Uster has developed a new data-based system to assess mechanically recycled cotton fibres and determine their suitability for different spinning processes and end uses. The Uster Recycled Fiber Matrix addresses the challenge of the large variation in fibre quality caused by differences in waste streams, recycling methods and source materials.

Instead of assessing recycled cotton through a single measurement, the matrix combines two fibre properties to provide a more detailed indication of how the material is likely to behave during processing and how it may affect yarn quality.

The system focuses on physical fibre properties that directly affect spinning performance. These include mean fibre length, the length of the longest 5% of fibres and short fibre content. Beyond fibre classification, Uster sees the matrix as a practical tool for bale management, blending and adjusting spinning parameters.

Separating recycled cotton bales based on fibre length, source and colour can help mills reduce variation in their raw materials and maintain more consistent processing conditions.

The company said the aim is to provide recyclers, spinning mills and brands with a common, data-based framework for evaluating recycled cotton and making better decisions about its suitability for different textile applications.