Effect of Additive Agent on Darkening and Fading Characteristics of Germanate Glass

Abstract

The effects of minor components added to the base glass of 90GeO₂·10Na₂S (mole %) on darkening and fading characteristics of the glass during and after U.V. irradiation were investigated. Ce₂O₃, Eu₂O₃, ZrO₂, Mn₂O₃, V₂O₅, PbO, TiO₂, FeO and Cu₂O were used as the additive agents. Among these additive agents, Ce₂O₃, Eu₂O₃ and ZrO₂ were found to be effective on the acceleration of the darkening and fading characteristics of the base glass. In particular, Eu₂O₃ was the most effective. Furthermore, it was found that the ability of the additive agent to enhance the characteristics of the glass depended upon the kind and the concentration of the additive agent.