ENCAPSULATING COMPOSITION

Abstract

Provided is a composition for encapsulating an organic electronic element, comprising an olefin-based resin having at least one reactive functional group, a multifunctional acrylic oligomer, and a monofunctional acrylic oligomer, wherein the monofunctional acrylic oligomer is present in an amount of 7 to 30 parts by weight relative to 100 parts by weight of the olefin-based resin. Also provided are an organic electronic device comprising the composition, and methods for preparing the organic electronic device.

Claims

1. A composition for encapsulating an organic electronic element, comprising: an olefin-based resin having at least one reactive functional group; a multifunctional acrylic oligomer; and a monofunctional acrylic oligomer, wherein the monofunctional acrylic oligomer is present in an amount of 7 to 30 parts by weight relative to 100 parts by weight of the olefin-based resin.

2. The composition for encapsulating an organic electronic element according to claim 1, wherein the olefin-based resin has a weight average molecular weight of 100,000 g/mol or less.

3. The composition for encapsulating an organic electronic element according to claim 1, wherein the reactive functional group comprises an acid anhydride group, a carboxyl group, an epoxy group, an amino group, a hydroxyl group, an isocyanate group, an oxazoline group, an oxetane group, a cyanate group, a phenol group, a hydrazide group or an amide group.

4. The composition according to claim 1, wherein the multifunctional acrylic oligomer or the monofunctional acrylic oligomer has a weight average molecular weight in a range of 500 g/mol to 50,000 g/mol.

5. The composition according to claim 1, wherein the multifunctional acrylic oligomer is present in an amount of 8 to 60 parts by weight relative to 100 parts by weight of the olefin-based resin.

6. The composition according to claim 1, further comprising a reactive diluent.

7. The composition according to claim 6, wherein the reactive diluent has a weight average molecular weight of less than 500 g/mol.

8. The composition according to claim 6, wherein the reactive diluent comprises an epoxy compound, an oxetane compound or an acrylate monomer.

9. The composition according to claim 6, wherein the reactive diluent is present in an amount of 10 to 50 parts by weight relative to 100 parts by weight of the olefin-based resin.

10. The composition according to claim 1, further comprising an inorganic filler.

11. The composition according to claim 10, wherein the inorganic filler has a BET specific surface area in a range of 35 m.sup.2/g to 500 m.sup.2/g.

12. The composition according to claim 10, wherein the inorganic filler is present in an amount of 0.1 parts by weight to 30 parts by weight relative to 100 parts by weight of the olefin-based resin.

13. (canceled)

14. The composition according to claim 1, comprising an initiator which comprises a cationic initiator or a radical initiator.

15. The composition according to claim 14, wherein the cationic initiator is present in an amount of 0.01 to 5 parts by weight relative to 100 parts by weight of the olefin-based resin, and the radical initiator is present in an amount of 3 to 15 parts by weight relative to 100 parts by weight of the olefin-based resin.

16. The composition according to claim 1, further comprising a moisture adsorbent.

17. (canceled)

18. The composition according to claim 6, wherein the olefin-based resin, the multifunctional acrylic oligomer, the monofunctional acrylic oligomer and the reactive diluent are present in weight ratios of 45 to 75 parts by weight, 8 to 21 parts by weight, 3 to 15 parts by weight and 1 to 21 parts by weight, respectively.

19. The composition according to claim 1, satisfying Equation 1 below:
V/V.sub.01.4[Equation 1] wherein V is the viscosity of the encapsulating composition after irradiation with light of 100 mJ/cm.sup.2 at a wavelength of 395 nm and an intensity of 100 mW/cm.sup.2, V.sub.0 is the viscosity of the encapsulating composition before irradiation with the light, and the viscosity is measured at a temperature of 25 C., a strain of 5% and a frequency of 1 Hz.

20. An organic electronic device comprising: a substrate; an organic electronic element formed on the substrate; a side sealing layer on the periphery of the substrate and surrounding the side of the organic electronic element; and the composition according to claim 1.

21. The organic electronic device according to claim 20, further comprising a top sealing layer covering the entire surface of the organic electronic element, wherein the top sealing layer and the side sealing layer are present on the same plane.

22. A method for preparing an organic electronic device, comprising steps of: applying the composition of claim 1 on the periphery of a substrate on which an organic electronic element is formed, so as to surround the side of the organic electronic element; and curing the composition.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0076] FIG. 1 is a cross-sectional view showing an organic electronic device according to one example of the present invention.

EXPLANATION OF REFERENCE NUMERALS

[0077] 1: encapsulating composition [0078] 10: side sealing layer [0079] 11: top sealing layer [0080] 21: substrate [0081] 22: cover substrate [0082] 23: organic electronic element

BEST MODE

[0083] Hereinafter, the present invention will be described in more detail by way of 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.

[0084] Hereinafter, in Examples and Comparative Examples, as the olefin-based resin, an acid anhydride-modified polyisobutylene resin (BASF, Mn 1000 g/mol, Glissopal SA, hereinafter PIBSA) and polyisobutylene (B14 from BASF, Mw=60,000 g/mol, hereinafter PIB) were used. As the bifunctional (multifunctional) acrylic oligomer, epoxy acrylate (Sartomer, CN110, Mw 870 g/mol) and urethane acrylate (Sartomer, CN 9013, Mw 19,500 g/mol) were used and as the monofunctional acrylic oligomer, epoxy acrylate (Sartomer, CN131, Mw 810 g/mol) and polyester acrylate (Sartomer, CN3108, Mw 8700 g/mol) were used. As the reactive diluent, an alicyclic epoxy resin (Daicel, Celloxide2021P, epoxy equivalent 130 g/eq, viscosity 250 cPs, Mw: 270 g/mol, hereinafter C2021P), an oxetane compound (OXT-212 from TOAGOSEI, Mw: 228.4 g/mol) and 1,6-hexanediol diacrylate (HDDA, Mw 226.3 g/mol) were used. As the inorganic filler, fumed silica (Aerosil, Evonik, R805, particle size 10 to 20 nm, BET=150 m.sup.2/g) was used and as the moisture adsorbent, calcium oxide (CaO, Aldrich) was used. As the photoinitiator, a photo-cationic initiator (San-apro, CPI-101A) and a radical initiator (BASF, Irgacure 819, hereinafter Irg819) were used.

Examples 1 to 5 and Comparative Examples 1 to 4

[0085] For the above composition, components were compounded in the weight ratios as shown in Table 1 below and introduced into a mixing vessel. In the mixing vessel, a uniform composition solution was prepared using a planetary mixer (Kurabo, KK-250s).

TABLE-US-00001 TABLE 1 Example Comparative Example 1 2 3 4 5 1 2 3 4 Olefin-based Resin PIBSA 65 70 50 65 65 65 60 72 PIB 60 Multifunctional CN110 15 22 15 20 10 Oligomer CN9013 10 20 10 15 Monofunctional CN131 5 5 20 5 Oligomer CN3108 10 10 8 10 Reactive Diluent C2021P 15 10 10 22 10 10 10 OXT-212 10 10 3 15 HDDA 5 5 Inorganic Filler R805 5 8 10 5 5 5 5 8 Moisture Adsorbent CaO 25 25 25 25 25 25 25 25 25 Initiator CPI-101A 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Irg819 5 5 5 5 5 5 5 5 5

[0086] Hereinafter, the physical properties in Examples and Comparative Examples were evaluated in the following manner.

[0087] 1. Viscosity Measurement

[0088] The viscosity of the encapsulating compositions prepared in Examples and Comparative Examples was measured using ARES G2 as a viscometer from TA as follows.

[0089] For the prepared encapsulating compositions, viscosity values at 1 Hz were each measured by frequency sweep using an 8 mm aluminum plate at a temperature of 25 C., a cell gap of 0.3 mm and a strain of 5%.

[0090] 2. UV Exposure Stability

[0091] The encapsulating composition solutions prepared in Examples or Comparative Examples were each applied on a soda-lime glass to a thickness of 200 m using a coating bar and irradiated with light of 100 mJ/cm.sup.2 at an intensity of 100 mW/cm.sup.2 using an LED 395 nm light source. Thereafter, viscosity values at 1 Hz were each measured by frequency sweep using an 8 mm aluminum plate at a temperature of 25 C., a cell gap of 0.3 mm and a strain of 5% (ARES-G2 from TA).

[0092] The viscosity before light irradiation was defined as V.sub.0 and the viscosity after light irradiation was defined as V, and then they were substituted into Equation 1 below, where in the case of being 1.4 or less, it was classified as excellent in stability.

V/V.sub.01.4[Equation 1]

[0093] 3. Heat Resistance and Moisture Resistance

[0094] The encapsulating composition solutions prepared in Examples or Comparative Examples were each applied on a 0.7 T soda-lime glass to a layer of 200 m using a coating bar. Then, a sample was prepared by laminating it with the same glass, the encapsulating composition was irradiated with light (metal halide lamp) having a wavelength range of the UV-A region band at a light quantity of 3 J/cm.sup.2 and then, heat was applied thereto in an oven at 100 C. for 3 hours. Then, the sample was held in a constant temperature and humidity chamber at 85 C. and 85% relative humidity for about 1000 hours.

[0095] The measurement of heat resistance was indicated as O in the case where there was no change in the inside and the side of the coating region and X in the case where voids occurred inside the coating region.

[0096] The measurement of moisture resistance was indicated as O in the case where there was no lifting of the region penetrated with moisture, A in the case where the glass was lifted due to the moisture penetration site and X in the case where the glass was peeled off due to the moisture penetration site.

[0097] 4. Moisture Barrier Property

[0098] Calcium was deposited to a size of 5 mm5 mm and a thickness of 100 nm on a glass substrate having a size of 100 mm100 mm and the encapsulating compositions of Examples and Comparative Examples were each applied to the edge part excluding the calcium. After it was laminated with a cover glass having a size of 100 mm100 mm in the coated state, UV irradiation was performed at a light quantity of 3 J/cm.sup.2 using a metal halide light source, and then heat was applied thereto in an oven at 100 C. for 1 hour. The obtained specimens are observed in a constant temperature and humidity chamber at 85 C. and 85% relative humidity to observe the time when calcium begins to become transparent by oxidation reaction due to moisture penetration. It was indicated as O in the case where the transparency start time was 850 hours or more, A in the case where the transparency start time was less than 850 hours and 500 hours or more, and X in the case where the transparency start time was less than 500 hours.

TABLE-US-00002 TABLE 2 Moisture Moisture UV exposure resistance/Heat barrier Viscosity stability resistance property Example 1 240,000 cP 1.06 / Example 2 275,000 cP 1.04 / Example 3 260,000 cP 1.09 / Example 4 320,000 cP 1.37 / Example 5 180,000 cP 1.07 / Comparative 235,000 cP 1.45 / Example 1 Comparative 267,000 cP 1.06 / X Example 2 Comparative 270,000 cP 1.05 /X Example 3 Comparative 480,000 cP 1.09 X/X X Example 4