Electroluminescent light element having a transparent electrode formed by a paste material which provides uniform illumination

• US 5,844,362 A
• Filed: 07/12/1996
• Issued: 12/01/1998
• Est. Priority Date: 07/14/1995
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Ikoma, Heiji, Tanabe, Koji, Ohara, Masahiro, Chikahisa, Yosuke, Kuwahara, Masaru
• Primary Examiner(s): O'Shea, Sandra
• Assistant Examiner(s): Gerike, Matthew J.
• Application Number:
  US08/679,091
• Time in Patent Office: 872 Days
• Field of Search: 313/506, 313/509, 313/511, 313/512, 178/18, 248/690, 257/103, 428/690, 372/45
• US Class Current: 313/506
• CPC Class Codes: H01H 13/702 with contacts carried by or formed from layers in a multilayer structure, e.g. membrane switches
• CPC Class Codes: H01H 2219/018 Electroluminescent panel
• CPC Class Codes: H01H 2219/028 Printed information
• CPC Class Codes: H01H 2219/046 above switch site
• CPC Class Codes: H01H 2221/05 Force concentrator; Actuating dimple
• CPC Class Codes: H05B 33/00 Electroluminescent light sources
• CPC Class Codes: H05B 33/10 Apparatus or processes specially adapted to the manufacture of electroluminescent light sources
• CPC Class Codes: H05B 33/12 Light sources with substantially two-dimensional radiating surfaces
• CPC Class Codes: H05B 33/28 of translucent electrodes
• CPC Class Codes: H10K 2102/102 comprising tin oxides, e.g. fluorine-doped SnO2
• CPC Class Codes: H10K 50/81 Anodes
• CPC Class Codes: H10K 59/8051 Anodes
• CPC Class Codes: H10K 59/8723 Vertical spacers, e.g. arranged between the sealing arrangement and the OLED

Abstract

All of a transparent electrode layer 2, a light-emitting layer 3, a dielectric layer 4, a back-surface electrode 5, collecting electrodes 5a, 5b, and an insulating coat layer 6 are laminated with predetermined patterns by screen printing on an insulating transparent film 1. Conductive paste used for forming transparent electrode layer 2 comprises conductive powder of indium oxide which contains needle-like powder (A) and fine-gain powder (B) at a blending ratio of (A):(B)=100:0 to 20:80. A binder resin (D), being a photo-hardening or thermal-hardening resin, is mixed with the conductive powder (C) at a blending ratio of (C):(D)=45:55 to 95:5, thereby obtaining an excellent EL lighting element.

Claims

1. An electroluminescent lighting element comprising:

an insulating transparent film serving as a base material integrally formed with an external connecting terminal;

a transparent electrode layer of a predetermined pattern printed on a surface of said insulating transparent film other than said external connecting terminal to define a predetermined light-emitting region being offset from said external connecting terminal;

a light-emitting layer of a predetermined pattern printed on said transparent electrode layer as a light-emitting member corresponding to said light-emitting region;

a dielectric layer of a predetermined pattern printed on said light-emitting layer;

a back-surface electrode layer of a predetermined pattern printed on said dielectric layer;

a first collecting electrode layer printed in a predetermined pattern having one end connected to said back-surface electrode layer and the other end constituting part of said external connecting terminal of said insulating transparent film;

a second collecting electrode layer printed in a predetermined pattern having one end connected to said transparent electrode layer and the other end constituting part of said external connecting terminal of said insulating transparent film; and

an insulating coat layer printed in a predetermined pattern so as to cover a surface of said electroluminescent lighting element except for said external connecting terminal.

2. The electroluminescent lighting element in accordance with claim 1, wherein said transparent electrode layer is formed by using a paste including conductive powder having light permeability which is diffused in an insulating resin or in a solution containing insulating resin, said conductive powder is indium oxide powder, and said insulating resin is photo-hardening or thermal-hardening resin.

3. The electroluminescent lighting element in accordance with claim 2, wherein said indium oxide powder serving as said conductive powder comprises needle-like powder (A) and fine-grain powder (B) blended at a weight ratio (A):

(B) somewhere in a range of 100;

0 to 20;

80, and all the conductive powder (C) is blended with the insulating resin (D) at a weight ratio (C);

(D) somewhere in a range of 45;

55 to 95;

5.

4. The electroluminescent lighting element in accordance with claim 2, wherein said insulating resin diffusing said light-permeable conductive powder therein is acrylate group photo-hardening resin, or thermal-hardening resin containing at least one selected from the group consisting of epoxy resin, urethane modified epoxy resin, epoxy modified polyester resin.

5. The electroluminescent lighting element in accordance with claim 1, wherein an anisotropic conductive adhesive is applied on said first and second collecting electrodes of a distal end of said external connecting terminal.

6. The electroluminescent lighting element in accordance with claim 1, wherein a reinforcement board is provided on a reverse surface of said insulating transparent film in a region of said other ends of said first and second collecting electrodes constituting said external connecting terminal.