Preparation of waterborne nanoscale pigment dispersions for formulations of inkjet inks

Abstract

Textiles Inkjet printing as a new dyeing method with higher resolution, lower pollution and shorter run length has attracted more and more people's attention. Pigment inks have become one of the main colorant materials in this technology for its excellent light fastness and suitable to all sorts of textiles. However most of organic pigments with low polarity are hard to be wetted and dispersed in aqueous media, therefore the organic pigments should be modified before their application. In this paper, waterborne nanoscale pigment dispersion including Copper Phthalocyanine blue (P.B.15:3), Quinacridone red pigment (P.R.122), and Monoazo yellow pigment (P.Y.14) have been prepared by phase separation method and direct milling with dispersants method respectively. The properties (stability, particle size and apparent viscosity) of dispersion which prepared by different method were compared. The results show that the pigment dispersion has higher stability to alcohols, temperature and storage, and also lower viscosity; the phase separation method was more suitable to preparation of pigment dispersion for formulations of inkjet inks than direct milling with dispersants method; TEM photo indicated that the pigment particles were uniformly distributed in aqueous media and the XRD curves indicated that the pigment crystal was not changed after encapsulation by phase separation method.