JP2016104626A - Pneumatic tire - Google Patents

Pneumatic tire Download PDF

Info

Publication number
JP2016104626A
JP2016104626A JP2016017395A JP2016017395A JP2016104626A JP 2016104626 A JP2016104626 A JP 2016104626A JP 2016017395 A JP2016017395 A JP 2016017395A JP 2016017395 A JP2016017395 A JP 2016017395A JP 2016104626 A JP2016104626 A JP 2016104626A
Authority
JP
Japan
Prior art keywords
tire
rubber layer
tread
tread rubber
thickness
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.)
Granted
Application number
JP2016017395A
Other languages
Japanese (ja)
Other versions
JP6033975B2 (en
Inventor
中田　広
Hiroshi Nakada
広 中田
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.)
Bridgestone Corp
Original Assignee
Bridgestone Corp
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 Bridgestone Corp filed Critical Bridgestone Corp
Priority to JP2016017395A priority Critical patent/JP6033975B2/en
Publication of JP2016104626A publication Critical patent/JP2016104626A/en
Application granted granted Critical
Publication of JP6033975B2 publication Critical patent/JP6033975B2/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C11/00—Tyre tread bands; Tread patterns; Anti-skid inserts
    • B60C11/0041—Tyre tread bands; Tread patterns; Anti-skid inserts comprising different tread rubber layers
    • B60C11/005—Tyre tread bands; Tread patterns; Anti-skid inserts comprising different tread rubber layers with cap and base layers

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Tires In General (AREA)

Abstract

PROBLEM TO BE SOLVED: To provide a pneumatic tire improved in uneven wear resistance of tread.SOLUTION: A tire uses, as a skeleton, a carcass extending in a toroidal shape between a pair of bead cores and has at least one circumferential belt layer and a tread on the outside of the carcass in the direction of tire diameter. In the tire, the tread is formed from a plurality of tread rubber layers, the dynamic modulus of elasticity of an outside tread rubber layer located on the furthest outside in the direction of tire diameter is higher than the dynamic modulus of elasticity of an inside tread rubber layer located on the furthest inside in the direction of tire diameter. The thickness of the inside tread rubber layer in a tread center area is less than the thickness of the inside tread rubber layer in an edge area of the circumferential belt layer in the direction of tire width. The position of the maximum thickness of the inside tread rubber layer is outside in the direction of tire width of a position corresponding to 80% width of the circumferential belt layer around a tire equator face.SELECTED DRAWING: Figure 1

Description

本発明は、トレッドの耐偏摩耗性能を向上した空気入りタイヤに関するものである。   The present invention relates to a pneumatic tire with improved uneven wear resistance performance of a tread.

従来、空気入りタイヤにおいては、種々の性能を同時に満足させるために、トレッドを２層のトレッドゴム層から形成する、いわゆるキャップ／ベース構造を適用することが行われている。   Conventionally, in a pneumatic tire, in order to satisfy various performances simultaneously, a so-called cap / base structure in which a tread is formed of two tread rubber layers has been applied.

例えば、特許文献１には、キャップゴム層およびベースゴム層の各々のゴム硬度（ハードネス）および硬度差を規制し、かつ、ベースゴム層を、途切れ部を隔ててタイヤ赤道面両側に配される一対のベースゴム片で形成するとともに、このベースゴム片のゴム厚さをタイヤ幅方向内側から外側に向かって増加させることにより、耐摩耗性を高く維持しながら、トレッド温度の上昇を抑制して耐久性を向上しうる重荷重用ラジアルタイヤが提案されている。
また、高速走行時の遠心力によるトレッドの径成長し、いわゆるタガ効果を発揮してタイヤ周方向剛性を確保するために周方向ベルト層をタイヤに適用することが行われている。 For example, in Patent Document 1, the rubber hardness (hardness) and the hardness difference of each of the cap rubber layer and the base rubber layer are regulated, and the base rubber layer is disposed on both sides of the tire equatorial plane with a break. While forming with a pair of base rubber pieces and increasing the rubber thickness of this base rubber piece from the inside to the outside in the tire width direction, the increase in tread temperature is suppressed while maintaining high wear resistance. A heavy duty radial tire capable of improving durability has been proposed.
In addition, a circumferential belt layer is applied to a tire in order to increase the diameter of a tread due to centrifugal force during high-speed traveling and to exhibit a so-called tagging effect to ensure tire circumferential rigidity.

２００３−１２７６１３号公報No. 2003-127613

ところが、周方向ベルト層を適用したタイヤにおいて、タイヤ赤道面付近のトレッドでの摩耗が早く進行し、トレッドに偏摩耗が発生するという問題が生じていた。
そこで、本発明は、トレッドにキャップ／ベース構造を適用した空気入りタイヤの耐偏摩耗特性を向上させることを目的とする。 However, in the tire to which the circumferential belt layer is applied, there is a problem that wear on the tread near the tire equatorial plane proceeds quickly and uneven wear occurs on the tread.
Therefore, an object of the present invention is to improve the uneven wear resistance of a pneumatic tire in which a cap / base structure is applied to a tread.

本発明の要旨は、以下のとおりである。
（１）１対のビードコア間でトロイド状に延びるカーカスを骨格とし、このカーカスのタイヤ径方向外側に、少なくとも１層の周方向ベルト層およびトレッドを具えるタイヤにおいて、
前記トレッドを複数のトレッドゴム層から形成し、
タイヤ径方向最外側に位置する外側トレッドゴム層の動的弾性率が、タイヤ径方向最内側に位置する内側トレッドゴム層の動的弾性率より高く、
トレッドセンター領域における前記内側トレッドゴム層の厚さが、前記周方向ベルト層のタイヤ幅方向端部領域における前記内側トレッドゴム層の厚さよりも薄く、
前記内側トレッドゴム層の厚さが最大となる位置は、タイヤ赤道面を中心に前記周方向ベルト層の幅の８０％の位置よりタイヤ幅方向外側にある、
ことを特徴とする空気入りタイヤ。 The gist of the present invention is as follows.
(1) In a tire including a carcass extending in a toroidal shape between a pair of bead cores and having at least one circumferential belt layer and a tread on the outer side in the tire radial direction of the carcass,
Forming the tread from a plurality of tread rubber layers;
The dynamic elastic modulus of the outer tread rubber layer located on the outermost side in the tire radial direction is higher than the dynamic elastic modulus of the inner tread rubber layer located on the innermost side in the tire radial direction,
The thickness of the inner tread rubber layer in the tread center region is thinner than the thickness of the inner tread rubber layer in the tire width direction end region of the circumferential belt layer,
The position where the thickness of the inner tread rubber layer is maximized is on the outer side in the tire width direction from the position of 80% of the width of the circumferential belt layer around the tire equatorial plane.
A pneumatic tire characterized by that.

（２）前記内側トレッドゴム層の厚さが、タイヤ赤道面からトレッド接地端に向かって漸増することを特徴とする上記（１）に記載の空気入りタイヤ。 (2) The pneumatic tire according to (1) above, wherein the thickness of the inner tread rubber layer gradually increases from the tire equatorial plane toward the tread ground contact edge.

（３）前記内側トレッドゴム層の厚さが最大となる位置は、前記周方向ベルト層のタイヤ幅方向端よりタイヤ幅方向外側にあることを特徴とする上記（１）または（２）に記載の空気入りタイヤ。 (3) The position at which the thickness of the inner tread rubber layer is maximum is located on the outer side in the tire width direction of the end of the circumferential belt layer in the tire width direction. Pneumatic tires.

（４）前記内側トレッドゴム層の厚さが増加開始する位置は、前記周方向ベルト層の幅の４０％よりタイヤ幅方向外側にあることを特徴とする上記（１）〜（３）のいずれかに記載の空気入りタイヤ。 (4) Any of the above (1) to (3), wherein the position where the thickness of the inner tread rubber layer starts to increase is located on the outer side in the tire width direction from 40% of the width of the circumferential belt layer. The pneumatic tire according to Crab.

（５）前記外側トレッドゴム層の動的弾性率が８．０ＭＰａ〜２０ＭＰａであり、
前記内側トレッドゴム層の動的弾性率が１．０ＭＰａ〜７．０ＭＰａである、
ことを特徴とする上記（１）〜（４）のいずれかに記載の空気入りタイヤ。 (5) The dynamic elastic modulus of the outer tread rubber layer is 8.0 MPa to 20 MPa,
The dynamic elastic modulus of the inner tread rubber layer is 1.0 MPa to 7.0 MPa.
The pneumatic tire according to any one of (1) to (4) above, wherein

（６）前記外側トレッドゴム層の動的弾性率が、温度２５℃、周波数５２Ｈｚ、歪２％時において、前記内側トレッドゴム層の動的弾性率の１．５倍以上３．５倍以下であることを特徴とする上記（１）〜（５）のいずれかに記載の空気入りタイヤ。 (6) The dynamic elastic modulus of the outer tread rubber layer is 1.5 to 3.5 times the dynamic elastic modulus of the inner tread rubber layer at a temperature of 25 ° C., a frequency of 52 Hz, and a strain of 2%. The pneumatic tire according to any one of (1) to (5) above, wherein

本発明により、トレッドの耐偏摩耗性能を向上した空気入りタイヤを提供することができる。   According to the present invention, it is possible to provide a pneumatic tire with improved uneven wear resistance performance of the tread.

本発明の空気入りタイヤの半部の幅方向断面図である。It is width direction sectional drawing of the half part of the pneumatic tire of this invention. タイヤ転動時のトレッドの変形を説明するための図である。It is a figure for demonstrating deformation | transformation of the tread at the time of tire rolling. 従来の空気入りタイヤの半部の幅方向断面図である。It is sectional drawing of the width direction of the half part of the conventional pneumatic tire.

以下に、図面を参照しながら本発明の空気入りタイヤを詳細に説明する。
図１に本発明の空気入りタイヤのトレッド半部の幅方向断面図を示す。本発明の空気入りタイヤ１０は、１対のビードコア間でトロイド状に延びるカーカス２を骨格とし、このカーカス２のタイヤ径方向外側に、２層の周方向ベルト層３ａ、３ｂと２層の傾斜ベルト層４ａ、４ｂとトレッド６とを配置してなる。周方向ベルト層３ａ、３ｂは、タイヤ赤道面ＣＬに沿って延びる複数のコードをゴムで被覆したものである。なお、周方向ベルト層３ａ、３ｂは、複数のコードをゴムで被覆した狭幅ストリップをタイヤ周方向に螺旋巻回することで形成されている。傾斜ベルト層４ａ、４ｂは、タイヤ赤道面ＣＬに対して斜めに、かつ層間で互いに交差する向きに延びる複数のコードをゴムで被覆したものである。
なお、カーカス２、周方向ベルト層３ａ、３ｂおよび傾斜ベルト層４ａ、４ｂは、図示例に限定されるものではない。例えば、カーカスを２枚のカーカスプライから構成することもできるし、１層の周方向ベルト層を配置することもできるし、傾斜ベルト層のタイヤ径方向外側に周方向ベルト層を配置することもできる。また、周方向ベルト層３ａ、３ｂは、波状に型付けしたコードやハイエロンゲーションコードを用いることが好ましい。 Hereinafter, the pneumatic tire of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a cross-sectional view in the width direction of the tread half of the pneumatic tire of the present invention. The pneumatic tire 10 of the present invention has a carcass 2 extending in a toroidal shape between a pair of bead cores as a skeleton, and two circumferential belt layers 3a and 3b and two inclined layers on the outer side in the tire radial direction of the carcass 2. The belt layers 4a and 4b and the tread 6 are arranged. The circumferential belt layers 3a and 3b are made by coating a plurality of cords extending along the tire equatorial plane CL with rubber. The circumferential belt layers 3a and 3b are formed by spirally winding a narrow strip in which a plurality of cords are covered with rubber in the tire circumferential direction. The inclined belt layers 4a and 4b are made of rubber coated with a plurality of cords extending obliquely with respect to the tire equatorial plane CL and extending in directions intersecting with each other between the layers.
The carcass 2, the circumferential belt layers 3a and 3b, and the inclined belt layers 4a and 4b are not limited to the illustrated examples. For example, the carcass can be composed of two carcass plies, one circumferential belt layer can be arranged, or the circumferential belt layer can be arranged outside the inclined belt layer in the tire radial direction. it can. The circumferential belt layers 3a and 3b are preferably made of wavy cords or high elongation cords.

トレッド６は複数のトレッドゴム層、図示例では、タイヤ径方向最外側に位置する外側トレッドゴム層であるキャップゴム層６Ｃと、タイヤ径方向最内側に位置する内側トレッドゴム層であるベースゴム層６Ｂとの２層から形成される、いわゆるキャップ／ベース構造である。
トレッド６を３層以上のトレッドゴム層で形成する場合、タイヤ径方向最外側の外側トレッドゴム層と、タイヤ径方向最内側の内側トレッドゴム層との動的弾性率を規定し、内側トレッドゴム層の厚さを規定するものとする。なお、図１に示すように、トレッド６を２層のトレッドゴム層で形成することが好適であり、以下では、トレッド６を２層のトレッドゴム層で形成する場合について説明するが、本発明はこれに限定されない。 The tread 6 includes a plurality of tread rubber layers, in the illustrated example, a cap rubber layer 6C that is an outer tread rubber layer positioned on the outermost side in the tire radial direction, and a base rubber layer that is an inner tread rubber layer positioned on the innermost side in the tire radial direction. This is a so-called cap / base structure formed from two layers with 6B.
When the tread 6 is formed of three or more tread rubber layers, the dynamic elastic modulus between the outermost tread rubber layer in the tire radial direction and the inner tread rubber layer in the innermost tire radial direction is defined, and the inner tread rubber is defined. The layer thickness shall be specified. As shown in FIG. 1, it is preferable to form the tread 6 with two tread rubber layers. Hereinafter, the case where the tread 6 is formed with two tread rubber layers will be described. Is not limited to this.

キャップゴム層６Ｃの動的弾性率が、ベースゴム層６Ｂの動的弾性率より高く、トレッドセンター領域におけるベースゴム層６Ｂの厚さが、周方向ベルト層３ａ、３ｂのタイヤ幅方向端部領域におけるベースゴム層６Ｂの厚さよりも薄く、さらに、ベースゴム層６Ｂの厚さが最大となる位置Ｍは、タイヤ赤道面ＣＬを中心に周方向ベルト層３ａ、３ｂの幅の８０％の位置よりタイヤ幅方向外側にあることが肝要である。
なお、「トレッドセンター領域」とは、タイヤ赤道面ＣＬを中心として、タイヤ幅方向にＷ／３以内の領域をいい（Ｗ：トレッド半幅）、「トレッドセンター領域におけるベースゴム層６Ｂの厚さ」とは、当該領域におけるベースゴム層６Ｂの平均厚さを意味する。同様に、「周方向ベルト層３ａ、３ｂのタイヤ幅方向端部領域」とは、周方向ベルト層３ａ、３ｂのタイヤ幅方向端３ａｅ、３ｂｅを中心として、タイヤ幅方向にＢ／５以内の領域をいい（Ｂ：周方向ベルト層の半幅）、「周方向ベルト層３ａ、３ｂのタイヤ幅方向端部領域におけるベースゴム層６Ｂの厚さ」とは、当該領域におけるベースゴム層６Ｂの平均厚さを意味する。また、複数の周方向ベルト層３ａ、３ｂが配置されている場合、最も幅が広い周方向ベルト層の幅を基準とするものとする。 The dynamic elastic modulus of the cap rubber layer 6C is higher than the dynamic elastic modulus of the base rubber layer 6B, and the thickness of the base rubber layer 6B in the tread center region is the end region in the tire width direction of the circumferential belt layers 3a and 3b. The position M where the thickness of the base rubber layer 6B is smaller than the thickness of the base rubber layer 6B and the maximum thickness of the base rubber layer 6B is 80% of the width of the circumferential belt layers 3a and 3b with the tire equatorial plane CL as the center. It is important to be outside in the tire width direction.
The “tread center region” refers to a region within W / 3 in the tire width direction around the tire equatorial plane CL (W: half width of the tread). “Thickness of the base rubber layer 6B in the tread center region” Means the average thickness of the base rubber layer 6B in the region. Similarly, “the end regions in the tire width direction of the circumferential belt layers 3a and 3b” are within the range of B / 5 in the tire width direction with the tire width direction ends 3ae and 3be of the circumferential belt layers 3a and 3b as the center. The region is referred to as (B: half width of the circumferential belt layer), and “the thickness of the base rubber layer 6B in the end region in the tire width direction of the circumferential belt layers 3a and 3b” means the average of the base rubber layer 6B in the region It means thickness. Further, when a plurality of circumferential belt layers 3a and 3b are arranged, the width of the circumferential belt layer having the widest width is used as a reference.

以下に本発明の作用を説明する。
タイヤの転動時には、図２（ａ）に示す偏芯変形と図２（ｂ）に示すリング変形という２つの変形が複合している。図中、点線は変形前のタイヤの外形、実線は転動時のタイヤの外形を表す。周方向ベルト層は高剛性であるため、荷重負荷時の形状保持効果（偏芯効果）が大きい。それゆえ、周方向ベルト層を有するタイヤでは、図２（ａ）に示すように、回転中心が偏り、タイヤ回転時のタイヤ側面形状が正円に近くなるので、図２（ｂ）に示すリング変形の場合と比較して、タイヤ接地部分の接地長が短くなり、接地圧が上昇する。この接地圧の上昇により、トレッドゴムが圧縮変形を受け易くなってゴムがタイヤ周方向に大きく変形することになる。このように、周方向ベルト層が配置されている領域のトレッドゴムは大きく変形する一方、周方向ベルト層が配置されていない領域、中でも、タイヤ赤道面を中心に周方向ベルト層の幅の８０％の位置よりタイヤ幅方向外側の領域（以下、「トレッドショルダー領域」という）では、タガ効果が十分に働かないため接地圧が急激に低下する。トレッドショルダー領域では、このような接地圧の低下により、トレッドゴムが圧縮変形を受け難く、ゴムがタイヤ周方向に変形しにくくなる。このように、トレッド幅方向における接地圧が不均一なことにより、トレッドに偏摩耗が生じていた。 The operation of the present invention will be described below.
At the time of rolling of the tire, two deformations, that is, eccentric deformation shown in FIG. 2A and ring deformation shown in FIG. 2B are combined. In the figure, the dotted line represents the outer shape of the tire before deformation, and the solid line represents the outer shape of the tire during rolling. Since the circumferential belt layer is highly rigid, the shape retention effect (eccentric effect) when loaded is great. Therefore, in a tire having a circumferential belt layer, as shown in FIG. 2 (a), the center of rotation is biased and the tire side surface shape during rotation of the tire is close to a perfect circle, so the ring shown in FIG. 2 (b) Compared to the case of deformation, the contact length of the tire contact portion is shortened, and the contact pressure increases. As the contact pressure increases, the tread rubber is easily subjected to compressive deformation, and the rubber is greatly deformed in the tire circumferential direction. As described above, the tread rubber in the region where the circumferential belt layer is disposed is greatly deformed, while the region where the circumferential belt layer is not disposed, particularly the width of the circumferential belt layer around the tire equatorial plane. In the region on the outer side in the tire width direction from the position of% (hereinafter referred to as “tread shoulder region”), the contact pressure does not sufficiently work and the contact pressure rapidly decreases. In the tread shoulder region, due to such a decrease in the contact pressure, the tread rubber is hardly subjected to compressive deformation, and the rubber is difficult to deform in the tire circumferential direction. Thus, uneven wear occurred in the tread due to the non-uniform contact pressure in the tread width direction.

そこで、本発明では、周方向ベルト層とトレッドゴムの変形との関係に着目し、トレッドの耐偏摩耗性能を向上すべく鋭意検討を行った。
トレッドゴムの変形はゴムの弾性率に比例するため、トレッドゴムを硬くすれば変形は減少する。特に、偏芯効果の大きいトレッドセンター領域のトレッドゴムの弾性率を大きくすれば、トレッドゴムの変形は減少する。しかしながら、単純に路面に接するトレッドゴムの弾性率を増加してゴムを硬くすると、トレッドゴムの変形を抑制することになるものの、トレッドパターンのブロック（陸部）がもげ易い等の不具合を招く。そこで、これらの不具合を招くことなく、効率的に弾性率を上げるために、トレッドにキャップ／ベース構造を適用し、トレッドセンター領域のベースゴム層の厚みをトレッドショルダー領域対比で薄くすることに想到した。以下、この理由を説明する。
キャップ／ベース構造では、一般的に、キャップゴム層には耐久性向上のために高弾性率のゴムを用い、ベースゴム層には低発熱性のために低弾性率のゴムを用いている。トレッドセンター領域において、低弾性率の軟らかいベースゴム層の厚みを減らすと、トレッドゴムゲージは変化しないので、高弾性率のキャップゴム層の厚みが増すこととなる。その結果、トレッドセンター領域において、ベースゴム層とキャップゴム層を合わせたトレッドゴム全体の弾性率を増加させることができる。同様に、トレッドショルダー領域では、低弾性率の軟らかいベースゴム層の厚みを増すことにより、ベースゴム層とキャップゴム層を合わせたトレッドゴム全体の弾性率を減少させることができる。
このように、接地圧の高いトレッドセンター領域において、トレッドゴムの弾性率を増加することでトレッドゴムの変形を抑制するとともに、接地圧の低いトレッドショルダー領域において、トレッドゴムの弾性率を減少することでトレッドゴムの変形を促進することにより、トレッドの動的弾性率に幅方向分布が生じる。すると、タイヤ幅方向に不均一なトレッドの接地圧を、タイヤ幅方向に不均一なトレッドの動的弾性率によって打ち消すことになり、トレッド幅方向のトレッドゴムの変形が均一化して、トレッドの偏摩耗が抑制される。 Therefore, in the present invention, paying attention to the relationship between the circumferential belt layer and the deformation of the tread rubber, intensive studies were conducted to improve the uneven wear resistance of the tread.
Since the deformation of the tread rubber is proportional to the elastic modulus of the rubber, the deformation is reduced if the tread rubber is hardened. In particular, if the elastic modulus of the tread rubber in the tread center region having a large eccentric effect is increased, the deformation of the tread rubber is reduced. However, when the elastic modulus of the tread rubber in contact with the road surface is simply increased to harden the rubber, deformation of the tread rubber is suppressed, but problems such as the tread pattern block (land portion) being easily peeled off are caused. Therefore, in order to efficiently increase the elastic modulus without incurring these problems, the cap / base structure is applied to the tread, and the thickness of the base rubber layer in the tread center region is reduced compared to the tread shoulder region. did. Hereinafter, the reason will be described.
In the cap / base structure, generally, a high elastic modulus rubber is used for the cap rubber layer to improve durability, and a low elastic modulus rubber is used for the base rubber layer for low heat generation. In the tread center region, if the thickness of the soft base rubber layer having a low elastic modulus is reduced, the tread rubber gauge does not change, so that the thickness of the cap rubber layer having a high elastic modulus is increased. As a result, the elastic modulus of the entire tread rubber including the base rubber layer and the cap rubber layer can be increased in the tread center region. Similarly, in the tread shoulder region, the elastic modulus of the entire tread rubber including the base rubber layer and the cap rubber layer can be reduced by increasing the thickness of the soft base rubber layer having a low elastic modulus.
In this way, in the tread center region where the contact pressure is high, the elastic modulus of the tread rubber is increased to suppress the deformation of the tread rubber, and in the tread shoulder region where the contact pressure is low, the elastic modulus of the tread rubber is decreased. By promoting the deformation of the tread rubber, a distribution in the width direction occurs in the dynamic elastic modulus of the tread. Then, the contact pressure of the tread that is not uniform in the tire width direction is canceled out by the dynamic elastic modulus of the tread that is not uniform in the tire width direction, and the deformation of the tread rubber in the tread width direction is uniformed and the tread is unevenly distributed. Wear is suppressed.

上述したとおり、ベースゴム層６Ｂの厚さが最大となる位置Ｍは、タイヤ赤道面ＣＬを中心に周方向ベルト層３ａ、３ｂの幅の８０％の位置よりタイヤ幅方向外側（トレッドショルダー領域）にあることが肝要である。位置Ｍが、トレッドショルダー領域よりタイヤ幅方向内側に存在する場合、上述した偏摩耗抑制効果が得られない。
さらに、位置Ｍは、周方向ベルト層３ａ、３ｂのタイヤ幅方向端３ａｅ、３ｂｅよりタイヤ幅方向外側にあることが好適である。タイヤ幅方向端３ａｅ、３ｂｅより外側では、周方向ベルト層３ａ、３ｂによるタガ効果は働かず、当該領域の接地圧は急激に低下するため、当該領域に位置Ｍが存在すると、上述した偏摩耗抑制効果が効果的に得られる。 As described above, the position M where the thickness of the base rubber layer 6B is maximum is the outer side in the tire width direction (tread shoulder region) than the position of 80% of the width of the circumferential belt layers 3a and 3b with the tire equatorial plane CL as the center. It is important to be in When the position M exists on the inner side in the tire width direction from the tread shoulder region, the above-described uneven wear suppression effect cannot be obtained.
Further, the position M is preferably located on the outer side in the tire width direction from the tire width direction ends 3ae and 3be of the circumferential belt layers 3a and 3b. Outside the tire width direction ends 3ae and 3be, the tagging effect by the circumferential belt layers 3a and 3b does not work, and the contact pressure in the region decreases rapidly. The suppression effect is obtained effectively.

また、周方向ベルト層３ａ、３ｂのタイヤ幅方向端３ａｅ、３ｂｅにおけるベースゴム層６Ｂの厚さは、好ましくは１ｍｍ〜７ｍｍ、より好ましくは３ｍｍ〜７ｍｍである。
当該厚さが１ｍｍ未満の場合、ベースゴム層６Ｂのが薄すぎて、トレッドゴムにおけるキャップゴム層６Ｃの割合が大きいため、トレッドゴムが十分に変形しないおそれがある。一方、当該厚さが７ｍｍ超の場合、トレッドが摩耗した場合に、ベースゴム層６Ｂが早期に露出するおそれがある。 Further, the thickness of the base rubber layer 6B at the tire width direction ends 3ae and 3be of the circumferential belt layers 3a and 3b is preferably 1 mm to 7 mm, more preferably 3 mm to 7 mm.
When the thickness is less than 1 mm, the base rubber layer 6B is too thin, and the ratio of the cap rubber layer 6C in the tread rubber is large, so that the tread rubber may not be sufficiently deformed. On the other hand, when the thickness exceeds 7 mm, the base rubber layer 6B may be exposed early when the tread is worn.

ベースゴム層６Ｂのトレッドセンター領域における厚さは５ｍｍ以下であることが好適である。当該厚さが５ｍｍ超の場合、トレッドゴムの変形が大きくなり、早期に摩耗が進行するおそれがある。
また、ベースゴム層６Ｂのトレッドセンター領域における厚さと、ベースゴム層６Ｂのトレッドショルダー領域における厚さとの差は３ｍｍ以上であることが好適である。当該差が３ｍｍ未満の場合、トレッドゴムの動的弾性率をタイヤ幅方向に不均一にする効果が十分ではない。なお、当該差の上限は、トレッドゴムのゲージから規定される。 The thickness of the base rubber layer 6B in the tread center region is preferably 5 mm or less. When the thickness is more than 5 mm, the tread rubber is greatly deformed, and there is a risk that the wear proceeds at an early stage.
The difference between the thickness of the base rubber layer 6B in the tread center region and the thickness of the base rubber layer 6B in the tread shoulder region is preferably 3 mm or more. When the difference is less than 3 mm, the effect of making the dynamic elastic modulus of the tread rubber nonuniform in the tire width direction is not sufficient. The upper limit of the difference is defined by a tread rubber gauge.

ベースゴム層６Ｂの厚さが、タイヤ赤道面ＣＬからトレッド接地端Ｅに向かって漸増すること、かつ、キャップゴム層６Ｃとベースゴム層６Ｂとの境界面が、トレッドに配される溝の溝幅の範囲を除き、タイヤ幅方向内側から外側に向かうにつれて、径方向外側に傾斜することが好適である。
トレッド接地端Ｅは、タイヤを正規リムにリム組みし、最大荷重、最大空気圧下（ＪＡＴＭＡ、ＴＲＡ、ＥＴＲＴＯに記載）において算出する。 The thickness of the base rubber layer 6B gradually increases from the tire equatorial plane CL toward the tread grounding end E, and the boundary surface between the cap rubber layer 6C and the base rubber layer 6B is a groove of the groove disposed on the tread. Except for the width range, it is preferable to incline radially outward from the inner side in the tire width direction toward the outer side.
The tread ground contact E is calculated under the maximum load and maximum air pressure (described in JATMA, TRA, and ETRTO) after assembling the tire on a regular rim.

具体的なトレッドゴムの動的弾性率としては、キャップゴム層６Ｃの動的弾性率が８．０ＭＰａ〜２０．０ＭＰａであり、ベースゴム層６Ｂの動的弾性率が１．０ＭＰａ〜７．０ＭＰａであることが好適である。
キャップゴム層６Ｃの動的弾性率が８．０ＭＰａ未満の場合、トレッド６の摩耗を低減する効果が十分でないおそれがあり、一方、キャップゴム層６Ｃの動的弾性率が２０．０ＭＰａ超の場合、グリップ性能が十分でないおそれがある。
ベースゴム層６Ｂの動的弾性率が１．０ＭＰａ未満の場合、操縦安定性能が悪化するおそれがあり、一方、ベースゴム層６Ｂの動的弾性率が７．０ＭＰａ超の場合、ベースゴム層６Ｂの動的弾性率が十分ではなく、トレッドもげ性能に対する寄与が十分でないおそれがある。
なお、動的弾性率（ＭＰａ）は、スペクトロメータで温度２５℃、周波数５２Ｈｚ、歪２％にて測定した。 As the specific dynamic modulus of the tread rubber, the dynamic elastic modulus of the cap rubber layer 6C is 8.0 MPa to 20.0 MPa, and the dynamic elastic modulus of the base rubber layer 6B is 1.0 MPa to 7.0 MPa. It is preferable that
When the dynamic elastic modulus of the cap rubber layer 6C is less than 8.0 MPa, the effect of reducing the wear of the tread 6 may not be sufficient. On the other hand, when the dynamic elastic modulus of the cap rubber layer 6C exceeds 20.0 MPa The grip performance may not be sufficient.
When the dynamic elastic modulus of the base rubber layer 6B is less than 1.0 MPa, the steering stability performance may be deteriorated. On the other hand, when the dynamic elastic modulus of the base rubber layer 6B is more than 7.0 MPa, the base rubber layer 6B There is a possibility that the dynamic elastic modulus is not sufficient and the contribution to the tread baldness performance is not sufficient.
The dynamic elastic modulus (MPa) was measured with a spectrometer at a temperature of 25 ° C., a frequency of 52 Hz, and a strain of 2%.

キャップゴム層６Ｃの動的弾性率が、温度２５℃、周波数５２Ｈｚ、歪２％時において、ベースゴム層６Ｂの動的弾性率の１．５倍以上３．５倍以下であることが好適である。
動的弾性率の比が１．５未満の場合、ゴムの動的弾性率の差が十分ではなく、トレッドゴム全体での動的弾性率変化が不足するおそれがある。一方、動的弾性率の比が３．５超の場合、製造面に困難が生ずるおそれがある。 The dynamic elastic modulus of the cap rubber layer 6C is preferably 1.5 to 3.5 times the dynamic elastic modulus of the base rubber layer 6B at a temperature of 25 ° C., a frequency of 52 Hz, and a strain of 2%. is there.
When the ratio of the dynamic elastic modulus is less than 1.5, the difference in the dynamic elastic modulus of the rubber is not sufficient, and the dynamic elastic modulus change in the entire tread rubber may be insufficient. On the other hand, when the ratio of dynamic elastic moduli is more than 3.5, there is a risk that difficulty in production may occur.

以下、本発明の実施例について説明するが、本発明はこれだけに限定されるものではない。
発明例タイヤ、参考例タイヤ、比較例タイヤおよび従来例タイヤを試作し、トレッドの偏摩耗性能および発熱性能を評価した。
各試作タイヤは、４９５／４５Ｒ２２５のタイヤサイズであり、トレッドには６本の周方向溝が形成されている。また、各試作タイヤは、キャップ／ベース構造であり、キャップゴム層６Ｃの動的弾性率が、ベースゴム層６Ｂの動的弾性率より高い。また、各試作タイヤは、２層の周方向ベルト層および２層の傾斜ベルト層を有し、内側周方向ベルト層幅および外側周方向ベルト層幅は３７０ｍｍ、内側傾斜ベルト層幅は４２０ｍｍ、外側傾斜ベルト層幅は表１に示すとおりである。
従来例タイヤは、図３に示すように、均一厚のベースゴム層６Ｂおよび均一厚のキャップゴム層６Ｃを有する。
発明例タイヤ、参考例タイヤおよび比較例タイヤは、図１に示すように、トレッドセンター領域で薄く、トレッドショルダー領域で厚いベースゴム層６Ｂを有する。
表１に、各試作タイヤのタイヤ赤道面におけるベースゴム層６Ｂの厚さＤｃｌ、周方向ベルト層端におけるベースゴム層６Ｂの厚さＤｓｈと、外側傾斜ベルト層幅と、ベースゴム層６Ｂの厚さが最大となる位置と周方向ベルト層との関係を示す。表１のベースゴム層最大厚位置は、タイヤ赤道面を中心に周方向ベルト層の幅の何％という形で記載している。例えば、「８０％」とは、ベースゴム層６Ｂの厚さが最大となる位置がタイヤ赤道面を中心に周方向ベルト層の幅の８０％の位置上にあることを示している。 Examples of the present invention will be described below, but the present invention is not limited thereto.
Invention example tires, reference example tires, comparative example tires and conventional example tires were prototyped, and the uneven wear performance and heat generation performance of the tread were evaluated.
Each prototype tire has a tire size of 495 / 45R225, and six circumferential grooves are formed in the tread. Each prototype tire has a cap / base structure, and the dynamic elastic modulus of the cap rubber layer 6C is higher than the dynamic elastic modulus of the base rubber layer 6B. Each prototype tire has two circumferential belt layers and two inclined belt layers, the inner circumferential belt layer width and the outer circumferential belt layer width are 370 mm, the inner inclined belt layer width is 420 mm, and the outer The inclined belt layer width is as shown in Table 1.
As shown in FIG. 3, the conventional tire includes a base rubber layer 6B having a uniform thickness and a cap rubber layer 6C having a uniform thickness.
The invention example tire, the reference example tire, and the comparative example tire have a base rubber layer 6B that is thin in the tread center region and thick in the tread shoulder region, as shown in FIG.
Table 1 shows the thickness Dcl of the base rubber layer 6B at the tire equatorial plane of each prototype tire, the thickness Dsh of the base rubber layer 6B at the end of the circumferential belt layer, the outer inclined belt layer width, and the thickness of the base rubber layer 6B. The relationship between the position where the height is the maximum and the circumferential belt layer is shown. The base rubber layer maximum thickness position in Table 1 is described as a percentage of the width of the circumferential belt layer centering on the tire equatorial plane. For example, “80%” indicates that the position where the thickness of the base rubber layer 6B is maximum is on the position of 80% of the width of the circumferential belt layer with the tire equatorial plane as the center.

（偏摩耗性能の測定）
以下の（１）（２）の方法に従って、偏摩耗性能を測定した。
（１）各試作タイヤを１７．００インチ幅の適用リムに組み付けてタイヤ車輪とし、内圧９００ｋｐａで、トラクターヘッドのドライブ軸に装着し、定積載のトレーラーを引いて５００００ｋｍ走行したときの、タイヤ赤道面ＣＬに最も近い周方向溝の深さ（ＣＬ摩耗溝深さ）およびトレッド接地端Ｅに最も近い周方向溝の深さ（ＳＨ摩耗溝深さ）を測定した。測定結果（摩耗した溝深さ）は、（新品時の溝深さ−走行後の溝深さ）として表１に示す。
（２）各試作タイヤを１７．００インチ幅の適用リムに組み付けてタイヤ車輪とし、内圧９００ｋｐａで、トラクターヘッドのドライブ軸に装着し、空積載のトレーラーを引いて５００００ｋｍ走行したときの、トレッド接地端Ｅの摩耗体積を測定した。結果は、従来例タイヤ１の摩耗体積を１００として指数表示した。なお、指数が小さいほど、性能に優れていることを示す。 (Measurement of uneven wear performance)
The uneven wear performance was measured according to the following methods (1) and (2).
(1) The tire equator when each prototype tire is assembled to a 17.00 inch wide applicable rim to form a tire wheel, mounted on the drive shaft of the tractor head with an internal pressure of 900 kpa, and a fixed load trailer is pulled and traveled 50000 km The depth of the circumferential groove closest to the surface CL (CL wear groove depth) and the depth of the circumferential groove closest to the tread ground end E (SH wear groove depth) were measured. The measurement results (worn groove depth) are shown in Table 1 as (groove depth at new article−groove depth after running).
(2) Tread grounding when each prototype tire is assembled to a 17.00 inch wide applicable rim to form a tire wheel, mounted on the drive shaft of the tractor head with an internal pressure of 900 kpa, and pulled on an empty trailer for 50000 km The wear volume at end E was measured. The results are shown as indexes with the wear volume of the conventional tire 1 as 100. In addition, it shows that it is excellent in performance, so that an index | exponent is small.

なお、適用リムとは、ＪＡＴＭＡに規定される「適用リム」、ＴＲＡに規定される「Ｄｅｓｉｇｎ Ｒｉｍ」、あるいはＥＴＲＴＯに規定される「Ｍｅａｓｕｒｉｎｇ Ｒｉｍ」をいう。   The applied rim means an “applied rim” defined in JATMA, a “Design Rim” defined in TRA, or a “Measuring Rim” defined in ETRTO.

（発熱性能の測定）
上記偏摩耗性能の測定（１）における走行後、トレッドショルダー領域２箇所における外側傾斜ベルト層上のベースゴム層の温度を測定した。結果は、従来例タイヤ１の平均温度を１００として指数表示した。なお、指数が小さいほど、性能に優れていることを示す。 (Measurement of heat generation performance)
After running in the measurement (1) of the uneven wear performance, the temperature of the base rubber layer on the outer inclined belt layer in the two tread shoulder regions was measured. The results are shown as an index with the average temperature of the conventional tire 1 as 100. In addition, it shows that it is excellent in performance, so that an index | exponent is small.

Figure 2016104626
Figure 2016104626

表１より、発明例タイヤは、発熱性能を維持したまま偏摩耗性能を大きく向上していることが分かる。   From Table 1, it can be seen that the invention example tires greatly improve the uneven wear performance while maintaining the heat generation performance.

２ カーカス
３ａ 周方向ベルト層
３ｂ 周方向ベルト層
４ａ 傾斜ベルト層
４ｂ 傾斜ベルト層
６ トレッド
６Ｃ キャップゴム層
６Ｂ ベースゴム層
１０ 空気入りタイヤ 2 carcass 3a circumferential belt layer 3b circumferential belt layer 4a inclined belt layer 4b inclined belt layer 6 tread 6C cap rubber layer 6B base rubber layer 10 pneumatic tire

Claims (4)

１対のビードコア間でトロイド状に延びるカーカスを骨格とし、このカーカスのタイヤ径方向外側に、少なくとも１層の周方向ベルト層およびトレッドを具えるタイヤにおいて、
前記トレッドを複数のトレッドゴム層から形成し、
タイヤ径方向最外側に位置する外側トレッドゴム層の動的弾性率が、タイヤ径方向最内側に位置する内側トレッドゴム層の動的弾性率より高く、
トレッドセンター領域における前記内側トレッドゴム層の厚さが、前記周方向ベルト層のタイヤ幅方向端部領域における前記内側トレッドゴム層の厚さよりも薄く、
前記内側トレッドゴム層は、タイヤ赤道面を横断してタイヤ幅方向両側に亘って延在し、当該内側トレッドゴム層の厚さが最大となる位置は、タイヤ赤道面を中心に前記周方向ベルト層の幅の８０％の位置よりタイヤ幅方向外側にあり、
スペクトロメータで温度２５℃、周波数５２Ｈｚ、歪２％にて測定した、前記外側トレッドゴム層の動的弾性率が、８．０ＭＰａ〜２０ＭＰａであり、
スペクトロメータで温度２５℃、周波数５２Ｈｚ、歪２％にて測定した、前記内側トレッドゴム層の動的弾性率が１．０ＭＰａ〜７．０ＭＰａであり、
前記外側トレッドゴム層の動的弾性率が、温度２５℃、周波数５２Ｈｚ、歪２％時において、前記内側トレッドゴム層の動的弾性率の１．５倍以上３．５倍以下であり、
前記少なくとも１層の周方向ベルト層は、タイヤ赤道面を横断してタイヤ幅方向両側に連続的に延在するとともに前記カーカスのタイヤ径方向外側に隣接して位置することを特徴とする重荷重用空気入りタイヤ。 In a tire having a carcass extending in a toroidal shape between a pair of bead cores and having at least one circumferential belt layer and a tread on the outer side in the tire radial direction of the carcass,
Forming the tread from a plurality of tread rubber layers;
The dynamic elastic modulus of the outer tread rubber layer located on the outermost side in the tire radial direction is higher than the dynamic elastic modulus of the inner tread rubber layer located on the innermost side in the tire radial direction,
The thickness of the inner tread rubber layer in the tread center region is thinner than the thickness of the inner tread rubber layer in the tire width direction end region of the circumferential belt layer,
The inner tread rubber layer extends across the tire equatorial plane and on both sides in the tire width direction, and the position where the thickness of the inner tread rubber layer is maximum is centered on the tire equatorial plane. It is on the outside in the tire width direction from the position of 80% of the width of the layer,
The dynamic elastic modulus of the outer tread rubber layer measured at a temperature of 25 ° C., a frequency of 52 Hz, and a strain of 2% with a spectrometer is 8.0 MPa to 20 MPa,
The dynamic elastic modulus of the inner tread rubber layer measured by a spectrometer at a temperature of 25 ° C., a frequency of 52 Hz and a strain of 2% is 1.0 MPa to 7.0 MPa,
The dynamic elastic modulus of the outer tread rubber layer is 1.5 times to 3.5 times the dynamic elastic modulus of the inner tread rubber layer at a temperature of 25 ° C., a frequency of 52 Hz, and a strain of 2%.
The at least one circumferential belt layer extends continuously on both sides in the tire width direction across the tire equatorial plane and is located adjacent to the outer side in the tire radial direction of the carcass. Pneumatic tire. 前記内側トレッドゴム層の厚さが、タイヤ赤道面からトレッド接地端に向かって漸増することを特徴とする請求項１に記載の重荷重用空気入りタイヤ。   2. The heavy duty pneumatic tire according to claim 1, wherein a thickness of the inner tread rubber layer gradually increases from a tire equatorial plane toward a tread ground contact end. 前記内側トレッドゴム層の厚さが最大となる位置は、前記周方向ベルト層のタイヤ幅方向端よりタイヤ幅方向外側にあることを特徴とする請求項１または２に記載の重荷重用空気入りタイヤ。   3. The heavy duty pneumatic tire according to claim 1, wherein the position where the thickness of the inner tread rubber layer is maximum is located on the outer side in the tire width direction from the end in the tire width direction of the circumferential belt layer. . 前記内側トレッドゴム層の厚さが増加開始する位置は、前記周方向ベルト層の幅の４０％よりタイヤ幅方向外側にあることを特徴とする請求項１〜３のいずれかに記載の重荷重用空気入りタイヤ。   The heavy load load according to any one of claims 1 to 3, wherein a position where the thickness of the inner tread rubber layer starts to increase is located on the outer side in the tire width direction from 40% of the width of the circumferential belt layer. Pneumatic tire.
JP2016017395A 2016-02-01 2016-02-01 Pneumatic tire Expired - Fee Related JP6033975B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2016017395A JP6033975B2 (en) 2016-02-01 2016-02-01 Pneumatic tire

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2016017395A JP6033975B2 (en) 2016-02-01 2016-02-01 Pneumatic tire

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
JP2010167956A Division JP5933911B2 (en) 2010-07-27 2010-07-27 Pneumatic tire

Publications (2)

Publication Number Publication Date
JP2016104626A true JP2016104626A (en) 2016-06-09
JP6033975B2 JP6033975B2 (en) 2016-11-30

Family

ID=56102654

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2016017395A Expired - Fee Related JP6033975B2 (en) 2016-02-01 2016-02-01 Pneumatic tire

Country Status (1)

Country Link
JP (1) JP6033975B2 (en)

Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61229602A (en) * 1985-04-04 1986-10-13 Ohtsu Tire & Rubber Co Ltd Automobile tire tread
JPH04278807A (en) * 1991-03-04 1992-10-05 Toyo Tire & Rubber Co Ltd Pneumatic tire
JPH06157829A (en) * 1992-11-20 1994-06-07 Toyo Tire & Rubber Co Ltd Pneumatic radial tire for truck and bus
JP2000016020A (en) * 1998-07-01 2000-01-18 Yokohama Rubber Co Ltd:The Heavy duty pneumatic radial tire
JP2001071708A (en) * 1999-09-02 2001-03-21 Bridgestone Corp Pneumatic tire
JP2001191732A (en) * 1999-12-29 2001-07-17 Sumitomo Rubber Ind Ltd Pneumatic tire
JP2003127613A (en) * 2001-10-25 2003-05-08 Sumitomo Rubber Ind Ltd Heavy load radial tire
JP2004083001A (en) * 2002-06-28 2004-03-18 Bridgestone Corp Pneumatic radial tire
JP2005015691A (en) * 2003-06-27 2005-01-20 Bridgestone Corp Tire
JP2005035404A (en) * 2003-07-15 2005-02-10 Sumitomo Rubber Ind Ltd Pneumatic tire for heavy load
JP2005125893A (en) * 2003-10-22 2005-05-19 Sumitomo Rubber Ind Ltd Heavy duty radial-ply tire
JP2007137411A (en) * 2005-10-17 2007-06-07 Sumitomo Rubber Ind Ltd Tire for heavy load
JP2007137134A (en) * 2005-11-15 2007-06-07 Bridgestone Corp Pneumatic tire
JP2007137384A (en) * 2005-11-22 2007-06-07 Sumitomo Rubber Ind Ltd Radial tire for heavy load
JP2007176438A (en) * 2005-12-28 2007-07-12 Sumitomo Rubber Ind Ltd Heavy duty radial tire
JP2008013609A (en) * 2006-07-03 2008-01-24 Toyo Tire & Rubber Co Ltd Rubber composition for base tread of heavy load tire

Patent Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61229602A (en) * 1985-04-04 1986-10-13 Ohtsu Tire & Rubber Co Ltd Automobile tire tread
JPH04278807A (en) * 1991-03-04 1992-10-05 Toyo Tire & Rubber Co Ltd Pneumatic tire
JPH06157829A (en) * 1992-11-20 1994-06-07 Toyo Tire & Rubber Co Ltd Pneumatic radial tire for truck and bus
JP2000016020A (en) * 1998-07-01 2000-01-18 Yokohama Rubber Co Ltd:The Heavy duty pneumatic radial tire
JP2001071708A (en) * 1999-09-02 2001-03-21 Bridgestone Corp Pneumatic tire
JP2001191732A (en) * 1999-12-29 2001-07-17 Sumitomo Rubber Ind Ltd Pneumatic tire
JP2003127613A (en) * 2001-10-25 2003-05-08 Sumitomo Rubber Ind Ltd Heavy load radial tire
JP2004083001A (en) * 2002-06-28 2004-03-18 Bridgestone Corp Pneumatic radial tire
JP2005015691A (en) * 2003-06-27 2005-01-20 Bridgestone Corp Tire
JP2005035404A (en) * 2003-07-15 2005-02-10 Sumitomo Rubber Ind Ltd Pneumatic tire for heavy load
JP2005125893A (en) * 2003-10-22 2005-05-19 Sumitomo Rubber Ind Ltd Heavy duty radial-ply tire
JP2007137411A (en) * 2005-10-17 2007-06-07 Sumitomo Rubber Ind Ltd Tire for heavy load
JP2007137134A (en) * 2005-11-15 2007-06-07 Bridgestone Corp Pneumatic tire
JP2007137384A (en) * 2005-11-22 2007-06-07 Sumitomo Rubber Ind Ltd Radial tire for heavy load
JP2007176438A (en) * 2005-12-28 2007-07-12 Sumitomo Rubber Ind Ltd Heavy duty radial tire
JP2008013609A (en) * 2006-07-03 2008-01-24 Toyo Tire & Rubber Co Ltd Rubber composition for base tread of heavy load tire

Also Published As

Publication number Publication date
JP6033975B2 (en) 2016-11-30

Similar Documents

Publication Publication Date Title
JP6186147B2 (en) Pneumatic tire
JP5436439B2 (en) tire
WO2014162732A1 (en) Pneumatic tire
JP5519167B2 (en) Pneumatic tire
JP2011183994A (en) Pneumatic tire
JPWO2010087190A1 (en) Pneumatic tire
JP2011057183A (en) Pneumatic tire
JP6033975B2 (en) Pneumatic tire
US20230271452A1 (en) Tire
JP2017030506A (en) Tire for two-wheeled motor vehicle
JP5933911B2 (en) Pneumatic tire
JP7275464B2 (en) pneumatic tire
JP6245003B2 (en) Pneumatic tire
JP6450111B2 (en) Pneumatic tire
JP2018090078A (en) Pneumatic tire
JP5829384B2 (en) Pneumatic tire
US20190135040A1 (en) Pneumatic tire
JP5623864B2 (en) Pneumatic tire
JP2021079872A (en) Pneumatic tire for heavy load
JP2016112980A (en) Pneumatic tire
JP2012180064A (en) Pneumatic tire
JP2014076765A (en) Retreaded tire
JP2013079018A (en) Pneumatic tire
JP5275655B2 (en) Pneumatic tire
JP2016030452A (en) Tire for motorcycle

Legal Events

Date Code Title Description
TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20161004

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20161026

R150 Certificate of patent or registration of utility model

Ref document number: 6033975

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

LAPS Cancellation because of no payment of annual fees