60‐3: Functional Study of High‐Transparency Encapsulation Films Based on Inkjet Printing Technology

Display devices are more and more widely used in mobile devices and wearable devices, which put forward higher lightweight requirements for display devices. The thin film encapsulation (TFE) technology for display panels has emerged. Through the combination of inorganic and organic films, the thin film encapsulation films can provide 10‐6 levels of water vapor barrier ability at the thickness of micrometers, helping the display devices to realize the dual role of lightweight and long lifetime. Organic encapsulation layers prepared by inkjet printing technique with acrylate composition and epoxy composition are commonly used materials in mass production process, which can effectively improve the barrier properties and softness of thin film encapsulation. However, to prepare organic encapsulation films in line with mass production process, it is necessary to achieve high light transmittance, high aging resistance, ultra‐fast curing rate, low volatile level and other functions. In this paper, from the materials perspective of inkjet printing ink, we’ve studied how to realize the multifunctionality of organic encapsulation films through the combination of ink components and the configuration of functional groups, so as to provide reference for the downstream device preparation of organic encapsulation films. By reducing the content of chromogenesis impurities, both acrylic and epoxy based films can achieve high light transmittance (see Fig.8) using inkjet printing film formation method, and the transmittance of visible light (400nm‐800nm) can reach more than 98%. Controlling curing degree above 95% can result in good aging performance (see Table 5&6), and a very low volatile level. (see Fig. 3).