JP3345672B2 - 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 tube for transferring alcohol, gasoline, and a mixed fuel thereof (hereinafter referred to as a fuel transfer tube).

[0002]

2. Description of the Related Art As this kind of fuel transfer tube,
Tube already made of metal, nylon 11,
12 and other tubes have been proposed.

In recent years, in recent years, in automobiles, tanks have been made of resin in order to reduce the weight of the vehicle and to ensure the degree of freedom in design, and in Europe and the United States, resin tubes are often used in piping systems.

However, the above-mentioned tube has the following two problems. The impermeability of alcohol and gasoline is low, and regulations on pollution are strict, which can be a serious problem nowadays. Because of its large linear expansion coefficient, the amount of expansion and contraction due to temperature changes is large.For this reason, when used as a fuel pipe for automobiles, the expansion of the tube interferes with other parts and causes fuel leakage, or the tube shrinks. It can cause disconnection from the connection or lead to a very dangerous situation.

[0005] Incidentally, using the above-described tubes, a test for individually transferring alcohol and gasoline (gasoline permeability test and alcohol permeability test shown below) and a test for confirming the linear expansion coefficient were carried out. I tried. Hereinafter, the method of this test is shown, and the test results are shown in Table 1. [Permeability test] Tube 1000 with 8 mm outer diameter and 6 mm inner diameter
Each sample solution is sealed in mm and left at room temperature of 23 ° C.
The time course of weight loss was followed.

[0006] The value of weight loss is converted into time per day,
This value is referred to as permeability (transmission speed: g / m ^Two/ Day)
And (1) Sample liquid Regular gasoline: Obtained at gas stations in the market
The one that can be used was used as it is.

Huell C: A mixture of reagent grade toluene and reagent grade isooctane at a volume ratio of 1: 1 was used.

Methanol: Reagent grade methanol was used as is. FAM15: 8 parts by volume of Fuel C and methanol
A mixture of 5 to 15 was used. (2) Evaluation criteria Regular gasoline: 0.01 g / m ² / day or less Huell C: 0.06 g / m ² / day or less Methanol: 6.5 g / m ² / day or less FAM15: 2.6 g / m ² / day [Test for confirming the coefficient of linear expansion] First, five tube test pieces (100 mm × 5) were annealed at 100 ° C. × 2 hours to remove stress. After returning to room temperature, the temperature was raised again to 100 ° C., and the length at a high temperature (100 ° C.) after 2 hours was measured to determine the difference from the length at room temperature.

Evaluation criteria 5.0 × 10 ⁻⁵ mm / mm / ° C. or less [Test results]

[0010]

[Table 1]

[0011]

Therefore, according to the present invention, a fuel transfer tube which is excellent in impermeability to alcohol, gasoline and a mixed fuel thereof and has a small amount of expansion and contraction with respect to a change in ambient temperature. The task is to provide

[0012]

According to a first aspect of the present invention, there is provided a fuel transfer tube in which an inner layer and an outer layer are made of a polyamide resin, and a polyester liquid crystal polymer and a polyester resin are provided between the inner layer and the outer layer. Wherein the polyester-based liquid crystal polymer is oriented in the length direction of the tube in the intermediate layer.

(Invention of Claim 2) A fuel transfer tube according to the present invention relates to the invention of Claim 1, wherein these tubes are bonded to each other between an inner layer and an intermediate layer and between an intermediate layer and an outer layer. The adhesive layer is provided. (Regarding Liquid Crystal Polymer) The liquid crystal polymer used in the present invention may be selected based on the melt viscosity according to the processing temperature of the polyester resin. The liquid crystal polymer includes an aromatic dicarboxylic acid component and an aromatic diol component. Polyesters obtained by polycondensation of aromatic hydroxycarboxylic acids; copolymerized polyesters of the above two polyesters; and thermotropic ones such as copolyesters of these polyesters and polyethylene terephthalate. Can be.

For example, rod run manufactured by Unitika, Vectra manufactured by Polyplastics, Novaculate manufactured by Mitsubishi Kasei, Idemitsu LCP manufactured by Idemitsu Petrochemical Co., Ltd., Ueno LCP manufactured by Ueno Pharmaceutical Co., Ltd. You can arbitrarily select from among them. (Regarding Polyamide Resin) As the polyamide-based resin used in the present invention, a high-molecular-weight linear polyamide is used. The polyamide may be a homopolyamide, a copolyamide or a blend thereof.

Such polyamides include, for example, the following amide repeating units: —CO—R ¹ —NH— (1) or —CO—R ² —CONH—R ³ —NH (1) A homopolyamide having an amide repeating unit of (2) wherein each of R ¹ , R ² and R ³ represents a linear alkylene group;
Copolyamides or blends thereof can be mentioned. In consideration of the gas barrier properties against oxygen, carbon gas, and the like, the number of amide groups per 100 carbon atoms in the polyamide resin used in the present invention is 3 to 30, especially 4 to 25. It is preferred to use polyamides, copolyamides or blends thereof. Specific examples of suitable homopolyamides include polycapramide (nylon 6), poly-ω-aminoheptanoic acid (nylon 7), poly-ω-aminononanoic acid (nylon 9), polyundecaneamide (nylon 11), and polylaurin lactam. (Nylon 12), polyethylene diamine adipamide (nylon 2,6), polytetramethylene adipamide (nylon 4,6), polyhexamethylene adipamide (nylon 6,6) polyhexamethylene sebacamide (nylon 6,10) polyhexamethylene dodecamide (nylon 6,12) polyoctamethylene adipamide (nylon 8,6), polydecamethylene adipamide (nylon 1
0,6), polydecamethylene sebacamide (nylon 1
0, 10) and polidodecamethylene dodecamide (nylon 12, 12).

Examples of copolyamides suitable for use in the present invention include caprolactam / laurin lactam copolymer, caprolactam / hexamethylene diammonium adipate, laurin lactam / hexamethylene diammonium adipate. Copolymer, hexamethylene diammonium adipate / hexamethylene diammonium sepate copolymer, ethylene diammonium adipate / hexamethylene diammonium adipate copolymer, caprolactam / hexamethylene diammonium adipate / hexamethylene diammonium sepate polymer And the like. The polyester resin used (for the polyester resin) is obtained by ordinary melt polycondensation. That is, it refers to a resin produced by condensing a dicarboxylic acid component and a glycol component under appropriate reaction conditions in the presence of a catalyst.

The following are specific examples of each component, but the dicarboxylic acid and glycol components used are not particularly limited.

Examples of the dicarboxylic acid used include terephthalic acid, isophthalic acid, orthophthalic acid and 2,6-naphthalenedicarboxylic acid. Others
Aliphatic and alicyclic dicarboxylic acids include succinic acid, adipic acid, sebacic acid, 1,3-cyclopentanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid,
Examples thereof include 1,3 cyclohexanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid.

The glycol components to be reacted with these dicarboxylic acid components are the following aliphatic and alicyclic glycols, and specifically, ethylene glycol / 1,2-
Propylene glycol ・ 1,3-propanediol ・
1,4-butanediol, 1,6-hexanediol, diethylene glycol, triethylene glycol, p-
Xylylene glycol and the like can be mentioned.

Other polyethers such as polyethylene glycol, polypropylene glycol and polytetramethylene glycol may be used as the third component.

Further, as the kind of the polyester resin used in the present invention, in addition to the above-mentioned resin, a polyester elastomer derived from each of the above-mentioned components and a so-called modified polyester resin having an adhesive property may be used.

When a modified polyester having an adhesive property is used, the adhesive layer in the construction of the multilayer molded tube is not necessarily required. (Regarding the Structure of the Adhesive Layer) As the resin used for the adhesive layer, a resin layer laminated during co-extrusion molding, that is, a mixture of a liquid crystal polymer and a polyester resin as an intermediate layer and a polyamide resin as an innermost and outermost layer are directly heated. It is not particularly limited as long as it has a fusibility. For example, one or a mixture of two or more of thermoplastic polyurethane, polyether block amide, modified polyolefin, polyester copolymer, and polyester elastomer is used. preferable. Further, a mixture obtained by melt-mixing the above adhesive resin with a polyamide resin and a polyester resin can also be suitably used.

[0023]

Embodiments of the present invention will be described below.

In the tubes of Examples 1 to 4, as shown in FIG. 1, the inner layer 1 and the outer layer 5 are made of a polyamide resin, and the liquid crystal polymer 30 and the polyester resin are interposed between the inner layer 1 and the outer layer 5. , And the inner layer 1 and the intermediate layer 3 and the intermediate layer 3 and the outer layer 5 are adhered by the adhesive layers 2 and 4. Here, the liquid crystal polymer 30 in the intermediate layer 3 is used.
Is fibrillated and oriented along the length of the tube, but the fibrils may be homodisperse or nondisperse.

When the melt viscosity of the polyester resin is higher than that of the liquid crystal polymer 30, the fibrils are easily formed uniformly. When the melt viscosity of the polyester resin is lower than that of the liquid crystal polymer 30, the polyester resin tends to be unevenly dispersed.

The tubes of all the above-mentioned examples are manufactured by co-extrusion molding, and specific types of polyamide resin, polyester resin and liquid crystal polymer 30, and the mixing ratio of polyester resin and liquid crystal polymer 30 (numerical% in parentheses) ), And the thickness of each layer is as shown in Table 2. Hereinafter, the method of mixing the mixture will be described, and the test results of the present invention obtained by the same method as the test method described in the section of the prior art will be shown in Table 2. [Mixing method] A liquid crystal polymer and a polyester resin are supplied to an extruder in the form of a mixture. This mixture may be a dry blend of the two or a melt blend. Dry blending can be performed using, for example, various mixers such as a ribbon blender, conical blender, and Henschel mixer, while melt blending is performed using a single-screw or twin-screw extruder, a kneader, a Banbury mixer, a roll, and the like. Can be done. 〔Test results〕

[0027]

[Table 2]

Comparison between Table 2 and Table 1 shows that the fuel transfer tube of the present invention is more resistant to alcohol, gasoline and their mixed fuels than the tube described in the section of the prior art. It can be seen that the permeability is excellent and the amount of expansion and contraction is small with respect to the change in the ambient temperature.

The mixing ratio of the liquid crystal polymer is 10 to 90.
% Can be adopted, and 30 to 70% is preferable.

[0030]

The present invention has the following effects since it has the above-described configuration.

From the contents of the above-mentioned examples and the like, it was possible to provide a fuel transfer tube having excellent impermeability to any of alcohol, gasoline, and a mixed fuel thereof and having a small amount of expansion and contraction with respect to a change in ambient temperature. .

[Brief description of the drawings]

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

[Explanation of symbols]

 Reference Signs List 1 inner layer 2 adhesive layer 3 intermediate layer 4 adhesive layer 5 outer layer 30 liquid crystal polymer

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takushi Ando 172 Ikezawa-cho, Yamatokoriyama-shi, Nara Prefecture Nita Plant Inside Nara Plant (72) Inventor Tsutomu Nishino 1300-45 Yahata, Nabari-shi, Mie Nitta Moor Co., Ltd. Inside the Nabari Plant (72) Inventor Yuji Nakabayashi 1300-45 Nitta Moore, Nabari City, Mie Prefecture Inside the Nabari Plant (72) Inventor Tan Nakatsu 1300-45 Yahata, Nabari City, Mie Prefecture Nitta Moor Co., Ltd. Inside the factory (56) References JP-A-57-25354 (JP, A) JP-A-63-112652 (JP, A) JP-A-63-241068 (JP, A) JP-A-5-220912 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B32B 1/00-35/00 F16L 9/00-9/22 F16L 11/00-11/24

Claims (2)

(57) [Claims] An inner layer and an outer layer are composed of a polyamide resin, and an intermediate layer composed of a mixture of a polyester liquid crystal polymer and a polyester resin is provided between the inner layer and the outer layer. A tube for transferring fuel, wherein the liquid crystal polymer is oriented in the length direction of the tube. 2. The fuel transfer tube according to claim 1, wherein an adhesive layer is provided between the inner layer and the intermediate layer and between the intermediate layer and the outer layer, the adhesive layer bonding these layers to each other.