| 摘要 |
PURPOSE:To obtain a toner having a long life, superior chargeability, shelf stability and high-speed fixability under low pressure, by dropping and dispersing a mixture contg. a polyolefin and a surfactant in a heated basic aqueous soln. to form spherical fine particles. CONSTITUTION:A polyolefin such as polyethylene with >=0.94g/cm<3> density and <=600cps melt viscosity at 140 deg.C, polyethylene with >=0.94g/cm<3> density and <=150cps viscosity, polyethylene with 5-30melt index or a modified polyolefin with 1-150 acid value is mixed with a surfactant and melted by heating. A coloring agent such as carbon black and magnetic fine particles may be added to the mixture. The melt is dropped in a heated basic aqueous soln. of KOH or the like and stirred to form fine toner particles dispersed in the soln. The particles are separated by filtration, washed with methanol, centrifugally separated, and dried under vaccum to obtan a spherical toner in a high yield. The grain size distribution of the toner is easily controlled, and the toner has superior image forming properties. |
