1. An electrophoretic slurry composition comprising: a fluid medium; charged particles dispersed in the fluid medium; and polymer beads dispersed in the fluid medium, wherein the polymer beads are contained in an amount of 1 to 10 parts by weight with respect to 100 parts by weight of the composition, wherein the charged particles are contained in an amount of 30 to 80 parts by weight with respect to 100 parts by weight of the composition, and wherein the polymer beads comprise at least one repeating unit selected from the group consisting of repeating units represented by the following formulas 1 and 2: wherein R 1 is independently hydrogen, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, an aryl group having 6 to 30 carbon atoms, an alkylaryl group having 7 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms, a cycloalkyl group having 4 to 20 carbon atoms, an amide group substituted or unsubstituted with an alkyl group having 1 to 20 carbon atoms, and an alkoxycarbonyl group having 1 to 20 carbon atoms; and R 2 is independently hydrogen or an alkyl group having 1 to 3 carbon atoms.