Adhesive composition for organic fiber cords, organic fiber cord-rubber composites, and tires

Abstract

The present invention provides an adhesive composition for organic fiber cords, said adhesive composition being technologically characterized by containing (A) a synthetic rubber latex comprising an unsaturated diene, (B) gelatin and (C) an aqueous compound having a (thermally dissociative blocked) isocyanate group, and by not containing resorcin and formaldehyde. This adhesive composition for organic fiber cords enables the achievement of effects such as: (1) the environmental load is low since resorcin and formaldehyde are not used; (2) in a process where an organic fiber cord is covered with this adhesive composition for organic fiber cords and is subsequently dried and thermally cured, adhesion of this adhesive composition for organic fiber cords to a roll and the like is suppressed, thereby enabling the achievement of good workability; and (3) good adhesion is achieved between an organic fiber cord and a covering rubber composition.

Description

Technical Field

[0001] The present invention relates to an adhesive composition for organic fiber cords that does not contain either resorcinol or formaldehyde, an organic fiber cord-rubber composite using the organic fiber cord coated with the adhesive composition for organic fiber cords, and a tire using the organic fiber cord-rubber composite.

Background Art

[0002] For the purpose of reinforcing rubber products such as tires, an organic fiber cord such as a tire cord made of polyester fiber or the like is adhered to a rubber composition for tires to form an organic fiber cord-rubber composite. For the adhesion, a method is generally used in which the organic fiber cord is coated with an adhesive composition for organic fiber cords, and the adhesive composition for organic fiber cords is co-vulcanized with the rubber composition for tires.

[0003] When coating the organic fiber cord with the adhesive composition for organic fiber cords, particularly when coating with the adhesive composition for organic fiber cords by dipping, it is necessary to reduce the viscosity of the adhesive composition for organic fiber cords until it can be applied by dipping. And since the solvent for adjusting the viscosity of the adhesive composition for organic fiber cords volatilizes in the coating step, it is preferable to use water with a low environmental load as the solvent.

[0004] Generally, an aqueous (water-soluble or water-dispersible) aqueous adhesive composition needs to contain, as a component, a compound having a polar molecular structure. However, on the other hand, polymer materials such as rubber and organic fiber cord substrates to be adhered to have low polarity, and when the difference between the polarity of their surfaces and the polarity of the components contained in the adhesive composition for organic fiber cords becomes large, it becomes difficult to adhere. Therefore, in order to use the aqueous adhesive composition as an adhesive composition for organic fiber cords, the components contained in the aqueous adhesive composition need to have a polarity for being aqueous, while also having a polarity controlled so that the difference from the polarity of the adherend does not cause a decrease in adhesiveness. That is, an aqueous adhesive composition for organic fiber cords having functions that reconcile these contradictions is preferably used.

[0005] Here, regarding the step of coating the organic fiber cord with the adhesive composition for organic fiber cords, an example of the step in the case of immersing the organic fiber cord in the adhesive composition for organic fiber cords will be described with reference to FIG. 1.

[0006] The organic fiber cord 1 runs from unwinding into a dipping bath (dipping tank) 3 containing the adhesive composition 2 for organic fiber cords and is immersed in the adhesive composition 2 for organic fiber cords. Next, the organic fiber cord 4 coated with the adhesive composition 2 for organic fiber cords is lifted from the dipping bath (dipping tank) 3, and excess adhesive composition 2 for organic fiber cords is removed by a squeezing roll 5. Then, further, the organic fiber cord 4 coated with the adhesive composition 2 for organic fiber cords is dried in a drying zone 6 while being conveyed by a roll, heat-cured the resin while applying tension in a hot zone 7 to stretch the cord, and heat-cured the resin while accurately adjusting the tension to achieve the desired strength and elongation physical properties in a normalization zone 8 for normalization, and air-cooled outside the zone. Finally, the organic fiber cord 4 coated with the adhesive composition 2 for organic fiber cords is wound up. In this way, the organic fiber cord is coated with the adhesive composition for organic fiber cords.

[0007] As the adhesive composition for the organic fiber cord, conventionally, an RFL (resorcin - formalin - latex) adhesive composition obtained by aging a mixed solution containing resorcin, formalin, and rubber latex, or an adhesive composition obtained by mixing a specific adhesion promoter with the RFL adhesive composition has been used (see Patent Documents 1 to 4).

[0008] As is well known, in the rubber industry, an adhesive composition composed of an aqueous phenolic resin obtained by mixing a water - dispersible rubber latex component and water - soluble resorcin and formalin and aging them (Patent Document 1) has been found to have a function of achieving both water - based and adhesion to a substrate surface with low polarity such as rubber and organic fiber cord materials that become adherends, and is widely used worldwide. In the RFL adhesive composition, the phenolic resin component composed of the condensate of resorcin and formaldehyde it contains is responsible for the adhesiveness to the organic fiber cord material side, and the rubber latex component it contains is responsible for the adhesiveness to the adherend rubber side by co - vulcanization.

[0009] The reason why resorcin is preferably used here is that resorcin provides a phenolic condensation resin which is a resin type with high adhesiveness to the adherend, and the polar functional group introduced into the phenol ring to obtain water - solubility is a hydroxyl group which has relatively low polarity and is less likely to cause steric hindrance. Therefore, it can provide a resin component with high adhesiveness to the organic fiber substrate side.

[0010] Further, the RFL adhesive composition is prepared by mixing resorcin, formalin, and a rubber latex using rosin acid as an emulsifier for polymerization in the presence of a basic composition and aging. By this aging, the water - soluble resorcin and formaldehyde form a resole - type resorcin - formaldehyde condensate by a resole - type condensation reaction under a base (Patent Document 2), and it is presumed (Non - Patent Document 1) that the rosin acid on the latex surface undergoes addition condensation with the methylol group at the end of the resole - type resorcin - formaldehyde condensate, thereby enhancing the adhesiveness.

[0011] On the one hand, the latex becomes a protective colloid encapsulated by being combined with an aqueous resin. As a result, in the treatment of the adhesive composition by a device such as in FIG. 1, the rubber tackiness of the latex is suppressed, the contamination due to the adhesion of the adhesive composition to the device is reduced, and the RFL adhesive composition can be preferably used.

[0012] Furthermore, in the RFL adhesive composition, in order to achieve both adhesion to water-based and less polar base materials such as rubber and organic fiber cord materials that become adherends, an aqueous (water-dispersible or water-soluble) adhesive promoter has been added.

[0013] As the water-dispersible adhesive promoter, (blocked) isocyanates such as methylene diphenyl diisocyanate having a particle size of 0.01 to 0.50 μm (see Patent Document 3), and water-dispersed particles of phenol-based or novolak-type resins that are water-insoluble such as cresol novolak-type polyfunctional epoxy resins (see Patent Document 4) are used.

[0014] Also, as the adhesive promoter containing a water-soluble group, a sodium hydroxide solution of a novolak condensate obtained by subjecting resorcinol and formaldehyde to a novolak reaction (see Patent Document 5), phenolic resins that dissolve in water in the presence of basic substances such as an ammonium solution of a novolak condensate of chlorophenols and formaldehyde, or an aqueous urethane compound having a (thermally dissociable blocked) isocyanate group and a self-water-soluble group (see Patent Document 6) are used.

[0015] However, in recent years, resorcinol and formaldehyde, which have been used as water-soluble components in RFL adhesive compositions, are required to reduce their usage amounts from the perspective of reducing environmental impact.

[0016] And in order to respond to this, adhesive compositions for organic fiber cords based on a water solvent system that do not contain resorcinol and formaldehyde have been variously studied and proposed.

[0017] For example, an adhesive composition comprising a rubber latex, a blocked isocyanate compound, an epoxide compound, and an amino-based compound as a curing agent (see Patent Document 7), or a urethane resin having a (thermally dissociable blocked) isocyanate group, an epoxide compound, a polymer having an oxazoline group, a basic catalyst having a number average molecular weight of 1,000 to 75,000, and a rubber latex (see Patent Document 8), etc. have been disclosed as adhesive compositions for organic fiber cords that do not contain resorcinol and formaldehyde.

[0018] However, when using an adhesive composition for an organic fiber cord that does not contain resorcinol and formalin as described above, the adhesiveness of the rubber latex measured as the mechanical stability under shear strain of the adhesive liquid becomes high. As a result, for example, in the process of coating the organic fiber cord 1 in FIG. 1 with the adhesive composition 2 for the organic fiber cord and drying and thermosetting it, the adhesion of the adhesive composition 2 for the organic fiber cord to the squeezing roll 5 and the rolls in the drying zone 6 increases, and a new problem occurs that the workability of this process deteriorates.

[0019] Also, the adhesive composition for an organic fiber cord that does not contain resorcinol and formalin as described above * Since crosslinking between the latex component in the coated rubber composition and the resorcinol-formaldehyde condensate in the adhesive composition for the organic fiber cord cannot be obtained in the first place, the adhesiveness is lower than that of the conventional RFL adhesive composition. * It becomes easier to adhere to the above-mentioned apparatus in the process of coating the organic fiber cord with the adhesive composition for the organic fiber cord, and as a result, the coated surface by the adhesive for the organic fiber cord becomes rough, so the adhesiveness decreases. It also had the problem of

[0020] Furthermore, the adhesive composition for an organic fiber cord that does not contain resorcinol and formalin as described above * Causes a decrease in the cord strength of the organic fiber cord coated with the adhesive composition for the organic fiber cord. It also had the problem of

Prior Art Documents

Patent Documents

[0021]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Non - Patent Documents

[0022]

Non - Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0023] The present invention has been made in view of such a situation, (1) By not using resorcinol and formaldehyde, the environmental load is small, (2) By suppressing the adhesiveness of the rubber latex measured as the mechanical stability under shear strain of the adhesive liquid, in the step of coating the organic fiber cord with the adhesive composition for organic fiber cord and drying and thermosetting it, it becomes possible to suppress the adhesion of the adhesive composition for organic fiber cord to a roll or the like, and the workability is good. (3) The organic fiber cord and the coating rubber composition have good adhesiveness. An object of the present invention is to provide an adhesive composition for an organic fiber cord that can achieve the following effects. In addition, an object of the present invention is to provide an organic fiber cord-rubber composite using the organic fiber cord coated with the adhesive composition for an organic fiber cord, and a tire using the organic fiber cord-rubber composite.

Means for Solving the Problems

[0024] In order to solve the above problems, the present inventors have intensively studied the composition of the adhesive for organic fiber cords. As a result, an adhesive composition for an organic fiber cord, which comprises (A) a synthetic rubber latex having an unsaturated diene, (B) gelatin, and (C) an aqueous compound having a (thermally dissociable blocked) isocyanate group, (1) By not using resorcin and formaldehyde, it has less environmental impact. (2) By suppressing the adhesiveness of the rubber latex measured as the mechanical stability under shear strain of the adhesive liquid, it becomes possible to suppress the adhesion of the adhesive composition for the organic fiber cord to a roll or the like in the step of coating the organic fiber cord with the adhesive composition for the organic fiber cord and drying and thermosetting it, and the workability is good. (3) The organic fiber cord and the coating rubber composition have good adhesiveness. It has been found that it is an adhesive composition for an organic fiber cord that solves the above problems, and the present invention has been completed.

[0025] That is, the adhesive composition for an organic fiber cord of the present invention [Item 1] (A) A synthetic rubber latex having an unsaturated diene, (B) Gelatin, and (C) An aqueous compound having a (thermally dissociable blocked) isocyanate group, Including, and Not containing resorcin and formaldehyde, An adhesive composition for an organic fiber cord, characterized by being.

Advantages of the Invention

[0026] According to the present invention, (1) By not using resorcinol and formaldehyde, the environmental load is low, (2) By suppressing the adhesiveness of the rubber latex measured as the mechanical stability under shear strain of the adhesive liquid, it becomes possible to suppress the adhesion of the organic fiber cord to the adhesive composition for organic fiber cord in the step of coating the organic fiber cord with the adhesive composition for organic fiber cord and drying / thermosetting, and the workability is good. (3) The adhesiveness between the organic fiber cord and the coating rubber composition is good. There is provided an adhesive composition for an organic fiber cord that has the following effects. In addition, an organic fiber cord-rubber composite using the organic fiber cord coated with the adhesive composition for an organic fiber cord, and a tire using the organic fiber cord-rubber composite are provided.

Brief Description of the Drawings

[0027]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0028] Hereinafter, embodiments of the present invention will be specifically described. These descriptions are for the purpose of exemplifying the present invention and do not limit the present invention in any way.

[0029] In this specification, when representing a range, unless otherwise specified, the ends of the range are also included within the range.

[0030] The adhesive composition for organic fiber cords of the present invention (A) A synthetic rubber latex having an unsaturated diene, (B) Gelatin, and (C) An aqueous compound having a (thermally dissociable blocked) isocyanate group, includes, and does not contain resorcin and formaldehyde, is characterized by.

[0031] <Organic fiber cord> The organic fiber cord of the adhesive composition for organic fiber cords of the present invention may be used to supplement the strength of rubber articles such as tires. When using the organic fiber cord as a reinforcing material, first, the raw yarn of the spun organic fiber is twisted to form an organic fiber cord. Then, the organic fiber cord is embedded in the rubber that coats the organic fiber cord using the adhesive composition for organic fiber cords and vulcanized and adhered to form an organic fiber cord-rubber composite, and this organic fiber cord-rubber composite is used as a reinforcing member of rubber articles such as tires.

[0032] The material of the organic fiber cord is not particularly limited, and it can be used for synthetic resin fiber materials typified by aliphatic polyamide fiber cords such as polyester, 6-nylon, 6,6-nylon, 4,6-nylon, polyketone fiber cords, and aromatic polyamide fiber cords typified by para-phenylene terephthalamide. Among these, polyester, 6-nylon, and 6,6-nylon are preferable, and polyester is particularly preferable.

[0033] The polyester material is a polymer having an ester bond in the main chain. More specifically, 80% or more of the bonding modes of the repeating units in the main chain are of the ester bond mode. Examples of the polyester are not particularly limited, but those obtained by condensation through an esterification reaction or transesterification reaction between glycols such as ethylene glycol, propylene glycol, butylene glycol, methoxypolyethylene glycol, and pentaerythritol, and dicarboxylic acids such as terephthalic acid, isophthalic acid, and their dimethyl derivatives. The most typical polyester is polyethylene terephthalate.

[0034] The organic fiber cord is preferably an organic fiber cord formed by twisting a plurality of single fiber filaments, particularly for the purpose of reinforcing rubber articles such as tire articles and conveyor belts. Also, the organic fiber cord is preferably an organic fiber cord formed by twisting an upper-twisted single fiber filament and a lower-twisted single fiber filament. In this case, it is more preferable that the twist coefficient of the lower twist is 1,300 or more and 2,500 or less, and / or the twist coefficient of the upper twist is 900 or more and 1,800 or less.

[0035] <(A) Synthetic rubber latex having an unsaturated diene> The "(A) synthetic rubber latex having an unsaturated diene" in the adhesive composition for the organic fiber cord of the present invention refers to a synthetic rubber latex containing an unsaturated diene that is vulcanizable with sulfur.

[0036] In an embodiment of the present invention, an example of the principle of the action exhibited by the above-mentioned "(A) synthetic rubber latex having an unsaturated diene" contained in the adhesive composition for organic fiber cords of the present invention will be described with reference to FIGS. 2 and 3. The synthetic rubber latex 11 having an unsaturated diene is a component for bonding the adhesive layer 32 formed by the adhesive composition 2 for organic fiber cords and the covering rubber composition 33 which is the adherend. The synthetic rubber latex 11 having an unsaturated diene is compatible with the rubber polymer contained in the covering rubber composition 33 which is the adherend, and further forms a rubber co-vulcanization adhesion 21 by the co-vulcanization of the unsaturated diene sites. As a result, the adhesive composition for organic fiber cords of the present invention containing "(A) synthetic rubber latex having an unsaturated diene" is (3) excellent in the adhesiveness between the organic fiber cord and the covering rubber composition, and becomes such.

[0037] Examples of the "(A) synthetic rubber latex having an unsaturated diene" include, but are not limited to, styrene-butadiene copolymer rubber latex, vinyl pyridine-styrene-butadiene copolymer rubber latex, carboxyl group-modified styrene-butadiene copolymer rubber latex, nitrile rubber latex, chloroprene rubber latex and the like. These may be used alone or in combination of two or more. Among them, vinyl pyridine-styrene-butadiene copolymer rubber latex is preferred. Vinyl pyridine-styrene-butadiene copolymer rubber latex is a rubber latex that has been conventionally widely used in adhesive compositions for organic fiber cords and articles such as tires. Also in the adhesive composition for organic fiber cords of the present invention, it brings about a good bond between the adhesive layer and the adherend rubber, and due to the advantages of being relatively flexible and flexible, it enables the deformation of the organic fiber cord without splitting the adhesive layer.

[0038] Further, in the adhesive composition for organic fiber cords of the present invention, the content of the synthetic rubber latex having an unsaturated diene (A) is not particularly limited, but is preferably 25% by mass or more and preferably 80% by mass or less. When it is 25% by mass or more, the compatibility between the rubber polymers of the adherend rubber composition and the rubber latex contained in the adhesive composition for organic fiber cords becomes more appropriate, and the adhesion state of the coating rubber in the organic fiber cord-rubber composite becomes more excellent. Further, when it is 80% by mass or less, it becomes possible to secure a certain amount or more of the resin component contained as another component in the adhesive composition. As a result, the cohesive fracture resistance of the adhesive layer is sufficiently secured, and sufficient adhesiveness can be obtained by making it difficult for fracture to occur within the adhesive layer.

[0039] (A) For the synthetic rubber latex having an unsaturated diene, an emulsifier such as potassium rosinate is dissolved in water, and then the monomer mixture described above is added thereto. Further, electrolytes such as sodium phosphate and peroxide are added as initiators to carry out polymerization. After that, after reaching a predetermined conversion rate, a charge transfer agent is added to stop the polymerization, and further, the remaining monomers are removed to obtain a rubber latex.

[0040] As the emulsifier, one or more of anionic surfactants such as alkali metal salts of fatty acids, alkali metal salts of rosin acids, sodium formaldehyde condensed naphthalene sulfonate, sulfuric acid esters of higher alcohols, alkylbenzene sulfonates, aliphatic sulfonates, or nonionic surfactants such as alkyl ester type, alkyl ether type, and alkyl phenyl ether type of polyethylene glycol are used. Among these emulsifiers, it is preferable to contain a metal salt of rosin acid, and it can be used alone (only one type), or can be used in combination of two or more with other emulsifiers. In the production of the synthetic rubber latex having an unsaturated diene (A) in the examples of the present invention, an alkali metal salt of rosin acid was used alone. Rosin acid is a mixture of resin acids with a similar chemical structure, mainly composed of tricyclic diterpenoids obtained from pine resin and the like. These resin acids have three ring structures, two double bonds, and one carboxyl group. The double bond part reacts with an unsaturated carboxylic acid or the methylol end of a resol-type phenolic resin. They have functional groups rich in reactivity such as esterification at the carboxyl group part. The amount of such an emulsifier used is usually 0.1 to 8 parts by weight, preferably 1 to 5 parts by weight, based on 100 parts by weight of all the monomers used in latex polymerization.

[0041] As the polymerization initiator, for example, water-soluble initiators such as potassium persulfate, sodium persulfate, ammonium persulfate, redox initiators, or oil-soluble initiators such as benzoyl peroxide can be used. In the production of the synthetic rubber latex having (A) an unsaturated diene in the examples of the present invention, potassium persulfate was used.

[0042] As the chain transfer agent, for example, monofunctional alkyl mercaptans such as n-hexyl mercaptan, t-dodecyl mercaptan, n-dodecyl mercaptan, n-octyl mercaptan, n-tetradecyl mercaptan, t-hexyl mercaptan; bifunctional mercaptans such as 1,10-decanedithiol, ethylene glycol dithioglycolate; trifunctional mercaptans such as 1,5,10-candtrithiol, trimethylolpropane tristithioglycolate; tetrafunctional mercaptans such as pentaerythritol tetrakisthiolglycolate; disulfides; halogen compounds such as carbon tetrachloride, carbon tetrabromide, ethylene bromide; α-methylstyrene dimer, terpinolene, α-terpinene, dipentene, allyl alcohol, etc. can be used. These can be used alone or in combination of two or more. Among these chain transfer agents, preferably, alkyl mercaptans are mentioned, and more preferably, n-octyl mercaptan and t-dodecyl mercaptan are mentioned. In the production of the synthetic rubber latex having (A) an unsaturated diene in the examples of the present invention, t-dodecyl mercaptan was used. The amount of such a chain transfer agent used is usually 0.01 to 5 parts by weight, preferably 0.1 to 3 parts by weight, based on 100 parts by weight of all the monomers used in the latex polymerization.

[0043] In addition to the above, additives such as antioxidants such as hindered phenols, antifoaming agents such as silicone-based, higher alcohol-based, and mineral oil-based, reaction terminators, and antifreezing agents may be used in the latex of the present invention as necessary.

[0044] <<Vinylpyridine-styrene-butadiene copolymer rubber latex>> The vinylpyridine-styrene-butadiene copolymer rubber latex is obtained by terpolymerizing a vinylpyridine-based monomer, a styrene-based monomer, and a conjugated diene-based butadiene monomer.

[0045] Here, the vinylpyridine-based monomer includes vinylpyridine and substituted vinylpyridine in which a hydrogen atom in the vinylpyridine is substituted with a substituent. Examples of the vinylpyridine-based compound include 2-vinylpyridine, 3-vinylpyridine, 4-vinylpyridine, 2-methyl-5-vinylpyridine, 5-ethyl-2-vinylpyridine, etc. Among these, 2-vinylpyridine is preferable. These vinylpyridine-based monomers may be used alone or in combination of two or more.

[0046] The styrene-based monomer includes styrene and substituted styrene in which a hydrogen atom in the styrene is substituted with a substituent. Examples of the styrene-based monomer include styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2,4-diisopropylstyrene, 2,4-dimethylstyrene, 4-t-butylstyrene, hydroxymethylstyrene, etc. Among these, styrene is preferable. These styrene-based monomers may be used alone or in combination of two or more.

[0047] Examples of the conjugated diene-based butadiene monomer include aliphatic conjugated butadiene compounds such as 1,3-butadiene and 2-methyl-1,3-butadiene. Among these, 1,3-butadiene is preferred. These conjugated diene-based butadiene monomers may be used alone or in combination of two or more.

[0048] For the synthesis of the vinylpyridine-styrene-butadiene copolymer rubber latex, known methods can be used. Specifically, the method described in "Japanese Patent Laid-Open No. 9-78045" based on the studies of the inventors of the present application can be used. And by using these methods, various compositions and internal particle structures can be obtained, such as copolymers with a uniform or different composition ratio within the same particles of the vinylpyridine-styrene-butadiene copolymer rubber latex.

[0049] Examples of commercially available products of copolymers with a uniform monomer mixing ratio within the same particles of the vinylpyridine-styrene-butadiene copolymer rubber latex include Nipol 2518 manufactured by Nippon Zeon Co., Ltd. and Pyratex manufactured by Nippon A&R Co., Ltd. Examples of commercially available products of copolymers with a different monomer mixing ratio within the same particles include the product V0658 manufactured by JSR Corporation. All of these can be used as the (A) synthetic rubber latex having an unsaturated diene of the adhesive composition for organic fiber cords of the present invention.

[0050] In the vinylpyridine-styrene-butadiene copolymer rubber latex of the present invention, the monomer ratio of vinylpyridine:styrene:butadiene is not particularly limited. However, it is preferable that the copolymer constituting the vinylpyridine-styrene-butadiene copolymer particles contains a copolymer obtained by polymerizing a monomer mixture consisting of 5 to 20% by mass of vinylpyridine, 10 to 40% by mass of styrene, and 45 to 75% by mass of butadiene. If the vinylpyridine is 5% by mass or more, an appropriate amount of pyridine sites having a vulcanization acceleration effect is present in the rubber component, and as the crosslinking degree by sulfur increases, the adhesive strength of the entire adhesive layer is further improved. If it is 20% by mass or less, the crosslinking degree of the rubber does not become over-vulcanized, and a hard adhesive can be obtained. Also, if the styrene is 10% by mass or more, the strength of the latex particles and the adhesive layer is sufficient, and the adhesive strength is further improved. If it is 40% by mass or less, it leads to ensuring the adhesive strength while making the co-vulcanization property of the adhesive layer and the adherend rubber appropriate. Furthermore, if the butadiene is 45% by mass or more, it becomes possible to form a more sufficient crosslinking. If it is 75% by mass or less, the crosslinking is made appropriate, and the durability due to volume and modulus changes can be ensured well. In the synthetic rubber latex (A) having an unsaturated diene in the examples of the present invention, the composition ratio of the monomer mixture of vinylpyridine:styrene:butadiene was 15:15:70.

[0051] The vinylpyridine-styrene-butadiene rubber latex can be a modified vinylpyridine-styrene-butadiene copolymer obtained by copolymerizing other copolymerizable monomers. These copolymerizable monomers can be those known in the art. For example, ethylene; α-olefin monomers such as propylene, 1-butene, 4-methyl-1-pentene, 1-hexene; aromatic vinyl monomers such as α-methylstyrene, monochlorostyrene; vinyl cyanide monomers such as acrylonitrile, methacrylonitrile; ethylenically unsaturated carboxylic acid monomers such as acrylic acid, methacrylic acid, cinnamic acid, crotonic acid, itaconic acid, fumaric acid, maleic acid, citraconic acid; ethylenically unsaturated carboxylic acid alkyl ester monomers such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate; unsaturated monomers containing a hydroxyalkyl group such as β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate; ethylenically unsaturated carboxylic acid amide monomers such as acrylamide, methacrylamide; anionic reactive emulsifiers such as ammonium polyoxyethylene alkyl propenyl ether sulfate, ammonium polyoxyethylene-1-(allyloxymethyl)alkyl ether sulfate, sodium propenyl-2-ethylhexyl sulfosuccinate, (meth)acrylic acid polyoxyethylene sulfate, (meth)acrylic acid polyoxyethylene phosphate; or a modified vinylpyridine-styrene-butadiene copolymer polymerized by including a nonionic reactive emulsifier such as polyoxyethylene alkyl propenyl phenyl ether can be used. In addition, these other copolymerizable monomers may be used alone or in combination of two or more kinds, as long as the amount is 20% by mass or less.

[0052] <(B) Gelatin> "(B) Gelatin" in the adhesive composition for organic fiber cords of the present invention is a water-soluble protein in which collagen molecules contained in connective tissues such as animal skin, bone, scale, tendon, etc. are treated with acid or alkali, heated with water to decompose, extracted and purified, and collagen is denatured, and refers to a linear polymer of amino acids.

[0053] In one embodiment of the present invention, an example of the principle of the action exhibited by “(B) gelatin” contained in the adhesive composition for organic fiber cords of the present invention will be described with reference to FIGS. 2 and 3. Conventionally, in an adhesive composition for organic fiber cords containing resorcin and formalin, the resorcin and formalin add a methylol group of a resole-type resorcin-formaldehyde condensate to a rosin acid salt used as an emulsifier on the surface of the rubber latex in the adhesive composition for organic fiber cords and co-condense, and the adhesiveness of the rubber latex is suppressed by the coating formed by the chemical cross-linking of the phenolic resin thus formed. On the other hand, in the adhesive composition for organic fiber cords of the present invention, gelatin 12 forms a network in water between gelatin molecules and coats the surface of a synthetic rubber latex 11 (core) having an unsaturated diene. By this coating, the adhesiveness of the synthetic rubber latex 11 having an unsaturated diene is suppressed (latex-gelatin protective film effect 20). As a result, the adhesive composition for organic fiber cords of the present invention containing “(B) gelatin” (2) By suppressing the adhesiveness of the rubber latex measured as the mechanical stability under shear strain of the adhesive liquid, in the step of coating the organic fiber cord with the adhesive composition for organic fiber cords and drying and thermosetting it, it becomes possible to suppress the adhesion of the adhesive composition for organic fiber cords to a roll or the like, and the workability is good, and it becomes such a thing. Furthermore, the gelatin 12 of the adhesive composition for organic fiber cords 2 of the present invention coated on the surface of the organic fiber cord 1 chemically cross-links with the acid component on the surface of the rubber latex 11 by heat treatment, (3) The adhesiveness between the organic fiber cord and the coated rubber composition is good, and it becomes such a thing.

[0054] Furthermore, in the adhesive composition for organic fiber cords of the present invention, the gelatin 12 forms a gelatin-isocyanate crosslink 22 between the functional groups of the gelatin 12 and the activated isocyanate groups 14 of the aqueous urethane compound 13 having (thermally dissociable blocked) isocyanate groups. As a result, the adhesive composition for organic fiber cords of the present invention containing "(B) gelatin" and "(C) an aqueous compound having (thermally dissociable blocked) isocyanate groups" is (3) such that the adhesiveness between the organic fiber cord and the coating rubber composition is good, becomes so.

[0055] (B) Gelatin is not limited, but can be obtained by extracting collagen, which is a component derived from living tissues such as the skin, bones, and tendons of animals (for example, pigs, cows, rabbits, sheep, mice, birds, fish, and humans) by applying heat. Note that the collagen can also be obtained as a commercial product. Also, cases where the collagen extracted from living tissues is produced by genetic recombination technology or the like can be exemplified. In addition, it can also be obtained by acid-treating the skin of animals (acid-treated gelatin) or by alkali-treating the bones of animals (alkali-treated gelatin). These gelatins are composed of polypeptide chains with a number-average molecular weight of about 100,000 and their dimers, trimers, and polypeptide chains obtained by hydrolyzing them, and the number-average molecular weight is about 300,000.

[0056] In the adhesive composition for organic fiber cords of the present invention, the (B) gelatin is not particularly limited as long as it is gelatin that has the ability to form a gel by solidifying into a jelly-like state through sol-gel transition when the temperature is lowered by heating an aqueous gelatin solution and then cooling it. Gelatin obtained as described above, and gelatin obtained as described above further subjected to thermal decomposition, acid decomposition, alkali decomposition, or proteolytic enzyme decomposition to obtain a gelatin processed product such as a low molecular weight gelatin having a polypeptide chain with a number average molecular weight of 2,000 to 26,000, and furthermore, commercially available gelatin can be used as the (B) gelatin in the adhesive composition for organic fiber cords of the present invention. These may be used alone or in combination of two or more.

[0057] Also, in the adhesive composition for organic fiber cords of the present invention, the content of (B) gelatin is not particularly limited, but it is preferably 0.1% by mass or more and preferably 15% by mass or less. If it is 0.1% by mass or more, it becomes possible to further suppress the adhesion of the adhesive composition for organic fiber cords to rolls and the like, and there is an advantage that workability becomes better. If it is 15% by mass or less, the amount of gelatin contained in the adhesive layer does not become too large, and sufficient fracture resistance of the adhesive layer can be ensured. More preferably, it is 0.4% by mass or more and 5% by mass or less.

[0058] <(C) Aqueous compound having a (thermally dissociable blocked) isocyanate group> In the "adhesive composition for organic fiber cords of the present invention", the "(thermally dissociable blocked) isocyanate group" in the "(C) aqueous compound having a (thermally dissociable blocked) isocyanate group" means a thermally dissociable blocked isocyanate group or an isocyanate group, (i) A thermally dissociable blocked isocyanate group formed by the reaction of an isocyanate group with a thermally dissociable blocking agent for the isocyanate group, (ii) An isocyanate group that is unreacted with a thermally dissociable blocking agent for the isocyanate group, (C) Isocyanate groups generated by dissociation of the thermal dissociation blocking agent from the thermally dissociable blocked isocyanate groups, (D) Isocyanate groups, are included.

[0059] In the adhesive composition for organic fiber cords of the present invention, the "aqueous" in the "(C) (thermally dissociable blocked) isocyanate group-containing aqueous compound" indicates water solubility or water dispersibility. The water solubility does not necessarily mean complete water solubility, but also means partial water solubility or no phase separation in the aqueous solution of the adhesive composition for organic fiber cords of the present invention.

[0060] Also, in the adhesive composition for organic fiber cords of the present invention, the content of the aqueous compound having the (C) (thermally dissociable blocked) isocyanate group is not particularly limited, but is preferably 5% by mass or more and preferably 75% by mass or less. If it is 5% by mass or more, the adhesiveness between the organic fiber cord and the coating rubber composition becomes better. Also, if it is 75% by mass or less, it becomes possible to ensure a certain amount or more of other components such as rubber latex blended in the adhesive composition for organic fiber cords. As a result, the adhesiveness to the adherend rubber becomes better. More preferably, it is 15% by mass or more and 60% by mass or less.

[0061] The "(C) (thermally dissociable blocked) isocyanate group-containing aqueous compound" in the adhesive composition for organic fiber cords of the present invention is (C-1) A water-dispersible (thermally dissociable blocked) isocyanate compound, which is an addition product of a polyisocyanate having an aromatic ring and a blocking agent having one or more active hydrogen groups, is preferably.

[0062] Also, the "(C) (thermally dissociable blocked) isocyanate group-containing aqueous compound" in the adhesive composition for organic fiber cords of the present invention is (C-2) An aqueous urethane compound having a (thermally dissociable blocked) isocyanate group, is more preferable.

[0063] <<(Water-dispersible (thermally dissociable blocked) isocyanate compound which is an addition product of a polyisocyanate having a (C-1) aromatic ring and a blocking agent having one or more active hydrogen groups)>> Regarding the “(Water-dispersible (thermally dissociable blocked) isocyanate compound which is an addition product of a polyisocyanate having a (C-1) aromatic ring and a blocking agent having one or more active hydrogen groups)”, the “active hydrogen group” refers to a group containing hydrogen that becomes active hydrogen (atomic hydrogen (hydrogen radical) and hydride ion (hydride)) when placed under suitable conditions. Examples of the active hydrogen group include an amino group and a hydroxyl group.

[0064] Regarding the “(Water-dispersible (thermally dissociable blocked) isocyanate compound which is an addition product of a polyisocyanate having a (C-1) aromatic ring and a blocking agent having one or more active hydrogen groups)”, the “blocking agent” is not particularly limited as long as it is a blocking agent compound that can protect the isocyanate group from any chemical reaction and, if necessary, dissociate the blocking agent by heat treatment to restore the isocyanate group. Preferably, the blocking agent is a blocking agent compound that can dissociate by heat treatment at the temperature of the step in the hot zone 7 of FIG. 1 to restore the isocyanate group.

[0065] The "blocking agent having one or more active hydrogen groups" related to the "aqueous dispersible (thermally dissociable blocked) isocyanate compound, which is an addition product of a polyisocyanate having an aromatic ring (C-1) and a blocking agent having one or more active hydrogen groups" includes alcohols, phenols, active methylene compounds, oximes, lactams, amines, etc., and is not particularly limited. Specifically, lactams such as ε-caprolactam, δ-valerolactam, and γ-butyrolactam; phenols such as phenol, cresol, ethylphenol, butylphenol, octylphenol, nonylphenol, dinonylphenol, thiophenol, chlorophenol, and amylphenol; oximes such as methyl ethyl ketoxime, acetoxime, acetophenone oxime, benzophenone oxime, and cyclohexanone oxime; alcohols such as methanol, ethanol, butanol, isopropyl alcohol, butyl alcohol, and cyclohexanol; dialkyl malonates such as dimethyl malonate and diethyl malonate; active methylene compounds such as methyl acetoacetate, ethyl acetoacetate, and acetylacetone; mercaptans such as butyl mercaptan and dodecyl mercaptan; amides such as acetanilide and acetic acid amide; imides such as succinimide, phthalimide, and maleimide; sulfites such as sodium bisulfite; cellosolves such as methyl cellosolve, ethyl cellosolve, and butyl cellosolve; pyrazoles such as pyrazole, 3,5-dimethylpyrazole, 3-methylpyrazole, 4-benzyl-3,5-dimethylpyrazole, 4-nitro-3,5-dimethylpyrazole, 4-bromo-3,5-dimethylpyrazole, and 3-methyl-5-phenylpyrazole; amines such as dimethylamine, diethylamine, di-n-propylamine, diisopropylamine, dicyclohexylamine, diphenylamine, xylidine, N,N-diethylhydroxyamine, N,N'-diphenylformamidine, 2-hydroxypyridine, 3-hydroxypyridine, and 2-mercaptopyridine; and triazoles such as 1,2,4-triazole, etc. Mixtures of two or more of these may also be used. These blocking agents can preferably use phenol, ε-caprolactam, and ketoxime, which can easily and stably obtain the thermosetting of the adhesive composition by thermal dissociation upon heating.

[0066] As the "water-dispersible (thermally dissociable blocked) isocyanate compound, which is an addition product of a polyisocyanate having an aromatic ring and a blocking agent having one or more active hydrogen groups", specifically, for example, aromatic polyisocyanate compounds and aromatic aliphatic polyisocyanate compounds can be mentioned. Examples of the aromatic polyisocyanate compounds include phenylenediisocyanates such as m-phenylenediisocyanate and p-phenylenediisocyanate; tolylenediisocyanates such as 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate (TDI); diphenylmethane diisocyanates such as 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), dialkyldiphenylmethane diisocyanate, and tetraalkyldiphenylmethane diisocyanate; polymethylene polyphenyl polyisocyanate (polymeric MDI); m- or p-isocyanatophenylsulfonyl isocyanates; diisocyanatobiphenyls such as 4,4'-diisocyanatobiphenyl and 3,3'-dimethyl-4,4'-diisocyanatobiphenyl; naphthalene diisocyanates such as 1,5-naphthalene diisocyanate; and the like. Examples of the aromatic aliphatic polyisocyanate compounds include xylylene diisocyanates such as m-xylylene diisocyanate, p-xylylene diisocyanate (XDI), and tetramethylxylylene diisocyanate; diethylbenzene diisocyanate; and α,α,α,α-tetramethylxylylene diisocyanate (TMXDI); and the like. Furthermore, modified products such as carbodiimide, polyol, and allophanate of the aromatic polyisocyanate compound are also included. Among these, from the viewpoint of the code converging property of the adhesive composition, an aromatic polyisocyanate compound is preferable, and 2,6-tolylene diisocyanate (TDI), 4,4'-diphenylmethane diisocyanate (MDI) or polymethylene polyphenyl polyisocyanate (polymeric MDI) is more preferable, and 4,4'-diphenylmethane diisocyanate (MDI) is particularly preferable.

[0067] <<(C-2) Aqueous urethane compound having a thermally dissociable blocked isocyanate group>> Regarding the "(C-2) aqueous urethane compound having a thermally dissociable blocked isocyanate group", the thermally dissociable blocking agent is not particularly limited as long as it is a blocking agent compound that can protect the isocyanate group from any chemical reaction and dissociate the blocking agent by heat treatment as necessary to restore the isocyanate group. As specific examples of the thermal dissociation blocking agent, the same compounds as the blocking agents described above in the section of <<(C-1) A water-dispersible (thermally dissociable blocked) isocyanate compound which is an addition product of a polyisocyanate having an aromatic ring and a blocking agent having one or more active hydrogen groups>> can be used. Preferably, phenols such as phenol, thiophenol, chlorophenol, cresol, resorcinol, p-sec-butylphenol, p-tert-butylphenol, p-sec-amylphenol, p-octylphenol, p-nonylphenol, etc.; secondary or tertiary alcohols such as isopropyl alcohol, tert-butyl alcohol, etc.; aromatic secondary amines such as diphenylamine, xylylidene, etc.; phthalimides; lactams such as δ-valerolactam, etc.; caprolactams such as ε-caprolactam, etc.; dialkyl malonates such as diethyl malonate, dimethyl malonate, etc., active methylene compounds such as acetylacetone, alkyl acetoacetate, etc.; oximes such as acetoxime, methyl ethyl ketoxime, cyclohexanone oxime, etc.; basic nitrogen compounds such as 3-hydroxypyridine, 1,2-pyrazole, 3,5-dimethylpyrazole, 1,2,4-triazole, diisopropylamine, N,N'-diphenylformamidine, etc. and sodium bisulfite, etc. are mentioned. As these blocking agents, phenol, ε-caprolactam and ketooxime, which can easily and stably obtain the thermosetting of the adhesive composition by thermal dissociation upon heating, can be preferably used.

[0068] The "aqueous" in the "aqueous urethane compound" means water-soluble or water-dispersible. The water-soluble does not necessarily mean complete water-solubility, but also means partially water-soluble or not phase-separating in the aqueous solution of the adhesive composition for organic fiber cords of the present invention.

[0069] The "urethane compound" in the "aqueous urethane compound" is a compound having a covalent bond formed between the nitrogen of an amine and the carbon of a carbonyl group, and refers to a compound represented by the following general formula.

Chemical formula

[0070] The molecular weight of the "aqueous urethane compound having a (C-2) (thermally dissociable blocked) isocyanate group" is not particularly limited as long as the aqueous property is maintained, but preferably the number average molecular weight is 1,500 to 100,000, and particularly preferably the number average molecular weight is 9,000 or less.

[0071] The method for synthesizing the "aqueous urethane compound having a (C-2) (thermally dissociable blocked) isocyanate group" in the adhesive composition for organic fiber cords of the present invention is not particularly limited as described above, but known methods such as the method described in JP-A-63-51474 can be used.

[0072] <<Preferred Embodiment of "Aqueous Urethane Compound Having a (C-2) (Thermally Dissociable Blocked) Isocyanate Group">> Preferred embodiments of the "aqueous urethane compound having a (C-2) (thermally dissociable blocked) isocyanate group" in the adhesive composition for organic fiber cords of the present invention are (α) an organic polyisocyanate compound having 3 or more and 5 or less functional groups and a number average molecular weight of 2,000 or less, (β) a compound having 2 or more and 4 or less active hydrogen groups and a number average molecular weight of 5,000 or less, (γ) a thermally dissociable blocking agent, and (δ) a compound having at least one active hydrogen group and at least one hydrophilic group selected from anionic, cationic, or nonionic groups, wherein the mixing ratios of (α), (β), (γ), and (δ) with respect to the total amount of (α), (β), (γ), and (δ) are for (α), 40% by mass or more and 85% by mass or less, for (β), 5% by mass or more and 35% by mass or less, for (γ), 5% by mass or more and 35% by mass or less, and for (δ), 5% by mass or more and 35% by mass or less. It is a reaction product after mixing and reacting so as to obtain and when the molecular weight of the isocyanate group (-NCO) is 42, the constituent ratio of the (thermally dissociable blocked) isocyanate group in the reaction product is 0.5% by mass or more and 11% by mass or less. It is characterized by this. This above-mentioned "aqueous urethane compound having a (C-2) (thermally dissociable blocked) isocyanate group" has the advantage of increasing the self-water solubility of the urethane compound because it has both a site composed of a (thermally dissociable blocked) isocyanate group and a hydrophilic site having a hydrophilic group.

[0073] The organic polyisocyanate compound having 3 or more and 5 or less functional groups and a number average molecular weight of 2,000 or less is not particularly limited, but is preferably an aromatic polyisocyanate compound and its oligomer, and other aliphatic, alicyclic, heterocyclic polyisocyanate compounds and their oligomers may also be used. The "aqueous urethane compound having a (C-2) (thermally dissociable blocked) isocyanate group", which is a reaction product after reacting such an organic polyisocyanate compound having 3 or more and 5 or less functional groups and a number average molecular weight of 2,000 or less, is more likely to be dispersed into the gaps between the polymer chains of the organic fiber cord. As specific examples, aliphatic polyisocyanate compounds include ethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,12-dodecane diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, dimer acid diisocyanate, lysine diisocyanate, etc.; alicyclic polyisocyanate compounds include cyclobutane-1,3-diisocyanate, cyclohexane-1,3-diisocyanate, cyclohexane-1,4-diisocyanate, isophorone diisocyanate, 4,4'-methylenebis(cyclohexyl isocyanate), methylcyclohexane-2,4-diisocyanate, methylcyclohexane-2,6-diisocyanate, 1,3-(isocyanatomethyl)cyclohexane, etc.; heterocyclic polyisocyanate compounds include tolylene diisocyanate adduct of 1,3,5-tris(2'-hydroxyethyl)isocyanuric acid, etc.; aromatic polyisocyanate compounds include m-phenylene diisocyanate, p-phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, m-xylylene diisocyanate, p-xylylene diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, m-tetramethylxylylene diisocyanate, p-tetramethylxylylene diisocyanate, methine tris(4-phenyl isocyanate), tris(4-isocyanatophenyl)methane, thiophosphoric acid tris(4-isocyanatophenyl ester), 3-isopropenyl-α',α'-dimethylbenzyl isocyanate and oligomer mixtures thereof, or modified products such as carbodiimide, polyol and allophanate of these polyisocyanate compounds, etc. Among these, aromatic polyisocyanate compounds are preferred, and particularly preferred are methylene diphenyl polyisocyanate, polyphenylene polymethylene polyisocyanate, and the like. Polyphenylene polymethylene polyisocyanate having a number average molecular weight of 2,000 or less is preferred, and polyphenylene polymethylene polyisocyanate having a number average molecular weight of 1,000 or less is particularly preferred. This is because the "aqueous urethane compound having a (C-2) (thermally dissociable blocked) isocyanate group", which is a reaction product after reacting an organic polyisocyanate compound having such (α) 3 or more and 5 or less functional groups and having a number average molecular weight of 2,000 or less, is more likely to be dispersed into the gaps between the polymer chains of the organic fiber cord.

[0074] The compound having (β) 2 or more and 4 or less active hydrogen groups and having a number average molecular weight of 5,000 or less is not particularly limited, but specifically, compounds selected from the group consisting of the following (i) to (vii) and the like can be mentioned: (i) Polyhydric alcohols having 2 or more and 4 or less hydroxyl groups and having a number average molecular weight of 5,000 or less, (ii) Polyvalent amines having 2 or more and 4 or less primary and / or secondary amino groups and having a number average molecular weight of 5,000 or less, (iii) Amino alcohols having 2 or more and 4 or less primary and / or secondary amino groups and hydroxyl groups and having a number average molecular weight of 5,000 or less, (iv) Polyester polyols having 2 or more and 4 or less hydroxyl groups and having a number average molecular weight of 5,000 or less, (v) Polybutadiene polyols having 2 or more and 4 or less hydroxyl groups and having a number average molecular weight of 5,000 or less and copolymers thereof with other vinyl monomers (vi) Polychloroprene polyols having 2 or more and 4 or less hydroxyl groups and having a number average molecular weight of 5,000 or less and copolymers thereof with other vinyl monomers (vii) Polyether polyols having 2 or more and 4 or less hydroxyl groups and having a number average molecular weight of 5,000 or less, Polyvalent amine, C2-C4 alkylene oxide polyadducts of polyhydric phenols and amino alcohols, C2-C4 alkylene oxide polyadducts of polyhydric alcohols having 3 or more carbon atoms, C2-C4 alkylene oxide copolymers, or C3-C4 alkylene oxide polymers.

[0075] Here, regarding the "aqueous urethane compound having a (C-2) (thermally dissociable blocked) isocyanate group" in the adhesive composition for organic fiber cords of the present invention, the "active hydrogen group" refers to a group containing hydrogen that becomes active hydrogen (atomic hydrogen (hydrogen radical) and hydride ion (hydride)) when placed under suitable conditions. Examples of the active hydrogen group include an amino group and a hydroxyl group.

[0076] As the compound having at least one active hydrogen group and at least one hydrophilic group that is anionic, cationic, or nonionic among the "(δ) compounds having at least one active hydrogen group and at least one hydrophilic group", the compound having at least one active hydrogen group and at least one anionic hydrophilic group is not particularly limited, but examples include aminosulfonic acids such as taurine, N-methyltaurine, N-butyltaurine, and sulfanilic acid, and aminocarboxylic acids such as glycine and alanine.

[0077] The method for synthesizing the "aqueous urethane compound having a (C-2) (thermally dissociable blocked) isocyanate group" in the adhesive composition for organic fiber cords of the present invention by mixing and reacting the above (α), (β), (γ), and (δ) is not particularly limited, but known methods such as the method described in JP-A-63-51474 can be used.

[0078] <<Another preferred embodiment of the "aqueous urethane compound having a (C-2) (thermally dissociable blocked) isocyanate group">> Another preferred embodiment of the "aqueous urethane compound having a (C-2) (thermally dissociable blocked) isocyanate group" in the adhesive composition for organic fiber cords of the present invention is (α) An organic polyisocyanate compound having 3 or more and 5 or less functional groups and a number average molecular weight of 2,000 or less, (β) A compound having 2 or more and 4 or less active hydrogen groups and a number average molecular weight of 5,000 or less, (γ) A thermal dissociable blocking agent, and (δ) A compound having at least one active hydrogen group and at least one hydrophilic group which is anionic, cationic, or nonionic, (ε) A compound other than (α), (β), (γ), and (δ) that contains an active hydrogen group are mixed so that the respective mixing ratios with respect to the total amount of (α), (β), (γ), (δ), and (ε) are for (α), 40% by mass or more and less than 85% by mass, for (β), 5% by mass or more and 35% by mass or less, for (γ), 5% by mass or more and 35% by mass or less, for (δ), 5% by mass or more and 35% by mass or less, for (ε), more than 0% by mass and 45% by mass or less and are reacted to obtain a reaction product, and moreover, when the molecular weight of the isocyanate group (-NCO) is 42, the constituent ratio of the (thermally dissociable blocked) isocyanate group in the reaction product is 0.5% by mass or more and 11% by mass or less. It is characterized by this. This aqueous urethane compound having the above (C-2) (thermally dissociable blocked) isocyanate group has the advantage that the self-water solubility of the urethane compound is increased because it has both a site composed of the (thermally dissociable blocked) isocyanate group and a hydrophilic site having a hydrophilic group.

[0079] Here, an organic polyisocyanate compound having (α) 3 or more and 5 or less functional groups and a number average molecular weight of 2,000 or less, a compound having (β) 2 or more and 4 or less active hydrogen groups and a number average molecular weight of 5,000 or less, (γ) a thermal dissociable blocking agent, and (δ) a compound having at least one active hydrogen group and at least one hydrophilic group of anionic, cationic, or nonionic nature are, except for the mixing ratio, as described in the aforementioned <<Preferred Embodiment of "(C-2) (Thermal Dissociable Blocked) Isocyanate Group-Containing Aqueous Urethane Compound">>.

[0080] By mixing and reacting the above (α), (β), (γ), (δ), and (ε), the method for synthesizing the "(C-2) (Thermal Dissociable Blocked) Isocyanate Group-Containing Aqueous Urethane Compound" in the adhesive composition for organic fiber cords of the present invention is not particularly limited, but a known method such as the method described in JP-A-63-51474 can be used.

[0081] <<Another Preferred Embodiment of "(C-2) (Thermal Dissociable Blocked) Isocyanate Group-Containing Aqueous Urethane Compound">> Another preferred embodiment of the "(C-2) (Thermal Dissociable Blocked) Isocyanate Group-Containing Aqueous Urethane Compound" in the adhesive composition for organic fiber cords of the present invention is represented by the following general formula (I) [Chemical Formula] (In formula (I), A is the residue obtained by eliminating the active hydrogen group from the organic polyisocyanate compound, X is the residue obtained by eliminating the active hydrogen group from a polyol compound having 2 or more and 4 or less hydroxyl groups and a number average molecular weight of 5,000 or less, Y is the residue obtained by eliminating the active hydrogen group from the thermal dissociable blocking agent, Z is the residue obtained by eliminating the active hydrogen group from a compound having at least one active hydrogen group and at least one group capable of forming a salt or a hydrophilic polyether chain, n is an integer of 2 or more and 4 or less, p + m is an integer of 2 or more and 4 or less (m ≧ 0.25), representing), and is characterized by being represented by The above-mentioned "(C-2) (thermally dissociable blocked) isocyanate group-containing aqueous urethane compound" has a site composed of a (thermally dissociable blocked) isocyanate group and a hydrophilic site having a hydrophilic group, so that the self-water solubility of the urethane compound is increased.

[0082] Here, the "organic polyisocyanate compound" which is the residue obtained by eliminating the active hydrogen group of the "organic polyisocyanate compound" represented by A in formula (I) preferably contains an aromatic ring. This is because the "(C-2) (thermally dissociable blocked) isocyanate group-containing aqueous urethane compound" is more likely to be dispersed into the gaps between the polymer chains of the organic fiber cord. Although not particularly limited, for example, methylene diphenyl polyisocyanate, polyphenylene polymethylene polyisocyanate, etc. can be mentioned. Polyphenylene polymethylene polyisocyanate having a number average molecular weight of 6,000 or less is preferable, and polyphenylene polymethylene polyisocyanate having a number average molecular weight of 4,000 or less is particularly preferable.

[0083] X in formula (I), which is the residue obtained by eliminating the active hydrogen group of the "polyol compound having 2 or more and 4 or less hydroxyl groups and a number average molecular weight of 5,000 or less", the "polyol compound having 2 or more and 4 or less hydroxyl groups and a number average molecular weight of 5,000 or less" is not particularly limited, but specifically, compounds selected from the group consisting of the following (i) to (vi) can be mentioned: (i) Polyhydric alcohols having 2 or more and 4 or less hydroxyl groups and a number average molecular weight of 5,000 or less, (ii) Amino alcohols having 2 or more and 4 or less primary and / or secondary amino groups and hydroxyl groups and a number average molecular weight of 5,000 or less, (iii) Polyester polyols having 2 or more and 4 or less hydroxyl groups and a number average molecular weight of 5,000 or less, (iv) Polybutadiene polyols having 2 to 4 hydroxyl groups and a number average molecular weight of 5,000 or less, and copolymers thereof with other vinyl monomers, (v) Polychloroprene polyols having 2 to 4 hydroxyl groups and a number average molecular weight of 5,000 or less, and copolymers thereof with other vinyl monomers, (vi) Polyether polyols having 2 to 4 hydroxyl groups and a number average molecular weight of 5,000 or less, Polyvalent amines, C2 - C4 alkylene oxide polyadducts of polyvalent phenols and amino alcohols, C2 - C4 alkylene oxide polyadducts of polyhydric alcohols having 3 or more carbon atoms, C2 - C4 alkylene oxide copolymers, or C3 - C4 alkylene oxide polymers.

[0084] The "(C - 2) (thermally dissociable blocked) isocyanate group - containing aqueous urethane compound" in the adhesive composition for organic fiber cords of the present invention is not particularly limited, but commercially available products such as Elastron BN27, BN77, BN11, etc. manufactured by Dai - Ichi Kogyo Seiyaku Co., Ltd. can also be used. Preferably, it is the product synthesized in the following examples in this specification, or the above - mentioned BN77.

[0085] <<Adhesion - promoting effect by an aqueous compound having a (C) (thermally dissociable blocked) isocyanate group>> In a conventional adhesive composition for organic fiber cords containing resorcin and formalin, a sea - island structure in which rubber latex particles (analogous to islands) are dispersed in a phenolic resin (analogous to the sea) formed by the co - condensation of the resorcin and formalin is formed. Thereby, good adhesiveness between the phenolic resin coating the surface of the organic fiber cord and the organic fiber cord has been obtained.

[0086] On the other hand, in the adhesive composition for organic fiber cords of the present invention, instead of the phenolic resin obtained by the co - condensation of resorcin and formalin, an aqueous compound having a "(C) (thermally dissociable blocked) isocyanate group" may act as an adhesion promoter due to the following two functional effects: (a) A functional effect of promoting the adhesion between the organic fiber cord and the adhesive layer by distributing the aqueous compound near the interface between the organic fiber cord and the adhesive layer formed by the adhesive composition for organic fiber cords, (b) A functional effect of reinforcing the adhesive layer by forming a three - dimensional network structure through cross - linking by isocyanate groups of the compound having a (thermally dissociable blocked) isocyanate group within the adhesive layer formed by the adhesive composition for organic fiber cords. As a result, in the adhesive composition for organic fiber cords of the present invention, the "aqueous compound having a (C) (thermally dissociable blocked) isocyanate group" (3) Contributes mainly to the characteristic of the adhesive composition for organic fiber cords of the present invention that the adhesiveness between the organic fiber cord and the coating rubber composition is good. In an embodiment of the adhesive composition for organic fiber cords of the present invention, an example of the principles of the two functional effects as adhesion promoters (a) and (b) of the "aqueous urethane compound having a (C) (thermally dissociable blocked) isocyanate group" is as follows. When the "aqueous urethane compound having a (C) (thermally dissociable blocked) isocyanate group" is preferably

[0087] (C - 1) A water - dispersible (thermally dissociable blocked) isocyanate compound which is an addition product of a polyisocyanate having an aromatic ring and a blocking agent having one or more active hydrogen groups, in this case, referring also to FIG. 2, (C - 2) An aqueous urethane compound having a (thermally dissociable blocked) isocyanate group, in this case, referring also to FIG. 3, The following will be described in detail.

[0088] <<<Regarding the functional effect as the adhesion promoter of (a)>>> ​Synthetic resin materials such as polyester, such as polyethylene terephthalate, which are widely used as organic fiber cords, are composed of flat linear polymer chains. And the surface of the polymer chain or the gap between the polymer chains has a π-electron atmosphere derived from aromatics or the like contained in the polymer chain. Furthermore, polyester has particularly few hydroxyl groups on the surface compared to 6,6-nylon. Therefore, conventionally, an adhesive composition for organic fiber cords used for organic fiber cords made of polyester contains, for the purpose of obtaining sufficient adhesive strength, * the dispersion of the adhesive composition for organic fiber cords into the gaps between the polymer chains of the organic fiber cords, and * the adhesion of the adhesive layer formed by the adhesive composition for organic fiber cords to the surface of the polymer chains of the organic fiber cords, molecules having a planar structure with an aromatic ring having aromatic π electrons on the side (a "portion that easily diffuses into the organic fiber cord") as an adhesion promoter. As a specific example of such an adhesion promoter, conventionally, "a water-dispersible (thermally dissociable blocked) isocyanate compound that is an addition product of a polyisocyanate having an aromatic ring and a blocking agent having one or more active hydrogen groups" has been used.

[0089] In the adhesive layer containing the "water-dispersible (thermally dissociable blocked) isocyanate compound that is an addition product of a polyisocyanate having an aromatic ring and a blocking agent having one or more active hydrogen groups", as shown in FIG. 2, inside the adhesive layer 32 formed by the adhesive composition 2 for organic fiber cords, the water-dispersible (thermally dissociable blocked) isocyanate compound 40 that is an addition product of a polyisocyanate having an aromatic ring and a blocking agent having one or more active hydrogen groups diffuses into the organic fiber cord 1 (aromatic isocyanate - organic fiber cord diffusion effect 41), and forms a gelatin - isocyanate crosslink 22 with the gelatin 12 contained in the adhesive layer, thereby * the dispersion of the adhesive composition 2 for organic fiber cords into the gaps between the polymer chains of the organic fiber cord 1, and * the adhesion of the adhesive layer 32 formed by the adhesive composition 2 for organic fiber cords to the surface of the polymer chains of the organic fiber cord 1, It becomes

[0090] In addition, the "aqueous dispersible (thermally dissociable blocked) isocyanate compound, which is an addition product of a polyisocyanate having an aromatic ring (C-1) and a blocking agent having one or more active hydrogen groups" preferably has a particle size of 0.01 to 0.50 μm. The "aqueous dispersible (thermally dissociable blocked) isocyanate compound, which is an addition product of a polyisocyanate having an aromatic ring (C-1) and a blocking agent having one or more active hydrogen groups" has a property that in the adhesive layer, with the passage of time, it easily diffuses from the surface of the polymer chain of the organic fiber cord to the gap between the polymer chains of the organic fiber cord where aromatic π electrons are more abundant. Along with this, the effect as an adhesion promoter decreases. However, if the particle size is 0.01 μm or more, it will remain more on the surface of the organic fiber cord. Also, if the particle size is 0.50 μm or less, the problem that the compound settles in the liquid and the dispersion in the adhesive layer becomes non-uniform is less likely to occur. Furthermore, the "aqueous dispersible (thermally dissociable blocked) isocyanate compound, which is an addition product of a polyisocyanate having an aromatic ring (C-1) and a blocking agent having one or more active hydrogen groups" is more preferably a (blocked) isocyanate such as methylene diphenyl diisocyanate having a particle size of 0.01 to 0.50 μm (see Patent Document 3).

[0091] The adhesive composition for organic fiber cords of the present invention is more preferably a "(C-2) aqueous urethane compound having a (thermally dissociable blocked) isocyanate group" which has a hydrophobic aromatic polyisocyanate part that is a part "easily diffusible into the organic fiber cord" and a hydrophilic molecular chain part that is a part "difficult to diffuse into the organic fiber cord" in its molecular structure.

[0092] In the adhesive composition for organic fiber cords of the present invention, as shown in FIG. 3, in the adhesive layer 32 formed by the adhesive composition 2 for organic fiber cords, the aqueous urethane compound 13 having a (thermally dissociable blocked) isocyanate group has both a portion 15 that easily diffuses into the organic fiber cord 1 and a portion 16 that hardly diffuses into the organic fiber cord 1. Among these, due to the presence of the portion 15 that easily diffuses into the organic fiber cord, * the adhesive composition 2 for organic fiber cords is dispersed into the gaps between the polymer chains of the organic fiber cord 1, and * the adhesive layer 32 formed by the adhesive composition 2 for organic fiber cords adheres closely to the surface of the polymer chains of the organic fiber cord 1, resulting in the above. Furthermore, due to the presence of the portion 16 that hardly diffuses into the organic fiber cord 1, the aqueous urethane compound 13 having a (thermally dissociable blocked) isocyanate group exhibits high adhesiveness between the organic fiber cord 1 and the adhesive layer 32 formed by the adhesive composition 2 for organic fiber cords (aqueous urethane - organic fiber cord interfacial effect 24). As a result of these, the adhesive composition for organic fiber cords of the present invention containing the "aqueous urethane compound having a (C-2) (thermally dissociable blocked) isocyanate group" is more (3) has good adhesiveness between the organic fiber cord and the coating rubber composition, becoming such.

[0093] Also, since the "(C) (thermally dissociable blocked) isocyanate group-containing aqueous compound" has a tendency to disperse in water from the surface of the hydrophobic organic fiber cord 1, it is more preferably the "(C-2) (thermally dissociable blocked) isocyanate group-containing aqueous urethane compound", which is an aromatic polyisocyanate compound having an anionic or nonionic water-soluble functional group.

[0094] <<<Regarding the functional effects as the adhesion promoter in (b)>>> In the adhesive layer where the "aqueous compound having a (C) (thermally dissociable blocked) isocyanate group" is a "water-dispersible (thermally dissociable blocked) isocyanate compound which is an addition product of a polyisocyanate having an aromatic ring and a blocking agent having one or more active hydrogen groups", as shown in Fig. 2, the activated isocyanate groups obtained by thermal dissociation of the blocking agent of the water-dispersible (thermally dissociable blocked) isocyanate compound 40, which is an addition product of a polyisocyanate having an aromatic ring and a blocking agent having one or more active hydrogen groups, form a gelatin-isocyanate crosslink 22 with the molecular chains of the adjacent gelatin 12, and an adhesive layer including a three-dimensional network structure is obtained. As a result, the adhesive composition for organic fiber cords of the present invention containing a "water-dispersible (thermally dissociable blocked) isocyanate compound which is an addition product of a polyisocyanate having an aromatic ring and a blocking agent having one or more active hydrogen groups" (3) has good adhesion between the organic fiber cord and the coating rubber composition, and becomes such a thing.

[0095] In addition, since a material in which a powder mainly composed of an aromatic is forcibly emulsified and dispersed is used, in order to prevent the compound from settling in the liquid and becoming unevenly dispersed or aggregated in the adhesive layer, it is preferable to stir the dipping bath (dipping tank) 3 in Fig. 1.

[0096] On the other hand, in the adhesive composition for organic fiber cords of the present invention, it is more preferable that the "(C) (thermally dissociable blocked) isocyanate group-containing aqueous urethane compound" is a "(C-2) (thermally dissociable blocked) isocyanate group-containing aqueous urethane compound". And the "(C-2) (thermally dissociable blocked) isocyanate group-containing aqueous urethane compound" preferably contains an alkylene oxide part or the like in the molecule of the compound. This is because it can be more easily and uniformly dispersed in water than the "water-dispersible (thermally dissociable blocked) isocyanate compound which is an addition product of a polyisocyanate having an aromatic ring and a blocking agent having one or more active hydrogen groups" by self-emulsification or the like due to swelling of water.

[0097] And since the aqueous urethane compound having a "(C-2) (thermolabile blocked) isocyanate group" uniformly dispersed in water contains a hydrophobic organic isocyanate moiety within the molecule of the compound, it forms stable associated micelles between the hydrophobic portions of adjacent water-soluble urethanes, similar to the water-soluble urethane used as an associative thickener, and comes to have a three-dimensional network structure due to the hydrophobic interaction between the aqueous urethanes uniformly dispersed in the liquid.

[0098] Next, after coating the organic fiber cord with the adhesive composition for organic fiber cords having the three-dimensional network structure formed by the hydrophobic bond, it is dried and thermoset. Then, as shown in FIG. 3, the activated isocyanate groups 14 from which the blocking agent has thermally dissociated form activated isocyanate crosslinks 23 by covalent bonds between adjacent ones, and an adhesive layer including the three-dimensional network structure of the aqueous urethane compound 13 having a (thermolabile blocked) isocyanate group is obtained. As a result, the adhesive composition for organic fiber cords in which the "aqueous urethane compound having a (C) (thermolabile blocked) isocyanate group" is the "aqueous urethane compound having a (C-2) (thermolabile blocked) isocyanate group" becomes more (3) having good adhesiveness between the organic fiber cord and the coating rubber composition, such a one.

[0099] <(D) Epoxide compound> The adhesive composition for organic fiber cords of the present invention (A) a synthetic rubber latex having an unsaturated diene, (B) gelatin, and (C) an aqueous compound having a (thermolabile blocked) isocyanate group, contains these, and does not contain resorcin and formaldehyde is characterized by, and further, (D) an epoxide compound, preferably contains.

[0100] The "(D) epoxy compound" refers to a compound having an oxacyclopropane (oxirane) (epoxy group), which is a three-membered ring ether, in its structural formula.

[0101] The "(D) epoxy compound" functions as a crosslinking agent component in the adhesive composition for organic fiber cords. That is, when the "(D) epoxy compound" is further contained in the adhesive composition of the present invention, crosslinking is introduced between the hydroxyl group, amine group, thiol group contained in the amino acid unit of "(B) gelatin" or the isocyanate group of "(C) (thermally dissociable blocked) aqueous compound having an isocyanate group", and remarkable performance improvement is seen in the improvement of the fracture resistance of the adhesive layer and the adhesive strength at high temperatures. Moreover, the "(D) epoxy compound" has an amine, alcohol, thiol, phenol, carboxylic acid, and it is preferable to mix and heat it with the "(C) (thermally dissociable blocked) aqueous compound having an isocyanate group". When such a "(D) epoxy compound" and a "(C) (thermally dissociable blocked) aqueous compound having an isocyanate group" are mixed and heated, crosslinking by a nucleophilic reaction with the amine, alcohol, thiol, phenol, carboxylic acid, or isocyanate (where the thermally dissociable block has dissociated) etc. that the "(D) epoxy compound" has is added to the adhesive composition for organic fiber cords mainly composed of urethane bonds, and creep and flow due to stress in the high temperature region are suppressed. Furthermore, it is preferable that the epoxy group of the "(D) epoxy compound" is polyfunctional. This is because the effect of the above suppression is enhanced, the fracture resistance of the adhesive layer by the adhesive composition for organic fiber cords of the present invention is further enhanced, and the adhesive strength at high temperatures is also higher.

[0102] The "(D) epoxy compound" is preferably a compound containing two or more epoxy groups in one molecule. Particularly preferably, it is a compound containing four or more epoxy groups in one molecule. The reason for this is that the epoxy group becomes polyfunctional, and as described above, the fracture resistance of the adhesive layer by the adhesive composition for organic fiber cords in the present invention is further enhanced, and the adhesive strength at high temperatures is also higher.

[0103] Specific examples of the "(D) epoxy compound" include, for example, reaction products of polyhydric alcohols such as diethylene glycol diglycidyl ether, polyethylene diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6 - hexanediol diglycidyl ether, glycerol polyglycidyl ether, trimethylolpropane polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, sorbitol polyglycidyl ether, etc. and epichlorohydrin; novolak - type epoxy resins such as phenol novolak - type epoxy resin and cresol novolak - type epoxy resin; bisphenol A - type epoxy resin, etc. Preferably, it is a reaction product of polyhydric alcohols and epichlorohydrin, or a novolak - type epoxy resin. For the sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, and novolak - type epoxy resin, commercially available chemicals can be used.

[0104] The "(D) epoxy compound" can be used by dissolving it in water or dispersing it in water by emulsification. For example, the "(D) epoxy compound" can be directly dissolved in water. Or, the "(D) epoxy compound" is dissolved in a small amount of solvent as needed, and the resulting solution is emulsified in water using a known emulsifier (for example, sodium alkylbenzene sulfonate, sodium dioctyl sulfosuccinate, nonylphenol ethylene oxide adduct, etc.) to obtain an emulsion.

[0105] Further, in certain embodiments of the adhesive composition for organic fiber cords of the present invention, the content (parts by mass) of the "(D) epoxy compound" is not particularly limited, but when the total of the parts by mass of (A) synthetic rubber latex having an unsaturated diene, (B) gelatin, and (C) aqueous compound having a (thermally dissociable blocked) isocyanate group is 100 parts by mass, it is preferably greater than 0 parts by mass and 50 parts by mass or less, more preferably greater than 0.2 parts by mass and 30 parts by mass or less.

[0106] <Method for producing an adhesive composition for organic fiber cords> The adhesive composition for organic fiber cords of the present invention (A) Synthetic rubber latex having an unsaturated diene, (B) Gelatin, and (C) Aqueous compound having a (thermally dissociable blocked) isocyanate group, characterized by comprising, but in producing the adhesive composition for organic fiber cords, (A) synthetic rubber latex having an unsaturated diene, (B) gelatin, (C) aqueous compound having a (thermally dissociable blocked) isocyanate group, can be mixed in any order.

[0107] The adhesive composition for organic fiber cords of the present invention is not particularly limited, but for example, after dissolving "(B) gelatin" in warm water, mixing this with "(A) synthetic rubber latex having an unsaturated diene" and cooling, and further mixing with "(C) aqueous compound having a (thermally dissociable blocked) isocyanate group", it can be produced. Preferably, after dissolving "(B) gelatin" in warm water at 40°C or higher and 80°C or lower, mixing this with "(A) synthetic rubber latex having an unsaturated diene" and cooling to a temperature of 15°C or higher and 65°C or lower, and further mixing with "(C) aqueous compound having a (thermally dissociable blocked) isocyanate group", it can be produced.

[0108] In addition, the mixing of "(A) synthetic rubber latex having an unsaturated diene" and "(B) gelatin" can also be carried out by mixing "(B) gelatin" as an emulsifier or post-additive with the raw materials of "(A) synthetic rubber latex having an unsaturated diene" in the manufacturing process of "(A) synthetic rubber latex having an unsaturated diene".

[0109] In the adhesive composition for organic fiber cords of the present invention, the mixing mass ratio of "(A) synthetic rubber latex having an unsaturated diene" and "(B) gelatin" is not particularly limited, but it is preferably in the range of 100:0.1 to 100:25, and more preferably in the range of 100:0.2 to 100:5 (including the mixing mass ratios at both ends). If the mixing mass ratio is 100:0.1 (if the ratio value is 1000 or less), a microcapsule film of "(B) gelatin" with a sufficient thickness can be formed around "(A) synthetic rubber latex having an unsaturated diene" as the core, and an adhesive layer with sufficient strength can also be obtained. In addition, if the mixing mass ratio is 100:25 (if the ratio value is 4 or more), the microcapsule film of "(B) gelatin" formed around "(A) synthetic rubber latex having an unsaturated diene" as the core does not become too thick, and when the coating rubber composition, which is the adherend of the organic fiber cord, and the adhesive composition for organic fiber cords are co-vulcanized and adhered, the coating rubber composition, which is the adherend, and "(A) synthetic rubber latex having an unsaturated diene" are well compatible. As a result, the initial process of adhesion between the coating rubber composition, which is the adherend, and the adhesive composition for organic fiber cords proceeds preferably.

[0110] In the mixing of "synthetic rubber latex having (A) unsaturated diene" and "(B) gelatin", in a normal coacervate, a known water-soluble material capable of strengthening the film made of "(B) gelatin" can be used in combination. For example, gum arabic, carrageenan, CM Cs, electrolyte substances composed of organic or inorganic salts, for example, salts having cations such as sodium chloride, potassium chloride, magnesium chloride, ammonium chloride, salts having anions such as sulfates, phosphates, carbonates, acetates can be used. Furthermore, a water-soluble liquid substance in which the film-forming material therein dissolves less than water, for example, alcohols such as ethanol and propanol, or water-soluble polymers such as isobutylene-maleic anhydride ring-opening copolymer salts can also be used.

[0111] In addition, it is also possible to mix a substance that crosslinks and insolubilizes gelatin. For example, aldehydes such as glutaraldehyde and transglutaminase enzymes can be used. However, if gelatin is excessively crosslinked and insolubilized, when the coated rubber composition, which is the adherend of the organic fiber cord, and the adhesive composition for organic fiber cord are co-vulcanized and adhered, the fluidity of the gelatin film on the surface of the rubber latex decreases, and the compatibility between the coated rubber composition, which is the adherend, and the "synthetic rubber latex having (A) unsaturated diene" is inhibited. As a result, the adhesiveness between the coated rubber composition, which is the adherend, and the adhesive composition for organic fiber cord may decrease.

[0112] In the adhesive composition for organic fiber cord of the present invention, the mixing mass ratio of "synthetic rubber latex having (A) unsaturated diene" and "(C) aqueous compound having (thermally dissociable blocked) isocyanate group" is not particularly limited, but it is preferably in the range of 100:5 to 100:300, more preferably in the range of 100:15 to 100:150, and even more preferably in the range of 100:20 to 100:60 (including the mixing mass ratios at both ends). If the mixing mass ratio is 100:5 (if the ratio value is 20 or less), the ratio of "(A) synthetic rubber latex having an unsaturated diene" in the adhesive composition for organic fiber cords does not become too large, and the adhesive layer resistance to breakage by the adhesive composition for organic fiber cords can be sufficiently maintained, and a decrease in adhesiveness under strain can be prevented. Also, if the mixing mass ratio is 100:300 (if the ratio value is 1 / 3 or more), the ratio of "(A) synthetic rubber latex having an unsaturated diene" in the adhesive composition for organic fiber cords does not become too low, and when co-vulcanizing and adhering the coating rubber composition, which is the adherend of the organic fiber cord, and the adhesive composition for organic fiber cords, the coating rubber composition, which is the adherend, and the "(A) synthetic rubber latex having an unsaturated diene" are favorably compatible. As a result, the adhesiveness between the coating rubber composition, which is the adherend, and the adhesive composition for organic fiber cords becomes sufficiently high.

[0113] Also, the adhesive composition for organic fiber cords of the present invention (A) synthetic rubber latex having an unsaturated diene, (B) gelatin, and (C) aqueous compound having a (thermally dissociable blocked) isocyanate group, characterized by containing, and further, (D) epoxy compound, although it is preferable to contain, when manufacturing the adhesive composition for organic fiber cords, (A) synthetic rubber latex having an unsaturated diene, (B) gelatin, (C) aqueous compound having a (thermally dissociable blocked) isocyanate group, (D) epoxy compound, can be mixed in any order.

[0114] However, when the "(D) epoxy compound" is mixed with water, the epoxy group tends to react with water and gradually lose its function as a crosslinking agent. Therefore, after mixing the "(D) epoxy compound" with water, it is preferable to subject the adhesive composition for organic fiber cords to the coating treatment of the organic fiber cords as soon as possible. Specifically, after mixing the "(D) epoxy compound" with water, it is more preferable to subject the adhesive composition for organic fiber cords to the coating treatment of the organic fiber cords within 1 to 2 days.

[0115] Moreover, the (A) synthetic rubber latex having an unsaturated diene, (B) gelatin, (C) an aqueous compound having a (thermally dissociable blocked) isocyanate group, and (D) an epoxy compound are preferably aqueous. This is because water, which causes less environmental pollution, can be used as a solvent.

[0116] <Organic fiber cord - rubber composite> The organic fiber cord - rubber composite of the present invention will be described in detail with reference to FIG. 4.

[0117] FIG. 4 is a schematic cross-sectional view showing an example of the organic fiber cord - rubber composite of the present invention in an embodiment of the present invention. In the organic fiber cord - rubber composite 31, the outer surface of the organic fiber cord 1 in the outer diameter direction is coated with an adhesive layer 32 made of the adhesive composition for organic fiber cords 2 of the present invention. Then, the organic fiber cord 1 is further adhered to a coating rubber composition 33 on the outer side in the outer diameter direction thereof via the adhesive 32 made of the adhesive composition for organic fiber cords 2 of the present invention, and the organic fiber cord - rubber composite 31 of the present invention is formed.

[0118] In addition, the form of the rubber reinforcing material using the adhesive composition for organic fiber cords of the present invention can be in the form of a film, short fibers, non-woven fabric, etc. in addition to the organic fiber cord - rubber composite.

[0119] <<Organic fiber cord of organic fiber cord - rubber composite>> The organic fiber cord that constitutes the organic fiber cord-rubber composite of the present invention is as described in <organic fiber cord>.

[0120] <<Coating rubber composition of organic fiber cord-rubber composite>> On the other hand, the coating rubber composition that constitutes the organic fiber cord-rubber composite of the present invention preferably contains compounding agents commonly used in the rubber industry in the rubber component. Here, the rubber component is not particularly limited. For example, in addition to natural rubber, conjugated diene synthetic rubbers such as polyisoprene rubber (IR), polybutadiene rubber (BR), styrene-butadiene copolymer rubber (SBR), acrylonitrile-butadiene rubber (NBR), chloroprene rubber (CR), and butyl rubber (IIR), and furthermore, ethylene-propylene copolymer rubber (EPM), ethylene-propylene-diene copolymer rubber (EPDM), polysiloxane rubber, etc. are mentioned. Among these, natural rubber and conjugated diene synthetic rubbers are preferred. Also, these rubber components may be used alone or in combination of two or more.

[0121] <<Manufacturing method of organic fiber cord-rubber composite>> The organic fiber cord-rubber composite of the present invention is manufactured by coating an organic fiber cord with the adhesive composition for organic fiber cord according to the present invention to form an adhesive layer, and co-vulcanizing and adhering "(A) synthetic rubber latex having an unsaturated diene" in the adhesive composition for organic fiber cord and the rubber component in the coating rubber composition which is the adherend of the organic fiber cord.

[0122] The method for coating the organic fiber cord with the adhesive composition for organic fiber cord according to the present invention is not particularly limited. For example, a method of immersing the organic fiber cord in the adhesive composition for organic fiber cord, a method of applying the adhesive composition for organic fiber cord to the organic fiber cord with a brush, a method of spraying the adhesive composition for organic fiber cord onto the organic fiber cord, etc. can be used, and an appropriate method can be selected as needed.

[0123] When coating the organic fiber cord with the adhesive composition for organic fiber cord, it is preferable to dissolve the adhesive composition for organic fiber cord in various solvents to lower the viscosity, because the coating becomes easier. It is environmentally preferable that the solvent for lowering the viscosity of the adhesive composition for organic fiber cord mainly consists of water.

[0124] Here, the thickness of the adhesive layer formed by the adhesive composition for organic fiber cord is not particularly limited, but is preferably 50 μm or less, and more preferably 0.5 μm or more and 30 μm or less. In addition, when the adhesion amount of the adhesive composition due to the adhesion treatment becomes thick, the adhesion durability under tire rolling tends to decrease. The reason for this is that the adhesive composition at the interface of the fiber material to be adhered bears the stress due to strain and thus has relatively little deformation because the fiber material has high rigidity, but the deformation due to strain increases as it moves away from the interface. Since the adhesive composition contains more thermosetting condensates than the adhered rubber material, it is hard but brittle, and thus the adhesion fatigue under repeated strain tends to increase. From the above, the average thickness of the adhesive composition layer is preferably 50 μm or less, and more preferably 0.5 μm or more and 30 μm or less. Also, the concentration of the adhesive composition for organic fiber cord impregnated in the organic fiber cord is not particularly limited, but is preferably 5.0% by mass or more and 25.0% by mass or less, and more preferably 7.5% by mass or more and 20.0% by mass or less (both are values in terms of solid content), based on the mass of the organic fiber cord.

[0125] The organic fiber cord coated with the adhesive composition for organic fiber cord is preferably heat-treated at a temperature of 100°C or higher and 210°C or lower, and then at a temperature equal to or higher than the glass transition temperature of the polymer chain of the organic fiber cord (typically, [melting temperature: -70°C] of the polymer chain) and equal to or lower than [melting temperature: -10°C]. The favorable reason is that if it is at or above the glass transition temperature of the polymer chain of the organic fiber cord, the molecular mobility of the polymer chain of the organic fiber cord becomes good, and the adhesion promoter ((C) a water-based compound having a (thermally dissociable blocked) isocyanate group) in the adhesive composition for the organic fiber cord and the polymer chain of the organic fiber cord can interact sufficiently, so that sufficient adhesive force can be obtained between the adhesive composition for the organic fiber cord and the organic fiber cord. The organic fiber cord may be one that has been pre-treated by electron beam, microwave, corona discharge, plasma treatment or the like.

[0126] In the organic fiber cord-rubber composite of the present invention, the resin material may be in any form such as a film, cord, cable, filament, filament chip, cord fabric, canvas, etc. Particularly for reinforcing rubber articles such as tire articles and conveyor belts, a cord formed by twisting a plurality of filaments is preferably used as the resin. Further, such a cord preferably has a synthetic fiber with S-twist and Z-twist, the twist coefficient of the Z-twist being 1,300 to 2,500, and the twist coefficient of the S-twist being 900 to 1,800. In the present invention, it is preferable that the organic fiber cord is a tire cord of polyethylene terephthalate with a twist structure of 1670 dtex / 2, an S-twist number of 40 turns / 10 cm, and a Z-twist number of 40 turns / 10 cm, and the adhesive composition for the organic fiber cord is adhered to the tire cord with respect to the mass of the tire cord, which is an organic fiber cord-rubber composite.

[0127] Finally, the organic fiber cord coated with the adhesive composition for the organic fiber cord is adhered by co-vulcanizing (A) a synthetic rubber latex having an unsaturated diene in the adhesive composition for the organic fiber cord and a rubber component in the coating rubber composition which is the adherend of the organic fiber cord.

[0128] In the case of the co-vulcanization of the rubber component in the coating rubber composition, for example, sulfur, tellurium polysulfide compounds such as tetramethyl tellurium disulfide and dipentamethylene tellurium tetrasulfide, and organic vulcanizing agents such as 4,4-dithiomorpholine, p-quinonedioxime, p,p'-dibenzoylquinonedioxime, and cyclic sulfur imide can be mentioned. Among them, it is preferable to use sulfur. Further, various compounding agents such as fillers such as carbon black, silica, and aluminum hydroxide, vulcanization accelerators, anti-aging agents, and softeners that are usually used in the rubber industry can be appropriately compounded in the rubber component in the coating rubber composition.

[0129] In addition, in the adhesive method for an organic fiber cord, wherein the vulcanizing agent contained in the adherend of a synthetic resin material such as an organic fiber cord and / or the adherend of the coating rubber composition migrates to the adhesive composition for an organic fiber cord, and the adhesive composition for an organic fiber cord is crosslinked by the migrated vulcanizing agent, it goes without saying that the effect of adhesion can be obtained.

[0130] <Tire> The tire of the present invention uses the organic fiber cord-rubber composite of the present invention.

[0131] The adhesive composition for an organic fiber cord and the organic fiber cord-rubber composite of the present invention can be applied not only to the tire but also to all rubber articles such as conveyor belts, belts, hoses, and air springs.

Examples

[0132] Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples at all.

[0133] <Preparation of (A-1) Vinylpyridine-Styrene-Butadiene Copolymer Latex> In the following Comparative Examples and Examples, as the synthetic rubber latex having an unsaturated diene, (A-1) a vinylpyridine-styrene-butadiene copolymer latex was prepared and used as follows in accordance with Comparative Example 1 described in JP-A-9-78045. 130 parts by mass of deionized water and 4.0 parts by mass of potassium rosinate were charged and dissolved in a 5-liter autoclave purged with nitrogen. To this, a monomer mixture having a composition of 15 parts by mass of vinylpyridine monomer, 15 parts by mass of styrene, and 70 parts by mass of butadiene, and 0.60 parts by mass of t-dodecyl mercaptan were charged and emulsified. Then, the temperature was raised to 50°C, 0.5 parts by mass of potassium persulfate was added, and polymerization was initiated. After the reaction rate of the monomer mixture reached 90%, 0.1 parts by mass of hydroquinone was added to stop the polymerization. Next, unreacted monomers were removed under reduced pressure to obtain an (A-1) vinylpyridine-styrene-butadiene copolymer latex having a solid content concentration of 41%.

[0134] <Preparation of (B-1) Porcine Skin Gelatin> In the following Comparative Examples and Examples, as the gelatin (B), (B-1) porcine skin gelatin was prepared and used as follows. 30 g of porcine skin gelatin having a gelation temperature of 23 to 30°C (high-grade gelatin M.W. 8,000 ± 2,000, manufactured by Fujifilm Wako Pure Chemical Corporation) was mixed in a 500-ml flask with 270 g of deionized warm water until completely dissolved to produce a storage solution of gelatin having a solid content concentration of 10%. Then, the solution was warmed and maintained at 40°C to obtain (B-1) porcine skin gelatin.

[0135] <Preparation of a Water-Dispersible (Thermally Dissociable Blocked) Isocyanate Compound, Which is an Addition Product of a Polyisocyanate Having an Aromatic Ring and a Blocker Having One or More Active Hydrogen Groups> In the following comparative examples and examples, as the water-dispersible (thermally dissociable blocked) isocyanate compound, which is an addition product of a polyisocyanate having an (C-1) aromatic ring of an aqueous compound having a (C) (thermally dissociable blocked) isocyanate group and a blocking agent having one or more active hydrogen groups, DM-6400 (blocking agent thermal dissociation temperature: about 130 ° C, solid content concentration: 25% by mass) manufactured by Meisei Chemical Industry Co., Ltd., which is a blocked product of methylene diphenyl diisocyanate, was used as it was.

[0136] <Preparation of an aqueous urethane compound having a (C-2) (thermally dissociable blocked) isocyanate group> In the following comparative examples and examples, as the aqueous urethane compound having a (C-2) (thermally dissociable blocked) isocyanate group of an aqueous compound having a (C) (thermally dissociable blocked) isocyanate group, a (C-2-1) thermoreactive aqueous urethane resin was produced according to the description of Example (6) in JP-A-58-49770. That is, 100 parts by mass of polyphenylene polymethylene polyisocyanate (NCO content: 31.5% by mass) and 24.4 parts by mass of an ethylene oxide 2-mol adduct of bisphenol A (hydroxyl value = 35.4) were reacted at 85 ° C for 30 minutes in a flask equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, a thermometer and a dropping funnel to obtain a urethane prepolymer having a free isocyanate of 20.7% by mass. Next, 62.2 parts by mass of dioxane, 72 parts by mass of p-sec-butyl-phenol and 0.25 part by mass of triethylamine were added at 50 ° C, and then the reaction was carried out at 75 ° C for 120 minutes in the system to obtain a partially blocked prepolymer having a free isocyanate of 4.2% by mass based on the total of polyphenylene polymethylene polyisocyanate and the ethylene oxide 2-mol adduct of bisphenol A. Next, 55 parts of an aqueous solution of sodium taurine with a concentration of 30% by mass was added at a system temperature of 40 ° C and reacted at 40 to 45 ° C for 30 minutes. Thereafter, water dilution and removal of dioxane were carried out so that the solid content became 31% to obtain a (C-2-1) thermoreactive aqueous urethane resin.

[0137] Also, as the (C-2-2) thermoreactive aqueous urethane resin, which is an aqueous urethane compound having a (C)(thermolabile blocked) isocyanate group and is another aqueous compound having a (C-2)(thermolabile blocked) isocyanate group, Elastron BN77 (blocking agent thermal dissociation temperature: about 160 °C, pH: 8.0, solid content concentration: 31% by mass) manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. was used as it was.

[0138] <Preparation of (D-1) sorbitol polyglycidyl ether> In the following comparative examples and examples, as the (D) epoxy compound, Denacol EX-614B (molecular weight: 949, epoxy equivalent: 173, solid content concentration: 100% by mass) manufactured by Nagase ChemteX Corporation, which is (D-1) sorbitol polyglycidyl ether, was used as it was.

[0139] <Preparation of Adhesive Compositions for Organic Fiber Cords in Comparative Examples and Examples> <<Preparation of RFL (resorcinol-formaldehyde-latex) Adhesive Composition (Comparative Example 1)>> With the composition shown in Table 1 below, each chemical was mixed and aged at room temperature for 7 hours to obtain a resorcinol-formaldehyde aged solution.

Table 1

[0140] Subsequently, 370.51 parts by mass of the (A-1) vinylpyridine-styrene-butadiene copolymer latex was added to 629.49 parts by mass of the resorcinol-formaldehyde aging solution, and then aged at room temperature for 16 hours to obtain a conventional RFL (resorcinol-formaldehyde-latex) adhesive composition (Comparative Example 1) having a solid content concentration of 18% by mass.

[0141] <<Preparation of latex adhesive composition (Comparative Example 2)>> The (A-1) vinylpyridine-styrene-butadiene copolymer latex and water were mixed with the amounts adjusted so that the solid content concentration was 18% by mass, and then stirred well to obtain a latex adhesive composition (Comparative Example 2).

[0142] <<Preparation of latex-gelatin adhesive composition (Comparative Example 3)>> The (A-1) vinylpyridine-styrene-butadiene copolymer latex and the (B-1) porcine skin gelatin were blended as shown in Table 3, and the amounts were adjusted with water so that the solid content concentration of the adhesive composition was 18% by mass, and then stirred well to obtain a latex-gelatin adhesive composition (Comparative Example 3).

[0143] <<Preparation of latex-aqueous urethane adhesive composition (Comparative Example 4)>> The (A-1) vinylpyridine-styrene-butadiene copolymer latex and the (C-2-1) thermoreactive aqueous urethane resin were blended as shown in Table 3, and the amounts were adjusted with water so that the solid content concentration of the adhesive composition was 18% by mass, and then stirred well to obtain a latex-aqueous urethane adhesive composition (Comparative Example 4).

[0144] <<Preparation of adhesive composition for organic fiber cord (Examples 1 to 5) which is an embodiment of the present invention>> As shown in Table 3, a synthetic rubber latex having each predetermined (A) unsaturated diene, (B) gelatin, (C) an aqueous compound having a (thermally dissociable blocked) isocyanate group (Examples 1 to 5), and (D) an epoxide compound (Example 3) were blended in this order, and the amount was adjusted with water so that the solid content concentration of the adhesive composition was 18% by mass, and then mixed and sufficiently stirred to obtain an adhesive composition for organic fiber cords (Examples 1 to 5) which is one embodiment of the present invention. Note that, as the aqueous urethane compound having a (C-2) (thermally dissociable blocked) isocyanate group, (C-2-1) a thermally reactive aqueous urethane resin was used in Examples 1 to 3, (C-2-2) a thermally reactive aqueous urethane resin was used in Example 4, and a blocked body of (C-1-1) methylene diphenyl isocyanate was used in Example 5.

[0145] In the mixing when preparing Comparative Example 3 and Examples 1 to 5 above, after adding (B) gelatin, the mixed solution was warmed and held at 40°C to 70°C for 1 minute or more and 1 hour or less, and then gradually cooled to 20°C.

[0146] <Coating of the tire cord with each adhesive composition for organic fiber cords> As the organic fiber cord, a tire cord made of polyethylene terephthalate having a twist structure of 1670 dtex / 2, a number of twists in the upper direction of 40 turns / 10 cm, and a number of twists in the lower direction of 40 turns / 10 cm was used. The tire cord was immersed in each adhesive composition for organic fiber cords of Comparative Examples 1 to 4 and Examples 1 to 5 so that the concentration of the adhesive composition for organic fiber cords impregnated in the tire cord was 3.8% by mass with respect to the mass of the organic fiber cord. Then, it was dried in a drying zone (150°C, 60 seconds), subjected to thermal curing of the resin while applying tension (0.8 kg / cord) in a hot zone, and thermal curing while relaxing the tension in a normalization zone (240°C, 60 seconds) to obtain tire cords coated with each adhesive composition for organic fiber cords of Comparative Examples 1 to 4 and Examples 1 to 5.

[0147] <Formation of tire cord - rubber composite> The tire cords coated with the adhesive compositions for each of the organic fiber cords of Comparative Examples 1 to 4 and Examples 1 to 5 were embedded in the unvulcanized compounded rubber composition shown in Table 2 below and co-vulcanized at 155 °C for 20 minutes. As the coated rubber component, a rubber composition containing natural rubber, styrene-butadiene rubber, carbon black, vulcanizing chemicals, etc. was used.

[0148] <Workability Evaluation of Adhesive Composition for Organic Fiber Cord> Regarding the workability of the adhesive compositions for each of the organic fiber cords of Comparative Examples 1 to 4 and Examples 1 to 5, the following evaluations were conducted.

[0149] <<Evaluation of Mechanical Stability (Coagulation Rate)>> The mechanical stability (coagulation rate) of the adhesive compositions for each of the organic fiber cords of Comparative Examples 1 to 4 and Examples 1 to 5 was measured in accordance with the method using a Maron type mechanical stability tester (manufactured by Kumagai Riki Kogyo Co., Ltd., Maron stability tester No. 2312-II) for copolymer latex compositions shown in JIS K6392-1995. Briefly, for the adhesive compositions for each of the organic fiber cords of Comparative Examples 1 to 4 and Examples 1 to 5, after applying a shear strain at a compression load of 10 Kg and a rotation speed of 1000 r / min for 10 minutes using the rotor of the Maron type mechanical stability tester, the coagulation rate % was evaluated from the amount of coagulated matter generated by the following formula. Coagulation rate % = (dry mass of the generated coagulated matter) / (solid content mass of the test adhesive liquid) × 100

[0150] <<Evaluation of Adhesion to the Drawing Roll>> The polyethylene terephthalate tire cord, which is an organic fiber cord, was continuously processed for 2000 m in an immersion treatment machine storing the adhesive compositions for each of the organic fiber cords of Comparative Examples 1 to 4 and Examples 1 to 5. The amount of the adhesive compositions for each of the organic fiber cords of Comparative Examples 1 to 4 and Examples 1 to 5 adhering to the drawing roll was visually observed and evaluated in the following 5 grades. Extra-large: Particularly a lot, Large: A lot, Medium: Medium degree, Small: Little, Very small: Very little.

[0151] <Evaluation of Adhesion of Adhesive Composition for Organic Fiber Cord> Regarding the adhesiveness of the adhesive compositions for organic fiber cords of Comparative Examples 1 to 4 and Examples 1 to 5, the following evaluations were conducted.

[0152] <<Evaluation of Adhesive Strength>> By pulling the tire cord - rubber composite obtained using the adhesive compositions for organic fiber cords of Comparative Examples 1 to 4 and Examples 1 to 5 at a speed of 300 mm / min, the tire cord was peeled from the tire cord - rubber composite, and the peeling resistance per tire cord was determined and taken as the adhesive strength (N / cord).

[0153] <<Evaluation of Coated Rubber Adhesion State>> Regarding the tire cord peeled from the above tire cord - rubber composite, the adhesion state of the coated rubber was visually observed and scored according to Table 2 below.

Table 2

[0154] <Results of Workability Evaluation and Adhesion Evaluation of Adhesive Composition for Organic Fiber Cord> The formulations of the adhesive compositions for organic fiber cords of Comparative Examples 1 to 4 and Examples 1 to 5, and the results of their workability evaluation and adhesion evaluation are shown in Table 3 below.

Table 3

[0155] <Columns of Adhesive Composition for Organic Fiber Cord> A - 1: (A - 1) Vinylpyridine - styrene - butadiene copolymer latex B - 1: (B - 1) Pigskin gelatin C - 1 - 1: (C - 1 - 1) Block body of methylenediphenyl diisocyanate C - 2 - 1: (C - 2 - 1) Thermoreactive aqueous urethane resin C - 2 - 2: (C - 2 - 2) Thermoreactive aqueous urethane resin D-1: (D-1) Sorbitol polyglycidyl ether R: (R) Resorcinol F: (F) Formaldehyde solution N: (N) Sodium hydroxide -: Represents the absence of addition of this component. Each numerical value: Represents the dry mass parts of this component.

[0156] The conventional RFL adhesive composition for organic fiber cords containing resorcinol and formaldehyde (Comparative Example 1) was relatively good in terms of workability represented by mechanical stability (coagulation rate) and adhesiveness to the drawing roll, but was insufficient in terms of adhesiveness represented by adhesive strength and the adhesion state of the coating rubber. On the other hand, the adhesive compositions for organic fiber cords not containing resorcinol and formaldehyde (Comparative Examples 2, 3, and 4), which were intended to reduce the environmental load, resulted in insufficient workability represented by mechanical stability (coagulation rate) and adhesiveness to the drawing roll, and also resulted in insufficient adhesiveness represented by adhesive strength and the adhesion state of the coating rubber.

[0157] In contrast, Examples 1 to 5, which are some embodiments of the adhesive composition for organic fiber cords of the present invention not containing resorcinol and formaldehyde, showed good results in both workability represented by mechanical stability (coagulation rate) and adhesiveness to the drawing roll, and adhesiveness represented by adhesive strength and the adhesion state of the coating rubber. Notably, the adhesive compositions for organic fiber cords containing both (B-1) porcine skin gelatin and (C-2-1) thermoreactive aqueous urethane resin (Examples 1 and 2) had both characteristics of workability represented by mechanical stability (coagulation rate) and adhesiveness to the drawing roll, and adhesiveness represented by adhesive strength and the adhesion state of the coating rubber synergistically and significantly improved compared to both the adhesive composition for organic fiber cords containing (B-1) porcine skin gelatin but not containing (C-2-1) thermoreactive aqueous urethane resin (Comparative Example 3), and the adhesive composition for organic fiber cords not containing (B-1) porcine skin gelatin but containing (C-2-1) thermoreactive aqueous urethane resin (Comparative Example 4). These synergistic improvement effects were observed regardless of whether (C-2-2) a thermoreactive aqueous urethane resin (Example 4) or (C-1-1) a blocked product of methylenediphenyl diisocyanate (Example 5) was used, including in partial cases. Furthermore, in the adhesive composition for organic fiber cords containing (D-1) sorbitol polyglycidyl ether (Example 3), the adhesiveness represented by the adhesive strength and the adhesion state of the coating rubber was further improved (Examples 1, 2 vs. 3).

Industrial Applicability

[0158] According to the present invention, (1) By not using resorcinol and formaldehyde, the environmental load is low, (2) By suppressing the tackiness of the rubber latex measured as the mechanical stability of the adhesive liquid under shear strain, it becomes possible to suppress the adhesion of the adhesive composition for organic fiber cords to rolls, etc. in the process of coating the organic fiber cords with the adhesive composition for organic fiber cords and drying and thermosetting them, and the workability is good. (3) The adhesiveness between the organic fiber cord and the coating rubber composition is good. An adhesive composition for organic fiber cords that provides the above effects is provided. In addition, an organic fiber cord-rubber composite using the organic fiber cord coated with the adhesive composition for organic fiber cords, and a tire using the organic fiber cord-rubber composite are also provided. Therefore, the present invention can be used in the industrial field of manufacturing rubber articles such as tires.

Explanation of Symbols

[0159] 1: Organic fiber cord 2: Adhesive composition for organic fiber cords 3: Dipping bath 4: Organic fiber cord coated with the adhesive composition for organic fiber cords 2 5: Squeezing roll 6: Drying zone 7: Hot zone 8: Normalizing zone 11: Synthetic rubber latex having an unsaturated diene 12: Gelatin 13: Aqueous urethane compound having (thermally dissociable blocked) isocyanate groups 14: Activated isocyanate group 15: Portion easily diffusible into the organic fiber cord 1 16: Portion difficult to diffuse into the organic fiber cord 1 20: Latex-gelatin protective film effect 21: Rubber co-vulcanization adhesion 22: Gelatin-isocyanate crosslinking 23: Activated isocyanate crosslinking 24: Aqueous urethane-organic fiber cord interface effect 31: Organic fiber cord-rubber composite 32: Adhesive layer by the adhesive composition 2 for the organic fiber cord 33: Coating rubber composition 40: A water-dispersible (thermally dissociable blocked) isocyanate compound which is an addition product of a polyisocyanate having an aromatic ring and a blocking agent having one or more active hydrogen groups 41: Aromatic isocyanate-organic fiber cord diffusion effect

Claims

1. An adhesive composition for organic fiber cords, comprising: (A) a synthetic rubber latex having an unsaturated diene, (B) gelatin, and (C) an aqueous compound having a (thermally dissociable blocked) isocyanate group, wherein the mixing mass ratio of the synthetic rubber latex having an unsaturated diene (A) to the gelatin (B) is in the range of 100:0.2 to 100:5, and resorcinol and formaldehyde are not included.

2. Furthermore, (D) an epoxy compound is included. The adhesive composition for organic fiber cords according to Claim 1, characterized in that.

3. The aqueous compound having a (thermally dissociable blocked) isocyanate group (C) is (C-1) a water-dispersible (thermally dissociable blocked) isocyanate compound which is an addition product of a polyisocyanate having an aromatic ring and a blocking agent having one or more active hydrogen groups, The adhesive composition for organic fiber cords according to Claim 1 or 2, wherein.

4. The aqueous compound having a (thermally dissociable blocked) isocyanate group (C) is (C-2) an aqueous urethane compound having a (thermally dissociable blocked) isocyanate group, The adhesive composition for organic fiber cords according to Claim 1 or 2, wherein.

5. The water-dispersible (thermally dissociable blocked) isocyanate compound which is an addition product of the polyisocyanate having an aromatic ring (C-1) and the blocking agent having one or more active hydrogen groups is a blocked product of methylene diphenyl diisocyanate. The adhesive composition for organic fiber cords according to Claim 3, characterized in that.

6. The aqueous urethane compound having a (thermally dissociable blocked) isocyanate group (C-2) is (α) an organic polyisocyanate compound having 3 or more and 5 or less functional groups and a number average molecular weight of 2,000 or less, (β) a compound having 2 or more and 4 or less active hydrogen groups and a number average molecular weight of 5,000 or less, (γ) a thermally dissociable blocking agent, and (δ) a compound having at least one active hydrogen group and at least one hydrophilic group which is anionic, cationic, or nonionic, wherein the mixing ratios of (α), (β), (γ), and (δ) with respect to the total amount of (α), (β), (γ), and (δ) are for (α), 40% by mass or more and 85% by mass or less, for (β), 5% by mass or more and 35% by mass or less, for (γ), 5% by mass or more and 35% by mass or less, and for (δ), 5% by mass or more and 35% by mass or less. which is a reaction product after mixing and reacting so as to become, and when the molecular weight of the isocyanate group (-NCO) is 42, the constituent ratio of the (thermally dissociable blocked) isocyanate group in the reaction product is 0.5% by mass or more and 11% by mass or less, The adhesive composition for organic fiber cords according to claim 4, characterized in that.

7. The aqueous urethane compound having the (C-2) (thermally dissociable blocked) isocyanate group is represented by the following general formula (I) 【Chemical 1】 (In formula (I), A is a residue obtained by elimination of an active hydrogen group from an organic polyisocyanate compound, X is a residue obtained by elimination of an active hydrogen group from a polyol compound having 2 or more and 4 or less hydroxyl groups and a number average molecular weight of 5,000 or less, Y is a residue obtained by elimination of an active hydrogen group from a thermally dissociable blocking agent, Z is a residue obtained by elimination of an active hydrogen group from a compound having at least one active hydrogen group and at least one group that forms a salt or a hydrophilic polyether chain, n is an integer of 2 or more and 4 or less, p + m is an integer of 2 or more and 4 or less (m ≧ 0.25), represents), The adhesive composition for organic fiber cords according to claim 4, characterized in that it is represented by.

8. The adhesive composition for organic fiber cords according to any one of claims 2 to 7, characterized in that the (D) epoxy compound has 2 or more epoxy groups in one molecule.

9. The adhesive composition for organic fiber cords according to any one of claims 2 to 8, characterized in that the (D) epoxy compound is a reaction product of polyhydric alcohols and epichlorohydrin.

10. An organic fiber cord-rubber composite using an organic fiber cord coated with the adhesive composition for organic fiber cords according to any one of claims 1 to 9.

11. A tire using the organic fiber cord-rubber composite according to claim 10.

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