JPS6228116B2 - - Google Patents

Description

Detailed Description of the Invention This invention uses gypsum powder, which is stably supplied at a relatively low cost, as the main raw material, and binds the gypsum powder, which is the main raw material, more effectively to form an inorganic board. This is intended to effectively improve impact resistance, bending strength, etc.

Conventionally, this type of inorganic board has poor molding properties due to the use of cement, gypsum, etc. as the filler material, and it has been difficult to provide a lightweight board. In addition, such pure inorganic boards do not have sufficient impact resistance, bending strength, etc., and furthermore, their construction properties such as cutting, drilling, and nailing are extremely poor. .

In contrast, with inorganic boards that are provided by mixing resin adhesive into inorganic powder and molding, the spaces between aggregates are completely filled with adhesive resin. This required a large amount of resin to be used, which functioned more as a hard resin molded plate than as an inorganic plate.

The method for forming a gypsum board according to the present invention was devised especially in view of the inconveniences of the conventional inorganic boards, and uses fine gypsum powder as a forming aggregate and adheres to the surface of the aggregate. The aggregates are reliably connected with a resin film such as vinyl chloride, and the gaps other than the film part used for this connection are made into foam gaps, so that unnecessary resin material is interposed between the aggregates. This eliminates the leeway and promises the same functional effectiveness as an almost pure inorganic board, while also reducing the weight of the board itself and improving its bending and impact resistance properties.

To explain in detail one embodiment of a typical manufacturing method of a foamed gypsum board according to the present invention, a resin material such as vinyl chloride whose mechanical properties such as tensile strength are relatively unlikely to be damaged by foaming is used. 15-30%, typically
20% to 15% to 30%, ideally around 20% of a solvent such as toluene or aluma oil is added to the resin material and mixed with stirring, and the required amount of talc is mixed in according to the purpose.60 ~80%, ideally 80%, and further mix 2 to 4%, ideally 4% of a blowing agent such as azobisisobutyronitrile to the mixture of both materials, and then After kneading, the mixture is filled into a mold and heated and foamed at 150 to 180°C for about 30 minutes to obtain a foamed gypsum board.

The gypsum powder used in the above is mainly calcined gypsum or anhydrous gypsum from which H ₂ O groups have been removed as much as possible. This is what I expected.

The solvents used in the above are methyl alcohol, atocene, benzene, trichlene, formic acid, or tetrahydrofuran, etc., as appropriate, depending on the characteristics of the resin material used, and blowing agents such as azo Bisisobutyronitrile, soda carbonate, freon, propane, butane, or pentane are selectively used.

The foamed gypsum board according to the present invention has the characteristic structure described above, and the resin film 2 is reliably laminated on the surface of the particles 1 to 1 constituting the board, and this resin film 2 is formed as a series. These particles continuously exhibit a predetermined adhesive strength, and these particles 1 to 1
The gap in between is a complete foaming gap 3.

In such a foamed structure of an inorganic plate, particles 1
~ 1 are completely integrated with the coating 2, and the coating 2 forms a honeycomb-like structure, giving the plate itself unique impact resistance and bending strength characteristics, unlike conventional inorganic plates. It exhibits excellent mechanical properties.

Since the particles 1 themselves are gypsum particles, the particles adhere to each other before forming the film 2 or in the non-formed part of the film 2, and the adhesion of the particles themselves leads to reinforcement, especially mechanical properties. An improvement was observed.

In addition, in the film structure of the particles 1, since the particles 1 are reliably shielded from the outside, unlike "CaSO ₄ 2H ₂ O", moisture is not induced at all, and the strength due to moisture content is reduced. Deterioration is reliably prevented.

Furthermore, by using the foamed structure having the membrane 2 described above, the board has good heat insulation and sound insulation properties, and the resin material with such a membrane 2 structure. By omitting the above, the non-flammable function is further ensured, and the generation of harmful gases etc. during heating is suppressed as much as possible.

The foamed gypsum board according to the present invention has the characteristic functions and effects described above, and due to its unique structure, it does not require molding, thermal bonding, cutting, nailing, etc. that are not found in gypsum boards. It is specifically designed to have good construction properties and excellent heat insulation properties.

[Brief explanation of the drawing]

The accompanying drawing is an enlarged sectional view of a main part showing a typical example of a foamed gypsum board provided by the molding method according to the present invention. In the figure, 1...particles, 2...film, 3...foamed voids.

Claims (1)

[Claims] 1. 15-30% synthetic resin material such as vinyl chloride with 15-30% solvent such as toluene added, 60-80% gypsum powder mixed with talc and 2-4% blowing agent.
are mixed, kneaded, heated and foamed, and the surfaces of the gypsum powder particles 1 to 1 are covered with a film 2 of the resin material,
In addition, the film 2 is continuous and the particles 1
A method for forming a foamed gypsum board, characterized in that the space between 1 and 1 is a foamed void 3.