Patent ID: 6635398
Filing Date: 2003-10-21
Classification: G03G

Abstract:
A dry toner comprising toner particles containing at least a binder resin, a colorant and a wax component, and an external additive, wherein;(1) the binder resin contains a component formed from a monomer selected from the group consisting of butadiene, isoprene and chloroprene; (2) said toner has a main glass transition temperature (Tg) of from 40Â° C. to 70Â° C. as measured by differential scanning calorimetry (DSC); (3) where specific surface area measured by the BET method when the toner is left for 72 hours in an environment of 23Â° C. atmospheric temperature and 65% relative humidity is represented by A (m2/g) and specific surface area measured by the BET method when the toner is left for 72 hours in an environment of 50Â° C. atmospheric temperature and 3% relative humidity is represented by B (m2/g), the toner satisfies the following relationship: 0.8&lE;A&lE;4.0, 0.80&lE;(B/A)&lE;1.05; (4) in a toner's number-based circle-corresponding diameter/circularity scatter diagram as measured with a flow particle image analyzer, the toner has a circle-corresponding number-average particle diameter D1 of from 2 &mgr;m to 10 &mgr;m and has an average circularity of from 0.950 to 0.995 and a circularity standard deviation of less than 0.040; and (5) the toner has, in its molecular-weight distribution of tetrahydrofuran (THF)-soluble matter as measured by gel permeation chromatography (GPC), a main-peak molecular weight in the region of from 2,000 to 100,000 and contains a THF-insoluble matter in an amount of from 5% by weight to 60% by weight.