| 摘要 |
PROBLEM TO BE SOLVED: To provide a positively charged toner excellent in durability and stability that prevents, neither increase of scumming (fog) of a white background portion nor deterioration in image density when used repeatedly in a copying machine or a printer, and prevents increase in image fog and neither lowering of transfer rate nor in-machine scattering from being caused even by a stress under a high temperature environment. SOLUTION: The positively charged toner comprises toner base particles containing at least a binder resin, a colorant, a charge control resin and a release agent and an external additive, wherein the relation between the BET specific surface area (A) of the toner and the BET specific surface area (B) of a heated toner obtained by heating the above toner at 50°C for 144 hours and then cooling the toner satisfies the conditional expression (a): [(A)-(B)]/(A)≤0.15. COPYRIGHT: (C)2007,JPO&INPIT
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