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:
Feb. 24, 1981
Filed:
Feb. 28, 1979
Norbert Kollodzeiski, Eppstein, DE;
Rudolf Lowenfeld, Dreieich, DE;
Eberhard Mundlos, Heusenstamm, DE;
Reinhard Mohr, Offenbach am Main, DE;
Kurt Hohmann, Neu-Isenburg, DE;
Hoechst Aktiengesellschaft, , DE;
Abstract
A dyeing process has been found which enables to dye uniformly polyacrylonitrile fiber materials, by using as dyestuffs basic azo dyestuffs being non-quarternized and containing neither cationic quaternary ammonium groups nor cationic N-substituted or N-unsubstituted iminium groups, said azo dyestuffs containing on the other hand at least one unsubstituted or substituted amino group, hydrazino group, amidino group or guanidino group capable of forming salts. The very dyeing process as such is carried out according to usual processing data for dyeing polyacrylonitriles in a slightly acid medium. Especially with the use of several of these dyestuffs for polychromic dyeing, such as trichromic dyeing, special advantages are obtained, insofar that even at cut-rate dyeing periods and for preparing light color shades, there are obtained even dyes with constant color shades, when using these dyestuffs having good migrating properties.