Method for preparing organic electronic device

Abstract

Provided is a method for preparing an organic electronic device, comprising steps of: applying an ink composition on a substrate, on which an organic electronic element is formed; applying heat thereto before curing the applied ink composition; and curing the applied ink composition by irradiating with light having a wavelength in a range of 300 nm to 450 nm. Also provided is 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, wherein after the organic layer is maintained at 110° C. for 30 minutes, the out-gas amount measured using Purge & Trap-gas chromatography/mass spectrometry is less than 150 ppm.

Claims

1. A method for preparing an organic electronic device, comprising steps of: applying an ink composition on a substrate, on which an organic electronic element is formed; applying heat thereto before curing the applied ink composition; curing the applied ink composition by irradiating with light having a wavelength in a range of 300 nm to 450 nm, and applying heat after curing at a temperature in a range of 20° C. to 230° C. for 1 minute to 40 minutes.

2. The method according to claim 1, wherein the step of applying heat before curing proceeds at a temperature in a range of 20° C. to 110° C., and the step of applying heat after curing proceeds at a temperature in a range of 50° C. to 230° C.

3. The method according to claim 1, wherein the ratio (T2/T1) of the temperature (T2) for applying heat after curing to the temperature (T1) for applying heat before curing is in a range of 1.15 to 8.

4. The method according to claim 1, further comprising a step of planarizing the applied ink composition before curing.

5. The method according to claim 4, wherein the step of the planarizing proceeds for one time from 1 minute to 5 minutes.

6. The method according to claim 1, wherein the step of applying an ink composition comprises ejecting the ink composition using an inkjet apparatus.

7. The method according to claim 1, wherein the ink composition is a solventless type.

8. The method according to claim 1, wherein the ink composition is a photocurable composition.

9. The method according to claim 1, wherein after the applied ink composition is maintained at 110° C. for 30 minutes after curing, the out-gas amount measured using Purge & Trap-gas chromatography/mass spectrometry is less than 150 ppm.

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

(3) 31: substrate

(4) 32: organic electronic element

(5) 33: organic layer

(6) 34: inorganic layer

(7) 35: inorganic protective layer

(8) 36: sealing structure

(9) 37: sealing film

(10) 38: cover substrate

Detailed Description

(11) 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.

(12) Preparation of Ink Composition

(13) An alicyclic epoxy compound (Celloxide 2021P, Daicel Corp.) and an aliphatic epoxy compound (DE200, HAJIN CHEM TECH) as epoxy compounds, an oxetane group-containing compound (OXT-221 from TOAGOSEI), a photoinitiator comprising an iodonium salt (TTA-UV694 from Tetrachem, hereinafter, UV694) and a fluorine-based surfactant (F552 from DIC) were introduced into a mixing vessel in a weight ratio of 23.8:28.7:37.5:5.0:1.0 (Celloxide2021P: DE200: OXT-221: UV694: F552), respectively, at room temperature.

(14) In the mixing vessel, a uniform ink composition was prepared using a planetary mixer (Kurabo, KK-250s).

EXAMPLE 1

(15) The prepared ink composition was subjected to ink jetting on a substrate, on which an organic electronic element was formed, using Unijet UJ-200 (Inkjet head-Dimatix 10Pl 256) to form an organic layer having a pattern size of 1×10 cm and a thickness of 10 μm. The applied ink composition was subjected to heat treatment at 100° C. for 3 minutes using a hot plate. The ink composition was irradiated with UV of 1 J/cm.sup.2 having a wavelength of 395 nm and an intensity of 1000 mW/cm.sup.2 under a 5% relative humidity condition and cured to prepare an organic electronic device.

EXAMPLE 2

(16) An organic electronic device was prepared in the same manner as in Example 1, except that the applied ink composition was subjected to heat treatment at 25° C. for 3 minutes, and further heat treatment at 60° C. for 30 minutes after curing.

(17) EXAMPLE 3

(18) An organic electronic device was prepared in the same manner as in Example 1, except that the applied ink composition was subjected to heat treatment at 30° C. for 10 minutes, and further heat treatment at 150° C. for 3 minutes after curing.

EXAMPLE 4

(19) An organic electronic device was prepared in the same manner as in Example 1, except that the applied ink composition was subjected to heat treatment at 25° C. for 3 minutes before curing.

EXAMPLE 5

(20) An organic electronic device was prepared in the same manner as in Example 1, except that the applied ink composition was subjected to heat treatment at 60° C. for 10 minutes, and further heat treatment at 200° C. for 10 minutes after curing.

EXAMPLE 6

(21) An organic electronic device was prepared in the same manner as in Example 1, except that the applied ink composition was subjected to heat treatment at 30° C. for 10 minutes, and further heat treatment at 120° C. for 90 minutes after curing.

COMPARATIVE EXAMPLE 1

(22) An organic electronic device was prepared in the same manner as in Example 1, except that no heat treatment was performed.

COMPARATIVE EXAMPLE 2

(23) An organic electronic device was prepared in the same manner as in Example 1, except that no heat treatment was performed before curing, and the heat treatment proceeded at 150° C. for 3 minutes after curing.

COMPARATIVE EXAMPLE 3

(24) An organic electronic device was prepared in the same manner as in Example 3, except that in the curing step, it was irradiated with UV of 1 J/cm.sup.2 having a wavelength range of 255 nm and an intensity of 1000 mW/cm.sup.2 under a 5% relative humidity condition and cured to prepare an organic electronic device.

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

(26) 1. Pattern Step Measurement and Flatness Measurement

(27) The thickness A of the central part of the pattern is measured for each organic layer pattern formed in Examples and Comparative Examples, and at the same time, the thickest region of the edge side of the pattern was measured as the thickness B. At this time, it was measured what extent the pattern step had occurred relative to the pattern thicknesses by calculating them as (B-A)/A×100. It was classified as excellent in the case where the step was 10% or less, good in the case where it was 20% or less, and poor in the case where it was more than 20%.

(28) 2. Out-Gas MEASUREMENT

(29) The cured ink compositions of Examples and Comparative Examples were maintained at 110° C. for 30 minutes and their out-gas amounts were measured by using a Purge & Trap sampler (JAI JTD-505III)-GC/MS (Agilent 7890b/5977a) instrument with Purge &Trap-gas chromatography/mass spectrometry. It was classified as ⊚ in the case where it was less than 50 ppm, 0 in the case where it was less than 100 ppm, Δ in the case where it was less than 150 ppm, and X in the case where it was 150 ppm or more.

(30) 3. Dark Spot

(31) The organic electronic devices prepared in Examples and Comparative Examples were observed for dark spots under constant temperature and humidity conditions at 85° C. and 85% RH. It was checked if there are no dark spots generated by observing them for 300 hours. It was classified as ⊚ in the case where no dark spot occurred, O in the case where one or less of dark spot occurred, Δ in the case where 5 or less of dark spots occurred, and X in the case where more than 5 of dark spots occurred.

(32) TABLE-US-00001 TABLE 1 Pattern Dark Step (%) Flatness Out-gas Spot Example 1 7.5 Excellent ◯ ◯ Example 2 16.7 Good ⊚ ◯ Example 3 8.1 Excellent ⊚ ⊚ Example 4 19.2 Good Δ Δ Example 5 7.8 Excellent ◯ Δ Example 6 8.1 Excellent Δ Δ Comparative 34.9 Poor X X Example 1 Comparative 29.4 Poor ◯ Δ Example 2 Comparative Not measurable Not measurable Not measurable X Example 3 (Poor curing) (Poor curing) (Poor curing)