The effects of excimer light irradiation on polysilazane coatings formed on PET films with vacuum-evaporated SiO2 coatings and the effects of these coatings on gas barrier characteristics have been investigated. The t...The effects of excimer light irradiation on polysilazane coatings formed on PET films with vacuum-evaporated SiO2 coatings and the effects of these coatings on gas barrier characteristics have been investigated. The temperature during light irradiation has a large effect on the coating’s molecular structure and gas barrier characteristics. When irradiation was performed at 100℃, the polysilazane coating transformed into a silica coating, and a compact silica coating at a much lower temperature than with heat treatment alone was produced. Surface irregularities in the vapor-deposited silica coating were smoothed out by the formation of a polysilazane coating, which was transformed into a compact silica coating when irradiated with light, resulting in a significant improvement in the gas barrier characteristics. The water vapor permeability of the thin coating irradiated with excimer light at 100℃ showed only 0.04 g/m2•day (40℃, 90% RH). According to the results of investigation of temperature variation of water-vapor permeability, it is inferred that the developed film has an excellent gas barrier value, namely, 4.90 × 10–4 g/m2•day at 25℃. This gas barrier coated PET film is transparent and flexible, and can be used in the fabrication of flexible electronics. Also, the proposed fabrication method effectively provides a simple low-cost and low-temperature fabrication technique without the need for high vacuum facility.展开更多
Recently, the industry and productions have been rapidly developed by the advancement of science and technology. On the other hand, the dwindling natural resources and the global warming increasingly pose a severe pro...Recently, the industry and productions have been rapidly developed by the advancement of science and technology. On the other hand, the dwindling natural resources and the global warming increasingly pose a severe problem to our life in near future. Indeed, solar photovoltaic (PV) has been attractive as one of the alternative energy resource to oil. However, some problems such as the reduction of electromotive force and the degradation of back-sheet influence the properties of the long-term life of the PV panel system. In this research, we used the high- and low-molecular-weight PET film in order to evaluate the effect of molecular weight for the hydrolysis of PET under the acceleration degradation test. As results, the mechanical properties of PET film were decreased with increasing the acceleration degradation time. In addition, it was found that the dielectric breakdown strength of PET film indicated the similar tendency with the mechanical properties. Accordingly, the non-destructive analytical technique, i.e. the partial discharge measurement makes it easy to evaluate the degradation of PET film without any damage or cut out for the film.展开更多
Flexible electronics have been recently paid much attention. A flexible substrate (Organic resin film) is indispensable component for flexible devices. Though PET film is low-cost organic film, low heat-resistance of ...Flexible electronics have been recently paid much attention. A flexible substrate (Organic resin film) is indispensable component for flexible devices. Though PET film is low-cost organic film, low heat-resistance of PET film limits its application as a flexible device substrate. We have developed heat-resistant PET which does not deteriorate even at 190°C heat treatment for one hour. An excimer light was irradiated onto a polysi-lazane (PHPS: perhydropolysilane)-coated film to form a dense silicon-dioxide (SiO2) layer on a PET film, and the heat-resistance property of the formed film was examined. Changes of surface state and cross-sectional structure of the formed film due to heat treatment were investigated by scanning electron microscope (SEM) and transmission electron microscope (TEM). Compared to normal PET, which is deteriorated and whitened by heat treatment of about 110°C - 120°C, the SiO2-coated PET film maintains transparency and does not deteriorate after heat treatment at 180°C - 190°C for one hour. This high heat resistance is due to a dense SiO2 film formed on the surface that prevents surface precipitation and crystallization of low-molecular-weight oligomers (which are the cause of thermal degradation of PET). It is expected that enhancing the heat resistance of PET—which has high versatility and low cost—to about 180°C to 190°C will allow SiO2-film-coated PET to be developed as a film substrate for flexible devices.展开更多
In_2O_3∶SnO_2(ITO) thin films were fabricated on the substrate of flexible polyethylene terephthalate(PET) by DC magnetron sputtering from a ceramic target of In_2O_3/SnO_2(90∶10). Properties of the thin films were ...In_2O_3∶SnO_2(ITO) thin films were fabricated on the substrate of flexible polyethylene terephthalate(PET) by DC magnetron sputtering from a ceramic target of In_2O_3/SnO_2(90∶10). Properties of the thin films were characterized by X-ray diffraction(XRD), four-point probe, Hall-effect measurement, UV-Vis spectrophotometer, and scanning electron microscopy(SEM). The effects of sputtering pressure, oxygen partial pressure and deposition temperature on properties of microstructure and optoelectronics properties of PET/ITO thin films were investigated in detail. High-quality ITO thin films on PET substrates with the resistivity as low as 8.5×10-4 Ω·cm and the optical transmittance over 80% in the visible spectrum range were obtained.展开更多
文摘The effects of excimer light irradiation on polysilazane coatings formed on PET films with vacuum-evaporated SiO2 coatings and the effects of these coatings on gas barrier characteristics have been investigated. The temperature during light irradiation has a large effect on the coating’s molecular structure and gas barrier characteristics. When irradiation was performed at 100℃, the polysilazane coating transformed into a silica coating, and a compact silica coating at a much lower temperature than with heat treatment alone was produced. Surface irregularities in the vapor-deposited silica coating were smoothed out by the formation of a polysilazane coating, which was transformed into a compact silica coating when irradiated with light, resulting in a significant improvement in the gas barrier characteristics. The water vapor permeability of the thin coating irradiated with excimer light at 100℃ showed only 0.04 g/m2•day (40℃, 90% RH). According to the results of investigation of temperature variation of water-vapor permeability, it is inferred that the developed film has an excellent gas barrier value, namely, 4.90 × 10–4 g/m2•day at 25℃. This gas barrier coated PET film is transparent and flexible, and can be used in the fabrication of flexible electronics. Also, the proposed fabrication method effectively provides a simple low-cost and low-temperature fabrication technique without the need for high vacuum facility.
文摘Recently, the industry and productions have been rapidly developed by the advancement of science and technology. On the other hand, the dwindling natural resources and the global warming increasingly pose a severe problem to our life in near future. Indeed, solar photovoltaic (PV) has been attractive as one of the alternative energy resource to oil. However, some problems such as the reduction of electromotive force and the degradation of back-sheet influence the properties of the long-term life of the PV panel system. In this research, we used the high- and low-molecular-weight PET film in order to evaluate the effect of molecular weight for the hydrolysis of PET under the acceleration degradation test. As results, the mechanical properties of PET film were decreased with increasing the acceleration degradation time. In addition, it was found that the dielectric breakdown strength of PET film indicated the similar tendency with the mechanical properties. Accordingly, the non-destructive analytical technique, i.e. the partial discharge measurement makes it easy to evaluate the degradation of PET film without any damage or cut out for the film.
文摘Flexible electronics have been recently paid much attention. A flexible substrate (Organic resin film) is indispensable component for flexible devices. Though PET film is low-cost organic film, low heat-resistance of PET film limits its application as a flexible device substrate. We have developed heat-resistant PET which does not deteriorate even at 190°C heat treatment for one hour. An excimer light was irradiated onto a polysi-lazane (PHPS: perhydropolysilane)-coated film to form a dense silicon-dioxide (SiO2) layer on a PET film, and the heat-resistance property of the formed film was examined. Changes of surface state and cross-sectional structure of the formed film due to heat treatment were investigated by scanning electron microscope (SEM) and transmission electron microscope (TEM). Compared to normal PET, which is deteriorated and whitened by heat treatment of about 110°C - 120°C, the SiO2-coated PET film maintains transparency and does not deteriorate after heat treatment at 180°C - 190°C for one hour. This high heat resistance is due to a dense SiO2 film formed on the surface that prevents surface precipitation and crystallization of low-molecular-weight oligomers (which are the cause of thermal degradation of PET). It is expected that enhancing the heat resistance of PET—which has high versatility and low cost—to about 180°C to 190°C will allow SiO2-film-coated PET to be developed as a film substrate for flexible devices.
基金Chinese Ministry of Science and Technology for financial support under construct(2003AA513010)
文摘In_2O_3∶SnO_2(ITO) thin films were fabricated on the substrate of flexible polyethylene terephthalate(PET) by DC magnetron sputtering from a ceramic target of In_2O_3/SnO_2(90∶10). Properties of the thin films were characterized by X-ray diffraction(XRD), four-point probe, Hall-effect measurement, UV-Vis spectrophotometer, and scanning electron microscopy(SEM). The effects of sputtering pressure, oxygen partial pressure and deposition temperature on properties of microstructure and optoelectronics properties of PET/ITO thin films were investigated in detail. High-quality ITO thin films on PET substrates with the resistivity as low as 8.5×10-4 Ω·cm and the optical transmittance over 80% in the visible spectrum range were obtained.
