Electro-optical property polymer-dispersed liquid crystal composite film having modified polymer matrix, cell using the film, and method for producing the same

摘要

A polymer/liquid crystal dispersion includes a liquid crystal, a surfactant and a water soluble copolymer obtained by polymerizing a hydrophilic monomer with one or more hydrophobic monomers. The concentration of the hydrophobic monomer may be 14 to 25% by weight based on the combined weight of the hydrophobic monomer and the hydrophilic monomer. The hydrophobic monomer may be styrene, 3-(trifluoromethyl)styrene, nonylphenol, methacryloyl chloride, methacrylate, and acrylate. The hydrophilic monomer may be acrylamide, acrylonitrile or acryloyl chloride. Preferably, the hydrophilic monomer is acrylamide or a derivative thereof and the hydrophobic monomer is styrene, methyl methacrylate or vinyl acetate. The liquid crystal may be a nematic liquid crystal formed of an azomethine compound or an azo compound. The water soluble copolymer, the liquid crystal, the surfactant and water may form a liquid crystal/aqueous polymer solution. In this case, the concentration of the liquid crystal in the liquid crystal/aqueous polymer solution is preferably in the range of 50 to 70% by weight and the concentration of the surfactant is preferably in the range of 1 to 5.5% by weight. A composite film may be formed from the polymer/liquid crystal dispersion and a pair of plates sandwiching the polymer liquid crystal emulsion.