New alignment layer free vertical alignment (VA) liquid crystal device is proposed. In the device, the nanoparticles, reactive mesogen, and LC mixture are mixed together and filled into the cell with fishbone electrode structure. Through diffusion process, the particles moved to both surfaces of substrates, generating vertical alignment and then UV is exposed while applying proper voltage to the cell. Then, LC director is stabilized to form multi‐domain by polymerization of reactive mesogen. Consequently, the device shows, wide‐viewing‐angle and fast response time although conventional polymer layer is not used.

Abstract— By introducing polyhedral oligomeric silsesquioxane (POSS) nanoparticles along with a controlled amount of UV‐curable reactive mesogen (RM) into a liquid‐crystalline (LC) medium, a multi‐domain vertical‐alignment LC device was successfully demonstrated. The device, possessing a vertically aligned LC director in four different azimuthal directions, exhibited a fast response time and wide‐viewing‐angle characteristics, in the absence of conventional polymer‐type vertical‐alignment layers. Electro‐optic characteristics of the fabricated device, before and after UV curing of the cell, were studied. The surface morphology of the substrate surfaces were analyzed by using field‐emission scanning electron microscopy (FESEM). The experimental results show that the technology will possibly be applicable to cost‐effective vertical‐alignment liquid‐crystal devices and is suitable for green‐technology liquid‐crystal displays.

A multi-domain vertical alignment device using a new method for forming protrusions is proposed. In the device, the photo-sensitive ink was printed with line shape forming protrusions on the substrates. Then the cell was assembled with crossed-line shaped protrusions on top and bottom substrates. Owing to symmetrically positioned protrusions, the vertically aligned LCs form multidomain in on state and with the help of surface polymerstabilization technique, the response time is greatly improved. Consequently, the proposed device using protrusion by any printing method shows excellent performance such as wideviewing-angle and fast response time without conventional photolithography process.

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