During making of thermos bottle, cleaning of the silver residue on the surface of silver coating is one important link. In the past, domestic manufacturers often use distilled water (non-ionic water) as cleaning agent thus both expenses of electricity and energy are higher. According to the invention, tap water is firstly used as the cleaning agent, as tested with pH testing paper, the effect of cleaning is attained. The process features feul-less, no electricity used, saving of the distilled water, main installations, vessels and raw material etc. |