摘要:
This invention relates to crosslinked organopolysiloxanes having liquid-crystalline properties in which mesogenic molecules are chemically bonded to the organopolysiloxane lattices. These crosslinked organopolysiloxanes are prepared from silanes or siloxanes containing mesogenic molecules which are capable of being crosslinked by addition or condensation reactions.
摘要:
A composition containing diorganopolysiloxanes and copolymers prepared in the presence of these diorganopolysiloxanes in which the copolymers are derived from monomers consisting of at least ethylene and vinyl acetate. The resulting composition exhibits non-slump properties and does not migrate on vertical surfaces even in the absence of fillers.
摘要:
The invention relates to a method of producing platelets, wherein a material to be processed into platelets is applied in a flowable or gaseous state to a substrate, consolidated, removed from the substrate, and subjected to a crushing or grinding process, wherein the material is applied to the substrate in succeeding layers such that after application, a lamina pack is present which, in cross section perpendicular to its surface, has individual laminae of a thickness of between 0.2-1000 &mgr;m, and said lamina pack, having been stripped from the substrate, is treated in such a way that the material disintegrates into individual laminae and the individual laminae are reduced in size to a particle size of 0.5-10000 &mgr;m.
摘要:
A mixture of crosslinkable liquid-crystalline substances having a chiral phase (LC mixture), containing polymerizable groups, where at least 90% of the polymerizable groups are part of molecules containing at least two polymerizable groups (crosslinker molecules), wherein from 3.2 to 15 mmol of polymerizable groups are present per g of LC mixture. The crosslinked pigments show little color shift in the presence of solvents or upon application to substrate different temperatures.
摘要:
Liquid-crystalline materials having a cholesteric phase with a pitch of less than 400 nm, comprising a) liquid-crystalline organosiloxanes containing dianhydrohexitol derivatives as chiral groups, and b) chiral monomeric additives which induce the same helicality as the respective liquid-crystalline organo-siloxanes.
摘要:
The invention relates to optical elements having image-forming, color- and polarization-selective reflection and containing cholesteric liquid crystals, and to the preparation and use of these elements. In the wavelength- and polarization-selective elements which form an optical image, at least one cholesteric liquid crystal is enclosed in the cavity of constant thickness between two light-transmitting substrates having curved surfaces in such a way that the helix axis of the liquid crystal is aligned perpendicular to the curved surface of the light-transmitting substrates. The elements are suitable for use as beam splitters or recombiners in projection displays.
摘要:
A compound of the general formulaM--(CH.sub.2).sub.n --(O).sub.m --[--D--B--].sub.q --Y, (I)in which M represents a silicon radical having 2 to 5 silicon atoms which are linked together by bridging elements A, and the remaining valencies of the silicon atoms are saturated with radicals R; A is a bridging element selected from the group consisting of C.sub.1 - to C.sub.8 -alkylene radicals and oxygen with the proviso that at least one radical A per M radical is a C.sub.1 - to C.sub.8 -alkylene radical; R represents optionally fluorine or chlorine atom- or cyano group-substituted straight-chain C.sub.1 - to C.sub.10 -alkyl or C.sub.2 - to C.sub.10 -alkenyl radicals, branched chain C.sub.3 - to C.sub.10 -alkyl or C.sub.3 - to C.sub.10 -alkenyl radicals, optionally C.sub.1 - to C.sub.4 -alkyl- , C.sub.1 - to C.sub.4 -alkoxy radicals, fluorine, chlorine, bromine atom, cyano, trifluoromethyl or nitro radical substituted C.sub.6 - to C.sub.12 -cycloalkyl, C.sub.6 - to C.sub.12 -cycloalkenyl, C.sub.6 - to C.sub.12 -alkylcycloalkyl, C.sub.6 - to C.sub.12 -alkylcycloalkenyl, C.sub.6 - to C.sub.12 -aryl or C.sub.6 - to C.sub.12 -aralkyl radicals; n is an integer of from 3 to 12; m is 0 or 1; D represents isocyclic or heterocyclic saturated or unsaturated 5- or 6-membered rings; B represents a linking group selected from the group consisting of a chemical bond, a --COO--, --OOC--, --CH.sub.2 --CH.sub.2 --, --CH.dbd.CH--, --C.tbd.C--, --CH.dbd.N--, --N.dbd.CH--, --CH.sub.2 --O--, --O--CH.sub.2 -- and --N.dbd.N-- group; q is an integer of from 1 to 3; Y is a hydrogen atom or a straight-chain or branched chain C.sub.1 - to C.sub.10 -alkyl or C.sub.1 - to C.sub.10 -alkoxy group or a radical D which is provided with a hydrogen atom or substituted, in which 1 or 2 ring substituents may be C.sub.1 - to C.sub.4 -alkyl, C.sub.1 - to C.sub.4 -alkoxy radicals, fluorine, chlorine or bromine atoms, cyano, trifluoromethyl or nitro radicals, or a cholesteryl radical.These compounds are liquid crystals and can be employed alone or in admixture with other liquid crystals.
摘要:
The invention relates to optical elements based on helical liquid-crystalline substances, having reflection bands of linear-polarized light, and to a process for preparing the same. The optical elements of this invention contain only one optically effective component based on helical liquid-crystalline substances. They reflect light incident perpendicular to the surface in a linear-polarized manner parallel to the direction of incidence of the incident light. The process for preparing the optical elements comprises illuminating a helical liquid-crystalline substance which contains at least one photoisomerizable substance with linear-polarized light in such a manner that this substance is subsequently aligned so that it exhibits at least one reflection band of linear-polarized light on illumination. Suitable helical liquid-crystalline substances are in particular organopolysiloxanes. The optical elements are suitable, for example, for data storage.
摘要:
The present invention relates to cyclic siloxanes which have at least one group of formula (1) bonded to a silicon atom--(CH.sub.2).sub.x --R"--[--L--A--].sub.y --(L).sub.z --T (1),in which x is an integer having a value of at least 2, preferably having a value of from 2 to 10, R" is a chemical bond or a divalent radical of the formula --COO--, --OOC--, --CH.sub.2 --CH.sub.2 --, --CH.dbd.CH--, --C.tbd.C--, --N.dbd.N--, --N.dbd.N(O)--, --CH.dbd.N--, --N.dbd.CH--, --N.dbd.N--, --N.dbd.N(O)--, --N.dbd.CH--, --CH.dbd.N--, or --Si(R).sub.2 --, where the radical R is identical or different and is an optionally substituted hydrocarbon radical having from 1 to 18 carbon atoms, L which is the same or different represents the 1,4-phenylene or 1,4-cyclohexylene radicals which are optionally 2-, 3-, 5- and/or 6-substituted by at least one radical Q, Q is the same or different radical selected from hydrogen, fluorine or chlorine atoms or cyano, methyl or trifluoromethyl groups, A is the same or different and represents divalent radicals R" is a chemical bond or a divalent radical of the formula --CH.sub.2 --O--, or --O--CH.sub.2 --, y is an integer having a value of from 0 to 10, preferably from 0 to 2, z is an integer having a value of from 0 to 10, preferably from 0 to 2, with the proviso that the sum y+z is at least 1, and T is a cholesteryl radical or a substituted or unsubstituted hydrocarbon radical having from 1 to 18 carbon atoms, in which the substituents are preferably selected from the group consisting of halogen atoms, cyano groups, nitro groups, hydrocarbonoxy groups having from 1 to 10 carbon atoms and mixtures thereof.
摘要:
The present invention relates to compounds of the formula ##STR1## in which Y represents an organosilicon radical;R" represents a divalent radical which connects the radical Y to the benzene ring via a chain of at least three atoms;X represents a radical of the formula --COOH, --CN, --CHO, --NH.sub.2 or --OH, in which it is possible to block the hydroxyl group with a protecting group;Z represents the same or different substituents in the 2-, 3-, 5- or 6-position to the radical X, preferably hydrogen or halogen atoms; andp represents a value of 0 to 4;and the use of these and related compounds in the preparation of compounds having liquid-crystalline properties.