Surface treatment, such as corona, plasma, or primer coating, boosts PI tape’s adhesive stability, ensuring strong, lasting bonds in high-heat, high-humidity, and high-stress environments.
Polyimide (PI) tape is widely used in electronics, aerospace, and industrial applications due to its high temperature resistance, excellent insulation, and chemical durability. However, beyond the base film’s quality, one critical factor that determines performance is adhesive stability—and this is heavily influenced by the surface treatment process applied to the PI film before coating.
1) Why Surface Treatment Matters
Raw polyimide film is chemically inert and has a smooth, low-energy surface, making it difficult for adhesives to bond directly. Without proper surface preparation:
Adhesive may peel or bubble under heat.
Long-term adhesion in high-humidity or high-temperature environments will degrade.
Mechanical stress can cause delamination.
2) Common Surface Treatment Methods
| Method | Mechanism | Effect on Adhesion | Remarks |
|---|
| Corona Discharge | Creates micro-oxidation and polar functional groups | Improves wettability and adhesive penetration | Cost-effective, widely used |
| Plasma Treatment | Uses ionized gas to activate surface chemically | Excellent adhesion improvement | Suitable for precision electronics |
| Chemical Etching | Alters surface chemically using strong reagents | High bonding strength | Must control process to avoid damaging film |
| Primer Coating | Applies a thin adhesive-friendly layer | Creates consistent bonding base | Adds an extra production step |
3) Impact on Adhesive Stability
Initial Tack: Proper treatment increases surface energy, allowing adhesive to wet and grip better.
Thermal Endurance: Treated surfaces prevent adhesive flow or creep under prolonged high-temperature exposure.
Moisture Resistance: Stronger bonds resist hydrolysis and delamination in humid environments.
Aging Stability: Reduces adhesive degradation over time, maintaining peel strength.
4) Best Practices for B-End Users
Specify treatment type and parameters when ordering PI tape for demanding environments.
For high-temperature masking (e.g., soldering, powder coating), plasma or primer treatments are recommended.
For flexible electronics or FPC manufacturing, low-damage plasma treatment ensures stable adhesion without affecting flexibility.
Always verify peel strength data from suppliers under target temperature/humidity conditions.
Conclusion
The surface treatment process of PI tape is a decisive factor in achieving stable, long-term adhesion. Whether the tape is used in electronics assembly, aerospace shielding, or industrial coating, the right treatment ensures performance stability even under extreme conditions.
