Metal etching has evolved from several aspects: 1: discovery and extraction of metals; 2: discovery of chemical potions; 3: emergence of anti-corrosion materials. In our life, metal corrosion generates new oxidation and disappears. From the Stone Age to the development of metal technology for thousands of years, metal smelting has extracted acid from acid-containing substances to the present chemical etching process. The modern etching process is, Steel sheet cutting → degreasing and cleaning steel sheet → ink covering → finished film covering steel sheet → image transfer and development to steel sheet → etching finished product through corrosion potion → ink demoulding → finished product.