Bone porcelain glaze color defects on 11

( 1) Flower face layer area on bone China accounted for the proportion of big volume proportion, and ware the bone China the dissolubility of lead, cadmium exceeds bid, 2) Bone porcelain color porcelain with pigment and chemical stability, corrosion resistance is not strong, 3) Bone China with flat printing decals color porcelain bake temperature to control - in 730 850 ℃ with screen printing paper color porcelain bake temperature control at 800850 ℃, in the high temperature at the same time, both 5 - not heat preservation 10 minutes ( 4) Bone porcelain kiln, on the structure of preheating zone without pores, all let the ventilation is poor, waste gas is difficult to eliminate. Barbecuing, not according to the color porcelain product size to determine the length of the heating time within bone kilns and speed into the box. When barbecuing bone kilns in upper and lower temperature difference is too big. Ways to prevent lead to dissolve quantity to exceed bid, 1) Bone China porcelain glaze to switch to lead-free glaze, such as strontium lead a boron glaze instead of boron glaze, for example: (as follows 2) Pigment developed lead-free flux. After using the following formula, for example, can the dissolubility of lead & lt; 7 PPM, but not enough bright color, luster is also poor. ( 3) Improve bone porcelain flower face design, multi-purpose lines or liquid gold decoration, use less massive flower surface, flower color color layer below area shoulds not be too great proportion in the bone China, promoting bone porcelain glaze, glair adornment. ( 4) Improve paint flux acid, the bone porcelain glaze on multi-purpose acid dye, use less acid paint. Tests showed that: under the different temperature, barbecuing various color standard, measure its dissolubility lead, found that the dissolubility of lead sequence is as follows: bean tea & lt; Iron oxide red & lt; Grey & lt; Blue, green & lt; Lattice green & lt; Black & lt; Sky blue & lt; Iron yellow & lt; No acid is iron yellow sea blue, visible and cobalt blue, therefore, improve flux acid is one of the important ways to solve the dissolubility of lead. ( 5) Developed lead-free drying oil instead of lead dryness oil is important to reduce the dissolubility flower surface lead topic, ceramic color paper when printing, prompting oil ink dry desiccant are mainly made of lead sulfate and linseed oil lead dryness oil which contain more than 70%, such as switching to drill manganese dry oil cream, although has the same effect, but for some hair color pigment, developed lead-free drying oil is subject to be studied in the future. ( 6) Improving the structure of bone porcelain kiln ceramic tunnel kiln in preheating zone and sacking pores, improve the ventilation conditions. Packing is not too close, if the temperature difference is bigger, up and down on top of burn in flat bone porcelain, floating in the hollow flower bone porcelain or simply vent is not installed, at the bottom of the baking chamber temperature segment to a steam spray gun, constantly to the furnace injection water vapor ( It is advisable to water vapor should be no water droplets) So that can effectively reduce the dissolubility of lead. ( 7) Improve the baking temperature, strengthen bone porcelain glaze and the reaction of the flux, improve the acid resistance of the flower. For example, the bone porcelain bake temperature in & gt; 800 ℃, the vast majority of bone porcelain glaze color lead on dissolution quantity can be lower than 7 PPM. With a flat printing paper color porcelain, burn should be controlled in 800 - baked 830 ℃, the screen printing decals should be controlled in 820 - Between 850 ℃. In the high temperature insulation should be 5 - 10 minutes, the dissolubility of lead high flower surface should not use the electric stove, red furnace bake to burn. As approved by testing, the roast burning decals bone China lead to dissolve a quantity to exceed bid it after the fire, such as heavy toasted proper measure can make the lead let down to standard range. ( 8) Chemical lead reduction method is used, the dissolubility of lead high bone porcelain products are soaked in 20% nitric acid solution 7 hours, can greatly reduce the dissolubility of lead, which makes the bone porcelain products to meet the use requirements. — Tangshan bone porcelain tableware completion of custom. 。 。 。 。 。