JP3030474B2 - Laminated tube for fluid transfer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated tube for transferring fluid.

[0002]

2. Description of the Related Art As a laminated tube for fluid transfer, for example, there is a two-layered structure made of a thermoplastic resin (there are layers where layers are bonded to each other and some layers are not bonded). In general, the outer layer has flame retardancy so that flame resistance can be secured.

A pipe joint 9 of the type shown in FIG. 6 is generally used for connecting this kind of tube. When the tube is connected, a locking claw 92 of an annular plate 91 is connected to the tube. It is configured to be engaged. When the tubes are actually connected, if the layers are adhered to each other, as shown in FIG. 7, the end of the tube in which the inner layer 1 and the outer layer 3 are integrated is inserted as it is, and the layers are connected to each other. In the case where the tube is not bonded, as shown in FIG. 8, only the outer layer 3 at the insertion portion of the tube is peeled and inserted.

[0004] Table 1 shows the results of tests conducted on the above-described fluid-transporting laminated tube for flame resistance, flexibility, and pull-out force of the joint, and also shows the test method.
The test results were obtained for a tube having an outer diameter of 8 mm and an inner diameter of 4 mm. [Test method] "Flame resistance test" Hold the tube vertically and indirectly flame with a gas burner at the lower end of the tube for 10 seconds. After the flame was released, the combustion state of the tube was examined. "Flexibility test" A load (unit: g) required for holding a 400 mm tube end and winding the other end 180 ° around a 100 mm radius semicircle was measured. "Pull-out force of the joint" A sample in which a pipe joint was connected to a tube having a length of 100 mm was attached to a constant-speed tensile tester.
The pipe joint was pulled at a speed of 0 mm / min, and the load (unit: kg) at which the pipe joint was detached was measured.

[0005]

[Table 1]

The hardness shown in Table 1 is all JIS-K6
This is due to the 301-A type. As can be seen from Table 1,
As a result of the above test, the flame resistance, flexibility, and pull-out force of the joint are good, but the workability is very poor because the structure for peeling the outer layer is indispensable at the time of connection. Although it is excellent in flame resistance, joint pull-out force and workability, it has the problem of lack of flexibility.・ Excellent in flexibility and workability, but has a problem that the pull-out force of the joint is small. (The reference value judged to be good is 500 g or less for flexibility, and 43 kg or more).

[0007] In the case of a tube having an intermediate layer having a thickness of 35% of the flame-retardant thermoplastic vinyl chloride-based elastomer layer such as the tube shown in (1), the flexibility, the pull-out force of the joint and the workability are required. However, it has a problem of poor flame resistance. That is, none of the conventional laminated tubes for fluid transfer has good flame resistance, flexibility, pull-out force of joints, and workability.

[0008]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a laminated tube for fluid transfer which is excellent in all of flame resistance, heat shielding, flexibility, workability and joint pulling force. I do.

[0009]

According to the invention of claim 1 of the present application, the laminated tube for transferring fluid has an inner layer made of a thermoplastic resin and a JIS-K6301-A type having a hardness of not more than 80 degrees and not more than 80 degrees. A layer comprising a middle layer made of a flame-retardant thermoplastic elastomer having a thickness of 0.8 mm or more, and a thin outer layer made of a thermoplastic resin having a hardness of 90 degrees or more according to JIS-K6301-A type, and constituting a tube. Glued to each other.

In the invention according to claim 2, the laminated tube for fluid transfer has an inner layer made of a thermoplastic resin having a hardness of more than 80 degrees according to JIS-K6301-A type, and a JIS-K6
The hardness of the 301-A type is 80 degrees or less, the thickness of which is 40% or more of the whole and the intermediate layer made of a flame-retardant thermoplastic elastomer of 0.8 mm or more, and the hardness of the JIS-K6301-A type is 90 degrees or more. And a thin outer layer made of a thermoplastic resin, and the layers constituting the tube are adhered to each other.

Further, the invention according to claim 3 relates to a laminated tube for transferring fluid, which is used for transferring a low-pressure fluid, wherein the hardness according to the JIS-K6301-A type is 80 degrees or less and its thickness is less than 80 degrees. Has an inner layer made of a flame-retardant thermoplastic elastomer of 0.8 mm or more, and a thin outer layer made of a thermoplastic resin having a hardness of 90 degrees or more according to JIS-K6301-A type. Glued.

The invention described in claim 4 is the first invention.
In the inventions of (1) to (3), the thermoplastic resin constituting the outer layer has flame retardancy.

[0013]

The invention of this application has the following functions. Claim 1
The invention described has all the effects shown in the following (1) to (4). (1) Since the intermediate layer is made of a flame-retardant thermoplastic elastomer and has a thickness of 0.8 mm or more, the flame resistance is good. (2) The middle layer and the inner layer have a hardness of 80 degrees or less according to the JIS-K6301-A type, and the outer layer has a hardness of 90 degrees or more according to the JIS-K6301-A type. The properties are good. (3) Since the step of peeling the protective cover becomes unnecessary,
Workability at the time of connection is good. (4) Although the outer layer is thin, since the hardness according to the JIS-K6301-A type is 90 degrees or more, the pull-out force of the joint is good.

Next, the invention according to claim 2 has all the effects shown in the following (1) to (4). (1) Since the intermediate layer is made of a flame-retardant thermoplastic elastomer and has a thickness of 40% or more of the whole and 0.8 mm or more, the flame resistance is good. (2) The outer layer has a hardness of 90 degrees or more according to the JIS-K6301-A type, and the inner layer has a hardness of 80 degrees or more according to the JIS-K6301-A type. Since the thickness of the following intermediate layer is set to 40% or more of the total thickness and 0.8 mm or more, the flexibility of the whole tube becomes good. (3) Since the step of peeling the protective cover becomes unnecessary,
Workability at the time of connection is good. (4) Although the outer layer is thin, since the hardness according to the JIS-K6301-A type is 90 degrees or more, the pull-out force of the joint is good.

The invention according to claim 3 has all of the following effects (1) to (4). (1) Since the inner layer is made of a flame-retardant thermoplastic elastomer and has a thickness of at least 40% of the whole and at least 0.8 mm, the flame resistance is good. (2) The outer layer has a hardness of 90 degrees or more according to the JIS-K6301-A type, but has a hardness of 80 degrees according to the JIS-K6301-A type.
The thickness of the inner layer is less than 40% of the total thickness and 0.8m
m, the flexibility of the tube as a whole is good. (3) Since the step of peeling the protective cover becomes unnecessary,
Workability at the time of connection is good. (4) Although the outer layer is thin, since the hardness according to the JIS-K6301-A type is 90 degrees or more, the pull-out force of the joint is good.

According to the invention described in claim 4,
Flame resistance is further improved as compared with the above-described first to third aspects. The above-mentioned operation will be more apparent from the following specific examples.

[0017]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention; (A) Embodiment 1 Corresponding to the Invention of Claim 3 In this embodiment, as shown in FIG. 1, an inner layer 1 is made of a flame-retardant thermoplastic polyolefin-based elastomer (having a hardness of 80 degrees,
The outer layer 3 is made of high-density polyethylene (having a hardness of 98 degrees and a thickness of 0.2 mm).
These layers are glued together.

When the tube of this embodiment was connected to the pipe joint 1 shown in FIG. 6, the same test as described in the section of the prior art was conducted. As a result, as shown in Table 2, flame resistance and shielding were shown. Good results were obtained in all aspects of thermal properties, flexibility, workability, and joint pull-out force. (B) Embodiment 2 Corresponding to Claim 1 or 2 According to this embodiment, basically, as shown in FIG.
An inner layer 1 made of a thermoplastic resin, an intermediate layer 2 made of a flame-retardant thermoplastic elastomer, and an outer layer 3 made of a thermoplastic resin (the layers are adhered to each other). The settings are as shown in Table 2.

As shown in the same table, good results were obtained for the laminated tubes for fluid transfer of these embodiments in all respects of flame resistance, heat shielding, flexibility, workability, and pull-out force of the joint. (C) Embodiment 3 Corresponding to Claim 1 or 2 In this embodiment, as shown in FIG. 3, FIG. 4 or FIG. 5, an inner layer 1 basically made of a thermoplastic resin is used. And an intermediate layer 2 made of a flame-retardant thermoplastic elastomer, and an outer layer 3 made of a thermoplastic resin. Are referred to as an adhesive layer S), the mode of the layers and the mode of bonding between the layers are set as shown in Table 2.

As shown in the same table, good results are obtained in the fluid transfer laminated tubes of these embodiments in all respects in terms of flame resistance, heat insulation, flexibility, workability, and pull-out force of the joint. Was. In addition, as a method of forming the fluid transfer tube of Examples 1 to 3 described above, any known method such as coextrusion molding or extrusion coating known per se can be adopted, and in particular, a plurality of extruders and a multilayer tube die are used. If co-extrusion molding is used, an endless tube can be efficiently obtained. When a sufficient bonding strength cannot be obtained between the layers due to a combination of materials, an adhesive resin can be applied.

In the following, definitions and the like of the main resins among the above-mentioned resins are shown, and the results obtained by the same method as the test method described in the column of the prior art are shown in Table 2. [Definition of Resin, etc.] (Regarding Flame-Resistant Thermoplastic Elastomer) The flame-retardant thermoplastic elastomer used in the present invention is not particularly limited as long as it is a flame-retardant normal thermoplastic elastomer. However, considering the flexibility of the tube, JIS-K6
Preferably, the hardness of the 301-A type is 80 or less, and its thickness occupies 40% or more of the thickness of the entire tube from the viewpoint of flame retardancy.

As the thermoplastic elastomer, polyolefin, polyamide, polyurethane, polyester, polystyrene, polyvinyl chloride and the like can be suitably used. The method of flame retardation is not particularly limited, but a method using a reactive flame retardant or a method using an additive flame retardant is generally used, and a known treatment method may be used. I can do it.

For example, as the reactive flame retardant, chlorendic acid, tetrabromophthalic anhydride, polyol containing phosphorus or halogen, and the like can be used. Further, as the addition type flame retardant, an inorganic type, a phosphorus type, a halogen type or the like can be suitably used. (Regarding Thermoplastic Resin) The thermoplastic resin used in the present invention is not particularly limited, but those preferably used for tubes include polyolefin-based, polyamide-based, fluorine-based, polyester-based, polyurethane-based, and the like.
There are styrene-based and vinyl chloride-based resins.

When this thermoplastic resin is used for the innermost layer, it is preferable to select it according to the suitability for the fluid to be used, and if necessary, an antioxidant, a coloring agent, an antistatic agent, a plasticizer, Additives such as impact modifiers can be blended. When this thermoplastic resin is used for the outermost layer, the hardness according to the JIS-K6301-A type is 90 or more, and the thickness of the tube increases the flexibility of the tube in order to obtain sufficient connection strength with the joint. Considering this, the thickness is preferably 0.5 mm or less, and the material is not particularly limited. Of course, if necessary as an outer layer material of the tube, antioxidants, coloring agents, UV inhibitors, carbon black, antistatic agents, plasticizers, flame retardants, antifoggants, fillers, preservatives, fungicides, etc. Agents can be used. (Adhesive resin) Examples of the adhesive resin include a thermoplastic resin obtained by grafting or random copolymerizing an unsaturated carboxylic acid or an acid anhydride thereof, and a thermoplastic resin having a functional group such as an epoxy group or a hydroxyl group introduced therein. However, it goes without saying that the present invention is not particularly limited.

If necessary, a reinforcing yarn (for example, a fiber yarn of a polyamide or polyester type, a metal wire, or the like) may be combined between the respective layers. 〔Test results〕

[0026]

[Table 2]

The hardness values shown in Table 2 are all JIS-K6
This is due to the 301-A type.

[0028]

Since the invention of this application has the above-described configuration, it has the following effects. (Effects of the Inventions According to Claims 1 to 3)
(4) As a result, a good laminated tube for fluid transfer could be provided in all of flame resistance, heat shielding, flexibility, workability and joint pull-out force. (Effects of the Invention of Claim 4) Compared with the above-described inventions of Claims 1 to 3, it is possible to provide a laminated tube for fluid transfer which is more excellent in flame resistance and heat insulation.

[Brief description of the drawings]

FIG. 1 is a cross-sectional perspective view of a laminated tube for fluid transfer according to a first embodiment of the present invention.

FIG. 2 is a sectional perspective view of a laminated tube for fluid transfer according to a second embodiment of the present invention.

FIG. 3 is a sectional perspective view of a laminated tube for transferring fluid according to a third embodiment of the present invention.

FIG. 4 is a sectional perspective view of a laminated tube for transferring fluid according to a third embodiment of the present invention.

FIG. 5 is a sectional perspective view of a laminated tube for fluid transfer according to a third embodiment of the present invention.

FIG. 6 is a pipe joint for connecting the laminated tube for fluid transfer.

FIG. 7 is a view showing a state in which a conventional fluid transfer laminated tube is connected using the pipe joint.

FIG. 8 is a diagram showing a state in which a conventional fluid transfer laminated tube is connected using the pipe joint.

[Explanation of symbols]

 1 inner layer 2 middle layer 3 outer layer

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B32B 1/00-35/00 F16L 9/00-9/22 F16L 11/00-11/24

Claims (4)

(57) [Claims] 1. An inner layer made of a thermoplastic resin having a JIS-K6301-A type hardness of not more than 80 degrees, and a flame retardant having a JIS-K6301-A type hardness of not more than 80 degrees and a thickness of 0.8 mm or more. Intermediate layer made of thermoplastic elastomer and JIS-K6
A laminated tube for fluid transfer, comprising a thin outer layer made of a thermoplastic resin having a hardness of 90 degrees or more according to 301-A type, wherein layers constituting the tube are adhered to each other. 2. An inner layer made of a thermoplastic resin having a hardness of more than 80 degrees according to JIS-K6301-A type and a hardness of 80 degrees or less according to JIS-K6301-A type. It has an intermediate layer made of a flame-retardant thermoplastic elastomer of 0.8 mm or more, and a thin outer layer made of a thermoplastic resin having a hardness of 90 degrees or more according to JIS-K6301-A type. A laminated tube for fluid transfer, which is adhered. 3. An inner layer comprising a flame-retardant thermoplastic elastomer having a hardness of not more than 80 degrees and a thickness of not less than 0.8 mm according to a JIS-K6301-A type, which is used for transferring a low-pressure fluid. And a thin outer layer made of a thermoplastic resin having a hardness of 90 degrees or more according to JIS-K6301-A type, wherein the layers constituting the tube are adhered to each other. 4. The laminated tube for fluid transfer according to claim 1, wherein the thermoplastic resin constituting the outer layer has flame retardancy.