JPH0223398Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multilayer container with metallic luster.

Recently, aluminum containers have been increasingly used to improve the shelf life of food products, give the container a sense of luxury, and increase the added value of the product. There are many cases where food gets dented and becomes defective due to impact, and there is also a risk of injury to fingers when opening the package.Furthermore, acidic foods have the disadvantage of being corroded. On the other hand, plastic containers are less susceptible to deformation due to dents, and even if dents occur, they have the ability to quickly restore their original shape. If used as a container material, it will not be attacked by acidic foods. However, the sense of luxury as a container is not as high as aluminum containers. For this reason, the inventor of the present invention conducted various studies to find out whether it was possible to create a container that has the so-called metallic luster, giving it the luxury feel of an aluminum container while taking advantage of the excellent functions of a plastic container. Got the container.

One way to give plastic a metallic luster is to mix aluminum powder, but if you mix aluminum powder directly into plastic, there is a risk of a dust explosion, so paste-like aluminum powder is used. In this case, there was a problem as a food container because the odor of the solvent contained in the paste product remained in the container.

For this reason, the present inventor investigated whether it was possible to make a plastic multilayer container with a metallic luster without using aluminum powder and without odor, and found that mica is an effective material other than aluminum powder to impart a metallic luster to plastic. However, since mica does not have sufficient light-shielding properties, metallic luster cannot be obtained unless it is added in large quantities.On the other hand, adding mica in large quantities can cause problems such as a decrease in physical properties, a decrease in moldability, and a decrease in surface gloss. In order to cover this problem, pigments with strong light-shielding power such as carbon and titanium were used together, and the amount of mica added was not so large. The metallic luster was canceled out by the blended carbon, titanium, etc., making it impossible to obtain a satisfactory metallic tone.

The multi-layer container of the present invention was obtained through various studies to eliminate these drawbacks and give a good metallic luster.The multi-layer container of the present invention is characterized by a layer with metallic luster and a layer to make use of the metallic luster of this layer. A light-shielding layer is provided on the inside, and their complementary effects give the container a metallic luster, thereby providing a metallic container.

That is, in the present invention, the outermost layer 2 is a transparent resin layer, an adhesive layer 5 containing 10% by weight or less of mica, an intermediate layer 4 made of a resin having gas barrier properties, an adhesive layer 6 containing 10% by weight or less of mica, and an oxidized layer. Innermost layer 3 made of resin containing titanium and having a light transmittance of 30% or less
This is a multilayer container 1 characterized in that it is formed from a multilayer sheet configured in the following order.

The multilayer container of the present invention separates the layer containing mica and the layer with light shielding properties, the outermost layer is transparent resin such as polypropylene, the layer containing 10% by weight or less of mica is used as an adhesive layer, and the layer containing titanium oxide prevents light rays. Transmittance 30%
The following light-shielding layer was used as the innermost layer, and the resulting container had a good metallic luster, giving it a luxurious feel. If too much mica is added, it will be difficult to blend with plastic,
Also, when the light transmittance is 40 to 50%, which is good, the light shielding property becomes poor and it becomes difficult to produce metallic luster. Pigments such as carbon and titanium are usually mixed into the plastic to provide a layer with light blocking properties.

Plastic materials used for the innermost layer 3 include polystyrene (PS), polycarbonate (PC), saponified ethylene/vinyl acetate copolymer (saponified EVA), PP, PE, and ethylene/vinyl acetate copolymer depending on the application. Used materials include EVA, ionomer, polyvinyl chloride (PVC), polyester (PET), nylon (Ny), and polyvinyl chloride resin (PVDC).

Furthermore, by using a resin with excellent gas barrier properties such as saponified EVA or PVDC for the intermediate layer 4, a container with even better storage stability and a metallic feel can be obtained.

Since the outermost layer 2 is a transparent layer made of PVC, PET, PC, PP, etc., the surface gloss is improved without adversely affecting the metallic luster.
In these cases, in addition to improved heat resistance, the mica does not peel off, resulting in a more distinctive container.

The adhesive layers 5 and 6 may be of any material as long as they bond the intermediate layer 4 and the outermost layer 2, and the intermediate layer 4 and the innermost layer 3, but are preferably olefin resins modified with maleic anhydride or the like. The adhesive layer contains mica and also has a metallic luster, so there is no need to provide a resin layer containing mica, and since it is provided in the middle layer, it has a deeper metallic feel. is obtained.

The container of the present invention does not use any solvent during the manufacturing process, so there is no problem with odor, and it can be used for filling food without any problem.

The multilayer container of the present invention is made by vacuum or pressure forming a multilayer sheet made by methods such as coextrusion, dry lamination, extrusion lamination, etc., and a layer with a metallic luster blended with mica to make use of the metallic luster of this layer. A multilayer container having at least a layer having a light shielding property and a layer having a gas barrier property is obtained.

(Example) Outermost layer: 0.1 mm transparent PP Adhesive layer: 0.1 mm PP resin containing 2% mica and 0.1% carbon Middle layer: 0.04mm saponified EVA Adhesive layer: 2% mica and 0.05% carbon PP resin containing 0.1 mm by weight% Innermost layer: 0.56 mm containing 3% by weight titanium oxide
When a multilayer sheet made of PP was molded into a cup container, a container with a pleasant metallic feel was obtained. This container sealed with a lid made of aluminum (12μ)/CPP (50μ) can be sterilized by boiling or retort, which greatly extends the shelf life of the container, making it a container that can replace metal cans.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the multilayer container of the present invention.

Claims (1)

[Scope of utility model registration request] The outermost layer 2 is a transparent resin layer, an adhesive layer 5 containing 10% by weight or less of mica, an intermediate layer 4 made of a resin having gas barrier properties, an adhesive layer 6 containing 10% by weight or less of mica, and a light beam containing titanium oxide. Transmittance
A multilayer container characterized in that it is formed from a multilayer sheet composed of an innermost layer (3) made of 30% or less resin.