Kettle:
The kettle liner refers to the inner liner of a rice cooker. At present, the main materials are: aluminum, stainless steel, composite multilayer materials and ceramics (purple sand).
Surface treatment of inner container:
The surface of the liner is treated to ensure that the contact part between the liner and food meets the food hygiene standards, and to improve the non-adhesion of the liner. At present, the surface treatment technologies used in the liner mainly include the following:
1, spray silicone anti-sticking material on the surface of aluminum liner.
Anti-sticking coating with primary silicon has a certain protection and anti-sticking effect, and its cost is low. It was widely used in the inner container of early rice cookers, but it is still used in some low-grade pots at present.
2, spraying organic krypton paint on the surface of the aluminum liner
Organic fluorine paint is the main raw material for protecting the surface of the inner container at present. An incident once labeled the fluorine paint as "toxic" that could not be torn off. In fact, in the Teflon incident in 2004, the original murderer who accused Teflon of being harmful was ammonium perfluorooctanoate (PFOA), a key raw material processing aid in Teflon manufacturing process. Ammonium perfluorooctanoate is the ammonium salt of perfluorooctanoic acid. Perfluorooctanoic acid is a soap-like substance, which can be used to make anti-fouling surfaces and various consumer goods. As a processing aid, it is added to fluoropolymer concentrated emulsion in an amount of about four thousandths (based on the amount of fluoropolymer resin). The decomposition temperature of ammonium perfluorooctanoate is relatively low, and it begins to decompose from 130℃. PTFE fluorocarbon coatings must be baked at the high temperature of 380℃-420℃, and the requirements are very strict. The temperature difference should be controlled within 5℃, and most fluorocarbon coatings should be sprayed 2-3 times,1-2 times. PFOA has evaporated at such a high temperature, so it is impossible to contain ammonium perfluorooctanoate in the coating of cooker.