Development of the ink‐jet printing technology for 55‐inch 8K AMQLED display

In this paper, we obtained the optimal structure of QLED top‐emission spin‐coating device. Meanwhile, we also have successfully developed quantum dots and ZnO ink materials with high stability. With the top‐emission device structure and stable ink materials, we optimize the morphology of every film by controlling the drying process after ink‐jet printing. The emission area of united devices prepared by using the optimized ink‐jet printing process is equal to the designed area of pixels, with clear boundaries, uniform electroluminescent morphologies within a single sub‐pixel, and no significant difference in luminescence between pixels. Finally, we assembled and fabricated a 55‐in. 8K AMQLED display with a color gamut of 116% NTSC. The device structure of top‐emission and high stable ink materials are applied to the IJP device. The morphology of every film is achieved by using the optimized ink‐jet printing process. A 55‐in. 8K AMQLED display with a high resolution and wide color gamut is fabricated.