Liquid crystal display

US5578241A · kind A · utility

Assignee

• Merck Patent GmbH · DE

Inventors

• Herbert Plach · Darmstadt, DE
• Bernhard Rieger · Langenau, DE
• Volker Reiffenrath · Roßdorf, DE
• Eike Poetsch · Mühltal, DE

Key dates

• Filing date: May 18, 1993
• Grant date: Nov 26, 1996
• Expiry date: May 18, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09K2323/0271
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to a liquid crystal display element which contains an electrically switchable, dielectrically positive twisted nematic liquid crystal layer between two substrates which together with a frame form a cell, and two layers with alignment layers thereon applied to the substrates. The liquid crystal mixture is based on SFM compounds. One of the electrodes forming an active matrix of non-linear switching elements is integrated within each picture element while the other electrode is the counter electrode. The alignment layer is an organic polymer layer which may be essential uniformly aligned by rubbing. The alignment layer results in an essential homogenous surface alignment of the liquid crystal layer with a surface tilt angle. The liquid crystal material comprises at least 30 wt. % of one or more compounds according to formula I ##STR1## wherein R, Z.sup.1, Z.sup.2, A.sup.1, A.sup.2, X, Y and n are herein defined, and the alignment layer is based on at least partially fluorinated polyimides.