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. 20, 1976
Filed:
Nov. 21, 1973
Henry Bader, Newton Center, MA (US);
Michael H Feingold, Woburn, MA (US);
Polaroid Corporation, Cambridge, MA (US);
Abstract
An improved method for preparing a compound of the formula: ##SPC1## Where each R can be hydrogen, an alkyl substituent, preferably having from 1-6 carbon atoms or an alkoxy substituent preferably having from 1-6 carbon atoms and each R.sup.1 is hydrogen or an alkyl or an alkanol group. R.sup.2 is an alkylene radical having from 1-6 carbon atoms and X represents the atoms to complete a cyclopentyl or cyclohexyl ring. Metal complexed dyes of the above formula are especially useful in the preparation of photographic image patterns. The improved feature of the method presented involves the preparation of compounds of formula 1 in the presence of weakly basic anion exchange resins to obtain high yields of especially high purity products.