Camelina As A Binder - From The Field To The Paint Can - Malerblatt Online

When the binder for a building varnish grows in the field - for most people it sounds like a fantasy story. But it is - at least in part - already a reality. At the paint and varnish manufacturer Caparol, the camelina has found its way into the recipes of some varnishes and glazes.

Author I Photos: Susanne Sachsenmaier-Wahl

Dr. Aaron Breivogel, who is responsible for the project “Sustainable wood finishing products based on camelina” in DAW research and development, explains: “Camelina is so rare today that it is on the red list of endangered domestic crops in Germany.” Camelina is an old crop, belongs to the cruciferous family. Camelina suppresses the growth of weeds with its leaf rosette close to the ground. This reduces the use of crop protection agents when camelina is grown as a mixed crop with other crops. "In addition, camelina increases biodiversity and provides food for endangered insect species, since it blooms yellow at a time when the flower supply of conventional agriculture is low," adds Dr. Aaron Breivogel. And "by the way" these insects destroy plant pests.

Camelina instead of oil

For the DAW, to which Caparol belongs, these were good reasons to rely on the production of a paint binder based on camelina. In addition, the flax yolk is grown together with pea plants and is therefore not in competition with food production. Rather, mixed crop cultivation increases the total yield of the area and strengthens the ecosystem, explains Dr. Breivogel: "The pea plants can grow up on the camelina, which has a positive impact on their growth." The Federal Environment Ministry is promoting the DAW project, which farmers want to encourage farmers to switch from pea monoculture to mixed fruit cultivation and build the necessary sustainable value chain funded in the federal program "Biodiversity" until 2022. It is supervised by the Federal Agency for Nature Conservation (BfN). Compared to pure pea cultivation, all farmers (despite the persistent drought in summer 2018) were able to record higher yields in mixed fruit cultivation, while the use of crop protection products was lower. As part of the project, a study on biodiversity in the fields is being carried out. The biologist Dr. Stefanie Göttig examines the biodiversity of insects in the mixed crop fields over a period of three years and compares them with pea monocultures. Stefanie Göttig examines the biodiversity of insects in the mixed crop fields over a period of three years and compares them with pea monocultures. Stefanie Göttig examines the biodiversity of insects in the mixed crop fields over a period of three years and compares them with pea monocultures.

From seeds to binders

After the linseed yolk seeds have been separated from the much larger peas, they are pressed in an oil mill. The resulting press cake does not end up in the waste. It can serve as a high-quality animal feed.

However, camelina oil is of interest for paint production. This is used to produce a binder that serves as a component of wood finishing products. The proportion of renewable raw materials in the binder is 50 percent for the water-borne PU varnish "PU-AlkydGeo", and 67 percent for the "Holz-ÖlGeo". This can significantly reduce the use of fossil raw materials. A “green washing”, ie a PR gag, in which Caparol wants to put on a “green coat”, cannot be said, emphasizes Aaron Breivogel. "Only products in which at least 50 percent of the raw materials in the binder are renewable are included in our geo-concept."

Testing the new paints

From an ecological point of view, the decision for a product from the Geo line always brings a profit, plus there is a good conscience for the customer. But what about the quality of the new paints and glazes? How do they fare in terms of processing, flow and durability? The Malerblatt wanted to test that for you. So I put on my white coat one more time and met the technical product supervisor and master painter Yannick Heil in the application technology department at Caparol.

Yannick Heil first presented me with the products that were to "compete": the water-borne varnish "PU-Alkyd Geo", the water-borne acrylic varnish "Capacryl PU-Satin" and the aromatic-free alkyd resin varnish "Capalac silk matt varnish". When asked how this selection came about, Yannick Heil explains: "The new geo-varnish somehow lies between these two conventional products." Because of its water-based formulation, it is more comparable to "Capacryl PU-Satin" in terms of properties but with the solvent-based "Capalac". Here, Yannick Heil, for example, cites the slight yellowing tendency of the innovative geo-lacquer, which is due to the oily binder.

Before I can finally reach for the brush, Yannick Heil applies the three varnishes to contrast cards. Based on these test areas, we compare the opacity and the course. In terms of opacity, all three products do very well, I can't make a difference. When it runs, the solvent-based varnish is slightly ahead. With the role order, however, there should be hardly any difference. Then finally I can swing my brush myself - and I am pleasantly surprised: my favorite when it comes to processing is the new paint! It can be applied very smoothly, but the acrylic paint feels a little tougher. Yannick Heil confirms this: "The geo-product has a longer open time than PU satin." Finally, I sniff the lacquered surfaces. While the solvent-based varnish performs significantly worse in terms of smell, there is hardly a difference in the water-based products. Both are pretty odorless, I think I can guess a touch more solvent with the geo-varnish.

New generation of glazes and oils

For the glazes, which I then test on wooden boards, the test result is very similar to that for the paints: As a processing favorite, I again choose the new product (no, I was not bought by Caparol!) Because it literally “slips” over the wooden surface, while the competitor's water-based Capadur DecorLasur draws significantly more and is tougher. The solvent-based Capadur UniversalLasur gets a point deduction from me because of its smell. Since it is only approved for outdoor use, this should not be too important; However, it is not pleasant for the processor.

What makes me a little puzzled is the fact that the new geo-glaze is fungicidal. Isn't that a contradiction in terms of an ecological product? Aaron Breivogel initially agrees with me. Of course, fungicides are a burden on the environment. But he adds: "The bottom line is that thanks to the added fungicides, the product is more sustainable and therefore ecological, because the wood protected with the glaze lasts longer and consequently fewer trees have to be felled." You have to be open to compromises …

Finally, I can test the new geo-wood oil. I am surprised when I open the can: At first glance, the water-dilutable decoration and maintenance oil for wooden components in the garden area (garden furniture, fences, pergolas, etc.) looks like chocolate pudding. Stingproof, so to speak. After briefly stirring with the stirring stick, the consistency soon liquefies and the oil can be easily applied with a brush. As with other oils, it is advisable to remove the excess material after a short flash with a lint-free cloth. In this way, the production of seamless surfaces is almost child's play.

Practical

My conclusion after visiting the workshop in Ober-Ramstadt is clear: the new geo-lacquers and glazes are absolutely practical and are in no way inferior to conventional products in terms of quality and processing properties. And if, as a painter, you can also protect the environment and resources when refining and protecting wooden surfaces, it certainly doesn't just make the customer feel good.

It would therefore be desirable to expand the product range from renewable raw materials. Caparol brand manager Wolfgang Hoffmann is confident: "The camelina project has succeeded in combining quality and ecology and thus providing craftsmen with high-quality products for customers who want to act sustainably and conserve resources," he says. "For Caparol, this is a further step in expanding the range in terms of renewable raw materials."

Further information on the CapaGeo product family:

bit.ly/2NXbWBn

PraxisPlus

With the project "Sustainable wood finishing products based on camelina", the DAW won at the GreenTec Awards 2018 in the category "Building & Living". The world's best projects, which are committed to environmental and resource protection and make a sustainable lifestyle suitable for everyday use, were awarded in a total of twelve categories.