| 摘要 |
PURPOSE:To sharpen the grain size distribution of a polymerized toner and to improve a triboelectrostatic charge characteristic by subjecting a specific monomer compsn. to a suspension polymn. CONSTITUTION:The polymerized toner is prepd. by subjecting the monomer compsn. (A) to the suspension polymn. in a dispersion medium contg. a hardly water soluble inorg. dispersant (e.g., aluminum phosphate) and having 2.5-5pH. A polymerizable monomer (e.g., styrene) and 0.01-0.5wt.%, based on the weight of the monomer, nigrosine dye (e.g., 'C.I. No. 50415proportional ') are incorporated into this compsn. A; the incorporation of a coloring agent, magnetic particles, flowability reforming agent, polymn. initiator and crosslinking agent, etc., therein is possible as well. The coarse toner particles are formed at a larger ratio if the pH of the dispersion medium exceeds 6. The outflow of the magnetic particles arises in the case of producing the magnetic particle-contg. if the pH is below 2.5. Both cases are, therefore, undesirable. |
