The industry has long relied on the use of high refractive index media, such as titanium dioxide (TiO2) nanoparticles and other inorganic materials, to produce so-called light scattering enhancers. Such materials are processed in the production of white coatings and to improve performances of colour pigments in a large variety of industries: from paint to cosmetic and even for food colouration. However, they have recently been found to be cancerogenic and dangerous to humans. Further, their mass production combined with their property of non-degradation is a threat to our environment with unforeseen consequences.
The aim of our project was to produce a novel biocompatible material – cellulose-based scattering enhancers- to mitigate environmental pollution and health issues of current titanium dioxide whiteners. We wanted to show how we are able to select by chemical processes bio-sourced cellulose colloidal particles with optimised optical properties to be used as sustainable white enhancers. In order to reach this goal we took inspiration from nature, where random networks made of biopolymers with low refractive index are capable of achieving a very strong scattering of the visible light using a clever combination of size and morphology. Our cellulose based fibrillar nanomaterials have confirmed to be ideal to mimic naturally optimized scattering systems due to their inherent rod-like morphology, availability and excellent mechanical performance.
We are very pleased to confirm that all our planned objectives have been successfully reached and that the project has successfully concluded with the launch of the spin-off company Impossible Materials Ltd (www.impossiblematerials.com) which is currently licencing and soon commercialising our cellulose-based scattering enhancers as a safe and sustainable alternative to titania nanoparticles. The company is already having a positive economic impact with four full-time employees working actively on the start-up and for society by raising awareness of this problem and developing more healthy and safe products.
We are very confident that such cellulose-based photonic whiteners could replace traditional materials such as TiO2 in many products: from cosmetics, to pharmaceuticals, to paints. As cellulose is derived from natural, edible fibres, cellulose-based scattering enhancers can also meet food safety standards and hence be used as a colourant additive in food and beverage industry.
