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:
Nov. 16, 1976
Filed:
Jul. 23, 1975
Josef Studinka, Zurich, CH;
Rudolf Gabler, Zurich, CH;
Inventa AG fur Forschung und Patentverwertung, Zurich, CH;
Abstract
Fibers and yarn and a process for preparing them comprising dissolving in concentrated sulfuric acid a polymer containing at least 75 mol percent of an aromatic poly-(1,3,4-oxadiazole) having the repeating structural formul a ##SPC1## In which Ar is ##SPC2## the benzene rings in A or B being substituted or unsubstituted; the linking bonds in A being situated m- or p- with respect to each other, and in B situated m- or p- with respect to X; X being --SO.sub.2 -- or --CO--; and n being 1 or 2. The solution is then spun through a spinneret into a substantially water-free precipitating medium of at least one liquid having the formula (II) ##EQU1## IN WHICH R.sub.1, R.sub.2 and R.sub.3 may be the same or different and are alkyl groups having 1 to 4 carbon atoms, and R.sub.3 may also be H, and in which R.sub.1 and R.sub.2 or R.sub.1 and R.sub.3 may together comprise a divalent alkylene radical, the total number of carbon atoms in R.sub.1, R.sub.2 and R.sub.3 being not more than 8, and in which Z is ##EQU2## a being equal to 1 or 2, b being equal to the valence of Z.