Bone porcelain glaze 07

Bone China leadless fritted glaze lead fritted glaze as bone China ( Bone China) Main glaze has been used for a long time, but as people living standard unceasing enhancement, depth of the increasingly attention to health, the environment, to the bone porcelain glaze production put forward higher requirements more stringent standards in many places have restrictions on the use of heavy metals such as lead, cadmium. Bone China leadless fritted glaze not use lead compounds, both to protect the people's health, and improve the production environment, fundamentally eliminate the dangers of lead, to meet the needs of the present, has a broad application prospect. Bone China ( 1) Bone China leadless fritted glaze composition in lead glaze glass network structure, the lead is an important network adjustment, its strong function and high flux density, lead has a lower surface tension, low temperature viscosity, wide firing range, high refractive index and good resistance to fracture, so in many high temperature burning, low temperature burning glaze bone China is widely used since the medium and long term. To make bone porcelain leadless fritted glaze, the first thing to solve the problem of the replacement of lead. Bone China ( 2) The substitute of lead in the lead-free frit, people commonly used Li2O, (SrO) SrO, ZnO, BaO instead of PbO, adopt industrial Li2CO3, SrCO3, ZO, BaCO3 is commonly used to introduce basic clinker composition of molten property in order of decreasing as: Li2O > Na2O > K2O > BaO > CaO > (SrO) SrO > Mgo style > ZnO commonly used alternative to lead as follows. 1) lithium in bone porcelain production, more use of lithium carbonate, slightly soluble in water, it is not hygroscopic, not agglomeration, easy to save, under normal conditions can be used directly to bone porcelain glaze materials production. Lithium mineral joins overmuch, easy to cause crystallization, combined with lithium products more expensive, generally no more than 3% ( Li2CO3) 。 In order to reduce the high temperature of clinker viscosity as the Li2CO3 join the frit. Bone China (2) in the production of strontium bone porcelain, strontium carbonate is commonly used, it has no poison, slightly soluble in water, can be directly used in raw bone porcelain glaze ingredients in clinker can decrease the high temperature viscosity, no more than 10% for the amount of general. Due to the short development history of strontium compounds, less people know about its performance function, and the price is more expensive, at present in the bone porcelain industry is not too widely used. Bone China (3) zinc zinc oxide used in bone porcelain high temperature glaze, more less in the high temperature stage of zinc oxide are the important flux it can expand the glaze melting range, improve the modulus of elasticity, reduce the coefficient of expansion, reduce cracking phenomenon. Zinc oxide is a good crystalline glaze materials, excessive zinc oxide can cause analysis phenomenon, the general control within 10%. Bone China in the production of bone China, the zinc oxide into the frit. Direct use of zinc oxide, calcined needed to reduce & other; Roll glaze & throughout; Such as bone porcelain glaze defects. The characteristics of bone China (4) barium barium similar to lead. Barium glaze have higher refractive index, can increase bone porcelain glaze gloss on the elastic and mechanical strength of bone porcelain glaze can produce beneficial effect. In the process of firing, can reduce the influence of atmosphere of bone porcelain glaze. Although toxicity than lead, barium compounds are also toxic, use less as far as possible, in use in the production of bone China, will introduce a barium carbonate directly in the frit, usage is generally not more than 6%. Bone China ( 3) Bone China lead-free frit composition & ndash; Bone porcelain cup dish to be continued. 。 。 。 。 。