JP4298082B2 - Translucent foamed polyolefin resin sheet - Google Patents

Description

【００１５】
本明細書に具体的に明示する本発明の実施形態は概ね上記のとおりであるが、本発明は前述の実施形態に限定されるものでは決してなく、「特許請求の範囲」の記載内において種々の変更が可能であり、例えば、ポリオレフィン系樹脂を発泡押出成形する際に上記配合に加えて適宜の淡色顔料を添加することによって演色効果を増進することができ、このような変更が本発明の技術的範囲に属することは言うまでもない。
【００１６】
ちなみに、上記実施形態１の試料に更に各種の顔料を添加して比較してみたところ、次のような結果が得られた。

ちなみに、Yellowの顔料を用いたために気泡調整剤効果が生じて気泡が微細になり過ぎて、所期の透光性能が得られなかった。
【００１７】
【発明の効果】
以上、実施形態を例示して説明したとおり、本発明にあっては発泡ポリオレフィン系樹脂シートにおける気泡を泡径１〜10mm（長径部位）のサイズ範囲に調整して混在分布させたので、製品自体は透光性に富んで外観的に美しく、しかも、透視性能が従来の発泡樹脂シートに比較して格段に良好なので、包装材料として用いた場合には包装した物品を認識させることができるのに加え、気泡を透して中の物品を美麗に演出することができる。
【００１８】
また、本発明の発泡ポリオレフィン系樹脂シートにあっては、気泡の膜厚を薄くすることによって、気泡膜を通過する光や、気泡膜で反射される光が干渉して美麗な鋭敏色を呈するから、包装材料として用いたり、壁シート材料として用いる場合には独特の装飾性を発揮し得るのであり、包装デザインの表現手段としても、インテリア・デザインの表現手段としても秀れた効果を発揮できる。
【００１９】
このように本発明によれば、乱反射によって透光性・透視性が期待できなかった従来の発泡樹脂シートと異なって透光性・透視性に富み、更には光干渉による演色効果を発揮させることも可能であるので、包装材料や建築材料としての用途面には大きな実用的効果を発揮することができる。[0001]
BACKGROUND OF THE INVENTION
The present invention is an improvement of the foamed resin sheet, more specifically, it has translucency and has a beautiful appearance, as well as the translucent foam capable of producing beautifully the object that can be seen through it. The present invention relates to a polyolefin-based resin sheet, and is suitable for use as a packaging material or as a heat insulating sheet laid on a wall sheet or visible portion.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a foamed sheet obtained by foaming a polyolefin resin such as polyethylene resin into a sheet shape has been used in a wide range of fields as a packaging material, as a heat insulation packaging material, or as a heat insulating material for buildings.
[0003]
By the way, a conventional foamed polyolefin resin sheet is extrusion-molded by kneading a low-boiling solvent, gas, or decomposable foaming agent into a polyolefin-based resin (for example, polyethylene) or mixing it under pressure. Efforts were made only to disperse the finest possible bubbles uniformly in the resin. Therefore, even if a highly transparent polyolefin-based resin is used as the material, the foam sheet obtained has an opaque white appearance because the bubbles dispersed in the resin diffusely reflect light. It was possible to obtain a transparent product only by kneading and coloring to an appropriate color.
[0004]
However, when foam sheets are used as packaging materials, it is not possible to see what the wrapped article is, and even if the type of article is known from its shape and weight, it does not go out of speculation and can be used as a packaging design. There is no change. However, not a foamed sheet, but a simple transparent resin sheet, neither buffering property nor heat retention is obtained, and it is disqualified as a packaging material.
[0005]
Also, when foam sheets are used as building wall sheets or heat insulating materials, opaque single colors cannot meet the demands of interior design.
[0006]
[Problems to be solved by the invention]
The present invention was made in view of the above-mentioned design difficulties in the conventional foamed sheet produced using a polyolefin-based resin as a material. It is rich in translucency and beautiful in appearance. Moreover, it is an object of the present invention to provide a translucent foamed polyolefin-based resin sheet with excellent decorativeness capable of beautifully producing an object that can be seen through.
[0007]
In addition, another technical problem of the present invention is to provide a translucent foamed polyolefin resin sheet in which a bubble film of bubbles contained in the sheet causes a beautiful optical interference phenomenon and exhibits a highly sensitive and sensitive color. There is.
[0008]
[Means adopted to solve the problem]
That is, the present invention provides a bubble diameter adjusting means for coexisting and distributing bubbles in a size range of 1 to 10 mm in the polyolefin resin on the premise of a sheet molded body in which bubbles are dispersed in the polyolefin resin. It is characterized in that the above-mentioned technical problem is solved by adopting it.
[0009]
The polyolefin resin referred to in the present invention includes polybutylene and polyisoprene in addition to polyethylene and polypropylene, and a flexible polyethylene resin is particularly preferable.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, specific contents of the present invention will be described with reference to embodiments.
[0011]
Embodiment 1
For molten low density polyethylene, butane was injected at 20 kg / h and the temperature in the vicinity of the die of the extruder was adjusted to about 100 ° C. and extruded to produce a foamed polyethylene sheet having a thickness of 1.0 mm (hereinafter referred to as foaming). A polyethylene sheet is referred to as Sample 1). Sample 1 obtained in this way has a bubble diameter size of 1.5 to 3.5 mm (longer diameter portion) and is distributed substantially uniformly. The foamed polyethylene sheet of Sample 1 can be seen from the front and through the back. However, the bubbles interfered with light in the bubble film and exhibited a brilliant and sharp color.
[0012]
On the other hand, an air conditioner (talc) is added to molten low-density polyethylene as needed, and butane is injected at 20 kg / h and 1,1,1,2-tetrafluoroethane is injected at 2 kg / h. The temperature in the vicinity was extruded at 100 ° C. to obtain a foamed polyethylene sheet (hereinafter referred to as Comparative product 1) having a thickness of 1.2 mm. The foamed polyethylene sheet thus obtained had an average cell diameter of about 0.7 mm and appeared white in appearance.
[0013]
Thus, when comparing the “haze vale” between the sample 1 and the comparative product 1, the haze value of the sample 1 was 19.0%, and the haze value of the comparative product 1 was 79.1%. The higher the haze value, the lower the transparency, and the comparative product 1 was pure white and could hardly be seen through, but the sample 1 was an article about 30 cm high and about 10 cm wide 5 meters ahead. There was fluoroscopy performance that could distinguish what it was.
[0014]
Next, when the mechanical properties of Sample 1 and Comparative Product 1 were measured in accordance with “JIS K 6767”, the following results were obtained.

[0015]
Although the embodiments of the present invention specifically specified in the present specification are generally as described above, the present invention is in no way limited to the above-described embodiments, and various modifications can be made within the scope of the claims. For example, when a polyolefin resin is subjected to foam extrusion molding, a color rendering effect can be enhanced by adding an appropriate light color pigment in addition to the above-mentioned compounding. Needless to say, it belongs to the technical scope.
[0016]
By the way, when various pigments were further added to the sample of Embodiment 1 and compared, the following results were obtained.

Incidentally, since the Yellow pigment was used, a bubble adjusting effect was produced and the bubbles became too fine, and the desired light transmission performance could not be obtained.
[0017]
【The invention's effect】
As described above, as an example of the embodiment, in the present invention, the bubbles in the foamed polyolefin-based resin sheet are mixed and distributed in the size range of the bubble diameter of 1 to 10 mm (long diameter part), so that the product itself Is highly translucent and beautiful in appearance, and its fluoroscopic performance is much better than conventional foamed resin sheets, so that it can recognize the packaged article when used as a packaging material. In addition, it is possible to produce beautiful articles through the bubbles.
[0018]
Further, in the foamed polyolefin resin sheet of the present invention, by reducing the film thickness of the bubbles, the light passing through the bubble film and the light reflected by the bubble film interfere with each other to exhibit a beautiful sharp color. Therefore, when used as a packaging material or as a wall sheet material, it can exhibit a unique decorative property, and can exhibit excellent effects as a packaging design expression means and an interior design expression means. .
[0019]
As described above, according to the present invention, unlike conventional foamed resin sheets that could not be expected to have translucency and transparency due to irregular reflection, it is rich in translucency and transparency, and further exhibits a color rendering effect due to light interference. Therefore, a large practical effect can be exerted in the use as a packaging material or a building material.

Claims (4)

A translucent foamed polyolefin-based resin sheet, which is a sheet molded body in which bubbles are dispersed in a polyolefin resin, wherein bubbles in a size range of a bubble diameter of 1 to 10 mm in a major portion are mixed and distributed. 2. The translucent foamed polyolefin resin sheet according to claim 1, wherein the translucent foamed polyolefin-based resin sheet exhibits a sensitive color by interference of light passing through a bubble film forming bubbles or light reflected by the bubble film. The translucent foamed polyolefin resin sheet according to claim 1, wherein a low-density polyethylene resin is used as the polyolefin resin. The translucent foamed polyolefin resin sheet according to any one of claims 1 to 3, which exhibits a light transmittance of a haze value of 40% or less.