When ‘colour’ is applied to a fabric it is termed as dyeing. Dyeing and printing of fabrics is usually done after routine or basic finishes but prior to the application of other finishes. It is mainly done to give colour to the fabric and thus improve the appearance of the fabric.
Dyes and Sources of Dyes
The dyes which are used for colouring fabrics can be classified according to their sources.
These dyes are based on raw materials available in nature (plants, insects and minerals) and are non–polluting.
These dyes are not received from natural sources. They are synthetically made by using various chemicals. Chemical dyes are cheap and easy to apply, with overall good colour fastness but cause environmental pollution.
Stages of dye application
When we go to the market we find it is not only fabrics which are dyed but sewing threads and knitting yarns are also available as dyed materials.
Dyeing may be done during
Both natural and manmade fibers can be dyed at this stage. It gives very uniform dyeing and fast colours. But there is a lot of wastage during further processing of fibres.
Sometimes yarns are also dyed, especially when they have to be sold as such. Hence in embroidery thread, sewing threads and knitting yarn, dyeing is done at the yarn stage.
This is the most popular stage of dyeing. Most of the fabrics which are dyed in a single solid colour are dyed at this stage. This method is a fast method and it is easy to match colours. Blended fabrics can also be dyed.
Sometimes, after stiching the garment, there is a need to dye it, for example, dupattas for suits are dyed after making.