Ink-Jet Printing of Colored Latex Inks with a “Soft” Core–“Hard” Shell Structure

Abstract

Colored latex particles (CLPs) as a novel colorant have been widely applied to salt-free dyeing and printing due to their adjustable composition, brilliant colors, excellent durability, and small particle size. In this paper, the effects of glass-transition temperatures (T g) on the filterability of CLP inks were first studied, and the results showed that the CLP inks can be successfully filtered and ejected when the T g’s of CLP inks exceeded 48 °C. Based on our previous research, CLP (T g = 25 °C)-printed fabrics had excellent color fastness and a soft hand feel, while a stiff hand feel occurred with the increase of the T g. Herein, the CLPs with a core–shell structure (CLP@PS) were designed using CLPs (T g = 25 °C) as a “soft” core for ensuring the color fastness of printed fabrics and PS as a “hard” core for ensuring excellent filterability of inks. Transmission electron microscopy and dynamic light scattering indicated that the prepared particles had an obvious core–shell structure, and the particle size was 96 nm. To balance the filterability of inks and color fastness of printed fabrics, the encapsulated thickness was optimized at 20 nm by adjusting the amounts of styrene (St) and 2,2′-azobis­(2-methylpropionamidine) dihydrochloride (AIBA). The flow rate and filtration time of CLP@PS inks were 8.9 mL/s, and 11 s, respectively. Finally, the CLP@PS inks were applied to ink-jet printing of cotton fabric. Compared with pigment ink-jet printing, CLP@PS-printed fabrics had a softer hand feel and better rubbing and washing fastness.