| 摘要 |
PURPOSE:To obtain a toner for developing electrostatic charge images which has excellent moisture resistance and frictional chargeability and forms a stable image by dispersing a high dielectric material having a prescribed specific dielectric constant and specific volume resistivity together with an electric charge controlling agent and coloring agent into a polymerizable monomer and suspension-polymerizing the same in an aq. medium in the presence of a suspension dispersion stabilizer. CONSTITUTION:The high dielectric material having >=10 specific dielectric constant at an ordinary temp. and >=1X10<10>OMEGA.cm specific volume resistivity is dispersed together with the electric charge controlling agent and coloring agent into the polymerizable monomer. The dispersion is then suspension- polymerized in the aq. medium in the presence of the suspension dispersion stabilizer to obtain the toner for developing electrostatic charge images. Ba titanate, Mg titanate, Sr titanate, Zr titanate, lead titanate, etc., are used for said high dielectric material. The grain size thereof is preferably <=3mum, more particularly preferably <=1mum. The amt. of said material to be added is 0.3-50wt%, more preferably 0.5-30wt%. |
