KR101582049B1

KR101582049B1 - Pneumatic Tire with Silica

Info

Publication number: KR101582049B1
Application number: KR1020140131415A
Authority: KR
Inventors: 신윤정
Original assignee: 금호타이어 주식회사
Priority date: 2014-09-30
Filing date: 2014-09-30
Publication date: 2015-12-31

Abstract

The present invention relates to a pneumatic tire applied with silica, which uses silica rubber as a base of tread rubber to improve rotation resistance performance. A static electricity release path (10) is formed from a wheel to a surface of a tread (20) for electricity generated inside a vehicle or a tire to be discharged to a road surface. A static electricity release path guide (15) formed by rubber which has higher hardness than static electricity release path rubber is arranged on both sides of the static electricity release path (10) to block flow of rubber in a vulcanization process.

Description

[0001] Description [0002] Pneumatic Tire with Silica [0003]

The present invention relates to a silica-applied pneumatic tire using silica rubber as a base of a tread rubber for improving rotational resistance performance, and more particularly to a pneumatic tire for silica applied with a silica rubber as a base of a tread rubber, And the static electricity discharge path is not released during the vulcanization process.

Generally, pneumatic tires are manufactured by mixing semi-finished products such as a cacass, a tread, a belt layer, an inner liner, etc. by mixing the rubber, And the green case is put into a mold, and then the vulcanization process is performed to apply a constant temperature and pressure to produce the finished product tire.

As shown in FIG. 1, the pneumatic tire manufactured through the above process comprises an inner liner 51 made of a special rubber to enhance the permeability to the air injected into the pneumatic tire, A carcass ply 52 formed of a fabric cord, a tread 57 forming a ground surface of the tire, and a tread (not shown) for reinforcing fatigue resistance against a bending and stretching load corresponding to a skeleton, A side wall 53 for protecting the carcass ply 52, a bead portion 54 for mounting the tire to the rim and an end of the inner liner 51 A specimen gum 55 for wrapping and reinforcing the bead 54 and an apex 56 positioned above the bead 54.

On the other hand, there is a strong demand for improving the fuel consumption and the wet resistance of the wet road surface by increasing the rotational resistance in accordance with the explosion of the automobile. Silica is used as a material of a tire which can satisfy both of these two performance simultaneously. That is, by adding silica, which is a kind of reinforcing material of tire rubber, to the tread portion of the tire, not only the fuel consumption is improved but also the pulling force on the wet road surface is increased.

However, when 100% silica is charged in a tie composition of a tire which is in direct contact with the road surface, the electrical conductivity is drastically lowered so that the static electricity charged in the automobile is not discharged through the tire, Which causes an uncomfortable feeling, and a spark due to static electricity causes a car explosion.

Accordingly, various methods have been proposed to complement the electrostatic characteristics of a silica filler applied to a tread rubber of a tire.

First, carbon black is added to the silica rubber composition so as not to significantly affect the electric conductivity, thereby maintaining the electrostatic discharge property. This is because there is a problem that the amount of silica is limited due to the addition of a certain amount of carbon black, and there is a problem that the rubber composition changes to black.

Although methods such as application of a discharge spray have been developed, there is a problem that the discharge can not be effectively coped with.

In addition, there is a method of improving the electrostatic discharge characteristic by attaching a sheet made of a carbon black-based rubber composition to both edges of a tread portion of a tire having a silica-based tread, but in this case, the manufacturing process becomes complicated, There is a problem that the shape can be changed.

Recently, as shown in Fig. 2, a tread 57 of a silica-applied tire in which silica rubber is used as a base of a tread rubber is provided with a static electricity discharge path from a wheel to a tread surface, So that the electrostatic discharge characteristic is improved.

However, since the static electricity discharge forming the static electricity discharge path causes the rubber flowability to be good, there is a problem that the elasticity of the rubber tends to be deformed due to the good rubber flow of the static electricity during the vulcanization of the green case have. That is, at the time of extrusion, the static discharge path extending straight to the tread surface is curved after the vulcanization and escapes to the inner side of the groove of the tire, so that the function can not be performed or its thickness is not maintained constant.

For reference, Patent Document 1 discloses a tire having a tread including silica, which includes a tread made up of two nonconductive layers and in which a tread has a circumferential insertion portion made of a conductive mixture.

Patent Document 2 discloses a tire comprising a tread grounded on a road surface and made of a silica-based rubber composition, wherein a carbon black base composition is formed on the inner side of the tread, and a carbon black base rubber composition is filled in an insertion hole formed in the tread at regular intervals A silica-coated tire structure that can discharge static electricity charged in a car smoothly to the ground is provided.

KR 10-2001-0041330 A KR 10-2001-0095422 A

SUMMARY OF THE INVENTION The present invention has been conceived to solve the problems of the prior art described above, and it is an object of the present invention to provide a tire having a tread base made of a silica-based pneumatic tire, The present invention is directed to a pneumatic tire with silica applied thereto.

In order to accomplish the above object, the present invention provides a silica-applied pneumatic tire having silica-based rubber as a base of a tread rubber and having a static discharge path extending from a wheel to a tread surface so that electricity generated in a vehicle or a tire is discharged to the road surface, A static discharge guide made of rubber having a hardness higher than that of rubber is disposed on both sides of the electrostatic discharge path so as to block the flow of rubber in the process.

In addition, according to the silica-applied pneumatic tire of the present invention, the electrostatic discharge path guide rubber forming the guide by the electrostatic discharge has the hardness of 120 to 200% as compared with the rubber by static electricity discharge.

Further, according to the silica-applied pneumatic tire of the present invention, the glass transition temperature (Tg) of the rubber is 180 DEG C or more due to the static electricity discharge.

In addition, according to the silica-applied pneumatic tire of the present invention, the width of the static electricity discharging guide is formed to be smaller than the width of the static electricity discharging path.

In addition, according to the silica-applied pneumatic tire of the present invention, the electrostatic discharge path guide is formed at the same height as the electrostatic discharge path.

The silica-applied pneumatic tire of the present invention is characterized in that the static discharge guide formed of rubber having low rubber flowability is disposed on both sides of the electrostatic discharge path formed of rubber having good rubber flowability, so that the rubber does not flow due to the static discharge in the vulcanization process, The deformation does not occur in the electrostatic discharge path of the finished tire of the vulcanized tire, and the electrostatic discharge performance using the static discharge path is improved and stabilized.

In addition, according to the silica-applied pneumatic tire of the present invention, the static electricity discharge path is not deformed from the finished product tire due to the guide due to the static electricity discharge, so that the quality of the finished product is not deteriorated due to the defect in the static electricity discharge, There is an effect to be improved.

1 is a schematic view showing a general pneumatic tire.
Fig. 2 is a schematic view showing a conventional silica-applied pneumatic tire. Fig.
3 is a schematic view showing a silica-applied pneumatic tire according to the present invention.
4 is a structural view showing a tread semi-finished product for manufacturing the silica-applied pneumatic tire of the present invention.

Hereinafter, a silica-applied pneumatic tire according to the present invention will be described with reference to the accompanying drawings.

3, silica-based rubber is used as the base of the tread rubber, and static electricity is emitted from the wheel to the surface of the tread 20 so that electricity generated inside the vehicle or tire is discharged to the road surface. And a static discharge path guide 15 made of rubber having a hardness higher than that of rubber is disposed on both sides of the electrostatic discharge path 10 so as to block the flow of rubber in the vulcanization step .

Here, the electrostatic discharge path guide rubber forming the electrostatic discharge path guide 15 preferably has a hardness of 120% or more and a hardness of about 120 to 150% as compared with the rubber in terms of electrostatic discharge. It is preferable that the glass transition temperature (Tg) of the rubber as the electrostatic discharge is 180 DEG C or more.

The width of the electrostatic discharge path 15 is formed to be smaller than the width of the electrostatic discharge path 10 and the electrostatic discharge path guide 15 is formed at the same height as the electrostatic discharge path 10 .

4, the electrostatic discharge path guide 15 is formed at the side of the tread center when the tread 20 including the silica rubber and the wing strip 30 attached to both ends thereof is manufactured. Are respectively attached to both sides of the electrostatic discharge path (10). Accordingly, when the green case fabricated by winding the tread semi-finished product is vulcanized, the guide 15 restricts the flow of the electrostatic discharge path 10 by static electricity discharge, so that the static electricity discharge path 10 is not deformed from the finished product tire . Therefore, the function of the static electricity discharge path 10 in the finished product tire is stabilized without being weakened, and the productivity of the finished product tire is improved.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be appreciated by those of ordinary skill in the art that numerous changes and modifications can be made to the invention without departing from the spirit and scope of the invention. And all such modifications and changes as fall within the scope of the present invention are therefore to be regarded as being within the scope of the present invention.

10 ... with static discharge
15 ... Guide to static discharge
20 ... Tread
30 ... wing strip

Claims

A silica applied pneumatic tire having a static-emitting path (10) extending from a wheel to a surface of a tread (20) such that silica rubber is used as the base of the tread rubber and electricity generated in the vehicle or tire is discharged to the road surface,
A guide 15 is provided on both sides of the electrostatic discharge path 10 so that the flow of rubber is blocked in the vulcanization step so that the electrostatic discharge path 10 maintains a shape extending straight to the surface of the tread on the finished product after the vulcanizing step. , And the electrostatic discharge path guide (15) is made of a rubber having a hardness higher than that of the rubber, the electrostatic discharge forming the electrostatic discharge path (10).

The method according to claim 1,
Wherein the electrostatic discharge path guide rubber forming the electrostatic discharge path guide (15) has a hardness of 120 to 200% relative to the rubber as static electricity discharge.

The method according to claim 1,
Wherein the electrostatic discharge rubber has a glass transition temperature (Tg) of 180 DEG C or higher.

The method according to claim 1,
Wherein the width of the electrostatic discharge path guide (15) is formed to be smaller than the width of the electrostatic discharge path (10) so as not to affect the performance of the tire.

5. The method according to any one of claims 1 to 4,
Wherein the electrostatic discharge path guide (15) is formed at the same height as the electrostatic discharge path (10).