| 摘要 |
<p>The invention relates to a glass composition with 50-54 % SiO2 and 30-33 % PbO, wherein the overall amount of K2O and Na2O ranges between 9 and 13 % and the amount of B2O3 together with ZnO is 4-8 %, wherein the amount of B2O3 alone is less than 4 %.</p> |
