ELECTROVACUUM GLASS Russian patent published in 1995 - IPC

FIELD: glass industry. SUBSTANCE: electrovacuum glass has, wt.-%: silicon oxide 72.9-75.7; boron oxide 17-19; aluminium oxide 1.1-1.5; sodium oxide 3.5-4.5; potassium oxide 1.2-1.8; ferric oxide 0.1-0.3; cerium oxide 0.1-0.3; antimony oxide 0.2-0.4, and zirconium oxide 0.1-0.3. Transmission coefficient in UV-spectrum range at wavelength 290 nm is 0.2-0.6, glass solarization is 0%. Glass is used for making of fluorescent lamp shells. EFFECT: enhanced quality of glass. 1 dwg, 1 tbl