Patent GB-396050-A (GB)
Title: Protecting agents for acid and alkaline treatment of animal fibres
IPC: D06P1/50
Filed: 1931-10-19
Abstract: Wool, silk, fur, and other animal fibres are protected against the detrimental action of alkaline and acid liquors by adding to the said liquors a preparation consisting of a salt, oxide or hydroxide of magnesium, zinc or cadmium and a natural or waste organic substance of high molecular weight, viz. sugars, soluble starch and other carbohydrates, albuminous compounds and the degradation products thereof, waste liquors from sulphite cellulose and molasses, wherein the metal compound is present in the preparation in amounts up to about 5 per cent (calculated as metal oxide), such that no metallic ions are detectable in said preparation or in aqueous solutions thereof.  The presence of the substances of high molecular weight in these preparations prevent the separation of the metallic oxides when employing alkaline treating liquors.  If desired aminoacetic acid may be added to the preparation in order to facilitate the dispersion of the metallic compound in the organic compound.  In the treatment bath itself conditions must be such that the ratio of the specific metal compound originally present in the preparation to the specific organic compound does not exceed the stated limit of 5 per cent; the baths may contain a compound of one of the other metals specified but not present in the added preparation.  In examples (1) a preparation of a magnesium salt with a sulphite cellulose lye and (2) of molasses, magnesium sulphate and aminoacetic acid, is described.  In further examples, (3) half-wool is dyed in a bath containing sulphur black, sodium sulphide, sodium sulphate and the preparation of (1), and the wool is subsequently dyed with acid dyes: (4) coloured rags are stripped in a bath containing Decraline (zinc-formaldehyde-sulphoxylate) and formic acid together with the preparation of (2).  Reference is made to the use of the preparations in wool-scouring, dyeing wool or silk with vat or sulphur or acid colours, degumming silk, killing and dyeing furs, mordanting wool with chromium or copper mordants, carbonizing wool.  Specification 211,912, [Class 15 (ii), Dyeing, Processes &c. for], is referred to.ALSO:Preparations for protecting wool, silk, fur, and other animal fibres against the detrimental action of alkaline or acid liquors consist of a salt, oxide, or hydroxide of magnesium, zinc or cadmium in combination with one or more of the following organic products:--sugars, soluble starch, and other carbohydrates, albuminous compounds and their degradation products, waste liquors from sulphite cellulose and molasses, and wherein the metal compound is present in amounts up to about 5 per cent (calculated as metal oxide), such that no metallic ions are detectable in said preparation or in aqueous solutions thereof. The organic compound forms with the metallic compound soluble or colloidally dispersed complex compounds or act as protective colloids, and prevent the separation of the metallic oxides in alkaline treatment baths.  Aminoacetic acid may be added to facilitate the dispersion of the metallic compound.  In examples the following preparations are described:--(1) sulphate cellulose waste lye and a magnesium salt; (2) molasses, magnesium sulphate and aminoacetic acid.  Specification 211,912, [Class 15 (ii), Dyeing, Processes &c. for], is referred to.