Classifications

• • 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
  • C10M163/00—Lubricating compositions characterised by the additive being a mixture of a compound of unknown or incompletely defined constitution and a non-macromolecular compound, each of these compounds being essential
• • 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
  • 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
• • 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
  • C10M2207/00—Organic non-macromolecular hydrocarbon compounds containing hydrogen, carbon and oxygen as ingredients in lubricant compositions
  • C10M2207/26—Overbased carboxylic acid salts
• • 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
  • C10M2207/00—Organic non-macromolecular hydrocarbon compounds containing hydrogen, carbon and oxygen as ingredients in lubricant compositions
  • C10M2207/26—Overbased carboxylic acid salts
  • C10M2207/262—Overbased carboxylic acid salts derived from hydroxy substituted aromatic acids, e.g. salicylates
• • 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
  • C10M2215/00—Organic non-macromolecular compounds containing nitrogen as ingredients in lubricant Compositions
  • C10M2215/24—Organic non-macromolecular compounds containing nitrogen as ingredients in lubricant Compositions having hydrocarbon substituents containing thirty or more carbon atoms, e.g. nitrogen derivatives of substituted succinic acid
  • C10M2215/28—Amides; Imides
• • 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
  • C10M2223/045—Metal containing thio derivatives
• • 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
  • C10N2030/08—Resistance to extreme temperature
• • 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
  • C10N2030/00—Specified physical or chemical properties which is improved by the additive characterising the lubricating composition, e.g. multifunctional additives
  • C10N2030/40—Low content or no content compositions
  • C10N2030/42—Phosphor free or low phosphor content compositions
• • 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
  • C10N2030/52—Base number [TBN]
• • 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
  • C10N2040/25—Internal-combustion engines
  • C10N2040/252—Diesel engines

Definitions

• the present invention relates to a lubricating oil composition. More particularly, the present invention relates to a lubricating oil composition having improved oxidation stability at high temperatures when employed in an internal combustion engines.
• Diesel engines particularly four stroke trunk piston diesel engines, are generally employed as internal combustion engines for generation of electric power and operation of marine vessels. These internal combustion engines are operated smoothly using a lubricating oil composition which contains various additives.
• metal-containing detergents Specifically, an over-based metal-containing detergent which neutralizes sulfur oxide produced by the combustion of fuel and disperses combustion deposits such as sludge is generally employed. Particularly, a lubricating oil composition for marine diesel engines which is operated using high sulfur content fuel such as A-heavy oil or C-heavy oil should contain over-based metal-containing detergents. Most metal-containing detergents are alkaline earth metal sulfonates, alkaline earth metal phenates, and alkaline earth metal salicylates. An ashless dispersant such as succinimide is also generally employed. Examples of other generally employable additives include a zinc dialkyldithiophosphate compound which serves as an anti-oxidation agent and an extreme-pressure agent and an organic anti-oxidation agent such as phenol compound and amine compound.
• the lubricating oil is consumed during the operation of engines. Although a fresh lubricating oil is supplemented periodically to compensate the consumed portion, the amount of sulfur oxide compounds:and combustion residues produced and deposited in the remaining lubricating oil increases. Therefore, after the engine is operated continuously for a long period of time, the lubricating oil suffers from deterioration and viscosity increase.
• Japanese Provisional Patent Publication 2000-63867, U.S. Patent 6,262,001 B1 and Japanese Provisional Patent Publication 2000-87066 disclose a metal-containing overbased calcium carboxylate (i.e., overbased calcium hydrocarbyl-salicylate carboxylate) having high thermal stability and high detergency. It can be prepared with low production costs. These publications describe a variety of compositions for engine lubricating oils.
• the present invention relates to a lubricating oil composition having high thermal oxidation stability at high temperatures which are favorably employable for lubricating various internal combustion engines such as diesel engines and gasoline engines.
• the lubricating oil composition of the present invention is very favorably employed in four stroke trunk piston diesel engines.
• the present invention relates to a lubricating oil composition having a TBN in the range of 5 to 55 mg KOH/g comprising a base oil of lubricating viscosity and
• the present invention relates to a method of improving the oxidation stability at high temperatures of an internal combustion engine, particularly a four stroke trunk piston diesel engine, by operating the internal combustion engine with the lubricating oil composition of the present invention.
• the present invention is based on the surprising discovery that a certain lubricating oil composition provides improved high temperature oxidation stability when employed in internal combustion engines such as diesel engines and gasoline engines.
• the present invention relates to a lubricating oil composition having a major amount of base oil of lubricating viscosity and an overbased calcium carboxylate, bis-succinimide compound and a zinc dialkylthidiophosphate, wherein the TBN of the lubricating oil composition is in the range of 5 to 55 mg KOH/g.
• the base oil of lubricating viscosity employed in the lubricating oil composition of the present invention generally is a mineral oil or a synthetic oil having a dynamic viscosity in the range of 22 to 300 mm 2 /s at 40°C.
• the sulfur content of the base oil is preferably not less than 0.1 wt %, more preferably less than 0.03 wt %, most preferably less than 0.005 wt %.
• the mineral oil is preferably prepared by processing a mineral oil of lubricating oil distillate by an appropriate combination of solvent purification and hydrogenation processing.
• a mineral oil having been subjected to high hydrogenation processing i.e., hydrogenation cracking
• the above-identified most preferred mineral oil can be a high viscosity index base oil which is prepared by processing synthetic wax by isomerization and hydrogenation cracking.
• the synthetic wax was prepared by mineral slack was (crude wax) or natural gas.
• the synthetic oil can be poly- ⁇ -olefin (polymer prepared from ⁇ -olefin having 3 to 12 carbon atoms), a sebacic acid compound such as dioctyl sebacate, a dialkyl diester prepared from a dibasic acid such as azelaic acid or adipic acid and an alcohol having 4 to 18 carbon atoms, a polyol ester prepared from 1-trimethylolpropane or pentaerythritol and a monobasic acid, or an alkylbenzene having alkyl of 9 to 40 carbon atoms.
• the synthetic oil generally contains no sulfur compound and shows high thermal stability and high heat resistance. Moreover, the synthetic oil produces little soot and carbonaceous deposit. Therefore, the synthetic oil is preferred as the base oil for the lubricating oil composition of the present invention.
• each of the mineral base oil and synthetic base oil can be employed singly. However, if desired, two or more of mineral base oils or two or more of synthetic base oils can be employed in combination. Further, if desired, one or more mineral base oils and one or more synthetic base oils can be employed in combination.
• a major amount of base oil of lubricating viscosity as defined herein comprises 40 wt % or more.
• Preferred amounts of base oil comprise 40 wt % to 97 wt %, preferably greater than 50 wt % to 97 wt %, more preferably 60 wt % to 97 wt % and most preferably 80 wt % to 95 wt % of the lubricating oil composition. (When weight percent is used herein, it is referring to weight percent of the lubricating oil composition unless otherwise specified.)
• the overbased calcium carboxylate employed in the lubricating oil of the present invention has a TBN of 100 mg KOH/g or more and can be prepared in the manner described in the aforementioned references cited in the Background of the Invention.
• the overbased calcium carboxylate will be in the amount of 0.19 to 2.10 wt %, preferably 0.38 to 1.15 wt %, based on the total amount of the lubricating oil composition and expressed in terms of the calcium content.
• a representative example of the overbased calcium carboxylate comprises a relatively large amount (more than 50 wt %) of the following compound A and a relatively small amount (less than 50 wt %) of the following compound B: in which R is an alkyl group having 12 to 28 carbon atoms.
• the lubricating oil composition of the present invention can contain other metal-containing detergents in addition to the overbased calcium carboxylate.
• other metal-containing detergents employable in combination with the overbased calcium carboxylate include sulfurized phenate (e.g., sulfurized calcium phenate), petroleum sulfonates or synthetic sulfonates (e.g., calcium sulfonate), and salicylate (e.g., calcium salicylate).
• the lubricating oil composition of the present invention contains a bis-succinimide compound (i.e., succinimide or its derivatives) in the amount of 0.002 to 0.06 wt %, preferably 0.014 to 0.02 wt %, based on the total amount of the lubricating oil composition and expressed in terms of the nitrogen content.
• the bis-succinimide compound preferably is an alkenylsuccinimide or an alkylsuccinimide derived from a polyolefin compound or its derivatives.
• the bis-succinimide can be prepared, for example, by a reaction between succinic anhydride and a high molecular weight alkenyl or alkyl, followed by further reaction with a polyalkylenepolyamine containing 4 to 10, preferably 5 to 7, nitrogen atoms per molecule.
• the bis-succinimide compound can be prepared by a thermal reaction between a polybutene compound containing 50% or more methylvinylidene structure and maleic anhydride, followed by reaction of the resulting polybutenyl succinic anhydride with a polyalkylenepolyamine containing 4 to 10, preferably 5 to 7, nitrogen atoms per molecule.
• the high molecular weight alkenyl or alkyl group preferably is polybutene having a number-average molecular weight in the range of approximately 900 to 5,000.
• the bis-succinimide can be employed in the form of a modified succinimide which is obtained by reacting succinimide with boric acid, alcohol, aldehyde, ketone, alkylphenol, cyclic carbonate (e.g., ethylene carbonate), or an organic acid.
• a modified succinimide which is obtained by reacting succinimide with boric acid, alcohol, aldehyde, ketone, alkylphenol, cyclic carbonate (e.g., ethylene carbonate), or an organic acid.
• a boron-containing alkenyl- or alkylsuccinimide which is obtained by reaction with boric acid or a boron compound.
• the resulting modified succinimide compound exhibits high thermal stability and high anti-oxidation property.
• the lubricating oil composition of the present invention can contain other ashless dispersants such as nitrogen-containing ashless dispersants (e.g., mono-structure type alkenyl- or alkylsuccinimide, and an alkenylbenzylamine) and/or dispersants containing no nitrogen atoms such as an alkenyl succinic ester in addition to the bis-structure alkenyl or alkyl succinimide.
• nitrogen-containing ashless dispersants e.g., mono-structure type alkenyl- or alkylsuccinimide, and an alkenylbenzylamine
• dispersants containing no nitrogen atoms such as an alkenyl succinic ester in addition to the bis-structure alkenyl or alkyl succinimide.
• the zinc dialkyldithiophosphate employed in the lubrication oil composition of the present invention has a secondary alkyl group and will be in the amount of 0.007 to 0.15 wt %, preferably 0.036 to 0.072 wt %, based on the total amount of the lubricating oil composition and expressed in terms of the phosphorus content.
• the alkyl group preferably contains 3 to 18 carbon atoms. All of the two alkyl groups of the zinc dialkyldithiophosphate can be secondary alkyl groups. Otherwise, a portion (e.g., a relatively small portion such as less than 48 mole %) of the alkyl groups of the zinc dialkyldithiophosphate can be a primary alkyl group.
• the secondary-alkyl type zinc dialkyldithiophosphate can be employed in combination with a zinc dialkyldithiophosphate having a primary alkyl group.
• the former zinc dialkyldithiophosphate is generally employed in an amount of 52 to 98 mole %, and the latter zinc dialkyldithiophosphate can be employed in an amount of 2 to 48 mole %.
• the lubricating oil composition of the present invention can further contain other oxidation inhibitors, such as phenol oxidation inhibitors and/or amine oxidation inhibitors, in an amount of 0.01 to 5wt %, preferably 0.1 to 3 wt %.
• the lubrication oil composition of the present invention can further contain a multi-functional molybdenum-containing compound in an amount of 0.01 to 5 wt %, preferably 0.1 to 3 wt %.
• the molybdenum-containing compound mainly serves as friction-modifier, oxidation inhibitor and anti-wear agent in the lubricating oil composition of the present invention.
• the molybdenum-containing compound further provides effective high temperatures detergency.
• the molybdenum-containing compound can be incorporated into the lubricating oil composition of the present invention in an amount of 10 to 2,500 ppm in terms of the molybdenum metal content.
• molybdenum-containing compounds include, but not limited to, a sulfur-containing molybdenum complex compound of succinimide, sulfurized oxymolybdenum dithiocarbamate, sulfurized oxymolybdenum dithiophosphate, an amine-molybdenum complex compound, oxymolybdenum diethylateamide, and oxymolybdenum monoglyceride.
• the sulfur-containing molybdenum complex compound of succinimide is particularly effective to increase detergency at high temperatures.
• the lubricating oil composition of the present invention can further contain a viscosity index improver in an amount of less than 20 wt %, preferably in an amount of 1 to 20 wt %.
• a viscosity index improver examples include polymers as poly(alkyl methacrylate), ethylene-propylene copolymer, styrenebutadiene copolymer, and polyisoprene.
• Dispersant-type viscosity index improvers and multi-functional viscosity index improvers which are obtained by adding dispersancy to the above-mentioned polymers are also employable.
• the viscosity index improvers can be employed singly or in combination.
• the lubricating oil composition of the present invention can further contain a variety of subsidiary additives.
• the subsidiary additives include, but not limited to, oxidation inhibitors/anti-wear agents (e.g., zinc dithiocarbamate, methylene-bis(dibutyldithiocarbamate), oil-soluble copper compounds, sulfur-containing compounds such as sulfurized olefins, sulfurized esters and polysulfides, phosphate esters, phosphite esters, and organic amide compounds such as oleylamide.
• Metal-deactivating compounds such as benzotriazol compounds and thiaziazol compounds also can be employed.
• Anti-rust agents and de-emulsifiers such as nonionic surfactants (e.g., polyoxyethylene alkylphenyl ether, and copolymer of ethylene oxide and propylene oxide) also can be employed.
• Friction modifiers such as amines, amides, amine salts, their derivatives, and fatty acid esters of polyhydric alcohols and their derivatives also can be employed.
• Anti-foaming agents and pour point depressants also can be employed.
• Each of the subsidiary additives is generally contained in the lubricating oil composition of the present invention in an amount of less than 3 wt %, preferably in the range of 0.001 to 3 wt %.
• a lubricating oil composition (TBN: 30 mg•KOH/g, SAE viscosity grade: SAE 40) was prepared using the following additives and base oil:
• a lubricating oil composition having the same composition of Example 1 except for containing no bis-succinimide (component b) was prepared.
• a lubricating oil composition having the same composition of Example 1 except for replacing the zinc di(secondary)alkyldithiophosphate (component c) with a zinc di(primary)alkyldithiophosphate was prepared.
• the phosphorus content of the latter di(primary)alkyldithiophosphate was the same as that of the former zinc di(secondary)alkyldithiophosphate.
• a lubricating oil composition having the same composition of Example 1 except for replacing the bis-succinimide (component b) with a mono-succinimide dispersant was prepared.
• the thermal stability of the lubrication oil compositions at high temperatures was evaluated using the JIS (Japanese Industrial Standard) K2514 ISOT (Indiana Stirred Oxidation Test). This test is used to determine the oxidation stability of a lubricating oil composition in the presence of copper, steel and heat.
• JIS Japanese Industrial Standard
• K2514 ISOT Indiana Stirred Oxidation Test

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Organic Chemistry (AREA)
• Lubricants (AREA)

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• 2004
  • 2004-12-28 JP JP2004380522A patent/JP5198719B2/ja not_active Expired - Lifetime
• 2005
  • 2005-12-23 CA CA2531433A patent/CA2531433C/en not_active Expired - Fee Related
  • 2005-12-23 EP EP05258039.6A patent/EP1676902B1/de not_active Expired - Lifetime
  • 2005-12-27 SG SG200508401A patent/SG123779A1/en unknown

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