Question

What role do Al3+, Cu 2+, and Fe 2+ play in mordant dyeing?

Answer 1

Ans:- in mordant dyeing metal ion (Al3,Cu2+ and Fe2+) used as mordant which increase affinity for dye and fiber ,it improves affinity of dyes and makes dye-mordent-fiber complex , metal salt are cationic and all acid dyes are anionic and when metal salts add their affinity is increased large. they applies on fiber before applying dye ,it increase dye-metal complex formation to improve fastness .however Al3,Cu2+ and Fe2+ also responsible to produce various sheds of colour when used with natural dyes.