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Dyeing and printing defects pdf

Cotton being dyed manually in contemporary India. Since the dyeing and printing defects pdf-19th century, however, humans have produced artificial dyes to achieve a broader range of colors and to render the dyes more stable to resist washing and general use. The first known use of the word dye was before the 12th century. The development of new, strongly colored synthetic dyes followed quickly, and by the 1870s commercial dyeing with natural dyestuffs was disappearing.

Dyes are applied to textile goods by dyeing from dye solutions and by printing from dye pastes. Methods include direct application and yarn dyeing. This renders the dye soluble so that it can be absorbed by the fiber since the insoluble dye has very little substantivity to the fiber. Direct dyes, a class of dyes largely for dyeing cotton, are water-soluble and can be applied directly to the fiber from an aqueous solution. Most other classes of synthetic dye, other than vat and surface dyes, are also applied in this way. Environmental concerns have now restricted their use, and they have been replaced with reactive and metal complex dyes that do not require mordant. Common forms are the package form and the hanks form.