JPH0355425B2 - - Google Patents

Description

Detailed Description of the Invention This invention uses inorganic aggregate such as calcium carbonate powder as the main raw material, and when this aggregate is integrally coagulated with vinyl chloride resin, foamed voids are created between the aggregate composition particles. The composition particles are tightly attached to each other with a film of vinyl chloride resin, and the adhesive strength between the particles is strengthened, while at the same time minimizing the amount of resin material used. The properties of the molded plate are made to be as close as possible to those of a pure inorganic plate.

Conventional inorganic boards of this type have poor molding properties due to the use of cement, gypsum, etc. as the filler material, and it has been difficult to mold lightweight boards. Moreover, such pure inorganic boards do not have sufficient impact resistance properties, bending strength properties, etc., and furthermore, they have extremely poor construction properties such as cutting, drilling, and nailing.

In contrast, with inorganic boards that are provided by mixing resin adhesive into inorganic powder and molding, it is of course necessary to completely fill the spaces between aggregates with adhesive resin. However, a large amount of resin is inevitably used, which causes many problems when used as an inorganic board.

The method for forming an inorganic board according to the present invention was specially devised in view of the disadvantages of the conventional inorganic board. The aggregates are reliably connected using a resin film such as vinyl chloride that is attached, and the gaps other than the film part used for this connection are used as foam gaps to remove unnecessary resin material between the aggregates. It is designed to eliminate the possibility of intervening materials and to ensure the same functional effect as that of almost pure inorganic plates, as well as to reduce the weight of the plates themselves and to improve bending and impact resistance properties. It is.

To explain in detail one example of a typical manufacturing method of an inorganic board according to the present invention, it is possible to use a resin material such as vinyl chloride whose mechanical properties such as tensile strength are relatively less likely to be damaged by foaming. After adding around 20% of a solvent such as toluene and stirring it, the resin material 15
Add inorganic powder such as calcium carbonate to ~25%
Mix 75 to 85%, and further mix 6 to 8% of a blowing agent to the mixture of both materials, and after thorough kneading, fill it into a mold and heat at 150 to 170℃ for about 30 minutes. The inorganic plate was obtained by heating and foaming in the process.

The solvents used in the above are methyl alcohol, acetone, benzene, trichlene, formic acid, or tetrahydrofuran, etc., depending on the characteristics of the resin material used, and carbonic acid is used as the blowing agent. Soda, freon, propane, butane, or pentane are selectively used.

In addition, when calcium carbonate is used as the inorganic material together with such a foaming agent, it exhibits a foaming function by itself, and complete voids are formed between the particles.

The inorganic 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 continuous as a series. In addition, the gaps between the particles 1 to 1 are completely foamed voids 3.

Such a particle structure was even more noticeable when the aggregate used was calcium carbonate, and the carbon dioxide gas generated during heating caused the particle size to increase.
A gap 3 is reliably formed between 1 and 1, and the resin material is reliably pressed and bonded as a film 2 to the circumferential surface of the particle 1 by the generated carbon dioxide gas.

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 has excellent mechanical properties.

In addition, in the film structure of the particles 1, even when the particles 1 are calcium powder, it is reliably shielded from the outside, and strength deterioration due to moisture absorption etc. is reliably prevented. Together with this, it is a completely water-resistant structural board.

Furthermore, by using the foamed structure having the film 2 mentioned above, the heat insulation and sound insulation properties of the board are extremely good, and
By omitting the use of resin materials due to such a two-layer structure, the non-combustibility function is further ensured, and the generation of harmful gases etc. during heating is suppressed as much as possible.

[Brief explanation of drawings]

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

Claims (1)

[Claims] 1 Solid content dissolved in a solvent such as toluene 80
% of vinyl chloride resin material and 75-85% of inorganic powder aggregate such as calcium carbonate.
Mix 8% blowing agent and knead to 150℃~170℃/30
A method for forming an inorganic foam board characterized by heating and foaming within a range of about minutes.