SU977439A1 - Method for preparing surface of construction products - Google Patents

Description

(54) METHOD FOR PREPARING THE BUILDING SURFACE

PRODUCTS

one

The invention relates to the production of polymer coatings formed on solids, in particular such porous materials as concrete, silicate brick, clay brick, etc., when used as facing materials in construction.

The known method of preparing the surface of building products by treating their surface with various organic solvents 1.

However, the method is ineffective, extremely specific and requires the consumption of scarce and expensive organic solvents.

. The closest to the present invention is the method of preparing the surface of building products for applying polymer powder coatings by forming a primer sublayer by preheating the surface of a building product to 400-1200 ° C for 1-10 minutes and cooling to the film-forming temperature of the polymer coating. When heated on the surface

chemically active compounds are formed, which enhance the adhesion of the coating to the product and prevent the coating film from discharging 2.

The disadvantage of this method is the high energy consumption for heating.

The purpose of the invention is to increase the service life of the coating.

This goal is achieved by the fact that according to the method of preparing the surface of building products for applying polymer powder coatings by forming a primer underlayer, the latter is formed by layering 10-15% aqueous solution of solid sludges of aluminum production layered, while the first layer is dried at 200-250 ° C, and the second layer - at normal temperature.

The method is carried out as follows.

On the dust-free surface of solid

20 The first layer of a primer of a 10-15% solution of solid slimes of aluminum production is first applied in layers of a porous body, dried at 200-250 ° C for 10 39 12 min, and then a second layer of the same composition is applied and dried under natural conditions x After the primer undercoat has dried by any method, a polymer coating is applied and cured under heaters. The chemical composition of the solution of solid slimes of aluminum production, g / l: Na 12.8-20.4; NajCOa 0.4-32.5; NaHCOj 22.4-38.52; N82804 16.2-56.80. PRI m e p. On a solid substrate in the form of keramsit concrete brand 50 for exterior wall panels having a composition, cement 200; expanded clay gravel 357; sand 213; water 250 is applied by brush with one layer of a primer composition containing 10; 12; 15 wt.% Solid sludge aluminum production. The first layer of primer is dried under infrared tin heaters at 230 ° C for 10 minutes. Then a second layer of soil of the same composition is applied with a brush and dried under natural conditions. After such a primer, after 4-6 hours, a polymer powder coating can be applied, followed by curing. . The table shows the indicators of the appearance of the polymer coatings and 1effectiveness of determining the adhesion strength of the coatings and the substrate. A concentration of 10–15% solid aluminum sludge production is determined empirically. The use of a less concentrated solution (5–9%) dramatically lengthens the drying time of the primer, 3 more concentrated (20–40%) reduces the adhesion of the polymer coating to the building product. In addition, after one of the processing of aluminum production, a 10–15% sludge solution is immediately obtained, which can be

concrete

ten

Several small 50 bubbles

12

Smooth, glossy surface

15

Smooth, glossy surface

16.5 17.0

17.5 to be taken out of production, without waiting for these wastes to harden in the sludge field. With a single primer application, it is achieved a full iroggitka construction product with the proposed solution. The first layer of primer is dried out at 200-250 ° C, which corresponds to the formation temperatures of the coating and is provided with the same thermal conditions. If the second layer of primer is also dried at elevated temperature, the wetting of the primed product is impaired with the polymer melt, so it is dried under natural conditions. The modes of application and curing of polymeric powder coatings are significantly times;: are considered for each type of paint and do not depend on the modes of application of the primer layer. The proposed method has been tested for several types of polymer powder coatings, in particular for epoxy powder paints P-EP-17.7, P-EP-219, P-EP-967; polyester paints P-PE-1130; polnacrylate paints П-АК-1138. The primer is necessary so that the moisture present in any construction product does not tear off the polymer coating formed during heating. Applying a primer makes it possible to obtain smooth coatings without bubbles, explosions and craters, which is very important when using building materials with such coatings as facing materials. The proposed method of preparing the surface of a gelboard product prior to the application of polymer powder coatings makes it possible to obtain a high-quality, durable coating. eliminates the use of scarce and expensive organic solvents and allows the utilization of waste products.

5 9774396

Claims (1)

Claims of the invention, the first layer being dried with the method of surface preparation by the builder 200-250 ° C, and the second layer with the normal products for applying the polymer at a different temperature. Powder Coatings by Forming a Soil-Sources of Information, a ground underlay that distinguishes-5 taken into account when examining so that, in order to increase the term 1. Macjevska R.A. et al. Preparation of coating service, primer undercoat for painting. M., 1971. with. 26. form the application of 10-15% water 2. USSR author's certificate No. 664951, solution of solid sludge aluminum pro-cl. From 04 To 41/32, 1976.