Raw Materials For Webbing

Polyester (PET):
1. High strength and abrasion resistance.
2. Low water absorption; official moisture regain is 0.4% (at 20°C and 65% relative humidity, 100g of polyester absorbs 0.4g of water).
3. Prone to static electricity, pilling, and fuzzing.
4. Resistant to acids but not alkalis. Note: Alkalis at specific concentrations and temperatures can degrade the polyester surface, resulting in a softer fabric hand-feel.
5. Good corrosion resistance and lightfastness.
6. Fabrics made from polyester fibers are wrinkle-resistant, dimensionally stable, easy to wash, and quick-drying.

Polyester Spinning:
1. FDY (Fully Drawn Yarn): Individual filaments are parallel, smooth, and uniform; available in bright, semi-dull, and full-dull (matte) varieties, with luster decreasing in that order.
2. DTY (Drawn Textured Yarn): Individual filaments are crimped; characterized by low elasticity and a bulky texture.
3. DTY Intermingled Yarn (Low-stretch intermingled yarn): Features intermittent intermingling points that enhance filament cohesion (categories include non-intermingled, light, medium, and heavy intermingling; heavy intermingling allows for sizing-free weaving).
Generally, FDY and DTY must undergo sizing or twisting before they can be used as warp yarns.
Sizing: Increases yarn strength and inter-filament cohesion; smooths the fiber surface to facilitate weaving.
Twisting: Increases strength and inter-filament cohesion; imparts a crepe effect to the fabric.

Polyamide (PA) or Nylon (N):
1. Excellent tensile strength; it even surpasses steel wire of the same fineness.
2. Superior abrasion resistance-outperforming other textile fibers-making it suitable for sportswear, socks, parachutes, and cables.
3. Poor moisture absorption (official moisture regain of 4%); prone to static electricity, fuzzing, and pilling.
4. Resistant to alkalis but not acids; soluble in 37.5% hydrochloric acid.
5. Good corrosion resistance but poor water, light, and heat resistance; prolonged exposure to sunlight causes strength loss and yellowing.
6. Garments made from nylon are prone to deformation and wrinkling.
Spinning forms: Primarily FDY and ATY.

Spandex (PU):
Properties: Capable of 500–800% elongation; relatively low strength; good resistance to sweat, seawater, acids, and alkalis; cannot be used alone as warp or weft yarn and must be covered with other yarns.
Main types of spandex covering: Air-covered (spandex is clearly visible) and mechanically covered (spandex is encased within).
Sea-island composite yarn: A composite yarn formed by intermingling and interlacing sea-island filaments with high-shrinkage filaments.
High-shrinkage filament: Features a boiling-water shrinkage rate of 35% (resulting in significant shrinkage in the finished suede fabric).
Sea-island filament: An ultrafine fiber with a single-filament fineness as low as 0.138 denier (creating the characteristic nap/suede feel).

Viscose fiber (R):
1. Chemical composition is identical to cotton, and its properties are similar to those of cotton;
2. Exhibits better moisture absorption than cotton; easy to dye, yielding vibrant colors with good color fastness;
3. Low wet strength (40–60% of dry strength); poor elasticity and abrasion resistance when wet; fabrics made from viscose have poor washability and dimensional stability.
Spinning forms: Viscose filament (rayon); Viscose staple fiber (artificial cotton).

Acetate fiber
1. Official moisture regain of 6%; a semi-hydrophobic fiber;
2. Insufficient strength; possesses a silk-like luster and a smooth, sleek hand-feel;
3. Soft but prone to deformation; poor abrasion resistance;
4. Compared to viscose, acetate fiber has lower strength, poorer moisture absorption, and inferior dyeability, but it surpasses viscose in hand-feel, elasticity, luster, and thermal retention.