There are two kinds of glass liners: silver plating and copper plating, and the copper plating will appear red. There is also a kind of glass liner that contains selenium beneficial to human body, so it will appear red, which is a normal phenomenon. The bottle liner is double-layered, and the inside is evacuated, so the heat inside is not easy to transfer.
The periphery of the inner layer of the liner is also plated with metallic silver, and the heat of hot water in the bottle liner will be reflected back by the silver mirror in the process of outward dissipation, which can also play a role in heat preservation. The inner coating of bottle liner is generally silver plated (silver mirror), which is silver mirror reactive plating. There are also bottles with aluminum plating (aluminum mirror) or ion vacuum coating (tungsten mirror or titanium mirror).
Please note when using the thermos cup:
1, because thermos cups have heat preservation effect, especially some good quality thermos cups have particularly good heat preservation effect. If you put very hot boiling water in it, it will still be very hot when poured out, so take medicine in a thermos cup to prevent burns.
2. It is recommended not to use thermos cups to hold greasy liquids such as soup. If the soup is not cleaned in time, it will have a serious oily smell. No matter what method you use to remove it, it is difficult to remove the greasy smell.
3. Don't use steel wire to clean the thermos cup, which will damage the cup body inside the thermos cup and affect the insulation effect, so don't use the thermos cup to hold things that are difficult to clean.