1.How weather-resistant is polyester?
Weather Resistance Rating: ★★★☆☆ (Medium)
Features: This is the most commonly used and cost-effective option. It has good flexibility and adhesion.
Lifespan: Noticeable chalking and fading typically begin to appear after about 5-10 years.
Suitable Applications: Roofing and wall panels for industrial plants, warehouses, and other buildings where colorfastness is not a primary concern.
2.How is the weather resistance of silicon-modified polyester?
Weather Resistance Rating: ★★★★☆ (Good)
Features: Introducing silanes into polyester resin significantly improves weather resistance, gloss retention, and anti-chalking properties compared to standard polyester.
Service Life: Up to 10-15 years.
Applications: Suitable for public and commercial buildings requiring high weather resistance; a balanced choice between polyester and PVDF.
3.How weather resistant are high-durability polyesters/super polyesters?
Weather Resistance Rating: ★★★★☆ (Good to Excellent)
Features: Through special resin formulation and pigment technology, its weather resistance approaches or even reaches the level of some PVDF, but at a more competitive cost. It represents a mainstream development trend in recent years.
Service Life: Up to 15 years or more.
Applicable Scenarios: Widely applicable, a common choice for mid-to-high-end buildings.
4.How weather resistant is PVDF (polyvinylidene fluoride)?
Weather Resistance Rating: ★★★★★ (Excellent)
Features: This is recognized as one of the best weather-resistant topcoats. Its chemical bonds are very stable, effectively resisting UV degradation, and it has excellent anti-chalking, color retention, and self-cleaning properties.
Lifespan: Typically 20-25 years or even longer.
Suitable Applications: Landmark buildings, stadiums, airports, high-end public buildings, and other projects with stringent requirements for color and lifespan.
5.What are some other important influencing factors?
Coating Thickness
Principle: The thicker the coating, the longer the protection time.
Generally, the thickness of the topcoat is a key indicator of weather resistance. PVDF coatings typically require a thicker topcoat (generally no less than 20μm), while ordinary polyester coatings are thinner.
Substrate Type and Coating
The substrate (such as galvanized steel sheet or aluminized zinc steel sheet) and its coating weight determine the corrosion resistance of the pre-coated steel coil. If the substrate has poor corrosion resistance, it will quickly corrode from the inside once the topcoat is damaged. Aluminized zinc steel sheet (such as 55% aluminum zinc) generally has better resistance to edge corrosion than ordinary galvanized steel sheet.
Application Environment
Normal Environment: Inland cities with low air pollution.
Harsh Environment: Coastal areas (high salinity, high humidity), industrial areas (acid rain, chemical pollution), high UV radiation areas (high altitudes, tropical regions). In these harsh environments, a topcoat with a higher weather resistance rating (such as PVDF) should be selected.