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. 07, 1982
Filed:
Apr. 01, 1981
Wolfgang Bauer, Maintal, DE;
Heinz Dickmanns, Frankfurt am Main, DE;
Konstantin Morgenroth, Maintal, DE;
Kuno Reh, Frankfurt am Main, DE;
Joachim Ribka, Offenbach-Burgel, DE;
Cassella Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
The aqueous dyestuff formulation of an tetrakisazo direct dyestuff which is stable to alkali and contains at least one aromatic hydroxyl group and/or enol group and at least one group conferring solubility in water, or a mixture of such azo direct dyestuffs, is characterized in that it has a pH value equal to or greater than 12 and is prepared by mixing an azo direct dyestuff which is stable to alkali, water and a tertiary alkali metal phosphate and/or alkali metal metasilicate and/or alkali metal hydroxide, and by choosing the proportions such that the dyestuff formulation contains 5 to 50% by weight of dyestuff and has a pH value equal to or greater than 12. The dyestuff formulation is used, after dilution with water, for dyeing and printing natural or synthetic materials containing hydroxyl groups.