JPS6291317A - Synthetic resin made filler pipe - Google Patents

Abstract

PURPOSE:To prevent firing due to static electricity and deformation of a pipe, by constituting the pipe such that an inlet pipe part inserts an olefine polymer molded article, adding an inorganic filling material and having the same quality to the main unit, to be welded, in the case of the captioned pipe for supplying fuel to an automobile. CONSTITUTION:An olefine system polymer of the same quality to a filler pipe 3, for instance, an injection molding article is formed by adding an inorganic filling material of aluminum or the like to polyethylene and inserted to an inlet pipe part 2. Next the filler pipe 3 is formed by ordinary hollow molding. By this constitution, firing of fuel due to static electricity and deformation of the pipe can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a filler pipe made of synthetic resin that has improved corrosion resistance and does not ignite fuel due to static electricity. More specifically, it relates to a synthetic resin filler pipe obtained by insert molding or post-pressure welding an injection molded product made by adding an inorganic compound to an olefin polymer made of the same material as the main body to the inlet pipe part. The object of the present invention is to provide a filler pipe made of synthetic resin which has improved corrosion resistance and which does not cause ignition of fuel due to static electricity.

Currently, metal is used for filler pipes in automobiles, but due to its corrosion resistance, light weight, and freedom of shape,
The development of filler pipes made of hollow molded synthetic resin is in progress.

Conventionally, a one-touch Zt has been used for fuel supply (1), and the inlet I/pipe needs to have high rigidity. In addition, in order to attach the device to the fuel backflow preventer 1 within the fuel supply 1, the inlet pipe part has a complicated shape, and it is impossible to form it integrally by blow molding.

For this reason, consideration has been given to inserting metal inlets and pipes. However, if a metal insert is used, the static electricity generated by the pump and meter when refueling is likely to accumulate and become a source of ignition, so safety precautions must be taken.
- It is necessary to take the ground, making the shape complicated. Furthermore, there were other problems such as an increase in the number of parts.

For this reason, we considered forming the inlet/pipe part by injection molding and inserting it when hollow molding the filler pipe, or welding it in post-processing, but the synthetic resin alone lacks rigidity, and the one-touch cap There were problems such as the lid becoming deformed by the nails and the lid coming off.

Departure-I! From the above points, the present invention provides a filler pipe made of synthetic resin that does not have these drawbacks (problems), that is, not only does not ignite the fuel due to static electricity, but also does not deform the inlet pipe section. That's true.

According to the present invention, these problems can be solved by insert molding or insert molding an injection molded product made of the same olefin polymer as the main body with an inorganic compound added to the inlet pipe part. This can be solved by using a synthetic resin filler pipe that can be obtained by welding in post-processing. The present invention will be explained in detail below.

(A) Olefin polymer The olefin polymer used for manufacturing the inlet I/pipe part and filler pipe of the present invention includes an It polymer of ethylene, a homopolymer of propylene, and a copolymer of ethylene and propylene. Examples include copolymers of ethylene and/or propylene with other α-olefins having at most 12 carbon atoms (polymerization ratio of at most 20% by weight). These olefins In the case of ethylene-11 polymers and copolymers mainly composed of ethylene, the melt index (according to JIS K-8760) is
Measured at 0°C and a load of 2.18Kg, below r
M, T, J) or propylene homopolymers and propylene-based copolymers, the melt flow index (according to JTS K-8758,
Measured under the conditions of a temperature of 230°C and a load of 2.18 Kg, hereinafter referred to as r MFTJ ) for filler pipes is generally 5.0 g / 10 minutes or less, and 0.
001 to 5.0 g/10 min is preferable, especially 0.0
05 to 3.0 g/10 minutes is suitable. Also, in the inlet pipe, A, ■, or MFI is usually 0.5 to 5.
0 g/10 minutes, preferably 1.0 to 50 g/10 minutes, particularly preferably 1.0 to 30 g/10 minutes. Inlet pipe M, 1. Alternatively, if the MFI is less than 0.5 g/10 minutes, moldability is not good. On the other hand, M of the filler pipe and inlet pipe, 1. If the MFI exceeds the -E limit, the resulting filler pipe will have low rigidity, which is not preferable. Furthermore, the density is 0.935-0.980 g
/cm'' ethylene homopolymer or copolymer of ethylene with a small amount of the above α-olefin, propylene homopolymer, or random or block copolymer of propylene with ethylene and/or other α-olefins is desirable. .

These olefinic polymers are produced by using a catalyst system (so-called Ziegler catalyst) obtained from a transition metal compound and an organoaluminium compound, and by supporting 1 μm of a chromium-containing compound (e.g., chromium oxide) on a carrier (e.g., silica). It can also be obtained by copolymerizing or copolymerizing olefins using the resulting catalyst system (so-called Phillips catalyst).

(B) Inorganic compound (inorganic filler) The inorganic compound used to manufacture the inlet pipe of the present invention is widely used as an inorganic filler in the fields of synthetic resins and rubber. These inorganic fillers are preferably inorganic compounds that do not react with oxygen and water and do not decompose during kneading and molding. The inorganic fillers include metals such as aluminum, copper, iron, lead and nickel, oxides of these metals and metals such as magnesium, calcium, barium, zinc, zirconium, molybdenum, silicon, antimony and titanium, and their water. hydrate (hydroxide), sulfuric acid fJ! compounds such as carbonates, silicates,
It is broadly classified into these double salts and mixtures thereof. Typical examples of the inorganic filler include the metals mentioned above, aluminum oxide (alumina), its hydrate, calcium hydroxide,
Magnesium oxide (magnesia), magnesium hydroxide, lead oxide (zinc oxide), red lead and lead liquefaction such as 1, 'rJWa magnesium, calcium carbonate,
j17. Base M carbon W magnesium 11, white carbon,
Asbestos, mica, talc, glass fiber, glass powder, glass peas, clay, silica, silica, Wollastonite I, iron oxide, antimony oxide, titanium oxide (titania), lithopone, pumice powder, aluminum sulfate (gypsum, etc.) , zirconium silicate, -1 zirconium oxide, Wm barium, dolomite, -1 molybdenum sulfide, and iron sand. Among these inorganic fillers, those in powder form preferably have a diameter of 1 mm or less (preferably 0.5 mm or less). In addition, for fibrous materials, the diameter is 1 to 500.
microns (preferably 1 to 300 microns) and length y of 0.1 to 6 mm (preferably 0.1 to 5 m).
m) is desirable. Furthermore, the flat plate has a diameter of 2
mm or less (preferably 1 mm or less).

Among these inorganic fillers, glass fiber, mica, talc, etc. are suitable for increasing the rigidity of the filler pipe obtained, and glass fiber is particularly suitable.

(C) Inlet pipe The inlet pipe of the present invention is made of a composition consisting of the above-mentioned olefin polymer and an inorganic compound (inorganic filler) (the M+ composition ratio of the inorganic compound is usually 5 to 50 parts ↑- %) by injection molding. When carrying out this injection molding, the molding temperature is generally 180 to 3.
00°C, preferably 220-280°C.

(D) Manufacture of Filler Pipe The filler pipe of the present invention can also be manufactured by inserting in advance the inlet pipe section III as described in 1- below and by blow molding, which is commonly performed. At this time, the molding temperature is generally 1
The temperature is 70 to 230°C, especially 180 to 220°C. At this time, check the inlet pipe section1.
A preferred method is to heat it to 00 to +20'C, fix it to a blowing pin during blow molding, cover the inlet pipe with a parison, and insert it into the inlet by holding it in place with the parison when the shape is tightened. It will be implemented.

Still another method is a welding method. This girl,
Welding is done by applying a hot plate and heating the welded part between the inlet pipe and the main body to melt it, and then removing the hot plate and welding using butt welding, which is crimped, or spin welding, which uses rotational friction to melt the welded part. It can also be manufactured by

It should be noted that when manufacturing the filler pipe of the present invention, the olefin polymers used for the inlet pipe section and the filler pipe body do not necessarily have to be the same, but they may be of the same type (for example, when using ethylene polymers,
It may be a homopolymer or a copolymer, but in both cases an ethylene polymer is used.

(E) Filler Pipe Hereinafter, one example of the filler pipe of the present invention will be described with reference to the drawings.

FIG. 1 is a side view of the entire filler pipe, and FIG. 2 is a longitudinal sectional view of the inlet pipe section. In these figures, ■ is a filler pipe, and 2 is an inlet pipe section. Further, 3 is a hollow-molded filler pipe body. Furthermore, 4 is the first entry into the fleet, and 5
is a fuel backflow prevention 11° valve.

・Ni and Comparison The present invention will be explained in more detail with reference to Examples below.

Example I High-density ethylene-based polymer (M, 1.2.0 g/10 min) with a density of 0.945 g/c rn', 79% by weight, average diameter of 12 microns and average length An inlet pipe section was manufactured by injection molding a composition consisting of 20% by weight of glass fibers having a diameter of 3 mm and 11% of carbon plastic (average particle size: 30 microns) at 220°C. The inlet pipe section obtained in this way was inserted into an inserter so that the density was 0. ! 3
A composition consisting of 88% by weight of a high density ethylene polymer (M, 1.0.05g/710 min) having a density of 46 g/c rn" and 1% by weight of the carbon black was prepared at 20% by weight.
Blow molding was carried out at 08C to produce a filler pipe (average wall thickness 3.8+nm, length 380mm, gasoline inlet diameter 55mm, total weight 58Qg).

The flexural modulus of the composition used for the inlet pipe section (measured according to JIS K-7203) is 28.
．． 000Kg/cm', and the flexural modulus of the composition used for the filler pipe is 12,000Kg/cm'.
It was rr.

Example 2 Instead of the high-density ethylene polymer used to manufacture the inlet pipe section in Example 1, a propylene-ethylene block copolymer with an ethylene content of 10% by weight (MF1 1.5 g/lO A composition similar to that of Example 1 was prepared except that the following composition was used. This composition was injection molded at 230° C. to produce an inlet pipe section having the same shape and size as in Example 1.

In addition, instead of the high-density ethylene polymer used to manufacture the filler pipe in Example 1, a propylene-ethylene block copolymer (MFI O, 7g, 710 minutes) with an ethylene content of 8.8% by weight was used. A composition similar to that of Example 1 was produced except that . A filler pipe similar to that in Example 1 was manufactured by blow molding this composition at 210°C. The flexural modulus of the composition used for the inlet pipe section is 31.000, and the f! of the filler pipe is 31.000. lJ
The flexural modulus of the composition used for construction was 13,000 kg/
It was crrf.

Regarding the charging when a metal fitting is attached to the filler pipe obtained in Example 1 and gasoline is supplied into the tank, the temperature is 28 to 32°C and the relative humidity is 40 to 43%.
The electrostatic voltage of metal fittings under the conditions of is 0 when there is no ground.
．． It was 7-8 KV. On the other hand, if earthed, O
It was KV.

The synthetic resin filler pipe of the present invention exhibits the following effects including its manufacturing process.

(1) There is no ignition of fuel due to static electricity.

(2) It is lighter than metal.

(3) No corrosion due to air and moisture.

(4) There is freedom in shape.

(5) The inlet pipe is not deformed.

(6) It can be manufactured relatively easily.

(7) High rigidity (flexural modulus) - 1 (18,000K)
g/cm m' or more).

[Brief explanation of drawings]

FIG. 1 is a side view of the entire filler pipe, and FIG. 2 is a longitudinal sectional view of the vicinity of the inlet pipe. l...Filler pipe 2...Inlet pipe section 3...Filler pipe body 4...Fuel inlet 5...Fuel backflow prevention valve

Claims (1)

[Claims] A synthetic resin filler pipe obtained by insert molding or post-processing welding an injection molded product made by adding an inorganic compound to the same olefin polymer as the main body to the inlet pipe part.