Preparation And Characterization Of Dual Colored Microcapsule Type Electrophoretic Display Prototype

A series of dual colored microcapsule type electrophoretic display （EPD）prototypes were prepared and studied in this paper. The main research contentsincluding: study on the formulation of electrophoretic suspensions contained C. I.Pigment Red254（PR254）, C. I. Pigment Yellow13（PY13） and C. I. Pigment Yellow181（PY181）, respectively; the preparation of urea-formaldehyde microcapsulescontained dual-colored electrophoretic suspensions via in situ polymerization; studyon the coating process and preparation of microcapsule type EPD prototypes.The formulations of electrophoretic suspensions were investigated by orthogonalexperiment method. Influence factor of concentration of T-151, CTAB, Span85andCH-5on the suspension properties were discussed. The microcup EPDs werefabricated by filling the dual-colored electrophoretic suspensions into a7-sectiondisplay prototype. The contrast ratio of these displays is1.65,1.22and1.28,respectively.Functional microcapsules were prepared via in situ polymerization. This paperdiscussed the factors affecting the appearance and properties of microcapsules, suchas mass ratio of wall materials and core materials, the quantities of crosslinking agentand pH values. The optimal production conditions were confirmed. The microcapsulesshowed good surface topograph and suitable sizes, and were applied successfully toprepare EPD prototypes.After the microcapsules were mixed with binders, the mixture was spread on anIndium tin oxide polyester film by a blade coating machine.The effects of binders,thickness of layers and drying method on the film properties were investigated in thispaper. Dual-colored microcapsule type EPD prototypes were prepared usingPR254/TiO₂suspensions, PY13/TiO₂suspensions and PY181/TiO₂suspensions,respectively.