Light extraction sheet, organic electroluminescence element and illumination device

摘要

Disclosed is a novel light extraction sheet, which not only improves light extraction efficiency but suppresses color change with the angle of observation, an organic EL element employing this light extraction sheet, and an illumination device employing the element. The light extraction sheet is featured in that it comprises a transparent resin film and provided thereon, a light scatter layer containing a binder resin and light scattering particles with an average particle size of front 0.2 to 1.0 μm dispersed in the binder resin and a concavo-convex layer containing a binder resin and spherical particles with an average particle size of from 3 to 10 μm.

主权项

1. A light extraction sheet comprising:
a transparent resin film and provided thereon, a light scatter layer containing a first binder resin and light scattering particles with an average particle size of from 0.2 to 1.0 μm dispersed in the first binder resin, and a concavo-convex layer containing a second binder resin and spherical particles with an average particle size of from 3 to 10 μm, wherein a content of the spherical particles in the concavo-convex layer is from 20 to 70% by volume of the second binder resin, wherein the sheet has a haze of not less than 98%, and wherein the light scatter layer and the concavo-convex layer are disposed on a same side of the transparent resin film, and the light scatter layer is disposed between the transparent resin film and the concavo-convex layer.