Effect of Stabilizers on Performance of Electroluminescence Display Device

안정화제가 무기 전계발광 디스플레이 소자 성능에 미치는 영향

  • Shin, DongHyuk (Department of Physics, Dongguk Univ.) ;
  • Lim, JongChoo (Department of Chemical and Biochemical Engineering, Dongguk Univ.)
  • 신동혁 (동국대학교 물리학과) ;
  • 임종주 (동국대학교 생명.화학공학과)
  • Received : 2007.03.29
  • Accepted : 2007.04.07
  • Published : 2007.08.31

Abstract

The stability of paste solutions for electroluminescence display(ELD) device was found to be greatly affected by kind and dosage of a stabilizer used. The stabilizer Disperbyk-180 showed the best stability performance against phosphor paste solutions among the stabilizers used during this study. The phosphor paste solutions remained stable over 90 days with a wide range of added amounts of Disperbyk-180. Based on the above results, screen printing test was performed. The addition of Disperbyk-180 into phosphor and dielectric paste solutions produced improved qualities such as no phase separation, no bubble generation and no significant viscosity change during printing process. Especially for the phosphor paste solution, both uniformity and brightness were significantly improved and the excellent adhesion onto the ITO film was found. The ELD device fabricated using the above same paste solutions showed brightness of $57.6cd/m^2$ at 100V and 400 Hz. The half lifetime of ELD device was measured as 1,250 hours and almost the same value observed with imported commercial paste solutions.

전계발광(EL) 소자 제조용 액상 페이스트 용액의 안정성은 사용한 안정화제의 종류 및 첨가량에 크게 영향을 받았으며, 본 실험에서 사용한 안정화제 중에서 Disperbyk-180이 형광체 액상 페이스트에 대하여 넓은 첨가량 범위에서 90일 이상의 안정성을 보였다. 안정화제 Disperbyk-180을 형광체 및 유전체 페이스트 용액에 첨가하여 인쇄 실험을 수행한 결과, 층분리 현상은 일어나지 않았으며, 균일도는 기존 사용 페이스트 보다 우수한 것으로 나타났고 인쇄 시 기포 발생과 점도 변화가 매우 작았다. 특히 형광체 페이스트의 경우 균일성과 휘도가 기존의 페이스트에 비하여 상당히 향상되었으며, ITO 기판과의 접착성도 우수하였다. 안정화제 Disperbyk-180이 첨가된 페이스트를 사용하여 제조한 EL 소자는 100 V, 400 Hz에서 $57.6cd/m^2$의 휘도를 나타내었으며, 주파수 변화에 따라서 급격한 휘도 변화는 나타내지 않았다. 또한 EL 소자의 수명을 측정한 결과 반감기는 1,250시간으로 외국에서 수입되어 시판되고 있는 페이스트를 사용한 경우와 유사한 수명을 나타내었다.

Keywords

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