The ill-effects of man-made or chemical dyes
• Chemical dyes have a mild to noticeable effect on the skin
• Artificial dyes have a tendency of spreading in the next or after a few washes. Fading, dullness or change of colour in a short period after repeated washes, is a foregone conclusion for chemical dyed apparel.
• Chemical dyes harm human life and pollute when used. There is ban on certain class of azo-dyes, in the light of possible hazards to life.
• Land close to a water body which gets polluted by chemical dyes is also affected adversely.
Certain limitations concerning Natural Dyes
Despite the known ill-effects of chemical dyes which are easily available and much cheaper compared to Natural dyes, there are certain limitations to the use of Natural Dyes in a big way.
- The cost is relatively more compared to that of chemical dyes, since extraction from the raw material and its further process is complicated.
- There is limited know how and technical capability regarding the same
- The extraction from the source is so small that the required quantity for the dyeing process in a batch process would entail a huge supply of raw material as compared to the same quantity of chemical dye available for it
- Getting most shades within a colour is not possible or its process is currently not known
- Blending of colours is also a limiting factor. (Very few natural dyes can be blended to achieve the desired colour).
- Many natural dyes require the use of chemicals called mordants to bind the dye to the textile fibres; tannin from oak galls, salt, natural alum, vinegar, and ammonia from stale urine were used by early dyers.
- Easy and cheap methods for the extraction of colour from natural substances are still being explored
- There is a general lack of sufficient concern for the environment.