Based Pdlc Black And White Flexible Display Technology

In this paper, Polymerization induced phase separation (PIPS) has been applied to prepare Polymer Dispersed Liquid Crystal (PDLC) films, and the effect of four bisphenol-a acrylate monomers, 1H,1H,7H-Dodecafluoroheptyl methacrylate(F) and Isooctyl methacrylate(E)etc on electric-optical properties and morphologies of LC droplets have been investigated. Many factors influencing the Polymerization induced phase-separation, which include monomer concentration,thickness,cure temperature,ultraviolet intensity, surface rubbing effect and so on, have been mainly investigated. And we also have researched the effect of these factors on electro-optical properties, morphologies of LC droplets, viewing angle effect, and response time etc of PDLC films.Morphologies of LC droplets in flexible PDLC films have been detected and verified by SEM (Scan Electron Microscope) and 6811LN-CVC (Colour Video Camera). The surface rubbing effect of ITO-PET can make LC droplets become more homogeneous and smaller, and induce LC droplets to exhibit in the rubbing direction uniformly. Meanwhile, it can be found the fact that the surface rubbing effect of substrate is propitious to decline threshold voltage Vth, saturation driving voltage Vdr and response time (i.e.the raising timeτraise and the decaying timeτdown) and improve contrast ratio CR.By means of optimization, a 7μm-thickness PDLC film provided with Vth=0.18v?μm-1, Vdr=0.40v?μm-1, viewing angle±56o(T>50%),τraise=52.0ms,τdown=28.0ms and CR=7.34 has been prepared successfully basing on ITO-glass substrate; Meanwhile, a 13μm-thickness flexible PDLC film possessing with Vth=0.32 v?μm-1, Vdr=0.78v?μm-1, viewing angle±50o(T>50%),τraise=44.8ms,τdown=38.8ms and CR=35.96, has also been prepared successfully basing on ITO-PET flexible substrate. Meanwhile, the principle of black and white display of flexible PDLC films is studied basing on the orthogonal polarizer in this text. And we have researched the effect of film thickness and monomer concentration on the electro-optical properties of PDLC films upon the condition of orthogonal polarizer, and the black and white display of a PDLC film, which possesses the electro-optical performance parameters of CR=16.80, Vth=0.09v?μm-1, Vdr=0.36v?μm-1, viewing angle±13o(CR≥5),τdown=23.6ms andτraise=84.8ms, has been realized.Finally, MMA/BMA, MMA/BzMA and MMA/ST/BzMA, which can be prepared zero-birefringence optics resin, have been studied tentatively. Thereinto, the optics properties of PMMA/PS/PBzMA (i.e.MMA:ST=95:5,(MMA/ST):BzMA=68:32) is relatively excellent. And the birefringenceΔn (i.e.Pull-Loll ratio L/Lo=3), transmission (i.e.The scale of light wavelength is 420-800nm) and glass translate temperature of the optics resin are approximately 5.50×10-6, 90-95.6% and 91.9℃respectively.