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　　Corrode metal plate is also called etching plate. The main search using the mask, after etching process processing system to do three steps from the Braille metal plate or a concave metal plate.
　　Corrosion of metal plate production process:
　　1) Cutting: by drawing (layout size) in size, surrounded by more than plus not less than 5mm burrs. Shears with 720 foot-operated shears, the surface smooth, surrounded by non-Maori.
　　2) metal corrosion signs Finish:
　　(1) mechanical polishing: polishing machine with 2.2-4 kW of mechanical polishing wool, cloth round use motor speed is generally 300-350 2000-3000 revolution / min.
　　(2) alkali treatment: 10-15% aqueous solution of sodium hydroxide at 65-85 ℃ in the metal plate cook 10-30 seconds, and then washed with water, immersed in 5% of the weight of Ming acid aqueous solution.
　　(3) powder processing method: using a flat brush dipped in old powder (double pink) version of the child will be a uniform method of cross brush ears, except to effect until decontamination face, skin or remove oxygen, and then with a 5% aqueous solution of potassium dichromate In closed.
　　(4) The drawing processing method: using mechanical or manual drawing methods were brushed metal plate surface treatment, metal surface regeneration to achieve the effect.