The main challenge in preparing a flexible mold stamp using roll-to-roll nanoimprint lithography is to simultaneously increase the imprintable area with a minimized perceptible seam. However, the current methods for stitching multiple small molds to fabricate large-area molds and functional surfaces typically rely on the alignment mark, which inevitably produces a clear alignment mark and stitched seam. In this study, we propose a mark-less alignment by the pattern itself method inspired by moiré technique, which uses the Fourier spectral analysis of moiré patterns formed by superposed identical patterns for alignment. This method is capable of fabricating scalable functional surfaces and imprint molds with quasi-seamless and alignment mark-free patterning. By harnessing the rotational invariance property in the Fourier transform, our approach is confirmed to be a simple and efficient method for extracting the rotational and translational offsets in overlapped periodic or nonperiodic patterns with a minimized stitched region, thereby allowing for the large-area and quasi-seamless fabrication of imprinting molds and functional surfaces, such as liquid-repellent film and micro-optical sheets, that surpass the conventional alignment and stitching limits and potentially expand their application in producing large-area metasurfaces.

Evaporation-induced particle aggregation in drying droplets is of significant importance in the prevention of pathogen transfer due to the possibility of indirect fomite transmission of the infectious virus particles. In this study, particle aggregation was directionally controlled using contact line dynamics (pinned or slipping) and geometrical gradients on microstructured surfaces by the systematic investigation of the evaporation process on sessile droplets and sprayed microdroplets laden with virus-simulant nanoparticles. Using this mechanism, we designed robust particle capture surfaces by significantly inhibiting the contact transfer of particles from fomite surfaces. For the proof-of-concept, interconnected hexagonal and inverted pyramidal microwall were fabricated using ultraviolet-based nanoimprint lithography, which is considered to be a promising scalable manufacturing process. We demonstrated the potentials of an engineered microcavity surface to limit the contact transfer of particle aggregates deposited with the evaporation of microdroplets by 93% for hexagonal microwall and by 96% for inverted pyramidal microwall. The particle capture potential of the interconnected microstructures was also investigated using biological particles, including adenoviruses and lung-derived extracellular vesicles. The findings indicate that the proposed microstructured surfaces can reduce the indirect fomite transmission of highly infectious agents, including norovirus, rotavirus, or SARS-CoV-2, via respiratory droplets.

This study proposes a comprehensive digital twin (DT)-based architecture for wire arc directed energy deposition (WA-DED) to address critical challenges in digital manufacturing, particularly focusing on interoperability, real-time process control, and defect monitoring. Built upon the ISO-23247 framework, the architecture integrates standardized approaches and advanced technologies to enable systematic anomaly detection and precise process management. Key components include flexible robot trajectory generation and path strategy modules, enhancing design flexibility and manufacturing efficiency. Bidirectional data flow is facilitated through an open-source platform using socket communication, ensuring seamless interoperability between industrial robots and various applications. Real-time anomaly detection and prediction are implemented using YOLOv10 and LabVIEW, enabling the identification of deposition defects through 2D data analysis and real-time prediction of contact tip to work distance (CTWD) using 1D data. These capabilities improve process monitoring and provide critical insights for quality control. Although full cloud integration is yet to be realized, future developments aim to establish continuous feedback loops through advanced cloud-based data storage and network systems. This will further enhance autonomous deposition processes by enabling dynamic responses to real-time changes in heat input, temperature, and deformation. The proposed DT-based WA-DED system represents a significant advancement in intelligent, cyber-physical manufacturing environments. It lays the foundation for enhanced process optimization, paving the way for future research and industrial applications in high-performance metal additive manufacturing.

Owing to their unique structural robustness, interconnected reentrant structures offer multifunctionality for various applications. a scalable multistep roll‐to‐roll printing method is proposed for fabricating reentrant microcavity surfaces, coined as wetting‐induced interconnected reentrant geometry (WING) process. The key to the proposed WING process is a highly reproducible reentrant structure formation controlled by the capillary action during contact between prefabricated microcavity structure and spray‐coated ultraviolet‐curable resins. It demonstrates the superior liquid repellency of the WING structures, which maintain large contact angles even with low‐surface‐tension liquids, and their robust capability to retain solid particles and liquids under external forces. In addition, the scalable and continuous fabrication approach addresses the limitations of existing methods, providing a cost‐effective and high‐throughput solution for creating multifunctional reentrant surfaces for anti‐icing, biofouling prevention, and particle capture.

The primary challenge in creating controllable liquid-based materials lies in managing the structural complexities and multiscale interfaces that govern solid, liquid, and gas phase interactions. Current fabrication methods for liquid-infused surfaces lack topological flexibility, limiting them to planar and simple-patterned structures. Conversely, digitally fabricating slippery architectural materials marks a significant shift towards scalable microprinting of complex, topologically slippery designs. This paper introduces a method for digitally fabricating slippery objects with solid–liquid composite interfaces and geometric design freedom. The slippery architecture has been demonstrated through digital printing of photopolymerization-induced multiphase materials and photoinduced grafting, enabling precise control over structural topologies and slippery properties of infused liquids. This versatile platform facilitates the fabrication of structures at multiple scales, enhancing liquid manipulation, droplet evaporation, and biomedical microfluidic chip design. These methods advance beyond conventional techniques, showcasing the potential of architected slippery surfaces with controlled structural scales.

Functional films with hydrophobic, oleophobic, anti-fouling, anti-icing, anti-bacterial and low reflectance properties can be produced by patterning nano- or micro-structures on films via nano imprint lithography. Here, an omni-phobic surface showing both hydrophobicity and oleophobicity was obtained without chemical surface treatment by increasing the surface roughness and deforming the pattern morphology using only nano imprint lithography and the oxygen-inhibited curing properties of polyurethane acrylate (PUA) resin. A tulip-shaped pattern imprinting process was designed in which microscale patterns were fabricated using a porous polydimethylsiloxane (PDMS) mold with high oxygen transmission. During ultraviolet (UV) curing, a curing inhibiting layer was formed by reaction with oxygen. Next, a PDMS pad was used for the pressurized curing of the curing inhibition layer to modify the micro scale structures. Finally, final curing of the deformed pattern was performed using ultra high-power UV light. The deformation of the pattern into tulip-like shapes with increased surface roughness was confirmed by microscopy, and contact angle measurement was performed to confirm omni-phobicity. The final cured imprinted samples showed water and oil contact angles reaching 169.2° and 115°, respectively; thus, the omni-phobic surface could be demonstrated by a tulip-shaped pattern imprinting process.