Hoechst Aktiengesellschaft

Norbert Rosch

Takamasa Harada

Claus Escher

Rainer Wingen

Gerhard Illian

Peter Wegener

Heinz Rieger

Javier Manero

Dieter Ohlendorf

Gerd Illian

Anke Kaltbeitzel

Hans-Rolf Dubal

Dietmar Jungbauer

Michael Magerstadt

A ferroelectric liquid crystal mixture containing two or more components, at least one of which is a complex ligand for ions, in particular for cations, is particularly suitable for use in ferroelectric liquid crystal displays.

Use of complex ligands for ions in ferroelectric liquid-crystal mixtures

Stabilized complex ligands and their use in liquid crystal displays

A process for producing a liquid-crystal cell by using a ferroelectric liquid crystal (FLC) composition containing at least one oleophilic substance that exhibits liquid crystallinity and at least one additive having lower boiling point than said substance, characterized in that said FLC composition is charged into the cell under high-temperature and high-vacuum conditions, provided that the two conditions will not overlap, or will overlap for a sufficiently short time to effectively prevent the evaporation of said additive.

Process for producing ferroelectric liquid-crystal cells with oleophilic

Alignment layers containing cyclic structural elements

Modified polysugar as an alignment layer for liquid-crystal displays An alignment layer for liquid-crystal displays (LCDs) contains

Modified polysugar as the alignment layer for liquid-crystal displays

Ferroelectric liquid-crystal display of high contrast and brightness. The use of alignment layers containing compounds having an amphiphilicity-providing effect increases the contrast and brightness of the image in FLC displays.

Ferroelectric liquid-crystal display of high contrast and brightness

Ferroelectric liquid crystal display comprising outer substrates, electrodes, polarizer(s), ferroelectric liquid crystalline material and alignment layer(s), in which the ferroelectric liquid crystalline material has a spontaneous polarization of Ps&gt;20 nC.cm.sup.-2 and a natural helical pitch of less than half of the cell thickness, and the alignment layer comprises at least one lipophilizing, lipophilic and/or amphiphilic compound. The liquid crystal display according to the invention exhibits a short switching time and a significantly reduced surface memory effect, and thus achieves an improved display contrast.

Ferroelectric liquid crystal display with liquid crystal mixtures having

Process for producing ferroelectric liquid-crystal cells

Electro-optical display devices having a cell thickness of 1 to 10 .mu.m, and containing ferroelectric liquid crystalline mixture, electrodes, alignment layer(s), in which the ferroelectric liquid crystalline mixture has a spontaneous polarization of Ps&gt;20nC.cm.sup.-2 and a natural helical pitch of less than a half of the cell thickness, and contains lipophilizing, lipophilic or amphiphilic compounds for eliminating ionic impurities, Ferroelectric liquid crystal compositions according to the invention show a significantly reduced surface memory effect and an improved display contrast.

Ferroelectric liquid crystal mixtures containing lipohilizing,

A liquid-crystalline mixture comprising at least two components, the first being an aromatic mercapto compound of the formula (I) ##STR1## R.sup.1, R.sup.2, R.sup.3 and R.sup.4, independently of one another, are hydrogen, alkyl having 1 to 8 carbon atoms or alkoxy having 1 to 8 carbon atoms,

Ferroelectric liquid-crystal mixtures containing mercapto compounds

Addition of coronands and cryptands to FLC-mixtures makes it possible to bring the FLC material into a homogeneous 'bookshelf' or 'quasi-bookshelf' geometry. When such a FLC mixture is used, displays which have been shock-damaged can be regenerated by applying a suitable electric field for a short period of time.

Process for the production of an impact-resistant liquid crystal

A liquid crystal mixture composed of at least two components containing as one component a macrocyclic compound of the general formula (1) ##STR1## in which a, b, c, d, e, f, independently of one another, are an integer from zero to 4, a+b+c+d+e+f being greater than 7, and --A--, --B--, --C--, --D--, --E--, --F--, identical or different, are, for example, --CH.sub.2 --, --CH.dbd.CH--, --CO-- or --COO--, leads in FLC displays to the formation of a uniform alignment and avoids twist states, which is reflected in a significantly improved contrast.

Macrocyclic compounds as component for ferroelectric liquid crystal

The occurrence of twist states in FLC displays can be suppressed by adding ionophores to FLC mixtures. Applicable ionophores are amides of the general formula I ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 e.g. are alkyl, cyclohexyl, phenyl or benzyl and X is alkylene with --CH.sub.2 -groups being replaced by --O--, 1,2-phenylene or 1,2-cyclohexylene.

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Frankfurt am Main, Germany

Norbert Rosch