Q & A: Robert Rix of Gorix Ltd.
Interest in Medical Uses of Electroconductive Carbonized-Fibre Material Heats Up
Robert Rix is the inventor of Gorix, a highly conductive "smart" material that is able to regulate its own temperature without a thermostat. Rix, who with codirector John Gordo founded the company in Rotherham, S Yorks, UK, which is named after them, presented his invention at the recent Medical Design & Manufacturing West Exposition and Conference in Anaheim, CA, USA. We took the opportunity to find out more about this "miracle material."
Q: I understand that it all began with a horse?
A: I had a specific challenge, which was to develop a type of blanket for heating horses. The existing technology—a nickel-chromium-wire heating element—experienced breakages and would stop functioning. So I set about to develop a sheet heater that could be built into these blankets. It was really a process of elimination: I was looking for a fibre that functioned in a certain way. Having found that fibre, the rest was simply evolution.
Q: How is the fibre produced?
A: It's a polymer-based material that we carbonize in a very specific way. The material is carbonized in its woven state, which makes it distinct from carbon-fibre materials that are carbonized before they're woven. Gorix is a carbon textile rather than a woven carbon fibre, and the rigorously controlled weaving and spinning regime is where most of the magic is contained.
Gorix is baked at 1000°C, so that almost all the elements other than carbon are burned away. This involves a highly complex method to ensure that the material does not fall apart during the process.
Q: What are some of the material's characteristics?
A: Infinite flexibility, breathability, uniformity of heat, and linear change in resistance subject to temperature. Linearity around body temperature, in particular, makes it an ideal material for medical applications. We can harness that change in resistance for the purpose of making not only heating elements but also temperature sensors. The heating element and temperature sensor can be laminated together to produce a self-controlled heating element. With some simple circuitry, it is possible to create a combined heating and temperature control system that is efficient and extremely accurate and stable in operation, and that has virtually no hysteresis.
Q: What are some of the more promising medical applications for Gorix?
A: It is especially well suited for applications where temperature management is critical—infant incubators are a good example—or where precise control is needed.
The material could be used to produce a low-voltage heated mattress for geriatrics, for instance. It could be encapsulated to make it waterproof and could run with a 12- or 24-V power source. The temperature deviation factor is ±1°C. And because there are no wire elements, the problem of hot and cold spots is eliminated.
It is also worth noting that the material is x-ray opaque. If a company is looking at creating a heating element for an operating table or an alpine recovery stretcher, for example, one other advantage of using Gorix is that x-rays can be taken with the garment in place.
Q: What lies ahead for Gorix the company?
A: Our expertise is in producing the concepts and taking them through to the prototype stage. We then try to attract the interest of manufacturers. I can't see many applications where the material would be used in its raw state; it will almost always be combined with another material or product.
We have subcontractors in the UK who have carried out the converting, and we recently formed an alliance with Modernistic (St. Paul, MN, USA), which will act as our US-based converter. We haven't found anyone in mainland Europe yet, but that is one of our primary goals.
For more information, contact Robert Rix, Gorix Ltd., 14 Dovedale Rd., Rotherham, S Yorks S65 3AJ, UK; phone and fax: +44 1709 370529.
