Common metal signs include flat dry signs, silk screen signs, corrosion signs, electroplating, electroforming signs, thermal transfer signs and sandblasting signs. (1), exposure signboard: By using the method of exposure of photosensitive signboard, different colors are dissolved in the film and displayed on the metal plate through development, so as to achieve the purpose of illustration. (2) Screen-printed signs: screen-printed with resin ink on the pretreated board surface, and then made into various exquisite color screen-printed signs by processes such as gloss protection and film covering. (3) Corrosion marks: Corrosion marks are also etching marks. Mainly check the convex mark or concave mark made by mask and post-etching treatment. (4) Electroplating and electroforming sign: also known as gold piling sign, which is made by screen printing or photosensitive system. (5) Thermal transfer sign: a special panel generated by surface treatment of metal plate, and then the color picture you designed is printed on conversion paper by inkjet, and then reversed to the metal plate by heating. (6) Sandblasting signboard: By means of computer lettering, the engraved post-it notes are pasted on the metal plate, the characters and graphics are sandblasted to form a sand surface effect, and then oxidized to make the metal plate present a gold placer effect.