| 摘要 |
<p>Pierson-Stockey 8-63 PHOTOSENSITIVE GLASSES This invention is concerned with the preparation of glass articles wherein a portion thereof is opaque and another portion thereof is transparent and, optionally, integrally colored. The opaque portion is produced through the thermal reduction and precipitation of a controlled number of submicroscopic particles of at least one metal selected from the group of copper, gold, palladium, platinum, and silver with the subsequent nucleation and growth of NaF crystals on said metal particles to a size sufficient to scatter visible light. The transparent portion is developed through the photoreduction of at least one photosensitive metal selected from the group of copper, gold, and silver to produce additional submicroscopic particles of said metals upon which NaF crystals are nucleated and grown, but which remain in a size too small to scatter visible light. The presence of copper or gold alone gives rise to a single color, whereas the inclusion of silver permits a full spectrum of colors to be produced. Where silver is present, microcrystals of NaF containing a silver halide selected from the group of AgCl, AgBr, and AgI are grown upon which a coating of metallic silver is developed or within which metallic silver is deposited. The method involves sequences of exposures of the glass to high energy or actinic radiation followed by heat treatments.</p> |
