Textile finishing: during fibre and fabric preparation, “scouring” is a finishing operation primarily intended to accomplish which treatment of the fibres?

Introduction / Context:
Scouring is a standard wet-processing step in textiles that prepares fibres or fabrics for subsequent finishing and dyeing. The operation focuses on removing natural and processing-added impurities so that dye uptake is uniform and final properties are reproducible. Understanding what scouring does helps distinguish it from dyeing, bleaching, and heat-setting steps.

Given Data / Assumptions:

• Scouring is performed before dyeing/printing on many substrates.
• Typical baths contain alkali and surfactants (detergents/wetting agents).
• Target impurities include waxes, oils, sizing agents, and dirt.

Concept / Approach:
In scouring, the fibre or fabric is treated with aqueous solutions—commonly alkaline detergents—under controlled temperature and time to emulsify and saponify fatty substances, remove lubricants, and eliminate processing aids. This increases hydrophilicity, improves wetting, and ensures level dyeing. Scouring is not a mechanical stretching, glycol plasticisation, or the act of dyeing itself; it is a cleaning and preparation operation.

Step-by-Step Solution:

Verification / Alternative check:
Process flow diagrams in textile finishing show scouring preceding bleaching/mercerisation/dyeing, corroborating its role as a cleaning step.

Why Other Options Are Wrong:

• Improving stretchability: relates to fibre type and thermal/mechanical treatments.
• Dyeing/colouring: a separate, later operation.
• Glycol soaking: not a standard scouring practice.
• Heat-setting: a thermal process to stabilise dimensions, not scouring.

Common Pitfalls:
Equating scouring with bleaching; bleaching removes color bodies, scouring removes oils/waxes/sizes.

Final Answer:
Detergent solution washing to remove impurities