Stereolithography enables the fabrication of three-dimensional (3D) freeform structures via light-induced polymerization. However, the accumulation of ultraviolet dose within resin trapped in negative spaces, such as microfluidic channels or voids, can result in the unintended closing, referred to as overcuring, of these negative spaces. We report the use of injection continuous liquid interface production to continuously displace resin at risk of overcuring in negative spaces created in previous layers with fresh resin to mitigate the loss of Z-axis resolution. We demonstrate the ability to resolve 50-μm microchannels, breaking the historical relationship between resin properties and negative space resolution. With this approach, we fabricated proof-of-concept 3D free-form microfluidic devices with improved design freedom over device material selection and resulting properties.

中文翻译：

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高分辨率立体光刻：通过流体力学控制实现负空间


立体光刻技术能够通过光诱导聚合制造三维 (3D) 自由形状结构。然而，被困在负空间（例如微流体通道或空隙）中的树脂内紫外线剂量的积累可能会导致这些负空间的意外关闭，称为过度固化。我们报告使用注射连续液体界面生产来连续置换前一层中用新鲜树脂产生的负空间中存在过度固化风险的树脂，以减轻 Z 轴分辨率的损失。我们展示了解析 50 μm 微通道的能力，打破了树脂特性与负空间分辨率之间的历史关系。通过这种方法，我们制造了概念验证的 3D 自由形状微流体设备，在设备材料选择和最终性能方面提高了设计自由度。