| 摘要 |
<p>A thermally crystallizable glass consisting essentially in weight percent as calculated from the batch of 45-70%, SiO2, 8-20% MgO, 8-15% MgF2 5-35% R2O+ RO, wherein RO ranges from 0-25% and consists of one or more oxides selected in the indicated proportions from the group consisting of 0-20% K2O, 0-23% Rb2O and 0-25% Cs2O and wherein RO ranges from 0-20% and consists of oxides selected from the group consisting of SrO, BaO and CdO, 0-7% ZrO2, 0-2% Al2O3 and 1-9% total of ZrO2 + Al2O3 and 0-10% total of glass colourants crystallizable to a tetrasilicic fluorimica glass-ceramic material exhibiting excellent stain resistance. Articles having reduced stain resistance, in particular dental constructs made a glass-ceramic of the above composition are particularly useful.</p> |
