2024-06-05
In recent years, imitation porcelain bowls have become the first choice for many families, especially those with children, because of their colorful colors, rich shapes, high gloss and relatively strong resistance to breakage. It is not easy for children to break during use, which undoubtedly greatly reduces the risk of kitchen accidents for parents. However, while pursuing economic benefits, some consumers often choose extremely low-priced imitation porcelain bowls from vendors in the market, such as bowls priced at 3 yuan or 5 yuan each. And such a choice may bring hidden dangers to their family's health.
Let’s understand how melamine bowls are produced. Its main raw material is melamine, also known as melamine formaldehyde resin. This thermoset plastic is mainly made from melamine and formaldehyde. Regarding melamine, this is a compound first synthesized by Liebig in 1834. In the preparation process, calcium cyanamide is prepared from calcium carbide, which is then hydrolyzed and dimerized to form dicyandiamide, which is further heated and decomposed to obtain melamine.
When melamine reacts with formaldehyde, a polymer with a linear structure and a low degree of polymerization is first formed, and then condensation polymerization continues under heating conditions to form a melamine-formaldehyde resin with a network structure. This resin itself has many excellent physical and chemical properties, such as impact resistance, corrosion resistance, the ability to withstand high temperatures (up to +120 degrees) and low temperatures, a dense structure and easy dyeing. This makes it widely used in various industrial fields.
However, in actual production, manufacturers choose different melamine formaldehyde resin raw materials, such as A1, A3, A5, A8, etc., in order to meet different usage needs. Among them, A1 and A3 are mainly used in industry, while A5 and A8 are used in food-grade applications.
A1 material, because its main ingredients contain a large amount of additives and starch, is not only toxic but also unstable at high temperatures. Its appearance is also relatively rough and prone to deformation and fading. Although A3 material is similar to A5, it also has problems of discoloration, deformation and corrosion resistance when used.
On the contrary, A5 and A8 are ingredients recognized by the country as safe for catering purposes. A5 is pure melamine formaldehyde resin, non-toxic and high temperature resistant, while A8 is mainly made of natural mineral powder and is more environmentally friendly.
But the problem is that even for melamine bowls made of A5 and A8, if the production process is not properly controlled, such as mixed raw materials, improper use of dyes, or other uncertified ingredients added during the manufacturing process, it may cause Contamination of food by tableware.
There are also some melamine tableware on the market with bright colors and rich patterns. Although very attractive in appearance, consumers should be wary. Because these brightly colored tableware may use harmful chemical dyes. In particular, some red, blue and green tableware often need to add a large amount of heavy metals such as chromium, zinc and copper during the production process. When these heavy metals accumulate in the human body to a certain extent, they may cause various diseases.
For purchased melamine tableware, if you find any abnormality during use, such as a pungent smell, the tableware turns black, or the tableware becomes hot after putting hot water in, you should stop using it immediately.