The Bio-Based Collection

The Bio-Based Collection

This collection of knee highs are made in bio-based nylon, made from castor plants (sv: ricinplanta).

" We have been working on this collection for a long time, so it's exiting that the knee highs are finally here. It has been a process of development with research, design, finding the material, and then to design packaging and to create it.

It is so nice to see it all come together into one whole, finished product. It's very interesting working with newly developed materials. The material is not just bio-based, it has so many features that pushes the boundaries of what nylon can be. So it is very exiting to finally have them in store.

C. Renhuldt - designer & founder

 The material's features are

  • soft with an excellent elasticity
  • light, weights less than regular nylon
  • dries faster than regular nylon
  • has thermal insulation properties
  • has odor control features, with a built-in bacteriostatic in the fibre, not an added. This means that the feature will stay with the product for its full lifetime, and not be removed in washes.
  • The knee highs are made in bio-based Italian nylon (92%), and elastane (8%).
  • The material is OEKO-TEX 100 and DIN CERTCO: BIOBASED >85% certified.
  • The bio-based Italian nylon is 100% bio-based.

Read more about the bio-based nylon fiber Evo by Fulgar here:

About castor plants

They live in areas of almost desert, so they do not take feeding ground from other animals or plants. The castor oil (ricinolja) comes from the castor seed, that grows within the seed capsules. They grow fast, has big leafs and can reach sizes as big as a small three. Castor oil have been used for different things through out history, such as medical uses and as motor lubricants due to its great heat resistance. 

About the packaging material

Bamboo paper is an eco-friendly and sustainable alternative to paper made out of trees. Bamboo grows faster than trees, and does not have to be cut down as trees, but can be cut and then regrow. Bamboo paper has a lower carbon emission than wood.

The dyeing of Black and White knee highs

The black and white knee highs are dyed in Italy. The knee highs are OEKO-TEX 100 class 2, and DIN CERTCO: BIOBASED >85% certified. 

The dyeing of Green, Navy and Soft Yellow knee highs

These colors are dyed by hand at the 1800 studio in Stockholm, with high quality sustainable dyes that are non-toxic to the groundwater. The knee highs are DIN CERTCO: BIOBASED >85% certified. 

The different certifications

OEKO-TEX 100: 
This certificate approves products in regard to chemicals used during production, and measures if there are chemicals in the product after production. The fabric/knit is measured as well as threads, buttons and trims, the full finished product must be approved for this certificate. The organisation is based in Switzerland. 

This German standard measures the bio-based content in a material, it has to be over 85% to be approved for this certificate. The bio-based nylon fiber is 100% bio-based, made from castor plants.
The material Evo by Fulgar's certificate:


About the product design

The knee highs are designed by fashion designer I.C. Renhuldt in Stockholm, and produced in Italy. The triangle on the side is building on 1800's previous collection with minimalist geometrical shapes. The seam at the toe is neat and the elastic band is flat knitted, for enhanced comfort.

About the packaging

The packaging is illustrated and designed by I.C. Renhuldt in Stockholm, and produced in Italy. It is made in soft matte aquarelle bamboo paper, with embossed black logo and illustration of knee high at front. The gouache illustrations are of castor plants, their leaves and seed capsules.

Answers to your questions:

- Are there any silver thread in the nylons to provide the odor control feature?

Answer: There are no added anti-odor substances in this product, such as silver thread.

If you have questions, feel free to email me at and I will do my best to respond them accordingly.

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