Patent ID: 8629072

Claim:
A glass containing at least the following constituents (in % by weight, based on oxide): SiO 2 65-72 Al 2 O 3 11-17 Na 2 O 0.1-8 MgO 3-8 CaO 4.2-12 ZnO 0-10, wherein the weight ratio CaO/MgO is 1.4 to 1.8; wherein no B 2 O 3 , SrO, BaO, ZrO 2 and PbO are present, apart from unavoidable impurities; wherein the glass is free of Li 2 O and K 2 O, apart from unavoidable impurities; which has a hydrolytic resistance in hydrolytic class 1 in accordance with DIN ISO 719; which has an acid resistance at least in acid class 2 in accordance with DIN 12116; and which has an alkali resistance at least in alkali class 2 in accordance with DIN ISO 695.