Improvement in the Art of Dyeing Cotton and other Vegetable Fibres with Alizarin-red and other Alizarin-dyes.

摘要

26,414. Koblischke, A. Nov. 29. Dyeing.-Alizarin dye-baths are prepared with pure water, such as water of condensation, rain water, or distilled water, and are used for dyeing cotton and other vegetable fibres in the shape of aggregations of loose fibres, or as cops, star spools, rovings, or slivers. In an example, a bath is formed by adding to 1200 litres of water of condensation, 4 kilograms of 20 per cent alizarin dissolved with 500 grams of calcined soda or other alkali, and 100 litres of clear lime water ; tannin may also be added. After dyeing in the above bath, the goods are treated with a weak acid bath (preferably of an organic acid such as acetic, formic, or lactic acid) to which are added small quantities of tin salt or tin solution, prepared from stannouschloride and nitric acid. Specification No. 15,829, A.D. 1893, is referred to.