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:
Jan. 12, 1982
Filed:
Sep. 26, 1980
Rudiger Erckel, Eppstein, DE;
Gunter Rosch, Bad Soden am Taunus, DE;
Hoechst Aktiengesellschaft, , DE;
Abstract
Compounds of the formula ##STR1## wherein X is O or S, R.sub.1 and R.sub.2 each are hydrogen, fluorine, chlorine, phenyl, alkyl, alkoxy, dialkylamino, trialkylammonium, acylamino or optionally functionally modified carboxy or sulfo groups, two adjacent radicals R.sub.1 and R.sub.2 optionally forming together a phenylene, a lower alkylene or a 1,3-dioxapropylene group; and A is a group of the formulae ##STR2## in which R.sub.3 is an alpha-, beta- or gamma-pyridyl, pyridyl-methylene, thiophenyl, furanyl, benzofuranyl, pyrazinyl, pyrimidinyl or pyridazinyl group. These compounds, which are suitable as optical brighteners, are prepared by reaction of a compound of the formula ##STR3## with a compound of the formula