JP6031917B2 - 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 during cord production, that is, polyester. The present invention relates to a polyester fiber cord for reinforcing a hose in which the removal of the treatment agent on the surface of the fiber cord is improved. The present invention also relates to a polyester fiber cord for reinforcing a hose that can provide a hose having excellent liquid leakage resistance in a crimped portion and a hose having excellent fatigue resistance.

  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, in the cord manufacturing process where adhesive treatment is performed, when the cord treated with adhesive rubs against the guides, the adhesive drops, adheres to the guides, and scatters, which impairs productivity and the work environment. The problem is also raised.

  Also, when fiber cords are used as reinforcements for hoses such as automobile brake hoses and car air conditioner hoses, metal fittings can be used because the hose is subject to heat aging, or the hose is repeatedly exposed to heat cycles from high to low temperatures. In addition, there is a problem that liquid leakage from the crimped portion of the hose is likely to occur.

  Furthermore, in applications that are used under severe conditions such as automobile brake hoses and require accurate stress transmission, it is strongly required to have practical fatigue resistance.

  As an attempt to solve the above problem, a polyethylene naphthalate fiber to which a polyepoxide compound has been previously attached is twisted, or a fiber cord to which a polyepoxide compound is attached after the polyethylene naphthalate fiber has been twisted is applied to resorcin, formalin. , A method of applying a treatment agent containing rubber latex (RFL), a blocked isocyanate compound, and chloro-modified resorcinol is disclosed (Patent Document 1).

  Also disclosed is a technique for performing multistage treatment of one stage or two or more stages by combining a treatment liquid containing chloro-modified resorcin, a treatment liquid containing a blocked isocyanate compound, a treatment liquid containing an epoxy compound, and an RFL mixed liquid. (Patent Document 2).

  Furthermore, a technique is disclosed in which a polyester fiber preliminarily provided with a polyepoxide compound is treated with a treating agent containing a specific composition of resorcin / formalin / rubber latex and a chlorophenol compound (Patent Document 3).

JP 2004-316027 A JP 2006-2327 A JP 2008-7929 A

  However, according to the above method, it is not possible to obtain a polyester fiber cord for reinforcing a hose that satisfies the adhesiveness with EPDM rubber, good process passage in the manufacturing process, liquid leakage resistance, and fatigue resistance at the same time. It is.

  In view of the background of the 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 cord production. The present invention aims to provide a polyester fiber cord for reinforcing a hose having improved liquid leakage resistance at the crimped portion by improving (dropping off the adhesive on the surface of the polyester fiber cord). Furthermore, the present invention intends to provide a polyester fiber cord for reinforcing a hose that can provide a hose excellent in fatigue resistance.

  The present invention employs the following means in order to solve such problems.

  (1) Polyester fiber is coated with a first treatment agent containing at least three kinds of (A) polyepoxide compound, (B) rubber latex, and (C) chloro-modified resorcin, and further, resorcin / formalin / rubber latex ( RFL) is a polyester fiber cord for reinforcing a hose that is coated with a second treatment agent, and (C) chloro-modified resorcin contained in the first treatment agent is 100% by weight of the solid content of the first treatment agent. A polyester fiber cord for reinforcing rubber characterized by being 0.2 to 10% by weight.

  (2) The (B) rubber latex contained in the first treatment agent is 30 to 70% by weight with respect to 100% by weight of the solid content of the first treatment agent, as described in (1) above Polyester fiber cord for hose reinforcement.

  (3) The above (1), wherein (C) chloro-modified resorcin contained in the first treating agent is 0.5 to 5% by weight with respect to 100% by weight of the solid content of the first treating agent. The polyester fiber cord for hose reinforcement as described in-(2).

  (4) The above (1) to (3), wherein the (A) polyepoxide compound contained in the first treatment agent is 30 to 70% by weight with respect to 100% by weight of the solid content of the first treatment agent. ) Polyester fiber cord for reinforcing hoses.

  (5) The rubber latex contained in the first treatment agent is a mixture of one or more kinds of rubber latex, and 50% of styrene-butadiene rubber latex is 100% by weight of the total solid content of the rubber latex. The polyester fiber cord for reinforcing a hose according to the above (1) to (4), which is contained in an amount of ˜100% by weight.

  (6) The total of the three kinds of (A) polyepoxide compound, (B) rubber latex, and (C) chloro-modified resorcin contained in the first treatment agent is 85 with respect to 100 wt% of the solid content of the first treatment agent. The polyester fiber cord for reinforcing a hose according to any one of (1) to (5), which is ˜100% by weight.

  That is, the present invention contains a polyepoxide compound, rubber latex, and chloro-modified resorcin in the first treatment agent, and controls the amount of chloro-modified resorcin to a very limited range, so that a conventional polyester fiber cord for reinforcing a hose is used. This makes it possible to simultaneously satisfy all the properties of adhesion to EPDM rubber, good process passability in the manufacturing process, liquid leakage resistance and fatigue resistance, which could not be achieved in any way.

  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 cord production (the surface of the polyester fiber cord) It is possible to provide a polyester fiber cord for reinforcing a hose which improves the drop-off of the RFL and has good liquid leakage resistance and fatigue resistance at the caulking portion.

FIG. 1 is a schematic diagram showing an inter-metal running friction tester that evaluates processability of fiber cords.

  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 with little dropping of the RFL adhesive from the cord at the time of manufacturing the hose, and liquid leakage resistance at the caulking portion has been obtained.

  Hereinafter, the present invention will be described in detail.

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

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

  In order for the polyester fiber used in the polyester fiber cord for reinforcing a hose of the present invention to have chemical durability, it is advantageous that the viscosity is high, the number of carboxyl end groups is small, and the amount of diethylene glycol is small.

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

  In the first treatment agent of the present invention, it is necessary to mix (A) a polyepoxide compound from the viewpoint of improving adhesiveness and liquid leakage resistance.

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

  The polyepoxide compound (A) is preferably contained in an amount of 30 to 70% by weight and more preferably 35 to 65% by weight with respect to 100% by weight of the total solid content of the first treatment agent. If it is less than 30% by weight, the adhesive strength, liquid leakage resistance and process passability may be lowered, and if it is more than 70% by weight, the adhesive force and liquid leakage resistance may be lowered and the fatigue resistance is lowered. there's a possibility that.

  In the first treatment agent of the present invention, it is necessary to mix (B) rubber latex from the viewpoint of improving adhesiveness and liquid leakage resistance.

  The rubber latex used as the treating agent in the present invention includes natural rubber latex, styrene-butadiene rubber latex, acrylonitrile-butadiene rubber latex, chloroprene rubber latex and vinylpyridine-styrene-butadiene rubber latex, polybutadiene latex, ethylene-propylene non- Conjugated diene terpolymer rubber latex and the like can be used, and these can be used alone or in combination, but from the viewpoint of process passability and adhesiveness, 100% by weight of the total solid content of rubber latex A rubber latex in which styrene-butadiene rubber latex occupies 50 to 100% by weight is preferable, and 60 to 100% by weight is more preferable. If it is less than 50% by weight, the process passability and liquid leakage resistance may be deteriorated.

  (B) The rubber latex is preferably contained in an amount of 30 to 70% by weight and more preferably 35 to 65% by weight with respect to 100% by weight of the total solid content of the first treatment agent. If the amount is less than 30% by weight, the adhesive force and the liquid leakage resistance may be lowered, and if it is more than 70% by weight, the adhesive force and the liquid leakage resistance may also be lowered.

  In the first treatment agent of the present invention, it is necessary to mix (C) chloro-modified resorcin from the viewpoint of improving adhesiveness and process passability. The chloro-modified resorcin used in the present invention is a compound represented by the following general formula.

However, W in the formula is CH ₂ , S, S—S, at least part of X and Y represents Cl, and the rest is selected from Br, I, H, OH and a C ₁ -C ₆ alkyl group. M is an integer of 1-15. Note that at least a part of the above formula includes a resorcin skeleton. The chloro-modified resorcin represented by the above formula is a halogenated phenol compound and formaldehyde, an initial condensate of other phenol compounds as an optional component, a sulfur-modified resorcin and formaldehyde, an initial condensate of other phenol compounds as an optional component or a halogen. This is an initial condensate of sulfur fluoride-modified resorcin and formaldehyde and an optional other phenol compound, and is obtained by using a raw material having a chlorine substituent in at least a part of the raw material and a raw material having a resorcin skeleton (one kind of The raw material may have a chlorine substituent and a resorcin skeleton).

  The method for preparing these chloro-modified resorcins is not particularly limited. For example, as a halogenated phenol having a chlorine substituent, parachlorophenol, orthochlorophenol and the like can be mentioned as starting materials, and parachlorophenol is preferred. . In addition to these, it is preferable to use parabromophenol, paraiodophenol, resorcin, orthocresol, paracresol, paratertiary butylphenol, 2,5-dimethylphenol and the like as starting materials, among them, resorcin, parabromophenol, Paracresol and paratertiary butylphenol are more preferable, and it is particularly preferable to use resorcin together.

  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.

  It is necessary that (C) the chloro-modified resorcin is contained in an amount of 0.2 to 10% by weight with respect to 100% by weight of the total solid content of the first treatment agent. When the amount is less than 0.2% by weight, the adhesiveness and process passability deteriorate, and when it exceeds 10% by weight, the liquid leakage resistance and process passability deteriorate. Moreover, the preferable compounding quantity of (C) chloro modified resorcin is 0.5-5 weight% with respect to 100 weight% of total solid content of a 1st processing agent. If it is less than 0.5% by weight, the adhesiveness and process passability may be deteriorated. If it is more than 5% by weight, the liquid leakage resistance and process passability may be deteriorated.

  The total of the three types of (A) polyepoxide compound, (B) rubber latex, and (C) chloro-modified resorcin contained in the first treating agent of the present invention is 85 to 85% based on 100% by weight of the solid content of the first treating agent. It is preferably 100% by weight, more preferably 90 to 100%. If it is less than 85% by weight, the process passability and liquid leakage resistance may be deteriorated.

  Blocked polyisocyanate may be mixed with the 1st processing agent of this invention from a viewpoint of improving adhesiveness.

  The blocked isocyanate compound used in that case includes polyisocyanate compounds such as tolylene diisocyanate, metaphenylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, triphenylmethane triisocyanate and phenols such as phenol, cresol and resorcin, ε- Reactions with lactams such as caprolactam and valerolactam, oximes such as acetoxime, methylethylketoxime, cyclohexaneoxime, and blocking agents such as ethyleneimine are used, and the blocking agent is released by heating to produce an active isocyanate compound. Is. Among these compounds, aromatic polyisocyanate compounds blocked with methyl ethyl ketoxime and aromatic compounds of diphenylmethane diisocyanate are particularly preferably used.

  The blocked isocyanate that can be used in the present invention preferably has a dissociation temperature between the polyisothiocyanate compound and the blocking agent of 120 ° C to 180 ° C, more preferably 150 ° C to 170 ° C. . If the dissociation temperature is less than 120 ° C, the adhesion may be insufficient, and if it exceeds 180 ° C, the cord becomes hard and fatigue resistance may be insufficient when used as a hose application.

  The blocked polyisocyanate compound that can be used in the present invention is preferably 0 to 15% by weight, particularly 0 to 10% by weight, based on 100% by weight of the total solid content of the first treatment agent. It is good. If it exceeds 15% by weight, the liquid leakage resistance and fatigue may be deteriorated.

  The hose reinforcing cord of the present invention needs to be coated with resorcin / formalin / rubber latex (RFL) as the second treating agent after the first treating agent and the heat treatment.

  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 preferable that it is 1/3. More preferably, it is the range of 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 may be lowered or the process passability may be deteriorated.

  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 adjust the molar ratio of resorcin to formaldehyde to 1/1 to 1/3 by adding formaldehyde after dissolving in an alkaline catalyst aqueous dispersion. 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, styrene-butadiene rubber latex, acrylonitrile-butadiene rubber latex, chloroprene rubber latex and vinylpyridine-styrene-butadiene rubber latex, ethylene-propylene-nonconjugated. Diene terpolymer rubber latex and the like can be mentioned, and these can be used alone or in combination. From the viewpoint of heat resistance and adhesiveness, vinyl pyridine A rubber latex in which the styrene-butadiene terpolymer rubber latex accounts for 10% by weight or more is preferable, and 10 to 70% by weight is preferable.

  In particular, when the adherend rubber is an ethylene-propylene-diene terpolymer rubber (EPDM rubber) that is preferably used for a brake hose, polybutadiene rubber latex (PB) and vinylpyridine-styrene-butadiene rubber latex It is preferable to use a mixed rubber latex containing (VP), and the mixing ratio of the rubber latex is PB / VP = 90/10 to 30/70, more preferably 80/20 to 40/60 in terms of solid content dry weight ratio. is there. When the PB / VP ratio exceeds 90/10, the process passability may deteriorate, and when the PB / VP ratio is less than 30/70, the adhesiveness may decrease.

  Furthermore, the blending ratio of resorcin / formalin / rubber latex resorcin / formalin and rubber latex is preferably RF / L = 1/3 to 1/15 in terms of solid content, more preferably 1/5 to 1. / 12. When the RF / L ratio is out of this range, the adhesiveness may be lowered or the process passability may be deteriorated.

  It is preferable to mix (C) chloro modified resorcin to the 2nd processing agent of this invention from a viewpoint of improving adhesiveness and process passability.

  The (C) chloro-modified resorcin is preferably contained in an amount of 5 to 30% by weight, more preferably 5 to 25% by weight, based on 100% by weight of the total solid content of the second treatment agent. If the amount is less than 5% by weight, the adhesion may be deteriorated. If the amount is more than 30% by weight, the process passability and liquid leakage resistance may be deteriorated.

  In the treating agent used in the present invention, the aging conditions of resorcin (R) and formalin (F) are preferably aged for 2 to 8 hours, more preferably 5 to 7 hours, at 20 to 30 ° C. . 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.

  Further, the ripening condition of RFL is preferably 14 to 48 hours under a condition of 20 to 30 ° C., and more preferably 16 to 36 hours. If it is out of this range, the adhesiveness may decrease.

  From the viewpoint of improving adhesiveness, a blocked polyisocyanate may be mixed in the second treating agent of the present invention.

  The blocked isocyanate compound used in that case includes polyisocyanate compounds such as tolylene diisocyanate, metaphenylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, triphenylmethane triisocyanate and phenols such as phenol, cresol and resorcin, ε- Reactions with lactams such as caprolactam and valerolactam, oximes such as acetoxime, methylethylketoxime, cyclohexaneoxime, and blocking agents such as ethyleneimine are used, and the blocking agent is released by heating to produce an active isocyanate compound. Is. Among these compounds, aromatic polyisocyanate compounds blocked with methyl ethyl ketoxime and aromatic compounds of diphenylmethane diisocyanate are particularly preferably used.

  The blocked isocyanate that can be used in the present invention preferably has a dissociation temperature between the polyisothiocyanate compound and the blocking agent of 120 ° C to 180 ° C, more preferably 150 ° C to 170 ° C. Is good. If the dissociation temperature is less than 120 ° C, the adhesion may be insufficient, and if it exceeds 180 ° C, the cord becomes hard and fatigue resistance may be insufficient when used as a hose application.

  The blocked polyisocyanate compound is preferably contained in an amount of 5 to 30% by weight, more preferably 5 to 20% by weight based on 100% by weight of the total solid content of the second treating agent. If it is less than 5% by weight, the adhesive strength may be lowered, and if it is more than 30% by weight, fatigue resistance may be lowered.

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

  Polyester fibers are twisted to form untreated cords. Here, although the twist form can be applied by either single twist or various twists, it is preferable that the polyester fiber cord for hose reinforcement of the present invention is subjected to single twist. The twist number is preferably 5t to 20t / 10cm, more preferably 6t to 18t / 10cm. If it is less than 5t / 10cm, the fatigue resistance of the hose may be insufficient, and if it is 20t / 10cm or more, the cord may be crimped and process passability may be deteriorated.

  Next, the treatment agent of the present invention is applied to the untreated cord. The total solid content concentration of the treatment agent used in the present invention is preferably 5 to 30% by weight, more preferably 7 to 28% 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. For example, it can be processed using a Rituler computer treater or a multi-cylinder type code setter.

  The adhesion amounts of the first treatment agent and the second treatment agent to the polyester fiber are each preferably 0.5 to 6% by weight, particularly 1.5 to 5% by weight relative to the dry weight. Adhesiveness with rubber and process passability are improved. The amount of adhesion can be controlled, for example, by setting the adhesive concentration and the liquid removal conditions after immersion in the adhesive liquid.

  The heat treatment after applying the first treatment agent and the second treatment agent to the polyester fiber is each dried at 80 to 180 ° C. for 0.5 to 5 minutes, more preferably 1 to 3 minutes, and then 150 to 260 ° C. The heat treatment is preferably performed at a temperature of 200 ° C. to 250 ° C. for 0.5 to 5.0 minutes, more preferably 1 to 3 minutes. In order to control the physical properties of the cord, drying is preferably performed with 0 to 3% stretch, and heat treatment with 0 to 3% stretch and then 0 to 3% relaxation. If the heat treatment temperature is too low, adhesion to the adherend rubber will be insufficient. On the other hand, if the heat treatment temperature is too high, the polyester fibers will melt, fuse, become hard, and cause a strong deterioration. No longer served.

  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.

  Furthermore, in the present invention, at least a portion in contact with the hose reinforcing polyester fiber cord is an ethylene / α-olefin / non-conjugated diene rubber compound (EPDM rubber) and is reinforced with the hose reinforcing polyester fiber cord. It is preferable that the automobile brake hose be formed.

  As the shape of the brake hose of the present invention, conventionally known ones can be applied, but the reinforcing fiber is wound on one or more layers on the inner rubber, and the outer rubber is coated thereon. Those are preferred.

  As a method of winding the reinforcing fiber cord, there are a blade method in which one fiber cord and the other fiber cord are alternately wound up and down, a spiral method in which one fiber cord is wound and the other fiber cord is wound. There are shapes in which the reinforcing fiber cords are in close contact with each other and shapes in which the reinforcing fiber cords are spaced from each other, but there is no particular designation.

  The rubber hose vulcanization method includes vulcanization under dry heat and vulcanization under steam, and is usually performed at 150 ° C. to 160 ° C. for 30 minutes to 1 hour, but the vulcanization method, vulcanization time and vulcanization are performed. Conditions such as sulfur temperature may be appropriately selected.

  In the hose of the present invention, it is only necessary that the EPDM rubber is disposed in contact with the hose reinforcing polyester fiber cord, and there is no problem even if the types of the inner layer rubber and the outer layer rubber are different. For example, a reinforcing fiber cord is double braided on an inner tube of an unvulcanized EPDM rubber composition, and an unvulcanized EPDM rubber is coated thereon, followed by vulcanization.

  Since the automobile brake hose of the present invention has good adhesion between rubber and cords and good liquid leakage resistance at the caulked portion, it exhibits practical fatigue resistance as a brake hose.

  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 evaluation method of the rubber reinforcing cord is as follows.

(1) Cord 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 pressing pressure was adjusted so that the surface pressure of the rubber and the fiber cord was 3 MPa. The size of the aluminum plate and the area around which the fiber cord is wound may be arbitrary, and the tension at the time of winding is 0.5 cN / dtex. After standing to cool, the rubber side sample to which the cord was bonded was taken from the aluminum plate, and the sample was further cut into a width of 20 mm. While this sample was kept at an angle of 90 ° at a speed of 50 mm / min in an environment of 20 ° C., the peel force when the fiber cord was peeled from the rubber was displayed as N / 20 mm. . The n number was 4.

(2) Amount of treatment agent adhesion The amount was determined by the mass method of JIS L1017 (1995).

(3) Process passability One fiber cord was set in the inter-metal running friction tester shown in FIG. 1, and the adhesion state of debris to the guides when the fiber cord was run 1000 m was used as an index. The residue attached to the guides was collected and weighed. FIG. 1 shows an inter-metal running friction tester, which feeds a cord from a measurement fiber cord sample 1 at a speed of 20 m / min. The speed is adjusted by the number of rotations of the nip roller 2 for yarn feeding. Further, the load 3 is adjusted so that the tension measured at the entry side tension measurement position 4 is 1000 g. The cord is abraded with a satin chrome plating tube 5 and debris adheres to the plating tube. Thereafter, it passes through the tension measuring roll 6 on the exit side, and further passes through the nip roller 2 for feeding the upper thread.
Friction body: satin chrome plated tube friction body temperature: 25 ° C. with a diameter of 40 mm and a surface roughness of 12.5Z (JIS-B0601-1994, ten-point average roughness)
Temperature and humidity of measurement chamber: 25 ° C, 65%
Contact angle: 180 ° Tension on the friction body containing side T ₁ : 1000 g
Yarn speed: 20 m / min n number was 2.

(4) Liquid leakage resistance The liquid leakage resistance was evaluated by the air diffusion value. The air diffusion value was measured as follows. Place the polyester fiber cord for hose reinforcement between two rubber plates so that the two cords cross, press vulcanize at 160 ° C for 30 minutes, and measure the piece with a cord length of 5 cm. create. The measurement piece is left in an air circulation type dry heat furnace set at 100 ° C. for one week, taken out and allowed to cool to room temperature. Makes it possible to apply a constant air pressure to one end face of the measuring piece where the cord end face is exposed, and to calculate the air permeability permeating through the cord to the other end face from the change in the height of the water column. . An air diffusion value (AD value) was obtained by determining the moving distance of the water surface when the air pressure was 0.2 MPa and left for 10 minutes. It means that the smaller the AD value, the smaller the liquid leakage when using a hose. The rubber having the composition shown in Table 1 was used. The n number was 4.

(5) Fatigue resistance Under the temperature condition of 100 ° C., each hose is bent at 0 MPa → 9.8 MPa → 0 MPa → 9.8 MPa while applying an impulse pressure, and the hose is repeatedly bent. The number of bends when it broke was measured. The n number was 4.

(Examples 1-8), (Comparative Examples 1-4)
(A) “Denacol” EX614B (manufactured by Nagase Kasei Co., Ltd.) as the polyepoxide compound, (B) rubber latex, (C) “Denabond E” (manufactured by Nagase Kasei Kogyo Co., Ltd.) as the chloro-modified resorcin, and blocked poly A first treatment agent having a solid content concentration of 25% by weight was prepared by mixing “Elastolon” BN27 (Daiichi Kogyo Seiyaku Co., Ltd.) as an isocyanate compound in a proportion shown in Table 2 in terms of solid content.

  Next, the second treating agent was prepared by the following method.

  Resorcin (R) is added to an aqueous caustic soda solution and sufficiently stirred and dispersed. To this, formalin (F) was added so that the R / F ratio was 1 / 1.5 (molar ratio), mixed uniformly, and aged at 25 ° C. for 4 hours. Next, “Nippol 2518FS” (manufactured by Nippon Zeon Co., Ltd., vinylpyridine / styrene / butadiene rubber latex) and “Nippol LX-111A” (manufactured by Nippon Zeon Co., Ltd., polybutadiene rubber latex) are mixed (vinylpyridine). -Styrene-butadiene rubber latex / polybutadiene rubber latex = 50/50 (weight ratio)) and the resorcin / formalin initial condensate dispersion in a solid content ratio (RF / L ratio) of 1/9, Aging was carried out at a temperature of 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 ratio of RFL and solid content (RFL / “Denabond”) was 4/1, and stirred sufficiently. Aged at 25 ° C. for 20 hours. The final treatment solution concentration was 13%.

  B in Table 2 is the following rubber latex.

B-1: Styrene-butadiene rubber latex “Nippol LX110” (Nippon Zeon Corporation)
B-2: Vinylpyridine-styrene-butadiene rubber latex “Nippol 2518FS” (Nippon Zeon Corporation)
B-3: Polybutadiene rubber latex “Nippol LX111A” (Nippon Zeon Corporation)

  On the other hand, in the yarn production process, one multifilament of polyester fiber (T705M (1670 dTex) manufactured by Toray Industries, Inc.) was subjected to a single twist of 8 t / 10 cm to obtain a twisted yarn cord.

  The untreated code is immersed in the first treatment agent using a compute treater (CA Ritzler), then dried at 120 ° C. for 1 minute (dry treatment), and then at 240 ° C. for 1 minute. Heat treatment (hot treatment) was performed. Subsequently, after immersing in the second treatment agent, drying is performed at 120 ° C. for 1 minute (dry treatment), followed by heat treatment at 240 ° C. for 0.5 minutes (hot treatment), and heat treatment at 240 ° C. for 0.5 minutes. (Normalization processing) was performed.

  The cord thus obtained was measured for the air diffusion value, the cord peeling adhesion and the process passability as described above. The results are shown in Table 2.

  Further, the EPDM rubber compound shown in Table 1 is extruded with an extruder to form an inner tube, and the above processing cord obtained above is bladed at a crossing angle of 108 degrees, and the outer EPDM rubber is the same as the inner tube rubber. The blend was extrusion coated as an outer tube. It was wound into a long shape and vulcanized in a steam can at 160 ° C. for 30 minutes to produce a reinforced rubber hose having an inner diameter of 16 mm and an outer diameter of 24 mm. Fittings were attached to both ends of the hose, and fatigue resistance was measured. The results are shown in Table 2.

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

1: Fiber cord sample for measurement 2: Nip roller for yarn feeding 3: Load 4: Incoming side tension measuring position 5: Satin chrome plated tube 6: Outside tension measuring roll

Claims (7)

  The polyester fiber is coated with a first treatment agent containing at least three kinds of (A) polyepoxide compound, (B) rubber latex, and (C) chloro-modified resorcin, and further, resorcin / formalin rubber latex (RFL) is used as an outer layer thereof. The (C) chloro-modified resorcin is a polyester fiber cord for reinforcing rubber that is coated with the second treating agent and is contained in the first treating agent, with respect to 100% by weight of the solid content of the first treating agent. 0.2 to 10% by weight of a polyester fiber cord for reinforcing rubber.   2. The rubber reinforcing polyester according to claim 1, wherein (B) the rubber latex contained in the first treatment agent is 30 to 70 wt% with respect to 100 wt% of the solid content of the first treatment agent. Fiber cord. Wherein (C) chloro modified resorcin contained in the first treatment agent, any of claim 1-2, characterized in that the solids content 100 wt% of the first treatment agent is 0.5 to 5 wt% polyester fiber cord for reinforcing rubber according to any. According to any one of claims 1 to 3, wherein the (A) polyepoxide compound contained in the first treatment agent is 30 to 70 wt% based on the solids content of 100 wt% of the first treatment agent Polyester fiber cord for rubber reinforcement. The rubber latex contained in the first treatment agent is a mixture of one or more kinds of rubber latex. The styrene-butadiene rubber latex is 50 to 100% by weight with respect to 100% by weight of the total solid content of the rubber latex. %, The polyester fiber cord for rubber reinforcement according to any one of claims 1 to 4. The total of the three types (A) polyepoxide compound, (B) rubber latex, and (C) chloro-modified resorcin contained in the first treatment agent is 85 to 100% by weight based on 100% by weight of the solid content of the first treatment agent. The polyester fiber cord for rubber reinforcement according to any one of claims 1 to 5 , wherein the polyester fiber cord is for rubber reinforcement. A hose reinforced with the polyester fiber cord for rubber reinforcement according to any one of claims 1 to 6.

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