Clean dyeing of cotton fabrics by cationic colored nanospheres

Dye/polymer nanospheres, a new type of colorant, are applied in various applications in printing inks, coatings, textiles and other fields by virtue of its excellent color properties. In this research, we adopted a novel composite dye nanospheres modified with polyethyleneimine, which was further applied to the environmentally friendly dyeing of cotton fabrics. After modification, the cationic polyethyleneimine composite dye nanospheres (PDNP) have homogeneous particle size, better monodispersity and stability in aqueous solution. In addition, the hydrated particle size increased by 10 nm and the zeta potential changed from −30.4 to 40.7 mV after polyethyleneimine modification. Meanwhile, the color depth of cotton fabrics dyed with different colors of PDNPs is 3–5 times of the corresponding dye colored samples. The color fastness and durability of the PDNPs dyed cotton fibers are satisfied for practical applications. The colored PDNPs can directly dye untreated cotton fabrics without adding salt and alkali, implying a simple dyeing process and pollution reduction.