| 摘要 |
The covering layer of the coating comprises brick dust and finely divided mineral aggregates, particularly coarse siliceous sand, which are bound by a hydraulic mortar, such as a mortar used particularly for paving. For the preparation, the brick dust, the mineral aggregates and the solid components of said mortar are dry mixed and the dry mixture is applied to the prepared background, is levelled and pressed, for example by means of rollers. Then, it is sprayed with water to wet uniformly the pressed layer of the mixture. The mortar contains cement, sand and/or calcareous rock, methylcellulose and, as desired, vinyle chloride and vinyle propionate copolymer, polycondensate of melamine-formaldehyde, polyacrylic amide, trass and/or a fibrous material, preferably asbestos. |
