Natural polymer for controlled ink droplet spreading
Digital inkjet printing is a crucial cleaner technology in cotton fabric coloration, but the problem still remains that current cotton surface treatment is inefficient in controlling the spreading of micro-scale ink droplets causing poor image quality and low dye utilization efficiency. In response to this problem, a kind of natural polymer named propylene glycol alginate (PGA) was adopted in cotton surface treatment to gain efficiency and environmental friendliness for cotton inkjet printing. Results show that PGA formed uniform film on fiber surface and in the gaps of fibers, inhibiting the fiber capillary effect. Due to the strong hydration ability of PGA, the ink droplets could be quickly held, preventing the ink spreading. Due to the numerous hydrophobic side groups on PGA molecular structure, the ink penetration was effectively decreased by the PGA film formed on cotton surface, maintaining most dyes on fabric surface with increased color strength.
High-quality inkjet printing image on cotton fabrics
In comparison to polymer-free treated and sodium alginate treated samples, the apparent color depth (K/S value) increased about 1.0–1.7 times for different inks. Moreover, the electrostatic repulsion between reactive dyes and cotton fibers was weakened by the less electronegative PGA film, realising enhanced dye fixation and desired fastness. According to the reseachers, their work provides an efficiency method to obtain high-quality inkjet printing image on cotton fabrics and shows great potential in promoting the development of textile inkjet printing.
The study has been published in Progress in Organic Coatings, Volume 172, November 2022.