What are the methods of plastic surface treatment?

There are many kinds of surface treatment processes for plastic materials. According to different surface treatment requirements, the common treatment methods are: painting, electroplating, water transfer printing, gluing, ink and so on. Among them, nylon, polypropylene, polypropylene, TPU, etc. It is widely used in the bonding process of spray painting, while ABS, PC and so on. Pay attention to the substrate during electroplating.

Of course, besides these surface treatment methods, there are other surface treatment methods. Here, we share the solutions to the bad surface of plastic when painting or gluing and UV vacuum coating, that is, the paint is sprayed off, the adhesion is not firm, and oil spots appear in vacuum coating.

Materials such as nylon and PP have low surface energy and polarity. Usually, poor adhesion will lead to paint peeling, which will affect the quality and effect of spraying. The traditional solution is to improve the adhesion by corona or flame treatment, but the effect is unstable and uncontrollable, and the production process is complicated. The simple and effective method is to improve the interlayer adhesion between plastic substrate and paint coating through Jingchuan plastic adhesion treatment agent to solve the problem of paint peeling, and the 100 grid test reaches 5B.

Generally, there will be no adhesion problem when ABS, PC and other materials are sprayed on the surface. However, in the electroplating process, because there are many injection processes of ABS, PC and other materials, sometimes release agent or mold oil stains are used on the surface of the materials, resulting in oil pits and oil spots on the surface. The common method is to soak in white oil or 120 gasoline, which is dangerous and the effect is not ideal. The simple and effective method is to electroplate oil pollution treatment agent through Jingchuan Chemical Industry.

The common plastic surface treatment methods are summarized and classified:

First, scrub

Frosted plastics generally refer to plastic films or sheets. When the sheet is extruded, there are frosted lines on the surface of the forming roller, which naturally form when the plastic is cooled. This method is simple and rapid, especially suitable for transparent products.

Second, polish

A machining method that uses mechanical, chemical or electrochemical action to reduce the surface roughness of a workpiece to obtain a bright and flat surface. Plastic products are generally polished with a frosted paper roll, which is generally the previous step of spraying!

Third, spraying.

Plastic spraying is mainly to coat a layer of plastic paint on metal equipment or plastic products, and then dry them. The general baking time is about 10 minute. Due to the progress of paint, the same effect can be achieved without pasting paper as before. Spray painting can isolate air, and spray painting is an insulator, so it can play the role of anti-aging and anti-static of plastic products, and most importantly, it has the appearance effect that plastic products do not have.

. In the process of plastic surface spraying, the effective method to solve the poor adhesion between substrate and coating is Jingchuan chemical adhesion treatment agent, which can improve the adhesion between substrate and coating and solve the problem of paint peeling, and the adhesion can reach 5B.

Fourth, screen printing.

Printed boards are usually square and have a fine screen shape. When printing, the ink on the printing plate leaks from the through hole of the layout to the substrate under the extrusion of the scraper. There are many materials for screen printing, such as nylon (PA), vinegar (CA), silk or metal mesh. If PC (polycarbonate) adopts this surface treatment, the color performance will be very ideal.

Verb (abbreviation for verb) transfer printing

First, the designed pattern is etched on the printing plate, then the etched printing plate is coated with ink, and then most of the ink is transferred to the printed matter through the silica gel head.

Sixth, thermal transfer printing

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 by one-step processing (heating and pressurizing) by the thermal transfer machine. After molding, the ink layer is integrated with the product surface, which is vivid and beautiful, greatly improving the grade of the product. However, due to the high technology content of this process, many materials need to be imported. Thermal transfer printing technology is applied to the surfaces of various ABS, PP, plastics, wood, coated metal and other products.

Seven, water transfer printing:

It is a kind of printing that transfer paper/plastic film with color patterns is hydrolyzed by polymer by water pressure.

Eight, laser engraving

Using the energy of laser to process the surface into a kind of "trace", exposing the next layer of material on the surface, and making carvings or patterns as needed.

Nine, electrophoresis (water electroplating)

As one of the metal electrodeposition technologies, metals such as chromium and zinc are usually used to obtain deposited layers on the surface of workpieces by electrochemistry. The exterior of the plastic part has a metallic texture, and the material is corrosion-resistant and wear-resistant, with decorative, electrical, magnetic and optical properties. The commonly used materials in electroplating process are ABS and PC. However, in the process of injection molding, if the release agent or mold oil stains on the surface of the material, it will lead to oil spots, oil pits and oil spots. The effective solution is to cover the oil stains on the surface of the material instead of soaking in white oil to improve the adhesion and solve the problems of oil spots, oil pits and oil spots.

Vacuum coating

In the vacuum chamber, the atoms of the material are separated from the heating source and hit the surface of the plated object. This method can achieve dazzling effect and is suitable for ABS and PC plastic products. At the same time, due to its complex technological process and high requirements for environment and equipment, it is generally suitable for mass products.

Eleven, bite flowers (etching, dermatoglyphics) for plastic mold.

Concentrated sulfuric acid is used to corrode the inside of plastic molding die, forming patterns such as snake pattern, corrosion pattern, plow pattern, wood grain and so on. After the plastic is molded by the mold, there are corresponding patterns on the surface.