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

Abstract Satellite droplets, excessive ink spread 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 the polyethylene glycol (PEG) as a component in reactive dye ink. It was found that the longer the molecular chain of PEG, the more complex coil formed 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 ink spread and penetration. Solid state PEG further restricted ink spread 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 ink, PEG20000/Red 218 ink demonstrated smaller spreading area and lower permeability, and higher dye fixation rate. This study introduces a promising approach for the production of high-quality, cost-effective reactive dye inks using polymer coil structure.