Preparation and characterization of microcapsules containing particulate phosphorescent agent with suspension polymerization

Microcapsules containing particulate phosphorescent agent (strontium aluminate) were prepared by the suspension polymerization method and characterized about a few items such as the mean diameters, the content, the inner structure and the afterglow luminance property. Furthermore, the fundamental experiments were conducted to investigate how the dispersing feature of particulate phosphorescent agent affects the afterglow luminance property. In the experiment, the concentration of oil soluble surfactant, the crosslinking agent species, the added weight of the phosphorescent agent and the pre‐bulk polymerization time were mainly changed stepwise. Afterglow luminance of particulate phosphorescent agent gradually decreased with the afterglow time and considerably decreased because of soaking them in water. Decline of afterglow luminance because of soaking in water could be prevented by microencapsulation. Afterglow luminance of the multicore type microcapsules was found to be higher than that of the core–shell type microcapsules. The content of particulate phosphorescent agent could be increased by performing pre‐bulk polymerization and increasing the concentration of the oil soluble surfactant.