Developing bio-based colourants and their applications requires a multidisciplinary approach and the expertise of several research fields. In November 2019, members of the BioColour-consortium visited the research teams engaged in biochemistry, design research and biotechnology at Aalto University and VTT. Following is an overview of activities presented during that visit.
Biochemical innovations towards new color sources and technical qualities
The Aalto University Department of Bioproducts and Biosystems (Bio2) focuses on products and solutions derived from nature through green chemistry or biotechnological methods. The BioColour research team at Aalto Bio2, led by Tapani Vuorinen, focuses on the use of by-products from forest industry in colourant production. This team studies the potential of spruce and willow bark as well as lignin as a raw material for colourants giving yellow and red shades as well as a variety of browns and blacks. In addition to the extraction of natural colourants, the research also focuses on the chemical reactions of colour formation and the interactions between dye and materials. Controlling these interactions contributes the creation of target shades from individual dyes and from mixed dye sources.
In addition to coloring properties, lignocellulose isolated from wood contains many other useful properties that Monika Österberg and her team are exploring in Aalto Bio2. Lignin is known to have UV-A blocking properties. In this part of their study, the aim is to develop bio-based non-toxic surface treatments for textiles and to create functional materials with added value.
BioColour consortium members also got a chance to learn about the production of the Ioncell textile fiber, which is one of the major material innovations developed by Aalto University and the University of Helsinki. Ioncell technology utilizes an ionic liquid to dissolve cellulose from paper pulp or used textiles, which can be turned into virgin textile fibres using the dry-jet wet spinning technology. Ioncell technology has the potential to revolutionize the recycling and reuse of textiles, as well as the reuse of colourants. Accordingly sorted coloured textile waste can directly be converted into colourful fibres which need no further dyeing.
Bio-colors as a source of new aesthetics and sustainability in design
At Aalto University School of Art and Design, researchers and students explore and create the possibilities of what design will be in the future. Colour is an essential element of the materials that form our designed surroundings and a critical examination of its sources and uses in design processes enable creation of new aesthetics. The key question is what would be the colour palette based on sustainable production principles and how it would be used more widely, for example in the apparel industry. The use of bio-based dyes will not only provide new colour shades on products but also more diversity in colour stability and evenness that can be embraced to create new design features.
The Aalto Art research team led by Kirsi Niinimäki and Julia Lohmann is also examining how new biocolours and their value chains can be accepted and adopted at the level of society, businesses and consumers. By co-speculation and making the social and ecological meanings of biocolours visible through a critical approach, cultural preconditions for wider adoption of biocolours can be created.
New colourant production methods using fungi and microbes
At VTT Technical Research Center Merja Penttilä leads the team that is developing methods for the production of bio-based dyes using synthetic biology. For example, dyes produced by fungi, molds and microbes can be engineered to the desired direction and the production of potential toxic compounds can be eliminated. VTT has also good facilities and possibilities to explore scaling up dye and pigment production from microbial sources or bio-industries side-streams to meet up the requirements of industrial production. Exploring the possibilities of increasing production is – alongside new dye sources and their societal acceptance – important for aiming for wider use of bio-dyes and for the shift towards a more sustainable colourant industry.
Text and photos by Riikka Alanko, interaction coordinator