Name: Claire
Message: I am currently studying textile design at Huddersfield university and am undergoing an assignment for which i need to know what dye class I would use to dye a 50%cotton/50%polyester mix and am having trouble deciding which group of dyes i would use and was woundering if you could point me in the right direcection?
many thanks.

There is no class of dyes which will dye both the cotton and the polyester in a single step. Polyester is dyed with disperse dye, which washes out of cotton. Cotton can be dyed with any of several classes of dye, such as fiber reactive dye or direct dye, but none of these will be permanent on polyester.

For non-industrial dyeing, the best use of 50% polyester/50% cotton is to dye the cotton alone, and accept the fact that leaving the polyester undyed will result in either a pastel or a heathered effect, depending on how the two fibers have been combined.

Note, however, that my information is based only on dyes which are available to individuals who are not in the textile industry; there may be some sort of industrial-use only dye with which I am less familiar.