Ecologically colored PLA

Kristof Deruyttere is a designer and community member, after an Ulti-evening talk he got to test some ecologically colored PLA here are his findings. -Alexander Baloche

We are one step closer to printing in fully ecological filament and thereby getting rid of the industrial chemical colorings. A team of grad-students at the Avans school in the Netherlands have been researching how that could work. Two of those Grad students are Max Kuiper & Jakko Theeuwens, they have given me some PLA  samples with natural coloring to test, The colors being Kurkuma  & Rubia. Both start with the same basic PLA resin and are then colored with these natural dies. The difficulty is in finding the right proportion of the filament and coloring.

Kurkuma is a herb used for coloring spices such as curry and is widely available to the public. Rubia is a bit harder to get a hold of because its made out the color-chemical found in carrots, the natural color is somewhere between cola and bronze.

Kurkuma Powder

Different shades of Rubia

And now for the more technical part of the tests:

4043D PLA Rubbia or Kurkuma +/-2,7mm

I printed the octopus 

                                                         These are my KISslicer settings:

                                                                                    Both are made with the same PLA resin, so settings where equal.                                           Temperature printing: 210°C

Judgment: The Rubia filament was dark but transparent while Kurkuma filament had little bits and pieces in it and some small air-bubbles , but this actually did not seem to hinder printing. While printing there were remarkably few strings, even at higher speeds. The octopus required a lot of retractions , but the material didn’t seem to have problems with that at all, tough this might depend hugely on the build-quality of the Ultimaker. Somehow I was expecting to smell carrots and curry but luckily the prints are odorless (well except PLA-smell). For starters, the first layers sticked very well to the scotch tape and all it needed was a little skirt.

Printed with Rubia PLA

I set the fill  rate for the octopus to 5% and was curious to see how this would turn out:

• 100% speed OK, fill 5% hanging down
• 125%  speed OK, fill 5% hanging down
• 150%  speed OK
• 175% speed better!, fill 5% printed in straight lines like a spiderweb
• 200% speed, Even better!, fill 5% printed in straight lines like a spiderweb

While printing the filament loses most of the transparency,  but the color stays identical.

Printed objects in Kurkuma color reminds me of a well spiced rice-dish, but when looking at it from a distance it’s closer to gold. This filament is made with supermarket-grade Kurkuma and has these tiny pieces in it, which gives it a really nice gloss and reflection though that isn’t very helpful when printing sculptures where you rely mostly on the shadows the shape casts.

Objects that will really be great with this? I am going for a golden Louis14-style (Google:’palace of Versailles’) , think about treasures, jewelery, golden cups or grails.etc.                                                                                                                                                                  As for the Rubia, well it has this shiny bronze /caramel look to it, but I can’t really point out any real specific purpose for this color. Vases should look awesome  due to the mystique radiance it gives of.

How will this continue? The grad students will publish their results for the final exam and further contact some companies to see if these great filaments can make it to the public. But wait there’s more, next year another group of students are going to pick up with this research and continue to investigate  and develop these products.

-Kristof Deruyttere