- Customer: Hehuidegao
- Cooperation Model: ODM Customized Development
- Final Application: Mobile Phone Frame Repair Coating (Southeast Asia & Africa Markets)
- Product: Mirror Finish Silver Resin
1. Customer Background & Requirements
Hehuidegao specializes in mobile phone repair coatings, with products mainly supplied to Southeast Asia and African markets. These regions feature hot and humid climates, frequent smartphone usage, and high requirements for coating performance, including adhesion, metallic finish, abrasion resistance, and ease of application.
The customer required a coating solution for ABS + fiberglass mobile phone frames, with two key requirements:
- Excellent mirror silver metallic appearance
- The mirror effect must remain unchanged after PU topcoat application
Although the requirements appeared straightforward, the project involved complex formulation challenges. The coating system needed to achieve a highly reflective metallic finish on ABS + fiberglass substrates while maintaining brightness and gloss after PU coating.
Challenge: Compatibility Between Dual-Layer Coating System
The required chrome coating process:
Mirror Silver Primer (80℃ × 20 min) + PU Topcoat (80℃ × 30–40 min)
The 3 main technical challenges included:
1) Interlayer Adhesion
The mirror silver coating needed excellent adhesion while maintaining compatibility with the PU topcoat, avoiding poor bonding or coating defects caused by incompatibility between the two layers.
2) Mirror Effect Retention
The PU solvent system could potentially affect the silver layer, causing re-dissolution, haze, or loss of metallic brightness. The challenge was to maintain the original mirror gloss and metallic finish after topcoating.
3) Application Flexibility
Since the products are used in different overseas markets, the chrome coating system needed a wider application window and better tolerance under various environmental conditions.
Boya Customized Solution
| Dimension | Customer Requirement | Boya Chemical Solution |
| Mirror Finish Effect | Strong metallic finish | Developed a highly oriented resin system to improve aluminum flake alignment and achieve rich metallic gloss |
| PU Compatibility | No haze, no gloss reduction after topcoat | Optimized primer crosslinking and matched the PU solvent system to maintain high gloss and clarity |
| ABS + Fiberglass Adhesion | Strong substrate adhesion | Combined adhesion promoter technology with customized resin formulation; passed cross-cut adhesion testing |
| Process Compatibility | Low-temperature curing at 80℃ | Fully matched customer’s existing repair coating process without equipment modification |
| Application Reliability | Adaptable to overseas environments | Optimized formulation for high humidity conditions to reduce whitening and uneven appearance risks |
Application Scenarios
The developed chrome coating system is mainly used for:
- Mobile phone frame scratch repair: Restoring metallic finish after daily wear and damage
- Housing refurbishment: Recovering the original mirror finish of used devices
- Southeast Asia & Africa markets: Providing stable coating performance under hot and humid conditions with reduced risks of whitening and peeling
Project Progress
The project has entered the sample validation stage. The customer has recognized the mirror finish performance and gloss retention after PU topcoating. The project is expected to proceed to small-batch production after final confirmation.
For repair coating applications, achieving the required mirror finish silver primer + PU topcoat dual-layer performance in the first sample trial demonstrates the effectiveness of Boya Chemical’s formulation capability and process matching expertise, helping customers accelerate product launch in overseas markets.
If you are looking for mirror finish silver resin solutions for ABS, ABS+PC, PC, or other plastic substrates, please feel free to contact Boya Chemical for customized development support.
