Introduction to Technical Fabric Knowledge

Every successful swimwear founder eventually discovers one key truth: understanding fabric terminology is non-negotiable. Fabric knowledge affects product quality, fit, durability, and customer satisfaction. Whether you're developing your first collection or scaling production, getting familiar with technical fabric language will help you communicate clearly with suppliers, compare materials confidently, and avoid costly mistakes.

In this guide, you’ll learn 10 essential technical fabric terms used across the swimwear manufacturing industry. These terms form the foundation of material selection and determine how your swimwear performs, stretches, and lasts over time.

Technical Term #1 — Denier (Fiber Thickness)

Denier measures the thickness of individual fibers within the fabric. Lower denier means a smoother, thinner feel; higher denier results in firmer, stronger fabric.

How Denier Affects Swimwear Performance

• Higher denier = more durability

• Lower denier = softer and more lightweight

• Impacts drape, opacity, and compression

Most premium swimwear fabrics fall between 70D–140D, depending on the intended use.

Technical Term #2 — GSM (Grams per Square Meter)

GSM is a measurement of fabric weight and density. Many founders overlook GSM, but it plays a critical role in durability and opacity.

Ideal GSM for Swimwear Fabrics

• 180–240 GSM: Standard fashion swimwear

• 250–300 GSM: Sculpting, compression swimwear

• 300+ GSM: High-support or athletic swimwear

Higher GSM often means better shape retention.

Technical Term #3 — Warp-Knitting

Warp-knitting is a technique used in technical swimwear fabrics—especially Carvico fabrics—designed for high elasticity and long-term durability.

Benefits of Warp-Knitted Swimwear Materials

• Excellent stretch in multiple directions

• Won’t warp or sag when wet

• Ideal for active, performance, or athletic swimwear

This is one of the most common constructions for premium swimwear textiles.

Technical Term #4 — Elastane Percentage

Elastane (also called Lycra or Spandex) is the stretchy component of swimwear. The percentage of elastane determines how flexible and supportive the fabric feels.

• 10–15% elastane = medium stretch

• 20–25% elastane = high stretch (most premium swimwear)

• 25–30% elastane = shaping or compression fit

If the elastane content is too low, the fabric may feel stiff or lose its shape over time.

Technical Term #5 — Chlorine Resistance

Chlorine is one of the harshest chemicals for swimwear. Chlorine-resistant fabrics maintain color, structure, and elasticity even after repeated pool exposure.

Swim founders creating lineups for training, sport, or daily pool use must prioritize chlorine-resistant technical fabrics.

Technical Term #6 — UV Protection (UPF Ratings)

UPF (Ultraviolet Protection Factor) measures how much UV radiation a fabric blocks.

• UPF 30 = good protection

• UPF 50+ = excellent protection

UPF ratings are increasingly important as consumers become more health-conscious and expect their swimwear to protect their skin.

Technical Term #7 — Pilling Resistance

Pilling resistance determines how well the fabric withstands abrasion and friction. High-quality swimwear fabrics undergo standardized pilling tests to ensure a smooth appearance even after long wear.

Technical Term #8 — Colorfastness

Colorfastness measures how well a fabric holds dye when exposed to:

• Sunlight

• Chlorine

• Saltwater

• Sunscreen

• Repeated washing

Poor colorfastness leads to fading, patchiness, or discoloration—common issues in low-quality swimwear.

Technical Term #9 — Compression Power

Compression indicates how much support and shaping a fabric provides. Higher compression improves body sculpting and enhances garment stability.

Founders designing performance or sculpting swimwear should look for:

• High GSM

• Higher elastane percentage

• Strong warp-knitted structure

Technical Term #10 — Regenerated Nylon (Example: Econyl)

Regenerated nylon is a recycled, sustainable version of traditional nylon. Econyl is the most well-known example, created from ocean waste, fishing nets, and industrial nylon.

Why Recycled Nylon Matters

• Reduces environmental impact

• Performs identically to virgin nylon

• Supports circular fashion

• Boosts brand value for sustainability-minded consumers

More founders than ever are turning to regenerated nylon for its high quality and eco-friendly reputation.

How Founders Can Use These Terms When Working With Manufacturers

Understanding technical terminology helps founders:

• Request accurate fabric specifications

• Ask informed questions

• Compare suppliers effectively

• Avoid unsuitable fabrics

• Ensure final production matches their vision

Key Questions to Ask a Supplier

1. What is the GSM of this fabric?

2. Is it warp-knitted or circular-knitted?

3. What is the elastane percentage?

4. Does it offer chlorine and UV resistance?

5. Is the fabric tested for pilling and colorfastness?

6. Do you offer regenerated nylon options like Econyl?

FAQs About Technical Swimwear Fabrics

1. Are higher GSM fabrics always better?

Not always—higher GSM means more support, but lighter GSM gives better comfort and flexibility.

2. How do I pick the right elastane percentage?

Consider your design: bikinis need flexibility; performance suits need tighter support.

3. Is warp-knitted fabric better than circular-knitted fabric?

For swimwear, yes—warp-knitting provides more stability and longevity.

4. Why do some swimsuits fade quickly?

Low colorfastness or lack of UV protection.

5. Is recycled nylon suitable for all swimwear styles?

Yes, regenerated nylon offers excellent stretch, durability, and sustainability.

6. What fabric features matter most for premium brands?

Chlorine resistance, UV protection, compression, and pilling resistance.

Conclusion

Knowledge is power in swimwear manufacturing. Understanding technical fabric terms empowers founders to make confident decisions, improve product quality, and build long-lasting relationships with suppliers. Whether you're selecting regenerated nylon, evaluating compression levels, or comparing GSM values, these terms will guide you toward creating high-performance, sustainable swimwear that stands out in a competitive market.