SPRÜHTROCKNUNGSVERFAHREN ZUR HERSTELLUNG FARBSTOFFHALTIGER TEILCHEN

摘要

According to a first aspect of the invention, a process is provided for the preparation of amorphous particles comprising a homogeneous distribution of one or more dyes encapsulated by an amorphous, siliceous encapsulating agent, the process comprising:
(a) providing a precursor of the encapsulating agent in liquid form;
(b) providing the one or more dyes in liquid form;
(c) mixing the liquid forms;
(d) aerosolizing the mixture to form droplets comprising the one or more dyes and encapsulating agent; and
(e) heating the droplets to form the particles comprising the one or more dyes encapsulated by the siliceous encapsulating agent;
wherein at least one of the liquid forms provided is aqueous and the or each aqueous liquid form is acidic. According to a second aspect of the invention, encapsulated dyes made by the processs of the first aspect of the invention are provided.