JPS6350118Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to reinforced cardboard. Corrugated cardboard has appropriate strength and cushioning properties, and is lightweight and easy to handle, so it has come to be widely used as a variety of packaging materials. When stored in boxes, there was a problem in that the side walls were prone to bending due to the pressure when the boxes were stacked high. Conventionally, in order to prevent this, the solution was to use multiple core structures such as multi-sided corrugated cardboard or multi-sided corrugated cardboard, but this not only resulted in extremely high prices, but also due to the increased thickness of the corrugated cardboard. ,
When loaded on a truck as a packaging box for goods, there is a disadvantage that it becomes bulky and the number of items that can be loaded is greatly reduced, and it is also necessary to carve a V-shaped notch along the fold line to assemble the box. There were also some inconveniences.

Therefore, the inventors attempted to strengthen the corrugated cardboard by incorporating metal foil such as aluminum foil or steel foil into the corrugated structure, but the steel foil in particular is rolled, so the cut surface is rough. The metal foil is extremely sharp and there is a risk of injury to hands while handling the cardboard box, and the technical limit to which the thickness of conventional metal foil can be reduced is approximately 80μ.
In particular, when steel foil is used, there are problems such as being hard and having poor workability, as well as being unsuitable for reducing the weight of corrugated cardboard boxes.

This idea was developed after extensive experimentation and research to solve the above problems, and it was discovered that by using a certain type of metal foil, the strength of corrugated cardboard can be greatly increased without losing its advantageous properties. We were able to successfully obtain the desired reinforced cardboard.

Next, an embodiment of this invention will be described based on the drawings.

Figures 1 to 4 show a partially reinforced corrugated board according to this invention and an example of its use. Front and back liners 3 and 4 sandwiching the core 1 are provided with a reinforcing layer 2.
Among them, the front liner 3 is adhered to the reinforcing layer 2, and the reinforcing layer 2 is made of electrolytic iron foil.

Electrolytic iron foil is a thin pure iron foil made by solidifying iron powder using an electroforming method.Due to the characteristics of the manufacturing process, the minimum thickness that can be achieved with conventional rolled foil is approximately 80μ. The limit of electrolytic iron foil is about 20μ, and its cut surface is less sharp than that of rolled foil, and it is extremely easy to deform plastically. Furthermore, since no impurities are mixed in during the electrolytic process, the surface is clean, and the adhesive has various properties such as good ``glue'' even if the surface degreasing process is omitted.

This reinforcing layer of electrolytic iron foil is provided only at the side wall 5 which is most likely to receive stacking pressure when the corrugated cardboard F is used as a packaging box G, thereby saving the electrolytic iron foil. Furthermore, even if the reinforcing layer 2 is limited in this way, the cardboard box generally has a part that becomes the side wall 5 continuous in the longitudinal direction, and a part that becomes the top lid 6 on one side of the cardboard box, as shown in the developed view shown in FIG. However, since the bottom cover 7 is attached to the other side, the electrolytic iron foil must be inserted into the predetermined position during the manufacturing process of the corrugated board F, or the base paper of the core 1 must be inserted in advance. By adhering electrolytic iron foil, mass production is possible without major changes to the corrugated board manufacturing process. Moreover, it is of course more suitable for reducing the weight of the box G than using electrolytic iron foil for the entire corrugated board F, and with this type, there is no risk of the electrolytic iron foil rubbing against hands when opening and closing the lids 6 and 7. By the way, electrolytic iron foil has plasticity, but if there is no electrolytic iron foil at the cut part, there is an advantage that the cut surface will not become dull. Furthermore, since the seam 8 is also reinforced, the box can be assembled robustly.

However, even if the entire surface of the cardboard is reinforced with electrolytic iron foil, it does not go against the spirit of this invention. Note that hot-melt adhesives, vinyl-based adhesives, or chloropyrene-based adhesives are suitable for adhering the electrolytic iron foil and paper.

Next, FIGS. 5 to 9 show other embodiments of this invention, which will be explained in sequence.

First, in Fig. 5, reinforcing layers 2 are placed on both sides of the paper core 1.
2 along the bend. In this case, not only the core 1 is greatly strengthened by the reinforcing layer, but also the core 1 is prevented from absorbing moisture, so there is no risk that the strength of the core will be reduced even in humid conditions. do not have.

Further, in FIG. 6, a reinforcing layer 2 is provided in the middle of the paper core 1. In other words, paper 1a is placed on both sides of the electrolytic iron foil.
It has a structure in which 1a is glued. In this case, it is preferable to apply a hot melt adhesive to the paper surface in advance, and then adhere the coated surface to the electrolytic iron foil.

With this configuration, the core 1 is of course strengthened, and since both sides of the core 1 are made of paper 1a, 1a, production can be performed using a corrugate machine, which is a general corrugated board manufacturing machine. When corrugating core base paper, the electrolytic iron foil does not come into contact with the corrugating rolls, which prevents corrugating rolls from being worn out. Also, starch glue, which is commonly used for adhering the core and liner, is used. There are advantages that can be achieved.

Furthermore, in FIG. 7, a reinforcing layer 2 is provided on the inner surface of the front liner 3. This prevents the surface from tearing due to external impact, and also prevents rainwater from entering the cardboard box F from the outside, thereby effectively strengthening the moisture and water resistance of the cardboard box. Although not shown in the figure, if a reinforcing layer is similarly provided on the back liner 4, the moisture resistance and water resistance will be further strengthened, making it especially suitable as a cardboard box for packaging items with high moisture content, such as vegetables, marine products, and marine products. It is.
Further, a simple electrolytic iron foil can be used for the liners 3 and 4, and in this case, since the electrolytic iron foil appears on the outer surface, it is preferable to enhance the cosmetic appearance by plating or the like. When electrolytic iron foil is used on the liner side in this way, it can be expected to develop new uses as a liner that can attract magnets.

Further, in FIG. 8, a reinforcing layer 2 is provided in the middle of the paper front liner 3. In this way, corrugated cardboard can be mass-produced by using a general corrugating machine as in the case shown in FIG.

Furthermore, if a reinforcing layer is similarly provided on the back liner 4, the reinforcing effect will be further increased.

In FIG. 9, the front and back liners 3 and 4 are formed to have a waterproof structure in which the reinforcing layer 2 is sandwiched between the plastic films 3a, 3a and 4a, 4a. There is no risk of corrosion and the durability is good.

FIG. 10 shows that the front and back liners 3 and 4 are made by laminating electrolytic iron foil with a heat-fusible film 8, which is adhered to the core 1 by heat-welding the film 8, and the front and back sides of the corrugated board F are bonded together. It has a reinforcing layer 2 on it. In this way, manufacturing is easy, and there is no fear that the front and back liners 3 and 4 will peel off due to water.

FIG. 11 shows a laminated structure in which the core 1 has a reinforcing layer 2 of electrolytic iron foil sandwiched between papers 9, 9, and the front and back liners 3, 4 have a structure in which a cloth 11 is laminated to a paper 10. In this way, both compressive and tensile strengths are achieved. In this case, the cloth 11 is preferably woven from a flat yarn made of a stretched film of polypropylene or polyethylene.

Although not shown in the drawings, this electrolytic iron foil can be used for the entire core and liner in the corrugated cardboard structure to make a stronger box or a box for shielding electromagnetic waves.

In addition to the above, there are many other corrugated cardboard structures that can be used, including multi-sided and multi-sided structures.
In any case, unlike rolled foil, which has elasticity, electrolytic iron foil has front and back liners 3 and 4 on the top of the core 1.
Since it does not provide enough resistance to adhere evenly, the center core 1
The front and back liners 3 and 4 are strongly adhered to each other.

As explained above, this invention skillfully utilizes the material of electrolytic iron foil to provide the corrugated cardboard structure with a reinforcing layer that is strongly bonded to the corrugated cardboard structure, so it can be used without increasing the thickness of the cardboard. Its strength can be greatly increased. In particular, the strength against pressure perpendicular to the direction of the tiers increases, so when used as a box, it easily withstands stacking pressure, is suitable for transporting and storing heavy objects, and allows boxes to be stacked high. Moreover, since it does not take up much space as a packaging material and is lightweight, products can be transported or stored advantageously. Furthermore, when disposing of this packaging material, the electrolytic iron foil is incinerated and turns into powder, leaving no trace of the foil, making post-disposal treatment very easy.

Furthermore, since the cut surface of electrolytic iron foil is not sharp,
Even if the electrolytic iron foil is exposed at the edge of the cardboard, there is no risk of injury to hands, and it is easy to work with. This solution solved all the disadvantages of the system in one fell swoop, making it much more practical.

The cardboard of this invention is strong and has an electromagnetic shielding effect, so it is suitable for use as a back plate for televisions and radios.

[Brief explanation of the drawing]

Figures 1 to 4 show one embodiment of this invention, Figure 1 is a perspective view of a packaging box using reinforced cardboard, Figure 2 is an enlarged sectional view taken along the line A-A in Figure 1,
FIG. 3 is a developed plan view of the packaging box, and FIG. 4 is a partially cutaway perspective view of the cardboard used in the packaging box. FIGS. 5 to 11 are cross-sectional views of cardboard boxes showing other embodiments of this invention. F...Cardboard, G...Box, 1... Core, 2...
...Reinforcement layer, 3...Front liner, 4...Back liner.

Claims (1)

[Claims for Utility Model Registration] 1. In a corrugated board made by adhering a liner to one or both sides of a corrugated core,
A reinforced corrugated board characterized in that a reinforcing layer made of electrolytic iron foil in which iron powder is hardened by electroforming is provided on the core or on at least one liner of the single-sided or double-sided liner. 2. The reinforced corrugated board according to claim 1, which is for use in packaging boxes and is characterized in that the reinforcing layer is provided only in the side wall portion. 3. The reinforced corrugated board according to claim 1 or 2, wherein the reinforcing layer is located in the middle of the paper core.