The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 27, 1982
Filed:
Jul. 18, 1980
Kabushiki Kaisha Suwa Seikosha, Tokyo, JP;
Abstract
Ester compounds suitable for use in liquid crystal compositions are provided. The ester compounds are (2'-chloro-4'-n-alkylphenyl)-3-cyano-4-n-alkoxybenzoates represented by the general formula: ##STR1## wherein R and R' are straight-chain alkyl groups having from one to eight carbon atoms. The ester compounds alone do not exhibit a liquid crystal phase, but have a relatively high value of dielectric anisotropy. Addition of minor amounts of at least one such ester compound to a liquid crystal composition lowers the value of the dielectric anisotropy of the composition in the high frequencies range. Such compositions are particularly well suited for the two-frequency matrix-addressing drive in a display of complex characters or graphic displays by reducing the driving voltage. The ester compounds in accordance with the invention are prepared by condensing a 3-bromo-4-n-alkoxybenzoyl chloride having the general formula: ##STR2## and a 2-chloro-4-n-alkylphenol having the general formula: ##STR3## to prepare a (2'-chloro-4'-n-alkylphenyl)-3-bromo-4-n-alkoxybenzoate having the general formula: ##STR4## wherein R and R' are straight-chain alkyl groups having from one to eight carbon atoms, and reacting the benzoate (IV) with cuprous cyanide to yield the desired ester (I).