Abstract: A process for producing encapsulated metal colloids useful as inorganic colored pigments, including, reacting one or more glass-forming components according to the sol-gel process to obtain a sol dispersing a metal salt in the resulting sol in the presence of an additional reducing agent to form metal colloids, converting the resulting dispersion into xerogel-encapsulated metal colloids by spray drying, heating the resulting xerogel-encapsulated metal colloids to density them. The present invention relates, furthermore, to inorganic colored pigments, in particular producible by the process of the invention, including metal colloids produced from metal salts and encapsulated in an encapsulation, the encapsulation being produced from glass-forming components according to the sol-gel process and being densified to a xerogel or glass, the proportion of metal colloid in the capsules being at least 80%.

Abstract: A process for producing encapsulated metal colloids useful as inorganic coloured pigments, including, reacting one or more glass-forming components according to the sol-gel process to obtain a sol dispersing a metal salt in the resulting sol in the presence of an additional reducing agent to form metal colloids, converting the resulting dispersion into xerogel-encapsulated metal colloids by spray drying, heating the resulting xerogel-encapsulated metal colloids to density them. The present invention relates, furthermore, to inorganic coloured pigments, in particular producible by the process of the invention, including metal colloids produced from metal salts and encapsulated in an encapsulation, the encapsulation being produced from glass-forming components according to the sol-gel process and being densified to a xerogel or glass, the proportion of metal colloid in the capsules being at least 80%.

Abstract: A photochromic coating composition contains a silicon-containing precondensate derived from a hydrolysable silane containing a polymerizable functional group on a hydrolysis-stable radical, a photochromic dye, a stabilizer, and nanoscale particles. The coating composition, when applied to transparent plastic and glass substrates and cured, gives a coating having high light stability and good scratch resistance.

Abstract: The invention relates to transparent organic/inorganic composites with low hydroxyl group content, based on silicic acid heteropolycondensates having extremely low water uptakes. These composites are obtained for example by nonhydrolytic condensation of chlorosilanes with polymerizable groups and optionally fluorinated groups, with the help of a condensation agent (e.g., t-butanol) capable of non-hydrolytic condensation of this chlorosilane, and thermal and/or photochemical polymerization of the obtained condensation product, preferably in the presence of preferably fluorinated organic monomers.