JP4983298B2 - Polyester fiber cord for hose reinforcement - Google Patents

Description

  The present invention relates to a polyester fiber cord for reinforcing a hose. Specifically, the adhesiveness with the ethylene / α-olefin / non-conjugated diene copolymer rubber compound (hereinafter referred to as “EPDM rubber”) is good, and the process passability at the time of manufacturing the hose, that is, polyester. The present invention relates to a polyester fiber cord for reinforcing a hose in which the drop of RFL on the surface of the fiber cord is improved.

  Conventionally, polyester fibers represented by polyethylene terephthalate fibers have physical properties such as high strength and modulus, low elongation and creep, and excellent fatigue resistance. Conventionally used as a fiber. However, since the surface of the polyester fiber itself is inactive, there is a problem of poor adhesion to rubber. In recent years, in the hose field used for automobile brake hoses, EPDM rubbers having excellent high temperature characteristics are mainly used. However, these rubbers have few double bonds in their chemical structures and are poor in reactivity. Has the problem. For this reason, various methods for improving the adhesion between the polyester fiber cord and the EPDM rubber have been studied.

  On the other hand, when a plurality of fiber cords that have been subjected to adhesive treatment are aligned and braided into a hose shape, when the cord that has undergone adhesive treatment rubs against the guides, the adhesive drops and adheres to the guides. There is also a problem that scattering occurs and the productivity and working environment are impaired.

  Furthermore, when the fiber cord is used for reinforcement of a brake hose or the like, it is required to be a flexible fiber cord from the viewpoint of fatigue resistance, workability when the hose is attached, vibration absorption, and the like.

As an attempt to solve the above problem, Patent Document 1 discloses a technique of treating with an adhesive in which resorcin / formalin / rubber latex and a phenol compound are mixed in a certain range. Patent Document 2 discloses a technique in which a polyester fiber pre-applied with a polyepoxide compound is treated with a second treating agent containing resorcin / formalin / rubber latex and a chlorophenol compound. Further, Patent Document 3 discloses a technique in which polyester fiber is treated with a first treatment agent containing a polyepoxide compound and then treated with a second treatment agent containing a specific composition of resorcin / formalin / rubber latex and a chlorophenol compound. ing. Patent Document 4 discloses a technique of treating polyester fibers previously treated with a treatment agent containing a polyepoxide compound with a treatment agent containing resorcin / formalin / rubber latex containing polybutadiene rubber latex as an essential component. However, even with these methods, it has not been possible to obtain a polyester fiber cord for reinforcing a hose that simultaneously satisfies adhesiveness with EPDM rubber, good processability in the manufacturing process, and flexibility.
JP 58-19375 (Claims) JP-A-7-331583 (Claims) Japanese Patent Laid-Open No. 11-286875 (Claims) JP-A-11-286876 (Claims)

  In view of the background of such prior art, the present invention has good adhesiveness with an ethylene / α-olefin / non-conjugated diene copolymer rubber compound (EPDM rubber) and has processability during hose production. The present invention intends to provide a polyester fiber cord for reinforcing a hose that improves (dropping off the RFL of the polyester fiber cord surface) and is flexible.

The present invention employs the following means in order to solve such problems. That is, the present invention is a polyester fiber cord for reinforcing a hose obtained by adding a treatment agent containing resorcin / formalin / rubber latex (RFL) and chloro-modified resorcin (P) to a polyester fiber previously provided with a polyepoxide compound. In addition, the hose reinforcing polyester fiber cord is characterized in that the treating agent satisfies all the following requirements.
(A) R / F = 1 / 0.5 to 1/3 (molar ratio)
(B) RF / L = 1/3 to 1/15 (weight ratio)
(C) P / RFL = 1/1 to 1/5 (weight ratio).
(D) RF ripening time: 4-8 hours
The rubber latex includes an ethylenically unsaturated acid-modified vinylpyridine / styrene / butadiene rubber latex (modified VP) and a polybutadiene rubber latex (PB), and a modified VP / PB = 90/10 to 50/50. (Dry weight ratio).
(Wherein, R resorcinol weight, F is the amount of formalin, L is the amount of rubber latex, P is chloro modified resorcin amount, RF is resorcinol-formaldehyde in, RFL represents resorcin-formalin-rubber latex amount. Further, in the formula The modified VP represents the amount of ethylenically unsaturated acid-modified vinylpyridine / styrene / butadiene rubber latex, and PB represents the amount of polybutadiene rubber latex.

In addition, in the polyester fiber cord for hose reinforcement of the present invention, the following (1) to ( 2 ) are preferable conditions, and further excellent effects can be expected by application of these conditions.
( 1 ) Gurley bending stiffness is 500 to 2000 mg.
( 2 ) The hose reinforcing polyester fiber cord is for automobile brake hoses.
That is, the present invention is an EPDM system that could not be achieved in a conventional hose-reinforced polyester fiber cord by controlling the adhesive component within a certain range and setting the aging time of the RFL to a relatively long time. This makes it possible to simultaneously satisfy all the properties of adhesion to rubber, good processability in the production process, and flexibility.

  That is, the present invention is an EPDM system that could not be achieved in a conventional hose-reinforced polyester fiber cord by controlling the adhesive component within a certain range and setting the aging time of the RFL to a relatively long time. This makes it possible to simultaneously satisfy all the properties of adhesion to rubber, good processability in the production process, and flexibility.

  According to the present invention, the adhesiveness with the ethylene / α-olefin / non-conjugated diene copolymer rubber compound (EPDM rubber) is good, and the process passability during the production of the hose (the surface of the polyester fiber cord) It is possible to provide a polyester fiber cord for reinforcing a hose with improved RFL dropout.

  The polyester fiber cord for reinforcing a hose of the present invention (hereinafter referred to as a cord) is an excellent result with an EPDM rubber as a result of intensive studies to create an industrially practical cord for use in automobile hoses, particularly automobile brake hoses. As a result, a polyester fiber cord for reinforcing a hose having excellent adhesiveness, good process passability in which the RFL adhesive is not dropped from the cord at the time of manufacturing the hose, and flexibility that is advantageous for hose molding has been obtained.

  Hereinafter, the present invention will be described in detail.

  The polyester fiber used in the present invention refers to a polyester composed of dicarboxylic acid and glycol having ethylene terephthalate as the main repeating unit. Examples of the dicarboxylic acid component include terephthalic acid, 2,6-naphthalenedicarboxylic acid, isophthalic acid, 1,4-cyclohexanedicarboxylic acid, and the like. Examples of the glycol component include ethylene glycol, propylene glycol, tetramethylene glycol, 1,4-cyclohexanedimethanol and the like. A part of the dicarboxylic acid component may be replaced with adipic acid, sebacic acid, dimer acid, sulfonic acid metal-substituted isophthalic acid, etc., and a part of the glycol component may be diethylene glycol, neopentyl glycol, 1, It may be replaced with 4-cyclohexanediol, 1,4-cyclohexanedimethanol, polyalkylene glycol, or the like. Among these, polyethylene terephthalate in which 90 mol% or more of the dicarboxylic acid component is made of terephthalic acid and 90 mol% or more of the glycol component is made of ethylene glycol is preferable. This polyester includes various inorganic particles such as titanium oxide, silicon oxide, calcium carbonate, silicon nitride, clay, talc, kaolin, and zirconium acid, and particles such as crosslinked polymer particles and various metal particles. Antioxidants, sequestering agents, ion exchangers, anti-coloring agents, waxes, silicone oils, various surfactants and the like may be added.

  Moreover, when using as a brake hose, the thing whose intrinsic viscosity of a fiber is 0.85 or more is preferable. When the intrinsic viscosity of the fiber is 0.85 or more, sufficient strength for hose reinforcement can be obtained, and a practical level of hose burst pressure can be expressed. Further, the polyester fiber has a maximum value of the main dispersion appearing in the temperature dispersion of the loss tangent (tan δ) measured at a frequency of 11 Hz using a dynamic viscoelasticity measuring apparatus is 130 ° C. or higher, more preferably 140 ° C. or higher. Is preferred. When the main dispersion of the loss tangent (tan δ) is in the above range, even when the brake fluid touches the fiber, the diffusion of the brake fluid rust preventive agent into the polyester is suppressed, and deterioration Fewer hoses can be obtained.

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

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

  The polyepoxide compound used in the present invention is usually applied together with a spinning oil agent in a process for producing polyester fibers. In this case, the amount of the polyepoxide compound attached is usually preferably in the range of 0.1 to 5 parts by weight with respect to 100 parts by weight of the polyester fiber. When the adhesion amount of the polyepoxide compound is less than 0.1 parts by weight, the effect of the polyepoxide compound is not sufficiently exhibited, and there is a possibility that satisfactory adhesiveness cannot be obtained between the polyester fiber and the ethylene propylene rubber. On the other hand, when the adhesion amount of the polyepoxide compound exceeds 5 parts by weight, the fiber becomes very hard and not only difficult to impart in the yarn making process, but also the permeability of the treatment agent to be treated in the next process and after. As a result of the decrease, the adhesive performance may decrease, which is not preferable.

  The cord of the present invention is obtained by applying a treatment agent containing resorcin / formalin / rubber latex and chloro-modified resorcin to a polyester fiber to which a polyepoxide compound has been applied in advance.

  Here, the resorcin / formalin / rubber latex is a mixture of an initial condensate of resorcin / formaldehyde and a rubber latex. The resorcin / formaldehyde initial condensate is obtained by condensing resorcin and formaldehyde in the presence of an alkali catalyst or an acid catalyst, and the molar ratio of resorcin (R) to formaldehyde (F) is 1 / 0.5 to It is necessary to be 1/3. Preferably, the range is 1/1 to 1/3. When the molar ratio of R / F is out of the range of 1 / 0.5 to 1/3, the adhesiveness decreases or the process passability deteriorates.

  Furthermore, as the resorcin / formaldehyde initial condensate, a novolak type resin obtained by reacting dihydroxybenzene and formaldehyde in advance in the absence of a catalyst or an acidic catalyst can also be used. Specifically, for example, a compound condensed with 0.7 mol or less of formaldehyde with respect to 1 mol of resorcin (for example, trade name “SUMIKANOL 700” registered trademark, manufactured by Sumitomo Chemical Co., Ltd.). When using a novolak-type condensate of resorcin and formaldehyde, it is preferable to add formaldehyde after dissolution in an aqueous alkali catalyst dispersion to adjust the molar ratio of resorcin to formaldehyde to 1/1 to 1/3. The alkali catalyst used here is an alkali metal hydroxide, preferably sodium hydroxide. The concentration of the alkaline catalyst aqueous dispersion may be about 1 to 10 molar.

The rubber latex used in resorcin / formalin / rubber latex is natural rubber latex, butadiene rubber latex, styrene / butadiene rubber latex, ethylenically unsaturated acid-modified styrene / butadiene rubber latex, vinylpyridine / styrene / butadiene rubber latex, Examples include ethylenically unsaturated acid-modified vinylpyridine / styrene / butadiene rubber latex, acrylonitrile / butadiene rubber latex, chloroprene rubber latex, chlorosulfonated polyethylene, and ethylene / propylene / non-conjugated diene terpolymer rubber latex. , can be used as a mixture thereof, in the present invention, the ethylenically unsaturated acid-modified vinyl pyridine-styrene-butadiene latex (modified VP), To mandatory to include re-butadiene rubber latex (PB) at a rate of modified VP / PB = 90 / 10~50 / 50 ( dry weight). From the viewpoint of heat resistance and adhesiveness, it is preferable that the ethylenically unsaturated acid-modified vinylpyridine / styrene / butadiene terpolymer rubber latex accounts for 50% by weight or more out of 100% by weight of the rubber latex.

  Examples of the ethylenically unsaturated acid used herein include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, itaconic acid, fumaric acid, maleic acid, and butenetricarboxylic acid, itaconic acid monoethyl ester, Monoalkyl ester of unsaturated dicarboxylic acid such as monobutyl ester of fumaric acid, maleic acid monobutyl ester, unsaturated sulfonic acid such as sulfoethyl sodium acrylate, sulfopropyl sodium methacrylate, acrylamide propane sulfonic acid or its alkali salt These can be used, and these can be used alone or in combination of two or more.

  In addition, you may introduce | transduce into a rubber latex by hydrolyzing a carboxyl group after copolymerizing an ethylenically unsaturated ester monomer or an ethylenically unsaturated acid anhydride monomer. In this case, the ethylenically unsaturated acid ester monomer and the ethylenically unsaturated acid anhydride monomer include acrylic acid, methacrylic acid, crotonic acid, cinnamic acid, itaconic acid, fumaric acid, maleic acid, butenetricarboxylic acid. Illustrative are mono-, di- and triesters of unsaturated carboxylic acids such as acids, maleic anhydride and the like, and one or more of these are used.

  In the case where the rubber to be adhered is an ethylene / propylene / diene terpolymer rubber (EPDM rubber) preferably used for a brake hose, an ethylenically unsaturated acid-modified vinylpyridine / styrene / butadiene rubber latex ( Modified VP) and a mixed rubber latex containing polybutadiene rubber latex (PB) are preferably used, and the mixing ratio of the rubber latex is more preferably VP / PB = 90/10 to 50/50 in terms of solid content dry weight ratio. Is preferably 80/20 to 60/40. When the modified VP / PB ratio is larger than 90/10, the process passability may be deteriorated, and when the modified VP / PB ratio is smaller than 50/50, the adhesiveness may be deteriorated.

  Further, the mixing ratio of resorcin / formalin / rubber latex resorcin / formalin and rubber latex is required to be RF / L = 1/3 to 1/15 in terms of solid content weight, and preferably 1/5 to 1/5. It should be 1/12, more preferably 1/7 to 1/10. When the RF / L ratio is out of this range, the adhesiveness may be lowered or the process passability may be deteriorated.

  The chloro-modified resorcin used in the present invention is a compound obtained by condensing parachlorophenol, formalin and resorcin, and is a compound represented by the following general formula.

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

  The method for preparing these chloro-modified resorcins is not particularly limited, and examples thereof include parachlorophenol, orthochlorophenol, parabromophenol, paraiodophenol, orthocresol, paracresol, para-tertiary butylphenol and 2,5-dimethylphenol. Of these, parachlorophenol, parabromophenol, paracresol, and paratertiary butylphenol are used, and parachlorophenol is particularly preferably used.

  By condensing such a starting material with formaldehyde in the presence of an alkali catalyst, or by reacting a condensate obtained by previously reacting the starting material in the presence of an acid catalyst with formaldehyde in the presence of an alkali catalyst. Chloro-modified resorcinol can be obtained.

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

  The compounding ratio of the chloro-modified resorcinol (P) and the resorcin / formalin / rubber latex (RFL) represented by the above formula is required to be P / RFL = 1/1 to 1/5 in terms of solid content. Yes, preferably P / RFL = 1/2 to 1/4. When P / RFL is larger than 1/1, the cord becomes hard, and when P / RFL is smaller than 1/5, the adhesiveness is lowered.

  In the treatment agent used in the present invention, the aging conditions of resorcin (R) and formalin (F) are required to be aged for 4 to 8 hours, and preferably 5 to 7 hours. If the aging time is less than 4 hours, the process passability may deteriorate, and if it exceeds 8 hours, the viscosity of the RF solution is improved, and it becomes difficult to uniformly apply the RFL adhesive to the polyester fiber. There is. The aging temperature is preferably 20 to 25 ° C.

  Further, the ripening condition of RFL is preferably 14 to 30 hours, more preferably 16 to 24 hours under the condition of 20 to 25 ° C. If it is out of this range, the adhesiveness may decrease.

  The total solid concentration of the treatment agent used in the present invention is preferably 5 to 20% by weight, more preferably 7 to 15% by weight. If it is this range, a processing agent is excellent in stability and it can apply | coat an RFL processing agent uniformly to a polyester fiber.

  In order to adhere the treatment agent used in the present invention to the polyester fiber, any method such as dipping, nozzle spraying, coating with a roller or the like can be employed.

  The amount of the treatment agent attached to the polyester fiber is preferably in the range of 0.5 to 4.0 parts by weight, particularly 1.5 to 3.0 parts by weight, with respect to 100 parts by weight of the polyester fiber. Thereby, the adhesiveness with rubber and the process passability are improved.

  The heat treatment after applying the treatment agent to the polyester fiber is dried at 80 to 180 ° C. for 0.5 to 5 minutes, more preferably 1 to 3 minutes, and then 150 to 260 ° C., more preferably 220 to 250 ° C. Heat treatment is preferably performed at a temperature of 0.5 to 5.0 minutes, more preferably 1 to 3 minutes. If the heat treatment temperature is too low, the adhesion with the adherend rubber becomes insufficient. On the other hand, if the heat treatment temperature is too high, the polyester fibers are melted, fused, hardened, and further deteriorated in strength. Disappear.

Further, the number of twists of the cord is preferably such that the twist coefficient defined by the following formula is in the range of 200 to 800.
Twisting coefficient = {twisting number (t / 10 cm) × (denier) ^1/2 }.

The cord thus treated preferably has a Gurley bending stiffness according to JISL10 96 ( 1990 ) of 500 to 2000 mg. When it is less than 500 mg, fatigue resistance may be deteriorated when used in applications where repeated bending stress is applied, such as a brake hose. If it exceeds 2000 mg, it will not be flexible enough to absorb the inherent vibration generated in the brake hose, etc., and vibration damping as a hose used for automobile parts may not be obtained.

  The polyester fiber cord for reinforcing a hose of the present invention can be used as a reinforcing cord for various hoses such as a brake hose, an air conditioner hose, and a fuel hose. It is particularly suitable for a brake hose and can be used as an upper thread or a lower thread.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

  In the present invention, the cord shape / characteristic requirements of the rubber reinforcing cord, the physical property measurement method, and the evaluation method are as follows.

<Evaluation method of rubber reinforcing cord>
(1) Peeling adhesive strength The cord was wound around an aluminum plate so that there was no gap, and EPDM rubber having the composition shown in Table 1 was attached to both sides of the aluminum plate, and press vulcanized at 150 ° C. for 30 minutes. At this time, the thickness of the rubber was 3 mm, and the press pressure was adjusted so that the surface pressure of the rubber and the fiber cord was 30 kgf / cm ² . The size of the aluminum plate and the area around which the fiber cord is wound may be arbitrary. After standing to cool, the peeling force when peeling the fiber cord from the rubber is displayed in N / inch while keeping the rubber and the fiber cord at an angle of 90 ° at a speed of 50 mm / min in an environment of 20 ° C. did. The rubber coverage (%) was obtained by observing the cord peeled off from the rubber with the naked eye during the above peeling test, and expressing the area where the rubber remained on the surface of the cord that was in contact with the rubber as a percentage. .

(2) Amount of treating agent JIS L1017 (2002) 8.15 Dip pickup b) Determined by mass method.

(3) Process passability The code was run on a friction tester manufactured by Toray Engineering Co., Ltd. shown in FIG. 1, and the adhesion state of the RFL residue to the guides was used as an index. A fiber cord is taken out from a fiber cord sample 1 for measurement, passed through a nip roller 2 for feeding a yarn, applied with a yarn load 3, and partially wound around the surface of a satin chrome-plated tube 4, and then a nip for feeding the yarn. It wound up through the roller 5, and measured the RFL adhesion amount to the nip rollers 2 and 5 in that case. An extremely small amount of debris generation was indicated as ◎, a small amount of debris was indicated as ◯, a large amount of debris was indicated as ×, and any case where it was difficult to determine was indicated as Δ.

(4) Gurley Bending Flexibility Using a “Gurley-type flexibility tester” manufactured by Yasuda Seiki Co., Ltd.
Measurement was performed according to the method described in JIS L1096 (1990) 6.20.1A method (Gurley method), and the Gurley bending stiffness was calculated using the following formula. The number of bendings was one reciprocation.
S (Gurley bending stiffness (mg)) = R × (W ₁ × 1 + W ₂ × 2 + W ₄ × 4) × L / W × 3.96
W ₁ , W ₂ , W ₄ = Load (g) and mounting position, R = Scale reading, L = Cord length−0.5 (inch), W = Thread width (inch).

(5) Hose fatigue resistance At 100 ° C., a test of repeated bending was performed while applying a pressure of 100 kgf / cm ² , and the number of repeated bendings when the hose was ruptured was measured.

Example 1
A resorcin / formalin initial condensate: “SUMIKANOL S700” (manufactured by Sumitomo Chemical Co., Ltd., 65% aqueous solution) is added to an aqueous caustic soda solution and sufficiently stirred and dispersed. To this, formalin was added so as to have an R / F ratio of 1/2 (molar ratio), mixed uniformly, and aged at 25 ° C. for 6 hours. Next, “PYRATEX-LB” (manufactured by Nippon A & L Co., Ltd., ethylenically unsaturated acid-modified vinylpyridine / styrene / butadiene rubber latex) and “Nippol LX-111A” (manufactured by Nippon Zeon Co., Ltd., polybutadiene rubber latex) (Ethylenically unsaturated acid-modified vinylpyridine / styrene / butadiene rubber latex / polybutadiene rubber latex = 75/25 (dry weight ratio)) is mixed with the resorcin / formalin initial condensate dispersion and the solid content ratio (RF / L ratio) at a ratio of 1/9 and aged at 25 ° C. for 24 hours. Furthermore, “Denabond E” (manufactured by Nagase Kasei Kogyo Co., Ltd., 20% solution of chloro-modified resorcinol compound) was added so that the RFL and the solid content ratio (“Denabond” / RFL) would be 1/3, and stirred sufficiently Aged at 25 ° C. for 20 hours. The final treatment solution concentration was 13%.

  On the other hand, in the yarn production process, one multifilament of polyester fiber ("T707C" (1670T), manufactured by Toray Industries, Inc.) pre-applied with a polyepoxide compound was subjected to a single twist of 10 t / 10 cm to obtain a twisted cord.

The cord was immersed in the treatment agent using a compute treater (CA Ritzler Co., Ltd., tire cord processor), dried at 120 ° C. for 2 minutes, and then heat treated at 240 ° C. for 1 minute. . The cord had a solid content of 3.1 parts by weight based on 100 parts by weight of the polyester fiber to which the polyepoxide compound had been applied in advance. The cords thus obtained were subjected to a cord peeling force test, a Gurley bending stiffness test, and a process passability test as described above. The results are shown in Table 2.

  The treatment cord thus obtained was bladed at a crossing angle of 108 degrees, molded into a hose using an ethylene propylene-based unvulcanized rubber having the composition shown in Table 1, and steamed at a temperature of 150 ° C. for 40 minutes. Vulcanization was performed. Table 2 also shows the results of the fatigue resistance test performed on this hose.

(Example 2 and Comparative Examples 1 to 10 )
In Example 1, it processed on the conditions similar to Example 1 except having changed the adjustment conditions into the conditions shown in Table 2, and evaluated similarly. The evaluation results are also shown in Table 2.

  As can be seen from the evaluation results shown in Table 2, it can be seen that the polyester fiber cord for reinforcing a hose according to the present invention is excellent in adhesiveness with EPDM rubber, has good process passability, and provides a flexible cord. .

Schematic diagram showing a friction tester that evaluates the processability of fiber cords

Explanation of symbols

1: Fiber cord sample for measurement 2: Nip roller for yarn feeding 3: Load 4: Satin chrome plated tube 5: Nip roller for yarn feeding

Claims (3)

A polyester fiber cord for reinforcing a hose obtained by applying a treatment agent containing resorcin, formalin, rubber latex (RFL) and chloro-modified resorcin (P) to a polyester fiber to which a polyepoxide compound has been applied in advance. A polyester fiber cord for reinforcing a hose characterized by satisfying the following requirements.
(A) R / F = 1 / 0.5 to 1/3 (molar ratio)
(B) RF / L = 1/3 to 1/15 (weight ratio)
(C) P / RFL = 1/1 to 1/5 (weight ratio)
(D) RF ripening time: 4 to 8 hours (E) The rubber latex contains an ethylenically unsaturated acid-modified vinylpyridine / styrene / butadiene rubber latex (modified VP) and a polybutadiene rubber latex (PB). And modified VP / PB = 90 / 10-50 / 50 (dry weight ratio).
(In the formula, R represents the amount of resorcin, F represents the amount of formalin, L represents the amount of rubber latex, P represents the amount of chloro-modified resorcin, RF represents the amount of resorcin / formalin, and RFL represents the amount of resorcin / formalin / rubber latex. The modified VP represents the amount of ethylenically unsaturated acid-modified vinylpyridine / styrene / butadiene rubber latex, and PB represents the amount of polybutadiene rubber latex.) The polyester fiber cord for hose reinforcement according to claim 1 , wherein the Gurley bending stiffness of the polyester fiber cord for hose reinforcement is 500 to 2000 mg. The polyester fiber cord for hose reinforcement according to claim 1 or 2 , wherein the polyester fiber cord for hose reinforcement is for an automobile brake hose.

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