Abstract: In order to obtain self-dispersal nano carbon black pigment. Carbon black surfaces were modified by nitric acid oxidation.The surfaces group structure, surfaces oxygen content of the original and oxidized carbon black were investigated by means of FT-IR, XPS, Element analysis instrument, respectively. The oxidized carbon black and distilled water were mixed according to 30% solid content, after which the mixture was ground for 45 min by small-grinding mill equipment, and self-dispersal nano carbon black pigment would be prepared successfully. The particle size distribution and the dispersal stability of the pigment were investigated by means of particle-size analyzer, spectrometer, respectively. The results showed that some highly marked hydrophilic character functional groups on carbon black surfaces, including C=O, O-C=O, O-H, were increased greatly by nitric acid oxidation and the oxygen content of oxidized carbon black was incresed nearly 6 times comparing original carbon black. The particle size distribution of self-dispersal nano carbon black pigment was within 200 nm and nano carbon black pigement was homogeneous and stable.

Key words: carbon black pigment%ntirc acid oxidation%self-dispersal