Citric Acid–Peroxide Etchant for Small Studios
柠檬酸双氧水环保蚀刻液
标签：柠檬酸, 双氧水, 环保蚀刻, 入门配方
小批量铜件可用柠檬酸+双氧水替代三氯化铁：柠檬酸 150 g/L 加 30% 双氧水 100 mL/L，室温蚀 0.05 mm 铜箔约 15–25 min；蚀速随双氧水消耗下降，每 20 min 补加 10 mL/L 维持。优点是无铁盐染色、液体透明可视、废液加碱调 pH 至 7 后铜即沉淀回收，是最易合规的入门配方。注意双氧水避光冷藏、不可与金属粉末共储；深度超过 0.3 mm 的蚀刻或黄铜件仍建议用 FeCl3。
Small copper batches can skip ferric chloride: citric acid 150 g/L plus 30% hydrogen peroxide 100 mL/L etches 0.05 mm foil in 15–25 min at room temperature; rate falls as peroxide depletes, so top up 10 mL/L every 20 min. No iron staining, fully transparent bath, and spent solution neutralised to pH 7 drops copper out as sludge—the easiest-to-comply starter etchant. Store peroxide dark and cold, never near metal powders; for depths beyond 0.3 mm or brass work, return to FeCl3.