Abstract: New photopolymerizable liquid crystalline dioxetane compounds are provided having the general formula I: wherein R1 and R2 are independently selected from straight or branched C1-C4 alkyl and hydrogen; X and X′ are independently selected from oxygen, sulfur, a single covalent bond, —O—CO—, —CO—O—, and —O—CO—O—; Y and Y′ are spacer groups having each independently 1 to 30 carbon atoms (linear or branched), in which the carbon chain may be interrupted by oxygen in the ether function or by sulfur in the thioether function; Z and Z′ are independently selected from oxygen, sulfur, a single covalent bond, —O—CO—, —CO—O—, and —O—CO—O—; and M is any suitable mesogenic group. Also, compositions are provided containing one or more compounds of formula I, as well as methods of preparing said compounds and compositions.

Abstract: The invention relates to a method of manufacturing a patterned layer of a polymer material having a cholesteric order, in which the material is oriented in such a way that the axis of the molecular helix of the cholesterically ordered material extends transversely to the layer, and in which the layer is patterned in that it comprises at least one region in which the pitch of the molecular helix differs from that of another region. This inventive method comprises the following steps: a. providing a layer of a cholesterically ordered material comprising a quantity of a convertible compound which in its non-converted and in its converted state determines the pitch of the cholesterically ordered material to a different extent, in which the conversion of said compound may be induced by radiation, b. irradiating the layer in accordance with a desired pattern so that at least a part of the convertible compound in the irradiated parts of the layer is converted, c.

Abstract: New photopolymerizable liquid crystalline dioxetane compounds are provided.

Abstract: The present invention relates to a cholesteric color filter (CCF) provided with a coating preventing the ingress of oxygen, and a method for making such a cholesteric color filter. It further relates to a device, such as a liquid crystal display (LCD), comprising a substrate provided with such a cholesteric color filter. The topcoat is preferably curable by electromagnetic radiation.

Abstract: The invention relates to a method of manufacturing a patterned layer of a polymer material having a cholesteric order, in which the material is oriented in such a way that the axis of the molecular helix of the cholesterically ordered material extends transversely to the layer, and in which the layer is patterned in that it comprises at least one region in which the pitch of the molecular helix differs from that of another region.

Abstract: The invention relates to a method of manufacturing a patterned layer of a polymer material having a cholesteric order, in which the material is oriented in such a way that the axis of the molecular helix of the cholesterically ordered material extends transversely to the layer, and in which the layer is patterned in that it comprises at least one region in which the pitch of the molecular helix differs from that of another region. This inventive method comprises the following steps: a. providing a layer of a cholesterically ordered material comprising a quantity of a convertible compound which in its non-converted and in its converted state determines the pitch of the cholesterically ordered material to a different extent, in which the conversion of said compound may be induced by radiation, b. irradiating the layer in accordance with a desired pattern so that at least a part of the convertible compound in the irradiated parts of the layer is converted, c.

Abstract: The invention relates to a method of providing a decorative coating or text or the like on articles, like shavers, GSM's, cards, etc. The coating comprises a region-wise optically modified (patterned) cholesteric liquid crystalline layer, which is transferred onto a surface of the article by means of a transfer operation. The so-called in-mold decoration technique has been found to be very advantageous for the transfer of decorative (patterned) cholesteric liquid crystalline layers. In this technique the layer is (releasably) deposited on a plastic carrier foil and provided with a layer of adhesive. The assembly is inserted in an injection mold before the injection molding of polymer material starts. In this way decorative coatings (e.g. multi color images) and texts or the like can be even applied onto, non-even and slightly curved substrates.

Abstract: The invention relates to a method of preparing an oriented cross-linked polymer, which comprises the steps of orienting and polymerizing a liquid-crystal composition. The liquid-crystal composition comprises a monomer which reduces the order during polymerization. This makes it possible to obtain oriented cross-linked polymers having a low degree of optical anisotropy and optical elements having a relatively low degree of scattering.

Abstract: Cholesteric polarizer and the manufacture thereof. A broadband cholesteric polarizer is described, as well as a method of manufacturing such a polarizer. Said polarizer comprises an optically active layer of a polymer material having a cholesteric order, said material being oriented so that the axis of the molecular helix extends transversely to the layer. In accordance with the invention, the polarizer is characterized in that the pitch of the molecular helix in the layer is varied in such a manner that the difference between the maximum pitch and the minimum pitch is at least 100 nm. The optically active layers are preferably provided on substrates which bring about a conversion of circularly polarized light into linearly polarized light. Three different methods of manufacturing such broadband polarizers are described.

Abstract: A description is given of an electroluminescent device (1) having an LED structure, which is composed of an active layer (7) of oriented liquid-crystalline and electroluminescent compounds and a transparent positive electrode layer (5) which is preferably made from an electroconductive polymer. By previously rubbing the electrode layer (5) in one direction with a velvet cloth, an orientation is induced in the molecules in the active layer (7), the orientation being frozen by cooling or polymerization. The electroluminescent device (1) emits polarized light whose direction of polarization is parallel to the direction of rubbing.

Abstract: A broadband cholesteric polarizer is described, as well as a method of manufacturing such a polarizer. Said polarizer comprises an optically active layer of a polymer material having a cholesteric order, said material being oriented so that the axis of the molecular helix extends transversely to the layer. In accordance with the invention, the polarizer is characterized in that the pitch of the molecular helix in the layer is varied in such a manner that the difference between the maximum pitch and the minimum pitch is at least 100 nm. The optically active layers are preferably provided on substrates which bring about a conversion of circularly polarized light into linearly polarized light. Three different methods of manufacturing such broadband polarizers are described.