Pattern formation method for electroluminescent element

• US 8,267,735 B2
• Filed: 01/26/2010
• Issued: 09/18/2012
• Est. Priority Date: 07/31/2002
• Status: Expired due to Fees

• Current Assignee: Dai Nippon Printing Company Limited
• Original Assignee: Dai Nippon Printing Company Limited
• Inventors: Ito, Nobuyuki, Ito, Norihito
• Primary Examiner(s): HINES, ANNE M
• Application Number:
  US12/693,822
• Publication Number:
  US 20100124603A1
• Time in Patent Office: 966 Days
• Field of Search: 313504-512, 445 24- 25
• US Class Current: 445/24
• CPC Class Codes: H10K 59/122 Pixel-defining structures or layers, e.g. banks
• CPC Class Codes: H10K 71/135 using ink-jet printing
• CPC Class Codes: H10K 85/1135 Polyethylene dioxythiophene [PEDOT]; Derivatives thereof
• CPC Class Codes: H10K 85/146 poly N-vinylcarbazol; Derivatives thereof
• CPC Class Codes: H10K 85/60 Organic compounds having low molecular weight H10K85/10 - H10K85/50 take precedence
• CPC Class Codes: H10K 85/615 Polycyclic condensed aromatic hydrocarbons, e.g. anthracene
• CPC Class Codes: Y10S 428/917 Electroluminescent
• CPC Class Codes: Y10T 428/24777 Edge feature

Abstract

There is provided a pattern formed object having an electroluminescent layer coating. The pattern formed object comprising a substrate, partition walls provided on the substrate, and a coating stacked on the substrate in its part between the partition walls, wherein the partition walls have a sloped liquid non-repellent surface and have a section form that, at least in the lower part of the partition wall, as the distance from the substrate increases, the size of the partition wall in a direction parallel to the substrate decreases, and in the coating, the ratio of the maximum thickness (Tmax) to the minimum thickness (Tmin), Tmax/Tmin, is not more than 130% as measured in the coating in its part between the lower ends of the partition walls adjacent to each other.

Claims

1. A method for pattern formation, comprising the steps of:

preparing a substrate on which electrodes are provided with a space between the electrodes;

forming, on the substrate on which the electrodes are provided in the space between the electrodes, partition walls which have a liquid-nonrepellent surface and have such a sectional form that, at least in the lower part of the partition wall, as the distance from the substrate increases, the size of the partition wall in a direction parallel to the substrate decreases, and the size of the partition walls in its part provided on the electrode in a direction parallel to the substrate is not less than 1 μ

m;

applying a coating comprising an EL light emitting layer on an upper surface of the electrodes provided on the substrate in its part between the partition walls;

forming the EL light emitting layer by one of a dispenser method and an ink jet method; and

drying and solidifying the coating to form a solidified coating of which the ratio of the maximum thickness (Tmax) to the minimum thickness (Tmin), Tmax/Tmin, is not more than 130% as measured in the coating in its part between the lower ends of the partition walls adjacent to each other.

2. The method for pattern formation according to claim 1, wherein said partition wall is formed by forming a lower partition wall structure, which is provided on the substrate side and is in the form of a trapezoid, in section, with the long side being located on the substrate side, and then forming an upper partition wall structure provided on the lower partition wall structure.

3. A method for pattern formation for an electroluminescent element, comprising the steps of:

forming a first electrode on a substrate;

forming partition walls according to the method as defined in claim 1;

forming a coating as an EL light emitting layer using a coating liquid for EL light emitting layer formation according to the method as defined in claim 1;

and

forming a second electrode on the EL light emitting layer.

4. The method for pattern formation for an electroluminescent element according to claim 3, wherein the coating liquid for EL light emitting layer formation is applied by a dispenser method or an ink jet method.

5. The method for pattern formation for an electroluminescent element according to claim 4, wherein, prior to the formation of the EL light emitting layer, a hole injection layer is formed in a space between the partition walls adjacent to each other.

6. The method for pattern formation for an electroluminescent element according to claim 4, wherein, prior to the formation of the EL light emitting layer, a hole injection layer is formed on the whole area of the assembly including the upper surface of the partition walls.

7. The method for pattern formation for an electroluminescent element according to claim 3, wherein, prior to the formation of the EL light emitting layer, a hole injection layer is formed in a space between the partition walls adjacent to each other.

8. The method for pattern formation for an electroluminescent element according to claim 3, wherein, prior to the formation of the EL light emitting layer, a hole injection layer is formed on the whole area of the assembly including the upper surface of the partition walls.