溶劑鑄膜是製作光學薄膜重要之技術，但以流體力學探討溶劑鑄膜研究很少，本研究就是以流體力學觀點，探討牛頓流體對於溶劑鑄膜之影響。使用的牛頓流體包含黏度110 mPa•s~1900 mPa•s之甘油，與黏度120 mPa•s~10500 mPa•s之玉米糖漿。研究結果發現，起始塗佈速度差異會造成不同的塗佈結果，適當的起始速度可擴大塗佈視窗，避免unstable pooling的產生。黏度對於溶劑鑄膜影響與之前預調式塗佈有所不同，尤其是塗佈缺陷的改變，對於最大塗佈速度有明顯影響，如在塗佈間隙200-400μm時，最大塗佈速度與黏度變化可分為三個區域，在低黏度時為Region 1，最大塗佈速度隨著黏度增加而下降，Vmax時塗佈缺陷為unstable pooling；在黏度250 -600 mPa•s之間是過渡區域之Region 2，塗佈缺陷從unstable pooling變化成air entrainment，Vmax隨黏度增加而增加；高黏度時則為Region 3，塗佈缺陷維持空氣滲入，因此Vmax也隨黏度增加而下降。另外在Region 2與3中且黏度於295 mPa•s-1200 mPa•s之間，由於低塗佈間隙200μm時塗液打出瞬間液珠上游會被推往模具斜面，造成unstable pooling產生，造成塗佈間隙400μm之塗佈液珠較穩定，因此Vmax高於塗佈間隙200μm。 

An experimental study was carried out to investigate the solution casting process. Two viscous Newtonian liquids, aqueous glycerol solutions(viscosity between 110mPa.s and 1900mPa.s) and corn syrup(viscosity between 120mPa.s and 10500mPa.s) were used as test fluids and coated on dry PET film for observation. Several interesting defects were identified, such as vibrating edges and unstable pools in the neighborhood of the die lip region. The operating windows were studied as function of fluid viscosity、coating gaps, and different die lips.

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