Slip cast body from alpha calcium sulphate hemihydrate - of controlled particle size range provides hard, crack free ground surface

摘要

Slip casting body comprising alpha-calcium sulphate hemihydrate, a liquefier and a set retarder, has at least 50 wt.% of the hemihydrate of particle size range 6-60 mu (20-30 mu). The body further contains 0.2-0.9(0.4-0.6) wt.% K2SO4. Used for making slip cast articles, floor and ground coatings. The slip casting body is fluid and self levelling while producing improved strength without fissuring. Efflorescence does not occur as in prior art since the compsn. does not include free lime. A firm hard surface is obtd. The restriction of particle size range prevents segregation and sedimentation in the slurry, so that a uniform compsn. is poured during casting. The amt. of liquefier used is considerably reduced compared with prior art.