| 摘要 |
PURPOSE:To prevent generation of excluded volume effect of dispersed particles themselves of a resin for liquid developer for electrostatic photography and to obtain satisfactory picture image by forming the resin from a polymer being insoluble in a solvent and having amide groups, a monomer being soluble in the solvent but insolubilized by the polymer, and a monomer being soluble in the solvent but forming a polymer after polymn. CONSTITUTION:A liquid developer for electrostatic photography is used after polymerizing a monomer A and a monomer B with the developer contg. resin particles dispersed in a hydrocarbon solvent having high electric insulation in the presence of a polymer S being insoluble in the solvent but having amide groups. The monomer A is selected from monomers being soluble in the solvent but forming insoluble polymer after polymn., and the monomer B is selected from monomers being soluble in the solvent and forming also soluble polymer after polymn. Thus, electrostatic mutual repulsive effect due to the Coulomb's force attributed to the dispersed particles themselves and the excluded volume effect due to the mutual repulsion of elevated stabilizing dispersed polymer are eliminated, and the lowering of effective surface potential of the electrostatic material is prevented, the disturbance of picture image due to ghost in the neighbourhood of picture image is eliminated, displaying a distinct picture image. |
