Vat dyes are insoluble in water but can be made soluble through a chemical reduction process, allowing them to affix to textile fibers. Once affixed, the dye is re-oxidized to its insoluble form. Vat dyes are especially fast for cotton, linen, and rayon and are used with mordents to dye other fabrics like wool, nylon, polyesters, acrylics, and mod acrylics.

1. Vat Dyes

2. • Vat Dyes
• Vat dyes are insoluble in water and cannot dye fibers directly.
However, they can be made soluble by a reduction in alkaline solution
which allows them to affix to the textile fibers. Subsequent oxidation
or exposure to air restores the dye to its insoluble form. Indigo is the
original vat dye. These dyes are the fastest dyes for cotton, linen and
rayon. They are used with mordents to dye other fabrics such as wool,
nylon, polyesters, acrylics and mod acrylics.