JPH0144502B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a heat insulating panel.

BACKGROUND ART Conventionally, a heat insulating panel is known that is made by injecting a foamable urethane resin raw material into the middle of metal plates facing each other and foam-molding the material. This conventional insulation panel using urethane foam is mainly used in commercial refrigerators and freezers, but it has poor heat resistance and flame resistance, and is smoke-emitting.
The panel warps when exposed to high temperatures, making it unsuitable for applications such as wall materials for refrigerated and frozen warehouses, architectural interior materials, or wall materials for automobile painting booths that are used at high temperatures. .

Therefore, phenol foam, which has good heat resistance and flame resistance, was used instead of urethane foam, but in the past, a slab of phenol foam was made in advance, and metal plates were attached to both sides of this slab with an adhesive. Insulating panels were manufactured by joining. However, with this method, the manufacturing of the heat insulating panel is extremely troublesome and time consuming, and the phenol foam is extremely brittle and has a problem of low bending strength. In addition, after pasting an inorganic board such as Setsuko board on the opposing surface of the metal plate, a slab of phenol foam is pasted to these, or a phenol resin raw material is injected between the metal plates with the inorganic board and foam molding is performed. However, since the surface layer of phenol foam becomes powdery and easily peels off, the adhesive strength is weak, and therefore the insulation panel cannot have sufficient strength. In addition, there was a problem in that the weight of the panel was increased, and since the inorganic board had poor heat insulation performance compared to phenol foam, the thickness of the panel had to be increased. Furthermore, it is also possible to manufacture heat insulating panels by injecting a foamable phenolic resin raw material into the middle of metal plates arranged facing each other and foaming the material. The resulting water prevents the bonding between the phenolic resin and the metal plate.
With this method, it has not been possible to produce an integrated heat insulating panel with sufficiently high strength.

This invention has been made to solve the above problems, and its configuration will be explained below based on embodiments shown in the drawings.

In the drawings, reference numeral 1 indicates a heat insulating panel according to the present invention, and reference numeral 2 indicates a pair of metal plates constituting the front and back surfaces of the panel, and these plates are made of an aluminum plate, a stainless steel plate, a vinyl chloride resin-coated steel plate, or the like. Bent edges 2a are provided on both left and right edges of the metal plate 2, which are bent inward into a substantially L shape. Reference numeral 3 denotes a water-absorbing sheet made of kraft paper pasted on the opposing surfaces of these metal plates 2, and 4 and 5 denote a pair of frame members made of vinyl chloride resin placed on the left and right edges of the heat insulating panel 1. Of these, the left frame member 4 is provided with a fitting recess 6, and the right frame member 5 is provided with a fitting protrusion 7. Reference numeral 8 denotes a heat insulating material made of foamed phenol resin that is filled between the metal plates 1 by injection foam molding, and a reinforcing material 9 is included in the heat insulating material 8. Here, as the reinforcing material 9, glass powder, glass fiber chips, carbon fibers, glass balloons, phenol balloons, glass balloons, etc. are used. Since glass powder is alkaline, it can neutralize the acidity of phenol foam and prevent corrosion of the metal plate. Furthermore, since the balloon is hollow, it can absorb water generated during the curing reaction of the phenolic resin.

By including such a reinforcing material 9, the heat insulating material 8
The strength of increases. In addition, the heat insulating material 8 is joined to the water absorbent sheet 3 during foam molding of phenolic resin, so the metal plates 2 on both the front and back sides of the heat insulating panel 1 and the internal heat insulating material 8 are connected via the water absorbent sheet. are integrally connected to each other.

In order to manufacture the above-mentioned heat insulating panel 1, a water absorbent sheet 3 made of kraft paper is pasted on each side of a pair of front and back metal plates 2, and these metal plates 2 with water absorbent sheets are arranged facing each other, and the left and right sides are Frame members 4 and 5 are placed on both side edges. Next, a reinforcing material 9 such as glass powder is placed between these metal plates 2.
A liquid raw material of foamable phenolic resin (resol type) containing the following ingredients is injected and foam molded. During this molding, water is generated due to the reaction of the phenolic resin, but at the interface between the water-absorbent sheet 3 made of kraft paper and the phenol resin raw material, the water is absorbed into the water-absorbent sheet 3 and removed, causing the phenol resin to harden. By doing so, the water absorbent sheet 3 and the heat insulating material 8 made of phenolic resin can be firmly bonded, and the heat insulating panel 1 can thereby be integrally molded. Since the heat insulating material 8 includes a reinforcing material 9 such as glass powder, its strength is greatly increased. Injection foam molding of phenolic resins can be carried out in batch mode or in continuous mode.

In addition, in the above embodiment, the water absorbent sheet 3
Although kraft paper is used as the paper, other papers may also be used. It is also possible to use cloth such as cotton or linen, or a water-absorbing laminate made by laminating paper and synthetic resin film or fiber.

Moreover, instead of such a water-absorbing sheet 3, a moisture-curable urethane adhesive may be applied to the facing surface of the metal plate 2. That is, a urethane adhesive 3 is applied to each opposing surface of a pair of metal plates 2 that are arranged opposite to each other, and a phenolic resin raw material containing a reinforcing agent 9 is injected into the intermediate part between these metal plates 2. When foam molding is performed, the adhesive 3 is cured by the reaction between the water generated during the curing reaction of the phenolic resin and the urethane adhesive 3, and the foamed phenolic resin containing both metal plates 2 and reinforcing material 9 is cured. The heat insulating material 8 and the heat insulating material 8 are integrally joined via the urethane adhesive 3.

In addition, when using a balloon such as a Shirasu balloon as the reinforcing material 9, since it is hollow and has water absorbing properties, it can absorb water generated during the curing reaction of the phenolic resin. There is no need to attach the water absorbent sheet 3 as described above to the metal plate 2 or apply a urethane adhesive. However, it is necessary to provide any one of these water-absorbing sheets, moisture-curing urethane resin, and shirasu balloons between the opposing metal plates 2.

The above heat insulating panels have very high strength and very low smoke generation, so they can be used as wall materials for refrigerated and frozen warehouses, architectural interior materials, shutters, doors, partitions, etc., and are heat resistant and flame resistant. It has excellent dimensional accuracy, does not warp even at high temperatures, and can be used, for example, in automotive paint booths, wood drying warehouses, food smoking rooms, constant temperature rooms (clean rooms), etc. be.

As mentioned above, the heat insulation panel according to the present invention has the following features:
A foamable phenolic resin raw material containing a dispersed reinforcing material 9 is injected into the middle part of a pair of metal plates 2 which are arranged facing each other at a predetermined distance from each other, and a water-absorbing substance 3 is made to exist. In this state, the phenolic resin raw material is foam-molded, and the moisture generated during the curing reaction of the phenolic resin is absorbed by the water-absorbing substance 3, and the heat insulating material 8 made of the foamed phenolic resin including the reinforcing material 9 after curing is formed. and both metal plates 2
The insulation panel 1 has extremely high strength, has excellent heat resistance and flame resistance, and does not warp even at high temperatures. Since it has low smoke generation, it can be effectively used in various applications such as refrigerated and frozen warehouses, architectural interior materials, and automobile painting booths. Since the heat insulating panel 1 can be made by injection foam molding the phenolic resin containing the reinforcing material 9, the manufacturing operation is very simple.

[Brief explanation of drawings]

The drawings show an embodiment of the invention, and FIG. 1 is a partially cutaway perspective view, and FIG. 2 is a partially enlarged sectional view. 1... Heat insulation panel, 2... Metal plate, 3... Water-absorbing sheet (water-absorbing substance), 4, 5... Frame material, 8...
...Foamed phenolic resin insulation material, 9...Reinforcement material.

Claims (1)

[Claims] 1 A foamable phenolic resin raw material containing a dispersed reinforcing material 9 is injected into the middle part of a pair of metal plates 2 which are arranged facing each other at a predetermined distance from each other, and a water-absorbing substance 3 is present. In this state, the phenolic resin raw material is foam-molded, and the moisture generated during the curing reaction of the phenolic resin is absorbed by the water-absorbing substance 3, and the heat insulating material made of the foamed phenolic resin including the reinforcing material 9 after curing is formed. 8 and both metal plates 2 are integrally combined.