JP2009544767A - Lubricating method for heavy load gear device - Google Patents

Abstract

A method for improving the oil draining interval, fuel and energy efficiency of a heavy load gear mechanism, wherein the base oil is PAO 2 to 10 about 20 to 75 wt%, PAO 150 to 1000 about 5 to 40 wt%, PAO 20 to 100 about 10 An effective amount of at least one gear oil additive, comprising about 5-20 wt% of one or more polyol esters or dibasic acid esters having ˜40 wt%, kinematic viscosity (100 ° C.) of about 2-5 mm ² / sec. A method by lubricating an apparatus with a lubricating oil composition comprising: At that time, the lubricating oil composition has a kinematic viscosity (100 ° C.) of 9 to 12.5 mm ² / sec, a traction coefficient value (100 ° C./30 SSR value) of 0.0197 or less, and a Brookfield viscosity (−40 ° C.) about 26,000 or less and CCS viscosity (−25 ° C.) of 4200 cP or less, flash point of 220 ° C. or more, and NOACK volatility of 15% or less.
[Selection figure] None

Description

  The present invention relates to power transmission fluids or gear oils, and to methods for improving the energy efficiency of heavy duty gear mechanisms / devices by using lubricating oils with enhanced performance efficiency.

  Heavy duty gear mechanisms (manual transmissions, automatic transmissions, actuators, gearboxes, etc.) that operate at high temperatures and high loads for extended periods of time are not properly lubricated using current lubricant formulations. This does not give the proper film thickness and results in metal-to-metal contact (boundary lubrication).

  Similar gear equipment manufacturers have demanded that the lubricants used to lubricate newer design equipment meet more stringent low temperature performance requirements due to Brookfield viscosity and cold cranking simulation (CCS) viscosity. ing.

Patent Document 1 relates to a motor vehicle transmission fluids, which has a kinematic viscosity (100 ° C.) 1 to 10 mm ² / s natural mineral oil 50 wt% or more with a kinematic viscosity (100 ° C.) 1 to 10 mm synthetic lubricating with ² / sec Contains 1 to 25 wt% of high viscosity polyalphaolefin having an oil of 49 wt% or less and a kinematic viscosity (100 ° C.) of 40 to 500 mm ² / sec.

Patent Document 1 describes that a synthetic lubricating oil having a kinematic viscosity (100 ° C.) of 1 to 10 mm ² / sec can be selected from hydrocarbon oils and halogen-substituted hydrocarbon oils. Oligomerized, polymerized and copolymerized olefins (eg polybutene, polypropylene, propylene-isobutylene copolymer, chlorinated polyaceten, poly (1-hexene), poly (1-octene), poly ( 1-decene) and the like, and mixtures thereof); alkylbenzenes; polyphenyls; alkylated diphenyl ethers; alkylated diphenyl sulfides, etc., preferably polyalphaolefins. Further synthetic lubricating oils include alkylene oxide polymers, interpolymers, copolymers, and derivatives thereof; dicarboxylic acids (eg, phthalic acid, succinic acid, alkyl succinic acid, alkenyl succinic acid, maleic acid, azelaic acid, suberic acid, Sebacic acid, fumaric acid, adipic acid, linolenic acid dimer, malonic acid, alkylmalonic acid, alkenylmalonic acid, etc.) and various alcohols (eg, butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl alcohol, ethylene) And diesters which are esters with glycol, diethylene glycol, monoether, propylene glycol and the like). In particular, dibutyl adipate, di (2-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate, dieicosyl sebacate, linolenic acid Dimeric 2-ethylhexyl diesters, preferably adipates of C _{4 to} C ₁₂ alcohols. Other useful synthetic lubricating oils, C ₅ -C ₁₂ monocarboxylic acids and polyols - include those made from the LE and / or polyol ester. Neopentyl glycol, trimethylolpropane, pentaerythritol and the like.

In general, preferred synthetic oils are polyalphaolefins, diesters, and polyol esters, which are described to have a kinematic viscosity (100 ° C.) of 2-8 mm ² / sec, preferably 3-5 mm ² / sec.

Patent document 2 is related with an energy-saving power transmission fluid. This is 1 to 49 wt% of a polyalphaolefin base material having a kinematic viscosity (100 ° C) of 40 to 500 mm ² / sec, 1 to 95 wt% of a lubricant base material having a kinematic viscosity (100 ° C) of ^{2 to} 10 mm ² / sec, 1 to 49 wt% polyol ester of a C _{5 to} C ₃₀ aliphatic monocarboxylic acid and a polyol of formula R (OH) _n where n is at least 2, and an effective amount of performance additive package The power transmission fluid composition has a kinematic viscosity (100 ° C.) of at least 4 mm ² / sec.

The lubricating oil base can be a mineral oil or a synthetic lubricating oil, preferably a polyalphaolefin or mineral oil. No viscosity range is given for polyol esters, but the only one exemplified is Priolube 3999 from Uniquema (Gouda, The Netherlands), which has a kinematic viscosity (100 ° C.) of 13.19 mm ² / sec.

Patent Document 3, kinematic viscosity (100 ° C.) of about 2 to 10 mm ² / sec major amount of polyalphaolefin fluid having, and kinematic viscosity (100 ° C.) a small amount of polyalphaolefin fluid having about 40~120mm ² / sec And an anti-wear / extreme pressure agent (selected from phospho-dispersants, phosphorus- and boron-containing ashless dispersants). The composition does not contain any metal-containing components and has a kinematic viscosity (100 ° C.) of at least 5.5 mm ² / sec, a Brookfield viscosity (−40 ° C.) less than 20,000 cP, or a kinematic viscosity (100 ° C.) Characterized as having at least 6.8 mm ² / sec and a Brookfield viscosity (−40 ° C.) of less than 50,000 cP.

The formulation can also include synthetic esters. Mixed C ₉ and C ₁₁ dialkyl phthalate, trimethylolpropane trioleate, di - isotridecyl - adipate, pentaerythritol tetra heptanoate, and the like. Examples include PAO6, PAO8, PAO110, and diisononyl adipate, dioctyl sebacate, dibutyl phthalate, or di (tridecyl) phthalate with performance additives.

Patent Document 4 relates to an automatic transmission fluid. This kinematic viscosity (100 ° C.) to about 2~10mm polyalphaolefin 70% to 99% with ² / sec, and kinematic viscosity (100 ° C.) to about 40~120mm polyalphaolefin 30～1Wt percent having ² / sec Contains a complete base oil and further contains 1-15 wt% antiwear / extreme pressure agent, other performance additives, and no more than 10 wt% viscosity index improver, and is substantially free of metal-containing components. The fluid has a KV (100 ° C.) of at least 5.5 mm ² / sec and a Brookfield viscosity (−40 ° C.) of less than 20,000 cP, or a KV (100 ° C.) of at least 6.8 mm ² / sec, and Brook Field viscosity (−40 ° C.) less than 50,000 cP. The fluid can also include a synthetic ester. Mixed C ₉ and C ₁₁ dialkyl phthalates, trimethylol propane trioleate, di (isotridecyl) adipate, pentaerythritol tetraheptanoate and the like. Examples include PAO6 and / or PAO8, and mixtures of PAO110 when diisononyl adipate, di (tridecyl) adipate, synthetic esters (Hatcol 2923, Hatcol 2920, Hatcol 2915, Hatcol 2970, dioctyl sebacate, dibutyl phthalate, dioctyl sebacate , Identified as Emery 2935, Emery 2939).

Patent Document 5 relates to a high-performance engine oil and other liquid lubricants. This is selected from mineral oil, polyalphaolefin, hydroisomerized Fischer-Tropsch wax and about 50-90 wt% base oil having a KV (100 ° C.) of 1.5-12 mm ² / sec, first polymer about 0 0.1 to about 20 wt% and a second polymer from about 0.1 to about 5 wt%. The first polymer is a polyalphaolefin having a lower molecular weight than the second polymer and having a viscosity of 20 to 3000 mm ² / sec, the second polymer has a molecular weight of at least 100,000 and is thickened Has characteristics. In the example, PAO (1.7mm ² / s (100 ℃)), PAO ( 4mm 2 / sec (100 ℃)), PAO ( 5.6mm 2 / s (100 ℃)), and PAO (150 mm ² / Various mixtures of seconds (100 ° C.) are prepared and formulated with unidentified “esters”. Low molecular weight components can also include esters (generally identified as having a kinematic viscosity (100 ° C.) of 1.5 to 12 mm ² / sec). Esters are derived from dibasic acids reacted with monoalcohols and polyol esters of monocarboxylic acids. Useful esters include dicarboxylic acids (phthalic acid, succinic acid, alkyl succinic acid, alkenyl succinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, linolenic acid dimer, malonic acid, And esters of various alcohols (such as butyl, hexyl, dodecyl, and 2-ethylhexyl alcohol). Specific esters include dibutyl adipate, di (2-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate, dilicosyl Sebacate etc. are included.

Useful polyol esters include one or more polyhydric alcohols, preferably hindered polyols (such as neopentyl polyol, such as neopentyl glycol, trimethylol ethane, trimethylol propane, 2-methyl-2-propyl-1, 3-propanediol, pentaerythritol, and dipentaerythritol) include those produced by reacting with the carbon atoms at least 4 alkanoic acids containing (usually the C ₅ -C ₃₀ acids). Examples of these polyol esters are the Mobil P-41 and Mobil P-51 esters (Mobil Chemical Company).

Patent Document 6 relates to a VI-enhanced lubricating oil additive and a lubricating oil composition. The additive comprises an olefin oligomer having a number average molecular weight of about 2,000 to 20,000 and a viscosity (100 ° C.) of about 75 to 3,000 mm ² / sec, and a hydrocarbyl aromatic (its weight from the aromatic portion of at least about 5 wt% And has a viscosity (100 ° C.) of about 3 to 50 mm ² / second). Lubricating oils are described including this additive. These lubricating oils include base oils that can be mineral oils, synthetic oils, or mixtures thereof. Synthetic oils include PAOs and esters, as well as other possible synthetic materials. In the example, the olefin oligomer is a polymer of decene-1 (having a viscosity (100 ° C.) of about 150 mm ² / sec), which is PAO4, mineral oil, and unidentified ester (KV (100 ° C.) 5.5 mm). ² / sec, with VI 131). See Examples 4.2, 4.4, and 4.6.

  Patent document 7 is related with the lubricating fluid of a motor vehicle gear. The finishing fluid has a viscosity index of 175 or higher.

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"Lubricating oils and related products" by Klamann C. V. Smallheer and R.A. K. “Lubricant Additives” by Smith (Lezius-Hiles Co., Cleveland, Ohio, 1967)

The fluid comprises a high viscosity fluid, preferably a polyalphaolefin. This is blended with a lower viscosity fluid containing synthetic hydrocarbons (which can also be polyalphaolefins). The high viscosity fluid has a KV (100 ° C.) of 40-3000 mm ² / sec, while the lower viscosity fluid has a KV (100 ° C.) of 40 mm ² / sec or less. The formulation also includes esters and mineral oils and one or more performance additives. Additive mixture, lower viscosity hydrocarbon fluid PAO-2 (SHF ™ 23), lower viscosity ester (Esterex ™ M11), Supersyn ™ 2150 (PAO-150); additive, PAO Examples of -25 (SHF ™ 23), Esterex ™ M11, SHF ™ 1003 (PAO-100) (high viscosity hydrocarbon fluid), and Supersyn ™ 2300 (PAO300) are shown. Esterex ™ M11 is a commercially available ester and has a kinematic viscosity (100 ° C.) of about 1.25 to 1.45 mm ² / sec.

  The oil drain interval, fuel and energy efficiency of the heavy load gear mechanism is determined by the lubricant formulation useful for these gear heavy load mechanisms (in use, traction coefficient, Brookfield viscosity (−40 ° C.) less than about 21,000 cP and CCS It would be advantageous to increase by identifying (−25 ° C.) showing an improvement of about 3800 cP or less.

Methods have been discovered to improve the fuel and energy efficiency of heavy load gear mechanisms under high load conditions by lubricating the heavy load gear mechanism with a lubricating oil composition. At that time, the lubricating oil composition has a kinematic viscosity (100 ° C.) (ASTM D-445-5) of about ^{2 to} 10 mm ² / sec (preferably about 3.5 to 8 mm ² / sec, most preferably 3.5 to 6 mm ² / sec) polyalphaolefin fluid about 20～75Wt% with (preferably about 30 to about 60 wt%, more preferably about 45~55wt%), kinematic viscosity (100 ℃) (ASTM D- 445-5) about 150~3000mm ² / s (preferably about 150~1500mm ² / sec, more preferably about 150~1000mm ² / sec, even more preferably about 150~500mm ² / sec, most preferably about 150 to 300 mm ² / Polyalphaolefin fluid having a second) of about 5-40 wt% (preferably about 5-20 wt%, more preferably about 8-12 wt%), kinematic viscosity (10 ℃) (ASTM D-445-5) about 20 to 100 mm ² / s (preferably about 20 to 80 mm ² / sec, more preferably about 20 to 60 mm ² / sec, and most preferably about 40-60 mm ² / s) Polyalphaolefin fluid having about 10-40 wt% (preferably about 15-30 wt%, more preferably about 18-22 wt%), kinematic viscosity (100 ° C.) about 2-5 mm ² / sec (preferably about 2-4 A polybasic acid having a 0.5 mm ² / sec, more preferably about 2.5-4.5 mm ² / sec) and a pour point of at least −25 ° C. (preferably at least −25 ° C., more preferably at least −45 ° C.). Or an ester of a mono-alkanol or a mixture of a monoalkanol and a polyalkanol, preferably a polyol ester About 5 to 20 wt% (preferably about 5 to 15 wt%, more preferably about 8 to 12 wt%), more preferably an ester of a dibasic acid and a monoalkanol, most preferably an adipic ester, At least one gear oil additive. The lubricating oil ^{composition, KV (100 ℃) 9~12.5mm 2} / sec (preferably 10-12 mm ² / s) has (measured as 100 ℃ / 30SSR value) traction coefficient value of about 0 0.0197 or less (preferably about 0.0191 or less), Brookfield viscosity (−40 ° C.) about 26,000 cP or less (preferably about 21,000 cP or less), and CCS viscosity (−25 ° C.) about 4200 cP or less (preferably About 3,600 cP or less, more preferably about 3400 cP or less). All wt% is based on the total weight of the lubricating oil composition.

  In the present invention, the base oil comprises a specific combination of polyalphaolefin base oils in combination with one or more of the listed esters to produce a formulation that exhibits unexpectedly enhanced performance characteristics.

Polyalphaolefin (PAO) is a hydrocarbon base oil well known in the lubricating oil industry. PAO is derived from the polymerization or copolymerization of alpha olefins having 2 to 32 carbons. More typically, C ₈ , C ₁₀ , C ₁₂ , C ₁₄ olefins, or mixtures thereof are used.

PAO is a known substance and is generally available on a commercial scale from suppliers such as ExxonMobil Chemical Company, Chevron-Phillips, BP-Amoco, Albemarl Corporation, etc., but its number average molecular weight is typically May have a viscosity (100 ° C.) of from about 2 to about 3000 mm ² / sec.

PAO typically comprises a relatively low molecular weight hydrogenated polymer or oligomer of an alpha olefin, which includes, but is not limited to, about C ₂ to about C ₃₂ alpha olefin. - octene, 1-decene, from about _{C 8} ~ about _{C 16} alpha olefins such as 1-dodecene are preferred. Preferred polyalphaolefins are poly-1-octene, poly-1-decene, poly-1-dodecene, and mixtures thereof, and mixed olefin derived polyolefins. However, dimers of higher olefins of about C _{14 to} C ₁₈ may be used to provide an acceptably low volatility low viscosity substrate. Depending on the viscosity grade and starting oligomers, the PAO is primarily the trimers and tetramers of the starting olefin, and may have a small amount of higher oligomers.

The PAO fluid may be conveniently made by polymerizing alpha olefins in the presence of a polymerization catalyst such as a Friedel-Crafts catalyst. Examples include complexes of aluminum trichloride, boron trifluoride, or boron trifluoride with water, alcohols (such as ethanol, propanol, or butanol), carboxylic acids, or esters (such as ethyl acetate or ethyl propionate). For example, the methods disclosed in US Pat. Other descriptions of PAO synthesis are as follows: Patent Document 10, Patent Document 11, Patent Document 12, Patent Document 13, Patent Document 14, Patent Document 15, Patent Document 16, Patent Document 17, Patent Document 18, Patent Document 19, It can be found in Patent Document 20 and Patent Document 21. Dimers of C ₁₄ -C ₁₈ olefins are described in US Pat.

High viscosity PAOs suitable for the present invention may be prepared by reaction of a reduced chromium catalyst with an alpha olefin. These PAOs are described in Patent Document 18 (Wu), Patent Document 17 (Wu), Patent Document 23 (Ho et al), Patent Document 24 (Pelline et al), and Patent Document 25 (Pelline). Dimers of C ₁₄ -C ₁₈ olefins are described in US Pat. Commercially available high viscosity PAOs include SuperSyn ™ 2150, SuperSyn ™ 2300, SuperSyn ™ 21000, SuperSyn ™ 23000 (ExxonMobil Chemical Company).

  In the present invention, the lubricating oil comprises a base oil consisting of a specific mixture of PAOs of different viscosities, and further comprises an ester and at least one performance additive.

The lubricant formula is
(A) PAO having a kinematic viscosity (100 ° C.) of about ^{2 to} 10 mm ² / sec (preferably about 3.5 to 8 mm ² / sec, most preferably about 3.5 to ⁶ mm ² / sec) about 20 to 75 wt% (Preferably about 30 to about 60 wt%, more preferably about 45 to 55 wt%), (b) kinematic viscosity (100 ° C.) about 150 to 3,000 mm ² / sec (preferably about 150 to 1500 mm ² / sec, more Preferably about 150 to 1000 mm ² / sec, even more preferably about 150 to 500 mm ² / sec, most preferably about 150 to 300 mm ² / sec) PAO about 5 to 40 wt% (preferably about 5 to about 20 wt%) , More preferably about 8-12 wt%),
(C) a kinematic viscosity (100 ° C.) of about 20 to 100 mm ² / s (preferably about 20 to 80 mm ² / sec, more preferably about 20 to 60 mm ² / sec, and most preferably about 40-60 mm ² / second) PAO having about 10-40 wt% (preferably about 15-30 wt%, more preferably about 18-22 wt%),
(D) polyol ester, ester of monobasic (or polybasic acid) and monoalkanol (or mixture of monoalkanol and polyalkanol) (preferably non-polyol ester, more preferably ester of dibasic acid and monoalkanol, Most preferably selected from esters of adipic acid) and kinematic viscosity (100 ° C.) of about 2-5 mm ² / sec (preferably about 2-4.5 mm ² / sec, more preferably about 2.5-4.5 mm ² About 5 to 20 wt.% (Preferably about 5 to 15 wt.%, More preferably about 8 to 12 wt.%) Of one or more esters having (e / sec), and (e) and at least one gear oil performance additive. Including. The lubricating oil ^{composition, KV (100 ℃) 9~12.5mm 2} / sec (preferably 10-12 mm ² / s) has (measured as 100 ℃ / 30SSR value) traction coefficient value of about 0 0.0197 or less (preferably about 0.0195 or less), Brookfield viscosity (−40 ° C.) of about 26,000 cP or less (preferably about 21,000 cP or less) and CCS viscosity (−25 ° C.) of about 4200 cP or less (preferably about 3,600 cP or less, more preferably about 3,400 cP or less), NOACK volatility of 15% or less (preferably 13% or less), and flash point of 220 ° C. or higher (preferably 230 ° C. or higher). All wt% is based on the total lubricating oil composition.

  In this specification and the appended claims, kinematic viscosity is determined by the ASTM D-445-5 test method and Brookfield viscosity (−40 ° C.) is determined by ASTM D-2983-31 as Ranking simulation (CCS) viscosity (−25 ° C.) is ASTM D-5293-5, NOACK volatility is ASTM D-5800, flash point is ASTM D-97, and traction coefficient is 16 N / 100. According to ° C / 30 SSR.

  The formulation is further characterized by the absence of a viscosity index improver whose presence is detrimental to the traction coefficient.

  Esters of mono- and polybasic (especially dibasic) acids and monoalkanols are dicarboxylic acids (phthalic acid, succinic acid, alkyl succinic acid, alkenyl succinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid , Esters of adipic acid, linoleic acid dimer, malonic acid, alkylmalonic acid, alkenylmalonic acid, etc.) and various alcohols (butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl alcohol, etc.) And esters of polyalkanols. Specific examples of these types of esters include nonyl heptanoate, dibutyl adipate, di (2-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, Dioctyl phthalate, didecyl phthalate, dieicosyl sebacate and the like are included.

Other useful synthetic esters include one or more polyhydric alcohols (preferably hindered polyols such as neopentyl polyol, such as neopentyl glycol, trimethylol ethane, 2-methyl-2-propyl-1,3- propanediol, trimethylolpropane, pentaerythritol, and dipentaerythritol tri Torr), alkanoic acids (preferably C ₅ -C ₃₀ acid containing at least about 4 carbon atoms; caprylic acid, capric acid, lauric acid, myristic acid, palmitic Acid, stearic acid, arachidic acid, and saturated straight chain fatty acids including behenic acid or corresponding branched chain fatty acids or unsaturated fatty acids such as oleic acid).

  Suitable synthetic ester components include trimethylolpropane, trimethylolbutane, trimethylolethane, pentaerythritol and / or dipentaerythritol and one or more monocarboxylic acids (containing from about 5 to about 10 carbon atoms) and Of esters.

  A preferred ester is an ester of a dibasic acid and a monoalkanol.

  The gear oil formulation includes an effective amount of at least one gear oil performance additive. By effective amount is meant a small amount sufficient for the additive to provide the desired performance improving effect, based on the total weight of the formulated lubricant. The effective amount is usually about 20 wt% or less, preferably about 3 to 12 wt%, more preferably about 4 to 7 wt%, based on the total amount of at least one (ie, one or more) performance additives.

  In order to achieve the desired lubricating oil performance, suitable performance additives for use in the present gear oil include antioxidants, antiwear agents, metal corrosion inhibitors, friction modifiers, ashless dispersants, detergents, and dissipators. It is a foaming agent and a seal swelling agent. It should be noted that the gear oil formulation does not include a viscosity modifier or viscosity index improver.

Antiwear and EP Agents Many lubricants require the presence of antiwear and / or extreme pressure (EP) agents to provide adequate wear resistance. For example, increasingly stringent standards for engine oil performance indicate a tendency to improve the wear resistance properties of the oil. Antiwear and extreme pressure EP agents serve this role by reducing friction and wear of metal parts, brass protection, heat stable wear, scuffing, and surface fatigue.

Although there are many different types of antiwear agents, for decades, the main antiwear agent for crankcase oils of internal combustion engines has been metal alkylthiophosphates, more specifically metal dialkyldithiophosphates (its main The metal component is zinc) or zinc dialkyldithiophosphate (ZDDP). The ZDDP compound is generally of the formula Zn [SP (S) (OR ¹ ) (OR ² )] ₂ . In the formula, R ¹ and R ² are C _{1 to} C ₁₈ alkyl groups, preferably C _{2 to} C ₁₂ alkyl groups. These alkyl groups may be straight chain or branched. ZDDP is typically more or less the amount of phosphorus and zinc that can be attributed to ZDDP (P approximately 420-1500 ppm and Zn 450-1600 ppm), although it can often be used conveniently, It is used in an amount of about 0.4-6 wt% of the product, preferably about 0.8-4.0 wt%.

Various non-phosphorous additives are also used as antiwear agents. Sulfurized olefins are useful as antiwear and EP agents. Sulfur-containing olefins are obtained by sulfiding various organic materials, including aliphatic, arylaliphatic, or cycloaliphatic olefinic hydrocarbons containing about 3 to 30 carbon atoms, preferably 3 to 20 carbon atoms. Can be prepared. The olefinic compound contains at least one non-aromatic double bond. These compounds are
R ³ R ⁴ C = CR ⁵ R ⁶
Defined by

In the formula, each of R ^{3 to} R ⁶ is independently hydrogen or a hydrocarbon group. Preferred hydrocarbon groups are alkyl or alkenyl groups. Any two of R ^{3 to} R ⁶ may be combined to form a ring. Further information regarding sulfurized olefins and their preparation can be found in US Pat.

The use of thiophosphoric acid and polysulfide of thiophosphoric acid ester as a lubricant additive is disclosed in Patent Document 27, Patent Document 28, Patent Document 29, and Patent Document 30. The addition of phosphorothionyl disulfide as an antiwear agent, antioxidant, and EP agent is disclosed in US Pat. Wear resistance of lubricating oils by combining alkylthiocarbamoyl compounds (eg bis (dibutyl) thiocarbamoyl) with molybdenum compounds (eg oxymolybdenum diisopropyl phosphorodithioate sulfide) and phosphorous esters (eg dibutyl hydrogen phosphite) Use as an agent is disclosed in Patent Document 32. U.S. Patent No. 6,057,836 discloses that carbamate additives are used to provide improved antiwear and extreme pressure properties. The use of thiocarbamate as an antiwear agent is disclosed in US Pat. Molybdenum - thiocarbamate / molybdenum complexes such as sulfur alkyl dithiocarbamate trimer complex (R = C ₈ ~C ₁₈ alkyl) are also useful antiwear agents. The use or addition of these materials should be kept to a minimum if the objective is to produce a low SAP formulation.

  Glycerol esters may be used as antiwear agents. For example, mono-, di-, and tri-oleate, mono-palmitate, and mono-myristate may be used.

  ZDDP can be combined with other compositions that provide antiwear properties. Patent Document 35 discloses that a combination of a thiodixanthogen compound (for example, octylthiodixanthogen) and a metal thiophosphate (for example, ZDDP) can improve wear resistance. In Patent Document 36, wear resistance characteristics are improved by using a metal alkoxyalkylxanthate (for example, nickel ethoxyethylxanthate) and a dixanthogen (for example, diethoxyethyldixanthogen) in combination with ZDDP. Is disclosed.

  Preferred antiwear agents include phosphorus and sulfur compounds. Zinc dithiophosphate and / or sulfur, nitrogen, boron, molybdenum phosphorodithioate; molybdenum dithiocarbamate; and various organomolybdenum derivatives including heterocycles such as dimercaptothiadiazole, mercaptobenzothiadiazole, triazine, and the like. , Amines, alcohols, esters, diols, triols, fatty acid amides, etc. can also be used These additives are used in an amount of about 0.01-6 wt%, preferably about 0.01-4 wt%. ZDDP-like compounds provide limited hydroperoxide degradation function (substantially lower than that shown by the compounds disclosed and claimed in this patent) and are therefore excluded from the formulation Or even if kept low It can be held at a minimum concentration in order to promote the production of AP formulation.

Antioxidants Antioxidants inhibit oxidative degradation of base oils during use. These degradations may result in metal surface deposits, the presence of sludge in the lubricating oil, or an increase in its viscosity. Those skilled in the art are aware of a wide variety of antioxidants useful in lubricating oil compositions. For example, see Non-Patent Document 1 (supra), Patent Document 37, and Patent Document 38.

Useful antioxidants include hindered phenols. These phenolic antioxidants may be ashless (metal-free) phenolic compounds or neutral or basic metal salts of certain phenolic compounds. A typical phenolic antioxidant compound is a hindered phenol that contains a sterically hindered hydroxyl group. These include derivatives of dihydroxyaryl compounds (hydroxyl groups in the o- or p-position relative to each other). Typical phenolic antioxidants include hindered phenols substituted with C ₆ ⁺ alkyl groups, and alkylene-linked derivatives of these hindered phenols. Examples of this type of phenolic material are 2-t-butyl-4-heptylphenol; 2-t-butyl-4-octylphenol; 2-t-butyl-4-dodecylphenol; 2,6-di-t-butyl. 2,6-di-tert-butyl-4-dodecylphenol; 2-methyl-6-tert-butyl-4-heptylphenol; and 2-methyl-6-tert-butyl-4-dodecyl Phenol. Other useful hindered mono-phenol antioxidants may include, for example, hindered 2,6-di-alkyl-phenol propionic acid ester derivatives. Bis-phenol antioxidants may also be advantageously used in combination with the present invention. Examples of ortho-linked phenols include 2,2′-bis (4-heptyl-6-tert-butyl-phenol); 2,2′-bis (4-octyl-6-tert-butyl-phenol); and 2,2′-bis (4-dodecyl-6-tert-butyl-phenol) is included. Para-linked bisphenols include, for example, 4,4′-bis (2,6-di-t-butylphenol) and 4,4′-methylene-bis (2,6-di-t-butylphenol).

Non-phenolic antioxidants that may be used include aromatic amine antioxidants. These may be used either on their own or in combination with phenols. Typical examples of non-phenolic antioxidants include the formula R ⁸ R ⁹ R ¹⁰ N where R ⁸ is an aliphatic, aromatic, or substituted aromatic group and R ⁹ is aromatic or A substituted aromatic group, wherein R ¹⁰ is an alkylated and non-alkylated aromatic amine such as an aromatic monoamine of H, alkyl, aryl), or R ¹¹ S (O) _X R ¹² , wherein R ¹¹ is An alkylene, alkenylene, or aralkylene group, R ¹² is a higher alkyl group, or an alkenyl, aryl, or alkaryl group, and x is 0, 1, or 2. The aliphatic group R ⁸ may contain 1 to about 20 carbon atoms, and preferably contains about 6 to 12 carbon atoms. An aliphatic group is a saturated aliphatic group. Preferably, both R ⁸ and R ⁹ are aromatic or substituted aromatic groups, and the aromatic group may be a condensed ring aromatic group such as naphthyl. Aromatic groups R ⁸ and R ⁹ may be joined together by other groups such as S.

  Typical aromatic amine antioxidants have an alkyl substituent of at least about 6 carbon atoms. Examples of aliphatic groups include hexyl, heptyl, octyl, nonyl, and decyl. In general, an aliphatic group will not contain more than about 14 carbon atoms. Common types of amine antioxidants useful in the present compositions include diphenylamine, phenylnaphthylamine, phenothiazine, imidodibenzyl, and diphenylphenylenediamine. Mixtures of two or more aromatic amines are also useful. Polymeric amine antioxidants can also be used. The polymeric aromatic amine antioxidants include polymeric diphenylamine antioxidants, polymeric phenylnaphthyleneamine antioxidants, and polymeric diphenylamine / phenylnaphthaleneamine antioxidants. Specific examples of aromatic amine antioxidants useful in the present invention include p, p'-dioctyldiphenylamine, t-octylphenyl-alpha-naphthylamine, phenyl-alphanaphthylamine, and p-octylphenyl-alpha-naphthylamine. included.

  Sulfurized alkylphenols, their alkali or alkaline earth metal salts, alkyl aromatic sulfides, phosphorus compounds (such as phosphites and phosphonates), sulfur-phosphorus compounds (such as dithiophosphates), and other types (such as dialkyldithiocarbamates), As well as mixtures thereof are also useful antioxidants.

  Another type of antioxidant used in lubricating oil compositions is oil-soluble copper compounds. Any oil soluble suitable copper compound may be blended into the lubricating oil. Examples of suitable copper antioxidants include copper dihydrocarbylthio- or dithio-phosphate, and copper salts of carboxylic acids (natural or synthetic). Other suitable copper salts include copper dithiacarbamate, sulfonate, phenate, and acetylacetonate. Basic, neutral, or acidic copper Cu (I) and / or Cu (II) salts derived from alkenyl succinic acids or anhydrides are known to be particularly useful.

  Preferred antioxidants include hindered phenols and arylamines. These antioxidants may be used individually or in combination with each other. These additives may be used in an amount of about 0.01 to 5 wt%, preferably about 0.01 to 1.5 wt%.

Detergents Detergents are usually used in lubricating compositions. A typical detergent is an anionic material. This includes the long-chain hydrophobic portion of the molecule and the smaller anionic or oleophobic hydrophilic portion of the molecule. The anionic portion of the detergent is typically derived from an organic acid such as sulfuric acid, carboxylic acid, phosphoric acid, phenol, or mixtures thereof. The counter ion is typically an alkaline earth or alkali metal.

  A salt containing a substantially theoretical amount of metal is described as a neutral salt. It has a total base number (TBN; measured by ASTM D2896) of 0-80. Many compositions are overbased and contain large amounts of metal bases. This is accomplished by reacting an excess of a metal compound (eg, a metal hydroxide or oxide) with an acidic gas (such as carbon dioxide). Useful detergents can be neutral, mildly overbased, or highly overbased.

  Desirably, at least some detergents are overbased. Overbased detergents help neutralize acidic impurities introduced by the combustion process and be incorporated into the oil. Typically, the overbased material has a (metal ion) / (anionic portion of detergent) ratio of about 1.05: 1 to 50: 1 on an equivalent basis. More preferably, the ratio is from about 4: 1 to about 25: 1. The resulting detergent is an overbased detergent that will typically have a TBN of about 150 or more, often about 250 to 450 or more. Preferably, the overbasing cation is sodium, calcium, or magnesium. Mixtures of different TBN detergents can be used in the present invention.

  Preferred detergents include sulfonates, phenates, carboxylates, phosphates, and alkali or alkaline earth metal salts of salicylates.

  Sulfonates may be prepared from sulfonic acids typically obtained by sulfonation of alkyl-substituted aromatic hydrocarbons. Examples of hydrocarbons include those obtained by alkylating benzene, toluene, xylene, naphthalene, biphenyl, and their halogenated derivatives (eg, chlorobenzene, chlorotoluene, and chloronaphthalene). The alkylating agent typically has about 3 to 70 carbon atoms. The alkaryl sulfonate typically contains about 9 to about 80 or more carbon atoms, more typically about 16 to 60 carbon atoms.

  Non-Patent Document 1 (supra) discloses several overbased metal salts of various sulfonic acids. This is useful as a lubricant and dispersant for lubricating oils. Non-Patent Document 2 similarly discloses several overbased sulfonates that are useful as dispersants / detergents.

Alkaline earth phenates are another useful type of detergent. These detergents include alkaline earth metal hydroxides or oxides (eg, CaO, Ca (OH) ₂ , BaO, Ba (OH) ₂ , MgO, Mg (OH) ₂ ), alkylphenols or sulfurized alkylphenols. It can be made by reacting. Useful alkyl groups include straight or branched _C 1 _{-C 30,} preferably include _C 4 _{-C 20} alkyl group. Examples of suitable phenols include isobutylphenol, 2-ethylhexylphenol, nonylphenol, dodecylphenol and the like. It should be noted that the starting alkylphenol may contain more than one alkyl substituent, each independently being linear or branched. When non-sulfurized alkylphenol is used, the sulfurized product may be obtained by methods well known in the art. These methods include heating a mixture of alkylphenol and sulfurizing agent (including elemental sulfur, sulfur halides such as sulfur dichloride) and then reacting the sulfurized phenol with an alkaline earth metal base.

式中、Ｒは、水素原子、または炭素原子１〜約３０個を有するアルキル基であり、ｎは１〜４の整数であり、Ｍはアルカリ土類金属である。好ましいＲ基は、少なくともＣ_１１、好ましくはＣ_１３以上のアルキル鎖である。Ｒは、任意に、清浄剤の機能を妨げない置換基で置換されてもよい。Ｍは、好ましくは、カルシウム、マグネシウム、またはバリウムである。より好ましくは、Ｍはカルシウムである。 Metal salts of carboxylic acids are also useful as detergents. These carboxylic acid detergents may be prepared by reacting a basic metal compound with at least one carboxylic acid to remove free water from the reaction product. These compounds may be overbased to provide the desired TBN level. A detergent made from salicylic acid is one preferred type of detergent derived from carboxylic acids. Useful salicylates include long chain alkyl salicylates. One useful type of composition is of the formula

In the formula, R is a hydrogen atom or an alkyl group having 1 to about 30 carbon atoms, n is an integer of 1 to 4, and M is an alkaline earth metal. Preferred R groups are at least C ₁₁ , preferably C ₁₃ or higher alkyl chains. R may optionally be substituted with a substituent that does not interfere with the function of the detergent. M is preferably calcium, magnesium or barium. More preferably, M is calcium.

  Hydrocarbyl-substituted salicylic acid may be prepared from phenol by the Kolbe reaction. For further information on the synthesis of these compounds, reference is made to US Pat. The metal salt of hydrocarbyl-substituted salicylic acid may be prepared by metathesis of the metal salt in a polar solvent such as water or alcohol.

  Alkaline earth metal phosphates are also used as detergents.

  The detergent may be a single detergent or known as a hybrid or composite detergent. The latter detergent can provide the properties of two detergents without the need to blend different materials. For example, see US Pat.

  Preferred detergents include calcium phenate, calcium sulfonate, calcium salicylate, magnesium phenate, magnesium sulfonate, magnesium salicylate, and other related ingredients (including boronated detergents). Typically, the total detergent concentration is about 0.01 to about 6.0 wt%, preferably about 0.1 to 0.4 wt%.

Auxiliary dispersant During engine operation, oil-insoluble oxidation by-products are produced. Dispersants help keep these by-products in solution, thus reducing their deposition on metal surfaces. The dispersant may be ashless or essentially form ash. Preferably, the dispersant is ashless. So-called ashless dispersants are organic substances that form virtually no ash during combustion. For example, a dispersant that contains no metal or no metal boride is considered ashless. In contrast, the metal-containing detergents described above form ash during combustion. The auxiliary dispersant may be any non-borated type of dispersant listed above. These auxiliary non-boronated dispersants can be used as received in amounts of about 0.1 to <20 wt%, preferably about 0.1 to 8 wt%.

Pour Point Depressants Conventional pour point depressants (also known as lube oil flow improvers) may be added to the compositions of the present invention if desired. These pour point depressants may be added to the lubricating compositions of the present invention to lower the minimum temperature at which the fluid will flow or can be poured. Examples of suitable pour point depressants include polymethacrylates, polyacrylates, polyarylamides, condensation products of haloparaffin waxes and aromatic compounds, vinyl carboxylate polymers, and terpolymers of dialkyl fumarate, vinyl esters of fatty acids. , And allyl vinyl ether. Patent Literature 41, Patent Literature 42, Patent Literature 43, Patent Literature 44, Patent Literature 45, Patent Literature 46, Patent Literature 47, Patent Literature 48 and Patent Literature 49 provide useful pour point depressants and / or their preparation. Describe. These additives may be used in an amount of about 0.01 to 5 wt%, preferably about 0.01 to 1.5 wt%.

Corrosion Inhibitor / Metal Deactivator Corrosion inhibitors are used to reduce degradation of metal parts in contact with the lubricating oil composition. Suitable corrosion inhibitors include triazoles and thiadiazoles, succinimide derivatives such as higher alkyl-substituted amides of dodecylene succinic acid, tetrapropenyl succinic monoesters, and imidazoline succinic anhydride derivatives. For example, see Patent Literature 50, Patent Literature 51, and Patent Literature 52. These additives may be used in an amount of about 0.01 to 5 wt%, preferably about 0.01 to 1.5 wt%.

Seal Affinity Agent A seal affinity agent helps swell an elastomeric seal by causing a chemical reaction in the fluid or a physical change in the elastomer. Suitable seal affinity agents for lubricating oils include organic phosphates, aromatic esters, aromatic hydrocarbons, and polybutenyl succinic anhydride. These additives may be used in an amount of about 0.01 to 3 wt%, preferably about 0.01 to 2 wt%.

Antifoam agent An antifoam agent may conveniently be added to the lubricating composition. These agents suppress the formation of stable foam. Silicones and organic polymers are typical antifoaming agents. For example, polysiloxanes (such as silicon oil or polydimethylsiloxane) provide antifoam properties. Antifoaming agents are commercially available and may be used in conventional small amounts with other additives such as demulsifiers. Usually the amount of these additives combined is less than 1% and often less than 0.1 percent.

Corrosion Inhibitor / Rust Inhibitor An antirust agent (or corrosion inhibitor) is an additive that protects the metal surface being lubricated against chemical attack by water or other contaminants. A wide variety of these are commercially available. They are cited in Non-Patent Document 1 (supra).

  One type of rust inhibitor is a polar compound that preferentially wets the metal surface and protects it with an oil film. Other types of rust inhibitors absorb water by incorporating it into a water-in-oil emulsion so that only the oil is contacted with the metal surface. Yet another type of rust inhibitor chemically adheres to the metal, resulting in a non-reactive surface. Examples of suitable additives include zinc dithiophosphate, metal phenolate, basic metal sulfonate, fatty acid, and amine. These additives may be used in an amount of about 0.01 to 5 wt%, preferably about 0.01 to 1.5 wt%.

Friction modifier A friction modifier is any substance that can change the coefficient of friction of a surface (which is lubricated by any lubricant or fluid containing these substances). Friction modifiers (also known as friction reducers or lubricants or oily agents) and other these agents (base oils, formulated lubricating oil compositions, or functional fluids are altered and lubricated) (Which modifies the coefficient of friction of the surface) may be effectively used in combination with the base oil or lubricating oil composition of the present invention, if desired. Friction modifiers that reduce the coefficient of friction are particularly advantageous in combination with the base oils and lubricating oil compositions of the present invention. Friction modifiers may include metal-containing compounds or materials, as well as ashless compounds or materials, or mixtures thereof. The metal-containing friction modifier may include a metal salt or a metal ligand complex. At that time, the metal may include an alkali metal, an alkaline earth metal, or a transition group metal. These metal-containing friction modifiers may also have low ash properties. Transition metals may include Mo, Sb, Sn, Fe, Cu, Zn, and the like. Ligand includes alcohol, polyol, glycerol, partial ester glycerin, thiol, carboxylate, carbamate, thiocarbamate, dithiocarbamate, phosphate, thiophosphate, dithiophosphate, amide, imide, amine, thiazole, thiadiazole, dithiazole, diazole , Triazoles, and other polar molecular functional groups (containing effective amounts of O, N, S, or P, individually or in combination) may include hydrocarbyl derivatives. In particular, Mo-containing compounds can be particularly effective. For example, Mo-dithiocarbamate; Mo (DTC), Mo-dithiophosphate; Mo (DTP), Mo-amine; Mo (Am), Mo-alcolate; Mo-alcohol-amide, and the like. Patent Literature 53, Patent Literature 54, Patent Literature 55, Patent Literature 56, Patent Literature 57, Patent Literature 58, Patent Literature 59, Patent Literature 60, Patent Literature 61, Patent Literature 62, Patent Literature 63, Patent Literature 64, Patent Literature 65, Patent Document 66, and Patent Document 67.

  Ashless friction modifiers may also include lubricating substances containing an effective amount of polar groups. For example, hydroxyl-containing hydrocarbyl base oils, glycerides, partial glycerides, glyceride derivatives and the like. The polar groups in the friction modifier may include hydrocarbyl groups that contain effective amounts of O, N, S, or P, individually or in combination. Other friction modifiers that may be particularly effective include, for example, fatty acid salts (both ash-containing and ashless derivatives), fatty alcohols, fatty acid amides, fatty acid esters, hydroxyl-containing carboxylates, and the like Synthetic long chain hydrocarbyl acids, alcohols, amides, esters, hydroxycarboxylates and the like. In some cases, fatty organic acids, fatty amines, and sulfurized fatty acids may be used as suitable friction modifiers.

  Useful concentrations of friction modifiers may range from about 0.01 wt% to 10-15 wt% or more, and often the preferred range is from about 0.1 wt% to 5 wt%. The concentration of molybdenum-containing material is often described in terms of Mo metal concentration. Convenient concentrations of Mo may range from about 10 ppm to 3000 ppm or more, often a preferred range is about 20-2000 ppm, and in some cases a more preferred range is about 30-1000 ppm. All types of friction modifiers may be used alone or in a mixture with the substance of the present invention. Often, a mixture of two or more friction modifiers or a mixture of a friction modifier and another surface active material is also desirable.

During operation of the dispersant mechanism, an oil-insoluble oxidation byproduct is produced. Dispersants help keep these by-products in solution, thus reducing their deposition on the metal surface. The dispersant may be ashless or essentially form ash. Preferably, the dispersant is ashless. So-called ashless dispersants are organic substances that form substantially no ash during combustion. For example, a dispersant containing no metal or no metal boride is considered ashless. In contrast, the metal-containing detergents described above form ash upon combustion.

  Suitable dispersants typically include polar groups attached to relatively high molecular weight hydrocarbon chains. The polar group typically includes at least one of nitrogen, oxygen, or phosphorus. A typical hydrocarbon chain contains 50 to 400 carbon atoms.

  Chemically, many dispersants may be characterized as phenates, sulfonates, sulfurized phenates, salicylates, naphthenates, stearates, carbamates, thiocarbamates, phosphorus derivatives. A particularly useful class of dispersants are alkenyl succinic acid derivatives, typically made by reacting a long chain substituted alkenyl succinic acid compound, usually an anhydrous substituted succinic acid, with a polyhydroxy or polyamino compound. The long chain group (providing solubility in oil) that constitutes the lipophilic part of the molecule is usually a polyisobutylene group. Many examples of this type of dispersant are well known both commercially and in the literature. Exemplary US patents describing these dispersants are: Patent Document 68, Patent Document 69, Patent Document 70, Patent Document 71, Patent Document 72, Patent Document 73, Patent Document 74, Patent Document 75, Patent Document 76, Patent Document 77, Patent Document 78, and Patent Document 79. Other types of dispersants are Patent Literature 80, Patent Literature 81, Patent Literature 82, Patent Literature 83, Patent Literature 84, Patent Literature 85, Patent Literature 86, Patent Literature 87, Patent Literature 88, Patent Literature 89, Patent Literature. 90, Patent Literature 91, Patent Literature 92, Patent Literature 93, Patent Literature 94, Patent Literature 95, Patent Literature 96, Patent Literature 97, Patent Literature 98, Patent Literature 99, and Patent Literature 100. A further description of the dispersant may be found, for example, in US Pat.

  Hydrocarbyl-substituted succinic compounds are common dispersants. In particular, the succinimide, succinic acid ester, or succinic acid ester amide reacts a hydrocarbon-substituted succinic compound (preferably having at least 50 carbon atoms in the hydrocarbon substituent) with at least one equivalent of an alkylene amine. This is particularly useful.

  Succinimide is formed by a condensation reaction of an alkenyl succinic anhydride and an amine. The molar ratio can vary according to the polyamine. For example, the molar ratio of alkenyl succinic anhydride / TEPA can vary from about 1: 1 to about 5: 1. Representative examples are shown in Patent Literature 102, Patent Literature 103, Patent Literature 70, Patent Literature 104, Patent Literature 105, Patent Literature 106, Patent Literature 107, and Patent Literature 108.

  Succinic acid esters are formed by the condensation reaction of alkenyl succinic anhydrides with alcohols or polyols. The molar ratio can vary according to the alcohol or polyol used. For example, the condensation product of alkenyl succinic anhydride and pentaerythritol is a useful dispersant.

  Succinic ester amides are formed by the condensation reaction of alkenyl succinic anhydride and alkanolamine. For example, suitable alkanolamines include ethoxylated polyalkylpolyamines, propoxylated polyalkylpolyamines, and polyalkenyl polyamines such as polyethylene polyamines. One example is propoxylated hexamethylene diamine. A typical example is shown in Patent Document 109.

  The molecular weight of the alkenyl succinic anhydride used in the previous paragraph will typically be in the range of 800-2,500. The above products can be post-reacted with various reagents, such as carboxylic acids such as sulfur, oxygen, formaldehyde, oleic acid, boron compounds such as borate esters or highly borated compounds. The dispersant can be borated at (from about 0.1 to about 5 moles of boron) / (dispersant reaction product moles).

  Mannich group dispersants are made from the reaction of alkylphenols, formaldehyde, and amines. See U.S. Patent No. 6,057,034, incorporated herein by reference. Process acids and catalysts (such as oleic acid and sulfonic acid) can also be part of the reaction mixture. The molecular weight of the alkylphenol is in the range of 800 to 2,500. Representative examples are shown in Patent Literature 88, Patent Literature 111, Patent Literature 112, Patent Literature 113, Patent Literature 114, Patent Literature 115, and Patent Literature 116.

Exemplary high molecular weight aliphatic acid modified Mannich condensation products useful in the present invention can be prepared from high molecular weight alkyl-substituted hydroxyaromatic, or HN (R) ₂ group-containing reactants.

Examples of high molecular weight alkyl-substituted hydroxyaromatics are polypropylphenol, polybutylphenol, and other polyalkylphenols. These polyalkylphenols can be obtained by alkylation of phenol with high molecular weight polypropylene, polybutylene, and other polyalkylene compounds in the presence of an alkylation catalyst (such as BF ₃ ), where the alkyl substituent is It is given to the benzene ring of phenol. This has an average molecular weight of 600 to 100,000.

Examples of HN (R) ₂ group-containing reactants are alkylene polyamines, mainly polyethylene polyamines. Other representative organic compounds containing at least one HN (R) ₂ group suitable for use in the preparation of Mannich condensation products are well known and include mono- and di-amino alkanes, and Substituted analogues of For example, ethylamine and diethanolamine; aromatic diamines such as phenylenediamine, diaminonaphthalene; heterocyclic amines such as morpholine, pyrrole, pyrrolidine, imidazole, imidazolidine, and piperidine; melamine and substituted analogs thereof.

Examples of alkylene polyamide reactants include ethylenediamine, diethylenetriamine, triethylenetetraamine, tetraethylenepentamine, pentaethylenehexamine, hexaethyleneheptamine, heptaethyleneoctamine, octaethylenenonamine, nonaethylenedecamine, and decaethylene Undecamine as well as mixtures of these amines are included. This has a nitrogen content corresponding to alkylene polyamines of the formula _{H 2 N- (Z-NH-)} n H ( described above). Z is a bivalent ethylene and n is 1-10 in the above formula. Corresponding propylene polyamines (such as propylene diamine and di-, tri-, tetra-, pentapropylene tri-, tetra-, penta-, and hexaamine) are also suitable reactants. Alkylene polyamines are usually obtained by reaction of ammonia with dihaloalkanes (such as dichloroalkanes). Thus, alkylene polyamines (obtained by reaction of 2 to 11 moles of ammonia and 1 to 10 moles of dichloroalkane having 2 to 6 carbon atoms and having chlorine on a different carbon) are suitable alkylene polyamine reactions. Is the body.

  Aldehyde reactants useful for preparing polymeric products useful in the present invention include aliphatic aldehydes. Formaldehyde (also as paraformaldehyde and formalin), acetaldehyde, and aldol (β-hydroxybutyraldehyde). Formaldehyde or formaldehyde-forming reactants are preferred.

  Hydrocarbyl-substituted amine ashless dispersants are well known to those skilled in the art. For example, see Patent Literature 83, Patent Literature 84, Patent Literature 86, Patent Literature 117, Patent Literature 118, and Patent Literature 38. This is a book which is incorporated herein by reference in its entirety.

  Boronated dispersants can be used. Any dispersant containing either nitrogen and / or oxygen atoms or both can be borated.

  Preferred dispersants include boronated and nonborated succinimides. This includes derivatives from mono-succinimide, bis-succinimide, and / or mixtures of mono- and bis-succinimide. The hydrocarbyl succinimide is then derived from a hydrocarbylene group such as polyisobutylene having a Mn of about 500 to about 5000, or a mixture of these hydrocarbylene groups. Other preferred dispersants include succinic acid-esters and amides, alkylphenol-polyamine-linked Mannich adducts, their capped derivatives, and other related compounds. These additives may be used in an amount of about 0.1-20 wt%, preferably about 0.1-8 wt%.

Typical Additive Amount If the lubricating oil composition contains one or more of the additives described above, the additive is blended into the composition in an amount sufficient to perform its intended function. The Typical amounts of these additives useful in the present invention are shown in Table 1 below.

  Note that many additives are shipped from the manufacturer and used in the formulation with a certain amount of base oil solvent. Accordingly, the weights in the following table, as well as other amounts described in this patent, relate to the amount of active ingredient (which is the non-solvent portion of the ingredient) unless otherwise stated. The wt% shown below is based on the total weight of the lubricating oil composition.

  The invention is illustrated by the following non-limiting examples and comparative examples.

  The following examples and comparative examples are gear oils that meet the nominal 30 grade viscosity target unless otherwise indicated.

  The traction coefficient is determined using a minitraction device. This is a computer controlled precision traction measurement system. A small sample of fluid is placed in the test cell and the device automatically operates through a range of speed, slide / roll ratio (slip rate), temperature, and load to produce a comprehensive traction map of the test fluid. , Without any driver involvement. The MTM can be used in the form of different specimens. However, the standard specimens used herein are polished 19.05 mm (3/4 inch) balls and 50.0 mm diameter discs. It is manufactured from AISI 52100 bearing steel. The specimen is designed to be a single use disposable. The specimens are independently driven by a DC servo motor to drive high precision speed control, particularly at a low slide / roll ratio. Each specimen is end mounted to the shaft in a small stainless steel test fluid bath. The vertical axis and the drive system (supporting a 50 mm diameter specimen) are fixed. However, the shaft and drive system (supporting a 19.05 mm diameter specimen) is supported by the gimbal arrangement, so that it can rotate around two orthogonal axes. One axis is perpendicular to the direction of action of the load and the other is relative to the direction of traction force. The traction force loading and restraint action is done by a high stiffness force transducer generally mounted in a gimbal arrangement to minimize the overall support runout. The output from these force transducers is monitored directly by a personal computer (PC). The test conditions used herein are a load of 16 Newton, a temperature of 100 ° C., and a slide / roll ratio of 30% (16 N / 100 ° C./30 SSR).

Comparative Examples 1, 2, and 3 used adipate ester of KV (100 ° C.) 5.1-5.5 mm ² / sec, while Comparative Example 4 was KV (100 ° C.) 5.1-5.5 mm ² The difference is that different additive packages are used while still using the adipate ester / sec.

Examples 1 and 2 of the inventive formulation differed in the nature of the esters used, using the same PAO combinations and additive packages as Comparative Examples 1, 2, 3, 6, and 7. Example 1 uses a polyol ester having a KV (100 ° C.) of 4.2 to 4.5 mm ² / sec and a pour point of less than −45 ° C., and Example 2 uses KV (100 ° C.) of 2.7 mm ² / sec, An adipate (diester) having a pour point of less than -45 ° C was used.

  In either case, inventive oil Examples 1 and 2 show unexpected improvements in all low temperature viscosity properties and traction coefficients. The Brookfield viscosities (−40 ° C.) of Examples 1 and 2 are 25,747 cP and 20,547 cP, respectively, the CCS viscosities (−25 ° C.) are 4118 cP and 3,357 cP, respectively, and the traction coefficients are respectively 0.01969 and 0.01945. The flash points were 242 and 234 ° C., respectively, while the NOACK volatility was 9.0 and 12.7%, respectively. These improvements in low temperature viscosity and traction coefficient are to be expected from these small changes in the viscosity of the esters used in combination with mixed PAO substrates, while leaving acceptable NOACK volatility and flash point. I could not.

Comparative Example 5 is similar to Comparative Example 4 but with Emoline 2958 (di-2-hexyl adipate with a reported value of KV (100 ° C.) 2.8-2.9 mm ² / sec, pour point less than −45 ° C. Conceivable) was used in place of 5.1-5.5 mm ² / sec adipate. Comparative Examples 6 and 7 are similar to Comparative Examples 1, 2, and 3, except that Esterex ™ M31 (ethylhexyl polymitate monoester, KV (100 ° C.) 2.7 mm ² / sec, pour point 3 ° C. ) And Esterer ™ M11 (nonylheptanoate monoester, literature value KV (100 ° C.) 1.25 to 1.45 mm ² / sec, pour point—below 45 ° C.) 5.1 to 5.5 mm ² Per second of adipate (diester) / sec.

The formulations of Comparative Examples 6 and 7 showed CCS viscosity and traction coefficient that met the specific goals of the present invention, and in the case of Comparative Example 7, also showed Brookfield viscosity, but they were in the actual working environment. If used, it will be shown to be undesirable and insufficient from a practical point of view. The formulation of Comparative Example 6 showed quite insufficient high Brookfield viscosity, while the formulation of Comparative Example 7 showed insufficient flash point and NOACK volatility. Comparative Example 5 shows that even when the desired KV diester is used, if the PAO substrate combination does not correspond to that cited in this application, the resulting formulated oil will have a target of 9 to 12.5 mm ² / It has an KV out of seconds and exhibits unacceptable Brookfield viscosity, unacceptable CCS viscosity, and does not achieve the desired traction coefficient.

Claims (34)

A method for improving fuel economy and energy efficiency of a heavy duty gear mechanism operating under high load conditions,
A step of operating the mechanism under a high load condition while lubricating a heavy load gear mechanism using a lubricating oil composition, the lubricating oil composition comprising:
20-75 wt% polyalphaolefin fluid having a kinematic viscosity (100 ° C.) of 2-10 mm ² / sec;
5-40 wt% polyalphaolefin fluid having a kinematic viscosity (100 ° C.) of 150-3,000 mm ² / sec;
A polyalphaolefin fluid having a kinematic viscosity (100 ° C.) of 20-100 mm ² / sec, 10-40 wt%; and one or more polyols having a kinematic viscosity (100 ° C.) of 2-5 mm ² / sec and a pour point of at least −25 ° C. Esters or diesters 5 to 20 wt%
And further comprising at least one gear oil performance additive,
The lubricating oil composition has a kinematic viscosity (100 ° C.) of 9 to 12.5 mm ² / sec and has a traction coefficient value of 0.0197 or less measured as a 16 N / 100 ° C./30 SSR value, a Brookfield viscosity (− 40 ° C) 26,000 cP or less and CCS viscosity (−25 ° C.) 4200 cP or less, a flash point of 220 ° C. or more, and NOACK volatility of 15% or less. And ways to improve energy efficiency. The lubricating oil composition is
PAO fluid with kinematic viscosity (100 ° C.) 3.5-8 mm ² / sec 30-60 wt%;
PAO fluid having a kinematic viscosity of 150-1500 mm ² / sec 5-20 wt%;
PAO fluid with kinematic viscosity (100 ° C.) 20-80 mm ² / sec 15-30 wt%; and ester with kinematic viscosity (100 ° C.) 2-4.5 mm ² / sec 5-15 wt%
The method of claim 1 further comprising at least one gear oil performance additive. The method of claim 1, wherein the lubricating oil composition comprises 30-60 wt% PAO fluid having a kinematic viscosity (100 ° C.) of 2-10 mm ² / sec. The method of claim 1, wherein the lubricating oil composition comprises 5-20 wt% PAO fluid having a kinematic viscosity (100 ° C.) of 150-3000 mm ² / sec. The method of claim 1, wherein the lubricating oil composition comprises 15-30 wt% PAO fluid having a kinematic viscosity (100 ° C.) of 20-100 mm ² / sec. The method according to claim 1, wherein the ester constitutes 5 to 15 wt% of the lubricating oil and has a kinematic viscosity (100 ° C.) of ^{2 to} 4.5 mm ² / sec. The lubricating oil composition is
PAO fluid having a kinematic viscosity (100 ° C.) of 3.5-6 mm ² / sec, 45-55 wt%;
PAO fluid having a kinematic viscosity (100 ° C.) of 150-500 mm ² / sec 8-12 wt%; and PAO fluid having a kinematic viscosity 20-60 mm ² / sec 18-22 wt%
The method according to claim 1, 2, 3, 4, 5 or 6.   The method of claim 7, wherein the ester is a non-polyol ester. 9. The method of claim 8, wherein the non-polyol ester comprises 5-15 wt% of the lubricating oil and has a kinematic viscosity (100 [deg.] C.) of 2.5-4.5 mm < ² > / sec.   The said lubricating oil composition is characterized by exhibiting a traction coefficient value of 0.0191 or less measured as 16 N / 100 ° C / 30 SSR value. The method described in 1.   The lubricating oil composition is characterized by exhibiting a Brookfield viscosity (−40 ° C.) of 21,000 cP or less, a flash point of 230 ° C. or more, and a NOACK volatility of 15% or less. The method according to 3, 4, 5 or 6.   The method according to claim 1, 2, 3, 4, 5 or 6, wherein the lubricating oil composition is characterized by exhibiting a CCS viscosity (-25 ° C) of 3,600 cP or less.   The method of claim 1, 2, 3, 4, 5 or 6, wherein the lubricating oil composition is characterized by exhibiting a CCS viscosity (-25 ° C) of 3400 cP or less.   The lubricating oil composition has a traction coefficient value of 0.0191 or less, a Brookfield viscosity (−40 ° C.) of 21,000 cP or less, and a CCS viscosity (−25 ° C.) of 3600 cP or less, measured as 16 N / 100 ° C./30 SSR value. 8. The method of claim 7, characterized by exhibiting a point of 230 [deg.] C. or lower and NOACK volatility of 13% or lower. The method according to claim 14, wherein the ester comprises 5 to 15 wt% of the lubricating oil and has a kinematic viscosity (100 ° C.) of 2.5 to 4.5 mm ² / sec. The method according to claim 9, wherein the ester constitutes 8 to 12 wt% of the lubricating oil and has a kinematic viscosity (100 ° C.) of 2.5 to 4.5 mm ² / sec.   The method of claim 1, 2, 3, 4, 5, or 6, wherein the lubricating oil composition is characterized by not containing a viscosity index improver. 20-75 wt% polyalphaolefin fluid having a kinematic viscosity (100 ° C.) of 2-10 mm ² / sec;
5-40 wt% polyalphaolefin fluid having a kinematic viscosity (100 ° C.) of 150-3,000 mm ² / sec;
A polyalphaolefin fluid having a kinematic viscosity (100 ° C.) of 20-100 mm ² / sec, 10-40 wt%; and one or more polyols having a kinematic viscosity (100 ° C.) of 2-5 mm ² / sec and a pour point of at least −25 ° C. Esters or diesters 5 to 20 wt%
A lubricating oil composition further comprising at least one gear oil performance additive comprising:
A traction coefficient value of 0.0197 or less, a Brookfield viscosity (−40 ° C.) of 26,000 cP or less, having a kinematic viscosity (100 ° C.) of 9 to 12.5 mm ² / sec and measured as a value of 16 N / 100 ° C./30 SSR And a CCS viscosity (−25 ° C.) of 4200 cP or less, a flash point of 220 ° C. or more, and a NOACK volatility of 15% or less. PAO fluid with kinematic viscosity (100 ° C.) 3.5-8 mm ² / sec 30-60 wt%;
PAO fluid having a kinematic viscosity of 150-1500 mm ² / sec 5-20 wt%;
PAO fluid with kinematic viscosity (100 ° C.) 20-80 mm ² / sec 15-30 wt%; and ester with kinematic viscosity (100 ° C.) 2-4.5 mm ² / sec 5-15 wt%
The lubricating oil composition of claim 18, further comprising at least one gear oil performance additive. The lubricating oil composition according to claim 18, comprising 30-60 wt% of a PAO fluid having a kinematic viscosity (100 ° C.) of 2-10 mm ² / sec. The lubricating oil composition according to claim 18, comprising 5 to 20 wt% of a PAO fluid having a kinematic viscosity (100 ° C.) of 150 to 3000 mm ² / sec. The lubricating oil composition according to claim 18, comprising 15-30 wt% PAO fluid having a kinematic viscosity (100 ° C.) of 20-100 mm ² / sec. The lubricating oil composition according to claim 18, wherein the ester constitutes 5 to 15 wt% of the lubricating oil and has a kinematic viscosity (100 ° C.) of ^{2 to} 4.5 mm ² / sec. PAO fluid having a kinematic viscosity (100 ° C.) of 3.5-6 mm ² / sec, 45-55 wt%;
20. A PAO fluid having a kinematic viscosity (100 ° C.) of 150-500 mm ² / sec, 8-12 wt%; and a PAO fluid having a kinematic viscosity of 20-60 mm ² / sec, 18-22 wt%. , 20, 21, 22 or 23.   The lubricating oil composition of claim 24, wherein the ester is a non-polyol ester. The non-polyol esters constitute a 5 to 15 wt% of the lubricating oil composition, kinematic viscosity (100 ℃) 2.5~4.5mm lubricating oil according to claim 25, characterized in that it has a ² / sec Composition.   24. Lubricating oil composition according to claim 18, 19, 20, 21, 22 or 23, characterized by a traction coefficient value of 0.0191 or less measured as 16 N / 100 [deg.] C./30 SSR value.   24. The Brookfield viscosity (−40 ° C.) of 21,000 cP or less, a flash point of 230 ° C. or more and NOACK volatility of 15% or less, according to claim 18, 19, 20, 21, 22, or 23 Lubricating oil composition.   24. Lubricating oil composition according to claim 18, 19, 20, 21, 22 or 23, characterized by a CCS viscosity (-25 [deg.] C) of 3,600 cP or less.   24. Lubricating oil composition according to claim 18, 19, 20, 21, 22 or 23, characterized by a CCS viscosity (-25 [deg.] C) of 3400 cP or less.   Traction coefficient value measured as 16 N / 100 ° C./30 SSR value 0.0191 or less, Brookfield viscosity (−40 ° C.) 21,000 cP or less, CCS viscosity (−25 ° C.) 3600 cP or less, flash point 230 ° C. or less, and NOACK volatilization 25. Lubricating oil composition according to claim 24, characterized by a property of 13% or less. The ester constitutes a 5 to 15 wt% of the lubricating oil, the lubricating oil composition according to claim 31, characterized in that it has a kinematic viscosity (100 ℃) 2.5~4.5mm ² / sec. 27. The lubricating oil composition of claim 26, wherein the ester comprises 8-12 wt% of the lubricating oil and has a kinematic viscosity (100 [deg.] C.) of 2.5-4.5 mm < ² > / sec.   24. Lubricating oil composition according to claim 18, 19, 20, 21, 22 or 23, characterized by not containing a viscosity index improver.