Thermal transfer element and process for forming organic electroluminescent devices

• US 6,291,126 B2
• Filed: 12/01/2000
• Issued: 09/18/2001
• Est. Priority Date: 01/15/1999
• Status: Expired due to Term

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: McCormick, Fred B., Hsu, Yong, Wolk, Martin B., Baude, Paul F.
• Primary Examiner(s): Schilling, Richard L.
• Application Number:
  US09/728,924
• Publication Number:
  US 20010000744A1
• Time in Patent Office: 291 Days
• Field of Search: 430/200, 430/312, 430/319, 156/234, 427/592, 427/66
• US Class Current: 430/200
• CPC Class Codes: B41M 3/006 Patterns of chemical products used for a specific purpose, e.g. pesticides, perfumes, adhesive patterns; use of microencapsulated material; Printing on smoking articles
• CPC Class Codes: B41M 5/265 for the production of optical filters or electrical components
• CPC Class Codes: B41M 5/38207 characterised by aspects not provided for in groups B41M5/385 - B41M5/395
• CPC Class Codes: B41M 5/38214 Structural details, e.g. multilayer systems composition of individual layers B41M5/42
• CPC Class Codes: B41M 5/392 Additives, other than colour forming substances, dyes or pigments, e.g. sensitisers, transfer promoting agents
• CPC Class Codes: B41M 5/395 Macromolecular additives, e.g. binders
• CPC Class Codes: B41M 5/42 Intermediate, backcoat, or covering layers B41M5/405 takes precedence; multilayer thermal transfer systems in general B41M5/38214
• CPC Class Codes: G02B 6/1221 made from organic materials
• CPC Class Codes: G02B 6/138 by using polymerisation
• CPC Class Codes: H05B 33/10 Apparatus or processes specially adapted to the manufacture of electroluminescent light sources
• CPC Class Codes: H05K 3/046 by selective transfer or selective detachment of a conductive layer
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 59/122 Pixel-defining structures or layers, e.g. banks
• CPC Class Codes: H10K 59/173 comprising banks or shadow masks
• CPC Class Codes: H10K 71/00 Manufacture or treatment specially adapted for the organic devices covered by this subclass
• CPC Class Codes: H10K 71/10 Deposition of organic active material
• CPC Class Codes: H10K 71/13 using printing techniques, e.g. ink-jet printing or screen printing
• CPC Class Codes: H10K 71/18 using non-liquid printing techniques, e.g. thermal transfer printing from a donor sheet
• CPC Class Codes: H10K 71/40 Thermal treatment, e.g. annealing in the presence of a solvent vapour
• CPC Class Codes: H10K 85/115 Polyfluorene; Derivatives thereof
• CPC Class Codes: Y10S 430/165 : Thermal imaging composition

Abstract

Disclosed are thermal transfer elements and processes for patterning organic materials for electronic devices onto patterned substrates. These donor elements and methods are particularly suited for making organic electroluminescent devices and displays. The donor elements can include a substrate, and optional light-to-heat conversion layer, and a single or multicomponent transfer layer that can be imagewise transferred to a receptor to form an organic electroluminescent device, portions thereof, or components therefor, The methods offer advantages over conventional patterning techniques such as photolithography, and make it possible to fabricate new organic electroluminescent device constructions.

Claims

1. A method for making an organic electroluminescent device comprising the steps of:

providing a receptor substrate that includes an electrode and a pattern of spaced insulators on the electrode that leaves at least a portion of the electrode exposed; and

selectively thermally transferring an organic light emitting material from a thermal transfer donor element to the receptor to cover at least a portion of the exposed electrode.

2. The method of claim 1, wherein the thermal transfer donor element comprises a substrate, a light-to-heat conversion layer disposed on the substrate, an interlayer disposed on the light-to-heat conversion layer, and a thermal transfer layer disposed on the interlayer, the transfer layer comprising the organic light emitting material.

3. The method of claim 2, wherein the thermal transfer layer further comprises a charge transport layer.

4. The method of claim 2, wherein the thermal transfer layer further comprises a counter-electrode layer.

5. The method of claim 1, further comprising thermally transferring a charge transport material between the organic light emitting material and the receptor.

6. The method of claim 1, further comprising disposing a counter-electrode over the organic light emitting material after the thermally transferring step.

7. The method of claim 1, wherein the organic light emitting material comprises a light emitting polymer.

8. The method of claim 1, wherein the organic light emitting material comprises an organic small molecule material.

9. The method of claim 1, wherein the step of thermally transferring comprises selectively heating the donor element using a thermal print head.

10. The method of claim 1, wherein the step of thermally transferring comprises selectively exposing the donor element to imaging radiation, the donor element including a radiation absorber for converting the imaging radiation into heat.

11. The method of claim 1, wherein the receptor comprises glass.

12. The method of claim 1, wherein the receptor is flexible.

13. The method of claim 1, wherein the electrode is a transparent electrode.

14. The method of claim 1, wherein the electrode includes a conductor disposed between the receptor substrate and an organic charge transport material.