Industrial Dyes

The sulphur dyes are dissolved in sodium sulphide solution prior to dyeing applications. Generally the best method for dissolving of the dyestuffs is to paste with required amount of turkey red oil and add requisite amount of sodium sulphide and hot water. A 10-12 minutes Boiling ensures complete dissolution of the dyestuffs. After the Filteration of the dissolved colour solution, it can be used to dye fabricas.

Direct Dyes are suitable for dyeing cotton and viscose in the form of fabric, yarn as well as loose cotton. They are also used for dyeing of wool, nylon and pure silk in certain cases.

Reactive Dyes are used for all cellulosic Fibres, Silk & Viscose Rayon. These colours react with cellulose in presence of alkali and also form chemical linkage resulting excellent fastness.

Disperse Dyestuffs are characterised with high degree of dispersion and are specially suitable for dyeing in various forms either alone or as a mixture with other fibres.

Method - The powder, cone, highly cone, and ultra cone brands are kneaded into a paste with water containing a wetting agent. Microfine and ultra dispersed brands are sprinkled in warm water under stirring. Add hot water and bring to the recommended vatting temperature. Add required quantity of caustic soda (previously dissolved in water) under stirring. Sprinkle required quantity of sodium hydrosulphite under stirring. Powder brands are reduced in 15 minutes while microfine and ultra dispersed brands are reduced in 10 minutes. Add the reduced dyestuff solution through filter cloth to the dyebath containing the requisite amount of caustic soda and sodium hydrosulphite at the recommended dyeing temperature.