Preparation and application of poly(vinyl alcohol) microcapsules containing azo dye

Poly(vinyl alcohol) microcapsules containing disperse red 1 (DR1), a photor esponsive group. were prepared by a phase separation method (coacervation). The structure of PVA microcapsules was a core/shell type microsphere with DR1 used as a core material encapsulated with PVA. From a SEM analysis, the particle size was in the range of 2-6 mum. We also investigated the possib ility of the application of the microcapsules as optical switching device m edia.