Electrostatic damage by detachment of protective film on polarizer

Abstract

LCD manufacturing processes are often exposed to the electrostatic hazards due to going through various optic film processes. In this paper, we report the electrostatic discharge failure that occurred during the detachment process of protective film to attach consecutive one on a panel. The effects of modified surface treatment on an adhesive layer of the protective film and the entry sequence of the stage to move the following process in the peeling process of protective film were analyzed. The difference of the respective surface properties of the protective film was investigated using scanning electron microscope (SEM) and the electrostatic voltage measurements during a peeling process. The surface characterization of the film, when it is being rubbed and separated from main film, affects the amount and variation of electrostatic charge generation. Modified surface treatment of a protective film showed significant effect to reduce the failure rate and the maximum friction charge. And it was found that changing solely the entry sequence of the following stage with the modified protective film has a residual electrostatic problem. As a result, a main cause of the failure is considered that the variation of the capacitance between the panel and the stage when charges are generated during a peeling process. (C) 2014 Elsevier B.V. All rights reserved.