The principle of thermos cup.

Generally, it is a water container made of ceramic or stainless steel plus a vacuum layer. The top has a cover and is tightly sealed. The vacuum insulation layer can delay the heat dissipation of the water and other liquids contained in it, so as to achieve the purpose of heat preservation. The thermos cup is generally a water container made of ceramic or stainless steel plus a vacuum layer. The top has a cover and is tightly sealed. The vacuum insulation layer can delay the heat dissipation of the water and other liquids contained in it, so as to achieve the purpose of heat preservation. The thermal insulation effect of the thermos cup is mainly manifested in that the cup is not hot, and it can ensure the isolation between the water in the cup and the outside air, so as to achieve the function of insulating water.