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Composites using a resin-impregnated grid layer and a thermocompression-bonded PET nonwoven fabric are being developed as an alternative material for under-cover of vehicles. This material is lightweight and low-cost, and has excellent sound absorption performance and durability. In this study, the tensile properties and Poisson’s ratio of thermocompression-bonded PET nonwoven fabrics prepared by needle-punching were measured. The specimen was formed by thermocompression bonding using hot press. Stress-strain curves of the 2 mm-thick specimens were calculated using a tensile tester and digital image correlation (DIC). The specimen thickness increased with increasing displacement along the tensile load direction in the thermocompression-bonded PET nonwoven fabrics prepared by needle-punching. This phenomenon started at the plastic region in the MD specimen and at the elastic region in the TD specimen. The Poisson’s ratio in each plane was also calculated. Thus, the basic properties required to simulate the mechanical behavior of the thermocompression-bonded PET nonwoven fabrics prepared by needle-punching were evaluated.

Fast-decaying phosphors are essential for a 3D plasma display panel (PDP) with high image quality. However, conventional green and red PDP phosphors have slow-decaying characteristics. We present the luminescence properties of new phosphors for 3D PDP application. Decay times of Y 3 Al 5 O 12 :Ce 3+ , (Y,Gd)Al 3 (BO 3 ) 4 :Tb 3+ , and (Y,Gd) 2 O 3 :Eu 3+ were significantly shorter than those of conventional PDP phosphors. CIE chromaticity coordinates and luminescence efficiencies of the phosphors were also suitable for PDP application. The development of fast-decaying PDP phosphors has enabled commercialization of 3D/2D switchable PDP television for the first time in PDP industry.

A H 3 BO 3 or B 2 O 3 flux was added to a mixture of BaS, EuS, Al, and S to synthesize a Eu-doped cubic BaAl 2 S 4 phosphor. The formation temperature of the cubic BaAl 2 S 4 phase was lowered to 600°C, which was 60°C below the temperature of a case without a flux. To improve the crystallinity and color purity, a two-step annealing process that involved low temperature annealing (130°C for H 3 BO 3 and 400°C for B 2 O 3 ) was proposed for a uniform immersion of a flux into a starting mixture and a high temperature annealing (600°C) for the formation of BaAl 2 S 4 . The phosphor synthesized by the two-step process with a 2 wt % H 3 BO 3 flux showed a distinct cubic BaAl 2 S 4 phase and a strong photoluminescence (PL) intensity at 475 nm. The PL intensity was 6.6 times stronger than that of the phosphor without a flux. The phosphor synthesized with a B 2 O 3 flux showed only an orthorhombic phase, while direct annealing at 600° with the flux showed a mixture of cubic and orthorhombic phases. The role of the fluxes in the formation mechanism of the cubic and orthorhombic BaAl 2 S 4 phases was described.

A Eu-doped BaAl 2 S 4 phosphor was synthesized by a liquid-phase reaction using BaS, EuS, Al, and S, where Al acts as a liquid source during the reaction, instead of Al 2 S 3 . The synthetic temperature of the cubic BaAl 2 S 4 phase could be reduced to as low as 660°C, considerably lower than that required for a phosphor synthesized via a solid-state reaction using BaS, EuS, and Al 2 S 3 . The cubic BaAl 2 S 4 :Eu phosphor synthesized using the liquid phase showed larger grains and higher crystallinity. The photoluminescence of the cubic BaAl 2 S 4 :Eu phosphor showed a blue emission centered at 470 nm with a CIE color coordinate at x = 0.12, y = 0.11. In addition to well-defined blue color, the PL intensity was doubled relative to the solid-state reaction case.

Eu-doped SnO 2 thin films deposited by radio-frequency (rf) magnetron sputtering have been studied for the transparent conductive phosphor layer, which is transparent in visible light, electrically conductive, and luminescent. The resistivity of the SnO 2 film increased as the firing temperature and Eu concentration increased. The film showed an excitation peak at 300 nm and an emission peak at 588 nm. The maximum photoluminescence and cathodoluminescence intensity was observed under conditions of 1.0 atom % Eu doping and a 1200°C firing temperature; the resistivity was 0.5 Ω cm and the transmittance was above 70%. The relation between the resistivity and cathodoluminescence intensity has been discussed.

A simple fabrication method of 2D SiO 2 corrugated layers and their suitability to enhance output coupling efficiency of a ZnS:Tb thin-film phosphor layer in an anode part of field emission display (FED) devices is discussed. For patterning of 2D dotted arrays of SiO 2 films, we used two-step irradiated hologram lithography and reactive ion etching. The formation of a wavelength-scale uniform 2D SiO 2 dotted array was confirmed by morphological analysis. We presented the finite-difference time-domain analysis for calculating the output light resulting from the insertion of a 2D SiO 2 corrugated layer into the interface between the glass substrate and the ZnS:Tb thin-film phosphor. A significant enhancement (a factor of 4.0-4.7) of the output coupling cathodoluminescence (CL) efficiency is reported in the low-voltage (0.5-4.5 kV) characteristics under electron-beam excitation for the ZnS:Tb thin-film phosphor deposited on a 2D SiO 2 corrugated substrate. The computational analysis, CL characterizations, and far-field measurement demonstrated that the 2D SiO 2 corrugated substrate served as diffraction scattering layers, increasing the output coupling efficiency, which is critically important for development of commercial FEDs employing thin-film phosphors.