摘要:
A thermochromic effect pigment comprising a thermochromic liquid crystal material encapsulated with a polymer and coated with one or more inorganic metal oxides or nearly insoluble metal salts selected from Al.sub.2 O.sub.3, SnO.sub.2, ZrO.sub.2, TiO.sub.2, CaO, SiO.sub.2, ZnO, MgO or BaSO.sub.4. The pigment is stable in solvent-based formulations and can be used as a colorant in the form of an aqueous suspension or as a powder in lacquer compositions, plastic compositions, dyed filter compositions, dyed glass compositions, dyed cosmetic compositions, printing ink compositions, and in hair coloring agents.
摘要:
Liquid crystal phases containing components of the formulae I and III have an acceptable combination of threshold steepness, viewing angle and temperature dependence at a low threshold voltage.
摘要:
The present invention relates to an improved sensor arrangement, a system and method for determining the rate of ice formation and how close conditions are to those at which ice will form on a surface, and to an improved sensor arrangement for use therein. The sensor arrangement comprises a means (11,12,14) for measuring the thermal lag, heating and cooling of a thermally conductive element, which is comprised of a first and second surface (15a, 15b), said first surface exposed to the environment, wherein the surface area of said first surface is smaller than the second surface. The step of ice detection may be performed by either a passive measuring system wherein the latent heat of ice formation is measured via the temperature differential across a Peltier element. In an alternative arrangement the detector may preferably be an active system comprising heating or cooling the Peltier device and, whilst such heating or cooling is being conducted, also measuring the temperature of the exposed outer first surface using a separate temperature detector.
摘要:
A method of fabricating an electrode structure for a multilayer semiconductor device comprising a semiconductor layer having a first electrode layer in contact therewith and a second electrode layer separated there-from by a dielectric layer (8), the method comprising the steps of; applying a patterning material (20) only to selected areas of a support layer within the device so as to define the arrangement of the first electrode layer thereon; applying to the support layer a catalyst (24) adapted to be responsive to the patterning material (20); applying a conductive material (26) to the support layer so as to form the first electrode layer thereon; wherein the support layer, the patterning material (20) and the catalyst (24) cooperate such that the conductive material (26) is only deposited on the selected areas of the support layer to which the catalyst (24) has been applied. An thin film transistor (2) having a gate insulator layer (8) comprising an epoxide material.
摘要:
A liquid crystal device is provided with a pair of substrates (12, 16) containing a liquid crystal material (22). A wall structure comprising, for example, a plurality of walls (14) is provided between the two substrates. The wall structure provides mechanical strength to the device and resistance to flow of liquid crystal material which can cause deterioration in the device performance. The walls may extend in two mutually different directions (FIG. 8, 40) to provide mechanical strength and resistance to flow in two directions while the device can still be readily filled. The device is particularly applicable to a ferroelectric liquid crystal device.
摘要:
A bistable display device comprises two cell walls enclosing a sheet having a plurality of cavities each containing a rotatable bicoloured sphere within a liquid crystal material carrier (15), and electrodes for applying an electrical field. The spheres and cavities are provided with a surface alignment which imposes a substantially unidirectional director alignment on the liquid crystal material in contact with them. The elastic distortion free energy of the liquid crystal material in each cavity is arranged to be zero when the preferred direction of the suspended spheres coincides with that of the surrounding cavity, e.g. black upwards. It is also zero when the sphere is rotated through 180° to present its opposite hemisphere which has a contrasting optical appearance, e.g. black downwards. Between these two states, there is an energetic barrier determined by the elastic constants of the liquid crystal which provides both a threshold for switching and improved bistability. During production of the sheet, alignment may be enhanced by application of an electric or magnetic field during curing or cooling of the components. The display may be addressed in a known multiplexed manner.
摘要:
Liquid crystal devices are formed by a layer of a liquid crystal material enclosed between two cell walls, both carrying electrode structures, and one or both walls treated to align molecules of the liquid crystal material. Most alignment treatment give alignment and surface pretilt with a strong azimuthal and zenithal anchoring energy to contacting liquid crystal molecules. The invention reduces at least one of the azimuthal zenithal or translational anchoring energy to improve switching characteristics and optical performance by allowing movement of liquid crystal molecules at or close to the cell wall. The reduction of anchoring energy may be achieved by an oligomer or short chain polymer which is either spread on the surface or added to the liquid crystal material. The size of oligomer or short chain polymer is low enough that it does not appreciably phase separate from the liquid crystal material. The polymer layer has the characteristics of having imperfect solubility in the liquid crystal material used in the device, of having a physical affinity for the surface of the substrate, and of retaining a substantially liquid like surface at the polymer/liquid crystal interface. The polymer may be formed by polymerisation of reactive low molecular weight materials in solution in the liquid crystal fluid. The resulting solution or dispersion of polymer in liquid crystal is then filled into the cell, and the polymer is allowed to coat the substrate surfaces.
摘要:
A fluorinated phenyl compound having the general formula [1]: wherein each of s, v and x=0 or 1, each of t and u=1, 2 or 3, and each of y and z=0, 1 or 2; A, B and C are independently selected from conjugated cyclic moieties including heterorings and fused rings; R1 and R3 may be independently cyano, or (C1-C12)alkyl, (C1-C12)alkoxy, (C1-C11) alkoxycarbonyl or (C1-C11)alkylcarbonyloxy which may be fluoro- and/or cyano-substituted; R2=H or F; R4=H or F; and R5=H or F. Such compounds have high transverse dipole moments and are potentially useful in liquid crystal compositions and in devices including same.
摘要:
A liquid crystal device is provided with a pair of substrates (12, 16) containing a liquid crystal material (22). A wall structure comprising, for example, a plurality of walls (14) is provided between the two substrates. The wall structure provides mechanical strength to the device and resistance to flow of liquid crystal material which can cause deterioration in the device performance. The walls may extend in two mutually different directions (FIG. 8, 40) to provide mechanical strength and resistance to flow in two directions while the device can still be readily filled. The device is particularly applicable to a ferroelectric liquid crystal device.