JP3126275B2 - Fuel transfer tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel transfer tube, and particularly to a fuel transfer tube having excellent barrier properties and excellent breaking resistance, not only for gasoline fuel but also for mixed fuel containing alcohol. Particularly, the present invention relates to a fuel transfer tube suitable for a fuel tube of a transportation vehicle such as an automobile which is used by being bent in a narrow space.

[0002]

2. Description of the Related Art Conventionally, metal pipes, rubber hoses, and the like have been used as fuel transfer tubes for transportation vehicles such as automobiles.
A single-layer tube made of nylon or a tube having a multilayer structure in which various resins are laminated is used.

[0003] On the other hand, as for the fuel situation, since the supply of gasoline cannot be said to be sufficient in the future, alternative fuels are being studied. As one of them, a mixed fuel in which alcohol such as methanol is blended with gasoline has been studied.
It has already been partially commercialized in Europe and the United States. The use of methanol as a fuel is also expected to improve the octane number and purify exhaust gas.

[0004] Further, considering the atmospheric environment, it is preferable that the emission of fuel from the transportation vehicle is as small as possible, the emission regulations are becoming more and more strict, and it is desired that the permeation from tubes be lower. It is rare.

[0005] Incidentally, the fuel tube may be installed in the vehicle in order to prevent the fuel tube from being damaged by an impact at the time of a vehicle collision, and to protect against a stepping stone or a flame from outside the vehicle. In this case, since the odor of the permeated gas from the fuel tube may make the occupant uncomfortable or depending on the concentration of the permeated gas there is a risk of ignition, the permeation of gas from the fuel tube should be as close to zero as possible. Longed for.

[0006] On the other hand, the piping space of automobiles is becoming smaller and smaller, and there is a strong demand for piping to avoid other equipment.

[0007] It is well known that rust prevention and weight reduction are demanded from the demand for the improvement of durability and fuel economy of transportation vehicles.

A conventional example of this type of fuel transfer tube is disclosed in Japanese Patent Application Laid-Open No. Hei 4-224384. The fuel transfer tube is a single-layer tube made of a polyester resin or a multilayer tube having at least an innermost layer made of a polyester resin. In this fuel transfer tube, polybutylene terephthalate having particularly excellent fuel barrier properties is used as the polyester resin in order to improve the fuel barrier properties.

[0009] As another conventional example, German Patent Application Publication Nos. 4112662, 4137430, and 413
Nos. 7431 and 4215608 disclose a multi-layered fuel transfer tube having an inner layer and an outer layer mainly composed of polyamide and an intermediate layer composed of linear crystalline polyester.

In this case, the intermediate layer is formed from a mixture of a linear crystalline polyester and a polyamide or a compound having various reactive groups in order to suppress the fuel permeability and improve the adhesion between the layers. Has also been proposed.

[0011]

However, according to the experimental results of the present inventors, it has been confirmed that the fuel transfer tube having a multilayer structure using polybutylene terephthalate as the innermost layer has the following disadvantages. Was.

There is a limit in improving the fuel barrier property.

[0013] The reason is that the fuel for transportation vehicles such as automobiles is a mixture of various components, and while exhibiting sufficient fuel barrier properties for a fuel of a certain composition, it is difficult to use a fuel of another composition. On the other hand, sufficient fuel barrier properties cannot be exhibited, and as a result, the overall fuel barrier properties become insufficient.

In the tube described in the examples of the publication, the inner layer is formed of polybutylene terephthalate, and the outer layer is formed of nylon 12, since the adhesion between the two layers is poor, there is a problem in the fold resistance of the tube. there were.

As described above, a fuel transfer tube of this type used for a transportation vehicle is often provided in a very narrow space with a small bending radius, and therefore requires flexibility. Therefore, if the breaking resistance is low, it cannot be put to practical use.

When handling an alcohol-mixed fuel in a fuel transfer tube using a polyester resin such as polybutylene terephthalate for the innermost layer, the innermost layer may be deteriorated by hydrolysis due to a trace amount of water contained in the alcohol. Therefore, there is a problem in durability.

Further, according to the experimental results of the present inventors,
In order to improve the adhesiveness with the polyamide used for the inner and outer layers, it has been found that a multi-layer fuel transfer tube using a mixture of polybutylene terephthalate and various compounds as an intermediate layer has the following disadvantages.

There is a limit in improving the fuel barrier property.

Regarding the latter of the above-mentioned conventional example, as described in a comparative example described later, polybutylene terephthalate is used as the linear crystalline polyester forming the intermediate layer, or a polyamide resin is used instead of polybutylene terephthalate.
Tubes obtained using a mixture of maleic anhydride-modified EPM or a mixture of ethylene-ethyl acrylate-glycidyl methacrylate copolymer, etc., have a high fuel density despite the fact that an intermediate layer is formed using polybutylene terephthalate. The barrier properties decrease. The fuel transfer tube of the present invention has been made in order to solve the above-mentioned drawbacks, and the purpose thereof is to provide a sufficient fuel even for a methanol-mixed fuel as an alternative fuel or a current gasoline fuel. An object of the present invention is to provide a fuel transfer tube that can exhibit barrier properties and chemical resistance.

Another object of the present invention is to provide a fuel transfer tube which can improve the breaking resistance and is particularly suitable for a fuel tube of a transportation vehicle such as an automobile.

Still another object of the present invention is to use a fluorine-based resin or a polyamide-based resin as the material of the innermost layer, so that it has excellent resistance to hydrolysis and fuel oil, and does not deteriorate over time. It is an object of the present invention to provide a fuel transfer tube that can significantly improve durability as compared with the fuel transfer tube described above.

[0022]

A fuel transfer tube according to the present invention comprises an innermost layer made of one selected from the group consisting of a fluorine-based resin and a polyamide-based resin, and surrounds the innermost layer and has an intrinsic viscosity of 0.1 . Polybutylene naphate of 9 to 1.5
An intermediate layer made of a tartrate resin, an outer layer made of a thermoplastic resin or a thermoplastic elastomer, and an adhesive layer formed between the innermost layer and the intermediate layer, whereby the object is achieved. You.

[0023]

In a further preferred embodiment, the thickness of the intermediate layer is 5 to 20% of the total wall thickness of the tube.

In a further preferred embodiment, the innermost layer is made of a polyamide resin, and the adhesive layer is made of thermoplastic polyurethane, polyether block amide, polyester block amide, modified polyolefin, polyester copolymer and polyester elastomer. At least one selected from the group consisting of:

In a further preferred embodiment, the innermost layer is made of a polyamide resin, and the adhesive layer is made of an adhesive resin containing a polyamide resin and a crystalline polyester or a polyester elastomer. The mixing ratio of the crystalline polyester or the polyester-based elastomer is 70/3 by volume.
The range is 0 to 30/70.

In a further preferred embodiment, the adhesive resin further comprises an epoxy compound containing a glycidyl group or a glycidyl ether group, an acid anhydride, an oxazoline group, a carboxylic acid group, an isocyanate group, a (meth)
A compatibilizer selected from the group consisting of a compound having an acrylic acid or (meth) acrylate ester skeleton, a compound having an amino group and a hydroxyl group is melt-mixed.

In a further preferred embodiment, the innermost layer is made of a fluorine-based resin, and the adhesive layer is made of at least one selected from the group consisting of a fluorine-based resin, a soft fluorine-based resin and a fluorine-based rubber; The adhesive resin contains at least one selected from the group consisting of a polyester resin and a polyester elastomer.

In a further preferred embodiment, the innermost layer is made of a fluorine-based resin, and the adhesive layer is made of at least one selected from the group consisting of a fluorine-based resin, a soft fluorine-based resin and a fluorine-based rubber; An adhesive resin containing at least one selected from the group consisting of a polyester-based resin and a polyester-based elastomer, wherein the mixing ratio is 80/20 to 20 /
The range is 80.

In a further preferred embodiment, the adhesive resin further comprises an epoxy compound containing a glycidyl group or a glycidyl ether group, an acid anhydride, an oxazoline group, a carboxylic acid group, an isocyanate group, a (meth)
A compatibilizer selected from the group consisting of a compound having an acrylic acid or (meth) acrylate ester skeleton, a compound having an amino group and a hydroxyl group is melt-mixed.

Hereinafter, the present invention will be described in detail.

FIG. 1 shows a cross section of a preferred embodiment of the fuel transfer tube of the present invention.

The fuel transfer tube 1 has a five-layer structure, and has an innermost layer 10, an adhesive layer 11, an intermediate layer 12, an adhesive layer 13, and an outer layer 14 from the inside.

The fuel transfer tube 1 can be manufactured by the following method.

An extruder for forming the innermost layer 10, an extruder for forming the adhesive layer 11, an extruder for forming the intermediate layer 12, and an adhesive layer 13
A total of five extruders, an extruder for forming and an extruder for forming the outer layer 14, are arranged around the mold, and the molten resin is extruded from each extruder to each layer in the mold and laminated. The molten resin is discharged from the tip of the mold, and the diameter and thickness of the tube are adjusted in a sizing bath so as to have a predetermined size while cooling the molten tube having a five-layer structure.

The present invention includes, in addition to the tube having the five-layer structure described above, a tube having a four-layer structure shown in FIG. This four-layer tube has four
Except for using a base extruder, the tube can be manufactured by the same method as the above-described method for manufacturing a tube having a five-layer structure.

Each resin is generally about 150 to 320
C., especially at a temperature in the range of 190 to 280.degree.

The dimensions of the fuel transfer tube 1 in the illustrated example are as follows:
There is no particular limitation. For example, when manufacturing a fuel tube for an automobile having a five-layer structure having an outer diameter of 8 mm and an inner diameter of 6 mm, the thickness of each layer of the tube is preferably set as follows in terms of implementation. Thickness of innermost layer 10: 0.1 to 0.3 mm Thickness of adhesive layer 11: 0.02 to 0.1 mm Thickness of intermediate layer 12: 0.05 to 0.2 mm Thickness of adhesive layer 13: 0 0.02 to 0.1 mm Thickness of outer layer 14: 0.3 to 0.8 mm On the other hand, when manufacturing a four-layer automotive fuel tube having an outer diameter of 8 mm and an inner diameter of 6 mm, the thickness of each layer of the tube is It is preferable to set as follows.

The thickness of the innermost layer 10: 0.05 to 0.2 mm The thickness of the adhesive layer 11: 0.02 to 0.1 mm The thickness of the intermediate layer 12: 0.05 to 0.2 mm The thickness of the outer layer 14 : 0.5 to 0.85 mm When the thickness of the innermost layer 10 is thinner than the above range, the compatibility with the joint to be connected is deteriorated, and the joint is connected to the tube or during use. Therefore, there is a risk that the innermost layer is cut. If the inner layer is thicker than the above range, the flexibility of the entire tube is impaired and the cost is increased.

When the thickness of the adhesive layer 11 is smaller than the above range, stable moldability cannot be obtained and a uniform thickness cannot be controlled in some cases. As a result, the adhesive strength becomes uneven. When the thickness is larger than the above range, when obtaining a tube having a predetermined diameter and thickness, as a result, the innermost layer, the intermediate layer, and the outer layer have to be thinned, which impairs the tube characteristics intended by the present invention. Will be.

If the thickness of the intermediate layer 12 is smaller than the above range, sufficient fuel barrier properties cannot be obtained. If the thickness is larger than the above range, the flexibility of the entire tube is impaired or the impact resistance is poor. become.

If the thickness of the adhesive layer 13 is smaller than the above range, stable moldability cannot be obtained and a uniform thickness cannot be controlled in some cases. As a result, the adhesive strength becomes uneven.

When the thickness is larger than the above range, when obtaining a tube having a predetermined diameter and thickness, the innermost layer, the intermediate layer and the outer layer have to be thinned as a result. The tube characteristics will be impaired.

If the thickness of the outer layer 14 is smaller than the above range, the weather resistance is inferior, the inner layer cannot be protected from the impact of stepping stones or the like, or an external chemical solution (for example, an antifreezing agent, rust preventive paint, etc. If the thickness of the outer layer 14 is larger than the above range, the thickness of the innermost layer and the intermediate layer may be reduced when a tube having a predetermined diameter and thickness is obtained. This will inevitably impair the tube properties which are the object of the present invention.

(Innermost layer 10) As the material of the innermost layer 10, a fluorine resin or a polyamide resin is used.
Its thickness is 5 to 30 times the total thickness of the fuel transfer tube 1.
% Is preferred.

Fluorine-based resins Fluorine-based resins are originally excellent in corrosion resistance and chemical resistance, as well as non-water-absorbing, abrasion-resistant, non-adhesive, self-lubricating, heat- and cold-resistant, and weather-resistant. But very good. Among these fluororesins, the melt viscosity of polytetrafluoroethylene is 3
At 80 ° C., there are 10 ³ to 10 ¹² poises, and although it is a thermoplastic resin, it has poor thermoplasticity and cannot be normally melt-molded.

Therefore, as the fluororesin used in the fuel transfer tube of the present invention, a thermoplastic resin which can be extruded is used. For example, a polyvinylidene fluoride resin (hereinafter abbreviated as PVDF), ethylene-4 Ethylene copolymer resin (ETFE), vinyl fluoride resin (PVF), ethylene / 3 fluorochlorinated ethylene copolymer resin (E · CTF)
E) Trifluoroethylene chloride resin (PCTFE), tetrafluoroethylene hexafluoropropylene copolymer resin (FE
P) tetrafluoroethylene / perfluoroalkoxyethylene copolymer resin (PFA) and tetrafluoroethylene / hexafluoropropylene / perfluoroalkoxyethylene copolymer resin (EPA).

Among these, PVDF and ETFE are particularly preferred in consideration of moldability and adhesiveness to other resins.

The PVDF is a homopolymer of vinylidene fluoride or a copolymer of vinylidene fluoride and a monomer copolymerizable with vinylidene fluoride. Examples of the copolymerizable monomer include vinyl fluoride, ethylene tetrafluoride, ethylene chloride trifluoride, and propylene hexafluoride.

The ETFE is preferably one having a molar ratio of ethylene / 4-fluoroethylene in the range of 30/70 to 60/40, and if necessary, copolymerization with a small amount of another copolymerizable monomer. Also includes polymers.

[0051] As the polyamide resin used in the polyamide resin present invention, high molecular weight linear polyamide is preferably used. The polyamide can be any of a homopolyamide, a copolyamide or a mixture thereof.

Examples of such polyamides include homopolyamides, copolyamides, and mixtures thereof having an amide repeating unit represented by the following formula (1) or (2).

-CO-R ¹ -NH- (1) -CO-R ² -CONH-R ³ -NH (2) wherein R ¹ , R ² , R ³ represents a linear alkylene group.

Here, considering the barrier properties and fuel oil resistance to gasoline fuels and alcohol-mixed fuels, the polyamide resin used in the present invention has the number of amide groups per 100 carbon atoms in the polyamide resin. Is 3 to 3
Preference is given to 0, especially 4 to 25 homopolyamides, copolyamides or mixtures thereof.

Specific examples of suitable homopolyamides include:
Polycapramid (nylon 6), poly-ω-aminoheptanoic acid (nylon 7), poly-ω-aminononanoic acid (nylon 9), polyundecaneamide (nylon 11),
Polylaurin lactam (nylon 12), polyethylene diamine adipamide (nylon 2,6), polytetramethylene adipamide (nylon 4,6), polyhexamethylene adipamide (nylon 6,6), polyhexamethylene se Bacamide (nylon 6,10), polyhexamethylene dodecamide (nylon 6,12), polyoctamethylene adipamide (nylon 8,6), polydecamethylene adipamide (nylon 10,6), polydecamethylene Sebacamide (nylon 10, 10), polydodecamethylene dodecamide (nylon 12, 12) and the like can be mentioned.

Examples of the copolyamide include caprolactam / laurin lactam copolymer, caprolactam / hexamethylene diammonium adipate copolymer,
Laurin lactam / hexamethylene diammonium adipate copolymer, hexamethylene diammonium adipate / hexamethylene diammonium sebacate copolymer, ethylene diammonium adipate / hexamethylene diammonium adipate copolymer, caprolactam / hexamethylene diammonium adipate / Hexamethylene diammonium sebacate copolymer and the like can be mentioned.

In order to impart flexibility to these polyamide resins, plasticizers such as aromatic sulfonamides, p-hydroxybenzoic acid, and esters, elastomer components having a low modulus of elasticity, and lactams are used. You may mix.

Examples of the elastomer component include ionomer resin, modified polyolefin resin, thermoplastic polyurethane, polyether block amide, polyester block amide, polyether ester amide elastomer, polyester elastomer, modified styrene thermoplastic elastomer, modified acrylic Rubber, modified ethylene
And propylene rubber.

In particular, these elastomer components have a flexural modulus of 3000 kg which is compatible with the polyamide resin.
f / cm ² or less is preferable, and these elastomers can be used alone or in combination.

The material of the innermost layer 10 may be made of various additives (for example, an antioxidant, a coloring agent,
Antistatic agent, flame retardant, reinforcing agent, stabilizer, processing aid, conductive material, etc.).

(Intermediate Layer 12) In the fuel transfer tube 1 of the present invention, a polyalkylene naphthalate resin is used as the material of the intermediate layer 12.

The polyalkylene naphthalate resin used in the present invention refers to a resin produced by condensing naphthalenedicarboxylic acid or an ester-forming derivative thereof and a diol under appropriate reaction conditions in the presence of a catalyst. .

Examples of the naphthalenedicarboxylic acid include naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, and naphthalene-1,5-dicarboxylic acid, and one or more of these may be used. used.

Examples of the ester-forming derivative of naphthalenedicarboxylic acid include methyl naphthalene-2,6-dicarboxylate.

As the diol, an alkylene glycol is preferably used. Examples of such an alkylene glycol include ethylene glycol, propylene glycol, trimethyl glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol and the like.

A particularly preferred polyalkylene naphthalate resin used in the present invention is polyethylene naphthalate using naphthalene-2,6-dicarboxylic acid as naphthalenedicarboxylic acid and ethylene glycol or 1,4 butanediol as alkylene glycol. Alternatively, it is polybutylene naphthalate.

When the fuel transfer tube 1 is used as a fuel tube for an automobile, the material of the intermediate layer 12 is polybutylene in consideration of various points such as fuel barrier properties, mechanical strength as a tube, and moldability. Naphthalate is particularly preferred.

The higher the viscosity of the polyalkylene naphthalate resin is, the higher the strength, impact strength and elongation are, the higher the intrinsic viscosity thereof (based on ASTM D 2857, using o-chlorophenol as a solvent at 35 ° C., 0.005 g). / Ml) is preferably 0.7 or more, more preferably 0.9 to 1.5.

As long as the effect of the fuel transfer tube 1 of the present invention, such as the fuel barrier property, is not impaired, the polyalkylene naphthalate resin may be partially substituted with the naphthalenedicarboxylic acid or alkylene glycol component of each polyester component. Or a copolymer substituted with a third component such as another dicarboxylic acid, oxycarboxylic acid, or dioxy compound.

Examples of such a dicarboxylic acid include various naphthalenedicarboxylic acids, terephthalic acid, isophthalic acid, adipic acid, oxalic acid, and diphenyl ether dicarboxylic acid.

Examples of the oxycarboxylic acid include various p-oxybenzoic acids and p-oxyethoxybenzoic acid.

Examples of the dioxy compound include dihydric alcohols such as ethylene glycol, propylene glycol, trimethyl glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, diethylene glycol and bisphenol A, polyethylene glycol and polytetramethylene glycol. And polyalkylene glycols such as

Further, if necessary, the polyalkylene naphthalate resin may have another resin or an elastomer component, or a functional group in order to improve adhesion, as long as the fuel barrier property of the present invention is not affected. The compound may be melt-mixed or may contain various additives (for example, an antioxidant, a colorant, an antistatic agent, a flame retardant, a reinforcing agent, a stabilizer, a processing aid, and a conductive material).

The thickness of the intermediate layer 12 is 5 to 2 times the total thickness.
0% is preferred. When the thickness of the intermediate layer 12 is less than 5% of the total thickness, the fuel barrier property is poor.
It is not preferable because the flexibility of the entire tube is impaired and the impact resistance is deteriorated.

Further, the polyalkylene naphthalate resin has such a property that the breaking strength and the breaking elongation increase as the wall thickness becomes thinner. Excellent impact strength and toughness.

(Outer Layer 14) As described above, when a fluorine-based resin or a polyamide-based resin is used as the innermost layer 10 and a polyalkylene naphthalate resin is used as the intermediate layer 12, the fuel transfer according to the present invention is used. In the tube 1, the material forming the outer layer 14 is not particularly limited as long as it is a thermoplastic resin.

The material for forming the outer layer 14 is, for example, polyamide resin, fluorine resin, polyester resin, polyurethane elastomer, polyamide elastomer,
Examples include thermoplastic resins such as polyester elastomers, polyacetal resins, polyolefin resins such as polyethylene and polypropylene.

For example, in the case of a tube having an outer diameter of 25 mm or less, the thickness of the entire tube is preferably 5 to 20% of the outer diameter of the tube. 85% is preferred. The reason is as follows.

When the thickness of the entire tube is extremely thin with respect to the outer diameter of the tube, the tube 1 buckles when the tube 1 is bent, and the tube 1 breaks to interrupt the flow of the internal fluid. There is a risk that it will. When the terminal of the tube 1 needs to be connected to another device, a joint is usually required, but in that case, an appropriate tube thickness is required.

The properties required for the outer layer 14 of the tube 1 include weather resistance, scratch resistance, abrasion resistance, flexibility (flexibility), flame retardancy, coloring, printing, antistatic properties, In order to provide insulation, pressure resistance, conductivity, and the like, another layer having these characteristics may be laminated. For example, when the tube 1 is required to have antistatic properties and conductivity, a surface layer made of a resin having a volume resistivity of about 10 ² to 10 ⁹ Ω · cm may be coated on the outside of the outer layer 14. When a higher pressure resistance is required for the tube 1, a reinforcing layer braided or wrapped with a synthetic fiber (for example, nylon, vinylon, polyester, or aramid fiber) or a wire is provided outside the outer layer 14. You can also.

Further, injuries caused by heat of the outside air, stepping stones, etc.
In order to protect the tube from a flame or the like, the tube may be covered with a rubber tube or a thermoplastic elastomer, or may have a structure in which a coil tube is wound.

(Adhesive layer 11) The adhesive resin used for the adhesive layer 11 provided together with the five-layer fuel transfer tube 1 and the four-layer fuel transfer tube 1 is laminated at the time of co-extrusion molding. Innermost layer 10 and intermediate layer 12
There is no particular limitation as long as it can have heat-fusibility.

For example, the innermost layer 10 made of a fluororesin
And intermediate layer 12 composed of polyalkylene naphthalate resin
As the adhesive resin used for the adhesive layer 11 formed between the resin and at least one compound (F) selected from the group consisting of a fluorine-based resin, a soft fluorine-based resin, and a fluorine-based rubber, A molten mixture with at least one compound (PE) selected from the group consisting of polyester-based resins and polyester-based elastomers is preferred,
Further, in order to obtain a more homogeneously mixed adhesive resin or to further enhance the adhesive strength, one or more kinds of thermoplastic polyurethane, polyamide-based elastomer, modified polyolefin, etc. were added to the mixture and melt-mixed. What has a so-called compatibilizer having a functional group, for example, an epoxy compound containing a glycidyl group or a glycidyl ether group, an acid anhydride, an oxazoline group, an isocyanate group, a carboxylic acid group, or an amino group. The composition can be suitably used.

The adhesive resin used for the adhesive layer 11 formed between the innermost layer 10 made of a polyamide-based resin and the intermediate layer 12 made of a polyalkylene naphthalate resin includes thermoplastic polyurethane, polyether block amide, and the like. One or a mixture of two or more of polyester block amide, modified polyolefin, polyester copolymer, and polyester elastomer is preferred.

Further, as the adhesive resin, a resin obtained by melt-mixing a polyamide resin and a crystalline polyester resin and / or a polyester elastomer can be used, and in order to obtain a more uniformly mixed adhesive resin. And one of the above adhesive resins to further increase the adhesive strength
Or a mixture of two or more kinds and melt-mixed, a functional group,
For example, a carboxylic acid group, an acid anhydride, a compound having a (meth) acrylic acid or (meth) acrylate ester skeleton, an epoxy compound containing a glycidyl group or a glycidyl ether group, an oxazoline group, an isocyanate group, an amino group, a hydroxyl group, etc. A composition melt-mixed using a so-called compatibilizer having the formula (I) can be suitably used.

The mixture ratio of the two or more kinds of adhesive resins used for the adhesive layer 11 described above is such that the adhesive force between the innermost layer 10 and the intermediate layer 12 is uniform, and a sufficient value for use. Is preferably selected so as to obtain

In the adhesive resin used between the fluororesin and the polyalkylene naphthalate resin, the mixing ratio of the compound (F) and the compound (PE) is 8 by volume.
The range is preferably 0/20 to 30/70, and more preferably 70/30 to 30/70 in volume ratio. It is preferable that the above-mentioned thermoplastic polyurethane, polyamide-based elastomer, modified polyolefin and compatibilizer are mixed at 30% by volume or less based on the mixture.

When the polyamide resin and the crystalline polyester resin and / or the polyester elastomer are used as the adhesive resin used between the polyamide resin and the polyalkylene naphthalate resin, the polyamide resin and the crystalline polyester resin are used. And / or the mixing ratio of the polyester elastomer is 70/30 to 3 by volume ratio.
The range of 0/70 is preferable, and the volume ratio is 60%.
/ 40 to 40/60 is more preferred. As the compatibilizer, it is preferable to mix at 20% by volume or less based on the mixture.

The thickness of the adhesive layer 11 is not particularly limited as long as the adhesive function between the innermost layer 10 and the intermediate layer 12 is achieved as described above, but is preferably 2 to 10% of the entire tube thickness.

If the thickness of the adhesive layer 11 is less than 2% of the total tube thickness, stable moldability cannot be obtained and uniform thickness may not be controlled, resulting in poor adhesive strength. If it is not uniform and exceeds 10%, when obtaining a tube having a predetermined diameter and thickness, the innermost layer, the intermediate layer and the outer layer must be made thinner as a result. You will lose.

(Adhesive Layer 13) As the resin used for the adhesive layer 13 provided only in the fuel transfer tube 1 having a five-layer structure, the intermediate layer 12
The material is not particularly limited as long as it can be thermally fused to the outer layer 14.

Examples of the resin used for such an adhesive layer 13 include thermoplastic polyurethane, polyether block amide, polyester block amide, modified polyolefin, polyester copolymer, and polyester elastomer. A mixture of two or more is used.

The thickness of the adhesive layer 13 is not particularly limited as long as the adhesive layer 13 has an adhesive function between the intermediate layer 12 and the outer layer 14, but is preferably 2 to 10% of the wall thickness of the entire tube.

If the thickness of the adhesive layer 13 is less than 2% of the entire tube thickness, stable moldability cannot be obtained and uniform thickness may not be controlled, resulting in poor adhesive strength. If it is uniform, if it exceeds 10%, the innermost layer, the intermediate layer and the outer layer have to be thinned as a result, which impairs the original properties of the tube.

When the intermediate layer 12 and the outer layer 14 have heat-sealing properties, it is not necessary to provide the adhesive layer 13 between the two layers, and a four-layer fuel transfer tube can be obtained.

(Fuel Transfer Tube) The fuel transfer tube having a multilayer structure as described above can be molded by any known molding method such as coextrusion molding and extrusion coating. For example, it can be efficiently formed by co-extrusion using a plurality of extruders according to the layer configuration and a tube die for a multilayer.

By such a molding method, the innermost layer is a fluorine-based resin or a polyamide-based resin, the intermediate layer is a polyalkylene naphthalate resin, and the outer layer is a thermoplastic resin. Fuel transfer with a structure having no adhesive layer between the intermediate layer and the outer layer) or five layers (type having an adhesive layer between the innermost layer and the intermediate layer and between the intermediate layer and the outer layer) Tubes can be manufactured. The obtained tube has excellent fuel barrier properties and breakage resistance, as can be seen from the description of Examples below.

[0098]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on embodiments.

The test methods for evaluating the transmission speed and the breaking resistance of the tubes obtained in the following Examples and Comparative Examples are as follows.

A. Transmission speed: outer diameter 8 mm, inner diameter 6 mm,
Each of the following sample liquids was sealed in a tube having a length of 1000 mm, left in an oven at 60 ° C. and 40 ° C., the change over time in weight loss was determined, and the value obtained by dividing the outer surface area of the tube by g / m ² / day was obtained. It was calculated and used as the transmission speed.

Sample liquid: Fuel C: Reagent grade toluene and reagent grade isooctane mixed at a volume ratio of 1: 1.

Alcohol-mixed fuel: Fuel C and methanol mixed at a volume ratio of 85:15.

B. Bending resistance: A tube having an outer diameter of 8 mm and an inner diameter of 6 mm is bent in a semicircular shape, the bending radius is gradually reduced, the bending radius (mm) immediately before the tube is broken is determined, and the value is used as a measure of bending resistance. did. Therefore, the smaller the bending radius immediately before breaking, the better the breaking resistance.

(Example 1) This tube 1 has an innermost layer 10 (thickness 0.2 mm) formed of nylon 11 and an adhesive layer 11 (thickness 0.2 mm) formed of thermoplastic polyurethane.
05 mm), an intermediate layer 12 (thickness 0.1 mm) formed of polybutylene naphthalate, an adhesive layer 13 (thickness 0.05 mm) formed of thermoplastic polyurethane, and an outer layer formed of nylon 11 14 (0.6mm thick)
And

This tube was obtained as follows. Nylon 11, polybutylene naphthalate in three extruders,
Each of the thermoplastic polyurethanes is charged and 220
After plasticizing at processing temperatures of ~ 240 ° C, 230-250 ° C and 190-210 ° C, a three-type five-layer tube having an outer diameter of 8 mm and an inner diameter of 6 mm was extruded from a three-type five-layer tube die controlled at 245 ° C. .

(Example 2) This tube 1 has an innermost layer 10 (thickness 0.2 mm) formed of nylon 11 and an adhesive layer 11 (thickness 0.0) formed of a modified polyolefin.
5 mm), an intermediate layer 12 (thickness 0.1 mm) formed of polybutylene naphthalate, an adhesive layer 13 (thickness 0.05 mm) formed of modified polyolefin, and an outer layer 14 formed of nylon 11. (Thickness: 0.6 mm).

The forming temperature of the adhesive layers 11 and 13 is set to 230 to 2
A tube was obtained in the same manner as in Example 1 except that the temperature was changed to 40 ° C.

Example 3 This tube 1 has an innermost layer 10 (thickness 0.2 mm) made of nylon 11 and a thermoplastic polyurethane and polyester elastomer 5.
/ 5 (volume ratio) of an adhesive layer 11 (thickness 0.05 mm), an intermediate layer 12 made of polybutylene naphthalate (thickness 0.1 mm), thermoplastic polyurethane, polyester-based Adhesive layer 13 (thickness 0.05 m) formed of a 5/5 (volume ratio) mixture of elastomers
m) and an outer layer 14 (thickness: 0.
6 mm).

The molding temperature of the adhesive layers 11 and 13 is set to 210 to 2
A tube was obtained in the same manner as in Example 1, except that the temperature was changed to 30 ° C.

(Example 4) The tube 1 is a mixture of an innermost layer 10 (0.2 mm in thickness) made of nylon 11 and 5/5 (volume ratio) of a polyether block amide and a polyester elastomer. Adhesive layer 11 to be formed
(Thickness: 0.05 mm), an intermediate layer 12 (thickness: 0.1 mm) formed of polybutylene naphthalate, and polyether block amide and polyester elastomer.
Adhesive layer 13 (thickness: 0.05 mm) formed of a mixture of / 5 (volume ratio) and outer layer 14 formed of nylon 11
(Thickness: 0.6 mm).

The molding temperature of the adhesive layers 11 and 13 is set to 230 to 2
A tube was obtained in the same manner as in Example 1 except that the temperature was changed to 40 ° C.

(Example 5) This tube has the same structure as that of Example 4 except that the intermediate layer 12 was formed using polyethylene naphthalate instead of polybutylene naphthalate.

The processing temperature of the intermediate layer 12 is 280 to 300
A tube was obtained in the same manner as in Example 4 except that the temperature of the three-layer five-layer tube die was set to 270 to 280 ° C.

(Example 6) The tube 1 was made of an innermost layer 10 (0.2 mm thick) made of nylon 11 and 4/4/1 (volume ratio) of nylon 11, polybutylene terephthalate, and thermoplastic polyurethane. ) And an intermediate layer 12 (0.1 mm in thickness) formed of polybutylene naphthalate.
And an outer layer 14 formed of a polyester elastomer.
(Thickness: 0.65 mm).

The tube was obtained as follows. 4
Each resin used for the innermost layer 10, the adhesive layer 11, the intermediate layer 12, and the outer layer 14 is put in a single extruder, and each of the resins is 210 to 2
40 ° C, 210-240 ° C, 230-250 ° C and 2
After plasticizing at a processing temperature of 20 to 240 ° C., an outer diameter of 8 mm and an inner diameter of 6 were obtained from a four-type four-layer tube die controlled at 245 ° C.
4 mm four-layer tubes were extruded.

(Example 7) This tube 1 has an innermost layer 10 (thickness 0.2 mm) formed of nylon 11 and 5/5/1 (volume ratio) of nylon 11 / polyester elastomer / modified polyolefin. The adhesive layer 11 (thickness 0.05 mm) formed of a mixture of the above and the intermediate layer 12 (thickness 0.1 mm) formed of polybutylene naphthalate
And an adhesive layer 13 (wall thickness 0.05 mm) formed of a mixture of nylon 11 / polyester-based elastomer / modified polyolefin (5/5/1 (volume ratio)) and nylon 11
And an outer layer 14 having a thickness of 0.6 mm.

This tube was obtained as follows. 3
Nylon 11, polybutylene naphthalate, a mixture of nylon 11 / polyester-based elastomer / modified polyolefin (5/5/1 (volume ratio)) were placed in two extruders, and the mixture was 220 to 240 ° C., 240 to 260 ° C.,
After plasticizing at a processing temperature of 30 to 250 ° C, a tube was extruded from a three-type five-layer tube die controlled at 260 ° C.

The tubes obtained in Examples 1 to 7 were measured for transmission speed and breaking resistance. Table 1 shows the test results together with the configuration of the tubes of each example. Note that a high permeation rate means that the fuel barrier properties of the tube are low.

[0119]

[Table 1]

(Embodiment 8) This tube 1 has an innermost layer 10 (having a thickness of 0.1 m) made of polyvinylidene fluoride.
m) and 4/4/1 (by volume) of polyvinylidene fluoride, polybutylene terephthalate, and thermoplastic polyurethane
Layer 11 made of a mixture of (thickness 0.05 mm)
And an intermediate layer 12 made of polybutylene naphthalate
(Thickness 0.1 mm), an adhesive layer 13 (thickness 0.05 mm) formed of thermoplastic polyurethane, and nylon 11
And an outer layer 14 having a thickness of 0.6 mm.

This tube was obtained as follows. Each resin used for the innermost layer 10, the adhesive layer 11, the intermediate layer 12, the adhesive layer 13, and the outer layer 14 is put into five extruders, and the resin is used at 200 to 220 ° C, 200 to 220 ° C, 230 to 250
After plasticizing at a processing temperature of 190 ° C., 190 ° C. to 210 ° C. and 220 ° to 240 ° C., a five-layer five-layer tube having an outer diameter of 8 mm and an inner diameter of 6 mm was extruded from a five-layer five-layer tube die controlled at 245 ° C.

(Example 9) This tube 1 has an innermost layer 10 (thickness 0.1 mm) formed of polyvinylidene fluoride / propylene hexafluoride copolymer, a soft fluororesin, a polyester elastomer, An adhesive layer 11 (thickness 0.05 mm) formed of a mixture of 5/4/1 (volume ratio) of a plastic polyurethane, and an intermediate layer 12 (thickness 0.1 mm) formed of polybutylene naphthalate; An adhesive layer 13 made of thermoplastic polyurethane (having a thickness of 0.0
5 mm) and an outer layer 14 (0.7 mm thick) made of nylon 11.

The forming temperature of the innermost layer 10 is 190 to 21.
A tube was obtained in the same manner as in Example 8, except that the temperature was changed to 0 ° C.

(Example 10) This tube 1 is made of an innermost layer 10 made of an ethylene / tetrafluoroethylene copolymer.
(Thickness: 0.1 mm) and 2/5/3 of soft fluororesin, polyester elastomer and modified polyolefin
(Volume ratio) of the adhesive layer 11 (thickness: 0.1).
05 mm), an intermediate layer 12 (thickness 0.1 mm) formed of polybutylene naphthalate, and an outer layer 14 (0.75 mm thickness) formed of a polyester elastomer.
And

This tube was manufactured in the same manner as in Example 6 using four extruders and four types of four-layer tube dies. The molding temperature is 230-260 ° C. for the innermost layer 10 and the bonding layer 11
Is 220-240 ° C and the temperature of the tube die is 25.
Controlled at 0 ° C., four-type four-layer tubes were formed.

(Example 11) This tube 1 is made of an innermost layer 10 made of an ethylene / tetrafluoroethylene copolymer.
(Thickness: 0.1 mm) and an adhesive layer 11 (thickness: 0.1 mm) formed of a mixture of ethylene / tetrafluoroethylene copolymer / polybutylene terephthalate / ethylene glycidyl methacrylate = 5/5/1 (volume ratio). 05 mm) and an intermediate layer 12 (thickness: 0. 5 mm) formed of polybutylene naphthalate.
1 mm), an adhesive layer 13 (thickness 0.05 mm) formed of a mixture of nylon 11 / polyester elastomer / modified polyolefin = 5/5/1 (volume ratio), and an outer layer 14 formed of nylon 11 (thickness: 0.05 mm). 0.6mm thick)
And

This tube was obtained as follows. Each resin used for the innermost layer 10, the adhesive layer 11, the intermediate layer 12, the adhesive layer 13, and the outer layer 14 is put into five extruders, and each is placed at 270 to 290 ° C, 250 to 270 ° C, and 240 to 260 ° C.
After plasticizing at a processing temperature of 230 ° C., 230 to 250 ° C. and 220 to 240 ° C., a five-type five-layer tube having an outer diameter of 8 mm and an inner diameter of 6 mm was extruded from a five-type five-layer tube die controlled at 260 ° C.

The transmission speed and the breaking resistance of the tubes obtained in Examples 8 to 11 were measured. Table 2 shows the test results together with the configuration of the tubes of each example.

[0129]

[Table 2]

(Comparative Examples 1 to 5) The tube of Comparative Example 1
It is made of nylon 11 and has a single-layer thickness of 1 mm.

The tube of Comparative Example 2 is made of polyvinylidene fluoride and has a single-layer thickness of 1 mm.

The tube of Comparative Example 3 was made of an ethylene / tetrafluoroethylene copolymer and had a single-layer thickness of 1 mm.

The tube of Comparative Example 4 was made of polybutylene terephthalate resin, and was a single layer having a thickness of 1 mm.

The tube of Comparative Example 5 was made of polyethylene terephthalate resin and was a single layer having a thickness of 1 mm.

Comparative Example 6 The tube of Comparative Example 6 has an innermost layer 10 made of polybutylene terephthalate resin (thickness 0.7 mm) and an outer layer 14 made of nylon 12 (thickness 0.3 mm). .

(Comparative Example 7) The tube of Comparative Example 7 was made of a cyclohexanedimethanol / ethylene glycol / terephthalic acid copolymer and had a single layer thickness of 1 mm.

Comparative Example 8 The tube of Comparative Example 8 has an innermost layer 10 made of nylon 12 (0.2 mm thick), an intermediate layer 12 made of polybutylene terephthalate (0.2 mm thick), and nylon 12 And an outer layer 14 (having a thickness of 0.6 mm).

(Comparative Example 9) The tube of Comparative Example 9 has an innermost layer 10 (thickness 0.1 mm) made of nylon 12 and polybutylene terephthalate resin / nylon 12 / triphenylene phosphite = 50/50/0. It has an intermediate layer 12 (wall thickness 0.15 mm) made of a 1 (weight ratio) mixture and an outer layer 14 (wall thickness 0.75 mm) made of nylon 12.

(Comparative Example 10) The tube of Comparative Example 10 was
Innermost layer 10 made of nylon 12 (wall thickness 0.1 mm)
An intermediate layer 12 (thickness 0.15 mm) composed of a mixture of polybutylene terephthalate resin / maleic anhydride-modified EPM = 80/20 (weight ratio), and an outer layer 14 (thickness 0.75 mm) composed of nylon 12. And

(Comparative Example 11) The tube of Comparative Example 11 was
Innermost layer 10 made of nylon 12 (wall thickness 0.2 mm)
And a middle layer 12 (wall thickness 0.2 mm) composed of a mixture of polybutylene terephthalate resin / isocyanurate of isophorone diisocyanate = 90/10 (weight ratio)
And the outer layer 14 made of nylon 12 (0.6 mm thick)
And

(Comparative Example 12) The tube of Comparative Example 12 was
Innermost layer 10 made of nylon 11 (wall thickness 0.2 mm)
And an adhesive layer 11 made of thermoplastic polyurethane (thickness 0.05 mm), an intermediate layer 12 made of polybutylene terephthalate (thickness 0.1 mm), and an adhesive layer 13 made of thermoplastic polyurethane (thickness 0.05 mm). ) And an outer layer 14 made of nylon 11 (thickness: 0.6 mm).

(Comparative Example 13) The tube of Comparative Example 13 was
Innermost layer 10 made of nylon 11 (wall thickness 0.2 mm)
And an intermediate layer 12 (thickness 0.1 mm) made of polybutylene naphthalate and an outer layer 14 (thickness 0.6 mm) made of nylon 11.

(Comparative Example 14) The tube of Comparative Example 14 was
Innermost layer 10 made of polyvinylidene fluoride (thickness 0.1
mm) and a mixture of polyvinylidene fluoride, polybutylene terephthalate, and thermoplastic polyurethane in a ratio of 4/4/1 (volume ratio) (thickness: 0.05 mm).
And an intermediate layer 12 made of polybutylene terephthalate
(Thickness 0.1 mm), an adhesive layer 13 made of thermoplastic polyurethane (thickness 0.05 mm), and an outer layer 14 made of nylon 11 (thickness 0.7 mm).

(Comparative Example 15) The tube of Comparative Example 15 was
Innermost layer 10 made of polyvinylidene fluoride (thickness 0.1
mm) and an intermediate layer 1 made of polybutylene naphthalate.
2 (wall thickness 0.1 mm) and outer layer 1 made of nylon 11
4 (wall thickness 0.8 mm).

The transmission speed and the breaking resistance of the tubes obtained in Comparative Examples 1 to 15 were measured. Tables 3 and 4 show the test results along with the configuration of the tubes of each comparative example.
Shown in

[0146]

[Table 3]

[0147]

[Table 4]

Hereinafter, based on the results in Tables 1 to 4, the fuel barrier properties and the breakage resistance of the tubes obtained in the examples are compared with those of the tubes obtained in the comparative examples. I do.

As is clear from comparison of the respective tables, it can be seen that in Comparative Examples other than Comparative Example 13, the fuel permeation rate was large and the fuel barrier properties were inferior.

In particular, the general polyester resins shown in Comparative Examples 4 to 7 showed transmission several tens times higher than the multilayer tube using the polybutylene naphthalate resin shown in the Examples. It was found that the fuel barrier properties of polybutylene naphthalate were remarkably excellent.

From the comparison result between the tube of Example 1 and the tube of Comparative Example 12, the following can be understood.

The tube of Comparative Example 12 was composed of the adhesive layers 11 and 1
Since it has No. 3, it has good breaking resistance, but has a high fuel permeation rate, and is extremely inferior in fuel barrier properties to both Fuel C and alcohol mixed fuel.

Therefore, as a material of the intermediate layer 12, polybutylene naphthalate is remarkably superior to polybutylene terephthalate.

From the comparison results between the tubes of Examples 1 to 7 and the tube of Comparative Example 13, the following can be understood.

Although the tubes of Examples 1 to 7 and the tube of Comparative Example 13 do not differ greatly in the fuel barrier property, the tube of Comparative Example 13 is extremely poor in breaking resistance. Therefore, when the adhesive layers 11 and 13 are provided, the breaking resistance can be remarkably improved.

Further, the following can be understood from the comparison result between the tube of Example 8 and the tube of Comparative Example 14.

The tube of Comparative Example 14 has a higher permeation speed than the tube of Example 8, and is inferior in fuel barrier properties by several tens of times to both Fuel C and alcohol mixed fuel. Therefore, in order to enhance the fuel barrier property, polybutylene naphthalate is significantly superior to polybutylene terephthalate as the material of the intermediate layer 12.

The following results can be seen from the comparison result between the tube of Example 8 and the tube of Comparative Example 15.

Although there is no great difference in the fuel barrier property between the tube of Example 8 and the tube of Comparative Example 15,
The tube of Comparative Example 15 has extremely poor fold resistance. On the other hand, the tube of Example 8 has significantly improved breaking resistance.

Therefore, the provision of the adhesive layers 11 and 13 can greatly improve the fold resistance.

[0161]

According to the present invention, sufficient fuel barrier properties and chemical resistance can be exhibited even with a methanol-mixed fuel as an alternative fuel or an existing gasoline fuel. In addition, it is possible to provide a fuel transfer tube which can improve the breaking resistance and is particularly suitable for a fuel tube of a transportation vehicle such as an automobile. Furthermore, since a fluorine resin or polyamide resin is used as the material of the innermost layer, it is excellent in hydrolysis resistance and fuel oil resistance, does not deteriorate with time, and is more durable than conventional fuel transfer tubes. Can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an embodiment of a fuel transfer tube according to the present invention.

FIG. 2 is a cross-sectional view of another embodiment of the fuel transfer tube of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fuel transfer tube 10 Innermost layer 11 Adhesive layer 12 Intermediate layer 13 Adhesive layer 14 Outer layer

Continued on the front page (72) Inventor Toshiaki Kasazaki 172, Ikezawa-cho, Yamatokoriyama-shi, Nara Nita Co., Ltd. (72) Inventor Eiji Inoue 172, Ikezawa-cho, Yamatokoriyama-shi, Nara Nita Co., Ltd. (56) References JP-A-6-23930 (JP, A) EP-A-542185 (EP, A1) (58) Fields investigated (Int. Cl. ⁷ , DB name) B32B 1/00-35 / 00 F16L 9/00-11/24

Claims (19)

(57) [Claims] 1. An innermost layer made of one selected from the group consisting of a fluorine-based resin and a polyamide-based resin , and a polybutylene surrounding the innermost layer and having an intrinsic viscosity of 0.9 to 1.5.
A fuel transfer tube having an intermediate layer made of a naphthalate resin, an outer layer made of a thermoplastic resin or a thermoplastic elastomer, and an adhesive layer formed between the innermost layer and the intermediate layer. 2. The fuel transfer tube according to claim 1, wherein the thickness of the intermediate layer is 5 to 20% of the total thickness of the intermediate layer. 3. The method according to claim 1, wherein the innermost layer is made of a polyamide resin, and the adhesive layer is selected from the group consisting of a thermoplastic polyurethane, a polyether block amide, a polyester block amide, a modified polyolefin, a polyester copolymer and a polyester elastomer. 2. The fuel transfer tube according to claim 1, comprising at least one of the following. 4. The innermost layer is made of a polyamide resin, and the adhesive layer is made of an adhesive resin containing a polyamide resin and a crystalline polyester or a polyester elastomer, wherein the polyamide resin and the crystalline polyester or The fuel transfer tube according to claim 1, wherein a mixing ratio with the polyester elastomer is in a range of 70/30 to 30/70 by volume. 5. The adhesive resin further includes an epoxy compound containing a glycidyl group or a glycidyl ether group, an acid anhydride, an oxazoline group, a carboxylic acid group, an isocyanate group, (meth) acrylic acid or (meth) acrylic acid. 5. The fuel transfer tube according to claim 4, wherein a compatibilizer selected from the group consisting of a compound having an ester skeleton, a compound having an amino group and a hydroxyl group is melt-mixed. 6. The innermost layer is made of a fluororesin, and the adhesive layer is made of at least one selected from the group consisting of a fluororesin, a soft fluororesin and a fluororubber, a crystalline polyester resin and a polyester. 2. The fuel transfer tube according to claim 1, comprising an adhesive resin containing at least one selected from the group consisting of a series elastomer. 7. The method according to claim 1, wherein the innermost layer is made of a fluororesin, and the adhesive layer is at least one selected from the group consisting of a fluororesin, a soft fluororesin, and a fluororubber;
An adhesive resin containing at least one selected from the group consisting of a crystalline polyester resin and a polyester elastomer, and the mixing ratio is 8 by volume.
2. The fuel transfer tube according to claim 1, wherein the range is 0/20 to 20/80. 8. The adhesive resin further includes an epoxy compound containing a glycidyl group or a glycidyl ether group, an acid anhydride, an oxazoline group, a carboxylic acid group, an isocyanate group, (meth) acrylic acid or (meth) acrylic acid. 7. The fuel transfer tube according to claim 6, wherein a compatibilizer selected from the group consisting of a compound having an ester skeleton, a compound having an amino group and a hydroxyl group is melt-mixed. 9. The fuel transfer tube according to claim 1, wherein the thermoplastic resin forming the outer layer is one selected from the group consisting of polyamide and polyester elastomer. 10. The fuel transfer tube according to claim 1, wherein a second adhesive layer is further provided between the intermediate layer and the outer layer. Wherein said second adhesive layer, thermoplastic polyurethane, polyether block amide, claim 10 comprising at least one member selected from the group consisting of polyester block amides, modified polyolefins, polyester copolymers and polyester elastomer A tube for transferring fuel according to the above. 12. The second adhesive layer contains (A) a polyamide resin and (B) at least one selected from the group consisting of a polyester elastomer and a crystalline polyester. the mixing ratio of B) is according to claim 10 in the range of 70 / 30-30 / 70 by volume
A tube for transferring fuel according to the above. 13. The second adhesive layer further includes an epoxy compound containing a glycidyl group or a glycidyl ether group, an acid anhydride, an oxazoline group, a carboxylic acid group, an isocyanate group, (meth) acrylic acid or (meth) acrylic acid. The fuel transfer tube according to claim 10, wherein a compatibilizer selected from the group consisting of a compound having an acrylate ester skeleton, a compound having an amino group and a hydroxyl group is melt-mixed. 14. A gasoline fuel permeation rate of 0.01
The fuel transfer tube according to claim 1, which has a gasoline permeation rate of 5 g / m2 / day or less, wherein the gasoline fuel permeation rate is a value determined under the following conditions: a tube having an outer diameter of 8 mm, an inner diameter of 6 mm, and a length of 1000 mm. A gasoline fuel obtained by mixing reagent-grade toluene and reagent-grade isooctane at a volume ratio of 1 to 1 is sealed therein.
It is left in an oven at 0 ° C., the time-dependent change in weight loss is determined, and the value is obtained by dividing the amount reduced per day by the outer surface area of the tube. 15. The fuel transfer tube according to claim 1, wherein the permeation rate of the methanol-containing gasoline fuel is 2.0 g / m 2 / day or less, wherein the permeation rate of the methanol-containing gasoline fuel is obtained under the following conditions. A gasoline-containing gasoline fuel obtained by mixing the gasoline fuel and methanol according to claim 11 in a volume ratio of 85 to 15 is sealed in a tube having an outer diameter of 8 mm, an inner diameter of 6 mm, and a length of 1000 mm. , Leave this in an oven at 60 ° C,
This is a value obtained by determining the change over time in weight loss and dividing the amount of loss per day by the outer surface area of the tube. 16. The fuel transfer tube according to claim 1, wherein the thickness of the intermediate layer is 5 to 20% of the total thickness of the tube. 17. The fuel transfer tube according to claim 1, wherein the thickness of the adhesive layer is 2 to 10% of the thickness of the entire tube. 18. The fuel transfer tube according to claim 1, wherein the thickness of the entire tube is 5 to 20% of the outer diameter of the tube. 19. The overall thickness of the tube is 5 to 20% of the outer diameter of the tube, the thickness of the intermediate layer of the tube is 5 to 20% of the wall thickness of the tube, and the first and second tubes have the same thickness.
Fuel transfer tube according to claim 10, wherein the thickness of the adhesive layer is 2-10% of the wall thickness of the entire tube.