Prepainted Galvanized Coated Ppgi Steel Coil Roll Q235 Q345

Product Specification

Coated sheet with 3000h gloss retention rate ≥ 50%: A key indicator of weather resistance and industry value 

In the performance indicators of coated sheets, "3000h gloss retention rate ≥ 50%" is not just a simple number; it is the core benchmark for measuring the weather resistance of the product and a direct proof of the "appearance and strength coexisting" of the material in the harsh outdoor environment. Behind this indicator lies breakthroughs in coating technology, improvements in production processes, and profound considerations for long-term usage value. 
Gloss retention rate refers to the ratio of the surface gloss of the coated sheet after a certain period of artificial accelerated aging test to the initial gloss. The 3000h duration is equivalent to simulating the natural aging process of outdoor exposure for 5-8 years, and the 50% threshold is the bottom line to ensure that the appearance and protective performance of the material do not deteriorate. For applications such as building exteriors, roofs, and outdoor billboards that are exposed to sunlight, rain, and sandstorms for a long time, this indicator directly determines whether the product can maintain bright color and intact coating over time — if the gloss retention rate is lower than 50%, it often accompanies problems such as coating powdering, fading, and cracking, which not only affect appearance but also lose the protective effect on the substrate, significantly shortening the service life. 
To achieve a 3000h gloss retention rate ≥ 50%, it is necessary to control the entire production chain from coating formulation to production process. The selection of coating raw materials is the foundation, and fluoropolymer resin (PVDF) and high weather-resistant polyester (HDP) are currently the mainstream solutions. The fluoropolymer coating, with the strong stability of carbon-fluorine bonds, can effectively resist ultraviolet degradation and chemical corrosion, and its 3000h gloss retention rate can easily exceed 70%; high weather-resistant polyester improves the molecular chain's weather resistance by introducing special monomers, achieving a balance between cost and performance, and meeting the needs of mid-to-high-end outdoor scenarios. In contrast, ordinary polyester coatings may experience a significant decline in gloss around 1500h and are difficult to meet the 3000h standard. 
Precise control of the production process is also crucial. The coating thickness needs to be uniform and meet the design standard (usually the total thickness on both sides is ≥ 60μm), too thin will result in insufficient protective layer, and too thick may cause internal stress cracking in the coating; the precise matching of curing temperature and time can ensure that the resin fully cross-links to form a dense film layer, improving the anti-aging ability; the pre-treatment of the substrate (such as zinc coating thickness, passivation treatment) will also indirectly affect the coating adhesion, avoiding coating peeling due to substrate corrosion. Data from a leading enterprise's production shows that by optimizing the curing furnace temperature curve, the 3000h gloss retention rate of its fluoropolymer coated sheet increased from 65% to 72%, and the outdoor service life of the product was extended to over 25 years. 
The popularization of this indicator is reshaping the quality competition landscape in the industry. In the construction field, using coated sheets with 3000h gloss retention rate ≥ 50% can reduce the cost of subsequent renovation and maintenance. For a 100,000-square-meter factory building, if using ordinary coated sheets, it needs to be renovated once every 10 years, with a single cost of approximately 2 million yuan; while using high weather-resistant products, the renovation cycle is extended to 20 years, reducing the total life cycle cost by nearly 40%. In the renewable energy industry, the weather resistance requirements for coated sheets for photovoltaic racks and storage equipment shells are even more stringent. 3000h gloss retention rate has become an entry threshold, driving the industry to "long service life, low energy consumption" transformation. 
With stricter environmental regulations and upgraded green building standards, 3000h gloss retention rate ≥ 50% is no longer an "optional indicator" but a "must-achieve requirement". In the future, with the application of nano-coatings and self-repairing technologies, the weather resistance performance of color-coated rolls will further surpass expectations, providing more material solutions that combine aesthetic value with durability for various fields. Behind this indicator lies the industry's pursuit of "lasting quality", and it is also a vivid illustration of the manufacturing sector's shift towards high-quality development.