JPH072373B2 - Labeled container manufacturing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a labeled container in which a label is embossed, and the label is attached to the body of the container simultaneously with blow molding. At the same time, the present invention relates to a method for manufacturing a labeled container in which the shrinkage of the bottle after molding is used to perform embossing on the label surface in a grain shape.

<Prior Art> Recently, a polyester container having excellent transparency and gloss has been used in place of glass fogging. On the outside of this container,
It has been common to provide a printing layer for displaying contents, displaying products, and providing beauty.

Thus, in order to provide the label after molding, it has to be carried out in a separate step, and a pressure sensitive adhesive or a water-based adhesive is used as the adhesive of the label. A label using a pressure-sensitive adhesive has to be provided with a release paper on the back side, which is expensive, and the release paper has to be peeled off at the time of use, which is inefficient. It was dead.

On the other hand, when the water-based adhesive was used, the adhesive had to be applied by a labeler and adhered to the container, which was similarly inefficient.

As a method of improving this, there is a method of inserting a label into a molding die in advance and applying a label to the outer layer of the container body at the same time as molding (hereinafter referred to as an in-mold label system). Of these, the latter has a number of advantages such as process rationalization, appearance aesthetics, and material cost reduction, and the number of practical examples tends to increase in the future.

As a molding method using the in-mold label system, a parison is continuously extruded from an extruder, cut into a certain length, and blown in a mold with a direct blow method, an injection machine, or an extruder. This is a stretch blow molding method in which a bottomed parison is molded and then molded while being stretched in a blow mold. Of these, the former has many practical examples in containers for detergents, shampoos, foods and the like. In particular, it is effective to emboss the label surface in order to give the container surface a cosmetic appearance.

Conventionally, in order to emboss a label attached to a container, the label in a wound state before being punched on the label is pre-embossed by a molding machine, and then the label is punched on the container. The label has been embossed in the process of sticking to.

<Problem of the Invention> In the above-mentioned conventional technique, when a label has been embossed in advance, and a label is attached to a hollow container by a method of attaching to a label container at the same time as forming, a separate step of embossing the label is required. In addition, when a label is attached to the surface of the container in the subsequent step, the label surface has unevenness compared to a label that is not embossed and has a smooth surface, which makes it difficult to feed the label in the labeling step. In addition, the position accuracy and adhesiveness of the label were not satisfactory.

In addition, if the pre-embossed labels are integrated using the in-mold label system, in addition to the problems of feedability similar to the above, it may be eliminated by the heat pressure during the embossing pattern molding that was previously set, or it may be unclear. There was a fear of becoming.

Therefore, an object of the present invention is to solve the above problems and provide a labeled container having a clear embossed pattern.

<Means for Solving the Problems> In order to solve the above problems, a label having an adhesive layer exhibiting an adhesive effect at one side of the base material on the body of the hollow container at the molding temperature is inserted with the adhesive layer inside. Then, the label is adsorbed at a position corresponding to the label sticking surface of the mold, and then the heat-softened parison is introduced into the mold, and after closing the mold, pressurized air is put into the parison. Blow-in and blow-molding to attach a label to the surface of the container at the same time as molding,
Then, the problem was solved by forming a grain-like embossed pattern on the label surface by utilizing the shrinkage of the container after molding.

As a container material used for molding, those having a relatively large shrinkage ratio after molding are desirable, and examples thereof include polyethylene and vinyl chloride resin. Further, it is desirable that the label base material has such a thickness that a wrinkled embossed pattern can be clearly seen.

<Function> Insert the above label, which is not embossed and has a smooth surface, into the blow mold before the start of blow molding, with the adhesive layer inside, and then pressurize air in the parison. Is blown to form a desired container, and at the same time, the label is attached to the container in a completely adhered state by the heat and pressure at this time. Then, after molding, the container gradually shrinks as the temperature of the container decreases, and if the shrinkage ratio of the container is higher than the shrinkage ratio of the label, the label cannot follow the shrinkage of the container, and the entire label surface is wrinkled. An embossed pattern is formed.

<Example> A label is attached to a high-density polyethylene container having a circular cross section at the same time as hollow molding.

As shown in FIG. 1, the structure of the label A is a synthetic paper (YUPO FPG # 130) with a thickness of 130 μ having thermoformability which is made into an internal pseudo paper.
A base material 1 made of Oji Paper Co., Ltd. is provided with a pattern layer 2 on the front surface, and an adhesive layer 3 made of a heat-sensitive adhesive (Adcoat 33DW1790 manufactured by Toyo Morton) is provided on the back surface.

Next, when the label A is inserted into the portion corresponding to the label surface of the container of the mold 4 shown in FIG. Next, after introducing the parison heat-softened to 180 to 190 ° C. into the mold and closing the mold,
At the same time as molding the container by blowing pressurized air of ~ 10 kgf / cm ^2, the container and the label are attached in a state where the container and the label are completely adhered by the heat and pressure at this time.

Next, after molding, the container temperature decreased to the ambient temperature and the container contracted, resulting in a depth of 0.02 to 0.10 as shown in FIG.
A mm-shaped embossed pattern is formed.

<Effect> By producing a labeled container as in the present invention, the label is attached at the same time as forming the container, and the shrinkage of the container after the forming is used to form a wrinkle-like embossed pattern on the label surface. No need for pre-embossing process
As a result, it has become possible to manufacture a labeled container in which the label and the container having a clear embossed pattern have a sense of unity with the cost reduction.

[Brief description of drawings]

FIG. 1 is a sectional view of a label used in the present invention, FIG. 2 is a front view of a mold, and FIG. 3 is a front view of a molded container. 1 ... Substrate, 2 ... Pattern layer 2 ... Adhesive layer, 4 ... Mold 5 ... Labeling surface, 6 ... Suction hole A ... Label

Claims (1)

[Claims] 1. A label having an adhesive layer exhibiting an adhesive effect at a molding temperature on a back surface of a base material at a position corresponding to a label sticking surface of a split type container, with the adhesive layer being inside, and the label is inserted. To a position corresponding to the label sticking surface of the mold, and then heat and soften a parison made of a resin having a shrinkage rate of 1.8% or more after molding and introducing it into the mold, and then closing the mold. After that, pressurized air is blown into the parison for blow molding, and a wrinkle-like embossed pattern is formed on the label surface as the molded container shrinks.