2/1 Prepainted Color Steel Coil with 5–15μm Back Paint and 700–1250mm Width for Roofing and Panel Fabrication

1. Product Overview

Prepainted color steel coil is used in roofing sheets, wall panels, decorative cladding, and light fabricated components where both surface finish and coated substrate protection are required. Compared with unpainted metal sheet, the painted surface provides color consistency and a more stable visual finish for visible applications.

For this type of product, coating system, paint thickness, and forming properties are the main practical factors. A 2/1 paint structure is commonly used for standard construction and panel applications where one primer and one topcoat on the exposed side are sufficient for the project environment.

2. Technical Solution

Product performance is based on:

• Coated steel substrate providing the base protective layer
• Organic paint film acting as an additional barrier against weather exposure
• Different coating systems matched to different outdoor conditions
• Controlled top and back paint thickness for balanced appearance and service performance
• Mechanical properties suitable for bending, roll forming, and panel fabrication

For panel production, the back paint layer is not only a visual feature. A 5–15 μm back coat helps improve basic backside protection during storage, handling, and installation. At the same time, yield strength and elongation influence cracking risk during bending and edge forming.

3. Specifications

4. Application

• Roofing sheets and roof trims
• Wall cladding and facade panels
• Ceiling and decorative interior panels
• Garage doors and shutter panels
• Appliance housings and light industrial covers
• General construction sheet fabrication

5. Processing

• Cut-to-length sheet production
• Slitting into narrower strips
• Roll forming for roof and wall profiles
• Bending and folding
• Panel pressing and edge forming
• On-site installation after screw fixing or concealed fastening design

6. Advantages

• 2/1 coating structure is suitable for standard visible panel applications
• Back paint thickness of 5–15 μm supports backside coverage and handling protection
• 700–1250 mm width range fits mainstream panel and roll forming lines
• 0.11–1.2 mm thickness range covers light to medium gauge construction sheets
• Multiple coating systems allow selection by exposure level and project budget
• RAL color system supports project-based color matching

7. How to Choose

• General indoor or mild outdoor use → PE is commonly selected
• Projects requiring better weather resistance → SMP or HDP is often preferred
• Long-term exterior exposure or stronger UV resistance → PVDF is commonly considered
• Higher appearance requirement → choose top coating closer to 20–25 μm
• General building panel use → 2/1 structure is commonly sufficient, while more demanding systems may require 2/2 or above

8. FAQ

Q1: What does 2/1 coating structure mean?
It usually means one primer and one topcoat on the exposed side, with a standard backside coating for general panel applications.

Q2: Is 5–15 μm back paint thickness enough for construction panels?
It is commonly used for standard applications, but the required thickness should still match the service environment and project specification.

Q3: Which coating system is better for outdoor use?
PE is commonly used for standard outdoor projects, while SMP, HDP, and PVDF are generally selected when stronger weather resistance is required.

Q4: Can this coil be roll formed into roofing and wall sheets?
Yes, it is commonly used for roll forming, cut-to-length processing, and panel fabrication.

Q5: What coil size is suitable for standard processing equipment?
Coil IDs of 508 mm and 610 mm and coil weights of 3–8 MT are commonly used in industrial decoiling and roll forming lines.