阅读说明：本技术 一种带束层钢帘线用橡胶组合物 (Rubber composition for belted layer steel cord ) 是由 李宜栋 尚吉永 蔡安成 张学波 唐俊萍 李学智 于 2020-04-16 设计创作，主要内容包括：本发明涉及钢帘线技术领域,具体涉及一种带束层钢帘线用橡胶组合物。以100重量份橡胶组分为基础,所述的橡胶组合物包括(A)2.5－4重量份的硫磺、(B)0.5－5重量份的间苯二酚甲醛树脂、(C)0.3－3重量份三聚氰胺甲醛树脂和(D)新葵酸钴,且(D)新葵酸钴中钴含量为0.05－0.8重量份。降低了橡胶组合物老化后的断裂性能的下降率,提高了金属材料的粘附力,尤其是抑制了轮胎行驶时橡胶组合物从钢制帘线脱离。(The invention relates to the technical field of steel cords, in particular to a rubber composition for belted layer steel cords. The rubber composition comprises (A) 2.5-4 parts by weight of sulfur, (B) 0.5-5 parts by weight of resorcinol-formaldehyde resin, (C) 0.3-3 parts by weight of melamine-formaldehyde resin and (D) cobalt neodecanoate, wherein the cobalt content in the cobalt neodecanoate is 0.05-0.8 part by weight based on 100 parts by weight of rubber components. The reduction rate of the fracture property of the rubber composition after aging is reduced, the adhesion of the metal material is improved, and particularly, the rubber composition is inhibited from separating from the steel cord when the tire is running.)

1. A rubber composition for a belt steel cord, characterized in that: the rubber composition comprises (A) 2.5-4 parts by weight of sulfur, (B) 0.5-5 parts by weight of resorcinol-formaldehyde resin, (C) 0.3-3 parts by weight of melamine-formaldehyde resin and (D) cobalt neodecanoate, wherein the cobalt content in the cobalt neodecanoate is 0.05-0.8 part by weight based on 100 parts by weight of rubber components.

2. The rubber composition for belt steel cord according to claim 1, characterized in that: the effective content of the sulfur (A) is 80 percent, the oil is 20 percent, and the sulfur content of the sulfur (A) is 2.5 to 4 weight parts.

3. The rubber composition for belt steel cord according to claim 1, characterized in that: the content of the resorcinol-formalin resin (B) is 0.5-5 parts by weight.

4. The rubber composition for belt steel cord according to claim 1, characterized in that: the content of the melamine formaldehyde resin (C) is 0.3 to 3 parts by weight.

5. The rubber composition for belt steel cord according to claim 1, characterized in that: the content of the new cobalt decanoate (D) is 0.05 to 0.8 weight portion.

6. The rubber composition for belt steel cord according to claim 1, characterized in that: the rubber composition further comprises a reinforcing agent.

7. The rubber composition for belt steel cord according to claim 6, characterized in that: the reinforcing agent is carbon black, and the content of the carbon black is 50-75 parts by weight.

8. The rubber composition for belt steel cord according to claim 6, characterized in that: the reinforcing agent is an antioxidant, and the content of the antioxidant is 0.5-2 parts by weight.

Technical Field

The invention relates to the technical field of steel cords, in particular to a rubber composition for belted layer steel cords.

Background

The rubber composition for coating the surface of the belt steel cord needs to have a certain adhesion to the steel cord. In order to improve the adhesion, the traditional method is to add cobalt salt, resorcinol and other components into the rubber composition, however, the components can generate a large amount of irritant smoke during the processing of the rubber mixture, thereby causing environmental pollution.

To solve such problems, a method of using resorcinol-formalin resin instead of resorcinol, solving the generation of irritating fumes during processing, and inhibiting the rubber composition from being released from the steel cords, while satisfying the adhesion, is disclosed.

Disclosure of Invention

In view of the above-mentioned disadvantages, the present invention provides a rubber composition for a belt steel cord.

The technical scheme adopted by the invention for solving the technical problems is as follows: the invention provides a rubber composition for a belt steel cord, which comprises (A) 2.5-4 parts by weight of sulfur, (B) 0.5-5 parts by weight of resorcinol-formaldehyde resin, (C) 0.3-3 parts by weight of melamine-formaldehyde resin and (D) cobalt neodecanoate, wherein the cobalt content in the cobalt neodecanoate is 0.05-0.8 part by weight based on 100 parts by weight of a rubber component.

Furthermore, the effective content of the sulfur (A) is 80 percent, the oil is 20 percent, and the sulfur content of the sulfur (A) is 2.5 to 4 parts by weight.

Further, the content of the resorcinol-formalin resin (B) is 0.5-5 parts by weight.

Further, the content of the melamine formaldehyde resin (C) is 0.3 to 3 parts by weight.

Further, the content of the new cobalt decanoate (D) is 0.05 to 0.8 weight part.

Further, the rubber composition also comprises a reinforcing agent.

Further, the reinforcing agent is carbon black, and the content of the carbon black is 50-75 parts by weight.

Furthermore, the reinforcing agent is an antioxidant, and the content of the antioxidant is 0.5-2 parts by weight.

The invention has the beneficial effects that: the invention provides a rubber composition for a belt steel cord, which reduces the reduction rate of fracture performance after the rubber composition is aged, improves the adhesive force of a metal material, and particularly inhibits the rubber composition from being separated from the steel cord when a tire runs.

Detailed Description

The invention provides a rubber composition for a belt steel cord, which comprises a rubber component, wherein the rubber component comprises sulfur (A), resorcinol-formaldehyde resin (B), melamine-formaldehyde resin (C) and cobalt neodecanoate (D).

The rubber component of the present invention is not particularly limited, and examples thereof are diene rubbers such as: natural Rubber (NR), Styrene Butadiene Rubber (SBR), Butadiene Rubber (BR), and butyl rubber, which are commonly used in the rubber industry. Among them, NR is preferable in view of almost 100% cis structure of isoprene and excellent tensile strength compared with other rubber components. The rubber component may be one kind of rubber or two or more kinds of rubbers may be used together.

The sulfur (A) of the present invention contains 80% of effective sulfur content and 20% of oil (Furex chemical Co., Ltd.).

The sulfur content of the sulfur (A) is at least 2.5 parts by weight, preferably at least 2.75 parts by weight, based on 100 parts by weight of the rubber component. When the content is less than 2.5 parts by weight, sulfur is not sufficiently supplied to the coating of the steel cord, and the adhesion is weakened. Meanwhile, the content is at most 4 parts by weight, preferably at most 3.75 parts by weight. When the content exceeds 4 parts by weight, the sulfur crosslinking density becomes large and the resistance to break and elongation at break become small.

The resorcinol-formalin resin (B) of the present invention (Indian Co.).

The content of the resorcinol-formalin resin (B) is at least 0.5 part by weight, preferably at least 1 part by weight, based on 100 parts by weight of the rubber component. When the content is less than 0.5 part by weight, the resin has low crosslinking density and hardness. Meanwhile, the content is at most 5 parts by weight, preferably at most 3 parts by weight. When the content exceeds 5 parts by weight, the calorific value becomes large.

The melamine formaldehyde resin (C) of the present invention (Cyanite Corp., USA).

The melamine formaldehyde resin (C) is contained in an amount of at least 0.3 part by weight, preferably at least 0.6 part by weight, based on 100 parts by weight of the rubber component. When the content is less than 0.3 part by weight, the hardness is insufficient. Meanwhile, the content is at most 3 parts by weight, preferably at most 2.5 parts by weight. When the content exceeds 3 parts by weight, the calorific value becomes large.

The cobalt neodecanoate (D) of the present invention has an effect of crosslinking the cord and the rubber, and therefore, the adhesion between the cord and the rubber can be improved by the cobalt neodecanoate (D).

The content of the cobalt neodecanoate (D) is at least 0.05 parts by weight, preferably at least 0.1 parts by weight, based on 100 parts by weight of the rubber component. When the content is less than 0.05 parts by weight, the adhesion between the steel cord and the rubber is insufficient. Meanwhile, the content thereof is at most 0.8 part by weight, preferably at most 0.2 part by weight. When the content exceeds 0.8 parts by weight, oxidation and degradation of the rubber are significant and the fracture properties are deteriorated.

In the rubber component of the present invention, in addition to sulfur (a), resorcinol-formaldehyde resin (B), melamine-formaldehyde resin (C) and cobalt neodecanoate (D), reinforcing agents such as carbon black and silica, zinc oxide, antioxidants and vulcanization accelerators may be added accordingly.

When carbon black is blended as a reinforcing agent, the content of carbon black is preferably 50 to 75 parts by weight based on 100 parts by weight of the rubber component, and when the content is less than 50 parts by weight, it is difficult to obtain sufficient reinforcing effect, hardness and rigidity. When the content exceeds 75 parts by weight, the heat generation amount becomes large, the rubber composition is easily hardened, and the processability in kneading or extruding the rubber tends to be deteriorated.

Examples of the antioxidant are quinoline type antioxidants, and from the viewpoint of being able to effectively prevent oxidation and degradation of the polymer, quinoline type antioxidants are preferably used.

The content of the antioxidant is preferably at least 0.5 parts by weight, more preferably 0.7 parts by weight, based on 100 parts by weight of the rubber component. When the content is less than 0.5 parts by weight, oxidation and degradation of the polymer cannot be prevented. Meanwhile, the content thereof is preferably at most 2 parts by weight, more preferably at most 1.5 parts by weight. When the content exceeds 2 parts by weight, the coating layer of the cord fabric is damaged by the antioxidant, and the adhesion to the metal cord is easily inhibited.

The rubber composition of the present invention is coated on a steel cord to form a belt layer, which is laminated with other tire components to form an unvulcanized tire, followed by vulcanization to form a pneumatic tire (e.g., radial tire). The belt layer herein refers to a breaker layer used for a radial tire and for fastening a carcass and increasing the rigidity of a tire tread. The rubber composition of the present invention is most preferably used for coating steel cords in a belt layer in consideration of large twist due to rolling between the belt layer and another alternate belt layer caused by large tension of the belt layer due to tire pressure.

The present invention is described in detail based on the following examples, but the present invention is not limited thereto.