JPS5821690Y2 - Polyolefin resin plate-shaped molded product with destroyed air bubbles - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a polyolefin resin plate-like molded article in which most of the giant cells of a foamed polyolefin resin plate-like article having giant cells have been destroyed.

In general, research has been carried out on polyolefin resin foam sheets to obtain sheets with good flexibility, whiteness, etc. by making the cells finer.

The present inventor discovered that by using a special composition, a thick foamed polyolefin resin plate having huge cells can be obtained by extrusion molding.

It has been found that this foamed polyolefin resin plate having giant cells is strong and has good shock absorption properties due to the air contained therein, and can be used as various cushioning materials, packaging materials, etc.

However, it has been further discovered that by destroying most of the giant cells in this foamed polyolefin resin plate, a molded article with special properties can be obtained, which can be used for various purposes.

The present invention was made based on this knowledge, and
It has a foaming ratio of 20 to 80 times and an IQm of 2 mm or more.
3 to 50 cells in which giant cells consisting of nearly spherical closed cells with a cell diameter of less than m account for 60% or more of the total volume of the foam.
A foamed polyolefin resin plate having a thickness of 1.0 mm, in which linear cuts are made from both the upper and lower surfaces of the foamed polyolefin resin plate to destroy most of the giant cells. The gist is a plate-shaped molded body.

Examples of the polyolefin resin used in the present invention include polyethylene, polypropylene, polybutene, and copolymers of these resins.

Among them, low-density polyethylene is suitable for forming a foam plate-like body having a high expansion ratio.

The polyolefin resin foam plate used in the present invention is a plate with a thickness of 3 to 50 mm, and the foam plate has giant cells consisting of nearly spherical closed cells with a cell diameter of 2 mm or more and 10 mm or less. It occupies more than 60% of the total volume.

Each bubble is approximately spherical, but the bubble membranes in which the bubbles are in contact with each other form a polyhedron.

Although fine bubbles are formed in the corners surrounded by giant bubbles, giant bubbles account for 60% of the total volume.
occupies more than

It is preferable that the giant bubbles have a uniform diameter.

In the present invention, most of the giant cells in the foamed polyolefin resin plate having giant cells are destroyed.

In order to destroy air bubbles, linear cuts are made from both the upper and lower sides of the plate.

The cut may be a straight line or an interrupted line (dashed line).

In order to prevent the foamed polyolefin resin plate from being cut, the cuts are preferably made at a depth of ± or less than the thickness of the plate.

Therefore, it is preferable to provide the cuts at positions shifted from both the upper and lower surfaces of the plate-shaped body.

The intervals between the cuts are appropriately selected depending on the size of the giant bubbles, and the cuts are provided at intervals such that most of the giant bubbles are destroyed.

For example, if the average bubble diameter of giant bubbles is 5 mm, 5 m
Most of the giant bubbles are destroyed by making cuts at intervals of m.

The cuts may be made, for example, by abutting a rotating blade, or the cuts can be easily made by passing the foamed polyolefin resin plate through the gap while rotating a pair of drums having shearing blades. can be provided.

To explain the drawings, Fig. 1 is an explanatory diagram schematically showing in a perspective view a state in which cuts are made in a foamed polyolefin resin plate, and Fig. 2 is an end view taken along the line A-A in Fig. 1. be.

In the drawings, reference numeral 1 indicates a polyolefin-based resin plate-shaped molded product of the present invention in which the cells have been destroyed. For example, the large spherical cells obtained by extrusion foaming polyethylene account for 60% or more of the total volume of the foam. This is a plate-shaped body that occupies a large area, with linear cuts cut from both the top and bottom sides.

2 is a giant bubble, and 3 is a fine bubble surrounded by the giant bubble 2.

4 is a cut, and 4' in FIG. 1 is a cutting line for making the cut 4. Although it does not appear linearly in the polyolefin resin plate-shaped molded product 1, it is shown in a model for ease of understanding. This is the line shown in .

The cuts 4 are formed at equal intervals on the upper and lower surfaces of the polyolefin resin plate-shaped molded product 1, and the cutting lines 4' on the upper surface and the cutting lines 4' on the lower surface are provided at different positions. There is.

The cut 4 formed by the cutting line 4' causes most of the giant bubble 2 to be destroyed by shearing its bubble membrane.

The bubble-destructed polyolefin resin plate-shaped molded article 1 of the present invention has the above-described structure, and most of the giant bubbles 2 are destroyed and there are very few sealed air layers.
It has very good flexibility, like a polyurethane foam with open cells, and the sheared cell membrane is elastic and has the property of returning to its original state.

Moreover, the surface area of the molded body is significantly expanded by destroying the giant bubbles 2, and the molded body has a strong ability to adsorb water and various other substances.

As mentioned above, the polyolefin resin plate-shaped molded article 1 of the present invention in which the bubbles are destroyed has unique properties.
In addition to being used as cleaning tools such as towels, rags, and bundles, it can also be used as an oil adsorbent or a liquid or gas filtration material.

Additionally, it has good elasticity and cushioning properties, making it useful as a packaging material for glass and ceramic products.

[Brief explanation of the drawing]

The drawings illustrate a polyolefin resin plate-shaped molded article in which bubbles are destroyed according to the present invention, and FIG. 1 is a perspective view schematically illustrating the same. FIG. 2 is an end view taken along the line A--A in FIG. 1. The main symbols in the drawings are as follows. 1...Polyolefin resin plate-shaped molded body, 2.
...Giant bubbles, 3...Micro bubbles, 4...
...cut, 4'...cutting line.

Claims (3)

[Scope of utility model registration request] (1) Giant cells consisting of nearly spherical closed cells with an expansion ratio of 20 to 80 times and a cell diameter of 2 mm or more and 1Q mm or less occupy 60% or more of the total volume of the foam3
A foamed polyolefin resin plate having a thickness of ~5 Qmm, in which linear cuts are made from both the upper and lower surfaces to destroy most of the giant cells. Resin plate-shaped molded body. (2) Scope of utility model registration claims characterized in that the cuts are made in straight or interrupted lines from both the upper and lower surfaces at intervals of 2 to 10 mm at a depth of approximately ÷ the thickness of the plate-like body or less. 2. The polyolefin resin plate-shaped molded article in which bubbles are destroyed as described in item 1. (3) The polyolefin resin plate-shaped molded article in which air bubbles have been destroyed, as set forth in claim 1, wherein the polyolefin resin is polyethylene or polypropylene.