本研究主要探討於液相中以化學還原方式搭配田口式優化試驗法進行實驗設計，並針對不同還原劑種類（因子 A）、反應溫度（因子 B）、還原劑劑量（因子 C）與反應器轉速（因子D）等參數，針對銅粉生成之轉換率、粒徑大小、反應時間所產生之影響進行探討，其中還原劑種類與反應溫度於本研究之反應體系中乃是相對影響最顯著之因子。本研究最終所得到之最佳操作參數為以次亞磷酸鈉作為還原劑、反應溫度控制在 70°C、還原劑添加量 8.14 kg、反應器轉速300 RPM；將合成之微細銅粉經由感應偶合電漿發射光譜儀（ICP-OES）、雷射粒徑分析儀（DLS）、掃描式電子顯微鏡（SEM）與X射線晶體分析儀（XRD）等儀器分析後，證明可得到一具有面心立方（face-centered cubic, FCC）純銅粉結構、不純物含量低於 0.06%、D50粒徑為1.51 μm之高純度微細銅粉，此法不僅沒有添加任何表面活性劑，且製程簡易適合工廠規模大量生產。

The Taguchi robust design method was used to optimize the experimental conditions for the synthesis of ultrafine copper powder via a chemical reduction method. The reducing agents, reaction temperatures, weight-reducing agents, and stirring rates were chosen as the primary factors, while the conversion rates, particle sizes, and reaction times were selected as the desired targets. The results indicate that the reducing agent and the reaction temperature were comparatively the significant
factors affecting the desired targets. The optimum conditions were as follows: factor A (reducing agent) at level 2 (NaH2PO2•H2O), factor B (temperature) at level 3 (70°C), factor C (weight-reducing agent) at level 3 (8.14 kg), and factor D (stirring rate) at level 2 (300 RPM). The results of the experimental confirmations for the three desired targets were matched with the predictions of the Taguchi method. Additionally, via an inductively coupled plasma emission spectrometer (ICP-OES), laser particle size analyzer (DLS), scanning electron microscopy (SEM), and X-ray diffraction (XRD) analyses, the pure (impurity <0.06 %) face-centered cubic structure with 1.51 μm medium size of the HUCP1 was characterized and determined. Finally, a surfactant-free facility and a method suitable for mass production were established to synthesize high-purity ultrafine copper powder.