Premium acetate frames require pharmaceutical-grade cellulose acetate and multi-stage craftsmanship:
1. Acetate Sheet Production
Raw plant-based cellulose is dissolved in acetone with organic pigments.
Liquid compound is roller-coated onto acetate sheets.
Multicolored layers are fused under hydraulic pressure or extruded through dies.
Sheets are chopped into cubes, re-compressed into blocks, and kiln-dried for 6-8 weeks.
2. Component Fabrication
CNC mills cut frame parts to 0.1mm precision.
Technicians heat acetate to 85°C for:
Front frame curvature forming using metal templates
Inserting titanium core wires and hinges
Nose pads are bonded with epoxy adhesives.
3. Surface Polishing
Parts undergo 72-hour tumbling in rotary drums with:
Walnut shell granules (primary abrasion)
Pumice stones (final smoothing)
Manual buffing with rotating wheels achieves optical-grade finish.
4. Final Assembly
Temples are attached with titanium screws (0.3Nm torque).
Lenses are mounted with <0.5° tilt tolerance.
Frames undergo ultrasonic cleaning.
*Process Note: Each stage requires specialized technicians. Hand-finishing accounts for 60% of production time.*