Adhesive composition

Abstract

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.

Claims

1. A method of manufacturing an organic electronic device, comprising: applying an adhesive composition to a peripheral portion of a substrate on which an organic electronic element is formed to surround side surfaces of the organic electronic element; irradiating the adhesive composition with light; and heating the adhesive composition, wherein the adhesive composition comprises 15 to 45 parts by weight relative of a curable compound and 55 to 85 parts by weight of an olefin-based resin having a weight average molecular weight of 100,000 or less; wherein the adhesive composition has a viscoelastic ratio (R) of 15 to 75%, measured by General Equation 1:
R=J.sub.i/J.sub.60100[General Equation 1] where J.sub.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 m, 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.sub.60 is a deformation modulus measured one minute after the time of applying the axial force.

2. An organic electronic device, comprising: a substrate; an organic electronic element formed on the substrate; and a side encapsulation layer formed on peripheral portions of the substrate to surround side surfaces of the organic electronic element, and including an adhesive composition, wherein the adhesive composition comprises 15 to 45 parts by weight relative of a curable compound and 55 to 85 parts by weight of an olefin-based resin having a weight average molecular weight of 100,000 or less; wherein the adhesive composition has a viscoelastic ratio (R) of 15 to 75%, measured by General Equation 1:
R=J.sub.i/J.sub.60100[General Equation 1] where J.sub.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 m, 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.sub.60 is a debilitation modulus measured one minute after the time of applying the axial force.

3. The OED of claim 2, further comprising: an entire encapsulation layer for covering the entire surface of the organic electronic element, wherein the entire encapsulation layer is present in the same plane as the side encapsulation layer.

4. The organic electronic device of claim 2, the adhesive composition comprises an olefin-based resin having a water vapor transmission rate (WVTR) of 50 g/m.sup.2.Math.day or less.

5. The organic electronic device of claim 4, wherein the olefin-based resin has one or more reactive functional groups.

6. The organic electronic device of claim 4, the adhesive composition comprises an inorganic filler.

7. The organic electronic device of claim 4, the adhesive composition comprises a moisture absorbent.

8. The organic electronic device of claim 7, wherein the moisture absorbent is one or more selected from the group consisting of P.sub.2O.sub.5, Li.sub.2O, Na.sub.2O, BaO, CaO, MgO, Li.sub.2SO.sub.4, Na.sub.2SO.sub.4, CaSO.sub.4, MgSO.sub.4, CoSO.sub.4, Ga.sub.2(SO.sub.4).sub.3, Ti(SO.sub.4).sub.2, NiSO.sub.4, CaCl.sub.2, MgCl.sub.2, SrCl.sub.2, YCl.sub.3, CuCl.sub.2, CsF, TaF.sub.5, NbF.sub.5, LiBr, CaBr.sub.2, CeBr.sub.3, SeBr.sub.4, VBr.sub.3, MgBr.sub.2, BaI.sub.2, MgI.sub.2, Ba (ClO.sub.4).sub.2 and Mg (ClO.sub.4).sub.2.

9. The organic electronic device of claim 7, 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.

10. The organic electronic device of claim 4, wherein the curable compound comprises a beat-curable resin or a photocurable compound.

11. The organic electronic device of claim 10, wherein the photocurable compound comprises a multifunctional active energy ray-polymerizable compound.

12. The organic electronic device of claim 10, the adhesive composition comprises a curing agent or an initiator.

13. The organic, electronic device of claim 10, wherein the heat-curable resin is a resin comprising one or more heat-curable functional groups.

14. The organic electronic device of claim 13, wherein the heat-curable functional group comprises an epoxy group, an isocyanate group, a hydroxyl group, a carboxyl group or an amide group.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a cross-sectional view of an OED according to an exemplary embodiment of the present application.

LIST OF REFERENCE NUMERALS

(2) 1: adhesive 10: side encapsulation layer 11: entire encapsulation layer 21: substrate 22: cover substrate 23: organic electronic element

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

(3) Hereinafter, the present application will be described in further detail with reference to examples according to the present application and comparative examples not according to the present application, and the scope of the present application is not limited to the following examples.

Example 1

(4) As resin components, a polyisobutylene resin (PIB, Daelim, Mn=2,400 g/mol) as an olefin-based resin and an alicyclic epoxy resin (Kukdo Chemical, ST-4100D) as a curable compound were put into a mixing vessel in a weight ratio of 70:30 (PIB:ST-4100D) at room temperature. As a curing agent, 5 parts by weight of an imidazole-based curing agent (Shikoku, 2P4MHZ) was put into the vessel with respect to 100 parts by weight of the resin components. Meanwhile, as a moisture absorbent, 20 parts by weight of calcium oxide (CaO, Aldrich) was further put into the vessel with respect to 100 parts by weight of the resin components.

(5) A homogeneous composition solution was prepared by agitating the mixing vessel using a planetary mixing device (Kurabo Industries, KK-250s).

Example 2

(6) As resin components, a polyisobutylene resin (PIB, Daelim, Mn=2,400 g/mol) as an olefin-based resin and polybutadiene diacrylate (Sartomer, CN307) as a curable compound were put into a mixing vessel in a weight ratio of 70:30 (PIB:CN307) at room temperature. Subsequently, as a radical initiator, about 1 part by weight of 2,2-dimethoxy-1,2-diphenylethane-1-one (Irgacure 651, Ciba) was put into the vessel with respect to 100 parts by weight of the resin components. Meanwhile, as a moisture absorbent, 20 parts by weight of calcium oxide (CaO, Aldrich) was further put into the vessel with respect to 100 parts by weight of the resin components.

(7) A homogeneous composition solution was prepared by agitating the mixing vessel using a planetary mixing device (Kurabo Industries, KK-250s).

Example 3

(8) As resin components, a polyisobutylene resin (PIB, Daelim, Mn=2,400 g/mol) as an olefin-based resin, and an alicyclic epoxy resin (Kukdo Chemical, ST-4100D) and polybutadiene diacrylate (Sartomer, CN307) as curable compounds were put into a mixing vessel in a weight ratio of 60:20:20 (PIB:ST-4100D:CN307) at room temperature. Subsequently, as a radical initiator, about 1 part by weight of 2,2-dimethoxy-1,2-diphenylethane-1-one (Irgacure 651, Ciba) was put into the vessel with respect to 100 parts by weight of the resin components, and as a curing agent, 5 parts by weight of an imidazole-based curing agent (Shikoku, 2P4MHZ) was put into the vessel with respect to 100 parts by weight of the resin components. Meanwhile, as a moisture absorbent, 20 parts by weight of calcium oxide (CaO, Aldrich) was further put into the vessel with respect to 100 parts by weight of the resin components.

(9) A homogeneous composition solution was prepared by agitating the mixing vessel using a planetary mixing device (Kurabo Industries, KK-250s).

Comparative Example 1

(10) An adhesive composition was prepared by the same method as described in Example 1, except that a polyisobutylene resin (PIB, Daelim, Mn=2,400 g/mol) as an olefin-based resin and an alicyclic epoxy resin (Kukdo Chemical, ST-4100D) as a curable compound were put into a mixing vessel in a weight ratio of 90:10 (PIB:ST-4100D).

Comparative Example 2

(11) An adhesive composition was prepared by the same method as described in Example 1, except that a polyisobutylene resin (PIB, Daelim, Mn=2,400 g/mol) as an olefin-based resin and an alicyclic epoxy resin (Kukdo Chemical, ST-4100D) as a curable compound were put into a mixing vessel in a weight ratio of 50:50 (PIB:ST-4100D).

Comparative Example 3

(12) An adhesive composition was prepared by the same method as described in Example 2, except that a polyisobutylene resin (PIB, Daelim, Mn=2,400 g/mol) as an olefin-based resin and polybutadiene diacrylate (Sartomer, CN307) as a curable compound were put into a mixing vessel in a weight ratio of 90:10 (PIB:CN307).

Comparative Example 4

(13) An adhesive composition was prepared by the same method as described in Example 2, except that a polyisobutylene resin (PIB, Daelim, Mn=2,400 g/mol) as an olefin-based resin and polybutadiene diacrylate (Sartomer, CN307) as a curable compound were put into a mixing vessel in a weight ratio of 40:60 (PIB:CN307).

Comparative Example 5

(14) An adhesive composition was prepared by the same method as described in Example 3, except that a polyisobutylene resin (PIB, Daelim, Mn=2,400 g/mol) as an olefin-based resin, and an alicyclic epoxy resin (Kukdo Chemical, ST-4100D) and polybutadiene diacrylate (Sartomer, CN307) as curable compounds were put into a mixing vessel in a weight ratio of 50:20:30 (PIB:ST-4100D:CN307).

(15) Hereinafter, physical properties in the examples and comparative examples were evaluated by the following methods.

(16) 1. Viscoelastic Ratio (R)

(17) The adhesive composition prepared in each of the examples and the comparative examples was cured, thereby preparing a specimen having a diameter of 8 mm and a thickness of 200 m.

(18) The composition of each of Example 1 and Comparative Examples 1 and 2 was cured by heating in an oven at 100 C. for 3 hours, the composition of each of Example 2 and Comparative Examples 3 and 4 was cured by irradiating the adhesive composition with light in the UV-A wavelength range at a dose of 5 J/cm.sup.2, and the composition of each of Example 3 and Comparative Example 5 was cured by irradiating the adhesive composition with light in the UV-A wavelength range at a dose of 5 J/cm.sup.2 and heating in an oven at 100 C. for 3 hours.

(19) The specimen was loaded in an ARES produced by TA, and subjected to measurement of J.sub.i and J.sub.60 while a stress of 5000 Pa was applied for one minute at 100 C. at the time of applying an axial force of 200 g, and thus a viscoelastic ratio (R) was calculated by General Equation 1. Meanwhile, J.sub.i is a deformation modulus measured at the time of applying the axial force to the specimen prepared from the adhesive composition, and J.sub.60 is a deformation modulus measured one minute after the time of applying the axial force.
R=J.sub.i/J.sub.60100[General Equation 1]

(20) 2. Compatibility

(21) Compatibility was evaluated with respect to the adhesive compositions of the examples and the comparative examples. Phase separation was examined after the prepared adhesive composition was left in a vessel at 25 C. for 3 days. When phase separation did not occur in the composition, it was denoted as O, when partial phase separation occurred, it was denoted as , and when phase separation into two layers occurred, it was denoted as X.

(22) 3. Moisture Barrier Property

(23) To investigate a moisture barrier property of the adhesive composition of each of the examples and the comparative examples, a calcium test was performed. In detail, 7 spots of calcium (Ca) having a size of 5 mm5 mm and a thickness of 100 nm were deposited onto a glass substrate having a size of 100 mm100 mm, the adhesive composition of each of the examples and the comparative examples was applied at a peripheral portion (edge) at 3 mm intervals from the calcium deposited spot using a dispenser, a cover glass laminated on each calcium deposited spot and was pressed so that the adhesive composition had a width of 3 mm. Afterward, the adhesive composition of each of Example 1, and Comparative Examples 1 and 2 was cured by heating in an oven at 100 C. for 3 hours, and the adhesive composition of each of Example 2 and Comparative Examples 3 and 4 was cured by irradiation of light in the UV-A wavelength range at a dose of 5 J/cm.sup.2 and heating in an oven at 100 C. for 3 hours. Afterward, the cured product was cut to obtain an encapsulated calcium (Ca) specimen having a size of 11 mm11 mm. The obtained specimen was placed in a constant temperature and humidity chamber at 85 C. and a relative humidity of 85%, and then the time when the calcium started becoming transparent due to an oxidation reaction caused by moisture permeation was evaluated, which is shown in Table 1.

(24) 4. Reliability at High Temperature and High Humidity

(25) The adhesive composition prepared in each of the examples and the comparative examples was applied to a 0.7 T soda lime glass, and the same type of a glass was laminated thereon. The adhesive composition prepared in each of Example 1, and Comparative Examples 1 and 2 was cured by heating in an oven at 100 C. for 3 hours, the adhesive composition prepared in each of Example 2 and Comparative Examples 3 and 4 was cured by irradiation of light in the UV-A wavelength range at a dose of 5 J/cm.sup.2 and the adhesive composition prepared in each of Example 3 and Comparative Example 5 was cured by irradiation of light in the UV-A wavelength range at a dose of 5 J/cm.sup.2 and heating in an oven at 100 C. for 3 hours.

(26) Afterward, a specimen was maintained in a constant temperature and humidity chamber at 85 C. and a relative humidity of 85% for about 800 hours, and observed to determine if lifting or bubbles was generated at an interface between a glass substrate and an adhesive layer. Through observation with the naked eye, when only moisture permeation was observed without a change in an adhesion state and bubbles, it was denoted as good, when the adhesive had a pore, bubbles or a defect, it was denoted as bubble generation, when the interface between the substrate and the adhesive layer was lifted and had a non-adhesive part, it was denoted as adhesion failure, and when the adhesive composition was insufficiently cured and thus the measurement failed, it was denoted as measurement failure.

(27) TABLE-US-00001 TABLE 1 Viscoelastic Moisture barrier Adhesive reliability ratio (R) property at high temperature % Compatibility hrs and high humidity Example1 40 710 Good Example2 34 600 Good Example3 39 680 Good Comparative 13 420 Bubble generation Example1 Comparative 78 300 Adhesion failure Example2 Comparative 7 340 Bubble generation Example3 Comparative Measurement X Measurement Measurement Example4 failure failure failure Comparative Measurement 450 Adhesion failure Example5 failure