UV-curable encapsulation of surface—Modified organic pigments for inkjet printing of textiles

Aqueous dispersions of nano-scale organic pigments were prepared through ball milling and ultra-sonication in presence of dispersing agents. The well dispersed pigment was encapsulated into UV-curable resin via miniemulsion technique. Effects of molecular structure of organic pigments, type of dispersing agent and time of ball milling were investigated. Results showed that C.I. Pigment Green 7 had better dispersion stability with time compared with other pigments. Ultracentrifuge sedimentation test, shelf life stability, thermal gravimetric analysis (TGA) and transmission electron microscope (TEM) provided supporting evidences for the encapsulation of C.I. Pigment Green 7 into polyester tetra acrylate/1,6-hexandiol dimethacrylate. Zeta potential results proved that UV-curable encapsulation of C.I. Pigment Green 7 intensifies the charge on the surface of the pigment and significantly increases the dispersion stability. This method of modifying organic pigments to be used as pigmented UV-curable inkjet inks was found to be durable and effective in preliminary application in inkjet printing of textiles.