Options to overcome the environmental

Traditionally, cotton is dyed using water-soluble dyes, but these compounds don t naturally adhere well to cotton, so large amounts of salt must also be added to the mix to make the dye less soluble and better at adhering. The amount of salt needed sometimes approaches ratios of 1-to-l by weight of the fabric. Large amounts of water are also needed it takes eight gallons of water to dye one pound of fabric. 

In cationic fiber modification, a chemical called N-(3-chloro-2-hydroxypropyl) trimethylammonium chloride is applied to the cotton before it is dyed. The chemical gives the cotton fiber a permanent positive electrical charge, which strongly attracts the negatively charged dyes. All cotton dyes have negative electrical charges. 

As a result of the electrical attraction, less dye is needed. The colors in the fabric appear to be more vivid. There is no noticeable change in the texture of the cotton fiber. 

Another benefit of the new process is that it can be done using standard dyeing and finishing machines, so manufacturers don t have to retool then-operations. 

Textile scientists are now focusing their research on how to streamline the new process even further. Currently, they say, one drawback is that the 

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