SU98059A1 - Method of dyeing fibrous materials of plant origin with sulfur dyes - Google Patents

Description

When dyeing heavy cotton and linen fabrics with sulphurous dyes in aisle machines, especially if the material is dyed with harsh or poorly prepared material, irokrasus is usually not completely satisfactory.

To eliminate this drawback, various measures are taken, which include: good preparation of the fabric before dyeing (decoction, desizing), repeated pressing during dyeing, introduction of active wetting agent into the red bath, increasing the duration of the dyeing process, raising the temperature of the dyebath, etc. However, these measures complicate the process, increase its cost and are not always effective. At the same time, it is necessary to take into account that poor prokras of the tissue and normal dyeing with sulfur dyes in the idiot apiarats is a natural consequence of the ratios between cellulose and dye-solution with the proper dyeing effect; the last properties of the colloidal system.

For dyeing plant fiber materials and sulfur dyes with lime, the water soluble bisulphite compounds of these dyes are also used in the same sodium sulphate bath, however, the paint over and this method is not entirely satisfactory.

It is concluded that with the above water-soluble bisulfite compounds, good irokras can be achieved, including heavy fabrics, twisted yarn, and the like, stained to a harsh condition, if the kaspel process is divided into two stages. First stud :; impregnating the fibrous material to be dyed; an aqueous solution of a water-soluble bisulphite compound of a sulfur dye, and the second stage in a process impregnated with the above; in C; ioco6y of a volocaustic material with a hot aqueous solution of sodium sulphide,

As a result, the bisulfite compound of the sulfur dye is converted on the fiber to its leuco compound.

Between these two processes, the fibrous material should be dried or only dried. After treatment with a solution of sodium sulfide, the usual oxidation in air and washing are followed.

Example. The first bath is made up according to the following recipe: a water-soluble bisulfonate compound of the blue dye Glavanilproduct 100 g

contact10

water until 1000

The fabric is plus with this solution at 60 °, wrung out, dried to a moisture content of 40-bo / o, treated within a few seconds with a 2-S / Q solution of sodium sulphide at 80-100 °, wrung out, matured (oxidized in air), washed

first with cold and then with hot water, wring out and dry.

Subject invention

The method of dyeing fibrous materials of plant origin with sulfur dyes using water-soluble bisulfite compounds of the latter and sodium sulphide is distinguished by the fact that, in order to improve the coloring of heavy, hard fabrics, twisted yarn and the like, the material being dyed is first soaked with a hot aqueous solution of bisulfite sulfur dye compounds, then dried or only dried and treated with a hot sodium sulphide solution, then oxidized in air and washed manner.