JP2000213670A - Fiber-reinforced hose - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure various kinds of performance such as heat resistance, oilproofness, and a sealing characteristic by using epoxy group containing acrylic rubber as acrylic rubber and mixing a vulcanizing composition partially including a thiourea compound in the acrylic rubber. SOLUTION: Acrylic rubber constituting an inside rubber layer and/or an outside rubber layer in a fiber-reinforced layer is epoxy group containing acrylic rubber, and a vulcanizing composition partially containing a thiourea compound is mixed with the acrylic rubber. Desirably, carbon black is also mixed with the acrylic rubber. The acrylic rubber containing an epoxy group as a cross- linking seat is prepared by copolymerization of a cross-linking seat monomer containing an epoxy group and at least one kind of monomer copolymerizable with the cross-linking seat monomer through a polymerizing method such as emulsion polymerization, suspension polymerization and solution polymerization. In addition to the thiourea compound, a vulcanizer such as an imidazole compound and/or a vulcanization accelerator such as quaternary ammonium salt are/is preferably mixed in the vulcanizing compound applied to the acrylic rubber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiber reinforced hose provided with a fiber reinforced layer between an inner rubber layer and an outer rubber layer and integrally vulcanized and formed.

[0002]

2. Description of the Related Art Conventionally, various performances such as heat resistance, oil resistance, pressure resistance, and sealability are required for oil hoses and air hoses for automobiles. As can be seen in the publication, at least one of the inner rubber layer and the outer rubber layer is made of an acrylic rubber material having excellent heat resistance and oil resistance, and between the inner rubber layer and the outer rubber layer. By providing a fiber reinforcement layer using aramid-based reinforcement yarn with excellent heat resistance, chemical resistance, and strength,
These are integrally vulcanized.

[0003] Aramid-based reinforcing yarns are very expensive and increase the production cost of hoses. Therefore, reinforcing yarns that can be used at lower cost (typically, polyester reinforcing yarns and polyamide reinforcing yarns). ) Is generally required to form the fiber reinforcement layer.

[0004]

However, unlike aramid reinforcing yarns, polyester reinforcing yarns and polyamide reinforcing yarns are easily deteriorated by heat, oil or a specific vulcanizing agent. Therefore, when providing a fiber reinforcing layer of a polyester reinforcing yarn or a polyamide reinforcing yarn, it is necessary to take sufficient measures against deterioration, and this measure impairs the physical properties of the acrylic rubber and the favorable vulcanization adhesion of the hose on the other side. It must not be.

For example, in the invention of "fiber reinforced rubber hose" disclosed in Japanese Patent Application Laid-Open No. Hei 10-205660, a fiber reinforced layer made of polyester reinforcing yarn is provided, and at least one of the inner rubber layer and the outer rubber layer is crosslinked with a carboxyl group. It is composed of a seat-containing acrylic elastomer and contains a polyvalent amine as a vulcanizing agent.

[0006] However, the carboxyl group, which is a cross-linking site of the acrylic elastomer, causes heat resistance of the polyester reinforcing yarn,
It is not always preferable from the viewpoint of preventing oil resistance deterioration and the like, and there is a possibility that the hose may have insufficient pressure resistance due to deterioration of the fiber reinforcement layer.

On the other hand, in the invention of "Elastomer composition and rubber hose" disclosed in Japanese Patent Application Laid-Open No. 9-227749,
A thiourea compound, an imidazole compound, a quaternary ammonium salt, etc. are blended with the epoxy group-containing acrylic rubber in order to give the acrylic rubber excellent extrusion processability and tensile strength, but not for fiber-reinforced hoses. ,
Therefore, no mention is made of any measures against deterioration of the reinforcing yarn.

Accordingly, the present invention provides an integrated measure for optimizing the vulcanization compound and the cross-linking of the acrylic rubber, thereby preventing the fiber reinforcing layer from deteriorating and improving the physical properties of the acrylic rubber and the vulcanization adhesion. Heat resistance and oil resistance of fiber reinforced hose with polyester fiber reinforced layer
An issue to be solved is to ensure various performances such as pressure resistance and sealability.

[0009]

Means for Solving the Problems The structure of the first invention of the present application (the invention of claim 1) for solving the above-mentioned problems is that the inner rubber layer at least one of which is made of acrylic rubber In a fiber reinforced hose provided with a fiber reinforced layer of a polyester reinforcing yarn or a polyamide reinforcing yarn between the outer rubber layer and the vulcanization molding, the acrylic rubber is an epoxy group-containing acrylic rubber, and It is a fiber-reinforced hose in which a vulcanized compound partially containing a thiourea compound is compounded.

(Structure of the Second Invention) The structure of the second invention (the invention described in claim 2) for solving the above-mentioned problem is as follows.
A fiber-reinforced hose, wherein the compounding amount of the thiourea compound in the vulcanized compound according to the first invention is 0.05 to 1.5 parts by weight based on 100 parts by weight of the acrylic rubber.

(Structure of Third Invention) The structure of the third invention of the present application (the invention according to claim 3) for solving the above problems is as follows.
A fiber-reinforced hose, wherein the thiourea compound according to the first or second invention is trimethylthiourea.

(Structure of the Fourth Invention) The structure of the fourth invention (the invention according to claim 4) for solving the above problems is as follows.
The fiber reinforced hose according to any one of the first to third inventions, wherein the vulcanized compound comprises the thiourea compound and an appropriate amount of an imidazole compound and a quaternary ammonium salt, respectively.

(Structure of the Fifth Invention) The structure of the fifth invention (the invention described in claim 5) for solving the above problems is as follows.
The fiber reinforced hose according to any one of the first to fourth inventions, wherein the acrylic rubber has an epoxy group content of 0.7 to 2.3% by weight.

(Structure of Sixth Invention) The structure of the sixth invention of the present application (the invention according to claim 6) for solving the above problems is as follows.
In the first to fifth inventions, the acrylic rubber is a fiber-reinforced hose having a monomer composition in which ethyl acrylate is 60% by weight or more.

(Structure of Seventh Invention) The structure of the seventh invention (the invention according to claim 7) for solving the above problems is as follows.
The fiber reinforced hose according to any one of the first to sixth inventions, wherein the carbon black compounded in the acrylic rubber has an average particle diameter of 30 to 75 nm.

(Structure of Eighth Invention) The structure of an eighth invention (an invention according to claim 8) for solving the above problems is as follows.
A fiber-reinforced hose, wherein the content of the carboxyl group end group contained in the polyester reinforcing yarn according to the first to seventh inventions is 20 equivalents / ton or less.

[0017]

(Actions and effects of the first invention) In the first invention, since an acrylic rubber containing an epoxy group is used as the acrylic rubber, when an acrylic elastomer containing a carboxyl group crosslinked site is used as in the above-mentioned prior art, In comparison, a vulcanizing agent (an imidazole compound or the like) which causes less deterioration of the polyester reinforcing yarn or the polyamide reinforcing yarn can be used, which is preferable for preventing deterioration of the polyester reinforcing yarn.

Even if the polyester (or polyamide) fiber reinforcing layer, which is susceptible to deterioration, inevitably deteriorates to some extent, the vulcanized acrylic rubber contains a thiourea compound in a part of the vulcanization-based compound. It exhibits normal physical properties (especially compression set) that can effectively cover the deterioration of the reinforcing layer, and can ensure the sealing properties of the hose at the joint with a metal pipe or the like.

(Function / Effect of the Second Invention) When an excessive amount (for example, 2 parts by weight or more) of a thiourea compound is blended, it does not show a degrading effect on aromatic polyamide reinforcing yarns such as aramid, but polyester reinforcing yarns. It has been found that the deterioration of polyamide and yarn is accelerated. However, in the second invention, such inconvenience can be avoided by setting the compounding amount of the thiourea compound to 1.5 parts by weight or less in combination with another vulcanizing compound.

The compounding amount of the thiourea compound in the vulcanized compound is 0.05 to 100 parts by weight of the acrylic rubber.
When the amount is less than the weight part, it is not always preferable to prevent an excessive compression set of the acrylic rubber.

(Function / Effect of Third Invention) In the third invention, since trimethylthiourea is used as the thiourea compound, the effect of the thiourea compound in the first invention or the second invention can be obtained most preferably.

(Action / Effect of the Fourth Invention) The type of the other vulcanizing agent and vulcanization accelerator used together with the thiourea compound as the vulcanizing compound of the present invention is not so limited. Appropriate amounts of an imidazole compound as a vulcanizing agent and a quaternary ammonium salt as a vulcanization accelerator (for example, 0.1 to 3 parts by weight of the former and 0.1 to 3 parts by weight of the latter based on 100 parts by weight of acrylic rubber) As a result, it is possible to avoid excessive use of the thiourea compound, and to obtain an effect of giving the acrylic rubber proper physical properties and reducing compression set.

(Function / Effect of the Fifth Invention) In the fifth invention, since the epoxy group content of the acrylic rubber is 0.7% by weight or more, it is possible to give the acrylic rubber proper physical properties and permanent compression set. it can. Further, since the epoxy group content of the acrylic rubber is set to 2.3% by weight or less, it is possible to prevent the extrudability and the like from being deteriorated due to excessive cross-linking sites.

(Function / Effect of the Sixth Invention) In the sixth invention, the acrylic rubber contains 60% by weight of ethyl acrylate.
Since it has the above monomer composition, the volume change of the acrylic rubber layer due to contact or immersion with oil such as engine oil is small, and therefore, the transfer of the vulcanizing agent in the acrylic rubber to the reinforcing yarn layer can be reduced, so that the reinforcement is performed. Deterioration of the yarn can be reduced.

(Function / Effect of the Seventh Invention) In the seventh invention, since the average particle diameter of carbon black to be mixed with the acrylic rubber is 30 to 75 nm, the average particle diameter is too small (for example, less than 30 nm). And good extrusion processability of the inner / outer rubber layers in the fiber reinforced hose can be ensured.

(Function / Effect of the Eighth Invention) In the eighth invention, since the fiber reinforcing layer is constituted by using a polyester reinforcing yarn having a carboxyl group terminal group content of 20 equivalents / ton or less, the fiber reinforcement The pressure resistance of the hose can be secured. It is presumed that the reason for this is that by reducing the amount of the carboxyl group end group, deterioration of the reinforcing yarn due to the thiourea compound in the vulcanized compound can be prevented.

[0027]

Next, embodiments of the first to eighth inventions will be described. In the following, simply "the present invention"
When it says, it points out 1st invention-8th invention collectively.

[Fiber Reinforced Hose] The fiber reinforced hose of the present invention is provided with a fiber reinforced layer of a polyester reinforcing yarn or a polyamide reinforcing yarn between an inner rubber layer and an outer rubber layer, and is integrally vulcanized and formed. One or both of the inner rubber layer and the outer rubber layer are made of acrylic rubber.

The inner rubber layer may constitute the innermost layer of the fiber reinforced hose, or the innermost layer of another material such as rubber may be formed further inside the inner rubber layer. or,
The outer rubber layer may constitute the outermost layer of the fiber reinforced hose, or the outermost layer of another material may be formed further outside the outer rubber layer.

Although the use of the fiber reinforced hose is not limited,
In particular, applications requiring performance such as heat resistance, oil resistance, pressure resistance, and sealability, such as oil hoses for automobiles, radiator hoses, oil hoses for cooling pipes of automatic transmission oil, and oil hoses for cooling pipes of engine oil. And an air hose.

[Acrylic Rubber] The acrylic rubber constituting the inner rubber layer and / or the outer rubber layer of the fiber reinforcing layer contains an epoxy group as a crosslinking site. On the other hand, at least one copolymerizable monomer is copolymerized by a known method such as emulsion polymerization, suspension polymerization, solution polymerization, or bulk polymerization.

Examples of the crosslinkable monomer include glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, and methallyl glycidyl ether. From the reason described above as the function and effect of the fifth invention, it is preferable to copolymerize these cross-linking monomers at a ratio such that the epoxy group content of the acrylic rubber is 0.7 to 2.3% by weight.

The main components of the monomer copolymerizable with the crosslinkable monomer include various known alkyl acrylates such as methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate and isobutyl acrylate; Various known alkoxyalkyl acrylates such as -methoxyethyl acrylate, 2- (n-propoxy) ethyl acrylate, 2- (n-butoxy) ethyl acrylate, and 3-methoxypropyl acrylate are exemplified.

The reason that the acrylic rubber has a monomer composition in which ethyl acrylate is 60% by weight or more, as in the sixth invention, has the above-mentioned effect and effect of reducing the deterioration of the reinforcing yarn. Is preferred.

Other components copolymerizable with the crosslinkable monomer include 1,1-dihydroperfluoroethyl (meth) acrylate, 1,1-dihydroperfluoropropyl (meth) acrylate, 1,1,5-triethyl Various known fluorine-containing acrylates such as hydroperfluorohexyl (meth) acrylate, 1-hydroxypropyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and hydroxyethyl (meth)
Various known hydroxyl-containing acrylates such as acrylates, diethylaminoethyl (meth) acrylate,
In addition to various known tertiary amino group-containing acrylates such as dibutylaminoethyl (meth) acrylate, and various known methacrylates such as methyl methacrylate and octyl methacrylate, various known alkyl vinyl ketones, vinyl ethers, allyl ethers, Examples thereof include a vinyl aromatic compound, vinyl nitrile, ethylene, propylene, vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, vinyl acetate, vinyl propionate, and alkyl fumarate.

Examples of the acrylic rubber used in the present invention are listed by brand name, for example, Knoxtite brand name manufactured by Nippon Mektron, Nipol AR brand name manufactured by Zeon Corporation, Toaaclon brand name manufactured by Toa Paint Co., Ltd. Denka ER (trade name, manufactured by Denki Kagaku Kogyo Co., Ltd.), RV series (trade name, manufactured by Nissin Chemical Co., Ltd.), Esplen EMA (trade name, manufactured by Sumitomo Chemical Co., Ltd.), JSR-AR and AREX (trade names, manufactured by Japan Synthetic Rubber Co., Ltd.) be able to.

[Vulcanizing Compound] The vulcanizing compound applied to the acrylic rubber comprises a thiourea compound and another vulcanizing agent and / or vulcanization accelerator used in combination therewith.

As the thiourea compound, for example, various thiourea compounds such as trimethylthiourea, ethylenethiourea, N, N'-diphenylthiourea, diorthotolylthiourea, diethylthiourea, dibutylthiourea, and dilaurylthiourea can be used. In particular, trimethylthiourea has a great effect of improving the compression set of acrylic rubber.

In order to obtain sufficient vulcanization adhesiveness while avoiding excessive blending of the thiourea compound, the vulcanization-based compound includes:
It is preferable to add an appropriate amount of a vulcanizing agent and / or a vulcanization accelerator in addition to the thiourea compound. The type of such a vulcanizing agent or vulcanization accelerator is not particularly limited. For example, it is preferable to use an imidazole compound as a vulcanizing agent and a quaternary ammonium salt as a vulcanizing accelerator. In that case, the imidazole compound is 0.2 to 3 parts by weight, and the quaternary ammonium salt is 0.1 to 100 parts by weight of the acrylic rubber.
It is preferable to mix 1 to 3 parts by weight.

As the above-mentioned imidazole compound, those in which an arbitrary atom or atomic group is substituted at each substitution position in the imidazole skeleton can be used arbitrarily. For example, 1-methylimidazole, 1,2-dimethylimidazole , 1-benzyl-2-ethylimidazole, 1-
Benzyl-2-phenylimidazole trimellitate, 1-aminoethyl-2-methylimidazole, 1-
Cyanoethyl-2-ethyl-4-methylimidazole and its trimellitate, 2,4-diamino-6
[2′-Methylimidazolyl- (1) ′] ethyl-s-
Triazine / isocyanuric acid adduct, N, N′-bis (2-methylimidazolyl-1-ethyl) urea,
N '-[2-methylimidazolyl- (1) -ethyl] adipoyldiamide, 1-dodecyl-2-methyl-3-benzylimidazolium chloride and the like can be mentioned.

As the quaternary ammonium salt, any one can be used. For example, tetraethylammonium bromide, tetrabutylammonium chloride, cetyltrimethylammonium bromide, n
-Dodecyltrimethylammonium bromide, cetylpyridium chloride, 1,8-diaza-bicyclo (5,4,0) undecene-7-benzylammonium chloride, cetylpyridium iodide and the like.

[Carbon Black] It is also preferable to mix carbon black with the acrylic rubber. However, carbon black having an average particle diameter (a value represented by a length average particle diameter measured by an electron microscope method) of less than 30 nm may be accompanied by a problem that the extrudability of rubber is deteriorated.
Those having an average particle diameter of at least nm are preferred. On the other hand, if the average particle diameter exceeds 75 nm, it may not be preferable in terms of deterioration of physical properties in normal state and deterioration of extrusion processability.

When the preferred carbon black is represented by a trade name, there can be mentioned Seast 116, Seast SO and Seast S manufactured by Tokai Carbon Co., Ltd. The amount of these carbon blacks is not particularly limited, but is preferably 30 to 100 parts by weight based on 100 parts by weight of the acrylic rubber.

[Fiber Reinforcement Layer] The fiber reinforcement layer is made of a polyester reinforcing yarn or a polyamide reinforcing yarn. The type and denier of the polyester reinforcing yarn or polyamide reinforcing yarn are not limited. The fiber reinforcing layer may be formed by winding these reinforcing yarns in a blade or spirally.In the case of spiral winding, a single or double reverse spiral winding or an intermediate between the double spiral winding. Embodiments such as those in which a rubber layer is interposed can be arbitrarily adopted.

As the polyester reinforcing yarn, one using a polyester having a carboxyl group terminal group content of not more than 20 equivalents / ton is the effect of the eighth invention.
It is preferable for the reason described in the effect section.

[0046]

EXAMPLES [Example 1] ( Preparation of acrylic rubber composition ) Table 1 at the end ("n" in the table)
"-BA" is n-butyl acrylate, "EA" is ethyl acrylate, and the unit of the numerical value in the table is% by weight.)
Examples 1-1 to 1-7 in Table 2 at the end and Comparative Example 1 in Table 3 at the end for F to 100 parts by weight, respectively.
As shown in each example of -1 to 1-6, the compound was added and kneaded by adding (the units of the numerical values in the table are all parts by weight) to obtain acrylic rubber compositions according to each example.

In Tables 2 and 3, "Seast 11
Each of "6" to "Seast 6" is a carbon black manufactured by Tokai Carbon Co., Ltd., and has an average particle diameter of 38 nm for Seast 116, 43 nm for Seast SO, 66 nm for Seast S, and 22 nm for Seast 6. "Asahi Thermal" is carbon black manufactured by Asahi Carbon Co., Ltd., and has an average particle size of 80 nm.

As shown in Tables 2 and 3, in each example, 0.5 parts by weight of the imidazole compound (1,2 dimethylimidazole) and 0.5 parts by weight of the quaternary ammonium salt (octadecyltrimethylammonium bromide). Except for Comparative Example 1-1, the thiourea compound (trimethylthiourea) was blended in parts by weight as shown in the table.

( Extrusion processability ) The extrusion processability of the acrylic rubber composition was evaluated by the Garvey die evaluation after subjecting unvulcanized rubber to heat aging at 40 ° C for 72 hours in accordance with ASTM D2230. went. The notation of “edge” in Tables 2 and 3 represents the appearance (sharpness and continuity) of the edge portion of the extruded product by the Garvey die.
The numerical values in the columns represent values of 10-level evaluation from 1 (poor) to 10 (excellent). The notation “surface skin” in Tables 2 and 3 indicates the smoothness of the surface skin, and the letters “A to E” in the “surface skin” column are five levels from A (excellent) to E (poor). Indicates a symbol for evaluation.

( Physical Properties ) Using the acrylic rubber composition according to each example, an unvulcanized rubber sheet having a thickness of 2 mm was produced by a 6-inch mixing roll, and after press vulcanization at 160 ° C. × 60 minutes, The sample was subjected to oven vulcanization at 150 ° C. for 8 hours to obtain a rubber test piece for evaluating physical properties in a normal state.

For these rubber test pieces, JIS K6
301, tensile strength (MP
a), elongation (%), hardness (JIS-A) and 150 ° C
The compression set under the condition of × 72 hours was evaluated. Tables 2 and 3 show the results.

( Oil resistance ) The rubber test piece according to each of the above examples was
The volume change rate (%) when immersed in a commercially available automatic transmission oil at 150 ° C. for 72 hours was determined according to JIS K6301.
It measured according to. Tables 2 and 3 show the results.

( Polyester Fiber Deterioration-1 ) A polyester fiber having a carboxyl group end group amount of 35 equivalents / ton, 1500 denier, and a tensile strength of 115 N
/ A 30 mm long polyester reinforcing yarn (polyester fiber-1) sandwiched between two unvulcanized rubber sheets according to each example having a thickness of 2 mm produced by the same means as described above, After press vulcanization of these laminates at 160 ° C. × 60 minutes, they were subjected to oven vulcanization at 150 ° C. × 8 hours, and the following measurements were performed.

A) Untreated: polyester fiber-1 was taken out of the laminate after oven vulcanization, and was subjected to JIS L10
The tensile strength was measured according to No.17. The measurement results are shown as a strength reduction rate (negative percentage) with respect to the original strength (115 N) in the column of “untreated” in “Polyester fiber-1 degradability” in Tables 2 and 3.

B) After air aging: After the oven-vulcanized laminate was air-aged at 150 ° C. for 240 hours, the tensile strength of polyester fiber-1 was measured in the same manner as in a) above. The measurement results are shown in the column of "Aging" in Tables 2 and 3.

C) After immersion in oil: The oven-vulcanized laminate was immersed in a commercial automatic transmission oil at 150 ° C. for 240 hours, and the polyester fiber-1 was obtained in the same manner as in a) above. Was measured for the tensile strength, and the measurement results were shown in the column of “immersion in oil” in Tables 2 and 3.

( Polyester Fiber Deterioration-2 ) A polyester fiber having a carboxyl group end group content of 15 equivalents / ton, 1500 denier, and a tensile strength of 130N.
/ Using a 30 mm long polyester reinforcing yarn (polyester fiber-2), a laminate was formed and vulcanized in the same manner as the above-mentioned "Polyester fiber degradability-1".
The same measurements a) to c) were performed as described above, and the measurement results are shown in the corresponding columns in “Polyester Fiber-2 Degradability” in Tables 2 and 3.

( Polyamide fiber deteriorating property ) It is made of polyamide fiber, has a denier of 1260 and a tensile strength of 116N.
/ Using a polyamide reinforcing yarn having a length of 30 mm, which is a strand, forming a laminate in the same manner as in the above “Polyester fiber degradability -1” and vulcanizing the same, and then measuring the same a) to c) as above And the measurement results are shown in the corresponding columns in “Polyamide fiber deterioration” in Tables 2 and 3.

( Evaluation Results of Each Example According to the First Embodiment )
In each of the examples according to the examples, the examples 1-1 to 1-7 include:
All of the evaluation items were satisfactory.

On the other hand, Comparative Example 1-1 in which the thiourea compound was not added to the acrylic rubber composition was inferior in compression set. Comparative Example 1-2 in which the amount of the thiourea compound was too large was inferior in extrusion processability, polyester fiber deterioration property, and polyamide fiber deterioration property. In Comparative Example 1-3 in which the average particle size of the carbon black was too small, the extrusion processability was poor (presumably due to an increase in viscosity due to gelation of the composition), and the compression set was inferior. Comparative Example 1-4 in which the average particle size of the carbon black is too large,
The extrudability was poor and the tensile strength of the rubber specimen was insufficient. In Comparative Example 1-5, in which the epoxy group content of the acrylic rubber was too small, the compression set was inferior. Comparative Example 1-6, in which the epoxy group content of the acrylic rubber was too large,
Extrudability was poor.

Further, in each of the examples according to the first embodiment, compared to polyester fiber-1, polyester fiber-2
In each of the evaluations "b) after air aging" and "c) after immersion in oil", the decrease in strength was small.

[Second Embodiment] ( Preparation of Fiber Reinforced Hose ) Polyester was placed between the inner rubber layer (inner rubber) as the innermost layer of the hose and the outer rubber layer (outer rubber) as the outermost layer of the hose. The fiber reinforced hose of the reinforcement yarn (the polyester fiber-1 or the polyester fiber-2) was provided to produce a fiber reinforced hose integrally vulcanized.

At this time, Examples 2-1 to 2-1 shown in Table 4 at the end were used.
For each of 2-4 and Comparative Examples 2-1 to 2-3, the inner surface rubber using the material shown in Table 4 was extruded to a thickness of 2.0 mm by an extruder, and then the polyester reinforcement shown in Table 4 was obtained. The yarn was braided to form a fiber reinforcing layer, and the outer rubber shown in Table 4 was extruded thereon to a thickness of 1.5 mm.
The unvulcanized fiber reinforced hose according to each of these examples had an inner diameter of 7.0 mm and an outer diameter of 14.5 mm.

After inserting the unvulcanized hose according to each example into an iron mandrel, the uncured hose was heated to 160 ° C. in a steam vulcanizer.
After steam vulcanization for 60 minutes and further withdrawing from the mandrel, hot air vulcanization was performed at 150 ° C for 8 hours in a gear oven to obtain fiber reinforced hoses according to each example.

( Extrusion processability ) The outer rubber layer surface of the vulcanized fiber reinforced hose according to each example was observed, and the surface having a smooth surface was represented by “○”, and the surface having a rough surface was represented by “×”. The evaluation was made and described in the column of “extruded skin” in Table 4.

( Hose Burst Pressure ) As shown in FIG. 1, one end of a fiber reinforced hose 1 according to each example was closed with a pipe 2 closed.
The other end is connected to a hydraulic pump 3 and these ends of the fiber reinforced hose 1 are clamped by a clamp jig 4.
The pressure increase speed is 0.98 to 1.96 under tight tightening.
MPa / min. An initial burst test was performed by operating a hydraulic pump at. In addition, a commercially available ATF (Toyota Castle Auto Fluid DII) is sealed in the fiber reinforced hose according to each example, and 150 ° C. × 2 in an oven.
After heat aging for 40 hours, the same rupture test (burst test after aging) was performed.

The evaluation results are shown in the column of "burst pressure" in Table 4. In practice, the burst pressure in the burst test after aging was 6MP.
It is considered that a value not less than a is a desirable target value.

( Hose Sealability ) A steel pipe with a Sn-Zn plating on the surface was inserted into one end of the fiber reinforced hose according to each example and tightened and fixed using a clamp jig.
0.6 MPa / min. From the other end by a hydraulic pump. The initial sealing pressure was measured by increasing the pressure at the following speed.
In the same manner as in the above burst pressure test, a commercially available ATF was sealed and heat-aged in an oven, and thereafter, the same sealing pressure measurement (sealing property after aging) was performed.

The evaluation results are shown in the column of "Sealability" in Table 4. In practice, it is considered that the measured target pressure after aging is preferably 2 MPa or more as a desirable target value.

( Evaluation Results of Each Example According to the Second Embodiment ) Second
In each example according to the examples, Examples 2-1 to 2-4
Both burst pressure and sealability were satisfied. Among them, Example 2-2 using polyester fiber-2 is:
Compared with Example 2-1 using polyester fiber-1, almost no decrease in burst pressure after aging was observed.

On the other hand, Comparative Example 1 having a poor compression set
Comparative Example 2-1 using -1 material was satisfactory in extrusion processability and burst pressure, but was inferior in sealability after aging.
Comparative Example 1-2 with poor extrusion processability Comparative Example 2-2 using material
Is inferior in extrusion processability, and inferior in burst pressure after aging due to deterioration of the fiber reinforcing layer using polyester fiber-1,
In addition, the sealing property after aging was slightly inferior due to the deterioration of the fiber reinforcing layer. Comparative example 1 having poor extrusion processability and compression set
Comparative Example 2-3 using the three materials was inferior in extrudability and sealability after aging.

[0072]

[Table 1]

[0073]

[Table 2]

[0074]

[Table 3]

[0075]

[Table 4]

[Brief description of the drawings]

FIG. 1 is a diagram showing a procedure for conducting a burst test according to an example.

[Explanation of symbols]

 1 Fiber reinforced hose 3 Water pressure pump

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 5/3445 C08K 5/3445 5/405 5/405 C08L 33/14 C08L 33/14

Claims (8)

[Claims] 1. A fiber-reinforced hose integrally vulcanized by providing a fiber-reinforced layer of polyester or polyamide reinforcing yarn between an inner rubber layer and an outer rubber layer at least one of which is made of acrylic rubber, A fiber reinforced hose, wherein the acrylic rubber is an epoxy group-containing acrylic rubber, and a vulcanized compound partially containing a thiourea compound is compounded therein. 2. The fiber according to claim 1, wherein the compounding amount of the thiourea compound in the vulcanized compound is 0.05 to 1.5 parts by weight based on 100 parts by weight of the acrylic rubber. Reinforced hose. 3. The fiber reinforced hose according to claim 1, wherein the thiourea compound is trimethylthiourea. 4. The fiber reinforcement according to claim 1, wherein the vulcanization-based compound comprises the thiourea compound and an appropriate amount of an imidazole compound and a quaternary ammonium salt, respectively. hose. 5. An acrylic rubber having an epoxy group content of 0.7 to 2.3% by weight.
The fiber reinforced hose according to claim 4. 6. The fiber reinforced hose according to claim 1, wherein the acrylic rubber has a monomer composition in which ethyl acrylate is 60% by weight or more. 7. The fiber reinforced hose according to claim 1, wherein an average particle diameter of carbon black compounded in the acrylic rubber is 30 to 75 nm. 8. The fiber reinforced hose according to claim 1, wherein the content of the carboxyl group end group contained in the polyester reinforcing yarn is 20 equivalents / ton or less.