The quality standards of ceramic tableware

Ceramic tableware is family widely used tableware, but the quality of the products on the market the good and bad are intermingled, what is the quality standards of ceramic tableware? Let's look at. Appearance quality standard: the appearance quality is one of the important indicators of product hierarchy, the current products nonconforming product standard products can be divided into classy article, first class, 3 classes. Classy article is equivalent to the international level of * * * *, one for domestic * * * * level, products for the domestic average. Classy article the appearance quality of basic has reached the requirement of 'five no', namely, no spots, no residue, colorless, pinhole, glazed scratches, dirty little deformation. Spot ( Black spots) Commonly known as fly shit, if there are spots on products, always give a person the sense with impurity, which affect the appetite. Grade a nonconforming product and are larger than classy article on allow defects in loose requirements. The dissolubility of lead, cadmium standards: the dissolubility of lead, cadmium is one of the important safety and health indicators ceramic products. The presence of lead, cadmium is due to the product surface decorative pattern in the ceramic pigment found in its composition, caused by the presence of lead and may be to reduce the product surface glaze firing temperature and joined the lead composition. If the improper control of production process, easy to cause in the process of using excessive dissolution of lead, cadmium, often use this kind of product is easy to cause the heavy metals lead, cadmium poisoning. The national standard GB12651 - 2003 'ceramic products in contact with the food lead, cadmium dissolution quantity allowed limits is a national mandatory standard, its applicable scope covers all ceramic eating utensils. Any single product prescribed standards of lead, cadmium dissolution quantity are not allowed to exceed the prescribed value, including flat products, From inside the products * * * * plane to mouth edge level of depth is less than 25 mm below products) Specified value as follows: the dissolubility of lead cadmium dissolution 7 mg/l, quantity of 0. 50mg/l; Small hollow products ( * * * * plane from inside the products to the mouth edge level greater than or equal to 25 mm, the depth and the capacity of less than 1. 1 l of products) E. is: the dissolubility of lead 5. 0 mg/l, the dissolubility of cadmium 0. 50mg/l; Large hollow products ( * * * * plane from inside the products to the mouth edge level greater than or equal to 25 mm, the depth and capacity greater than or equal to 1. 1 l of products) The specified value for: 2 the dissolubility of lead. 5 mg/l, the dissolubility of cadmium 0. 25mg/l。 Thermal stability criteria: thermal stability refers to the products in the cold and heat exchange, cracks or damage. Thermal stability is good or not can reflect the service life of the ceramic products, the greater the temperature difference of heat transfer, the longer its service life. Standards are usually heated to 180 ℃ and then put into 20 ℃ water, remove observe whether have damage, the temperature does not appear damaged, its service life can reach 2 ~ 3 years. Source: website administrator