The structure of birds in feathers allows for the creation of multi-colored plumage. This could be commercially viable, according to scientists at the University of Sheffield, England and the Institut Laue-Langevin, France. Structure is what birds use to create their unique colours, and not pigments or dyes. Tunable nanostructures allow the jay to change its feather colour in a manner similar to one human hair. Professor Andrew Parnell of the University of Sheffield’s Department of Physics and Astronomy and his colleagues believe that synthetic structural colors will soon be available. These colours would not fade like dyes and pigments and can easily be used as clothes and paints. The colours of a jay’s feather are determined by how small the holes in it. b) A Eurasian Jay (Garrulus glandarius). Cross-sectional view of the feather barb of Jay. d) & e), Optical microscope images of the region of light-blue – these boundaries are normally visible in reflected light. (Image: www.nature.com. Image (b) Credit to Luc Viatour. The discovery was published in Nature Scientific Reports, an academic journal. To examine the white and blue feathers, they used Xray scattering from the European Synchrotron Radiation Facility in France. The birds have remarkable control over their feather colors. They showed remarkable control and sophistication when producing different colours. Instead of using dyes or pigments that fade over time, birds create brightly-coloured feathers by finely controlling changes to their nanostructure. Researchers believe this is how jays recognize each other. A jay can create a variety of colors along a single feather barb. It is similar to having multiple colours on one strand. A nanostructured, spongy, keratin-based material is what the jay’s feather looks like. It can go from ultraviolet through to blue, and even white. This material is exactly the same material that our fingers and hair are made of. A scanning probe image showing the Jay’s feather’s’sponge’ structure, which is responsible for its optical properties. b) Measured reflectance of different areas in a Jay feather covert. Image: www.nature.com. Tiny holes can determine feather colours. Scientists discovered that jays have incredible control over how large the holes are in the spongy structure. They also fix them at specific sizes that determine which colour is reflected off the feather. The size of a hole determines how light scatters from feathers. White is created by the wider wavelength reflectance, meaning that the holes are larger. Blue is a more compact and smaller structure. The feathers would soon lose their colours if they were made from pigments taken from birds. There are some birds with extraordinary colours. They are not due to pigments or dyes. It depends on the size of the light reflecting through the tiny holes in the feathers. Birds do not go gray like mammals that have hair. However, nature created a system of permanent colouring for birds by using structural modifications. Birds, unlike dogs and humans who rely on hair pigments for colour, do not go gray as they age. As we get older, our pigment production decreases. This is why grey hair develops. Dr. Parnell stated that while conventional wisdom held that it was impossible to control light with materials, this discovery suggests that we might be able in the near future to create synthetic long-lasting colour coatings. It is how the nanostructure is made and controlled – by changing the density and size of the holes within the sponge-like structure – which determines the colour that is reflected. As our skin ages, pigment cells in our hair gradually decrease in number. Hair produces less pigment. Pigment is not used by birds for colouring their feathers, but it’s used by mammals for hair. Current technology can’t make color with such precision and control – so we use pigments and dyes. We now have the knowledge to create new fabrics, such as paints or clothes using nanostructuring techniques. This could mean that, if you create a red jumper with this technique, it will retain its colour and not fade in wash.” Daragh McLoughlin of AkzoNobel’s Material Science Research team explained that AkzoNobel is the maker of Dulux paint. “We aim to stimulate and encourage the development of sustainable products with eco-premium advantages at AkzoNobel. The exciting insight we have may allow us to discover new ways to make paints that last longer and are brighter, fresher, and less carbon-intensive. The University of Sheffield’s Dr. Adam Washington said that the research answered some of the most fundamental questions about certain colours. “The research also addresses the long-standing question of why greens with non-iridescent structures are so rare.” It is difficult to make the color green by manipulating these tuneable spongy structure. A. Fairclough. Christopher J. Hill. Antonino Bianco. Richard A. L. Jones. Stephanie L. Burg. Andrew J. C. Dennison. Mary Snape. David M. Whittaker. Ashley J. Cadby. Sylvain Prost. Nature Scientific Reports 5, Article Number: 18317. December, 21, 2015. DOI: doi: 10.1038/srep18317. Video: Colourful birds. This video features several colorful birds. When you see them, consider how their colors are created – by tiny holes that scatter reflected light, not dyes and pigments.
Use the process of birds to make clothing and paint colors that don’t fade
