Among the pigments for ceramic glazes, the brown series of pigments occupy a large market. Especially in the production of tiles and retro tiles, two series of golden yellow and red brown are widely used.
The brown series mainly have two crystal structures of Fe-Cr-Zn-Al and Fe-Cr-Zn, and the red iron oxide pigment is mainly added in the form of colorant. The trivalent iron ion maintains the red color and is colored by compounding with chrome green, resulting in shades ranging from golden yellow to dark brown. In this study, the following experiments were carried out: a frit with chemical composition was used, and 3 percent of the colorant was added to the frit. The hair color changes from golden yellow to reddish-brown, and the lightness value of the colorant also decreases accordingly; at the same time, the experiment found that the glaze pinholes also increased accordingly.
