Question

The main purpose of scouring in cotton processing is to remove:

• A. Natural coloring matter
• B. Waxes and impurities
• C. Lignin
• D. Synthetic finishes

Hint:

Scouring increases cotton absorbency, which is essential for effective bleaching, dyeing, and finishing.

Answer 1

The Correct Option is B

Step 1: Understanding scouring.
Scouring is a preparatory chemical process applied to cotton fabrics or yarns before bleaching and dyeing. Its main objective is to clean the cotton material thoroughly.
Step 2: Nature of impurities in cotton.
Raw cotton contains natural impurities such as waxes, oils, pectins, fats, and dirt. These substances make cotton hydrophobic and interfere with dye absorption and finishing processes.
Step 3: Analysis of options.
(A) Natural coloring matter: Removal of natural color is primarily achieved by bleaching, not scouring.
(B) Waxes and impurities: Correct — Scouring removes hydrophobic substances like waxes, oils, and dirt, improving absorbency.
(C) Lignin: Lignin is mainly present in bast fibres, not cotton.
(D) Synthetic finishes: Synthetic finishes are applied later in processing and are not the target of scouring.
Step 4: Conclusion.
The primary purpose of scouring is to eliminate waxes and natural impurities so that cotton becomes absorbent and suitable for further processing.