Research on reducing electro-static discharge of tearing film of EPD

In this paper, we focused on reducing electrostatic discharge (ESD) of tearing film of Electro-phoretic display (EPD). The failure mechanism proves: ESD is generated when the film is torn, introduced through the surface ITO, and conducted to the weak points inside the pixel to breakdown, resulting in poor white spots of the module, with a failure rate as high as 43%. We mainly made improvements from external ESD sources and successfully developed the industry’s first anti-ESD film (TR522) on the surface of TFT substrates, which reduced ESD from 15 kV to 0.4 kV. Then we conducted DOE research on the characteristics of TR522 to improve the ESD immunity. The results showed that under such a tearing film environment: humidity ≥ 52.5%RH, temperature ≥ 24.6℃, ESD of tearing TR522 film: initial value ≤ 1 kV, value within 6 months ≤ 1.5 kV, no risk of failure.After TR522 was introduced into mass production, the defect rate was greatly reduced to 0%, and it was also horizontally promoted to other EPD, Mini, and Sensor products.