Influence of procedural noise on the glossiness of 2.5D printed patches

Perlin noise, a type of procedural noise, was used for the design of elevation files for 2.5D printing. This printing method uses elevation data from a height map to create physical relief by superimposing layers of ink. In this experiment, the grayscale values of noise functions were used as elevation values to build different surface structures in UV curable ink by 2.5D printing. Printed samples with varying levels of Perlin noise were created and their reflectance properties were studied by measuring the values of specular gloss. The roughness and specular gloss of the printed surfaces were effectively influenced when varying the persistence and octaves of the noise functions. The aim of implementing the procedural approach to a high-resolution printing method has been to explore the reflectance properties of custom noise functions when transferred to the physical realm. This might contribute to better understand the effect of surface structure on the appearance of materials. Potentially, this approach will enable the use of relief printing to produce structures with a more natural appearance and a desired gloss value by using a low-cost computing process.

Novel anti-ultraviolet performances of thin films polyurethane containing nano-mixed oxides CeO2-TiO2

The nano-mixed oxides CeO2-TiO2 was synthesized by gel combustion method using polyvinyl alcohol as fuel and mixtures of titanium trichloride and cerium(IV) nitrate at a relatively low calcination temperature of 550°C for 2 h. The prepared CeO2-TiO2 nanoparticles with a specific area of 65.70 m2 g−1 were dispersed in polyurethane matrix in different concentration conditions from 0.0 to 1.5 wt% to study ultraviolet durability following HONDA HES D 6501-97 standards. After 400 h of testing in the QUV accelerate weathering tester, the thin film containing 1 wt% CeO2-TiO2 nano-mixed oxides has presented the noticeable capacity for absorbing ultraviolet light by only 6.8 g.u change in specular gloss at 60° and ΔE = 3.66 in color difference.