Using low concentration polyethylene glycol to regulate the microstructure of ink to improve the printing quality of cotton fabric

Abstract

Satellite droplets, excessive ink spreading and penetration present significant obstacles to the advancement of inkjet printing on cotton fabrics. Traditional ink preparation methods utilizing organic solvents are unable to effectively address these issues. This study addressed these challenges by investigating polyethylene glycol (PEG) as a component in reactive dye ink. It was found that the PEG with longer molecular chain formed more complex coil after dissolution, which could increase ink viscosity and inhibit satellite droplets more effective. Meanwhile, the reduction of PEG concentration promoted the swelling of ink to sodium alginate (SA) film. High swelling degree and complex PEG coil could limit the ink spreading and penetration. Solid state PEG further restricted the ink spreading and penetration during the dye fixation process. Ink prepared by 3.2 wt% PEG20000 achieved no satellite droplets, the smallest spreading area and lowest permeability, and the highest dye fixation rate. Compared to commercial (CI) ink, it was evident that PEG20000/Red 218 ink exhibited less spreading and penetration, and had a higher dye fixation rate. This study introduces a promising approach for the production of high-quality, cost-effective reactive dye inks using the coil structure of polymer after dissolution.