| 摘要 |
PURPOSE:To obtain excellent electrostatic chargeability and developability without using carrier particles by incorporating a nitrogenous polar functional group and conductive component into developer particles so as to coexist on the surfaces of said particles and further regulating the electric resistivity of the developer particles to a specific value. CONSTITUTION:A discontinuous layer of a conductive component is formed on the surface layer of insulating particles contg. a binder resin contg. a monomer component having a nitrogenous functional group and the electricity resistivity over the entire part of the developer particles is regulated to >=10<14>OMEGAcm. Such a compd. as shown in the formula is used as the monomer component having the nitrogenous polar group. Such monomer may be used as, for example, a homo polymer or a copolymer with the monomer of the binder resin. The developer having such compsn. provides satisfactory and stable electrostatic chargeability, developability and transferability since the developer contains the nitrogenous polar functional group and the conductive component coexisting therein and has the high electric resistivity. Electric charge is quickly obtainable and the image having excellent solid black, fine lines and graduation reproducibility free from a photographic fog is obtd. |
