Cobalt blue hybrid pigment doped with magnesium derived from sepiolite

Abstract Owing to the scarcity in nature of cobalt ores and the disadvantages of cobalt blue prepared via traditional solid-phase method, the high cost of cobalt blue pigment severely restricted their wide application in the relevant fields. Here, sepiolite was employed to fabricate the bright blue cobalt blue hybrid pigment via combining chemical co-precipitation and calcination process. The introduction of sepiolite not only dramatically decreased the cost of cobalt blue pigment, but also enhanced its color property presumably due to the doping of magnesium derived from sepiolite. The hybrid pigment calcined at 1100 °C for 2 h exhibited good color properties (L⁎ = 55.8, a⁎ = −2.3, b⁎ = −55.0), excellent thermal stability and suspension stability. The as-prepared hybrid pigments as a coloring pigment could effectively improve the heat-resistant performance after being incorporated into organosilica coating. In addition, the hybrid pigments could be well sprayed onto various substrates via a facile procedure. Thus it is expected to apply this low-cost bright blue cobalt blue hybrid pigments into various fields.