JP2022039261A - Adhesion treating agent for rubber and fiber, and synthetic fiber cord for reinforcing rubber using the same - Google Patents

Abstract

To provide an adhesion treating agent for rubber and fiber, which has drastically improved heat-resistant adhesive property and durability in rubber, sufficient adhesive strength for practical use, excellent process passability, and excellent storage stability thereof, a production method thereof, a synthetic fiber code for reinforcing rubber formed by attaching an adhesive to synthetic fiber, and a rubber product including the synthetic fiber code for reinforcing rubber.SOLUTION: An adhesion treating agent for rubber and fiber is characterized as including at least a halogenated phenol derivative (A) and a blocked isocyanate compound (B), in which a weight ratio of (solid content of A):(solid content of B) is 50:50-80:20, and a content of a solid portion of the halogenated phenol derivative (A) in 100 wt.% of the total solid is 30-60 wt.%.SELECTED DRAWING: None

Description

The present invention relates to an adhesive treatment agent for synthetic fibers and a method for producing the same, which improves the adhesiveness between rubber and synthetic fibers, a synthetic fiber cord for rubber reinforcement in which this adhesive adheres to synthetic fibers, and a synthetic fiber for rubber reinforcement. It relates to rubber products containing fiber cords.

Synthetic fibers such as nylon fibers, polyester fibers, and aromatic polyamide fibers have been widely used as reinforcing materials in rubber products such as tires, hoses, and belts. However, when it is used as a reinforcing material by being embedded in a rubber product, it is exposed to high temperatures due to the heat generated by the rubber, and due to repeated expansion and compression and bending, the adhesiveness between the rubber and the synthetic fiber deteriorates. The strength of synthetic fibers was reduced, which was a factor leading to the failure of rubber products. In recent years, there has been an increasing need for improving the durability of rubber products in order to reduce the frequency of failure replacement of rubber products from the viewpoint of environmental protection.

As a technique disclosed for the above problem, for example, there is a prior art of Patent Documents 1 to 4.

Patent Document 1 discloses a code having an impregnation degree of RFL adhesive of 3.5 to 9%.

Patent Document 2 is coated with a first treatment agent containing three kinds of an aliphatic epoxide compound, a blocked polyisocyanate compound, and a vinylpyridine, styrene, and butadiene rubber latex having a glass transition point of −30 to 0 ° C. Resolvin as its outer layer
A polyester fiber cord for rubber reinforcement coated with a second treatment agent containing formalin rubber latex (RFL), and the first bath hot stretch tension is treated with 0.05 to 0.40 cN / dtex. Disclosed is a method for producing a polyester fiber cord for rubber reinforcement, which is characterized by the above.

In Patent Document 3, a multi-twist cord having a lower twist and an upper twist, a lower twist twist coefficient of 1000 to 2500, and an upper twist twist coefficient of 1500 to 3600 includes resorcin, formalin, and rubber latex (RFL). Disclosed is an organic fiber cord coated with an adhesive, characterized in that the cord compressibility is 83 to 97% and the RFL impregnation degree inside the cord is 10 to 50%. ing.

Patent Document 4 describes at least one component selected from the group consisting of polyphenols, chlorphenol resin and lignin resin, and at least one selected from a water-soluble polymer other than the above component or a water-dispersible polymer other than the above component. Disclosed is an adhesive for organic fibers containing one component.

Japanese Patent Publication No. 2014-530302 Japanese Unexamined Patent Publication No. 2013-76186 JP-A-2017-150105 WO2018 / 003572

However, according to Patent Document 1, although the fatigue resistance is improved, the adhesive strength is not sufficient. According to Patent Documents 2 and 3, the adhesive strength and fatigue resistance are also improved as compared with the conventional ones, but the durability is not sufficient as the required level increases. According to Patent Document 4, the initial adhesive strength is improved, but the heat-resistant adhesive strength and durability are not sufficient.

The present invention has been made as a result of studying the solution of the above-mentioned problems in the prior art as a problem.

An object of the present invention is a rubber that has little adhesive deterioration under high temperature for a long time while being embedded in rubber of a tire, belt, hose, etc., and suppresses deterioration when repeatedly stretched and compressed in the rubber. -To provide an adhesive treatment agent for fibers and a synthetic fiber cord for rubber reinforcement.

The present invention employs the following means in order to solve such a problem. That is,
(1) It contains at least the halogenated phenol derivative (A) and the blocked isocyanate compound (B), and the weight ratio of (solid content of A): (solid content of B) is 50:50 to 80:20, and An adhesive treatment agent for rubber / fiber, wherein the content of the solid content of the halogenated phenol derivative (A) in 100% by weight of the total solid content is 30 to 60% by weight.

(2) The first aspect of the present invention is that the rubber latex (C) is further contained, and the weight ratio of (solid content of A + solid content of B): (solid content of C) is 80:20 to 60:40. Adhesive treatment agent for rubber and fiber described in.

(3) Claim 1 or claim 1, further comprising resorcin-formaldehyde resin (D), wherein the content of resorcin-formaldehyde resin (D) in 100% by weight of the total solid content is 2.4% by weight or less. The adhesive treatment agent for rubber / fiber according to 2.

(4) One of claims 1 to 3, wherein the liquid viscosity of the adhesive treatment agent 240 hours after the adjustment is 5% or less as compared with the liquid viscosity of the adhesive treatment agent immediately after the adjustment. The described adhesive treatment agent for rubber and fiber.

(5) The method for producing an adhesive for rubber / fiber according to any one of claims 1 to 4, wherein the aging time after adjustment is 1 hour or less. A method for manufacturing a treatment agent.

(6) A synthetic fiber cord for rubber reinforcement, which comprises a synthetic fiber to which the adhesive treatment agent for rubber / fiber according to any one of claims 1 to 4 is attached.

(7) The synthetic fiber cord for rubber reinforcement according to claim 6, wherein an adhesive treatment agent containing resorcin, formalin, and rubber latex (RFL) is further adhered.

(8) The synthetic fiber cord for rubber reinforcement according to claim 6 or 7, wherein the amount of solid content adhered to the adhesive treatment agent for rubber / fiber is 1 to 2.9% by weight with respect to the synthetic fiber.

(9) The synthetic fiber cord for rubber reinforcement according to any one of claims 6 to 8, wherein the synthetic fiber contains at least one selected from nylon fiber, polyester fiber, and aromatic polyamide fiber.

(10) A rubber product containing the synthetic fiber cord for rubber reinforcement according to any one of claims 6 to 9.

According to the present invention, a synthetic fiber cord for rubber reinforcement having significantly improved heat-resistant adhesiveness when exposed to high temperature for a long time and fatigue resistance in a high-temperature atmosphere during a rubber vulcanization process or use of a rubber product can be obtained. Further, the process passability at the time of manufacturing a rubber product using the synthetic fiber cord for rubber reinforcement obtained in the present invention and the storage stability of the adhesive treatment agent are improved. The rubber product reinforced with the synthetic fiber cord for rubber reinforcement according to the present invention can withstand harsh specifications for a longer time than before when used as a tire, belt, or hose.

It is a schematic diagram which shows the friction tester which evaluates the process passability of a synthetic fiber cord for rubber reinforcement.

The present invention will be described in detail below.

The adhesive treatment agent for rubber / fiber of the present invention contains at least a halogenated phenol derivative (A) and a blocked isocyanate compound (B), and the weight ratio of (solid content of A): (solid content of B) is 50 :. It is necessary that the content is 50 to 80:20 and the solid content of the halogenated phenol derivative (A) in 100% by weight of the total solid content is 30 to 60% by weight.

Examples of the halogenated phenol derivative (A) used in the present invention include a condensate obtained by condensing a phenolic compound containing a halogenated phenol compound with formaldehyde, and a compound containing the following chemical formula as a main component is preferably mentioned. ..

However, in the formula, X is Cl or Br, Y and Z are Cl, Br, H, OH and any of alkyl groups having 1 to 4 carbon atoms, and n is an integer of 1 to 10 respectively. show.

In preparing these halogenated phenol derivatives (A), for example, halogenated phenol compounds such as parachlorophenol, parabromophenol, orthochlorophenol, orthobromophenol can be mentioned as starting materials, and among them, parachlorophenol and para. Bromophenol, especially parachlorophenol, is preferably used.

Halogen by condensing such a raw material with formaldehyde in the presence of an alkaline catalyst, or by reacting a condensate obtained by previously reacting the raw material with an acid catalyst in the presence of an alkaline catalyst. The formaldehyde derivative (A) can be obtained.

Further, the halogenated phenol compound can be co-condensed with formaldehyde in combination with other phenolic compounds. Examples of other phenolic compounds include phenol, resorcin, orthocresol, paracresol, paratalital butylphenol and 2,5-dimethylphenol. Of these, resorcin is particularly preferably used.

Specific examples of the halogenated phenol derivative (A) include 2,6-bis (2', 4'-dihydroxy-phenylmethyl) -4-chlorophenol ("Casabond" manufactured by Thomas One Co., Ltd., Nagase Kasei Kogyo (Nagase Kasei Kogyo). "Denabond" (registered trademark) manufactured by Co., Ltd.), 2,6-bis (2', 4'-dihydroxy-phenylmethyl) -4-bromophenol and 2,6-bis (2', 4'-dichlorophenylmethyl) ) -4-Chlorophenol and the like. Among them, those containing a chlorophenol compound having 3 or more benzene nuclei as a main component are preferably used from the viewpoint of heat resistance and fatigue resistance.

The blocked isocyanate compound (B) used in the present invention is one in which the blocking agent is liberated by heating to generate an active isocyanate compound, and specifically, tolylene diisocyanate, metaphenylenedi isocyanate, diphenylmethane diisocyanate, hexamethi Blocking of polyisocyanate compounds such as lindiisocyanate and triphenylmethane triisocyanate and phenols such as phenol, cresol and resorcin, lactams such as ε-caprolactam and valerolactam, and oximes such as acetoxime, methylethylketooxime and cyclohexaneoxime. Examples include reaction products with agents.

Among these blocked polyisocyanate compounds, aromatic polyisocyanate compounds blocked with ε-caprolactam and aromatic compounds of diphenylmethane diisocyanate give good results.

The adhesive treatment agent for rubber and fiber of the present invention contains at least a halogenated phenol derivative (A) and a blocked isocyanate compound (B), and the weight ratio of (solid content of A): (solid content of B) is 50 :. It is necessary that the content is 50 to 80:20 and the solid content of the halogenated phenol derivative (A) in 100% by weight of the total solid content is 30 to 60% by weight, preferably (A). Solid content): The weight ratio of (solid content of B) is 60:40 to 70:30, and the solid content of the halogenated phenol derivative (A) in 100% by weight of the total solid content is 35 to 55 weight by weight. %. If the weight ratio of (solid content of A): (solid content of B) is less than 50:50, that is, if the amount of the blocked isocyanate compound is large, the cord may become hard and the fatigue resistance may deteriorate, and 80:20. If the amount exceeds, that is, the amount of the blocked isocyanate compound is small, the adhesiveness may deteriorate.

The adhesive treatment agent for rubber and fiber of the present invention contains the halogenated phenol derivative (A) and the blocked isocyanate compound (B) in the same treatment agent, and is blocked from the halogenated phenol derivative (A). It is an essential condition that the isocyanate compound (B) is contained within the range of the above-specified compounding ratio. Adhesion that is contained in the same treatment agent and is within the specified range of the present invention to exhibit excellent adhesion between rubber and fiber and excellent fatigue resistance of fiber in rubber in a high temperature atmosphere. It becomes a treatment agent.

The rubber / fiber adhesive treatment agent of the present invention preferably contains a rubber latex (C). The (C) rubber latex that can be used in the present invention is, for example, natural rubber latex, butadiene rubber latex, styrene / butadiene / rubber latex, vinylpyridine / styrene / butadiene rubber latex, nitrile rubber latex, hydride nitrile rubber latex, and chloroprene rubber. Latex, chlorosulfonated rubber latex, ethylene / propylene / diene rubber latex and the like can be mentioned, and these can be used alone or in combination.

Further, in the adhesive treatment agent for rubber / fiber of the present invention, the halogenated phenol derivative (A), the blocked isocyanate compound (B), and the rubber latex (C) are (solid content of A + solid content of B) :( It is preferable that the weight ratio of (solid content of C) is 80:20 to 60:40. More preferably, the weight ratio of ((solid content of A) + (solid content of B)): (solid content of C) is 75:25 to 65:35. If it is out of this range, the adhesive strength may be insufficient or the fatigue resistance may be deteriorated.

Further, the adhesive treatment agent for rubber / fiber of the present invention may contain resorcin / formalin / rubber latex (RFL). Resorcin-formalin-rubber latex (RFL) is a mixture of resorcin-formaldehyde initial condensate and rubber latex. The resorcin / formalin / rubber latex is particularly preferably prepared using a resorcin / formaldehyde initial condensate obtained by initial condensation under an alkaline catalyst. For example, resorcin and formaldehyde are added and mixed in an alkaline aqueous solution containing an alkaline compound such as sodium hydroxide, allowed to stand at room temperature for several hours, initial condensation of resorcin and formaldehyde, and then a rubber latex is added to the mixed emulsion. It is prepared by the method of.

The resorcin / formaldehyde initial condensate preferably has a molar ratio of resorcin to formaldehyde of 1: 0.3 to 1: 5, preferably 1: 0.75 to 1: 2.0. If the molar ratio of formaldehyde is less than the above range, the dip cord may become sticky and deteriorate the process passability, while if the molar ratio of formaldehyde is more than this range, the adhesive strength may decrease. There is.

Examples of the rubber latex used for preparing resorcin / formarin rubber latex include natural rubber latex, butadiene rubber latex, styrene / butadiene rubber latex, vinylpyridine / styrene / butadiene rubber latex, nitrile rubber latex, and hydride nitrile rubber latex. Examples thereof include chloroprene rubber latex, chlorosulfonated rubber latex, ethylene / propylene / diene rubber latex, and these can be used alone or in combination.

For the resorcin / formalin / rubber latex, it is preferable that the compounding ratio of the resorcin / formaldehyde initial condensate and the rubber latex is 2/1 to 1/12 in terms of solid content weight. If it is out of this range, the adhesive strength may be lowered, or the process passability at the time of manufacturing a rubber product using the synthetic fiber cord for rubber reinforcement obtained in the present invention may be deteriorated.

The rubber / fiber adhesive treatment agent of the present invention preferably does not contain resorcin-formaldehyde resin (D) in 100% by weight of the total solid content. That is, the content of the resorcin-formaldehyde resin (D) is preferably 2.4% by weight or less, more preferably 1.8% by weight or less. When the content of the resorcin-formaldehyde resin (D) exceeds the above range, the process passability at the time of manufacturing a rubber product using the synthetic fiber cord for rubber reinforcement obtained in the present invention and the storage stability of the adhesive treatment agent deteriorate. there is a possibility. As the resorcin-formaldehyde resin (D), the above-mentioned resorcin-formaldehyde initial condensate can be used.

In the adhesive treatment agent for rubber and fiber of the present invention, the liquid viscosity of the adhesive treatment agent that has passed 240 hours at 20 ° C. after adjustment has an increase rate of 5% or less as compared with the liquid viscosity of the adhesive treatment agent immediately after adjustment. preferable. More preferably, the rate of increase is 3% or less. If the rate of increase in liquid viscosity exceeds the above range, the process passability during manufacturing of rubber products using the synthetic fiber cord for rubber reinforcement obtained in the present invention and the storage stability of the adhesive treatment agent may deteriorate. The adjustment means that the components including the halogenated phenol derivative (A) and the blocked isocyanate compound (B), and if necessary, the rubber latex (C) and the resorcin-formaldehyde resin (D) are uniformly mixed.

The method for setting the liquid viscosity of the adhesive treatment agent 240 hours after the adjustment to an increase rate of 5% or less as compared with the liquid viscosity immediately after the adjustment is not particularly limited, but for example, the halogenated phenol derivative (A) and the block in the adhesive treatment agent. This can be achieved by setting the blending amount of the doisocyanate compound (B) and the rubber latex (C) to the above-mentioned preferable range and then setting the content of the resorcin-formaldehyde resin (D) in the adhesive to the above-mentioned preferable range. ..

It is preferable that the adhesive treatment agent for rubber / fiber of the present invention is not substantially aged after mixing all the components to be used. That is, the adjusted aging time is 1 hour or less, more preferably 30 minutes or less. If the aging time exceeds the above range, the process passability at the time of manufacturing a rubber product using the synthetic fiber cord for rubber reinforcement obtained in the present invention may deteriorate. The aging condition is a temperature near room temperature, and the conventional adhesive requires aging for a long time (12 to 24 hours) after mixing all the components, but the adhesive treatment agent for rubber and fiber of the present invention is substantially. Since aging is not required, it has an industrial merit of shortening the process time.

The adhesive treatment agent for rubber / fiber of the present invention has a solid content dissolved or dispersed in water, and the total solid content concentration is preferably 5 to 25% by weight, more preferably 7 to 20% by weight. It is good to do. If it is out of this range, the adhesive strength may be lowered, or the process passability at the time of manufacturing a rubber product using the synthetic fiber cord for rubber reinforcement obtained in the present invention may be deteriorated.

The synthetic fiber cord for rubber reinforcement of the present invention contains at least the above-mentioned adhesive treatment agent for rubber / fiber of the present invention (halogenated phenol derivative (A) and blocked isocyanate compound (B)) in the synthetic fiber ( The weight ratio of (A solid content): (B solid content) is 50:50 to 80:20, and the solid content of the halogenated phenol derivative (A) in 100% by weight of the total solid content is. 30 to 60% by weight) is attached. Further, the adhesive treatment agent preferably contains a rubber latex (C), and the preferable mode of lignin, blocked isocyanate and rubber latex is used in the above-mentioned adhesive treatment agent for rubber and fiber of the present invention. You can use things.

Here, the amount of the adhesive treatment agent for rubber / fiber of the present invention adhered to the synthetic fiber is in the range of 1.0 to 2.9% by weight of the solid content weight of the adhesive treatment agent with respect to 100% by weight of the synthetic fiber. This is preferable from the viewpoint of adhesiveness and fatigue resistance, and more preferably 1.5 to 2.8% by weight. If the amount of adhesion is less than 1.0% by weight, the adhesive strength is lowered, and if it exceeds 2.8% by weight, the process passability at the time of manufacturing a rubber product using the synthetic fiber cord for rubber reinforcement obtained in the present invention is deteriorated. there is a possibility.

The synthetic fiber used in the synthetic fiber cord for rubber reinforcement of the present invention is preferably in the form of a multifilament. Examples of the material constituting the synthetic fiber include nylon 6, nylon 66, nylon 46, polyethylene terephthalate, polyethylene naphthalate, aramid, polyvinyl alcohol, and the like. From the viewpoint of durability and industrial productivity, it is preferable to contain at least one selected from nylon fiber, polyester fiber and aromatic polyamide fiber.

The polyester fiber is preferably a fiber obtained by melt-spinning and drawing a polyester containing terephthalic acid as a main bifunctional carboxylic acid and ethylene glycol as a main glycol component, but partly or all of terephthalic acid is 2,6-. Fibers made of polyester in which naphthalenedicarboxylic acid, 4,4-dicarboxyphenoxyetane, isocyanate group, etc. are replaced, and ethylene glycol is partially or wholly replaced with diethylene glycol, propylene glycol, butanediol, etc. are also used. be able to.

Further, the polyester may be a copolymer of a trifunctional compound such as trimesic acid, trimellitic acid, phosphoric acid, phosphoric acid, glycerin, and trimethylolpropane in a small amount.

Further, the polyester fiber may be modified with various modifiers such as a terminal carboxyl group blocking agent such as a carbodiimide compound, an epoxy compound, an isocyanate compound, and an oxazoline compound.

As the aromatic polyamide fiber, those made of poly-p-phenylene terephthalamide, poly-p-phenylene 3-4'diphenyl ether terephthalamide, and a copolymer mainly composed of these are preferably used.

Further, the synthetic fiber used in the present invention may be previously imparted with a polyepoxide compound in the silk reeling process. Examples of the polyepoxide compound include compounds containing at least two or more epoxy groups in one molecule in an amount of 0.1 g or more per 100 g of the compound. Specifically, it is unsaturated with a reaction product of polyhydric alcohols such as pentaerythritol, ethylene glycol, polyethylene glycol, propylene glycol, glycerol and sorbitol with halogen-containing epoxides such as epichlorohydrin, peroxidation or hydrogen peroxide. Polyepoxide compounds obtained by oxidizing compounds, such as 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexenecarboxylate, bis (3,4-epoxy-6-methyl-cyclohexylmethyl) adipate, phenol novolac type, Examples thereof include aromatic polyepoxides such as hydroquinone type, biphenyl type, bisphenol S type, brominated novolak type, xylene-modified novolak type, phenol glioxal type, trisoxyphenylmethane type, trisphenol PA type, and bisphenol type polyepoxides. Particularly preferred are sorbitol glycidyl ether type and cresol novolak type polyepoxides.

These compounds are usually used as emulsions and solutions. That is, the above compound is dissolved in a solvent and used as a solution, or emulsified with a usual emulsifier such as sodium alkylbenzene sulfonic acid, sodium dioctyl sulfosuccinate salt, nonylphenol ethylene oxide adduct and the like, and used as an emulsifying solution.

The polyepoxide compound is applied together with a spinning oil in the process of producing synthetic fibers. The adhered amount of the polyepoxide compound at this time is preferably in the range of 0.1 to 5% by weight. When the amount of the polyepoxide compound adhered is within the above range, the effect of the polyepoxide compound is sufficiently exhibited, and a satisfactory adhesiveness between the synthetic fiber and the rubber can be obtained. Further, within the above range, the fibers do not become too hard, and the strength is unlikely to decrease in the plying process described later.

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

From the viewpoint of improving fatigue resistance, the synthetic fiber cord for rubber reinforcement of the present invention is made by twisting the synthetic fiber into a twisted cord, and the twisted cord is woven as it is or in a threaded shape, and then the adhesive treatment agent of the present invention is used. It can be obtained by dipping and heat treatment. For example, a twisted cord used for a carcass tire cord is twisted in the S or Z direction, then two or three lower twisted cords are combined and usually the same number of upper twists are applied in the opposite direction to the lower twist. You can use the code. The twisted cord is used as a warp, a cotton thread is covered with a weft, or a cotton thread is covered with an organic fiber to form a weft, and the bamboo blind is woven into a bamboo blind to form a bamboo blind. Heat treatment is performed to obtain a dip fabric.

On the other hand, in the case of cords for hoses and belts, for example, a single-twisted twisted cord is produced by under-twisting, and two or three cords are combined and usually the same number of up-twists are applied in the direction opposite to the under-twist. A twisted plying cord is produced, and the dip heat treatment is performed with an adhesive treatment agent in the form of these single-twisted or multi-twisted plying cords to obtain a dip cord.

The synthetic fiber cord for rubber reinforcement to which the adhesive treatment agent of the present invention is adhered refers to both the dip counter and the dip cord.

The synthetic fiber cord for rubber reinforcement of the present invention is an epoxy compound before dipping and heat-treating the twisted yarn cord with an adhesive treatment agent for rubber / fiber containing at least a halogenated phenol derivative (A) and a blocked isocyanate compound (B). The primer treatment agent may be subjected to dip treatment and heat treatment with a primer treatment agent containing the above to adhere the primer treatment agent to the synthetic fiber.

The synthetic fiber cord for rubber reinforcement of the present invention characterized by the above is significantly improved in fatigue resistance during the rubber vulcanization process and the use of rubber products. The rubber product reinforced with the synthetic fiber cord for rubber reinforcement according to the present invention is extremely useful for rubber reinforcement because it can withstand harsh use for a longer period of time than before when used as a tire, belt and hose. ..

Next, a method for manufacturing the synthetic fiber cord for rubber reinforcement of the present invention will be described.

As an example of the method for producing the synthetic fiber cord for rubber reinforcement of the present invention, the twisted yarn cord of the synthetic fiber is dipped in the adhesive treatment agent for fiber / rubber of the present invention, and subsequently, moisture is added at a temperature of preferably 100 to 150 ° C. It is a method of drying and then applying a heat treatment at 200 to 255 ° C.

Here, the dip means to apply the adhesive treatment agent to the twisted yarn cord by running the twisted yarn cord in a dip tank in which a roller is installed inside and the adhesive treatment agent is filled. The heat treatment refers to heating the plying cord by running the plying cord in an oven in which a roller is installed and the temperature can be set to a predetermined temperature. As a dip processing machine that performs such a dip and heat treatment, for example, it is commercially available from Ritzler. As another method for adhering the adhesive treatment agent to the synthetic fiber, any method such as application by spraying the adhesive treatment agent from a nozzle can be adopted.

Further, in order to control the amount of the solid content adhered to the synthetic fiber, means such as squeezing with a pressure welding roller, scraping with a scraper, blowing off with air blowing, and suction may be used.

Further, after the above-mentioned drying and heat treatment, the synthetic fiber cord can be slidably contacted with the edge to perform a softening treatment for obtaining an arbitrary cord bending hardness.

Further, when the adhesive treatment agent containing RFL is further attached following the above, the same dipping method as the above method can be adopted. That is, the synthetic fiber cord for rubber reinforcement obtained above is dipped in an adhesive treatment agent containing RFL, the moisture is preferably dried at a temperature of 100 to 150 ° C., and then heat treatment is performed at 200 to 255 ° C. The same method as described above can be adopted for controlling the amount of solid content attached and for the softening treatment.

The synthetic fiber cord for rubber reinforcement of the present invention thus obtained has significantly improved heat-resistant adhesiveness and fatigue resistance when exposed to high temperatures for a long time during a rubber vulcanization process or use of a rubber product. The rubber product reinforced with the synthetic fiber cord for rubber reinforcement according to the present invention is extremely useful for rubber reinforcement because it can withstand harsh use for a longer period of time than before when used as a tire, belt and hose. ..

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples. In the examples specifically described below, each measured value was obtained by the following method.

(1) Adhesive treatment amount The weight of the twisted cord per fixed length is measured in advance, and the weight of the synthetic fiber cord of the same length after the adhesive is attached is measured to determine the amount of adhesion as a difference. Calculated.

(2) Liquid viscosity change rate of adhesive treatment agent 30 mL of adhesive treatment agent immediately after adjustment was taken in a sample container, and a sound fork vibration type (SV type) viscometer (manufactured by A & D Co., Ltd., (trade name) SV- Using 10H), the initial liquid viscosity was evaluated by measurement according to JIS Z-8803. Subsequently, the measured adhesive was sealed in a closed container, stored at 20 ° C. for 240 hours, and treated over time, and the liquid viscosity of the adhesive after the time-treated treatment was evaluated by the same method as described above. The change in liquid viscosity after aging treatment compared to the initial liquid viscosity was determined as a percentage and used as the liquid viscosity change rate of the adhesive treatment agent.

(3) T-Initial Adhesive Strength and T-Heat-Resistant Adhesive Strength The adhesive strength between the synthetic fiber cord and rubber is shown. In accordance with JIS L-1017 (2002) Annex 1 3.1T test (method A), the synthetic fiber cord is embedded in unvulcanized rubber, and the initial adhesive strength under pressure is 150 ° C, 30 minutes, heat resistance. The adhesive force was press vulcanized at 170 ° C. for 70 minutes, and after allowing to cool, the synthetic fiber cord was pulled out from the rubber block at a rate of 300 mm / min, and the load required for the pulling out was displayed in N / cm. The average value of 10 measurements was taken as the adhesive strength value.

(4) Fatigue resistance in rubber (retention rate)
The evaluation was made in accordance with 2.2.2 Disc Fatigue Strength (Goodrich Method) of Annex 1 of JIS L-1017 (2002). Two synthetic fiber cords are embedded in unvulcanized rubber and vulcanized at 150 ° C. for 30 minutes to prepare a rubber composite. This test piece was deformed with a compression of 6.3% and an extension of 12.6% as one cycle at 2600 cycles / minute under an atmosphere of 100 ° C. for 12 hours, and then the synthetic fiber cord was taken out from the rubber and fractured after fatigue. The strength is measured and expressed by the retention rate before and after the fatigue test. The average value of 8 measurements was taken as the retention rate value.

The composition of the unvulcanized rubber compound used for measuring the T-initial adhesive strength, the T-heat resistant adhesive strength, and the fatigue resistance in rubber is as follows.
Natural rubber (RSS # 1): 70 (part by weight)
SBR (JSR1501): 30 (part by weight)
RF carbon black: 40 (weight part)
Stearic acid: 2 (part by weight)
Sulfur: 2 (part by weight)
Zinc oxide: 5 (part by weight)
2,2'-Dithiobenzothiazole: 3 (part by weight)
Naphthenic acid process oil: 3 (part by weight).

(5) Process passability The fiber cord was run 1000 m on a friction tester (model number: YF850) manufactured by Toray Engineering Co., Ltd. shown in FIG. 1, and the state of adhesion of residue to the guides was used as an index. The fiber cord is taken out from the fiber cord sample 1 for measurement, is subjected to a load 3 via a nip roller 2 for thread feeding, and is partially wound around the surface of a satin-finished chrome-plated tube 4 to travel. Further, the fiber cord is wound through the nip roller 5 for thread feeding. At that time, the amount of adhesion to the nip roller 2 and the nip roller 5 for thread feeding was measured. Those with extremely little residue are indicated as A, those with a small amount of residue are indicated as B, and those with a large amount of residue are indicated as C.

(Example 1)
Resorcin (R) is added to the caustic soda aqueous solution and sufficiently stirred and dispersed, and formalin (F) is added thereto so that the R / F ratio is 1 / 1.4 (molar ratio) and mixed uniformly. The mixture was aged at a temperature of 25 ° C. for 2 hours to obtain a resorcin-formalin initial condensate (resorcin-formaldehyde resin (D)) dispersion having a solid content concentration of 10%. Subsequently, in 15 g of this resorcin formarin initial condensate dispersion, 337 g of "Denabond E" (manufactured by Nagase Kasei Kogyo Co., Ltd., solid content concentration 20%) as a halogenated phenol derivative (A), and a blocked isocyanate compound. 121 g of "Elastron" BN27 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., solid content concentration 30%) as (B), and "Nippor 2518FS" (manufactured by Nippon Zeon Co., Ltd., solid content concentration 30%) as rubber latex (C). 149 g and 378 g of water were added, mixed uniformly, and aged at a temperature of 25 ° C. for 15 minutes to obtain an adhesive treatment agent having a solid content concentration of 15%.

One 1670 dtex polyester multifilament yarn (“Tetron” 1670T-288-707C manufactured by Toray Industries, Inc.) was twisted 12 times / 10 cm to obtain a twisted yarn cord.

The plying cord was immersed in the adhesive treatment agent obtained above using a computer processor (manufactured by Ritzler Co., Ltd.), dried at 120 ° C. for 2 minutes, and then heat-treated at 245 ° C. for 1 minute. A synthetic fiber cord was obtained. The adhesive solid content adhered amount of the obtained synthetic fiber cord was 2.1% by weight with respect to 100% by weight of the synthetic fiber.

The synthetic fiber cord thus obtained was embedded in unvulcanized rubber and vulcanized, and then T-initial adhesive strength, T-heat resistant adhesive strength, and fatigue resistance in rubber were measured. The results are shown in Table 1.

(Examples 2 to 10, Comparative Examples 1 to 12)
In Example 1, the blending amount of the halogenated phenol derivative (A), the blocked isocyanate compound (B), and the rubber latex (C) in the adhesive, the content of the resorcin-formalin initial condensate, and the liquid viscosity of the adhesive treatment agent. The treatment was carried out under the same conditions as in Example 1 except that the aging time after adjusting the adhesive treatment agent and the adhesion amount of the adhesive treatment agent were changed as shown in Tables 1 and 2, and the evaluation was carried out in the same manner. The evaluation results are also shown in Tables 1 and 2.

As shown in the results of Tables 1 and 2, in the cases of Examples 1 to 10 according to the present invention, the adhesiveness to rubber, the heat-resistant adhesiveness, and the fatigue resistance in a high temperature atmosphere are good, and further, in the present invention. It can be seen that the process passability at the time of manufacturing a rubber product using the obtained synthetic fiber cord for reinforcing rubber and the storage stability of the adhesive treatment agent are improved.

Claims (10)

It contains at least the halogenated phenol derivative (A) and the blocked isocyanate compound (B), and the weight ratio of (solid content of A): (solid content of B) is 50:50 to 80:20, and is total solid. An adhesive treatment agent for rubber / fiber, wherein the content of the solid content of the halogenated phenol derivative (A) in 100% by weight is 30 to 60% by weight. The first aspect of the present invention, further comprising a rubber latex (C), wherein the weight ratio of (solid content of A + solid content of B): (weight of solid content of C) is 80:20 to 60:40. Adhesive treatment agent for rubber and fibers. The invention according to claim 1 or 2, further comprising a resorcin-formaldehyde resin (D), wherein the content of the resorcin-formaldehyde resin (D) in 100% by weight of the total solid content is 2.4% by weight or less. Adhesive treatment agent for rubber and fiber. The rubber according to any one of claims 1 to 3, wherein the liquid viscosity of the adhesive treatment agent 240 hours after the adjustment is 5% or less as compared with the liquid viscosity of the adhesive treatment agent immediately after the adjustment. -Adhesive treatment agent for fibers. The method for producing an adhesive treatment agent for rubber / fiber according to any one of claims 1 to 4, wherein the aging time after adjustment is 1 hour or less. Production method. A synthetic fiber cord for rubber reinforcement, which comprises a synthetic fiber to which the adhesive treatment agent for rubber / fiber according to any one of claims 1 to 4 is attached. The synthetic fiber cord for rubber reinforcement according to claim 6, further comprising an adhesive treatment agent containing resorcin, formalin, and rubber latex (RFL) attached. The synthetic fiber cord for rubber reinforcement according to claim 6 or 7, wherein the amount of solid content adhered to the adhesive treatment agent for rubber / fiber is 1 to 2.9% by weight with respect to the synthetic fiber. The synthetic fiber cord for rubber reinforcement according to any one of claims 6 to 8, wherein the synthetic fiber contains at least one selected from nylon fiber, polyester fiber, and aromatic polyamide fiber. A rubber product containing the synthetic fiber cord for rubber reinforcement according to any one of claims 6 to 9.

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