KR20210083182A - Tire cord, manufacturing method thereof and tire comprising same - Google Patents

Abstract

The present invention relates to a tire cord having a thin thickness and excellent durability, a method for manufacturing the same, and a tire comprising the same. The tire cord comprises a fiber base using warp comprising at least one of nylon, rayon, aramid, and polyester comprising PET; an adhesive layer; and a rubber coating layer.

Description

Tire cord, manufacturing method therefor, and tire including same {TIRE CORD, MANUFACTURING METHOD THEREOF AND TIRE COMPRISING SAME}

Cross Citation with Related Applications

This application claims the benefit of priority based on Korean Patent Application No. 10-2019-0175655 on December 26, 2019, and all contents disclosed in the literature of the Korean patent application are incorporated as a part of this specification.

technical field

The present invention relates to a tire cord, a method for manufacturing the same, and a tire including the same.

Recently, as the performance of automobiles is improved and road conditions are improved, the driving speed of automobiles is gradually increasing, so it is necessary to maintain stability and durability of tires even during high-speed driving. To this end, research on a tire cord used as a rubber reinforcing material for a tire is being actively conducted.

Tire cords can be largely classified into carcass, belts, and cap ply depending on the part and role used, and materials used for this include nylon, rayon, aramid, and polyester including PET.

At this time, the tire cord made of the above materials is generally rolled together with a rubber component for adhesion to the rubber. That is, a rolling process is involved in the tire manufacturing process. When the rolling process for bonding the tire cord and rubber is applied in the tire manufacturing process, the process cost increases, and the density of the tire increases more than necessary due to rolling. Tire weight may increase unnecessarily.

In addition, in the process of rolling rubber on a tire cord, solid rubber is generally used, and the product formed by the rolling of such solid rubber is made into a thin film of 200 μm or less, particularly 5 μm to 30 μm. It is difficult to carry, and when these products are used as reinforcing materials, the thickness and weight of the tire increase.

On the other hand, recently, tire manufacturers want to reduce the thickness of the rubber layer in order to reduce the weight of the tire and the reinforcing material. Rolling resistance (R/R) is related to the weight of the tire and has a significant impact on the fuel consumption and carbon dioxide emissions of a vehicle. For example, as the rolling resistance (R/R) increases, the energy required for driving a vehicle increases. In addition, the resistance to rotation, inclination, and acceleration of a vehicle is closely related to the weight of the vehicle. Accordingly, research is being conducted to reduce the weight of automobiles through weight reduction of tires and, as a result, to reduce energy consumption.

Accordingly, there is a demand for the development of a new tire cord having a thin thickness and excellent adhesion to rubber.

An object of the present invention is to provide a tire cord having a thin thickness and excellent durability.

Another object of the present invention is to provide a method of manufacturing a tire cord having a thin thickness and excellent durability.

Another object of the present invention is to provide a tire including the tire cord.

In the present specification, using a warp containing at least one of polyester including nylon, rayon, aramid and PET, the density between the warps is 65% or more or the number of warps per unit length (n/inch) is woven with 35 or more fiber base; and an adhesive layer formed on the fiber substrate; and a rubber coating layer formed on the adhesive layer, wherein the rubber coating layer includes synthetic rubber or natural rubber, and the application amount per unit area of the rubber coating layer to the adhesive layer is 75 to 300 g/m ^{2 A} tire cord is provided do.

In addition, in the present specification, by using a warp containing at least one of polyester including nylon, rayon, aramid and PET, the density between the warps is 65% or more or the number of warps per unit length (n/inch) 35 or more. Preparing a woven fiber substrate; forming an adhesive layer on the fiber substrate; and applying a rubber coating solution on the adhesive layer and heat-treating it to form a rubber coating layer, wherein the rubber coating layer includes synthetic rubber or natural rubber, and the application amount per unit area of the rubber coating layer to the adhesive layer is 75 to A method of making a tire cord, which is 300 g/m ^{2 , is provided.}

Further, in the present specification, a tire including the tire cord is provided.

Hereinafter, a tire cord according to a specific embodiment of the present invention, a method for manufacturing the same, and a tire including the same will be described in more detail.

As used herein, the terms “warp” and “weft” refer to a configuration used to weave a fiber base, which is one configuration of a tire cord, crossed with each other. The direction of each yarn associated with the crossing may be relative, and thus the weft yarn and warp yarns may also be relative designations.

The terminology used herein is used to describe exemplary embodiments only, and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present specification, terms such as "comprise", "comprising" or "have" are intended to designate the presence of an embodied feature, number, step, element, or a combination thereof, but one or more other features or It should be understood that it does not preclude the possibility of the presence or addition of numbers, steps, elements, or combinations thereof.

Since the present invention may have various changes and may have various forms, specific embodiments will be illustrated and described in detail below. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

In an example related to the present application, the present application relates to a tire cord.

Specifically, according to one embodiment of the invention, by using a warp containing at least one of polyester including nylon, rayon, aramid and PET, the density between the warps is 65% or more or the number of warps per unit length (n/inch) ) 35 or more woven fiber bases; and an adhesive layer formed on the fiber substrate; and a rubber coating layer formed on the adhesive layer, wherein the rubber coating layer includes synthetic rubber or natural rubber, and the application amount per unit area of the rubber coating layer to the adhesive layer is 75 to 300 g/m ^{2 A} tire cord is provided can be

The present inventors conducted research on the tire cord, confirmed through experiments that the tire cord including the above-described component has excellent durability while having a thin thickness, and completed the invention.

In addition, since the tire cord of the above embodiment has excellent adhesion to rubber, it can be strongly adhered to rubber without going through a rolling process in the tire manufacturing process, and tire manufacturing cost is reduced by not going through a rolling process, and by rolling Due to this, it is possible to prevent the density of the tire from being increased more than necessary and the weight of the tire from being unnecessarily increased.

When the tire cord of the embodiment is used as a cap ply, belt, or carcass of a tire, the rolling process may be omitted, thereby simplifying the tire manufacturing process, and reducing the thickness and overall weight of the tire. In addition, since the adhesiveness of the tire cord is greatly increased, air pockets are reduced during manufacturing of the green tire, thereby reducing the tire defect rate.

In addition, when the tire cord of the above embodiment is used for a tire, the tire weight is reduced by the tire cord having a thin thickness and having excellent rubber reinforcing performance, so that the rolling resistance (R/R) is lowered, and accordingly, the In addition to improving fuel efficiency, carbon dioxide emissions can also be lowered.

The tire cord of the embodiment includes a fiber base, and the fiber base may use a filament including at least one of nylon, rayon, aramid, and polyester including PET as a warp yarn. At this time, weaving is performed using the warp, and the density between warps during weaving is 65% or more or the number of warps per unit length (n/inch) is 35 or more.

The density between the warps represents the area occupied by the warps per inch, and can be specifically expressed as {(width of one warp strand (inch) * number of warps per inch (n)) / inch} * 100 (%). The width may be used in the same sense as the width, and in the case of a tire cord, since the cross section is substantially circular, the width may be used interchangeably with the thickness.

In one example, the lower limit of the density between the gradients may be 65% or more, 70% or more, 75% or more, 80% or more, 85% or more, 90% or more, or 95% or more. In addition, the upper limit of the density between the gradients is not particularly limited, but may be, for example, less than 100%, specifically 99% or less, 98% or less, 97% or less, 96% or less, or 95% or less. When the range of the density between the gradients satisfies the above range, it is possible to form a stable adhesive layer and secure fatigue performance, and may have a role of improving bonding strength with the rubber coating layer. In particular, when the density between the slopes is less than 65%, there is a problem in that the adhesive force is unstable and the rubber coating layer flows down.

In one example, the number of inclinations per unit length (n/inch) may be 35 or more, 40 or more, 45 or more, 50 or more, 55 or more, 60 or more, or 65 or more. The upper limit of the number of inclinations per unit area is not particularly limited, but may be, for example, 90 or less, 85 or less, 80 or less, 75 or less, 70 or less, 65 or less, or 60 or less. When the number of inclinations per unit area satisfies the above range, it is possible to form a stable adhesive layer and secure fatigue performance, and may have a role of improving bonding strength with the rubber coating layer. In particular, when the number of inclinations per unit length is less than 35, the adhesive force is unstable and there is a problem that the rubber coating layer flows down.

In one example, the fiber base may be a woven fiber base having a density of 65% or more between warps, and at the same time the number of warps per unit length (n/inch) of 35 or more. As such, when the density and the number of inclinations are simultaneously satisfied, the aforementioned adhesive force, bonding force, and fatigue resistance performance can be more stably secured. The specific density between the gradients and the number of gradients are the same as described above.

In one example, the fiber base may have a density between wefts lower than the density between warps. Like the above-described inter-warp density, the inter-weft density represents the area occupied by weft yarns per inch, specifically {(width of one weft yarn (inch) * number of weft yarns per inch (n)) / inch} * 100 ( %) can be identified.

In one example, the fibrous substrate may have a weft density in the range of 3 to 25%. Specifically, the lower limit of the weft density of the fiber base is, for example, 4% or more, 5% or more, 6% or more, 7% or more, 8% or more, 9% or more, 10% or more, 11% or more, 12% or more. or more, 13% or more, 14% or more, or 15% or more. And, the upper limit of the fiber base weft density is, for example, 24% or less, 23% or less, 22% or less, 21% or less, 20% or less, 19% or less, 18% or less, 17% or less, 16% or less, 15% or less, 14% or less, 13% or less, 12% or less, 11% or less, or 10% or less. If the weft density is less than the above range, the warp may not be stably held during the heat treatment or rubber coating process, so that the woven fabric is twisted and defects may occur. And, when the weft density exceeds the above range, it may be difficult to control the width of the product during heat treatment, and the adhesive force may be relatively low. The reason for the low adhesive strength is that the weft yarn serves to hold the warp in the tire and at the same time serves as a passage for gas in the rubber to escape. If excessive weft yarn is used, it acts as a foreign substance inside the tire, and the warp This is because the area in contact with the rubber is reduced.

In one example, the fiber base may have a lower number of weft yarns per unit length (n/inch) than the number of weft yarns per unit length.

In one example, the fiber substrate may have a number of weft yarns in the range of 5 to 30 (number of weft yarns per unit length: n/inch). Specifically, the lower limit of the number of weft yarns of the fiber base material is, for example, 6 or more, 7 or more, 8 or more, 9 or more, 10 or more, 11 or more, 12 or more, 13 or more, 14 or more, 15 or more, 16 or more, 17 or more, 18 or more, 19 or more, or 20 or more. And, the upper limit of the number of the fiber base weft is, for example, 29 or less, 28 or less, 27 or less, 26 or less, 25 or less, 24 or less, 23 or less, 22 or less, 21 or less, 20 or less, 19 or less, 18 or less, 17 or less, 16 or less, or 15 or less. If the number of weft yarns is less than the above range, the warp may not be stably held during the heat treatment or rubber coating process, so that the woven fabric is twisted and defects may occur. In addition, when the number of weft yarns exceeds the above range, it may be difficult to control the width of the product during heat treatment, and adhesion may be relatively low. The reason for the low adhesive strength is that the weft yarn serves to hold the warp in the tire and at the same time serves as a passage for gas in the rubber to escape. If excessive weft yarn is used, it acts as a foreign substance inside the tire, and the warp This is because the area in contact with the rubber is reduced.

On the other hand, the inclination may be given a twist.

At this time, the unit of twist is TPM and is defined as Twist per meter, and the degree of twist is based on the number of twists per 1 m, and twist can be given from 0 to a maximum of 250 TPM.

When twist is given to the slope, it may have a role of improving the focusing property of the tire cord and improving the fatigue performance.

In one example, the fibers (warp and/or weft) including at least one of nylon, rayon, aramid, and polyester including PET may have a fineness of 300 to 1500 de. Specifically, the lower limit of the fineness is 350 de or more, 400 de or more, 450 de or more, 500 de or more, 550 de or more, 600 de or more, 650 de or more, 700 de or more, 750 de or more, 800 de or more, 850 de or more. de or more, 900 de or more, 950 de or more, 1000 de or more, 1050 de or more, 1100 de or more, 1150 de or more, or 1200 de or more. The lower limit of the fineness is, for example, 1450 de or less, 1400 de or less, 1350 de or less, 1300 de or less, 1250 de or less, 1200 de or less, 1150 de or less, 1100 de or less, 1050 de or less, 1000 de or less , 950 de or less, 900 de or less, 850 de or less, 800 de or less, 750 de or less, or 700 de or less.

For example, a warp in which a twist of 0 to 250 TPM is imparted to a filament including at least one of polyester including rayon, aramid and PET having a fineness of 300 to 1500 de may be used.

On the other hand, the fiber substrate of the embodiment may have a thickness of, for example, 0.10 mm or more, 0.15 mm or more, 0.20 mm or more, 0.25 mm or more, 0.30 mm or more, 0.35 mm or more, or 0.40 mm or more. The upper limit of the thickness may be, for example, 0.60 mm or less, 0.55 mm or less, 0.50 mm or less, 0.45 mm or less, or 0.40 mm or less. When the fiber base material has a thickness in the above-mentioned range, it is possible to form a stable adhesive layer with constant strength and elongation at break.

Meanwhile, the tire cord of the embodiment may include an adhesive layer formed on the above-described fiber substrate.

The adhesive layer may include resorcinol-formaldehyde-latex (RFL), for example, the adhesive layer may be formed by an adhesive coating solution containing resorcinol-formaldehyde-latex (RFL) and a solvent. have.

The resorcinol-formaldehyde-latex is also referred to as "RFL" and may act as an adhesive component. Resorcinol-formaldehyde-latex can improve the affinity and adhesion between the fiber base and the rubber component, in particular, to improve the adhesion between the fiber base and the rubber coating layer in the tire cord.

Accordingly, the fiber base and the rubber coating layer in the tire cord can be stably attached without being separated from each other, and when the tire cord is applied to a tire, defects can be prevented in the manufacturing process of the tire. In addition, in the finished tire after vulcanization, the tire cord and rubber (eg, tread, etc.) are bonded together to maintain excellent adhesion.

Meanwhile, the tire cord of the embodiment may include a rubber coating layer formed on the adhesive layer.

In this case, the rubber coating layer may be formed by applying a rubber coating solution to the adhesive layer, and may have a thin rubber coating layer that is difficult to achieve through a rolling process using solid rubber, and the thickness of the rubber coating layer is thin. Depending on the load, the tire cord including the same and the tire including the tire cord may contribute to weight reduction.

Specifically, the rubber coating layer may be formed of an elastic polymer composition including synthetic rubber or natural rubber and a rubber coating solution including a solvent, and the elastic polymer composition may include an elastic polymer and additives.

The elastic polymer composition is, for example, natural rubber (NR), styrene butadiene rubber (SBR), butadiene rubber (BR), chloroprene rubber (CR) and isobutylene rubber (IBR), isoprene rubber (IR), nitrile rubber ( NBR), butyl rubber, and at least one elastomer selected from neoprene rubber may be included.

In addition, the additive may include, for example, carbon black, para-oil, zinc oxide, stearic acid, an antioxidant, sulfur, a vulcanization accelerator, an activator, an adhesive, an adhesive, and the like.

The solvent is not particularly limited in its type as long as it is a material capable of dissolving the elastic polymer, and may include, for example, at least one selected from toluene, naphtha, methanol, xylene, and tetrahydrofuran.

On the other hand, the rubber coating solution is based on the total weight of the rubber coating solution, 10 to 30% by weight of the elastic polymer composition; and 70 to 90% by weight of a solvent.

If the concentration of the elastomeric composition in the rubber coating solution is less than 10% by weight, the thickness of the rubber coating layer may become thin, so that adhesion and adhesion may not be properly expressed, and accordingly, the manufacturing characteristics of the tire may be deteriorated and problems of tire failure may occur during driving.

On the other hand, when the concentration of the elastomeric composition in the rubber coating solution exceeds 30% by weight, the stirrability of the adhesive solution is lowered due to the increase in viscosity and the dispersibility of the rubber coating solution is lowered. may cause problems.

On the other hand, the application amount per unit area of the rubber coating layer to the adhesive layer may be 75 to 300 g/m ² . When the application amount per unit area of the rubber coating layer to the adhesive layer is adjusted in the above range, the thickness is thin and excellent for rubber It is possible to provide a tire cord having excellent adhesion and excellent durability. Specifically, the lower limit of the application amount per unit area of the rubber coating layer to the adhesive layer is, for example, 80 g/m ² or more, 85 g/m ² or more, 90 g/m ² or more, 95 g/m ² or more, 100 g /m ² or more, 105 g/m ² or more, 110 g/m ² or more, 115 g/m ² or more, 120 g/m ² or more, 125 g/m ² or more, 130 g/m ² or more, 135 g/m 2 or more m ² or more, 140 g/m ² or more, 145 g/m ² or more, 150 g/m ² or more, 155 g/m ² or more, 160 g/m ² or more, 165 g/m ² or more, 170 g/m ² or more, 175 g/m ² or more, 180 g/m ² or more, 185 g/m ² or more, 190 g/m ² or more, 195 g/m ² or more, or 200 g/m ^{2 or} more. And, the upper limit of the application amount of the rubber coating layer is, for example, 290 g/m ² or less, 280 g/m ² or less, 270 g/m ² or less, 260 g/m ² or less, 250 g/m ² or less, 240 g/m ² or less, 230 g/m ² or less, 220 g/m ² or less, 210 g/m ² or less, 200 g/m ² or less, 190 g/m ² or less, 180 g/m ² or less, 170 g /m ² or less or 160 g/m ² or less.

When the amount of rubber applied per area of the rubber coating layer to the adhesive layer is less than the above range, there may be problems such as voids on the rubber surface or deterioration of the quality of the tire when the tire is manufactured using the tire cord. In addition, when the application amount exceeds the above range, the tire weight increases and the rolling resistance (R/R) increases. Accordingly, not only the fuel efficiency of the vehicle is lowered, but also the carbon dioxide emission may be increased.

Meanwhile, the rubber coating layer may have a thickness of 0.01 to 0.20 mm, or 0.02 to 0.20 mm, or 0.04 to 0.10 mm.

Conventional tire cords generally have a thickness of 1 mm or more, and a thickness of at least 0.8 mm or more, since a rubber layer is formed by rolling a rubber substrate on a fiber substrate.

On the other hand, since the rubber coating layer of the embodiment is formed by the rubber coating solution, it may have a thin thickness of 0.2 mm or less. Accordingly, the overall thickness of the tire cord may be reduced, and further, the thickness of the tire including the tire cord may be reduced.

When the thickness of the rubber coating layer is less than 0.01 mm, the rubber coating layer does not have sufficient adhesiveness and adhesive force, so that when the tire cord is applied to a tire, tire manufacturing characteristics may deteriorate, and durability of the tire may become difficult, furthermore, the tire defects may occur.

Also, when the thickness of the rubber coating layer exceeds 0.20 mm, the thickness of the tire cord may be increased to increase the thickness of the tire. In particular, bubbles are generated in the rubber coating layer in the process of solvent volatilization, making it difficult for the tire cord to have a uniform thickness. When this is applied to a tire, air pockets are generated in the tire, resulting in deterioration of tire quality and defective rate. this can be higher In addition, there is a disadvantage that the coating operation must be performed several times to form a thick rubber coating layer, which is inefficient in the process, and may result in deterioration of tire quality and defective rate.

Meanwhile, the tire cord may have a breaking strength of 2.0 to 15.0 g/d, or 8.0 to 13.0 g/d according to the standard test method of ASTM D885.

In addition, the tire cord may have an elongation at break of 10 to 30%, or 20 to 25% according to the standard test method of ASTM D885.

In addition, the tire cord may have an adhesive strength of 10 kgf or more, or 15 kgf or more when evaluating adhesive strength according to the ASTM D4393 standard test method.

In one example, the tire cord may have a one-ply structure. That is, the tire cord may be a tire cord manufactured by twisting one strand of the aforementioned yarn. If it has a one-ply structure, it is advantageous for securing a thin thickness of the tire cord and reducing the weight. In addition, it is advantageous to satisfy the aforementioned density and number of warp and weft yarns.

In another example related to the present application, the present application relates to a method of manufacturing a tire cord.

Specifically, according to another embodiment of the invention, by using a warp containing at least one of polyester including nylon, rayon, aramid and PET, the density between the warps is 65% or more or the number of warps per unit length (n/inch) ) preparing 35 or more woven fiber substrates; forming an adhesive layer on the fiber substrate; and applying a rubber coating solution on the adhesive layer and heat-treating it to form a rubber coating layer, wherein the rubber coating layer includes synthetic rubber or natural rubber, and the application amount per unit area of the rubber coating layer to the adhesive layer is 75 to A method of making a tire cord, which is 300 g/m ^{2 , may be provided.}

The content related to the fiber base includes the content described above with respect to the embodiment.

On the other hand, before the step of preparing the fiber base using the warp, it may further include the step of imparting twist to the warp including at least one of polyester including nylon, rayon, aramid and PET.

The degree of twist is based on the number of twists per 1 m, and the twist can be given from 0 to a maximum of 250 TPM.

As described above, with respect to the twisting of the fibers, the manufacturing method of the present application may be to prepare a one-ply structure by twisting one strand of the yarn.

Meanwhile, the adhesive layer may be formed on the fiber substrate, and the adhesive layer may be formed by an adhesive coating solution containing resorcinol-formaldehyde-latex (RFL) and a solvent. In this case, the step of forming the adhesive layer may include applying an adhesive coating solution on the fiber substrate and performing heat treatment.

The method for applying the adhesive coating solution on the fiber substrate is not particularly limited, and for example, the adhesive coating solution may be applied on the fiber substrate by dipping the fiber substrate in the adhesive coating solution. Alternatively, the immersion process may be performed by passing the fiber substrate through the adhesive coating solution. This dipping process may be performed in a dipping machine in which tension, dipping time and temperature can be controlled.

In addition, the adhesive coating solution may be applied on the fiber substrate by coating using a blade or a coater or spraying using a sprayer as well as an immersion process.

Meanwhile, the step of forming the adhesive layer may further include a step of applying an adhesive coating solution on the fiber substrate and heat-treating the adhesive coating solution at 130 to 250° C. for 80 to 120 seconds. In this case, the heat treatment may be performed in a heat treatment apparatus, and the resorcinol-formaldehyde-latex (RFL) may be cured and fixed by the heat treatment to complete the adhesive layer. The adhesive layer may be more stably formed by such heat treatment.

Meanwhile, after forming the adhesive layer, a rubber coating solution may be applied on the adhesive layer and heat-treated to form a rubber coating layer.

The rubber coating solution may include an elastomeric composition and a solvent, and the elastomeric composition may include an elastomeric polymer and an additive.

The elastic polymer composition is, for example, natural rubber (NR), styrene butadiene rubber (SBR), butadiene rubber (BR), chloroprene rubber (CR) and isobutylene rubber (IBR), isoprene rubber (IR), nitrile rubber ( NBR), butyl rubber, and at least one elastomer selected from neoprene rubber may be included.

In addition, the additive may include, for example, carbon black, para-oil, zinc oxide, stearic acid, an antioxidant, sulfur, a vulcanization accelerator, an activator, an adhesive, an adhesive, and the like.

The solvent is not particularly limited in its type as long as it is a material capable of dissolving the elastic polymer, and may include, for example, at least one selected from toluene, naphtha, methanol, xylene, and tetrahydrofuran.

On the other hand, the rubber coating solution is based on the total weight of the rubber coating solution, 10 to 30% by weight of the elastic polymer composition; and 70 to 90% by weight of a solvent.

If the concentration of the elastomeric composition in the rubber coating solution is less than 10% by weight, the thickness of the rubber coating layer may become thin, so that adhesion and adhesion may not be properly expressed, and accordingly, the manufacturing characteristics of the tire may be deteriorated and problems of tire failure may occur during driving.

On the other hand, when the concentration of the elastomeric composition in the rubber coating solution exceeds 30% by weight, the stirrability of the adhesive solution is lowered due to the increase in viscosity and the dispersibility of the rubber coating solution is lowered. may cause problems.

On the other hand, a method of applying the rubber coating solution on the adhesive layer is not particularly limited, and a known coating method may be applied.

For example, in order to form a rubber coating layer, a fiber base coated with an adhesive layer may be immersed in a rubber coating solution. A rubber coating solution may be applied on the adhesive layer by such immersion.

As a coating method, there are a gravure coating method, a micro gravure coating method, comma coating, etc., for example, rubber by comma coating using a comma coater. A coating solution may be applied on the adhesive layer. At this time, the coating may be made at a temperature condition of 65 to 100 ℃, this temperature corresponds to the lowest temperature at which the solvent can be volatilized.

On the other hand, after applying a rubber coating solution on the adhesive layer, the process may further include a heat treatment process.

In this case, the heat treatment may be performed in a heat treatment apparatus, and for the heat treatment, heat may be applied at a temperature of 50 to 160° C. for 30 to 150 seconds.

On the other hand, the application amount per unit area ^{of the rubber coating layer may be 75 to 300 g/m 2} , and by adjusting the application amount per unit area of the rubber coating layer to the adhesive layer in the above range, the rubber coating layer has excellent adhesion and durability This excellent tire cord can be manufactured. The specific application amount is as above-mentioned.

Meanwhile, the rubber coating layer may have a thickness of 0.01 to 0.20 mm, or 0.02 to 0.20 mm, or 0.04 to 0.10 mm. When the thickness of the rubber coating layer is less than 0.01 mm, the rubber coating layer does not have sufficient adhesiveness and adhesive force, so that tire manufacturing characteristics may be deteriorated, and further, defects may occur in the tire. In addition, when the thickness of the rubber coating layer exceeds 0.20 mm, the thickness of the tire cord may be increased to increase the thickness of the tire.

On the other hand, after the formation of the rubber coating layer, a slitting step may be optionally performed.

The method may further include cutting the tire cord manufactured in a plate shape as needed or suitable for the purpose of use. Such cutting is referred to as slitting. The slitting step may be omitted, and there is no particular limitation on the cutting or slitting method.

For example, slitting may be performed by cutting the tire cord using a conventional cutter knife or a heating knife.

Meanwhile, the tire cord manufactured through the manufacturing method may be wound on a winder.

In another example related to the present application, the present application relates to a tire.

Specifically, according to another embodiment of the present invention, a tire including the tire cord may be provided.

The tire cord may be applied to, for example, a cap ply of a tire, a belt, a carcass, etc., and the tire cord has excellent adhesion to rubber and may be easily attached to the rubber without a conventional rolling process.

When the tire cord is used as the cap ply, the rolling process can be omitted, thereby simplifying the manufacturing process of the tire, and also greatly increasing the adhesion of the cap ply, thereby reducing the air pocket when manufacturing the green tire. This can reduce the tire defect rate. In addition, since the rolling process is not performed, a thin and light tire can be manufactured.

According to the present invention, a tire cord having excellent durability while having a thin thickness can be provided.

Further, according to the present invention, a method for manufacturing a tire cord having excellent durability while having a thin thickness can be provided.

Also, according to the present invention, a tire including the tire cord may be provided.

The invention is described in more detail in the following examples. However, the following examples only illustrate the present invention, and the content of the present invention is not limited by the following examples.

Examples and Comparative Examples

Example 1

A fiber base (thickness: about 0.40 mm) was woven with a twist of 200 TPM to nylon having a total fineness of 630de, 58 warps (n/inch), and a warp density of 90%. At this time, the number of weft yarns (n/inch) was 8, and the weft density was 4.8%.

Thereafter, the fiber base is immersed in an adhesive coating solution containing 15% by weight of resorcinol-formaldehyde-latex (RFL) and 85% by weight of a solvent (water, HO), and then heat-treated at 150° C. for 100 seconds. An adhesive layer was formed.

Thereafter, using a comma coater, a rubber coating layer is applied on the adhesive layer at an application amount of 120 to 130 g/m ² per unit area, and the solvent is volatilized at a temperature of 70° C., and a rubber coating layer having a thickness of 0.04 to 0.05 mm is applied. A formed tire cord was prepared.

At this time, the rubber coating layer was formed by applying a rubber coating solution to the adhesive layer, and the rubber coating solution was 20-50 parts by weight of carbon black based on 100 parts by weight of styrene butadiene rubber (SBR) and natural rubber in a solvent in a weight ratio of 100 toluene, Para-oil 5-10 parts by weight, zinc oxide 2-8 parts by weight, stearic acid 2-8 parts by weight, antioxidant (RUBBER ANTIOXIDANTS, BHT) 1-5 parts by weight, sulfur 2-8 parts by weight and vulcanization accelerators, ZnBX) was prepared by dispersing an elastic polymer composition containing 1 to 3 parts by weight at a concentration of 20 to 40%.

Example 2

A fiber base was woven with a twist of 150 TPM to nylon having a total fineness of 1260 de, and a warp count (n/inch) of 42 and a warp density of 84%.

Thereafter, the fiber base is immersed in an adhesive coating solution containing 15% by weight of resorcinol-formaldehyde-latex (RFL) and 85% by weight of a solvent (water, H2O), and then heat-treated at 150° C. for 100 seconds. An adhesive layer was formed.

Thereafter, using a comma coater, a rubber coating layer is applied on the adhesive layer at an application amount of 130 to 140 g/m ² per unit area, and the solvent is volatilized at a temperature of 70° C., a rubber coating layer having a thickness of 0.06 to 0.07 mm A formed tire cord was prepared.

In this case, the same rubber coating solution as in Example 1 was used for the rubber coating layer.

Example 3

A fiber base was woven with a twist of 150 TPM to PET having a total fineness of 800 de, 50 warps (n/inch), and a warp density of 71%.

Thereafter, the fiber base is immersed in an adhesive coating solution containing 15% by weight of resorcinol-formaldehyde-latex (RFL) and 85% by weight of a solvent (water, HO), and then heat-treated at 150° C. for 100 seconds. An adhesive layer was formed.

Then, using a comma coater, a rubber coating layer is applied on the adhesive layer at an application amount of 150 to 160 g/m ² per unit area, and the solvent is volatilized at a temperature of 70° C., so that a rubber coating layer having a thickness of 0.07 to 0.08 mm A formed tire cord was prepared.

In this case, the rubber coating layer was formed by applying a rubber coating solution to the adhesive layer, and a tire cord was manufactured in the same manner as in Example 1.

Comparative Example 1

In the same manner as in Example 1, except that the nylon having a total fineness of 630de was given a twist of 200 TPM, the number of warps (n/inch) was 34, and the warp density was 53%, except that a fiber base was used. Cords and tires were made.

Comparative Example 2

In the same manner as in Example 1, except that the nylon having a total fineness of 1260de is given a twist of 150TPM, the number of warps (n/inch) is 30, and a fiber base having a warp density of 60% is used. Cords and tires were made.

Comparative Example 3

In the same manner as in Example 1, except that a fiber base having a twist of 150 TPM and a warp count (n/inch) of 34 and a warp density of 47% was used to PET having a total fineness of 800de. Cords and tires were made.

Comparative Example 4

Using a comma coater, apply a rubber coating layer on the adhesive layer at an application amount of 45 to 50 g/m ² per unit area and volatilize the solvent at a temperature of 70° C. to form a rubber coating layer with a thickness of 0.01 to 0.02 mm A tire cord was manufactured in the same manner as in Example 1 except for the above.

Comparative Example 5

Using a comma coater, apply a rubber coating layer on the adhesive layer at an application amount of 65 to 70 g/m ² per unit area and volatilize the solvent at a temperature of 70° C. to form a rubber coating layer with a thickness of 0.02 mm A tire cord was manufactured in the same manner as in Example 2, except that.

Comparative Example 6

Using a comma coater, apply a rubber coating layer on the adhesive layer at an application amount of 65 to 70 g/m ² per unit area and volatilize the solvent at a temperature of 70° C. to form a rubber coating layer with a thickness of 0.02 mm A tire cord was manufactured in the same manner as in Example 3, except that.

Experimental example

Experimental Example 1: Measurement of breaking strength and elongation at break

According to ASTM D885 test method, using an Instron testing machine (Instron Engineering Corp., Canton, Mass), the tire was subjected to a tensile speed of 300 m/min for 10 samples of 250 mm (width 10 mm x length 250 mm). The strength at break and the elongation at break of the cord were measured, respectively.

Then, the cutting strength (g/d) of each sample was obtained by dividing the cutting strength of each sample by the total fineness of the tire cord. Then, by calculating the average values of the breaking strength and elongation at break of the ten samples, respectively, the breaking strength and elongation at break of the tire cord having the rubber coating layer were obtained. In addition, the elongation under the load of 4.5 kgf and the elongation at the load of 6.8 kgf were measured, respectively.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Number of slopes per unit area
(n/inch) 58 42 50 34 30 34 58 42 50 Gradient Density (%) 90 84 71 53 60 47 90 84 71 coating layer coating
(g/m ² ) 120 ~ 130 130 to 140 150 to 160 120 ~ 130 120 ~ 130 120 ~ 130 45 to 50 65 to 70 65 to 70 Strong (10mm, kgf) 144.77 209.14 165.66 82.41 144.28 110.75 138.47 198.21 162.34 Cutting strength (g/d) 10.0 9.2 8.6 8.6 8.9 8.5 8.6 8.9 8.5 Elongation at break (%) 23.55 22.6 10.7 12.5 14.2 8.9 22.95 21.2 9.9 Elongation at 4.5 kgf (%) 0.67 0.62 0.39 0.86 0.73 0.46 0.62 0.57 0.34 Elongation at 6.8 kgf (%) 0.96 0.85 0.49 1.24 0.91 0.58 0.88 0.80 0.42

According to Table 1, it was confirmed that, when the tire cord according to the embodiment of the present invention was used, superior properties were exhibited in strength, breaking strength and elongation at break compared to the comparative example.

Experimental Example 2: Adhesion Measurement

According to the test method of ASTM D4393, the adhesive peel strength of the tire cords prepared in Examples and Comparative Examples for the carcass layer of the tire was measured.

Specifically, a sample was prepared by laminating a rubber sheet with a thickness of 0.6 mm, cord paper, a rubber sheet with a thickness of 0.6 mm, cord paper, and a rubber sheet with a thickness of 0.6 mm in order, and then 15 at 170° C. under a pressure of 60 kg/cm2. Vulcanized for minutes. Next, the vulcanized sample was cut to prepare a specimen having a width of 1 inch. For the thus-prepared specimen, a peel test was performed at 25° C. at a rate of 125 mm/min using a universal material tester (Instron) to measure the adhesion of the tire cord to the carcass layer. At this time, the average value of the load generated during peeling was calculated as the adhesive force.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Adhesion (kgf) 18.2 17.2 22.6 13.4 14.8 16.1 10.1 9.7 12.6

According to Table 2, when the tire cord according to the embodiment of the present invention was used, it was confirmed that the tire cord had superior adhesion to rubber as compared to the tire cord of the comparative example.

Claims (17)

Using a warp containing at least one of polyester including nylon, rayon, aramid and PET, a fiber base woven with a density between warps of 65% or more or the number of warps per unit length (n/inch) of 35 or more; and
an adhesive layer formed on the fiber substrate; and
Including; a rubber coating layer formed on the adhesive layer;
The rubber coating layer includes synthetic rubber or natural rubber,
The application amount per unit area of the rubber coating layer to the adhesive layer is 75 to 300 g / m ² ,
tire code.
The method of claim 1,
The fiber base is a tire cord woven with a density of 65% or more between warps and 35 or more warps per unit length (n/inch).
According to claim 1,
wherein the fibrous substrate has a thickness of 0.10 to 0.60 mm.
According to claim 1,
The rubber coating layer has a thickness of 0.01 to 0.20 mm, tire cord.
According to claim 1,
The rubber coating layer may include: 10 to 30% by weight of an elastic polymer composition comprising synthetic rubber or natural rubber; And a tire cord formed by applying a rubber coating solution containing 70 to 90% by weight of a solvent to the adhesive layer.
According to claim 1,
wherein the adhesive layer comprises resorcinol-formaldehyde-latex (RFL).
According to claim 1,
A tire cord having a breaking strength of 2.0 to 15.0 g/d according to the standard test method of ASTM D885.
According to claim 1,
A tire cord having an elongation at break of 10 to 30% according to the standard test method of ASTM D885.
According to claim 1,
A tire cord having an adhesive force of 10 kgf or more when evaluating adhesion according to ASTM D4393 standard test method.
Using a warp containing at least one of polyester including nylon, rayon, aramid and PET, prepare a woven fiber base with a density of 65% or more between warps or 35 or more warps per unit length (n/inch) to do;
forming an adhesive layer on the fiber substrate; and
Including; applying a rubber coating solution on the adhesive layer and heat-treating to form a rubber coating layer;
The rubber coating layer includes synthetic rubber or natural rubber,
The application amount per unit area of the rubber coating layer to the adhesive layer is 75 to 300 g / m ² ,
A method of manufacturing a tire cord.
The method for manufacturing a tire cord according to claim 10, wherein the inter-warp density is 65% or more, and the fiber base is prepared in an amount of 35 or more warps per unit length (n/inch).
11. The method of claim 10,
The fiber substrate has a thickness of 0.10 to 0.60 mm, a method of manufacturing a tire cord.
11. The method of claim 10,
The rubber coating layer has a thickness of 0.01 to 0.20 mm, a method of manufacturing a tire cord.
11. The method of claim 10,
The rubber coating solution may include 10 to 30% by weight of an elastic polymer composition comprising synthetic rubber or natural rubber; and 70 to 90% by weight of a solvent,
A method of manufacturing a tire cord.
11. The method of claim 10,
The method for manufacturing a tire cord, wherein the adhesive layer comprises resorcinol-formaldehyde-latex (RFL).
11. The method of claim 10,
and imparting twist to a warp comprising at least one of polyester including nylon, rayon, aramid and PET.
A tire comprising a tire cord according to any one of claims 1 to 9.