Patent ID: 7104090
Filing Date: 2006-09-12
Classification: C03B,C03C

Abstract:
1. A method of manufacturing a polarizing glass article comprising the steps of: melting a glass batch containing a halide; cooling and shaping the melt into a glass article; ion-exchanging silver or copper metal into the surface of the glass article; subjecting the glass article to an elevated temperature for a period of time sufficient to generate and precipitate silver or copper halide crystals in a surface layer of the glass; elongating the glass article under stress at a temperature above the annealing point of the glass to elongate the crystals in the direction of the stress; and exposing the elongated glass article to a reducing atmosphere at an elevated temperature to initiate reduction of at least a portion of the silver or copper halide crystals to silver metal; wherein the ion exchange occurs after cooling and shaping the melt into an article and before subjecting the glass article to an elevated temperature treatment for a period of time sufficient to generate and precipitate silver or copper halide crystals in a surface layer of the glass.