JPH0529500Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a heat-sealable film composite and a multilayer display card using the same.

(Prior art) A cover sheet having an easily peelable transparent film is adhered to the surface of a card or label to cover the display on the surface, and the cover sheet is removed as necessary to display the display. BACKGROUND OF THE INVENTION Cards or labels with exposed covering sheets are known from the prior art.

For this type of card or label, for example, a transparent composite film made by releasably fusing different types of thermoplastic resins to each other is formed on the back side of a cover sheet, and when this sheet is peeled off after being adhered to a card mount. A film in which peeling always occurs between films is functionally superior and is used practically in many fields (such as Utility Model Application No. 61-204729).

(Problem to be solved by invention) What is extremely important in such a card with a cover sheet is that the pair of films constituting the composite film can be easily peeled off from the composite surface when necessary, and especially that it can be peeled off at any time. It must be tightly bonded so that it will not easily peel or shift when handled. Particularly in the case of postal cards, if the cover sheet were to peel off from the card during handling, there would be no point in using the cover sheet, and there is a risk that the card itself would not be accepted as a postal item.

It is difficult to achieve these conditions only by optimizing the peel strength of the composite film, so in reality, the peel strength of the composite film is set to be slightly weaker, and at the same time heat sealing etc. is applied to the periphery. During regular handling, the composite end face of the film is applied so as not to be peeled off or the like. However, this requires a step of applying heat sealing to the completed covering sheet again. In addition, as the thermoplastic resin material on one side of the composite film, materials such as polyethylene terephthalate are used in consideration of its releasability, but these materials have a relatively high melting point and are often difficult to heat seal. A high sealing temperature is required to achieve complete fusion at the end faces.

In other fields where this type of card is in demand, it is also desired to provide a multilayer display card that can be shipped as is without pasting or other operations after printing individual data on the card.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a peelable film composite of materials and construction that allows for reliable and easy heat sealing.

Another object of the present invention is to provide a more practical multilayer display card obtained using such a film composite.

Still another object of the present invention is to provide a multi-layer display card that allows card processing operations such as gluing and pasting to be omitted as much as possible on the user side as a card consumer.

(Means for Solving the Problems) The main object of the present invention is to provide a composite film consisting of a pair of thermoplastic resin film layers that are releasably fused to each other, and a covering sheet having a heat-sensitive adhesive layer on the back side. At least one edge of one resin film of the composite film is removed to expose a corresponding edge of the other resin film, and the heat-sensitive adhesive layer is heat-fused to the composite film. This is achieved by a heat-sealed film composite characterized in that a heat-sealed region is formed to cover the mutually fused end surfaces of the resin films.

The composite film used in such a film composite is preferably formed by laminating and pressing films obtained by heating and melting an EVA composition comprising 3 to 18% by weight of vinyl acetate and the balance being ethylene. The molding process of this film is particularly
Preference is given to using inflation molding at a temperature of 120 to 210°C followed by crimping flattening.

Another object of the present invention is achieved by a coated multilayer display card comprising the film composite adhered to a card substrate via a pressure sensitive adhesive.

Still another object of the present invention is achieved by a composite display card in which a heat-sensitive or pressure-sensitive coloring layer is formed on the surface of a card base material.

(Function) A covering sheet is fused and fixed to the pair of fused thermoplastic resin films constituting the film composite by a heat-sensitive adhesive layer, and the edge of one of the composite films is removed. At the exposed edge of the other film, the heat-sensitive adhesive reliably covers a predetermined area of the fused end surfaces of both films and fuses them to form a heat-sealed area; This completely prevents the composite film from peeling off from the composite end face. Further, the heat-sensitive adhesive easily melts at a temperature of 80 to 120°C, and its heat fusion can be easily carried out at a much lower temperature than in the above-mentioned usual case.

In addition, the covering sheet itself with a heat-sensitive adhesive layer formed on the back side is easily available as a heat-sensitive adhesive tape, etc., and the heat sealing is simultaneously formed in the process of integrating the covering sheet with the composite film by heat bonding. be done.

In this case, if a two-layer film obtained by compressing and flattening an inflation molded product of an EVA composition is used as the composite film, the production itself becomes extremely simple, and the removal process of the edges for forming a heat seal can be done by slitting, etc. By using this method, it can be easily performed at the same time as the flattening process.

In addition, a card made by adhering such a film composite can be heat-sealed to prevent it from peeling off from its edges, and the composite film can be peeled off along the cut-off line provided inside the seal. The composite end face is exposed and peeling can be easily performed using this area.

In addition, if a heat-sensitive or pressure-sensitive coloring layer is formed on the surface of the card base material, after the card is completed, the user can print the inner base material from the front side of the card using a thermal printer, dot impact printer, etc. Display can be performed on the surface by heat-sensitive or pressure-sensitive color printing.

Such a heat-sensitive color former or pressure-sensitive color former layer may be formed on the back surface of the covering sheet. In the case of a heat-sensitive coloring agent, it is preferable that its coloring temperature is sufficiently lower than the heat-sensitive temperature of the heat-sensitive adhesive layer.

Embodiments The present invention will be explained below with reference to specific embodiments shown in the drawings.

1 and 2 are enlarged sectional views of the film composite of the present invention and a multilayer display card using the same, respectively, and FIG. 3 shows a part of the manufacturing process of the composite film. It is an explanatory diagram.

First, to explain about Figure 3 showing an example of manufacturing a composite film, it contains 10% by weight of vinyl acetate.
MI (melt index) = 1.0g/10min EVA
A copolymer (manufactured by Asahi Kasei Corporation, trade name: EF1010) is heated and melted at a temperature of approximately 130°C in a screw cylinder (not shown) with a diameter of 40 cm in an inflation molding machine, and then it is extruded from a ring die as shown in Figure 3. as thick as
A 50 μm film F was formed into a hollow cylinder by inflation molding.

The formed cylindrical film F is pressed onto a bag-like object with a width of about 14 cm by pressing rollers R and R above the cooling zone, and the opposing cylindrical walls are fused together to form a composite consisting of two layers of films 2 and 3. It was left to cool as Film 1.

At the same time as this crimping process, both side edges 2S of the film 2 above the film 1 were continuously cut out with a width of about 3 mm using a slitter.

The composite film 1 shown in FIG. 1 is bonded at a pressure bonding surface (composite surface) P with a strength of approximately 10 to 20 g/cm (180° peel strength). This peel strength is about a few tenths of that of ordinary pressure-sensitive adhesives, and it can be easily peeled off, but on the other hand, it can also be accidentally peeled off if some kind of force is applied to the crimped end surface P from outside the card. There is a risk of it happening.

For this reason, in this embodiment, as described above, the slits are continuously removed from both side edges 2S of the film 2 above the composite film 1 along the flow direction, thereby exposing the side edges of the film 3 below. Figures 1 and 2).

Next, we made a film with the same dimensions and thickness as this composite film.
Heat-sensitive adhesive 6 (trade name: Thermofilm: melting point 80°C, thickness 40 μm) adhered to the back side of high-quality paper 4 as a 100 μm covering sheet with pressure-sensitive adhesive 5 is covered from above this composite film 1. It is heated to about 90° C. to fuse and integrate with the upper surface of the upper film 2, and the portion including the boundary of the crimping surface P between the side edges of the upper film 2 and the exposed lower film 3 is heated to about 90°C. Heat seal areas 6 and 7 are formed on the side edges by fusing.

Such a composite film 1 is used for various purposes by making use of the state in which a pair of films 2 and 3 are releasably fused together, but usually the lower film 3 is fused as shown in FIG. It is used by forming a pressure-sensitive adhesive layer 8 on the back surface and attaching it to a base card 9 as an adherend. In the figure, 10 is a cutoff line when the card is peeled off.

In such a card, for example, a film composite is applied to a pressure-sensitive adhesive layer 8 on a base card 9 having an address printed on the back side and a predetermined message printed on the front side.
Adhere by Appropriate printing can also be applied to the front side of the high-quality paper 5 of the covering sheet in advance, if necessary.

In such a card, the writing on the surface of the base card 9 is always hidden by the high quality paper 5 of the film composite. In this case, the high-quality paper 5 and the base card 9 are fixed to the composite film 1 by a heat-sensitive adhesive layer 4 and a pressure-sensitive adhesive layer 8, respectively.
Further, the film 2 and 3 of the composite film 1 is maintained at the above-mentioned appropriate peel strength. In particular, the side edges of the films 2 and 3 are heat-sealed with the heat-sensitive adhesive 4, and the crimped (composite) end surface P between the films 2 and 3 is completely covered, so the composite surface P There is no possibility of severe peeling.

When the recipient of the card reads the description on the base card 9, first, for example, the heat seal side edge 7 is cut off from the card base 9 along the tear line 10, or the films 2 and 3 of the composite film 1 are fused together. This portion is bent along the perforation line 10 that reaches the surface P to create a split.

Then, in this part, there is a composite surface P between films 2 and 3.
Since this portion is exposed, the films 2 and 3 can be easily separated from each other along the composite surface P by using this portion as a tightening tool for peeling off. As a result, the remaining part of the film composite can be removed with the transparent film 3 adhered to the base card 9.

In this way, in this example, a relatively low melting point
Since the heat-sealing areas 6 and 7 are formed by heat-sealing the heat-sensitive adhesive layer 4 to the EVA films 2 and 3, the heat-sealing process can be performed extremely easily and reliably. .

Further, since the heat sealing of the films 2 and 3 is performed not on their end faces but over the stepped portions of the films 2 and 3 including the exposed portion of the composite end face P, the heat sealing becomes extremely reliable and strong.

Furthermore, since this heat-sealing step is carried out simultaneously with the processing for bonding the composite film 1 with the high-quality paper 5 as a covering sheet, the heat-sealing step does not become particularly complicated.

In another embodiment of the present invention, as shown in FIG. 4, a heat-sensitive coloring agent layer 11 is previously formed on the surface of the card base material 9, and the high-quality paper 5 is coated at any time after the card is completed. By performing thermal printing from the front side using a thermal printer or the like, it is possible to obtain a print that is always hidden by the high-quality paper 5 on the corresponding portion of the card base material.

As long as the heat-sensitive temperature of this color-forming layer 11 is made sufficiently higher than the heat-sealing temperature, this color-forming layer will be at a temperature at the time of heat-sealing (for example, about 90°C).
Since coloring does not occur due to coloring, there is no great difficulty in selecting a heat-sensitive coloring layer.

Similarly, the heat-sensitive coloring agent layer 1 on the surface of the card base material 9
Similar results can be obtained even if pressure-sensitive color former layer 12 is used in place of layer 1. In this case as well, the user can perform pressure-sensitive color printing of information by printing on a predetermined position from the outside of the card delivered as a finished product using a dot printer or the like.

In conventional cards of this type, including the embodiment shown in FIG. There were some inconveniences such as having to outsource the pasting work. However, according to the embodiment shown in FIG. 4, all data requiring confidentiality can be input easily by the user using an ordinary heat-sensitive or pressure-sensitive printing printer.

Of course, the pressure-sensitive coloring agent layer and the heat-sensitive coloring agent layer can be formed anywhere within the card layer, for example, on the back surface of the high-quality paper 4 of the film composite.

As the covering sheet, paper such as high-quality paper is preferable in terms of processability, printability, hiding power, etc., but aluminum foil etc. can also be used, and in order to ensure the bond between the sheet and the heat-sensitive adhesive. An anchor coat such as polyethylene may be applied to the surface. Furthermore, heat sealing may be applied to the upper and lower films along the fused end surfaces.

(Effects of the invention) As described above, according to the invention, it is possible to extremely easily heat seal the edges of a layered card, etc.

[Brief explanation of the drawing]

Fig. 1 is an enlarged sectional view of one embodiment of the present invention;
The figure is an enlarged cross-sectional view of a card using the above embodiment of the present invention, Figure 3 is a diagram showing the manufacturing process of a composite film used in the present invention, and Figure 4 is an enlarged cross-sectional view of yet another embodiment of the present invention. It is. 1... Composite film, 2, 3... Film (EVA film), 4... Heat sensitive adhesive, 5...
High quality paper, 6, 7... Heat seal area, 8... Pressure sensitive adhesive layer, 9... Base card, 10... Cutting line, 11... Heat sensitive color former layer, 12... Pressure sensitive color former layer .

Claims (1)

[Claims for Utility Model Registration] (1) A composite film 1 consisting of a pair of thermoplastic resin films 2 and 3 that are releasably fused to each other.
and a covering sheet 5 having a heat-sensitive adhesive layer 4 on its back surface, and removing at least one edge of one of the resin films 2, 3 of the composite film 1 and removing the other resin film 3, 2. the heat-sensitive adhesive layer 4 with the corresponding edge exposed;
A heat-sealable film composite, characterized in that heat-sealed areas 6 and 7 are formed by heat-sealing the resin films 2 and 3 to the composite film 1 and covering the mutually fused end surfaces of the resin films 2 and 3. (2) The composite film 1 contains a composition containing 3 to 18% by weight of vinyl acetate and the balance ethylene.
2. The heat-sealable film composite according to claim 1, which is formed by heat-forming into a hollow cylindrical shape by inflation molding at ~210[deg.] C., and by fusing and integrating opposing cylindrical walls with each other. (3) A multilayer display card formed by adhering the film composite according to claim 1 or 2 to a card base material 9 via a pressure-sensitive adhesive. (4) Heat-sensitive coloring layer 11 on the surface of the card base material 9
4. The multi-layer display card according to claim 3, wherein the multi-layer display card is formed with:. (5) Pressure-sensitive coloring layer 12 on the surface of the card base material 9
4. The multi-layer display card according to claim 3, wherein the multi-layer display card is formed with:. (6) A pressure-sensitive coloring layer 12 is provided on the back side of the covering sheet 5.
4. The multi-layer display card according to claim 3, further comprising: a multi-layer display card.