Study on Morphology of Quantum Dots Films Prepared by Inkjet Printing

In this research, the quantum dot films, which were improved by solvent selecting and ratio adjusting, controlling the droplet spacing and inkjet voltage for the coffee ring suppression, were fabricated using inkjet printing technology. As a result, the coffee ring was eliminated by mixing three organic solvents and adjusting the ratios between three solvents with different boiling points. Therefore, the coffee ring phenomenon was reduced when the volume ratio of cyclohexylbenzene/butyl benzoate/n-octane in the QD ink was 7: 3: 5. The uniformity and completeness of the film surface were developed by controlling the droplet spacing. When the droplet spacing was 60 µm, the film surface was more uniform and complete. To improve the film surface, the control of the inkjet voltage regulated the droplet injection and droplet shape. When the inkjet voltage was 15 V, not only was the inkjet effect more stable, but the ejected dropleshape was complete. The research of quantum dot films provides technical support for the preparation of QLED and QLED displays.