Patent ID: 6395443
Filing Date: 2002-05-28
Classification: G03G

Abstract:
A toner for developing an electrostatic image, comprising a binder, a coloring agent and a charge controlling agent and having the following characteristics (a), (b), (c), (d) and (e):(a) said toner has a weight average particle diameter of 6.0 to 11.5 &mgr;m, a total particle number N and a total weight W; (b) that portion of said toner which has a particle diameter of 5.04 &mgr;m or less accounts for greater than 15% but not greater than.60% of the total number N of said toner and has a number average particle diameter of 4.0 to 4.5 &mgr;m; (c) that portion of said toner which has a particle diameter of greater than 5.04 &mgr;m but not greater than 12.7 &mgr;m accounts for 40 to 90% of the total number N of said toner and has a weight average particle diameter of 6.0 to 9.5 &mgr;m; (d) that portion of said toner which has a particle diameter of 16 &mgr;m or more is not more than 2% based on the total weight W of said toner; and (e) that portion of said toner which provides a number average particle diameter of 4.0 to 4.5 &mgr;m has such a content C1% by weight of the charge controlling agent that gives a ratio of C1/CT of 1.00 to 1.10, where CT is a total amount, in terms of % by weight, of said charge controlling agent in said toner.