Researchers from Colorado State University (CSU) have discovered a way of making bamboo fabric that is resistant to the sun’s damaging ultraviolet (UV) radiation and has anti-bacterial properties.
Widely available in Japan, China, India and other countries, bamboo fabric is soft, durable and elastic. It hangs as gracefully as silk, and has an attractive, lustrous sheen. A leading option in the so-called ‘ethically produced’ clothing market, bamboo is one of the world’s fastest growing plants, reaching maturity in about three to four years.
‘Bamboo is environmentally friendly,’ said CSU’s Subhash Appidi. ‘Pesticides and other agents are necessary to grow most other natural fibres – there is nothing like that in bamboo production.’
But despite bamboo’s promise as an environmentally friendly fibre, Appidi said untreated bamboo fabric has plenty of room for improvement. Raw bamboo fabric lets almost all damaging UV radiation pass through and reach the skin. And while many tout bamboo’s inherent anti-bacterial properties, Appidi found that untreated bamboo fabric did not live up to antimicrobial expectations.
‘All cellulose fibres allow more moisture to leak in and provide more food for bacteria to eat. That’s why bacteria grow more on natural fibres rather than synthetic fibres,’ he said. The resulting bacterial blooms can lead to unpleasant odours and unsanitary clothing.
Appidi’s goal is to create clothes for use in the medical environment that are nearly 100 per cent antibacterial and UV-resistant. Appidi increased the UV-protecting abilities of fabric by colouring pieces of commercially-available bamboo cloth in a dye laced with UV absorbing chemicals. After finding the optimal concentration of absorbing chemicals, he tested UV protection levels.
To improve on the intrinsic antibacterial properties of bamboo, Appidi treated pieces of commercially purchased bamboo fabric with Tinosan – one of the better antibacterial agents on the market right now, according to the researcher.
His results showed a 75-80 per cent bacterial reduction, a significant improvement over untreated bamboo fabric. There was also a profound increase in UV protection, he said. In terms of ‘ultraviolet protection factor’ (UPF), any value of over 50 is deemed safe against UV rays. Appidi said his treated fabric almost reached 56.
More research may get Appidi’s bamboo fabric in hospitals – and eventually shop shelves. He is investigating other antibacterial agents that may help him attain a 99 per cent bacterial reduction in bamboo fabric. Insight into the effect of multiple laundry cycles is also necessary, though preliminary findings suggest that the UV and microbial protection remain after washing.
Eventually, Appidi would like to see bamboo fabric become as common in the US as it is in Asian countries.