Fumio Moriwaki

5.1: Fluorescent RGB OLEDs with High Performance

We developed highly efficient fluorescent dopants for full-color OLEDs. For blue, green and red OLEDs, current efficiencies of 8.7cd/A, 20.5 cd/A and 11.4 cd/A at 10mA/cm2 were achieved, respectively. Lifetime of the blue device was estimated to be 23,000hours at an initial luminance of 1,000 cd/m2. Moreover, long lifetime of 100,000 hours was estimated in the green and red devices. By the use of these dopants, we expect that a full-color OLED display with the lifetime of 18,000 hours at a white luminance of 300 cd/m2 can be achieved.

Ferroelectric liquid crystalline polyoxyethylenes with etheric-oxygen-containing spacers

Abstract Ferroelecmc liquid crystalline polyoxyethylenes are synthesized. Each side chain consists of etheric-oxygen-containing methylene spacer, biphenyl or biphenyl benzoate core and 2-methylbutoxycarbonyl chiral end group. The addition of the first oxygen atom, counted from the main chain, to the methylene spacer broadens the SmC* temperature range and shortens the electro-optical response time. The shorter response time suggests that the additional carbon-oxygen linkages promote the decoupling between the main chain and the side chains. The addition of the second and third oxygen atoms, counted from the main chain, as oxyethylene units, lowers the degree of polymerization and does not shorten the response time further.

4.3: Novel Flexible Display using Ferroelectric Liquid‐Crystalline Polymer and Plastic Film Substrates

A novel flexible LCD has been developed by combining plastic film substrates with a FLCP mixture. Its optical response time has been improved by using a newly developed FLC polymer, particular polysiloxane typed structure. Good toughness against external shock has been achieved by arranging columns of UV-cure resin in the FLC layer. Manufacturing process of this LCD is simple and very unique. Coating the FLCP mixture on a plastic substrate and aligning molecules by bending method are used in the process. This LCD enables to realize a lightweight and flexible document reader called electric-paper by means of good memory effect and good mechanical durability.