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. 25, 1995
Filed:
Sep. 12, 1994
Ivan Orban, Basel, CH;
Martin Holer, Magden, CH;
Ciba-Geigy Corporation, Ardsley, NY (US);
Abstract
A process for the preparation of compounds of the formula I is described ##STR1## in which R.sup.1 and R.sup.2 independently of one another are C.sub.1 -C.sub.7 alkyl; and R.sup.3 is hydrogen or halogen, by reaction of a diazonium salt of a 2-nitroaniline in acid aqueous solution with a phenol dispersed in water. The process comprises employing as the dispersant a C.sub.8 -C.sub.20 alkanesulfonic acid or a corresponding alkanesulfonate or a mixture of sulfonic acid and sulfonate together with a polyvinyl alcohol. The resulting compounds of the formula I can advantageously be reacted further to give benzotriazoles of the formula V ##STR2## which are used as light stabilizers.