JPH01164476A - Method for manufacturing inorganic decorative board with unevenness - Google Patents

Abstract

PURPOSE:To improve the durability and decorative property of a decorative sheet by coating the surface of an underlayer of synthetic resin formed on the embossed surface of an inorg. base material with inorg. paint contg. a specified metal alkoxide and by curing the paint. CONSTITUTION:The embossed surface of an inorg. base material is coated with a synthetic resin soln. and an underlayer is formed by curing. The surface of the underlayer is coated with inorg. paint contg. a metal alkoxide represented by a formula M(OR)n (where M is Si, Ti, Al, Zr, Sr, Ba, Pb, Sn, La, Na or Fe, R is 1-10C alkyl and n is an integer of 1-4) as a binder and the paint is cured to form a paint film as a surface layer. Thus, an inorg. decorative sheet having ruggedness is produced.

Description

[Detailed Description of the Invention] Detailed Description of Sangyo-L The present invention is a method for manufacturing an inorganic decorative board that has excellent coating performance in terms of durability, maintains a good appearance for a long period of time, and eliminates unevenness. No matter what.

Conventional techniques and their problems Conventionally, as inorganic decorative boards for smoothing unevenness, calcium silicate temporary, slag gypsum temporary, and pulp cement temporary were used.

Some products, such as asbestos slate, are made by mixing inorganic grains with fibrous reinforcing materials, press-molding the surface, and then applying paint to the surface to form a coating film. .

However, when the press molding process is applied to the inorganic decorative board, the structure of the convex portion becomes a river, and the fibrous HLI reinforcement material is exposed on the surface of the convex portion, causing fuzz. When paint is applied to the surface of the convex part, the convex part absorbs a large amount of paint from the four parts and the flat part, making it difficult to form viv4. For this reason, when applying a large amount of paint, it accumulates in the four parts, causing problems such as foaming.
Applying the paint of i) - When a paint film is formed, the paint film is likely to peel off or change color.In particular, top coat paints such as synthetic resins are easily decomposed by ultraviolet rays and ripening, resulting in significant deterioration of cosmetic properties. Ta.

For this purpose, an inorganic paint with excellent heat resistance, weather resistance, chemical resistance, and scratch resistance, such as the one described in JP-A-50-54620, is applied and cured on the surface of the inorganic base material to form a top coat. He is trying to maintain durability through his own performance.

However, the above-mentioned inorganic paint is only cured by its own curing reaction, and its adhesion to the base material and the undercoat is insufficient. Although it is necessary to heat at a higher temperature than above, since the inorganic base material has a high specific heat, only the convex portions become hot and the concave portions are difficult to heat up.

Therefore, a large temperature difference occurs between the convex portions and the concave portions, making it difficult to uniformly heat and harden the inorganic paint.

As a result, the solvent may scatter before the curing reaction occurs at the convex portions, resulting in poor curing, or internal stress may occur in the coating film, which may easily cause peeling or cracking. and inorganic groups (e) were susceptible to thermal deterioration.

Therefore, in the conventional method for manufacturing an inorganic decorative board, it is difficult to obtain an inorganic decorative board with no unevenness that is excellent in durability and maintains good cosmetic properties for a long period of time.

Prior to the present invention, in view of the above-mentioned problems, surface coatings were developed that interrelated good surface properties between an inorganic base material whose surface was subjected to a pressure molding process and an undercoat film. As a result, we have completed a method for manufacturing an inorganic decorative board with unevenness that is excellent in durability and cosmetic properties.

That is, the gist of the present invention is to apply a synthetic resin liquid to an inorganic base material whose surface has been subjected to a pressure molding process and cure it to form an undercoat film. ) (In the formula, M is silicon, titanium, aluminum, zirconium, strontium, barium, lead, tin, lanthanum, sodium or iron, R is an alkyl group having a carbon number of 1 to 10, and n is an integer of 1 to 4. ) A method for producing an inorganic decorative board having irregularities is characterized by applying a soot metal alkoxide-based inorganic paint using a metal alkoxide represented by the following as a binder and curing it to form a surface coating film.

Examples of the inorganic base material include calcium silicate board 2 asbestos cement calcium silicate board 1 asbestos slate slab gypsum board, pulp cement board, and ALC.

Examples of the press molding process include a method of forming uneven portions on the surface of the inorganic base material using a roll press, a planographic press, etc. before the inorganic base material is cured.

Examples of the synthetic resin liquid include epoxy resins, urethane resins, acrylic resins, and unsaturated polyurethane resins.

As a method for applying the synthetic resin liquid, any method such as spraying, application using a sbonno roll, or brushing roll can be adopted.

The amount of the synthetic resin liquid to be applied depends on the condition of the uneven parts, and the thickness of the undercoat film is 2μ in terms of flat surface so that it does not accumulate on the four parts.
The amount is preferably from m to 100 μm.

The metal alkoxide-based inorganic paint is a transparent resin paint composed of a metal alkoxide F body represented by the above-mentioned general formula (%), and titanium oxide, if necessary.

It is a colored paint that is colored by appropriately mixing pigments such as iron oxide, clay, red lead, and alkaline oxide.

The metal alkali; 1-kind inorganic paint can be applied by any method similar to the method for applying the synthetic resin liquid described above, but since the surface to be coated has uneven parts, the application process may be repeated multiple times. It is preferable to apply and dry the coating separately in order to prevent discoloration and efflorescence of the coating film.

The amount of the metal alkoxide-based inorganic paint to be applied is preferably such that the thickness of the paint film is 2 μm to 1100 B in terms of a flat surface, depending on the state of the unevenness, so as not to accumulate on the four parts.

Next, the manufacturing process will be explained.

When pressure molding is applied to an inorganic base material, the structure of the convex parts, which is made up of binders such as cement and fillers such as wood flour, perlite, and silica sand, becomes slightly coarser than that of concave parts, and the structure of the convex parts is made up of binders such as cement and fillers such as wood flour, perlite, and silica sand. The material, such as asbestos, polypropylene, pulp, etc., is exposed from the surface of the convex part due to the sliding phenomenon, and the surface of the convex part becomes fluffy.

When a synthetic resin liquid is applied to the surface of such an inorganic base material, the synthetic resin liquid is not absorbed as much in the concave parts as compared to the convex parts and tends to accumulate. The surface of the convex portion is covered with an extremely thin undercoat film because the fluff is sucked in or repelled by the fluff.

Next, when a metal alkoxide-based inorganic paint is applied on top of it, the undercoat film made of synthetic resin liquid cannot completely prevent the suction of the inorganic paint at the convex parts, so the alkali component of the inorganic base material is slightly removed at the convex parts. It oozes out and becomes weakly alkaline (below PHII), which activates the curing reaction of the metal alkoxide paint shown below.

The synthetic resin layer was provided because without the synthetic resin layer, the coated surface of the inorganic base material would become strongly alkaline (about PI-II 4), and the metal alkoxide-based inorganic paint would be hydrolyzed.
This is because it is difficult to undergo a polycondensation reaction, resulting in poor curing.

The metal alkoxide-based inorganic paint is usually heated at room temperature to 180°C, preferably at 70°C under a catalyst such as ammonia.
It is cured at a heating temperature of .degree. C. to 150.degree. C., at which time hydrolysis occurs, and it is cured by the polycondensation reaction shown below.

M(01υn+nllyo-M(OII)n+nR(O
II) M(Orl)n→MOn/2 + n/Jl 2
0 Since the convex portion cannot completely prevent suction, when a metal alkoxide-based inorganic paint is applied, the weak alkaline component of the inorganic base material oozes into the metal alkoxide paint due to the suction effect of the alcohol, which is the solvent. come. Since this weak alkaline component functions as a catalyst for the above-mentioned polycondensation reaction, the curing reaction is accelerated.

This improves adhesion around the convex parts, making it difficult for the paint film to peel or crack around the convex parts as in conventional examples.
The durability of the coating film is improved.

Furthermore, even after the curing reaction of the metal alkoxide-based inorganic paint is completed, a trace amount of M-
It is thought that 011 and Ca(OH) emitted from the inorganic base material at t2 form an ether bond to form M-0-Ca-〇-M, which further improves the strength of the coating film.

Example I Pressure molding is performed on the surface to a depth of 0, I mm to 3 mm.
After applying Epoquin resin liquid to a cement calcium silicate board with a specific gravity of 1.5 and having many uneven parts formed thereon so as to have an average thickness of 30 μm in terms of a non-absorbing board on the back side, and curing to form an undercoat film. A metal alkoxide-based white paint, which is a mixture of a silicon alkogide main liquid and an ammonia-based auxiliary liquid, is applied so that the average 17 is 30 μm based on the case where it is applied to a flat non-absorbing plate. and set this to temperature 1
The sample was obtained by heating at 20° C. for 20 minutes to harden it.

Comparative example! In place of the non-alcokind white paint in Example 1, a water-soluble alkali silicate-based inorganic paint was applied in the same amount as in Example 1, and it was cured by heating at a temperature of 200'C for 30 minutes. The sample was obtained by carrying out the same operation as in Example I described above except for the following.

Observe the valley sample obtained as described in Ii.

The experimental results are shown in Table 1.

Table 1 *Aesthetics The results of visual observation of the surface are shown.

*Water Resistance Shows the results of visual observation of the surface shape after being immersed in water for 30 hours.

* Shows the results of visual observation of the surface after being heated by placing it on a pot plate with a heat resistance temperature of 200°C for 15 minutes.

As is clear from the above results, in Example I, fluff 1
Since no foaming or warping occurred, the aesthetic appearance of Example 1 was better than that of Comparative Example 1.

In addition, in the water resistance and heat resistance tests, there was no cracking or peeling of the coating on the uneven parts of Example 1, and the surface was not discolored, so Example 1 was better than Comparative Example 1.
It was found that the water resistance and heat resistance were superior to that of the

As is clear from the explanation beyond the series, according to the present invention, when a metal alkoxide-based inorganic paint is applied to the surface of an inorganic base material with unevenness via a synthetic resin, weakly alkaline soil of the inorganic base material is removed from the convex portions. It seeps into the metal alkoxide paint, and the alkali component acts as a catalyst, promoting the curing reaction.

Further, since the functional groups of I'i1 remaining after the reaction are ether-bonded with the weak alkaline components exuding from the inorganic base material, the strength of the coating film is further improved.

Therefore, the paint should be applied so that it does not accumulate on the four parts.
The curing reaction strengthens the convex portions and maintains aesthetic appeal for a long time.

In addition, since the surface coating film is formed from a metal alkoxide-based inorganic paint that cures at a lower temperature than conventional inorganic paints, there is no large temperature difference between the convex parts and the four parts, and the deterioration of the base material is prevented. few.

As a result, the metal alcoquid inorganic paint is heated almost uniformly, making it difficult for internal stress to develop in the surface coating film.
The paint film is less likely to peel or crack, and the entire inorganic decorative board is less likely to warp.

Therefore, according to the present invention, it is possible to obtain an inorganic decorative board that has excellent durability and can maintain good cosmetic properties for a long time.

Claims (1)

[Claims] (1) After applying a synthetic resin liquid to an inorganic base material whose surface has been subjected to pressure molding processing and curing to form an undercoat film, the general formula: M(OR)_n (formula (M is silicon, titanium, aluminum, zirconium, strontium, barium, lead, tin, lanthanum, sodium or iron, R is an alkyl group having a carbon number of 1 to 10, and n is an integer of 1 to 4.) 1. A method for producing an inorganic decorative board having irregularities, the method comprising applying a metal alkoxide-based inorganic paint using a metal alkoxide as a binder and curing it to form a surface coating film.