Expanding the Organic Material Evolution

Live on Kickstarter

Live on Kickstarter

WillowFlex, the World's First Flexible Compostable* 3D Printing Filament

Over millions of years, nature developed a variety of starch based elastomers. Eco-Chemistry is slowly catching up. BioInspiration’s “Beta Test” is WillowFlex for 3D Printing. After all – there is no better chemist then Mother Nature.

Why is this a game changer?

WillowFlex Filament is a step into the Organic Material Evolution – access to materials and process that follow nature’s lead – compostable, upcyclable, harmless, innovative, resilient.

Material Transparency

WillowFlex’s base component is non-GMO corn starch. This unique elastomeric bioplastic is made from compostable raw materials that have passed the U.S. (ASTM D6400) and E.U. (EN 13432) standards for compostability. <Read More about the compostability tests here>


Anyone who has tried 3D printing knows the familiar scent of melted plastic in the air. WillowFlex gives hardly any smell – but if you lean in close, you might catch a natural scent like baking bread or brewing beer.

We envision WillowFlex (and our standard Willow Filament line to come) will set a new baseline for filaments used in sensitive environments such as schools, homes and kitchen, and medical applications.

MakerBot going to Schools: http://bit.ly/1Dkcc5H

Stratasys online courses for Schools: http://bit.ly/1IG7dfX

Otelo Child 3D Printing

Image courtesy of Otelo (http://www.otelo.or.at/)

BioInspiration defines our safety requirement not only for humans but also for the environment. When your custom printed Willowflex headlamp adapter gets lost in the woods on your next camping trip – it will return to the earth without any harmful effects (in the future the electronic portion will too!). Did your daughter bury her new 3D printed sand form at the bottom of the sandbox? In a couple years it will blend right into the sand.


Bio-Inspired products have comparable qualities and often include unique advantages provided direct from Mother Nature.  BioInspiration searches out products that aren’t there only to relieve the waste stream but to improve the products themselves.

WillowFlex Cup Squeeze

  • Heat Resistance

WillowFlex is able to maintain integrity at temperatures in excess of 100 C.  Now you can print your teacup and use it to drink tea without affecting the structure. You can leave your 3D printed sandals in the sun and they won’t deform when you step into them.  We are also excited for what this heat resistance will mean for electronic applications such as flexible PV Panels.

  • Cold Resistance

Giving materials to children is a great way to test all the possible uses! Our first sample 3D Printed WillowFlex boxes have been being put in the freezer to make ice-cubes for 3 months. They continue to withstand the freezing and defrosting process and the flexible surface makes it easy to remove shaped ice cubes. The Material has been confirmed to retain its flexibility at – 15 C.  (But it might go even lower…)

  • 10 Colors to Choose From

We have selected an initial 5 Colors that will be the initial Willow Flex batch.  The other 5 will be voted on by the project bakers and be made “to Pantone color specification” by our filament producers.

Initial 5 WillowFlex Colors

Campaign Purchase Costs

Tell me more about what this compostability testing means…

The more stringent of the two criteria is from the EU (EN 13432). It states that the material can be recycled through the composting of organic solid waste (http://greenplastics.com/wiki/EN_13432) and includes:

  • A biodegradation level of at least 90% in less than 6 months.
  • Disintegrability with test material greater >2 mm less than 10% of the original mass
  • Absence of negative effects on the composting process
  • Low levels of heavy metals and absence of negative effects through a plant growth test.

The raw material from WillowFlex has additionally met the less stringent U.S. (ASTM D6400).

It is important to note that these certifications are based on Industrial Level Composting – so you should not expect the same speed from your backyard compost pile. But you should expect the same end result, the material returning to the soil.

Composting Status, 10 Months

Composting Status, 10 Months

Composting Status, 18 Months

Composting Status, 18 Months

But if it is compostable – won’t it just start decomposing?

The Composition Process only occurs when 4 criteria appear concurrently – Moisture, Microbes, Oxygen and Heat. When any one of these criteria are not met, then the material will remain stable. We are working with a base material that has been use (and remained stable) for 4 years and counting.

Steps to Decomposition

As this is a Beta – we are currently running a series of tests to see how the material responds in the following conditions and we will keep our backers updated:

  • Inside Location (Sun)
  • Inside Location (Shade)
  • Outside Location (Sun)
  • Outside Location (Shade)
  • Wet Location
  • Children’s sand-box
  • Slow Composter
  • Fermentation Composter (Bokashi)
  • Buried

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I’m ready! – but why should I choose a flexible filament?

Flexibility in 3D printing is a new road that we are all traveling together. What is most exciting about WillowFlex is that you aren’t just adding flexibility to your 3D Print, you are also adding heat and cold resistance. A good way to get inspiration is to simply look around you and see what are the items you are using already that are made from flexible plastics – And how do you want to customize them on your 3D Printer?

We expect (and will ourselves be playing in) the following product developments

  • Shoes
  • Clothes
  • Fashion Accessories, Watchbands
  • Toys
  • “Adult Toys”
  • Cups / Plates / Bowls
  • Glasses Frames, especially for children and sports
  • Custom Ice Cubes!
  • Outdoor Equipment
  • Models and Body Applications
  • Masks

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Flexible Electronics

This is a field that we think is a perfect synergy with our material and we are searching out partners to develop our material and test its response in various electrical applications.

  • Flexible PV
  • Flexible Batteries
  • Flexible Displays
  • Flexible Sensor Systems

These are all directions that are at the tipping point of feasibility.

Images used with Permission from IDTechEx (http://www.idtechex.com/)
Images used with Permission from IDTechEx (http://www.idtechex.com/)

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Who is bringing us this new material?

BioInspiration Logo_v7_50


The project was brought together by BioInspiration, a Berlin-Area company dedicated to expanding the Organic Material Evolution.

BioInspiration expands access to materials and process that follow nature’s lead – compostable, upcyclable, harmless, innovative, resilient. The Organic Material Evolution is about providing access to natural products that are equal to or exceeding the capabilities of currently produced materials. BioInspiration’s focus is bringing the nascent technologies of innovators to wider use and public awareness. BioInspiration offers material, technical and production innovations. BioInspiration emphasize direct partnerships to bring seamless integration of these innovations into products and existing production streams.

BioInspiration worked with two experienced production partners to offer WillowFlex to the world!




Green Dot aspires to improve the environment in which we live by building a more sustainable world through renewable biobased resins and promoting their use through invention, creation and research. Green Dot is a bioscience social enterprise headquartered in Cottonwood Falls, Kansas. We’re a full service bioplastics company dedicated to delivering the very best to our customers. That’s why we offer our Terratek® line of bioplastics, developed to meet the growing demand for biobased and compostable materials designed to lessen our impact on our environment. Green Dot is committed to providing sustainable materials of uncompromising quality so that everyone can contribute to a more sustainable world.


3dk.berlin, Germany


3d-k.berlin is the youngest Business Branch of BERNHARDT Plastics Preparation GmbH (with 30 years experience in plastic processing). Located in the experimental hub of Berlin, they are combining new production techniques for 3D Printing with over 30 years of professional experience in Plastic Production and Extrusion. Their 3D Print Studio is equipped with 7 different 3D Printers in order to test and develop all Filament production. Their primary emphasis is on an error-free and uninterrupted print experience – determined by the material quality and a well calibrated machine. They have already developed a PLA Filament line with over 50 different colors including Effect and Metallic Colors developed in-house. In addition, they offer color matching services to any requested Pantone® color.

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Current Status of the Project

BioInspiration has overseen the initial testing and an alpha production run of WillowFlex for our own 3D Printing tests. We have made several iterations on the formula to optimize for 3D print conditions. The base product from Green Dot has been in use for 4+ years. The formula will be used as currently developed for this campaign and improved after the initial production run and customer feedback.

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OK – I’m Convinced. How can I get started?

Step 1: Select your reward level.

Step 2: Join our Idea Community (bioinspiration.eu)

– Project is Fully Funded Here –

Step 3: Vote for the 5 Additional Colors to be produced.

Step 4: Wait for 1-2 months for production and shipping.

Step 5: PRINT!

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Material Print Settings

Extruder Temperature: 175 – 185°C

Platform: Cooled Bed

Recommended Print Speed: 50 – 70 mm/s

Filament Diameter: 1.75mm

Spool Sizes:

S- 300g    Outside ø 170 mm; Inside ø 50 mm; Height 50 mm

M- 500g-1kg    Outside ø 200 mm; Inside ø 52 mm; Height 58 mm

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Where will we go from here?

WillowFlex is the first of a series of products being developed by BioInspiration with partners around the world. Stay tuned for updates to expanded offerings in 3D Printing but also in any space that is touched by the Organic Material Evolution.

Specifically, we are currently doing production tests for a non-elastic compostable Filament that we anticipate will be available before the end of this year. We will keep in close contact with users of WillowFlex to see what additional features and requirements we need to integrate. Different levels of flexibility? Faster Print Speeds? Expanding on additional physical properties we haven’t yet discovered?

BioInspiration is also pursuing non-3D usages for the base-Material and is happy to field any questions and partnership concepts.<Email Us>


Risks and challenges

Production Verification:
BioInspiration has selected trusted partners to work with on this campaign and have completed an initial test production run with the actual end material. All Production is completed in-house in both locations (Kansas & Berlin) by teams with over 30 years experience in their field.

There is always the chance of equipment failure or similar especially when scaling production, but each location has an additional R&D production machine that can be used in the case of malfunction.

Material Formula:
We have already undergone a series of material formula revisions to customize for the 3D printing experience. This is the same formula that will be used for the final production. This campaign is simply to get to scale!

Customs & Shipping:
For backers located around the world, there is always a chance that during shipping there are delays shipping between different countries. Depending on the size of the final campaign – we may engage a second production location in the US to meet that demand.

Brian Crotty is the CEO of BioInspiration. He has been helped grow the company by applying diverse management and production skills to his interest in alternative materials and Biomimicry. He also serves as an advisor to DaVinci Global, a think tank concentrating on investment in biomimicry.