RAOSKIVA FOER EN BYGGNADSSKIVA PAO GIPSBASIS SOM FRAMSTAELLS ENLIGT UPPRULLNINGSFOERFARANDET

摘要

The invention relates to a raw board for building boards to be prepared by the winding-up process on a gypsum basis, which contains ground cellulose and/or waste paper fibres as wet material support fibres, gypsum as a binder and hydraulic cement and additives as other constituents. Such a raw board is distinguished by the following composition: Gypsum in the form of CaSO4 . 1/2 H2O 30-85% Hydraulic cement 10-30% Blast furnace slag, fly ash maximum 50% Kieselguhr, perlite, vermiculite, limestone powder, sand or similar fillers maximum 50% Cellulose and/or waste paper fibres, degree of grinding 20-80 DEG SR maximum 3-30% Mineral fibres, glass fibres, glass, rock or slag wool or the like maximum 20% Organic fibres such as sisal, hemp, polymer fibres or the like maximum 20% Substances delaying the setting of the gypsum 0.1-2% Flocculating agents maximum 200 ppm.