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. 20, 1995
Filed:
Feb. 28, 1994
Joseph Berger, Basel, CH;
Wolfgang Wernet, Kobe, JP;
Ciba-Geigy Corporation, Ardsley, NY (US);
Abstract
Mixtures of salts of organic carboxylic acids and organic compounds of non-salt character, dissolved in a C.sub.1 -C.sub.4 alkanol, can be concentrated or separated with a semipermeable membrane made from a copolyamide or copolyimide-amide which contains (a) a first aromatic diamine radical and (b) a second aromatic diamine radical which carries --SO.sub.3 M groups, where M is H.sup..sym., a monovalent to polyvalent metal cation or an ammonium cation. Provided the first diamine radical contains C.sub.1 -C.sub.4 alkyl groups in the o-positions to the amino groups, the copolymers are radiation-sensitive and can be used for producing protective layers or relief images, development being carded out in an aqueous alkaline medium.