JPH07195595A - Manufacture of corrugated board base material - Google Patents

Abstract

PURPOSE:To provide a method for manufacturing a corrugated board base material of light weight and high rigidity which can be manufactured easily and allowed to subject to a deep draw forming. CONSTITUTION:In the manufacturing method for a corrugated board base material 1 with liners 3a and 3b disposed at least on one way face of a core 2 to be formed into the wavy shape, a foam raw material 16 is interposed between the core 2 and liners 3a and 3b in the preliminary process for bonding the core with the liners, and then the foam raw material 16 is heat foamed to fill, and form a foamed body between the liners 3a and 3b and the core 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a corrugated board substrate, and more particularly to a method for producing a corrugated board substrate having excellent rigidity and shape retention characteristics.

[0002]

2. Description of the Related Art FIG. 9 shows a basic structure of a corrugated board substrate. This corrugated board base material 51 is a corrugated core 5
2 and a liner 54 adhered to both sides of the core 52 with a thermoplastic resin coating 53 interposed therebetween. The liner 54 is relatively light and inexpensive and thus has a wide range of applications, for example, as a ceiling material for automobiles. It is used.

Many improvements have been made to such corrugated board base materials in accordance with the intended use. In relation to the present invention, glass wool (sound absorbing material) is placed between the core and the liner as disclosed in JP-A-58-177742. And the example in which a foamed resin for forming a heat insulating layer is injected and filled between the core and the liner as in Japanese Utility Model Laid-Open No. 56-135841.

[0004]

However, in the case of interposing glass wool between the core and the liner as in the former case, the filling operation must be performed while crushing the glass wool in the corrugated groove of the core. However, the filling workability is poor, it is difficult to uniformly fill the glass wool, and there is a problem in product performance. In the latter case, after the core and the liner are adhered, a foamed resin is interposed between them (from the injection hole provided in the liner for the one-sided liner, to the core for the double-sided liner). In addition, there is a problem that the workability of filling the foamed resin and uniform filling cannot be easily realized. Note that the corrugated board base material is often deep-drawn as in the case of a ceiling material for automobiles, and when such deep-drawing is performed, there is a problem that the moldability is likely to be impaired by the filler as described above. is there.

Therefore, an object of the present invention is to eliminate the above problems, to provide a method for manufacturing a lightweight and highly rigid corrugated board base material which is easy to manufacture and enables deep drawing. To do.

[0006]

In order to achieve the above-mentioned object, the present invention provides a method for producing a corrugated board base material, wherein a corrugated core is provided with a liner on at least one side of the corrugated core. Forming a foam by filling a foam between the liner and the core by interposing a foam raw material between the core and the liner in the preceding step and then heating and foaming the foam raw material. Is. In the above structure, the foam raw material can be placed in the corrugated groove of the core by using polypropylene foam beads. It is also possible to use a polypropylene-based foam sheet as the foam raw material and to dispose it on the side of the core when corrugating the core.

[0007]

According to the method of the present invention, when the foam raw material is interposed between the core and the liner, and the foam raw material is heated and foamed thereafter, the foam formed by filling between the liner and the core is formed. A corrugated cardboard substrate having is manufactured. Further, the rigidity and the like of the foam raw material can be easily changed by changing the expansion ratio and the like.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. 1 to 4 show a first embodiment of the present invention. FIG. 1 is a structural layout view showing an outline of a manufacturing apparatus used in the present invention, and FIGS. 2 and 3 explain a manufacturing method of the present invention. FIG. 4 is an external perspective view of a corrugated board substrate manufactured by the apparatus.

First, the corrugated board base material 1 produced according to the present invention.
The structure of the corrugated core 2 includes a corrugated core 2, a liner 3a adhered to one surface of the core 2, a liner 3b adhered to the other surface of the core 2, a core 2 and a liner 3a. A foam 4A filled and formed between the core 2 and the foam 4B filled and formed between the core 2 and the liner 3b are integrally provided.

Next, a method of manufacturing the corrugated board base material 1 and an example of its apparatus configuration will be described in detail with reference to FIGS. The manufacturing apparatus shown in FIG. 1 includes winding shafts 5a, 5b, 5c, upper and lower rolls 6, 7, feed rollers 8, 9, 10, a drying unit 11, a conveyor 12, a cutting unit 13, and the like. ing.
The core 2, the liners 3a, 3b are respectively corresponding winding shafts 5.
It is wound around and set on a, 5b, and 5c, and is sequentially drawn out from each of the winding shafts 5a, 5b, and 5c by a required amount at a predetermined rotation speed.

The core 2 wound around the winding shaft 5a has not yet been formed into a corrugated shape on the winding shaft 5a.
When it is pulled out from a and fed through between the upper roll 6 and the lower roll 7, the upper and lower rolls 6, 7
To form a continuous waveform. Further, the movement of the corrugated core 2 is transferred to the cutting section 13 by the conveyor 12 along with the rotation of the feed rollers 8, 9 and 10.

Between the upper and lower rolls 6, 7 and the feed roller 8 and between the feed roller 9 and the feed roller 10, the starch-based adhesive is placed in both corrugated grooves of the core 2 after corrugation. Sprayer 15a, 15b for spraying 14 respectively, and sprayer 17a, 17b for foam material for spraying polypropylene (PP) -based foam beads 16 as a raw material of foam 4A, 4B. Is provided. The sprayer 15a and the injector 17a are arranged to spray the starch-based adhesive 14 on one side of the core 2 after being corrugated and then spray the foam beads 16, and the sprayer 15b and the injector 17b are After the corrugated molding, the starch-based adhesive 14 is sprayed on the other surface side of the core 2, and then the foam beads 16 are sprayed.

A liner 3a wound around a winding shaft 5b.
After being drawn out from the winding shaft 5b, it is guided by the guide roller 18 and guided to the feed roller 8. On this feed roller 8, the application or spraying treatment of the starch adhesive 14 and the foam beads 16 is completed. The core 2 is superposed on one side of the core 2, and in the superposed state, the core 2 and the core 2 are fed in the direction of the cutting portion 13 with the feed rollers 9 and 10 and the carrier 12 interposed. Further, when the liner 3 a is overlaid on one side surface of the center core 2, part of the starch-based adhesive 14 attached to the corrugated top of the center core 2 adheres to the liner 3 a, and the liner 3 a and the center core 2 are separated from each other. The space is temporarily bonded.

The liner 3b wound around the winding shaft 5c
After being drawn out from the winding shaft 5c, it is guided by the guide roller 19 and guided to the feed roller 10, and on this feed roller 10, the starch-based adhesive 14 and the foam beads 16 are introduced.
The core 2 and the liner 3a are overlapped with the other side surface of the core 2 which has been applied or sprayed with
Along with the feed roller 10 and the conveyor 12, the cutting unit 13
Sent in the direction of. Also here, when the liner 3b is overlaid on the other side surface of the core 2, part of the starch-based adhesive 14 adhered to the corrugated top of the core 2 is part of the liner 3b.
Then, the liner 3b and the core 2 are temporarily bonded.

Therefore, in this manufacturing apparatus, the drying unit 1
1, the liner 3a, the core 2, and the liner 3b are superposed on each other, that is, at the part of the feed roller 10.
These are sent to the drying section 11 in a laminated state and integrated while passing through the drying section 11. In addition, the drying part 11 is low temperature drying, and is the temperature at least the foaming beads 16 do not heat-foam. FIG. 2 shows the layer state when passing through the drying section 11, and the expanded beads 16 are in the original state without being expanded yet, and the core 2 and the liners 3a, 3 are used.
It is in a state of being stored in the space between b. This state is referred to as a corrugated board material (1A) in the following description.

The cardboard material (1A) is a pulley 1
2a and 12b are sequentially transferred to a cutting machine 13 in a state of being sandwiched from above and below by a conveyor 12 having a belt conveyor 12c, and a predetermined size (for example, by a rotary cutter 13b on a table 13a in the cutting section 13 (for example, When used for automobile ceilings, it is cut into blanks.

Then, this corrugated board material (1A) is set in a heating molding die which is pressed into a product shape in the same manner as in the conventional case, the heating temperature is about 120 to 150 ° C., and the molding time is 20 to 20 ° C.
It is heat-molded under the condition of about 30 seconds. Then, the foam beads 16 in the corrugated cardboard material (1A) are heated to about 120 to 130 ° C., which is the temperature at which foaming starts, and are foamed in the space between the core 2 and the liners 3a and 3b. As shown in FIG. 3, the foams 4A and 4B are filled and formed between the core 2 and the liners 3a and 3b, and at the same time, the foams 4A and 4B partially adhere to the core 2 and the liners 3a and 3b. Then, the space between the core 2 and the liners 3a, 3b is the foam 4A,
Bonded at 4B. FIG. 3 is a schematic cross section of the corrugated board substrate 1 formed by heating and foaming the foam beads 16 in this manner.

In the method of the present invention, the foamed beads in the corrugated cardboard material (1A) are directly heated by using a heat ray lamp, a hot air fan or the like without using the above heat forming mold. 16 to about 120-13
It is also possible to heat-expand by exposing to 0 ° C. In this case, a heating unit for heat foaming may be installed in front of or behind the cutting unit 13 in FIG. Further, if small holes are formed in the liners 3a and 3b in the previous step of the heat foaming and hot air is easily introduced into the inside from the small holes, foaming in the corrugated board material (1A) is activated. It is possible to prevent the production of unexpanded beads and the like.

According to the first embodiment described above, the foam beads 16 which are the raw material for the foams 4A and 4B are housed between the core 2 and the liners 3a and 3b, and the core 2 and the liners 3a and 3b are accommodated.
When the foam beads 16 are heat-foamed after adhering with b, the foam 4A, between the liners 3a, 3b and the core 2 is formed.
The corrugated board substrate 1 filled with 4B can be easily obtained. And the corrugated board base material 1 made in this way
Then, between the liners 3a and 3b and the core 2, the foam 4
Since it is filled with A and 4B, this foam 4A and 4B
As a result, the rigidity is increased without increasing the weight. Also,
When the above-mentioned heat-molding die is used to form a predetermined shape, the foaming pressure of the foams 4A and 4B enhances the shape-retaining property, and wrinkles are less likely to occur in the curved shape portion. Furthermore, by changing the foam raw material, it is possible to easily obtain a corrugated board base material having different rigidity and strength. In addition, the foam bodies 4A and 4B function as a sound absorbing material, and can be used as the corrugated board base material 1 having a high sound absorbing effect.

5 to 7 show a second embodiment of the present invention. FIG. 5 is a schematic structural layout view of a manufacturing apparatus used in the present invention, and FIGS. 2 and 3 explain a manufacturing method of the present invention. FIG. The appearance structure of the corrugated board base material 1 manufactured in the second embodiment is almost the same as that of the corrugated board base material shown in FIGS. 3 and 4, and the corrugated core 2 and the inner core 2 shown in FIG. The liner 3a adhered to one side of the core 2 and the core 2
The liner 3b adhered to the other surface side, the foam 4A filled between the core 2 and the liner 3a, and the foam 4B filled between the core 2 and the liner 3b are integrally formed. Have

Next, a method of manufacturing the corrugated board base material 1 and an example of the construction of the apparatus will be described with reference to FIGS. In this manufacturing apparatus, the core 2 and the liners 3a and 3b are wound around the corresponding winding shafts 5a, 5b and 5c and set, and sequentially drawn out from the respective winding shafts 5a, 5b and 5c by a necessary amount. Further, the winding shaft 5 around which the core 2 is wound
Polypropylene (PP) -based foamed sheets 26a and 26b are wound around the winding shafts 5d and 5e and set at upper and lower positions with a sandwiched therebetween.

Further, the core 2 wound around the winding shaft 5a and the foamed sheet 2 wound around the winding shafts 5d and 5e.
6a and 26b have not yet been formed into a wavy shape on the respective winding shafts 5a, 5e and 5e, and the winding shafts 5a, 5d,
5e, and the upper and lower surfaces of the center core 2 are drawn out from the foam sheet 2
6a and 26b sandwiched between the upper roll 6 and the lower roll 7 and fed between the two rolls 6 and 7, when the rolls 6 and 7 roll the foamed sheets 26a and 26b. And the core 2 are formed into a continuous waveform. In addition, the core which is formed in a corrugated shape with the foamed sheets 26a and 26b in this way and in which the foamed sheets 26a and 26b are not yet foamed is referred to as "core 2a with foamed sheet" in the following description. Then, the core 2a with a foam sheet formed in a corrugated shape between the upper roll 6 and the lower roll 7 is transferred to the drying unit 11 side by the feed rollers 8, 9 and 10.

Further, between the upper and lower rolls 6, rolls 7 and the feed roller 8 and between the feed rollers 9 and 10, a starch-based adhesive 14 is provided on the surface of the foamed sheet core 2a. Adhesive sprayers 15a and 15b for spraying are provided. The atomizer 15
a is a starch-based adhesive 1 on one side of the core 2a with a foam sheet.
4 is sprayed, and the sprayer 15b is arranged to spray the starch-based adhesive 14 on the other surface side of the foamed sheet core 2a.

The liner 3a wound around the winding shaft 5b
After being pulled out from the winding shaft 5b, the core is guided by a guide roller 18 and guided to a feed roller 8 on which the starch-based adhesive 14 has been applied to finish the application of the starch-based adhesive 14. It is stacked on one side of 2a, and in this stacked state, it is transferred to the drying section 11 side by the feed rollers 9 and 10 together with the core 2a with a foam sheet. When the liner 3a is placed on one side of the foamed sheet core 2a, a part of the starch-based adhesive 14 attached to the corrugated top of the foamed sheet core 2a is attached to the liner 3a. A temporary bond is made between the foamed sheet-attached core 2a.

The liner 3b wound around the winding shaft 5c
Is drawn out from the winding shaft 5c, guided by the guide roller 19 and guided to the feed roller 10, and on this feed roller 10, the application process of the starch-based adhesive 14 is completed, and the core with a foam sheet is finished. The foamed sheet-containing core 2a and liner 3a are stacked on the other surface
At the same time, it is sent to the drying section 11 by the feed roller 10 and further transferred to the cutting section 13 by the transporter 12. Also here, when the liner 3b is overlaid on one side of the foamed sheet core 2a, part of the starch-based adhesive 14 adhered to the corrugated top of the foamed sheet core 2a adheres to the liner 3b, 3b and the core 2a with a foam sheet are temporarily bonded.

Therefore, in this manufacturing apparatus, the drying unit 1
1, the liner 3a, the foamed sheet core 2a, the liner 3
b are piled up, and these are sent to the drying section 11 in a laminated state and integrated while passing through the drying section 11. The drying unit 11 is a low-temperature drying device and has a temperature at which at least the foamed sheets 26a and 26b do not heat and foam. FIG. 6 shows a layer state when passing through the drying unit 11, and the foamed sheets 26a and 26b are in the original sheet state without being foamed yet. This state is referred to as a corrugated board material (1B) in the following description.

The corrugated board material (1B) is a pulley 1
The carrier 12 having a belt conveyor 12c driven by 2a and 12b is sequentially transferred from a state of being sandwiched from above and below to a cutting machine 13, and a predetermined size (for example, by a rotary cutter 13b on a table 13a at a cutting section 13 (for example, When used for automobile ceilings, it is cut into blanks.

Then, this corrugated board material (1B) is set in a heat molding die which is pressed into a product shape in the same manner as in the conventional case, the heating temperature is about 120 to 150 ° C., and the molding time is 20 to 20 ° C.
It is heat-molded under the condition of about 30 seconds. Then, the foam sheets 26a and 26b forming the corrugated board material (1B).
Are heated to about 120 to 130 ° C., which is the temperature at which foaming starts, and each foams so as to fill the space between the core 2 and the liners 3a and 3b. As a result of this foaming, as shown in FIG. The foams 4A and 4B are filled and formed between the liners 3a and 3b, and at the same time, a part of the foams 4A and 4B are attached to the core 2 and the liners 3a and 3b, so that the core 2 and the liner 3a, The spaces 3b are adhered to each other with foams 4A and 4B. FIG. 7 is a schematic cross section of the corrugated board substrate 1 obtained by heating and foaming the foamed sheets 26a and 26b in this manner.

In the method of the present invention, the foamed sheet in the corrugated cardboard material (1B) is heated by directly heating the corrugated cardboard material (1B) using a heat ray lamp, a hot air fan, etc. without using the above heat forming mold. Approximately 1 for 26a and 26b
It is also possible to heat-expand by exposing to 20-130 degreeC. In this case, a pinching type heating part for heat foaming may be installed in front of or behind the cutting part 13 in FIG. Further, if small holes are formed in the liners 3a and 3b in the previous step of the heat foaming and hot air is easily introduced into the inside from the small holes, foaming in the corrugated board material (1B) is activated. Therefore, the non-foaming factor can be eliminated.

According to the second embodiment described above, a corrugated cardboard material (1B) was produced in which the foam sheets 26a and 26b, which are the raw materials of the foams 4A and 4B, were housed between the core 2 and the liners 3a and 3b. After that, when the foamed sheets 26a and 26b are heat-foamed, the corrugated board base material 1 in which the foamed bodies 4A and 4B are filled between the liners 3a and 3b and the core 2 can be easily obtained. Then, in the corrugated board base material 1 thus produced, as described in the first embodiment,
Foams 4A, 4B between the liners 3a, 3b and the core 2
Since the foams 4A and 4B are filled with, the rigidity can be increased without significantly increasing the weight. Further, in the case where the above-mentioned heat-molding die is used to form a predetermined shape, the foaming pressure of the foamed bodies 4A and 4B enhances the shape-retaining property, and it is difficult for wrinkles or the like to occur in the curved shape portion. Become. Furthermore, by changing the foam raw material, it is possible to easily obtain a corrugated board base material having different rigidity and strength. In addition, foam 4
A and 4B function as a sound absorbing material, and can be used as the corrugated board base material 1 having a high sound absorbing effect.

In each of the above embodiments, the corrugated board substrate 1
In the above description, the liner 3a, 3b is provided on both sides of the core 2, but in the present invention, the liner 3a is provided on only one side of the core 2.
Alternatively, a type provided with 3b can be similarly applied.

[0032]

As described above, according to the method for producing a corrugated board base material of the present invention, the foam raw material is interposed between the core core and the liner in the preceding step of adhering the core and the liner, and thereafter the foam raw material is used. By heat-foaming, the corrugated board base material in which the foam is filled and formed between the liner and the core can be easily obtained. Further, by changing the foam raw material, it is possible to easily obtain a corrugated board base material having different rigidity and the like.

[Brief description of drawings]

FIG. 1 is a schematic configuration layout diagram showing a manufacturing apparatus used in a first embodiment of the present invention.

FIG. 2 is a diagram for explaining the manufacturing method of the first embodiment using the above apparatus.

FIG. 3 is a diagram for explaining the manufacturing method of the first embodiment using the above apparatus.

FIG. 4 is a perspective view showing an appearance example of a corrugated board substrate manufactured by the method of the present invention.

FIG. 5 is a schematic configuration layout diagram showing a manufacturing apparatus used in a second embodiment of the present invention.

FIG. 6 is a diagram illustrating a manufacturing method of the second embodiment using the apparatus.

FIG. 7 is a drawing for explaining the manufacturing method of the second embodiment using the above apparatus.

FIG. 8 is a sectional view showing a basic structure of a general corrugated board substrate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Corrugated board base material 2 Core 3a Liner 3b Liner 4A Foam 4B Foam 12 Transporter 13 Cutting part 16 Foam beads (foam raw material) 26a Foam sheet (foam raw material) 26b Foam sheet (foam raw material)

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location B32B 27/32 Z 8115-4F // B29K 23:00 105: 04

Claims (3)

[Claims] 1. A method for producing a corrugated board substrate comprising a corrugated core provided with a liner on at least one side of the corrugated core, wherein foaming is performed between the core and the liner in a preceding step. A method of manufacturing a corrugated board base material, comprising: interposing a body raw material; and thereafter, foaming the foam raw material by heating to fill and form the foam between the liner and the core. 2. The method for producing a corrugated board substrate according to claim 1, wherein the foam raw material is polypropylene-based foam beads, which are placed in the corrugated groove of the core. 3. The method for producing a corrugated board substrate according to claim 1, wherein the foam raw material is a polypropylene-based foam sheet, and the foam raw material is arranged on the core side when corrugating the core.