What’s the best material for underwear?

A bra consists of many different pieces and several different materials that in combination provide shape, support and comfort for the wearer.

Textile fibres are split into two groups, natural and man-made. Natural fibres are in turn sub-divided into plant fibres (cotton, linen, hemp) and animal fibres (wool, silk). Within man-made fibres there are two sub-groups, regenerated fibres from natural sources (for example viscose, bamboo, modal) and synthetic fibres that are based on man-made organic polymers, usually oil. Examples of synthetic fibres are polyester, elastane and polyamide.

All textile fibres have different characteristics with advantages and disadvantages. There is no one textile fibre that is best for all types of underwear. Any one bra is comprised of several different types of materials; since the different parts of the bra have different functions they require materials with different characteristics.

Underwear made from cotton and other natural fibres

Natural fibres come from organic sources and can be divided into two groups, plant fibres such as cotton, linen and hemp and fibres that come from the animal kingdom such as wool and silk. Natural fibres don’t need to be processed or broken down but can be spun directly into a yarn that can then be woven or knitted into fabric. The natural fibre that is most suitable for and therefore also the most commonly found in underwear is cotton. Linen is not particularly suitable for underwear because it shrinks and is inelastic. Underwear made from silk fibres, or silk as the final material is known, is beautiful and comfortable to wear but the material needs to be handled carefully and the garments are expensive and delicate.

Wool is used in many types of garments, but for base layers it’s most commonly used for sports activities since it’s warming and can absorb up to 30% of its weight in moisture without it feeling wet. However, it is not usually used in everyday underwear like a bra since it’s not particularly easy to look after and needs to be washed at low temperatures.

Cotton underwear is perfect for everyday wear because it is durable and easy to look after. Pictured are Lovely Lace bra and panties.

Of all natural fibres, cotton is the most suitable for underwear. Cotton is durable, easy to look after, easy to dye, has a long lifespan and can withstand many washes. The cotton fibres actually become stronger when they’re wet than dry. It doesn’t attract odours in the same way as synthetic materials (think about how certain garments attract odours when they’ve hung unused in the wardrobe for a while). Cotton is comfortable to wear and perfect for sensitive skin, which makes it a natural choice to use for base layers like panties, camisoles, bras, bodies and nightwear.

The Broderie Anglaise bra is made from 83% cotton if you combine all the pieces of the garment. The material in the cups is 100% cotton.

The greatest benefit of cotton is that like all natural fibres it’s very breathable, which makes it an excellent material to wear on warm days. Its biggest disadvantage is that it requires a lot of water to cultivate. Cotton absorbs moisture and will stay dry as long as the moisture evaporates faster than the material can absorb it. For that reason, it’s not the best material for sport or those who sweat a lot; for those cases it’s better to use a bra that is made from a synthetic functional fabric. Consider also that cotton panties only allow the body to breathe if your trousers are also made from a breathable material. Cotton is not as elastic as synthetic fibres, which means that the parts of the bra that require elasticity, for example the back, need to contain a certain amount of synthetic fibres.

When we line a cotton bra we always use cotton lining, for example on the bra STAR.

Tip! If you’re looking for a cotton bra, buy an unpadded one since the padding in the innermost layer of the cups is made from a synthetic material and can therefore get very warm. Padding is rarely breathable, unless it’s a special functional material like spacer for example. If the cups are lined, check that the lining is also cotton and not synthetic. If both the outer material and lining are cotton then the cups will breathe. When we line our cotton bras we always use a cotton lining with just that thought in mind.

Underwear made from synthetic fibres

Synthetic fibres are made via a chemical process that uses oil as the raw material. There are many different types of synthetic material with even more application areas. The most commonly used for underwear are polyester, polyamide and elastane.

Polyester is the most common synthetic fibre. It is heat and colour resistant, dries quickly, doesn’t crease and shrinks less than for example cotton fibres. Polyester is also more elastic than cotton. It is more durable and is often used in functional fabrics and sports bras since it doesn’t hold moisture. Polyester fibres wick moisture away from the body but instead of it being absorbed by the material it evaporates. The result is that the material feels dry.

Sports bras made from functional fabrics with synthetic fibres that don’t absorb moisture. Pictured is Exhale sports bra in 69% polyamide, 18% elastane, 13% polyester.

When polyester is dyed, the fibres hold their colour better than for example cotton, which can fade when it’s washed. Polyester burls easily, so it’s good to mix it with other fibres. There’s a big difference in quality between different polyester fabrics. Polyester is versatile and can be used for a wide variety of different designs such as satin, charmeuse, chiffon, etc.

Another popular synthetic fibre used in underwear is polyamide. It is one of the strongest of all raw textile fibres, even when it’s wet, and is much more elastic than natural fibres. It is easy to look after, rarely creases and doesn’t burl unlike polyester and cotton. It feels soft against the skin, is breathable and has good resistance against moisture and sebum. It is more resistant to moisture than polyester but takes longer to dry.

The mixture of polyamide and elastane is very popular in underwear for its soft and elastic feel. Pictured here is Cool Sensation in 81% polyamide, 19% elastane.

It’s common to combine both polyester and polyamide fibres to take advantage of the best qualities of each fabric. That way you get a very strong material with many benefits.

The Summer series underwired bra and panty in charmeuse material and guipure lace made from a polyamide-polyester-elastane mix. Polyester and polyamide both hold their colour and don’t fade in the wash.

Elastane is a polymer fibre that is used in materials that require lasting elasticity and won’t lose their shape when they wear out. It’s common for a small amount of elastane to be mixed into fabrics that are meant to fit tightly on the body but still be comfortable, for example the back of a bra.

The diamond-patterned material in Diamond panty and bra is a high-quality cotton-Lycra blend with a comfortable elastic fit. The under cups are 100% cotton. Combined, all the parts of the bra consist of 34% polyamide, 30% cotton, 20% polyester, 16% elastane.

In the USA elastane is known as Spandex, but in Europe the name elastane is used. Lycra and Dorlastan are registered trademarks of elastane fibres. Lycra can stretch up to six times its length and return to its original size without losing its elasticity.

Underwear made from regenerated fibres

Regenerated fibres, like synthetic ones, are man-made fibres that are produced through a chemical process using the natural source of cellulose in trees. The process is conducted in a closed system so most of the chemicals used can be recycled, but the process of turning cellulose into textile fibres is very resource intensive. There’s also a risk that the raw materials are extracted from non-sustainable sources, contributing to deforestation. The oldest regenerated fibre is rayon, which is now most commonly known as viscose. It was previously referred to as artificial silk or nitrate silk. Viscose is very soft and comfortable to wear but very resource intensive to produce. Modal is made from the cellulose pulp from beech trees. This material is soft at the same time as being stable, strong and able to maintain its shape. It also doesn’t shrink in the wash. Underwear made from modal is very unusual, even though modal fibres are well suited to, for example, panties, they’re therefore quite expensive compared with cotton and polyester alternatives. A regenerated fibre that has gained popularity in recent years however is bamboo. Bamboo fabrics are soft and breathable but tend to lose their shape after a while and therefore aren’t optimal for garments that need to fit tight against the body. However, it’s excellent for nightwear and camisoles.

Nowadays, as part of sustainable development, there are environmental certifications and trademarks that guarantee the regenerated fibres used are extracted from sustainable forests. One example is Tencel, a trademark for the regenerated fibre lyocell, which comes from sustainable forests and is traceable through every stage of the manufacturing process. The downside is that Tencel is expensive and therefore demand is low.

Why mix materials?

There are many advantages to mixing different textile fibres in one material. Mixing polyester fibres with cotton, for example, produces a final material that has better elasticity, holds its shape and colour better and shrinks less than a material that is 100% cotton. It is also less prone to burling than pure polyester. A bra needs to have a band that is very elastic and doesn’t lose its shape when it wears out. That’s why there’s elastane in most materials that are used for bands.

The band on a cotton bra always contains elastane to allow it to maintain its elasticity. Pictured is Lovely Lace in 61% cotton overall.

A bra consists of around 35 different parts, from the cups, lining and padding to shoulder straps, elastic, front panel, wings and back. The elastic, shoulder straps and band are usually not made from 100% cotton even if the cups are, which is why a cotton bra rarely contains 100% cotton. The material composition on the care label is always the average of all the different fibres included.

Polyamide/elastane is very popular and good quality for underwear that isn’t cotton. Many materials that are made from synthetic fibres, like Satin or Charmeuse for example, provide a luxurious feel and appearance with their beautiful, glossy lustres. Pictured above is SUMMER panty in a polyamide-elastane mix. The different parts of SUMMER with underwire are made from a polyester-polyamide-elastane mix, with cups in stiff charmeuse fabric and guipure lace that provide excellent support to the bust.

Fabrics and structure
You can make many types of fabrics from different textile fibres, each with its own texture and appearance. Many women love the everyday feel that a cotton bra provides, whilst others prefer the more luxurious and elegant look of a glossy material. Today there’s underwear for all tastes. Satin, for example, is a tightly woven fabric with a glossy front and matte back. It can be made from several different fibres. In the past it was usually silk, but nowadays satin is most commonly made from polyester when it’s used for underwear.

"Many women love the everyday feel that a cotton bra provides, whilst others prefer the more luxurious and elegant look of a glossy material."

The Rose bra with charmeuse on the under cups and embroidered upper cups gives an elegant and luxurious impression.

Charmeuse is a stiff satin-woven fabric with a semi-glossy front and matte back. It feels pleasant against the skin and the texture gives the garment an exclusive feel. It’s perfect to use on the cups where its stiffness and stability provide good support. Charmeuse was traditionally made from silk, but now it’s more commonly made from polyester fibres.

The Hold Me body made with leaf-patterned knitted jacquard and flower-patterned lace. Both lace and jacquard are made from soft polyamide-elastane.

Jacquard is always patterned, but rather than being printed onto the fabric the pattern is part of the weave itself. Jacquard is a technique and can be made from nearly any type of yarn, like for example cotton, silk, polyester and acrylic. Jacquard can be woven with different colour threads to form a pattern or made from a single colour that creates a ‘raised’ pattern.

Basic panties with a wonderful micro-fibre quality in a polyester-polyamide-elastane mix.

Underwear made from microfibre is light, flexible and provides an incredibly soft feel against the body. Microfibre is an ultra-fine synthetic fibre that is finer than 1 denier. Microfibre quality is normally made from polyester or polyamide. Micro-quality panties have the feeling of a second skin.

Mesh can even be patterned, like this one we’ve used in our sports bra Exhale.

In bands, it’s common to use a fine elastic material known as mesh. There are many different types of mesh, some are firmer and others softer. Mesh has a fresh and airy feel. It’s common to use mesh in sports bras as well as in bands for everyday bras. The mesh that’s used in sports bras doesn’t bind moisture. Another type of fine material is powernet, which is commonly used to line underwear and swimwear to give them greater strength. It’s popularly used to reinforce the front panel of a body or of a panty girdle for example.