Application And Quality Requirement Of Iron Oxide Pigment In Ceramic Industry
Iron oxide pigments due to wide, tasteless, non-toxic, inexpensive and other characteristics, in the ceramic industry has been widely used.
01 Application of iron oxide as raw material of green body:
The green body is the base material of ceramic porcelain
Iron oxide as a raw material coloring agent, mainly used in building ceramic wall tiles products. For example, imitation granite glazed porcelain tiles, the pigment preparation process:
Iron oxide pigments and a small amount of blank in the ball mill mixed into a paste, and then controlled by the quantitative pump into the mixer, in the mixer, a certain percentage of the paste and pulp mixed into high-speed slurry, the pigment and base pulp by a certain percentage Spray into the drying tower, to create a color powder.
Imitation granite glazed ceramic tile production process recipe:
Plastic raw materials 20 - 30%
Britain and other barren raw materials 20 - 40%
Feldspar flux 20 - 30%
Special pigment additives 1 - 5% (such as iron oxide, chromium oxide, etc.)
02 Iron oxide in ceramic glaze Application:
An enamel is a continuous vitreous layer attached to the ceramic surface
In the ordinary ceramic in the use of iron oxide coloring, the preparation of a variety of color glaze, iron ion price is different, iron oxide itself presents different colors. Such as: ferric oxide (Fe2O3) for the red powder, ferrous oxide (FeO) and iron oxide (Fe3O4) as a black powder. Can be used as needed, the choice of different iron oxide.
In addition to iron oxide itself is polychromatic, when in other glaze to add iron oxide, make the glaze more richer, glaze more beautiful. For example, in the alkali-containing boric acid glaze to add iron oxide, showing the red wine; in semi-matte and matte white glaze by adding iron oxide, showing bright brown, yellowish gray and camel to dark brown series of colors; Iron oxide with yellow glaze, just add a few percent of the iron oxide that can show a very strong yellow.
In addition, in the ceramic (glaze) manufacturing process, the use of different firing atmosphere, iron oxide color is also different, in the oxidation of the atmosphere, the iron oxide color change to yellow to reddish brown, and then change the grape red For brown. In the reduction atmosphere, it shows a blue to gray and dark changes, these changes in the glaze layer of Fe2 + and Fe3 + dynamic balance of the results of the transition.
03 Ceramic industry for synthetic iron oxide pigments
1, hue to stabilize the molecular size should be uniform.
2, Fe2O3 content is higher, less salt, the density should be relatively stable.
3, sand, iron and other mechanical impurities to the less the better.
4, color trends from dark to light color development color to bright.