A bit of imagination and strong contact with the business community have helped an idea about polishing injection moulds develop into a product with broad perspectives for health and climate applications.
Even though a steel surface may appear smooth and even to the naked eye, it will usually feature tiny irregularities where bacteria and limescale can take a firm hold—and have a negative impact on energy bills. You cannot polish the problem away, but a coating can be used to cover up the irregularities.
In his PhD project, Henrik Pranov came up with a method for creating a coating that was not only ultra-thin, but also extremely smooth and corrosion-resistant. By transforming silicone oxide molecules into a fixed network structure, Henrik succeeded in reducing roughness to just a few nanometres.
“We originally developed the idea for use in polishing injection moulds, but then thought it might be suitable for many other areas. The most obvious application was in heat exchangers because our coating is so thin that it doesn’t have a significant effect on heat transfer,” relates Henrik Pranov, who used his patent to found the company Inmold—specializing in surface treatment—in 2007.
But there proved to be many more opportunities in his patent. So the company SiOx came into being in 2013 and is currently taking shape under the guidance of two DTU researchers, Annemette Hindhede Jensen (who has a PhD from DTU Energy) and Alexander Bruun Christiansen (who has a PhD from DTU Nanotech). The company is currently working with Alfa Laval, which manufactures heat exchangers, on a project centred on the development of SiOx coating, with financial support from Innovation Fund Denmark.
“Silicone oxide—also known as silica—is distinguished not only by its own properties as a coating material, but also by being both simple and pure. It is readily found in nature and is even used as a dietary supplement. That is why it can also used in connection with foods—in the pasteurization of milk, for example, where bacteria tend to latch onto the vats and vast amounts of water are required to rinse them clean,” relates Annemette.
In the long term, Annemette envisages the SiOx coating being used on frying pans and other kitchen utensils. There are all kinds of exciting perspectives to the levelling technology.