Panjab University researchers develop tech to bleach fabric without chemicals

Continuing its efforts in research to achieve better results at developing environment-friendly technologies, Panjab University has come up with a unique method for textile industry, especially for fabric bleaching.

The breakthrough invention offers an alternative to the traditional denim bleaching process, known as stone washing. A patent, titled “A Process for Bleaching of Fabric Using Laccase” (Grant No. 552415), has been awarded to Panjab University. Prof Naveen Gupta, Prof Prince Sharma from Department of Microbiology and Prof Rajat Sandhir from the Department of Biochemistry, led the research, which was a part of Dr Sonica Sondhi’s Ph.D work.

Research scholars Sunena Jassal, Anupama Sharma, Dr Deepak Kumar, Dr Aditya Kumar and Rahul Wormoota have also been credited as inventors of the environment-friendly technology.

According to the researchers, textile manufacturing employs numerous processes to create fabric for various applications, with bleaching being the crucial step, which removes natural colour, impurities and other undesired characteristics to improve fabric quality.

For cotton, an oxidative bleaching agent such as dilute sodium hypochlorite or hydrogen peroxide is often used. However, these chemicals require substantial amount of water for processing, leading to pollution and environmental concerns.

The newly developed biobleaching process uses enzymes — isolated from an environment-friendly bacterium — that can bleach fabric without the use of chemicals. To improve cost efficiency, enzyme production has been optimised and unlike prior methods, the process does not require enzymatic mediators, making it economical for large-scale industrial use. Research is ongoing to allow multiple cycles of enzyme use, further enhancing cost efficiency.

The innovation represents a decade of dedicated research by PU’s Department of Microbiology, in collaboration with textile industry leaders in Ludhiana, who are also interested in technology transfer for this process. “This significant achievement underscores Panjab University’s commitment to addressing global challenges through research and innovation. Our researchers and teachers are always striving for better processes for environment,” Prof Rajat Sandhir said.