| 摘要 |
<p>PURPOSE:To produce an electrophotographic toner not causing blocking and having a long service life even when a bonding resin having a low softening point and fixable at low temp. is used by forming an isocyanate or polyisocyanate hardened coating film on the surface of each of the matrix particles of a toner contg. a bonding resin and a colorant. CONSTITUTION:A hardened coating film is formed on the surface of each of the matrix particles of a toner contg. a bonding resin and a colorant by a reaction of active hydrogen existing on the surface with an isocyanate or polyisocyanate to produce the objective electrophotographic toner. The isocyanate is, e.g. methyl isocyanate, isopropyl isocyanate or phenyl isocyanate. The polyisocyanate is, e.g. 2,4-tolylenediisocyanate. Polyester resin contg. hydroxyl groups is used as the bonding resin or a copolymer obtd. by copolymerizing polyethylene, a styrene-acrylic ester copolymer or epoxy resin with an active hydrogen-contg. monomer may be used.</p> |
