JPH0247007Y2 - - Google Patents

Description

[Detailed description of the invention] <Technical field> This invention relates to molded composite sheets, and is used to mold and manufacture cushioning packaging materials such as packaging boxes, packaging containers, and packaging frames for storing and cushioning various items. It relates to a composite sheet for molding, which is a laminated layer of foamed sheet and paperboard.

<Prior art> If a composite sheet consisting of a foamed sheet of thermoplastic resin such as expanded polystyrene sheet and paperboard such as cardboard is used as a cushioning packaging material, it is possible to achieve the excellent cushioning properties of the foamed sheet and the excellent cushioning properties of paperboard. Printability, stiffness, etc. can be effectively combined, resulting in an extremely excellent product. In particular, if the foamed sheet side is formed with bulges and projections to protect the packaged article, the cushioning and protection performance for the packaged article will be even better.

As a buffer packaging material made of the above-mentioned composite sheet material and a method for manufacturing the same, the inventors of the present application previously
A patent application No. 58-49461 (see Japanese Patent Application Laid-open No. 59-174467) has been filed.

In the above-mentioned prior art, a composite sheet is formed by joining a paperboard to a sheet molded body in which an uneven shape is formed by thermoforming a foamed sheet in advance. That is, if the foam sheet and paperboard are laminated first, it will not be possible to form the uneven shape only on the foam sheet, so before joining the foam sheet and paperboard, the uneven shape is formed on the foam sheet side. I try to keep it that way.

Therefore, according to the above-mentioned prior art, forming an uneven shape on a foam sheet can be easily performed in exactly the same way as conventional sheet forming, but adhesive bonding of a foam sheet formed into an uneven shape and a flat paperboard is difficult. This is difficult, and when pressing the foam sheet and paperboard together for adhesive bonding, it is necessary to avoid the protruding portions of the foam sheet. As a result, there are drawbacks such as a complicated press device for crimping, a possibility of poor bonding between the foam sheet and the paperboard, and high manufacturing costs, and improvements have been desired.

<Purpose> Therefore, the purpose of this invention is to solve the above-mentioned problems of the prior art and provide a composite sheet in which a foam sheet and a paperboard are bonded in advance, and furthermore, a cushioning packaging is provided by forming an uneven shape only on the foam sheet. An object of the present invention is to provide a moldable composite sheet that can be manufactured into a molded material.

<Structure> The structure for achieving the above purpose is that a thermoplastic resin foam sheet and a paperboard with a large number of small ventilation holes formed therethrough are integrally joined using a large number of partial adhesive parts. It is characterized by

<Example> Next, an example of this invention will be described below with reference to the drawings.

First, as shown in FIG. 1, the composite sheet S is made by bonding a foamed sheet 1 made of thermoplastic resin such as a foamed polystyrene sheet and a paperboard 2 such as cardboard in the form of many dots or lines. They are integrally joined by a portion 3 and laminated. and,
A large number of ventilation holes 20 are formed through the paperboard 2 over its entire surface.

As the foamed sheet 1, in addition to polystyrene, foamed sheets made of high-impact polystyrene, polyvinyl chloride, and other various thermoplastic resins used in ordinary packaging materials can be used. The thickness of the foamed sheet 1 varies depending on the application, but is usually about 0.2 to 2.0 mm. Further, as the foamed sheet 1, it is also possible to use one in which a non-foamed synthetic resin film is laminated on one or both sides.

The paperboard 2 may be paperboard, coated paper, art paper, etc., which have been conventionally used as packaging paper.
Various paper materials can be used. It is preferable to form a printed pattern on the outer surface of the paperboard 2 or use a pre-colored paperboard for a good appearance. In addition, the thickness of the paperboard 2 is appropriately thick depending on the use of the cushioning packaging material and the thickness of the foam sheets 1 to be laminated.
It is necessary that the paperboard 2 has shape retention properties to the extent that the foamed sheet does not deform when the paperboard 2 is subjected to expansion molding. The ventilation amount of the small ventilation holes 20 formed in the paperboard 2 changes depending on the hole diameter and formation density, and when the foam sheet 1 is vacuum formed, a sufficient amount of air can be supplied to the inner space described below. Normally, the pore size is 0.5
~2 mmφ, and the formation density is 10 to 15 small holes per ¹ cm2 when the hole diameter is small.
0 may be formed through the hole.

Next, the partial adhesive portions 3 are formed to avoid the position where the expansion molding is performed during vacuum forming, which will be described later, and are formed between the foam sheet 1 and the foam sheet 1 at intervals wider than the formation intervals of the small ventilation holes 20. After applying adhesive partially in dots or lines on the contact surface with the paperboard 2,
A foamed sheet 1 and a paperboard 2 are pressure-bonded to form a composite sheet S. The shape of the partially bonded portion 3 may be a dot shape such as a small circle, a square shape, or a cross shape, or a linear shape such as parallel or lattice-like continuous lines or interrupted lines. 2 can be reliably joined to each other, and the shape and arrangement can be freely changed and implemented as long as they do not interfere with vacuum forming, which will be described later. Note that, as the adhesive, a normal thermal adhesive or the like that has been conventionally used for bonding the foam sheet 1 and the paperboard 2 can be used.

A method of thermoforming the foamed sheet 1 side using the composite sheet S having the above structure is shown in FIGS. 2 to 4.

First, among the forming apparatuses shown in FIG. It makes it convenient. and,
Sequentially pull out the composite sheet S from the roll 4,
The molding process is performed while moving in a fixed direction.

5 is a heating section, which is equipped with a heating mechanism such as an electric heater, and is especially suitable for the foam sheet 1 among the composite sheets S.
The sides are heated and softened to a forming temperature that allows thermoforming.

6 is a molding section, in which a concave vacuum forming mold 60 corresponding to a predetermined molding shape is provided on the foam sheet 1 side of the composite sheet S, and the paperboard 2 side is open. Then, with the composite sheet S in contact with the mold 60, the heated and softened foamed sheet 1 is subjected to vacuum forming. That is, the foamed sheet 1 is drawn into the mold by vacuum suction from the vacuum suction holes 61 formed on the mold surface of the mold 60, and the heated and softened foamed sheet 1 is drawn along the inner surface shape of the mold. The bulging convex portion 10 is formed by bulging and deforming.

Note that when the foamed sheet 1 is bulged and deformed to form the bulged convex portion 10, a space H corresponding to the shape of the back surface of the bulged convex portion 10 is created between the foamed sheet 1 and the paperboard 2, which were initially in close contact with each other. However, air is supplied to this space H from the outside through the ventilation holes 20 of the paperboard 2.

In the vacuum forming of the foamed sheet 1, the shape and arrangement of the bulging convex portions 10 can be freely changed as needed; however, the bulging convex portions 1
No. 0 cannot be bulge-molded unless it is formed at a location where the foam sheet 1 and the paperboard 2 are not joined. Therefore, as described above, the partial adhesive part 3 where the foam sheet 1 and the paperboard 2 are joined in the composite sheet S should be formed in advance, avoiding the part (position) where the expansion molding is to be performed. This makes it possible to form the bulging convex portion 10 in vacuum forming.

Next, 7 is a trimming section, and in the forming section 6, the composite sheet S in which the bulging convex portions 10 are formed on the foam sheet 1 side is trimmed and cut to a predetermined outer shape of the cushioning packaging material. The cushioning packaging material is completed by forming folding lines and perforations for separation according to the requirements.

Through the above molding equipment and molding process,
A cushioning packaging material in which a bulging convex portion 10 is formed on the foamed sheet 1 side is manufactured from a flat composite sheet S, but as described above, while continuously running a long composite sheet S, The molding process can be done very efficiently. However, it is also possible to cut the composite sheet S into veneer shapes and then mold them one by one.

Next, FIGS. 5 and 6 show a box-shaped container 8 as an example of a buffer packaging material formed by the above manufacturing method using the composite sheet S of this invention, with a bottom plate 80 A side plate 81 is formed in a row around the periphery so that it can be raised freely, and a cover plate 8 is attached to the end of the side plate 81.
2 are arranged in a row in a bendable manner, and a side plate 8 is provided around the bottom plate 80.
1 is bent and raised, and then a lid plate 82 is bent and covered inward from a side plate 81 to form a rectangular parallelepiped-shaped box container 8. The foamed sheet 1 on the inner surface of the container 8 is provided with a bulging convex portion 10 for cushioning and protecting the packaged article A to be placed in the container by contacting the packaged article A.

Therefore, when manufacturing the box container 8, first a predetermined bulging convex portion 10 is formed on the foamed sheet 1 side of the composite sheet S, and the folding lines between the bottom plate 80 and the side plate 81, and the side plate 81 and the lid plate 82 are formed. Press to form or
Box container 8 in unfolded state with trimmed external shape
After forming, the three-dimensional box container 8 is manufactured by bending and assembling each plate 80.

In the case of the box/container 8 described above, by abutting the bulging convex portion 10 of the foam sheet 1 around the packaged article A, the packaged article A can be protected with extremely good cushioning properties, and the outer surface of the box/container 8 can be protected. Since the paperboard 2 is exposed, it is easy to print and color and has a beautiful appearance.As in the past, it is stored in a cushioning packaging material made of foam sheet and then double wrapped in an outer case such as a paper box. This will significantly reduce the time and cost required.

Furthermore, FIG. 7 shows a packaging frame 9 that accommodates and protects a plurality of packaged articles A at the same time. Frame pieces 90 and the like that contact the upper and lower surfaces of the packaged articles A are folded around the packaged articles A. The packaged article A is wrapped in a packaging frame 9 to protect it, and the expanded convex portion 10 of the foamed sheet 1 is formed on the inner surface of the frame piece 90.
is used as a partition between a plurality of packaged articles A.

In addition to the box container 8 or packaging frame 9 shown above, the cushioning packaging material manufactured from the composite sheet S of this invention includes various packaging boxes, packaging containers, packaging frames, packaging trays, and others. It can be freely applied to various packaging materials.

<Effects> As described above, according to the composite sheet S of this invention, a flat foam sheet 1 and a paperboard 2 are adhesively bonded to each other by dotted or linear partial adhesive portions 3. A flat composite sheet S is formed into a foamed sheet to form bulging convex portions 10.

That is, when performing vacuum forming on the foamed sheet 1 side of the composite sheet S, the foamed sheet 1 side is brought into contact with the vacuum forming mold 60, and vacuum suction is applied from the outer surface of the foamed sheet 1 to form the mold shape. However, if the foam sheet 1 and the paperboard 2 are joined together over the entire surface, it is impossible to bulge and deform only the foam sheet 1. Therefore, the foam sheet 1 and the paperboard 2 are adhesively bonded to each other using partial adhesive parts 3 in the form of dots or lines, and the bulging convex parts 10 are connected to the foam sheet 1 and the paperboard 2 other than the partial adhesive parts 3. By forming the protrusions 10 at a position where they are not joined, it is possible to vacuum form the protrusions 10 only on the foamed sheet 1 even though the paperboard 2 is present.

Moreover, when the foam sheet 1 is vacuum-suctioned to the outer surface side to cause it to bulge and deform, a space H corresponding to the shape of the bulge convex portion 10 is created on the contact surface between the foam sheet 1 and the paperboard 2 which are in close contact with each other. must be formed;
A vacuum portion is generated between the foam sheet 1 and the paperboard 2, which causes problems such as the foam sheet 1 being unable to bulge and deform, and the shape of the bulging convex portions 10 being unable to be formed accurately. However, if the composite sheet S of this invention is used, since a large number of ventilation holes 20 are formed in the paperboard 2, air is supplied from these holes 20 to the space H side, and the foam sheet 1 is Vacuum forming can be performed very smoothly.

As described above, the foam sheet 1
It becomes possible to form the bulging convex portions 10 by performing vacuum forming only on the sides, and moreover, extremely good forming can be performed, which is no different from vacuum forming of the foam sheet 1 alone. Therefore, the manufactured cushioning packaging material can be freely formed even with the bulging convex portions 10 having a complicated shape, and it is possible to sufficiently exhibit the cushioning and protection performance for the packaged article.

Then, the foam sheet 1
The bonding work can be carried out using the flat foam sheet 1 and the paperboard 2 without being adversely affected by the uneven shape of the paperboard.The work is extremely easy, and the bonding can be done reliably and firmly.As a manufactured cushioning packaging material, , it is possible to manufacture a product with excellent integrity between the foam sheet 1 and the paperboard 2 and excellent durability.

In addition, the device for joining the foamed sheet 1 and the paperboard 2 used to manufacture the composite sheet S has no relation to the shape of the bulging convex portions 10 of the foamed sheet 1, and is used to join ordinary flat sheets together. Since a bonding device can be used, there is a great effect in simplifying the bonding device and reducing costs.

Furthermore, since the vacuum forming of the foam sheet 1 can be performed in exactly the same way as conventional vacuum forming methods or vacuum forming equipment, there is no need to worry about the forming equipment becoming complicated or the forming process being time-consuming, and the entire cushioning packaging material can be manufactured. It is possible to provide a moldable composite sheet S that exhibits various excellent practical effects, such as being able to reduce costs and improve manufacturing efficiency.

[Brief explanation of the drawing]

The figure shows an embodiment of the invention.
The figure is a cross-sectional view of the composite sheet, Figure 2 is a schematic structural diagram of the vacuum forming apparatus, Figure 3 is an enlarged cross-sectional view in the forming process, Figure 4 is a partially enlarged cross-sectional view of the manufactured cushioning packaging material, and Figure 5 The figure is a perspective view showing an example of the cushioning packaging material, FIG. 6 is a sectional view, and FIG. 7 is a sectional view of a further modified example. S...Composite sheet, 1...Foam sheet, 10...
...bulging convex portion, 2...paperboard, 20...small ventilation hole,
3... Partially bonded portion, 60... Vacuum forming mold.

Claims (1)

[Claims for Utility Model Registration] 1. A composite material for molding, characterized in that a foamed sheet of thermoplastic resin and a paperboard having a large number of ventilation holes formed therethrough are integrally joined at a number of partial adhesive parts. sheet. 2. The composite sheet for molding according to claim 1 of the above-mentioned utility model registration claim, in which the partial adhesive portions are formed in the form of dots. 3. The composite sheet for molding according to claim 1 of the above-mentioned utility model registration claim, wherein the partially bonded portion is formed in a linear shape.