ORGANIC POLYACID/BASE REACTION CEMENT

摘要

For making a cement such as a dental cement by reacting an organic polyacid (such as polyacrylic acid or polyvinylphosphonic acid or a copolymer of these) with an ion-leachable glass as the base, the invention offers a glass containing the cations Al, Si, Ca and Zn wherein Si:Al>1.5 and Zn is 30-70 percent of those cations. The glass is made by heat treating an aqueous paste of Al, Si, and Ca oxides, such as bentonite, with ZnO and a precursor of ZnO such as zinc acetate, whereby the zinc forms a layer on the glass and is also incorporated as a glass network former. The setting of the cement is speeded and sharpened by using around 2 % MgCl2.