Synthesis of core–shell-type styrene acrylic latexes with low NMA content and their application in pigment printing pastes

In this paper, novel core–shell polymers comprising styrene (St) and butyl acrylate (BA) in both core and shell layers of the polymer particles have been synthesized and employed in pigment printing pastes which were applied on 100% cotton and 65% cotton/35% polyester (PET) fabrics. The aim was to reduce the NMA content and the formation of free formaldehyde from pigment printing pastes by employing newly synthesized core-/shell-type polymers. After five washing cycles, the synthesized core-/shell-type polymer including 1% NMA in the core and 1% NMA in the shell with T_g values +30°C and −20°C, respectively, with lowest total NMA content (1.03%) yielded the best result and showed closest ΔE values to the commercially available polymer including 4% NMA. Dry and wet rubbing fastness results showed no significant changes in the absence of NMA when compared with NMA containing samples. The penetration degree of the pigment pastes of the corresponding polymers was relatively higher on 100% cotton fabric for both red- and blue-colored pigments. A negligible decrease in color strength has been observed for all polymers when colored in red.