現今在3C產品外表塗佈色彩文字及圖樣的方式，以模內成色及印刷技術為主要的兩個方法，但此兩種技術需考量到開模或製版之成本，故適合較大規模量產之產品。本研究開發之方法，只需將工作物件以軟體建模，配合欲噴印圖案的資料，經由程式轉換後即能立刻進行噴印路徑規劃，前置作業可完全在電腦上進行。噴印機台則是以五軸工具機為基礎，使用印表機軟體進行噴印。另外，由於噴墨頭與曲面距離並不固定，需盡量保持噴墨頭與被噴印面之距離在最佳噴印距離的範圍內，且噴墨頭一次能噴印的圖案寬度有限，若曲面曲率太大則必須旋轉一角度後再進行噴印，故此噴印寬度需與曲面曲率配合，以決定圖案該怎麼噴印；而五軸工具機的刀具及工件部份則分別以噴墨頭及曲面模型置換，故需另外設計夾持機構來固定噴墨頭與曲面模型。此外，如何使噴印訊號與五軸同步作動也是一項重點。綜合以上諸多要點，希望能藉此達到在3D曲面上噴印彩色圖案之目標。

There are two main methods to attach the colorful patterns to the free form surface of 3C products at present time, one is IMD and the other is screen-printing. Because of the cost on molding and plate-making, both methods are only suitable for the mass production. In this study, software is firstly used to do 3D modeling, after that the pattern is applied on the 3D model and then plans the printing paths by using mapping transformation. The pre-process of the printing can be finished on computer. The hardware is based on the 5-axis CNC machine; the spindle of the 5-axis CNC machine is replaced by a commercial printer and uses the software of the printer to print the pattern. Furthermore, since the distance between the print head and curved surface is not a constant, it is necessary to maintain the distance in an optimal range. The width of pattern print head can print at a time is limited by the curvature of the printing surface. If the curvature of surface is too big, the print head should print only at the region which can print out a good printing quality. The rest unprinted area is printed after rotating the print head a proper angle. Since print head and surface model are substitute for the tool and work piece, so it is necessary to design the fixture to fix the print head and curved surface model. Moreover, how to synchronize the print signal and 5-axis machine is also important. As mentioned above, this study hopes to achieve printing colorful patterns on the 3D free form surface.

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