JP2010030054A

JP2010030054A - Method of manufacturing pneumatic tire

Info

Publication number: JP2010030054A
Application number: JP2008191765A
Authority: JP
Inventors: Tsutomu Nomaguchi; 強野間口
Original assignee: Yokohama Rubber Co Ltd
Current assignee: Yokohama Rubber Co Ltd
Priority date: 2008-07-25
Filing date: 2008-07-25
Publication date: 2010-02-12

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a pneumatic tire in which deterioration of physical properties of a tread is suppressed while an efficiency of a vulcanization cycle in the tire, in which two or more different kinds of rubber compositions different in vulcanization rate are arranged in the tread, is increased. <P>SOLUTION: In the method of manufacturing the pneumatic tire, when the pneumatic tire 1 in which two or more kinds of rubber compositions 2a and 2b different in vulcanization rate are arranged in a width direction of a tread 2 is vulcanization molded, after the tire is vulcanized with a vulcanizer for a vulcanizing time determined with reference to the fastest vulcanization rate of a rubber composition among the rubber compositions 2a and 2b, or for a time shorter than thereof, the tire is taken out from a vulcanization mold, and additional vulcanization is carried out by heating the tread 2 from a surface side of the tread according to the vulcanization rate of rubber compositions 2a and 2b until the rubber compositions 2a and 2b arranged in the tread 2 are subjected in proper vulcanization, respectively. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

本発明は空気入りタイヤの製造方法に関し、さらに詳しくは、トレッド部に複数の異なるゴム組成物を配置したタイヤにおける加硫サイクルの効率化を図りながら、トレッド物性の低下を抑制するようにした空気入りタイヤの製造方法に関する。 The present invention relates to a method for manufacturing a pneumatic tire. More specifically, the present invention relates to an air in which deterioration of physical properties of a tread is suppressed while improving efficiency of a vulcanization cycle in a tire in which a plurality of different rubber compositions are arranged in a tread portion. The present invention relates to a method for manufacturing a tire.

近年の車両の高性能化を受けてタイヤへの要求特性もますます多岐にわたり、トレッド部の幅方向に複数の異なる物性からなるゴム組成物を配置して、車両への装着位置を指定することにより、これらの要求特性に応えるようにしたタイヤが広く上市されるようになってきた（例えば、特許文献１参照）。 With the increasing performance of vehicles in recent years, the required characteristics of tires are becoming more and more diverse, and a rubber composition consisting of multiple different physical properties is placed in the width direction of the tread part to specify the mounting position on the vehicle Accordingly, tires that meet these required characteristics have been widely marketed (see, for example, Patent Document 1).

一般に、物性の異なるゴム組成物は互いに加硫速度が異なるため、物性の異なるゴム組成物をトレッド部に配置したタイヤでは、通例、加硫速度の遅いゴム組成物を基準にして加硫時間が設定されている。そのため、加硫速度の速いゴム組成物は過加硫にならざるを得ず、これに伴い所望のトレッド物性が得られないという問題があった。 In general, rubber compositions having different physical properties have different vulcanization speeds. Therefore, in a tire in which rubber compositions having different physical properties are arranged in the tread portion, the vulcanization time is usually based on a rubber composition having a low vulcanization speed. Is set. For this reason, a rubber composition having a high vulcanization rate must be overvulcanized, and accordingly, there has been a problem that desired tread physical properties cannot be obtained.

従来、トレッド部を単一のゴム組成物で構成したタイヤにおけるトレッドゴムの過加硫を防止する対策として、加硫後のタイヤにおけるトレッド部の表面温度を測定し、この測定値に応じてトレッド面に冷却媒体などを選択的に噴射するようにした提案がある（例えば、特許文献２参照）。しかし、これらの提案は、加硫後のタイヤにおける加硫の進行を制御するには有効であるものの、一旦加硫機の中で過加硫状態に加硫されたゴム組成物は適正な加硫状態に戻すことができないので、過加硫防止対策としては未だ充分なものとはなり得なかった。
特開２００３−３２６９１７号公報特開２００８−２３８２８号公報 Conventionally, as a measure to prevent over-vulcanization of the tread rubber in a tire in which the tread portion is composed of a single rubber composition, the surface temperature of the tread portion in the tire after vulcanization is measured, and the tread is determined according to the measured value. There is a proposal of selectively injecting a cooling medium or the like on the surface (see, for example, Patent Document 2). However, although these proposals are effective for controlling the progress of vulcanization in a tire after vulcanization, a rubber composition once vulcanized in an overvulcanized state in a vulcanizer is not properly vulcanized. Since it cannot be returned to the vulcanized state, it has not yet been sufficient as a measure for preventing overvulcanization.
JP 2003-326917 A JP 2008-23828 A

本発明の目的は、かかる従来の問題点を解消するもので、トレッド部に加硫速度の異なる複数種類の異なるゴム組成物を配置したタイヤにおける加硫サイクルの効率化を図りながら、トレッド物性の低下を抑制するようにした空気入りタイヤの製造方法を提供することにある。 An object of the present invention is to solve such a conventional problem, and to improve the efficiency of a vulcanization cycle in a tire in which a plurality of different rubber compositions having different vulcanization speeds are arranged in a tread portion, It is in providing the manufacturing method of the pneumatic tire which suppressed the fall.

上記目的を達成するための本発明の空気入りタイヤの製造方法は、トレッド部の幅方向に加硫速度の異なる複数種類のゴム組成物を配置した空気入りタイヤを加硫成形するに際して、前記ゴム組成物のうち加硫速度が最も速いゴム組成物を基準にして定められた加硫時間又はそれより短い時間にわたり、加硫機によりタイヤの加硫を行った後、該タイヤを加硫金型から取り出して、前記トレッド部に配置された複数種類のゴム組成物がそれぞれ適正加硫に至るまで、前記トレッド部を前記ゴム組成物の加硫速度に応じてトレッド表面側から加熱することにより追加加硫を施すようにしたことを特徴にする。 In order to achieve the above object, the method for producing a pneumatic tire according to the present invention includes the step of vulcanizing and molding a pneumatic tire in which a plurality of types of rubber compositions having different vulcanization speeds are arranged in the width direction of the tread portion. The tire is vulcanized by a vulcanizer for a vulcanization time determined based on the rubber composition having the fastest vulcanization speed among the compositions or for a shorter time, and then the tire is vulcanized. It is added by heating the tread part from the tread surface side according to the vulcanization speed of the rubber composition until each of the plurality of types of rubber compositions arranged in the tread part reaches proper vulcanization. It is characterized by vulcanization.

さらに、上述する構成において、以下の（１）及び／又は（２）に記載するように構成することが好ましい。 Furthermore, in the above-described configuration, it is preferable to configure as described in the following (1) and / or (2).

（１）前記追加加硫において、各ゴム組成物の表面温度が前記加硫機における金型温度Ｔ（℃）に対して以下の関係になるようにする。
Ｔａ≧Ｔｘ≧Ｔｂ
Ｔ≧Ｔａ≧Ｔ−５０℃
Ｔ≧Ｔｂ≧Ｔ−１５０℃
ただし、Ｔａは加硫速度が最も遅いゴム組成物の表面温度、Ｔｂは加硫速度が最も速いゴム組成物の表面温度、Ｔｘは加硫速度が中間であるゴム組成物の表面温度を示す。
（２）前記追加加硫における加熱をガスの噴き付け、赤外線の照射又は発熱体の接触により行う。 (1) In the additional vulcanization, the surface temperature of each rubber composition is set to have the following relationship with the mold temperature T (° C.) in the vulcanizer.
Ta ≧ Tx ≧ Tb
T ≧ Ta ≧ T−50 ° C
T ≧ Tb ≧ T−150 ° C.
However, Ta represents the surface temperature of the rubber composition having the slowest vulcanization rate, Tb represents the surface temperature of the rubber composition having the fastest vulcanization rate, and Tx represents the surface temperature of the rubber composition having an intermediate vulcanization rate.
(2) The heating in the additional vulcanization is performed by spraying gas, irradiating with infrared rays, or contacting a heating element.

本発明によれば、トレッド部に配置された加硫速度の異なる複数種類のゴム組成物のうち加硫速度が最も速いゴム組成物を基準にして定められた加硫時間又はそれより短い時間にわたり、加硫機によりタイヤの加硫を行った後、そのタイヤを加硫金型から取り出して、トレッド部に配置された複数種類のゴム組成物がそれぞれ適正加硫に至るまで、トレッド部を各ゴム組成物の加硫速度に応じてトレッド表面側から加熱することにより追加加硫を施すようにしたので、加硫後のタイヤにおける各ゴム組成物は未加硫状態であったり過加硫状態であったりすることなく、適正な加硫状態になっているため、トレッド物性の低下を抑制することができる。 According to the present invention, the vulcanization time determined on the basis of the rubber composition having the fastest vulcanization speed among a plurality of types of rubber compositions having different vulcanization speeds arranged in the tread portion or over a shorter time. After the tire is vulcanized with a vulcanizer, the tire is taken out of the vulcanization mold, and each of the tread parts is placed in the tread part until each of the rubber compositions arranged in the tread part is properly vulcanized. Since additional vulcanization is performed by heating from the tread surface side according to the vulcanization speed of the rubber composition, each rubber composition in the tire after vulcanization is in an unvulcanized state or an overvulcanized state. Since it is in an appropriate vulcanized state without being, it is possible to suppress a decrease in physical properties of the tread.

しかも、追加加硫工程が付加されるものの、加硫機における加硫時間が短縮されるため、加硫機の稼動効率の向上により加硫サイクルの効率化を図ることができる。 In addition, although an additional vulcanization step is added, since the vulcanization time in the vulcanizer is shortened, the efficiency of the vulcanization cycle can be improved by improving the operation efficiency of the vulcanizer.

本発明の実施形態について添付の図面を参照して詳細に説明する。 Embodiments of the present invention will be described in detail with reference to the accompanying drawings.

図１は、本発明の実施形態による空気入りタイヤの製造方法により加硫成形された空気入りタイヤの一例を示す断面図である。 FIG. 1 is a cross-sectional view showing an example of a pneumatic tire vulcanized by the method for manufacturing a pneumatic tire according to an embodiment of the present invention.

図１において、空気入りタイヤ１のトレッド部２の幅方向には、加硫速度の異なる複数種類（図では２種類）のゴム組成物２ａ、２ｂが配置されている。なお、図中３はベルト層を、４はカーカス層をそれぞれ示している。 In FIG. 1, a plurality of types (two types in the figure) of rubber compositions 2 a and 2 b having different vulcanization speeds are arranged in the width direction of the tread portion 2 of the pneumatic tire 1. In the figure, 3 indicates a belt layer and 4 indicates a carcass layer.

そして、本発明の空気入りタイヤ１の製造方法では、空気入りタイヤ１を加硫成形するに際して、ゴム組成物２ａ、２ｂのうち加硫速度が最も速いゴム組成物を基準にして定められた加硫時間又はそれより短い時間にわたり、加硫機によりタイヤの加硫を行った後、タイヤを加硫金型から取り出して、トレッド部２に配置された複数種類のゴム組成物２ａ、２ｂがそれぞれ適正加硫に至るまで、トレッド部２を各ゴム組成物２ａ、２ｂの加硫速度に応じてトレッド表面側から加熱することにより追加加硫を施すようにしている。 And in the manufacturing method of the pneumatic tire 1 of the present invention, when the pneumatic tire 1 is vulcanized, the vulcanization determined based on the rubber composition having the fastest vulcanization speed among the rubber compositions 2a and 2b. After vulcanizing the tire with a vulcanizer for a vulcanization time or shorter, the tire is taken out of the vulcanization mold, and a plurality of types of rubber compositions 2a and 2b arranged in the tread portion 2 are respectively Until the proper vulcanization is achieved, additional vulcanization is performed by heating the tread portion 2 from the tread surface side in accordance with the vulcanization speed of each rubber composition 2a, 2b.

これにより、加硫後のタイヤのトレッド部２における各ゴム組成物２ａ、２ｂが未加硫状態であったり過加硫状態であったりすることなく、適正な加硫状態になっているため、トレッド物性の低下を抑制することができる。しかも、追加加硫工程が付加されるものの、加硫機における加硫時間が短縮されるため、加硫機の稼動効率の向上により加硫サイクルの効率化を図ることができる。 Thereby, since each rubber composition 2a, 2b in the tread portion 2 of the vulcanized tire is in an appropriate vulcanized state without being in an unvulcanized state or in an overvulcanized state, A decrease in tread physical properties can be suppressed. In addition, although an additional vulcanization step is added, since the vulcanization time in the vulcanizer is shortened, the efficiency of the vulcanization cycle can be improved by improving the operation efficiency of the vulcanizer.

本発明において、上述する追加加硫工程では、各ゴム組成物の表面温度が加硫機における金型温度Ｔ（℃）に対して以下の関係になるように調整することが好ましい。
Ｔａ≧Ｔｘ≧Ｔｂ
Ｔ≧Ｔａ≧Ｔ−５０℃
Ｔ≧Ｔｂ≧Ｔ−１５０℃
ただし、Ｔａは加硫速度が最も遅いゴム組成物の表面温度、Ｔｂは加硫速度が最も速いゴム組成物の表面温度、Ｔｘは加硫速度が中間であるゴム組成物の表面温度を示す。 In the present invention, in the additional vulcanization step described above, it is preferable to adjust the surface temperature of each rubber composition so as to have the following relationship with the mold temperature T (° C.) in the vulcanizer.
Ta ≧ Tx ≧ Tb
T ≧ Ta ≧ T−50 ° C
T ≧ Tb ≧ T−150 ° C.
However, Ta represents the surface temperature of the rubber composition having the slowest vulcanization rate, Tb represents the surface temperature of the rubber composition having the fastest vulcanization rate, and Tx represents the surface temperature of the rubber composition having an intermediate vulcanization rate.

これにより、追加加硫工程において各ゴム組成物の加硫度を短時間で最適化させることができ、加硫サイクルを一層効率化することができる。ここで、Ｔａが「金型温度Ｔ（℃）−５０℃」を下回ったり、Ｔｂが「金型温度Ｔ（℃）−１５０℃」を下回ったりすると、短時間で効率的に加硫度を増加させることが困難になる。 Thereby, the vulcanization degree of each rubber composition can be optimized in a short time in the additional vulcanization step, and the vulcanization cycle can be made more efficient. Here, if Ta is lower than “mold temperature T (° C.) − 50 ° C.” or Tb is lower than “mold temperature T (° C.) — 150 ° C.”, the vulcanization degree can be efficiently reduced in a short time. It becomes difficult to increase.

上述する追加加硫工程における加熱方法は、特に限定されるものではないが、ガスの噴き付け、赤外線の照射又は発熱体の接触により行うとよい。いずれの場合にあっても、この追加加硫工程では、空気入りタイヤ１のトレッド部２をトレッド表面側から加熱することにより行われる。 The heating method in the additional vulcanization step described above is not particularly limited, and may be performed by gas spraying, infrared irradiation, or heating element contact. In any case, this additional vulcanization step is performed by heating the tread portion 2 of the pneumatic tire 1 from the tread surface side.

ここで、ガスの噴き付けにより加熱する場合には、温度調整を行った高温ガスをタイヤのトレッド表面に直接噴き付けることによって行うとよい。ガスの種類は特に限定されるものではないが、例えば、加熱された空気を使用することができる。ガスの噴き付けは、環状のトレッド表面を取り囲むように配置された複数のノズルから行ってもよく、又は、タイヤ周上の１箇所に配置されたノズルからガスを噴射しながらタイヤを回転させてもよい。 Here, in the case of heating by gas spraying, it is preferable that the temperature-adjusted high-temperature gas is sprayed directly on the tread surface of the tire. Although the kind of gas is not specifically limited, For example, the heated air can be used. Gas injection may be performed from a plurality of nozzles arranged so as to surround the annular tread surface, or the tire is rotated while jetting gas from nozzles arranged at one place on the tire circumference. Also good.

この場合には、隣接するゴム組成物２ａ、２ｂの境界に遮蔽板などを配置しておき、ゴム組成物２ａ、２ｂの加熱をそれぞれ別個のガス供給手段から噴き付けられた高温ガスにより並行させて行うとよい。 In this case, a shielding plate or the like is disposed at the boundary between the adjacent rubber compositions 2a and 2b, and the heating of the rubber compositions 2a and 2b is performed in parallel by high-temperature gas sprayed from separate gas supply means. It is good to do.

また、赤外線の照射により加熱する場合には、赤外線の強度を調整しながらトレッド表面に照射することによって行うとよい。赤外線の照射は、環状のトレッド表面を取り囲むように配置された赤外線の照射装置から行うとよい。この場合においても、隣接するゴム組成物２ａ、２ｂの境界に遮蔽板などを配置しておき、ゴム組成物２ａ、２ｂの加熱をそれぞれ別個の照射装置から照射された赤外線により並行させて行うとよい。 Moreover, when heating by infrared irradiation, it is good to carry out by irradiating the tread surface while adjusting the intensity of infrared rays. The infrared irradiation may be performed from an infrared irradiation device arranged so as to surround the annular tread surface. Even in this case, when a shielding plate or the like is arranged at the boundary between the adjacent rubber compositions 2a and 2b, and the heating of the rubber compositions 2a and 2b is performed in parallel by infrared rays irradiated from separate irradiation devices, respectively. Good.

さらに、発熱体の接触により加熱する場合には、温度を調整した発熱体をトレッド表面に対して直接接触させて行うとよい。この場合には、環状の発熱体をトレッド表面を取り囲むように配置して行うとよい。 Further, in the case of heating by contact with the heating element, the heating element whose temperature is adjusted may be directly brought into contact with the tread surface. In this case, an annular heating element may be arranged so as to surround the tread surface.

なお、上述する追加加硫では、トレッド部２に配置されたゴム組成物２ａ、２ｂの種類によっては、ゴム組成物２ａとゴム組成物２ｂとをそれぞれ異なる加熱方法によって加熱することができる。 In the additional vulcanization described above, the rubber composition 2a and the rubber composition 2b can be heated by different heating methods depending on the types of the rubber compositions 2a and 2b arranged in the tread portion 2.

上述するように、本発明の空気入りタイヤの製造方法は、トレッド部に配置された加硫速度の異なる複数種類のゴム組成物のうち加硫速度が最も速いゴム組成物を基準にして定められた加硫時間又はそれより短い時間にわたり、加硫機によりタイヤの加硫を行った後、そのタイヤを加硫金型から取り出して、トレッド部に配置された各ゴム組成物がそれぞれ適正加硫に至るまで、トレッド部を各ゴム組成物の加硫速度に応じてトレッド表面側から加熱することにより追加加硫を施すことにより、加硫機における加硫時間を短縮して、加硫サイクルの効率化を図りながら、トレッド物性の低下を抑制するようにしたもので、複数種類のゴム組成物をトレッド部に配置した高性能タイヤの製造方法として幅広く適用することができる。 As described above, the pneumatic tire manufacturing method of the present invention is determined based on the rubber composition having the fastest vulcanization speed among a plurality of types of rubber compositions having different vulcanization speeds arranged in the tread portion. After the tire is vulcanized with a vulcanizer for a vulcanization time or shorter, the tire is removed from the vulcanization mold, and each rubber composition placed in the tread portion is properly vulcanized. Until the tread part is heated from the tread surface side according to the vulcanization speed of each rubber composition, by performing additional vulcanization, the vulcanization time in the vulcanizer is shortened, and the vulcanization cycle is reduced. It is intended to suppress the deterioration of physical properties of the tread while improving efficiency, and can be widely applied as a method for producing a high-performance tire in which a plurality of types of rubber compositions are arranged in the tread portion.

タイヤサイズを２５５／４０Ｒ１８、トレッド部におけるゴム組成物の配置形態を図１として、トレッド部に１６０℃における９５％加硫時間Ｔ９５が２５分のゴム組成物２ａと、Ｔ９５が７分のゴム組成物２ｂとをそれぞれ配置して未加硫タイヤを作製した。 The tire size is 255 / 40R18, the arrangement of the rubber composition in the tread part is shown in FIG. 1, the rubber composition 2a having a 95% vulcanization time T95 at 160 ° C. of 25 minutes and the rubber composition of T95 being 7 minutes in the tread part. An unvulcanized tire was prepared by arranging the product 2b.

これら未加硫タイヤをそれぞれ以下（１）〜（４）に記載する加硫方式により加硫成形し、加硫後のタイヤにおけるトレッド部からゴム組成物２ａ、２ｂを採取して、２３℃におけるＪＩＳ硬さ（Ａタイプ）及び３００％伸長時における引張応力（３００％モジュラス）をそれぞれ測定し、その結果を（１）の加硫方式により得られた値を１００とする指数により表１に記載した。 These unvulcanized tires were respectively vulcanized and molded by the vulcanization method described in (1) to (4) below, and rubber compositions 2a and 2b were collected from the tread portions of the vulcanized tires at 23 ° C. JIS hardness (A type) and tensile stress (300% modulus) at 300% elongation were measured, respectively, and the results are shown in Table 1 as an index with the value obtained by the vulcanization method of (1) as 100. did.

（１）加硫機において金型温度を１８０℃として１２分間加硫し、これを金型から取り出した後、ゴム組成物２ａの表面を表面温度が１７０℃となるように１０分間加熱し、ゴム組成物２ｂの表面を表面温度が１５０℃となるように５分間加熱した。この加硫方式を表１において「実施例」という。 (1) In a vulcanizer, the mold temperature was set at 180 ° C. for 12 minutes, and after removing this from the mold, the surface of the rubber composition 2a was heated for 10 minutes so that the surface temperature was 170 ° C., The surface of the rubber composition 2b was heated for 5 minutes so that the surface temperature became 150 ° C. This vulcanization method is referred to as “Example” in Table 1.

（２）加硫機において金型温度を１８０℃として１５分間加硫し、これを金型から取り出した後、室温（２５℃）のもとで放置した。この加硫方式を表１において「従来例」という。 (2) In a vulcanizer, the mold temperature was set at 180 ° C. and vulcanized for 15 minutes. After taking out from the mold, the mold was left at room temperature (25 ° C.). This vulcanization method is referred to as “conventional example” in Table 1.

（３）加硫機において金型温度を１８０℃として１３．５分間加硫し、これを金型から取り出した後、室温（２５℃）のもとで放置した。この加硫方式を表１において「比較例１」という。 (3) In a vulcanizer, the mold temperature was set to 180 ° C. and vulcanized for 13.5 minutes. After taking it out of the mold, it was left at room temperature (25 ° C.). This vulcanization method is referred to as “Comparative Example 1” in Table 1.

（４）加硫機において金型温度を１８０℃として１２分間加硫し、これを金型から取り出した後、トレッド表面全体をトレッド表面温度が１７０℃となるように１０分間加熱した。この加硫方式を表１において「比較例２」という。 (4) Vulcanization was performed at a mold temperature of 180 ° C. for 12 minutes in a vulcanizer, and this was taken out of the mold, and then the entire tread surface was heated for 10 minutes so that the tread surface temperature was 170 ° C. This vulcanization method is referred to as “Comparative Example 2” in Table 1.

表１より、ゴム組成物２ａ及び２ｂがそれぞれ適正加硫に至った本発明の加硫方式による実施例に比較して、従来例及び比較例２ではゴム組成物２ｂが過加硫の状態にあり、比較例１ではゴム組成物２ａが加硫不足の状態にあり、いずれの加硫方式でもゴム物性の適正化が図られていないことがわかる。 From Table 1, compared with the Example by the vulcanization | cure system of this invention in which rubber composition 2a and 2b each reached | attained appropriate vulcanization, in the conventional example and the comparative example 2, the rubber composition 2b was in the state of overvulcanization. In Comparative Example 1, it can be seen that the rubber composition 2a is in a state of insufficient vulcanization, and the rubber properties are not optimized in any vulcanization method.

本発明の実施形態による空気入りタイヤの製造方法により加硫成形された空気入りタイヤの一例を示す断面図である。It is sectional drawing which shows an example of the pneumatic tire vulcanized-molded by the manufacturing method of the pneumatic tire by embodiment of this invention.

符号の説明Explanation of symbols

１空気入りタイヤ
２トレッド部
２ａ、２ｂゴム組成物 DESCRIPTION OF SYMBOLS 1 Pneumatic tire 2 Tread part 2a, 2b Rubber composition

Claims

トレッド部の幅方向に加硫速度の異なる複数種類のゴム組成物を配置した空気入りタイヤを加硫成形するに際して、前記ゴム組成物のうち加硫速度が最も速いゴム組成物を基準にして定められた加硫時間又はそれより短い時間にわたり、加硫機によりタイヤの加硫を行った後、該タイヤを加硫金型から取り出して、前記トレッド部に配置された複数種類のゴム組成物がそれぞれ適正加硫に至るまで、前記トレッド部を前記ゴム組成物の加硫速度に応じてトレッド表面側から加熱することにより追加加硫を施すようにした空気入りタイヤの製造方法。 When vulcanizing a pneumatic tire in which a plurality of types of rubber compositions having different vulcanization speeds are arranged in the width direction of the tread portion, the rubber composition having the fastest vulcanization speed among the rubber compositions is determined as a reference. After vulcanizing the tire with a vulcanizer over a given vulcanization time or shorter, the tire is removed from the vulcanization mold and a plurality of types of rubber compositions disposed in the tread portion are provided. A method for producing a pneumatic tire in which additional vulcanization is performed by heating the tread portion from the tread surface side according to the vulcanization speed of the rubber composition until proper vulcanization is achieved.

前記追加加硫において、各ゴム組成物の表面温度が前記加硫機における金型温度Ｔ（℃）に対して以下の関係になるようにした請求項１に記載の空気入りタイヤの製造方法。
Ｔａ≧Ｔｘ≧Ｔｂ
Ｔ≧Ｔａ≧Ｔ−５０℃
Ｔ≧Ｔｂ≧Ｔ−１５０℃
ただし、Ｔａは加硫速度が最も遅いゴム組成物の表面温度、Ｔｂは加硫速度が最も速いゴム組成物の表面温度、Ｔｘは加硫速度が中間であるゴム組成物の表面温度を示す。 The method for producing a pneumatic tire according to claim 1, wherein in the additional vulcanization, the surface temperature of each rubber composition has the following relationship with the mold temperature T (° C) in the vulcanizer.
Ta ≧ Tx ≧ Tb
T ≧ Ta ≧ T−50 ° C
T ≧ Tb ≧ T−150 ° C.
However, Ta represents the surface temperature of the rubber composition having the slowest vulcanization rate, Tb represents the surface temperature of the rubber composition having the fastest vulcanization rate, and Tx represents the surface temperature of the rubber composition having an intermediate vulcanization rate.

前記追加加硫における加熱をガスの噴き付け、赤外線の照射又は発熱体の接触により行う請求項１又は２に記載の空気入りタイヤの製造方法。 The method for manufacturing a pneumatic tire according to claim 1 or 2, wherein heating in the additional vulcanization is performed by spraying gas, irradiating with infrared rays, or contacting a heating element.

請求項１〜３のいずれか１項に記載の空気入りタイヤの製造方法により製造された空気入りタイヤ。 The pneumatic tire manufactured by the manufacturing method of the pneumatic tire of any one of Claims 1-3.