Toray develops blue light emitting materials

April 30, 2008 - Japan

Toray Industries Inc announced that it has succeeded in developing blue light emitting materials, boasting the world’s highest levels of efficiency and pure color emissions, for use in full-color organic EL displays.

The combination of Toray’s proprietary molecular design technology and nano-dispersion technology was instrumental in the material achieving superior light emitting performances of luminous efficiency 6 cd/A (candela/ampere) and color purity (CIE(x,y) = (0.14,0.10)) in combination with Toray’s electron-transporting material.

Evaluation of these newly developed materials with respect to its applications is currently underway and Toray is committed to accelerating the process towards its early commercialization.

Organic EL display possesses various features including self-emission with superior visibility, suitability for slim products and high-speed response, and is attracting widespread attention as the next-generation flat panel display.

Further improvements in features, low power consumption in particular, are needed for full takeoff of the market, requiring the development of materials that achieve low driving voltage and high efficiency.

Toray has already succeeded in developing red light emitting materials with low driving voltage and high efficiency as well as electron-transporting material, and has been producing them commercially, with a number of panel manufacturers adopting these materials in their products.

Toray’s electron-transporting material in particular, with high electron-transporting property, has been highly acclaimed by users as a material that can contribute significantly towards lowering the power consumption of organic EL displays.

It, however, faced the issue of lowered emission performances caused when used with some of blue light emitting materials, and the problem was observed only in combination with the blue color of the three primary colors.
To address this issue, Toray embarked on the development of a proprietary blue light emitting materials (host, dopant material), which would achieve both low driving voltage with high emission performances in combination with Toray’s electron-transporting material.

Bringing together Toray’s proprietary molecular design technology and nano-dispersion technology enabled the maximum use of the electrical energy from the electrodes, resulting in the successful development of blue light emitting materials with the world’s best light emitting performances of luminous efficiency 6 cd/A (candela/ampere) and color purity (CIE(x,y) = (0.14,0.10)).

Moreover, an ideal combination of low driving voltage and long lifetime, which was difficult in existing blue light emitting devices, has been achieved in this development, with the new materials significantly improving the lifetime while maintaining low driving voltage.

This has enabled the use of Toray’s electron-transporting material as the common layer for all three primary colors emission layers and is expected to contribute to lower power consumption in displays as well as reduced process costs.

Moreover, Toray has been utilizing the knowledge gained from the development of red and blue light emitting materials in development of green light emitting material which is currently underway and has developed the base structure of dopant material having high color purity (CIE(x,y) = (0.22,0.72)).

Toray intends to continue promoting further research and development of materials and processes and aims to offer comprehensive solutions including key materials and technologies for organic EL display.

Under its new mid-term business strategies “Project Innovation TORAY 2010 (IT-2010),” Toray has identified “information, telecommunications and electronics” as one of the four major growing business fields.

With focus on “chemistry,” Toray is committed in putting into practice its corporate slogan of “Innovation by Chemistry” through the development of advanced materials by bringing together resin design technology, micro-fabrication technology and nano-technology.