JPS63280750A - Interliner rubber composition for tire - Google Patents

Interliner rubber composition for tire

Info

Publication number
JPS63280750A
JPS63280750A JP11474987A JP11474987A JPS63280750A JP S63280750 A JPS63280750 A JP S63280750A JP 11474987 A JP11474987 A JP 11474987A JP 11474987 A JP11474987 A JP 11474987A JP S63280750 A JPS63280750 A JP S63280750A
Authority
JP
Japan
Prior art keywords
rubber
tire
rubber composition
interliner
inner liner
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP11474987A
Other languages
Japanese (ja)
Inventor
Yasushi Kikuchi
菊地 也寸志
Kazuyoshi Kayama
和義 加山
Takao Muraki
孝夫 村木
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Yokohama Rubber Co Ltd
Original Assignee
Yokohama Rubber Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Yokohama Rubber Co Ltd filed Critical Yokohama Rubber Co Ltd
Priority to JP11474987A priority Critical patent/JPS63280750A/en
Publication of JPS63280750A publication Critical patent/JPS63280750A/en
Pending legal-status Critical Current

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  • Compositions Of Macromolecular Compounds (AREA)

Abstract

PURPOSE:To provide an interliner rubber composition for tire, containing a halogenated butyl rubber and a polyisoprene rubber having high 3,4-bond content, and having high air permeation resistance, excellent processability and good adhesivity to other part of a tire. CONSTITUTION:The objective interliner rubber composition especially suitable for low-fuel cost tire to be used at a high air pressure is produced by compounding (A) 20-90pts.wt. of a chlorinated butyl rubber having a chlorine content of 1-1.4wt.% and an unsaturation degree of 1.5-2mol.% or a brominated butyl rubber having a bromine content of 1.7-2.3wt.% and unsaturation degree of 1.5-2mol.% with (B) 10-80pts.wt. of a polyisoprene rubber having a 3,4-bond content of 40-80% (the sum of A and B is 100pts.wt.) and, if necessary, compounding the above rubber components with (C) <=30pts.wt. of a diene rubber (e.g. natural rubber and high-cis polyisoprene rubber).

Description

【発明の詳細な説明】 〔発明の技術分野〕 本発明は、耐空気透過性が良好で、圧延作業性、成形作
業性等の加工性に優れかつタイヤの他の部材との接着性
が良好なタイヤ用インナーライナーゴム組成物に関する
[Detailed Description of the Invention] [Technical Field of the Invention] The present invention has good air permeation resistance, excellent workability such as rolling workability and molding workability, and good adhesion to other members of the tire. The present invention relates to an inner liner rubber composition for tires.

〔従来技術〕[Prior art]

近年、省エネルギーに対する社会的要請が強く、自動車
においてはタイヤの転勤抵抗の低減が省燃費に直結する
ため、この転勤抵抗の低減が強く望まれている。この転
勤抵抗の低減には、タイヤ各部材、特にトレッド部のヒ
ステリシスロスの低減あるいはタイヤ自身の軽量化、ま
たタイヤの使用内圧の高空気圧化が有効であることが、
一般に知られている。この軽量化という課題にとって、
インナーライナーのゲージダウンは非常に有効である。
In recent years, there has been a strong social demand for energy conservation, and in the case of automobiles, a reduction in the rolling resistance of tires is directly linked to fuel efficiency, so there is a strong desire to reduce this rolling resistance. In order to reduce this rolling resistance, it is effective to reduce hysteresis loss in each tire component, especially in the tread, to reduce the weight of the tire itself, and to increase the internal pressure used in the tire.
generally known. For this weight reduction issue,
Gauging down the inner liner is very effective.

また、タイヤ使用内圧の高空気圧化にとって、空気圧の
低下を極力押さえる必要がある。上記のインナーライナ
ーのゲージダウンにとっても、タイヤ空気圧の低下防止
にとっても空気透過率を極力低く押さえる必要がある。
Furthermore, in order to increase the internal pressure of tires used, it is necessary to suppress the decrease in air pressure as much as possible. It is necessary to keep the air permeability as low as possible both for reducing the gauge of the inner liner mentioned above and for preventing a drop in tire air pressure.

この空気圧の低下を抑えるためには、インナーライナー
のゴム組成物の空気透過率を低くすることが有効である
。このインナーライナーゴム組成物の空気透過率は、使
用するポリマーの空気透過率の高低に左右することが良
く知られている。昔から空気透過率の低いエラストマー
としてブチルゴムが知られ、インナーチューブにはこの
ブチルゴムが使用されている。ところが、このブチルゴ
ムは他のジエン系ゴムとの共加硫性が著しく悪く、また
他ゴムとの接着性が著しく悪いため、前述のインナーラ
イナーには使用することができない。そこで他のジエン
系ゴムとの共加硫性を改良したハロゲン化ブチルゴムが
このインナーライナー用ゴム組成物に使用されている。
In order to suppress this decrease in air pressure, it is effective to lower the air permeability of the rubber composition of the inner liner. It is well known that the air permeability of this inner liner rubber composition depends on the air permeability of the polymer used. Butyl rubber has long been known as an elastomer with low air permeability, and this butyl rubber is used for inner tubes. However, this butyl rubber has extremely poor co-vulcanization with other diene rubbers and extremely poor adhesion with other rubbers, so it cannot be used for the above-mentioned inner liner. Therefore, halogenated butyl rubber with improved covulcanizability with other diene rubbers is used in this inner liner rubber composition.

ところが、このハロゲン化ブチルゴムとても他のジエン
系ゴムとの接着性が悪く、この接着性を改良するために
、天然ゴムのようなジエン系ゴムとブレンドするのが一
般的である。しかし、この場合は、空気透過率の上昇は
避けられない。また特開昭59−168046では1.
2ビニル結合を70%以上有するポリブタジェンゴムと
ハロゲン化ブチルゴムとのブレンドが開示されているが
、この場合も天然ゴムやポリブタジェンゴムとのブレン
ドはどではないが、空気透過率が上昇してしまう。また
100%ハロゲン化ブチルゴムよりなるインナーライナ
ーゴム組成物は、混合時の安定性が悪いこと、圧延時の
寸法安定性が悪いこと、また未加硫の粘着性が悪いため
、この粘着性不足に起因するタイヤ加硫時の故障が発生
しやすい等の欠点を有している。また、特開昭60−2
12445にはエーテル結合を有する不飽和共重合体を
用いたインナーライナーゴム組成物が開示されているが
、このようなエーテル結合を有する共重合体は確かに空
気透過率は低いが透湿性が大きい欠点がある。
However, this halogenated butyl rubber has very poor adhesion to other diene rubbers, and in order to improve this adhesion, it is common to blend it with a diene rubber such as natural rubber. However, in this case, an increase in air permeability is unavoidable. Also, in JP-A-59-168046, 1.
Blends of polybutadiene rubber having 70% or more of 2-vinyl bonds and halogenated butyl rubber have been disclosed, but in this case as well, air permeability increases, although blends with natural rubber or polybutadiene rubber do not. Resulting in. In addition, inner liner rubber compositions made of 100% halogenated butyl rubber have poor stability during mixing, poor dimensional stability during rolling, and poor tackiness when unvulcanized. This has disadvantages such as the tendency for failures to occur during tire vulcanization. Also, JP-A-60-2
12445 discloses an inner liner rubber composition using an unsaturated copolymer having an ether bond, and although such a copolymer having an ether bond does have a low air permeability, it has a high moisture permeability. There are drawbacks.

タイヤにとってこの透湿性の悪さはワイヤー接着性を低
下し、耐久性を低下させるので好ましくない 以上のように、空気透過率が低く、他のジエン系ゴムと
の接着が良好でかつ加工性の良好な上にエーテル結合を
有しないようなインナーライナーゴム組成物は得られて
いない。したがって、このようなゴム組成物の出現が望
まれていた。
This poor moisture permeability is undesirable for tires because it reduces wire adhesion and durability.As mentioned above, it has low air permeability, good adhesion with other diene rubbers, and good processability. Moreover, no inner liner rubber composition having no ether bond has been obtained. Therefore, the appearance of such a rubber composition has been desired.

〔発明の目的〕[Purpose of the invention]

本発明は、空気透過率が低く、混合、圧延、成形時の加
工性が良好で、かつタイヤの他の部材との接着性が良好
なるイ”ンナーライナー用ゴム組成物を提供することを
目的とし、特に乗用車あるいはトラック・バス用のチュ
ーブレスタイヤに利用される。なかでも高空気圧にて使
用される低燃費タイヤに好適なインナーライナーゴム組
成物を提供するものである。
An object of the present invention is to provide a rubber composition for an inner liner that has low air permeability, good workability during mixing, rolling, and molding, and good adhesion to other parts of a tire. The present invention provides an inner liner rubber composition that is particularly suitable for tubeless tires for passenger cars, trucks, and buses.In particular, the present invention provides an inner liner rubber composition suitable for fuel-efficient tires used at high air pressures.

〔発明の構成〕[Structure of the invention]

本発明は、タイヤのインナーライナーゴムとして、ゴム
成分100重量部中、ハロゲン化ブチルゴム20〜90
重量部、3,4結合量が40〜80%のポリイソプレン
ゴム(以下3,4ポリイソプレンゴムという)10〜8
0重量部よりなることを特徴とするタイヤ用インナーラ
イナーゴム組底物を要旨とするものである。
The present invention uses 20 to 90 parts of halogenated butyl rubber in 100 parts by weight of the rubber component as an inner liner rubber for tires.
Parts by weight, polyisoprene rubber with a 3,4 bond content of 40 to 80% (hereinafter referred to as 3,4 polyisoprene rubber) 10 to 8
The gist of the present invention is to provide an inner liner rubber assembly for tires characterized by comprising 0 parts by weight.

本発明に使用するハロゲン化ブチルゴムは塩素化ブチル
ゴムあるいは臭素化ブチルゴムで、塩素含有量が1.0
〜1.4重量%、不飽和度1.5〜2.0モル%の塩素
化ブチルゴムかあるいは臭素含有量1.7〜2.3重量
%、不飽和度1.5〜2゜0モル%の臭素化ブチルゴム
である。塩素含有量は、1.0〜1.4重量%、臭素含
有量1.7〜2゜3%の範囲のものである。各々下限よ
り少ないと他のジエン系ゴムとの接着性が劣り、上限よ
り多くなるとポリマーの安定性が悪く、混合時スコーチ
トラブルを発生しやすくなる。不飽和度は1.5〜2.
0モル%の範囲であって、1.5モル%未満であると他
のジエン系ゴムとの接着が悪< 、2.0モル%を越え
ると空気透過率が上昇する。
The halogenated butyl rubber used in the present invention is chlorinated butyl rubber or brominated butyl rubber, and has a chlorine content of 1.0.
Chlorinated butyl rubber with ~1.4% by weight and unsaturation level of 1.5-2.0 mol% or bromine content of 1.7-2.3% by weight and unsaturation level of 1.5-2.0 mol% brominated butyl rubber. The chlorine content ranges from 1.0 to 1.4% by weight, and the bromine content ranges from 1.7 to 2.3%. If each amount is less than the lower limit, the adhesion with other diene rubbers will be poor, and if it is more than the upper limit, the stability of the polymer will be poor and scorch troubles will easily occur during mixing. The degree of unsaturation is 1.5-2.
If the amount is less than 1.5 mol%, adhesion with other diene rubbers will be poor; if it exceeds 2.0 mol%, the air permeability will increase.

また、本発明で使用するポリイソプレンゴムは、3,4
結合量が40〜80%の範囲にあるものである。一般の
合成ポリイソプレンゴムは、シス含有量が85%以上と
極めて高いのが特徴であり、分子鎖中の3.4結合量は
10%以下と少ないものである。しかるに本発明のポリ
イソプレンゴムは、3,4結合量が、40〜80%と多
いものである。空気透過率を低くするためには主鎖中の
二重結合を少なくして主鎖の分子運動を極力抑え、かつ
側鎖に大きな基を導入することが有効である。その点、
3,4結合Q多いポリイソプレンゴムは理想的な化学構
造をしている。ただし、3.4結合量は、40〜80%
の範囲にあるもので、40%未満では空気透過率が高く
なってしまい、一方80%を越えると空気透過率は低い
が低温特性が悪化し、好ましくない。
Moreover, the polyisoprene rubber used in the present invention is 3,4
The amount of binding is in the range of 40 to 80%. General synthetic polyisoprene rubber is characterized by an extremely high cis content of 85% or more, and the amount of 3.4 bonds in the molecular chain is as small as 10% or less. However, the polyisoprene rubber of the present invention has a high 3,4 bond content of 40 to 80%. In order to lower the air permeability, it is effective to reduce the number of double bonds in the main chain to suppress the molecular movement of the main chain as much as possible, and to introduce large groups into the side chains. That point,
Polyisoprene rubber with a large number of 3,4 bonds has an ideal chemical structure. However, the amount of 3.4 binding is 40-80%
If it is less than 40%, the air permeability will be high, while if it exceeds 80%, the air permeability will be low but the low temperature characteristics will deteriorate, which is not preferable.

また、ハロゲン化ブチルゴムと3.4ポリイソプレンゴ
ムの外に更にジエン系ゴムをブレンドしてもよい。この
ジエン系ゴムとして天然ゴム、高シスポリイソプレンゴ
ム、ポリブタジェンゴム、スチレン−ブタジェン共重合
ゴム、エチレン−プロピレン三元共重合ゴムがあげられ
る。添加する量は、ハロゲン化ブチルゴムと3.4ポリ
イソプレンゴム合計100 ffi量部に対して、30
重量部以下が好ましい。
Further, a diene rubber may be further blended in addition to the halogenated butyl rubber and the 3.4 polyisoprene rubber. Examples of the diene rubber include natural rubber, high-cis polyisoprene rubber, polybutadiene rubber, styrene-butadiene copolymer rubber, and ethylene-propylene terpolymer rubber. The amount to be added is 30 parts per 100 parts of halogenated butyl rubber and 3.4 polyisoprene rubber in total.
Parts by weight or less are preferred.

上記3,4結合ポリイソプレンゴムのブレンド量は、1
0〜80重量部である。10重量部未満であると加工性
および接着性の改良効果がない。逆に80重量部を越え
ると空気透過率が上昇し、問題である。また、おなじく
ジエン系ゴムを30重量部をこえてブレンドすると空気
透過率が上昇しすぎ、いずれもインナーライナー用ゴム
組成物として適当ではない。
The blending amount of the above 3,4 bond polyisoprene rubber is 1
It is 0 to 80 parts by weight. If it is less than 10 parts by weight, there will be no improvement in processability and adhesiveness. On the other hand, if it exceeds 80 parts by weight, the air permeability increases, which is a problem. Similarly, if more than 30 parts by weight of diene rubber is blended, the air permeability will increase too much, and neither is suitable as a rubber composition for an inner liner.

〔実施例〕〔Example〕

以下実施例にもとづいて説明する。 The following will be explained based on examples.

表1の配合表にしたがい亜鉛華、促進剤、硫黄以外の配
合剤を1.7リソトルのB型バンバIJ−ミー1−サー
にて4分間混合後排出した。次いで8インチ試験用ロー
ル機にて、残りの亜鉛華、促進剤、硫黄を添加し4分間
混練し、各々のゴム組成物を調整した。また、未加硫ゴ
ノ、を160°Cで20分間プレス加硫し試験用ゴム片
を作成し、以下の試験方法にしたがって測定した。
The ingredients other than zinc white, accelerator, and sulfur were mixed for 4 minutes in a 1.7 lsotorl Bamba IJ-Mieser according to the recipe shown in Table 1, and then discharged. Next, using an 8-inch test roll machine, the remaining zinc white, accelerator, and sulfur were added and kneaded for 4 minutes to prepare each rubber composition. In addition, test rubber pieces were prepared by press-vulcanizing unvulcanized rubber at 160°C for 20 minutes, and measured according to the following test method.

試験方法は以下のとおりである。The test method is as follows.

(引張強さ、伸び) JIS K6301に準拠(スコ
ーチ時間)  JIS K2SO3に準1処(通気度)
  ASTM 01434−82に準拠し、測定。
(Tensile strength, elongation) Compliant with JIS K6301 (scorch time) JIS K2SO3 semi-1 (air permeability)
Measured according to ASTM 01434-82.

但し、気体としては空気を用い、 30’c雰囲気下で測定。However, using air as the gas, Measured under 30'c atmosphere.

(タッキネス、密着力) 東洋精機盟PICMATACKメーターを用い圧着荷!
Tf500gf 、圧着時間10秒の条件で密着させ1
25CI11/分の剥離速度で剥離し、その時の最大 荷重を示す。
(Tackiness, adhesion force) Crimp loads using Toyo Seikimei PICMATACK meter!
Tf500gf, crimping time 10 seconds, 1
Peeling was performed at a peeling rate of 25CI11/min, and the maximum load at that time is shown.

(対カーカスゴム接着) 天然ゴム/スチレン−ブタジェン 共m合ゴム系のカーカス用ゴム組 酸物と各試験ゴム組成物を未加硫 時に貼り合わせ50kgf /cjAの圧力下で160
℃で20分間プレス加硫し 250幅の試験片を作成し、50龍/ 分の剥離速度で剥離し、その時の 平均の剥離力を算出。
(Adhesion to carcass rubber) Natural rubber/styrene-butadiene co-molar rubber-based carcass rubber compound acid and each test rubber composition were bonded together while unvulcanized under a pressure of 50 kgf/cjA at 160 kgf/cjA.
A test piece with a width of 250 mm was prepared by press vulcanization at ℃ for 20 minutes, and the sample was peeled off at a peeling speed of 50 mm/min, and the average peeling force at that time was calculated.

(未加硫ゴムの引張応力) 加硫ゴムシートの代わりに未加硫 ゴムシートを用いてJIS K6301の方法で測定。(Tensile stress of unvulcanized rubber) Unvulcanized instead of vulcanized rubber sheet Measured using a rubber sheet according to JIS K6301 method.

(未加硫ゴムの寸法安定性) 137M 02230−78にもとづく試験を行い、ダ
イスウェルにより比較。
(Dimensional stability of unvulcanized rubber) A test was conducted based on 137M 02230-78 and compared by die swell.

(本頁以下余白) 表2に示す物性から明らかなごとく本発明の実施例1〜
5は、臭素化ブチルゴム100重量部よりなる比較例6
に比しいずれもタッキネスが向上しており、またカーカ
ス材との接着性も大幅に向上していることがわかる。更
に未加硫ゴムの引張応力が高いためタイヤ成形時の寸法
安定性の点でも有利である。また、比較例7および8は
、カーカス材接着と未加硫ゴムの引張応力を上げるため
に天然ゴムをブレンドした例であるが、この場合は通気
度の悪化とスコーチ時間の短縮が大きくなっている。一
方、実施例のゴム組成物は、耐空気透過性が良好で、ま
た密着力に優れ、かつカーカス材と接着力に優れている
ことが明らかである。
(Margin below this page) As is clear from the physical properties shown in Table 2, Examples 1 to 1 of the present invention
5 is Comparative Example 6 consisting of 100 parts by weight of brominated butyl rubber.
It can be seen that the tackiness is improved in all cases compared to the above, and the adhesion to the carcass material is also significantly improved. Furthermore, since the unvulcanized rubber has a high tensile stress, it is advantageous in terms of dimensional stability during tire molding. Comparative Examples 7 and 8 are examples in which natural rubber was blended to increase the adhesion of the carcass material and the tensile stress of the unvulcanized rubber. There is. On the other hand, it is clear that the rubber compositions of Examples have good air permeation resistance, excellent adhesion, and excellent adhesion to carcass materials.

〔発明の効果〕〔Effect of the invention〕

以上のごとく本発明のタイヤ用インナーライナーゴム組
底物は、空気透過性が低く、すなわち空気を通し離く、
密着性が良好で、未加硫ゴムの引張応力が高く、即ちタ
イヤ成形時の寸法安定性が良く、かつカーカス材との接
着が良好なる優れた性能を有しており、タイヤのインナ
ーライナーとして極めて好適である。
As described above, the tire inner liner rubber assembly of the present invention has low air permeability, that is, it allows air to pass through it.
It has excellent adhesion, high tensile stress of unvulcanized rubber, good dimensional stability during tire molding, and good adhesion to carcass material, making it suitable for use as an inner liner for tires. Very suitable.

Claims (1)

【特許請求の範囲】[Claims] タイヤのインナーライナーゴムとして、ゴム成分100
重量部中、ハロゲン化ブチルゴム20〜90重量部、3
,4結合量が40〜80%のポリイソプレンゴム10〜
80重量部よりなることを特徴とするタイヤ用インナー
ライナーゴム組成物。
Rubber component 100 as inner liner rubber for tires
In parts by weight, 20 to 90 parts by weight of halogenated butyl rubber, 3
, 4 Polyisoprene rubber with a bond content of 40 to 80% 10 to
An inner liner rubber composition for tires comprising 80 parts by weight.
JP11474987A 1987-05-13 1987-05-13 Interliner rubber composition for tire Pending JPS63280750A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11474987A JPS63280750A (en) 1987-05-13 1987-05-13 Interliner rubber composition for tire

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11474987A JPS63280750A (en) 1987-05-13 1987-05-13 Interliner rubber composition for tire

Publications (1)

Publication Number Publication Date
JPS63280750A true JPS63280750A (en) 1988-11-17

Family

ID=14645713

Family Applications (1)

Application Number Title Priority Date Filing Date
JP11474987A Pending JPS63280750A (en) 1987-05-13 1987-05-13 Interliner rubber composition for tire

Country Status (1)

Country Link
JP (1) JPS63280750A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004276699A (en) * 2003-03-14 2004-10-07 Bridgestone Corp Pneumatic tire
JP2005171165A (en) * 2003-12-12 2005-06-30 Toyo Tire & Rubber Co Ltd Rubber composition for inner liner and pneumatic tire
JP2008127443A (en) * 2006-11-20 2008-06-05 Toyo Tire & Rubber Co Ltd Rubber composition for inner liner and pneumatic tire

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004276699A (en) * 2003-03-14 2004-10-07 Bridgestone Corp Pneumatic tire
JP2005171165A (en) * 2003-12-12 2005-06-30 Toyo Tire & Rubber Co Ltd Rubber composition for inner liner and pneumatic tire
JP4567322B2 (en) * 2003-12-12 2010-10-20 東洋ゴム工業株式会社 Rubber composition for inner liner and pneumatic tire
JP2008127443A (en) * 2006-11-20 2008-06-05 Toyo Tire & Rubber Co Ltd Rubber composition for inner liner and pneumatic tire

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