We are developing Quantum Dot (QD) inkjet ink for display with QD Color Conversion (QDCC) layer which is promising for next generation display. We have developed prototype of both thermal curing ink including solvent and UV curing ink excluding solvent. Then, we compared optical properties and ink jetting properties. Furthermore, we fabricated QDCC layer by inkjet deposition on glass substrate with bank. Thermal curing ink brought better color conversion efficiency at the same QDCC layer thickness as UV curing ink, but we found that UV curing ink brought better QDCC layer productivity and better surface flatness. Finally, we found that color gamut of QDCC layer by inkjet deposition with UV curing ink was as wide as that of commercial OLED TV.

In textile field, digital printing has rapidly expanded its presence because digital printing enables us to solve problems of traditional printing process. Furthermore, various core technologies such as inkjet printheads and inks have been continuously developed to realize high productivity with high printing quality. As a result, not only luxury brand but also fast fashion industry has used digital textile printer as a production machine. However, digital printing process is only one step among other several processes. If other processes aren't carried out appropriately, high printing quality never realizes. Thus, in this study, pre-treatment process which is specific process in digital printing is focused and the importance of pre-treatment process is discussed.

We focused on a nano-ink application method using high quality transparent conductive oxide (TCO) nanoparticles (NPs) to produce TCO thin films. The TCO NPs were synthesized by a liquid phase method which can be expected to yield TCO NPs with low resistivity. As the TCO NPs, we have prepared tin-doped indium oxide, gallium-doped zinc oxide, and antimony-doped tin oxide NPs. TCO NPs exhibited lower resistivity than the corresponding TCO prepared by conventional methods. The TCO thin films prepared by using the TCO-based nano-inks showed high transparency in the visible light region.

Looking back at the history of inkjet colorants, in the early days conventional dyes were used for which it was necessary to develop special inkjet paper.

In the growth period, new dyes and pigment dispersions have been developed in response to problems associated with plain paper and newly developed inkjet photographic paper.

Nowadays, in order to be able to adapt to various media, the combination of resin addition and colorant is used to improve the function.

Inkjet technology will surely continue to play an important role in the digital industrial revolution. Therefore it is important to provide colorants that meet the requirements of applications in various fields.

The removal mechanism of a photoresist film coated on an ITO substrate was studied by means of quartz crystal microbalance with dissipation monitoring (QCM-D) technique. The removal agent used in this study was a mixture of ethylene carbonate (EC) and propylene carbonate (PC). The QCM-D measurements demonstrated that the photoresist film was completely removed as a result of rinsing by the mixed solvent. Interestingly, the addition of water into the mixed solvent resulted in the swelling of the photoresist film. However, the removal efficiency decreased significantly at high water concentrations because the mixed solvent with water became a poor solvent for the photoresist. The addition of a Pluronic surfactant (F-68) into the mixed solvent resulted in an increase in the removal efficiency at a water concentration = 50 wt%. The polymeric surfactant induces the swelling of the photoresist film as well as the dispersion of the photoresist in the mixed solvent.