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White aluminum coil stock, also known as white pre-coated aluminum trim coil, refers to industrial raw material coils made from aluminum alloy coils, coated with a uniform white protective coating using a continuous roll coating process. As a standardized industrial raw material, white coil stock is primarily intended for downstream manufacturing enterprises' stamping, bending, rolling, and deep drawing processes. Unlike finished decorative aluminum coils used directly in the construction industry, its core positioning is "a pre-coated, formed processing substrate," making it a common core material in industries such as home appliance manufacturing, lighting fixtures, ventilation ducts, cleanroom equipment, and hardware stamping.

The substrate system includes three alloy types: AA1050-O, AA3003-H14/H24, and AA5052-H32. AA1050 pure aluminum boasts excellent plasticity and high ductility, suitable for deep-drawing applications such as lamp reflectors and complex metal stretching parts. AA3003 aluminum-manganese alloy offers balanced overall performance and outstanding rust resistance, making it the primary choice for general mass production. AA5052 magnesium-aluminum alloy offers higher strength and excellent salt spray resistance, suitable for outdoor equipment housings and components used in highly corrosive coastal environments. Standard thicknesses range from 0.2mm to 1.5mm, with widths customizable for precision cutting. Thickness tolerance is controlled within ±0.02mm, and surface flatness is ≤0.3mm/m, free of sand holes and wave deformation. It can be directly integrated into high-speed automated production lines without secondary cutting and leveling.

The white coating utilizes a double-coat, double-bake continuous roller coating process to create a multi-layered protective structure. The coating undergoes a three-step process of chemical passivation pretreatment, epoxy sealing primer, and weather-resistant polyester topcoat, followed by high-temperature curing. The topcoat dry film thickness is consistently 20–30 μm, while the back protective primer thickness is ≥8 μm. The coating exhibits thorough cross-linking, resulting in a dense and uniform finish. Colors of white aluminum trim coil matching adheres to internationally recognized color standards, with three industry-standard color codes readily available: RAL9003 Signal White, RAL9010 Pure White, and RAL9016 Traffic White. A fully automated closed-loop color matching and online color measurement system ensures a color difference ΔE ≤ 1.0 within the same batch and ΔE ≤ 1.5 across batches. Mass production is free from color fluctuations, eliminating the need for downstream companies to repeatedly adjust colors and produce samples.

In terms of performance, the coating adhesion meets ASTM D3359 4B standards. The coating does not crack or peel after deep drawing, bending, or stamping, perfectly adapting to various forming processes. The formula incorporates anti-yellowing agents and UV absorbers, effectively addressing the industry pain point of light-colored coatings easily yellowing. Testing showed a color difference ΔE ≤ 2.5 after 1000 hours of accelerated aging under xenon lamps, and no blistering or rust after 1000 hours of neutral salt spray testing. It maintains stable color in indoor environments and has a service life of 8-10 years under normal outdoor conditions. The coating surface is dense and smooth, resistant to oil stains, and easy to clean, making it suitable for high-hygiene environments such as food processing equipment and cleanrooms.

Compared to the traditional "post-forming spraying" production model, white aluminum coil stock can be directly machined, eliminating the need for spraying, drying, and waste gas treatment. This significantly shortens the production cycle for downstream companies, reduces environmental protection investment and overall manufacturing costs, while also providing significantly better coating uniformity and yield than manual spraying. Aluminum itself is lightweight and 100% recyclable, aligning with the global trend of green and low-carbon manufacturing. Currently, white coil stock is widely used in home appliance housings, lighting fixtures, ventilation ducts, cleanroom wall panels, hardware stamping parts, equipment covers and other fields, and is the core material choice for lightweight upgrading and cost reduction and efficiency improvement in the global manufacturing industry.