• Pitch Variations in Cholesteric Liquid Crystal Film by Molecular Diffusion
  • Kwon Y, Lee W, Kim B, Kim I, Song K
  • 분자 확산에 의한 콜레스테릭 액정 필름의 피치 변화
  • 권영진, 이원주, 김범경, 김인선, 송기국
Abstract
Due to their periodic helical structure, cholesteric liquid crystals (CLC) have a unique ability to selectively reflect visible light. CLC films reflecting a broad wavelength band were prepared by inducing a pitch gradient in CLC layers through a diffusion of small molecules and through a thermal mixing of cyclic siloxane CLC molecules with different pitch lengths. Various pitch gradients in the CLC cell were observed using UV/Vis spectrometer and SEM technique.

콜레스테릭 액정은 주기적인 나선구조 때문에 빛을 선택적으로 반사하는 특성을 보이는데, 반사파장 대역이 넓은 cholesteric liquid crystal(CLC) 필름을 서로 다른 피치를 가지는 두 cyclic siloxane CLC의 열확산이나 저분자 물질에 의한 확산을 이용하여 제조하였다. 확산에 의한 CLC 액정 셀 내에 형성된 다양한 CLC 피치 분포를 SEM으로 관찰하였고, UV/Vis spectrometer를 이용하여 CLC 피치 분포 변화를 조사하였다.

Keywords: cholesteric liquid crystal; selective reflection; diffusion; pitch variation

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    ISSN 0379-153X(Print)
    ISSN 2234-8077(Online)
    Abbr. Polym. Korea
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This Article

  • 2006; 30(5): 422-425

    Published online Sep 25, 2006

  • Received on Jun 7, 2006
  • Accepted on Sep 21, 2006