| 摘要 |
PURPOSE:To obtain superior thin line reproducibility and superior resolution by using a mixture of positively chargeable magnetic toner specified in particle diameter, fine resin particles specified in triboelectrification amount and primary average particle diameter, and a fine silica powder specified in specific surface area. CONSTITUTION:The magnetic toner comprises a binder resin and a magnetic powder and this toner contains particles of <=5mum particle diameter by 12-60 number % of the total particles, ones of 8-12.7mum particle diameter by 1-33 number % of the total particles, and ones of >=16mum particle diameter by <=2.0 volume % of the total particles, and it has a volume average particle diameter of 4-10mum and it is positively chargeable. The resin particles are triboelectrificated in an amount of +50 to -600muC/g against an iron powder, and have a primary average particle diameter of 0.01-1.0mum. The fine silica powder has a specific surface area of >=30m<2>/g. The developer contains 100pts. wt. of the toner, 0.1-5pts.wt. of the resin particles, and 0.01-10pts.wt. of the silica powder. |
