurized ester represented by [A2] Formula (3), [A3] sulfur compound represented by the general formula (4), and [A4] one or more 50 mole% of the total fatty acids constituting the fat or oil is selected from the group consisting of sulfurized fats and oils derived from fats and oils is linoleic acid containing two or more sulfur-containing compounds.
[0019]
　[A] [A1] component in the component is a cyclic sulfide ester represented by the following general formula (1) and / or (2).
[0020]
[Formula 2]

[0021]
　R in the general formula (1) or (2) indicates a hydrocarbyl group.
　The number of carbon atoms of the hydrocarbyl group is not particularly limited, is usually 1-24, preferably 1-12, more preferably 1-6, more preferably 1-3. Examples of the hydrocarbyl group include a methyl group, an ethyl group, a propyl group, an alkyl group such as isopropyl group; a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cycloalkyl group such as cyclohexyl group; a phenyl group, cresyl group, etc. it can be exemplified aryl groups.
　Alkyl group is preferred from the viewpoint of adsorbing and oxidation stability of a lubricating surface Among these, a methyl group, an ethyl group are particularly preferred.
[0022]
　A in the general formula (1) or (2), b, c and d are each individually an integer of 3 or more, the sum of a and b in 8-14, the sum of c and d is 7-13 is there.
　It decreased solubility base oil that it is less than 8 the sum of a and b, whereas when it exceeds 14 storage stability at low temperatures decreases. The sum of c and d is solubility decreases with respect to the base oil and less than 7, whereas more than 13 when storage stability at low temperature is lowered.
[0023]
　Sulfurized ester represented by the general formula (1) or (2) can be obtained as a sulfide of a fatty acid ester having at least two unsaturated bonds to close the position of the hydrocarbon chain. Examples of such fatty esters include, for example, methyl linoleate, ethyl linoleate, methyl eicosadienoic acid, ethyl eicosadienoic acid, methyl docosadienoic acid, ethyl docosadienoic acid and the like.
[0024]
　After sulfidation fatty acid ester as described above, the method of purifying sulfurized ester represented by the general formula (1) or (2) may be utilized any method without particular limitation. For example, like extracts by gel chromatography on silica gel.
[0025]
　Specific examples of the sulfurized ester represented by the general formula (1) and (2), 3-nonanoyl dichroic methyl ester-5-hexyl - thiolane, 3-nonanoyl dichroic ethyl ester-5-hexyl - thiolane, 3- Nonanoikku propyl ester 5-hexyl - thiolane, 3-dodecanoate dichroic methyl ester 5-propyl - thiolane, 3-dodecanoate dichroic ethyl ester 5-propyl - thiolane, 3-dodecanoate dichroic propyl ester 5-propyl - thiorane , 3-hexanoic methyl ester-5-nonyl - thiolane, 3-hexanoic ethyl ester-5-nonyl - thiolane, 3-hexanoic propyl ester 5-nonyl - thiolane, 3-nonanoyl dichroic methyl ester - 5-hexyl-1,2-dithiolane, 3-Nonanoikkuechi Ester 5-hexyl-1,2-dithiolane, 3-nonanoyl dichroic propyl ester 5-hexyl-1,2-dithiolane, 3-dodecanoate dichroic methyl ester 5-propyl-1,2-dithiolane, 3-dodeca Roh dichroic ethyl ester 5-propyl-1,2-dithiolane, 3-dodecanoate dichroic propyl ester 5-propyl-1,2-dithiolane, 3-hexanoic methyl ester 5- nonyl-1,2-dithiolane , 3-hexanoic ethyl ester-5-nonyl-1,2-dithiolane, 3-hexanoic propyl ester 5-nonyl-1,2-dithiolane, and the like.
[0026]
　Sulfurized ester represented by the general formula (1) and (2) may be used alone, or may be mixed and used. The mixing ratio of the case of using mixed to is arbitrary, 1 weight ratio: 2 to 2: is preferably used as a mixture of 1.
[0027]
　[A2] component in (A) component of the lubricating oil composition of the present invention is a sulfurized ester represented by the following general formula (3).
[0028]
[Formula 3]

[0029]
　R in the general formula (3) 1 and R 2 are each independently hydrogen atom or a hydrocarbyl group. However, R 1 , R 2 is either or both is a hydrocarbyl group.
　The number of carbon atoms of the hydrocarbyl group is not particularly limited, is usually 1-24, preferably 1-12, more preferably 1-6, more preferably 1-3. Examples of the hydrocarbyl group include a methyl group, an ethyl group, a propyl group, an alkyl group such as isopropyl group; a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cycloalkyl group such as cyclohexyl group; a phenyl group, cresyl group, etc. it can be exemplified aryl groups.
　Alkyl group is preferred from the viewpoint of adsorbing and oxidation stability of a lubricating surface Among these, a methyl group, an ethyl group are particularly preferred.
[0030]
　L in the general formula (3), n, m and o are each individually an integer of 2 or more, the sum of l and m is the sum of 12-20, n and o is 12-20.
　the sum of the sum or n and o of l and n is decreased solubility base oil with less than 12, whereas when it exceeds 20 storage stability at low temperatures decreases.
[0031]
　The x in the general formula (3) is an integer of 1 to 3, preferably 1 or 2. x is higher reduction or copper corrosiveness of the antioxidant capacity greater than 3.
[0032]
　Sulfurized ester represented by the general formula (3) is for one of the fatty acid or fatty acid ester 2 molecule having an unsaturated bond is bridged by a sulfur atom, it can be obtained as a sulfide of the above fatty acids or fatty acid esters it can. In this case two molecules of crosslinking may be a different compound may be the same compound. Such fatty acids or fatty acid esters, for example, oleic acid, methyl oleate, ethyl oleate, glyceride oleate.
[0033]
　After sulfidation fatty acid ester as described above, the method of purifying sulfurized ester represented by the general formula (3) may be utilized any method without particular limitation. For example, like extracts by gel chromatography on silica gel.
[0034]
　Specific examples of the sulfurized ester represented by formula (3) include sulfides of methyl oleate.
[0035]
　[A3] component in (A) component of the lubricating oil composition of the present invention is a sulfur compound represented by the following general formula (4).
[0036]
[Chemical Formula 4]

[0037]
　P and q in the general formula (4) are each individually an integer of 5 or more, preferably 6 or more, more preferably 7 or more. p and q are undesirable because solubility is decreased less than 5 with respect to the base oil. On the other hand, although no particular limitation on the upper limit of p and q, it is usually preferably 17 or less, more preferably 9 or less.
　Also r in the general formula (4) is an integer of 1-3. oxidative stability improvement of r when exceeds 3 lubricating oil composition tends to become insufficient.
[0038]
　Method for producing a sulfur compound represented by the general formula (4) is not particularly limited, as the product only needs to be obtained these compounds.
　For example, it can be obtained by one hydrocarbon compound having an unsaturated bond in its molecular structure (olefin) sulfide 2 molecules (sulfurized olefin). Examples of such olefins include 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene and 1-hexadecene, 1-octadecene, and the like. Olefins binding at this time be the same compound or a different compound.
[0039]
　Methods of purifying sulfur compound represented by the general formula produced by the sulfurization processing of olefins as described above (4) may be utilized any method without particular limitation. For example, like extracts by gel chromatography on silica gel.
[0040]
　Specific examples of the sulfur compound represented by the general formula (4), for example sulfide dicapryl, disulfide dicapryl trisulfide dicapryl, sulfide dilauryl disulfide dilauryl trisulfide dilauryl sulfide dimyristyl, disulfide dimyristyl trisulfide dimyristyl, sulfide dicetyl, disulfide dicetyl, trisulfide dicetyl and the like.
[0041]
　[A4] component in (A) component of the lubricating oil composition of the present invention, more than 50 mole% of the total fatty acids constituting the fat or oil is a sulfurized fat and oil obtained from oil linoleic acid.
[0042]
　Fat used as a raw material, fat 50 mole% of the total fatty acids constituting or more, preferably fat than 60 mol% is linoleic acid. The fat content is less than 50 mole% of linoleic acid, can not be used as a high additive viscosity of the sulfide obtained by treating sulfide.
[0043]
　The fats least 50 mol% of the total fatty acids constituting the fat or oil is linoleic acid, e.g., safflower oil, sunflower oil, and soybean oil.
[0044]
　Fat, as long as the content of linoleic acid is not less than 50 mol%, it may be a mixture of two or more oils. The content of linoleic acid, such as olive oil may be mixed oil of less than 50 mol%.
[0045]
　Oil is not particularly limited to the method for obtaining a sulfurized fats and sulfurized treatment, any method can be used. For example, JP-B-58-17797 and JP Kokoku 2-9640 JP thereof include a method disclosed in JP-A-2000-239693.
[0046]
　The content of the (A) component is 10 mass ppm or the total amount of the composition as a sulfur element content is preferably not less than 15 mass ppm, further preferably not less than 20 mass ppm. On the other hand, the upper limit is not more than 400 mass ppm, preferably not more than 300 mass ppm, more preferably 200 mass ppm or less. The content of component [A] can not be obtained sufficient effect with less than 10 ppm by weight, resistance to sludge formation and corrosion of the lubricating oil composition exceeds 400 ppm by mass tends to decrease.
[0047]
　The lubricating oil composition of the present invention, as component [B] contains a chain terminator.
[0048]
　The chain terminating agent, specifically, for example, commonly Hin used hindered phenol compound and an aromatic amine compound as an antioxidant, and the like hindered amine compounds. Among these, hindered phenol is preferable.
[0049]
　Examples of the hindered phenol-based compound, specifically, 4,4'-methylenebis (2,6-di -tert- butylphenol), 4,4'-bis (2,6-di -tert- butylphenol), 4 , 4'-bis (2-methyl -6-tert-butylphenol), 2,2'-methylenebis (4-ethyl -6-tert-butylphenol), 2,2'-methylenebis (4-methyl -6-tert butylphenol), 4,4'-butylidene bis (3-methyl -6-tert-butylphenol), 4,4'-isopropylidene-bis (2,6-di -tert- butylphenol), 2,2'-methylenebis (4- methyl-6-nonylphenol), 2,2'-iso butylidene bis (4,6-dimethylphenol), 2,2'-methylenebis (4-methyl-6 - cyclohexyl phenol), 2,6-di -tert- butyl-4-methylphenol, 2,6-di -tert- butyl-4-ethylphenol, 2,4-dimethyl -6-tert-butylphenol, 2,6 - di-tert.-alpha-dimethylamino -p- cresol, 2,6-di -tert- butyl -4 (N, N'-dimethylaminomethyl phenol), 4,4'-thiobis (2-methyl-6- tert- butylphenol), 4,4'-thiobis (3-methyl -6-tert- butylphenol), 2,2'-thiobis (4-methyl -6-tert- butylphenol), bis (3-methyl-4-hydroxy -5-tert-butylbenzyl) sulfide, bis (3,5-di -tert- butyl-4-hydroxybenzyl) sulfide, 2,2 ' - thio - diethylene bis [3- (3,5-di -tert- butyl-4-hydroxyphenyl) propionate], octyl-3- (3,5-di -tert- butyl-4-hydroxyphenyl) propionate, tridecyl 3- (3,5-di -tert- butyl-4-hydroxyphenyl) propionate, pentaerythrityl - tetrakis [3- (3,5-di -tert- butyl-4-hydroxyphenyl) propionate], octadecyl - 3- (3,5-di -tert- butyl-4-hydroxyphenyl) propionate, and mixtures thereof.
　These molecular weight 240 or more hindered phenol compounds, among the high decomposition temperature, since the antioxidant effect is exhibited even at higher temperatures conditions, more preferably used.
[0050]
　Examples of the aromatic amine compound, specifically, a phenyl -α- naphthylamine, alkylphenyl -α- naphthylamine, dialkyldiphenylamines, N, N'-diphenyl -p- phenylenediamine, N- alkyl aniline, N, N ' - dialkyl anilines, N- alkyl benzidine, 4,4-methylenebis (N, N'-dimethyl aniline), and mixtures thereof. Examples of the alkyl group include straight-chain or branched alkyl group having 1 to 20 carbon atoms.
[0051]
　As the hindered amine compound, the specific examples, 2,2,6,6-tetramethyl-4-piperidyl - carboxylic acid ester. Examples of the carboxylic acid include straight-chain or branched carboxylic acids having 8 to 20 carbon atoms.
[0052]
　The content of the chain terminator is not particularly limited, the total amount of the composition, preferably 0.01 to 10 mass%, more preferably 0.05 to 5 mass%, more preferably 0. 1 to 1 mass%.
　It is sufficient antioxidant properties are obtained for the content of the chain terminator and 0.01 mass% or more, and a sufficient solubility in the base oil is obtained and by 10 mass% or less, sludge since the amount of generation is decreased, respectively preferable.
[0053]
　The lubricating oil composition of the present invention is characterized in that it contains substantially no sulfur-containing metal complex. The lubricating oil composition of the present invention, by containing no sulfur-containing metal complexes substantially realizes a low sludge properties.
[0054]
　The sulfur-containing metal complexes is meant broadly complexes general of an organic compound and a metal element containing a sulfur atom in the structure. The sulfur-containing metal complexes, e.g., zinc dithiophosphate compounds, zinc dithiocarbamate compound, molybdenum dithiophosphate compounds, molybdenum compounds dithiocarbamates.
[0055]
　Zinc dithiophosphate compounds, zinc dithiocarbamate compound, a molybdenum dithiophosphate compound and molybdenum dithiocarbamate compound is a compound respectively represented by the following general formula (5) to (8).
[Of 5]

[Formula 6]

[formula 7]

[of 8]

[0056]
　Equation (5) ~ (8), R 1 ~ R 16 , which may be the same or different, each represents a hydrocarbon group having 1 to 20 carbon atoms, X 1 and X 2 are each an oxygen atom or a sulfur atom a representative.
[0057]
　In the present invention, "not substantially contain sulfur-containing metal complexes", or not at all contain sulfur-containing metal complexes, only very small to negligible effect even when containing containing You say that you have not.
　More specifically, the content of the sulfur-containing metal complexes, the total amount of the composition as a metal element amount, preferably not more than 50 mass ppm, more preferably less than 20 ppm by mass, more preferably not more than 10 mass ppm , most preferably 0 mass ppm.
[0058]
　The lubricating oil composition of the present invention can be obtained lubricating oil composition excellent in stability and low sludge oxidation the above configuration, in order further enhance its performance, or the required performance as a lubricating oil composition the purpose of further imparting, can be added a known lubricating oil additives.
　Such additives include, for example, metallic detergent, such as calcium sulfonate; wetting agents such as diethylene glycol monoalkyl ethers, acrylic polymers, paraffin wax, microcrystalline wax, slack wax, film-forming agent such as polyolefin waxes; fatty amine salts water displacing agent; graphite, fluorinated graphite, molybdenum disulfide, boron nitride, solid lubricants such as polyethylene powder; amines, alkanolamines, amides, carboxylic acids, carboxylic acid salts, sulfonic acid salts, phosphoric acid, phosphate , corrosion inhibitors, such as partial esters of polyhydric alcohols; benzotriazole, metal deactivators thiadiazole; methyl silicone, fluorosilicone, antifoaming agents such as polyacrylates, alkenylsuccinic acid imide, benzylamine, polyalkenylamine Ashless dispersants such as Minoamido; and the like. In an amount such that the content is not particularly limited, the total content of these known additive is 0.1 to 10 mass% in the total amount of the lubricating oil composition reference of Using these known additives preferably added.
[0059]
　The kinematic viscosity of the lubricating oil composition of the present invention is not particularly limited, from the viewpoint of supply ease into the lubricating site, the kinematic viscosity at 40 ° C., 100 mm 2 is preferably from / s, 80 mm 2 / s more preferably less is, 50 mm 2 and more preferably less / s.
　Meanwhile, the kinematic viscosity at 40 ° C., 1 mm 2 preferably at / s or more, 2 mm 2 more preferably / s or more, 3 mm 2 and further preferably / s or more.
[0060]
　The lubricating oil composition of the present invention, it is possible to achieve both excellent oxidative lifetime and low sludge properties, can be suitably used in a wide range of applications. In particular, in order to further exert its effect when the temperature used, such as 120 ° C. or less is low, it can be suitably used a combustion chamber as a machine lubricating oil without lubrication.
Example
[0061]
　The following examples illustrate the present invention but the present invention is not limited to these examples.
　Incidentally, the base oil and additives used in Examples and Comparative Examples are as follows.
[0062]
[Lubricating base oil]
　base oil 1; Kuang highly refined base oil (fully aromatic content: 0.3 mass%, sulfur rating: 0 mass ppm, 40 ℃ kinematic viscosity: 35mm 2 / S, a viscosity index: 120 )
[0063]
[Component [A] sulfur-containing compounds]
([A1]
　component); A1-1; general formula (1) and the weight ratio of cyclic sulfide ester represented by (2) 1: a mixture of 1 (R: methyl group , a = 5, b = 7 , c = 4, d = 7, sulfur content: 13
　wt%) A1-2; formula (1) and (the weight ratio of cyclic sulfide ester represented by 2) 1: 1 a mixture of (R: ethyl, a = 5, b = 7 , c = 4, d = 7, sulfur content: 12.5
　wt%) A1-1, A1-2 is methyl linoleate or ethyl linoleate the resulting sulfide ester was sulfurized, the sulfurized ester, a fraction extracted by gel chromatography on silica gel. Resulting A1-1, A1-2 is C 13 was identified by -NMR, FD-MS and elemental analysis.
[0064]
([A2]
　component); A2-1; general formula (3) a mixture of sulfurized methyl oleate represented by (R 1 , R 2 : methyl group, l + m = 14, n + o = 14, x = 1 ~ 3, sulfur amount: 10.5
　wt%) A2-2; mixture of sulfurized ethyl oleate represented by the general formula (3) (R 1 , R 2 : an ethyl group, l + m = 14, n + o = 14, x = 1 ~ 3, sulfur content: 10
　wt%) A2-1, A2-2 is extracted 150g of silica gel after packed into a glass tube, filled with sulfurized ester 1.5 g (DOG Co. M10), hexane 150 ml, of toluene 100ml After the obtained fractions extracted with a mixed solvent 100ml 5% and 95% toluene acetone.
([A3]
　component); A3-1; formula (4) Sulfur compounds represented by (p, q = 9, r = 1, sulfur content: 8.6
　wt%) A3-2; formula (4 sulfur compounds represented by) (p, q = 7, r = 2 ~ 3, sulfur content: 22 wt%)
　Note, A3-1, A3-2 are each sulfide 1-dodecene and 1-decene give a sulfurized olefin, a sulfurized olefin, a fraction extracted by gel chromatography on silica gel. Resulting A3-1, A3-2 is C 13 was identified by -NMR, FD-MS and elemental analysis.
[0065]
([A4] Ingredients: sulfurized
　fats) A4-1; safflower oil sulfurized fats obtained by sulfurization process (linoleic acid content of 60 to 80 mol%), sulfur content: 14
　wt% A4-2; sunflower oil sulfurized fats and oils obtained by sulfurization process (linoleic acid content of 50 to 75 mol%), sulfur content: 15 wt%
　Incidentally, sesame oil (linoleic acid content of 35 to 45 mol%) and olive oil (linoleic acid content 4 was subjected to the same sulfurization treatment with regard to 12 mol%). However, sulfurized fats and oils obtained was unsuitable as high viscosity additive.
[0066]
[[A] a sulfur-containing compound other than the component)]
　S-1; dibenzyl disulfide (manufactured by Tokyo Kasei Kogyo Co., Ltd., sulfur content: 26 wt%)
　S-2; a mixture of sulfurized methyl oleate (Formula (3) in, R 1 , R 2 : methyl group, l + m = 14, n + o = 14, x = 1 ~ 7, sulfur content: 18
　wt%) S-3; mixture of sulfurized methyl oleate in (formula (3), R 1 , R 2 : methyl group, l + m = 14, n + o = 14, x = 4 ~ 7, sulfur content: 21
　wt%) S-4; r is sulfur compounds out of the provisions of the general formula (4) (formula in (4), p, q = 9, r = 4 ~ 9, sulfur content: 32
　wt%) S-5; sulfide compound represented by the following formula (sulfur content: 30 wt%)
[of

　9] S- 6: sulfurized fats and oils (produced by DIC Corporation, trade name "GS225", sulfur content: 15% by mass)
　S-7: sulfide ester (manufactured by DIC Corporation, trade name "GS235", sulfur content: 18% by mass)
[0067]
[B] chain
　terminators] B-1; phenol antioxidant (di -tert- butyl -p-
　cresol) B-2; a phenolic antioxidant (BASF's trade name "L135")
[0068]
(Examples and Comparative Examples)
　described the amount and performance of Tables 1 to various lubricating base oil and additives 4. Amount of base oil (mass%), the addition amount of each additive (wt%) is the total amount of the lubricating oil composition reference.
　For each of the obtained compositions was evaluated by ALCOA the following tests oxidative stability and anti-sludge properties. This test is known to have good correlation with the test turbine oil oxidation stability as specified in ASTM-D943 (abbreviated as TOST).
[0069]
(ALCOA
　test) were taken in a flask of 115ml test oil 13 ml, copper wire # 240 polishing as a catalyst (1.6 mm × 5 cm) placed five. Then purge the flask with oxygen gas, sealed quickly mercury manometer. Then left for 1 hour the flask was immersed in an oil bath at 115 ° C.. Read the manometer of differential pressure at this time, it is recorded as the test time 0h. This value was commonly approximately 200mmHg for all test oils used in this experiment. After that the pressure difference was measured every predetermined time, drop in the oxygen pressure was oxidized life of test oil time becomes equal to or greater than 50 mmHg. Moreover, viewing the sample oil after the test, to confirm the presence or absence of insoluble matter (sludge).
[0070]
[Table 1]

[0071]
[Table 2]

[0072]
[table 3]

[0073]
[Table 4]

The scope of the claims
[Claim 1]
　The lubricant base oil, a cyclic sulfide ester represented by [A] [A1] represented by the following general formula (1) and / or (2), sulfurized ester represented by [A2] represented by the following general formula (3), [A3] below formula (4) sulfur compounds represented by, and [A4] a sulfur-containing compound at least 50 mol% of the total fatty acids constituting the fat or oil is selected from the group consisting of sulfurized fats and oils derived from fats and oils is linoleic acid, and [ B] a lubricating oil composition containing a chain terminator, [a] is 10 to 400 ppm by weight as a sulfur element content content in the lubricating oil composition reference component, and a sulfur-containing metal complexes substantially the lubricating oil composition characterized in that it does not contain.
[Chemical formula 1]

(Equation (1), (R in 2) represents a hydrocarbyl group, a, b, c, d are each independently an integer of 3 or more, the sum of a and b 8 ~ 14, the sum of c and d is 7-13 and is. equation (3) R in 1 and R 2 indicate each individual hydrogen atom or a hydrocarbyl group. provided that at least one is a hydrocarbyl group .l, n, m , o is are each independently an integer of 2 or more, .x the sum of l and m is the sum of 12-20, n and o is 12 to 20 represents an integer of 1-3. equation (4) the p, q are each an individual integer of 5 or more, r is an integer of 1-3.)
[Claim 2]
　[B] the lubricating oil composition of claim 1, chain terminator is characterized in that it is a hindered phenol.
[Claim 3]
　The lubricating oil composition according to claim 1 or 2 sulfur content of the lubricating base oil is equal to or less than 10 mass ppm.
[Claim 4]
　The lubricating oil composition according to any one of claims 1 to 3, characterized in that used the combustion chamber as a machine lubricating oil without lubrication.