JP2019006845A - Rubber composition and tire using the same - Google Patents

Abstract

To provide a rubber composition which achieves both wet performance and snow performance at a high level, and a tire using the rubber composition.SOLUTION: The rubber composition contains a rubber component (A) and a petroleum-based hydrocarbon resin (B). The rubber component (A) contains 50 mass% or more of a modified natural rubber and 50 mass% or less of a styrene-butadiene rubber. The content of the petroleum-based hydrocarbon resin (B) is 5-50 pts.mass based on 100 pts.mass of the rubber component (A).SELECTED DRAWING: None

Description

  The present invention relates to a rubber composition and a tire using the rubber composition, and more particularly, to a rubber composition having both wet performance and snow performance highly compatible and a tire using the rubber composition.

  From the viewpoint of improving vehicle safety, various studies have been made to improve the braking performance and drive performance of tires on various road surfaces such as wet road surfaces, icy and snow road surfaces as well as dry road surfaces. For example, in order to improve the performance on a wet road surface, a technique is known in which a rubber composition containing an aroma oil and a rubber component such as natural rubber (NR) or butadiene rubber (BR) is used for tread rubber. Under such circumstances, Patent Document 1 discloses a rubber composition that can produce a tread rubber having high braking performance on a dry road surface and high braking performance on a wet road surface that is slippery as compared with asphalt, such as manholes. Has been proposed.

According to Patent Document 1, C ₅ resins, C ₅ -C ₉ resins, C ₉ resins, terpene resins, terpene - aromatics-based resin, rosin resin, dicyclopentadiene resins, and alkylphenol resins The blend of the thermoplastic resin selected more can increase the glass transition point (Tg) of the entire rubber composition, improve the loss tangent (tan δ) at 0 ° C., and improve the performance of the tire on the wet road surface. Further, the rubber component itself contains 70% by mass or more of natural rubber, so that it has high flexibility, and exhibits high braking performance even on a dry road surface or a wet road surface that is slippery such as a manhole.

International Publication No. 2015/0797703

  The rubber composition proposed in Patent Document 1 has a low exothermic property (low loss) by lowering tan δ by making a rubber composition flexible by compatibilizing a natural rubber phase with a petroleum hydrocarbon resin. Improves the wet performance of the resin. However, considering the safety of the vehicle, to improve wet performance such as braking performance and drivability on wet roads, steering stability, etc., and snow performance such as braking performance and drivability on icy and snowy road surfaces, steering stability. In addition, the present situation is that further improvement is required, and it is considered that there is still room for improvement.

  Accordingly, an object of the present invention is to provide a rubber composition having both wet performance and snow performance highly compatible with each other and a tire using the same.

  As a result of intensive studies to solve the above problems, the present inventor has found that the above problems can be solved by using a predetermined rubber component and a petroleum-based hydrocarbon resin at a predetermined ratio. It came to complete.

That is, the rubber composition for a tire of the present invention is a rubber composition containing a rubber component (A) and a petroleum hydrocarbon resin (B).
The rubber component (A) contains 50% by mass or more of modified natural rubber and 50% by mass or less of styrene-butadiene rubber, and the petroleum hydrocarbon resin (B) with respect to 100 parts by mass of the rubber component (A). ) Is 5 to 50 parts by mass.

In the rubber composition of the present invention, the modified natural rubber is preferably obtained by adding a polar group-containing hydrazide compound to natural rubber molecules in a natural rubber raw material. In the rubber composition of the present invention, the styrene-butadiene rubber is preferably modified with a hydrocarbyloxysilane compound. Further, in the rubber composition of the present invention, the petroleum hydrocarbon resin (B) is selected from the group consisting of C ₅ resins, C ₅ -C ₉ resins, C ₉ resins and dicyclopentadiene resins At least one kind is preferred.

  The tire of the present invention is obtained by using the rubber composition of the present invention as a tread rubber.

  ADVANTAGE OF THE INVENTION According to this invention, the rubber composition which made wet performance and snow performance compatible, and a tire using the same can be provided.

Hereinafter, the rubber composition of the present invention will be described in detail.
The rubber composition of the present invention is a rubber composition containing a rubber component (A) and a petroleum hydrocarbon resin (B). In the rubber composition of the present invention, the rubber component (A) contains 50% by mass or more of modified natural rubber (modified NR) and 50% by mass or less of styrene-butadiene rubber (SBR), and the rubber component (A). Petroleum-type hydrocarbon resin (B) is 5-50 mass parts with respect to 100 mass parts.

<Rubber component (A)>
The rubber component (A) used in the rubber composition of the present invention contains a modified NR of 50% by mass or more, preferably 60% by mass or more. By setting the content of the modified NR in the rubber component (A) to 50% by mass or more, the effect of the petroleum hydrocarbon resin (B) can be exhibited sufficiently. That is, the petroleum hydrocarbon resin (B) is easily compatible with the modified NR phase, the rubber becomes flexible, and the loss and wet performance and snow performance can be improved. Further, since the dispersibility of the filler can be increased, the storage elastic modulus E ′ at low temperature can be lowered, and tan δ from room temperature to high temperature range can be lowered, leading to reduction of rolling resistance. .

  The modified NR is obtained by graft-polymerizing a polar group-containing compound by applying mechanical shearing force to at least one natural rubber raw material selected from the group consisting of natural rubber, natural rubber latex coagulum, and natural rubber cup lamp. Things can be used. Since the polar group of the polar group-containing compound is excellent in affinity to various fillers such as carbon black and silica, the modified NR has a higher affinity for various fillers than the unmodified natural rubber. Therefore, the rubber composition using the modified NR as the rubber component has high dispersibility of the filler with respect to the rubber component, and the reinforcing effect of the filler is sufficiently exhibited. Exotherm is also greatly improved.

  When the polar group-containing compound is graft-polymerized to a natural rubber molecule in a natural rubber raw material, the polar group-containing compound preferably has a carbon-carbon double bond in the molecule, and is a polar group-containing vinyl monomer. It is preferable. Specific examples of polar groups of the polar group-containing vinyl monomer include amino groups, imino groups, nitrile groups, ammonium groups, imide groups, amide groups, hydrazo groups, hydrazide groups, azo groups, diazo groups, hydroxyl groups, Examples thereof include a carboxyl group, a carbonyl group, an epoxy group, an oxycarbonyl group, a nitrogen-containing heterocyclic group, an oxygen-containing heterocyclic group, a tin-containing group, and an alkoxysilyl group. These polar group-containing vinyl monomers may be used alone or in combination of two or more.

  In the rubber composition of the present invention, modified natural rubber is preferable because the effects of the present invention can be obtained satisfactorily. Examples of the vinyl monomer containing an epoxy group include (meth) allyl glycidyl ether, glycidyl (meth) acrylate, and 3,4-oxycyclohexyl (meth) acrylate. These epoxy group-containing vinyl monomers may be used alone or in combination of two or more.

  As the natural rubber raw material, various solid natural rubbers after drying, various natural rubber latex coagulated products (including unsmoked sheets) or natural rubber cup lamps can be used, and these natural rubber raw materials are used alone. Or may be used in combination of two or more.

  The rubber composition of the present invention contains SBR in an amount of 50% by mass or less, preferably 20 to 40% by mass of the rubber component (A). In the rubber composition of the present invention, modified SBR can be used as SBR, and the modified SBR is preferably hydrocarbyloxysilane compound-modified. When silica is added as a filler to the rubber composition of the present invention, silica is unevenly distributed in the modified SBR, so that strength can be obtained without deteriorating tan δ.

  There is no restriction | limiting in particular as a modified functional group in modified | denatured SBR, According to the objective, it can select suitably. As the modified functional group, for example, a modified functional group having an interaction property with respect to the filler is preferably exemplified. The interaction with the filler can be enhanced, and both low loss and wear resistance can be achieved at a higher level. Here, the “modified functional group having an interaction property with the filler” means, for example, a covalent bond between the modified functional group and the surface of the filler (for example, silica); intermolecular force (ion-dipolar) It means a functional group capable of forming a dipole interaction), a dipole-dipole interaction, an intermolecular force such as a hydrogen bond or van der Waals force. There is no restriction | limiting in particular as a modified functional group with high interaction property with a filler (for example, silica), For example, a nitrogen-containing functional group, a silicon-containing functional group, an oxygen-containing functional group etc. are mentioned suitably.

  The polymerization method for obtaining the modified SBR is not particularly limited, and a known method can be used. Examples of such polymerization methods include anionic polymerization, coordination polymerization, and emulsion polymerization. The modifier for obtaining the modified SBR can be appropriately selected from known modifiers. The modifier may be, for example, a modifier that reacts with a polymerization active terminal of anionic polymerization or coordination polymerization, or an amide portion of a lithium amide compound used as a polymerization initiator.

  As the modifier for obtaining the modified SBR, it can be appropriately selected from the above-mentioned known modifiers having a modified functional group. The modifier is preferably a modifier having at least one atom selected from a silicon atom, a nitrogen atom and an oxygen atom. In order to have high interaction property with the filler (for example, silica), the modifier is preferably at least one selected from the group consisting of alkoxysilane compounds, hydrocarbyloxysilane compounds, and combinations thereof.

一般式（Ｉ）中、Ｒ^１およびＲ^２は、それぞれ独立に炭素原子数１〜２０の一価の脂肪族炭化水素基または炭素原子数６〜１８の一価の芳香族炭化水素基を示し、ａは０〜２の整数であり、ＯＲ^２が複数ある場合、各ＯＲ^２は互いに同一でも異なっていてもよく、また分子中には活性プロトンは含まれない。 The alkoxysilane compound is not particularly limited, but is more preferably an alkoxysilane compound represented by the following general formula (I).

In general formula (I), R ¹ and R ² each independently represent a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms. , A is an integer of 0 to 2, and when there are a plurality of OR ² , each OR ² may be the same as or different from each other, and no active proton is contained in the molecule.

  Specific examples of the alkoxysilane compound represented by the general formula (I) include N- (1,3-dimethylbutylidene) -3-triethoxysilyl-1-propanamine, tetramethoxysilane, tetraethoxysilane, tetra -N-propoxysilane, tetraisopropoxysilane, tetra-n-butoxysilane, tetraisobutoxysilane, tetra-sec-butoxysilane, tetra-tert-butoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxy Silane, methyltriisopropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltripropoxysilane, ethyltriisopropoxysilane, propyltrimethoxysilane, propyltriethoxysilane, propyltripropoxy Orchid, propyltriisopropoxysilane, butyltrimethoxysilane, butyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethyltrimethoxysilane, methylphenyldimethoxysilane, dimethyldiethoxysilane, vinyltrimethoxysilane, vinyltri Examples include ethoxysilane, divinyldiethoxysilane, 3-bis (trimethylsilyl) aminopropyl-methyldiethoxysilane. Among these, N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine, tetraethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, 3-bis (trimethylsilyl) amino Propyl-methyldiethoxysilane is preferred. An alkoxysilane compound may be used individually by 1 type, and may be used in combination of 2 or more type.

  The hydrocarbyloxysilane compound is preferably a hydrocarbyloxysilane compound represented by the following general formula (II).

一般式（ＩＩ）中、ｎ１＋ｎ２＋ｎ３＋ｎ４＝４（ただし、ｎ２は１〜４の整数であり、ｎ１、ｎ３およびｎ４は０〜３の整数である）であり、Ａ^１は、飽和環状３級アミン化合物残基、不飽和環状３級アミン化合物残基、ケチミン残基、ニトリル基、（チオ）イソシアナート基、（チオ）エポキシ基、イソシアヌル酸トリヒドロカルビルエステル基、炭酸ジヒドロカルビルエステル基、ニトリル基、ビリジン基、（チオ）ケトン基、（チオ）アルデヒド基、アミド基、（チオ）カルボン酸エステル基、（チオ）カルボン酸エステルの金属塩、カルボン酸無水物残基、カルボン酸ハロゲン化合物残基、並びに加水分解性基を有する第一もしくは第二アミノ基またはメルカプト基の中から選択される少なくとも１種の官能基であり、ｎ４が２以上の場合には同一でも異なっていてもよく、Ａ^１は、Ｓｉと結合して環状構造を形成する二価の基であってもよく、Ｒ^２１は、炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の一価の芳香族炭化水素基であり、ｎ１が２以上の場合には同一でも異なっていてもよく、Ｒ^２３は、炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基、炭素原子数６〜１８の一価の芳香族炭化水素基またはハロゲン原子であり、ｎ３が２以上の場合には同一でも異なっていてもよく、Ｒ^２２は、炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の一価の芳香族炭化水素基であり、いずれも窒素原子および／またはケイ素原子を含有していてもよく、ｎ２が２以上の場合には、互いに同一もしくは異なっていてもよく、あるいは、一緒になって環を形成しており、Ｒ^２４は、炭素原子数１〜２０の二価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の二価の芳香族炭化水素基であり、ｎ４が２以上の場合には同一でも異なっていてもよい。

In general formula (II), n1 + n2 + n3 + n4 = 4 (where n2 is an integer of 1 to 4, and n1, n3 and n4 are integers of 0 to 3), and A ¹ is a saturated cyclic tertiary amine compound Residue, unsaturated cyclic tertiary amine compound residue, ketimine residue, nitrile group, (thio) isocyanate group, (thio) epoxy group, isocyanuric acid trihydrocarbyl ester group, carbonic acid dihydrocarbyl ester group, nitrile group, pyridine Group, (thio) ketone group, (thio) aldehyde group, amide group, (thio) carboxylic acid ester group, metal salt of (thio) carboxylic acid ester, carboxylic acid anhydride residue, carboxylic acid halogen compound residue, and It is at least one functional group selected from a primary or secondary amino group having a hydrolyzable group or a mercapto group, and n4 is 2 or more. In the above case, they may be the same or different, A ¹ may be a divalent group that forms a cyclic structure by bonding to Si, and R ²¹ is a monovalent group having 1 to 20 carbon atoms. of an aliphatic or alicyclic hydrocarbon group or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, may be the same or different when n1 is 2 or more, R ²³ is a carbon A monovalent aliphatic or alicyclic hydrocarbon group having 1 to 20 atoms, a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, or a halogen atom, the same when n3 is 2 or more R ²² is a monovalent aliphatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, When nitrogen atom and / or silicon atom may be contained and n2 is 2 or more May be the same or different from each other, or together form a ring, and R ²⁴ is a divalent aliphatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms or a carbon atom. A divalent aromatic hydrocarbon group having 6 to 18 atoms, and when n4 is 2 or more, they may be the same or different.

  The hydrolyzable group in the first or second amino group having a hydrolyzable group or the mercapto group having a hydrolyzable group is preferably a trimethylsilyl group or a tert-butyldimethylsilyl group, particularly preferably a trimethylsilyl group.

  The hydrocarbyloxysilane compound represented by the general formula (II) is preferably a hydrocarbyloxysilane compound represented by the following general formula (III).

一般式（ＩＩＩ）中、ｐ１＋ｐ２＋ｐ３＝２（ただし、ｐ２は１〜２の整数であり、ｐ１およびｐ３は０〜１の整数である）であり、Ａ^２は、ＮＲａ（Ｒａは、一価の炭化水素基、加水分解性基または含窒素有機基である）、あるいは、硫黄であり、Ｒ^２５は、炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の一価の芳香族炭化水素基であり、Ｒ^２７は、炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基、炭素原子数６〜１８の一価の芳香族炭化水素基またはハロゲン原子であり、Ｒ^２６は、炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基、炭素原子数６〜１８の一価の芳香族炭化水素基または含窒素有機基であり、いずれも窒素原子および／またはケイ素原子を含有していてもよく、ｐ２が２の場合には、互いに同一でも異なっていてもよく、あるいは、一緒になって環を形成しており、Ｒ^２８は、炭素原子数１〜２０の二価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の二価の芳香族炭化水素基である。加水分解性基として、トリメチルシリル基またはｔｅｒｔ−ブチルジメチルシリル塞が好ましく、トリメチルシリル塞が特に好ましい。

In general formula (III), p1 + p2 + p3 = 2 (wherein p2 is an integer of 1 to 2 and p1 and p3 are integers of 0 to 1), A ² is NRa (Ra is a monovalent) A hydrocarbon group, a hydrolyzable group or a nitrogen-containing organic group), or sulfur, and R ²⁵ is a monovalent aliphatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms or the number of carbon atoms. A monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, wherein R ²⁷ is a monovalent aliphatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms, and a monovalent aromatic group having 6 to 18 carbon atoms. An aromatic hydrocarbon group or a halogen atom, and R ²⁶ represents a monovalent aliphatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms, a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, or Nitrogen-containing organic groups, both containing nitrogen and / or silicon atoms And when p2 is 2, they may be the same or different from each other, or together form a ring, and R ²⁸ is a divalent group having 1 to 20 carbon atoms. An aliphatic or alicyclic hydrocarbon group or a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms. As the hydrolyzable group, a trimethylsilyl group or a tert-butyldimethylsilyl block is preferable, and a trimethylsilyl block is particularly preferable.

  The hydrocarbyloxysilane compound represented by the general formula (II) is preferably a hydrocarbyloxysilane compound represented by the following general formula (IV) or (V).

一般式（ＩＶ）中、ｑ１＋ｑ２＝３（ただし、ｑ１は０〜２の整数であり、ｑ２は１〜３の整数である）であり、Ｒ^３１は炭素原子数１〜２０の二価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の二価の芳香族炭化水素基であり、Ｒ^３２およびＲ^３３はそれぞれ独立して加水分解性基、炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の一価の芳香族炭化水素基であり、Ｒ^３４は炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の一価の芳香族炭化水素基であり、ｑ１が２の場合には同一でも異なっていてもよく、Ｒ^３５は炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の一価の芳香族炭化水素基であり、ｑ２が２以上の場合には同一でも異なっていてもよい。

In general formula (IV), q1 + q2 = 3 (where q1 is an integer of 0 to 2 and q2 is an integer of 1 to 3), and R ³¹ is a divalent fat having 1 to 20 carbon atoms. An aliphatic or alicyclic hydrocarbon group or a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms, wherein R ³² and R ³³ are each independently a hydrolyzable group having 1 to 20 carbon atoms. A monovalent aliphatic or alicyclic hydrocarbon group or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, and R ³⁴ is a monovalent aliphatic or alicyclic carbon group having 1 to 20 carbon atoms. A hydrogen group or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms and may be the same or different when q1 is 2, and R ³⁵ is a monovalent fatty acid having 1 to 20 carbon atoms Or alicyclic hydrocarbon group or monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms There, in the case of q2 is 2 or more may be the same or different.

一般式（Ｖ）中、ｒ１＋ｒ２＝３（ただし、ｒ１は１〜３の整数であり、ｒ２は０〜２の整数である）であり、Ｒ^３６は炭素原子数１〜２０の二価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の二価の芳香族炭化水素基であり、Ｒ^３７はジメチルアミノメチル基、ジメチルアミノエチル基、ジエチルアミノメチル基、ジエチルアミノエチル基、メチルシリル（メチル）アミノメチル基、メチルシリル（メチル）アミノエチル基、メチルシリル（エチル）アミノメチル基、メチルシリル（エチル）アミノエチル基、ジメチルシリルアミノメチル基、ジメチルシリルアミノエチル基、炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の一価の芳香族炭化水素基であり、ｒ１が２以上の場合には同一でも異なっていてもよく、Ｒ^３８は炭素原子数１〜２０のヒドロカルビルオキシ基、炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の一価の芳香族炭化水素基であり、ｒ２が２の場合には同一でも異なっていてもよい。

In the general formula (V), r1 + r2 = 3 ( however, r1 is an integer of 1 to 3, r2 is 0 to 2 is an integer) of ^{a, R 36} is an aliphatic divalent from 1 to 20 carbon atoms R ³⁷ is a dimethylaminomethyl group, a dimethylaminoethyl group, a diethylaminomethyl group, a diethylaminoethyl group, a methylsilyl ( Methyl) aminomethyl group, methylsilyl (methyl) aminoethyl group, methylsilyl (ethyl) aminomethyl group, methylsilyl (ethyl) aminoethyl group, dimethylsilylaminomethyl group, dimethylsilylaminoethyl group, 1 to 20 carbon atoms A valent aliphatic or alicyclic hydrocarbon group or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, wherein r1 is 2 or more May be the same or different in, R ³⁸ is 6-18 hydrocarbyloxy group, the number aliphatic or alicyclic hydrocarbon group or a carbon atom monovalent having 1 to 20 carbon atoms having 1 to 20 carbon atoms Monovalent aromatic hydrocarbon group, and when r2 is 2, they may be the same or different.

  The hydrocarbyloxysilane compound represented by the general formula (II) is preferably a hydrocarbyloxysilane compound having two or more nitrogen atoms represented by the following general formula (VI) or (VII). Thereby, both low loss and wear resistance can be achieved at a higher level.

一般式（ＶＩ）中、Ｒ^４０はトリメチルシリル基、炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の一価の芳香族炭化水素基であり、Ｒ^４１は炭素原子数１〜２０のヒドロカルビルオキシ基、炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の一価の芳香族炭化水素基であり、Ｒ^４２は炭素原子数１〜２０の二価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の二価の芳香族炭化水素基である。

In the general formula (VI), R ⁴⁰ is a trimethylsilyl group, a monovalent aliphatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms, or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms. , R ⁴¹ is a hydrocarbyloxy group having 1 to 20 carbon atoms, a monovalent aliphatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms, or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms. And R ⁴² is a divalent aliphatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms or a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms.

一般式（ＶＩＩ）中、Ｒ^４３およびＲ^４４はそれぞれ独立して炭素原子数１〜２０の二価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の二価の芳香族炭化水素基であり、Ｒ^４５は炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の一価の芳香族炭化水素基であり、各Ｒ^４５は、同一でも異なっていてもよい。

In the general formula (VII), R ⁴³ and R ⁴⁴ are each independently a divalent aliphatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms or a divalent aromatic carbon group having 6 to 18 carbon atoms. R ⁴⁵ is a monovalent aliphatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, and each R ⁴⁵ is May be the same or different.

  The hydrocarbyloxysilane compound represented by the general formula (II) is preferably a hydrocarbyloxysilane compound represented by the following general formula (VIII).

一般式（ＶＩＩＩ）中、ｒ１＋ｒ２＝３（ただし、ｒ１は０〜２の整数であり、ｒ２は１〜３の整数である）であり、Ｒ^４６は炭素原子数１〜２０の二価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の二価の芳香族炭化水素基であり、Ｒ^４７およびＲ^４８はそれぞれ独立して炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の一価の芳香族炭化水素基である。複数のＲ^４７またはＲ^４８は、同一でも異なっていてもよい。

In general formula (VIII), r1 + r2 = 3 (wherein r1 is an integer of 0 to 2 and r2 is an integer of 1 to 3), and R ⁴⁶ is a divalent fat having 1 to 20 carbon atoms. An aliphatic or alicyclic hydrocarbon group or a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms, wherein R ⁴⁷ and R ⁴⁸ are each independently a monovalent aliphatic group having 1 to 20 carbon atoms or An alicyclic hydrocarbon group or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms. A plurality of R ⁴⁷ or R ⁴⁸ may be the same or different.

  The hydrocarbyloxysilane compound represented by the general formula (II) is preferably a hydrocarbyloxysilane compound represented by the following general formula (IX).

一般式（ＩＸ）中、Ｘはハロゲン原子であり、Ｒ^４９は炭素原子数１〜２０の二価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の二価の芳香族炭化水素基であり、Ｒ^５０およびＲ^５１はそれぞれ独立して加水分解性基、炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の一価の芳香族炭化水素基であるか、あるいは、Ｒ^５０およびＲ^５１は結合して二価の有機基を形成しており、Ｒ^５２およびＲ^５３はそれぞれ独立してハロゲン原子、ヒドロカルビルオキシ基、炭素原子数１〜２０の一価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の一価の芳香族炭化水素基である。Ｒ^５０およびＲ^５１としては、加水分解性基であることが好ましく、加水分解性基として、トリメチルシリル基またはｔｅｒｔ−ブチルジメチルシリル基が好ましく、トリメチルシリル基が特に好ましい。

In the general formula (IX), X is a halogen atom, and R ⁴⁹ is a divalent aliphatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms or a divalent aromatic carbon group having 6 to 18 carbon atoms. R ⁵⁰ and R ⁵¹ are each independently a hydrolyzable group, a monovalent aliphatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms, or a monovalent group having 6 to 18 carbon atoms. R ⁵⁰ and R ⁵¹ are bonded to form a divalent organic group, and R ⁵² and R ⁵³ are each independently a halogen atom, a hydrocarbyloxy group, or a carbon atom. A monovalent aliphatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms. R ⁵⁰ and R ⁵¹ are preferably hydrolyzable groups, and the hydrolyzable group is preferably a trimethylsilyl group or a tert-butyldimethylsilyl group, and particularly preferably a trimethylsilyl group.

  The hydrocarbyloxysilane compound represented by the general formula (II) is preferably a hydrocarbyloxysilane compound having a structure represented by the following general formulas (X) to (XIII).

一般式（Ｘ）〜（ＸＩＩＩ）中、記号Ｕ、Ｖはそれぞれ０〜２かつＵ＋Ｖ＝２を満たす整数である。一般式（Ｘ）〜（ＸＩＩＩ）中のＲ^５４〜^９２は同一でも異なっていてもよく、炭素原子数１〜２０の二価の脂肪族もしくは脂環式炭化水素基または炭素原子数６〜１８の二価の芳香族炭化水素基である。一般式（ＸＩＩＩ）中のαおよびβは０〜５の整数である。

In the general formulas (X) to (XIII), symbols U and V are integers satisfying 0 to 2 and U + V = 2, respectively. R ⁵⁴ to ⁹² in the general formulas (X) to (XIII) may be the same or different, and are a divalent aliphatic or alicyclic hydrocarbon group having 1 to 20 carbon atoms, or 6 to 18 carbon atoms. These are divalent aromatic hydrocarbon groups. Α and β in the general formula (XIII) are integers of 0 to 5.

  Among the compounds of the general formulas (X) to (XII), N1, N1, N7-tetramethyl-4-((trimethoxysilyl) methyl) -1,7-heptane, 2-((hexylodimethoxysilyl) methyl ) -N1, N1, N3, N3-2-pentamethylpropane-1,3-diamine, N1- (3- (dimethylamino) propyl-N3, N3-dimethyl-N1- (3- (trimethoxysilyl) propyl ) Propane-1,3-diamine, 4- (3- (dimethylamino) propyl) -N1, N1, N7, N7-tetramethyl-4-((trimethoxysilyl) methyl) heptane-1,7-diamine preferable.

  Among the compounds of the general formula (XIII), N, N-dimethyl-2- (3- (dimethoxymethylsilyl) propoxy) ethanamine, N, N-bis (trimethylsilyl) -2- (3- (trimethoxysilyl) propoxy ) Ethanamine, N, N-dimethyl-2- (3- (trimethoxysilyl) propoxy) ethanamine, N, N-dimethyl-3- (3- (trimethoxysilyl) propoxy) propan-1-amine are preferred.

  The hydrocarbyloxysilane compounds represented by the general formulas (II) to (XIII) are preferably alkoxysilane compounds.

  Suitable modifiers for obtaining a modified polymer as a modified SBR by anionic polymerization include, for example, 3,4-bis (trimethylsilyloxy) -1-vinylbenzene, 3,4-bis (trimethylsilyloxy) benzaldehyde, 3 , 4-bis (tert-butyldimethylsilyloxy) benzaldehyde, 2-cyanopyridine, 1,3-dimethyl-2-imidazolidinone, and 1-methyl-2-pyrrolidone.

  The modifying agent is preferably an amide portion of a lithium amide compound used as a polymerization initiator in anionic polymerization. Examples of such lithium amide compounds include lithium hexamethylene imide, lithium pyrrolidide, lithium piperidide, lithium heptamethylene imide, lithium dodecamethylene imide, lithium dimethyl amide, lithium diethyl amide, lithium dibutyl amide, and lithium dipropyl amide. , Lithium diheptylamide, lithium dihexylamide, lithium dioctylamide, lithium di-2-ethylhexylamide, lithium didecylamide, lithium-N-methylpiperazide, lithium ethylpropylamide, lithium ethylbutyramide, lithium ethylbenzylamide, lithium methylphenethyl Examples include amides and combinations thereof. For example, the modifying agent that becomes the amide portion of lithium hexamethyleneimide is hexamethyleneimine, the modifying agent that becomes the amide portion of lithium pyrrolidide is pyrrolidine, and the modifying agent that becomes the amide portion of lithium piperidide is piperidine. .

  Suitable modifiers for obtaining a modified polymer as a modified SBR by coordination polymerization include, for example, at least one compound selected from 2-cyanopyridine and 3,4-ditrimethylsilyloxybenzaldehyde.

  Suitable modifiers for obtaining a modified polymer as a modified SBR by emulsion polymerization include, for example, at least one compound selected from 3,4-ditrimethylsilyloxybenzaldehyde and 4-hexamethyleneiminoalkylstyrene. . These modifiers preferably used in emulsion polymerization are preferably copolymerized at the time of emulsion polymerization as monomers containing nitrogen atoms and / or silicon atoms.

  There is no restriction | limiting in particular as a modified | denatured rate in modified | denatured SBR, According to the objective, it can select suitably. For example, the modification rate is preferably 30% or more, more preferably 35% or more, and particularly preferably 70% or more.

  The rubber composition of the present invention may contain other rubber components as long as the effects of the present invention are not impaired. Examples of other rubber components include natural rubber, unmodified conjugated diene-aromatic vinyl copolymer, such as emulsion-polymerized styrene-butadiene rubber, unmodified solution-polymerized styrene-butadiene rubber, polybutadiene rubber, and polyisoprene rubber. Styrene-isoprene rubber, ethylene-α-olefin copolymer rubber, ethylene-α-olefin-diene copolymer rubber, chloroprene rubber, halogenated butyl rubber, and copolymer of styrene and isobutylene having a halogenated methyl group. Can be mentioned.

<Petroleum hydrocarbon resin (B)>
The rubber composition of the present invention comprises 5 to 50 parts by mass, preferably 10 to 30 parts by mass of the petroleum hydrocarbon resin (B). Preferably, petroleum hydrocarbon resin (B) Examples of the C ₅ resins, C ₅ -C ₉ resins, at least one member selected from the group consisting of C ₉ resins and dicyclopentadiene resins, rubber component 100 parts by weight 5 to 50 parts by mass, preferably 10 to 30 parts by mass based on the amount. By satisfying such a range, the rubber composition of the present invention has a high glass transition point (Tg) and an improved loss tangent (tan δ) at 0 ° C. Therefore, the performance of the tire mainly on a wet road surface is improved. Can be improved. The rubber component (A) in the rubber composition of the present invention contains 50% by mass or more of the modified NR, but the petroleum hydrocarbon resin (B) is highly compatible with the modified NR. This effect is particularly easy to obtain.

In the present invention, “C ₅ resin” refers to a C ₅ synthetic petroleum resin, for example, a solid polymer obtained by polymerizing a C ₅ fraction using a Friedel-Crafts type catalyst such as AlCl ₃ or BF _3. Point to. Specifically, a copolymer mainly composed of isoprene, cyclopentadiene, 1,3-pentadiene and 1-pentene, a copolymer of 2-pentene and dicyclopentadiene, and mainly 1,3-pentadiene. And the like. In addition, if C5 type resin is used as petroleum type hydrocarbon resin (B), the braking performance on an icy and snowy road surface can also be improved.

In the present invention, the “C ₅ -C ₉ series resin” refers to a C ₅ -C ₉ series synthetic petroleum resin, for example, using a Friedel-Crafts type catalyst such as AlCl ₃ or BF ₃ , and C ₅ -C ₁₁ A solid polymer obtained by polymerizing a component. Examples of the “C ₅ -C ₉ resin” include copolymers having styrene, vinyl toluene, α-methyl styrene, indene and the like as main components. In the present invention, as the C _{5 to} C ₉ resin, a resin having a small component of C ₉ or more is preferable from the viewpoint of compatibility with the rubber component (A). Here, “there is little component of C ₉ or more” means that the component of C ₉ or more in the total amount of the resin is less than 50% by mass, preferably 40% by mass or less. Note that the use of the C ₅ -C ₉ resins as petroleum hydrocarbon resin (B), it is also possible to further improve the handling properties. The C _{5 to} C ₁₁ fraction used for the polymerization of the solid polymer as “C _{5 to} C ₉ resin” includes fractions other than the C ₅ fraction and the C ₉ fraction. .

The "C ₉ resin" in the present invention refers to C ₉ based synthetic petroleum resins, for example, using a Friedel-Crafts catalyst such as AlCl ₃ or BF _3, the solid weight obtained by polymerizing a C ₉ fraction Refers to coalescence. As the "C ₉ resins", for example, indene, alpha-methyl styrene, copolymers thereof as a main component a vinyl toluene. Note that the use of the C ₉ resins as petroleum hydrocarbon resin (B), it is also possible to further improve the handling performance.

The dicyclopentadiene resin refers to a resin obtained by polymerizing dicyclopentadiene using a Friedel-Crafts type catalyst such as AlCl ₃ or BF ₃ . Specific examples of commercially available dicyclopentadiene resins include Quinton 1920 (manufactured by Nippon Zeon), Quinton 1105 (manufactured by Nippon Zeon), Marcaretz M-890A (manufactured by Maruzen Petrochemical), and the like. In addition, if dicyclopentadiene resin is used as a petroleum-type hydrocarbon resin (B), the braking performance on an icy and snowy road surface can also be improved.

  The petroleum hydrocarbon resin (B) is blended in an amount of 5 to 50 parts by weight, preferably 10 to 30 parts by weight, per 100 parts by weight of the rubber component (A). Desired wet performance and snow performance can be ensured by setting the blending amount of the petroleum hydrocarbon resin (B) to 5 to 50 parts by mass with respect to 100 parts by mass of the rubber component (A). When the blending amount of the petroleum hydrocarbon resin (B) is less than 5 parts by mass, the braking performance on the wet road surface is not sufficiently exhibited, while when it exceeds 50 parts by mass, desired wet performance and snow performance are achieved. May be difficult to obtain.

<Filler>
The rubber composition of the present invention may contain a filler. In this case, a filler is 20-120 mass parts with respect to 100 mass parts of rubber components (A), Preferably it is 50-100 mass parts. Further, the filler contains 50 to 100% by mass of silica, preferably 80 to 100% by mass, and more preferably 90 to 100% by mass. That is, the rubber composition of the present invention preferably contains 10 to 120 parts by mass of silica, more preferably 45 to 100 parts by mass with respect to 100 parts by mass of the rubber component (A). By setting the blending amount of the filler to 20 to 120 parts by mass with respect to 100 parts by mass of the rubber component (A), the reinforcing effect can be exhibited without impairing the properties such as flexibility of the rubber component (A). it can. Furthermore, the blending amount of silica in the filler is 50 to 100% by mass, and in particular, the effects of reducing rolling resistance and improving braking performance on wet road surfaces are achieved, and the flexibility of the rubber component is increased. The advantage that it is hard to damage is obtained.

  The effect of silica blending in the rubber composition of the present invention is that the modified NR and the petroleum-based hydrocarbon resin (B) are well dispersed and have sufficient reinforcement and low heat build-up without losing its flexibility. Can be given. Therefore, the rubber composition of the present invention has high followability to a road surface with a low coefficient of friction (for example, a slippery wet road surface such as a manhole) due to its flexibility, and sufficient braking performance on such a slippery wet road surface. Can be played.

Examples of silica include wet silica (hydrous silicic acid), dry silica (anhydrous silicic acid), calcium silicate, aluminum silicate, and the like. Among these, wet silica can be preferably used. Is preferably a BET specific surface area of the wet silica is 40~350m ² / g, more preferably from 150 to 300 m ² / g, and even more preferably 200~250m ² / g. Silica having a BET specific surface area within this range has an advantage that both rubber reinforcement and dispersibility in a rubber component can be achieved. From this viewpoint, silica having a BET specific surface area in the range of 80 to 300 m ² / g is more preferable. Commercially available products such as Tosoh Silica Co., Ltd., trade names “Nipsil AQ”, “Nipsil KQ”, Evonik, trade name “Ultrasil VN3”, etc. can be used as such silica. This silica may be used individually by 1 type, and may be used in combination of 2 or more type.

  As a filler, in addition to silica, carbon black, aluminum oxide, clay, alumina, talc, mica, kaolin, glass balloon, glass beads, calcium carbonate, magnesium carbonate, magnesium hydroxide, calcium carbonate, magnesium oxide, titanium oxide , Potassium titanate, barium sulfate and the like can be appropriately blended.

<Softener>
A softener may be further blended in the rubber composition of the present invention. Here, examples of the softener include petroleum softeners such as aroma oil, paraffin oil, and naphthene oil, and plant softeners such as palm oil, castor oil, cottonseed oil, and soybean oil. When blending a softener, from the viewpoint of ease of handling, the softener is a liquid that is liquid at room temperature such as 25 ° C., such as petroleum oils such as aroma oil, paraffin oil, naphthenic oil, etc. It is preferable to add a softener and not to add a plant softener. And when mix | blending a softener, it is preferable that a rubber composition mix | blends a softener with 10 mass parts or less with respect to 100 mass parts of rubber components (A), and is 5 mass parts or less. It is more preferable to blend. When the blending amount of the softening agent is 10 parts by mass or less with respect to 100 parts by mass of the rubber component (A), the effect of improving the braking performance on a wet road surface that is slippery as compared with asphalt, such as manholes, can be enhanced. . However, from the viewpoint of braking performance on wet road surfaces, it is particularly preferable not to add a softener to the rubber composition of the present invention.

<Silane coupling agent>
In the rubber composition of the present invention, a silane coupling agent may be blended for the purpose of further improving the reinforcing property and low heat build-up property of the blended silica. Examples of silane coupling agents include bis (3-triethoxysilylpropyl) tetrasulfide, bis (3-triethoxysilylpropyl) trisulfide, bis (3-triethoxysilylpropyl) disulfide, and bis (2-triethoxysilyl). Ethyl) tetrasulfide, bis (3-trimethoxysilylpropyl) tetrasulfide, bis (2-trimethoxysilylethyl) tetrasulfide, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltri Methoxysilane, 2-mercaptoethyltriethoxysilane, 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-triethoxysilylpropyl-N, N-dimethylthiocarba Yl tetrasulfide, 2-triethoxysilylethyl-N, N-dimethylthiocarbamoyl tetrasulfide, 3-trimethoxysilylpropylbenzothiazolyl tetrasulfide, 3-triethoxysilylpropylbenzoyl tetrasulfide, 3-triethoxysilyl Propyl methacrylate monosulfide, 3-trimethoxysilylpropyl methacrylate monosulfide, bis (3-diethoxymethylsilylpropyl) tetrasulfide, 3-mercaptopropyldimethoxymethylsilane, dimethoxymethylsilylpropyl-N, N-dimethylthiocarbamoyl tetrasulfide , Dimethoxymethylsilylpropylbenzothiazolyl tetrasulfide, and the like. Among these, bis (3-tri- Butoxy silyl propyl) polysulfide and 3-trimethoxysilylpropyl benzothiazyl tetrasulfide are preferable. One of these silane coupling agents may be used alone, or two or more thereof may be used in combination.

  In the rubber composition of the present invention, a preferable blending amount of the silane coupling agent varies depending on the kind of the silane coupling agent and the like, but is preferably selected in a range of 2 to 25% by mass with respect to silica. If this amount is less than 2% by mass, the effect as a coupling agent is hardly exhibited, and if it exceeds 25% by mass, the rubber component may be gelled. From the viewpoints of the effect as a coupling agent and prevention of gelation, the more preferred blending amount of this silane coupling agent is in the range of 2 to 20% by weight, and the more preferred blending amount is in the range of 5 to 18% by weight. The particularly preferred blending amount is in the range of 5 to 15% by mass.

<Others>
The rubber composition of the present invention further contains a compounding agent usually used in the rubber industry, such as an anti-aging agent, a vulcanization accelerator, a vulcanization acceleration aid, a vulcanizing agent, and the like. It can select suitably in the range which does not carry out, and can mix | blend within the range of a normal compounding quantity. As these compounding agents, commercially available products can be suitably used. The rubber composition of the present invention is kneaded by blending the rubber component (A) with the petroleum hydrocarbon resin (B) and a filler, softener and various compounding agents appropriately selected as necessary. , Heating, extruding and the like.

  The tire of the present invention is characterized by using the above-described rubber composition for a tread rubber. The tire of the present invention can be produced by forming a raw tire using the above rubber composition as a tread rubber and vulcanizing the raw tire according to a conventional method. In addition, since the above-mentioned rubber composition is used for the tread rubber of the tire of the present invention, the tire of the present invention has particularly good performance on both ice and snow road surfaces and wet road surfaces. Moreover, as gas with which the tire of the present invention is filled, an inert gas such as nitrogen, argon, helium, etc. can be used in addition to normal or air having an adjusted oxygen partial pressure.

Hereinafter, the present invention will be described in more detail with reference to examples.
<Examples 1 to 5 and Comparative Examples 1 and 2>
A rubber composition having the composition shown in Table 1 was prepared. Using the obtained rubber composition as a tread rubber, a passenger car radial tire having a size of 185 / 70R13 was produced according to a conventional method. The rolling resistance, wet performance and snow performance of each produced tire were evaluated by the following procedure. The obtained results are also shown in Table 1. In addition, the unit of the compounding quantity in a table | surface is a mass part. Modified NR1, modified NR2, modified NR3, modified NR4 and modified SBR were synthesized by the following procedure.

Synthesis of Modified NR1 The pH was adjusted to 4.7 by adding formic acid to the field latex and coagulated. This solid was treated 5 times with a creper and crushed through a shredder. After determining the dry rubber content of this coagulated product, 600 g of the coagulated product and an emulsion solution of 3.0 g of isonicotinohydrazide in terms of dry rubber were kneaded for 2 minutes at 30 rpm in a kneader (prebreaker) at room temperature. The resulting modified NR1 was dried and uniformly dispersed and dried. Further, this unmodified NR1 was extracted with petroleum ether, and further extracted with a 2: 1 mixed solvent of acetone and methanol to separate the unreacted hydrazide compound. From the analysis of the extract, the unreacted hydrazide compound was analyzed. Thus, the addition amount of isonicotinohydrazide in the modified NR1 was 0.5% by mass with respect to the solid rubber component in the natural rubber raw material.

Synthesis of modified NR2 In place of 3.0 g of isonicotinohydrazide in the modified NR1 synthesis example, 3.0 g of 3- (dimethylamino) propane hydrazide was added, and otherwise modified NR2 was obtained in the same manner as in the modified NR1 synthesis example. It was.

Synthesis of modified NR3 Instead of using a coagulum obtained by adding formic acid to a field latex in the modified NR1 synthesis example, a modified NR3 synthesis is obtained by natural coagulation of a latex obtained from a natural rubber tree. The modified NR3 was obtained in the same manner as in the modified NR1 synthesis example except that

Synthesis of Modified NR4 In place of 3.0 g of isonicotinohydrazide in the modified NR3 synthesis example, 8.5 g of 4- (tributyltin) butanehydrazide was added, and a modified NR4 was obtained in the same manner as in the modified NR3 synthesis example. .

Synthesis of modified SBR Add 1,3-butadiene in cyclohexane and styrene in cyclohexane to 800 mL pressure-resistant glass container that has been dried and purged with nitrogen so that 1,3-butadiene 67.59 and styrene 7.59. Then, 0.6 mmol of 2,2-ditetrahydrofurylpropane was added and 0.8 mmol of n-butyllithium was added, followed by polymerization at 50 ° C. for 1.5 hours. In this case, N, N-bis (trimethylsilyl) -3- [diethoxy (methyl) silyl] propylamine (general formula (IV)) is used as a modifier for the polymerization reaction system in which the polymerization conversion rate is almost 100%. 0.72 mmol) (corresponding to a hydrocarbyloxysilane compound) was added, and a modification reaction was performed at 50 ° C. for 30 minutes. Thereafter, 2 mL of a 5 mass% solution of 2,6-di-t-butyl-p-cresol (BHT) in isopropanol was added to stop the reaction, followed by drying according to a conventional method to obtain a modified SBR. As a result of measuring the microstructure of the obtained modified polymer C, the amount of bonded styrene was 10% by mass, the amount of vinyl bond in the butadiene portion was 40%, and the peak molecular weight was 200,000.

<Rolling resistance>
Each tire was mounted on a rim, filled with internal pressure, a maximum load specified for each tire was applied, and a rolling resistance value was measured under a drum rotation speed of 100 km / h. The evaluation results are indicated by an index with the tire described in Comparative Example 1 as 100, with the values for each tire being the reciprocal. It means that rolling resistance performance is so good that this index value is large. The obtained results are also shown in Table 1.

<Snow performance>
4 tires are mounted on a 1600cc class passenger car, and the passenger car is driven on a general asphalt road for 200km, and then the tire is locked on a -1 ° C icy / snow road surface from 40km / hr to brake until stopping. The distance was measured and indexed with the braking distance of the tire of Comparative Example 1 as 100. The larger the index value, the better the performance on icy and snowy road surfaces. The obtained results are also shown in Table 1.

<Wet performance>
The tire was mounted on a 2000 cc 4WD vehicle, and in the actual vehicle test on a wet road surface, the steering stability was expressed by the driver's feeling score, and the tire feeling score of Comparative Example 1 was shown as an index. The larger the index value, the better the performance on the wet road surface. The obtained results are also shown in Table 1.

* 1: RSS # 4
* 2: Latex acid coagulated isonicotinohydrazide modified NR
* 3: Latex acid coagulation 3- (dimethylamino) propane hydrazide modified NR
* 4: Cup lamp raw material 3- (dimethylamino) propane hydrazide modified NR
* 5: Cup lamp raw material 4- (tributyltin) butanehydrazide modified NR
* 6: “SBR1500” manufactured by JSR Corporation.
* 7: N, N-bis (trimethylsilyl) aminopropylmethyldiethoxysilane modified styrene butadiene rubber * 8: "BR01" manufactured by JSR Corporation
※ _{9: C} 9 resin (Nippon Petrochemicals Co., Ltd., trade name: Neo polymer 140)
* 10: Dicyclopentadiene resin (manufactured by Zeon Corporation, trade name: Quinton 1105)
※ _11: C 5 ~C _9-based resin (ExxonMobil Chemical Co., Ltd., trade name: ECR213)
* 12: Silica (BET specific surface area 205 m ² / g) (manufactured by Tosoh Silica Co., Ltd., trade name: Nipsil AQ)
* 13: Carbon black (N220 (ISAF)) (Asahi Carbon Co., Ltd., trade name: # 80)

  From Table 1, it can be seen that the rubber composition of the present invention is excellent in wet property and snow property when used as a tread rubber of a tire, and further improved in rolling resistance.

Claims (5)

In the rubber composition containing the rubber component (A) and the petroleum hydrocarbon resin (B),
The rubber component (A) contains 50% by mass or more of modified natural rubber and 50% by mass or less of styrene-butadiene rubber, and the petroleum hydrocarbon resin (B) with respect to 100 parts by mass of the rubber component (A). ) Is 5 to 50 parts by mass.   The rubber composition according to claim 1, wherein the modified natural rubber is obtained by adding a polar group-containing hydrazide compound to a natural rubber molecule in a natural rubber raw material.   The rubber composition according to claim 1 or 2, wherein the styrene-butadiene rubber is modified with a hydrocarbyloxysilane compound. The petroleum hydrocarbon resin (B), C ₅ resins, C ₅ -C ₉ resins, of claims 1 to 3 is at least one selected from the group consisting of C ₉ resins, and dicyclopentadiene resins The rubber composition as described in any one of Claims. A tire comprising the rubber composition according to any one of claims 1 to 4 as a tread rubber.