Bone porcelain glaze 06

Frit ( 1) Frit role in bone porcelain production, some soluble ( Sodium carbonate, borax, boric acid, etc. ) Toxicity ( Red lead) Such as material, if use will not only cause a harm to human body directly, and bone China product quality is not stable. In the process of bone porcelain glaze dry some soluble salt will be focused on the billet edges, these parts will be affected in the process of firing, unable to get a smooth bone porcelain glaze. Another bone porcelain body surface flux, fused closed early, bone China billet in high temperature volatiles after gasification will be nowhere to rule out on the surface of bone porcelain body to form bubbles so, generally used to the raw material is made of molten. Bone China ( Bone China) Production mostly use secondary firing process, the bone porcelain glaze generally use fritted glaze. Bone China fritted glaze of general frit and suspending agent. Clinker is the most mature of temperature below 1150 ℃ has not used in industry. For bone China fritted glaze usually have corresponding water-soluble, ceramic fritted glaze long stored there will be a part of the solutes that affect bone porcelain glaze quality, for most of the frit should not be stored for a long time. ( 2) The classification of the frit (1) according to the lead or not frit is generally divided into leaded frits and lead-free frit. Bone China (2) by using temperature can be divided into high temperature frit ( 1050~1180℃) And low temperature frit ( 800~1000℃) 。 Bone China (3) according to the use of blank points can be divided into daily porcelain frit and building ceramic frit. Bone China (4) according to the color or not points can be divided into colorless transparent frit and coloured clinker, etc. Bone China ( 3) The configuration of the frit principle the following principles should be paid attention to when designing frit bone China (1) water soluble substances, toxic substances shall all be into the frit ingredients into melting block. Bone China (2) made of frit is not soluble in water. (3) in the frit RO2 and B2O3 equivalent to the sum of R2O and RO number of molecules of the ratio between the two should be the sum of ( 1 ~ 3) : 1, to ensure that the appropriate melting degrees, when melted won't because temperature is too high and volatile alkali metal oxide and PbO, etc. Bone China (4) in the frit R2O: RO< 1. (5) frit ingredients of SiO2: B2O3 & gt; 2 because of boric acid salt solubility, silicon oxide can reduce solubility. 6 frit ingredients of Al2O3 & lt; 0. 2mol。 Al2O3 too much frit ingredients of high melting temperature, melting system when the volatilization loss is big. ( 4) Frit according to the usage of clinker, the use of bone porcelain fused glaze generally fall into the fritted glaze and half fritted glaze ( Part of the fritted glaze) 。 The fritted glaze is in addition to the organic suspending agent in phalanx enamels, no longer add other mineral raw materials all use fritted glaze. Half fritted glaze is the part using the finger bone porcelain glaze frit, also add such as mineral raw materials, such as the suzhou soil or other chemical raw materials, used for ceramic glaze glaze slurry suspension and adjust the effect, and so on. Bone China fritted glaze preparation, whether it is a complete fritted glaze or half fritted glaze, using compound frit, the advantage is: one is to use two or more frit, can make the formula of stability is good, not because a clinker quality fluctuations affect bone porcelain glaze quality; The second is to use compound frit, bone porcelain glaze some relatively good adjustment, relatively wide range. Bone China lead fritted glaze in the 20th century, bone China, Bone China) The fritted glaze use lead fritted more, at the beginning of the 21st century, as countries restrictions over the use of lead, lead the bone porcelain glaze has been phased out. In view of this, and most of the textbooks have discussed more, here no longer is introduced in detail. — Tangshan bone plate to be continued. 。 。 。 。 。