Painting Classroom: Introduction to the special coating method of plastics
In view of the particularity of plastics and their products, in addition to industrially common brushing, roller coating, shower coating, dip coating, air spraying, high pressure airless spraying, the plastic industry also uses the following special coating methods. 1 drum coating method. Put plastic toys, daily necessities and paints with simple shapes into a round, hexagonal, octagonal and other rotating drums, and rotate them together for a certain period of time (generally several minutes to tens of minutes) to completely infiltrate the plastic surface. Take out the net, drain and bake. The viscosity of the paint should be slightly smaller. The control is in the coating of -4 cups for 16~20s. According to the diameter of the rotating drum, the rotation speed is generally 20~40r/min. The rotation speed is too fast, the product is thrown to the barrel wall, lacking its own rotation; Slow, the product is difficult to roll, and the coating film is uneven. 2 screen printing. Generally used for the printing of trademarks, high-speed roller printing is often used for plastic films. 3 electrostatic spraying. The grounded coating is used as the anode, the coating nozzle is the cathode and a negative voltage is applied, and the atomized paint droplets are sprayed with a negative charge to the positively charged plastic product. Since plastics are prone to static electricity, it is necessary to remove static electricity first in order to perform normal coating. Generally, a corona discharge type static eliminator is used, which generates a charge neutralization opposite to the plastic surface, and an uneven charge due to friction or the like. Second, the conductive surface is immersed, sprayed, showered, etc. with a conductive agent to reduce the surface resistance, so that the surface resistance of the plastic is <108 Ω. The resistance of the coating should also be controlled within 107 Ω. Concerned about surprises Label: Special coating Plastic surface Coating In addition to static electricity Rolling coating Previous: 4 special plating methods in circuit board plating Next: China's aluminum price and the pain point of the manufacturer Bathroom Sanitary Ware, Stainless Steel Sanitary Ware, Traditional Sanitary Ware, Kitchen Sanitary Ware ZHEJIANG KINGSIR VALVE CO., LTD. , https://www.kingsir-valves.com