Mordant-free Natural Dyeing of Cotton Fabric based on Metal Organic Framework (MOF)
This invention aims to develop a new mordant-free natural dyeing method for cotton fabric with the use of surface functionalisation of fabrics by Metal-Organic Framework (MOF). It enhances colour uptake of natural dye on fabric, promoting the use of natural dye.
Textile production a source of global clean water pollution from dyeing and finishing products. Synthetic dyes have been commonly used but its production and waste treatment processes have created environmental hazards. In particular, many nations have restricted the use of various azo-dyes. Meanwhile, natural dyes are sustainable and biodegradable but they have poor affinities with fibres and fabrics. Mordants can enhance dye uptake but the use of harmful heavy metal mordants leads to water pollution.
1. The project promotes the use of natural dyes in the textile industry. It can be applied in fibre, yarn, and fabric dyeing.
2. The surface functionalisation also works for polycotton and wool other than cotton.
1. This mordant-free dyeing method has higher dye uptake compared to conventional method with at least 50% better.
2. Dyed MOF-functionalised fabrics have good colourfastness of over 3.5, passing the standards of AATCC 61, AATCC 15, AATCC 107, and AATCC 8.
3. These fabrics have also high anti-bacterial efficacy against S. aureus and K. pneumoniae of over 99.99%, passing AATCC 100 standard. It has negligible skin irritation, passing ISO 10993.10-2010 standard.