Organic electroluminescent display device comprising polydiacetylene

Abstract

An organic electroluminescent (EL) display device includes organic EL elements respectively located in pixels and a thin film encapsulation structure covering the pixels. Each of the organic EL elements has a microcavity structure. A thickness of an organic EL layer in the blue pixel and a thickness of an organic EL layer in the red pixel are deviated from of the optimum value of respective microcavity structures. The device further includes a first polydiacetylene layer selectively provided only on the thin film encapsulation structure on the blue pixel, which exhibits blue color and further narrows a spectral width of the blue light, a second polydiacetylene layer selectively provided only on the thin film encapsulation structure on the red pixel, which exhibits red color and further narrows a spectral width of the red light, and no polydiacetylene layer on the thin film encapsulation structure on the organic EL element that emits only the green light. The first and second polydiacetylene layers are formed of a polymer of 10,12-pentacosadiynoic acid.

1 . An organic electroluminescent display device including a plurality of pixels, the organic electroluminescent display device comprising:
 an element substrate including a substrate, a plurality of organic electroluminescent elements supported by the substrate and respectively located in the plurality of pixels, and a bank layer defining the plurality of pixels; and   a thin film encapsulation structure covering the plurality of pixels,   wherein each of the plurality of organic electroluminescent elements has a microcavity structure,   wherein the thin film encapsulation structure includes a first inorganic barrier layer and an organic barrier layer in contact with a top surface or a bottom surface of the first inorganic barrier layer,   wherein the plurality of pixels include a red pixel having an organic electroluminescent element that emits only red light, a green pixel having an organic electroluminescent element that emits only green light and a blue pixel having an organic electroluminescent element that emits only blue light,   a thickness of an organic electroluminescent layer included in the blue pixel and a thickness of an organic electroluminescent layer included in the red pixel are deviated from of the optimum value of respective microcavity structures,   wherein the organic electroluminescent display device further includes a first polydiacetylene layer selectively provided only on the thin film encapsulation structure on the blue pixel, which exhibits blue color and further narrows a spectral width of the blue light, a second polydiacetylene layer selectively provided only on the thin film encapsulation structure on the red pixel, which exhibits red color and further narrows a spectral width of the red light, and no polydiacetylene layer on the thin film encapsulation structure on the organic electroluminescent element that emits only the green light, and   wherein the first and second polydiacetylene layers are formed of a polymer of 10,12-pentacosadiynoic acid.   
     
     
         2 . The organic electroluminescent display device of  claim 1 ,
 wherein the organic barrier layer included in the thin film encapsulation structure is in contact with the top surface of the first inorganic barrier layer and includes a plurality of solid portions distributed discretely,   wherein the thin film encapsulation structure further includes a second inorganic barrier layer in contact with the top surface of the first inorganic barrier layer and top surfaces of the plurality of solid portions of the organic barrier layer, and   the first and second polydiacetylene layers are formed on the second inorganic barrier layer.   
     
     
         3 . The organic electroluminescent display device of  claim 1 , wherein the first and second polydiacetylene layers are semiconductive. 
     
     
         4 . The organic electroluminescent display device of  claim 3 , wherein the first polydiacetylene layer has a specific resistance smaller than, or equal to, 1×10 −1  Ωcm. 
     
     
         5 . The organic electroluminescent display device of  claim 1 , further comprising an ultraviolet absorbing layer located on the first and second polydiacetylene layers. 
     
     
         6 . The organic electroluminescent display device of  claim 1 , wherein the first inorganic barrier layer is formed of silicon nitride. 
     
     
         7 . The organic electroluminescent display device of  claim 1 , wherein the first and second polydiacetylene layers each have a thickness of 0.5 μm or greater and 2.0 μm or less. 
     
     
         8 . The organic electroluminescent display device of  claim 1 , wherein the first polydiacetylene layer provides a transmission spectrum of blue light in which the blue light has a peak wavelength in the range of 460 nm or longer and 470 nm or shorter. 
     
     
         9 . The organic electroluminescent display device of  claim 8 , wherein the first polydiacetylene layer has a transmittance for the blue light higher than, or equal to, 80% at the peak wavelength thereof. 
     
     
         10 . The organic electroluminescent display device of  claim 1 , wherein the second polydiacetylene layer provides a transmission spectrum of red light in which the red light has a peak wavelength in the range of 610 nm or longer and 630 nm or shorter. 
     
     
         11 . The organic electroluminescent display device of  claim 10 , wherein the second polydiacetylene layer has a transmittance for the red light higher than, or equal to, 90% at the peak wavelength thereof.