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. 24, 1984
Filed:
Apr. 28, 1982
Jost von der Crone, Riehen, CH;
Werner Sieber, Basel, CH;
Ciba-Geigy Corporation, Ardsley, NY (US);
Abstract
A photoelectrophoretic imaging process, wherein a suspension of photosensitive pigment particles between two electrodes, at least one of which is transparent, is subjected to the influence of an electric field and exposed to an image, which process comprises using, as photosensitive pigment, an isoindoline of the formula ##STR1## wherein R.sub.1 and R.sub.3 are cyano, --COOR or --CONHR', in which R is alkyl, cycloalkyl, aryl or a heterocyclic aromatic radical, and R' is hydrogen, alkyl, cycloalkyl, aryl or a heterocyclic aromatic radical, R.sub.2 and R.sub.4 are cyano, or wherein R.sub.3 and R.sub.4, together with the carbon atom linking them, form a heterocyclic 6-membered ring. The pigments used in this invention are distinguished by particularly good photoelectrophoretic sensitivity and low fog density.