1.What are matte and glossy finishes on galvanized color-coated steel coils? What are their key differences?
Matte and glossy finishes are two different gloss levels on the surface of color-coated steel coils, primarily determined by the coating formulation. Their core difference lies in the different ways the surface reflects light, resulting in drastically different visual effects:
Glossy: The surface is smooth as a mirror, reflecting light strongly, resulting in a vibrant and impactful visual appearance. High-gloss surfaces have a high reflectivity to sunlight during the day, potentially causing light pollution.
Matte: The surface is microscopically rough, scattering light evenly through diffuse reflection, resulting in a softer, less glaring visual appearance with a misty texture.
2.Are there specific quantitative standards for matte and glossy finishes? How are they measured?
Yes. According to the national standard GB/T 13448-2019, the gloss of color-coated coils is measured by 60° specular gloss and expressed in gloss units (GU).
3.What are the advantages and disadvantages of matte and glossy finishes? What are their respective suitable application scenarios?
Glossy
Advantages: Vibrant colors, strong decorative effect, enhances product texture.
Disadvantages: Prone to light pollution outdoors; low surface friction coefficient, making application slippery; easily shows scratches and stains; may cause glare indoors leading to visual fatigue; noticeable difference between new and old panels during repairs.
Suitable application scenarios: Suitable for interior and exterior decorations seeking a glossy finish or buildings requiring high vibrancy; also commonly used in home appliances and furniture.
Matte
Advantages: Soft light, visually comfortable and non-glaring, especially suitable for indoor use; effectively covers minor surface defects and is stain-resistant.
Disadvantages: Colors are not as vibrant and saturated as glossy finishes; may chalking occur after prolonged outdoor use.
Suitable application scenarios: Widely used in building exteriors and roofs; also suitable for interior walls and transportation facilities where visual comfort is important.
4.What are the differences in durability and aging performance between matte and glossy coatings?
Durability is primarily determined by the type of coating, but gloss affects the visual appearance after aging. The most obvious sign of outdoor aging in coatings is "loss of gloss."
Glossy: After aging, glossy panels show a more significant decrease in gloss, and due to the large contrast in gloss loss, it is very easy to distinguish between old and new panels during repairs.
Matte: After aging, the visual difference between matte and new panels is smaller, making it easier to achieve a harmonious appearance after repairs.
Among weather-resistant coatings, regardless of whether it is matte or glossy, fluorocarbon coatings (PVDF) offer the best gloss and color retention, but are the most expensive; high-durability polyester coatings (HDP) and silicone-modified polyester coatings (SMP) also have excellent gloss retention.
5.When choosing between matte and glossy finishes, what key factors should be considered besides appearance?
The following key factors should be weighed comprehensively:
Safety factors: For outdoor rooftops and other high-altitude applications, matte finishes are recommended. High-gloss surfaces can cause slippery surfaces for workers, posing a safety hazard.
Environmental factors: In areas with strong sunlight, glossy finishes can cause light pollution; in areas with high humidity and heavy pollution, glossy finishes are more likely to show water stains and dirt, resulting in higher maintenance costs.
Cost factors: Under the same coating system, matte coatings are generally more cost-effective than glossy finishes.