Face masks (respirators, protective and beauty masks) are 3D large-curve structures with air-tight lips. The mold focus is curve parting, air-tight lip molding and soft-hard composite.

Design Highlights

3D parting: parting follows the mask profile, and the sealing lip sits on a flat or shallow-angle surface to limit the flash effect on air-tightness;
Air-tight lip: thin-wall uniform lips (0.8~1.5 mm) with ring/multi-point gating for balanced flow;
Soft-hard composite: a rigid interface plus soft mask uses overmolding or two-shot: mold the rigid part first, then overmold the soft silicone;
Venting: vent inserts or vacuum venting at the nose bridge and chin corners;
Ejection: air plus flexible ejection for soft parts to protect the lip.

Process and Criteria

Mold temperature 170~200C, cure time per lip thickness. Use a negative-pressure holding test (air-tightness) and profile as outgoing criteria.

Common Defects

Air-tightness failure: uneven lip thickness or shrinkage;
Overmold delamination: bonding system and substrate contamination;
Bubbles or flow marks: insufficient venting and fill balance.

Delivery

Structure design, overmolding solution and trial validation of face mask molds, with assembly validation support.