| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a developer excellent in charge stability, flowability and durable stability by incorporating a coloring agent, a binder resin and a hydrophobic rutile/anatase mixed crystal titanium oxide. SOLUTION: A toner, in which the hydrophobic rutile/anatase mixed crystal titanium oxide is externally added in the toner particle containing the coloring agent and the binder resin, is incorporated in the developer. The hydrophobic rutile/anatase mixed crystal titanium oxide is preferably contained by 0.03-3.0 wt.% in the toner particle. In the case of mixing the hydrophobic rutile/anatase mixed crystal titanium oxide with a rutile or anatase titanium oxide having different hydrophobicity, the mixing ratio is 1:8 to 1:1, 0.02-3.0 wt.% mixture is contained in the toner particle and the ratio of the type rutile to the type anatase is preferably 5:95 to 90:10.</p> |
