1.What are the core evaluation dimensions?
Gloss Loss Rate: The percentage decrease in gloss of the coating surface. High-performance coatings experience slow gloss loss.
Color Change (ΔE): Measured using a colorimeter. A smaller ΔE value indicates better color retention. Typically, ΔE < 2 (difficult to detect with the naked eye) is required.
Chalking Grade: The℃to which the resin on the coating surface degrades into powder. Ratings are based on ASTM standards (0-10), with higher grades indicating less chalking.
Adhesion: The retention rate of the bond between the coating and the substrate after aging.
Cracking/Blistering: Directly observing whether physical damage occurs on the coating surface.
2.What are the authoritative testing methods and the "accelerated aging level"?
Common Standards: ASTM G155, ISO 16474-2
Interpretation: Suppliers will provide data such as "After 2000 hours of xenon lamp aging test, ΔE < 3, gloss retention > 80%, no chalking." The longer the test hours and the better the performance retention, the higher the weather resistance rating.
Common Standard: ASTM G154 (UVA-340 lamp tube best simulates solar ultraviolet light)
Interpretation: Commonly described as "No cracking or blistering after 3000 hours of QUV testing, chalking level >= 8." Again, the number of hours is a key comparison parameter.
3.What are the main applications and characteristics of polyester coating?
The most common type, low cost, rich colors, suitable for walls, etc.
4.What are the main applications and characteristics of silicone-modified polyester coatings?
It has better weather resistance than PE and better gloss retention, and is often used for roofing and walls.
5.What are the main applications and characteristics of high-durability polyester coatings?
Clearly define technical specifications: Specify the substrate type (AZ150 aluminum-zinc coated steel), coating system (PVDF/HDP), film thickness, color standards, and required weather resistance test indicators in the procurement contract.
Select reliable suppliers: Choose large-scale color-coated steel sheet manufacturers with experience in railway projects and a sound quality management system.
Focus on system design: A sound barrier is a system; besides the panels, the quality and design of its support structure, seals, and sound-absorbing materials are equally important.