We applied the ESD technique to form an aligned LC layer with controlled pre-tilt angle. First, a horizontally aligned film was formed on the glass substrate by coating and rubbing. Then, a material promoting vertical alignment was sprayed using the ESD method. The aligned layer consisted of very fine domains mingled with horizontally and vertically aligned part. We were able to control the pre-tilt angle in a wide range by varying the amount of sprayed solution of the aligning material.

The electrospray deposition (ESD) method is an established film‐forming technique. To control the pretilt angle on films, we developed two novel ESD methods for spraying two kinds of solutions containing alignment materials. One method is a simultaneous spraying method, while the other is a time‐divided spraying method. When we used the simultaneous‐spraying ESD method, we observed numerous fine liquid crystal (LC) domains with a diameter of approximately 10 µm in the LC cell. These LC domains were substantially smaller than those of LCs fabricated using the conventional ESD method. However, the pretilt angle could not be controlled over a wide range because multiple parameters could not be simultaneously controlled to achieve a stable spray. Using the time‐division ESD method, we controlled the pretilt angle over a wide range from 5° to 40°, with tiny domains. As a demonstration, we fabricated a 270° super‐twisted nematic mode cell using this method.

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The sum of the flexo-coefficients (e 11 +e 33 ) was measured by the capacitance characteristic depending on the applied dc voltage in the HAN cell. The voltage for the minimum value of the capacitance was shifted by the influence of flexoelectric effect. One of the important problems for the evaluation for the flexo effect was the influence of impurity ions. Then, the chromatographic isolation phenomenon was used to separate impurity ions when the LC material was injected into the empty cell by the capillary action. The coefficient (e 11 +e 33 ) of ZLI-4792 was measured, and a value of 26.0 pC/m was obtained.

The electrospray deposition (ESD) method is an established film-forming technique.The pre-tilt angle was controlled by using the improved ESD method has been proposed by our previous report. In this paper, a novel torque balance method for measuring an improved azimuthal anchoring strength for the high pre-tilt angle was proposed. The pre-tilt angle was controlled and the azimuthal anchoring energy depended on the pre-tilt angle was evaluated. The azimuthal anchoring energy was obtained in the range from 10 −4 to 10 −5 J/m 2 depending on the pre-tilt angle.

Titania precursor films were electrosprayed on a quartz glass substrate, which was pre-modified with an ultra-thin film obtained by spin-coating a single-walled carbon nanotube (SWCNT) dispersed solution. The X-ray diffraction patterns of the thin films obtained by heat-treating the precursor films at 500 °C in air for 1 h indicated that the formed crystals were anatase. A new route to fabricate transparent thin films on the insulating substrate via electrospray deposition (ESD) was thus attained. The photoluminescence spectrum of the thin film showed a peak at 2.23 eV, assignable to the self-trapped exciton of anatase. The Raman spectrum of the thin film demonstrated that heat treatment is useful for removing SWCNTs. The thin film showed a water contact angle of 14 ± 2° even after being kept under dark conditions for 1 h, indicating a high level of hydrophilicity. Additionally, the thin film had a super-hydrophilic surface with a water contact angle of 1 ± 1° after ultraviolet light irradiation with an intensity of 4.5 mW cm–2 at 365 nm for 1 h. The importance of Ti3+ ions in the co-present amorphous phase, which was dominantly formed via the ESD process, for hydrophilicity was also clarified by means of X-ray photoelectron spectroscopy.

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