移動式感應加熱應用於熱滾壓平板微結構的應用

The Application of Moving Induction Heating in Roll-to-Plate Embossing for Microstructure Replication

何峻瑋(Jyun-Wei He)

指導教授 ： 楊申語

國立臺灣大學/工學院/機械工程學研究所/碩士(2019年)

https://doi.org/10.6342/NTU201902226

摘要

微熱壓成型技術為複製高分子微結構元件之重要技術，具有製程簡單、成本低廉與高結構複製率等優勢。在傳統熱壓成型技術上，壓印方式為板對板的機構，易受摩擦力、壓板表面及平行度影響，有壓力分佈不均且壓印面積受限等缺點，加上熱壓機的壓板加熱與冷卻需整塊熱盤進行升、降溫動作，導致成型週期過長且耗費能源。
本研究使用滾輪對移動式平台進行施壓，擴大壓印面積與壓力均勻性，且使用感應加熱技術進行快速升溫，並搭配自主設計的真空吸附水冷平台進行快速降溫，之後將裝置與Arduino做結合，製作出自動化移動式感應加熱結合水路冷卻微結構壓印設備。
在壓印實驗上，我們以相同的進給速率164 mm/min，藉由調整功率和擺放磁場集中器的方式，提升模具整體的溫度均勻性，將鎳模具的最大溫差控制在22℃ 內。且為避免基材在壓印時有翹曲情況發生，本實驗開發真空吸附水冷平台，利用矽膠板將基材與模具吸附在平之上，解決成品變形問題。而在腔體設計上我們導入水冷系統，於腔體側面設計水路進行水冷降溫，解決降溫耗時問題。最後，自動化設備的導入，不僅可減少手動壓印時的操作誤差，也可更精確的掌握高週波的開關與壓印時間，確保每張微結構薄膜產品的品質與穩定性。
在實際應用上，本設備能複製V型溝槽與微透鏡陣列結構於PC基材上，其微結構面積可達100×100 mm2，轉寫率可超過95%以上，並藉由成型視窗的建立，證明自動化移動式感應加熱結合水路冷卻微結構壓印設備可應用於高分子光學元件之製備與可行性。

關鍵字

熱壓印成型 ； 移動式感應加熱 ； 滾對板施壓 ； 微結構複製

並列摘要

Traditional hot embossing is a popular technology for fabrication of polymer micro-structured components. It has the advantages of simple steps, high replication rate, and low cost. However, the traditional hot embossing employs plate-to-plate contact, inducing uneven pressure distribution. Moreover, it requires heating and cooling a whole hot plate which causes long cycle time and high energy cost.
In this study, we used a roller to imprint the microstructure, combined with the mobile platform to increase embossed area and pressure uniformity. In order to prevent a film warpage from heat/cool effects, the induction heating facility and a platform with vacuum and water cooling were employed. To improve the temperature uniformity, the ferrite were placed in the induction coil as a field concentrator. The maximum temperature difference is less than 22 °C. Programming control has been used facilitate automated mobile induction heating imprinting equipment, reducing the human operational errors during the embossing process.
The V-cut and microlens array microstructures were replicated on the 100×100 mm2 PC substrate. The replication rate can exceed 95%. The operation window was investigated. This study proves that the facility integrating induction heating and platform with vacuum and water cooling can be applied to the fabrication of polymer optical components with microstructure.

並列關鍵字

Hot embossing ； Induction heating ； Roll-to-plate (R2P) ； Microstructure

參考文獻

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