BOROSILICATE GLASS FOR XENON FLASH TUBE, ENVELOPE AND XENON FLASH TUBE

摘要

PROBLEM TO BE SOLVED: To obtain a borosilicate glass markedly reduced in the attenuation of the quantity of light of xenon flash tubes made thereof by designing its average coefficient of linear thermal expansion in a specific temperature region at a specific value and its annealing point at a specific temperature or higher. ;SOLUTION: This boroslicate glass, which comprises 60-80 wt.% of SiO₂, 1-13 wt.% of B₂O₃, 1-10 wt.% of Al₂O₃, 0-5 wt.% of ZrO₂, 0-10 wt.% of Li₂O and 4-12 wt.% of (Li₂O+Na₂O+K₂O) with a weight ratio: SiO₂/B₂O₃ of 5.2, has an average coefficient of linear thermal expansion of 35 to 5510^-7/C and an annealing point of 560C. Furthermore, if needed, this glass is incorporated with respective appropriate amounts of components such as MgO, CaO, SrO, BaO, ZnO, TiO₂, P₂O₅, SO₃, F₂, Cl₂, Sb₂O₃ and/or As₂O₃ for the purpose of regulating its viscosity and/or improving its weatherbility, solubility and clarity; in particular, in order to raises its annealing point, this glass may be incorporated with up to 10 wt.% of alkaline earth metal oxide(s) such as MgO, CaO, SrO and/or BaO.;COPYRIGHT: (C)1999,JPO