Introduction to Metal Etching Process Flow

The etching process of different types of metals varies, but the general steps are as follows:

Metal etching plate → degreasing → water washing → etching → water washing → drying → screen printing → drying → water immersion for 2-3 minutes → etching pattern text → water washing → ink removal → water washing → acid washing → water washing → electrolytic polishing → water washing → dyeing or electroplating → water washing → hot water washing → drying → soft cloth polishing (polishing) → spraying transparent paint → drying → inspection → finished product packaging.

1. Pre etching treatment
The process before metal etching is pre-treatment, which is a key process to ensure good adhesion between silk screen ink and metal mask. Therefore, it is necessary to thoroughly remove the oil stains and oxide film on the metal etching surface. The oil removal plan should be determined based on the oil contamination of the workpiece, and it is best to perform electrolytic oil removal before screen printing to ensure the effectiveness of oil removal. The best etching solution should also be selected according to the type of metal and the thickness of the oxide film to ensure a clean surface. Before screen printing, it needs to be dried. If there is moisture, it will also affect the adhesion of the ink, and even affect the effect of subsequent pattern etching and distortion, affecting the decorative effect.
2. Screen printing
Screen printing requires the production of standard patterned screen printing screens according to printing needs. In the process of pattern decoration, screen printing mainly plays a protective role. When applying photosensitive adhesive, it is necessary to apply more times in order to produce thicker screen templates, which can improve the covering performance and etch patterns with high clarity. The adhesive film of the screen plate undergoes a photochemical reaction under the action of light, causing the illuminated part to crosslink into a water-insoluble adhesive film, while the non illuminated part is dissolved by water and exposes the screen space, thereby engraving a leakage pattern that conforms to the black and white positive film pattern on the coated screen plate.
Fix the silk screen with patterns on the screen printing machine, use alkali soluble and acid resistant ink to print the required patterns on the metal plate, and after drying, it can be etched.
3. Post etching treatment
After etching, the silk screen ink must be removed. General acid resistant ink is easily soluble in alkali. Immerse the etching plate in a sodium hydroxide solution of 40-60g/L at a temperature of 50-80 ℃ for a few minutes to remove the ink. After removal, if high brightness is required, it can be polished and then dyed. After dyeing, to prevent discoloration and increase wear and corrosion resistance, transparent gloss paint can be sprayed. For some metals that have good corrosion resistance and do not stain, transparent paint may not be applied, depending on actual needs.