Why do bathroom mirrors have spots

When looking at the mirror, I found some black spots on the bathroom mirror, which affected the use of the bathroom mirror. But why the bathroom mirror is smooth and stain-free, but also has spots?

In fact, this kind of situation is not uncommon. The bright and beautiful bathroom mirrors are exposed to the water vapor in the bathroom for a long time, and the edges of the mirror will gradually darken and even gradually spread to the center of the mirror. The reason is that the surface of the mirror is usually manufactured by electroless silver plating, and silver nitrate is the main raw material. There are two cases of black spots. One is that the protective paint and silver coating on the back of the mirror peel off in a humid environment, and the mirror does not have a reflective layer. Second, in a humid environment, the silver-plated layer on the surface is oxidized to silver oxide by air. The silver oxide itself is a black substance, causing the mirror to look black.

Bathroom mirrors are cut. The exposed edges of the mirror are easily corroded by moisture. This corrosion often starts from the edge and gradually spreads to the center, so the edge of the mirror must be protected. Use glass glue or edge banding to seal the edge of the mirror. In addition, it is better not to lean against the wall when installing the mirror, leaving some gaps in favor of the vapour of mist.
Once the mirror turns black or spots, there is no way to relieve it, but the mirror can only be replaced. Therefore, reasonable use and maintenance on weekdays become very important.