JPS61190082A - Production of steel wire and steel cord - Google Patents

Abstract

PURPOSE:To improve the adhesiveness to rubber and to improve the strength of a rubber product in the stage of producing a steel wire, etc. for reinforcing the rubber product by drawing the steel wire subjected to brass plating then thinning the brass plating layer by an acid soln., etc. CONSTITUTION:The steel wire 2 subjected to the brass plating is drawn by a drawing machine 3 and is then passed through the inside of a vessel 4 for an acid soln. of a hydrochloric acid, sulfuric acid, phosphoric acid, etc., or an alkaline soln. of caustic soda, etc., and is thereby considerably decreased in the thickness of the brass plating layer in order to improve the adhesiveness of the steel wire, etc., and rubber, then such wire is embedded into the rubber in the stage of producing the composite rubber/steel material such as steel radial tire formed by embedding the steel wire or steel cord into the rubber tire. The steel wire and steel cord having the excellent moisture resistant adhesiveness and moisture- and heat resistant adhesiveness to the rubber of the tire, etc., are obtd. and the composite material with the rubber such as steel radial tire having excellent durability is obtd.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a method for manufacturing steel wire and steel cord for reinforcing rubber articles. (Prior Art) For the purpose of improving the quality and performance of rubber, steel wire Composite materials in which steel cords and steel cords are embedded in rubber are widely used. The quality and performance requirements for this rubber-metal composite are wide-ranging, but in recent years, with the development of expressways, high-speed durability and high safety of tires have been required, especially for steel radial tires that use plus-plated steel cords. There is a strong demand for increasing this.

In this regard, the adhesion between the steel cord and rubber is an extremely important quality in order to exhibit excellent quality and performance as a composite material that integrates steel cord and rubber.

Regarding this adhesive property, research has been carried out to improve steel wire, steel cord, and rubber, and the adhesion during the production of rubber products, so-called initial adhesion, has been improved, but it is difficult to use under harsh actual conditions. However, there is a problem that the good initial adhesion gradually decreases, and the current situation is that it is not in a fully satisfactory state. In particular, steel radial tires may be stored in a humid atmosphere for a long time before being installed on a car, or may be used for a long time after being installed on a car, causing scratches on the rubber and moisture infiltration, causing damage to the steel. There is a problem that the adhesion of the cord's rubber deteriorates (referred to as moisture-resistant adhesion). In addition, when the tire is mounted on a car and driven continuously for a long time, the temperature of the tire increases, which further accelerates the deterioration of adhesion due to moisture intrusion (referred to as moisture and heat resistant adhesion). By improving or solving these problems, it is possible to improve the quality and performance of rubber articles, and in particular, it is possible to improve high-speed durability and high-speed safety in methyl radial tires for automobiles.

Conventional steel wires and steel cords for rubber reinforcement are generally made by applying plus plating to the steel wire and then drawing or twisting the wire to improve moisture-resistant adhesion and moisture-heat resistance. In order to achieve this, efforts are being made to lower the Cu content in the plus or to reduce the thickness of the plus plating layer. However, Cu
If the Cu content is lowered to less than 2%, the β-plus phase will precipitate, resulting in poor wire drawability, and if the wire becomes thin, wire drawing problems such as wire breakage will easily occur, so the Cu content should be around 2%. It has reached its limit value. On the other hand, the thickness of the plus plating layer is usually determined by the amount of plating deposited in the plus plating process before wire drawing, but if the plating layer becomes too thin, the wire drawing lubricity will deteriorate, making similar problems more likely to occur. .

(Problems to be Solved by the Invention) The present invention provides a steel that has improved moisture-resistant adhesion and moisture-heat resistance by making the thickness of the plus plating layer extremely small without causing the above-mentioned wire drawing troubles. The purpose is to provide a method for manufacturing wire and steel cord.

(Means for Solving the Problems) In order to achieve the above object, the present invention reduces the thickness of the plating layer by dissolving and removing the extreme surface layer with an acidic or alkaline aqueous solution after wire drawing. I decided to make it very small.

A specific manufacturing method according to the present invention will be explained below.

FIG. 1 shows the case where the manufacturing method according to the present invention is applied to the wire drawing process.

After the plus-plated steel wire 2 that has been plus-plated in the previous process is fed out from the supply reel 1 and drawn to a predetermined wire diameter in the wire drawing machine 3, it is immediately immersed in an acidic or alkaline aqueous tank 4 to remove the plus-plating. Dissolve and remove the extreme surface layer. In this case, hydrochloric acid, sulfuric acid, phosphoric acid, etc. can be used as the acidic aqueous solution, and sodium hydroxide, potassium hydroxide, etc. can be used as the alkaline aqueous solution. This is a method in which the material is immersed in an acidic or alkaline aqueous solution tank 4, washed with water in a washing tank 5, and then completely dried in a dryer 6, and then wound onto a winding reel 7.

It is also possible to manufacture a steel cord by twisting two or more steel wires together using a wire twisting machine using the steel wire manufactured by the method shown in FIG.

FIG. 2 shows the case where the manufacturing method according to the present invention is applied to the wire twisting process.

After the two or more pieces of plus-plated m-wire 2 that have been drawn to a predetermined wire diameter (plus-plated in the previous process) are twisted together using a wire twisting machine 8, they are immediately immersed in an acidic or alkaline aqueous solution tank 4 to be coated with plus-plated wire. Dissolve and remove the extreme surface layer. After that, it is washed with water in a washing tank 5, and then completely dried with drying N6, and then wound up on a winding reel 7.

(Function) The thickness of the plus plating layer can be reduced, and moisture-resistant adhesion and moisture-heat resistant adhesiveness are good.

(Example) Plus plating was done in the previous process, and the Cu content was 63%, and the amount of plating adhered! ;,,3; Wire diameter 1, 2, with j/=9. ! ;
Using mRL's plus plating ms, the wire diameter is 0.2. ! Km, then immersion treatment in an acidic aqueous solution according to the present invention was performed under the conditions shown in Table 1 (see page 8) to dissolve and remove the extreme surface layer of the plus plating. Table 2 shows the state of plus plating after this treatment. Using the thus obtained wire, a /×5 steel cord was manufactured using a wire twisting machine, and then its initial adhesiveness, moisture-resistant adhesiveness, and moisture-heat resistant adhesiveness were examined.

Adhesion was evaluated by pasting the rubber shown in Table 3 (see page 8) on both sides of a steel cord, heating it at 1500C for 930 minutes, and then evaluating the humidity-resistant adhesion and moist heat-resistant adhesion by using the calculation environment shown in Table 2. A peel test was conducted between the steel cord and the rubber after the steel cord was left to stand, and the degree of rubber coverage of the steel cord was evaluated.

The degree of rubber coverage was determined using the left O-point perfect score method.

For comparison, adhesion was also evaluated for a /x5 steel cord twisted using drawn wire that was not immersed in an acidic or alkaline aqueous solution according to the method of the present invention.

From Table 2 (see page 2), the steel cord treated with the present invention has the same initial adhesion as the steel cord not treated with the present invention, but has 1 wet liquid adhesion resistance and wet heat resistance. It can be seen that this is extremely good.

(Effects of the Invention) According to the present invention, by performing surface treatment after wire drawing, the thickness of the plating layer can be made very small without causing wire drawing troubles such as wire thinning or wire breakage during the wire drawing process. It is possible to significantly improve moisture-resistant adhesion and moisture-heat resistant adhesiveness, which have been problems in the past.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram in which the manufacturing method of the present invention is applied to a wire drawing process and FIG. 2 to a wire twisting process. 1... Supply reel, 2... Plus plated #1 wire, 3... Wire drawing machine, 4... Acidic or alkaline aqueous solution tank, 5... Washing tank, 6... Dryer, 7 ．． ... Winding reel, 8... wire twisting machine. Figure 8: Pema Raft

Claims (1)

[Claims] 1. To produce steel wires and steel cords for reinforcing rubber articles, after drawing a plus-plated steel wire, the extreme surface layer is dissolved and removed using an acidic or alkaline aqueous solution to thin the plus-plated layer. A method for manufacturing steel wire and steel cord, characterized by: 2. To manufacture steel cords for reinforcing rubber articles, the plus-plated layer of the plus-plated steel wire is thinned after the plus-plated steel wire is drawn, and two or more wires are twisted together, or two or more wires are twisted together immediately after the wire is drawn. The method for manufacturing a steel cord according to claim 1, which is performed while twisting the above.