Enhancing inkjet image quality through controlling the interaction of complex dye and diol molecules

Abstract

Digital inkjet printing has been widely used in the textile industry due to the advantages of low cost, high efficiency, flexible processing and so on. Although a number of methods have been reported on inkjet printing of high-quality images on fabrics, challenges still remain in preparing homogeneous inks and printing high resolution images. Herein, we describe a simple method to prepare stable inks for high performance digital inkjet printing on cotton fabrics. Two ecofriendly organic solvents of ethylene glycol and diethylene glycol were applied in the Reactive Black 8 in. solutions, respectively. By adjusting the interaction between dye and diol molecules, the resulted Reactive Black 8 inks showed an increased viscosity and decreased surface tension, which facilitated the formation of complete and stable inkjet droplets during the printing process. Moreover, introducing these solvents into the dye solution can effectively disaggregate the clusters of Reactive Black 8. When 5 mol/L diethylene glycol or ethylene glycol was used in the Reactive Black 8 solution, complete and stable ink drops can be formed, and the diffusion area of the ink drops on fabric was obviously reduced, thus clear and high-resolution patterns can be produced on the cotton fabrics. We characterized the chemical and physical properties of the inks and evaluated their printing performances on cotton fabrics. The mechanism of interaction between dye molecules and organic solvents was also investigated. Results from this work may promote the wide development of inkjet printing techniques and extend its application in high performance textiles.