Antique Brass (AB) & Antique Copper (AC): Chemical Aging & Clear Lacquer Sealing
Engineering Overview: Process breakdown of Antique Brass (AB) and Antique Copper (AC) finishes on solid brass cylinders, detailing chemical conversion and lacquer baking.
Technical & Engineering Specifications
| Process | Chemical Sulfide Patina + Relief Buff + Baked Lacquer |
|---|---|
| Substrate | Solid H59/H62 Extruded Brass |
| Application | Heritage Commercial & Luxury Hospitality |
| Finish Types | Antique Brass (AB), Antique Copper (AC) |
| Corrosion Benchmark | ASTM B117 96h Neutral Salt Spray |
Chemical Patina Process
Antique Brass (AB) and Antique Copper (AC) finishes provide vintage architectural aesthetics across solid extruded brass lock cylinders.
Production Protocol
- Chemical Conversion: The brass core is immersed in polysulfide or copper nitrate solutions, creating a deep uniform black/brown surface sulfide layer.
- Relief Buffing: Precision Scotch-Brite wheel buffing selectively relieves high-edges, exposing bright underlying golden brass or red copper highlights.
- Electrostatic Lacquer: Baked at 160°C with clear thermosetting acrylic lacquer, delivering ASTM B117 salt spray resistance of 96+ hours.
Frequently Asked Engineering & Selection Questions
Q1: Are Antique Brass finishes protected against tarnish?
Yes. After manual relief buffing, a baked clear thermosetting acrylic lacquer seals the patina against atmospheric oxidation.