Photochromatischer Glasartikel und Verfahren zu dessen Herstellung

摘要

This invention relates to the manufacture of glass articles which exhibit photochromic behavior and which exhibit very high mechanical strengths through the development of a surface compression layer therein by an ion exchange process. More particularly, this invention relates to glasses wherein silver halide crystals impart photochromic properties and wherein the ion exchange involves alkali metal and silver ions.