JPS6278046A - Hollow vessel made of synthetic resin - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a synthetic resin hollow container having a structure suitable for large containers. More specifically, it relates to a synthetic resin hollow container obtained by extruding the side plate of the synthetic resin hollow container into a tubular body, compression molding the top plate and base plate, and converting these into a body. The object of the present invention is to provide a synthetic resin hollow container having a structure particularly suitable for large containers such as drums.

It is extremely effective when aiming to improve durability and VJ performance. Various types of synthetic resin containers are already in use in Europe and the United States. In Japan as well, trials are rapidly progressing to convert closed drums, which are currently mostly made of metal, to resin.

These synthetic resin drums are required to have the same handling properties as metal drums.

However, if the shape is shaped like a metal drum in order to maintain the same handling properties as metal drum cans, synthetic resin cans can be made using the blow molding method. Because it is A-shaped, there is a difference in wall thickness between the parting direction and its reconnaissance force direction, especially in the upper and lower corners and in the direction perpendicular to the parting of the handling 4fl! Has consideration been given to using a variable capacitor in the circumferential direction for the molding mount to increase the thickness of the IH holder, and moving the position of the IH holder for the shape of the product? None of these methods have reached the point where a synthetic resin hollow container with a uniform wall thickness distribution has been obtained.In order to satisfy the required strength against impact and stacking, the weight of the product must be increased.

Therefore, the molding device also requires expensive bending equipment such as a circumferential variable capacitor, resulting in high costs.

[Long time] Problem 1 is intended to be solved, the present invention solves these problems (disadvantages)
In other words, it is possible to reduce wasteful wall thickness as much as possible and produce a hollow container with a uniform wall thickness distribution at a low cost.

According to the present invention, these problems can be solved by extrusion molding the side plate of the synthetic resin hollow container into a tubular body, and compression molding the top plate and base plate. This problem can be solved by a synthetic resin hollow container obtained by integrating these. The present invention will be explained in detail below.

The tubular body of the synthetic resin hollow container of the present invention is manufactured by extrusion molding.

As the synthetic resin used to manufacture the tubular body, a olefin-based polymer is preferably used;
(The mass is less than 0.835 g/cm').
- A copolymer with an olefin (usually having 3 to 12 carbon atoms and a copolymerization ratio of at most 15% by weight and 4.7%) is preferred.

The molecular weight of these ethylene narrow polymers and copolymers of ethylene and α-olefin differs depending on the container size and capacity, but the melt flow index (JIS
The temperature is 190°C and the load is 21.6Kg.
For example, in the case of a container with a capacity of 200 liters, it is generally 5.0 g/10 minutes or less, and 4.
．． 0g/10 minutes or less is the best, especially 3.5g/10 minutes or less.
A duration of 10 minutes or less is suitable. In addition, in the case of a container with a capacity of 20, the HLMFR is usually 5 to 50 g/
10 minutes, preferably 10 to 50 g/10 minutes, particularly preferably 10 to 40 g/10 minutes.

This tubular body is formed into a tubular body having a uniform wall thickness by extrusion molding in the same manner as in the production of pipes in the field of olefin polymers (in particular, the above-mentioned ethylene polymers and ethylene copolymers). At this time, the extrusion temperature is generally 190°C to 240°C. The diameter of the tubular body varies depending on the hollow container to be manufactured, the size and shape of the container, but is usually 200 to 700 mn+. Also, the wall thickness varies depending on the size and shape of the container, but
Generally it is 2 to 6 mm. The tubular body thus obtained is cut according to the size of the hollow container and used.

The top plate and base plate of the present invention can be manufactured by pressing and molding, which is generally practiced in the field of olefin polymers. This method can also be used with synthetic resins that are difficult to mold using injection molding methods and have poor flowability. The top plate and base plate can be manufactured using this method by placing a lump of synthetic resin melted in an extruder or the like into a press mold and compressing it. At this time, the compression molding temperature is usually 190 to 240°C. The thickness and diameter of the top plate and bottom plate portions thus obtained may be determined as appropriate depending on the size of the hollow container.

By integrating the tubular body obtained as described above with the top plate and the bottom plate, the hollow container of the present invention can be manufactured.
I can do that.

To integrate these, the spin weld method uses rotation to preheat the welded parts, the friction weld method uses vibration to preheat the welded parts, and the
There is a pad welding method in which the material is preheated to 180 to 250° C. and then welded by applying pressure.

Of these methods, the spin weld method and the frikken well F method have the disadvantage of causing flaking, so the hunt welding method is preferred.

Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a perspective view of a hollow container of the present invention. FIG. 2 is a longitudinal section H of the container. In this drawing, the top plate 2 and the base plate 3 are heat-welded to the side plate 4 of the extruded pipe at the attachment portion 78. 3 is a longitudinal sectional view of each part of the hollow container whose longitudinal sectional view is shown in FIG. 2 before welding. Since the lateral roots 4 are extruded pipes, they are uniform and can be cut to any thickness. The top plate 2 and tty 63 are formed by stamping.
In order to manufacture hollow containers with low impact strength when manufactured by injection molding, olefinic polymers (for example, the above-mentioned ethylene 7 Homopolymerization (
4. Using a copolymer of ethylene and α-olefin) also requires higher costs for the mold and molding equipment compared to the compression molding method.

Furthermore, in order to reduce costs, as shown in the vertical cross-sectional view in FIG. 4, the molds for the top plate 2 and the bottom plate 3 are used to make holes for the openings 5, and then the resulting parts are heat welded. It can also be manufactured by

EXAMPLES The present invention will be explained in more detail below with reference to Examples.

In addition, in the examples and comparative examples, the compression test was performed using pressure! I? i speed force Omm/min (longitudinal compression with 't,
I measured the redundancy of 111 in the form of 琶1: based on the load.

Example: A high-density ethylene polymer (density 0.E150 g/cm') with an HLMFR of 2.0 g/10 minutes was extruded using an extruder (row 90 mm) at a resin temperature of 208°C. A lump of the high-density ethylene polymer was prepared.

The soul obtained in this way is compressed using a compression processing machine under the conditions of a pressure of 100 tons and a mold temperature of 100°C, and then 20°C for 1 hour or 1 minute. A top plate and a base plate with a diameter of 580 mm, a thickness of 4 mm, and a height of 150+ am were manufactured.

Furthermore, the high-density ethylene polymer was processed using an extruder (diameter 1
50 mm), extruded at a resin temperature of 260'C and a tensile speed of 1 m/min, and the diameter was 580 mm.
and the maximum wall thickness is 4, 2mm and the minimum is 3.9+
A pipe of nfI was manufactured. Next, this pipe was cut to a length of 600 mm to produce a side plate.

Like this! 1. Preheat the side plates, top plate, and base plate that have been heated at a temperature of 250°C for a preheating time of 90 seconds, and then press-bond them under a pressure bonding condition of 6 kg/cm'. Therefore, the average wall thickness is 4.0 Omω and the capacity is 22
6 sentences and weight 8.5Kg, (l or 59 (1+no
A drum can with a height of 890 mm was manufactured.

Comparative example) A high-density ethylene polymer (density 0.950 g/cm') with an ILMFR of 2.0 g/10 min was molded using a blow molding machine, the resin temperature was 205°C, the blow pressure was G, and OKg /cm m', mold clamping pressure is 200Kg/c
By blow molding at m' and then cooling for 180 seconds, the volume-h) was 223 and the average wall thickness was 5.32.
A drum can with a diameter of 588 mm, a height of 900 mm, and a weight of IO and 5 kg was manufactured. The wall thickness of this drum had a maximum thickness of 10.5 mm and a minimum thickness of 2.81 mm, with considerable variation.

A compression test was conducted on each of the drums obtained as described below. The results are shown in FIG.

In this figure, the vertical axis shows the load (Kg), and the horizontal axis! +
Tatebroom (mm) or real child or child Al child Takara Watami II 1:
” J-shows the results of the drum cans obtained by heating, and B shows the results of the tram cans obtained by the comparative example.

In addition, these tram cans were filled with 98% water.

After hoisting the top plate with the top plate facing down, tilt the top plate at an angle of about 30 degrees and drop the top plate from a height of 1.8 m so that the bottom plate corner on the parting line is the point of impact. 1. After hanging with the top facing down, tilt it approximately 30 degrees to the vertical axis so that the corner of the top plate of the spout becomes the point of impact.
Drop test from a height of 8m and 90 against vertical axis
Tilt it over and lift it up so that the spout is vertical +11 and use the side plate or the seed i'! ;′! 1 and f, 1.8
Height force of m・drop of ÷21・was performed. The size of the drum 1 and the size 1 were determined by the Examples and Comparative Examples.

There was no damage caused by any of the drop tests, and there was no leakage of the book's contents.

From the results of the above examples and comparative examples, when manufacturing containers (tram < h) using the blow molding method, the wall thickness distribution is poor, and the amount of deformation due to load is large.
The container of the present invention has a uniform wall thickness of 2FT, so it is not a scale that can measure costs due to weight reduction of 9).
It is clear that the deformation due to load (1) is also small.

1. The uninvented hollow container, including its manufacturing process, exhibits the following effects.

(1) Has uniform wall thickness distribution.

(2) Since a synthetic resin with a high molecular weight can be used, the mechanical strength of the hollow container is excellent.

(3) The molds and molding IAs used in manufacturing are relatively inexpensive.

(4) Since a hollow container having a uniform wall thickness distribution can be manufactured, costs can be reduced by reducing weight.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a hollow container of the present invention. Also, the second
The figure is a longitudinal sectional view of the hollow container, and FIG. 3 is a longitudinal sectional view of each part of the hollow container, the longitudinal sectional view of which is shown in FIG. 2, before welding. Furthermore, FIG. 4 is a longitudinal sectional view of an example of the top plate and the bottom plate. Figure 5 is a diagram showing the relationship between the load (vertical axis) and the amount of deformation (horizontal axis is also 11) of the hollow container subjected to tIJ according to the example and the comparative example. l... Container 2... Radish 3... Main plate 4... Side plate 5... ... Mouth part 6 ...... Welding part

Claims (1)

[Claims] The side plate of a synthetic resin hollow container is extruded into a tubular body,
Also, a synthetic resin hollow container obtained by compression molding the top plate and the bottom plate and integrating them.