Why is the tin box easy to rust in a humid environment?

As a common type of packaging in the market, tin boxes have been around for a long time, but some customers have reported that tin boxes are easy to rust. I believe many people can understand this kind of situation, but the specific reasons are not very clear. As a common type of packaging in the market, tin boxes have been around for a long time, but some customers reported that tin boxes are easy to rust. I believe many people can understand this kind of situation, but the specific reasons are not very clear, so I will briefly share with you.

The material of the tin box is tin-plated thin steel plate. Due to the different metallic properties of iron and tin, the two metals are prone to oxidation reaction under natural conditions, resulting in corrosion and rusting of the iron sheet.

However, as long as you keep the well-made iron box packaging, you basically don't need to worry about this problem.

Because before the tin box is formed, the tinplate will be treated with anti-rust treatment. One is to add varnish to the printing, which not only beautifies the tin box, but also uses the ink used for printing and the varnish on the surface to double-layer protection for the iron material. Processing; the other is plain tin box, directly over varnish without printing. These two methods can well isolate the contact between the iron material and the moisture in the air, and slow down the oxidation speed of the iron material.

However, if there is rust, it means that your tin box product is placed in a humid environment. In a humid environment, the air contains a lot of water molecules, and the iron material and it are oxidized to rust. Another reason is that your tin box product is damaged, scratches or friction cause the surface to lose the protection of the ink, and the iron material is exposed to the air, and then oxidizes and rusts.