Coded yarn could make textiles traceable

A yarn-based coding system that can be used to track textiles through the supply chain has been developed by researchers.

The yarns function as an “optical stamp” on the surface of woven or knitted fabric that is introduced during the weaving process and unlike other technologies such as RFID tags or barcodes is an intrinsic part of the textile product and cannot be removed. The yarns are coded using twist-based optical features which can be generated on a hollow spindle frame, and can be designed so that each ne is unique.

“Barcodes and RFIDs possess low security again copying and reproduction, which means an identical tag can be easily reproduced and placed with a counterfeit product, write the researchers in the Journal of Manufacturing Systems.

Furthermore, these tags are generally removed at the point of sale, so it becomes difficult to track the history of a product back thereafter, they point out, while embedded foreign materials such as tracking chips can raise privacy issues and cause problems with recycling.

The team, led by Vijay Kumar of the University of Borås in Sweden, have previously described the development of the coded yarn and in the latest paper take the concept further as a textile-integrated tag, putting it through its paces in real-world settings, such as harsh washing treatments, as well as using a decoding algorithm to extract information encoded within the tags.

Right now, washing and other factors mean that the reading reliability of the tags doesn’t stack up to barcodes, but the researchers believe that with refinement – such as the use of fixed identification marks to direct reading and decoding – it has the potential to become an effective traceability technology.

“Since the reproduction of these tags is not easy like other tags, including barcodes and RFIDs, they can provide enhanced security to textile products from counterfeits,” conclude the researchers. “Further, from the economic aspect, yarn-based tags are normal textile, therefore, there is no need of special material components and in-house production in a textile industry can be done.”