We have developed novel high hardness and anti-fouling UV-curable resin for nano-scale patterning purpose. Moth-eye structure films were transferred by nanoimprint lithography using moth-eye structured mold. As a result, transferred moth-eye structure was 0.3% reflectivity at visible light wavelength and endured steel wool scratch test. In addition, before and after scratch test, contact angles of water of moth-eye structured films were over 150°, which means superhydrophobic. Anti-fouling test using artificial finger print liquid was also examined. After 100 times wipe-out, no stain was observed on transferred moth-eye structure film and reflectivity kept low value.

We found that titanate nanosheets (<1%), in water, form a periodic structure to exhibit a vivid structural color. The resultant nanostructure is similar to that in iridophores of tropical fish, such as neon tetra and blue damselfish, where they can control their structural colors on their surfaces. Owing to its high structural integrity and fluidity, the aqueous dispersion of nanosheets can quickly change its structural color in response to external stimuli, such as temperature, pH and a magnetic field. Furthermore, a photonic hydrogel, which is fabricated by polymerizing the above photonic structure of the nanosheets, can reversibly change its structural color in response to the applied pressure.

Mazda has developed sophisticated colors by pursuing contrast expression to emphasize beauty of Kodo-design, under philosophy of “color is part of design”, and introduced Soul Red Premium Metallic™ and Machine Gray Premium Metallic™ into global market. Sophisticated color is typically composed of multiple film layers for coloring and texture, so paint usage and process are increased, and affects environmental/economic performance. Mazda has established environmental-friendly paint process, and by applying those technologies, sophisticated colors could be developed without increasing film layers. In this report, we would like to introduce development of Soul Red Crystal Metallic™ that emphasizes Kodo-design-evolution.

Recently, development of coloured pigments with minimal environmental impact attracts much attention. Structural colour of colloidal arrays is one of the most versatile candidates because the colour can be tuned by choosing the size of particles. Electrophoretic deposition (EPD) can be applied to prepare particles arrays. Recently, we have successfully prepared colourful coatings consisting of SiO₂ particles via the EPD method. Vivid coloured coatings on materials with curved surfaces and complicated shapes were successfully prepared. The iridescence, i.e., the angular dependence, of the structural colour could also be controlled by EPD conditions. In addition, robust structurally coloured coatings with high abrasion resistance were prepared by the cathodic EPD method using Mg²⁺ ions.

Photoluminescent quantum dots have attracted much attention due to potential applicabilities in various areas. However, research on the gas sensing properties of quantum dots is still in its infancy. We found that the CdSe-based core-shell quantum dots showed reversible changes in photoluminescence intensity in the presence of ppm levels of ozone in air. Furthermore, the ozone-sensitivity and response/recovery rate of the quantum dots were enhanced by the addition of Au or Pt nanoparticles. These results demonstrated that photoluminescent quantum dots have potential for use as optical ozone sensor, and that the sensing performance can be improved by noble metal nanoparticles.

In the case of chemical coloring of stainless steel, it has been pointed out that the color tone after coloring varies depending on the material lot of stainless steel. In addition, even with the same material, there are problems such as color difference depending on the surface condition, and the cause investigation and measures have been necessary. So, in this research, the processing solution composition etc. was improved and examination of the reduction method of color tone variation was carried out.