Question

The control and reduction of short fiber content have a direct impact on \(\underline{\hspace{2cm}}\) in a yarn.

• A. Thin places
• B. Thick places
• C. Long thin places
• D. Neps

Hint:

Think of it this way: - Long fibers = easy to comb and align. - Short fibers = difficult to control, they fly around and get tangled. These tangles are called neps. Therefore, Short Fibers \(\rightarrow\) Neps.

Answer 1

The Correct Option is D

Step 1: Define Short Fiber Content (SFC) and Neps. 
- Short Fiber Content: The percentage of fibers in a sample that are shorter than a certain length (e.g., 12.5 mm). High SFC is generally undesirable. 

- Neps: Small, tangled knots of fibers. They appear as defects in the yarn and fabric. Neps are often formed from short fibers or immature fibers that entangle during processing (especially carding). 
 

Step 2: Analyze the relationship. Short fibers lack the length to be controlled properly by the drafting systems in spinning machinery. They are more likely to become disorganized, fly around, and get tangled up with other fibers, directly leading to the formation of neps. Therefore, a high short fiber content is a primary cause of a high nep count in yarn.

Step 3: Evaluate the other options. While high SFC can contribute to overall yarn unevenness (which includes thin and thick places), its most direct and significant impact is on the formation of neps. Controlling and reducing SFC is a key strategy for reducing neps.