KR20010019363A - Strip Rubber Composition adapted to part of belt edge for Car - Google Patents

Abstract

PURPOSE: A strip rubber composition for belt edge part of automobile is provided to reinforce adhesion strength between steel cord and rubber of tire, and improve alteration-resistance and exothermic property. CONSTITUTION: A strip rubber composition for belt edge part of automobile consists of natural and synthetic rubbers, carbon black, adhesives, sticking agent, vulcanizer and promotor. The vulcanizer is attached with golden copper layer such as copper or galvanized zinc in belt laminate. The strip rubber composition has a 15-20mm width and a 0.5-0.8mm thickness to cover the edge part of belt cord to adhere steel cord of tire to the strip rubber. The composition comprises 3-5 weight part of high resilient epoxy resin based on 100 weight part of the raw rubber.

Description

Strip rubber composition adapted to part of belt edge for Car}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt edge strip rubber composition of a tire for a passenger car and a method of adhering the same. More specifically, a belt layer rubber of a tire for a passenger car improved in adhesion between the cut belt edge and a tread rubber. To a composition.

In general, in the tire manufacturing process for passenger cars, in the forming process, a belt layer is attached to a primary case made of inner, carcass, and sidewalls, and a green case is manufactured by attaching a tread thereon to manufacture a finished product tire.

The belt layer rubber that has been used conventionally is designed as a rubber composition that has excellent adhesion to the brass layer for the purpose of improving the adhesion performance with the brass plated steel cord. The belt edge is exposed to the cord cross section without the brass plating layer. The exposed belt edge part has a problem such that the belt edge part is separated while driving and the adhesive performance with the rubber is poor, causing an accident.

The inventors of the present invention have been studying a solution to solve the problems of the prior art, in order to improve the adhesive performance with the cut belt edge portion, the resin edge of the belt rubber composition with a particularly excellent adhesive strip rubber composition The present invention has been completed by finding that the wrapping can improve the adhesiveness of the belt edge in the finished tire to improve the durability of the tire.

Therefore, an object of the present invention is to wrap the resin excellent in the belt edge portion to improve the adhesiveness between the steel cord and rubber of the finished tire as well as to improve the deformation resistance and heat generation characteristics of the belt rubber composition for passenger cars with improved tire durability To provide.

1 is a schematic diagram of a tire cross section in a state where the belt rubber composition of the present invention is applied.

<Description of the code | symbol about the principal part of drawing>

1: second belt layer 2: first belt layer

3: carcass 4: strip rubber

In general, the belt layer rubber composition is composed of natural and synthetic rubber, carbon black, adhesives, pressure-sensitive adhesives, vulcanizing agents, accelerators and the like. Among them, the composition which bonds with the brass layer of the belt layer is a vulcanizing agent and a partially low molecular weight adhesive is used as an auxiliary for improving adhesion. In the basic mechanism of adhesion between the brass layer (copper and zinc plating) and the rubber composition, an adhesive layer composed of copper sulfide and zinc sulfide layer plays a very important function in the adhesion expression. However, the trimmed belt edges do not have such a brass layer and are made of a metal composed mainly of iron, and thus, when vulcanized with an existing rubber composition, adhesiveness is lowered.

The present invention wraps the belt edge portion with a rubber composition to which high elastic epoxy resin is added as shown in FIG. 1 to improve the poor adhesion between the brass layer and the rubber composition as described above between the belt edge portion and the rubber layer without the brass layer. It is the content to improve adhesiveness.

That is, the first and second belts formed by adhering the first belt layer 2 to the outer circumferential surface of the carcass portion 3 of the tire and adhering the second belt layer 1 to the upper end of the first belt layer. It is possible to improve the adhesiveness between the cut belt edge portion and the rubber layer by wrapping the rubber composition to which the high elastic epoxy resin is added as the strip rubber 4.

A predetermined amount of high elastic epoxy resin represented by the following general formula is added to the strip rubber 4 surrounding the edge portion of the belt of the present invention. The high elastic epoxy resin has excellent adhesive properties with the belt edge portion. . Therefore, the above-mentioned epoxy resin strip rubber is effectively bonded to the edge portion of the belt, and also effectively adhered between the strip rubber and the tread rubber bonded directly to the edge portion of the conventional belt. The separation problem of the belt edge part can be prevented.

The blending amount of the high elastic epoxy resin added to the strip rubber (4) is 3 to 5 parts by weight based on 100 parts by weight of the raw material rubber, if less than 3 parts by weight can not be expected to have sufficient adhesion to the edge of the belt, If it exceeds 5 parts by weight, the physical properties of the strip rubber itself may be lowered, which is not preferable.

In addition, in the preparation of the rubber composition to which the high elastic epoxy resin is added, an adhesive aid may be added to the belt cord edge portion and the strip rubber for the purpose of improving the adhesive strength. What is necessary is just to use a commercially available thing as it is at this time, and it is not limited to a specific kind, Any one is suitable for implementing this invention. However, it is preferable to limit the adhesion aid to 1 to 10 parts by weight in relation to other components.

The strip rubber to which the high elastic epoxy resin is added has a width of about 15 to 20 mm and a thickness of about 0.5 to 0.8 mm, which is preferable not only to perform the function as the strip rubber but also to manufacture the tire.

In addition to the other composition ingredients added, for example, fillers, vulcanizing agents, vulcanization accelerators, process oils, anti-aging agents, etc. are those added to known tire rubber compositions, but are not limited to any particular one of the practice of the present invention Can be used for

Hereinafter, the scope of the present invention will be described in detail with reference to examples, but the scope of the present invention is not limited to these examples.

<Examples 1-3>

As shown in Table 1 below, 80 parts by weight of natural rubber as raw material rubber and 100 parts by weight of mixed rubber consisting of 20 parts by weight of butadiene rubber are 1.0 parts by weight of stearic acid as a vulcanizing agent and carbon black 55 as a reinforcing filler. Parts by weight, 9.0 parts by weight of zinc, 5.0 parts by weight of process oil, 1.5 parts by weight of antioxidant, 5.0 parts by weight of sulfur, 0.7 parts by weight of vulcanization accelerator, 2.5 parts by weight of adhesive, 2.0 parts by weight of adhesive aid (Example 3 is not added) and high elasticity Epoxy resin was added at 3.0, 4.0, and 5.0 parts by weight, respectively, and blended in a Banbury mixer, and the rubber composition obtained by discharging at a temperature of 160 ° C. was 18 mm wide and 0.6 mm thick to wrap belt edges and vulcanize them to produce finished tires. It was.

In addition, various physical property tests for the rubber composition obtained by the above process were tested according to ASTM standards, and the results are shown in Table 1.

<Comparative Example>

Except for adding 5.0 parts by weight of the adhesive aid without adding the high elastic epoxy resin was carried out in the same manner as in Example 1 and the results are shown in Table 1.

<Table 1> Rubber composition and tensile properties, adhesive strength, durability results

Conventional rubber Example 1 Example 2 Example 3 Natural rubber (phr) Butadiene rubber (phr) Carbon black (phr) ZnO (phr) Stearic acid (phr) Sulfur (phr) Adhesive (phr) Anti-aging agent (phr) Accelerator (phr) Process oil (phr) Adhesive aid (phr) High elastic epoxy resin (phr) 8020559.01.05.02.51.50.75.05.0 8020559.01.05.02.51.50.75.02.03.0 8020559.01.05.02.51.50.75.02.04.0 8020559.01.05.02.51.50.75.005.0 Tensile Properties Tensile Strength (kgf / cm ² ) 300% Modulus (kgf / cm ² ) Cutting Elongation (%) Hardness (Shore A) 100100100100100 1101109510595 1201209011085 10010010010590 Adhesion T-Test (kgf) Initial Adhesion Adhesion After Thermal Aging (105 ℃ / day) TCAT Test (kgf) Initial Adhesion Adhesion After Thermal Aging (105 ℃ / day) 100100100100 110110110105 120110120110 120105120105 Indoor driving durability 100 105 110 105

According to the present invention, it can be seen from Table 1 that the tensile properties, adhesion and durability increase in the rubber composition to which the high elastic epoxy resin is added as compared with the conventional rubber composition. In particular, when the high elastic epoxy resin is added in combination with the adhesive aid than the high elastic epoxy resin only, it can be seen that the increase in tensile properties, adhesion and durability increase. In addition, 300% modulus is increased when the adhesive aid and the high elastic epoxy resin are used in combination as shown in Example 2, which serves to reduce the deformation amount of the belt edge part while driving, thereby improving the relative fatigue fatigue characteristics. The present invention further has an effect of improving the heat generation characteristics compared to the conventional rubber composition.

Claims (3)

A rubber edge composition rubber composition for a passenger car, comprising 3 to 5 parts by weight of high elastic epoxy resin based on 100 parts by weight of raw rubber. The belt edge strip rubber composition according to Claim 1, wherein the adhesive aid is added in an amount of 1 to 10 parts by weight. The strip rubber composition according to claim 1, having a width of 15 to 20 mm and a thickness of 0.5 to 0.8 mm, which surrounds the belt cord edge to bond the steel cord of the tire to the strip rubber.