JP2007278358A - Fluid transporting tube and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid transporting tube using a thermoplastic elastomer as a base material to form a carbon film on the surface, having high adhesiveness to the carbon film and improved moisture resistance, a gas barrier property, flexibility and ductility, and to provide its manufacturing method. <P>SOLUTION: The fluid transporting tube is formed of a polystyrene base thermoplastic elastomer whose soft segments have principal chains composed of saturated bonds, or a composition containing it. Reforming treatment is applied to the surface to form the carbon film on the surface. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fluid transport tube. More specifically, a thermoplastic elastomer is used as a base material, and a carbon film is formed on the surface thereof. The adhesiveness to the carbon film is high, and moisture resistance, gas barrier property, flexibility and flexibility are provided. The present invention relates to an excellent fluid transport tube and a method for manufacturing the same.

Materials excellent in gas barrier properties are required in many industrial fields from the viewpoints of environmental protection and quality maintenance. For example, in a refrigerant transport tube of an air conditioning system, it is important to suppress the permeation of refrigerant gas from the viewpoint of environmental problems. In addition, a transport tube used for gas transport, chemicals, medical use, beverage transport and the like is similarly required to have high gas barrier properties from the viewpoint of safety and the like. In addition, moisture resistance, gas resistance, corrosion resistance, and chemical resistance are required, and these transport tubes are required to have flexibility such as bending resistance, and are excellent in vibration absorption and assembly workability. Performance is required.
As a material for such a tube body, a vinyl chloride resin system, a silicone resin system, and the like have been used so far, but these have some drawbacks and are not always satisfactory. For example, a vinyl chloride resin tube has a problem that a plasticizer bleeds and a problem that durability is low. In addition, although the silicone resin tube has excellent performance such as durability and chemical resistance, it has a problem of low mechanical strength (particularly tear strength) and high price.

In recent years, polystyrene-based heat represented by styrene-ethylene / propylene-block copolymer (SEPS), styrene-ethylene / butylene-styrene block copolymer (SEBS), and styrene-isobutylene-styrene block copolymer (SIBS). Plastic elastomers have been developed as tube materials.
However, these are excellent in mechanical strength and flexibility, but there is a problem that the water vapor permeability resistance and the gas permeability resistance are not always sufficient.
On the other hand, as a method of improving the gas permeation resistance of the rubber hose, for example, (1) a method of coating a nylon film on the inner surface of the rubber hose (see, for example, Patent Document 1), and (2) hose by covering the inner tube made of nylon with rubber (For example, refer to Patent Document 2) and the like are disclosed.
However, none of these methods has sufficient gas permeation resistance, and there is a problem that it is difficult to continuously produce a rubber hose in particular with the method (1).
Further, although not a rubber hose, a method using an organosilane coating film as a gas barrier film in order to improve the gas permeation resistance of a plastic film is known (for example, see Patent Documents 3 and 4).
However, it has been difficult to apply this method to a hose application with a large deformation using an organosilane coating film as a gas barrier film.

On the other hand, in the field of polymers, especially packaging film materials, methods for improving barrier properties include improvement of the molecular structure of the polymer, multi-layering such as dry lamination using an adhesive and extrusion lamination by a melt adhesion method. Known are nanocomposites in which inorganic compounds are finely dispersed in the order of nano-molecules, surface modification methods such as resin coating (emulsion method, resin method) and inorganic material coating (evaporation).
However, when this multilayering or nanocomposite technique is applied to, for example, the above-mentioned polystyrene-based thermoplastic elastomer base material, the flexibility of the thermoplastic elastomer may be impaired. It has been found that the resin is difficult to be fixed on the surface of the thermoplastic elastomer substrate.

Also, a liquid supply tube in which diamond-like carbon (DLC) having a high gas barrier property is formed on the inner surface for the purpose of stably supplying liquid ink has been proposed (see Patent Document 5 and Claim 7). It is also disclosed that a thermoplastic synthetic resin is used as the material of the liquid supply tube (see Patent Document 5 and Claim 9).
However, since there is no specific disclosure about the thermoplastic resin here, the adhesion of the DLC film is unknown, and the DLC film may peel off. Moreover, since the DLC film is used on the inner surface of the liquid supply tube, there is a possibility that the DLC film peels off due to a pressure change in the liquid supply tube and flows into the fluid.

JP 59-123661 A JP 60-11388 A Japanese Patent Laid-Open No. 62-112635 JP-A-2-286331 JP-A-2005-319608

  The object of the present invention is to provide a fluid transport that uses a thermoplastic elastomer as a base material, has a carbon film formed on the surface thereof, has high adhesion to the carbon film, has excellent moisture resistance, gas barrier properties, flexibility and flexibility. An object of the present invention is to provide a tube and a method for producing the same.

As a result of intensive studies to achieve the above object, the present inventor has obtained a tube for fluid transportation obtained by using a thermoplastic elastomer or a composition thereof containing no double bond in a soft segment as a base material. It has been found that a fluid transport tube having a carbon film formed on the surface thereof by a surface modification treatment such as a plasma CVD method can achieve the object. The present invention has been completed based on such findings.
That is, the present invention
(1) (A) A fluid transport tube made of a polystyrene-based thermoplastic elastomer or a composition containing the same, wherein the main chain of the soft segment is a saturated bond. A fluid transport tube characterized in that a carbon film is formed;
(2) The fluid transport tube according to (1), wherein the surface modification treatment is performed by a plasma CVD method,
(3) The above (1), wherein the composition comprising the polystyrene-based thermoplastic elastomer of component (A) is a composition in which 0.1 to 50 parts by mass of a polyolefin resin is blended with 100 parts by mass of the thermoplastic elastomer. Or the fluid transport tube of (2),
(4) The polystyrene-based thermoplastic elastomer of component (A) is styrene-isobutylene-styrene block copolymer (SIBS), styrene-ethylene / butylene-styrene block copolymer (SEBS), and styrene-ethylene / propylene-styrene. The fluid transport tube according to any one of the above (1) to (3), which is at least one selected from the group consisting of block copolymers (SEPS);
(5) The fluid transport tube according to (4), wherein the polystyrene-based thermoplastic elastomer of component (A) is a styrene-isobutylene-styrene block copolymer (SIBS),
(6) The fluid transport tube according to any one of (1) to (5) above, wherein the hardness of the thermoplastic elastomer of component (A) is 80 degrees or less in accordance with JIS-A standards,
(7) The fluid transport tube according to (1) to (6), wherein the carbon film is a film made of diamond-like carbon (DLC).
(8) The fluid transport tube according to any one of (1) to (7) above, wherein a carbon film is formed on the outer surface of the fluid transport tube.
(9) (A) A method for producing a fluid transport tube comprising a polystyrene-based thermoplastic elastomer or a composition containing the same, wherein the main chain of the soft segment is a saturated bond, and the surface is subjected to a modification treatment. A manufacturing method of a tube for fluid transportation characterized by forming a carbon film, and (10) the manufacturing method of the tube for fluid transportation of (9), wherein the surface modification treatment is performed by a plasma CVD method,
Is to provide.

  According to the present invention, it is possible to obtain a fluid transport tube having high adhesion to a carbon film and excellent in moisture resistance, gas barrier properties, flexibility and flexibility.

The component (A) polystyrene-based thermoplastic elastomer used in the present invention (hereinafter sometimes referred to as component (A)) does not contain a double bond in the soft segment, that is, the soft segment is saturated in the main chain. Use a bond.
The component (A) has an aromatic vinyl polymer block (hard segment) and a rubber block (soft segment), and the aromatic vinyl polymer portion forms a physical crosslink and becomes a crosslinking point, The rubber block gives elasticity. Further, in order to obtain excellent deterioration resistance, it is important that the rubber block does not contain a double bond.

Examples of the aromatic vinyl-based compound forming the aromatic vinyl-based polymer block include styrene; α-alkyl-substituted styrene such as α-methylstyrene, α-ethylstyrene, α-methyl-p-methylstyrene; o- Methyl styrene, m-methyl styrene, p-methyl styrene, 2,4-dimethyl styrene, ethyl styrene, 2,4,6-trimethyl styrene, ot-butyl styrene, pt-butyl styrene, p-cyclohexyl styrene Nucleoalkyl-substituted styrenes such as o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, p-bromostyrene, 2-methyl-4-chlorostyrene, and the like.
Among these, styrene, α-methylstyrene, and p-methylstyrene are preferable, and styrene is particularly preferable.
These aromatic vinyl compounds may be used individually by 1 type, and may be used in combination of 2 or more type.

This component (A) is composed of styrene-isobutylene-styrene block copolymer (SIBS), styrene-ethylene / butylene-styrene block copolymer (SEBS), styrene-ethylene / propylene, depending on the arrangement pattern of the soft segments therein. Block copolymer (SEPS), block copolymer of crystalline polyethylene and ethylene / butylene-styrene random copolymer obtained by hydrogenating a block copolymer of polybutadiene and butadiene-styrene random copolymer For example, there is a diblock copolymer of crystalline polyethylene and polystyrene obtained by hydrogenating a block copolymer of polybutadiene or ethylene-butadiene random copolymer and polystyrene.
Among these, in view of mechanical strength, heat stability, weather resistance, chemical resistance, gas barrier properties, flexibility, workability, etc., styrene-isobutylene-styrene block copolymer (SIBS), styrene-ethylene / Butylene-styrene block copolymer (SEBS) and styrene-ethylene / propylene block copolymer (SEPS) are preferable, and styrene-isobutylene-styrene block copolymer (SIBS) having excellent adhesion to a carbon film. Is particularly preferred. The content of the styrene block in these components (A) is preferably 10 to 70% by mass, and more preferably in the range of 20 to 40% by mass.

The hardness of the component (A) is preferably 80 degrees or less in accordance with JIS-A standards. When the hardness is 80 degrees or less, sufficient flexibility as a molded body can be obtained. In view of the above, the hardness is more preferably 70 degrees or less and particularly preferably 60 degrees or less in the JIS-A standard.
The weight average molecular weight of the component (A) is not particularly limited, but is preferably in the range of 40,000 to 120,000 in terms of gas barrier properties, mechanical properties, moldability, and the like. Is preferably in the range of 60,000 to 100,000.

In addition, as the composition containing the component (A) (hereinafter sometimes referred to as “elastomer composition”), various components other than the component (A) can be blended. From the viewpoint of improving the processability and heat resistance of the product, resin components such as polyolefin resins and polystyrene resins (hereinafter sometimes simply referred to as “resin components”) can be preferably mentioned, and polyolefin resins are particularly preferred. .
The polyolefin resin is not particularly limited. For example, polyethylene, isotactic polypropylene, a copolymer of propylene and a small amount of other α-olefin (for example, propylene-ethylene copolymer, propylene / 4-methyl-1- Pentene copolymer), poly (4-methyl-1-pentene), polybutene-1, and the like. When isotactic polypropylene or a copolymer thereof is used as the polyolefin resin, those having an MFR (JIS K7210) of 0.1 to 50 g / 10 min, particularly 0.5 to 30 g / 10 min can be preferably used. .
In addition, (A) component contained in an elastomer composition can be used individually by 1 type and in combination of 2 or more types.

Next, as the polystyrene resin that can be blended as a component other than the component (A), those obtained by a conventionally known production method, for example, those obtained by any of the radical polymerization method and the ionic polymerization method are preferably used. it can.
The number average molecular weight of the polystyrene resin used here is preferably selected from the range of 5,000 to 500,000, more preferably 10,000 to 200,000, and the molecular weight distribution is preferably 5 or less.
Examples of the polystyrene resin include polystyrene, a styrene-butadiene block copolymer having a styrene unit content of 60% by mass or more, rubber-reinforced polystyrene, poly α-methylstyrene, poly pt-butylstyrene, and the like. You may use together 1 type, or 2 or more types.
Furthermore, a copolymer obtained by polymerizing a mixture of monomers constituting these polymers can also be used.
Moreover, the said polyolefin resin and polystyrene resin can also be used together.
For example, when these resins are added to the elastomer composition, when a polystyrene resin is used in combination as compared with the case where a polyolefin resin alone is added, the hardness of the resulting molded product tends to increase.
Therefore, the hardness of the obtained molded body can be adjusted by selecting these blending ratios.
In this case, the ratio of polyolefin resin / polystyrene resin is preferably selected from the range of 95/5 to 5/95 (mass ratio).

It is preferable that the compounding quantity of the resin component in an elastomer composition is about 0-100 mass parts with respect to 100 mass parts of (A) component, for example, in the case of polyolefin resin, especially 0.1-50 mass. Part is more preferred.
When the blending amount of the resin component is 100 parts by mass or less, it is preferable that the hardness of the obtained molded body does not become too high.

A softening agent can be further added to the elastomer composition. As the softening agent, usually a liquid or liquid one is suitably used at room temperature.
The softener having such properties can be appropriately selected from, for example, various rubber or resin softeners such as mineral oil and synthetic.
Here, examples of mineral oils include process oils such as naphthenic and paraffinic oils. Among them, non-aromatic oils, particularly mineral oil-based paraffinic oils, naphthenic oils, or synthetic polyisobutylene-based oils. One or two or more selected from oils having a number average molecular weight of 450 to 5,000 is preferable.
In addition, these softeners may be used individually by 1 type, and may mix and use 2 or more types if mutual compatibility is favorable.
Although the compounding quantity of a softener does not have a restriction | limiting in particular, It is 1-1000 mass parts normally with respect to 100 mass parts of (A) component, Preferably it is chosen in the range of 1-500 mass parts.
When the blending amount is 1 part by mass or more, the hardness can be reduced, and sufficient flexibility can be obtained when the fluid transport tube is formed. On the other hand, if it is 1,000 parts by mass or less, bleeding of the softening agent can be suppressed, and sufficient mechanical strength of the molded product can be obtained.
In addition, the compounding quantity of this softening agent can be suitably selected in the said range according to the molecular weight of a thermoplastic elastomer, and the kind of other component added to this thermoplastic elastomer.

The elastomer composition can be blended with a polyphenylene ether resin as desired for the purpose of improving the compression set of the resulting molded article.
As the polyphenylene ether resin, known ones can be used. Specifically, poly (2,6-dimethyl-1,4-phenylene ether), poly (2-methyl-6-ethyl-1,4- Phenylene ether), poly (2,6-diphenyl-1,4-phenylene ether), poly (2-methyl-6-phenyl-1,4-phenylene ether), poly (2,6-dichloro-1,4-phenylene ether) And a polyphenylene such as a copolymer of 2,6-dimethylphenol and a monovalent phenol (for example, 2,3,6-trimethylphenol or 2-methyl-6-butylphenol). Ether copolymers can also be used.
Of these, poly (2,6-dimethyl-1,4-phenylene ether) and a copolymer of 2,6-dimethylphenol and 2,3,6-trimethylphenol are preferable. Dimethyl-1,4-phenylene ether) is preferred.
The compounding quantity of polyphenylene ether resin can be suitably selected in the range of 10-250 mass parts with respect to 100 mass parts of (A) component.
When the blending amount is 250 parts by mass or less, the hardness of the obtained molded article does not become too high and becomes moderate, and when it is 10 parts by mass or more, the effect of improving the compression set of the obtained molded article is sufficient.

Further, the elastomer composition of the present invention includes clay, diatomaceous earth, silica, talc, barium sulfate, calcium carbonate, magnesium carbonate, metal oxide, mica, graphite, flaky inorganic additives such as aluminum hydroxide, Metal powder, glass powder, ceramic powder, granular or powdered solid filler such as granular or powdered polymer, other various natural or artificial short fibers, long fibers (such as various polymer fibers), etc. it can.
Moreover, weight reduction can be achieved by mix | blending the hollow filler, for example, organic hollow fillers, such as inorganic hollow fillers, such as a glass balloon and a silica balloon, a polyvinylidene fluoride, a polyvinylidene fluoride copolymer.
Furthermore, in order to improve various physical properties such as weight reduction, it is possible to mix various foaming agents, and it is also possible to mix gas mechanically during mixing.

  In addition, the elastomer composition of the present invention includes, as necessary, other flame retardants, antibacterial agents, hindered amine light stabilizers, ultraviolet absorbers, antioxidants, colorants, silicone oils, silicone polymers. Various adhesive elastomers such as coumarone resin, coumarone-indene resin, phenol terpene resin, petroleum hydrocarbons, rosin derivatives and other tackifiers (tackfire), Reostomer B (trade name: manufactured by Riken Technos Co., Ltd.), HYBLER (trade name: manufactured by Kuraray Co., Ltd., a block copolymer in which polystyrene blocks are connected to both ends of a vinyl-polyisoprene block), Norex (trade name: manufactured by Nippon Zeon Co., Ltd.), ring-opening polymerization of norbornene In combination with other thermoplastic elastomers or resins. It is possible.

The silicone polymer has a weight average molecular weight of 10,000 or more, preferably 100,000 or more. The said silicone polymer improves the surface adhesiveness of the molded object using the said elastomer composition.
As the silicone polymer, a general-purpose thermoplastic polymer such as polyethylene, polypropylene, or polystyrene blended at a high concentration can be used in order to improve the handleability.
In particular, a blended product with polypropylene has good workability and physical properties.
As such a material, for example, a material readily available as a silicone concentrate BY27 series general-purpose type commercially available from Toray Dow Corning Silicone Co., Ltd. may be used.

The manufacturing method of the said elastomer composition is not specifically limited, A well-known method is applicable.
For example, each of the above components and optional additive components are melt-kneaded using a heating kneader, for example, a single screw extruder, twin screw extruder, roll, Banbury mixer, plastic bender, kneader, high shear mixer, etc. Furthermore, it can be easily produced by adding a crosslinking agent such as an organic peroxide, a crosslinking aid or the like, if necessary, or mixing these necessary components at the same time, followed by heating, melt-kneading.
In addition, a thermoplastic material prepared by kneading a polymer organic material and a softener is prepared in advance, and this material is further mixed with one or more types of polymer organic materials that are the same type or different from those used here. You can also
Furthermore, the elastomer composition can be crosslinked by adding a crosslinking agent such as an organic peroxide, a crosslinking aid or the like.

The fluid transport tube of the present invention needs to be subjected to a surface modification treatment to form a carbon film on the surface.
As a method of forming a carbon film, a plasma CVD method, a sputtering method, an ion plating method, etc. can be used as a method capable of forming a film in a temperature range that does not cause thermal damage to the thermoplastic elastomer of the component (A) as a base material. The plasma CVD method is particularly preferable.
Usually, prior to the formation of the carbon film, the film forming surface of the substrate is selected from pretreatment gases such as fluorine (F) -containing gas, hydrogen (H ₂ ) gas, and oxygen (O ₂ ) gas as pretreatment. Exposure to the plasma of at least one pretreatment gas. By this operation, the substrate surface is cleaned, or the substrate surface roughness is further improved. These contribute to improving the adhesion of the carbon film and can obtain a highly adherent carbon film. However, when the plasma CVD method is used, the pretreatment by the plasma of the deposition target substrate and the carbon film deposition are performed. The same apparatus can be used, and excellent adhesion between the carbon film and the substrate can be obtained.
In particular, the effect is conspicuous by the combination with the thermoplastic elastomer of the component (A) as a base material.

The plasma CVD method uses plasma energy generated in a vacuum vessel using high-frequency power or the like to cause a chemical reaction such as decomposition and bonding of the source gas in a low-pressure environment to heat the substrate. In this method, a carbon film is formed on a substrate in a temperature range (for example, 45 to 65 ° C.) that does not cause mechanical damage.
As a plasma source gas for forming a carbon film by plasma CVD, methane (CH ₄ ), ethane (C ₂ H ₆ ), propane (C ₃ H ₈ ), butane (C ₄ ), which are generally used for forming a carbon film, are used. H _10), acetylene (C ₂ H _2), benzene (C ₆ H _6), 4 fluorinated carbon (CF _4), 6 fluorinated 2 carbon (C ₂ F ₆₎ carbon compounds such as gases, and optionally A mixture of these carbon compound gases with hydrogen gas, inert gas or the like as a carrier gas can be used.
The formed carbon film is preferably diamond-like carbon (DLC). The DLC has an amorphous structure including the same carbon SP ³ bond as natural diamond, the same carbon SP ² bond as graphite, and a hydrogen bond.
The DLC film has good lubricity, is not easily worn by friction with other articles, and the substrate coated with the film has flexibility by adjusting its thickness. In some cases, the base material can have an appropriate hardness so as not to impair the inherent flexibility of the base material. In addition, water repellency, gas barrier properties and electrical insulation are good. Furthermore, the film can be formed easily, such as being formed at a relatively low temperature as described above.
In addition, the carbon film can be formed with good adhesion on the base material, and can sufficiently function the object of the present invention as a protective film for the base material, and the base material has flexibility. In this case, it may be within a range that does not impair the inherent flexibility of the substrate. Specifically, a range of 0.3 to 1.5 μm is preferable.

The fluid transport tube of the present invention uses the aforementioned component (A) or a composition containing the same to produce a tube-shaped molded body by a conventionally known method such as extrusion molding, injection molding, inflation, etc. It can be obtained by forming a carbon film on the surface by plasma CVD or the like.
When a carbon film is formed on a tube-shaped substrate, it can be formed on the outside (outer surface) or inside (inner surface) of the tube. When the change is large and the carbon film is partially peeled off and may flow into the fluid, it is preferable to form the carbon film on the outside of the tube. Further, from the viewpoint of imparting a sufficient gas barrier property to the tube, it is possible to form a film on both the outer side and the inner side of the tube. In the case of forming a film on the outer side of the tube-shaped base material, for example, the base material is rotated by a rotation driving means so that the film can be formed almost uniformly on the outer surface of the base material. In addition, when forming a film in the tube, the film can be easily formed by inserting a plasma generation source into the tube.

The fluid transport tube of the present invention thus obtained has an air permeability [JIS K7126; method A (differential pressure method), conforming to 40 ° C.], usually 200 × 10 ⁻⁵ cm ³ / m ² · It is 24 hr · Pa or less and has excellent gas barrier properties. The air permeability is preferably 100 × 10 ⁻⁵ cm ³ / m ³ · 24 hr · Pa or less, more preferably 5 × 10 ⁻⁵ cm ³ / m ² · 24 hr · Pa or less, and further preferably 1 × 10 ^{− 5} cm ³ / m ² · 24 hr · Pa or less.
Furthermore, the water vapor transmission rate (based on JIS Z0208; 40 ° C., 90% RH) is usually 2.0 g / m ² · 24 hr or less, and has excellent barrier properties against water vapor. The water vapor permeability is preferably 1.5 g / m ² · 24 hr or less, more preferably 1.2 g / m ² · 24 hr or less, and still more preferably 1.0 g / m ² · 24 hr or less.
The inner diameter of the fluid transport tube of the present invention is appropriately selected depending on the application, but is usually about 0.1 to 3 mm, preferably 0.5 to 2 mm. The wall thickness is usually about 0.1 to 2 mm, preferably 0.5 to 1.5 mm, although it depends on the inner diameter.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
(Evaluation methods)
(1) Bending resistance: Evaluation was made by the behavior when a tube (length: about 30 cm) whose surface was modified with a carbon film was repeatedly bent. Evaluation was performed according to the following criteria.
○: The carbon film was not peeled. Δ: The carbon film was peeled off slightly.
×: The carbon film was peeled off (2) Moisture resistance: The tube was measured under the conditions of 40 ° C. and 90% RH according to JIS Z0208.
(3) Gas permeation resistance: The tube was measured according to JIS K7126 A method (differential pressure method) 40 ° C.

Example 1
Styrene-isobutylene-styrene block copolymer [SIBS: "SIBSTAR073T" manufactured by Kaneka Co., Ltd., weight average molecular weight Mw = about 70,000, styrene block content 30% by mass] 100 parts by mass of polypropylene [Idemitsu Kosan Co., Ltd. ) "H-700"] Using a compound containing 5 parts by mass, the tubes shown in Table 1 were heated and pressed under the production conditions of a mold temperature of 80 ° C and a resin temperature of 180 ° C. A sheet having a thickness of 0.5 mm × 100 mm × 100 mm was produced by extrusion molding. Carbon films were formed on the outer and inner surfaces of the tube under the film forming conditions shown in Table 1. The moisture resistance and air permeation resistance were measured using a sheet, and the flex resistance was measured using a tube. The results are shown in Table 1.

Comparative Example 1
The same procedure as in Example 1 was performed except that no carbon film was formed. The measurement results of moisture resistance, air permeation resistance and flex resistance are shown in Table 1.

Comparative Example 2
The same procedure as in Example 1 was performed except that a styrene-butadiene-styrene block copolymer [SBS: weight average molecular weight Mw = about 70000, styrene block content 30 mass%] was used instead of SIBS. The measurement results of moisture resistance, air permeation resistance and flex resistance are shown in Table 1.

Comparative Example 3
The same procedure as in Example 1 was performed except that gold was sputtered (thickness: 300 nm) instead of the carbon film. The measurement results of moisture resistance, air permeation resistance and flex resistance are shown in Table 1.

The fluid transportation tube of the present invention has high adhesion to the carbon membrane, has excellent moisture resistance, gas barrier property (air permeability resistance), and good flexibility, and is used for refrigerant transportation, gas transportation, and chemicals. It is suitable for applications such as tubes for fluid transportation such as for medical use, medical use, beverage transportation, and ink transportation.

Claims (10)

  (A) A fluid transport tube comprising a polystyrene-based thermoplastic elastomer or a composition containing the same, wherein the main chain of the soft segment is a saturated bond, the surface of which is modified, and a carbon film is formed on the surface A tube for transporting fluid, which is formed into a film.   The fluid transport tube according to claim 1, wherein the surface modification treatment is performed by a plasma CVD method.   The composition containing (A) component polystyrene-based thermoplastic elastomer is a composition in which 0.1 to 50 parts by mass of a polyolefin resin is blended with 100 parts by mass of the thermoplastic elastomer. Tube for fluid transportation.   The polystyrene-based thermoplastic elastomer (A) is a styrene-isobutylene-styrene block copolymer (SIBS), a styrene-ethylene / butylene-styrene block copolymer (SEBS), or a styrene-ethylene / propylene-styrene block copolymer. The fluid transport tube according to any one of claims 1 to 3, which is at least one selected from the group consisting of coalescence (SEPS).   The fluid transport tube according to claim 4, wherein the polystyrene-based thermoplastic elastomer (A) is a styrene-isobutylene-styrene block copolymer (SIBS).   (A) The hardness of the polystyrene-type thermoplastic elastomer of a component is 80 degrees or less by JIS-A specification, The tube for fluid conveyance in any one of Claims 1-5.   The tube for fluid transportation according to any one of claims 1 to 6, wherein the carbon film is a film made of diamond-like carbon (DLC).   The fluid transport tube according to any one of claims 1 to 7, wherein a carbon film is formed on an outer surface of the fluid transport tube.   (A) A method for producing a fluid transport tube comprising a polystyrene-based thermoplastic elastomer or a composition containing the same, wherein the main chain of the soft segment is a saturated bond, the surface of which is modified, and a carbon film on the surface A method for producing a fluid transport tube, characterized in that a film is formed. The method for producing a fluid transport tube according to claim 9, wherein the surface modification treatment is performed by a plasma CVD method.