Vat dyes are a special class of dyes that work with a special chemistry. Vat dyes are ancient class of dyes based on original natural dyes. Indigo which is now produced synthetically, cotton and wool as well as other fiber can be dyed with vat dyes.
Vat dyes are originally insoluble in water and has no affinity for for cotton , but in reduced form these are converted into leuco form , which is soluble in water and have an affinity for cellulosics.After application the dyes are oxidised back to thier original insoluble form. These dyes have very superior all round color fastness properties.
All the vat dyes are fast, especially to washing. The artificial vat dyes have in many instances taken the places of the older mordant dyes, and their future seems promising, for they are cheaper and easier to apply than the mordants, although not so cheap and convenient as the direct dyes.
Both cotton and wool, as well as other fibers, can be dyed with vat dyes. "Vat dyeing" means dyeing in a bucket or vat. It can be done whenever a solid even shade, the same color over the entire garment, is wanted, using almost any dye, including fiber reactive dye, direct dye, acid dye, etc. The opposite of vat dyeing is direct dye application, such as, for example, tie dyeing. "Vat dyes" are a special class of dyes that work with a special chemistry.
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Vat Class of Colors
Dyeing Vats:- Pad and Jigger Develop
Continuous Dyeing of Vats
Video showing Indigo Vat Dyeing
Important Considerations in Dyeing with Vat Dyes
Print chemistry of vat dyes
Controlling continuous Dyeing by Vat Dyes
Vat Dyes manufacturing
Chenistry and Manufacturing of Vat Dyes
Indigo from Seed to Dye