Adhesive composition
Provided are an adhesive composition and an organic electronic device (OED) including the same, and more particularly, an adhesive composition, which may form a structure effectively blocking moisture or oxygen flowing into an OED from the outside, thereby ensuring the lifespan of the OED, realize a top-emission OED, and exhibit excellent adhesive durability and reliability, and excellent reliability at high temperature and high humidity, and an OED including the same.
1. An adhesive composition for encapsulating an organic electronic element, comprising:
an olefin-based resin having a weight average molecular weight of 100,000 or less, and
a curable compound,
wherein the olefin-based resin and the curable compound are included at 55 to 85 parts by weight and 15 to 45 parts by weight, respectively, and
wherein the adhesive composition has a viscoelastic ratio (R) of 15 to 75%, measured by General Equation 1:
R=J i /J 60 ×100 [General Equation 1]
where J i is a deformation modulus of a specimen of the adhesive composition, after being cured, prepared in a circular shape having a diameter of 8 mm and a thickness of 200 μm, which is loaded in an advanced rheometric expansion system (ARES), and subjected to application of any one stress of 100 to 5000 Pa for one minute at a time of applying any one axial force of 100 to 200 g and 100° C., and J 60 is a deformation modulus measured one minute after the time of applying the axial force.
2. The adhesive composition of claim 1 ,
wherein the olefin-based resin has a water vapor transmission rate (WVTR) of 50 g/m 2 ·day or less and a curable compound.
3. The adhesive composition of claim 1 , wherein the olefin-based resin has one or more reactive functional groups.
4. The adhesive composition of claim 1 , further comprising:
an inorganic filler.
5. The adhesive composition of claim 1 , further comprising:
a moisture absorbent.
6. The adhesive composition of claim 5 , wherein the moisture absorbent is comprised at 5 to 100 parts by weight with respect to 100 parts by weight of the olefin-based resin.
7. The adhesive composition of claim 5 , wherein the moisture absorbent is one or more selected from the group consisting of P 2 O 5 , Li 2 O, Na 2 O, BaO, CaO, MgO, Li 2 SO 4 , Na 2 SO 4 , CaSO 4 , MgSO 4 , CoSO 4 , Ga 2 (SO 4 ) 3 , Ti(SO 4 ) 2 , NiSO 4 , CaCl 2 , MgCl 2 , SrCl 2 , YCl 3 , CuCl 2 , CsF, TaF 5 , NbF 5 , LiBr, CaBr 2 , CeBr 3 , SeBr 4 , VBr 3 , MgBr 2 , BaI 2 , MgI 2 , Ba(ClO 4 ) 2 and Mg(ClO 4 ) 2 .
8. The adhesive composition of claim 1 , wherein the curable compound comprises a heat-curable resin or a photocurable compound.
9. The adhesive composition of claim 8 , wherein the photocurable compound comprises a multifunctional active energy ray-polymerizable compound.
10. The adhesive composition of claim 8 , further comprising:
a curing agent or an initiator.
11. The adhesive composition of claim 8 , wherein the heat-curable resin is a resin comprising one or more heat-curable functional groups.
12. The adhesive composition of claim 11 , wherein the heat-curable functional group comprises an epoxy group, an isocyanate group, a hydroxyl group, a carboxyl group or an amide group.