Engineering flexible superblack materials
Yucheng Yang, Botond Sánta, Ashok Ponnuchamy, Edward C. Kinzel, Anthony J. Hoffman, Matthew R. Rosenberger
Abstract
Flexible superblack materials are crucial for minimizing stray light, complicating object identification, and serving as low reflectance standards. However, the applications of existing superblack materials are limited due to challenges related to cost-effective scalable manufacturing, surface durability, and material conformability. Furthermore, existing fabrication platforms struggle to tailor superblack materials to application-specific needs. This work introduces an engineering platform that combines silicon mold fabrication and polymer casting to produce flexible superblack materials. This platform achieves repeatable wafer-scale production of superblack materials with a minimum reflectance of 0.15% and less than 0.4% across the visible spectrum. The sample reflectance is weakly dependent on illumination angles from 0° to 50° and observer angles from 0° to 70° when the illumination angle is less than 20°. This Lambertian-like reflectance profile enables the material to effectively conceal three-dimensional features in digital images even under intense lighting conditions. This platform can engineer the material surface to withstand tweezer scratches without significantly compromising its reflectance properties. This work introduces an engineering platform for designing flexible superblack materials, addressing key challenges in scalability, surface durability, mechanical flexibility, and customization.