ENCAPSULATION FILM

Abstract

The present disclosure relates to an encapsulation film and an organic electronic device comprising the same, which provides an encapsulation film having excellent resilience without causing plastic deformation, while having flexible and rollable characteristics, as well as implementing excellent moisture barrier characteristics, and an organic electronic device comprising the same. The encapsulation film includes an encapsulation composition which includes a block copolymer having a first block derived from a monomer having a glass transition temperature of 0° C. or higher, and a multifunctional oligomer, where, after the encapsulation film is stretched 200% (2 times the existing length) in the longitudinal direction under conditions of a temperature of 25° C. and 60% relative humidity and left for 24 hours, the degree of restoration at the time of removing the stretched force and measuring the length after 1 hour is within 110% of the existing length.

Claims

1. An encapsulation film comprising an encapsulation composition, wherein the encapsulation composition comprises: a block copolymer having a first block derived from a monomer having a glass transition temperature of 0° C. or higher, and a multifunctional oligomer, wherein after the encapsulation film is stretched 200% (2 times the original length) in the longitudinal direction under conditions of a temperature of 25° C. and 60% relative humidity and left for 24 hours, the degree of restoration at the time of removing the stretched force and measuring the length after 1 hour is within 110% of the original length.

2. The encapsulation film according to claim 1, wherein the block copolymer and the multifunctional oligomer are included in the encapsulation composition in amounts of 30 to 90 parts by weight and 5 to 48 parts by weight, respectively.

3. The encapsulation film according to claim 1, wherein the block copolymer further comprises a second block, and the second block has a glass transition temperature lower than that of the first block.

4. The encapsulation film according to claim 3, wherein the second block is derived from a monomer having a glass transition temperature of less than 0° C.

5. The encapsulation film according to claim 1, wherein the first block is derived from a monomer having a glass transition temperature of 50° C. to 300° C.

6. The encapsulation film according to claim 1, wherein the block copolymer comprises at least one or more unsaturated groups in the molecular structure.

7. The encapsulation film according to claim 1, wherein the block copolymer has a weight average molecular weight in a range of 10,000 g/mol to 2,000,000 g/mol.

8. The encapsulation film according to claim 1, wherein the multifunctional oligomer comprises two or more active energy ray polymerizable functional groups.

9. The encapsulation film according to claim 1, wherein the multifunctional oligomer has a weight average molecular weight in a range of 500 g/mol to 50,000 g/mol.

10. The encapsulation film according to claim 1, wherein the multifunctional oligomer comprises an acrylic compound or a vinyl compound.

11. The encapsulation film according to claim 1, wherein the encapsulation composition further comprises a reactive monomer.

12. The encapsulation film according to claim 11, wherein the reactive monomer comprises one or more active energy ray polymerizable functional groups.

13. The encapsulation film according to claim 11, wherein the reactive monomer comprises a monofunctional or multifunctional acrylic compound or a monofunctional or multifunctional vinyl compound.

14. The encapsulation film according to claim 11, wherein the block copolymer, the multifunctional oligomer and the reactive monomer are included in the encapsulation composition in amounts of 30 to 90 parts by weight, 5 to 48 parts by weight and 1 to 40 parts by weight, respectively.

15. The encapsulation film according to claim 1, wherein the multifunctional oligomer is included in the encapsulation composition in a range of 20 to 95 parts by weight relative to 100 parts by weight of the block copolymer.

16. The encapsulation film according to claim 1, wherein the encapsulation composition further comprises a moisture adsorbent.

17. The encapsulation film according to claim 16, wherein the moisture adsorbent is included in the encapsulation composition in a range of 5 to 200 parts by weight relative to 100 parts by weight of the block copolymer.

18. The encapsulation film according to claim 1, wherein the encapsulation composition further comprises a curing agent or an initiator.

19. The encapsulation film according to claim 1, wherein the encapsulation composition further comprises a silane coupling agent.

20. The encapsulation film according to claim 1, comprising an encapsulation layer, wherein the encapsulation layer has a single layer or a multi-layer structure of two or more layers.

21. An organic electronic device, comprising: a substrate; an organic electronic element formed on the substrate; and the encapsulation film of claim 1 encapsulating the entire surface of the organic electronic element.

22. A method for preparing an organic electronic device, comprising: a step of applying the encapsulation film of claim 1 on a substrate on which an organic electronic element is formed so as to cover the organic electronic element.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0065] FIG. 1 is a cross-sectional view showing an exemplary organic electronic device.

EXPLANATION OF REFERENCE NUMERALS

[0066] 1: substrate [0067] 2: organic electronic element [0068] 3: encapsulation layer or encapsulation film [0069] 4: metal layer

DETAILED DESCRIPTION

[0070] Hereinafter, the present invention will be described in more detail through examples according to the present invention and comparative examples not according to the present invention, but the scope of the present invention is not limited by the following examples.

Example 1

[0071] A styrene-butadiene-styrene copolymer (SBS, Mw: 100,000 g/mol, LG Chem) as a block copolymer, a urethane acrylate oligomer (CN9021NS, Mw: 5000 g/mol, Satomer) as a multifunctional oligomer and trimethyrolpropane triacrylate (TMPTA, Aldrich) as a reactive monomer were each introduced to a reaction vessel at a weight ratio of 60:30:10 (SBS: CN9021NS: TMPTA), and 5 parts by weight of 1-hydroxy-cyclohexylphenyl ketone (Irgarcure 184, Ciba) as a photoinitiator, 50 parts by weight of CaO (Aldrich) as a moisture adsorbent and 0.5 parts by weight of a silane coupling agent (KBM-5103, Shin-Etsu) were introduced thereto, and then the mixture was diluted with toluene to a solid content of 40 wt % or so to prepare an encapsulation composition coating solution.

[0072] An encapsulation film was produced by applying the prepared solution to the release surface of the release PET and drying it in an oven at 110° C. for 3 minutes to form an encapsulation layer having a thickness of 50 μm.

Example 2

[0073] An encapsulation composition and an encapsulation film were produced in the same method as in Example 1, except that a styrene-butadiene-styrene copolymer (SBS, Mw: 100,000 g/mol, LG Chem) as a block copolymer, a urethane acrylate oligomer (CN9021NS, Mw: 5000 g/mol, Satomer) as a multifunctional oligomer and trimethyrolpropane triacrylate (TMPTA, Aldrich) were each introduced to a reaction vessel at a weight ratio of 50:25:25 (SBS: CN9021NS: TMPTA).

Example 3

[0074] An encapsulation composition and an encapsulation film were produced in the same method as in Example 1, except that a styrene-butadiene-styrene copolymer (SBS, Mw: 100,000 g/mol, LG Chem) as a block copolymer, a urethane acrylate oligomer (CN9021NS, Mw: 5000 g/mol, Satomer) as a multifunctional oligomer and lauryl acrylate (LA, Aldrich) as a reactive monomer were introduced to a reaction vessel at a weight ratio of 60:35:5 (SBS: CN9021NS: LA).

Comparative Example 1

[0075] An encapsulation composition and an encapsulation film were produced in the same method as in Example 1, except that a urethane acrylate oligomer (CN1073NS, Mw: 3000 g/mol) as a monofunctional oligomer was used instead of CN9021NS as the multifunctional oligomer.

Comparative Example 2

[0076] An encapsulation composition and an encapsulation film were produced in the same method as in Example 1, except that a random copolymer isobutylene-isoprene rubber (IIR, Exxon) was used instead of the styrene-butadiene-styrene block copolymer.

Comparative Example 3

[0077] An encapsulation composition and an encapsulation film were produced in the same method as in Example 1, except that a styrene-butadiene-styrene copolymer (SBS, Mw: 100,000 g/mol, LG Chem) as a block copolymer, a urethane acrylate oligomer (CN9021NS, Mw: 5000 g/mol, Satomer) as a multifunctional oligomer and trimethyrolpropane triacrylate (TMPTA, Aldrich) as a reactive monomer were each introduced to a reaction vessel at a weight ratio of 20:60:20 (SBS: CN9021NS: TMPTA).

[0078] Physical properties of the produced encapsulation films were evaluated as follows. Evaluation of the physical properties proceeded after curing the encapsulation film, where in the case of thermal curing, the curing was performed at 100° C. for 1 hour or more, and in the case of UV curing, ultraviolet rays of 1 J/cm.sup.2 or more were irradiated.

Experimental Example 1—Restoration Characteristics

[0079] After the encapsulation films produced in Examples and Comparative Examples were stretched 200% (2 times the existing length) in the longitudinal direction under conditions of a temperature of 25° C. and 60% relative humidity and left for 24 hours, the degree of restoration at the time of removing the stretched force and measuring the length after 1 hour was evaluated.

Experimental Example 2—Heat Resistance Durability

[0080] The films produced in Examples and Comparative Examples were laminated to soda lime glass, and samples were prepared by vacuum bonding soda lime glass together. The samples were placed in an oven at 85° C. for 1000 hours to observe changes. It was observed whether air bubbles were generated between the glass substrate and the encapsulation film. When seen with the naked eye, it was indicated as X in the case where any bubble occurred between the glass substrate and the encapsulation film, and it was indicated as 0 in the case where no bubble occurred.

Experimental Example 3—Moisture-Heat Resistance Durability

[0081] The samples prepared in Experimental Example 2 were left under 85° C. and 85% relative humidity for 1000 hours to observe changes.

[0082] It was observed whether lifting occurred at the interface between the glass substrate and the encapsulation film. When seen with the naked eye, it was indicated as X in the case where any lifting occurred at the interface between the glass substrate and the encapsulation film, and it was indicated as 0 in the case where no lifting occurred.

Experimental Example 4—Moisture Barrier Performance

[0083] Calcium was deposited on a glass substrate having a size of 100 mm×100 mm to a size of 5 mm×5 mm and a thickness of 100 nm, and encapsulation films of Examples and Comparative Examples were applied to cover all of the calcium. After bonding with a cover glass having a size of 100 mm×100 mm on the film, it was cured under the curing conditions as described above. The resulting specimens were observed in a constant temperature and humidity chamber at 85° C. and 85% relative humidity, and it was observed whether the calcium becomes transparent by an oxidation reaction due to moisture penetration. The time that it took for moisture to penetrate 3 mm (to become transparent) was measured.

TABLE-US-00001 TABLE 1 Restoration Heat Moisture-Heat Moisture Barrier Characteristics Resistance Resistance Performance (%) Durability Durability (hour) Example 1 105 ◯ ◯ 1800 2 103 ◯ ◯ 1700 3 108 ◯ ◯ 1500 Comparative 1 125 X ◯ 1300 Example 2 230 ◯ ◯ 1400 3 118 X X Lifting