| 摘要 |
PURPOSE:To obtain a dry developer suitable for a laser printer with high resolution, etc. by mixing a magnetic toner having specified electric resistance and a specified average particle size with a magnetic toner having specified electric resistance and a smaller average particle size than said magnetic toner. CONSTITUTION:A mixture of 70-95pts.wt. toner A consisting of a thermoplastic resin and magnetic powder and having 30-60mum average particle size and >=10<11>OMEGA.cm electric resistance with 30-5pts.wt. toner B consisting of a thermoplastic resin and magnetic powder and having 2-8mum average particle size and 10<13>-10<16>OMEGA.cm electric resistance is used as a dry developer. The resins are selected so that reverse polarities are provided to the toners A, B by triboelectric charge. When development is carried out with a developing device composed of a magnet roll 13, a sleeve 12 and a magnetic blade 14, the toner A acts as a carrier, and the toner B gives an image with high resolution. |
