Encapsulating composition, organic electronic device and method for manufacturing thereof

Abstract

The present application relates to an encapsulating composition and an organic electronic device comprising the same, and provides an encapsulating composition which can effectively block moisture or oxygen introduced into an organic electronic device from the outside to secure the lifetime of the organic electronic device, is possible to realize a top emission type organic electronic device, is applicable to an inkjet method, can provide a thin display and has excellent adhesion reliability.

Claims

1. An encapsulating composition comprising: 5 to 50 parts by weight of a curable compound having a cyclic structure in its molecular structure, and 25 to 80 parts by weight of a vinyl ether curable compound, wherein the curable compound having a cyclic structure does not comprise an vinyl ether group and an oxetane group.

2. The encapsulating composition according to claim 1, wherein the encapsulating composition satisfies Equation 1:
(BA)/A10020(%)[Equation 1] wherein, A is a thickness (m) of the encapsulating composition in a form of a sealing layer when the encapsulating composition is applied on a substrate, and B is a thickness (m) of a side end of the sealing layer after curing.

3. The encapsulating composition according to claim 1, wherein the curable compound having a cyclic structure comprises at least one or more curable functional groups.

4. The encapsulating composition according to claim 3, wherein the curable functional group is one or more selected from the group consisting of a glycidyl group, an isocyanate group, a hydroxyl group, a carboxyl group, an amide group, an epoxide group, a sulfide group, an acetal group and a lactone group.

5. The encapsulating composition according to claim 1, wherein the curable compound having a cyclic structure in its molecular structure has ring constituent atoms in the molecular structure in a range of 3 to 10.

6. The encapsulating composition according to claim 1, wherein the curable compound having a cyclic structure in its molecular structure is comprised in an amount of 25 to 145 parts by weight relative to 100 parts by weight of the vinyl ether curable compound.

7. The encapsulating composition according to claim 1, further comprising a curable compound having an oxetane group.

8. The encapsulating composition according to claim 7, wherein the curable compound having an oxetane group has bifunctionality or more.

9. The encapsulating composition according to claim 7, wherein the curable compound having an oxetane group is comprised in an amount of 5 to 90 parts by weight relative to 100 parts by weight of the vinyl ether curable compound.

10. The encapsulating composition according to claim 1, further comprising a surfactant.

11. The encapsulating composition according to claim 10, wherein the surfactant comprises a polar functional group.

12. The encapsulating composition according to claim 10, wherein the surfactant comprises a fluorine-based compound.

13. The encapsulating composition according to claim 10, wherein the surfactant is comprised in an amount of 0.01 parts by weight to 10 parts by weight relative to 100 parts by weight of the entire curable compound in the composition.

14. The encapsulating composition according to claim 1, further comprising a photoinitiator.

15. The encapsulating composition according to claim 14, wherein the photoinitiator is comprised in an amount of 1 to 15 parts by weight relative to 100 parts by weight of the entire curable compound in the composition.

16. The encapsulating composition according to claim 1, wherein the encapsulating composition is a solventless type ink composition.

17. An organic electronic device comprising a substrate; an organic electronic element formed on the substrate; and an organic layer sealing the entire surface of the organic electronic element and comprising the encapsulating composition according to claim 1.

18. A method for manufacturing an organic electronic device comprising a step of forming an organic layer on a substrate in which an organic electronic element is formed on its upper part, so that the encapsulating composition of claim 1 seals the entire surface of the organic electronic element.

19. The method for manufacturing an organic electronic device according to claim 18, wherein the step of forming an organic layer comprises inkjet printing, gravure coating or reverse offset coating.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIGS. 1 and 2 are cross-sectional views showing an organic electronic device according to one example of the present invention.

EXPLANATION OF REFERENCE NUMERALS

(2) 3: organic electronic device 31: substrate 32: organic electronic element 33: organic layer 34: inorganic layer 35: protective layer 36: sealing structure 37: encapsulation layer 38: cover substrate

BEST MODE

(3) Hereinafter, the present invention will be described in more detail through Examples according to the present invention and Comparative Examples not complying with the present invention, but the scope of the present invention is not limited by the following examples.

(4) Hereinafter, in Examples and Comparative Examples, alicyclic epoxy compounds, Celloxide 2021P (hereinafter, CEL2021P) and limonene dioxide (LDO) from Daicel, were used as curable compounds having a cyclic structure. As a vinyl ether curable compound, 1,4-cyclohexanedimethanol divinyl ether (CHDVE) was used. As oxetane group-containing curable compounds, OXT-221, 3-(allyloxy)oxetane and 3-ethyl-3 [(2-ethylhexyloxy)methyl]oxetane from TOAGOSEI were used. Also, TTA UV-694 (hereinafter, UV694), an iodonium salt photoinitiator from Tetrachem, was used as a photoinitiator, and F430 from DIC, a fluorine-based surfactant, was used as a surfactant. Furthermore, a silane coupling agent (KBM-403) was used as a coupling agent and 2-isopropylthioxanthone (ITX) was used as a photosensitizer. In addition, 2,6-di-tert-butyl-p-cresol (BHT from SIGMA aldrich) was used as a heat stabilizer.

Examples 1 to 8

(5) The above compositions were formulated in weight ratios as in Table 1 below, and introduced into a mixing vessel.

(6) In the mixing vessel, uniform encapsulating composition inks were prepared using a planetary mixer (Kurabo, KK-250s).

Comparative Examples 1 to 4

(7) The above compositions were formulated in weight ratios as in Table 2 below, and introduced into a mixing vessel. The unit is part by weight.

(8) In the mixing vessel, uniform encapsulating composition inks were prepared using a planetary mixer (Kurabo, KK-250s).

(9) TABLE-US-00001 TABLE 1 Example 1 2 3 4 5 6 7 8 LDO 10 30 20 10 10 10 10 5 CEL2021P 10 10 10 10 10 10 10 5 CHDVE 55 30 40 50 65 55 50 30 3-(allyloxy)- 17 oxetane 3-ethyl-3[(2- 22 ethylhexyloxy)- methyl]oxetane OXT-221 17 22 22 22 7 52 UV694 1 1 1 1 1 1 1 1 F430 1 1 1 1 1 1 1 1 KBM-403 5 5 5 5 5 5 5 5 ITX 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 BHT 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5

(10) TABLE-US-00002 TABLE 2 Comparative Example 1 2 3 4 LDO 92 CEL2021P 92 CHDVE 92 OXT-221 92 UV694 1 1 1 1 F430 1 1 1 1 KBM-403 5 5 5 5 ITX 0.5 0.5 0.5 0.5 BHT 0.5 0.5 0.5 0.5

(11) Physical properties in Examples and Comparative Examples were evaluated in the following manner.

(12) 1. Horn Step Measurement

(13) The encapsulating compositions prepared in Examples and Comparative Examples are each coated on a substrate to a thickness of about 50 m and UV-cured at an intensity of 1000 mW/cm.sup.2 through a light quantity of 4000 mJ/cm.sup.2 to form a sealing layer. Using an Alpha step (KLA-Tencor) instrument, the thickness A of the sealing layer is measured, and at the same time, the thickest area of the edge side end of the sealing layer is measured as the thickness B. At this time, by calculating by (BA)/A100, it is determined how much the horn step has occurred relative to the thickness of the sealing layer. When the horn step is 20% or less, it is classified as a good level.

(14) 2. Curing Sensitivity Measurement

(15) The encapsulating compositions prepared in Examples and Comparative Examples were each irradiated with UV of 1 J/cm.sup.2 at an intensity of 1000 mW/cm.sup.2 and then the tack free time of each adhesive was measured. First, the encapsulating composition is applied by spin coating to a thickness of 10 m and cured. A time until a tacky feeling disappears and there is no leakage of the sealing material when the surface of the sealing material has been touched immediately after curing, is defined as a tack free time and measured. It was classified as in the case where the tack free time was less than 1 second, as O in the case where it was less than 1 minute, as in the case where it was 5 minutes or more and as X in the case where it was 30 minutes or more.

(16) 3. Outgas Measurement

(17) The encapsulating compositions prepared in Examples and Comparative Examples were each cured by irradiation with UV of 1 J/cm.sup.2 at an intensity of 1000 mW/cm.sup.2, and 50 mg of each sample of the cured products was maintained at 110 C. for 30 minutes using Purge & Trap-gas chromatography/mass spectrometry and then the amount of volatile organic compounds was measured. The measurement was performed using a Purge & Trap sampler (JAI JTD-505 III)-GC/MS (Agilent 7890b/5977a) instrument. It was represented as in the case where the measured amount was less than 50 ppm, as O in the case where it was 100 ppm or less and as X in the case where it was more than 100 ppm.

(18) 4. Dark Spot

(19) The ink compositions prepared in Examples and Comparative Examples were each ink-jetted on a substrate, on which an organic electronic element was formed, by using Unijet UJ-200 (Inkjet head-Dimatix 10Pl 256) to form an organic layer having a pattern size of 110 cm and a thickness of 10 m. The applied ink composition was heat-treated at 100 C. for 3 minutes using a hot plate. The ink composition was cured by irradiation with UV of 1 J/cm.sup.2 at a wavelength of 395 nm and an intensity of 1000 mW/cm.sup.2 under a condition of 5% relative humidity to produce an organic electronic device.

(20) The produced organic electronic device is observed for dark spots under constant temperature and humidity conditions of 85 C. and 85% RH. It is checked whether or not dark spots are generated by observing it for 300 hours. It was classified as in the case where no dark spot was generated, as O in the case where one or less dark spot was generated, as A in the case where five or less dark spots were generated and as X in the case where more than five dark spots were observed.

(21) TABLE-US-00003 TABLE 3 Horn step Curing (%) sensitivity Outgas Dark spot Example 1 9 2 8 3 8 4 7 5 7 6 10 7 9 8 7 Comparative 1 8 X X X Example 2 30 X 3 9 X X 4 22 X