Relaxation Shrinkage Treatment for Knitwear

09 Relaxation shrinkage treatment for knitwear using low temperature rapid evaporation
This project aims to utilize the low temperature rapid evaporation technology developed from the completed parent project ITP/009/08TP for building an industrial scalable machine. This machine will become a demonstration unit for introduction of the new relaxation finishing process on sweaters to the industry. The new process with advantages of high energy efficiency and cost effectiveness can replace the conventional washing and tumble drying process.

The new relaxation process is suitable for open width knitted fabric. With appropriate mountings, knitted sweaters can be processed.

Industry Benefit

The process is potentially beneficial to sweater production. A WTD process usually comes before the final pressing in the sweater production line to correct dimensions and improve hand properties. Comparing to WTD, it is estimated that the new LPR process uses 19 times less electricity and 40 times less water as well as achieving 120 times faster on processing. Besides, the LPR offers a cleaner fabric appearance, higher pilling test grade and brighter colours especially for darker shades such as black and navy blue.

Technological Breakthrough

The WTD process relaxes knitted fabric by mechanical agitation while the LPR one relaxes knitted fabric by micro-agitation originated from expansion of water during phase change. The latter can better preserve the fabric properties.

Project Name (ITF)
Trial: Novel Finishing Treatment for Knitwear Using Low Temperature Rapid Evaporation (ITT/040/14TP)
Project Number (ITF)