The synthesis of polymer particles is reported, which are composed of (I) a spherical colloidal core particle, (2) encapsulation of such seed particles with the inimer 4-vinylbenzyl N,N-diethyldithiocarbamate (VBDC) providing the formation of a hyperbranched structure by a living radical mechanism, and followed by (3) a grafted polymer brush prepared by photo-induced atom transfer radical polymerization (ATRP). The particle sizes (number-average particle diameter D-n = 190-300 nm) were controlled by varying the temperature and size distributions were extremely narrow (D-w/D-n = ca. 1.0001). By variation of the particle size, the brilliant color could be varied throughout the visible spectrum. The morphology of the core-shell particles and the properties of corresponding film were characterized by Fourier transform infrared (FT-IR), dynamic light scattering (DLS), reflection spectrum measurements, and scanning electron microscopy (SEM). (C) 2009 Elsevier Inc. All rights reserved.