Preparation of Hard Coating Solutions with High Refractive Index for Polycarbonate Sheet by the Sol-Gel Method

Sol-Gel 법에 의한 Polycarbonate 시트에 적용 가능한 고굴절률을 보이는 하드코팅 용액의 제조

  • Cheong, Il Yeop (Department of Chemical and Biochemical Engineering, Konyang University) ;
  • Cho, Kyung In (Department of Chemical and Biochemical Engineering, Konyang University) ;
  • Cheong, Sang Hyuk (Department of Chemical and Biochemical Engineering, Konyang University) ;
  • Park, Hyo Nam (Department of Chemical and Biochemical Engineering, Konyang University) ;
  • Song, Ki Chang (Department of Chemical and Biochemical Engineering, Konyang University)
  • 정일엽 (건양대학교 화공생명학과) ;
  • 조경인 (건양대학교 화공생명학과) ;
  • 정상혁 (건양대학교 화공생명학과) ;
  • 박효남 (건양대학교 화공생명학과) ;
  • 송기창 (건양대학교 화공생명학과)
  • Received : 2007.03.22
  • Accepted : 2007.03.31
  • Published : 2007.08.31

Abstract

In order to overcome the problem of poor hardness of transparent polycarbonate (PC) sheets, organic-inorganic hybrid hard coating solutions, which show a high refractive index above 1.58, were made by the sol-gel method. These hybrid coating solutions were obtained from mixture of titanium tetraisopropoxide (TTIP), and (3-glycidoxypropyl)trimethoxysilane (GPTMS). The PC sheets were spin-coated, and cured at $120^{\circ}C$ for 2 hr. Change of refractive index in the range of 1.53-1.61 was obtained by varying the GPTMS content. The refractive index of the coated film decreased with increasing the GPTMS content, while the pencil hardness of the coated film was found to increase with increasing the GPTMS content.

투명 polycarbonate(PC) 시트의 낮은 표면강도 문제를 극복하기 위해, 고굴절률을 보이는 유-무기 혼성 하드코팅 용액을 Sol-Gel 법을 이용하여 제조하였다. 코팅용액은 무기물 티타니아의 전구체인 TTIP(titanium tetraisopropoxide)에 유기물을 함유한 화합물인 GPTMS[(3-glycidoxypropyl) trimethoxysilane]를 첨가하여 제조하였다. 그 후 기재인 PC 시트에 스핀 코팅시키고, 열 경화 시켜 고굴절률을 보이는 하드코팅 필름을 제조 하였다. 코팅 용액 중의 GPTMS 함유량을 변화시킴에 의해 1.53-1.61의 굴절률을 갖는 코팅 막의 제조가 가능하였다. GPTMS의 첨가량이 증가할수록 코팅막의 굴절률은 감소하였으나, 연필경도는 증가하였다.

Keywords

Acknowledgement

Supported by : 한국산업기술재단

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