Ceramic pigments are a general term for pigments used on ceramics, including pigments for glaze, underglaze, glaze and body coloring. In the process of ceramic production, these pigments are calcined at different temperatures, and the requirements for pigments with different uses are also different.
Technical requirements for ceramic pigments:
(1) The color of the powder is basically the same as that of the standard sample. The moisture content of the powder should not exceed 0.4%.
(2) The pH of the powder is not greater than 8.0 for lithographic pigments; not greater than 9.0 for screen printing pigments.
(3) Particle size For lithographic pigments, the particles with a diameter of less than 15um should not be less than 95%, and the largest particle should be less than 30um;
For screen printing pigments and pigments in glaze, the particles with a diameter of less than 15μum should not be less than 90%, and the largest particle should be less than 30um; for pastel pigments, the largest particle diameter should be less than 840um;
For underglaze pigments, the particles with a diameter of less than 15μm should not be less than 92%, and the largest particle should be less than 30um;
Among them, the manganese red particles with a diameter of less than 15 μm should not be less than 82%, and the largest particle should be less than 35 μm.
(4) The tone and color of the ceramic pigment should be basically consistent with the standard sample.
(5) The amount of lead and cadmium dissolved in the glaze and in the glaze should meet the requirements.