JPH0669816B2 - Synthetic resin open drum - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an open drum made of synthetic resin having a structure suitable as a container for carrying chemicals, surfactants, juice concentrates, and in some cases, frozen storage. . More specifically, the side plate and the base plate are integrally formed by hollow molding of an olefin polymer, and are provided with flanges protruding from the side plate of the container at intervals below the opening of the container, and the grip portion is provided on the base plate of the container. The base of this gripping portion is provided at least 10 mm inside from the outer periphery, and the width of the inclined compression portion of the gripping portion is at least 15 mm, which relates to an open drum made of synthetic resin, a chemical agent,
It is an object of the present invention to provide an open drum made of synthetic resin having a structure suitable for transporting a surfactant, juice stock solution, or in some cases frozen storage.

Conventional technology Making large containers such as drums into resin is extremely effective in reducing weight, improving durability, and improving rust resistance.
Various synthetic resin drums have already been used in Europe and America. In Japan as well, some open drums (with a lid on the top plate that can be opened and closed) have been partially commercialized for transporting and storing chemicals, surfactants, juice concentrates, etc. (in some cases, frozen storage). It is used.

However, commercialized open drums made of synthetic resin are required to have a high impact strength, so that it is unavoidable to use a material having a poor flow (fluidity) (a large molecular weight). For this reason, it is molded by the hollow molding method, and efforts are made to make the radius of the corner as large as possible (the radius is at least 20 mm or more) in order to prevent the corner from being thin, and the overall shape is as smooth as possible. Because of such a shape, there is no grip for catching a hand on the main plate, and even if a recess is provided as the grip, the shape is too smooth and insufficient. from these things,
It is desired that the main plate be provided with a grip for facilitating the taking out of the contents and the handling of the container, and that the grip has the effect of improving the stability when the containers are directly stacked and preventing slipping.

Problems to be Solved by the Invention From the above, the present invention does not have these drawbacks (problems), that is, the grip portion is provided on the main plate of the synthetic resin open drum, and the grip portion is a container (open drum). ) Is to obtain an open drum made of synthetic resin, which has an improved stability when directly stacked and a non-slip effect.

Means and Actions for Solving Problems According to the present invention, these problems are that the side plate and the base plate are integrally formed by hollow molding of an olefin-based polymer, and are spaced below the opening of the container. The container is provided with a flange protruding from the side plate, and the bottom plate of the container is provided with a grip portion, the base of the grip portion is provided at least 10 mm inside from the outer periphery, and the width of the inclined compression portion of the grip portion is at least 10 mm. It can be solved by a synthetic resin open drum, which has 15mm. Hereinafter, the present invention will be specifically described.

The olefin polymer used in the present invention is an ethylene homopolymer having a density of 0.935 g / cm ³ or more, and ethylene and α-olefins containing ethylene as a main component (usually having 3 to 12 carbon atoms, copolymerization A copolymer with a proportion of at most 15% by weight) is suitable. The molecular weights of these ethylene homopolymers and copolymers of ethylene and α-olefin vary depending on the size (capacity) of the container, but the temperature is 190 ° C according to the melt flow index (JIS K-6760).
And the load is measured under the condition of 21.6 kg, hereinafter referred to as "HLMFR"), for example, in the case of a container with a capacity of 200,
Generally, it is 5.0 g / 10 minutes or less, preferably 4.0 g / 10 minutes or less, and particularly preferably 3.5 g / 10 minutes or less. In the case of a container with a capacity of 20, the HLMFR is usually 5-50 /
10 minutes, preferably 10-50g / 10 minutes, especially
Those of 10 to 40 g / 10 minutes are suitable.

Hollow molding (blow molding) of the above-mentioned olefin polymers generally carried out in the field of olefin polymers
According to the method, the present invention can be achieved by manufacturing a drum provided with a side plate and a top plate and a ground plate having a gripping portion described later. At this time, the molding temperature is usually 180 to 250 ° C, and particularly preferably 190 to 230 ° C.

In manufacturing the synthetic resin drum of the present invention, one of the features is to provide a grip portion on the base plate in order to reduce the difference in blow ratio, and the root of this grip portion is provided 10 mm or more inside from the outer circumference of the drum. By doing so, it is possible to reduce the extension distance of the parison, prevent notches and build-up generated on the inner surface of the grip portion integrally formed at the time of blow molding, and improve the strength capable of withstanding the impact when dropped.

Further, in order to integrally form the grip portion, it is necessary to weld a parison that has been pre-blown once at the time of hollow molding by operating a part of the base plate mold. It is necessary to incline the pre-blown parison by 15 mm or more by inclining it in the outer peripheral direction in order to improve the welding strength of the welded grip and to prevent notches and buildup that occur on the inner surface of the grip. is there.

As described above, according to the present invention, the grip portion can be formed on the main plate, the contents can be easily taken out and the container can be easily handled, and the diameter of the grip portion formed on the main plate surface can be changed to the top plate (cover). By making the diameter slightly smaller than the diameter of the recessed portion in (1), stacking at the time of direct stacking, which has been unstable in conventional drums, becomes easy and stability is improved. Further, it is needless to say that the gripping portion itself exerts the anti-slip effect, and the anti-slip can be prevented by providing an anti-slip device made of water, ice or the like as in a frozen warehouse.

Hereinafter, a detailed example of a synthetic resin drum according to the present invention will be described in detail with reference to FIGS. 1 to 5 in comparison with a comparative example.

FIG. 1 is a vertical sectional view of a synthetic resin open drum of the present invention. The structure of the upper part of the drum is the same as that of the conventional drum described later, but the grip portion 4 provided on the main plate is formed by the compression process at the time of hollow molding of the main body. FIG. 2 is a vertical sectional view of a conventional synthetic resin open drum. In these figures, 3 is a drum body. Reference numeral 2 is a flange protruding from the container side plate at a distance below the opening (usually 20 to 50 mm in the case of the present invention), and 1 is a lid (top plate),
1a is a concave portion of the lid. In addition, in FIG. 2, since the grip portion 4 provided on the main plate has a smooth shape, the grip is insufficient. FIG. 3 is an enlarged vertical sectional view of a portion (shown as A in FIG. 1) near the grip portion of the synthetic resin open drum of the present invention. In this figure,
Reference numeral 4 is a grip portion, and 8 is a main plate. Further, 5 is an outer circumference (side plate). Further, 6 is a padding on the inner surface of the grip portion, and 7 is a notch on the inner surface of the grip portion. Further, x is the dimension from the outer circumference to the base of the grip portion, and y is the width of the inclined compression portion. In the present invention, by setting x to 10 mm or more and y to 15 mm or more, the buildup 6 and notch on the inner surface of the grip portion become gentle, and the impact is not concentrated, so that the impact such as when dropped A synthetic resin open drum with improved strength against FIG. 4 is a partially enlarged vertical sectional view when stacking. In this figure, the gripping portion 4 provided on the base plate is fitted into the concave portion 1a of the lid to improve the stability during stacking. In addition, in these drawings, the band with the lid fastening and the packing are omitted.

Examples and Comparative Examples Hereinafter, the present invention will be described in more detail with reference to Examples.

In the examples and comparative examples, the impact resistance of each of the obtained olefin-based polymer drums was dropped so that the drum cans were filled with water at 98% of the capacity, and the main plate was hung vertically so that the bottoms of the drums were suspended. , A drop test from a height of 1.8 m so that the corner of the main plate on the parting line will be the impact point [hereinafter referred to as "test (I)"], and after hanging with the main plate down, with respect to the vertical axis Tilted about 30 degrees and 1.8m so that the ground plane corner on the parting line becomes the impact point
A drop test [hereinafter referred to as "test (II)"] was performed from the height.

Example High density ethylene polymer having HLMFR of 5.1 g / 10 min (density
0.955g / cm ³ ) using a blow molding machine and the resin temperature is 203
℃, blow pressure 6.0 kg / cm ² , mold clamping pressure 200 kg / cm ² (15
The volume is 224, the average wall thickness is 4.31mm (maximum wall thickness 9.8mm, minimum wall thickness 3.0mm), body diameter is 582mm, and height is 931mm. And an open drum can as shown in Fig. 1 was produced having an x of 15 mm and a y of 20 mm in Fig. 3 and a weight of 8.1 kg.

Comparative Example High density ethylene polymer with HLMFR of 5.2g / 10min (density
0.955g / cm ³ ) using a blow molding machine and the resin temperature is 205
℃, blow pressure 6.0 kg / cm ² , mold clamping pressure 200 kg / cm ² (15
The volume is 223, the average wall thickness is 4.22mm (maximum wall thickness is 10.7mm, minimum wall thickness is 3.2mm), the body diameter is 587mm, and the height is 968mm. An open drum, shown in FIG. 2, weighing 7.6 kg was produced.

When an impact resistance test was conducted by dropping 10 of each of the obtained drum cans, the open drums obtained in the examples were tested for water (I) and test (II) due to damage and cracking. No leak was observed. On the other hand, in the test (I) of the open drum cans obtained in Comparative Example, no water leakage due to breakage and cracking was observed, but in Test (II), cracking occurred in 3 out of 10 drums. Water leakage was observed.

Effect of the Invention The open drum made of the synthetic resin (olefin polymer) of the present invention includes the following manufacturing processes (effects).
Exert.

(1) It is easy to take out the contents and handle the container.

(2) If the grip provided on the main plate serves as a non-slip material and it is extremely slippery on water, ice, etc., it is easy to install a non-slip material such as rubber.

(3) Stacking is easy when stacking and is stable.

(4) It can be manufactured at low cost and can be manufactured more easily.

(5) It is lightweight.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a synthetic resin open drum of the present invention, and FIG. 2 is a vertical sectional view of a conventional synthetic resin open drum. Further, FIG. 3 is an enlarged vertical sectional view of a portion A of the synthetic resin open drum of the present invention whose longitudinal sectional view is shown in FIG. Further, FIG. 4 is a partially enlarged vertical sectional view when stacking the synthetic resin open drum of the present invention. 1 ... Lid (top plate), 1a ... Lid recess 2 ... Flange, 3 ... Drum body 4 ... Grip provided on the ground plate 5 ... Outer periphery 6 ... Padding on inner surface of grip 7 ...... Notch on the inner surface of the grip 8 …… Main plate

Continuation of the front page (56) References JP-A-59-163153 (JP, A) JP 52-8499 (JP, Y2) JP 56-48645 (JP, Y2)

Claims (1)

[Claims] 1. A side plate and a base plate are integrally formed by hollow molding of an olefin polymer, and are provided with flanges protruding from the side plate of the container at intervals below the opening of the container,
An open drum made of synthetic resin, in which the bottom plate of the container is provided with a grip portion, the base of the grip portion is provided at least 10 mm inside from the outer circumference, and the width of the inclined compression portion of the grip portion is at least 15 mm.