Analysis of Noncontact Squeegeeing Device for Liquid Toner Electrophotography

A noncontact squeegeeing device is used just after the development process in a liquid toner electrophotographic printing system. By using capillary forces, this device removes almost all of the surplus liquid adhering to the photoreceptor surface. Though the device has a simple structure and has even been used in actual systems, there is not much information regarding the mechanism of the device available in the literature, and the mechanism does not seem to have been theoretically analyzed. In this paper, some equations are derived from the lubrication approximation theory based on the condition that total liquid flow is zero. The calculation results obtained using these equations show good agreement with the experimental results for the variation of the characteristics of the squeegeeing efficiency with the circumferential surface velocities of rollers. The proposed equations make the calculation of the squeegeeing characteristics easy and thus facilitate improvement of the device and further development of the system.