JP3077689B2 - Heat resistant hose - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-resistant hose suitable for transporting a high-temperature fluid, such as an air hose for an automobile, particularly an air hose for a supercharger, and an oil hose for an automobile requiring heat resistance.

[0002]

2. Description of the Related Art Conventional air hoses and oil hoses include, for example, nitrile rubber (hereinafter, also referred to as "NBR") on an inner tube of a hose and chloroprene rubber (hereinafter, "C") on an outer tube of the hose.
R "), or acrylic rubber (hereinafter also referred to as" ACM ") when heat resistance is particularly noted.

[0003] In recent years, as for an example of increasing the output of an engine in an automobile, there has been a demand for a supercharger air hose for a turbocharged vehicle to have a supercharger pressure of 0.15 MPa. Correspondingly, there have been cases where heat resistance such as, for example, durability of 150 ° C. for 10,000 hours is required for the hose inner tube. This is a very severe condition.

As an example of such a demand for a hose having a high heat resistance, an attempt has been made to use a fluorine rubber (hereinafter, also referred to as "FKM") for at least an inner tube of a heat resistant hose.

[0005]

However, a hose using NBR for the inner tube and CR for the outer tube or a hose using ACM cannot meet the severe heat resistance requirement. Further, when the high temperature fluid is oil such as engine oil, it is not possible to simultaneously satisfy high levels of heat resistance / oil resistance.

On the other hand, at least the F
Heat resistant hoses using KM are expensive. In addition, when used for a turbocharger air hose, part of the high-temperature exhaust gas containing engine oil particles is circulated to the turbocharger air hose due to the mechanism of the turbocharger. There is also a problem that FKM is deteriorated by a certain amine component, and it is also difficult to simultaneously satisfy a high level of heat resistance / oil resistance.

Further, a heat-resistant hose is often wound with a fiber reinforcement between the inner tube and the outer tube of the hose. Conventionally, a fiber reinforcement obtained by braiding a filament yarn having a smooth surface is often used. For this reason, there is a case where a yarn pull-out occurs due to insufficient joining force between the inner tube of the hose and the fiber reinforcing material, thereby impairing airtightness or liquid tightness. Such defects tend to appear more pronounced as the heat resistance requirements of the hose become more severe.

Accordingly, the present invention is to solve these problems.

[0009]

Means for Solving the Problems (Structure of the First Invention) According to the structure of the first invention (the invention described in claim 1) for solving the above-mentioned problems, at least the innermost layer of the hose is made of a fluororubber and an acrylic resin. A rubber blended with a rubber, wherein the blended rubber has a FKM: ACM = 2: 8-
The blended rubber has a blend ratio of 8: 2, and the blended rubber has an integrated value A × B of a nitrogen adsorption specific surface area value A (m ² / g) and a weight part value B of an addition amount of 3500 or less. A heat-resistant hose with black added.

(Structure of the Second Invention) In order to solve the above problems, the structure of the second invention (the invention according to claim 2) is that the blend rubber according to the first invention is characterized in that the fluororubber and the acrylic rubber are used. This is a heat-resistant hose that is a homogeneously dispersed blend rubber with a base rubber.

(Structure of Third Invention) The structure of the third invention (the invention described in claim 3) for solving the above-mentioned problem is the same as the structure of the fluororubber in the blend rubber according to the first invention or the second invention. The blend ratio on a weight basis with the acrylic rubber is FKM: ACM
= 3: 7 to 7: 3.

(Structure of the Fourth Invention) The structure of the fourth invention (the invention according to claim 4) for solving the above-mentioned problem is the hose end made of the blended rubber according to the first invention to the third invention. A yarn of the fiber reinforcement comprising at least one layer of a hose inner tube including an inner layer, a fiber reinforcement wound around the hose inner tube, and one or more layers of a hose outer tube joined thereto; A heat-resistant hose having a pull-out force of 1 N / mm or more.

(Structure of the Fifth Invention) The structure of the fifth invention (the invention as set forth in claim 5) for solving the above-mentioned problem is a hose comprising the blend rubber according to the first to third inventions. A hose inner tube having at least one layer including an inner layer, a fiber reinforcing material wound around the hose inner tube, and one or more hose outer tubes joined thereto; It is a heat-resistant hose constituted by using a yarn or a filament yarn having a number of twists of 100 turns / m or less.

(Structure of Sixth Invention) In order to solve the above-mentioned problems, the structure of the sixth invention (the invention described in claim 6) is that the heat-resistant hose according to the first invention to the fifth invention is a supercharger. It is a heat-resistant hose that is an air hose for use.

[0015]

(Function and Effect of First Invention) In the heat-resistant hose of the first invention, the blend ratio of the innermost layer of the hose on a weight basis is FKM: ACM = 2: 8 to 8:
2. A hose for transporting a high-temperature oil or a high-temperature gas containing oil particles because carbon black, which is made of a blend rubber of a fluoro rubber and an acrylic rubber, which is 2, and A × B is 3500 or less is added. However, the problem of the prior art can be solved by simultaneously satisfying a high level of heat / oil resistance.

There are scattered references that point out that a blended rubber of FKM and ACM generally has heat resistance. For example, 175 ° C./240 hours or 200 ° C./240 hours shown in Examples described later. Satisfaction of heat resistance under such severe conditions or satisfaction of oil resistance under conditions of 150 ° C./480 hours has not been confirmed so far, and the knowledge of the present invention makes the first invention possible. became. In addition, 200 ° C
/ 240 hours can be evaluated as a condition comparable to the heat-resistant condition of 150 ° C./10,000 hours.

Further, the heat-resistant hose of the first invention is less expensive than a heat-resistant hose in which the inner tube of the hose is made of only FKM, and is made of an amine component which is an additive of engine oil.
Deterioration of the KM component is also reduced.

(Function / Effect of Second Invention) In the heat-resistant hose of the second invention, since the blend rubber is composed of a homogeneously dispersed blend rubber, for example, the following Table 2
As shown in the above, particularly excellent heat / oil resistance can be satisfied at the same time.

(Action and Effect of Third Invention) In the heat-resistant hose of the third invention, the blend ratio of the blend rubber on a weight basis is FKM: ACM = 3: 7.
Since the ratio is 特 に 7: 3, particularly excellent heat / oil resistance can be simultaneously satisfied, for example, as shown in Table 2 below.

(Operation / Effect of the Fourth Invention) In the heat-resistant hose of the fourth invention, the first to third inventions are described.
In addition to the effects of the invention, the fiber pull-out force of the fiber reinforcement is 1 N / mm
Due to the above, even if the heat-resistant hose is used under severe heat-resistant conditions, there is a possibility that the yarn may be pulled out due to insufficient joining force between the hose inner tube and the fiber reinforcing material, thereby impairing the airtightness or liquid tightness. Less is.

(Function / Effect of the Fifth Invention) In the heat-resistant hose of the fifth invention, the first to third inventions are described.
In addition to the effects of the invention, since the fiber reinforcing material is formed by using a so-called fluffy spun yarn or a filament yarn having a twist of 100 turns / m or less, a heat-resistant hose is used under severe heat-resistant conditions. However, there is little possibility that the yarn may come off due to insufficient joining force between the inner tube of the hose and the fiber reinforcing material, and the airtightness or liquid tightness may be impaired.

(Function and Effect of Sixth Invention) According to the sixth invention, one of preferable uses of the heat-resistant hose according to the present invention is provided.

[0024]

[0025]

Next, embodiments of the first to seventh inventions will be described. In the following, the term “the present invention” simply refers to the first to seventh inventions collectively.

[Heat-Resistant Hose] In the present invention, the heat-resistant hose includes, without limitation, hoses used for transporting high-temperature fluids irrespective of gas or liquid.

Typical examples of the application are an air hose for a turbocharger, an EGR (exhaust gas recirculation device) hose, an engine oil cooler hose, an automatic transmission cooler hose, and the like used in automobiles. In particular, an air hose for a turbocharger is a preferred example of use. As is well known, a part of exhaust gas containing particles of engine oil is circulated at a high temperature in a supercharger air hose.

The heat-resistant hose of the first invention includes FKM and AC
A single-layer rubber tube using a blended rubber with M, at least one inner tube using a blended rubber of FKM and ACM for at least the innermost layer, and any material containing the same material was used. One that includes one or more layers of outer pipes, and one in which a fiber reinforcing material is wound between the inner pipes and the outer pipes, and includes a high-temperature oil or a high-temperature oil containing oil particles. It is intended for gas transport.
The above-described air hoses and oil hoses for a supercharger of an automobile are typical examples.

The heat-resistant hose of the second invention or the third invention has the following features.
It comprises a hose inner tube having at least one layer, a fiber reinforcing material wound around the hose inner tube, and one or more layers of a hose outer tube joined thereto. A blend rubber of FKM and ACM is used for at least the innermost layer of the hose. Here, the "hose innermost layer" refers to the hose inner tube when the hose inner tube has one layer, and refers to the innermost layer when the hose inner tube has two or more layers.

Such a blended rubber can be used for a layer other than the innermost layer in the inner tube of the hose and also in the outer tube of the hose.
Further, unlike the heat-resistant hose of the first invention, as long as the hose is used for transporting a high-temperature fluid, a hose not for transporting high-temperature oil or a high-temperature gas containing oil particles is also included without limitation.

[Blend Rubber] The blend rubber of the present invention is a blend of FKM and ACM. There is basically no limitation on the blend ratio between the two. However, FKM:
More preferably, the ACM weight ratio blend ratio is in the range of 2: 8 to 8: 2, particularly preferably in the range of 3: 7 to 7: 3.

The mode of blending FKM with ACM is not limited. For example, a so-called dry blend product,
Needless to say, a blended rubber obtained by mechanically kneading and blending unvulcanized FKM and ACM using a roll or the like and then vulcanizing is included. Further, the homodisperse blended rubber according to the fourth invention is particularly preferable. The homodisperse blended rubber refers to a blended rubber in which fluororubber and acrylic rubber are uniformly dispersed at the molecular level and are not phase-separated.

It is difficult to realize a homogeneously dispersed blend rubber by dry blending. For example, a latex blending method in which latex-like ACM and latex-like FKM are mixed and stirred and then co-coagulated, or FK is used.
M is dissolved or swelled in the acrylic monomer, and then the acrylic monomer is subjected to polymerization to be polymerized,
It can be obtained by a process in which a necessary filler and a crosslinking agent are contained for crosslinking.

[FKM] As the FKM used in the present invention, one or more kinds of known arbitrary ones can be selected and used. For example, vinylidene fluoride copolymers such as vinylidene fluoride / hexafluoropropylene, vinylidene fluoride / tetrafluoroethylene / hexafluoropropylene, and vinylidene fluoride / chlorotrifluoroethylene are particularly preferred. Tetrafluoroethylene / propylene, hexafluoropropylene / ethylene, fluoro (alkyl vinyl ether) (including those containing a plurality of ether bonds) / olefin copolymer, fluorosilicone rubber, fluorophosphazene rubber, etc. are also preferred. Can be used. FKM of the type which can be crosslinked with peroxides is also particularly preferred.

[ACM] The ACM used in the present invention is of any known type, for example, one or two of the following:
One or more kinds of polymers composed of at least two kinds of monomers can be selected and used. ACM of the type which can be crosslinked with peroxides is particularly preferred.

For example, acrylates such as methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, n-octyl acrylate, methoxymethyl acrylate, methoxyethyl acrylate, and ethoxyethyl acrylate, or methacrylate, vinyl acetate, and propion corresponding thereto. Vinyl esters such as vinyl acrylate and vinyl butyrate, vinyl ketones such as methyl vinyl ketone and ethyl vinyl ketone, styrene,
vinyl aromatic compounds such as α-methylstyrene and vinyltoluene; conjugated dienes such as butadiene and isoprene; α-monoolefins such as ethylene, propylene and 1-butene; and hydroxyl groups such as β-hydroxyethyl acrylate and 4-hydroxybutyl acrylate. And vinyl and vinylidene monomers having a nitrile group such as acrylonitrile, methacrylonitrile, and β-cyanoethyl acrylate.

The type of acrylic monomer used in preparing the homodisperse blend rubber may be arbitrarily selected. For example, n-butyl acrylate, ethyl acrylate, ethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, MMA ( Methyl methacrylate), EMA (ethyl methacrylate), B
MA (butyl methacrylate), HEMA (2-hydroxyethyl methacrylate), GMA (glycidyl methacrylate), MEMA (2-methoxyethyl methacrylate), MSPM (3- (trimethoxysilyl) propyl methacrylate), etc. One or more kinds of α-fluoroacrylate and the like can be arbitrarily selected and used.

[Fiber Reinforcing Material] The fiber reinforcing material of the second invention is formed by using a spun yarn or a filament yarn having a twist of 100 turns / m or less.

The term "spun yarn" as used herein refers to a yarn obtained by collecting and arranging a large number of staples (short fibers) and twisting them to form a yarn. Further, in order to improve the adhesiveness by the anchoring effect of the fluffing into the rubber, it is difficult for thread to come off with the hose tube forming material. Therefore, the joining force with the hose inner tube or the like is secured, and the airtightness and liquid tightness are improved.

The "filament yarn" is a bundle of a large number of filaments (filaments) and twisted into a yarn form. Generally, since there is no fluff, a material for forming a hose pipe is used. And slips easily between them. However, when the number of twists of the filament yarn is 100 turns / m or less, the yarn is deformed into a flat shape at the time of forming the hose.
It has been found that the rubber comes into close contact with the rubber with a large contact area, and therefore has the same effect of improving the adhesiveness as the spun yarn.

On the other hand, if the fiber reinforcing material which is unlikely to cause thread pull-out is expressed by parameters, it is desirable that the fiber pull-out force be 1 N / mm or more. Then, it was found that when the fiber reinforcing material was constituted by using the above-described spun yarn or the filament yarn having the number of twists of 100 turns / m or less, a yarn pulling force of 1 N / mm or more could be realized.

The material of the fiber reinforcing material is not limited, but the above-mentioned spun yarn or filament yarn made of an aromatic polyamide fiber having excellent heat resistance is preferred.

The material form (spun yarn / filament yarn) of these fiber reinforcing materials and the number of twists of the filament yarn are as follows.
This is one of the major factors that determine the sealing performance (airtight pressure) of a heat-resistant hose. In addition, the constituent materials of the inner tube and the outer tube of the heat-resistant hose also affect the hermetic pressure. In general, when the constituent material is only FKM, it is difficult to obtain a sufficient bonding force with the fiber reinforcing material, so that the hermetic pressure is low. , ACM and FKM-ACM blend rubber have a high hermetic pressure. Usually, the airtight pressure of the heat-resistant hose is desirably 0.15 MPa or more.

[Carbon Black] Heat-resistant hoses, including the heat-resistant hoses of the present invention, are generally made of hoses under severe heat-resistant conditions (for example, 200 ° C./240 hours) depending on the grade and amount of carbon black added thereto. It has been found by the present inventors that elongation is greatly affected.

That is, the nitrogen adsorption specific surface area of carbon black is defined as A (m ² / g), and the PHR of carbon black is determined.
Assuming that the addition amount based on (Per Handred Rubber) is B, it is preferable that the integrated value A × B is 3500 or less, particularly 3000 or less, because the decrease in hose elongation is effectively prevented.

[Other Additives] In addition to carbon black, the blended rubber of the present invention may contain various known additives such as vulcanizing agents, vulcanization accelerators, softeners, plasticizers, stabilizers and coloring agents. Can be optionally included.

[0047]

Next, an embodiment of the present invention will be described.

( Preparation of Test Pieces ) The vulcanized rubber test pieces were prepared according to Examples 1 to 5 shown in Table 1.
The kneaded composition (shown in parts by weight) shown in Comparative Example 1 and Comparative Example 2 was kneaded with an open roll, and vulcanized rubber test pieces were vulcanized under the following conditions. Was prepared. The vulcanization molding conditions of the vulcanized rubber test piece according to each example in Table 1 were as follows. It has been sulfurized.

[0049]

[Table 1]

Next, in Table 1, "show black N22"
“0” (trade name) is an ISAF grade carbon black manufactured by Showa Cabot Co., Ltd. having a nitrogen adsorption specific surface area of 111 m ² / g, and “Show Black N330” (trade name) is a Showa having a nitrogen adsorption specific surface area of 75 m ² / g. H made by Cabot
AF grade carbon black, "Seast SO" (trade name)
"Asahi Thermal" is a FEF-grade carbon black manufactured by Tokai Carbon Co., which has a nitrogen adsorption specific surface area of 42 m ² / g.
(Trade name) is FT grade carbon black manufactured by Asahi Carbon Co., having a nitrogen adsorption specific surface area of 24 m ² / g.

With respect to these carbon blacks added to the rubbers of the examples and comparative examples, the integrated values of the nitrogen adsorption specific surface area value A and the added parts by weight value B are shown in Table 1.
In the “A × B” column. Further, “Park Mill D” (trade name) in Table 1 is an organic peroxide (dicumyl peroxide) manufactured by NOF Corporation added as a crosslinking agent,
"TAIC" is triallyl isocyanurate added as a co-crosslinking agent.

( Evaluation of Test Pieces ) With respect to the test pieces according to Examples 1 to 5 and Comparative Examples 1 and 2 in Table 1, six types of evaluations including the following evaluations (1) to (6) were made. The test was performed.

Evaluation (1): Physical properties under normal conditions were evaluated according to JIS K6301. The evaluation items were "tensile strength",
"Elongation" and "hardness".

Evaluation (2): The heat aging resistance was evaluated under the conditions of 175 ° C./240 hours in accordance with JIS K6301 “air heating aging test”. The evaluation items are "tensile strength change rate", "elongation change rate", "hardness change", and "appearance". Of these, the appearance was evaluated using 18 test pieces after aging.
When the test piece was bent at 0 ° and there was no abnormality, the test piece was marked as “OK”, the test piece with cracks on the surface as “crack”, and the test piece with broken test piece as “Ore”.

Evaluation (3): The test condition was 200 ° C./24
The heat aging resistance was evaluated in the same manner as in evaluation (2) except that the time was 0 hour. Notation of evaluation items and results is also evaluated (2)
Is the same as

Evaluation (4): The engine oil resistance was evaluated under the conditions of 150 ° C./480 hours in accordance with immersion test of JIS K6301. The test liquid "Toyota Castle Diesel Oil New Special CD
10W-30 (trade name) ". The evaluation items are "tensile strength change rate", "elongation change rate", "hardness change", "volume change rate", and "appearance". The method of evaluating the appearance and the method of expressing the results are the same as those of the evaluation (2).

Evaluation (5): "Toyota Castle Diesel Oil New Special CD 10W-3" was used as a test solution in accordance with immersion test of JIS K6301.
Using "0", the engine oil resistance was evaluated under the conditions of 150 ° C / 480 hours. However, as a test method, a test piece was immersed in a test solution in a glass test tube, and the test tube was sealed in a cork stopper, held in an oil bath maintained at the test temperature, and vented through the cork stopper. The test was conducted while blowing / discharging air. The evaluation items are the same as evaluation (4) except for the volume change rate, and the appearance evaluation method and the result notation method are the same as evaluation (4).

Evaluation (6): The permanent compression strain was evaluated under the conditions of 175 ° C./72 hours in accordance with JIS K6301. Table 2 shows the evaluation results of the six types of tests (Evaluation (1) to Evaluation (6)) according to each Example and Comparative Example.

[0059]

[Table 2]

However, as understood from the comparison with Comparative Example 1, the integrated value A × B of the nitrogen adsorption specific surface area value of the added carbon black and the weight part (PHR) value B of the added amount.
Is more preferably 3500 or less. In the case of Example 6 in which this value exceeds 3500, 200 ° C./24
Under the heat aging condition of 0 hours, the decrease in the elongation of the test piece is larger than in the other examples.

From the evaluation results of Comparative Example 1 using Bomac D, it can be seen that ACM cannot be used particularly under a heat aging condition of 200 ° C./240 hours because of a large decrease in tensile strength and elongation.

Further, from the evaluation results of Comparative Example 2 using Daiel G801, FKM is excellent in heat aging resistance, but is inferior in engine oil resistance and oxidation-deterioration engine oil resistance, probably due to the effect of an engine oil additive. .
Then, it can be seen that the test piece after the test is in a state where a crack is formed when the test piece is bent, so that the test piece cannot be used.

(Preparation of Heat-Resistant Hose ) As shown in the column of “Specifications” in Tables 3 and 4, the rubber material according to each of the above Examples and Comparative Examples was replaced with an inner surface (hose inner tube) rubber material and an outer surface ( Hose outer tube) Hose Examples 1 to 6, and a hose in which a fiber reinforcing material using a spun yarn or a filament yarn made of a predetermined material is interposed in a joined state between rubber materials and between them. Comparative Examples 1 to Hose Heat-resistant hoses according to Comparative Example 4 were produced.

As a specific manufacturing method, first, an inner tube of a hose was extruded, a fiber reinforcing material was braided into the tube, and an outer tube of the hose was extruded and cut into a predetermined length. Then, after inserting a metal mandrel into this tube, it is heated at 160 ° C / 6 with steam.
The primary vulcanization was performed under the condition of 0 minutes, the mold was removed (extracted from the mandrel), and then the secondary vulcanization was performed with hot air in an oven at 150 ° C. for 8 hours.

As for “material of reinforcing yarn” in the column of “specifications”, “Conex (trade name) manufactured by Teijin, an aromatic polyamide”, and “Kevlar” (product manufactured by DuPont, an aromatic polyamide) are used. Name), is polyester,
Shown respectively.

The heat-resistant hose of each of these examples had a size of 53 mm in inner diameter and 63 mm in outer diameter assuming a normal air hose for a turbocharger. It can also be applied to hose evaluation.

( Evaluation of Heat-Resistant Hose) The burst pressure (MPa), pull-out force (N / mm), airtightness-leakage of the heat-resistant hoses of the respective hose examples and hose comparative examples were determined by the following test methods. Each item of pressure (MPa), heat aging resistance and engine oil resistance was evaluated.

That is, the burst pressure is JIS K6330 4.
2.1 (2).

The method for evaluating the reinforcing yarn pull-out force is as follows. For the heat-resistant hoses according to each of the hose examples and the hose comparative examples, only a predetermined area of the outer tube layer of the hose is cut and peeled off, and the fiber reinforcement exposed there is exposed. A hook or the like is hooked on one of the constituent yarns of the material, and the force required to pull out the yarn is measured.

Airtightness-Leak pressure is determined according to JIS K
The following method was used in accordance with 6330 421 (3) (a). That is, the heat-resistant hose according to each of the hose examples and the hose comparative examples is formed by forming a rigid mating pipe (inner diameter of 48 mm, outer diameter of 54 mm, outer periphery of the tip portion in a width of 4 mm and height of 1 mm in a mountain-shaped ridge in a ring shape). By doing so, the outer diameter 56
mm) of the heat-resistant hose with a ring-shaped clamp (HS32, manufactured by Sawahisa), and compression of 10% with respect to the initial thickness of the heat-resistant hose. Clamped with force. Then, by applying a gas pressure in water, the gas leakage pressure of the heat-resistant hose outer insertion portion was measured.

The heat aging resistance is determined by aging the heat resistant hose sample having a length of about 25 mm under the heat aging condition of 200 ° C./240 hours, and then leaving the sample at room temperature for 3 hours to 24 hours. The sample was rapidly compressed in the direction perpendicular to the plate surface until the inner diameter of the sample became 50% of the original, and it was evaluated whether or not an abnormality such as a crack or a crack occurred in the sample.

The engine oil resistance means that the above-mentioned heat-resistant hose sample having a length of about 25 mm whose one end is sealed is filled with engine oil (the above-mentioned Toyota Castle Diesel Oil New Special CD 10W-30) and then immediately drained and removed. While the operation was repeated every 24 hours, the sample with the engine oil removed was kept at 200 ° C./24
After aging under the heat aging condition of 0 hour, the occurrence of abnormalities was evaluated by the same method as the above-mentioned heat aging resistance test.

The evaluation results of these items are shown in Table 3 for Hose Example 1 to Hose Example 5, and Comparative Example 1 for Hose.
Table 4 shows Comparative Example 4 to Hose. From the results in Tables 3 and 4, the following points 1) to 3) are understood.

[0074]

[Table 3]

[0075]

[Table 4] 1) Regarding the pull-out force of the reinforcing yarn, the hose examples 1 to 5 using the spun yarn as the fiber reinforcing material and the hose comparative examples 2 and 3 all show 1.8 N / mm or more. Among these, the hose comparative example 3 using the DIAL G801 which is FKM as the inner tube-outer tube material of the heat-resistant hose has the lowest value as the relative evaluation.

2) 3 using filament yarn as fiber reinforcing material
As for the example, the pull-out force of the reinforcing yarn of the hose comparative example 1 was 0.4
Nm / mm, which is a remarkably low value, but the hose of Example 6 using a filament yarn having a twist of 100 turns / m, and Bomac D which is an ACM for the inner tube and the outer tube of the heat resistant hose.
In Comparative Example 2 where the number of twists of the filament yarn is relatively small, that is, 150 turns / m, a satisfactory reinforcing yarn pulling force is shown.

3) Hermeticity-Leak pressure also shows a result almost corresponding to the reinforcing yarn pulling force. Therefore, even when the spun yarn is used for the fiber reinforcement or the filament yarn is used for the fiber reinforcement, the twist number is 100 turns / m or less / ACM is used for the inner tube-outer tube material of the heat-resistant hose. It can be seen that the ones used exhibited satisfactory reinforcement thread pull-out force and airtightness-leakage pressure.

Regarding the evaluation results of the heat aging resistance, the hose comparative example 2 is remarkably poor, and the hose comparative example 3 also has some problems. Also, regarding the evaluation results of the engine oil resistance, the hose comparative examples 2 to 4 are poor.

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroyoshi Mori Komaki City, Aichi Pref., 3600, Gedai Kita-gai, Tokai Rubber Industry Co., Ltd. (56) References JP-A-5-117408 (JP, A) JP-A-1-159345 (JP, A) JP-A-3-59042 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16L 11/00 B32B 25/10 C08K 5/00 C08L 7 / 00 F16L 11/12

Claims (6)

(57) [Claims] At least the innermost layer of a hose is made of a blend rubber of fluoro rubber and acrylic rubber, and the blend rubber has a blend ratio of FKM: ACM = 2: 8 to 8: 2 on a weight basis. The blend rubber is added with carbon black having an integrated value A × B of the nitrogen adsorption specific surface area value A (m ² / g) and the added part by weight value B of 3500 or less. hose. 2. The heat-resistant hose according to claim 1, wherein the blend rubber is a homogeneously dispersed blend rubber of the fluoro rubber and the acrylic rubber. 3. The blend ratio of the fluororubber and the acrylic rubber in the blended rubber on a weight basis is FKM: ACM = 3: 7 to 7: 3. Item 3. A heat-resistant hose according to any one of Items 2. 4. One or more layers of a hose inner tube including an innermost layer of a hose made of the blended rubber, a fiber reinforcing material wound around the hose inner tube, and one or more layers of a hose joined thereto. The heat-resistant hose according to any one of claims 1 to 3, further comprising an outer tube, wherein the fiber pull-out force of the fiber reinforcement is 1 N / mm or more. 5. One or more layers of a hose inner tube including an innermost layer of a hose made of the blended rubber, a fiber reinforcing material wound around the hose inner tube, and one or more layers of a hose joined thereto. 4. An outer tube, wherein the fiber reinforcing material is formed using a spun yarn or a filament yarn having a twist number of 100 turns / m or less. Heat-resistant hose. 6. The heat-resistant hose according to claim 1, wherein the heat-resistant hose is a supercharger air hose.