Common post-processing processes for plastic products
There are many common surface treatment methods for plastics, among which electroplating and painting are more common. The following is a comprehensive introduction to the plastic surface treatment process:
1. Frosting
Frosted plastic generally refers to plastic film or sheet. When the sheet is extruded, the surface of the forming roller has a frosted pattern. In this way, the frosted pattern is naturally formed during the cooling process of the plastic. This method is simple and fast, especially for transparent products.
2. Polishing
The processing method of using mechanical, chemical or electrochemical effects to reduce the surface roughness of the workpiece to obtain a bright and flat surface. Plastic products are generally polished by rolling up frosted paper, which is usually the previous step before spraying!
3. Spraying
Plastic spraying mainly involves applying a layer of plastic paint on metal equipment or plastic products, and then drying it. It usually takes about 10 minutes. Thanks to the progress of paint, to achieve the same effect, you don’t need to stick paper like before. Spraying paint can isolate the air, and spraying paint is an insulator, so it can play the role of anti-aging and anti-static of plastic products. The most important thing is that it has an appearance effect that plastic products themselves do not have. In the spraying process on the plastic surface, the effective way to solve the problem of poor adhesion between the substrate and the coating and paint falling is to use Jiongsheng adhesion promoter to improve the adhesion between the substrate and the coating and solve the problem of paint falling. The adhesion reaches 5B.
4. Silk screen
The printing plate is usually square and fine mesh. When printing, the ink on the printing plate leaks from the through-hole part of the plate to the substrate under the extrusion of the scraper. There are many kinds of materials for making silk screens, such as nylon (PA), polyester (CA), silk or metal mesh. If PC (polycarbonate) uses this surface treatment, the color performance will be very ideal.
5. Pad printing
First, etch the designed pattern on the printing plate, apply ink to the etching plate, and then transfer most of the ink to the printed object through the silicone head.
6. Thermal transfer
The pattern is pre-printed on the surface of the transfer film, and the exquisite pattern on the transfer film is transferred to the surface of the product through a thermal transfer machine (heating and pressurizing) in one process. After molding, the cracking ink layer is melted into the surface of the product, which is realistic and beautiful, greatly improving the grade of the product. However, due to the high technical content of this process, many materials need to be imported. Thermal transfer technology is applied to the surfaces of various ABS, PP, plastics, wood, coated metals and other products
7. Water transfer
It is a kind of printing that uses water pressure to hydrolyze the transfer paper/plastic film with color patterns.
8. Laser engraving
The surface is processed into a "trace" by the energy of the laser, exposing a layer of material under the surface, and words or patterns can be engraved as needed.
9. Electrophoresis (water electroplating)
One of the metal electrodeposition technologies, usually using metals such as chromium and zinc to obtain a metal coating process on the surface of the workpiece through electrochemistry. Make the outside of the plastic part have a metallic texture, and make the material corrosion-resistant and wear-resistant, and have decorative, electrical, magnetic and optical properties. Common materials in the electroplating process are ABS and PC, etc. However, if a release agent is used or the mold oil is rolled onto the surface of the material during the injection molding process, it will cause oil spots, oil pits, and oil spots. The effective solution is Jiongsheng electroplating oil treatment agent, which covers the oil on the surface of the material, replaces white oil immersion cleaning, improves adhesion, and solves problems such as oil spots, oil pits, and oil spots.
10. Vacuum coating
In the vacuum chamber, the atoms of the material are separated from the heating source and hit the surface of the plated large source nucleus object. This method can achieve a dazzling effect and is suitable for ABS and PC plastic products. At the same time, due to its complex process flow, high environmental and equipment requirements, it is generally suitable for large-scale products.
11. Biting (etching, leather grain) for plastic molds
Use concentrated sulfuric acid to corrode the inside of the plastic molding mold to form snake grain, etching, plowing, wood grain and other forms of grain. After the plastic is formed by the mold, the surface has corresponding grains.
