Organic electroluminescent display device

1. An organic EL device, comprising:

a front substrate;

a rear substrate;

an organic EL unit disposed on the rear substrate; and

an encapsulation layer comprising a layered inorganic substance/polymer/curing agent nanocomposite encapsulating the organic EL unit,

wherein the encapsulation layer contacts the front substrate and the rear substrate to seal the space between the front substrate and the rear substrate, and

wherein a surface of the layered inorganic substance is substituted with a hydrophilic group.

2. The organic EL device of claim 1 , wherein the layered inorganic substance/polymer/curing agent nanocomposite is formed by intercalating a mixture of a polymer and a curing agent, or a reaction product of the mixture, in an interlayer of the inorganic substance.

3. The organic EL device of claim 1 , wherein the layered inorganic substance is at least a compound selected from the group consisting of a layered silicate, organoclay, modified organoclay, montmorillonytril, kaoline, mica, quartz, illite, calcite, hydrated sodium calcium aluminum magnesium silicate hydroxide, pyrophyllite, talc, vermiculite, sauconite, saponite, nontronite, amesite, baileychlore, chamosite, clinochlore, kaemmererite, cookeite, corundophilite, daphnite, delessite, gonyerite, nimite, odinite, orthochamosite, penninite, pannantite, rhipidolite, prochlore, sudoite, thuringite, kaolinite, dickite, and nacrite.

4. The organic EL device of claim 1 , wherein the polymer is selected from the group consisting of epoxy resin, epoxy silane, epoxy titania hybrid compound, epoxy zirconia, polystyrene, nylon, polyimide, and silanol.

5. The organic EL device of claim 1 , wherein the encapsulation layer is about 30 μm to about 500 μm thick.

6. The organic EL device of claim 1 , wherein the layered inorganic substance/polymer/curing agent nanocomposite has major peaks in terms of Bragg's 2θ angle to the Cuk-α characteristic X-ray wavelength at 1.541 Å at least at 1.67±0.3° and 5.1±0.3°.

7. An organic EL device, comprising:

a front substrate;

a rear substrate;

an organic EL unit disposed on the rear substrate; and

an encapsulation layer comprising a layered inorganic substance/polymer nanocomposite encapsulating the organic EL unit,

wherein the encapsulation layer contacts the front substrate and the rear substrate to seal the space between the front substrate and the rear substrate, and

wherein a surface of the layered inorganic substance is substituted with a hydrophilic group.

8. The organic EL device of claim 7 , wherein the layered inorganic substance is at least a compound selected from the group consisting of a layered silicate, organoclay, modified organoclay, montmorillonytril, kaoline, mica, quartz, illite, calcite, hydrated sodium calcium aluminum magnesium silicate hydroxide, pyrophyllite, talc, vermiculite, sauconite, saponite, nontronite, amesite, baileychlore, chamosite, clinochlore, kaemmererite, cookeite, corundophilite, daphnite, delessite, gonyerite, nimite, odinite, orthochamosite, penninite, pannantite, rhipidolite, prochlore, sudoite, thuringite, kaolinite, dickite, and nacrite.

9. The organic EL device of claim 7 , wherein the layered inorganic substance/polymer nanocomposite has major peaks in terms of Bragg's 2θ angle to the Cuk-α characteristic X-ray wavelength at 1.541 Å at least at 1.67±0.3° and 5.1±0.3°.

10. The organic EL device of claim 7 , wherein the polymer is selected from the group consisting of epoxy resin and epoxy silane.

11. The organic EL device of claim 1 , wherein the front substrate comprises a flat, non-etched glass substrate.

12. The organic EL device of claim 11 , wherein the encapsulation layer completely fills the space between the front substrate and the rear substrate having the organic EL unit disposed thereon.

13. The organic EL device of claim 7 , wherein the front substrate comprises a flat, non-etched glass substrate.

14. The organic EL device of claim 13 , wherein the encapsulation layer completely fills the space between the front substrate and the rear substrate having the organic EL unit disposed thereon.