Using high-quality substrates, the requirements for the surface, shape, and dimensional accuracy of the substrate are getting higher and higher. For outdoor use, such as flat hot-dip galvanized steel coils with small spangles, flat hot-dip galvanized steel coils without spangles, and the rising zinc alloy hot-dip coils; indoor use such as electro-galvanized steel coils, film-coated cold-rolled sheets, and aluminum coils. Improving the pretreatment process and pretreatment liquid, reducing the number of equipment and low cost has become the mainstream process, and constantly improving the stability, corrosion resistance, and environmental performance of the pretreatment liquid. Pay attention to the development of new coatings, improve general polyester, polyvinylidene fluoride (PVDF), and plastisol to obtain super color reproducibility, UV resistance, sulfur dioxide resistance, and improve corrosion resistance; develop pollution resistance, heat absorption, and other functions. The unit equipment is more complete.

Color-coated coils use new welding machines, new roller-coating machines, complete curing ovens, and advanced automated instruments. Since cold embossing is cheaper than hot embossing and has the characteristics of beautiful appearance, three-dimensional effect, and high strength, cold embossing production technology has become a development trend. Pay attention to the diversification, functionality, and high-end products, such as deep-drawing color-coated boards, "grapefruit peel" color-coated boards, anti-static color-coated boards, pollution-resistant color-coated boards, high heat-absorbing color-coated boards, etc. Different primers have certain differences in adhesion, toughness, and corrosion resistance. Epoxy has good bonding strength with the substrate and has high corrosion resistance, but its toughness is not as good as other primers. Polyester has good bonding strength with the substrate and excellent toughness, but its corrosion resistance is not as good as epoxy. Polyurethane is a primer with good overall performance.

The primer is usually selected by the supplier based on the production process, usage, corrosiveness of the use environment, and matching relationship with the topcoat. Different topcoat types differ in hardness, flexibility, adhesion, durability, etc. Polyester is currently a widely used coating with average durability, good hardness and toughness, and moderate price. Silicone-modified polyester has high durability, gloss, and color retention, but its toughness is slightly reduced. High-weather resistance polyester is more cost-effective. Polyvinylidene fluoride has excellent durability and good toughness but has low hardness, few available colors, and a high price.