• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.2
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• pp.157-162
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• 2000

The electro-optical characteristics of TN(twisted nematic)-LCD(liquid crystal display) with photo-dimerized on a PMCh(poly(4'methacryoyloxylchalcone)) surface using a new photo-dimerization method was studied. The excellent voltage-transmittance(V-T) curve of TN-LCD with photo-dimerized on a PNCh surface for 1 min. using a new photo-dimerization method was observed. Also, the voltage-hold-ing-ratio(VHR) of TN-LCD with photo-dimerized on a PMCh surface using a new photo-dimerization method is higher than that of conventional photo-dimerization method. Consequently, we suggest that the new photo-dimerization method. Consequently, we suggest that the new photo-dimerization method for LC aligning is the most promising rubbing-free techniques.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.7
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• pp.625-629
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• 2000

We synthesized a new copoly (PM4Ch-ChMA) copoly(poly(4-methacryloyloxy) chalcone-cholesteryl methacrylate) having chalconyl and cholesteryl moiety for homeotropic liquid crystal(LC) alignment. Pretilt angles of nematic(N) LC generated by linearly polarized UV exposure on the copolymer surfaces were investigated. Good thermal stabilities of the synthesized copolymer were obtained by TGA (Thermogravimetric Analysis) measurement. Pretilt angles of the NLC decreased with increasing UV exposure time on the copolymer surfaces. We consider that the pretilt angle of the NLC is attributed to increased chalcone by increased UV exposure time. High pretilt angle of the NLC is attributed to increased chalcone by increased UV exposure time. High pretilt angle of 81$^{\circ}$was observed after the UV exposure for 3 min.