JPH0379314B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a decorative coating method for inorganic building materials. Traditionally, building materials made from inorganic materials have been widely used, but these inorganic building materials have the disadvantage of being achromatic and have poor decorative properties, so they are difficult to use when used for exterior wallboards, etc. It is common practice to apply a colored coating to the However, inorganic building materials are alkaline and prone to efflorescence, and their surfaces are highly hygroscopic, which can affect the coating process and cause variations in the adhesion of the paint film. Many had the disadvantage that the coating film was likely to peel off after years of use. In view of the above-mentioned drawbacks, this invention was made with the aim of providing a decorative coating method for inorganic building materials that has good adhesion and is less likely to peel off. After treating the base surface, apply a paint with a viscosity of 20 cps or less, then immediately apply a paint of the same material as the above paint with a viscosity of 40 cps or more, let this dry, and then apply the necessary top coat. It is characterized by the fact that This invention will be explained below with reference to Examples. FIG. 1 is a conceptual diagram showing the steps when implementing the method of the present invention. The decorative coating method for inorganic building materials according to the present invention is based on an inorganic building material 1 formed by an appropriate method such as extrusion molding, paper forming method, or dry manufacturing method, and cured and cured.
After performing base surface treatment such as polishing or dust removal treatment on the surface, paint 2 with a low viscosity of 20 cps or less is applied by an appropriate means such as a flow coater, roll coater or spray, and then this paint is dried. Immediately apply a paint 3 made of the same material as the paint 2 with a predetermined viscosity of 40 cps or more (the viscosity of the paint required for normal painting), and then dry it 4. It is then constructed by applying a necessary top coat. In addition, in the case of decorative painting, when the paint 3 is used as a top coat, the top coat is not applied after the drying process. Therefore, according to the present invention, when painting the surface of the building material 1, in order to apply the paint 2 with low viscosity,
This paint quickly penetrates into the surface of the building material 1, and since the paint 3 is applied immediately before the paint 2 dries, the paint 3 easily blends into the surface of the building material 1 through the paint 2, resulting in extremely strong adhesion. can get. By the way, a 5 x 5 grid test was conducted using a conventional coating method, that is, one in which a paint with a viscosity of 40 cps was directly applied after the base surface treatment of Building Material 1, and a sample coated by the method of the present invention. The results shown in the table below were obtained, and it was found that the coating film obtained by the method of the present invention had excellent adhesion. 【table】

[Brief explanation of drawings]

FIG. 1 is a conceptual diagram showing the steps of implementing the present invention. 1... Inorganic building material, 2... (low viscosity) paint,
3... (high viscosity) paint.

Claims (1)

[Claims] 1. After applying the base surface treatment to the surface of the cured inorganic building material, apply a paint with a viscosity of 20 cps or less, then immediately apply a paint of the same material as the above paint with a viscosity of 40 cps or more, and from now on 1. A decorative coating method for inorganic building materials, which comprises drying and then applying a necessary top coat.