In order to design the toner particles of thermoplastic resin coated with charge countrol agents (CCA), a dry coating method was applied to its complex formation. Experiments were carried out with a high speed-high shear mill by changing operating conditions. The compound states of the particles designed were evaluated by the measurement of lightness. The triboelectricity of the particles obtained were investigated by the Blow-off measurement of triboelectric charge in the case of mixing with magnetic material particles (Carrier).
The results obtained are summarized as follows:
1) It was found that the triboelectric charge of composite particles is maximum against operation time under each operating condition. The maximum was obtained at a shorter operation time under the condition of higher rotating speed of the casing and narrower gap between the inner piece and the casing.
2) It was possible to represent a curve of the triboelectric charge vs. energy consumption despite various operating conditions. Then it was apparent that the triboelectric charge of the CCA-coated composite particles makes a maximum against energy consumption, and the maximum was obtained at about 2×106J/kg.
Based on these facts, it is possible to design the CCA-coated composite particles which have excellent triboelectricity by the dry coating method, and to determine the optimum operating conditions.
