Question

To produce non-woven fabric, web bonding is carried out to convert web of fibres into fabric. The following are types of mechanical bonding:
A. Needle punching
B. Thermal bonding
C. Hydroentanglement
D. Stitch bonding
E. Spray bonding
Choose the correct answer from the options given below :

• A. \( \text{A, D and E Only} \)
• B. \( \text{B and C Only} \)
• C. \( \text{A, B, C, D and E} \)
• D. \( \text{A, C and D Only} \)

Hint:

Needle punching is the standard method for making industrial felts, while hydroentanglement is frequently used to make soft, absorbent wet wipes and medical textiles.

Answer 1

The Correct Option is D

Concept: Non-woven fabrics are made by forming a "web" of loose fibers and then "bonding" them together. Bonding methods are categorized as Mechanical (using physical force), Chemical (using adhesives), or Thermal (using heat).

Step 1: Identify the mechanical bonding processes.
Mechanical bonding involves the physical entanglement of fibers without the use of heat or chemicals:
• Needle punching (A): Hundreds of barbed needles move up and down through the web, physically interlocking the fibers.
• Hydroentanglement (C): Also known as spunlacing, high-pressure water jets are used to tangle the fibers together.
• Stitch bonding (D): A process where the fiber web is secured by stitching it together with yarns, similar to knitting.

Step 2: Identify the non-mechanical processes.

• Thermal bonding (B): Uses heat to melt fibers together (Thermal).
• Spray bonding (E): Uses a liquid adhesive spray to glue fibers (Chemical).

Step 3: Conclusion.
The correct mechanical bonding methods are A, C, and D.