JP2002181249A - Hose - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lightweight and low-cost hose. SOLUTION: The hose has laminated structure of a rubber layer 2 and a metal layer 1. The essential components of the rubber layer 2 are (A)-(D) described as follows: (A) rubber made of at least one of ternary copolymer of ethylene-propylene-diene and copolymer of ethylene-propylene; (B) peroxide vulcanizing agent; (C) resolcinol-based compound; and (D) melamine resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to hoses, and more particularly, to gasoline fuel hoses, hoses for fuel cell vehicles (methanol fuel hoses, hydrogen fuel hoses), engine cooling system hoses (radiator hoses, heater hoses, etc.), The present invention relates to an automotive hose such as a refrigerant transfer hose for a cooler.

[0002]

2. Description of the Related Art Heretofore, almost no vehicles use methanol fuel (sometimes mixed with gasoline) or hydrogen fuel, and no specific development has been made for these hoses. However, there is an active movement to install a fuel cell using methanol fuel or hydrogen fuel as a next-generation vehicle system, and the development of hoses for fuel cell vehicles such as methanol fuel hose and hydrogen fuel hose used for the fuel cell vehicle has been developed. Needs are growing.

[0003]

However, at present, fuel cell vehicle hoses such as a methanol fuel hose and a hydrogen fuel hose in a prototype fuel cell vehicle of an automobile maker are required to be resistant to methanol permeation and hydrogen permeation. From
Since metal pipes such as stainless steel (SUS) are used, they are very heavy, have poor fuel economy, and have high costs.

The present invention has been made in view of such circumstances, and has as its object to provide a lightweight, low-cost hose.

[0005]

In order to achieve the above object, a hose according to the present invention comprises a rubber layer comprising a rubber composition comprising the following (A) to (D) as essential components; Has a laminated structure of (A) A rubber comprising at least one of an ethylene-propylene-diene terpolymer and an ethylene-propylene copolymer. (B) a peroxide vulcanizing agent. (C) a resorcinol compound. (D) Melamine resin.

That is, the present inventors have made intensive studies to obtain a lightweight and low-cost hose. First, recall that if the conventional metal pipe is a hose having a laminated structure of a metal material layer and a rubber layer, weight reduction can be achieved,
Ethylene-propylene-diene terpolymer (hereinafter abbreviated as "EPDM"), which is relatively inexpensive among rubber materials
And ethylene-propylene copolymer (hereinafter "EPM")
Abbreviated). Then, a hose in which the rubber layer and the metal material layer were bonded by using an adhesive was produced as a trial, but the adhesive force between the rubber layer and the metal material layer was insufficient due to uneven application of the adhesive. In addition, since the step of applying the adhesive is required, the manufacturing process is complicated and the cost is increased. In addition, there is a problem that the pot life of the adhesive is required, the concentration is controlled, and the stable productivity is poor. . Furthermore, since an organic solvent such as toluene is used as a solvent for diluting the adhesive, there is a problem of environmental pollution and the like. Therefore, the research was repeated to obtain a hose having excellent adhesion between the rubber layer and the metal material layer without applying an adhesive to the interface between the rubber layer and the metal material layer. Then, recalling that the adhesive component is kneaded into the EPDM,
As a result of continuing research and development on adhesive components having excellent adhesion to PDM, specific adhesive components (resorcinol-based compound and melamine resin) were kneaded into EPDM and vulcanized using a peroxide vulcanizing agent. It has been found that when vulcanizing, an excellent adhesion to the metal material layer can be obtained, and the present invention has been achieved.
The reason why the rubber layer made of the special rubber composition has excellent adhesive strength to the metal material layer is presumed as follows. The resorcinol compound mainly acts as an adhesive, the melamine resin mainly acts as an adhesion aid, and the resorcinol compound is provided with CH ₂ O from the melamine resin, which is covalently bonded to a metal material. It is believed that the adhesion improves. For example, a resorcinol-based compound represented by the following general formula (C) is provided with CH ₂ O from a melamine resin to form a structure represented by the following general formula (C ′), which is covalently bonded to a metal material. It seems to adhere firmly.

[0007]

Embedded image

[0008]

Embedded image

The resorcinol compound (C)
When the compounding ratio between the rubber layer and the melamine resin (D) is set within a predetermined range, the adhesive strength between the rubber layer and the metal material layer is improved.

Further, when the compounding ratio of the resorcinol compound (C) to the specific rubber (A) is set within a predetermined range, the adhesive strength between the rubber layer and the metal material layer is improved.

[0011]

Next, embodiments of the present invention will be described in detail.

As the hose of the present invention, for example, as shown in FIG. 1, a hose in which a rubber layer 2 made of a special rubber composition is formed on the outer peripheral surface of a metal material layer 1 can be mentioned. The hose having such a configuration is suitably used as a fuel cell vehicle hose such as a methanol fuel hose and a hydrogen fuel hose.

The metal material used as the material for the metal material layer 1 is, for example, iron, iron alloy (SUS or the like), aluminum,
Aluminum alloy, copper, titanium, silver, nickel and the like can be mentioned. Among them, SUS and aluminum are preferably used in terms of weight reduction. As the metal material, it is preferable to use a metal foil (metal film) or the like from the viewpoint of further reducing the weight. The thickness of the metal foil (metal film) is usually in the range of 8 to 400 μm, preferably 15 to 300 μm. Further, bellows processing may be performed on a part or the entire length of the metal material to add flexibility or the like.

The special rubber composition as the material for the rubber layer 2 includes a specific rubber (component A), a peroxide vulcanizing agent (component B), a resorcinol compound (component C), and a melamine resin. (D component).

As the specific rubber (A component), at least one of an ethylene-propylene-diene terpolymer (EPDM) and an ethylene-propylene copolymer (EPM) is used. The EPDM is not particularly limited as long as it is used as a base material of the rubber composition, but preferably has an iodine value in a range of 6 to 30, and an ethylene ratio in a range of 48 to 70% by weight, Preferably, the iodine value is in the range of 10 to 24, and the ethylene ratio is 50.
-60% by weight.

The diene-based monomer (third component) contained in the EPDM is not particularly limited, but has 5 to 5 carbon atoms.
20 diene monomers are preferred.
4-pentadiene, 1,4-hexadiene, 1,5-hexadiene, 2,5-dimethyl-1,5-hexadiene, 1,4-octadiene, 1,4-cyclohexadiene, cyclooctadiene, dicyclopentadiene (DC
P), 5-ethylidene-2-norbornene (ENB),
5-butylidene-2-norbornene, 2-methallyl-5
-Norbornene, 2-isopropenyl-5-norbornene and the like. Among these diene monomers (third component), dicyclopentadiene (DCP), 5
-Ethylidene-2-norbornene (ENB) is preferred.

As the peroxide vulcanizing agent (component B) used together with the specific rubber (component A), for example,
4-dichlorobenzoyl peroxide, benzoyl peroxide, 1,1-di-t-butylperoxy-3,
3,5-trimethylcyclohexane, 2,5-dimethyl-2,5-dibenzoylperoxyhexane, n-butyl-4,4'-di-t-butylperoxyvalerate,
Dicumyl peroxide, t-butylperoxybenzoate, di-t-butylperoxy-diisopropylbenzene, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di-t-butylperoxyhexane,
Di-t-butyl peroxide, 2,5-dimethyl-
2,5-di-t-butylperoxyhexine-3 and the like. These may be used alone or in combination of two or more. Among them, odor is not a problem,
t-Butylperoxy-diisopropylbenzene is preferably used.

The mixing ratio of the peroxide vulcanizing agent (component B) is in the range of 1.5 to 20 parts with respect to 100 parts by weight (hereinafter abbreviated as "parts") of the specific rubber (component A). Is preferred. That is, when the B component is less than 1.5 parts, the crosslinking is insufficient and the strength of the hose is inferior. On the contrary, when the B component exceeds 20 parts, the hardness tends to be too hard and the hose is inferior in flexibility. Because it can be done.

The resorcinol compound (component C) used together with the above components A and B is not particularly limited as long as it mainly acts as an adhesive. For example, modified resorcinol / formaldehyde resin, resorcinol, resorcinol / Formaldehyde (RF) resin and the like. These may be used alone or in combination of two or more. Among these, modified resorcinol-formaldehyde resin is preferably used in terms of transpiration, hygroscopicity, and compatibility with rubber.

Examples of the modified resorcinol-formaldehyde resin include those represented by the following general formulas (1) to (3). Among them, those represented by the following general formula (1) are particularly preferable.

[0021]

Embedded image

[0022]

Embedded image

[0023]

Embedded image

The compounding ratio of the resorcinol compound (component C) is preferably in the range of 0.1 to 10 parts, more preferably 0.5 to 5 parts, per 100 parts of the specific rubber (component A). It is. That is, when the C component is less than 0.1 part, the adhesion to the metal material layer is poor, and conversely, the C component is 1 part.
If the amount exceeds 0, the cost is increased.

The melamine resin (component D) used together with the above components A to C is not particularly limited as long as it mainly acts as an adhesion aid. For example, a methylated formaldehyde / melamine polymer, hexamethylene Tetramine and the like. These may be used alone or in combination of two or more. Among these, a methylated formaldehyde / melamine polymer is preferably used in view of its transpiration, hygroscopicity, and compatibility with rubber.

As the methylated formaldehyde-melamine polymer, for example, those represented by the following general formula (4) are preferably used.

[0027]

Embedded image

Among the melamine resins (component D), a mixture of the compounds represented by the above general formula (4) is preferable. The compound of n = 1 is 43 to 44% by weight, and n = 2.
27 to 30% by weight of the compound of the formula
A mixture of 30% by weight is particularly preferred.

The compounding ratio of the resorcinol compound (component C) to the melamine resin (component D) is preferably in the range of C / D = 1 / 0.5 to 1/2 by weight. And particularly preferably C component / D component = 1 / 0.77-
1 / 1.5. That is, the weight ratio of the D component is 0.5
If it is less than the tensile strength (TB) and elongation (E) of the rubber layer,
B) and other normal physical properties tend to be slightly deteriorated.
When the weight ratio of the components exceeds 2, the adhesiveness is saturated and the adhesive strength is stabilized. Therefore, even if the weight ratio of the D component is further increased,
This is because it only leads to an increase in cost, and no further effect can be expected.

The above-mentioned special rubber composition includes the above-mentioned A
It is preferable to mix carbon black, process oil and the like in addition to the components D to D.

The special rubber composition may optionally contain, in addition to the above components, an antioxidant, a processing aid, a crosslinking accelerator, a white filler, a reactive monomer, a foaming agent, and the like, if necessary. It can be mixed.

The above-mentioned special rubber composition is prepared by blending the above-mentioned components A to D and other components as necessary, and kneading them using a kneader such as a roll, kneader, or Banbury mixer. Can be.

The hose shown in FIG. 1 can be manufactured, for example, as follows. That is, after preparing a long metal tube, extruding the special rubber composition on the surface thereof, and vulcanizing the whole, a desired hose can be manufactured.

The hose shown in FIG. 1 is not limited to the above manufacturing method. For example, a metal foil is wound on a mandrel, and the end of the metal foil is welded in the longitudinal direction. The above-mentioned special rubber composition is extruded and vulcanized to obtain a desired hose.

The thickness of each layer of the hose thus obtained varies depending on the use of the hose, but the thickness of the metal material layer 1 is usually 8 μm to 0.4 mm, and the flexibility and the gas permeability resistance are as follows. Considering the balance, 15 μm to 0.3 mm
Is preferable. The thickness of the rubber layer 2 is usually
It is 0.5-4 mm, preferably 1-3 mm.
Further, the inner diameter of the hose varies depending on the application, but is usually 2 to 40 mm, preferably 4 to 35 mm.

The hose of the present invention is not limited to the two-layer structure of the metal material layer 1 and the rubber layer 2 as shown in FIG. An innermost layer made of a base resin may be formed, or an outermost layer made of another material may be formed on the outer peripheral surface of the rubber layer 2. Also,
Depending on the application of the hose, the rubber layer may be the inner layer and the metal material layer may be the outer layer. The shape of the metal material layer 1 is not particularly limited, and may be any shape such as a straight pipe shape or a bellows shape.

The hose of the present invention can be used to connect the engine to the radiator in vehicles such as gasoline fuel hoses, fuel cell vehicle hoses (methanol fuel hoses, hydrogen fuel hoses), and automobiles by appropriately selecting the configuration of each layer. It can be suitably used as a radiator hose to be used, an engine cooling system hose such as a heater hose used for connecting an engine to a heater core, and an automobile hose such as a refrigerant transfer hose for a cooler. Since EPDM is inferior in gasoline resistance, when used as a gasoline fuel hose, it is desirable to use a rubber layer made of a special rubber composition as a layer other than the inner layer (for example, an outer layer).

Next, examples will be described together with comparative examples.

First, prior to Examples and Comparative Examples, the following rubber compositions were prepared.

[Rubber Composition A] As a specific rubber (A component), EPDM (Esplen 501 manufactured by Sumitomo Chemical Co., Ltd.) is used.
A) 100 parts of [iodine value: 12, ethylene ratio: 50% by weight, Mooney viscosity (ML1 + 4 100 ° C): 43] and carbon black (Tokai Carbon Co., Ltd., Seast S
O) 100 parts, process oil (manufactured by Idemitsu Kosan Co., Diana Process PW-380) 60 parts, and di-t-butylperoxy-diisopropylbenzene (manufactured by NOF Corporation) as a peroxide vulcanizing agent (component B) Peroximon F-4
0) 4.2 parts and a modified resorcinol-formaldehyde resin represented by the general formula (1) as a resorcinol-based compound (component C) (Sumikanol 6 manufactured by Sumitomo Chemical Co., Ltd.)
20) 1 part and 0.77 part of a methylated formaldehyde / melamine polymer (Sumitomo Chemical Co., Ltd., Sumikanol 507A) as a melamine resin (D component),
The rubber composition was prepared by kneading using a roll.

[Rubber Composition B] The mixing ratio of Sumikanol 620 was changed to 5 parts, and the mixing ratio of Sumikanol 507A was changed to 3.85 parts. Except for this, the rubber composition was prepared in the same manner as the rubber composition A.

[Rubber Composition C] The mixing ratio of Sumikanol 620 was changed to 10 parts and the mixing ratio of Sumikanol 507A was changed to 3.85 parts. Except for this, the rubber composition was prepared in the same manner as the rubber composition A.

[Rubber Composition D] A rubber composition was prepared in the same manner as the rubber composition A, except that the mixing ratio of Sumikanol 507A was changed to 0.5 part.

[Rubber Composition E] A rubber composition was prepared in the same manner as the rubber composition A, except that the mixing ratio of Sumikanol 507A was changed to 2 parts.

[Rubber Composition F] The mixing ratio of Sumikanol 620 was changed to 0.1 part and the mixing ratio of Sumikanol 507A was changed to 0.05 part. Except for this, the rubber composition was prepared in the same manner as the rubber composition A.

[Rubber Composition G] A rubber composition G was prepared in the same manner as the rubber composition A except that EPM (Esprene 201, manufactured by Sumitomo Chemical Co., Ltd.) was used instead of EPDM (Esprene 501A, manufactured by Sumitomo Chemical Co., Ltd.). A composition was prepared.

[Rubber Composition a] Both Sumikanol 620 and Sumikanol 507A were not blended. Except for this, the rubber composition was prepared in the same manner as the rubber composition A.

[Rubber Composition b] A rubber composition was prepared in the same manner as in Rubber Composition A except that Sumikanol 507A was not blended.

[Rubber Composition c] Sumikanol 620 was not added, and the mixing ratio of Sumikanol 507A was changed to 1 part. Except for this, the rubber composition was prepared in the same manner as the rubber composition A.

[Rubber Composition d] Instead of 4.2 parts of the peroxide vulcanizing agent (component B), tetramethylthiuram disulfide as a vulcanization accelerator (Suncellar T, manufactured by Sanshin Chemical Co., Ltd.)
T) 0.75 part, zinc dimethyldithiocarbamate (Sanshin Chemical Co., Suncellar PZ) 0.75 part, mercaptobenzothiazole (Sanshin Chemical Co., Suncellar M) 0.5 part, sulfur ( 1.5 parts of a sulfurizing agent). Except for this, the rubber composition was prepared in the same manner as the rubber composition A.

Next, a hose was manufactured using the above rubber composition as follows.

[0052]

EXAMPLE 1 First, a long SUS tube (inner diameter 25 mm, thickness 150 μm) was prepared, and a rubber composition A was extruded on the surface thereof, and then vulcanized at 160 ° C. for 45 minutes to form a rubber layer (thickness 2 mm). To produce the desired hose (see FIG. 1).

[0053]

Examples 2 to 7 and Comparative Examples 1 to 5 Hoses were prepared in the same manner as in Example 1 except that the rubber composition as the material for the outer layer was changed to the rubber compositions shown in Tables 1 and 2 below. Was manufactured. In Comparative Example 2, an adhesive (rubber-based adhesive) was applied to the surface of the metal material layer, and then a rubber layer was formed.

Using the hoses of the examples and the comparative examples thus obtained, each characteristic was evaluated according to the following criteria. These results are shown in Tables 1 and 2 below.
Are also shown. In addition, the tensile strength (T
B) and elongation (EB) are also shown.

[Tensile Strength (TB), Elongation (EB)] The above rubber composition was press-vulcanized at 160 ° C. for 45 minutes to prepare a vulcanized rubber sheet having a thickness of 2 mm. Then, JIS
No. 5 dumbbell was punched out, and the tensile strength (TB) and elongation (EB) were evaluated according to JIS K6301.
As for the tensile strength (TB) and elongation (EB), the larger the value, the better.

[Adhesiveness] A sample (20 mm in width and 100 mm in length) was cut out from the above hose for adhesion evaluation and attached to a tensile tester (JIS B 7721) to fix the rubber layer side and fix the metal material layer side. Was pulled at a speed of 50 mm / min, and the adhesive strength (kg / 25 mm) was evaluated. At that time, the peeling state of the rubber layer and the metal material layer was also visually observed,
When the rubber layer was broken, it was evaluated as ○, and when the interface was peeled, it was evaluated as x.

[Comprehensive evaluation] A sample which does not require the application of an adhesive to the interface between the rubber layer and the metal material layer and has excellent adhesion between the rubber layer and the metal material layer is indicated by "O". Despite applying an adhesive to the interface between the rubber layer and the metal material layer, the adhesive strength between the rubber layer and the metal material layer is poor, or it is unnecessary to apply the adhesive to the interface between the rubber layer and the metal material layer. Those with poor adhesion between the layer and the metal material layer were evaluated as x, and comprehensively evaluated.

[0058]

[Table 1]

[0059]

[Table 2]

From the above results, since the hoses of all the products of the examples use a special rubber composition comprising a resorcinol compound and a melamine resin in combination, the adhesion between the rubber layer and the metal material layer is extremely high. It turns out that it is high.

On the other hand, since the hose of Comparative Example 1 used the rubber composition a containing no adhesive component,
It can be seen that the adhesive strength is extremely low. The hose of Comparative Example 2 has an adhesive applied to the interface between the metal material layer and the rubber layer. However, it can be seen that the adhesive force is lower than that of the hose of Example and the interface peels off. Since the hose of Comparative Example 3 contains the rubber composition b containing only the resorcinol compound and not containing the melamine resin, the hose has low adhesive strength and peels off at the interface. Since the hose of Comparative Example 4 contains only the melamine resin and uses the rubber composition c not containing the resorcinol-based compound,
It can be seen that the adhesive strength is low and interfacial peeling occurs. The hose of Comparative Example 5 contains an adhesive component, but has a low adhesive strength and an interfacial peel because it uses a rubber composition containing a sulfur-based vulcanizing agent instead of a peroxide vulcanizing agent. It can be seen that this occurs. The reason is presumed that the sulfur-based vulcanizing agent has a higher vulcanization rate than the peroxide vulcanizing agent, and the rubber layer itself vulcanizes before bonding to the metal material layer, so that the adhesive strength is poor. You.

[0062]

As described above, since the hose of the present invention has a laminated structure of a rubber layer made of a special rubber composition and a metal material layer, the hose is lower in cost and lighter in weight than a conventional metal pipe. Can be achieved. Therefore, when the hose of the present invention is used for an automobile hose such as a fuel cell vehicle hose, for example, fuel efficiency can be improved by reducing the weight of the hose, and vibration of the vehicle can be improved by using a rubber layer. Can also be absorbed. In addition, since the rubber layer itself has adhesiveness, the adhesiveness between the rubber layer and the metal material layer is excellent without applying an adhesive to the interface between the rubber layer and the metal material layer. In addition, since there is no need for an adhesive application step (so-called adhesive-less), there is no need to worry about pot life of the adhesive or concentration control, etc., and it is excellent in stable productivity and an organic solvent which is a solvent for diluting the adhesive. Because there is no need to use, there is no problem such as environmental pollution. Furthermore, since the vulcanization is performed using a peroxide vulcanizing agent instead of the conventional sulfur vulcanization system, the blending of zinc oxide can be made unnecessary (zinc-free). Even when used as an inner layer of a hose, it is possible to eliminate hose problems such as clogging of the hose and leakage of liquid at the seal portion.

When the mixing ratio of the resorcinol compound (C) and the melamine resin (D) is set within a predetermined range, the adhesive strength between the rubber layer and the metal material layer is improved.

Further, when the compounding ratio of the resorcinol compound (C) to the specific rubber (A) is set within a predetermined range, the adhesive force between the rubber layer and the metal material layer is improved.

[Brief description of the drawings]

FIG. 1 is a sectional perspective view showing an example of a hose of the present invention.

[Explanation of symbols]

 1 Metal material layer 2 Rubber layer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 23/16 C08L 23/16 F16L 9/14 F16L 9/14 // (C08L 23/16 (C08L 23 / 16 61:12 61:12 61:28) 61:28) (72) The inventor, Tomogeshi Hibino, 1-1, Higashi 3-chome, Komaki City, Aichi Prefecture Tokai Rubber Industries Co., Ltd. 1-chome F-term in Tokai Rubber Industries Co., Ltd. (reference) 3H111 AA02 BA02 BA03 BA12 BA13 BA34 CA52 CB03 DA26 DB03 DB08 EA04 4F100 AB00A AB04 AH02B AK36B AK64B AK80B AL01B AN02B BA02 CA03B CA03H DA11 EH17J06 CCB GB11 CC183 CC243 EK036 EK046 EK066 FD146

Claims (3)

[Claims] 1. A hose having a laminated structure of a rubber layer comprising a rubber composition containing the following (A) to (D) as essential components, and a metal material layer. (A) A rubber comprising at least one of an ethylene-propylene-diene terpolymer and an ethylene-propylene copolymer. (B) a peroxide vulcanizing agent. (C) a resorcinol compound. (D) Melamine resin. 2. The weight mixing ratio of (C) and (D) is as follows:
2. The hose according to claim 1, wherein (C) / (D) = 1 / 0.5 to 1/2. 3. The compounding ratio of (C) is (A) 1
The hose according to claim 1 or 2, wherein the amount is set in the range of 0.1 to 10 parts by weight with respect to 00 parts by weight.