| 摘要 |
PURPOSE:To obtain the electrostatic charge image developing toner which attains a stable electrostatic behavior and forms good images by using a magnetic material coated with a resin dispersed with a charge control agent. CONSTITUTION:A material having good compatibility with the binder resin is selected for the coating resin and the charge control agent which is the same as the charge control agent to be dispersed in the binder resin is used for the charge control agent. Kneading using means, such as hot rolls, is adopted as the dispersing method in the same manner as the method for dispersing the charge control agent into the binder resin. The binder resin is ground and is dissolved in a suitable amt. of a toluene solvent to prepare a coating resin soln. The magnetic material particles are under coated with a silane coupling agent or titanium coupling agent and the magnetic material is coated with the resin soln. by a spray drying method. The treating amt. of this resin soln. is 0.1 to 10 pts. wt. per 100 pts. wt. magnetic material. The toner attains the uniform electrostatic charge in developed parts and the images free from degradation in image quality, such as fogging and stripes, are obtd. if the magnetic material constituted in such a manner is used. |
