21.4: Development of Low-Retardation TAC FILM for Color-Shift Improvement in LCDs

Abstract

We have developed the birefringence control technology of TAC film by organic additives. By using this technology, for the first time in the world, we could industrialize new TAC film whose Re value (in-plane retardation) and Rth value (out-of-plane retardation) are both nearly zero. This TAC film has very interesting feature that Rth variation is very small even if stretch force is loaded. Therefore, it is proper to make polarizer and attach the polarizer on LCD panel because accidental Rth doesn't rise in these processes. Also this TAC film can reduce the color shift at oblique incidence for especially IPS mode LCDs.