Question

When compared to $40^s$ cotton shirting, the crease recovery of Polyester shirting from 50 D x 50 D (Tex x Tex) is

• A. Equal
• B. Higher
• C. Lower
• D. Normal

Hint:

• Crease Recovery Ability of a fabric to recover from wrinkling.
• Polyester} fibers are highly resilient and have excellent crease recovery due to their chemical structure and ability to be heat-set.
• Cotton} fibers (natural cellulose) have poor crease recovery, especially when wet, due to the nature of hydrogen bonding in cellulose. Cotton fabrics wrinkle easily unless treated with special finishes.
• Therefore, polyester fabrics generally have much higher crease recovery than untreated cotton fabrics.

Answer 1

The Correct Option is B

Crease recovery (or wrinkle recovery) is the ability of a fabric to return to its original shape after being creased or wrinkled. It is an important property for apparel fabrics, affecting their appearance during wear. Comparing Polyester and Cotton:

• Polyester: Polyester fibers are synthetic, thermoplastic, and have high resilience. They are known for their excellent crease recovery, especially when dry and also reasonably good when wet ("wash and wear" properties). The molecular structure of polyester (long, linear, crystalline polymers with strong intermolecular forces that can be heat-set) contributes to this.
• Cotton: Cotton fibers are natural cellulosic fibers. Cellulose has many hydroxyl groups which can form hydrogen bonds. When cotton is creased, especially in the presence of moisture, these hydrogen bonds can break and reform in new positions, "setting" the crease. Cotton generally has poor crease recovery, particularly when wet, unless it is chemically treated with a wrinkle-resistant finish (e.g., crosslinking resins).

The question compares a polyester shirting fabric with a cotton shirting fabric.

• Polyester shirting (e.g., from 50 Denier yarns) will exhibit the characteristic high crease recovery of polyester.
• $40^s$ cotton shirting ($40^s$ NeC is a common count for shirting) made from untreated cotton will have relatively poor crease recovery.

Therefore, when compared to $40^s$ cotton shirting, the crease recovery of Polyester shirting is significantly Higher. \[ \boxed{\text{Higher}} \]