Colour in the sun

Wool clothes that change colour in the sun and provide protection from harmful UV rays could be the next fashion trend thanks to new research at Deakin University.

Tong Cheng, a PhD student with Deakin’s Centre for Material and Fibre Innovation, has developed a way of colouring wool with photochromic dye.

Photochromic products undergo a colour change when exposed to UV radiation. The problem is that photochromic dyes and wool are incompatible when applied by traditional dyeing methods.

But now, Cheng has created a polymer that can hold the photochromic dye and be applied to the surface of wool fibres. The special polymer contains a huge number of tiny pores that trap the dye.

Cheng had to ensure that the pores in the polymer were just the right size - if they were too large, for example, the dye would seep out. It was also important that the polymer allowed the colour change for the dye to take place quickly.