In the dry type developer for electrostatic charge image development which contains with the dry type

摘要

PROBLEM TO BE SOLVED: To provide an electrostatic charge image developing dry developer having the toner particles good in fluidity and well chargeable from the start of development unchanged in the charge amount of the toner particles even in the case of developing a large number of images and to provide the developing method by using this dry developer. SOLUTION: This electrostatic charge image developing dry developer comprises (a) the toner particles containing a binder resin and a colorant, (b) fine amorphous silicon aluminum cooxide particles treated to enhance hydrophobicness comprising a 55-75 weight % Al2O3 and a 45-25 weight % SiO2 or fine amorphous silicon titanium cooxide treated to enhance hydrophobicness comprising a 50-80 weight % TiO2 and a 50-20 weight % SiO2, and (c) when needed, a mixture of carrier particles. The chargeable amount of the toner particles can be controlled by changing a rate of Al2O3 or TiO2 to SiO2 of the cooxide of the developer, and the fine cooxide particles of the optimum composition in accordance with a copying machine or the toner to be used are selected.