JP2560573B2 - In-mold label - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a label for a plastic container, which is used for hollow molding or biaxially stretched hollow molding and is integrated with the surface of the container simultaneously with blow molding.

[0002]

2. Description of the Related Art Conventionally, a labeled container in which a label on which characters, patterns, etc. are printed is attached to the surface of a molded plastic container has been generally used in the market. Since the label is attached to the container thus formed afterwards, the number of work steps is increased, and the label is in a state of protruding on the surface of the container, the appearance is not good, and the label is peeled off from the periphery of the label. I was afraid.

As an alternative to this, a container integrally provided with a label at the same time when the container is molded has been used. The container integrated with this molding had a structure in which the label surface became the same height as the other surface of the container, and the label became a part of the container.

A label used in a container in which a label is integrated simultaneously with this molding (hereinafter referred to as an in-mold label)
Various materials are used depending on the material of the container or the molding method, but in general, the adhesive varnish for the container is a film such as a film of ethylene vinyl alcohol or a paper coated with a heat seal varnish, synthetic paper or A plastic film as a base material is used.

[0005]

The in-mold label as described above has a high adhesive strength (500 g / 15 mm) in consideration of recycling of the plastic container, and it takes a lot of time to peel the label from the container. It was impossible to crush and reuse the label), and because the surface of the label was flush with the other surface of the container and the label became part of the container, the end of the label There is a problem that it is not possible to grasp the label because it is not possible to stand on the nails, etc. Furthermore, when the base material is paper, there is a problem that a part of the label remains on the container due to peeling of the paper. there were.

Further, when the label base material is a plastic film, as a problem of the appearance of the container after molding, whether the plastic film of the label base material has extremely poor dimensional stability with respect to the material resin of the container, or it is thick. When the above plastic film is used, there is a problem that the label may be wrinkled or the container may be deformed after the container is molded.

[0007]

In an in-mold label used when integrated with a container simultaneously with blow molding, a heat-sealing varnish having a constant width is provided from the outer edge only on the outer periphery of a base material made of a plastic film. The in-mold label is characterized in that a part of the outer peripheral heat seal varnish is absent.

[0008]

When a labeled container is formed by using the above in-mold label, since the heat seal varnish is provided on the outer periphery of the label, the label is completely adhered to the container.
It has excellent physical properties as a product, allows the edges of the label to be easily grasped, enables peeling with a weak force, and is suitable for container recycling.

[0009]

EXAMPLES The present invention will be described in detail below with reference to examples. 1 and 2 are explanatory views showing an embodiment of the in-mold label of the present invention, in which characters are formed on the surface of a substrate 1 made of a plastic film. A print 2 of patterns etc. is provided,
If necessary, a 0P varnish 3 or the like is provided thereon.

On the other hand, on the back surface of the base material 1, as shown in FIG. 1, a heat seal varnish 4 is provided only on the outer periphery with a constant width from the outer edge, and a part of the outer periphery of the outer heat seal varnish is provided. Part 5 is missing.

As the heat seal varnish 4, it is preferable to provide an ethylene vinyl alcohol-based varnish with a width of 5 to 15 mm from the outer edge and a coating amount of 10 to 5.0 g / m ² .

Here, as the base material 1, stretched or unstretched films of high-density polyethylene, polyester, polypropylene, or other materials such as polyester-based or polypropylene-based synthetic paper can be used. Further, in the above description, the label shape is rectangular, but it may be oval or any other shape, and the portion lacking the heat seal is set at the corner of the base material in the present embodiment, but it may be at another place. However, in consideration of peeling the label, it is preferable to provide the corner of the base material or the curved surface of the label at a place having a small curvature.

Here, as a container molding method using this label, it can be used for general plastic blow hollow molding or biaxial stretch blow molding, and the molding method is not limited, and the container is As the material, various resins such as low density polyethylene, high density polyethylene, ethylene propylene copolymer and polyester can be used.

Next, a concrete example is shown. The base material (1)
As the material, a rectangular one having a length of 100 mm, a width of 80 mm and a rounded corner, and a high-density polyethylene film having a thickness of 80 μ is used.
As an ethylene vinyl alcohol-based product manufactured by Toyo Morton Co., Ltd., AD. 1790} with a width of 10 mm from the outer edge and a coating amount of 2.0 g / m ² , one of the corners of the rectangular label is a missing part 5 without the heat-sealing varnish.
Was formed.

Using this label, a high-density polypropylene resin or a polyester resin was used as a plastic resin for a container and a bottle was integrally formed with the label at the same time as the molding. Even under the conditions of 20 ° C and 50 ° C 90% Rh, there is no wrinkle, which is a label adhesion state, and there is no deformation of the bottle.
A sufficiently good result was also obtained in the thermal shock test under the conditions of r and 10 cycles.

Further, in this molded container, the label peel strength test was carried out by changing the heat seal width and peeling the test from the portion lacking the heat seal varnish in an oblique direction. As a result, the heat seal width was 5.0, 10. 0, 15.0,
20.0 mm and 0.
It exhibited peel strengths of 6, 1.4, 1.8, 2.3, and 6.0 kgf.

Further, as a base material, 100 μl polyester synthetic paper was used, and a bottle molded by using high density polypropylene resin and polyester resin was tested. As a result, the same good result as above was obtained. .

[0018]

The present invention has the above-mentioned constitution, and the in-mold label of the present invention has no deformation at the time of molding even when a thick plastic film is used as a base material, and when considering recycling of the container. In addition to the fact that the label can be peeled off with a weak force from the lack of the heat-sealing varnish, the label is completely adhered by the heat-sealing varnish, and thus the product of the bottle molded by using the present invention. It is possible to have sufficient physical strength. Even if a plastic film, which has better dimensional stability than the container resin, is used as the base material of the label, it has an air layer and an escape path for the air between the label and the container. There is an effect that there is no.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of the in-mold label of the present invention.

FIG. 2 is a cross-sectional explanatory view showing an embodiment of the in-mold label of the present invention.

[Explanation of symbols]

 1 ... Substrate 2 ... Printing 3 ... Overcoat varnish 4 ... Heat seal varnish 5 ... Heat seal varnish

Claims (1)

(57) [Claims] 1. An in-mold label used for integration with a container simultaneously with blow molding, wherein a heat-sealing varnish is provided with a constant width from the outer edge only on the outer circumference of a base material made of a plastic film, and the outer-circumferential heat-sealing varnish is formed. An in-mold label characterized by a partial lack.