Every fabric you buy comes down to a handful of fibers, and each one behaves differently in wear, washing and printing. The fibers covered here are cotton, wool, silk, linen/hemp, polyester, nylon (polyamide), acrylic, spandex, viscose/rayon, modal and lyocell — with what each is best at, where it fails, and how to care for the finished garment. Use this as a quick reference alongside our fabric library when specifying a new collection.
How Fabrics Are Classified
For sourcing purposes, the practical split is between natural fibers (cotton, wool, silk, linen, hemp) and man-made fibers — either regenerated cellulose (viscose/rayon, modal, lyocell) or synthetic polymers (polyester, nylon/polyamide, acrylic, spandex). Most performance garments blend fibers, usually a base fiber plus a small percentage of spandex for stretch. Blends such as polyester-cotton, nylon-cotton and cotton-poly-nylon combine the strengths of each component.
Fiber Quick Reference
| Fiber | Key Properties | Best For | Care Notes |
|---|---|---|---|
| Cotton | Soft, breathable, moisture-absorbing; comfortable against skin. | Casualwear, tees, hoodies, athleisure. | Wash cool (≤30°C), low-iron; can shrink and wrinkle if not pre-shrunk. |
| Wool | Warm, elastic, excellent drape; holds colour well. | Warm-up layers, knitwear, premium outerwear. | Dry-clean preferred; do not tumble-dry or bleach. |
| Silk | Smooth, lustrous, light, good moisture management. | Premium linings, lifestyle pieces. | Hand-wash cool with neutral detergent; no chlorine bleach; dry in shade. |
| Linen / Hemp / Ramie | Strong, highly breathable, cool to wear, dries fast. | Summer casualwear. | Do not wring hard or scrub; press damp; avoid direct sun. |
| Polyester | Strong, quick-drying, wrinkle- and shape-resistant; best substrate for digital printing. | Performance activewear, prints, value ranges. | Machine-wash cool; low heat; a drier hand feel than nylon. |
| Nylon / Polyamide | Softer and smoother than polyester; excellent abrasion resistance and recovery. | Premium leggings, sports bras, swimwear. | Wash cool; yellows with long sun exposure; damages in chlorine faster than polyester. |
| Acrylic | Wool-like warmth and loft, light, colour-fast, good light resistance. | Fleece-type knits, casual sweaters. | Wash cool; prone to pilling; dry flat. |
| Spandex / Elastane (Lycra) | High elongation (roughly 4.5–8×) with strong recovery; used in small percentages. | Stretch in leggings, swim, tops, bands. | Wash cool; avoid chlorine, heat and prolonged sun to protect stretch. |
| Viscose / Rayon | Very soft, silk-like drape, good moisture absorption, low static. | Casual fashion, linings. | Hand-wash cool and gently; weak when wet; do not wring; keep out of direct sun. |
| Modal / Lyocell (Tencel) | Regenerated cellulose with a soft, smooth hand and good dimensional stability. | Soft casualwear, premium basics. | Machine- or hand-wash cool; no bleach; dry in shade. |
General guidance only. Confirm exact care recommendations with the finished garment’s composition, construction and any functional finishes.
Industry Reference Ranges: Weight, Shrinkage and Stretch
The figures below are published industry reference ranges used across the apparel supply chain — they are not a statement of our factory’s measured performance on any specific order. Actual values vary with yarn, knit structure, dyeing and finishing, and must be confirmed on your approved production sample and test report.
Use them as a starting point when you write a tech pack or compare quotations from different suppliers. Where a test method is cited, that is the standard buyers normally specify.
| Parameter | Typical industry range | Common test method | Notes |
|---|---|---|---|
| Polyester knit weight | 120–220 gsm for performance knits and running tees; 230–320 gsm for compression leggings | ISO 3801 / ASTM D3776 (mass per unit area) | Heavier knits give more opacity and compression; lighter knits breathe better. |
| Shrinkage tolerance | Woven apparel: about 3% max; knit apparel: about 5% max (both directions) | ISO 6330 / AATCC 135, after three wash-and-dry cycles | Most buyer protocols adopt these limits; tighter limits require pre-shrunk or heat-set fabric. |
| Colour fastness (nylon & polyester swimwear) | Generally specified at grade 4 or 4–5 on the grey scale for wash and light; chlorine and seawater resistance specified separately | ISO 105 series (e.g. C06 wash, B02 light, E02 seawater) / AATCC 61, 16 | Lower grades are common on dark shades and cheap dyeings — always ask for the report, not the claim. |
| Spandex denier & content | 40D and 70D are the most common; roughly 15–25% spandex for swim, 8–20% for activewear, depending on the knit | Composition verified per ISO 1833 / AATCC 20A | Higher spandex content improves recovery but raises cost and can reduce breathability. |
| Stretch recovery | Above 90% recovery after repeated extension is a common target for fitted activewear | ASTM D3107 (fabric stretch and recovery) | Low recovery shows up as bagging at knees and seat after wear. |
| Recycled polyester | rPET can match virgin polyester on weight and performance when GSM and composition are held constant | GRS (Global Recycled Standard) with transaction certificates per batch | Ask for the GRS scope certificate and a transaction certificate for your order — a logo alone proves nothing. |
Our own factory holds BSCI, GRS and OEKO-TEX certifications. If you need measured values for a specific fabric, ask us for the test report for that article rather than relying on any published range — including this one.
Regenerated Cellulose Fibers Explained
These fibers are made from natural cellulose (wood pulp, cotton linter or bamboo) and are widely used where softness matters but cotton is not ideal:
- Viscose / Rayon — soft with a silk-like sheen; loses strength when wet, so it must be washed gently.
- Modal — made from beechwood pulp; softer and more stable than standard viscose.
- Lyocell (Tencel) — produced in a closed-loop solvent process; smooth hand, good moisture management.
- Cupro — regenerated from cotton linter; fine, soft and drapey.
- Acetate — silk-like appearance with good elasticity; generally dry-clean only.
Finishes and Dyeing: What the Terms Mean
Buyers often see finishing terms on spec sheets without explanation. The common ones:
- Mercerizing — a caustic-soda treatment that gives cotton a stable, silk-like lustre and improves strength; done once (single) or twice (double).
- Singeing — passing fabric over a hot surface to burn off surface fibres, increasing smoothness and lustre.
- Brushing / Raising / Peaching — mechanically lifting surface fibres to create warmth and a soft touch (peaching gives a suede-like finish).
- Anti-pilling — reduces the fibre tangles that form little bobbles on knitwear.
- Dyeing methods — fibre-dyed and yarn-dyed give the best colour depth at higher cost; piece-dyed and garment-dyed are cheaper with lower colour fastness.
Knitted vs Woven: A Sourcing Note
Woven fabrics are made from two sets of yarns interlaced at right angles (warp and weft) — they are stable and hold structure, typical of jackets and woven shorts. Knitted fabrics are formed by interlocking loops, which lets them stretch and recover — the norm for leggings, swim, tops and sports bras. If a design needs stretch, it is almost always knit, with spandex or an elastic fiber added.
How This Applies to Custom Manufacturing
When you brief a factory, the fiber story drives the whole spec: it sets the hand feel, the printable finish, the durability and the care label. For activewear and swimwear, we most often work with nylon-spandex and polyester-spandex, plus PBT and chlorine-resistant options for swim. For casualwear, cotton-blend fleece, jersey and French terry are common. See our activewear & swimwear fabric guide for the performance-fiber comparison, and our fabric library for grams per square meter (GSM) and stretch ranges.
Frequently Asked Questions
Which fiber is best for activewear?
For performance fit and feel, nylon-spandex is the premium choice and polyester-spandex the cost-effective one that also prints sharper. The right answer depends on your market position, print requirements and budget.
Is cotton good for sportswear?
Cotton is comfortable but absorbs and holds moisture, so it is not ideal for high-sweat performance wear. It works well for athleisure, warm-up and casualwear, often blended with polyester or a small amount of spandex.
Why is spandex added to fabric?
Spandex (elastane) provides the elongation and recovery that lets a garment stretch and snap back to shape. It is used in small percentages, usually around 10–25% in performance knits.
Which fibers resist chlorine best?
For frequent pool use, chlorine-resistant polyester and PBT outperform nylon and standard spandex, which degrade faster in chlorinated water. See our chlorine-resistant swimwear fabric guide.
How should I care for a stretch garment to protect the elasticity?
Wash cool, avoid high heat and harsh chlorine, and dry away from direct sun. Heat and chlorine are the main causes of lost stretch and shape over time.
Do you help choose fabric for a new collection?
Yes. Tell us the product, target market and performance needs, and we will recommend fibers, weights and finishes, then confirm everything during sampling.
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