GYPSUM COMPOSITION FOR LAYING FALSE TOOTH

摘要

A gypsum composition for denture investment consists of 100 parts by weight of a mixture of 50-90 parts by weight of alpha -Gypsum hemihydrate ( alpha -CaSO4.1/2H2O) with 10-50 parts by weight of beta -Gypsum hemihydrate ( beta -CaSO4.1/2H2O) and 0.2-2.0 parts by weight of a soluble potassium salt. As the soluble potassium salt, use may be made of one or more of potassium sulfate, potassium chloride and potassium tartrate. The gypsum composition may further include 0.5-5.0 parts by weight of dihydrate gypsum.