Thermoresistant pigments interaction with molten  glazes often restricts the use of some pigments in obtaining the desired glaze nuances.

 Major difficulties arise when the nuance of the glaze colored with the dispersed pigment in the vitreous matrix is different from the ionic color generated by the pigment dissolution. As a common situation, CaSnSiO5 pink malayaite pigments with chromium as chromophore often undergo a color change from pink to green after structure deterioration by the molten glaze and inclusion of the chrompohore in the glass matrix, as Cr3+.

The obtained results show that in the case of tableware faience glazes, annealed at temperatures between 11501190C, the glaze aggressiveness can be controlled within certain limits by taking action on the chemical composition, and adding wollastonite, quartz or ZnO during the milling process.


 

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