Novel blue light-emitting polymers for PLED

Shuji Doi; Takeshi Yamada; Yoshiaki Tsubata; Masato Ueda

doi:10.1117/12.563805

10 November 2004 Novel blue light-emitting polymers for PLED

Shuji Doi, Takeshi Yamada, Yoshiaki Tsubata, Masato Ueda

Proceedings Volume 5519, Organic Light-Emitting Materials and Devices VIII; (2004) https://doi.org/10.1117/12.563805
Event: Optical Science and Technology, the SPIE 49th Annual Meeting, 2004, Denver, Colorado, United States

Abstract

We have been researching blue-emitting polymers and developed some novel polymers with blue fluorescence, which are not fluorene copolymers. Our previous works showed the dependence of EL efficiency on molecular weight of poly(p-phenylene vinylene) derivatives. We concluded that polymers must be synthesized by the method which gave larger molecular weight in order to achieve higher performance. Firstly, we modified the synthetic method of polyarylenes and confirm that Mw of ca.1,000 to over 1,000,000 is obtainable depending on the condition. Polymers having moderately large Mw showed good solubility in solvents and film-forming properties. PLEDs using these polymers had longer lifetime as well as higher EL efficiency. Secondly, we understood the importance of charge balance between electrons and holes, by using polyfluorene derivatives as model polymers. We measured electron, hole and total currents by electron-only, hole-only and usual bipolar devices respectively. We found out that the hole mobility could be changed from 10^-7cm²/Vs to 10^-3cm²/Vs depending on the content of hole transporting units. In addition, electron injection from a cathode seemed to be assisted by trapped holes. We utilized these results in order to design our blue polymers. Finally, we obtained a new blue-emitting polymer, which showed longer device lifetime among non-fluorene polymers.

Citation Download Citation

Shuji Doi, Takeshi Yamada, Yoshiaki Tsubata, and Masato Ueda "Novel blue light-emitting polymers for PLED", Proc. SPIE 5519, Organic Light-Emitting Materials and Devices VIII, (10 November 2004); https://doi.org/10.1117/12.563805

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available