SU594073A1 - Method of manufacturing coloured silicate articles - Google Patents

Description

The invention relates to the coloring of silicate products and can be used for coloring silicate bricks in solutions of mineral salts and organic dyes.

The method of coloring silicate products by impregnating them in solutions of mineral salts under vacuum is known. The disadvantage of this method is that its use is impractical for painting silicate bricks, since all the painting operations are done manually and it is difficult to maintain the temperature at the same level for a long time.

 There is also known a method of making colored silicate products, which includes heat-moisture treatment in an autoclave and impregnation in a painting chamber under pressure. Impregnated products are dried 2. A disadvantage of this method is the considerable time of drying products with a large water penetration. This method is closest to the invention.

The purpose of the invention is to reduce the time of the technological production cycle and improve the quality of coloring.

This is achieved by the fact that the heat-moisture treatment of products in an autoclave is carried out in two stages with equal isothermal exposure, between which the hazardous material is impregnated.

Production technology is as follows.

The raw material laid on the trolleys is subjected to preliminary autoclave treatment, moreover, the isothermal holding time is halved compared with the isothermal holding time required for conventional autoclaved silicon silicate products.

The semi-finished product of 50-60% strength obtained in this way from the strength of a brick that has undergone a full autoclave treatment cycle is sent to the trolleys in the painting chamber, where it is impregnated with a solution of mineral salt, for example, ferrous sulphate for 5-1 O mn when the solution is melting kgf / cm The painted depth of 10–12 mm of the semi-finished product was directed to the autoclave of the final processing t and to the autoclave, similar to that of the preliminary autoclaving. In the course of the final autoclave treatment, the moisture accumulated in the pores of the semi-finished product under the action of high temperature evaporates and the strength of the bricks is built up under normal conditions in a specific grade paoa. Drying of painted products takes place under conditions similar to drying of a common silicate brick when the pressure in the autoclave is depressed. Example. Samples prepared from a mixture containing 93% quartz sand and 7% lime with a moisture content of 6% were painted. From a mixture of rtformalized sample-cylinders with a height and diameter of 6 cm at a press pressure of 200 kgf / cm. Further processing of the raw material was carried out according to the following mode: a) pre-autoclave treatment .1,5 + 4 + 1.5 h, with a steam reduction At kgf / cm , b) coloring of the semi-finished product with a 15% solution of sulfate extract for 10 minutes at a solution pressure of 2 kgf / cm} c) final autoclave treatment of the semi-finished product according to the 1.5 + 4 + 1.5 h mode at a vapor pressure of 8 kgf / cm . For comparison, the samples were dyed by a known method according to the mode: a) raw autoclave treatment according to the 1.5 + 8 + 1.5 h mode at a vapor pressure of 8 kgf / cm; b) coloring of finished products with a 15% solution of ferrous sulphate for 10 minutes at a pressure of 2 kgf / cm j cm . Painted samples were tested for strength, moisture content and color change. The test results are shown in the table.