JP5157065B2 - Rubber composition for hose and hose - Google Patents

Description

  The present invention relates to a rubber composition for a hose and a hose, and in particular, has a high green modulus (elastic modulus of rubber before vulcanization), excellent flowability (fluidity) under extrusion temperature conditions, and under subsequent vulcanization temperature conditions. The present invention relates to a rubber composition capable of producing a high-quality hose with excellent extrudability and dimensional stability by reducing flowability, and a hose produced using the rubber composition.

  As shown in FIG. 1, various fluid transport hoses such as a hot water supply hot water hose have an inner tube rubber layer 1, an intermediate rubber layer 2, and a jacket rubber layer 3 that are made of braided layers of metal hard wires or reinforcing yarns or each other. In this structure, the layers are laminated via a reinforcing layer (first reinforcing layer 4 and second reinforcing layer 5) formed of spiral layers wound in a pairing direction.

  In such a hose, the inner tube rubber layer 1 is usually extruded to a predetermined thickness on a mandrel, and then a first reinforcing layer 4 is formed by winding a metal hard wire or a reinforcing thread, and this first reinforcing layer is formed. The intermediate rubber layer 2 is extruded on the layer 4 to a predetermined thickness, and further, a metal hard wire or a reinforcing thread is wound on the intermediate rubber layer 2 to form a second reinforcing layer 5. The outer rubber layer 3 is extruded to a predetermined thickness and finally heated and vulcanized.

  Conventionally, in such a hose forming process, there has been a problem referred to as “cutting rubber” or “going rubber” as described below.

[Rubber out]
When the rubber layer is extruded, tension is always applied to the extruded rubber sheet. Therefore, if the rubber has a low green modulus, the rubber sheet yields due to the tension, and a “rubber cut” occurs in which the extruded rubber sheet is cut.
In particular, among the rubber layers constituting the hose, the intermediate rubber layer is required to be thin in order to make the hose slim. Therefore, it is easy to generate a rubber breakage by applying tension to the thin rubber sheet.

[Rubber rise]
“Rubber going up” is a phenomenon in which the rubber layer on the inner layer side rises to the outside through the gap between the reinforcing layers during vulcanization. For example, the inner tube rubber passes through the reinforcing layer, the intermediate rubber layer, and the outer rubber layer. It rises through the layer, or the intermediate rubber layer rises and bites into the outer rubber layer. This is because rubber develops flowability under vulcanization temperature conditions.

  Conventionally, in order to prevent rubber breakage, short fibers such as natural cellulose have been blended into the rubber composition forming the rubber layer, but in order to sufficiently increase the green modulus and prevent rubber breakage. It is necessary to mix at least about 10 parts by weight of short fibers with respect to 100 parts by weight of the rubber component. However, when a large amount of short fibers are blended, the green modulus increases, but the rubber skin due to extrusion molding deteriorates, the dimensional stability is further impaired, and the dimensions of the hose itself are not stable. In addition, the extrudability deteriorates and a partial vulcanization reaction called “yake” occurs.

  There is a possibility that the green modulus can be increased with a small amount by using an aromatic polyamide fiber with high rigidity of the fiber itself. However, since the aromatic polyamide fiber has a weak interaction with rubber, the green modulus is improved. The effect is not enough.

  In addition, blending of short fibers is effective for suppressing rubber rise, but again, a large amount of blending is necessary to obtain a sufficient effect. It leads to deterioration of stability and further deterioration of extrudability.

  The present invention solves the above-described conventional problems, and there is no problem of running out of rubber or rubber, and a rubber composition capable of producing a high-quality hose with excellent extrudability and dimensional stability, and the rubber composition It aims at providing the hose manufactured using the.

The rubber composition for a hose of the present invention (Claim 1) is a rubber composition for forming a rubber layer of a hose , which includes a polyketone fiber, and the polyketone fiber has an average length of 0.1. It is a short fiber of -50 mm, and the content of the polyketone fiber is 0.5-50 parts by weight with respect to 100 parts by weight of the rubber component .

Rubber composition for a hose of 請 Motomeko 2 resides in that in Claim 1, the average fiber diameter of the polyketone fiber is characterized in that it is a 1 to 1000 m.

A rubber composition for a hose according to claim 3 is characterized in that, in claim 1 or 2 , the polyketone fiber is a fiber of a polyketone resin represented by the following general formula (I).

（（Ｉ）式中、Ｒはエチレン性不飽和化合物由来の連結基であり、各繰り返し単位において、同一であっても異なっていても良い。）

(In the formula (I), R is a linking group derived from an ethylenically unsaturated compound, and each repeating unit may be the same or different.)

The rubber composition for a hose according to claim 4 is characterized in that, in claim 3 , R in the general formula (I) is a connecting group derived from ethylene.

A rubber composition for a hose according to claim 5 is the rubber composition according to claim 3 or 4 , wherein the polyketone resin has a degree of polymerization of 1.0 to 10.0 dL / g measured in m-cresol at 60 ° C. It is characterized by having a certain degree of polymerization.

The hose of the present invention (Claim 6 ) is characterized by including a rubber layer made of the rubber composition for a hose according to any one of Claims 1 to 5 .

A hose according to a seventh aspect is the hose according to the sixth aspect, wherein the inner rubber layer, the intermediate rubber layer, and the outer rubber layer are laminated between the respective rubber layers via a reinforcing layer, and at least the intermediate rubber layer Is formed from the rubber composition.

  Polyketone fiber is excellent in rigidity, adhesion to rubber, dispersibility, and interaction with carbon black blended as a filler, and can increase the green modulus of rubber composition with a small blending amount. Further, it is possible to prevent the rubber from being cut without impairing the dimensional stability. The polyketone fiber maintains the excellent flowability and extrudability of the rubber composition by taking an α-type crystal form under an extrusion molding temperature condition of about 100 ° C., while vulcanizing at about 140 to 190 ° C. Under the temperature condition, the polyketone fiber contracts by taking the β-type crystal form, and the flow property is reduced, thereby suppressing the rubber from rising.

  Therefore, according to the rubber composition for a hose of the present invention blended with polyketone fibers, the green modulus is high, the flow property is excellent in the extrusion temperature condition, and the flow property is reduced in the subsequent vulcanization temperature condition. A high quality hose can be manufactured with excellent extrudability and dimensional stability by preventing rubber breakage and rubber rise.

In the present invention, it is preferable that the average fiber diameter of port Riketon fiber is 1 to 1000 m (Claim 2).

In the present invention, the polyketone resin constituting the polyketone fiber is preferably a polyketone resin represented by the following general formula (I) (Claim 3 ), and R is a connecting group derived from ethylene (Claim 4 ). the degree of polymerization, in m- cresol, is preferably a solution viscosity measured at 60 ° C. is the degree of polymerization in the range of 1.0~10.0dL / g (claim 5).

（（Ｉ）式中、Ｒはエチレン性不飽和化合物由来の連結基であり、各繰り返し単位において、同一であっても異なっていても良い。）

(In the formula (I), R is a linking group derived from an ethylenically unsaturated compound, and each repeating unit may be the same or different.)

The hose of the present invention is provided with a rubber layer comprising such a rubber composition for a hose of the present invention. In particular, an inner tube rubber layer, an intermediate rubber layer, and an outer rubber layer are disposed between the rubber layers. a hose laminated through a reinforcing layer, it is preferable that at least the intermediate rubber layer is formed from the rubber composition (claim 7).

  Hereinafter, embodiments of the rubber composition for a hose and the hose of the present invention will be described in detail.

  First, the polyketone fiber used in the present invention will be described.

  The polyketone fiber used in the present invention is preferably produced using a polyketone resin represented by the following general formula (I) as a raw material.

（（Ｉ）式中、Ｒはエチレン性不飽和化合物由来の連結基であり、各繰り返し単位において、同一であっても異なっていても良い。）

(In the formula (I), R is a linking group derived from an ethylenically unsaturated compound, and each repeating unit may be the same or different.)

  The polyketone resin is an alternating copolymer in which CO units (carbonyl groups) and units derived from an ethylenically unsaturated compound are arranged in the molecule, that is, for example, ethylene units next to each CO unit in the polymer chain. It is a structure in which olefin units such as are located one by one. The polyketone resin may be a copolymer of carbon monoxide and one specific ethylenically unsaturated compound, or a copolymer of carbon monoxide and two or more ethylenically unsaturated compounds. May be.

  Examples of the ethylenically unsaturated compound forming R in (I) include unsaturated hydrocarbon compounds such as ethylene, propylene, butene, pentene, hexene, heptene, octene, nonene, decene, dodecene, styrene, methyl acrylate, Examples thereof include unsaturated carboxylic acids such as methyl methacrylate, vinyl acetate, and undecenoic acid or derivatives thereof, as well as undecenol, 6-chlorohexene, N-vinylpyrrolidone, and diethyl ester of sulphonylphosphonic acid. These may be used alone or in combination of two or more, but in particular from the viewpoint of the mechanical properties and heat resistance of the polymer, a polyketone using an ethylenically unsaturated compound mainly composed of ethylene Resins are preferred.

  When ethylene and another ethylenically unsaturated compound are used in combination as the ethylenically unsaturated compound constituting the polyketone resin, ethylene is used so as to be 80 mol% or more based on the total ethylenically unsaturated compound. preferable. If this ratio is less than 80 mol%, the melting point of the resulting polymer may be 200 ° C. or lower, and the resulting polyketone fiber may have insufficient heat resistance. In view of the mechanical properties and heat resistance of the polyketone fiber, the amount of ethylene used is preferably 90 mol% or more with respect to the total ethylenically unsaturated compound. The polyketone can be produced according to a known method, for example, a method described in European Patent Publication Nos. 121965, 213671, 229408 and US Pat. No. 3,914,391.

  The polymerization degree of the polyketone resin is preferably such that the solution viscosity measured at 60 ° C. in m-cresol is in the range of 1.0 to 10.0 dL / g. If the solution viscosity is less than 1.0 dL / g, the resulting polyketone fiber may have insufficient mechanical strength. From the viewpoint of the mechanical strength of the polyketone fiber, the solution viscosity is more than 1.2 dL / g. preferable. On the other hand, if the solution viscosity exceeds 10.0 dL / g, the melt viscosity at the time of fiberization and the solution viscosity may become too high, resulting in poor spinnability. From the viewpoint of spinnability, the solution viscosity is 5.0 dL. / G or less is more preferable. In view of the mechanical strength and spinnability of the fiber, the solution viscosity is particularly preferably in the range of 1.3 to 4.0 dL / g.

  The method for fiberizing the polyketone resin is not particularly limited, but generally a melt spinning method or a solution spinning method is adopted. When adopting the melt spinning method, for example, according to the method described in JP-A-1-124617, the polymer is usually melt-spun at a temperature higher than the melting point by 20 ° C. or more, preferably about 40 ° C. higher than the melting point, Next, it is usually easy to stretch at a temperature lower than the melting point by 10 ° C. or less, preferably about 40 ° C. lower than the melting point, preferably at a stretch ratio of 3 times or more, more preferably at a stretch ratio of 7 times or more. Desired fibers can be obtained.

  On the other hand, when the solution spinning method is adopted, the polymer is added to, for example, hexafluoroisopropanol, m-cresol, etc. in an amount of 0.25 to 20% by mass, preferably 0.5 to 0.5% according to the method described in JP-A-2-112413. Dissolved at a concentration of 10% by mass, extruded from a spinning nozzle to be fiberized, and then removed and washed in a non-solvent bath such as toluene, ethanol, isopropanol, n-hexane, isooctane, acetone, methyl ethyl ketone, preferably in an acetone bath. To obtain a desired filament by drawing at a temperature in the range of (melting point−100 ° C.) to (melting point + 10 ° C.), preferably (melting point−50 ° C.) to (melting point). be able to. In addition, it is preferable to add an antioxidant to the polyketone resin for the purpose of imparting sufficient durability against heat, oxygen and the like, and a matting agent, a pigment, an antistatic agent, etc. are blended if necessary. can do.

Polyketone fiber used in the present invention is Ru short fibers der having an average fiber length 0.1 to 50 mm. If the fiber length of the polyketone fiber is too long, the moldability is impaired. On the other hand, if the fiber length is too short, it is not possible to sufficiently obtain the effect of improving rubber breakage and rubber rise due to the blending of the polyketone fiber.

  The polyketone fiber preferably has an average fiber diameter of 1 to 1000 μm. If the fiber diameter of the polyketone fiber is too thick, the moldability is impaired. On the other hand, if it is too thin, the effect of improving the rubber breakage and the rubber rise due to the blending of the polyketone fiber cannot be obtained sufficiently.

Such polyketone fibers, in the rubber composition, that is 0.5 to 50 parts by weight blended with respect to 100 parts by weight of the rubber component. If the blending amount of the polyketone fiber is too large, moldability is impaired. On the other hand, if the blending amount is too small, it is not possible to sufficiently obtain the effect of improving rubber breakage and rubber rising due to blending of the polyketone fiber.

  In the present invention, it is essential to blend polyketone fibers, but the polyketone fibers are blended in combination with other fibers such as natural cellulose, aromatic polyamide, nylon, polyethylene terephthalate (PET), and aramid. May be. However, when such other fibers are used in combination in order to obtain an excellent improvement effect of rubber breakage and rubber rise by the polyketone fiber, the amount used is preferably 10% by weight or less of the total fiber amount.

  In the present invention, except that polyketone fiber is blended in the rubber composition, it can be a usual rubber composition blend, and the blend composition is the use of the rubber composition, that is, the type of hose, the rubber to be applied. It is determined appropriately depending on the location of the layer.

For example, the rubber composition for a hose of the present invention can have the following composition.
Rubber component: 100 parts by weight Polyketone fiber: 0.5-50 parts by weight Filler (carbon black, etc.): 20-150 parts by weight Processing aid (oil, etc.): 0-80 parts by weight Anti-aging agent (6C, etc.): 0.3 to 5.0 parts by weight Vulcanizing agent (sulfur, etc.): 0.2 to 10 parts by weight Vulcanization accelerator (thiuram, sulfenamide, etc.): 0.2 to 10 parts by weight

  In addition, when mix | blending a short fiber with a rubber composition, in order to improve the adhesiveness with rubber | gum, a short fiber is normally given the adhesive improvement process called a dip process.

  Specifically, RFL treatment is performed in which short fibers are immersed in an RFL solution (R: resorcin, F: formalin, L: latex). Here, for R, in addition to resorcin, resorcinol-formaldehyde resin or naphthol can also be used. For F, in addition to formaldehyde, a methylene donor compound such as hexamethylenetetramine or hexamethylenemethylmelamine can also be used.

The latex of L is “a polymer substance stably dispersed in an aqueous medium”, and a polymer such as NR or SBR can be used as the polymer. The polymer can be freely selected depending on the rubber to be blended. RFL may be blended with silica (the pH of the silica to be applied can be freely selected depending on the formulation to be applied).
Prior to the RFL treatment, short fibers may be subjected to an electrical pretreatment such as plasma or corona or a pretreatment using a chemical substance such as an epoxy compound.

In the present invention, polyketone fibers are treated as RFL,
R: resorcin,
F: formaldehyde,
It is preferable to use a mixture of L: vinylpyridine-styrene butadiene copolymer emulsion: SBR = 7: 3 (weight ratio).

  When the hose of the present invention is a hose having the structure shown in FIG. 1, for example, as rubber components of the rubber composition constituting the inner tube rubber layer 1 and the outer cover rubber layer 3, generally butyl rubber (IIR), chlorine Butyl rubber (C1-IIR), chlorinated polyethylene, chlorosulfonated polyethylene, brominated butyl rubber (Br-IIR), isobutylene-bromoparamethylstyrene copolymer, EPR (ethylene-propylene copolymer), EPDM (ethylene- Propylene-diene terpolymer), NBR (acrylonitrile butadiene rubber), CR (chloroprene rubber), hydrogenated NBR, acrylic rubber, blends of two or more of these rubbers, or these rubbers as the main component A blend with a polymer, preferably a butyl rubber or EPDM rubber is used.

  The rubber type of the inner tube rubber layer 1 and the rubber type of the jacket rubber layer 3 may be the same or different.

  The rubber component of the rubber composition constituting the intermediate rubber layer 2 is not particularly limited as long as it has good adhesiveness to the inner tube rubber layer 1 and the outer cover rubber layer 3, and is usually NR (natural Rubber), NBR, SBR (styrene-butadiene rubber), CR and the like are used.

  The thickness of each rubber layer varies depending on the use of the hose. Usually, the inner tube rubber layer 1 has a thickness of 0.5 to 5 mm, the intermediate rubber layer 2 has a thickness of 0.1 to 1.0 mm, and the outer cover. The thickness of the rubber layer 3 is preferably 0.5 to 5 mm.

  There is no restriction | limiting in particular as a constituent material of the 1st, 2nd reinforcement layers 4 and 5, Although it can select suitably according to the objective, For example, metals, such as iron, copper, and aluminum, alloys, such as stainless steel, etc. Reinforcing yarns made of metal hard wires, organic fibers such as polyethylene terephthalate (PET) fibers, polyethylene naphthalate (PEN) fibers, nylon fibers, aramid fibers, and other carbon fibers, and inorganic fibers can be used. The reinforcing layers 4 and 5 are formed by braiding or spirally winding one of these alone or in combination of two or more to form a braided layer or a spiral layer wound in a pairing direction.

  Although there is no restriction | limiting in particular as the diameter of the metal hard wire which comprises the reinforcement layers 4 and 5, and the fineness of a reinforcement thread | yarn, It is preferable that the wire diameter of a metal hard wire is 0.1-0.5 mm. If the wire diameter of the metal hard wire is less than 0.1 mm, the metal hard wire is likely to bite into the inner surface layer, and the metal hard wire may be broken. In addition, if the wire diameter of the metal hard wire exceeds 0.5 mm, it is too thick to form the reinforcing layers 4 and 5.

  The fineness of the organic fiber reinforcing yarn is preferably 1100 to 3300 dtex. When the fineness of the reinforcing yarn is less than 1100 dtex, the strength and durability are insufficient, and when it exceeds 3300 dtex, the appearance may deteriorate due to being too thick.

  As shown in FIG. 1, in a hose having two layers of reinforcing layers, there are two layers of an organic fiber reinforcing layer made of a braided layer of organic fiber reinforcing yarn and a metal hard wire reinforcing layer made of a braided layer of metal hard wire. It is preferable to have a layered structure, and in particular, braided an organic fiber reinforcing layer braided with reinforcing yarns of 1100 to 3300 dtex, 6 to 15 twists / 10 cm, and metal hard wire with a wire diameter of 0.1 to 0.5 mm A two-layer structure having a metal hard wire reinforcing layer, or an organic fiber reinforcing layer in which reinforcing yarns of 1100 to 3300 dtex and 0 to 10 twists / twisting are wound spirally, and a wire diameter of 0.1 to 3 It is preferable to have a two-layer structure having a metal wire reinforcing layer braided with a 0.5 mm metal hard wire. If such a two-layer reinforcing layer is provided, sufficient pressure resistance and durability are provided. Can be obtained. When the reinforcing layer has a two-layer structure, it is preferable from the viewpoint of production and appearance that the organic fiber reinforcing layer is on the inner layer side and the metal hard wire reinforcing layer is on the outer layer side.

  As shown in FIG. 1, in the case of a hose having a structure having three rubber layers, all the rubber layers may be formed of the rubber composition of the present invention, and only one or only two layers of the present invention are present. However, as described above, it is preferable that at least an intermediate rubber layer which is likely to cause rubber breakage due to thinning is formed of at least the rubber composition of the present invention.

FIG. 1 shows an example of the configuration of a hose to which the present invention can be applied. The hose of the present invention is not limited to the illustrated one. For example, the following (1) to (3) It can be set as such a structure.
(1) Inner tube rubber layer / Reinforcement layer / Coating rubber layer
(2) Resin layer / Inner tube rubber layer / Reinforcement layer / Coating rubber layer
(3) Resin layer / Adhesive layer / Inner tube rubber layer / Reinforcement layer / Coating rubber layer

  Further, in the structure of FIG. 1, a resin layer as the innermost layer may be provided inside the inner tube rubber layer 1.

  The hose of the present invention can be effectively applied to various uses such as a water supply hot water supply hose, a refrigerant transport hose, an oil cooler hose, a hydraulic hose, a marine hose, and the like.

  Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples.

In addition, the short fiber used in the following Examples and Comparative Examples is as follows.
Polyketone fiber: In the general formula (I), R is ethylene, and in m-cresol,
A polymer having a degree of polymerization showing a solution viscosity of 4.0 dL / g measured at 60 ° C.
Polyketone fiber made of ton resin
Average fiber diameter 1.0μm
Average fiber length 5mm
Natural cellulose fiber: average fiber diameter 15μm
Average fiber length 2mm
Aromatic polyamide fiber: Average fiber diameter 10 μm
Average fiber length 3mm

These short fibers were subjected to the following RFL treatment.
[RFL]
Product name: Resorcin F (formalin): manufactured by Mitsui Chemicals, Inc. Product name: formalin L (latex): manufactured by Nippon Zeon Co., Ltd. Product name: VP latex 2518FS
L (latex): SBR manufactured by JSR Inc. Product name: JSR1500
(Latex is a mixture of 70 parts by weight of VP latex and 30 parts by weight of SBR)

Examples 1-3, Comparative Examples 1-4
About the rubber composition which mix | blends the short fiber shown in Table 1 in the quantity shown in Table 1 per 100 weight part of rubber components of a rubber composition, rubber skin, flow property, and a green modulus are investigated by the following method, and a result is shown in Table 1. Indicated.

In addition, the compounding composition other than the short fiber of a rubber composition is as follows.
[Composition composition of rubber composition]
Rubber component (NR (RSS # 4): NBR (JSR N230S)) = 60:40 (weight ratio): 100 parts by weight Carbon black (“Seast F” manufactured by Tokai Carbon Co.): 50 parts by weight Sulfur (manufactured by Tsurumi Chemical Co., Ltd.) "Zinc flower mixed sulfur"): 3.0 parts by weight Accelerator ("Noxeller CZ-G" manufactured by Ouchi Shinsei Chemical): 1.0 parts by weight

[Evaluation method]
<Rubber skin>
The smoothness of the extruded skin was examined visually and evaluated according to the following criteria.
◎: Very good ○: Good △: Normal ×: Poor <Flowability>
The flow properties at 100 ° C. and 150 ° C. were examined by a flow tester (measurement pressure: 50 kg / cm ² ).
<Green modulus>
A JIS No. 1 dumbbell was punched from a 2 mm thick sheet and examined with a Tensilon (tensile tester, tensile speed: 50 mm / min). The green modulus in the case of Comparative Example 1 was set as 100 and indicated as a relative value.

From Table 1, the following is clear.
That is, in Examples 1 to 3 blended with polyketone fibers, the flowability at 100 ° C., which is an extrusion temperature condition, is good without damaging the rubber skin by blending short fibers, while it is a vulcanization temperature condition. It can be seen that the flowability is low, and therefore rubber rise is prevented. Also, it can be seen that the green modulus is high and rubber breakage is prevented.

  On the other hand, with natural cellulose fibers, the green modulus can be increased by increasing the blending amount, but the flowability is impaired, the extrusion moldability is deteriorated, and the rubber skin is also deteriorated.

  In addition, with the aromatic polyamide fiber, good results are not obtained in any of rubber skin, flowability, and green modulus.

It is a perspective view which shows the structural example of a hose.

DESCRIPTION OF SYMBOLS 1 Inner tube rubber layer 2 Intermediate rubber layer 3 Outer rubber layer 4 1st reinforcement layer 5 2nd reinforcement layer

Claims (7)

A rubber composition for forming a rubber layer of a hose, comprising a polyketone fiber ,
The polyketone fiber is a short fiber having an average length of 0.1 to 50 mm,
The rubber composition for hoses, wherein the content of the polyketone fiber is 0.5 to 50 parts by weight with respect to 100 parts by weight of the rubber component . The rubber composition for a hose according to claim 1, wherein the polyketone fiber has an average fiber diameter of 1 to 1000 µm. According to claim 1 or 2, wherein the polyketone fibers rubber composition for a hose, which is a fiber of the polyketone resin represented by the following general formula (I).

(In the formula (I), R is a linking group derived from an ethylenically unsaturated compound, and each repeating unit may be the same or different.) 4. The rubber composition for hoses according to claim 3 , wherein R in the general formula (I) is a linking group derived from ethylene. 5. The degree of polymerization of the polyketone resin according to claim 3 or 4 , wherein the solution viscosity measured in m-cresol at 60 ° C. is in the range of 1.0 to 10.0 dL / g. Rubber composition for hose. A hose comprising a rubber layer made of the rubber composition for a hose according to any one of claims 1 to 5 . 7. The hose according to claim 6, wherein an inner tube rubber layer, an intermediate rubber layer, and an outer rubber layer are laminated between respective rubber layers via a reinforcing layer, and at least the intermediate rubber layer is formed from the rubber composition. A hose characterized by being made.

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