The application of light curing coating in vacuum coating

Vacuum coating technology began in the 1930s and went into industrial applications in mid-20th century and  large-scale production in the 1980s.Then it has been widely used in the electronics, aerospace, optical, magnetic, construction, machinery, packaging, decoration and other fields, and plays an increasingly important role. Vacuum coating technology and organic composite coating is a widely used compound surface treatment technology, has several decades of development history, especially in the plastic, metal substrate preparation protective - decorative coating has been formed so great scale of production. Organic polymer coating liquid curing a variety of ways, including using UV-curable coatings (referred to as light-cured paint) increasing people's attention. Its main features are: fast curing, typically UV light radiation in just a few seconds or tens of seconds can be cured completely; environmentally friendly, when in the light most or most of the components involved into the cross-linking polymerization film; save energy, UV light curing of solvent-based coatings with energy of about 1 / 5; can paint a variety of substrates, to avoid heat curing at high temperature on the heat-sensitive substrates (such as plastic, paper or other electronic components, etc. ) may cause damage; low cost, due to substantial energy savings, high levels of the active ingredient in paint and simplify the process, significantly reduce the plant footprint and reduce production costs and other factors. The above analysis shows that light-curing of the coating in the vacuum coating industry has broad application prospects. Light-cured coatings in vacuum before and after coating and surface coating as a base coat, plays a very important role.Currently plastic vacuum coating and organic coating curing compound, commonly used vacuum aluminum coated zinc oxidewith an organic light-cured composite, but in the protection, and performance has been greatly restricted. Vacuum chrome is one of the future directions of development. Vacuum chrome aluminum coating layer has more beautiful than silver metallic luster, in the atmosphere has a strong passivation properties, in alkali, nitrate, sulfide, carbonate, organic acids and other corrosive media, stable, and high hardness , good wear resistance and heat resistance. However, the melting point of chromium is 1900 , 1397  when the chromium in the vapor pressure of 1.33Pa, high evaporation temperature of chromium, chromium-plated with vacuum evaporation more difficult. If using magnetron sputtering, due to chromium brittle, difficult to make cylindrical target, then in general the sputtering conditions, the planar magnetron sputtering target frame material due to pollution and other reasons, the color of chromium plating significant deviation from the silver-white. The authors tested research, the use of cathodic arc ion plating with a combination of ion bombardment plating method, to obtain the same color with chrome plating. In this, the choice of base coat must have sufficient heat resistance and radiation resistance, and vacuum coating and the substrate layer has a good combination of strength, not a chemical reaction with each other and have a good leveling, in the under vacuum only a few of the volatile components and do not absorb moisture, highly smooth surface after curing, etc. Among the coatings, titanium dioxide coating,  polybutadiene coatings can basically meet the above conditions, but this coating is heat cured coatings, and high curing temperature, curing time is long, can not be used for plastic vacuum coating. Alicyclic epoxy resin is a branch of the epoxy groups in its structure, not from propylene oxide, but directly connected alicyclic, so the performance compared with bisphenol A epoxy resin comparison, has a good thermal stability, weather resistance, safety, process performance and excellent insulation properties. However, alicyclic epoxy resin is the same as with ordinary epoxy resin, with a crisp shortcomings, so in practice should seek to tougheningAfter vacuum coating usually coated surface coating, vacuum coating layer of protection. Across the coating of the basic requirements are: and vacuum coating layer (usually metallic coating) and good adhesion, the coating after curing without large internal stress, and at the end of the coating has some compatibility with sufficient hardness, scratch resistance, abrasion resistance, high water resistance, corrosion resistance, weather resistance, chemical resistance and other properties, have appropriate viscosity and good leveling. For the need to highlight the color of the vacuum coating layer, the surface coating should have a high visible light transmittance and surface gloss. For the vacuum chrome surface coating layer of light-curing, has yet to find the ideal varieties, the main problem is: chrome layer with poor adhesion, hardness, wear resistance, weather resistance and other products can not meet the high demand. Current research is to improve the formulation, modification and use of nanoparticles of inorganic coating the appropriate choice.The mixture of organic light curing coating and vacuum plating is a widely used compound surface treatment technology. Vacuum chrome coating has higher requirements on light-curing coating: sufficient heat resistance and radiation resistance, and vacuum coating and the substrate layer has a good combination of strength, not a chemical reaction with each other, with good flow level and so on. Alicyclic epoxy modified acrylic paint basically meet these requirements, so as to require the use of vacuum chrome, and ion plating and magnetron sputtering vacuum coating to create the basic conditions. Organic light-cured composite chrome coating and vacuum, with the protection of titanium dioxide film, forming a new chrome technology, its performance was significantly better than a vacuum aluminum plating, chrome plating with conventional compared to the environmentally friendly, energy, water and materials, simplify processes, reduce costs and better performance characteristics, it is worth promoting.Source:http://www.mhcocm.com