JP6748519B2 - Viscosity index improver composition and lubricating oil composition - Google Patents

Description

The present invention relates to a viscosity index improver composition and a lubricating oil composition.

Lubricating oils such as ATF, CVTF, and MTF used in automobile transmissions decrease in viscosity as the temperature rises, but in practice, the viscosity should not change as much as possible over a wide range from low temperature to high temperature, that is, the viscosity index should be high. Is desirable. In recent years, as a means for improving fuel economy, it has been performed to reduce the viscosity resistance of lubricating oil to reduce viscous resistance. However, reducing the viscosity of the lubricating oil may cause various problems such as oil leakage and seizure.
Therefore, as a means for improving fuel economy, there is a method of using a viscosity index improver. When the viscosity index is high, the viscosity resistance of the lubricating oil at low temperatures is low, which leads to an improvement in fuel efficiency. Therefore, a method of adding a viscosity index improver to the lubricating oil to improve the temperature dependence of the viscosity is widely used. As such viscosity index improvers, methacrylic acid ester copolymers (Patent Documents 1 to 4), olefin copolymers (Patent Document 5), macromonomer copolymers (Patent Document 6) and the like are known. There is.
However, the above-mentioned lubricating oil composition has a problem that the effect of improving the viscosity index is not yet sufficient, and the shear stability after long-time operation and the low temperature characteristics at the time of starting are not sufficient in practical use.

Japanese Patent No. 2732187 Japanese Patent No. 2941392 JP, 7-62372, A JP, 2004-307551, A JP, 2005-2004454, A JP, 2008-546894, A

An object of the present invention is to provide a viscosity index improver having an excellent effect of improving the viscosity index, and a viscosity index improver composition and a lubricating oil composition which show little decrease in viscosity due to long-term use and have excellent low temperature viscosity.

As a result of intensive studies, the present inventors have reached the present invention. That is, the present invention essentially comprises a monomer (a) represented by the following general formula (1) and a (meth)acrylic acid linear alkyl ester (b) having a linear alkyl group having 1 to 4 carbon atoms. A copolymer (A) to be used as a monomer and an ester having a kinematic viscosity at 100° C. of 1.0 to 2.5 mm ² /s and a kinematic viscosity at 40° C. of 2.5 to 7.0 mm ² /s. A lubricating oil composition comprising a viscosity index improver composition comprising an oil base oil, wherein (A) is based on the number of moles of the constituent monomer of (A) as a constituent monomer ( b) it was contained 80-95 mol%, and (a) the molar ratio of (b) (a / b) is Ri copolymer der which is 0.010 to 0.200, 100 of the lubricating oil composition The lubricating oil composition has a kinematic viscosity at 4.2° C. of 4.2 to 5.7 mm ² /s and a viscosity index of 398 to 800 .

[In General Formula (1), R ¹ is a hydrogen atom or a methyl group; —X ¹ — is a group represented by —O— or —NH—, and R ² is a straight chain having 2 to 4 carbon atoms or It is a branched alkylene group, p is an integer of 0 to 20, R ² when p is 2 or more may be the same or different, and the (R ² O) _p portion may be a random bond or a block bond; R ³ is a branched alkyl group having 32 to 44 carbon atoms. ]

The viscosity index improver composition of the present invention has the effects of having a high viscosity index, a small decrease in viscosity due to long-term shearing, and a difficulty in increasing viscosity at low temperatures.

The viscosity index improver composition of the present invention comprises a monomer (a) represented by the general formula (1) and a (meth)acrylic acid linear alkyl ester (b) having a linear alkyl group having 1 to 4 carbon atoms. And a copolymer (A) containing as an essential constituent monomer. In addition, (meth)acrylic acid means acrylic acid or methacrylic acid.

The copolymer (A) in the present invention has (a) represented by the general formula (1) as an essential constituent monomer. R ¹ in the general formula (1) is a hydrogen atom or a methyl group. Of these, the methyl group is preferable from the viewpoint of the effect of improving the viscosity index.

-X ¹ in the general formula (1) - is a group represented by -O- or -NH-. Of these, -O- is preferable from the viewpoint of the effect of improving the viscosity index.

R ² in the general formula (1) is a linear or branched alkylene group having 2 to 4 carbon atoms, and examples thereof include an ethylene group, a propylene group, and a butylene group. Examples of the propylene group include a 1,2- or 1,3-propylene group. Examples of the butylene group include a 1,2-, 1,3- or 1,4-butylene group. Of these, the ethylene group and the propylene group, which are linear or branched alkylene groups having 2 to 3 carbon atoms, are preferable from the viewpoint of the effect of improving the viscosity index.

R ³ in the general formula (1) is a branched alkyl group having 32 to 44 carbon atoms. Examples of the branched alkyl group having 32 to 44 carbon atoms include 2-tetradecyl octadecyl group (32 carbon atoms), 2-tetradecylicosyl group (34 carbon atoms), 2-hexadecyl octadecyl group (34 carbon atoms), 2 -Hexadecylicosyl group (36 carbon atoms), 2-isohexadecylisoicosyl group (36 carbon atoms), 2-octadecyldocosyl group (40 carbon atoms), 2-icosyltetracosyl group (carbon number) 44), olefin [eg, propylene oligomer (11 to 15 mer), ethylene/propylene oligomer (11 to 21 mer, molar ratio 20/1 to 1/10) and isobutene oligomer (8 to 11 mer)] The residue etc. which removed the hydroxyl group from the obtained oxo alcohol are mentioned.
Among the branched alkyl groups having 32 to 44 carbon atoms, the branched alkyl groups having 32 to 40 carbon atoms are preferable from the viewpoint of the solubility of the viscosity index improver in the ester oil base oil, and the more preferable one is the carbon number. A branched alkyl group having 32 to 36, particularly preferably a branched alkyl group having 32 to 36 carbon atoms, which is branched at the 2-position of the alkyl group.

P in the general formula (1) is an integer of 0 to 20, and preferably an integer of 0 to 5 from the viewpoint of the viscosity index improving effect and low temperature viscosity. More preferably, it is an integer of 0-2. When p is 2 or more, R ² may be the same or different, and when the (R ² O) _p moieties are different, they may be a random bond or a block bond. From the viewpoint of low temperature viscosity, a random bond is preferable.

Specific examples of the monomer (a) include 2-tetradecyl octadecyl (meth)acrylate, 2-tetradecylicosyl (meth)acrylate, ethylene glycol mono-2-tetradecylicosyl group and (meth). Ester with acrylic acid, 2-hexadecyloctadecyl (meth)acrylate, 2-hexadecylicosyl (meth)acrylate, 2-isohexadecylisoicosyl (meth)acrylate, 2-(meth)acrylic acid 2- Examples thereof include octadecyl docosyl, 2-methosacrylic acid 2-icosyl tetracosyl, and (meth)acrylic acid (propylene oligomer).
Among the monomers (a), from the viewpoints of the viscosity index and the low temperature viscosity, preferable are 2-tetradecyl octadecyl (meth)acrylate, 2-tetradecylicosyl (meth)acrylate, and (meth)acrylic acid 2 -Hexadecyl octadecyl, particularly preferred is 2-tetradecyl octadecyl (meth)acrylate, 2-tetradecyl icosyl (meth)acrylate, and most preferred is 2-tetradecyl octadecyl (meth)acrylate.

The copolymer (A) in the present invention further comprises (meth)acrylic acid linear alkyl ester (b) having a linear alkyl group having 1 to 4 carbon atoms as an essential constituent monomer.

As the (meth)acrylic acid linear alkyl ester (b) having a linear alkyl group having 1 to 4 carbon atoms, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, Examples include n-butyl (meth)acrylate.
Preferred among (b) are (meth)acrylic acid linear alkyl esters having a linear alkyl group having 1 to 3 carbon atoms, and more preferred are methyl (meth)acrylate and ethyl (meth)acrylate. Particularly preferred is methyl (meth)acrylate.

(A) has a monomer (c) represented by the general formula (2) and a linear alkyl group having 12 to 36 carbon atoms in addition to (a) and (b) as constituent monomers (meta). ) It is preferable to contain at least one member selected from the group consisting of alkyl acrylate (d) from the viewpoint of low temperature viscosity of the lubricating oil composition.

[In General Formula (2), R ⁴ is a hydrogen atom or a methyl group; —X ² — is a group represented by —O— or —NH—, and R ⁵ is a straight chain having 2 to 4 carbon atoms or It is a branched alkylene group, q is an integer of 0 to 20, R ^{5 s} when q is 2 or more may be the same or different, and the (R ⁵ O) _q moiety may be a random bond or a block bond; R ⁶ is each independently a linear or branched alkyl group having 6 to 14 carbon atoms]

R ⁴ in the general formula (2) is a hydrogen atom or a methyl group. Of these, a methyl group is preferable from the viewpoint of viscosity index.

-X ² in the general formula (2) - is a group represented by -O- or -NH-. Of these, a group represented by —O— is preferable from the viewpoint of viscosity index.

R ⁵ in the general formula (2) is an alkylene group having 2 to 4 carbon atoms. The alkylene group having 2 to 4 carbon atoms includes ethylene group, isopropylene group, 1,2- or 1,3-propylene group, isobutylene group, and 1,2-, 1,3- or 1,4-butylene group. Is mentioned.

Q in the general formula (2) is an integer of 0 to 20, and preferably an integer of 0 to 5 from the viewpoint of the viscosity index improving effect and low temperature viscosity. More preferably, it is an integer of 0-2. When p is 2 or more, A may be the same or different, and when different, they may be random bonds or block bonds. From the viewpoint of low temperature viscosity, a random bond is preferable.

^{R 6} in the general formula (3) are each independently a linear or branched alkyl group having 6 to 14 carbon atoms. Specifically, straight-chain alkyl such as n-hexyl group, n-pentyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tetradecyl group In addition, branched alkyl groups such as an isohexyl group, an isooctyl group, an isodecyl group, an isododecyl group, and an isotetradecyl group are included.
Among the linear or branched alkyl groups having 6 to 14 carbon atoms, the linear or branched alkyl groups having 7 to 13 carbon atoms are preferable from the viewpoint of viscosity index and low-temperature viscosity, and more preferable are 8 to 8 carbon atoms. A straight-chain or branched alkyl group having 12 carbon atoms, particularly preferably a straight-chain or branched alkyl group having 8 to 10 carbon atoms.

Specific examples of the monomer (c) include 2-hexyloctyl (meth)acrylate, 2-octyldecyl (meth)acrylate, ethylene glycol mono-2-octylpentadecyl ether and (meth)acrylic acid. Ester, 2-octyldodecyl (meth)acrylate, 2-isooctylisododecyl (meth)acrylate, 2-decyltetradecyl (meth)acrylate, 2-isodecylisotetradecyl (meth)acrylate, (meth ) 2-dodecyl hexadecyl acrylate, 2-dodecyl pentadecyl (meth)acrylate, N-2-octyldecyl (meth)acrylamide, and the like.
Among the monomers (c), 2-octyldodecyl (meth)acrylate, 2-isooctylisododecyl (meth)acrylate, and 2-(meth)acrylic acid 2- are preferable from the viewpoint of viscosity index and low-temperature viscosity. Decyl tetradecyl, 2-isodecyl isomethydecadecyl (meth)acrylate, 2-dodecyl hexadecyl (meth)acrylate, and particularly preferred are 2-octyldodecyl (meth)acrylate and 2-iso(meth)acrylate. Octyl isododecyl, 2-decyl tetradecyl (meth)acrylate, 2-isodecyl isotetradecyl (meth)acrylate, most preferably 2-octyldodecyl (meth)acrylate, 2-decyl (meth)acrylate It is tetradecyl.

Specific examples of the (meth)acrylic acid linear alkyl ester (d) having a linear alkyl group having 12 to 36 carbon atoms include (meth)acrylic acid n-dodecyl, (meth)acrylic acid n-tridecyl, and (meth ) N-tetradecyl acrylate, n-pentadecyl (meth)acrylate, n-hexadecyl (meth)acrylate, n-octadecyl (meth)acrylate, n-icosyl (meth)acrylate, n-(meth)acrylate Examples thereof include docosyl, n-tetracosyl (meth)acrylate, n-triacontyl (meth)acrylate, and n-hexatriacontyl (meth)acrylate.
Among (d), from the viewpoint of viscosity index and low temperature viscosity, (meth)acrylic acid linear alkyl ester having a linear alkyl group having 12 to 20 carbon atoms is preferable, and more preferable is 12 to 18 carbon atoms. Is a (meth)acrylic acid linear alkyl ester having a linear alkyl group, and particularly preferably is a (meth)acrylic acid linear alkyl ester having a linear alkyl group having 14 to 18 carbon atoms.

The solubility parameter of (A) (hereinafter abbreviated as SP value) is preferably 9.0 to 10.0 (cal/cm ³ ) ¹ from the viewpoint of the effect of improving the viscosity index and the solubility in the ester oil base oil. ^{/ 2,} more preferably ^{9.1~9.7 (cal / cm 3) 1/2} , more preferably from 9.2~9.6cal ^/ cm ^{3) 1/2.}
The SP values of (A) and ester oil base oils are values calculated by the method described in the Fedors method (Polymer Engineering and Science, February, 1974, Vol. 14, No. 2 P. 147 to 154). is there.
The SP value of (A) is calculated by calculating the SP value of each of the monomers constituting (A) by the above method, and the SP value of each monomer is calculated based on the mole fraction of the constituent monomer units. The average value.
The SP value of (A) can be set to a predetermined value by appropriately adjusting the SP value and the mole fraction of the monomer used.

Further, the dispersity of the SP value of (A) is preferably 0.10 to 1.00, and more preferably 0. 0 from the viewpoint of the effect of improving the viscosity index and the solubility in the lubricating base oil ester oil base oil. It is 10 to 0.80, more preferably 0.10 to 0.70, particularly preferably 0.15 to 0.60, and most preferably 0.15 to 0.50.
In addition, the dispersion degree of the SP value in (A) can be calculated and determined using the following mathematical expression (1). The dispersity of the SP value of (A) can be set to a predetermined value by appropriately adjusting the mole fraction of the constituent monomers.

(Dispersion degree of SP value of (A)) = Σ [(molar fraction of constituent monomer) x {(SP value of homopolymer of constituent monomer)-(SP value of (A))} ² ] (1)

(A) further comprises a nitrogen atom-containing monomer (excluding (a) and (c)) (e), a hydroxyl group-containing monomer (f), and a phosphorus atom-containing monomer (g). It may be a copolymer having at least one selected from the group as a constituent monomer.
Examples of the nitrogen atom-containing monomer (e) include the following monomers (e1) to (e4) other than (a) and (c).

Amide group-containing vinyl monomer (e1):
(Meth)acrylamide, monoalkylamino(meth)acrylamide [one nitrogen atom having one alkyl group having 1 to 4 carbon atoms bonded thereto; for example, N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide, N- Isopropyl (meth)acrylamide and Nn- or isobutyl (meth)acrylamide, etc.], monoalkylaminoalkyl (meth)acrylamide [aminoalkyl group in which one alkyl group having 1 to 4 carbon atoms is bonded to a nitrogen atom (carbon number 2-6); for example N-methylaminoethyl(meth)acrylamide, N-ethylaminoethyl(meth)acrylamide, N-isopropylamino-n-butyl(meth)acrylamide and Nn- or isobutylamino-. n-butyl (meth)acrylamide, etc.], dialkylamino (meth)acrylamide [having two alkyl groups having 1 to 4 carbon atoms bonded to a nitrogen atom; for example, N,N-dimethyl (meth)acrylamide, N,N- Diethyl (meth)acrylamide, N,N-diisopropyl (meth)acrylamide and N,N-di-n-butyl (meth)acrylamide, etc.], dialkylaminoalkyl (meth)acrylamide [alkyl having 1 to 4 carbon atoms at the nitrogen atom] Those having an aminoalkyl group (having 2 to 6 carbon atoms) in which two groups are bonded; for example, N,N-dimethylaminoethyl (meth)acrylamide, N,N-diethylaminoethyl (meth)acrylamide, N,N-dimethylamino Propyl (meth)acrylamide and N,N-di-n-butylaminobutyl (meth)acrylamide, etc.], N-vinylcarboxylic acid amide [N-vinylformamide, N-vinylacetamide, N-vinyl-n- or isopropylionyl Amido and N-vinylhydroxyacetamide, etc.] and the like having a nitrogen atom only in the amide group.

Nitro group-containing monomer (e2):
4-nitrostyrene etc. are mentioned.

Vinyl monomer containing primary to tertiary amino group (e3):
Primary amino group-containing vinyl monomer {alkenylamine having 3 to 6 carbon atoms [(meth)allylamine and crotylamine, etc.], aminoalkyl (2 to 6 carbon atoms) (meth)acrylate [aminoethyl (meth)acrylate, etc.] }; Secondary amino group-containing vinyl monomer {monoalkylaminoalkyl(meth)acrylate [having an aminoalkyl group (having 2 to 6 carbon atoms) in which one nitrogen atom has an alkyl group having 1 to 6 carbon atoms bonded thereto] For example, t-butylaminoethyl (meth)acrylate and methylaminoethyl (meth)acrylate, etc.], C 6-12 dialkenylamine [di(meth)allylamine, etc.]}; tertiary amino group-containing vinyl monomer {Dialkylaminoalkyl (meth)acrylate [having an aminoalkyl group (having 2 to 6 carbon atoms) in which two alkyl groups having 1 to 6 carbon atoms are bonded to a nitrogen atom; for example, dimethylaminoethyl (meth)acrylate and diethylaminoethyl (Meth)acrylate, etc., alicyclic (meth)acrylate having a nitrogen atom [morpholinoethyl (meth)acrylate, etc.], aromatic vinyl monomer [N,N-diphenylaminoethyl (meth)acrylamide, N, N-dimethylaminostyrene, 4-vinylpyridine, 2-vinylpyridine, N-vinylpyrrole, N-vinylpyrrolidone and N-vinylthiopyrrolidone]}, and their hydrochlorides, sulfates, phosphates or lower alkyls. Examples thereof include salts of monocarboxylic acids (having 1 to 8 carbon atoms) (acetic acid, propionic acid, etc.).

Vinyl monomer containing nitrile group (e4):
(Meth)acrylonitrile and the like can be mentioned.

Among (d), (e1) and (e3) are preferable, and more preferable are N,N-diphenylaminoethyl(meth)acrylamide, dimethylaminoethyl(meth)acrylamide, diethylaminoethyl(meth)acrylamide. , Dimethylaminopropyl(meth)acrylamide, dimethylaminoethyl(meth)acrylate and diethylaminoethyl(meth)acrylate, and particularly preferred are dimethylaminoethyl(meth)acrylate and diethylaminoethyl(meth)acrylate.

Hydroxyl group-containing monomer (f):
Hydroxyl group-containing aromatic vinyl monomer (p-hydroxystyrene etc.), hydroxyalkyl (C2-6) (meth)acrylate [2-hydroxyethyl (meth)acrylate, and 2- or 3-hydroxypropyl (meth) Acrylate and the like], mono- or di-hydroxyalkyl (C 1 to C 4) substituted (meth)acrylamide [N,N-dihydroxymethyl (meth)acrylamide, N,N-dihydroxypropyl (meth)acrylamide, N,N- Di-2-hydroxybutyl (meth)acrylamide, etc.], vinyl alcohol, alkenol having 3 to 12 carbon atoms [(meth)allyl alcohol, crotyl alcohol, isocrotyl alcohol, 1-octenol, 1-undecenol, etc.], carbon Alkene monool or alkene diol [1-buten-3-ol, 2-buten-1-ol and 2-butene-1,4-diol, etc.] having a number of 4 to 12, hydroxyalkyl (having 1 to 6 carbon atoms) alkenyl Alkenyl (carbon number of 3 to 10) ether (2-hydroxyethylpropenyl ether, etc.), polyhydric (3 to 8 valent) alcohol (glycerin, pentaerythritol, sorbitol, sorbitan, diglycerin, sugar, sucrose, etc.) 3-10) ether or (meth)acrylate [sucrose (meth)allyl ether, etc.] and the like;
Polyoxyalkylene glycol (alkylene group having 2 to 4 carbon atoms, polymerization degree of 2 to 50), polyoxyalkylene polyol [polyoxyalkylene ether of the above trivalent to octavalent alcohol (alkylene group having 2 to 4 carbon atoms, polymerization degree) 2 to 100)], a mono(meth)acrylate of an alkyl (carbon number 1 to 4) ether of polyoxyalkylene glycol or polyoxyalkylene polyol [polyethylene glycol (number average molecular weight, hereinafter abbreviated as Mn: 100 to 300) mono. (Meth)acrylate, polypropylene glycol (Mn: 130 to 500) mono(meth)acrylate, methoxypolyethylene glycol (Mn: 110 to 310) (meth)acrylate and the like;

Examples of the phosphorus atom-containing monomer (g) include the following monomers (g1) to (g2).

Phosphoric acid ester group-containing monomer (g1):
(Meth)acryloyloxyalkyl (C2-4) phosphoric acid ester [(meth)acryloyloxyethyl phosphate and (meth)acryloyloxyisopropyl phosphate] and phosphoric acid alkenyl ester [vinyl phosphate, allyl phosphate, Propenyl phosphate, isopropenyl phosphate, butenyl phosphate, pentenyl phosphate, octenyl phosphate, decenyl phosphate, dodecenyl phosphate, etc.] and the like.

Phosphono group-containing monomer (g2):
(Meth)acryloyloxyalkyl (C2-4) phosphonic acid [(meth)acryloyloxyethylphosphonic acid, etc.] and alkenyl (C2-12) phosphonic acid [vinylphosphonic acid, allylphosphonic acid and octenylphosphonic acid] Etc.] etc. are mentioned.

Among (i), (g1) is preferable, (meth)acryloyloxyalkyl (C2-4) phosphate ester is more preferable, and (meth)acryloyloxyethyl phosphate is particularly preferable. Is.

The viscosity index (A) is a copolymer containing, in addition to the monomers (a) to (g), a monomer (h) having two or more unsaturated groups as a constituent monomer. It is preferable from the viewpoint of the improving effect and the low temperature viscosity of the lubricating oil composition.

Examples of the monomer (h) having two or more unsaturated groups include divinylbenzene, alkadienes having 4 to 12 carbon atoms (butadiene, isoprene, 1,4-pentadiene, 1,6-heptadiene and 1,7- Octadiene, etc.), (di)cyclopentadiene, vinylcyclohexene and ethylidene bicycloheptene, limonene, ethylene di(meth)acrylate, polyalkylene oxide glycol di(meth)acrylate, pentaerythritol triallyl ether, trimethylolpropane tri(meth)acrylate. Examples thereof include esters of unsaturated carboxylic acids having Mn of 500 or more and glycols and esters of unsaturated alcohols and carboxylic acids described in International Publication WO01/009242.

In addition to the monomers (a) to (h), (A) may have the following monomers (i) to (o) as constituent monomers.

Aliphatic hydrocarbon monomer (i):
Examples thereof include alkenes having 2 to 20 carbon atoms (ethylene, propylene, butene, isobutylene, pentene, heptene, diisobutylene, octene, dodecene, octadecene, etc.).

Alicyclic hydrocarbon-based monomer (j):
Examples thereof include cyclopentene, cyclohexene, cycloheptene, cyclooctene and pinene.

Aromatic hydrocarbon monomer (k):
Styrene, α-methylstyrene, vinyltoluene, 2,4-dimethylstyrene, 4-ethylstyrene, 4-isopropylstyrene, 4-butylstyrene, 4-phenylstyrene, 4-cyclohexylstyrene, 4-benzylstyrene, 4-chlorostyrene. Examples include chillbenzene, indene, 2-vinylnaphthalene and the like.

Vinyl ester, vinyl ether, vinyl ketones (l):
Vinyl ester of saturated fatty acid having 2 to 12 carbon atoms (vinyl acetate, vinyl propionate, vinyl butyrate, vinyl octanoate, etc.), alkyl, aryl or alkoxyalkyl vinyl ether having 1 to 12 carbon atoms (methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether) , Butyl vinyl ether, 2-ethylhexyl vinyl ether, phenyl vinyl ether, vinyl-2-methoxyethyl ether and vinyl-2-butoxyethyl ether, etc.) and C1-C8 alkyl or aryl vinyl ketones (methyl vinyl ketone, ethyl vinyl ketone and Phenyl vinyl ketone etc.) and the like.

Epoxy group-containing monomer (m):
Examples thereof include glycidyl (meth)acrylate and glycidyl (meth)allyl ether.

Halogen element-containing monomer (n):
Examples thereof include vinyl chloride, vinyl bromide, vinylidene chloride, (meth)allyl chloride, and styrene halides (dichlorostyrene etc.).

Esters of unsaturated polycarboxylic acids (o):
Alkyl, cycloalkyl or aralkyl ester of unsaturated polycarboxylic acid [C1-C8 alkyl diester of unsaturated dicarboxylic acid (maleic acid, fumaric acid, itaconic acid, etc.) (dimethyl maleate, dimethyl fumarate, diethyl maleate And dioctyl maleate)] and the like.

The proportion of (a) constituting (A) is preferably 1 to 20 based on the total number of moles of the monomers constituting (A) from the viewpoint of the effect of improving the viscosity index and the low temperature viscosity of the lubricating oil composition. Mol%, more preferably 2 to 16 mol%, particularly preferably 3 to 13 mol%, and most preferably 5 to 10 mol%.
The proportion of (b) that constitutes (A) is 80 to 95 mol% based on the total number of moles of the monomers that constitute (A), and it has an effect of improving the viscosity index and the low temperature viscosity of the lubricating oil composition. From the viewpoint, it is preferably 81 to 95 mol%, more preferably 82 to 95 mol%, and particularly preferably 84 to 94 mol%.
The respective proportions of (c) and (d) constituting (A) are based on the total number of moles of the monomers constituting (A) from the viewpoint of the effect of improving the viscosity index and the low temperature viscosity of the lubricating oil composition. It is preferably 0 to 10 mol %, more preferably 0.5 to 8 mol %, and particularly preferably 1.5 to 6 mol %.
The total ratio of (c) and (d) constituting (A) is based on the total number of moles of the monomers constituting (A) from the viewpoint of the effect of improving the viscosity index and the low temperature viscosity of the lubricating oil composition. It is preferably 0 to 15 mol %, more preferably 0.5 to 10 mol %, and particularly preferably 2 to 6 mol %.
The respective proportions of (e) to (g) constituting (A) are based on the total number of moles of the monomers constituting (A) from the viewpoint of the effect of improving the viscosity index and the low temperature viscosity of the lubricating oil composition. It is preferably 0 to 15 mol %, more preferably 0.5 to 10 mol %, and particularly preferably 2 to 6 mol %.
The respective proportions of (h) to (i) constituting (A) are based on the total number of moles of the monomers constituting (A) from the viewpoint of the effect of improving the viscosity index and the low temperature viscosity of the lubricating oil composition. It is preferably 0 to 15 mol %, more preferably 0.5 to 10 mol %, and particularly preferably 2 to 6 mol %.
The proportion of (j) constituting (A) is preferably 0.01 based on the total number of moles of the monomers constituting (A) from the viewpoint of the effect of improving the viscosity index and the low temperature viscosity of the lubricating oil composition. Is 0.1 to 0.1 mol %, more preferably 0.02 to 0.07 mol %, and particularly preferably 0.03 to 0.06 mol %.
The respective proportions of (k) to (o) constituting (A) are based on the total number of moles of the monomers constituting (A) from the viewpoint of the effect of improving the viscosity index and the low temperature viscosity of the lubricating oil composition. It is preferably 0 to 10 mol %, more preferably 0.5 to 8 mol %, and particularly preferably 1.5 to 6 mol %.

The molar ratio (a/b) of (a) and (b) constituting (A) is from 0.010 to 0.200, which is preferable from the viewpoint of the effect of improving the viscosity index and the low temperature viscosity of the lubricating oil composition. Is 0.030 to 0.195, more preferably 0.035 to 0.190, particularly preferably 0.040 to 0.185, and most preferably 0.045 to 0.180.

The weight average molecular weight of (A) (hereinafter abbreviated as Mw) is preferably 5,000 to 200,000, more preferably 10, from the viewpoint of the effect of improving the viscosity index and the shear stability of the lubricating oil composition. It is 000 to 120,000, particularly preferably 12,000 to 80,000, and most preferably 15,000 to 65,000.
If the Mw is less than 5,000, the effect of improving the viscosity-temperature characteristic and the effect of improving the viscosity index are small and the cost may increase. If the Mw exceeds 200,000, shear stability and ester oil base oil May have poor solubility and storage stability.

The number average molecular weight (hereinafter abbreviated as Mn) of (A) is preferably 2,500 or more, more preferably 5,000 or more, particularly preferably 10,000 or more, and most preferably 15,000. That is all. Further, it is preferably 200,000 or less, more preferably 80,000 or less, particularly preferably 60,000 or less, and most preferably 40,000 or less. When Mn is less than 2,500, the effect of improving the viscosity-temperature characteristic and the effect of improving the viscosity index are small and the cost may increase. When Mn exceeds 200,000, shear stability and ester oil base oil May have poor solubility and storage stability.

The ratio (Mw/PSSI) of Mw and PSSI of (A) is preferably 0.8×10 ⁴ or more, more preferably 1.0×10 ⁴ or more, and further preferably from the viewpoint of viscosity-temperature characteristics, that is, fuel economy. Is 1.5×10 ⁴ or more, particularly preferably 1.8×10 ⁴ or more, and most preferably 2.0×10 ⁴ or more. The Mn and Mw of (A) can be measured by gel permeation chromatography (hereinafter abbreviated as GPC) under the following conditions.
<Mn and Mw measurement conditions of (A)>
Device: "HLC-802A" [manufactured by Tosoh Corporation]
Column: "TSK gel GMH6" [manufactured by Tosoh Corporation] 2 Measuring temperature: 40°C
Sample solution: 0.25 wt% tetrahydrofuran solution Injection volume: 100 μl
Detector: Refractive index detector Reference substance: Standard polystyrene (TSK standard POLYSTYRENE) 12 points (molecular weight: 500, 1,050, 2,800, 5,970, 9,100, 18,100, 37,900, 96,400) , 190,000, 355,000, 1,090,000, 2,890,000) [manufactured by Tosoh Corporation]

The crystallization temperature of (A) is preferably −20° C. or lower, more preferably −30° C. or lower, particularly preferably −40° C. or lower, most preferably −50° C., from the viewpoint of low temperature viscosity of the lubricating oil composition. It is the following.
The crystallization temperature of (A) was measured using a differential scanning calorimeter “Unix (registered trademark) DSC7” (manufactured by PERKIN-ELMER) with 5 mg of (A) as a sample at an isothermal rate of 10° C./min. It is a crystallization temperature observed when cooled from 100°C to -60°C.

(A) can be obtained by a known production method, and specific examples thereof include a method of performing solution polymerization of the above monomer in a solvent in the presence of a polymerization catalyst.
Examples of the solvent include toluene, xylene, methyl ethyl ketone, ethyl acetate, ester oil and the like.
Polymerization catalysts include azo catalysts (azobisisobutyronitrile, azobisvaleronitrile, etc.), peroxide catalysts (benzoyl peroxide, cumyl peroxide, lauryl peroxide, etc.), and redox catalysts (benzoyl peroxide). And a mixture of tertiary amines). Further, if necessary, a known chain transfer agent (such as an alkylmercaptan having 2 to 20 carbon atoms) can be used.
The polymerization temperature is preferably 25 to 150°C, more preferably 50 to 130°C. In addition to the solution polymerization described above, (A) can be obtained by bulk polymerization, emulsion polymerization or suspension polymerization.
When (A) is a copolymer, the polymerization form may be either a random addition polymer or an alternating copolymer, and may be a graft copolymer or a block copolymer.

The viscosity index improver composition of the present invention comprises, in addition to (A), a (co)polymer (B) having a macromonomer (r) as a constituent monomer. Is preferable from the viewpoint of the effect of improving the viscosity index.
As the (co)polymer (B), in addition to the macromonomer (r), as the constituent monomer other than the macromonomer (r), from the viewpoint of the effect of improving the viscosity index, the above monomers (a) to (d). It is preferable that at least one of the above is used as a constituent monomer.

The macromonomer (r) is a macromonomer based on a hydrocarbon polymer, and is specifically an alkene having 2 to 10 carbon atoms [eg ethylene, propylene, normal butene, isobutene] and 2 to 10 carbon atoms. A hydroxyl group-containing (co)polymer obtained by introducing a hydroxyl group into only one end of a hydrocarbon polymer having one or more kinds of monomers selected from the group consisting of alkadienes (eg, butadiene, isoprene, etc.) as a constituent monomer, or Esterification reaction or amidation reaction of (meth)acrylic acid with an amino group-containing (co)polymer obtained by introducing an amino group into a hydrocarbon polymer only at one end, or transesterification with methyl (meth)acrylate, etc. It is a macromonomer obtainable by
When the hydrocarbon polymer has a double bond, a part or all of the double bond may be hydrogenated by hydrogenation.

The Mn of the hydrocarbon polymer is preferably 700 to 50,000 from the viewpoint of the effect of improving the viscosity index.
The Mn of (r) is preferably 700 to 50,000, more preferably 1,500 to 5,000 from the viewpoint of the effect of improving the viscosity index.

The ratio of (r) constituting (B) is preferably 2 to 60% by weight, and more preferably, based on the weight of (B), from the viewpoint of the effect of improving the viscosity index and the low temperature viscosity of the lubricating oil composition. Is 5 to 55% by weight, particularly preferably 10 to 50% by weight, and most preferably 15 to 45% by weight.

The Mw of (B) is preferably 100,000 to 1,000,000. The lower limit is more preferably 150,000 or more, further preferably 200,000 or more, particularly preferably 250,000 or more, and most preferably 300,000 or more. The upper limit is more preferably 800,000 or less, further preferably 700,000 or less, particularly preferably 600,000 or less, and most preferably 550,000 or less. When the Mw is less than 150,000, the effect of improving the viscosity-temperature characteristic and the effect of improving the viscosity index are small and the cost may increase. When the Mw exceeds 1,000,000, the shear stability and the ester oil group The solubility in oil and storage stability may deteriorate.

The Mn of (B) is preferably 50,000 or more, more preferably 80,000 or more, particularly preferably 100,000 or more, and most preferably 120,000 or more. Further, it is preferably 500,000 or less, more preferably 300,000 or less, particularly preferably 250,000 or less, and most preferably 200,000 or less. When Mn is less than 50,000, the effect of improving the viscosity-temperature characteristic and the effect of improving the viscosity index are small and the cost may increase. When Mn exceeds 500,000, shear stability and ester oil base oil May have poor solubility and storage stability.

The ratio of Mw to PSSI (Mw/PSSI) in (B) is preferably 0.8×10 ⁴ or more, more preferably 1.0×10 ⁴ or more, and further preferably from the viewpoint of temperature-temperature characteristics, that is, fuel economy. Is 1.5×10 ⁴ or more, particularly preferably 1.8×10 ⁴ or more, and most preferably 2.0×10 ⁴ or more. The Mn and Mw of (B) can be measured under the same conditions as the Mn and Mw of (A).

The ratio (Mw/Mn) of Mw and Mn of (B) is preferably 0.5 or more, preferably 1.0 or more, more preferably 1.5 or more, further preferably 2.0 or more, and particularly It is preferably 2.1 or more. Further, Mw/Mn is preferably 6.0 or less, more preferably 4.0 or less, further preferably 3.5 or less, and particularly preferably 3.0 or less. If Mw/Mn is less than 0.5 or exceeds 6.0, the viscosity-temperature characteristic may be deteriorated, that is, the fuel economy may be deteriorated.

Like (A), (B) can be obtained by a known production method.

When using (A) and (B) together, the amount of (B) used is preferably 0.01 to 30% by weight, and more preferably 0, from the viewpoint of low temperature viscosity, based on the weight of (A). 0.01 to 20% by weight, particularly preferably 0.01 to 10% by weight.

In the viscosity index improver composition of the present invention, in addition to (A) and (B), an alkyl (meth)acrylic acid ester (co)polymer (C) other than (A) may be used in combination.

(C) is not particularly limited as long as it is an alkyl (meth)acrylic acid ester (co)polymer other than (A), but is a (meth)acrylic acid alkyl ester having a linear alkyl group having 1 to 18 carbon atoms. Examples thereof include (co)polymers.
Specific examples of (C) include a copolymer of n-octadecyl methacrylate/n-dodecyl methacrylate (molar ratio 10 to 30/90 to 70), n-tetradecyl methacrylate/n-dodecyl methacrylate (molar ratio 10). -30/90-70) copolymer, n-hexadecyl methacrylate/n-dodecyl methacrylate/methyl methacrylate (molar ratio 20-40/55-75/0-10) copolymer and n-dodecyl acrylate /N-dodecyl methacrylate (molar ratio 10 to 40/90 to 60) copolymer and the like can be mentioned, and these may be used alone or in combination of two or more kinds.

When (A) and (C) are used in combination, the amount of (C) used is preferably 0.01 to 30% by weight, and more preferably 0, from the viewpoint of low temperature viscosity, based on the weight of (A). 0.01 to 20% by weight, particularly preferably 0.01 to 10% by weight.

It is preferable that (A) be dissolved in a lubricating base oil of API group V having a kinematic viscosity at 100° C. of 1.0 to ^2.5 mm ² /s. Here, "dissolve" means that 100 parts by weight of (A) is dissolved in 100 parts by weight of ester oil base oil, the appearance is uniform, and there is no insoluble matter of (A).

(A) is a spectrum obtained by nuclear magnetic resonance analysis (13C-NMR), in which the total area M1 of peaks between chemical shifts 29-31 ppm and the peak between chemical shifts 67-73 ppm relative to the total area of all peaks. The ratio M1/M2 of the total area M2 is 1.0 or more.

M1/M2 needs to be 1.0 or more, preferably 2.0 or more, more preferably 3.0 or more, particularly preferably 4.0 or more, and most preferably 5.0 or more. Further, M1/M2 is preferably 35 or less, more preferably 32 or less, particularly preferably 30 or less, and most preferably 27 or less. If M1/M2 is less than 1.0, not only the required fuel economy cannot be obtained, but also the low temperature viscosity characteristics may deteriorate. When M1/M2 exceeds 27, the required fuel economy may not be obtained, and the solubility and storage stability may be deteriorated.

(A) is a spectrum obtained by nuclear magnetic resonance analysis (13C-NMR), in which the total area M3 of peaks between chemical shifts of 10 to 20 ppm and the peak between chemical shifts of 25 to 35 ppm with respect to the total area of all peaks. The ratio M3/M4 of the total area M4 is 0.20 or more.

M3/M4 needs to be 0.20 or more, preferably 0.3 or more, more preferably 0.4 or more, particularly preferably 0.5 or more, and most preferably 0.6 or more. Further, M3/M4 is preferably 5.0 or less, more preferably 3.0 or less, particularly preferably 2.0 or less, and most preferably 1.5 or less. If M3/M4 is less than 0.20, not only the required fuel economy cannot be obtained, but also the low temperature viscosity characteristics may deteriorate. If M3/M4 exceeds 5.0, the required fuel economy may not be obtained, and the solubility and storage stability may deteriorate.

(A) is a spectrum obtained by nuclear magnetic resonance analysis (13C-NMR), in which the total area M5 of peaks between chemical shifts 44 to 46 ppm and the peak between chemical shifts 63 and 72 ppm with respect to the total area of all peaks. The ratio M5/M6 of the total area M6 is 0.20 or more.

M5/M6 needs to be 0.20 or more, preferably 0.3 or more, more preferably 0.4 or more, particularly preferably 0.5 or more, and most preferably 0.6 or more. Further, M5/M6 is preferably 3.0 or less, more preferably 2.0 or less, particularly preferably 1.0 or less, and most preferably 0.8 or less. If M5/M6 is less than 0.20, not only the required fuel economy cannot be obtained, but also the low temperature viscosity characteristics may deteriorate. If M5/M6 exceeds 3.0, the required fuel economy may not be obtained, and the solubility and storage stability may deteriorate.

The nuclear magnetic resonance analysis (13C-NMR) spectrum is obtained from the polymer obtained by separating the diluent oil by rubber membrane dialysis or the like when (A) contains the diluent oil.

The total area (M1) of peaks between chemical shifts of 29 to 31 ppm with respect to the total area of all peaks was measured by 13C-NMR, and the total area of the integrated intensity of all carbons was calculated from the side chain of poly(meth)acrylate. It means the percentage of integrated intensity derived from a particular ethylene structure. Chemical shifts relative to the total area of all peaks The total area of the peaks between 67-73 ppm (M2) is the specific ether of the poly(meth)acrylate side chain relative to the total integrated intensity of all carbons measured by 13C-NMR. It means the ratio of the integrated intensity derived from the structure.
The total area of the peaks (M3) between 10-20 ppm chemical shifts relative to the total area of all peaks is the specific methyl of the poly(meth)acrylate side chain relative to the total integrated intensity of all carbons measured by 13C-NMR. It means the ratio of the integrated intensity derived from the structure.
Chemical shifts relative to the total area of all peaks The total area of the peaks between 25-35 ppm (M4) is the specific methylene of the poly(meth)acrylate side chain relative to the total integrated intensity of all carbons measured by 13C-NMR. It means the ratio of the integrated intensity derived from the structure.
The total area of the peaks (M5) between 44-46 ppm chemical shift relative to the total area of all peaks is the specific methine of the poly(meth)acrylate side chain relative to the total integrated intensity of all carbons measured by 13C-NMR. It means the ratio of the integrated intensity derived from the structure.
Chemical shifts relative to the total area of all peaks The total area of the peaks between 63-72 ppm (M5) is the oxygen atom of the poly(meth)acrylate side chain relative to the total integrated intensity of all carbons measured by 13C-NMR. It means the ratio of integrated intensity derived from adjacent carbon atoms.

M1/M2 means the ratio of the specific methylene structure and the specific ether structure of the poly(meth)acrylate side chain, but other methods may be used as long as equivalent results can be obtained. In the 13C-NMR measurement, 0.1 g of a sample diluted with 2 ml of deuterated chloroform was used as a sample, the measurement temperature was room temperature, the resonance frequency was 100 MHz, and the decoupling method with a reverse gate was used. It was used.

By the above analysis,
(A) Sum of integrated intensities of chemical shift of about 10-74 ppm (total of intensities attributable to all carbons of hydrocarbon), and (b) Sum of integrated intensities of chemical shift of 29-31 ppm (for a specific β-branched structure). (Sum of integrated intensity due to) and (c) sum of integrated intensity of chemical shift 67-73 ppm (sum of integrated intensity due to specific linear structure)
(D) Sum of integrated intensities of chemical shifts of 10-20 ppm (sum of integrated intensities due to a specific β-branched structure), and (e) Sum of integrated intensities of chemical shifts of 29-31 ppm (due to specific linear structures) Sum of integrated intensity)
(F) Sum of integrated intensities of chemical shift 44-46 ppm (sum of integrated intensities due to specific β-branched structure), and (g) Sum of integrated intensities of chemical shift 63-72 ppm (due to specific linear structure) Sum of integrated intensity)
Was measured, and the ratio (%) of (b) when (a) was set to 100% was calculated as M1. Similarly, the ratio (%) of (c), (d), (e), (f), and (g) when (a) is set to 100% is calculated, and M2, M3, M4, and M5, respectively. It was set to M6.

The shear stability index (hereinafter referred to as PSSI) of (A) is preferably 20 or less, more preferably 15 or less, further preferably 10 or less, and particularly preferably 8 or less. Further, it is preferably 0.1 or more, more preferably 0.5 or more, further preferably 1 or more, and particularly preferably 2 or more. When the shear stability index is less than 0.1, the viscosity index improving effect may be small and the cost may increase, and when the shear stability index exceeds 20, the shear stability and storage stability may be deteriorated. is there.

The ratio (Mw/Mn) of Mw and Mn of (A) is preferably 1.0 or more, preferably 1.2 or more, more preferably 1.3 or more, further preferably 1.5 or more, and particularly It is preferably 1.6 or more. Further, Mw/Mn is preferably 6.0 or less, more preferably 4.0 or less, further preferably 3.0 or less, and particularly preferably 2.0 or less. When Mw/Mn is less than 1.0 or exceeds 6.0, the viscosity-temperature characteristic may be deteriorated, that is, the fuel economy may be deteriorated.

The content of (A) in the lubricating oil composition of the present invention is preferably 0.01 to 37% by weight, more preferably 0.2 to 35% by weight, and even more preferably the total amount of the lubricating oil composition. 0.5 to 33% by weight, particularly preferably 1 to 30% by weight. When the content of (A) is less than 0.01% by weight, the effect of improving the viscosity index and the effect of reducing the product viscosity are reduced, and there is a possibility that the fuel economy cannot be improved.

The ester oil base oil of the present invention has a kinematic viscosity at 100° C. of 1.0 to 2.5 mm ² /s.

The ester oil base oil according to the present invention is not particularly limited as long as it satisfies the above conditions. Specifically, among monoester-based lubricating base oils, diester-based lubricating base oils, polyester-based lubricating base oils and the like, ester-based base oils satisfying the above conditions can be used.

The upper limit of 100 ° C. kinematic viscosity of the ester base oil of the invention must be less than or equal 2.5 mm ² / s, preferably 2.25 mm ² / s or less, more preferably 2.00 mm ² / s or less, more preferably 1.75 mm ² / s or less, particularly preferably 1.50 mm ² / s or less, and most preferably not more than 1.35 mm ² / s. On the other hand, the lower limit of the 100° C. kinematic viscosity needs to be 1.0 mm ² /s or more, preferably 1.02 mm ² /s or more, and more preferably 1.05 mm ² /s or more, more preferably 1.07 mm ² / s or more, particularly preferably 1.1 mm ² / s or more. The kinematic viscosity at 100° C. as used herein refers to the kinematic viscosity at 100° C. specified in ASTM D-445. If the 100 ° C. kinematic viscosity of the ester base oil component exceeds 2.5 mm ² / s, the low temperature viscosity characteristics are deteriorated and no sufficient fuel savings are obtained in the case of less than 1.0 mm ² / s Results in inferior lubricity due to insufficient formation of an oil film at the lubrication site, and also causes large evaporation loss of the lubricating oil composition.

The upper limit of the kinematic viscosity at 40 ° C. of the ester base oil of the present invention is preferably 7.0 mm ² / s or less, more preferably 6.50 mm ² / s or less, more preferably 6.0 mm ² / s or less, particularly preferably 5.50 mm ² / s or less, and most preferably not more than 5.0 mm ² / s. On the other hand, the lower limit of the 40 ° C. kinematic viscosity is preferably 2.5 mm ² / s or more, more preferably 2.55 mm ² / s or higher, more preferably 2.6 mm ² / s or more, particularly preferably 2.65 mm ² /S or more, and most preferably 2.7 mm ² /s or more. If the 40 ° C. kinematic viscosity of the ester base oil component exceeds 4.0 mm ² / s, the worse the low temperature viscosity characteristics and may not sufficient fuel economy is obtained, 2.5 mm ² / s When it is less than the above range, the oil film is not sufficiently formed at the lubricated portion, so that the lubricity is poor, and the evaporation loss of the lubricating oil composition may be large.

The SP value of the ester oil base oil is preferably 8.0 to 9.5 (cal/cm ³ ) ^1/2 , and more preferably 8.2 to 9.4 (cal) from the viewpoint of the effect of improving the viscosity index. /Cm ³ ) ^1/2 , more preferably 8.4 to 9.3 (cal/cm ³ ) ^1/2 .

The density (ρ15) at 15° C. of the ester oil base oil according to the present invention depends on the viscosity grade of the lubricating base oil component, but is not more than the value of ρ represented by the following formula (A), that is, ρ15 It is preferable that ≦ρ.
ρ=0.0025×kv100+0.816 (A)
[In the formula, kv100 represents the kinematic viscosity (mm ² /s) of the lubricating base oil component at 100°C. ]

When ρ15>ρ, the viscosity-temperature characteristic and the heat/oxidation stability, as well as the volatility prevention property and the low-temperature viscosity characteristic tend to be deteriorated, which may deteriorate fuel economy.

Specifically, the density (ρ15) of the ester base oil according to the present invention at 15° C. is preferably 0.880 g/cm ³ or less, more preferably 0.875 g/cm ³ or less, further preferably 0.870 g. /Cm ³ or less, particularly preferably 0.860 g/cm ³ or less.

The density at 15° C. in the present invention means the density measured at 15° C. according to JIS K 2249-1:2011.

The pour point of the ester base oil according to the present invention is preferably -10°C or lower, more preferably -12.5°C or lower, and further preferably -15°C or lower. When the pour point exceeds the upper limit value, the low temperature fluidity of the entire lubricating oil tends to decrease. The pour point in the present invention means the pour point measured according to JIS K 2269:1987.

The viscosity index of the lubricating oil composition of the present invention is preferably 400 to 800, more preferably 450 to 750, further preferably 470 to 720, particularly preferably 500 to 700, and most preferably 520 to 680. When the viscosity index of the lubricating oil composition of the present invention is less than 400, it may be difficult to improve fuel economy and further it may be difficult to reduce the low temperature viscosity at -40°C. is there. Further, when the viscosity index of the lubricating oil composition of the present invention exceeds 800, the low temperature fluidity may be deteriorated, and further problems due to poor solubility of the additive may occur.

The kinematic viscosity of the lubricating oil composition of the present invention at 100° C. is preferably 4.2 to 5.7 mm ² /s from the viewpoint of low temperature viscosity. The 100 limit ℃ kinematic viscosity is more preferably 5.6 mm ² / s or less, more preferably 5.5 mm ² / s or less, particularly preferably 5.4 mm ² / s or less, and most preferably 5.3 mm ² / s It is the following. On the other hand, in view of the lower limit of the viscosity index improving effect and evaporation properties of the 100 ° C. kinematic viscosity, more preferably 4.3 mm ² / s or higher, more preferably 4.4 mm ² / s or more, particularly preferably 4.5 mm ² /S or more. If the kinematic viscosity is less than 4.2 mm 2 / ^s is at 40 ° C., there is insufficient lubricity may give low temperature viscosity and sufficient fuel efficiency performance required in the case of more than 5.7 mm 2 / ^s It may not be possible.

The kinematic viscosity of the lubricating oil composition of the present invention at 40° C. is preferably 4 to 25 mm ² /s. The upper limit of the 40° C. kinematic viscosity is more preferably 22 mm ² /s or less, further preferably 20 mm ² /s or less, particularly preferably 18 mm ² /s or less, still more preferably 16 mm ² /s or less, most preferably 14 mm ² /S or less. On the other hand, the lower limit of the kinematic viscosity at 40° C. is more preferably 5 mm ² /s or more, further preferably 6 mm ² /s or more, particularly preferably 7 mm ² /s or more, and particularly preferably 8 mm ² /s or more. If the kinematic viscosity at 40° C. is less than 4 mm ² /s, lubricity may be insufficient, and if it exceeds 25 mm ² /s, the required low temperature viscosity and sufficient fuel saving performance may not be obtained. is there.

The upper limit of the HTHS viscosity at 100° C. of the lubricating oil composition of the present invention is preferably 6.0 mPa·s or less, more preferably 5.5 mPa·s or less, and further preferably 5.3 mPa·s or less. Yes, particularly preferably 5.0 mPa·s or less, and most preferably 4.5 mPa·s or less. Further, the lower limit of the HTHS viscosity at 100° C. is preferably 3.0 mPa·s or more, more preferably 3.5 mPa·s or more, further preferably 3.8 mPa·s or more, particularly preferably 4.0 mPa·s. s or more, and most preferably 4.2 mPa·s or more. The HTHS viscosity at 100° C. as used herein refers to a high temperature high shear viscosity at 100° C. defined by ASTM D4683. When the HTHS viscosity at 100° C. is less than 3.0 mPa·s, high evaporability may result in insufficient lubricity, and when it exceeds 6.0 mPa·s, necessary low temperature viscosity and sufficient fuel economy Performance may not be obtained.

The upper limit of the HTHS viscosity at 150° C. of the lubricating oil composition of the present invention is preferably 3.5 mPa·s or less, more preferably 3.0 mPa·s or less, and further preferably 2.8 mPa·s or less. Yes, and particularly preferably 2.7 mPa·s or less. The lower limit of the HTHS viscosity at 150° C. is preferably 2.0 mPa·s or more, more preferably 2.3 mPa·s or more, further preferably 2.4 mPa·s or more, particularly preferably 2.5 mPa·s or more. , And most preferably 2.6 mPa·s or more. The HTHS viscosity at 150° C. as used herein refers to a high temperature high shear viscosity at 150° C. defined by ASTM ASTM D4683. If the HTHS viscosity at 150° C. is less than 2.0 mPa·s, high evaporability may result in insufficient lubricity, and if it exceeds 3.5 mPa·s, necessary low temperature viscosity and sufficient fuel economy Performance may not be obtained.

Further, in the lubricating oil composition of the present invention, it is preferable that the ratio of the HTHS viscosity at 100° C. to the HTHS viscosity at 150° C. satisfies the condition represented by the following formula (C).
HTHS (100°C)/HTHS (150°C) ≤ 2.04 (C)
[In formula, HTHS (100 degreeC) shows HTHS viscosity in 100 degreeC, and HTHS (150 degreeC) shows HTHS viscosity in 150 degreeC. ]

The upper limit of HTHS (100° C.)/HTHS (150° C.) is preferably 2.04 or less, more preferably 2.00 or less, still more preferably 1.98 or less, particularly preferably 1.80 or less, and most preferably It is preferably 1.70 or less. If HTHS (100° C.)/HTHS (150° C.) exceeds 2.04, sufficient fuel saving performance or low temperature characteristics may not be obtained. The lower limit of HTHS (100° C.)/HTHS (150° C.) is preferably 0.50 or more, more preferably 0.70 or more, still more preferably 1.00 or more, and particularly preferably 1.30 or more. When HTHS (100° C.)/HTHS (150° C.) is less than 0.50, the cost of the base material may be significantly increased and the solubility of the additive may not be obtained.

The content of the viscosity index improver in the lubricating oil composition of the present invention is preferably 1 to 70% by weight in terms of the weight of (A) in the viscosity index improver, based on the weight of the ester oil base oil. Is.
When the lubricating oil composition is used as an engine oil, it preferably contains 2 to 30% by weight of (A).
When the lubricating oil composition is used as a gear oil, it preferably contains 10 to 70% by weight of (A).
When the lubricating oil composition is used as an automatic transmission oil (ATF, belt-CVTF, etc.), it is preferable to contain 10 to 70% by weight of (A).
When the lubricating oil composition is used as a traction oil, it preferably contains 0.5 to 20% by weight of (A).

The upper limit of shear stability (hereinafter abbreviated as SS) of the lubricating oil composition of the present invention is preferably 10% or less, and more preferably 9% or less from the viewpoint of reducing friction and preventing wear after running for a long time. It is more preferably 8% or less, particularly preferably 7% or less, and most preferably 6% or less. On the other hand, from the viewpoint of reducing the amount of the viscosity index improver used, the lower limit of SS is more preferably 0.5% or more, further preferably 1% or more, particularly preferably 1.5% or more. If the SS is more than 10%, there is a possibility that inter-wear, seizure and sufficient fuel saving performance may not be obtained.

The low temperature viscosity at −40° C. of the lubricating oil composition of the present invention is preferably 5,000 mPa·s or less from the viewpoint of initial startability of the engine. It is more preferably 4,500 mPa·s or less, still more preferably 4,000 mPa·s or less.

The lubricating oil composition of the present invention is a gear oil (differential oil, industrial gear oil, etc.), MTF, transmission oil [ATF and belt-CVTF, etc.], traction oil (toroidal-CVTF, etc.), shock absorber oil, power steering. It is preferably used as oil, hydraulic oil (hydraulic oil for construction machinery, hydraulic oil for industrial use, etc.). Of these, preferred are gear oils, MTFs, transmission oils and traction oils, more preferred are differential oils, MTFs, ATFs and belt-CVTFs, and particularly preferred are MTFs, ATFs and belt-CVTFs. ..

The lubricating oil composition of the present invention may contain various additives. Examples of the additive include additives such as a dispersant, a detergent, an antioxidant, an oiliness improver, a pour point depressant, a friction and wear modifier, an extreme pressure agent, an antifoaming agent, a demulsifier and a corrosion inhibitor. To be These additives may be used alone or in combination of two or more.

Examples of the dispersant include succinimides (bis- or mono-polybutenylsuccinimides), Mannich condensation products, borates, and the like.

Detergents include basic, overbased or neutral metal salts [overbased or alkaline earth metal salts of sulfonates (petroleum sulfonate, alkylbenzene sulfonate, alkylnaphthalene sulfonate, etc.)], salicylates , Phenates, naphthenates, carbonates, phosphonates and mixtures thereof.

Examples of the antioxidant include ashless antioxidants such as phenol-based and amine-based antioxidants, and metal-based antioxidants such as zinc-based, copper-based and molybdenum-based antioxidants.

Examples of the phenolic antioxidant include 4,4′-methylenebis(2,6-di-tert-butylphenol), 4,4′-bis(2,6-di-tert-butylphenol), 4,4′. -Bis(2-methyl-6-tert-butylphenol), 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 4,4'-butylidene bis(3-methyl-6-tert-butylphenol), 4,4'-isopropylidene bis(2,6-di-tert-butylphenol), 2,2'-methylenebis(4-methyl-6) -Nonylphenol), 2,2'-isobutylidenebis(4,6-dimethylphenol), 2,2'-methylenebis(4-methyl-6-cyclohexylphenol), 2,6-di-tert-butyl-4 -Methylphenol, 2,6-di-tert-butyl-4-ethylphenol, 2,4-dimethyl-6-tert-butylphenol, 2,6-di-tert-α-dimethylamino-p-cresol, 2, 6-di-tert-butyl-4-(N,N-dimethylaminomethylphenol), 4,4'-thiobis(2-methyl-6-tert-butylphenol), 4,4'-thiobis(3-methyl- 6-tert-butylphenol), 2,2′-thiobis(4-methyl-6-tert-butylphenol), bis(3-methyl-4-hydroxy-5-tert-butylbenzyl) sulfide, bis(3,5- Di-tert-butyl-4-hydroxybenzyl) sulfide, 2,2′-thio-diethylenebis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], tridecyl-3-(3 ,5-Di-tert-butyl-4-hydroxyphenyl)propionate, pentaerythrityl-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octyl-3-(3,3. 5-di-tert-butyl-4-hydroxyphenyl)propionate, stearyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, octyl-3-(3-methyl-5-di-tert) -Butyl-4-hydroxyphenyl)propionate and the like. You may use these in mixture of 2 or more types.

Examples of the oiliness improver include long-chain fatty acids and their esters (such as oleic acid and oleic acid esters), long-chain amines and their amides (such as oleylamine and oleylamide), and the like.

Examples of the pour point depressant include a long chain alkyl methacrylate (alkyl group having 12 to 18 carbon atoms) copolymer.

Examples of the friction and wear modifier include molybdenum-based and zinc-based compounds (molybdenum dithiophosphate, molybdenum dithiocarbamate, zinc dialkyldithiophosphate, etc.) and the like.

Examples of the extreme pressure agent include sulfur compounds (mono- or disulfides, sulfoxides and sulfur phosphides), phosphides and chlorine compounds (chlorinated paraffins, etc.).

Examples of the defoaming agent include silicone oil, metallic soap, fatty acid ester and phosphate compound.

Examples of the demulsifier include quaternary ammonium salt (tetraalkylammonium salt and the like), sulfated oil and phosphate (polyoxyethylene-containing nonionic surfactant phosphate and the like) and the like.

Examples of the corrosion inhibitor include nitrogen atom-containing compounds (benzotriazole and 1,3,4-thiodiazolyl-2,5-bisdialkyldithiocarbamate).

Only one of these additives may be used, or two or more additives may be used as required. A mixture of these additives may be called a performance additive.

The method for producing a lubricating oil composition in the present application is a method for producing a lubricating oil composition including a step of mixing a viscosity index improver and a lubricating base oil. Further, it may include a step of mixing various additives and the like.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited thereto.

<Examples 1 to 10 and Comparative Examples 1 to 4>
100 parts by weight of the base oil shown in Table 1 was put into a reaction vessel equipped with a stirrer, a heating/cooling device, a thermometer, a dropping funnel, a nitrogen introducing tube and a decompressor, and another glass beaker shown in Table 1 was charged. Monomer, dodecyl mercaptan as a chain transfer agent, 0.5 part by weight of 2,2'-azobis(2,4-dimethylvaleronitrile) and 0.2 parts of 2,2'-azobis(2-methylbutyronitrile) Part by weight was added, and the mixture was stirred and mixed at 20° C. to prepare a monomer solution, which was then added to the dropping funnel. After the gas phase of the reaction vessel was replaced with nitrogen, the monomer solution was added dropwise over 2 hours while maintaining the internal system temperature at 70 to 85°C under a closed condition, and aged at 85°C for 2 hours from the end of the addition. After that, the temperature of the mixture was raised to 120 to 130° C., unreacted monomers were removed under reduced pressure (0.027 to 0.040 MPa) at the same temperature for 2 hours, and copolymers (A1) to (A10) were obtained. Comparative viscosity index improver compositions (R1) to (R10) containing copolymers (H1) to (H4) and comparative viscosity index improvers (S1) to (S4) were obtained. The SP values and the dispersity of the SP values of the obtained copolymers (A1) to (A10) and (H1) to (H4) were calculated by the above method, and Mw was measured by the above method. Further, the low temperature storage stability of the viscosity index improver compositions (R1) to (R10) and (S1) to (S4) was evaluated by the following method. The results are shown in Table 1.

<Evaluation method of low temperature storage stability of viscosity index improver composition>
The viscosity index improver compositions (R1) to (R10) and (S1) to (S4) were added to the base oil in an amount of 10% by weight based on the weight of the base oil to homogenize them, and the appearance after storage at -25°C for 24 hours was visually observed. The low temperature storage stability was evaluated according to the following evaluation criteria.
[Evaluation criteria]
◯: The appearance is uniform and there is no insoluble matter of the copolymer. x: The appearance is not uniform and insoluble matter of the copolymer is observed.

The compositions of the monomers (a) to (g) shown in Tables 1 and 2 are as described below.
(A-1): 2-tetradecyl methacrylate octadecyl methacrylate (ISOFOL32 made by Sasol and methacrylic acid esterified product) (C32)
(A-2): 2-tetradecylicosyl methacrylate (34 carbon atoms)
(A-3): 2-hexadecylicosyl methacrylate (36 carbon atoms)
(B-1): Methyl methacrylate (C1)
(B-2): n-butyl methacrylate (carbon number 4)
(C-1): 2-octyldodecyl methacrylate (20 carbon atoms)
(C-2): 2-n-decyl tetradecyl methacrylate (24 carbon atoms)
(C-1): 2-dodecyl hexadecyl methacrylate (28 carbon atoms)
(D-1): n-dodecyl methacrylate (C12)
(D-2): n-tetradecyl methacrylate (14 carbon atoms)
(D-3): n-hexadecyl methacrylate (C16)
(D-4): n-octadecyl methacrylate (18 carbon atoms)
(E-1): N,N-dimethylaminoethyl methacrylate (f-1): hydroxyethyl methacrylate (g-1): methacryloyloxyethyl phosphate

<Production Example 1>
Production of diester oil base oil (base oil E5) In a reaction vessel equipped with a stirrer, a thermometer, a nitrogen introduction tube, and a water fractionation receiver with a cooling tube, 255.0 parts of neopentyl glycol and 776.9 octanoic acid were added. And 48 parts of xylene were charged and the temperature was raised to 200° C. under a nitrogen atmosphere. The esterification reaction was carried out for about 10 hours while removing the produced water distilled out with the theoretical amount of produced water (88 g) as the target. After completion of the reaction, excess acid and xylene were removed by distillation to obtain an esterified crude product. Next, the obtained esterified crude product was transferred to an eggplant-shaped flask equipped with a Vigreux fractionating tube, and distilled at 220° C. under reduced pressure. The first distillate and the second distillate were removed by 15% by volume by vacuum distillation, and the middle distillate was collected. Nakatome was a diester (base oil E5): neopentyl glycol di-n-octanoate (molecular weight 356), and the total acid value of (base oil E5) was 0.01 mgKOH/g.

<Production Example 2>
4400 parts by weight of base oil E1 as an ester oil base oil, 20 parts of hydrogenated polybutadiene methacrylate (Mn: 7,000), a monomer were placed in a reaction vessel equipped with a stirrer, a heating/cooling device, a thermometer and a nitrogen introducing pipe. (B-2) 65 parts, monomer (d-1) 10 parts, monomer (d-2) 5 parts Compound 100 parts by weight, 2,2'-azobis(2-methylbutyronitrile) After adding 0.15 part by weight and performing nitrogen substitution (gas phase oxygen concentration 100 ppm), the temperature was raised to 76° C. under agitation and stirring, and a polymerization reaction was carried out at the same temperature for 4 hours. After raising the temperature to 120 to 130° C., the unreacted monomer is removed at reduced pressure (0.027 to 0.040 MPa) at the same temperature for 2 hours, and the viscosity index improver containing the copolymer (B1). A composition (T1) (Mw: 450,000) was obtained.

<Examples 11 to 20, Comparative Examples 5 to 8 (evaluation of lubricating oil composition)>
In a stainless steel container equipped with a stirrer, the performance additives [metals as described in Table 3 are added so that the resulting lubricating oil composition has a kinematic viscosity of 100° C. of 4.50±0.02 (mm ² /s). Type (TBN 300mgKOH/g calcium sulfonate type) detergent, ashless residue (succinimide), friction modifier (oleylamide), antiwear agent (phosphoric acid), antioxidant (diphenylamine), metal deactivation Agent (thiadiazole) and sulfur-based additive (sulfurized ester)], and viscosity index improver compositions (R1) to (R10), (S1) to (S4), (T1), and a base oil, respectively. Were mixed to obtain lubricating oil compositions (V1) to (V10) and (W1) to (W4).
Lubricating oil compositions (V1) to (V10), (W1) to (W4) were measured for viscosity index, kinematic viscosity at 40°C, viscosity index, and low temperature viscosity (-40°C) by the following methods. The results are shown in Table 3.

<Examples 20 to 30, Comparative Examples 9 to 12 (evaluation of lubricating oil composition)>
In a stainless steel container equipped with a stirrer, the lubricating oil composition obtained was treated with the performance additive as described in Table 4 so that the kinematic viscosity at 100° C. was 5.50±0.02 (mm ² /s). , Viscosity index improver compositions (R1) to (R10), (S1) to (S4) and (T1), respectively, and a base oil are mixed, and lubricating oil compositions (V11) to (V20) and (W5). )-(W8) were obtained.
Lubricating oil compositions (V11)-(V20), (W5)-(W8) viscosity index, kinematic viscosity at 40°C, viscosity index, HTHS viscosity and low temperature viscosity (-40°C) were measured by the following methods. The results are shown in Table 4.

The physical properties of the base oils shown in Tables 1 to 4 are as described below.
(Base oil E1): Monoester oil base oil (M fine ester EHO-100 manufactured by Miyoshi Yushi Co., Ltd., kinematic viscosity at 100° C. 1.1 mm ² /s, kinematic viscosity at 40° C.: 2.7 mm ² /s, viscosity index: not calculable. , SP value 8.45)
(Base oil E2): Monoester oil base oil (M fine ester CO-108 manufactured by Miyoshi Yushi Co., Ltd., kinematic viscosity at 100° C. 1.1 mm ² /s, kinematic viscosity at 40° C.: 2.9 mm ² /s, viscosity index: not calculable. , SP value 8.54)
(Base oil E3): Diester oil base oil (DBA manufactured by Daihachi Chemical Industry, 100° C. kinematic viscosity: 1.41 mm ² /s, 40° C. kinematic viscosity: 3.58 mm ² /s, viscosity index: non-calculatable, SP value 9.26)
(Base oil E4): Diester oil base oil (DBS manufactured by Daihachi Chemical Industry, 100° C. kinematic viscosity: 2.04 mm ² /s, 40° C. kinematic viscosity: 5.72 mm ² /s, viscosity index: 182, SP value 9 19)
(Base oil E5): Diester oil base oil (Production Example 1, 100° C. kinematic viscosity: 2.22 mm ² /s, 40° C. kinematic viscosity: 7.00 mm ² /s, viscosity index: 132, SP value 8.93)
(Base oil K): Highly refined mineral base oil (YUBASE-2 manufactured by SK, kinematic viscosity at 100° C. 2.2 mm ² /s, kinematic viscosity at 40° C.: 7.4 mm ² /s, viscosity index: 99, SP value 8 .30)

<Calculation method of viscosity index of lubricating oil composition>
Kinematic viscosities at 40° C. and 100° C. were measured by the method of ASTM D 445 and calculated by the method of ASTM D 2270.

<Measurement method and calculation method of shear stability of lubricating oil composition>
According to the procedure similar to the method of JASO M347-2007, the test time was changed from 1 hour to 10 hours, and the measurement was performed. The calculation of shear stability was performed by the method of JASO M347-2007.

<Method for measuring low temperature viscosity (-40°C) of lubricating oil composition>
It was measured at -40°C by the method of ASTM D 2983.

As is clear from the results of Table 3, the lubricating oil compositions (Examples 11 to 20) containing the viscosity index improver of the present invention have a high effect of improving the viscosity index and a low temperature viscosity. Although both are satisfied, the lubricating oil compositions of Comparative Examples 5 to 8 are inferior in the effect of at least one of them. Further, as is clear from the results in Table 4, the lubricating oil compositions (Examples 21 to 30) containing the viscosity index improver of the present invention similarly have a high viscosity index improving effect and a low temperature viscosity. Although both of the effects are low, the lubricating oil compositions of Comparative Examples 5 to 8 are inferior in at least one of the effects.

The lubricating oil composition containing the viscosity index improver of the present invention is a drive system lubricating oil (MTF, differential gear oil, ATF, belt-CVTF, etc.), hydraulic oil (machine hydraulic oil, power steering oil and shock). It is suitable as absorber oil, engine oil (for gasoline and diesel, etc.) and traction oil.

Claims (10)

A copolymer in which the monomer (a) represented by the following general formula (1) and a (meth)acrylic acid linear alkyl ester (b) having a linear alkyl group having 1 to 4 carbon atoms are essential constituent monomers. The polymer (A) and an ester oil base oil having a kinematic viscosity at 100° C. of 1.0 to 2.5 mm ² /s and a kinematic viscosity at 40° C. of 2.5 to 7.0 mm ² /s. A lubricating oil composition containing a viscosity index improver composition comprising (A), wherein (A) is 80 to 80 (b) based on the number of moles of the constituent monomer of (A) as a constituent monomer. containing 95 mole%, and Ri copolymer der molar ratio (a / b) is a 0.010 to 0.200 in (a) and (b), a kinematic viscosity at 100 ° C. of the lubricating oil composition 4.2~5.7mm a ² / s, the lubricating oil composition viscosity index is 398-800.
[In General Formula (1), R ¹ is a hydrogen atom or a methyl group; —X ¹ — is a group represented by —O— or —NH—, and R ² is a straight chain having 2 to 4 carbon atoms or It is a branched alkylene group, p is an integer of 0 to 20, R ² when p is 2 or more may be the same or different, and the (R ² O) _p portion may be a random bond or a block bond; R ³ is a branched alkyl group having 32 to 44 carbon atoms. ] The lubricating oil composition according to claim 1, wherein the ester oil base oil has a solubility parameter of 8.0 to 9.5 (cal/cm ³ ) ^1/2 . The lubricating oil composition according to claim 1, wherein the solubility parameter of (A) is 9.0 to 10.0 (cal/cm ³ ) ^1/2 . (A) is a monomer (c) represented by the following general formula (2) as a constituent monomer, and a (meth)acrylic acid linear alkyl ester (having a linear alkyl group having 12 to 36 carbon atoms ( The lubricating oil composition according to any one of claims 1 to 3, which is a copolymer containing at least one member selected from the group consisting of d).
[In General Formula (2), R ⁴ is a hydrogen atom or a methyl group; —X ² — is a group represented by —O— or —NH—, and R ⁵ is a straight chain having 2 to 4 carbon atoms or It is a branched alkylene group, q is an integer of 0 to 20, R ^{5 s} when q is 2 or more may be the same or different, and the (R ⁵ O) _q moiety may be a random bond or a block bond; R ⁶ is each independently a linear or branched alkyl group having 6 to 14 carbon atoms] The lubricating oil composition according to any one of claims 1 to 4, wherein the solubility parameter (A) has a dispersity of 0.10 to 1.00. (A) is 2 to 16 mol% of (a), 82 to 95 mol% of (b), and (c) and (d) based on the total number of moles of the monomers constituting (A). The lubricating oil composition according to claim 4, which is a copolymer containing 0.5 to 10 mol% in total. (A) is a nitrogen atom-containing monomer (excluding (a) and (c)) (e), a hydroxyl group-containing monomer (f) and a phosphorus atom-containing monomer (g) as constituent monomers. The lubricating oil composition according to any one of claims 1 to 6, which is a copolymer containing at least one selected from the group consisting of: The lubricating oil composition according to any one of claims 1 to 7, wherein the weight average molecular weight of (A) is 5,000 to 200,000. The lubricating oil composition according to any one of claims 1 to 8, which is a viscosity index improver composition further comprising a (co)polymer (B) having a macromonomer (r) as a constituent monomer. One or more additives selected from the group consisting of dispersants, detergents, antioxidants, oiliness improvers, pour point depressants, friction and wear modifiers, extreme pressure agents, defoamers, demulsifiers and corrosion inhibitors. the lubricating oil composition according to any one of comprising claim 1 to 9.