Question

The primary functions of Spin finish are \(\underline{\hspace{2cm}}\). 
A. Lubrication of fiber surface 
B. Drawing of filaments 
C. Antistatic action 
D. Cohesion of filaments

• A. A, C and D only
• B. A, B and C only
• C. A, B, C and D
• D. B, C and D only"

Hint:

A spin finish gives a synthetic yarn the properties it needs to be processed. Think of it as a "processing aid" that provides: - Lubrication (to slide easily). - Antistatic (to prevent static buildup). - Cohesion (to hold the bundle together).

Answer 1

The Correct Option is A

Step 1: Define "Spin Finish." Spin finish is a liquid mixture of chemicals (lubricants, antistatic agents, emulsifiers) applied to the surface of synthetic filaments immediately after they are extruded and solidified.

Step 2: Analyze the purpose of applying these chemicals.
- A. Lubrication of fiber surface: This is a critical function. The finish reduces the friction between the fast-moving filaments and machine parts (like guides and rollers), preventing abrasion and filament breakage during subsequent processes like drawing and winding.
- B. Drawing of filaments: Spin finish is applied before drawing to facilitate it, but the finish itself does not cause the drawing (stretching) of filaments. Drawing is a mechanical process.
- C. Antistatic action: Synthetic fibers are electrical insulators and build up static charge easily due to friction. This causes filaments to repel each other and creates processing problems. The spin finish contains antistatic agents that help dissipate this charge.
- D. Cohesion of filaments: The finish makes the individual filaments in a yarn bundle stick together slightly (providing cohesion). This prevents the yarn from becoming too bulky or loopy and ensures it processes as a compact bundle.

Step 3: Identify the primary functions. The primary functions are lubrication (A), providing antistatic properties (C), and providing cohesion to the filament bundle (D). Drawing (B) is a separate mechanical process.