摘要 |
<p>An X-ray-opaque glass is disclosed which is free of BaO and PbO except for at most impurities and has a refractive index nd of from 1.50 to 1.58 and a high X-ray opacity with an aluminium equivalent thickness of at least 300%. The glass is based on the system Si02 - Al203 - SrO - R20 with additions of La203 and Zr02. The glass has very good chemical resistance and can be used, in particular, as dental glass or as optical glass.</p> |