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:
Sep. 29, 1981
Filed:
Sep. 17, 1979
Peter Burri, Reinach, CH;
Ciba-Geigy Corporation, Ardsley, NY (US);
Abstract
Substituted 3,6-diaminophthalides of the formula ##STR1## wherein each of R.sub.1, R.sub.2 and R.sub.3 independently represents alkyl of not more than 12 carbon atoms which is unsubstituted or substituted by halogen, hydroxyl, cyano or lower alkoxy, or represents cycloalkyl, benzyl, or benzyl which is substituted by halogen, lower alkyl or lower alkoxy, and R.sub.1 can also be hydrogen and R.sub.3 can also be phenyl, or R.sub.1 and R.sub.2, together with the nitrogen atom to which they are attached, represent a 5- or 6-membered heterocyclic radical and the ring A is unsubstituted or substituted or contains a fused, unsubstituted or substituted benzene or heterocyclic ring. These compounds are suitable in particular for use as color formers in pressure-sensitive or heat-sensitive recording materials.