Sharp Kabushiki Kaisha Corporation

Masaru Nagai

Chong Li

Koji Kawaguchi

Naoyuki Kanai

Yuko Nakamata

Toshio Hama

A color conversion film that absorbs light from an organic electroluminescent part emitting blue-green light and converts the light to visible light at a longer wavelength. The color conversion film includes two different dyes. A first dye is a polymer dye with an average molecular weight of 1000 to 1,000,000 that absorbs light incident on the color conversion film and transfers the energy of the light to a second dye. The second dye is a dye that receives the energy from the first dye and emits light. With a multicolor-emitting, organic electroluminescent device including the color conversion film, it is possible to achieve excellent conversion efficiency without increasing the thickness of the color conversion film as in a conventional device using a binder resin. Such an organic electroluminescent device may include as well a pair of electrodes at least one of which is a transparent electrode, and an organic electroluminescent layer sandwiched between the electrodes.

Color conversion film and multicolor-emitting, organic electroluminescent device comprising the color conversion film

This invention provides a method capable of fabricating, by simple manufacturing processes, a color conversion layer which realizes high-efficiency color conversion characteristics without greatly increasing the film thickness of the color conversion layer. Further, this invention provides a color conversion layer manufactured by this method, and an organic EL element which includes this color conversion layer. By means of a method in which a polymer material having a weight-average molecular weight in a specific range is brought into contact with a color conversion material layer, and the polymer material is caused to intrude into the color conversion layer by a diffusion phenomenon, concentration quenching in the color conversion layer can be suppressed, and the fluorescence quantum yield can be increased.

Color conversion layer and manufacturing method for same

The present invention provides a color conversion film that can maintain sufficient conversion light intensity without increasing the thickness thereof, and a multicolor light-emitting organic EL device that uses such a film. The color conversion film of the invention includes a polymeric dye material that has a weight-average molecular weight of at least 1,000 but not more than 100,000 and that is composed of a first dye unit and a second dye unit. The first dye unit absorbs light incident on the color conversion film and transfers energy of the absorbed incident light to the second dye unit. The second dye unit receives the energy from the first dye unit and emits light.

Color conversion film using polymeric dye, and multicolor light-emitting organic EL device using same

A color conversion film is disclosed that absorbs light from an organic electroluminescent part emitting blue-green light and converts the light to visible light at a longer wavelength. The color conversion film includes two different dyes. A first dye is a polymer dye with an average molecular weight of 1000 to 1,000,000 that absorbs light incident on the color conversion film and transfers the energy of the light to a second dye. The second dye is a dye that receives the energy from the first dye and emits light. With a multicolor-emitting, organic electroluminescent device including the color conversion film, it is possible to achieve excellent conversion efficiency without increasing the thickness of the color conversion film as in a conventional device using a binder resin.

Provided are a color conversion film that maintains sufficient converted light intensity over a long period of time without increasing its thickness and a multicolor light-emitting organic EL device that includes the color conversion film. The color conversion film contains a conjugated high molecular weight copolymer having a structure of formula (1) that has alternating fluorene group-containing repeating units and arylenevinylene repeating units, and has phenylene groups inserted as spacers on both ends of the fluorene groups 

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Nagano, Japan

Masaru Nagai