What is tinplate

Tin plated steel plate, commonly known as tinplate (SPTE), refers to a cold-rolled thin steel plate coated with a thin layer of metallic tin on its surface. It has a certain strength and hardness, good formability and easy welding, the tin layer is non-toxic and odorless, and the surface is bright. Tin mainly plays a role in preventing corrosion and rust.

Tin plated steel plate (commonly known as tinplate) is a steel product made of a thin steel plate that can be stamped as a substrate, with tin plating on its surface and multiple protective films (layers). It has the characteristics of corrosion resistance, non toxicity, odorlessness, surface gloss, high strength, easy coating, easy welding and processing, as well as strong adaptability to environmental temperature.

Therefore, over 70% of the total production of tinplate is used for packaging food and beverages. In addition, it is also a packaging and raw material supplier for industries such as chemical and pharmaceutical, electromechanical, hardware, and telecommunications instruments. 

The main feature of tin plated steel plate is that the tin plating layer has dual properties of electrochemical cathode and anode protection, that is, in the inner wall of food cans containing complex mixtures (or weakly acidic hydrolysates) and having a certain vacuum,

The potential is lower than that of the base material iron, and tin acts as the anode. Its dissolution protects iron. During the shelf life of canned food, the amount of tin dissolved is basically harmless to the human body; And its outer wall is exposed to atmospheric decomposition, and the tin plating layer is in a cathodic protection state, with sufficient chemical stability, which is unparalleled by other canning materials.

There are two production methods: hot plating and electroplating. The thickness of the tin plating layer in the hot plating method is thick and uneven, and the coating thickness is difficult to control. It consumes a large amount of tin and has low efficiency, which limits its application. Therefore, it is gradually being eliminated by the electroplating method. Electroplating method is to uniformly coat a tin film on a steel plate substrate using electroplating technology.