British scientists have devised a way to use electromagnetic radiation to identify counterfeit textiles, a discovery that could help recover billions of dollars in lost revenue for the fashion industry each year.
World-famous and highly competitive, the British fashion industry is worth £21 billion ($32.5 billion) to the UK economy, and as much as £37 billion when wider contributions, including tourism and related businesses, are taken into account. However, the production and sale of counterfeit textile goods is on the rise and is believed to cost the British fashion industry as much as £3.5 billion ($5.4 billion) each year—and, as counterfeiting technology improves, fake goods are becoming harder to spot.
Now, a new method from researchers at the National Physical Laboratory (NPL), U.K. uses terahertz time-domain spectroscopy to identify counterfeit textile goods. The technique involves placing a sample of fabric within a beam of terahertz radiation and analyzing the properties of the terahertz waves after they pass through the fabric. The composition and structure of different types of fabric give rise to different rates of beam scattering and absorption, says the team, essentially assigning each type of fabric with a distinct transmission profile, or signature. The detection of this unique signature could indicate whether the fabric in question is counterfeit.
During experimentation, the technique was able to clearly distinguish between fabrics that looked and felt similar but that had different compositions—including plain wool and the more expensive merino wool, and natural and synthetic silk. The results are published in the journal Applied Optics.
“Counterfeit clothes can look and feel almost exactly like the real thing, so customs officials need technological assistance to spot them,” John Molloy, who worked on the project at NPL, said. “Terahertz spectroscopy is a fast, safe and reliable test that could help safeguard one of the UK’s most valuable industries.”
The next stage in the research project will be to test batches of the same type of fabric from the same manufacturer, and to create a database of the terahertz transmission properties of many different fabrics. The researchers also hope to further study the relationship between the terahertz transmission properties and the properties of the fabrics themselves.
