KR100481458B1 - Pnumeric tire with capply cord consist of Polyketone and nylon-66 - Google Patents

Abstract

The present invention relates to a pneumatic tire comprising a tire cap ply cord consisting of polyketone and nylon-66. The pneumatic tire of the present invention is composed of a composite fiber having a twist per inch (TPI) of 20 to 60 in a polyketone: nylon-66 ratio of 1: 1 to 2 to 1-2: 1. Capply code with two code array densities (Ends Per Inch, EPI).

Polyketone (POK) or nylon-66 of the cap fly cord in the present invention is characterized in that 500 ~ 2000 denia (denia).

Description

Pnumeric tire with capply cord consist of Polyketone and nylon-66}

The present invention relates to a pneumatic tire comprising a cap fly cord composed of polyketone (hereinafter referred to as 'POK') and nylon-66 (hereinafter referred to as 'N-66').

Recently, high-speed driving is frequently performed according to the luxury of passenger cars and the development of roads. Therefore, characteristics such as high-speed driving stability and durability of tires are very important. In particular, these characteristics are more important in tires having low flatness ratio, and in order to satisfy these performances, many N-66 cords are used as cap fly materials.

Looking at the chemical structure of the N-66 code, H- (HN- (CH ₂ ) ₄ -NH-CO- (CH ₂ ) ₆ )) CO) _N -OH. N-66 having the structure as described above has a high strength, excellent adhesive strength and excellent thermal stability among the fiber cord for tires, but there is a problem of high speed running performance and low durability when applied to the cap ply.

The present invention has been made to solve the above problems, can be represented by the following structural formula, the composite fiber by twisting the polyketone (POK) excellent in structural stability and durability and excellent N-66 with excellent adhesive and structural stability It is an object of the present invention to provide a pneumatic tire that can improve the durability by using the form as a cord for the cap fly of the tire.

In order to achieve the above object, the pneumatic tire of the present invention is a polyketone: nylon-66 composite fiber having a twist per inch (TPI) of 20 to 60 at a ratio of 1: 1 to 2 to 1 to 2: 1. It is characterized in that it is applied to the capfly code having a 20 to 40 code array density (Ends Per Inch, EPI).

On the other hand, polyketone (POK) and nylon-66 used as a cap fly cord in the present invention may be used 500 to 2000 denia (denia).

In the present invention, the shrinkage (160 ° C. × 15 min) of POK and N-66 used as the cap fly cord is 4% and 5%, respectively. The cord having such a shrinkage ratio can maintain better structural stability by applying POK together with N-66 than when N-66 is applied alone.

The softening point of N-66 is 230 to 235 ° C and the melting point is 250 to 260 ° C.

As shown in FIGS. 1 and 2, the cap ply 2 is located at the innermost part of the tire, that is, the site where heat is generated a lot, and above all, the cap fly 2 should be excellent in thermal stability. Excellent thermal stability can be maintained. That is, N-66 has a melting temperature of 260 ° C, and POK code does not have a melting temperature, and thus it is possible to maintain excellent thermal stability when P-P code is applied together with N-66 than when N-66 is applied alone. Reference numeral 1 is a belt.

2 shows a state in which the fiber cord 4 according to the present invention is inserted into the rubber 3.

On the other hand, when the POK: N-66 in the composite fiber configuration, it is preferable to use 1 to 2 N-66 codes per POK code or 1 to 2 POK codes per N-66. In other words, if the number of fibers constituting the cord is more than three, the structure is complicated, the physical properties can occur, and if the thickness of the cord is too thick because the practical use of three fibers constituting the cord is appropriate.

POK and N-66 used as a cap fly code in the pneumatic tire of the present invention is preferably applied between 500 to 2000 denia, when the POK and N-66 is less than 500 denia As the code usage is too small, the code strength is too low, which causes a problem that the practical use is poor. In addition, when using POK and N-66 over 2000 denia (denia), the thickness of the cord is too thick, causing a problem that the weight of the tire increases.

If the twist per inch (TPI) of the POK and N-66 is less than 20, there is a problem of maintaining the straightness of the cord and the fatigue property, and if the twist is more than 60, there is a problem of rapidly decreasing the physical properties such as the strength of the cord. As a result, the TOK between 20 and 60 is best for the POK code and N-66.

In addition, in the present invention, the arrangement density of the cap fly cord is applied in various numerical ranges, and when the arrangement density is 10 to 45 EPI, the physical properties of the cord are excellent and suitable for the purpose of the present invention. The array density of the code is preferably 10 to 45 EPI.

Hereinafter, the present invention will be described by the following comparative examples, examples and test examples. However, the scope of the present invention is not limited by these.

Comparative Example

1260 Denia Nylon-66 is twisted to have a twist of 28 and an array density of 28 EPI to make code 1260D / 2D Nylon-66 for cap plies and to apply 1 piece of Nylon-66 to a cap ply of 205 / 60R 15 for passenger tires. The strength, the median elongation, and the heat shrinkage were measured and the results are summarized in Table 1 below.

<Example>

A 1000D-1000D composite cord for a cap ply is manufactured by twisting 1000 Denia nylon-66 and 1000 Denia POK cords with a twist number of 46 and an array density of 28 EPI, and using one of the composite cords for a passenger car tire 205 / 60R 15 standard. The strength, the median elongation, and the heat shrinkage were measured and then the results are summarized in Table 1 below.

TABLE 1 Property measurement results of Comparative Examples and Examples

Item Comparative example Example Strong (kg) 23.71 24.64 Medium elongation (4.5kg) (%) 6.94 4.32 Heat Shrinkage (%) (177 ℃ × 2min, free) 4.33 1.97

<Test Example>

The cords of Comparative Examples and Examples were tested on the durability of the cap ply of each passenger car tire standard, and the results are summarized in Table 2 below.

Table 2 Test Results of Comparative Examples and Examples

Item Comparative example Example Durability (ECER-30) 1 hour 45 minutes 2 hours 15 minutes

* ECER-30: European tire durability standard test method

As can be seen from the results of Table 2, in the durable part, it can be seen that the Example is superior to the Comparative Example.

As can be seen from the results of the test example, the composite fiber of polyketone and N-66 composed of polyketone (POK) having excellent structural stability and durability and N-66 having excellent adhesive performance and structural stability as the code for cap ply according to the present invention. Applied pneumatic tires can be seen that the durability performance is improved compared to pneumatic tires using N-66 alone as a code for cap fly.

1 is a side cross-section of a tire.

2 is a detailed cross-sectional view of the cap ply according to the present invention.

<Description of the symbols for the main parts of the drawings>

1: belt 2: cap fly

3: rubber 4: fiber cord

Claims (3)

In known pneumatic tires, Polyketone (POK): A pneumatic tire comprising a capply cord consisting of a composite fiber having a twist number of 20 to 60 with nylon-66 in a ratio of 1: 1 to 2 to 1 to 2: 1. The pneumatic tire according to claim 1, wherein the arrangement density of the cap fly cord is 20 to 40 EPI. 2. The pneumatic tire according to claim 1, wherein the polyketone (POK) and the nylon-66 are 500 to 2000 denia.