JP5169640B2 - Polyester fiber cord for rubber reinforcement - Google Patents

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. The present invention relates to a polyester fiber cord for reinforcing rubber having a level of practically no problem, and particularly suitable for a cap ply cord of a radial tire.

  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 embedded in a rubber product, the polyester fiber is thermally deteriorated in a high temperature environment. The chemical thermal degradation is affected 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. The amine is decomposed or hydrolyzed by amine compounds, low molecular weight compounds generated by oxidative degradation of the rubber itself, water molecules, water 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 and cannot be used.

  When the polyester fiber is decomposed by amine 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, it has such drawbacks, but it has high strength, high elastic modulus, excellent thermal dimensional stability, improved fatigue resistance and adhesion, and tire manufacturing. Coupled with technological improvements, in recent years it has been used as the carcass material for most passenger car radial tires. However, since it has the above-mentioned essential drawbacks, the heat generated during high-speed running of tires is hard to be trapped and chemically deteriorated, and it is currently used only for carcass materials for passenger cars with relatively small tire sizes. is there. Only a small portion of large tires such as trucks and buses are used. Generally, polyester fiber cords are not used for trucks, bus tires, aircraft tires, large passenger car tires, racing car tires, and the like.

  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 the cap ply cord generates heat and becomes higher in temperature than the carcass portion, nylon 66 fibers that cannot withstand use with conventional polyester cords and have excellent adhesion at high temperatures are used.

  However, since a high elastic modulus is preferable as a characteristic of the cap ply cord, a polyester fiber is preferable as a fiber material, and the polyester fiber is advantageous in terms of cost compared to nylon 66 fiber. There has been a strong demand for the development of usable polyester fiber cords. In order to achieve this, first of all, a great improvement in heat-resistant adhesiveness and an improvement in heat-resistant and strong retention are required.

Patent Documents 1 to 4 are disclosed as techniques for improving heat-resistant adhesion of polyester fibers.
Patent Document 1 discloses a method of treating polyester fibers with (A) a treatment liquid containing a carrier and (B) a treatment liquid containing a blocked isocyanate aqueous solution and then treating the polyester fiber with an RFL containing an epoxy compound.

  Patent Document 2 discloses a treatment method in which a polyester fiber to which a polyepoxide compound has been applied in advance is subjected to multistage treatment of one stage or two or more stages by a treatment liquid containing three components of blocked isocyanate, epoxy compound, and RFL. ing.

  Patent Document 3 discloses a technique for treating polyester fibers with a treatment liquid containing a thermoplastic polymer, a heat-reactive aqueous urethane, and an epoxy compound.

  Patent Document 4 is a cord obtained by treating a polyester fiber with a treatment liquid containing a thermoplastic polymer, a heat-reactive water-based urethane, and an epoxy compound, and has a modulus of elasticity in a 160 ° C. atmosphere equal to or higher than a predetermined modulus. Is disclosed.

Although the above-mentioned patent document techniques show improvement in heat-resistant adhesion and heat-resistant strength retention at high temperatures compared to conventional polyester fiber bonding methods, they are not practically sufficient or fatigue resistance is not sufficient. It was a thing. 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 the object of the present invention.
JP 2006-2327 A (Claims) JP 2006-274529 A (Claims) JP 2001-19927 A (Claims) Japanese Patent Laying-Open No. 2005-112065 (Claims)

  The problems of the present invention are not achieved by the above-described prior art, have high elastic modulus, and improved heat-resistant adhesion and heat-resistant strength retention between polyester fiber and rubber when exposed to high temperatures, and An 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.

The present invention employs the following means in order to solve such problems. That is,
(1) A polyester fiber is coated with a first treatment agent containing at least three types of (A) a compound containing an oxazoline group, (B) an epoxy compound, and (C) a rubber latex, and resorcin / formalin / rubber as an outer layer thereof. A polyester fiber cord for reinforcing rubber formed by coating with a second treatment agent containing latex (RFL), wherein the first treatment agent comprises (A) an oxazoline group with a total solid content of 100% by dry weight. The compound contains 10 to 50% by weight, (B) the epoxy compound contains 20 to 60% by weight, and (C) the rubber latex contains 30 to 70% by weight. A polyester fiber cord for reinforcing rubber having a breaking elongation of 150 to 500% after heat treatment for 70 minutes.
(2) The rubber-reinforced polyester fiber cord according to (1), wherein the rubber-reinforced polyester fiber cord has a Gurley cord hardness of 0.5 mg / dTex to 6.0 mg / dTex.
(3) The rubber latex (C) in the first treatment agent contains one or more types of rubber latex, and the glass transition temperature (Tg) is 0 ° C. to 35 in 100 parts by weight of the total solid content of the rubber latex. The polyester fiber cord for rubber reinforcement as described in (1) or (2) above, wherein 10 to 80 parts by weight of styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex having a temperature of 0 ° C. is contained.
(4) Any of the above (1) to (3), wherein the rupture elongation of the dry film by the styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex is 5% to 400%. A polyester fiber cord for reinforcing rubber as described in 1.
(5) The rubber fiber-reinforced polyester fiber cord according to any one of (1) to (4), wherein the cord satisfies the following physical properties.
(A) Strength: 5.0 to 7.0 cN / dTex
(B) Intermediate elongation: 2.0 to 4.0%
(C) 150 ° C. × 30 minutes dry heat shrinkage: 2.0 to 6.0%
(6) The polyester fiber cord for rubber reinforcement has a first bath hot stretch tension of 0.70 to 2.0 cN / dTex, and a second bath normalizing tension of 0.1 to 1.2 cN / dTex. The rubber fiber-reinforced polyester fiber cord according to any one of (1) to (5), which is treated.
(7) 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 first treatment agent The rubber reinforcing polyester fiber cord according to any one of the above (1) to (6), wherein the total resin adhesion amount of the coating by the coating and the coating by the second treatment agent is 2 to 6% by weight.
(8) The RFL of the second treatment agent includes a styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex having a glass transition temperature (Tg) of 0 ° C. to 35 ° C. The rubber fiber-reinforced polyester fiber cord according to any one of (1) to (7).
(9) A tire obtained by using the polyester fiber cord for rubber reinforcement according to any one of (1) to (8) 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 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.

  In addition, the polyester fiber of the present invention may have been previously provided with a polyepoxide compound 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 emulsified or dissolved 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 deteriorates, 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 for reinforcing rubber according to the present invention is coated with a first treatment agent containing (A) a compound containing an oxazoline group, (B) an epoxy compound, and (C) a rubber latex, and resorcin / formalin / rubber as an outer layer thereof. It is coated with a second treatment agent containing latex (RFL).

  The compound containing an oxazoline group (A) used in the present invention is a compound containing 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. Say. 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.

  The (B) 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.

  Examples of the (C) 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, and chloroprene rubber. Latex, chlorosulfonated rubber latex, ethylene / propylene / diene rubber latex and the like can be mentioned, and these can be used alone or in combination. Especially, it is preferable from a viewpoint of heat resistant adhesive improvement that a styrene-butadiene-ethylenic unsaturated acid monomer copolymer latex is contained.

  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 (C) of 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 the heat-resistant adhesion is further improved. From the viewpoint of making the total content of solids of styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex and other rubber latex 100 parts by weight, styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex It is preferable to add so that 10-80 weight part (dry weight part) may be contained. Although it does not specifically limit as another rubber latex, A vinylpyridine * styrene * butadiene rubber latex can be used conveniently.

  The polyester fiber cord of the present invention includes (A) a compound containing an oxazoline group, (B) an epoxy compound, and (C) a coating with a first treatment agent containing a rubber latex in a predetermined mixing ratio, and further including RFL in its outer layer. It is characterized by having a coating with the second treatment agent. That is, the polyester fiber cord for reinforcing rubber of the present invention inhibits the adhesion reaction between the polyester fiber, the resorcin / formaldehyde initial condensate and the rubber latex, and the adhesion reaction between the resorcin / formaldehyde initial condensate, the rubber latex and the rubber. Without penetration of the low molecular weight amine compound or water molecule into the polyester cord, and as a result, improved heat-resistant adhesion and heat-resistant and strong retention are achieved.

  The polyester fiber cord for rubber reinforcement of the present invention is coated with a first treatment agent containing (A) a compound containing an oxazoline group, (B) an epoxy compound, and (C) a rubber latex. The ratio of the compound containing the (A) oxazoline group to the solid content is required to be 10% by weight or more as a lower limit in dry weight, and preferably 20% by weight or more. Moreover, as an upper limit, it is required that it is 50 weight% or less, Preferably it is 40 weight% or less. If it is less than 10% by weight, the adhesive strength may be insufficient, and if it exceeds 50% by weight, the cord may become hard and fatigue resistance may deteriorate. Moreover, the ratio of the (B) epoxy compound with respect to the total solid of the first treating agent needs to be 20% by weight or more as a lower limit in dry weight, and preferably 30% by weight or more. Moreover, as an upper limit, it is required that it is 60 weight% or less, Preferably it is 50 weight% or less. If it is less than 20% by weight, the adhesive strength may be insufficient, and if it exceeds 60% by weight, the cord becomes hard and fatigue resistance may be deteriorated. Furthermore, the ratio of the (C) rubber latex needs to be 30% by weight or more as a lower limit in dry weight, preferably 40% by weight or more, and more preferably 45% by weight or more. Moreover, as an upper limit, it is required that it is 70 weight% or less, Preferably it is 60 weight% or less. If it is less than 30% by weight, the flexibility of the cord may be insufficient, and if it exceeds 70% by weight, the adhesion may be insufficient.

  Moreover, the elongation at break after heat-treating the coating film of the first treating agent used in the present invention at 170 ° C. for 70 minutes needs to be 150 to 500%, preferably 200 to 400%. If the breaking elongation is outside this range, the fatigue resistance 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 kind 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 in 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, and 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 other It is preferable to use it in combination with one.

  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 is preferably 1: 3 to 1: 8 in terms of solids weight ratio, and is in the range of 1: 4 to 1: 6. More preferably. Outside this range, the adhesion may be insufficient. Further, the blending ratio of resorcin / formaldehyde / latex and the phenolic compound is preferably 10: 1 to 10: 5, more preferably 10: 2 to 10: 4 in terms of solid content. 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 condensate 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 compounding ratio of (P) chloro-modified resorcin represented by the general formula (I) and resorcin / formalin / rubber latex (RFL) is P / RFL = 1/1 to 1/5 in terms of solids 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.

Moreover, it is preferable that the said polyester fiber cord is a twisted yarn cord to which the lower twist and the upper twist were given. 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, and 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. If the upper twist coefficient is outside the preferred range, the adhesive strength after high temperature exposure may be reduced, and 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)

  Further, the Gurley cord hardness of the polyester fiber cord of the present invention is preferably 0.5 mg / dTex to 6.0 mg / dTex, more preferably 1.0 mg / dTex to 5.5 mg / dTex. If the cord is less than 0.5 mg / dTex, the adhesion to the rubber may be insufficient, and if it exceeds 6.0 mg / dTex, the fatigue resistance in the rubber may be deteriorated. The Gurley cord hardness can be adjusted by the type of drug mixed with the first treatment agent, the mixing ratio thereof, the type of drug of the second treatment agent, the mixing ratio thereof, the amount of resin adhered to the coating by each treatment agent, the heat treatment conditions, etc. it can.

  The method for adjusting the Gurley cord hardness is not particularly limited. For example, the Gurley cord hardness can be reduced by reducing the resin adhesion amount of the first treatment agent or the second treatment agent or the total resin adhesion amount thereof. In addition, the Gurley cord hardness can be improved by increasing the resin adhesion amount of the first treatment agent or the second treatment agent or the total resin adhesion amount thereof. Furthermore, the Gurley cord hardness can be reduced by reducing the heat treatment temperature and / or the heat treatment time during the heat treatment in the dipping step described later, and the heat treatment temperature and / or the heat treatment time can be increased. Gurley cord hardness can be improved. At this time, in particular, changing the heat treatment temperature and / or the heat treatment time in the hot treatment and normalization treatment described later may have a great effect of adjusting the Gurley cord hardness. For compounded drug types, for example, the Gurley cord hardness can be decreased by increasing the amount of rubber latex mixed, while the Gurley cord hardness is improved by increasing the amount of thermosetting resin mixed. Can be made. Here, the thermosetting resin is a resin that undergoes polymerization to form a polymer network structure when heated, and does not return to the original monomer by curing. For example, phenol resin, resorcin / formalin resin, melamine resin , Urea resin, unsaturated polyester resin, alkyd resin, reactive polyurethane (including blocked polyisocyanate), thermosetting polyimide, epoxy resin and the like.

  The strength of the polyester fiber cord of the present invention is preferably 5.0 to 7.0 cN / dTex, more preferably 5.3 to 6.7 cN / dTex. When it is less than 5.0 cN / dTex, it is impossible to bear stress in the tire circumferential direction as a cap ply application. A cord of 7 cN / dTex or more cannot provide a practical tire cord from the viewpoint of production stability and cost of raw yarn. Here, the cord strength is a value obtained by dividing the cord strength by a reference fineness in cord configuration (for example, 2200 dTex if two original yarns of 1100 dTex are twisted together).

  Further, as an index of the elastic modulus of the tire cord, an elongation at a load of 2.0 cN / dTex (hereinafter referred to as an intermediate elongation) is used, and the polyester fiber cord of the present invention is 2.0 to 4.0%. Preferably there is. More preferably, it is 2.1 to 3.8%, and further preferably 2.2 to 3.6%. If the intermediate elongation is less than 2.0%, the bending fatigue resistance in rubber may be deteriorated. If it exceeds 4.0%, when used as a cap ply cord, Road noise may worsen.

  Furthermore, the dry heat shrinkage (150 ° C. × 30 minutes treatment, hereinafter referred to as dry yield) of the polyester fiber cord of the present invention is preferably 2.0 to 6.0%. More preferably, it is 2.2 to 5.8%, and further preferably 2.4 to 5.6%. If the dry yield is less than 2.0%, the cord shrinkage due to heat during tire shaping is small, and the tightenability as a cap ply cord may be deteriorated, which may lead to cord peeling during running. When the dry yield exceeds 6.0%, the cord contraction during tire shaping is large, the bite into the rubber increases, and may contact the belt layer disposed under the cap ply, resulting in a deterioration in fatigue resistance. Sometimes.

  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, a method for producing the rubber fiber-reinforced polyester fiber cord of the present invention will be described. In the method for producing a rubber reinforcing polyester fiber cord to which an adhesive is applied, the rubber reinforcing polyester fiber cord of the present invention is prepared by (A) a compound containing an oxazoline group, (B) an epoxy compound, (C) It is preferable to obtain by providing the 1st processing agent containing rubber latex, and providing the 2nd processing agent containing resorcinol, formalin, rubber latex in the 2nd 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) a compound containing an oxazoline group, (B) an epoxy compound, and (C) a rubber latex is provided. It is preferable to apply a second treatment agent containing resorcin, formalin, and rubber latex at the bath.

  In the first bath, (A) a compound containing an oxazoline group, (B) an epoxy compound, and (C) a first treatment agent containing a rubber latex is prepared by adjusting the adhesive containing the component as an aqueous solution or water dispersion. It is performed by immersing the polyester fiber raw cord or raw cord bran in the dipping solution, 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, the amount of solid content will be too large, the cord will become hard, and fatigue resistance may be reduced, which is not preferable.

  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 coating 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 the first bath dip solution is applied as described above, a second treatment agent containing resorcin, formalin, and rubber latex 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 off with compressed 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. This is not preferable because the coating film formed by the treatment agent is deteriorated to lower the adhesive force, or the polyester fiber is thermally deteriorated to be strongly reduced.

  In the above dip treatment, the tension during the hot treatment during the first bath treatment (first bath hot stretch tension) is 0.70 cN / dTex to 2.0 cN / dTex, and the normalization treatment during the second bath treatment. The tension (second bath normalizing tension) is preferably 0.1 cN / dTex to 1.2 cN / dTex. More preferably, the first bath hot stretch tension is 0.80 cN / dTex to 2.0 cN / dTex, and the second bath normalizing tension is 0.2 cN / dTex to 1.0 cN / dTex. If it is less than this tension, it is difficult to sufficiently improve the elastic modulus of the cord. If this tension is exceeded, the quality of the cord may be deteriorated, such as the occurrence of cord scuffing. However, the method for increasing the elasticity of the cord is not limited to this, and other methods such as lowering the twist of the cord may be used.

  The polyester fiber cord for rubber reinforcement of the present invention produced by the two-bath dip method includes: (A) a compound containing an oxazoline group, (B) an epoxy compound, (C) a first treating agent layer containing a rubber latex, This is a polyester fiber cord for reinforcing rubber comprising a second treatment agent layer containing formalin rubber latex. 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.

  In the polyester fiber cord for reinforcing rubber of the present invention, the use of a compound containing an oxazoline group improves the adhesion to the polyester surface, and the reaction between the epoxy compound and the compound containing an oxazoline group results in a resin having a high crosslinking density. By covering the polyester fiber, it is considered that the heat-resistant adhesiveness is improved by preventing the amine compound generated from the rubber from entering the inside of the fiber. Moreover, it is considered that the flexibility of the resin is imparted by mixing rubber latex, and the bending fatigue resistance is improved. The present invention has found that a compound containing an oxazoline group, an epoxy compound, and a rubber latex are mixed at a predetermined ratio in order to achieve both heat resistant adhesion and bending fatigue resistance, and in particular, a cap ply member for a radial tire. Can be suitably used.

  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) Cord properties (Strength, strength, cutting elongation, intermediate elongation)
According to JIS L-1017 (2002) 8.5, after leaving for 24 hours or more in a temperature-controlled room at 20 ° C. and 65% RH, the tensile strength was measured with a Tensilon tensile tester. The intermediate elongation of the cord was 2.0 cN / dtex stress elongation.

(3) Code properties (dry heat shrinkage)
It measured by the method of JIS L1017 (2002) 8.10 (B method). The heat treatment was performed at 150 ° C. for 30 minutes.

(4) Fineness According to JIS L-1017 (2002) 8.3, the fineness was measured after standing for 24 hours or more in a temperature-controlled room at 20 ° C. and 65% RH.

(5) T-initial adhesive strength and T-heat resistant adhesive strength This indicates the adhesive strength between the treated 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): 80 (parts by weight)
SBR (JSR1501): 20 (parts by weight)
RF carbon black: 50 (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).

(6) Gurley cord hardness Cut the treated cord into a length of 1m, tied one end with a metal hook, and tied the other end with a 300g weight, under an environment adjusted to a temperature of 25 ° C and a relative humidity of 40%. Then, it was suspended in the air for 24 hours to make the cord vertical, and a measurement sample was obtained.

  This was cut into a specified sample length to obtain a test piece, and measured with a “Gurley's stiffness tester” manufactured by Yasuda Seiki Co., Ltd. FIG. 1 is a perspective view of “Gurley's stiffness tester”, and FIG. 1 is a movable arm A, 2 is a pendulum B, 3 is a level, 4 is a level screw, 5 is a chuck, 6 is a test piece, 7 is a bearing (fulcrum), 8 is a scale plate, 9 is a weight, 10 is a switch button , 11 is a rotating rod, and 12 is a needle. The test piece 6 is attached and measured by (a) fixing the chuck 5 at a set position according to the sample length, and attaching the test piece 6. (A) A load arbitrary setting hole is provided at the lower part of the rotating rod 11 (below the bearing 7) from the shaft by 1 inch (W1 in FIG. 1), 2 inches (W2 in FIG. 1), and 4 inches (in FIG. 1). Since it is in the position of W3), the weight of the load and the position of the hole are set according to the flexibility of the test piece 6. In this case, the load and the position of the hole must be selected so that the needle 12 indicates 2-4 on the scale plate 8. (C) When the setting suitable for the test piece 6 is completed, the drive button is pushed, the drive shaft is moved left and right, and the numerical value of the scale plate 8 pointed to by the needle 12 is read to 0.1 unit. (D) For each test piece 6, determine the average value of one sample by obtaining the value of 20 test pieces in total, 10 test pieces 6 once on the left and right.

The calculation method is as follows. The average value of each measured value is calculated by the following formula.
Gurley cord hardness (mg / dTex) = R × {(W1 × 1) + (W2 × 2) + (W3 × 4)} / 5 × L ² /W×19.8/T
However,
R: Average value of measured values W1: Load applied to load position (hole) of 1 inch (unit: g)
W2: Load applied to the load position (hole) of 2 inches (unit: g)
W3: Load applied to the load position (hole) of 4 inches (unit: g)
L: Sample length—1 / 2 inch (inch)
W: Width of test piece 6 (inch)
T: Fineness (dTex)

(7) Breaking elongation after heat treatment at 170 ° C. for 70 minutes of the coating with the first treatment agent An aqueous dispersion of the treatment agent was applied to a glass plate so that the thickness of the coating after drying was 0.5 mm, and at room temperature After drying for 72 hours, it was peeled from the glass plate and heat-treated in a 170 ° C. oven for 70 minutes. 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.

(8) Breaking elongation of dry film by styrene-butadiene-ethylenic unsaturated acid monomer copolymer latex Solid weight of polyacrylic acid soda to styrene-butadiene-ethylenically 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.

(9) 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.

(10) Tire high-speed durability After completing the high-speed durability test specified in JIS D4230 with a drum testing machine, the speed is increased in increments of 10 km / h every 30 minutes to determine the running distance until the tire breaks. It 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.

(11) Tire road noise A pneumatic radial tire having a tire size of 195 / 65R15 was manufactured, and the following tests were performed. The in-vehicle noise (db) was measured when the tire was filled with an air pressure of 200 kPa and mounted on a passenger car with a displacement of 2000 cc and traveled on a rough road surface at a speed of 60 km / h. 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.

(12) 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.

(13) Lower twist coefficient K1, upper twist coefficient K2
It calculated | required with the following formula.
K = T × D ^1/2 , T: Number of twists per unit length (times / 10 cm), D: Fineness The fineness was determined by the method described in (4). The number of twists per unit length was measured as follows. According to the method described in JIS R7601, both ends of the cord to be measured were gripped and attached to a clamp of a twisting machine so that the interval was 500 mm. One clamp was fixed, the other clamp was rotated, the number of rotations until the twist was completely unwound was measured, and the number of twists of the cord (times / 10 cm) was calculated from the doubled value.

(Examples 1-9, Comparative Examples 1-7)
(A) Oxazoline group-containing acrylic / styrene copolymer emulsion ("Epocross" K2030E (manufactured by Nippon Shokubai Co., Ltd.)), (B1) Glycerol polyglycidyl ether ("Denacol" EX313 (manufactured by Nagase Kasei)), (B2 ) Cresol novolac type epoxy resin ("Denacol" EM150 (manufactured by Nagase Kasei Co., Ltd.)), (C1) vinylpyridine-styrene-butadiene rubber latex (PYRATEX-LB (manufactured by Japan A & L)), (C2) styrene-butadiene-ethylene -Based unsaturated acid monomer copolymer latex ("Nalstar" SR-100 (manufactured by Japan A & L)), (C3) styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex ("Nalstar" SR-104) (Japan A & L)), (C4) Styrene-Butaje -Ethylene-based unsaturated acid monomer copolymer latex ("Nalstar" SR-108 (manufactured by Japan A & L)), (D) block isocyanate compound ("Elastoron" BN27 (Daiichi Kogyo Seiyaku Co., Ltd.)), It mixed by the solid content weight ratio shown to Tables 1-3, and obtained the adhesive agent of the total solid amount of 5.0 weight% (1st processing agent). The symbol contents in Tables 1 to 3 are as shown below.
A: Mixing ratio of oxazoline group-containing acrylic / styrene copolymer emulsion (parts by weight)
B1: Blending ratio of glycerol polyglycidyl ether (parts by weight)
B2: Blending ratio of cresol novolac type epoxy resin (parts by weight)
C1: Mixing ratio (part by weight) of vinylpyridine-styrene-butadiene rubber latex
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)

  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)) was mixed with 100 parts by weight of the solid content of the resorcin / formalin / latex, and further aged for 20 hours. . 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. (In Example 7, an untreated cord was obtained by twisting the yarn with a twist number of 25 times / 10 cm for the lower twist and 25 times / 10 cm for the upper twist.)

  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. Here, the tension at the first bath hot treatment (hot stretch tension) and the tension at the second bath normalization treatment (normalizing treatment tension) were processed according to the numerical values shown in Tables 1 to 3, respectively.

  Various physical properties of the obtained treatment cord and embedding and vulcanization in unvulcanized rubber were measured, and then T-initial adhesive strength and T-heat resistant adhesive strength were measured. The results are shown in Tables 1-3.

  The base twist coefficient K1 of Example 7 was 830, and the top twist coefficient K2 was 1170. The base twist coefficient K1 of the other Examples and Comparative Examples was 1560, and the top twist coefficient K2 was 2210.

  Moreover, a tire is produced with the obtained cord, and the results of the tire evaluation are shown in Tables 1 to 3 together.

  As in the results of Tables 1 to 3, in the case of Examples 1 to 9 according to the present invention, the heat-resistant adhesiveness in rubber is better than the conventional rubber reinforcing polyester fibers (Comparative Examples 1 to 7). Further, it can be seen that the tire cap ply material has high speed durability and good road noise, and is in rubber.

It is a perspective view of "Gurley's stiffness tester". It is a principal part enlarged view of FIG.

Explanation of symbols

1 Movable arm A
2 Pendulum B
3 Level 4 Level screw 5 Chuck 6 Test piece 7 Bearing 8 Scale plate 9 Weight 10 Switch button 11 Rotating rod 12 Needle

Claims (9)

  The polyester fiber is coated with a first treatment agent containing at least three types of (A) a compound containing an oxazoline group, (B) an epoxy compound, and (C) a rubber latex, and further, resorcin / formalin rubber latex (RFL) as an outer layer thereof. The first treatment agent comprises 100% by weight of the total solid content by dry weight, and (A) the compound containing an oxazoline group is 10 -50% by weight, (B) 20-60% by weight of epoxy compound, (C) 30-70% by weight of rubber latex, and the coating with the first treatment agent was heat treated at 170 ° C. for 70 minutes A polyester fiber cord for reinforcing rubber having a later breaking elongation of 150 to 500%.   The polyester fiber cord for rubber reinforcement according to claim 1, wherein the Gurley cord hardness of the polyester fiber cord for rubber reinforcement is 0.5 mg / dTex to 6.0 mg / dTex.   The (C) rubber latex in the first treatment agent contains one or more types of rubber latex, and the glass transition temperature (Tg) is 0 ° C. to 35 ° C. in 100 parts by weight of the total solid content of the rubber latex. The polyester fiber cord for rubber reinforcement according to claim 1 or 2, wherein 10 to 80 parts by weight of styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex is contained.   The polyester fiber cord for rubber reinforcement according to claim 3, wherein the rupture elongation of the dry film by the styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex is 5% to 400%. The said cord satisfy | fills the following physical property, The polyester fiber cord for rubber reinforcement in any one of Claims 1-4 characterized by the above-mentioned.
(A) Strength: 5.0 to 7.0 cN / dTex
(B) Intermediate elongation: 2.0 to 4.0%
(C) 150 ° C. × 30 minutes dry heat shrinkage: 2.0 to 6.0%   The rubber reinforcing polyester fiber cord is treated with a first bath hot stretch tension of 0.70 to 2.0 cN / dTex and a second bath normalizing tension of 0.1 to 1.2 cN / dTex. The polyester fiber cord for rubber reinforcement according to any one of claims 1 to 5, wherein   The amount of resin adhesion of the film by the first treatment agent is 1 to 4% by weight, the amount of resin adhesion of the film by the second treatment agent is 1 to 4% by weight, and the film by the first treatment agent 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 second treatment agent is 2 to 6% by weight.   2. The styrene-butadiene-ethylenically unsaturated acid monomer copolymer latex having a glass transition temperature (Tg) of 0 ° C. to 35 ° C. is contained in the RFL of the second treatment agent. The polyester fiber cord for rubber reinforcement according to any one of?   A tire formed by using the polyester fiber cord for rubber reinforcement according to any one of claims 1 to 8 as a cap ply member.

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