Triboelectric Charging between Display Glass Panels and Dissipative/Insulative Rollers

The underlying cause of most electrostatic discharge is tribocharging. Thus, understanding tribocharging is essential to assess the likelihood of damages as they might occur in the production of liquid crystal display (LCD) screens. In this paper, a study of triboelectric charge build-up between the glass and rollers during the glass transfer process in display panel manufacturing is presented. A roller conveyor system was fabricated and two types of rollers materials, insulative and dissipative, with radii of 30 and 90 mm, were considered. To measure the triboelectric charge of the glass, a Faraday cup with an elevator system was mounted on the apparatus. Various parameters including transfer velocity, acceleration/deceleration, and relative humidity were investigated. For instance, it is observed that the average saturated charge density on the glass is 0.324 nC/cm² after 320-m displacements if it transfers by small dissipative rollers with condition of 200 mm/s and 200 mm/s². In addition, a comprehensive study of the surface potential distribution on the glass and rollers by utilizing a two-dimensional automated scanner is presented. The experiments pointed out that the amount of charge accumulated on the glass for the dissipative rollers saturated faster with a smaller value than the insulative rollers.