SILICON OXIDE BASED ARTICLES

摘要

Particularly shaped articles constituted by silicon oxide, as such or with suitable additives, prepared by room temperature molding according to a process comprising: preparation of a sol starting from a silicon alcoxide, o r from a silicon alcoxide and at least a precursor of at least one of the additional elements; hydrolysis of the sol obtained thereby; addition of colloidal silica; pouring the resulting mixture into the desired mould; sol gelling and fast removal of the solid product; gel drying; gel densification by means of a thermal treatment at temperature ranging from 900 ~C to 1500 ~ C. The articles can be used as preforms for the optical fiber spinning.