PURPOSE: To obtain a toner having a narrow grain size distribution, and excellent uniform electrostatic charging property, developing property, etc. by swelling the fine particles obtd. by an emulsion polymn. with a solvent contg. a dye or pigment and a polymn. initiator, and polymerizing a monomer in the swollen particles in an aq. soln. contg. a monomer.
CONSTITUTION: A monomer of styrene, (meth)acrylate, etc. is first subjected to an emulsion polymn. whereby fine monodisperse particles having 0.1W3μ grain size are obtd. The particles are then immersed in a solvent which contains a dye or pigment such as carbon black, nigrosine or the like and which swells the resulted fine particles but does not dissolve the partciels. The swollen particles are again dispersed in the water and while a mixture of the monomer and a polymn. catalyst is added, the monomer is adsorbed on the particles and is polymerized. The spherical monodisperse toner having about 10μ is thus obtd. The toner which does not require classification and has uniform performance and excellent developing property, fixability and transfer property is obtd.
OOSAKI ICHIROU
NAKAHARA TOSHIAKI
