PB28 Cobalt Blue pigment can be produced using different synthesis routes, primarily solid-state reactions and liquid-phase processes. The selected process directly affects particle size distribution, agglomeration behavior, color consistency, and suitability for downstream applications such as plastics, coatings, and ceramic inks.
In solid-state processes, cobalt and aluminum oxide precursors are mixed and calcined at high temperatures to form the cobalt aluminate spinel structure. This route is widely used in traditional pigment manufacturing due to its robustness and scalability.
However, solid-state synthesis often results in relatively larger primary particles and strong agglomeration. Post-milling is typically required to reduce particle size, which may introduce broad particle size distributions and batch-to-batch variability.
Liquid-phase or controlled precursor processes involve reacting cobalt and aluminum sources in solution before calcination. This approach improves precursor homogeneity and enables more uniform spinel formation during firing.
Compared with solid-state routes, liquid-phase processes generally produce PB28 pigments with finer particle size distributions and reduced hard agglomeration. These characteristics improve dispersion stability and color consistency.
The synthesis route has a direct influence on pigment dispersibility. Solid-state PB28 often requires higher dispersing energy to achieve acceptable dispersion in polymers or inks.
Liquid-phase derived PB28 typically shows improved dispersion behavior, lower sedimentation tendency, and more predictable rheology in coating and ink systems.
Process uniformity affects color reproducibility. Liquid-phase routes allow tighter control of stoichiometry and crystal growth, resulting in lower batch-to-batch color variation (ΔE).
In contrast, solid-state processes may exhibit higher ΔE variability due to inhomogeneous precursor mixing or uneven calcination.
For ceramic ink and other fine-dispersion systems, reduced agglomeration and controlled particle size are critical to prevent nozzle clogging and ensure stable printing performance.
PB28 pigments produced via controlled liquid-phase routes are therefore preferred for applications requiring dispersion stability and process reliability.
Solid-State Process: robust and scalable, but prone to stronger agglomeration and broader particle size distribution.
Liquid-Phase Process: improved particle uniformity, better dispersion behavior, and lower color variability.
Application Fit: liquid-phase PB28 is better suited for ceramic inks and high-end coatings.