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:
Jun. 18, 1996
Filed:
Mar. 19, 1993
Essilor International, , FR;
Abstract
The invention relates to photochromic compounds of general formula: ##STR1## in which R.sup.a, R.sup.b and R.sup.c denote hydrogen; alkyl; aryl; OR, SR, COR or COOR, in which R denotes hydrogen, alkyl or aryl, amino of formula NR.sub.1 R.sub.2 in which R.sub.1 and R.sub.2 denote hydrogen, alkyl, cycloalkyl, aryl, R.sub.1 and R.sub.2 being capable of forming with the nitrogen atom, a heterocycle containing 4 to 7 members and capable of containing, in addition, one or more heteroatoms chosen from nitrogen, oxygen, sulfur, a halogen atom; a mono- or polyhaloalkyl group; an NO.sub.2, CN or SCN group; n and m denote integers from 1 to 5 depending on the number of substitutions on the nucleus and p may be equal to 1 or 2 depending on the number of substitutions on the nucleus; H is an aromatic heterocycle having 4 to 7 members containing one or more heteroatoms chosen from nitrogen, oxygen, sulfur, these heterocyclic nuclei being capable of being substituted by one or more alkyl, alkoxy, amino, aryl or aralkyl groups or condensed with an aromatic nucleus, and to their use in ophthalmic optics.