The scales of white beetles strongly scatter light within a thin disordered network of chitin filaments. There is no comparable artificial material achieving such a high scattering strength within a thin layer of low refractive index material. Several analyses investigated the scattering but could not explain the underlying concept. Here a model system is described, which has the same optical properties as the white beetles’ scales in the visible wavelength range. With some modification, it also explains the behavior of the structures in the near infrared range. The comparison of the original structure and the model system is done by finite-difference time-domain calculations. The calculations show excellent agreement with the beetles’ scales with respect to the reflectance, the time-of-flight, and the intensity distribution in the far-field.

Novel bifunctional cellulose diacetate derivatives were synthesized in order to achieve bio-based photoresists, which can be structured by two-photon absorption via direct laser writing (DLW) without the need to use a photoinitiator. Therefore, cellulose diacetate is functionalized with thiol moieties and olefinic or methacrylic side groups enabling thiol-conjugated cross-linking. These cellulose derivatives are also photo-cross-linkable via UV irradiation (λ=254nm and 365 nm) without using an initiator.

The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adem.202201688.

The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adom.202200700.