Rope dyeing of fabric in supercritical carbon dioxide for commerical purposes

A novel method for fabric rope dyeing in supercritical carbon dioxide fluid has been successfully developed for the first time for commercial purposes by employing a custom-built machine. The influence of parameters such as system pressure, temperature, and dyeing time on fabric colour strength was investigated, and the parameters optimised. Moreover, the level dyeing property, reproducibility, and colour fastness were investigated and evaluated under various conditions. The carbon dioxide recycling efficiency and the running costs of the proposed process in comparison with conventional processes for commercial production purposes were also investigated. The rope dyeing results show significant influence of the process parameters on fabric colour strength. Satisfactory and commercially acceptable products with a good level dyeing property, high reproducibility of coloration, and good fastness, rated at 4-5 or 5 for washing and rubbing, were obtained with supercritical carbon dioxide fluid. Moreover, a carbon dioxide recycling efficiency ranging from 92 to 95.2% was possible. In comparison with conventional dyeing processes, running costs were lowered by employing the proposed process and rope dyeing machine.