Two or more hydrophilic polymers that are not soluble in each other at a particular concentration and temperature, but which have a positive spreading coefficient in solution, are used to form multi-layered polymeric microspheres. The multi-layer microspheres produced by the method are distinguished...http://www.google.fr/patents/US6511749?utm_source=gb-gplus-shareBrevet US6511749 - Preparation of multiwall polymeric microcapsules from hydrophilic polymers
Preparation of multiwall polymeric microcapsules from hydrophilic polymers
