Designed to feel like nothing

Smoothshell™ is a technical underwear fabric that we have developed to be exceptionally lightweight, breathable, and smooth against the skin.

Smoothshell™ consists of 88% regenerated polyamide and 12% elastane.

Smoothshell Light™, made using a finer yarn, consists of 87% regenerated polyamide and 13% elastane.

Both fabrics are built around ECONYL® yarn, transforming regenerated nylon into the most comfortable underwear in the world.

What is ECONYL®?

ECONYL® yarn is regenerated nylon made from polyamide waste. This waste includes discarded fishing nets recovered from the oceans, industrial plastic waste, as well as leftover yarns and fabric scraps.

Together with ECONYL®, we want to redefine the principles of synthetic fibre reuse. The goal is not simply to create products made from recycled materials, but products that can themselves be regenerated and recycled again and again.

This becomes possible by designing materials that can be recovered from post-consumer waste and regenerated repeatedly without compromising quality.

What does the journey of the waste look like?

• The ECONYL® reclaim managers are expanding the waste collection network, across the globe with operations in the USA, Egypt, Pakistan, Thailand, Norway, and Turkey.
• The Healthy Seas, a journey from waste to wear initiative – volunteer divers are recovering abandoned or lost ghost nets from the bottom of the seas in Belgium, the Netherlands, Italy, Greece, and Croatia.
• Net-Works, Founded by Interface with Zoological Society London, is a social initiative to empower coastal communities in the Philippines and Cameroon to collect and sell discarded fishing nets.

In the small town of Ajdovščina, near Slovenia’s capital Ljubljana, the collected waste from around the world is cleaned and prepared for regeneration. Nylon 6 is separated and recovered, while the remaining materials are directed to further recycling streams.

The cleaned nylon waste is then shredded, compacted, packed, and transported to the ECONYL® regeneration facility in Ljubljana.

Creating the miracle - 100% Regeneration

What makes the ECONYL® depolymerisation process so unique? First and foremost, its exceptionally high efficiency, meaning a remarkably high yield of regenerated nylon compared to the amount of raw waste material processed, as well as its entirely new purification method.

Unlike traditional mechanical recycling, this chemical recycling process completely removes impurities from the raw material. The result is nylon that is chemically identical to virgin Nylon 6.

Aquafil invested more than four years and over €25 million into the research, development, and construction of the Ljubljana regeneration facility.

From regenerated raw material to Nylon 6 polymers

The processes and chemical methods used to produce Nylon 6 polymers from ECONYL® caprolactam are identical to those used with virgin oil-based caprolactam. This process is known as polymerisation.

The Nylon 6 polymers produced from ECONYL® caprolactam are then further processed into textile yarns and carpet fibres at specialised production facilities.

ECONYL® yarn can be regenerated infinitely without any loss in quality.

How is Smoothshell™ created?

Everything begins with ECONYL® yarn, which is knitted into an exceptionally fine and dense technical fabric. Combined with a small amount of elastane, it creates something entirely unique: Smoothshell™.

The material is then dyed, finished, and cut into underwear. Every detail from seam placement to pattern construction is designed to make the final product feel as light and unobtrusive as possible.

The goal is not simply a good fit, but the sensation of not noticing the garment at all.

Smoothshell™ and Smoothshell Light™

Smoothshell™ is our original fabric: feather-light, breathable, and flexible for everyday use.

Smoothshell Light™ is a lighter version made using a finer yarn than Smoothshell™. It has been used in our latest women’s collection to create exceptionally lightweight, minimalist, and silky-soft products.

Both fabrics, however, are built around the same philosophy: underwear should adapt to the person, not the other way around.

Why does Smoothshell™ feel different?

Many underwear fabrics begin to feel heavy, sweaty, or restrictive during the day. Smoothshell™ was designed specifically to solve this problem.

Its exceptionally fine structure makes the fabric feel silky-soft against the skin, while elastane provides flexibility without a compressive feel. The result is a lightweight, breathable fabric that retains its shape remarkably well over time.