| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a two-component developing method and two-component developer, in which electrifying performance, carrying ability, stress resistance are excellent and high image quality and a long life are ensured, with respect to the two-component developing method using a two-component developing machine having two or more magnet rolls that are used in a printer which is operated at high speed, for example a linear velocity of >=370 mm/sec, preferably >=500 mm/sec. SOLUTION: In the two-component developing method that uses the two-component developing device having two or more magnet rolls and uses the two component developer including toner and carrier, ferrite carrier that satisfies the following conditions (a) and (b) is used: (a) magnetization measured when a magnetic field of 1 kOe is applied is 45 to 75 emu/g; and (b) a ratio between magnetization A measured when 1 kOE is applied and magnetization B calculated by a primary approximate expression (measured magnetization A/calculated magnetization B) is <=0.90, in which a relationship between magnetization measured when a magnetic field of -0.5 to 0.5 kOe is applied and the applied magnetic field is expressed by the primary approximate expression passing through an original point. The two-component developer is used for the two-component developing machine having the two or more magnetic rolls, and contains the ferrite carrier.</p> |
