Environmental substitution for PbCrO4 pigment with inorganic-organic hybrid pigment

- Hybrid pigments with SiO2, TiO2 and sepiolite as main component were prepared.
- Color performance of hybrid pigments were tested and compared with PbCrO4.
- Heat resistance and photo-stability of hybrid pigment are compared with PbCrO4.
- Replacement possibility of PbCrO4 by hybrid pigment was evaluated.

A series of inorganic-organic hybrid pigments, with a main component of inorganic materials (SiO2, TiO2 and sepiolite), were fabricated and utilized as an environmental substitution for PbCrO4 pigment. The structure between inorganic materials and organic pigment were determined by transmission electron microscope (TEM), zeta potential test and surface area analysis, and the color performance of prepared hybrid pigments were tested and compared with PbCrO4. The analysis results showed that the SiO2 was encapsulated by organic pigment to form a core-shell structure, and then the SiO2@organic pigment hybrid combined with TiO2 (or sepiolite) through electrostatic attraction. When the mass ratio of SiO2:TO2:organic pigment and coupling component AAMX:IRG was 24:8:8 and 3:2 respectively, the prepared hybrid pigment showed a similar color performance with PbCrO4, and the heat resistance and photo stability test results showed that the prepared hybrid pigment could be a potential substitution for PbCrO4 in water ink. Additionally, the heat resistance of prepared hybrid pigment was adjusted by addition of sepiolite, and when the mass ratio of SiO2:TO2:sepiolite:organic pigment was 16:8:20:8, the new fabricated could be utilized as a substitution for PbCrO4 in polypropylene plastic.