Classifications

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  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M141/00—Lubricating compositions characterised by the additive being a mixture of two or more compounds covered by more than one of the main groups C10M125/00 - C10M139/00, each of these compounds being essential
  • C10M141/10—Lubricating compositions characterised by the additive being a mixture of two or more compounds covered by more than one of the main groups C10M125/00 - C10M139/00, each of these compounds being essential at least one of them being an organic phosphorus-containing compound
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  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M169/00—Lubricating compositions characterised by containing as components a mixture of at least two types of ingredient selected from base-materials, thickeners or additives, covered by the preceding groups, each of these compounds being essential
  • C10M169/04—Mixtures of base-materials and additives
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  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2207/00—Organic non-macromolecular hydrocarbon compounds containing hydrogen, carbon and oxygen as ingredients in lubricant compositions
  • C10M2207/28—Esters
  • C10M2207/287—Partial esters
  • C10M2207/288—Partial esters containing free carboxyl groups
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  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2207/00—Organic non-macromolecular hydrocarbon compounds containing hydrogen, carbon and oxygen as ingredients in lubricant compositions
  • C10M2207/28—Esters
  • C10M2207/287—Partial esters
  • C10M2207/289—Partial esters containing free hydroxy groups
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  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2215/00—Organic non-macromolecular compounds containing nitrogen as ingredients in lubricant compositions
  • C10M2215/02—Amines, e.g. polyalkylene polyamines; Quaternary amines
  • C10M2215/04—Amines, e.g. polyalkylene polyamines; Quaternary amines having amino groups bound to acyclic or cycloaliphatic carbon atoms
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  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2215/00—Organic non-macromolecular compounds containing nitrogen as ingredients in lubricant compositions
  • C10M2215/02—Amines, e.g. polyalkylene polyamines; Quaternary amines
  • C10M2215/04—Amines, e.g. polyalkylene polyamines; Quaternary amines having amino groups bound to acyclic or cycloaliphatic carbon atoms
  • C10M2215/044—Amines, e.g. polyalkylene polyamines; Quaternary amines having amino groups bound to acyclic or cycloaliphatic carbon atoms having cycloaliphatic groups
• • C—CHEMISTRY; METALLURGY
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  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2219/00—Organic non-macromolecular compounds containing sulfur, selenium or tellurium as ingredients in lubricant compositions
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2219/00—Organic non-macromolecular compounds containing sulfur, selenium or tellurium as ingredients in lubricant compositions
  • C10M2219/02—Sulfur-containing compounds obtained by sulfurisation with sulfur or sulfur-containing compounds
  • C10M2219/022—Sulfur-containing compounds obtained by sulfurisation with sulfur or sulfur-containing compounds of hydrocarbons, e.g. olefines
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2219/00—Organic non-macromolecular compounds containing sulfur, selenium or tellurium as ingredients in lubricant compositions
  • C10M2219/02—Sulfur-containing compounds obtained by sulfurisation with sulfur or sulfur-containing compounds
  • C10M2219/024—Sulfur-containing compounds obtained by sulfurisation with sulfur or sulfur-containing compounds of esters, e.g. fats
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2219/00—Organic non-macromolecular compounds containing sulfur, selenium or tellurium as ingredients in lubricant compositions
  • C10M2219/06—Thio-acids; Thiocyanates; Derivatives thereof
  • C10M2219/062—Thio-acids; Thiocyanates; Derivatives thereof having carbon-to-sulfur double bonds
  • C10M2219/066—Thiocarbamic type compounds
• • C—CHEMISTRY; METALLURGY
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  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2219/00—Organic non-macromolecular compounds containing sulfur, selenium or tellurium as ingredients in lubricant compositions
  • C10M2219/08—Thiols; Sulfides; Polysulfides; Mercaptals
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2219/00—Organic non-macromolecular compounds containing sulfur, selenium or tellurium as ingredients in lubricant compositions
  • C10M2219/08—Thiols; Sulfides; Polysulfides; Mercaptals
  • C10M2219/082—Thiols; Sulfides; Polysulfides; Mercaptals containing sulfur atoms bound to acyclic or cycloaliphatic carbon atoms
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2219/00—Organic non-macromolecular compounds containing sulfur, selenium or tellurium as ingredients in lubricant compositions
  • C10M2219/08—Thiols; Sulfides; Polysulfides; Mercaptals
  • C10M2219/082—Thiols; Sulfides; Polysulfides; Mercaptals containing sulfur atoms bound to acyclic or cycloaliphatic carbon atoms
  • C10M2219/086—Thiols; Sulfides; Polysulfides; Mercaptals containing sulfur atoms bound to acyclic or cycloaliphatic carbon atoms containing sulfur atoms bound to carbon atoms of six-membered aromatic rings
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2219/00—Organic non-macromolecular compounds containing sulfur, selenium or tellurium as ingredients in lubricant compositions
  • C10M2219/10—Heterocyclic compounds containing sulfur, selenium or tellurium compounds in the ring
  • C10M2219/104—Heterocyclic compounds containing sulfur, selenium or tellurium compounds in the ring containing sulfur and carbon with nitrogen or oxygen in the ring
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2219/00—Organic non-macromolecular compounds containing sulfur, selenium or tellurium as ingredients in lubricant compositions
  • C10M2219/10—Heterocyclic compounds containing sulfur, selenium or tellurium compounds in the ring
  • C10M2219/104—Heterocyclic compounds containing sulfur, selenium or tellurium compounds in the ring containing sulfur and carbon with nitrogen or oxygen in the ring
  • C10M2219/106—Thiadiazoles
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2223/00—Organic non-macromolecular compounds containing phosphorus as ingredients in lubricant compositions
  • C10M2223/02—Organic non-macromolecular compounds containing phosphorus as ingredients in lubricant compositions having no phosphorus-to-carbon bonds
  • C10M2223/04—Phosphate esters
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2223/00—Organic non-macromolecular compounds containing phosphorus as ingredients in lubricant compositions
  • C10M2223/02—Organic non-macromolecular compounds containing phosphorus as ingredients in lubricant compositions having no phosphorus-to-carbon bonds
  • C10M2223/04—Phosphate esters
  • C10M2223/043—Ammonium or amine salts thereof
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
  • C10M2223/00—Organic non-macromolecular compounds containing phosphorus as ingredients in lubricant compositions
  • C10M2223/02—Organic non-macromolecular compounds containing phosphorus as ingredients in lubricant compositions having no phosphorus-to-carbon bonds
  • C10M2223/04—Phosphate esters
  • C10M2223/047—Thioderivatives not containing metallic elements
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10N—INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
  • C10N2030/00—Specified physical or chemical properties which is improved by the additive characterising the lubricating composition, e.g. multifunctional additives
  • C10N2030/06—Oiliness; Film-strength; Anti-wear; Resistance to extreme pressure
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10N—INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
  • C10N2030/00—Specified physical or chemical properties which is improved by the additive characterising the lubricating composition, e.g. multifunctional additives
  • C10N2030/10—Inhibition of oxidation, e.g. anti-oxidants
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10N—INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
  • C10N2040/00—Specified use or application for which the lubricating composition is intended
  • C10N2040/04—Oil-bath; Gear-boxes; Automatic transmissions; Traction drives

Definitions

• the present invention relates to a lubricating oil composition and, more particularly, to a lubricating oil composition which exhibits excellent anti-seizure performance, excellent anti-fatigue performance, and reduced sludge formation in an oxidation test, and which is particularly suitable for use with a step-up gear for wind power generation.
• Wind power generation making use of renewable energy, is expected to increase in demand, as it will reduce the environment load and contribute to the conservation of fossil fuel, which have become important issues in recent years.
• kinetic energy of wind is transformed into power by means of rotors including propellers which are rotated by wind.
• a power generator is operated to produce electric energy.
• a step-up gear is employed to elevate the rotation rate of rotors, which is relatively slow, so as to improve power generation efficiency of the power generator.
• a variety of step-up gears are known in the art, and among them, a planetary gear-type power transmission apparatus is widely employed.
• a step-up gear oil composition is used and is required to exhibit excellent anti-seizure performance and anti-fatigue performance, such as anti-FZG-micropitting performance, and to ensure minimization in amount of formed sludge in an oxidation test.
• a lubricating oil composition for use in a step-up gear used in a wind power generator which composition contains (a) an extreme pressure compound including a sulfur compound, (b) a mixture of a hydrocarbylamine compound and an alkyl phosphorothioate compound, (c) a friction-controlling compound, and (d) a base oil (see, for example, Patent Document 1).
• the proposed lubricating oil composition is not thought to exhibit completely satisfactory performance required for step-up gear oil compositions for wind power generation.
• an object of the present invention is to provide a lubricating oil composition which has excellent anti-seizure performance, anti-fatigue performance, and reduced sludge formation in an oxidation test, and which is suitably used with a step-up gear for wind power generation.
• the present inventor has carried out extensive studies for the development of a lubricating oil composition which is excellent in the aforementioned characteristics, and has found that the object can be attained by a lubricating oil composition containing a base oil and (A) a specific acidic alkyl phosphate ester, (B) a specific alkylamine, (C) and a specific sulfur compound, in combination, and having a specific P/S ratio.
• the present invention has been accomplished on the basis of this finding. Accordingly, the present invention provides the following.
• the present invention can provide a lubricating oil composition which has excellent anti-seizure performance, excellent anti-fatigue performance (e.g., anti-FZG-micropitting performance), and reduced sludge formation in an oxidation test, and which is suitably used with a step-up gear for wind power generation.
• the base oil employed in the lubricating oil composition of the present invention preferably has a kinematic viscosity as determined at 40°C of 30 to 800 mm 2 /s and a viscosity index of 80 or higher.
• a kinematic viscosity as determined at 40°C of 30 to 800 mm 2 /s and a viscosity index of 80 or higher.
• the kinematic viscosity (40°C) is more preferably 32 to 680 mm 2 /s, particularly preferably 100 to 500 mm 2 /s.
• the viscosity index is 80 or higher, variation in viscosity to temperature variation is small.
• the viscosity index is more preferably 100 or higher, still more preferably 130 or higher.
• the pour point is preferably -25°C or lower. When the pour point is -25°C or lower, the produced lubricating oil composition can possess sufficient fluidity event at low temperature.
• the pour point is more preferably -30°C or lower, still more preferably -40°C or lower.
• the aforementioned kinematic viscosity and viscosity index are determined in accordance with JIS K 2283, and the pour point is determined in accordance with JIS K 2265.
• the type of the base oil may be either mineral oil or synthetic oil may be used.
• mineral oil include paraffin-base mineral oil, intermediate mineral oil, and naphthene-base mineral oil. Specific examples include solvent-refined or hydrogenated light neutral oil, medium neutral oil, heavy neutral oil, and bright stock.
• a variety of conventional synthetic oils may be employed.
• Examples of the synthetic oil include poly- ⁇ -olefin, polybutene, polyol ester, dibasic acid esters, phosphate esters, polyphenyl ethers, alkylbenzenes, alkylnaphthalenes, polyoxyalkylene glycols, neopentyl glycol, silicone oil, trimethylolpropane, pentaerytheritol, and hindered esters.
• These base oils may be used singly or in combination of two or more species, and mineral oil and synthetic oil may be used in combination.
• the C6 to C20 acidic alkyl phosphate ester serving as component (A) may be a compound represented by formula (II):
• X 1 represents a hydrogen atom or a C6 to C20 alkyl group
• X 2 represents a C6 to C20 alkyl group
• the C6 to C20 alkyl group may be linear, branched, or cyclic. Examples of the alkyl group include hexyl, octyl, decyl, dodecyl, tetradecyl, hexadecyl, octadecyl, and icosyl. Of these, C10 to C18 alkyl groups are preferred.
• Examples of the acidic alkyl phosphate ester represented by formula (II) include acidic phosphate monoesters such as monooctyl acid phosphate, monodecyl acid phosphate, monoisodecyl acid phosphate, monolauryl acid phosphate, mono(tridecyl) acid phosphate, monomyristyl acid phosphate, monopalmityl acid phosphate, monostearyl acid phosphate; and acidic phosphate diesters such as dioctyl acid phosphate, didecyl acid phosphate, diisodecyl acid phosphate, dilauryl acid phosphate, di(tridecyl) acid phosphate, dipalmityl acid phosphate, and distearyl acid phosphate.
• acidic phosphate monoesters such as monooctyl acid phosphate, monodecyl acid phosphate, monoisodecyl acid phosphate, monolauryl acid
• the aforementioned acidic alkyl phosphate esters serving as component (A) may be used singly or in combination of two or more species.
• the amount(s) of the phosphate ester(s) as reduced to P is (are) 150 to 500 ppm by mass with respect to the amount of lubricating oil composition.
• the P content of the composition is less than 150 ppm by mass, anti-seizure performance is insufficient, whereas when the P content is in excess of 500 ppm by mass, anti-fatigue performance (anti-FZG-micropitting performance) decreases.
• the P content is preferably 250 to 450 ppm by mass, more preferably 350 to 400 ppm by mass.
• the anti-seizure performance and anti-fatigue performance are assessed through the following test methods.
• the test is performed in accordance with ASTM D 5182-91, at 90°C and 1,450 rpm for 15 minutes.
• the score is represented by a load stage at which scuffing occurs.
• the test is performed in accordance with ASTM D 2782, at 800 rpm for 10 minutes.
• the score is represented by the maximum load (lbs) at which no seizure occurs.
• the test is performed through the same procedure as employed in the aforementioned FZG seizure test, except that the score is represented by a load stage at which micropitting occurs.
• the dialkylamine and/or trialkylamine serving as component (B) preferably has a C6 to C20 alkyl group.
• the dialkylamine include dihexylamine, dicyclohexylamine, dioctylamine, dilaurylamine, and distearylamine.
• the trialkylamine include trihexylamine, tricyclohexylamine, trioctylamine, trilaurylamine, and tristearylamine.
• the aforementioned dialkylamines and/or trialkylamines serving as component (B) may be used singly or in combination of two or more species.
• trialkylamines are preferred from the viewpoint of performance.
• a monoalkylamine is employed, anti-seizure performance is impaired.
• Component (B) is incorporated into the composition in such an amount that the ratio by mass of P contained in component (A) to N contained in component (B) is adjusted to 1.7 to 2.1.
• the mass ratio is 1.7 or higher, good anti-seizure performance is attained, whereas when the mass ratio is 2.1 or less, sludge formation in an oxidation test is prevented.
• the sulfur compound serving as component (c-1) has a poly-sulfur bond which is equal to or longer than -S-S-S-, a large amount of sludge forms in the Indiana oxidation test, and anti-FZG-micropitting performance decreases.
• the S content of the molecule is less than 15 mass%, the effect of the sulfur compound commensurate with the amount of addition cannot be attained, and in some cases, anti-seizure performance is poor.
• the sulfur compound serving as component (c-1) and having the aforementioned properties include the following compounds:
• Examples of the olefin sulfide include compounds represented by formula (III): R 1 -S a -R 2 (I) (wherein R 1 represents a C2 to C15 alkenyl group, R 2 represents a C2 to C15 alkyl group or alkenyl group, and a is 1 or 2). These compounds are produced through reaction between a C2 to C15 olefin or a dimer to tetramer thereof and a sulfidizing agent such as sulfur or sulfur chloride.
• Examples of preferred olefins include propylene, isobutene, and diisobutene.
• Examples of the dihydrocarbyl mono- or disulfide include compounds represented by formula (IV): R 3 -S b -R4 (IV) (wherein R 3 and R 4 , which may be identical to or different from each other, each represent a C1 to C20 alkyl group, a cycloalkyl group, a C6 to C20 aryl group, a C7 to C20 alkylaryl group, or a C7 to C20 arylalkyl group, and b is 1 or 2).
• R 3 and R 4 are alkyl groups, these compounds are called alkyl sulfide.
• Examples of preferred dihydrocarbyl mono- or disulfides represented by formula (IV) include dibenzyl mono- or disulfide, various dinonyl mono- or disulfides, various didodecyl mono- or disulfides, various dibutyl mono- or disulfides, various dioctyl mono- or disulfides, various diphenyl mono- or disulfide, and various dicyclohexyl mono-or disulfide.
• Examples of preferred thiadiazole compounds include 2,5-bis(n-hexyldithio)-1,3,4-thiadiazole, 2,5-bis(n-octyldithio)-1,3,4-thiadiazole, 2,5-bis(n-nonyldithio)-1,3,4-thiadiazole, 2,5-bis(1,1,3,3-tetramethylbutyldithio)-1,3,4-thiadiazole, 3,5-bis(n-hexyldithio)-1,2,4-thiadiazole, 3,6-bis(n-octyldithio)-1,2,4-thiadiazole, 3,5-bis(n-nonyldithio)-1,2,4-thiadiazole, 3,5-bis(1,1,3,3-tetramethylbutyldithio)-1,2,4-thiadiazole, 4,5-bis(n-octyldithio)-1,2,3-thiadiazol
• dithiocarbamate compound examples include alkylene bisdialkyldithiocarbamates. Among them, those having a C1 to C3 alkylene group, a C3 to C20 linear or branched, saturated or unsaturated alkyl group, or a C6 to C20 cycloalkyl group are preferably employed. Specific examples of such dithiocarbamate compounds include methylene bisdibutyldithiocarbamate, methylene bis dioctyldithiocarbamate, and methylene bistridecyldithiocarbamate.
• ester compound having a disulfide structure examples include disulfide compounds represented by formula (V): R 5 OOC-A 1 -S-S-A 2 -COOR 6 (V) and disulfide compounds represented by formula (VI): R 11 OOC-CR 13 R 14 -CR 15 (COOR 12 )-S-S-R 20 (COOR 17 ) -CR 18 R 19 -COOR 16 ⁇ (VI).
• each of R 5 and R 6 represents a C1 to C30 hydrocarbyl group (preferably a C1 to C20, more preferably a C2 to C18, particularly preferably a C3 to C18 hydrocarbyl group).
• the hydrocarbyl group may be linear, branched, or cyclic, and may contain an oxygen atom, a sulfur atom, or a nitrogen atom.
• R 5 and R 6 may be identical to or different from each other.
• the two groups are preferably identical to each other.
• Each of A 1 and A 2 represents CR 7 R 8 or CR 7 R 8 -CR 9 R 10 , wherein each of R 7 to R 10 represents a hydrogen atom or a C1 to C20 hydrocarbyl group.
• the hydrocarbyl group is preferably a C1 to C12 hydrocarbyl group, more preferably a C1 to C8 hydrocarbyl group.
• a 1 and A 2 may be identical to or different from each other. From the viewpoint of production of the above compounds, the two groups are preferably identical to each other.
• each of R 11 , R 12 , R 16 , and R 17 represents a C1 to C30 hydrocarbyl group (preferably a C1 to C20, more preferably a C2 to C18, particularly preferably a C3 to C18 hydrocarbyl group).
• the hydrocarbyl group may be linear, branched, or cyclic, and may contain an oxygen atom, a sulfur atom, or a nitrogen atom.
• R 11 , R 12 , R 16 , and R 17 may be identical to or different from one another. From the viewpoint of production of the above compounds, these groups are preferably identical to one another.
• Each of R 13 to R 15 and R 18 to R 20 represents a hydrogen atom or a C1 to C5 hydrocarbyl group. For the reason of availability, these groups are preferably hydrogen atoms.
• disulfide compound represented by formula (V) include bis(methoxycarbonylmethyl) disulfide, bis(ethoxycarbonylmethyl) disulfide, bis(n-propoxycarbonylmethyl) disulfide, bis(isopropoxycarbonylmethyl) disulfide, bis(cyclopropoxycarbonylmethyl) disulfide, 1,1-bis(1-methoxycarbonylethyl) disulfide, 1,1-bis(1-methoxycarbonyl-n-propyl) disulfide, 1,1-bis(1-methoxycarbonyl-n-butyl) disulfide, 1,1-bis(1-methoxycarbonyl-n-hexyl) disulfide, 1,1-bis(1-methoxycarbonyl-n-octyl) disulfide, 2,2-bis(2-methoxycarbonyl-n-propyl) disulfide, ⁇ , ⁇ -bis( ⁇ -methoxycarbon
• disulfide compound represented by formula (VI) examples include tetramethyl dithiomalate, tetraethyl dithiomalate, tetra-1-propyl dithiomalate, tetra-2-propyl dithiomalate, tetra-1-butyl dithiomalate, tetra-2-butyl dithiomalate, tetraisobutyl dithiomalate, tetra-1-hexyl dithiomalate, tetra-1-octyl dithiomalate, tetra-1-(2-ethyl)hexyl dithiomalate, tetra-1-(3,5,5-trimethyl)hexyl dithiomalate, tetra-1-decyl dithiomalate, tetra-1-dodecyl dithiomalate, tetra-1-hexadecyl dithiomalate, tetra-1--
• sulfur compounds include sulfidized fats and oils such as sulfidized lard, sulfidized rape seed oil, sulfidized castor oil, sulfidized soy bean oil, and sulfidized rice bran oil; sulfidized fatty acids such as thioglycolic acid and thiooleic acid; dialkyl thiodipropionate compounds such as dilauryl thiodipropionate, distearyl thiodipropionate, and dimyristyl thiodipropionate; and a thioterpene compound formed through reaction between phosphorus pentasulfide and pinene.
• sulfidized fats and oils such as sulfidized lard, sulfidized rape seed oil, sulfidized castor oil, sulfidized soy bean oil, and
• the aforementioned sulfur compounds serving as component (c-1) may be used singly or in combination of two or more species.
• the component (c-1) is required to be incorporated into the lubricating oil composition in an amount of composition 0.2 to 0.6 mass% as reduced to S.
• S content is less than 0.2 mass%, anti-seizure performance is unsatisfactory, whereas when the S content is in excess of 0.6 mass%, anti-fatigue performance such as FZG micropitting resistance is impaired, and a large amount of sludge is generated in the Indiana oxidation test.
• the S content is preferably 0.3 to 0.5 mass%.
• the Indiana oxidation test is carried out through the following procedure.
• the test is carried out in accordance with the Indiana oxidation test method (Standard Oil Co.). Specifically, air is introduced into a sample (300 mL) at 10 L/hour and 121°C for 312 hours for causing forced deterioration. After the experiment, generated sludge is recovered by means of a Millipore filter and weighed.
• R represents a C6 to C20 hydrocarbyl group.
• the hydrocarbyl group represents a linear, branched, or cyclic C6 to C20 alkyl group or alkenyl group, a C6 to C20 aryl group, or a C7 to C20 aralkyl group.
• one or more alkyl groups may be attached to the corresponding aromatic ring.
• Three R-O- groups may be identical to or different from one another.
• Examples of the C6 to C20 alkyl group and alkenyl group include hexyls, octyls, decyls, dodecyls, tetradecyls, hexadecyls, octadecyls, cyclohexyl, hexenyls, octenyls, decenyls, dodecenyls, tetradecenyls, hexadecenyls, octadecenyls, and cyclohexenyl.
• Examples of the C6 to C20 aryl group include phenyl, tolyl, xylyl, decylphenyl, 2,4-didecylphenyl, and naphthyl.
• Examples of the C7 to C20 aralkyl group include benzyl, phenethyl, naphthylmethyl, methylbenzyl, methylphenethyl, and methylnaphthylmethyl.
• thiophosphoric acid trihydrocarbyl ester represented by formula (I) include trihexyl thiophosphate, tri-2-ethylhexyl thiophosphate, tris(decyl) thiophosphate, trilauryl thiophosphate, trimyristyl thiophosphate, tripalmityl thiophosphate, tristearyl thiophosphate, trioleyl thiophosphate, tricresyl thiophosphate, trixylyl thiophosphate, tris(decylphenyl) thiophosphate, and tris[2,4-isoalkyl(C 9 , C 10 )phenyl] thiophosphate.
• thiophosphoric acid trihydrocarbyl phosphates may be used singly or in combination of two or more species.
• the thiophosphoric acid trihydrocarbyl ester serving as component (c-2) is optionally added to the composition for further enhancing the effect of the sulfur compound serving as component (c-1).
• the amount of component (c-2) compound is preferably 0.1 to 1.0 mass% based on the total amount of the lubricating oil composition, more preferably 0.2 to 0.5 mass%.
• the total amount of P in the lubricating oil composition is adjusted to 150 to 500 ppm by mass.
• the lubricating oil composition of the present invention may further contain a polyol partial ester serving as component (D).
• the component (D) further prevents sludge formation in the Indiana oxidation test.
• No particular limitation is imposed on the polyol serving as a raw material of the polyol partial ester, and an aliphatic polyol is preferred.
• polyol examples include dihydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, trimethylene glycol, tetramethylene glycol, and neopentyl glycol; trihydric alcohols such as glycerin, trimethylolethane, and trimethylolpropane; and polyhydric ( ⁇ 4-valent) alcohols such as diglycerin, triglycerin, pentaerythritol, dipentaerythritol, mannit, and sorbit. No particular limitation is imposed on the number of ester bonds in the partial ester, so long as at least one hydroxyl group remains.
• the hydrocarbyl group forming the ester bond(s) is preferably a C6 to C20 alkyl group or alkenyl group.
• Examples include hexyls, octyls, decyls, dodecyls, tetradecyls, hexadecyls, octadecyls, hexenyls, octenyls, decenyls, dodecenyls, tetradecenyls, hexadecenyls, and octadecenyls.
• polyol partial ester examples include, but are not limited to, neopentyl glycol monolaurate, neopentyl glycol monomyristate, neopentyl glycol monopalmitate, neopentyl glycol monostearate, neopentyl glycol monoisostearate, trimethylolpropane mono- or dilaurate, trimethylolpropane mono- or dimyristate, trimethylolpropane mono- or dipalmitate, trimethylolpropane mono- or distearate, trimethylolpropane mono- or diisostearate, glycerin mono- or dilaurate, glycerin mono- or distearate, and glycerin mono-or diisostearate.
• these polyol partial esters may be used singly or in combination of two or more species as component (D).
• the amount of polyol partial ester(s) incorporated into the composition is generally about 5 to about 20 mass%, based on the total amount of the composition, more preferably 7 to 15 mass%, from the viewpoint of prevention of sludge formation in the Indiana oxidation test.
• At least one additive may be incorporated in accordance with needs, the additive being selected from among an ashless detergent-dispersant, an antioxidant, an anticorrosive, a metal deactivator, a viscosity index improver, a pour point depressant, a defoaming agent, etc.
• the ashless detergent-dispersant include succinimides, boron-containing succinimides, benzylamines, boron-containing benzylamines, succinate esters, and mono- or divalent carboxamides including fatty acid amides and succinamides.
• the antioxidant employed may be an amine-based antioxidant, a phenol-based antioxidant, or a sulfur-containing antioxidant, which are conventionally employed in lubricating oil. These antioxidants may be used singly or in combination of two or more species.
• the amine-based antioxidant include monoalkyldiphenylamine compounds such as monooctyldiphenylamine and monononyldiphenylamine; dialkyldiphenylamine compounds such as 4,4'-dibutyldiphenylamine, 4,4'-dipentyldiphenylamine, 4,4'-dihexyldiphenylamine, 4,4'-diheptyldiphenylamine, 4,4'-dioctyldiphenylamine, and 4,4'-dinonyldiphenylamine; polyalkyldiphenylamine compounds such as tetrabutyldiphenylamine, tetrahexyldiphenylamine, tetraoctyldip
• phenol-based antioxidant examples include monophenol compounds such as 2,6-di-tert-butyl-4-methylphenol, 2,6-di-tert-butyl-4-ethylphenol, and octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate; and diphenol compounds such as 4,4'-methylenebis(2,6-di-tert-butylphenol) and 2,2'-methylenebis(4-ethyl-6-tert-butylphenol).
• sulfur-containing antioxidant examples include 2,6-di-tert-butyl-4-(4,6-bis(octylthio)-1,3,5-triazin-2-ylamino)phenol; thioterpene compounds such as a reaction product between phosphorus pentasulfide and pinene; and dialkyl thiodipropionates such as dilauryl thiodipropionate and distearyl thiodipropionate.
• Examples of the anticorrosive include metal sulfonates and succinic acid esters, and examples of the metal deactivator include benzotriazole and thiadiazole.
• Examples of the viscosity index improver include polymethacrylates, dispersion-type polymethacrylates, olefin copolymers (e.g., etylene-propylene copolymer), dispersion-type olefin copolymers, and styrene copolymers (e.g., styrene-diene hydrogenated copolymer).
• Examples of the pour point depressant employed in the invention include polymethacrylates having a weight average molecular weight of 50,000 to 150,000.
• the defoaming agent is preferably a high-molecular-weight silicone defoaming agent or a polyacrylate defoaming agent. Incorporation of a defoaming agent such as a high-molecular-weight silicone defoaming agent into the composition of the invention effectively attains defoaming property.
• a defoaming agent such as a high-molecular-weight silicone defoaming agent
• examples of the high-molecular-weight silicone defoaming agent include organopolysiloxanes. Of these, fluorine-containing organopolysiloxanes such as trifluoropropylmethyl silicone oil are particularly preferred.
• the lubricating oil composition of the present invention is excellent in anti-seizure performance, excellent anti-fatigue performance (e.g., FZG micropitting resistance), and reduced sludge formation in an oxidation test.
• the composition can be employed as lubricating oils such as gear oil and bearing oil, and particularly suitable for a lubricating oil for use in a planetary gear-type power transmission apparatus in a wind power generator.
• the present invention is directed to a lubricating oil composition
• a lubricating oil composition comprising a base oil, components (A) to (C), and an optional component (D).
• the lubricating oil composition comprises a base oil, components (A) to (C), and a component (D).
• Stage 13 is a pass level.
• the test was carried out in accordance with a method described in the present specification.
• the pass level is 45 lbs or higher.
• Stage 9 is a pass level.
• Sludge level (determined by means of a Millipore filter) of 10 or less is a pass level.
• Lubricating oil compositions having a formulation shown in Table 1 were prepared, and characteristics of the compositions were assessed. Table 1 shows the results.
• the lubricating oil compositions of Examples 1 to 5 all passed the Timken test, FZG seizure test, FZG micropitting test, and Indiana oxidation test.
• the lubricating oil composition of Example 6 contains no polyol partial ester, and that of Example 7 contains a polyol complete ester. These two compositions give a relatively large amount of sludge in the Indiana oxidation test.
• the lubricating oil composition of Example 8 which contains 2-ethylhexyl (C8 alkyl) acid phosphate as an acidic phosphate ester, gives a slightly large amount of sludge in the Indiana oxidation test.
• the lubricating oil compositions of Comparative Examples 1 to 6 have at least one property falling outside the scope of the present invention. Thus, performance thereof is inferior to that of the compositions of the Examples.
• a commercial product (Comparative Example 7) gives a considerable amount of sludge in the Indiana oxidation test.
• the lubricating oil composition of the present invention has excellent anti-seizure performance, excellent anti-fatigue performance (e.g., anti-FZG-micropitting performance), and reduced sludge formation in an oxidation test, and is suitably used as a lubricating oil such as gear oil or bearing oil.
• the composition is particularly suitable as a lubricating oil for use with a step-up gear (e.g., planetary gear-type power transmission apparatus) in a wind power generator.

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• 2007
  • 2007-09-27 ES ES07828525T patent/ES2384584T3/es active Active
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