According to the general firing temperature, firing atmosphere and base glaze composition conditions, from the characteristics of experience data or grasp of the existing color to choose colors. When the need to obtain intermediate color, the relative contents of several pigments to adjust the available physical complementary method. Such as iron oxide, zirconium vanadium zirconium blue, yellow and other colors, color adjustment, is a good example to adjust hue Applied Physics complementary method. When the glaze is opaque, we should choose suitable opacifying agent, selection of opacifying agent not only to pay attention to its opacifying effect, must pay attention to the color effect on pigment.
Amount of pigment
The pigment amount depends on the color itself in glaze and glaze color depth required. In general, adding amount of pigments in the glaze is about 4 ~ 10%. Some hair color pigment strong ability (such as cobalt blue pigment) and its adding amount can be below 4%; and some hair color ability weak pigment (such as Ge Xihong), the amount of over 10%.
Glaze slurry preparation
In the Ceramic Pigment grinding before, should first control pigment fineness, at present, the pigment fineness of product provided by the suppliers are generally in the 250 mesh sieve range more than 0.05% or so. Pigment fineness greatly on its influence in the glaze color, usually pigment granularity more details in the glaze color ability is strong; and vice versa, and lead glazed coarse and lose luster; but some in the glaze color is not higher solubility, ball milling is careful, otherwise, will reduce its in the glaze color hair ability. Processing fineness color glaze generally million pore sieve (250 mesh sieve residue of about 0.1%).
The glaze
Because pigment easy layered bottom, so in glaze, glaze, glaze slurry uniformity is very important, if the control is undeserved, may cause the product color. The glaze, color glaze layer thickness should be thick, so as to enhance the glaze color saturation, and also has the advantage to overcome the influence of billet color glaze; in addition, the uniform control of glaze thickness, is also an important means to control the products have color defect.
Firing
glaze firing must strictly control the firing temperature and atmosphere according to the species characteristics and glaze color. Therefore, large firing chamber furnace is detrimental to the firing glaze color, because the temperature and atmosphere which cannot be obtained at various sites uniform.
Influence of process factors showed pigment in the glaze color
Effects of A, glaze preparation process
(1) effects of milling equipment: the main effect of ball mill liner and ball stone material. If the lining material for natural flint, balls to natural stone, it is easy to wear, the impurities mixed in glaze and glazed colors; if using high alumina ball mill lining and balls, because of its good wear resistance, little impurity wear into the glaze; even a small amount of wear particles into the glaze, also will not cause too much impact on glaze colors.
(2) the effect of milling time: long ball milling time, ball mill liner wear and the big balls, impurities in the glaze, glaze on the big influence on. Especially flint lining materials and natural stone, the grinding efficiency is low, need long time milling, and its wear resistance is low, so the mixed with impurities in the glaze, glaze effects are also big.
(3) effects of milling fineness: mainly refers to the pigment fineness. Shall determine its fineness according to characteristics of color itself (see above), such as yellow, Ge Xihong and other colors, is not too fine grinding.
(4) sieving to eliminate influence of iron: iron removal through sieving is glaze slurry preparation process essential process, it can remove the iron in the glaze, glaze have great spots to avoid. But when the pigment also has magnetic, not iron removal, otherwise it will remove the color glaze, glaze color caused by the loss, the glaze color is more shallow. Not iron pigment mainly iron containing pigments, such as zirconium iron pink, red brown, black, with particular attention paid to the pigment in the above time.
(5) the glaze slurry uniformity effect: uniformity glaze slurry mixed directly affect the consistency of product glaze colors. Glaze the uniformity of poor, the product easy occurrence chromatism. If the same number of glaze in two ball milling, the best should be two times of the first milling glaze slurry in the same slurry tank after mixing evenly, and then the di
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