Liquid-crystalline halogen compounds, process for their preparation, dielectrics containing these, and electro-optical display element

US4490305A · kind A · utility

Assignee

• Merck Patent GmbH · DE

Inventors

• Rudolf Eidenschink · Mainz, DE
• Michael C. Romer · Rodgau, DE
• Georg Weber · Langen (Hessen), DE

Key dates

• Filing date: Sep 15, 1982
• Grant date: Dec 25, 1984
• Expiry date: Sep 15, 2002

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09K19/12
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Liquid-crystalline halogen compounds of the formula ##STR1## wherein the ring A is 1,4-phenylene or trans-1,4-cyclohexylene; R.sub.1 is alkyl or alkoxy each of 1 to 12 carbon atoms or, when A is 1,4-phenylene, is also cyano; R.sub.2 is alkyl or alkoxy each of 1 to 12 carbon atoms or, when A is 1,4-cyclohexylene, is also chlorine or bromine; and X is fluorine, chlorine or hydrogen; with the proviso that at least one of the substituents R.sub.2 and X is a halogen atom are valuable components in liquid-crystalline dielectrics.