JP2011026743A - Polyester fiber cord for rubber reinforcement and tire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester fiber cord for rubber reinforcement, especially one preferable for a cap ply cord of radial tires, which has a high elasticity that cannot be achieved by conventional techniques, is improved in its heat adhesion resistance and heat strength retentivity resistance between the polyester fiber and rubber when it is exposed to high temperature, and has a practically sufficient fatigue resistance. <P>SOLUTION: In this polyester fiber cord for rubber reinforcement, a polyester fiber is coated with a first treatment agent containing a compound having an oxazoline group and a rubber latex and the outer layer of it is further coated with a second treatment agent containing a resorcinol-formalin-rubber latex (RFL). The first treatment agent contains 30-70 wt.% of a rubber latex against 100 wt.% of the solid content. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rubber fiber-reinforced polyester fiber cord used for tires, hoses and belts. More specifically, it has a high modulus of elasticity and has significantly improved heat-resistant adhesiveness and heat-resistant strength retention when exposed to high temperatures in rubber for a long time during rubber vulcanization processes and product use, and fatigue resistance. A polyester fiber cord for reinforcing rubber having a level of practically no problem, in particular, a polyester fiber cord for reinforcing rubber suitable as a cap ply cord for radial tires, and a tire using this polyester fiber cord for reinforcing rubber About.

  Since polyester fiber has excellent strength, elastic modulus and thermal dimensional stability, it has been widely used as a reinforcing material for rubber products such as tires, hoses and belts. When the polyester fiber is used as a reinforcing material by being embedded in a rubber product, it tends to be thermally deteriorated in a high temperature environment. The chemical thermal deterioration is influenced by the rubber itself and various additives compounded in the rubber. The rubber contains a vulcanization accelerator such as thiuram, sulfenamide, or guanidine, and an amine anti-aging agent. Polyester fibers that have been subjected to high-temperature treatment in the rubber are mainly used for these. Amine decomposition and hydrolysis are caused by amine compounds, low molecular weight compounds generated by oxidative degradation of the rubber itself, water molecules, moisture contained in the rubber, and the like. Such an amine-decomposed or hydrolyzed polyester fiber has a problem that initial properties such as adhesion and strength are remarkably deteriorated, so that it cannot be used.

  When the polyester fiber is amine-decomposed or hydrolyzed, the strength is reduced due to the molecular chain breakage and the adhesiveness between the rubber and the fiber layer is lowered. However, when polyester fiber is used as a rubber reinforcing fiber, a tire having high strength, high elastic modulus, and excellent thermal dimensional stability can be obtained, and fatigue resistance and adhesion can be improved. In recent years, it has been used as a carcass material for most passenger car radial tires, coupled with improvements in tire manufacturing technology.

  However, since polyester fibers have the above-mentioned essential drawbacks, the heat generated during high-speed running of tires is hard to be trapped and difficult to chemically deteriorate. Therefore, polyester fibers are limited to carcass materials for passenger cars having a relatively small tire size. Currently, it is used only for a part of large tires such as trucks and buses. In general, polyester fiber cords are not currently used in the fields of trucks, bus tires, aircraft tires, large passenger car tires and racing car tires.

  Moreover, in recent years, high-performance tires suitable for high-speed driving have been increasingly demanded, and radial tires developed to meet these demands are designed to securely expand the tire due to centrifugal force during high-speed driving and compression when touched from the top of the steel belt. Cap ply cords have been used to suppress this. Since this cap ply cord generates heat and becomes higher in temperature than the carcass portion, nylon 66 fibers that are not suitable for use with conventional polyester cords and have excellent adhesion at high temperatures are used.

  However, as a characteristic of the cap ply cord, a high elastic modulus is preferable. Therefore, a polyester fiber is preferable as a fiber material, and the polyester fiber is advantageous in terms of cost as compared with nylon 66 fiber, and is used for a cap ply. There was a strong demand for the development of possible polyester fiber cords. In order to achieve this, first, a great improvement in heat-resistant adhesion is required, and secondly, an improvement in heat-resistant and strong retention is required.

  The following four examples are given as typical conventional techniques for improving the heat-resistant adhesion of polyester fibers.

  (1) A cord treated with an RFL containing an epoxy compound after treating a polyester fiber with a treatment solution containing (A) a carrier and (B) a treatment solution containing a blocked isocyanate aqueous solution (see, for example, Patent Document 1).

  (2) A cord obtained by treating polyester fiber with a treatment liquid containing a thermoplastic polymer, a heat-reactive water-based urethane, and an epoxy compound, and a cord having an elastic modulus in a 160 ° C. atmosphere equal to or higher than a predetermined elastic modulus (for example, , See Patent Document 2).

  (3) A cord obtained by treating a polyester fiber with a treatment liquid containing an ethylenically unsaturated acid-modified styrene-butadiene-rubber latex, a heat-reactive aqueous urethane, and an epoxy compound (for example, see Patent Document 3).

  (4) A cord obtained by treating a polyester fiber with a treatment liquid containing a thermoplastic elastomer, a blocked isocyanate, and an oxazoline compound (for example, see Patent Document 4).

  However, according to the prior arts (1) to (4) above, although improvement in heat-resistant adhesion and heat-resistant strength retention at high temperatures is recognized to some extent as compared with conventional polyester fiber bonding methods, It was not sufficient or the fatigue resistance was not sufficient. In particular, it was not at a level that could be put into practical use as a cap ply cord for a radial tire that is an object of the present invention.

JP 2006-2327 A (Claims) Japanese Patent Laying-Open No. 2005-112065 (Claims) JP 2008-169504 A (Claims) JP 2006-2104013 A (Claims)

  Therefore, the object of the present invention, which has not been achieved by the above-described prior art, has a high elastic modulus, and improved heat-resistant adhesion and heat-resistant strength retention between polyester fiber and rubber when exposed to high temperatures, Another object of the present invention is to provide a polyester fiber cord for reinforcing rubber having practically sufficient fatigue resistance, and particularly suitable for a cap ply cord of a radial tire.

  In order to achieve the above object, according to the present invention, a polyester fiber is coated with a first treatment agent containing a compound having an oxazoline group and a rubber latex, and its outer layer is made of resorcin / formalin / rubber latex (RFL). A polyester fiber cord for reinforcing rubber coated with a second treating agent, wherein the first treating agent contains 30 to 70% by weight of rubber latex in 100% by weight of the total solid content, and The durometer hardness of the dry film by the first treatment agent is A40 to A80, and the durometer hardness after heat-treating the dry film by the first treatment agent at 170 ° C. for 70 minutes is A50 to A90. A polyester fiber cord for reinforcing rubber is provided.

In the polyester fiber cord for rubber reinforcement of the present invention,
The breaking elongation of the dry film by the first treating agent is 300% to 1000%, and the breaking elongation after heat-treating the dry film by the first treating agent at 170 ° C. for 70 minutes is 150% to 700%. There is,
The tensile strength of the dry film with the first treatment agent is 1 MPa to 6 MPa, and the tensile strength after heat-treating the dry film with the first treatment agent at 170 ° C. for 70 minutes is 2 MPa to 7 MPa,
In 100 parts by weight of the total solid content of the rubber latex contained in the first treatment agent, a styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex having a glass transition temperature (Tg) of 0 ° C. to 35 ° C. 10 to 80 parts by weight included,
The elongation at break of the dry film by the styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex is 5% to 400%,
A styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex having a glass transition temperature (Tg) of 0 ° C. to 35 ° C. is included in resorcin / formalin rubber latex (RFL) as the second treatment agent. And the resin adhesion amount of the film by the first treatment agent is 1 to 4% by weight, the resin adhesion amount of the film by the second treatment agent is 1 to 4% by weight, and the coating film by these first treatment agents And the total resin adhesion amount of the film by the second treatment agent is 2 to 6% by weight,
Are mentioned as preferable conditions.

  Moreover, the tire of the present invention is characterized by using the above-mentioned rubber reinforcing polyester fiber cord as a cap ply member.

  According to the present invention, it has a high elastic modulus, and during the rubber vulcanization process or product use, the heat-resistant adhesiveness and heat-resistant strength retention when exposed to a high temperature for a long time in rubber are remarkably improved, and A polyester fiber cord for rubber reinforcement that has practically sufficient fatigue resistance is obtained. A rubber product reinforced with a polyester fiber cord according to the present invention can withstand severe use for a long period of time when used as a tire, belt and hose. In particular, it is suitable as a cap ply cord for a radial tire that could not be applied with a conventional polyester fiber cord.

  The present invention is described in detail below.

  The polyester fiber used in the present invention is composed of a polyester composed of a dicarboxylic acid and a glycol component, and polyethylene terephthalate composed of terephthalic acid and ethylene glycol is particularly preferred.

The polyester fiber cord for rubber reinforcement of the present invention has excellent mechanical properties such as high strength, high toughness, high elastic modulus, low shrinkage, and high fatigue resistance, and is exposed to a high temperature in rubber for a long time. In addition, the polyester fiber used in the present invention preferably has the following characteristics because it has excellent chemical durability such as hydrolysis resistance and amine decomposition resistance.
(1) Intrinsic viscosity (IV) = 0.7 to 1.2, more preferably 0.8 to 1.1
(2) Carboxyl end group (COOH) = 10-30 eq / t, more preferably 12-25 eq / t
(3) Content of diethylene glycol (DEG) = 0.5 to 1.5% by weight, preferably 0.5 to 1.2% by weight
(4) Strength (T) = 6.0 to 10.0 cN / dtex, more preferably 7.0 to 9.0 cN / dtex
(5) Elongation (E) = 8-20%, more preferably 10-16%
(6) Intermediate elongation (ME) = 4.0-6.5%, more preferably 4.5-6.0%
(7) Dry heat shrinkage (ΔS150 ° C.) = 2.0 to 12.0%, more preferably 3.0 to 10.0%

  In order for the polyester fiber used for the polyester fiber cord for rubber reinforcement of the present invention to have chemical durability, it is advantageous that the viscosity is high, the carboxyl end groups are small, and the diethylene glycol is small.

  The polyester fiber used in the present invention may be modified with a terminal carboxyl group blocking agent such as a carbodiimide compound, an epoxy compound, an isocyanate compound and an oxazoline compound in order to reduce the carboxy terminal group.

  Further, the polyester fiber of the present invention may be provided with a polyepoxide compound in advance in the yarn making process. Examples of the polyepoxide compound that can be used in the present invention include compounds containing 0.1 g equivalent or more per 100 g of the compound in at least two epoxy groups in one molecule. Specifically, reaction products of polyhydric alcohols such as pentaerythritol, ethylene glycol, polyethylene glycol, propylene glycol, glycerol, sorbitol and halogen-containing epoxides such as epichlorohydrin, unsaturated by peroxide or hydrogen peroxide, etc. Polyepoxide compound obtained by oxidizing compound, ie, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylene carboxylate, bis (3,4-epoxy-6-methyl-cyclohexylmethyl) adipate, phenol novolak type , Hydroquinone type, biphenyl type, bisphenol S type, brominated novolak type, xylene modified novolak type, phenol glyoxal type, trisoxyphenylmethane type, trisphenol PA type, bis Aromatic polyepoxides such as phenol-type polyepoxides can be mentioned. Particularly preferred are polyepoxides of sorbitol glycidyl ether type or cresol novolac type.

  These compounds are usually used as an emulsified liquid, but in order to make an emulsified liquid or solution, a known emulsifier such as a compound obtained by dissolving the compound as it is or in a small amount of a solvent as necessary, for example, It is used by emulsifying or dissolving using sodium alkylbenzene sulfonate, dioctyl sulfosuccinate sodium salt, nonylphenol ethylene oxide adduct and the like.

  The polyepoxide compound is applied together with a spinning oil agent in a process for producing a polyester fiber. The amount of the polyepoxide compound attached at this time is in the range of 0.1 to 5% by weight. When the adhesion amount of the polyepoxide compound is less than 0.1% by weight, the effect of the polyepoxide compound is not sufficiently exerted, and there is a possibility that satisfactory adhesion between the polyester fiber and the rubber cannot be obtained. On the other hand, when the adhesion amount of the polyepoxide compound exceeds 5% by weight, the fiber becomes very hard and not only difficult to impart in the yarn making process, but also the permeability of the treatment agent to be treated in the subsequent process is lowered. As a result, the adhesive performance is lowered, which is not preferable.

  The polyester fiber used in the present invention is not limited by the fineness, the number of filaments, the cross-sectional shape, etc., but usually 200-5000 dtex, 30-1000 filament, circular cross-section yarn is used, 250-3000 dtex, 50-500 filament, A circular section yarn is preferred.

  The polyester fiber cord for reinforcing rubber of the present invention is obtained by twisting the above polyester fiber into a raw cord, woven the raw cord as it is, or after weaving the raw cord, and then treating with an adhesive. The raw cords used for ordinary carcass tire cords are twisted in the S or Z direction, then two or three twisted cords are combined and the same number of twists are applied in the opposite direction to the twisted cord. It is what. Next, the raw cord is used as a warp, and the weft is covered with cotton yarn or the polyester fiber is covered with cotton yarn to obtain a weft, which is woven in a raw fabric. Next, the ginger fabric is treated with an adhesive to obtain a dip fabric.

  On the other hand, in the case of hoses, belts, and cap ply cords, apply the lower twist, keep the lower twist cord, or, as before, combine two or three of the same number of upper twists in the direction opposite to the lower twist. Spiral cords are formed, and the dip cords are formed by the adhesive treatment in the form of the cords.

  The polyester fiber cord for reinforcing rubber to which the adhesive of the present invention is applied refers to both the dip anti-dip and the dip cord.

The polyester fiber cord of the present invention is preferably a twisted yarn cord subjected to a lower twist and an upper twist. At this time, the lower twist coefficient K1 is preferably 600 ≦ K1 ≦ 2000, more preferably 800 ≦ K1 ≦ 2000, and still more preferably 1000 ≦ K1 ≦ 2000. If the lower twisting coefficient is out of the preferred range, the adhesive strength after high temperature exposure may be reduced, or the fatigue resistance in rubber may be deteriorated. The upper twist coefficient K2 is preferably 800 ≦ K2 ≦ 3000, more preferably 1200 ≦ K2 ≦ 3000, and further preferably 1600 ≦ K2 ≦ 3000. When the upper twist coefficient is out of the preferred range, the adhesive strength after high temperature exposure may be reduced, or the fatigue resistance in rubber may be deteriorated. (Where K = T × D ^1/2 , K: twist coefficient, T: number of twists per unit length (times / 10 cm), D: fineness)

  In the polyester fiber cord for reinforcing rubber of the present invention, the polyester fiber is coated with a first treatment agent containing a compound having an oxazoline group and a rubber latex, and further contains resorcin / formalin / rubber latex (RFL) in the outer layer. It is coated with a treatment agent.

  The compound having an oxazoline group used in the present invention refers to a compound having an oxazoline group (preferably a 2-oxazoline group) at the terminal or side chain of a substance having a main skeleton of a general organic compound, organic polymer, or oligomer. One or two or more oxazoline groups can be present in the skeleton, but it is more preferable to have many oxazoline groups that are reactive functional groups in order to improve adhesion performance. As the skeleton of the main chain of the oxazoline group-containing substance, hydrocarbon polymers, ethylene glycol chains, bisphenols such as bisphenol A, and initial polymers such as phenol resins, novolac resins, and resole resins are used. Also used are substances containing aromatic rings and heterocyclic rings. Furthermore, substances containing an oxazoline group at the terminal or side chain of the main component monomer and / or polymer or oligomer comprising the same are also useful. As these monomers, styrene, styrene derivatives, acrylonitrile, methacrylic acid esters, methacrylic acid, ethylene, butadiene, acrylamide, etc. are used, and these are used as a single polymer and / or oligomer and also as a copolymer. . It can also be used as a mixture thereof.

  The form of the oxazoline group-containing substance is liquid, molten, solid, or a solution in water or an organic solvent that can dissolve these, and a suspension dispersed in water (emulsion particles, latex particles, etc.). used. For example, a method of emulsifying or dissolving a compound obtained by dissolving such a compound as it is or in a small amount of a solvent using a known emulsifier such as sodium alkylbenzene sulfonate, dioctyl sulfosuccinate sodium salt, nonylphenol ethylene oxide adduct, etc. May be used.

  Furthermore, the compound having an oxazoline group preferably has a glass transition temperature (Tg) of −20 ° C. to 70 ° C. Outside this range, the heat resistant adhesive strength may be insufficient.

  The ratio of the compound having an oxazoline group to the total solid content of the first treatment agent is preferably 5% by weight or more, more preferably 10% by weight or more as a lower limit in terms of dry weight. Moreover, as an upper limit, it is preferable that it is 50 weight% or less, More preferably, it is 40 weight% or less. If it is less than 5% by weight, the adhesive strength may be insufficient, and if it exceeds 50% by weight, the cord becomes hard and fatigue resistance may be deteriorated.

  The rubber latex that can be used for the first treating agent in the present invention needs to be contained in an amount of 30 to 70% by weight, more preferably 30 to 60% by weight, in 100% by weight of the total solid content of the first treating agent. If it exceeds this range, the adhesive strength may be insufficient, and if it is less than this range, the fatigue resistance may deteriorate.

  Examples of the rubber latex that can be used in the present invention include natural rubber latex, butadiene rubber latex, styrene / butadiene rubber latex, vinylpyridine / styrene / butadiene rubber latex, nitrile rubber latex, hydrogenated nitrile rubber latex, chloroprene rubber latex, chloro Examples thereof include sulfonated rubber latex and ethylene / propylene / diene rubber latex, and these can be used alone or in combination. Among these, it is most preferable that a styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex is included from the viewpoint of improving heat-resistant adhesion.

  Examples of the ethylenically unsaturated acid used herein include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, itaconic acid, fumaric acid, maleic acid, and butenetricarboxylic acid, itaconic acid monoethyl ester, Monoalkyl esters of unsaturated dicarboxylic acids such as fumaric acid monobutyl ester and maleic acid monobutyl ester, and unsaturated sulfonic acids such as sulfoethyl sodium acrylate, sulfopropyl sodium methacrylic acid, acrylamide propane sulfonic acid or alkalis thereof A salt etc. are mentioned, These can be used 1 type or in combination of 2 or more types.

  The carboxyl group may be introduced into the latex by copolymerizing an ethylenically unsaturated acid ester monomer or an ethylenically unsaturated acid anhydride monomer and then hydrolyzing it. Examples of ethylenically unsaturated acid ester monomers and ethylenically unsaturated acid anhydride monomers include acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, itaconic acid, fumaric acid, maleic acid, and butenetricarboxylic acid. Examples thereof include mono-, di-, or triesters of unsaturated carboxylic acids and maleic anhydride, and these can be used alone or in combination.

  Further, from the viewpoint of achieving both adhesion to rubber and bending fatigue resistance, the styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex has a glass transition temperature (Tg) of 0 to 35 ° C. It is preferable that the temperature is 5 to 30 ° C.

  Furthermore, from the viewpoint of improving the flexibility of the cord and the bending fatigue resistance, the breaking elongation of the dry film by the styrene-butadiene-ethylenic unsaturated acid monomer copolymer latex is 5% to 400%. Is more preferable, and 10% to 300% is more preferable.

  The rubber latex that can be used for the first treating agent in the present invention can be mixed with a rubber latex in addition to the styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex, but it further improves the heat resistant adhesiveness. From the viewpoint, the total amount of solids of the styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex and other rubber latex is 100 parts by weight, and the styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex is It is preferable to add so that it may contain 10-80 weight part (dry weight part). Although it does not specifically limit as another rubber latex, A vinylpyridine * styrene * butadiene rubber latex can be used conveniently.

  It is preferable to mix an epoxy compound with the 1st processing agent of this invention from a viewpoint of improving heat resistant adhesiveness. The epoxy compound that can be used in the present invention has two or more epoxy groups in one molecule.

  The compound having two or more epoxy groups in the molecule includes, for example, a glycidyl ether type epoxy resin obtained from a compound having a hydroxyl group in the molecule, a glycidyl amine type epoxy resin obtained from a compound having an amino group in the molecule, A glycidyl ester type epoxy resin obtained from a compound having a carboxyl group, a cyclic aliphatic epoxy resin obtained from a compound having an unsaturated bond in the molecule, a heterocyclic epoxy resin such as triglycidyl isocyanate, or the like. An epoxy resin in which two or more types are mixed in the molecule.

  Specific examples of glycidyl ether type epoxy resins include bisphenol A type epoxy resins obtained by reaction of bisphenol A and halogen-containing epoxides such as epichlorohydrin, and bisphenol F obtained by reaction of halogen-containing epoxides. Bisphenol F-type epoxy resin, biphenyl-type epoxy resin obtained by reaction of biphenyl with the halogen-containing epoxide, resorcinol-type epoxy resin obtained by reaction of resorcinol with the halogen-containing epoxide, bisphenol S and the halogen-containing epoxide Bisphenol S-type epoxy resin obtained by reaction with polyhydric acid, polyethylene glycol type epoxy resin which is a reaction product of polyhydric alcohols and the above halogen-containing epoxides, Epoxy resins obtained by oxidizing unsaturated bonds such as pyrene glycol type epoxy resin, bis- (3,4-epoxy-6-methyl-dicyclohexylmethyl) adipate, 3,4-epoxycyclohexene epoxide, and other naphthalene type epoxies Resins, phenol novolac type epoxy resins, cresol novolac type epoxy resins, and their halogen or alkyl-substituted products can be used.

  The durometer hardness of the dry film obtained by the method described in the examples described later of the first treatment agent used in the present invention needs to be in the range of A40 to A80, preferably in the range of A40 to A70. Furthermore, the durometer hardness after heat-treating the dry film obtained by the method described in the examples described later of the first treatment agent at 170 ° C. for 70 minutes needs to be in the range of A50 to A90, preferably It is in the range of A60 to A80. If the durometer hardness is lower than this range, the heat-resistant adhesive strength may be deteriorated. If the durometer hardness is higher than this range, the heat-resistant adhesive strength and fatigue resistance may be deteriorated. The durometer hardness of the coating film by the treatment agent can be measured by the method described later, and this durometer hardness can be adjusted by the type of drug mixed with the treatment agent and the mixing ratio.

  The breaking elongation of the dry film obtained by the method described in the examples described later of the first treating agent used in the present invention is preferably in the range of 300% to 1000%, more preferably 400% to 900%. Range. Furthermore, the elongation at break after heat-treating the dry film obtained by the method described in the examples described later at 170 ° C. for 70 minutes is preferably in the range of 150 to 700%, more preferably in the range of 200 to 600%. It is. When the elongation at break is a value below this range, the heat-resistant adhesive force and fatigue resistance may be deteriorated, and when the value is above this range, the heat-resistant adhesive force may be deteriorated. The breaking elongation of the film by the treatment agent can be measured by the method described later, and the breaking elongation can be adjusted by the type of drug mixed with the treatment agent and the mixing ratio.

  Moreover, it is preferable that the tensile strength of the dry film obtained by the method of the Example description mentioned later of the 1st processing agent used by this invention exists in the range of 1 MPa-6 MPa, More preferably, it is the range of 1 MPa-4 MPa. . Furthermore, it is preferable that the tensile strength after heat-treating the dry film obtained by the method described in the Examples described later of the first treatment agent at 170 ° C. for 70 minutes is in the range of 2 MPa to 7 MPa, more preferably 2.5 MPa. It is in the range of ~ 6 MPa. When the tensile strength is outside this range, the heat-resistant adhesive force and fatigue resistance may be deteriorated. The tensile strength of the coating film by the treatment agent can be measured by the method described later, and the tensile strength can be adjusted by the type of drug mixed with the treatment agent and the mixing ratio.

  The solid content of the coating with the first adhesive treatment agent on the polyester fiber is preferably in the range of 1 to 4% by weight, more preferably in the range of 1.5 to 3.5% by weight with respect to the fiber weight. There should be. When the solid content is too low, the adhesiveness is lowered. On the other hand, when the solid content is too high, the cord becomes hard and fatigue resistance is lowered, which is not preferable.

  The main components of the second treating agent of the rubber fiber-reinforced polyester fiber cord of the present invention are a resorcin / formaldehyde initial condensate and a rubber latex. The resorcin / formaldehyde is particularly preferably prepared using a resorcin / formaldehyde initial condensate obtained by initial condensation in the presence of an alkali catalyst. For example, resorcin and formaldehyde are added and mixed in an alkaline aqueous solution containing an alkaline compound such as sodium hydroxide, and allowed to stand at room temperature for several hours. After the initial condensation of resorcin and formaldehyde, a rubber latex is added to the mixed emulsion. It is prepared by the method.

  As the resorcin / formaldehyde initial condensate, a resorcin / formaldehyde molar ratio of 1: 0.3 to 1: 5, preferably 1: 0.75 to 1: 2.0 is used. If the molar ratio of formaldehyde is less than the above range, the treatment cord may become sticky and may cause the processing machine to become dirty.On the other hand, if the molar ratio of formaldehyde is above this range, the adhesion will be insufficient. May be.

  Examples of the rubber latex used for the preparation of resorcinol, formaldehyde latex are natural rubber latex, butadiene rubber latex, styrene-butadiene-rubber latex, styrene-butadiene-vinylpyridine-rubber latex, nitrile rubber latex, hydrogenated nitrile rubber latex. Chloroprene rubber latex, chlorosulfonated rubber latex, ethylene / propylene / diene rubber latex and the like, and these can be used alone or in combination. Among them, it is preferable to use vinylpyridine / styrene / butadiene rubber latex alone or in combination with another. More preferably, a styrene-butadiene-vinylpyridine-ethylenically unsaturated acid monomer copolymer latex obtained by copolymerizing an ethylenically unsaturated acid with a styrene-butadiene-vinylpyridine-rubber latex alone or others. It is preferable to use in combination.

  Examples of the ethylenically unsaturated acid used herein include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, itaconic acid, fumaric acid, maleic acid, and butenetricarboxylic acid, itaconic acid monoethyl ester, Monoalkyl esters of unsaturated dicarboxylic acids such as fumaric acid monobutyl ester and maleic acid monobutyl ester, and unsaturated sulfonic acids such as sulfoethyl sodium acrylate, sulfopropyl sodium methacrylic acid, acrylamide propane sulfonic acid or alkalis thereof A salt etc. are mentioned, These can be used 1 type or in combination of 2 or more types.

  The carboxyl group may be introduced into the latex by copolymerizing an ethylenically unsaturated acid ester monomer or an ethylenically unsaturated acid anhydride monomer and then hydrolyzing it. Examples of ethylenically unsaturated acid ester monomers and ethylenically unsaturated acid anhydride monomers include acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, itaconic acid, fumaric acid, maleic acid, and butenetricarboxylic acid. Examples thereof include mono-, di-, or triesters of unsaturated carboxylic acids and maleic anhydride, and these can be used alone or in combination.

  Furthermore, in the second treating agent of the present invention, a styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex having a glass transition temperature (Tg) of 0 ° C. to 35 ° C., more preferably 5 to 30 ° C. It is preferable from a viewpoint of heat resistant adhesive improvement that the styrene-butadiene-ethylenic unsaturated acid monomer copolymer latex which is is contained.

  The blending ratio of the resorcin / formaldehyde initial condensate and the rubber latex in the resorcin / formaldehyde / rubber latex (RFL) is preferably 1: 3 to 1: 8 in terms of solids weight ratio, and is preferably 1: 4 to 1: 6. More preferably, it is in the range. Outside this range, the adhesion may be insufficient. Further, the blending ratio of resorcin / formaldehyde / rubber latex and the phenolic compound is preferably 10: 1 to 10: 5, more preferably 10: 2 to 10: 4 in terms of solid content weight ratio. That is good. Outside this range, the adhesion may be insufficient.

  Further, the second treating agent of the present invention can contain (P) chloro-modified resorcin from the viewpoint of further improving the adhesiveness. (P) Chloro-modified resorcin is a compound obtained by condensing parachlorophenol, formalin and resorcin, and is a phenol compound represented by the following general formula (I).

However, W in the formula is CH ₂ , S, S—S, at least part of X and Y represents Cl, and the rest is selected from Br, I, H, OH and a C ₁ -C ₆ alkyl group. M is an integer of 1-15. The chloro-modified resorcin represented by the above formula is an initial condensate of a halogenated phenol compound and formaldehyde, an initial condensation particle of sulfur-modified resorcin and formaldehyde, or an initial condensate of sulfur-modified resorcin and formaldehyde.

  The method for preparing these (P) chloro-modified resorcins is not particularly limited, and examples thereof include parachlorophenol, orthochlorophenol, parabromophenol, paraiodophenol, orthocresol, paracresol, paratertiary butylphenol and 2,5-dimethyl. Phenol and the like are mentioned as starting materials, and parachlorophenol, parabromophenol, paracresol, and paratertiary butylphenol are particularly preferable, and parachlorophenol is particularly preferably used.

  By condensing such a starting material with formaldehyde in the presence of an alkali catalyst, or by reacting a condensate obtained by previously reacting the starting material in the presence of an acid catalyst with formaldehyde in the presence of an alkali catalyst. A phenolic compound can be obtained.

  Specific examples of (P) chloro-modified resorcinol include 2,6-bis (2 ′, 4′-dihydroxy-phenylmethyl) -4-chlorophenol (“Kasabond” manufactured by Thomas One Co., Ltd., Nagase Kasei Kogyo Co., Ltd.) Among them, those mainly composed of a chlorophenol compound having 3 or more benzene nuclei are preferably used from the viewpoints of adhesiveness and process passability.

  The blending ratio of (P) chloro-modified resorcin represented by the above general formula (I) to resorcin / formalin / rubber latex (RFL) is P / RFL = 1/1 to 1/5 in terms of solid content weight ratio. It is preferable that P / RFL = 1/2 to 1/4. When P / RFL> 1/1, the cord may be hard, and when P / RFL <1/5, the adhesiveness may decrease.

  Moreover, the 2nd processing agent of this invention can contain a blocked polyisocyanate compound and / or an ethyleneimine compound from a viewpoint of improving adhesiveness further.

  Examples of the blocked polyisocyanate compound and / or ethyleneimine compound that can be used in the present invention include polyisocyanate compounds such as tolylene diisocyanate, metaphenylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, and triphenylmethane triisocyanate, and phenol and cresol. And reaction products with phenols such as resorcin, lactams such as ε-caprolactam and valerolactam, oximes such as acetoxime, methyl ethyl ketone oxime and cyclohexane oxime, and blocking agents such as ethyleneimine. Among these compounds, aromatic polyisocyanate compounds blocked with ε-caprolactam and aromatic ethylene urea compounds such as diphenylmethane diethylene urea can be preferably used.

  In the polyester fiber cord of the present invention, the amount of the resin component attached to the film by the second adhesive treatment agent is preferably in the range of 1 to 4% by weight, more preferably 1.5 to 3.5% with respect to the fiber weight. It is in the range of wt%. If the resin adhesion amount is too low, the adhesiveness will be reduced, while if the resin adhesion amount is too high, the cord will be hard and fatigue resistance will be reduced, or the solid content will gum up on the roll in the process, Operational stability may deteriorate.

  In the polyester cord of the present invention, the total resin adhesion amount of the coating with the first treatment agent and the coating with the second treatment agent is preferably in the range of 2 to 6% by weight, more preferably with respect to the fiber weight. Is in the range of 2.5 to 5.5% by weight. If the resin adhesion amount is too low, the adhesiveness will be reduced, while if the resin adhesion amount is too high, the cord will be hard and fatigue resistance will be reduced, or the solid content will gum up on the roll in the process, Operational stability may deteriorate.

  The polyester fiber cord of the present invention characterized by the above is remarkably improved in heat-resistant adhesion and heat-resistant strength retention when exposed to a high temperature for a long time during a rubber vulcanization process or in use of a rubber product. A rubber product reinforced with a polyester fiber cord according to the present invention can withstand severe use for a long period of time when used as a tire, belt and hose. In particular, it is suitable as a cap ply cord for a radial tire that could not be applied with a conventional polyester fiber cord.

  Next, the manufacturing method of the polyester fiber cord for rubber reinforcement of this invention is demonstrated.

  In the method for producing a rubber reinforcing polyester fiber cord to which an adhesive has been applied by the two-bath dip method, the rubber reinforcing polyester fiber cord of the present invention includes a first treatment agent containing a compound having an oxazoline group and a rubber latex. It is preferable to obtain by applying a second treatment agent containing resorcin / formalin / rubber latex in the second bath.

  The polyester fiber used in the present invention is twisted to form a raw cord having the above-described twist coefficient, and then the cord is woven using a loom for weaving. In the case of a hose, a belt, and a cap ply cord, the lower twist cord or the various yarn cords may be used for the next dipping step without weaving.

  The present invention can be produced by a two-bath dip method. In the first bath, a first treatment agent containing a compound having an oxazoline group and a rubber latex is applied, and in the second bath, resorcin / formalin / rubber latex (RFL). It is preferable to provide the 2nd processing agent containing.

  In the first bath, a method for applying a first treatment agent containing a compound having an oxazoline group and a rubber latex is obtained by adding a polyester fiber raw cord or raw cord to a dip solution prepared by adjusting an adhesive containing the component as an aqueous solution or aqueous dispersion. It is carried out by dipping the ridge, followed by drying and heat treatment. The total solid concentration of the dip liquid in the first bath is 2 to 20% by weight, preferably 3 to 15% by weight. If the solid content concentration is too low, the adhesive surface tension increases, the uniform adhesion to the polyester fiber surface decreases, and the adhesion decreases due to a decrease in the solid content, and the solid content concentration decreases. If it is too high, it is not preferable because the amount of solid content is excessive and the cord becomes hard and the fatigue resistance may be lowered.

  Moreover, it is preferable to use a dispersing agent, that is, a surfactant in the dip solution of the first bath at 10% by weight or less, preferably 5% by weight or less based on the total solid content of the dip solution. If it exceeds 10% by weight, the adhesiveness is lowered.

  The solid content of the dip liquid in the first bath with respect to the polyester fiber is preferably in the range of 1 to 4% by weight, more preferably in the range of 1.5 to 3.5% by weight with respect to the fiber weight. If the solid content is too low, the adhesiveness is lowered. On the other hand, if the solid content is too high, the cord becomes hard and fatigue resistance may be reduced. In order to control the solid content adhesion amount to the polyester fiber, for example, a method of squeezing with a pressure roller, scraping with a scrubber, etc., blowing with pressurized air, suction or the like after being immersed in a dip solution can be used. Moreover, in order to increase the amount of adhesion, it can also be made to adhere several times.

  The polyester fiber cord to which the first bath dip solution is applied is dried at 70 to 150 ° C. for 0.5 to 5 minutes (hereinafter referred to as dry treatment) and then heat treated at 200 to 255 ° C. for 0.5 to 5 minutes (hereinafter referred to as “dry treatment”). This is referred to as hot treatment) to form a coating film with an adhesive on the fiber surface, but in some cases, drying can be omitted.

  When the temperature of the heat treatment is less than 200 ° C., the formation of a film with an adhesive on the fiber and the reaction with the rubber are insufficient, and the adhesive force may be insufficient, whereas at a high temperature exceeding 255 ° C., This is not preferable because the film formed by the treatment agent formed on the fiber is deteriorated to lower the adhesive force, or the polyester fiber is thermally deteriorated to lower the strength.

  After applying the first bath dip solution as described above, a second treating agent containing resorcin, formalin, rubber latex (RFL) is subsequently adhered.

  The second bath dip solution containing resorcin / formalin / latex preferably has a solid concentration of 5 to 30% by weight, more preferably 10 to 25% by weight. If it is less than 5% by weight, the solid content of the dip liquid in the second bath may be insufficient, and the adhesive strength may not be sufficient. When the solid content concentration exceeds 30% by weight, the storage stability of the dip solution deteriorates, the solid content aggregates and the concentration changes, and it becomes difficult to uniformly attach the dip solution to the surface of the polyester fiber cord. .

  The solid content of the second bath with respect to the polyester fiber cord is preferably in the range of 1 to 4% by weight, more preferably in the range of 1.5 to 3.5% by weight. If the solid content is too low, the adhesiveness may decrease, while if the solid content is too high, the cord may become hard and fatigue resistance may decrease. Gum up of solid content occurs in the roll, and operation stability may be deteriorated.

  In order to control the solid content adhesion amount to the polyester fiber, for example, a method such as squeezing with a pressure roller, scraping with a scrubber, blowing with pressurized air, suction, or the like can be used. Moreover, you may make it adhere several times in order to increase the adhesion amount.

  The polyester fiber cord to which the second bath dip solution is applied is dried at 70 to 150 ° C. for 0.5 to 5 minutes (dry treatment) and then heat treated at 200 to 255 ° C. for 0.5 to 5 minutes (hot treatment). In order to control the physical properties of the cord, a coating with an adhesive can be formed on the fiber surface by heat treatment at 200 to 255 ° C. for 0.5 to 5 minutes (hereinafter referred to as normalizing treatment), but drying may be omitted in some cases. You can also If the temperature of the hot treatment and normalization treatment is less than 200 ° C., the formation of a film with an adhesive on the fiber and the adhesion to the rubber may be insufficient, whereas at a temperature higher than 255 ° C., it may be on the fiber. It is not preferable because the coating film formed by the treatment agent is deteriorated to lower the adhesive strength, or the polyester fiber is thermally deteriorated to be strongly reduced.

  The polyester fiber cord for rubber reinforcement of the present invention produced by the above-mentioned two-bath dip method includes a first treatment agent layer containing a compound having an oxazoline group and a rubber latex, and a second treatment agent layer containing a resorcin / formalin / rubber latex. This is a polyester fiber cord for reinforcing rubber. It is excellent in heat-resistant adhesiveness and heat-resistant strength retention, and has practically sufficient fatigue resistance. When used as a rubber material such as conventional tire carcass materials, hoses and belts, it can withstand severe use for a long time. Therefore, it can be suitably used as a cap ply member of a tire that could not be applied conventionally.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. In the present invention, the methods for measuring and evaluating the physical properties of the polyester fiber cord for rubber reinforcement are as follows.

(1) Amount of resin adhesion The weight of the twisted cord per fixed length was measured in advance, and the amount of the resin adhesion as a difference was calculated by measuring the weight of the cord of the same length after the adhesive treatment.

(2) T-initial adhesive strength and T-heat resistant adhesive strength This indicates the adhesive strength between the treatment cord and rubber. In accordance with JIS L-1017 (2002) Adhesive Strength-A method, the treated cord is embedded in unvulcanized rubber. Under pressure, the initial adhesive strength is 150 ° C. for 30 minutes, and the heat resistant adhesive strength is 170 ° C. for 70 minutes. After being allowed to cool, the cord was pulled out from the rubber block at a speed of 300 mm / min, and the load required for the drawing was displayed in N / cm.

In addition, the composition of the rubber compound used for the measurement of T-adhesion force is as follows. Natural rubber (RSS # 1): 70 (parts by weight)
SBR (JSR1501): 30 (parts by weight)
RF carbon black: 40 (parts by weight)
Stearic acid: 2 (parts by weight)
Sulfur: 2 (parts by weight)
Zinc flower: 5 (parts by weight)
2,2′-dithiobenzothiazole: 4 (parts by weight)
Naphthenic acid process oil: 3 (parts by weight).

(3) Durometer hardness The aqueous dispersion of the first treatment agent was applied to a glass plate so that the thickness of the coating after drying was 5 mm, dried at room temperature for 72 hours, peeled off from the glass plate, and then heated in a 120 ° C oven. What was heat-processed for 15 minutes was used as a dry film, and two sheets were stacked to prepare a thickness of 10 mm. Further, the dried film was further heat-treated in a 170 ° C. oven for 70 minutes to prepare two sheets having a thickness of 10 mm by overlapping two sheets. Using a type A durometer (manufactured by Shimadzu Corporation), this is done according to JIS K-6253 (2006) 6. Evaluation was made by a durometer hardness test. When it exceeded A90, it was set as A90.

(4) Tensile strength and breaking elongation after heat treatment at 170 ° C. for 70 minutes of the dried film and the dried film with the first treatment agent A glass plate so that the thickness of the coating after drying the aqueous dispersion of the first treatment agent is 2 mm After drying at room temperature for 72 hours, it was peeled off from the glass plate and heat-treated in a 120 ° C oven for 15 minutes to form a dry film, and the dried film was further heat-treated in a 170 ° C oven for 70 minutes. did. These were punched out with a No. 2 dumbbell type and subjected to a tensile test at a crosshead speed of 300 mm / min in an atmosphere of 25 ° C. using a Tensilon RTM-100 type testing machine manufactured by Orientec.

(5) Breaking elongation of dry film by styrene-butadiene-ethylene unsaturated acid monomer copolymer latex Solid weight of polyacrylic acid soda to styrene-butadiene-ethylene unsaturated acid monomer copolymer latex Add at a rate of 0.5%, mix, apply on a glass plate and dry at room temperature for 1 day. A film-like sample (thickness of about 0.5 mm) was further heated at 120 ° C. for 15 minutes to obtain a dry latex film. This was punched out with a No. 2 dumbbell type, and a tensile test was performed at a crosshead speed of 300 mm / min in an atmosphere of 25 ° C. using a Tensilon RTM-100 type testing machine manufactured by Orientec.

(6) Fatigue resistance in rubber (retention rate)
It was evaluated according to JIS-L1017 (2002) Annex 1 2.2.2 disk fatigue strength (Goodrich method). Two treatment cords are embedded in tire rubber and vulcanized at 150 ° C. for 30 minutes to produce a rubber composite. The test piece was subjected to deformation with compression of 6.3% and extension of 12.6% for 1 cycle for 48 hours at 2600 cycles / minute, 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.

(7) Tire high speed durability After finishing the durability performance test specified in JIS D4230 (1998) 6.3 with a drum tester, the tire was destroyed by increasing the speed in units of 10 km / h every 30 minutes. The distance traveled was measured. For the evaluation, a nylon 66 treated cord (nylon 66, 1400T / 2, 37 × 37 (t / 10 cm), elongation at 7.8% at 2 cN / dTex) conventionally used for a cap ply was applied to the cap ply. The tire evaluation results are indicated by an index of 100. A larger index value means higher speed durability.

(8) Tire road noise A pneumatic radial tire with a tire size of 195 / 65R15 was manufactured, and the following tests were performed. Near a narrow band of 240 Hz via a sound collecting microphone installed in the driver's seat at the window-side ear position while the tire is filled with air pressure of 200 kPa, mounted on a passenger car with a displacement of 2000 cc and running on a rough road at a speed of 60 km / h. The sound pressure level at the peak value of the air column resonance sound was measured, and road noise was evaluated from the measured value. For the evaluation, a nylon 66 treated cord (nylon 66, 1400T / 2, 37 × 37 (t / 10 cm), elongation at 7.8% at 2 cN / dTex) conventionally used for a cap ply was applied to the cap ply. The tire evaluation results are indicated by an index of 100. The smaller the index value, the lower the road noise and the better.

(9) Glass transition temperature (Tg) of styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex
It measured using the differential scanning calorimeter apparatus (DSC-50: Shimadzu Corporation make). 10 mg of latex dried at room temperature in advance was sealed in a predetermined aluminum pan, heated from -50 ° C. to 100 ° C. at a rate of 5 ° C./min, and the glass transition temperature of each latex was measured.

[Examples 1-6, Comparative Examples 1-5]
Oxazoline group-containing acrylic / styrene copolymer emulsion (“Epocross” K2030E (Tg = 50 ° C., Nippon Shokubai Co., Ltd.)), glycerol polyglycidyl ether type epoxy resin (“Denacol” EX614B (manufactured by Nagase Kasei Co., Ltd.)), Vinylpyridine-styrene-butadiene rubber latex (2518FS (manufactured by Nippon Zeon)), styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex ("Nalstar" SR-100 (manufactured by Nippon A & L)), styrene- Butadiene-ethylenically unsaturated acid monomer copolymer latex ("Nalstar" SR-104 (manufactured by Japan A & L)), Styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex ("Nalstar" SR-108) (Japan A & L)), block isocyanate The compounds ("Elastoron" BN69 (Daiichi Kogyo Seiyaku Co., Ltd.)) were mixed at a solid content weight ratio shown in Tables 1 and 2, respectively, to obtain an adhesive having a total solid content of 5.0% by weight (first Processing agent). In addition, the symbol content in Tables 1-2 is as showing below.
A: Mixing ratio of oxazoline group-containing acrylic / styrene copolymer emulsion (parts by weight)
B: Blending ratio of glycerol polyglycidyl ether (parts by weight)
C1: Compounding ratio (parts by weight) of vinylpyridine-styrene-butadiene rubber latex (RFL)
C2 to C4: blending ratio of styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex (parts by weight)
D: Blending ratio of blocked isocyanate compound (parts by weight)

  The durometer hardness, tensile strength, and elongation at break of the dried film by the first treating agent were measured. The results are shown in Tables 1-2.

  Resorcin / formalin condensate by mixing in the presence of caustic soda at a molar ratio of resorcin / formalin in the presence of caustic soda to a solids concentration of 10% and aging for 2 hours Got. Next, this initial condensate (RF), vinylpyridine-styrene-butadiene rubber latex (PYRATEX-LB (manufactured by A & L Japan)) and styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex (SR100 (Japan) A / L)) (solid weight ratio of 100/20) (L) was mixed at a ratio of RF / L = 1/5 (solid weight ratio) and aged for 24 hours. Furthermore, 20 parts of the chloro-modified resorcin / formaldehyde initial condensate (“Denabond-E” (manufactured by Nagase Kasei Co., Ltd.)) was mixed with 100 parts by weight of the solid content of the resorcin / formalin latex and further aged for 20 hours. did. This mixture was diluted with water to obtain an adhesive having a solid content of 15% (second treatment agent).

The latex “styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex” had the following glass transition temperature and elongation at break of the dry film.
C2: SR-100 (glass transition temperature: 25 ° C., elongation at break: 25%)
C3: SR-104 (glass transition temperature: 3 ° C., elongation at break: 450%)
C4: SR-108 (glass transition temperature: −9 ° C., elongation at break: 300%)
Two polyester multifilament yarns of 1100 dTex (“Tetron” 1100-240-705M manufactured by Toray Industries, Inc.) are twisted with a twist number of 47 times / 10 cm for the lower twist and 47 times / 10 cm for the upper twist, did.

  The unprocessed code is immersed in the first processing agent using a computer treater processor (CA Ritzler Co., Ltd.), then dried at 120 ° C. for 2 minutes (dry processing), and subsequently at 240 ° C. for 1 minute. Heat treatment (hot treatment) was performed. Subsequently, after being immersed in the second treatment agent, it is dried at 120 ° C. for 2 minutes (dry treatment), followed by heat treatment at 240 ° C. for 0.5 minutes (hot treatment), and further heat treatment at 240 ° C. for 0.5 minutes. (Normalization processing) was performed.

  After the obtained treated cord was embedded in unvulcanized rubber and vulcanized, T-initial adhesive strength and T-heat resistant adhesive strength were measured. The results are shown in Table 1 (Example 1+ Comparative Examples 1 to 5) and Table 2 (Examples 1 to 6). In addition, Tables 1 and 2 also show the results of producing tires with the obtained cords and conducting tire evaluations.

  As shown in Tables 1 and 2, in the case of Examples 1 to 6 according to the present invention, the heat resistant adhesiveness and fatigue resistance in rubber are higher than those of conventional polyester fibers for reinforcing rubber (Comparative Examples 1 to 5). Further, it can be seen that the tire cap ply material has high-speed durability and good road noise.

  As described above, the polyester fiber cord for rubber reinforcement of the present invention is excellent in heat-resistant adhesion and heat-resistant strength retention, and has practically sufficient fatigue resistance, such as conventional tire carcass materials, hoses and belts. When used as a rubber material, it can withstand severe use for a long period of time and can be suitably used as a cap ply member of a tire that could not be applied conventionally.

Claims (8)

  A polyester fiber is coated with a first treatment agent containing a compound having an oxazoline group and a rubber latex, and its outer layer is coated with a second treatment agent containing resorcin / formalin / rubber latex (RFL). It is a polyester fiber cord, and the first treatment agent contains 30 to 70% by weight of rubber latex in 100% by weight of the total solid content, and the durometer hardness of the dried film by the first treatment agent Is a polyester fiber cord for rubber reinforcement, wherein the durometer hardness after heat-treating the dry film of the first treatment agent at 170 ° C. for 70 minutes is A50 to A90.   The breaking elongation of the dry film by the first treating agent is 300% to 1000%, and the breaking elongation after heat-treating the dry film by the first treating agent at 170 ° C. for 70 minutes is 150% to 700%. The polyester fiber cord for rubber reinforcement according to claim 1, wherein the polyester fiber cord is for rubber reinforcement.   The tensile strength of the dry film by the first treatment agent is 1 MPa to 6 MPa, and the tensile strength after the heat treatment of the dry film by the first treatment agent at 170 ° C. for 70 minutes is 2 MPa to 7 MPa. The polyester fiber cord for rubber reinforcement according to claim 1 or 2.   In 100 parts by weight of the total solid content of the rubber latex contained in the first treatment agent, a styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex having a glass transition temperature (Tg) of 0 ° C. to 35 ° C. The polyester fiber cord for rubber reinforcement according to any one of claims 1 to 3, which is contained in an amount of 10 to 80 parts by weight.   The rubber fiber-reinforced polyester fiber cord according to claim 4, wherein the rupture elongation of the dry film by the styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex is 5% to 400%.   A styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex having a glass transition temperature (Tg) of 0 ° C. to 35 ° C. is included in resorcin / formalin rubber latex (RFL) as the second treatment agent. The polyester fiber cord for rubber reinforcement according to any one of claims 1 to 5.   The resin adhesion amount of the coating film by the first treatment agent is 1 to 4% by weight, the resin adhesion amount of the coating film by the second treatment agent is 1 to 4% by weight, and the coating film by the first treatment agent and the second 7. The polyester fiber cord for rubber reinforcement according to any one of claims 1 to 6, wherein the total resin adhesion amount of the coating film by the treatment agent is 2 to 6% by weight.   A tire comprising the polyester fiber cord for reinforcing rubber according to any one of claims 1 to 7 as a cap ply member.