Underwear Materials and Fabrics

Underwear fabrics including cotton, modal and microfibre

Underwear Materials and Fabrics

Cotton, modal, bamboo and performance fibres explained

OD's Designer Clothing · Knowledge Hubs

Fibre is the single biggest driver of how underwear feels, breathes and lasts. This hub explains the natural, soft-touch and performance fabrics used across our range, so you can choose the right material for comfort, coolness or sport.

Natural fibres

Cotton

The everyday standard -- soft, breathable and easy to wash.

What it is

Cotton is a natural fibre valued for softness and breathability, and combed or long-staple cottons give a smoother, stronger yarn.

Why it matters

It is the default underwear fibre for all-day comfort, though it holds moisture more than performance fabrics.

Stretch Cotton

Cotton blended with elastane for shape retention and fit.

What it is

Stretch cotton adds a small percentage of elastane to cotton so the fabric flexes with the body and springs back.

Why it matters

It keeps the soft feel of cotton while holding its shape and resisting bagging, the most common modern blend.

Merino

Fine wool that regulates temperature and resists odour.

What it is

Merino is an ultra-fine wool that feels soft next to the skin and naturally manages warmth and moisture.

Why it matters

It keeps you warm when cold and cool when warm and resists odour, making it excellent for base layers and travel.

Soft-touch fibres

A silky, breathable fibre made from beech wood pulp.

What it is

Modal is a regenerated cellulose fibre spun from beech, known for a smooth, silky handle and good breathability.

Why it matters

It feels softer and cooler than standard cotton and keeps its softness after washing, a premium underwear choice.

Bamboo

A soft, breathable viscose fibre derived from bamboo.

What it is

Bamboo underwear is usually a bamboo-derived viscose, giving a very soft, smooth and breathable fabric.

Why it matters

It offers a soft handle and good moisture and odour control, popular for a cool, comfortable everyday feel.

Performance and stretch

Microfibre

Ultra-fine synthetic yarns for a smooth, quick-drying feel.

What it is

Microfibre is a very fine synthetic yarn, usually polyamide or polyester, knitted into a smooth, lightweight fabric.

Why it matters

It is light, quick drying and no-show under clothing, common in sport and slim-fit performance underwear.

Performance Fabrics

Engineered blends built for wicking, stretch and support.

What it is

Performance fabrics blend synthetics and elastane, often with wicking or anti-odour finishes, for active use.

Why it matters

They move sweat, stretch in every direction and hold their shape, the fabric of choice for sport and base layers.

Elastane

The stretch fibre blended in for fit and recovery.

What it is

Elastane, also sold as Lycra or spandex, is a highly elastic fibre added in small amounts to give stretch and recovery.

Why it matters

It is what lets underwear move with you and spring back to shape, present in almost every modern pair.

Recycled Fibres

Yarns spun from recycled materials to cut waste.

What it is

Recycled fibres such as recycled polyester or nylon are spun from post-consumer waste rather than virgin resources.

Why it matters

They lower the footprint of performance underwear while matching the feel of conventional synthetics.

Natural fibres

Mercerised Cotton

Cotton treated for extra strength, sheen and smoothness.

What it is

Mercerised cotton is treated under tension in caustic soda, strengthening the fibre and giving a subtle sheen.

Why it matters

It feels smoother and holds colour better than standard cotton, used in premium vests and undershirts.

Frequently asked questions

Is cotton or modal better for underwear?

Cotton is soft, breathable and hard-wearing, while modal feels silkier and cooler and keeps its softness after washing. Modal is the more premium, smooth option, while cotton is the durable everyday standard.

Why does underwear contain elastane?

Elastane, also sold as Lycra or spandex, is a stretch fibre added in small amounts so the underwear moves with you and springs back to shape rather than bagging. Almost every modern pair contains a little.

Is bamboo underwear good?

Bamboo underwear is usually a bamboo-derived viscose that gives a very soft, breathable fabric with good moisture and odour control, making it a comfortable choice for everyday wear in warmer conditions.

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