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:
Aug. 29, 2006
Filed:
Jul. 10, 2002
Stephen M Kelly, Hull, GB;
Neil L Campbell, Teddington, GB;
Warren L Duffy, Southampton, GB;
QinetiQ Limited, London, GB;
Abstract
The use of a compound of formula (I) wherein Ris an alkyl or alkenyl group, either of which may be optionally interposed with one or more oxygen or sulphur atoms, Ris an alkyl or alkenyl group, Y' and Y″ are independently selected from oxygen or sulphur, n is an integer from 1 to 5, X is a direct bond or a Calkylene or Calkenylene chain, and A is group comprising one or two rings which are independently selected from aryl, heterocylic or cycloalkyl rings, and when there are two rings, they are bonded together directly or by way of a Calkylene or Calkenylene group, for increasing the u.v. stability of a liquid crystal mixture. The compounds of formula (I) are u.v. stable and are useful in liquid crystal devices which are exposed to high levels of u.v. light such as phosphor display cells. Certain compounds are novel and these form a further aspect of the invention.