JP2007169833A - Polyester tire cap ply cord and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester tire cap ply cord which has high elastic modulus and remarkably improved fatigue resistance and adhesiveness to rubbers, and to provide a method for producing the same. <P>SOLUTION: This method for producing the polyester tire cap ply cord includes treating a polyester fiber material in a first treating bath containing (A) a polyepoxide compound, (B) a blocked polyisocyanate compound and (C) a rubber latex and having a solid content weight ratio (A)/[(A)+(B)] of 0.05 to 0.9 and solid content weight ratio (C)/[(A)+(B)] of 0.5 to 15 as a treating liquid to impart adhesiveness to rubbers to the polyester fiber material, treating the polyester fiber material in the second treating bath containing a resorcinol-formalin-rubber latex, and then thermally treating the treated polyester fiber material under a normalizing tension adjusted to ≥0.2 cN/dtex. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a polyester tire cap ply cord having a high elastic modulus and having significantly improved adhesion to rubber and fatigue resistance, and a method for producing the same.
The polyester tire cap ply cord obtained by the present invention is suitable for a cap cord used for a tire cord, particularly a belt outer layer portion of a radial tire.

Polyester fiber typified by polyethylene terephthalate has excellent mechanical properties, dimensional stability, and durability, and is widely used in industrial material applications, especially rubber reinforcement applications such as tire cords, V belts, conveyor belts, hoses, etc. ing.
For tire cord applications, properties such as high strength, high elastic modulus, low shrinkage, adhesion, and fatigue resistance are required. Polyethylene terephthalate fibers are used in the radial tire carcass ply cord due to their superior performance and cost. On the other hand, while the needs for high-speed durability of tires are increasing, cap ply cords are used for the outer layer of the belt, and heat resistance adhesion is particularly required, so nylon with excellent adhesion 66 is the mainstream.

  Nylon 66 fiber basically has a low elastic modulus, so it has a low effect of suppressing the protruding property of the belt layer end during high speed running. For this reason, in tires that emphasize high speed durability, the number of cords to be driven is increased. Is necessary, and there is a drawback in that the weight of the tire increases. On the other hand, it has been proposed to use polyethylene terephthalate having a higher elastic modulus, but it has a problem of low heat-resistant adhesion, and is practically unusable (see, for example, Patent Document 1).

The cause of the decrease in strength and adhesion of polyester fibers in rubber compounds is said to be due to the deterioration of the rubber compound due to the action of amines and moisture. Proposals have been made.
For example, a method has been proposed in which a polyester fiber having a carboxyl end group amount of 10 μeq / g or less is subjected to an epoxy compound treatment, a polyisocyanate compound treatment and an RFL treatment (see Patent Document 2), but the polyisocyanate treatment is an organic solvent system. It is not practical because it is done.

  Many other proposals have been made for polyester fiber materials, such as a method of using a treatment liquid containing an epoxy compound and an isocyanate compound for the problem of adhesiveness of the polyester fiber material to rubber. When is added to the composition of the adhesive, there is a problem that the adhesive resin layer of the fiber material after the treatment becomes hard, the fatigue resistance is lowered, and the high-speed durability of the tire is deteriorated.

About the method of suppressing the hardness of the fiber material after a process, and fatigue resistance, mix | blending adhesive components, such as an epoxy, isocyanate, and resorcin-formalin-latex, with a specific weight ratio is proposed ( (See Patent Document 3).
However, the mechanical properties suitable for the cap ply cord application are not sufficiently considered, and a tire in which a polyester fiber material is applied to a belt reinforcing layer still has a high-speed durability than a tire in which a nylon 66 fiber is applied to the belt reinforcing layer. It is inferior and is not sufficient for cap ply cord applications.

JP 59-124407 A JP-A 51-70394 JP-A-54-73994

  The present invention has been made against the background of the above circumstances, and provides a polyester tire cap ply cord having a high elastic modulus, sufficient adhesion to rubber, and excellent fatigue resistance, and a method for producing the same. For the purpose.

As a result of intensive studies in order to solve the above problems, the present inventors have finally completed the present invention. That is, the present invention has the following configuration.
1. When imparting adhesiveness to rubber to the polyester fiber material, the treatment liquid contains (A) a polyepoxide compound, (B) a blocked polyisocyanate compound, and (C) a rubber latex, and the solid content weight ratio of each component is In the first treatment bath in which (A) / [(A) + (B)] is 0.05 to 0.9 and (C) / [(A) + (B)] is 0.5 to 15. The polyester tire cap ply cord is characterized in that the polyester tire cap ply cord is treated with a second treatment bath containing resorcin-formalin-rubber latex and then subjected to heat treatment under a normalizing tension adjusted to 0.2 cN / dtex or more. Production method.
2. 2. The method for producing a polyester tire cap ply cord according to 1 above, wherein the normalizing tension is 0.3 cN / dtex or more.
3. 2. The method for producing a polyester tire cap ply cord according to 1 above, wherein the normalizing tension is 0.4 cN / dtex or more.
4). The solid content weight ratio of each component of the first treatment bath is 0.1 to 0.5 for (A) / [(A) + (B)], and (C) / [(A) + (B)]. It is 1-10, The manufacturing method of the polyester tire cap ply cord in any one of said 1-3 characterized by the above-mentioned.
5. (A) The polyepoxide compound contained in the first treatment liquid is a polyglycidyl ether compound of a polyhydric alcohol, (B) the blocked polyisocyanate compound is a blocked aromatic polyisocyanate compound, and (C) the rubber latex is vinyl. 5. The method for producing a polyester tire cap ply cord according to any one of the above 1 to 4, which is a pyridine-styrene-butadiene-terpolymer latex.
6). Any of 1 to 5 above, wherein the polyester fiber material is a cord obtained by twisting a polyethylene terephthalate fiber treated with an epoxy compound having two or more epoxy groups in a spinning, drawing or post-treatment step, and a woven fabric obtained by weaving the cord. The manufacturing method of the polyester tire cap ply cord of description.
7). The strength of the treated cord is 4.5 cN / dtex or more, the elongation at the time of 2.0 cN / dtex is 5.0% or less, and the rubber coverage after the initial vulcanization in the peel adhesion test at room temperature is 90%. The polyester tire cap ply cord having a rubber coverage of 80% or more after overvulcanization.
8). Rubber after initial vulcanization in a heat peel adhesion test in a 150 ° C. atmosphere with a treated cord strength of 4.5 cN / dtex or higher and an elongation at a load of 2.0 cN / dtex of 5.0% or lower A polyester tire cap ply cord having a coverage of 90% or more and a rubber coverage after overvulcanization of 80% or more.
9. The polyester tire cap ply cord according to 7 or 8 above, wherein the treated cord has an elongation at a load of 2.0 cN / dtex of 4.0% or less.
10. The polyester tire cap ply cord according to 7 or 8 above, wherein the elongation of the treated cord at a load of 2.0 cN / dtex is 3.5% or less.
11. The polyester tire cap ply cord according to any one of 7 to 10 above, wherein the twist coefficient K of the treatment cord represented by K = T√D is 2500 or less.
Here, T is the number of twists of the cord (times / 10 cm), and D is the standard fineness (dtex) of the cord.

  According to the present invention, it is possible to provide a polyester tire cap ply cord and a method for producing the same, which have a high elastic modulus and have significantly improved adhesion to rubber and fatigue resistance.

Hereinafter, the present invention will be described in detail.
The polyester fiber material constituting the polyester cord of the present invention is a cord (raw cord) obtained by twisting drawn yarn (raw yarn) obtained by melt spinning polyethylene terephthalate or polyethylene terephthalate copolymerized with a small amount of a third component, or It is a woven fabric.

The polyethylene terephthalate raw yarn is made of unstretched yarn or polyester fiber surface-activated with an epoxy compound or isocyanate compound at the stage of drawn yarn, as shown in Japanese Patent Publication No. 47-49768. In particular, it is preferable that the polyethylene terephthalate raw yarn is treated with an epoxy compound having two or more epoxy groups in the spinning, drawing or post-treatment step. Preferable examples of the epoxy compound include polyglycidyl ether compounds of aliphatic polyhydric alcohols such as glycerol / polyglycidyl ether, diglycerol / polyglycidyl ether, polyglycerol / polyglycidyl ether, and sorbitol / polyglycidyl ether. Furthermore, it is preferable that the raw yarn treated with the epoxy compound and the curing agent is heat-treated at a temperature of 40 ° C. to 80 ° C. for 24 hours to 240 hours.

The strength of the treatment cord subjected to a treatment for imparting adhesiveness to rubber (hereinafter referred to as a dip treatment) is 4.5 cN / dtex or more, preferably 5.0 cN / dtex or more. This is indispensable as the basic performance of the tire cord, and if it is less than this, it is not suitable for use as a tire cord. Here, the cord strength is a value obtained by dividing the cord strength by a reference fineness in cord constitution (for example, 2200 dtex if two original yarns of 1100 dtex are twisted together).

As an evaluation measure of the elastic modulus, an elongation at a load of 2.0 cN / dtex (hereinafter referred to as intermediate elongation) is used, and the intermediate elongation is 5.0% or less, preferably 4.0% or less, more preferably 3.5% or less. It is a well-known fact that, in the tire cap ply cord, by using a cord having a high elastic modulus, reduction of tire road noise and improvement of high-speed performance can be obtained. If the intermediate elongation is higher than 5.0%, it is not suitable as a tire cap ply cord.

The intermediate elongation of the treatment cord largely depends on the tension of the heat treatment zone (normalizing zone) at the final stage in the dip treatment, and is 0.2 cN / dtex or more, preferably 0.3 cN / dtex or more, and more preferably 0.8. 4 cN / dtex or more. If the normalizing tension is less than 0.2 cN / dtex, the intended high elastic modulus cord cannot be obtained.

Further, the factor contributing to the intermediate elongation includes the number of twists of the cord, and the twist coefficient K of the treated cord represented by K = T√D is preferably 2500 or less. In this equation, T is the number of twists of the cord (times / 10 cm), and D is the standard fineness (dtex) of the cord. When the twisting coefficient K exceeds 2500, not only is it difficult to obtain a high elastic modulus cord, but also the strength is lowered, making it unsuitable as a tire cap ply cord.

As a measure for evaluating adhesiveness, rubber coverage in a rubber-cord peel adhesion test during overvulcanization and / or heat is used. In general, when a polyester tire cord is exposed to a high temperature in rubber for a long time, the adhesive strength is reduced. This phenomenon is thought to be due to deterioration of rubber and adhesive (dip resin) and fibers and their interfaces. In the conventional polyester tire cord, since the rubber hardly adheres to the cord after the adhesion failure, the failure has occurred at the fiber and / or adhesive and their interface, which is no longer than the cohesive failure of the rubber. On the other hand, in the nylon 66 excellent in heat-resistant adhesiveness, the cord after adhesion failure is almost covered with rubber, and the fracture site is shifted to the rubber side, not the layer from the fiber to the adhesive. From these viewpoints, it is possible to determine the superiority or inferiority of the heat-resistant adhesiveness by evaluating the rubber coverage. For tire cap ply use, it is necessary that the rubber coverage after initial vulcanization is 90% or higher and the rubber coverage after overvulcanization is 80% or higher in both normal temperature atmosphere and 150 ° C high temperature atmosphere. It is. Below this, it is not suitable as a tire cap ply cord.

The polyepoxide compound used in the present invention is a compound containing 0.2 g equivalent or more per 100 g of the epoxide compound per molecule, such as ethylene glycol, glycerol, sorbitol, pentaerythritol, polyethylene glycol, etc. Reaction products of polyhydric alcohols with halogen-containing epoxides such as epichlorohydrin, polyhydric phenols such as resorcin, bis (4-hydroxyphenyl) dimethylmethane, phenol, formaldehyde resin, resorcin-formaldehyde resin, and the halogen-containing epoxide Polyepoxide compounds obtained by curing unsaturated bonds with periacetic acid, peracetic acid, hydrogen peroxide, etc., ie 3,4-epoxycyclohexene epoxide, 3,4-epoxycyclo Examples include hexylmethyl, 3,4-epoxycyclohexenecarboxylate, and bis (3,4-epoxy-6methyl-cyclohexylmethyl) adipate. Among these, a reactive product of polyhydric alcohol and epichlorohydrin, that is, a polyglycidyl ether compound of polyhydric alcohol is preferable because it exhibits excellent performance.

Such a polyepoxide compound is usually preferably used as an emulsion or solution. In order to obtain an emulsified liquid or solution, for example, such a polyepoxide compound as it is or in a small amount of a solvent as necessary is emulsified or dissolved using a known emulsifier such as sodium alkylbenzene sulfonate.

Next, the blocked polyisocyanate compound used in the present invention is an addition reaction product of a polyisocyanate and a blocking agent, and the block component is released by heating to produce an active polyisocyanate.

Examples of the polyisocyanate compound include polyisocyanates such as tolylene diisocyanate, metaphenylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, polymethylene phenyl isocyanate, triphenylmethane triisocyanate, or these polyisocyanates, trimethylolpropane, pentaerythritol and the like. The terminal NCO group-containing polyalkylene glycol adduct polyisocyanate obtained by reacting a compound having 2 or more active hydrogen atoms with a molar ratio of NCO / OH> 1. In particular, tolylene diisocyanate, diphenylmethane diisocyanate, and hexamethylene diisocyanate polyisocyanate are preferable, and a diphenylmethane diisocyanate polyisocyanate (a bifunctional diphenylmethane diisocyanate may be mixed) mixture exhibits excellent performance.

Examples of the blocking agent include phenols such as phenol, thiophenol, cresol, and resorcinol; tertiary alcohols such as 1-butanol and 1-pentanol; aromatic secondary amines such as diphenylamine and xylidine; There are imides such as acid imides, caprolactams, and acidic sodium sulfite.

Examples of the rubber latex used in the present invention include natural rubber latex, styrene-butadiene-copolymer latex, vinylpyridine-styrene-butadiene-terpolymer latex, nitrile rubber latex, neoprene latex, and the like. use. Among these, the best performance is obtained when the vinylpyridine-styrene-butadiene copolymer latex is used alone or in combination with more than half amount.

The first treatment bath contains (A) a polyepoxide compound, (B) a blocked polyisocyanate compound, and (C) a rubber latex, and the blended solids weight ratio of each component (A), (B), (C) is ( A) / [(A) + (B)] should be 0.05 to 0.9, and (C) / [(A) + (B)] should be 0.5 to 15. . Particularly, it is blended so that (A) / [(A) + (B)] is in the range of 0.1 to 0.5 and (C) / [(A) + (B)] is in the range of 1 to 10. preferable.
Here, if (A) / [(A) + (B)] deviates from the above, the rubber adhesion rate of the polyester fiber material is deteriorated and the adhesiveness is lowered, and (C) / [(A) + (B)]. When the value is smaller than the above range, the treated polyester fiber material becomes hard, and the fatigue resistance is lowered.

A suitable amount of the dispersant for using the first treatment bath component as a water dispersant, that is, a surfactant is 0 to 15% by weight, preferably 10% by weight or less, based on the total solid content of the first treatment bath. If the above range is exceeded, the adhesive strength tends to be slightly reduced.

The second treatment bath of the present invention is a composition containing resilcine-formalin-rubber latex, but the resorcin-formalin-rubber latex used here is usually called RFL, and the molar ratio of resorcin to formaldehyde Is preferably in the range of 1: 0.5 to 1: 3, or the mixing ratio of resorcin-formalin to rubber latex in the mixing ratio of 1: 3 to 1:20. If it is out of the above range, the adhesive performance of the treated fiber material tends to be lowered. Further, the rubber latex used here is the same as that used in the first treatment bath, and among them, vinylpyridine-styrene-butadiene-terpolymer latex is used alone, or a combination of more than half amount shows excellent performance.
In addition to the resorcin-formalin-rubber latex, an adhesion aid, a treatment bath stabilizer, and the like may be added to the second treatment bath, but the total weight of the second treatment bath composition is ½ weight or more. The resorcin-formalin-rubber latex is preferably included.

In order to attach the first treatment bath and the second treatment bath to the polyester fiber material, any method such as application by contact with a roller or spraying from a nozzle or immersion in a liquid bath can be employed. The solid content adhesion to the polyester fiber material is 0.1 to 10% by weight, preferably 0.5 to 5% by weight as the first treatment bath composition, 0.5 to 10% by weight as the second treatment bath composition, It is preferable to deposit 1 to 5% by weight. In order to suppress the amount of solid content adhering to the fiber material, means such as squeezing with a pressure roller, scraping with a scrubber, blowing with air blowing, suction, absorption, and tapping with a beater may be used.

In the present invention, the polyester fiber material is treated in the first treatment bath, dried at a temperature of 60 ° C. to 200 ° C. for 30 to 240 seconds, then heat treated at 180 ° C. to 250 ° C. for 30 to 200 seconds, and then second. It is treated in a treatment bath, dried at a temperature of 60 ° C. to 200 ° C. for 30 to 240 seconds, and then heat treated at 180 ° C. to 250 ° C. for 30 to 200 seconds. If the drying and heat treatment temperature is too low, the adhesion to the rubber will be insufficient. On the other hand, if the drying and heat treatment temperature is too high, the polyester fiber will melt, fuse, or cause a significant decrease in strength, making it unusable. .

The polyester cord of the present invention thus obtained has a high elastic modulus suitable for tire cap ply applications, and has a high rubber coverage when exposed to high temperatures in rubber for a long time, and exhibits extremely high adhesion. It is a revolutionary product that is flexible and has low bending hardness, good moldability and improved fatigue resistance.

EXAMPLES Next, although this invention is demonstrated concretely using an Example and a comparative example, this invention is not limited to this. Each physical property value is measured by the following method.
(Strong elongation)
In accordance with JIS-L1017 8.5 (2002), after standing in a temperature-controlled room at 20 ° C. and 65% RH for 24 hours or more, the tensile strength was measured with a tensile tester.
(Fineness)
In accordance with JIS-L1017 8.3 (2002), the fineness was measured after being left for 24 hours or longer in a temperature-controlled room at 20 ° C. and 65% RH.
(Pull-out adhesion)
The T test (Method A) in JIS-L1017 Annex 1 3.1 (2002) was evaluated by a modified H test.
Rubber for tires (general-purpose unvulcanized rubber, such as natural rubber, SBR rubber, polyisoprene rubber, polybutadiene rubber, general-purpose vulcanizing compound such as vulcanizing agent, vulcanization accelerator, carbon black, anti-aging 1 cm length embedded in rubber compounding agent, filler, etc.), vulcanized at 140 ° C. for 40 minutes (initial) or 170 ° C. for 60 minutes (overvulcanized), then corded from rubber at room temperature The force required to pull out the wire at 300 mm / min is expressed in N / cm.
(Peeling adhesion)
JIS-K6256 5. (1999) “Cloth and vulcanized rubber peel test” was measured by an improved method. A test piece was prepared by laminating the processing cord and tire rubber shown in FIG. 1 (rubber thickness 0.7 mm, width 25 mm, number of cords to be corded 33 between the cord and cord), and 140 minutes at 140 ° C. (Initial) or after vulcanization at 170 ° C. for 60 minutes (over vulcanization), the upper and lower parts (parts a and b in FIG. 1) of the test piece are pinched at room temperature and peeled off at 50 mm / min with a tensile tester. Is the force required for N / 25 mm. Furthermore, the test piece was heat-treated in an oven at 150 ° C. for 10 minutes, and the peel strength was measured in the same manner (when hot).
After the test, the rubber coverage of the cord on the peeled surface was visually evaluated. When the cord was completely covered with rubber, the coverage was 100%, and when no rubber was attached at all, the cord was 0%.
(Disk fatigue resistance)
The disk fatigue strength (Goodrich method) of JIS-L1017 Annex 1 2.2.2 (2002) was evaluated. Two treatment cords are embedded in rubber and vulcanized at 140 ° C for 40 minutes to produce a rubber composite. The test piece was subjected to a deformation of 12.5% compression and 6.3% elongation for 1 cycle at 2600 cycles / min for 72 hours, and then the cord was taken out from the rubber and the fracture strength after fatigue was measured. It is represented by the retention before and after the test.
(Cord hardness)
It evaluated by the Gurley method of JIS-L1096 8.20.1 A method (1999). A load of 25 g is attached to a position 5.08 cm below the pendulum fulcrum of the Gurley Stephine Tester. A sample with a cord length of 3.81 cm is attached to the chuck of the movable arm (the test length between the chuck and the free end of the pendulum is 2.54 cm), the movable arm is operated, and the scale at the moment when the sample leaves the free end of the pendulum RG was used, and the cord hardness was obtained from the following equation.
Cord hardness (mN) = RG x 0.969 / cord gauge (cm)

Example 1
A polyethylene terephthalate chip having an intrinsic viscosity of 0.95 dl / g was melted and discharged from a spinneret having a pore number of 190 at a spinning temperature of 300 ° C., passed through a heating region of 320 ° C., and then cooled and solidified with cooling air of 20 ° C., The film was taken up at a spinning speed of 550 m / min, and subsequently drawn at a draw ratio of 5.8 times, provided with sorbitol polyglycidyl ether as an epoxy compound, relaxed by 3.0%, and wound up. Two strands of polyethylene terephthalate of 1100 dtex and 190 filaments thus obtained (intrinsic viscosity 0.88 dl / g, strength 8.3 cN / dtex) were twisted to obtain a raw cord having a twist number of 47 × 47 (t / 10 cm). It was.
This cord is immersed in the first treatment liquid, and the cord with the treatment liquid is squeezed with a squeeze roll whose pressure is adjusted, and excess liquid is removed. Next, while giving a stretch rate of 4.0% to the cord to which the treatment liquid was applied, the cord was dried in an oven at 120 ° C. for 56 seconds and then heat treated in an oven at 235 ° C. for 45 seconds. The hot stretch tension at this time was 11.0 N / cord (0.50 cN / dtex).
Subsequently, the cord is immersed in the second treatment liquid, and excess liquid is removed with air. Next, while giving a relaxation rate of -2.0% to the cord to which the treatment liquid was applied, the cord was dried in a 120 ° C. oven for 56 seconds and then heat-treated in a 235 ° C. oven for 45 seconds. The normalizing tension at this time was 5.7 N / cord (0.26 cN / dtex). Table 1 shows the composition of the first treatment liquid used in Example 1, and Table 2 shows the composition of the second treatment liquid.

(Example 2)
In the treatment of Example 1, the relaxation rate at the time of drying and heat treatment after application of the second treatment liquid was changed to -1.0%. The normalizing tension at this time was 8.1 N / cord (0.37 cN / dtex). Other than that, the dip treatment was performed using the same raw cord and treatment liquid as in Example 1.

(Example 3)
In the treatment of Example 1, the relaxation rate during drying and heat treatment after the application of the second treatment liquid was changed to 0%. The normalizing tension at this time was 10.3 N / cord (0.47 cN / dtex). Other than that, the dip treatment was performed using the same raw cord and treatment liquid as in Example 1.

Example 4
In the treatment of Example 1, a raw cord having a twist number of 33 × 33 (t / 10 cm) was used, and the relaxation rate during drying / heat treatment after application of the second treatment liquid was changed to 0%. The normalizing tension at this time was 13.6 N / cord (0.62 cN / dtex). Other than that, the dip process was performed using the process liquid similar to Example 1. FIG.

(Comparative Example 1)
In the treatment of Example 1, the relaxation rate at the time of drying and heat treatment after the application of the second treatment liquid was changed to -4.0%. The normalizing tension at this time was 3.3 N / cord (0.15 cN / dtex). Other than that, the dip treatment was performed using the same raw cord and treatment liquid as in Example 1.

(Comparative Example 2)
In the treatment of Example 4, the relaxation rate during drying and heat treatment after the application of the second treatment liquid was changed to -6.0%. The normalizing tension at this time was 3.1 N / cord (0.14 cN / dtex). Otherwise, the dipping process was performed using the same raw cord and processing liquid as in Example 4.

Table 3 shows the number of twists, dip conditions, and processing cord properties of Examples 1 to 4 and Comparative Examples 1 and 2.
From the comparison of Examples 1, 2, and 3, by increasing the normalizing tension, the intermediate elongation is lowered, that is, the elastic modulus is increased.
In Example 4, by reducing the number of twists, the normalizing tension under the same relaxing condition is increased, and the intermediate elongation is further decreased.
In Comparative Examples 1 and 2, since the normalizing tension is low, the intermediate elongation is increased, the elastic modulus is insufficient, and the tire cap ply is not suitable.

  The polyester tire cap ply cord of the present invention has a high elastic modulus, has a sufficient adhesive force with rubber, and is flexible and excellent in fatigue resistance. Therefore, it is used for a tire cord, particularly a belt outer layer portion of a radial tire. It can be used for tire cap ply cords that can be used and contributes greatly to the industry.

It is a figure of the test piece used for a peeling adhesion test.

Claims (11)

  When imparting adhesiveness to rubber to the polyester fiber material, the treatment liquid contains (A) a polyepoxide compound, (B) a blocked polyisocyanate compound, and (C) a rubber latex, and the solid content weight ratio of each component is In the first treatment bath in which (A) / [(A) + (B)] is 0.05 to 0.9 and (C) / [(A) + (B)] is 0.5 to 15. The polyester tire cap ply cord is characterized in that the polyester tire cap ply cord is treated with a second treatment bath containing resorcin-formalin-rubber latex and then subjected to heat treatment under a normalizing tension adjusted to 0.2 cN / dtex or more. Production method.   The method for producing a polyester tire cap ply cord according to claim 1, wherein the normalizing tension is 0.3 cN / dtex or more.   The method for producing a polyester tire cap ply cord according to claim 1, wherein the normalizing tension is 0.4 cN / dtex or more.   The solid content weight ratio of each component of the first treatment bath is 0.1 to 0.5 for (A) / [(A) + (B)], and (C) / [(A) + (B)]. It is 1-10, The manufacturing method of the polyester tire cap ply cord in any one of Claims 1-3 characterized by the above-mentioned.   (A) The polyepoxide compound contained in the first treatment liquid is a polyglycidyl ether compound of a polyhydric alcohol, (B) the blocked polyisocyanate compound is a blocked aromatic polyisocyanate compound, and (C) the rubber latex is vinyl. The method for producing a polyester tire cap ply cord according to any one of claims 1 to 4, wherein the latex is a pyridine-styrene-butadiene-terpolymer latex.   The polyester fiber material is a cord obtained by twisting a polyethylene terephthalate fiber treated with an epoxy compound having two or more epoxy groups in a spinning or drawing or post-treatment step, and a woven fabric obtained by weaving the cord. A method for producing a polyester tire cap ply cord according to claim 1.   The strength of the treated cord is 4.5 cN / dtex or more, the elongation at the time of 2.0 cN / dtex is 5.0% or less, and the rubber coverage after the initial vulcanization in the peel adhesion test at room temperature is 90%. The polyester tire cap ply cord having a rubber coverage of 80% or more after overvulcanization.   Rubber after initial vulcanization in a heat peel adhesion test in a 150 ° C. atmosphere with a treated cord strength of 4.5 cN / dtex or higher and an elongation at a load of 2.0 cN / dtex of 5.0% or lower A polyester tire cap ply cord having a coverage of 90% or more and a rubber coverage after overvulcanization of 80% or more.   The polyester tire cap ply cord according to claim 7 or 8, wherein the treated cord has an elongation at a load of 2.0 cN / dtex of 4.0% or less.   The polyester tire cap ply cord according to claim 7 or 8, wherein the elongation of the treated cord at a load of 2.0 cN / dtex is 3.5% or less. The polyester tire cap ply cord according to any one of claims 7 to 10, wherein a twist coefficient K of the treated cord represented by K = T√D is 2500 or less.
Here, T is the number of twists of the cord (times / 10 cm), and D is the standard fineness (dtex) of the cord.

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