Inkjet Printing High Resolution Polydimethylsiloxane Dots Array

Inkjet printing polydimethylsiloxane (PDMS) has gain attention in the development of quantum dots light emitting diodes (QLEDs), color conversion layers, microfluid and flexible electronics due to its high transparency, good reflective index value, inflammable, biocompatible and flexile properties. While printing high resolution PDMS dots from dilute PDMS polymer solution is one of the main challenges for printing high quality PDMS functional films. This paper developed an PDMS ink to suppress the nonuniformities of PDMS dots at micrometer level. The developed PDMS ink was systematic tuned in the concentration of PDMS, in which ensuring wetting, and stimulating Marangoni flows that avoid the coffee-ring problem. The resulting uniform PDMS dots array was printed with diameter around 50 µm on the rigid substrate. And the array of closely spaced green quantum dots (QDs) mixing with PDMS ink was also printed on the rigid substrate uniformly. The green QDs PDMS film was also demonstrated on the rigid substrate uniformly at a resolution of 1693 dpi, which indicate the resulting of printing high quality color conversion films by combing PDMS ink with QDs.