Question

The mordant is:
A. A dye colour that bites into the fiber
B. A metallic ion that attaches to fiber and causes a colour emission. A chemical that stops the dye process
C. A metallic ion or salt added to the dye bath to make dyes less colorfast forming a bridge between the dye and the fiber
D. None of these.

Answer 1

Hint: A Mordant is an inorganic oxide that is used to set the dyes and is also known as dye fixative. Fabric or yarn is treated with a mordant before dyeing to ensure the color is fixed on then after the process of dyeing.

Complete step by step answer: A mordant is an agent that helps binding the dye to the fiber and it's not a color in itself, so the option A doesn’t hold true for Mordant. It is a mineral salt that is attached to the fiber and prevents color bleeding and it enhances the dye process. Hence, the statement of Option B is also not correct. These are the metallic ions that form coordinate bonds with the dye and improve the color fastness of the dye. Hence, the statement of option C is also not correct.
Hence, none of the statement of the question holds true for Mordant, hence the answer is option D.

Additional Information:
There are three methods that can be used for mounting.
-The material to be dyed is treated with mordant followed by dye.
-The mordant is mixed directly into the dye bath
-The fibre obtained after dyeing is treated with mordant.

Note: Mordants are now normally used in dyes involving small batches and are replaced by dyes that stick to a substance using non-ionic bonds also called as directs in case of large industries. Alum is one of the most commonly used mordants and other mordants being used are: Tannic acid, sodium chloride.