Phosphor-less hexavalent chromium-less environmentally-friendly plastic electroplating method

Abstract

The invention provides a phosphor-less hexavalent chromium-less environmentally-friendly plastic electroplating method. The phosphor-less hexavalent chromium-less environmentally-friendly plastic electroplating method comprises the following steps of 1, cleaning and drying the surface of a plastic base, 2, in a continuous vacuum film-electroplating device, carrying out plasma surface modification and metal conducting layer physical vapor deposition on the surface of the dried plastic base, 3, carrying out chemical modification on the metal conducting layer obtained by the step 2, 4, carrying out copper electroplating on the chemically-modified plastic base in a low-surface tension, phosphor-less and alkaline ultrasonic copper-electroplating solution, 5, further carrying out bright acid copper electroplating and nickel electroplating on the plastic part subjected to alkaline copper-electroplating, and 6, carrying out trivalent chromium sulfate electroplating on the plastic part subjected to bright acid copper electroplating and nickel electroplating. The product obtained by the phosphor-less hexavalent chromium-less environmentally-friendly plastic cement electroplating method has bright appearance, big coating bonding force and strong corrosion resistance and satisfies total quality requirements.

Description

technical field [0001] The invention belongs to the field of plastic electroplating, and in particular relates to an environmentally friendly phosphorus-free and hexavalent chromium-free plastic electroplating method. Background technique [0002] Plastic electroplating products not only have a good metal texture, but also have the advantages of light weight and good corrosion resistance. Plastic electroplating technology has been widely used in various industrial fields such as sanitary ware. The traditional plastic electroplating method needs to go through steps such as roughening, activation, electroless nickel plating, pyrophosphate copper plating, acid copper plating, nickel plating, and hexavalent chromium plating. Among them, roughening and hexavalent chromium plating processes require the use of hexavalent chromium. Hexavalent chromium is highly toxic and carcinogenic, and has serious harm to the human body and the environment; electroless nickel plating and pyropho...

AI Technical Summary

Problems solved by technology

Hexavalent chromium is highly toxic and carcinogenic, and has serious harm to the human body and the environment; electroless nickel plating and pyrophosphate copper plating are both electroplating processes containing phosphorus. Phosphorus is the key nutrient that causes water eutrophication, and water eutrophication Algae blooms will not only lead to the rapid growth of algae in the water, but also will cause a sharp drop in the oxygen content of the water, affecting the survival of aquatic organisms such as fish, and even causing disastrous ecological abnormalities

This method avoids the use of hexavalent chromium roughening process, but its production cost is high, and it is difficult to achieve metallization for products with complex surfaces

[0004] Chinese patent CN102127764A discloses a method of semi-dry electroplating on the surface of plastic substrates. This method uses physical vapor deposition to metallize the plastic surface, but the metal film layer obtained by physical vapor deposition has not undergone electrocrystallization. The layer is prone to crack defects, coarse grains, etc., such as figure 1 As shown, the subsequent electrodeposition will easily lead to undesirable phenomena such as pitting and pinholes in the appearance of the coating.

However, there are four shortcomings in the actual production and operation of the above-mentioned device: 1. The flexible stainless steel cracks or breaks after a period of bending, which seriously affects the production; 2. There are many transition chambers in the device, the utilization rate is low, and the floor area is large; 3. . The flapper valve between each individual furnace operates under high vacuum conditions for a long time, and the valve cannot be locked easily, which is likely to cause mutual air leakage and bring hidden dangers to the stability of the production process; 4. Due to the problem of transmission rhythm , it is impossible to install a low-temperature trap, which reduces the vacuuming speed of each single furnace; 5. The deposition efficiency of the device is low by using an intermediate frequency power supply during the coating process

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