The Effects of Plasma Surface Treatment on Fluorosilicone Acrylate RGP Contact Lenses

불화규소 아크릴레이트 RGP 콘택트렌즈의 플라즈마 표면처리 효과

  • Received : 2010.05.28
  • Accepted : 2010.09.18
  • Published : 2010.09.30

Abstract

Purpose: Rigid gas permeable (RGP) contact lenses, based on fluorosilicone acrylate, were treated with plasma in air. Methods: The chemical compositions were analyzed by using X-ray photoelectron spectroscopy (XPS), the surface morphology and roughness of RGP contact lenses were observed by using atomic force microscopy (AFM), and the wettability changes were estimated by wetting angle measurement. Results: As the contact lenses were treated by the plasma, the F contents decreased significantly, and the O and Si contents increased on the surface. The number of oxygen-containing hydrophilic radicals (C-O and Si-O) increased greatly, the hydrophobic surface decreased, and the wetting angle increased. But the C-O bonds created with exchange of the fluorine did not increase a wettability. The surface compositions were not remarkably changed for the 6 months after plasma treatment, but the wetting angle increased again. Conclusions: It was considered that the improved wettability of the RGP contact lenses of high fluorine content after plasma treatment was affected by the activation of surface, the increase of Si-O, and the decrease of hydrophobic surface.

목적: 불화규소 아크릴레이트 RGP 콘택트렌즈(Boston EO, Boston XO)를 공기 중에서 플라즈마로 처리하여 표면의 성분, 형상, 습윤성의 변화를 연구하였다. 방법: 성분과 결합구조는 X-선광전자분광분석기(XPS), 형상과 거칠기는 원자현미경(AFM)으로 관찰하였으며, 습윤성의 변화는 접촉각을 측정하여 평가하였다. 결과: 플라즈마 처리에 의해 표면에서 불소는 크게 감소하고, 산소와 실리콘은 증가하였다. 산소를 포함하는 친수성기(C-O, Si-O)가 증가하고, 소수성인 표면이 감소하였으며, 접촉각이 증가하였다. 그러나 불소의 치환으로 생성된 C-O는 습윤성을 증진하지 않았다. 결과: 플라즈마 처리한 다음 6개월이 지나면 표면조성에는 큰 변화가 없으나, 접촉각이 다시 증가하였다. 결론: 불소의 함량이 높은 RGP 콘택트렌즈의 플라즈마 처리에 의한 습윤성 증가는 활성화된 표면과 Si-O의 증가, 소수성 표면의 감소에 의한 것으로 판단된다.

Keywords

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