Liquid Crystal Alignment Using Inkjet Printed Polymers
Abstract: The present invention relates to a non-rubbing alignment of liquid crystal made with an inkjet printing technique. Specifically, the invention provides aligning substrate for uniform alignment of liquid crystals (planar, tilt, and slightly tilted homeotropic) comprising organic films printed with an inkjet printer. In particular this method permits an easy axis of liquid crystal (that is the direction of preferable molecular orientation) confined to the direction of printed alignment film by the air-assisted buffing method. The pretilt angle can be controlled by mixture of PIs. The alignment film may be printed by applying a programmed printing or plurality of layers in sequence to induce a specific alignment structure, for example, a multi-domain aligned structure to enhance the homogeneous or self-compensate the retardation in a cell structure.
Applications: Using this technique, one can produce alignment layers for planar, tilt and homeotropic liquid crystal alignment, create polarizers, optical compensators, and integrated optical components as one may control the optical axis orientation of LC. In addition, the method enables one to produce an alignment layer for the liquid crystal devices on flexible substrate using a continuous process.
Advantages: This technique introduces a simple, fast, and cost effective way to create an anisotropic surface for liquid crystal alignment without the use of rubbing method. This method is easily adapted to a continuous fabrication process (roll-to-roll) where different optical components (color filters, optical compensators, etc.) can be manufactured on one fabrication line.
Inventors: Liang-Chy Chien and Jeoung Yeon Hwang
Gregory B. Wilson, Associate Vice President,
Economic Development and Strategic Partnerships