COMPOSITION FOR PRODUCTION OF MAIN LAYER OF DECORATIVE - FACING MATERIAL Russian patent published in 1994 - IPC

FIELD: production of building materials. SUBSTANCE: composition contains, percent by mass: granite siftings with fractions within 0.14 to 1 mm - 5 to 20; granite siftings with fractions less than 0.14 mm - 57 to 66; broken glass - 20 to 28 and soda-sulfate mixture - 1 to 3. Granite siftings, broken glass and soda-sulfate mixture are subjected to drying and combined comminution up to the passage through sieve with mesh <0.14 mm. Granules of granite siftings with fractions within 0.14 to 1 mm weighted out in the preset amount are changed into a mixer and moistened with water to a moisture content from 5 to 7%. Then the mix of granite siftings with fractions of 0.14 mm, broken glass and soda-sulfate mixture is changed into the mixer to the moistened granules of granite siftings of fraction within 0.14 to 1 mm, and agitation is continued. The prepared mix is changed into a mould, whose bottom is covered with a layer of sand. Moulds are placed in furnace and subjected to thermal treatment at a temperature of 870 to 930 C, holding time is 30 min. Physical-mechanical indices are as follows: compressive strength - 45.5 to 52.1 MPa, bending strength - 12.5 to 14.1 MPa, impact resistance - 85 to 90 N cm, water absorption - 0.9 to 2.9%. EFFECT: enhanced quality. 3 tbl