METHOD FOR MANUFACTURING DIALS FOR WATCHES AND DIALS FOR WATCHES MANUFACTURED ACCORDING TO SAID METHOD

摘要

1398315 Glass ceramic watch dials LES FABRIQUES D'ASSORTIMENTS REUNIES 15 Aug 1972 28828/72 Heading C1M Glass-ceramic dials for watches are produced by melting a glass-forming batch, adding to the batch at least one nucleating agent in an amount of 1-28% by weight, casting and moulding the melt to form the dials, cooling the dials to a temperature below the annealing point of the glass, reheating the glass dials to form crystal nuclei, heat treating the glass dials to effect crystal growth and thereafter slowly cooling the dials. The number of specific compositions are given employing P 2 O 5 or TiO 2 as nucleating agent. Colouring oxides such as CoO, Cr 2 O 3 , MnO, FeO and SnO are added to the glass melt, usually without mixing so as to produce flame effects.