KR101024092B1 - Polyester tire cord fabric and tire comprising the same - Google Patents

Abstract

The present invention relates to a polyester-based tire cord paper and a tire including the same, which can reduce the damage to the shape uniformity of the tire, and can prevent the occurrence of a defect by wrinkling the selvedge deep cord inserted into the tire cord paper. .

The polyester tire cord paper is a polyester ground dip cord; And a polyester-based selvedge deep cord inserted into both selvedges of tire cord paper, wherein the selvedge deep cord has a polyester-based fineness of 50 to 90% of yarn contained in the ground dip cord. It includes yarn.

Polyester tire cord paper, selvedge deep cord, fineness, soft water, shrinkage rate

Description

Polyester-based tire cords and tires including same {Polyester TIRE CORD FABRIC AND TIRE COMPRISING THE SAME}

The present invention relates to a polyester crab tire cord containing a selvedge deep cord and a tire including the same. More specifically, the present invention can reduce the damage to the shape uniformity of the tire, while the polyester-based tire cord paper that can be prevented from the occurrence of defects wrinkled by the selvedge deep cord inserted into the tire cord paper and comprising the same It's about tires.

Representative examples of the fibers used as rubber reinforcing materials for tires include nylon fibers, cellulose fibers such as rayon, or polyester fibers. Among these, polyester-based fibers, particularly aromatic polyester-based fibers such as polyethylene terephthalate, have a benzene ring in their molecular structure and thus have a rigid molecular chain. Therefore, polyester-based tire cords prepared therefrom have elastic modulus or fatigue resistance. It has excellent advantages, high glass transition temperature, less occurrence of flat spot phenomenon, and excellent durability.

For this reason, the said polyester tire cord paper is widely used as a rubber reinforcement material for radial tires for passenger cars.

On the other hand, the tire to which the polyester-based tire cord paper is applied is generally cut to fit the tire width after topping the tire cord paper produced by inserting a plurality of polyester-based tire cord (the process of coating the inner layer rubber on the tire cord paper), Both selvedges (both ends) are overlapped to make the tire cord paper cylindrical to correspond to the tire, and then coated with rubber of the outer layer. At this time, when the tire cord paper is connected so that both selvedges overlap, the tire cord paper into which the tire cord is inserted is overlapped in two layers.

Therefore, since the connection part has higher stress and lower elongation than other parts, the connection part is less stretched than other parts. For this reason, even if air is injected into a tire including the tire cord paper, the tire cord paper and the tire do not form a completely cylindrical shape, and the shape uniformity of the tire may be impaired (that is, the portion where the tire cord paper differs from the connecting portion). These tire cords and tires can take the form of ohms in the joints.

In order to solve this problem, it has been common to apply a method of inserting a selvedge deep cord having a higher elongation into both selvedges of the tire cord paper.

For example, Korean Patent Laid-Open Publication No. 1993-0012281 and Korean Patent Laid-Open Publication No. 2001-0053349 have a manufacturing condition (for example, spinning conditions for polyester fibers) and a ground dip cord to be inserted into another portion of a tire cord paper. After manufacturing a selvedge dip cord having a higher elongation than the ground dip cord with different), the selvedge dip cord is inserted into both selvedges of the tire cord paper to manufacture a tire cord paper. .

According to this conventional technology, since both selvedges of the tire cord paper, that is, the selvedge deep cord having higher elongation are inserted into the connection portion to which the tire cord paper is connected to each other so as to have a cylindrical shape and overlap in two layers, The connection portion is stretched to a similar extent as the other portion, so that the tire cord paper and the tire can be made almost completely cylindrical and reduce the shape uniformity of the tire.

However, in this prior art, poly with a fine structure different from the ground dip cord as the selvedge dip cord is manufactured under different manufacturing conditions than the ground dip cord (e.g., spinning conditions of polyester based fibers). It includes ester-based fibers, such polyester-based fibers will exhibit a smaller shrinkage than the polyester-based fibers contained in the ground dip cord. Therefore, after spinning and stretching the polyester fiber to produce a polyester yarn, and then proceed to the dip process and heat treatment process, such as the jointed yarn and the adhesive applied to the ground dip cord, selvedge dip cord and the tire containing them When the cord paper is manufactured, even though the length of the original polyester yarn is the same, the degree of shrinkage of the yarn in the heat treatment process is different, so that the length of the selvedge deep cord inserted into the tire cord paper is often longer than that of the ground dip cord.

Due to the difference in length, defects may occur due to wrinkles in the selvedge deep cord inserted into the tire cord paper, and physical properties of the tire cord paper may be degraded.

Accordingly, the present invention is to provide a polyester-based tire cord paper that can reduce the damage to the shape uniformity of the tire, while suppressing the occurrence of a defect caused by wrinkles in the selvedge deep cord inserted into the tire cord paper.

The present invention also provides a tire comprising the tire cord paper.

The present invention is a polyester ground dip cord; And a polyester-based selvedge deep cord inserted into both selvedges of tire cord paper, wherein the selvedge deep cord has a polyester-based fineness of 50 to 90% of yarn contained in the ground dip cord. It provides a polyester-based tire cord paper containing a yarn.

The present invention also provides a tire including the tire cord paper.

Hereinafter, the present invention will be described in more detail.

Throughout the present specification, the term "polyester-based deep cord" is manufactured by carrying out a dip process and a heat treatment process in which a polyester-based yarn obtained by spinning and stretching a polyester-based fiber is spliced and then coated with an adhesive thereto. By means of a tire cord, a plurality of such tire cords are inserted to produce a polyester tire cord paper.

In addition, the term "selvage" means both ends of the tire cord paper connected to each other such that the tire cord paper has a cylindrical shape corresponding to the tire. Typically, the "selvage" means a portion corresponding to 5 to 7 tire cords (polyester-based deep cords) inserted at both ends of the tire cord paper.

In addition, "selvedge deep cord" means a tire cord inserted into at least one strand on both selvedges of the tire cord paper, and "ground deep cord" means a plurality of tire cords (polyester-based) inserted into the tire cord paper. Deep code), except for "selvedge deep code". Typically, the "selvedge deep code" shows higher elongation compared to "ground deep code".

On the other hand, the polyester tire cord paper of the present invention, polyester ground dip cord; And a polyester-based selvedge deep cord inserted into both selvedges of tire cord paper, wherein the selvedge deep cord has a polyester-based fineness of 50 to 90% of yarn contained in the ground dip cord. It includes yarn.

In the tire cord paper of the present invention, the selvedge dip cord may have 130 to 200% of the number of years of the ground dip cord.

That is, the tire cord paper of the present invention includes a ground dip cord and a selvedge dip cord inserted into at least one strand on both selvedges. In particular, the selvedge dip cord has a polyester having a lower fineness than the ground dip cord. It is made from a system yarn. In addition, the selvedge deep cord may be manufactured by twisting the polyester yarn with a softer water than that of the ground dip cord in the process of twisting the polyester yarn. The selvedge deep cord manufactured as described above is manufactured from a polyester-based yarn that has a small fineness (thickness) compared to the ground dip cord and is much twisted, and thus may exhibit lower modulus and higher elongation than the ground dip cord. Therefore, in the tire cord paper of the present invention, as the selvedge deep cord having a higher elongation is inserted into both selvedges, even if both selvedges of the tire cord paper are connected to each other and overlapped in two layers, these connecting portions are different portions. The tire cord paper and the tire including the tire may be formed to have a nearly perfect cylindrical shape when the air cord is injected. Therefore, it is possible to reduce the damage of the form uniformity of the tire by using the tire cord paper.

Further, in the tire cord paper, since the selvedge deep cord is manufactured to have a higher elongation than the ground dip cord by adjusting only the yarn thickness and the number of years, other manufacturing conditions of the selvedge dip cord (for example, The spinning condition of the polyester fiber) does not need to be different from that of the ground dip cord, and the microstructure of the polyester fiber included in the selvedge dip cord does not need to be different from the ground dip cord. Therefore, since the shrinkage ratio of the polyester fiber included in the selvedge dip cord can be maintained in a range similar to the ground dip cord, the length of the selvedge dip cord inserted into the tire cord paper is similar to that of the ground dip cord. Can be maintained. Therefore, the selvedge deep cord inserted into the tire cord paper can be suppressed from being wrinkled and deterioration of physical properties of the tire cord paper.

In summary, by applying the tire cord, it is possible to reduce the damage of the uniformity of the tire, and the difference in length between the selvedge dip cord and the ground dip cord may occur, resulting in a failure of the tire cord. This fall can be suppressed.

On the other hand, in the tire cord of the present invention, the fineness of the polyester-based yarn contained in the selvedge deep cord is smaller (50 to 90%) than the ground dip cord, for example, the yarn of the ground dip cord The fineness may be between 1000 and 2000 deniers, and the yarn fineness of the selvedge deep cord may be between 500 and 1800 deniers. Thus, even when the physical properties of the tire cord paper including the ground dip cord and selvedge deep cord are properly maintained, when both selvedges of the tire cord paper are connected to each other and overlapped in two layers, the stress and the elongation of the connection part are different from those of the other parts. Similarly, since the tire cord paper may be uniformly expanded as a whole to form an almost perfect cylindrical shape when air is injected, the shape uniformity of the tire may be further reduced.

In addition, the selvedge deep code may have a greater number of years (eg, 130 to 200%) than the ground dip code, for example, the ground dip code may have a number of years of 250 to 500 TPM, The selvedge deep code may have a soft water of 300 to 800 TPM. As a result, while the physical properties of the tire cord paper are properly maintained, the shape uniformity of the tire cord paper and the tire may be further reduced.

Further, in the tire cord paper of the present invention, the selvedge dip cord is 6.0 to 8.0 g / d in consideration of the physical properties of the tire cord paper including the same or the elongation of both selvedges of the tire cord paper into which the selvedge dip cord is inserted. Strength and 5.5 to 8.0% of the central body (@ 4.5 kg).

In addition, in the tire cord paper, the selvedge dip cord may have a shrinkage of 40 to 150% of the ground dip cord. More specifically, the ground dip cord may have a dry heat shrinkage ratio of 0.4-1.4% measured under conditions of 177 ° Cⅹ2 minutesⅹ226g, and the selvedge deep cord may be 0.2-2.1%. As a result, the shrinkage ratio of the selvedge deep cord and the ground deep cord is maintained in a similar range, so that the length of the selvedge deep cord inserted into the tire cord paper may not be substantially equal to or significantly different from the ground dip cord. It is possible to suppress the occurrence of a defect or deterioration in physical properties of the tire cord paper by pleating the paper deep cord.

The selvedge deep cord may be inserted into at least one strand of both selvedges of the tire cord paper, and more preferably, at least 2 to 5 strands of the selvedge deep cord may be inserted into both selvedges of the tire cord paper. Thus, when both selvedges of the tire cord paper are connected to each other and overlapped in two layers, the stress and elongation of these connecting portions are adjusted similarly to the other portions, thereby making it easier to suppress damage to the form uniformity of the tire.

In addition, as the polyester yarn included in the ground dip cord and selvedge dip cord, any polyester yarn applicable to tire cord paper may be used, and among these, polyethylene terephthalate yarn may be used.

Meanwhile, the above-described tire cord paper, the ground dip cord and selvedge dip cord included therein may be manufactured as follows according to a conventional manufacturing method.

First, the polyester fiber is spun and stretched to produce a polyester yarn, which is twisted and twisted with a predetermined soft water. Thus, the ground dip cord and the selvedge dip cord are manufactured by performing a dip process and a heat treatment process for applying an adhesive to the polyester-based yarn twisted and twisted. At this time, the manufacturing conditions of the ground dip cord and the selvedge dip cord are mostly the same, except that the fineness of the polyester-based yarn and the number of softenings in the ply-twisted yarn process are manufactured. Thus, the above-described polyester tire cord paper of the present invention can be manufactured using the ground dip cord and selvedge dip cord.

In addition to the manufacturing methods and conditions described above, other specific manufacturing methods and conditions depend on conventional polyester tire cords and tire cord paper manufacturing methods.

As described above, the polyester-based tire cord paper of the present invention can exhibit uniform stress and elongation even if the selvedge is formed in two layers by overlapping two selvedges in a cylindrical shape. Therefore, it is possible to prevent the tire including the same to form a nearly complete cylindrical shape to impair the shape uniformity of the tire. In addition, the tire cord paper may have a fine structure and shrinkage rate similar to that of the ground dip cord, so that the selvedge deep cord included therein may have a length similar to that of the ground dip cord. It is possible to suppress the occurrence of defects or deterioration of the physical properties of the cord paper.

On the other hand, the present invention provides a tire including the tire cord paper described above. These tires are cut according to the tire width after topping the tire cord paper (the process of applying the inner layer rubber to the tire cord paper) according to a conventional manufacturing method, and both selvedges (both ends) thereof are overlapped and connected to each other. The cord can be made into a cylindrical shape corresponding to a tire and then coated with rubber of an outer layer.

In the tire of the present invention, the tire cord paper and the tire cord including the two selvedges connected to each other can be uniformly exhibited uniform elongation and stress as a whole, so that the tire cord paper and the tire including the tire at the time of air injection can be almost completely cylindrical. have. Thus, the tire of the present invention can exhibit excellent shape uniformity.

In addition, since the tire cord paper does not have a large difference in length between the selvedge deep cord and the ground dip cord, the selvedge deep cord is hardly wrinkled. Therefore, such a tire cord paper is less likely to generate defects and can exhibit excellent physical properties, so that tires including the same can also exhibit excellent overall physical properties.

As described above, the tire cord paper of the present invention has a nearly perfect cylindrical shape to enable the provision of a tire showing excellent shape uniformity, while having less occurrence of defects and excellent physical properties.

Therefore, the tire cord paper of the present invention can be used to provide a tire having excellent running performance and other characteristics.

Hereinafter, the configuration and effects of the present invention will be described in more detail with reference to specific examples and comparative examples in order to help understanding of the present invention. However, the following examples are only intended to more clearly understand the present invention, and the present invention is not limited to the following examples.

 [Example]

Example 1

The polyester polymer (polyethylene terephthalate polymer) having an intrinsic viscosity of 1.15 was melt spun at a spinning speed of 3000 m / min and a spinning temperature of 290 to 310 ° C, cooled and solidified at 40 to 60 ° C, and stretched at a draw ratio of 1.9 to be poly An ester yarn (polyethylene terephthalate yarn) was prepared. At this time, the fineness of the polyester yarn was adjusted to 1300 denier.

The polyester yarn was twisted and twisted with 360 TPM soft water, and the adhesive was applied to the polyester yarn thus twisted and then heat treated at 240 ° C. to prepare a ground dip cord.

Meanwhile, except that the fineness of the polyester-based yarn is adjusted to 1000 denier, and the polyester-based yarn is twisted and twisted by twisting the polyester-based yarn with soft water of 500 TPM in the process of the twisted yarn, under the same conditions and methods as the ground dip cord. Selvedge dip cords were prepared.

Tire cord paper was manufactured using the ground dip cord and selvedge dip cord. At this time, the selvedge deep cord was inserted into the first to third deep cords from both ends of the tire cord paper.

Example 2

In the manufacturing process of the selvedge dip cord, ground dip cord, selvedge dip cord and the same method as in Example 1 except that the polyester-based yarn (polyethylene terephthalate yarn) twisted and twisted with a soft water of 600 TPM Tire cord paper was produced.

Example 3

In the manufacturing process of the selvedge dip cord, ground dip cord, selvedge dip cord and the same method as in Example 1 except that the polyester-based yarn (polyethylene terephthalate yarn) twisted and twisted with 700TPM soft water Tire cord paper was produced.

Comparative Example 1

Tire cord paper was manufactured in the same manner as in Example 1, except that the tire cord paper was manufactured by manufacturing and inserting only the ground dip cord without separately manufacturing the selvedge dip cord.

Comparative Example 2

A ground dip cord was manufactured in the same manner as in Example 1.

However, Selvedge deep cord was prepared as follows.

First, melt spinning a polyester polymer (polyethylene terephthalate polymer) having an intrinsic viscosity of 1.15 at a spinning speed of 2500 m / min and a spinning temperature of 290 to 310 ° C., cooling and solidifying at 40 to 60 ° C., and then at a draw ratio of 1.2. Stretching produced a polyester yarn (polyethylene terephthalate yarn). At this time, the fineness of the polyester-based yarn was adjusted to 1300 denier as in the manufacturing process of the ground dip cord.

In addition, the polyester yarn is twisted and twisted with twisted water of 360 TPM as in the manufacturing process of the ground dip cord, and the adhesive is applied to the polyester yarn thus twisted yarn and heat treated at 240 ° C. Was prepared.

Tire cord paper was manufactured using the ground dip cord and selvedge dip cord. At this time, the selvedge deep cord was inserted into the first to third deep cords from both ends of the tire cord paper.

The physical properties of the ground dip cord, selvedge dip cord and tire cord paper manufactured as described above were measured by the following method, and the results are shown in Tables 1 and 2.

Strength: In accordance with ASTM D885, the strength was measured at a tensile speed of 300 mm / min, a sample length of 250 mm, an ambient temperature of 25 ° C., and 65% RH using an Instron low-strength tensile tester.

Medium weight: Elongation under 6.75 g / d load was measured using an Instron low speed tensile tester under tensile conditions of 300 mm / min, sample length 250 mm, ambient temperature 25 ° C. and 65% RH.

Shrinkage: The shrinkage was measured under a total load of 226 g for 2 minutes at a temperature of 177 ° C. using a dry heat shrinkage tester manufactured by Testrite.

Length variation of the tire (shape uniformity of the tire; mm): After topping the tire cord paper produced in the above Examples and Comparative Examples, the tire cord paper was cut to fit the width of the tire, and both selvedges were connected to each other so that the tire cord was cylindrical. Made with. Thereafter, rubber was coated on the cylindrical outer layer to manufacture a tire. When the air was injected into the tire thus manufactured, the uniformity of the tire was evaluated by measuring the difference between the average length of the tire cord paper extending at the connecting portions of both selvedges and the average length of the tire cord extending at the other portions.

Length difference between the selvedge dip cord and the ground dip cord (mm): In the tire cord paper manufactured in the examples and comparative examples, the difference in length between the selvedge dip cord and the ground dip cord is measured, and the tire is We evaluated how wrinkled the selvedge deep cords were inserted into the cords.

[Table 1] Physical properties of ground deep code and selvedge deep code

ground
Deep code
(Examples 1-3, Comparative Examples 1 and 2) Selvedge
Deep code
(Example 1) Selvedge
Deep code
(Example 2) Selvedge
Deep code
(Example 3) Selvedge
Deep code
(Comparative Example 2) Strength (g / d) 7.0 6.9 6.7 6.6 5.2 Majority (%) 3.2 6.5 7.0 7.4 8.2 Shrinkage (%) 0.8 0.5 0.4 0.3 -0.8

[Table 2] Properties of Tire Cord Paper

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Tire Length Deformation (mm) 0.26 0.33 0.31 2.12

Dent & burge 0.41 Length difference (mm) 0.6 0.7 0.9 0.0 -3.1

Referring to Tables 1 and 2, the tire cord papers of Examples 1 to 3 have higher elongation of the selvedge deep cord than the ground dip cord, and in tires manufactured using the cord cord, the average length of the tire cord paper extended at both connecting portions of the selvedge The average lengths stretched in and other parts do not show much difference. Thus, it has been found that the tire cord paper of Examples 1 to 3 can provide a tire that is almost completely cylindrical and has almost no form uniformity damage.

In addition, as the tire cord papers of the first to third embodiments have a microstructure similar to that of the ground dip cord and thus a similar shrinkage rate, the tire cord paper between the selvedge deep cord and the ground dip cord inserted into the tire cord paper may be used. The difference in length is not large. Accordingly, it has been found that the tire cord papers of Examples 1 to 3 are hardly wrinkled in the selvedge deep cord, so that defects are small and exhibit excellent physical properties.

In addition, the tire cord paper of Examples 1 to 3 may exhibit excellent physical properties suitable for being applied to tires, including ground dip cords and selvedge dip cords having excellent strength.

On the other hand, as the tire cord paper of Comparative Example 1 is manufactured only with the ground deep cord, the average length of the tire cord paper extending in the connecting portion of both selvedges is significantly smaller than the average length of the other portion extending. Therefore, a tire manufactured using such a tire cord paper has a shape in which a portion corresponding to the connecting portion has a ohm width, thereby causing a relatively large loss of shape uniformity.

In addition, although the tire cord paper of Comparative Example 2 can reduce the damage to the shape uniformity of the tire, as the selvedge dip cord inserted into the tire cord paper shows a smaller shrinkage rate than the ground dip cord, the tire manufactured using the tire cord paper In the code, the selvedge deep code has a larger length than the ground deep code. Due to the length difference, wrinkles are generated in the selvedge deep cord, and it is confirmed that defects of the tire cord paper are not generated in a small amount and overall physical properties are also reduced.

Claims (7)

Polyester ground dip cords; And A polyester-based selvedge deep cord inserted into at least one strand of both selvedges of tire cord paper, The selvedge deep cord includes a polyester-based yarn having a fineness of 50 to 90% of the yarn included in the ground dip cord, The selvedge deep cord is a polyester-based tire cord paper having a shrinkage of 40 to 150% of the ground dip cord. The method of claim 1, The selvedge deep cord is a polyester-based tire cord having a soft water of 130 to 200% of the ground dip cord. The method of claim 1, The selvedge deep cord is a polyester-based tire cord paper exhibiting strength of 6.0 to 8.0g / d and the middle body (@ 4.5kg) of 5.5 to 8.0%. delete The method of claim 1, The selvedge deep cord is a polyester-based tire cord paper inserted into at least two to five strands on both sides of the tire cord paper selvedge. The method of claim 1, The polyester-based yarn included in the ground deep cord and selvedge deep cord is a polyester-based tire cord paper that is a polyethylene terephthalate yarn. A tire comprising the tire cord of any one of claims 1 to 3 and 5 to 6.