Journal of the Semiconductor & Display Technology (반도체디스플레이기술학회지)

The Korean Society Of Semiconductor & Display Technology (한국반도체디스플레이기술학회)
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Optimization of Optical Performance of Colorless and Transparent Polyimide Film for Flexible Display using Design of Experiment

실험계획법을 이용한 유연 디스플레이용 무색 투명 폴리이미드 필름의 광학 성능 최적화

  • Jo, Dawoon (Department of Mechanical System Engineering, Kumoh National Institute of Technology) ;
  • Yu, Yeon-Soo (Department of Mechanical System Engineering, Kumoh National Institute of Technology) ;
  • Nam, Hee-Eun (Department of Mechanical System Engineering, Kumoh National Institute of Technology) ;
  • Chang, Jin-Hae (Institute of Carbon Technology, Jeonju University) ;
  • Oh, Chung-Seog (Department of Mechanical System Engineering, Kumoh National Institute of Technology)
  • 조다운 (금오공과대학교 기계시스템공학과) ;
  • 유연수 (금오공과대학교 기계시스템공학과) ;
  • 남희은 (금오공과대학교 기계시스템공학과) ;
  • 장진해 (전주대학교 탄소기술연구소) ;
  • 오충석 (금오공과대학교 기계시스템공학과)
  • Received : 2022.02.26
  • Accepted : 2022.03.25
  • Published : 2022.03.31
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Abstract

As various flexible display products are released, the demand for high-performance colorless and transparent polyimide (CPI) film is continuously increasing. The primary purpose of this study is to establish a systematic procedure for optimizing the optical performance of CPI films by applying the response surface method. After selecting three key factors (monomer type, stirring time for varnish synthesis, and maximum temperature of vacuum furnace for film production) affecting optical performance based on experiences and references, CPI films were manufactured according to the experimental sequence designed by the central composite design, and then the yellowness index (YI) and optical transmittance (Tr) of the films were measured. When producing a CPI film by pouring varnish into a petri dish, the change in optical properties according to thickness should be considered, and there was a meaningful linear relationship between YI and Tr. The species of monomer and the maximum temperature were the critical factors that had an influence on YI and Tr, respectively. It is expected that the procedure proposed in this study can serve as a starting point for CPI film optimization studies considering the other factors that were not considered and responses such as thermal properties.

Keywords

Acknowledgement

이 연구는 2020년 국립대학 육성사업비로 지원되었음.

References

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