Contact: Prof. Jeremy Baumberg, NanoPhotonics Centre, Dept. of Physics
Mentor: Dr. Julian White

Nanostructured materials can give a brilliantly coloured appearance without any need for dyes or pigments. These ‘structural colour’ materials are inspired by the iridescence of butterfly wings and peacock feathers, which derive their colour from the interaction of light with their periodic nano-scale structure.

Most materials used in manufacturing are coloured using pigments or dyes.These can be toxic, prone to bleaching by UV, or subject to other surface-level degradation. The use of structural colour means that the material is the colour – so no colour transfer or loss can occur, and the materials are benign to the environment. What is more, since the colouration is tied to structural parameters, the material’s colour can be changed by manipulating its nanostructure.

This research, begun over 10 years ago, has led to the production of elastomeric films with iridescent colouration that can be tuned by bending and stretching. In a new direction, the team are now investigating thin coatings based on polymer-metal composites, in which the colour can be controlled electrically.

Fabric, films, injection moulded items or any other solid surface could be coated using these pigment-free colour-changing materials. The techniques rely on scalable manufacturing processes, at relatively low cost, and could be applied to a wide range of applications requiring thin coatings with switchable colour.

The technology is protected by a granted US patent and is undergoing examination in Europe.

The challenge for the i-Team is to investigate different markets which may benefit from very thin tuneable colour coatings, through talking to industry experts and gathering feedback and ideas. They will then analyse the feedback from these industries, and recommend the best commercial direction for the researchers going forward.

Baumberg

Structural colour in thin nano-patterned polymer films and polymer-metal  composites