JPH0511068B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing an inorganic decorative board having a novel appearance.

(Prior Art and Problems to be Solved by the Invention) Conventionally, a method has been proposed for inorganic decorative boards such as ceiling panels, such as rock wool and plasterboard, by applying printing or sputtering to the surface to create a pattern with shading. However, there was a problem in that it was not easy to create patterns with rich depth and shading through printing or the like.

(Means for Solving the Problems) In view of the above-mentioned problems, the present inventors have created an inorganic foam material with a colorant absorption rate different from that of the silicic raw material in the fired body in order to obtain a decorative board with rich depth and shading. We focused on the fact that when colored together, the inorganic foam material is colored darker than the silicic material due to the difference in absorption rate, and we completed a method for manufacturing decorative boards with patterns rich in depth and shading. Ivy.

That is, the gist of the present invention is to knead a granular inorganic foam material that has been rapidly expanded in advance, a silicic raw material, and a foaming agent, and to sinter and foam the resulting kneaded product at a temperature below the melting point of the inorganic foam material. The method is characterized by: forming a fired body into a predetermined shape, grinding the surface of this fired body to expose the inorganic foam material and glassy cells on the surface, and applying a hardening colorant to the ground surface. There is a method for manufacturing an inorganic decorative board.

As the granular inorganic foam material, inorganic powder and granules such as pearlite, rosinite, obsidian, or shirasu are used.
Spherical bodies obtained by rapidly heating at 900 to 1,200° C. within a few minutes and expanding several to tens of times are used, such as commercially available pearlite, shirasu foam, and fuyorite made by expanding obsidian. In general, the inorganic foam material used has a diameter of 1 mm to several mm, but a diameter of 2 mm to 5 mm is preferred. Note that this inorganic foam material has many fine cells with a wall thickness of several tens of microns or less in diameter, so it is more fragile than fired silicic acid raw materials, but it has the property of having a high colorant absorption rate. There is.

The siliceous raw material is one containing 60% or more of SiO ₂ , and for example, siliceous viscosity such as acid clay and frog's eye clay are used.

As the blowing agent, soda ash, sodium nitrate, calcium carbonate, zinc oxide, sodium silicate, dolomite, etc. are used.

The kneaded material basically consists of several weight percent to several tens of weight percent of the granular inorganic foaming material, 50 weight percent to 80 weight percent of the silicic acid raw material, and 5 weight percent to 30 weight percent of the blowing agent.
In addition, in order to improve kneadability, dispersibility, and affinity, flocculants and thickeners from 0.1% to 10% by weight are added as necessary.
% by weight may be added. And the said component is
Usually, 5% to 15% by weight of water is added to the mixture and kneaded.

As the flocculant, for example, aluminum phosphate is used, and as the thickener, for example, polyvinyl alcohol (PVA), carboxymethyl cellulose (CMC), etc. are used.

As for the kneading method, the above components are mixed in an appropriate order and kneaded.

Depending on the viscosity of the kneaded product obtained by kneading,
For example, if it is clay-like, it may be rolled with rollers and formed into a plate shape, or if it is paste-like,
You can also mold it into the butt.

Firing and foaming is carried out by heating the kneaded material at a temperature below the melting point of the inorganic foam material (700 to 1000° C.) for several tens of minutes to several hours. By this operation
Glassy cell with a diameter of 0.1 to several millimeters (hole 1)
A fired body with a specific gravity of 0.2 to 0.2 is obtained.
It is about 0.5.

Next, the surface of the fired body is ground to expose the pores 1 formed by the foaming agent and the cells of the inorganic foamed material 2, as shown in the figure, and to flatten the surface of the fired body. Grinding methods include sandblasting, shotblasting,
The pores 1 and the inorganic foam material 2 are exposed by brushing, a cutter, a router, a grinder, or the like. Incidentally, 3 indicates that cracks appear in the non-foamed melted portion of the silicate raw material.

The coloring agent applied to the ground surface of the fired body is
A curable type is used in which an organic binder such as acrylic, urethane, or epoxy, or an inorganic binder such as water glass or metal alkoxide is mixed with an appropriate pigment or dye for coloring.

By applying and permeating the hardening type colorant, the fragile cells of the inorganic foam material can be reinforced at the same time as coloring, and dust that is not completely removed during grinding can be fixed.

Known methods such as spraying are used to apply the colorant, but when applying by spraying, it is not enough to finish the application in one go, but it is divided into multiple applications and applied in different directions. It is preferable to do this in order to coat the inside of the cavity 1. As a result, the colorant soaks into the fragile, microscopic cells of the exposed inorganic foam and settles, creating a deep color, strengthening it, and generating less dust during transportation, installation, and use.

On the other hand, since the pores 1, which are glassy cells, hardly absorb any colorant, the dust that remains in the recesses and cannot be completely removed during grinding is fixed.
This has the advantage of reducing the amount of dust floating during use.

(Example) 10 parts by weight of pearlite with a diameter of 2 to 5 mm was used as a granular inorganic foam material, and acid clay was used as a silicate raw material.
68 parts by weight, 13.5 parts by weight of sodium carbonate and sodium abate as blowing agents, and 0.5 parts of PVA as a flocculant.
A mixture of 8 parts by weight and 8 parts by weight of water was kneaded, and the resulting kneaded product was rolled with rollers to form a plate, which was preheated at a maximum temperature of 850°C and heated for 120°C including slow cooling. After firing and foaming for a minute to form a fired body, the surface of this fired body is flattened with a grinder, and then a coloring agent with acrylic resin as a binder is sprayed on the ground surface of the fired body in multiple steps from different directions. A sample was obtained by coloring.

When the surface pattern of the sample was visually observed, it was found that the coloring agent soaked into the exposed inorganic foam material, and the inorganic foam material 2 was colored more deeply than the primary color of the colorant, while the voids 1 were formed. It was found that the grains were colored with almost the same hue and brightness as the primary color of the coloring agent, and that there was a difference in brightness between the two. Then, the exposed void portion 1 and non-foamed melted portion 3 are exposed.
It was found that the shading caused by the unevenness gives depth to the surface pattern of the fired product, and a new pattern that cannot be obtained by printing etc. can be obtained.

(Operations and Effects of the Invention) As is clear from the above explanation, according to the method of the present invention, after firing and foaming, the surface of the fired body is ground, and a hardening colorant is applied to the surface where the inorganic foam material is exposed. As a result, the coloring agent penetrates into the fine cells of several tens of microns or less inside the inorganic foam material by capillary flow, and the inorganic foam material is colored deeper than the primary color of the colorant, and the weak and thin cells are reinforced. Therefore, dust is less likely to be generated during transportation, construction, and use.

On the other hand, even if the coloring agent adheres to the grains of the glassy cells that form the pores, it hardly penetrates and accumulates inside the cells, resulting in a hue that is almost the same as the primary color of the colorant.
Fixes dust that is brightly colored and cannot be removed during grinding.

Therefore, the difference in brightness between the two becomes clear, and together with the shading caused by the unevenness of the voids and non-foamed fused areas, a decorative board with a deep and rich surface pattern is obtained, and the generation of dust is prevented. There is an effect that it can be done.

[Brief explanation of the drawing]

The figure is a partially enlarged sectional view of a decorative board showing one embodiment of the present invention. 1... Glassy cells (holes), 2... Inorganic foam material.

Claims (1)

[Claims] 1. Knead a granular inorganic foam material, a silicate raw material, and a foam material, and fire and foam the obtained kneaded product at a temperature below the melting point of the inorganic foam material to form a fired body of a predetermined shape. 1. A method for producing an inorganic decorative board, which comprises: grinding to expose the inorganic foam material and glassy cells on the surface, and applying a hardening colorant to the ground surface.