JPS5838107B2 - Method for producing foamed gypsum-metal composite material - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a method for producing a foamed gypsum-metal composite material, and in particular, during production, the foamed gypsum formed on a metal plate is prevented from peeling, cracking, or breaking. The present invention relates to a method for manufacturing the composite material.

Gypsum is a noncombustible material that is widely used in construction materials.

When using gypsum as a construction material, it is necessary to reduce the weight of the gypsum by foaming or other means and to improve its insulation properties.Also, from the viewpoint of handling, current gypsum boards are too heavy, so it is necessary to make them lighter. It is hoped that this will become a reality.

However, as the bulk specific gravity of gypsum is reduced, the insulation properties of the gypsum board improve, but the mechanical strength decreases, making it more likely to break due to impact, bending, or compression.

For this reason, gypsum board, which has been made lighter by foaming or other means, has the disadvantage that it is difficult to use alone as a construction material, and to compensate for this disadvantage, it must be combined with stronger metal plates or the like.

The composite is manufactured by adhesively bonding preformed lightweight foamed gypsum board to a metal plate;
There is a method in which foamable gypsum slurry is poured onto a metal plate and allowed to harden and dry.

However, in the former method, as mentioned above, the lightweight gypsum board has low mechanical strength, so the gypsum board has the disadvantage of being easily damaged, such as chipping or bending, during the pasting process. There are many restrictions on the use of gypsum board that has been reduced in weight in advance.

In addition, the latter method has a disadvantage that the adhesive force between the metal plate and the foamed gypsum formed from the foamable gypsum slurry is weak, and it easily peels off.

In order to improve this problem of peeling, some methods have been used in which adhesive is applied to the metal plate in advance and foamed gypsum slurry is poured over it, but some improvement in adhesion has been observed. However, the adhesion is still insufficient and it is easy to peel off.

In particular, it is difficult to handle in an undried state because adhesive strength has not been developed.

Although these problems exist, the manufacturing method of composite materials by pouring foamable gypsum slurry involves pouring and molding, so it is possible to obtain products with more complex shapes and structures than the former bonding force method. There is a strong demand for a solution to the above-mentioned problems because it is advantageous in terms of weight reduction.

As a result of intensive research to solve the conventional problems mentioned above, this invention was developed by laminating a porous sheet on a metal plate in advance.
It has been discovered that by pouring a foamable gypsum slurry onto this sheet and allowing it to harden and dry, the above-mentioned problem of the foamed gypsum easily peeling off from the metal plate can be greatly improved.

In the method for producing a foam-containing gypsum-metal composite material of the present invention, since the porous sheet is laminated to the metal plate in advance, the strength of these sheets is sufficiently developed, and the porous sheet is bonded to the metal plate in advance. Since the foamable gypsum slurry is poured onto the sheet, the slurry penetrates into the porous sheet and hardens, so that the adhesive strength between the two is sufficiently developed even in a somewhat undried state. In this state, even greater adhesive strength can be obtained.

Therefore, the composite material obtained by the manufacturing method of the present invention does not easily peel off, crack, or break even when the foamed gypsum part is subjected to impact, bending, compression, etc. Therefore, by using this as a surface material, it can be easily attached to structural members of a building, and the composite materials according to the present invention can be easily attached to each other.

Examples of the porous sheet in this invention include paper,
Any suitable material can be used as long as the foamable gypsum slurry can penetrate into its porous structure and harden, such as non-woven fabric, asbestos fabric, glass wool fabric, wire mesh, polystyrene foam, polyurethane foam, etc. .

Further, as the metal plate in the present invention, any metal plate that is generally used as a building material such as aluminum, iron, copper, etc. can be used, and the thickness of the metal plate is 0.2 to 0.2 mm in the case of an iron plate. 5 mm is usually used.

In the present invention, any surface processing and surface coating of the metal plate can be used without causing any problems by appropriately selecting and using an adhesive.

The lamination of the metal plate and the porous sheet according to the present invention may be performed using any adhesive that is normally used for this type of bonding, such as an inexpensive and easy-to-handle emulsion such as polyvinyl acetate adhesive. It is possible to use a type of adhesive.

Furthermore, in the preparation of the foamable gypsum slurry in this invention, a method of generating gas using a chemical reaction, a method of mixing bubbles by adding a surfactant and stirring, and a method of mixing a lightweight aggregate with air bubbles. It may be prepared by applying any method such as the method of

The effect of this invention does not depend on the strength of the foamed gypsum itself, so any kind of foamed gypsum may be used. However, if the strength of the foamed gypsum is weak, the adhesive interface will not Destruction of the foam plaster itself may impair the apparent effectiveness of this invention.

Therefore, the stronger the strength of the foamed gypsum used in this invention, the better.

Various methods have been tried to strengthen gypsum, such as impregnating it with resin, reinforcing it with fibers, and mixing inorganic substances such as slag, and some methods have gained popularity. In most cases, the specific gravity of the gypsum increases, and many of them are unsuitable for cases where light weight is required, such as in the present invention.

In the case of foam-containing gypsum, the strength of the foam-containing gypsum is greatly reduced as the weight is reduced, so reinforcement is extremely difficult. A foamable gypsum slurry containing 10 parts by weight of glass fibers and 1 to 10 parts by weight of glass fibers with a fiber length of 5 to 30 mm is especially effective when used with a foamable gypsum slurry made of polyvinyl alcohol with a saponification degree of 95% or more. It is possible to obtain a gypsum body with remarkable foam content.

Note that glass fibers whose surfaces are untreated or treated with silane exhibit excellent reinforcing effects because the glass fibers have good dispersibility in the gypsum slurry.

In this invention, by using the foamable gypsum slurry with the above-mentioned composition, the bulk specific gravity is 0.2 to 0. 7? /cfl
A foam-containing gypsum-metal composite panel with sufficient strength can be obtained even with a foamed gypsum-metal composite panel.

Next, embodiments of the invention will be described.

Example 1 As shown in the figure, the thickness is 0. 2. Apply polyvinyl acetate adhesive 2 on a commercially available colored iron plate 1 of 27 mm. /rrj thickness and apply 200' on top of this. The paperboard 3 having a thickness of /m was laminated by roll pressing.

100 parts by weight of β-type hemihydrate gypsum and 100 parts by weight of water were placed on the paperboard 3.
Parts by weight, surfactant combination or alcohol ethoxysulfate soda salt (product name: Daiichi Kogyo Seiyaku ■) Itenol 3
25D) A foamable gypsum slurry made by stirring and foaming 0.05 parts by weight with a mixer is poured in, and this is lightly pressurized with a roll press, and after forming, it is hardened and dried to form a foamed gypsum layer 4. A composite panel was obtained.

Example 2 Polyvinyl acetate adhesive was applied to a thickness of 501/rn' on a commercially available color iron plate with a thickness of 0.27 mrtt, and a polystyrene foam sheet with a foaming rate of 30 times sliced to a thickness of 1 nm was lightly placed on top of this. It was attached by roll pressing.

Thereafter, a composite panel was obtained in the same manner as in Example 1 described above.

Example 3 A urethane mixture was sprayed onto a colored iron plate similar to those in Examples 1 and 2 to form a urethane foam layer with a thickness of 0.5 to 1.0 mm, and the layer of Example 1 described above was formed on this layer. The foamable gypsum slurry used in step 1 was poured into the mold, and the composite panel was molded and cured.

Example 4 Paperboard was laminated to a colored iron plate in the same manner as in Example 1, and 100 parts by weight of β-type hemihydrate gypsum, 100 parts by weight of water, and 0.05 parts by weight of the same surfactant as in Example 1 were added to the paperboard. In addition, 9 parts by weight of polyvinyl alcohol and 13 mr fiber length
Add 3 parts by weight of glass fibers whose surface has been treated with vinyl silane at RT, stir and foam with a mixer, pour in foamable gypsum slurry, lightly pressurize this with a roll press, and after molding, harden and dry. The foam gypsum layer was shaped to obtain a composite panel.

Comparative Example 1 In Example 1, paperboard was laminated to the colored iron plate, but this was omitted and the same foamable gypsum slurry as in Example 1 was directly poured onto the colored iron plate and molded and hardened to form a composite panel. Obtained.

Comparative Example 2 Apply 100% polyvinyl acetate adhesive to a colored iron plate. / m
"A foamable gypsum slurry similar to that in Example 1 was directly poured onto the slurry to a certain thickness, and the slurry was molded and cured to obtain a composite panel.

Comparative Example 3 A rubber adhesive was applied to a color iron plate to a thickness of IOOP/m'', and the rest was carried out in the same manner as in Comparative Example 2 to obtain a composite panel.

The undried state and dry state of the composite panels obtained in Examples 1 to 4 and Comparative Examples 1 to 3 were determined by the presence or absence of peeling,
The following table also shows the bending compressive strength when pressure is applied from the surface of the metal plate and the peel strength when a 1kg iron ball is dropped onto the metal plate from a height of 1.5 m.

As is clear from the above table, the composite panel obtained by the manufacturing method according to the embodiment of the present invention, in which a porous sheet is laminated to a metal plate, has good adhesion in both the dry and undried state. It was confirmed that the composite panels of comparative examples in which only the metal plate or only the adhesive was applied to the metal plate did not have sufficient adhesion even in a dry state, and that almost no adhesive strength could be expected in an undried state.

It was also confirmed that by bonding a porous sheet to a metal plate, both bending strength and impact strength were increased.

As explained above, according to the manufacturing method of the present invention, a metal plate and foam-containing gypsum are bonded together via a porous sheet, so that a composite panel with strong adhesive strength and high strength can be obtained. .

[Brief explanation of the drawing]

FIG. 3 is a sectional view showing a composite panel obtained according to an embodiment of the present invention. 1... Iron plate, 2... Adhesive, 3...
... Paperboard, 4... Foamed gypsum layer.

Claims (1)

[Claims] 1. In manufacturing a composite material of foamed gypsum and metal plate, a porous sheet is laminated to the metal plate in advance, and foamable gypsum slurry is poured onto this sheet and hardened and dried. A method for producing a foam-containing gypsum-metal composite material, characterized by: 2 100 parts by weight of calcined gypsum, 2 to 1 parts of polyvinyl alcohol
0 parts by weight and 1 to 1 glass fibers with a fiber length of 5 to 30 mm
The method for producing a metal composite under foamed gypsum according to claim 1, characterized in that a foamed gypsum slurry containing 0 parts by weight is used.