(19e) Automated Langmuir-Blodgett Deposition of Particles on a Non-Flat Surface

The preparation of coatings with well-defined structures on a commercially viable scale has posed a significant engineering challenge, however recently, the use of directed assembly and self-assembly processes has been shown to be an excellent approach for creating scalable, uniform particle coatings. Specifically, the use of an automated Langmuir-Blodgett process has been shown to allow scale-up of the same well-defined nano/meso structured particle coatings produced through the likes of lab-scale convective deposition. However, existing work in this area has focused on the use of flat or near-flat substrates.

In this work, we demonstrate the deposition of sub-micron, monolayer particle coatings onto a lenticular substrate, with a repeating ~250 µm negative parabolic topography, through the use of a roll-to-roll automated Langmuir-Blodgett process. The influence of topographic gradient and substrate orientation relative to the drying front are explored through analysis of particle spacing. Additionally, the characterization of coatings as submonolayer or monolayer is also shown to be relative to the local substrate gradient. Understanding of this process opens up automated deposition to a wider range of materials and applications.