Why plasma cleaning when liquid silicone is encapsulated

Why Plasma Cleaning When Liquid Silicone is Encapsulated?

Plasma cleaning is a critical surface treatment step before liquid silicone encapsulation (over-molding). The main reasons include:

1. Surface Activation

Plasma treatment introduces reactive functional groups (OH, COOH, etc.) onto the substrate surface, significantly improving the chemical bonding between liquid silicone and the substrate material.

2. Contamination Removal

Plasma effectively removes organic contaminants, oils, and mold release agents from the substrate surface that could otherwise prevent proper adhesion.

3. Improved Wettability

Plasma treatment reduces the contact angle of the substrate surface, allowing liquid silicone to spread more evenly and achieve better interfacial contact.

Without proper plasma treatment, the adhesion between liquid silicone and substrates like plastics or metals may be insufficient, leading to delamination or seal failure.