Abstract: The present invention provides a heat transfer process and a heat transfer ink sheet, where a letter or image or both is recorded by selectively heating a heat transfer ink sheet having ink layer regions each containing a sublimable or vaporizable dye by heating by a thermal head controlled by a controlling means, thereby selectively heat transferring the sublimated or vaporized dyes onto a recording sheet, and is characterized by heat transferring a precoating layer for receiving the dyes from the ink sheet onto the recording sheet before the heat transfer recording, and then pressing the ink sheet on the transferred precoating layer on the recording sheet and heating the ink sheet by the thermal head, thereby sublimating or vaporizing the dyes from the respective ink layers onto the precoating layer and forming the letter or image or both on the recording sheet.

Abstract: When the reflection density of the colorants of an ink layer is 1.3 after transfer onto a recording paper, a reflectance of yellow colorant lies in between two diagrams (D.sub.1, D.sub.2) shown in FIG. 1, a reflectance of magenta colorant lies in between two diagrams (D.sub.3, D.sub.4) shown in FIG. 2, and a reflectance of cyan colorant lies in between two diagrams (D.sub.5, D.sub.6) shown in FIG. 3. A color ink sheet realizes an excellent hue, a high luminance factor and high chroma. A wide color specification range and clear image having a high color reproducibility is obtained.

Abstract: A colorless liquid crystalline compound having at least one 6-membered ring and non-cyclic end groups in the molecular skeleton, said 6-membered ring containing two or more carbon atoms, at least one of which is directly bonded to a methylene group of a non-cyclic group having an alkoxy group at another end has a wide mesomorphic range. When said colorless liquid crystalline compound is mixed with a liquid crystal composition, the resulting mixture also has an enlarged mesomorphic range and in almost all cases has a reduced viscosity.

Abstract: A thermal transfer recording sheet comprising a substrate and ink layer formed thereon containing one or more sublimable dyes and a high-molecular-weight polyamide obtained from dimer acids as a binder is good in adherence of the ink layer to the substrate, and thermal transfer properties to give clear color hard copies.

Abstract: An optical apparatus comprises an optical device having an optically functional material sandwiched between a pair of substrates with electrodes formed on opposing surfaces. The optically functional material has such a characteristic that intensity of light issuing from the optical device changes asymmetrically in response to inversion of the polarity of an applied external field. Pulse voltages of one polarity for determining the intensity of the issuing light and pulse voltages of an opposite polarity are applied from a source at a predetermined period so that an average voltage is zeroed within the predetermied period. The issuing light intensity under the application of the pulse voltages of one polarity and the issuing light intensity under the application of the other pulse voltages are selected or changed by a switching unit.

Abstract: The liquid crystal compound of this invention is characterized by having the general formula.

Abstract: The present invention is characterized by a smectic liquid crystal compound represented by the following formula: ##STR1## wherein R is selected from alkyl and alkoxy groups; X from ##STR2## m and n are natural numbers; and R* is an optically active group containing an asymmetric carbon atom, and a liquid crystal composition containing said compound as a component. This compound is excellent in optical stability and high-speed response.

Abstract: A colorless liquid crystalline compound having at least one 6-membered ring and non-cyclic end groups in the molecular skelton, said 6-membered containing two or more carbon atoms, at least one of which is directly bonded to a methylene group of a non-cyclic group having an alkoxy group at another end has a wide mesomorphic range. When said colorless liquid crystalline compound is mixed with a liquid crystal composition, the resulting mixture also has an enlarge mesomorphic range and in almost all cases has a reduced viscosity.