Research on micro mechanism of water-based disperse ink and optimization of driving waveform for inkjet ink

Abstract

In this paper, we use density functional theory (DFT) to optimize and calculate the geometries and vibration frequencies of H2O, EG (ethylene glycol) or H2O/EG in the ink (B3LYP/6-311++G** basis set, self-consistent reaction field theory (SCRF) and PCM polarization unified field model). LF-NMR (low-filed nuclear magnetic resonance) further confirmed the weak interaction between H2O, EG or H2O/EG molecules, which had a decisive influence on the viscosity and mobility of ink. According to the analysis of the peak of the inversion spectrum (T22) of the ink, the viscosity of the ink increases with the left shift of the relaxation time. The inkjet performance of the ink is closely related to the physicochemical properties of the ink and the driving waveform of the piezoelectric nozzle. Exploration of the sharpness of the inkjet printing pattern that the microstructure and weak intermolecular interaction of the ink bounds the mobility of the solvent in the ink, which increases the viscosity of the ink (3.28-5.11 mPa.s), and the ink overcomes the capillary effect of the fabric, which makes the diffusion of the ink in the fabric decrease (7.23-3.91 %).