Production of photochromic laminate, useful e.g. for sunglasses, uses photochromic solution prepared by reacting copper sol, copper halide and/or silver carbonate, (hydrated) oxide or hydroxide dispersion with oxidant

摘要

Production of photochromic laminate, prepared by reacting copper sol, copper halide and/or silver carbonate, (hydrated) oxide or hydroxide dispersion with oxidant. The process concerns production of a laminate with photochromic switching, which consists of photochromically passive layer(s) and a photochromically active layer, comprising a light-permeable matrix of polymer mixture containing silver salts and suitable oxidant(s), such that the reaction equilibrium remains constant at a predetermined level in light of over 200 W/m2. The process involves preparing a dispersion containing the reactants and converting this to a film. The novelty is that the photochromic solution is prepared by preparing a copper sol, copper iodide, bromide or chloride dispersion or mixture of these and also a silver carbonate, oxide, hydrated oxide or hydroxide dispersion; and reaction with an oxidant in the presence of a halide or another hardly soluble silver salt.