| 摘要 |
PURPOSE:To obtain stable dispersion of a finely granular org. pigment and to obtain high sensitivity and stable potential characteristic during durable use by specifying a specific viscosity for dispersion at a specific value. CONSTITUTION:The pigment dispesion liquid of which the specific viscosity for dispersion defined by the equation (specific viscosity for dispersion) = (the viscosity of the pigment dispersion liquid)/(the viscosity of the soln. excluding the pigment component) is in a 0.8-2.5 range is coated and dried to obtain a photoconductive compsn. Such specific viscosity for dispersion indicates the ratio at which the viscosity changes with the presence of the pigment particles mixedly in the pigment dispersion liquid. The specific viscosity for dispersion changes with the combination of the pigment, solvent and binder, the mixing ratio of the pigment and binder, the concn. of the solid component, etc. and the stability of the dispersion liquid is exceptionally good in the range of 0.8-2.5. The dispersion liquid having such specific viscosity for dispersion maintains the state having no flocculation and viscosity change for >=3 months in a model system of a coating machine shown in the figure after >=1 year of hermetic resting. An excellent photosensitive characteristic and charge characteristic during durable use are obtd. when such liquid is used for a photosensitive body. |
