An insoluble dye is reduced to a soluble colourless leuco form by an alkaline reducing agent. The fibre is soaked in the dye solution and then exposed to air to develop the colour. The dye is

Question

An insoluble dye is reduced to a soluble colourless leuco form by an alkaline reducing agent. The fibre is soaked in the dye solution and then exposed to air to develop the colour. The dye is (A) mordant dye (B) vat dye (C) azo dye (D) direct dye

Tardigrade Admin · Accepted Answer

Vat dyes are insoluble in water and cannot directly applied. It is reduced to soluble colourless leuco form by an alkaline reducing agent, e.g.,

Q. An insoluble dye is reduced to a soluble colourless leuco form by an alkaline reducing agent. The fibre is soaked in the dye solution and then exposed to air to develop the colour. The dye is

mordant dye

vat dye

azo dye

direct dye

disperse dye

Vat dyes are insoluble in water and cannot directly applied. It is reduced to soluble colourless leuco form by an alkaline reducing agent, e.g.,