Polyester Coated Aluminum Sheet
Polyester coated aluminum sheet is an aluminum substrate coated with a polyester resin paint system through continuous coil coating or sheet coating. It combines the light weight, corrosion resistance, and workability of aluminum with a smooth decorative surface available in solid colors, metallic finishes, matte textures, and custom patterns.
This material is widely selected for roofing, ceilings, wall cladding, sign boards, household appliances, composite panels, and general architectural decoration. Compared with bare aluminum, the polyester coating improves surface appearance, handling resistance, and color consistency. Compared with PVDF coating, polyester coating is usually more economical and well suited to indoor use, short-to-medium outdoor exposure, and projects that require attractive color at controlled cost.
Product Character
Polyester coated aluminum sheet is produced by cleaning and pretreating aluminum, applying primer, baking, applying polyester top paint, and curing the coating under controlled temperature. The finished sheet has stable gloss, good adhesion, and reliable bending performance.
| Item | Description |
|---|---|
| Product name | Polyester coated aluminum sheet |
| Common name | PE coated aluminum sheet, prepainted aluminum sheet |
| Base metal | 1000, 3000, 5000 series aluminum alloy |
| Coating resin | Polyester, modified polyester, high-durability polyester on request |
| Surface finish | Glossy, matte, satin, embossed, brushed look, wood grain look |
| Standard colors | White, black, grey, red, blue, green, champagne, silver |
| Custom colors | RAL, Pantone, customer sample matching |
| Main use | Interior decoration, signage, roofing, ceiling, ACP, appliance panels |
For customers comparing different prepainted options, PE Color Coated Aluminum Sheet is often chosen when color variety, easy forming, and economical coating performance are the main purchasing factors.
Main Advantages
- Lightweight sheet reduces transport cost and installation load.
- Smooth polyester paint provides clean color and decorative appeal.
- Good bending ability supports cutting, punching, folding, roll forming, and profiling.
- Aluminum substrate offers natural anti-rust performance.
- Coating system improves resistance to stains, moisture, and handling scratches.
- Wide color selection supports architectural, advertising, and industrial design.
- Cost-performance balance is favorable for large-area decorative projects.
Technical Specifications
| Parameter | Typical Range | Notes |
|---|---|---|
| Thickness | 0.20-3.00 mm | Other thicknesses can be discussed |
| Width | 600-1600 mm | Common widths include 1000, 1220, 1250, 1500 mm |
| Length | 1000-6000 mm | Cut-to-length sheet available |
| Coil inner diameter | 405 mm / 508 mm | For coil supply before sheet cutting |
| Top coating thickness | 15-25 μm | Higher thickness available for demanding use |
| Back coating thickness | 5-12 μm | Service coating or protective back paint |
| Primer thickness | 5-8 μm | Supports adhesion and corrosion resistance |
| Gloss | 10-90 GU | Matte to high gloss |
| Color tolerance | ΔE ≤ 1.5 | Based on agreed standard sample |
| Pencil hardness | HB-F | Depends on coating formula |
| T-bend | ≤ 2T | Typical for forming-grade material |
| Adhesion | Grade 0 | Cross-cut test, no peeling under normal condition |
| Salt spray resistance | 500-1000 h | Varies by alloy, pretreatment, coating thickness |
| Service temperature | -40°C to 80°C | Avoid continuous high-temperature exposure |
Aluminum Alloy and Temper Selection
Selecting the alloy and temper is important because the painted surface must survive fabrication without cracking. Soft tempers are better for deep forming and tight bending, while harder tempers provide higher flatness and strength.
| Alloy | Temper | Strength Level | Formability | Common Application |
|---|---|---|---|---|
| 1100 | H14, H24 | Low | Excellent | Ceiling, lighting, decoration, signs |
| 3003 | H14, H24 | Medium | Very good | Wall panels, roofing sheets, cabinet panels |
| 3004 | H24, H26 | Medium-high | Good | Roofing, exterior profiles, roll-formed panels |
| 3105 | H14, H24, H26 | Medium | Good | Painted building sheet, shutter, trailer panels |
| 5052 | H32, H34 | High | Moderate | Marine-adjacent panels, stronger decorative sheet |
Chemical Composition of Common Substrates
The values shown are typical maximum or range values used for reference. Final composition should follow ASTM, EN, JIS, or customer-agreed standards.
| Alloy | Si | Fe | Cu | Mn | Mg | Cr | Zn | Al |
|---|---|---|---|---|---|---|---|---|
| 1100 | Si+Fe ≤ 0.95 | Si+Fe ≤ 0.95 | 0.05-0.20 | ≤ 0.05 | - | - | ≤ 0.10 | ≥ 99.00 |
| 3003 | ≤ 0.60 | ≤ 0.70 | 0.05-0.20 | 1.00-1.50 | - | - | ≤ 0.10 | Balance |
| 3004 | ≤ 0.30 | ≤ 0.70 | ≤ 0.25 | 1.00-1.50 | 0.80-1.30 | - | ≤ 0.25 | Balance |
| 3105 | ≤ 0.60 | ≤ 0.70 | ≤ 0.30 | 0.30-0.80 | 0.20-0.80 | ≤ 0.20 | ≤ 0.40 | Balance |
| 5052 | ≤ 0.25 | ≤ 0.40 | ≤ 0.10 | ≤ 0.10 | 2.20-2.80 | 0.15-0.35 | ≤ 0.10 | Balance |
Coating Structure
A high-quality polyester coated aluminum sheet is not only paint on metal. It is a layered system where pretreatment, primer, topcoat, and backcoat work together.
| Layer | Function | Typical Thickness |
|---|---|---|
| Protective film | Prevents scratches during processing and installation | 30-80 μm, optional |
| Polyester topcoat | Provides color, gloss, stain resistance, and weathering protection | 15-25 μm |
| Primer | Improves bonding between aluminum and paint | 5-8 μm |
| Pretreatment film | Enhances corrosion resistance and coating adhesion | Chemical conversion layer |
| Aluminum substrate | Provides strength, light weight, and workability | 0.20-3.00 mm |
| Backcoat | Balances stress and protects the reverse side | 5-12 μm |
Applications
Polyester coated aluminum sheet is especially useful where color appearance, easy fabrication, and moderate environmental resistance are required.
| Application Area | Recommended Alloy | Suggested Thickness | Reason for Use |
|---|---|---|---|
| Ceiling panels | 1100, 3003 | 0.40-1.00 mm | Light, flat, easy to punch and install |
| Roofing sheet | 3003, 3004, 3105 | 0.50-1.20 mm | Good roll forming and weather protection |
| Wall cladding | 3003, 3105 | 0.70-2.00 mm | Stable color and clean facade appearance |
| Sign board | 1100, 3003 | 0.30-1.50 mm | Smooth surface for printing and lettering |
| ACP face sheet | 1100, 3003, 3105 | 0.12-0.50 mm | Flexible lamination and decorative color |
| Appliance panel | 3003, 5052 | 0.40-1.20 mm | Good surface quality and light forming |
| Garage door and shutter | 3105, 3004 | 0.60-1.20 mm | Strength, coating adhesion, and roll-forming ability |
Polyester Coating Compared with Other Finishes
| Finish Type | Cost | Weather Resistance | Formability | Recommended Use |
|---|---|---|---|---|
| Polyester coating | Economical | Good | Very good | Indoor decoration, signage, roofing, ceiling |
| High-durability polyester | Medium | Better | Good | Building panels with higher color retention demand |
| PVDF coating | Higher | Excellent | Good | Long-life exterior facade and harsh climate areas |
| Powder coating | Medium | Good | Limited after coating | Finished parts, profiles, fabricated components |
| Bare aluminum | Low | Natural aluminum resistance | Excellent | Industrial use without color requirement |
Polyester coating is a practical choice when the project needs rich color, fast processing, and balanced cost. For seaside, heavy industrial, or long-term high-UV projects, PVDF or high-durability polyester may be more suitable.
Fabrication and Handling Guidance
Use clean gloves and soft worktables to prevent surface scratches. When cutting or punching, keep tools sharp to reduce burrs. For bending, confirm the minimum bend radius by alloy, temper, thickness, and coating type before mass production. If protective film is used, remove it soon after installation, especially under sunlight, to avoid adhesive residue.
| Process | Recommendation |
|---|---|
| Cutting | Use sharp shearing, CNC cutting, or slitting tools |
| Bending | Test bend direction and radius before production |
| Roll forming | Maintain clean rollers and suitable forming speed |
| Drilling | Remove chips quickly to avoid coating abrasion |
| Cleaning | Use mild detergent and water, avoid strong alkali or abrasive pads |
| Storage | Keep dry, ventilated, and away from chemical vapor |
Quality Inspection
Reliable polyester coated aluminum sheet should be checked before shipment to confirm appearance, coating thickness, adhesion, mechanical behavior, and packaging condition.
| Inspection Item | Test Method | Acceptance Focus |
|---|---|---|
| Surface appearance | Visual inspection under proper light | No obvious scratches, dents, stains, color bands |
| Thickness | Micrometer or thickness gauge | Within agreed tolerance |
| Coating thickness | Eddy current gauge | Meets coating specification |
| Gloss | Gloss meter | Consistent with approved sample |
| Color difference | Colorimeter | Within ΔE requirement |
| Adhesion | Cross-cut or tape test | No peeling or flaking |
| Bending | T-bend test | No serious cracking at agreed bend level |
| Impact resistance | Impact tester | No coating separation after impact |
Packaging and Delivery
Sheets are usually packed with protective film, moisture-resistant paper, edge protection, wooden pallets, and steel or plastic straps. For export shipment, waterproof wrapping and seaworthy pallets help protect the coated surface during long-distance transport.
| Packaging Element | Purpose |
|---|---|
| Protective film | Reduces handling scratches |
| Interleaving paper | Prevents friction between sheets |
| Corner guard | Protects sheet edges during lifting |
| Wooden pallet | Supports flat stacking and forklift handling |
| Waterproof cover | Prevents moisture damage during storage and shipping |
Purchasing Notes
When ordering polyester coated aluminum sheet, confirm alloy, temper, thickness, width, length, coating thickness, color code, gloss, protective film requirement, and end-use environment. A small sample approval before bulk production helps ensure the color, gloss, and surface texture meet project expectations.
Polyester coated aluminum sheet is a versatile painted aluminum material for customers who need an attractive surface, dependable forming performance, and efficient project cost. With the right alloy, temper, coating thickness, and packaging, it delivers clean appearance and stable processing performance across decoration, construction, advertising, and light industrial applications.
