Electroluminescent element and method for fabricating the same

• US 5,882,806 A
• Filed: 08/11/1995
• Issued: 03/16/1999
• Est. Priority Date: 08/12/1994
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Mori, Naoyuki
• Primary Examiner(s): NOLD, CHARLES R
• Application Number:
  US08/514,087
• Time in Patent Office: 1,313 Days
• Field of Search: 428/690, 428/917, 428/421, 428/691, 313/504
• US Class Current: 428/690
• CPC Class Codes: H05B 33/12 Light sources with substantially two-dimensional radiating surfaces
• CPC Class Codes: H05B 33/145 Arrangements of the electroluminescent material
• CPC Class Codes: H05B 33/20 characterised by the chemical or physical composition or the arrangement of the material in which the electroluminescent material is embedded
• CPC Class Codes: Y10S 428/917 Electroluminescent
• CPC Class Codes: Y10T 428/3154 Of fluorinated addition polymer from unsaturated monomers

Abstract

An electroluminescent element is disclosed in which a luminescent layer is formed on a reflective insulating layer coated on a back electrode. The luminescent layer is made of moisture-proof coated phosphor powder distributed in a fluorinated resin such that the phosphor powder is entirely covered with the fluorinated resin. A transparent electrode is bonded to a top surface of the luminescent layer where the phosphor particles are not exposed.

Claims

1. An electroluminescent element comprising:

a back electrode;

a reflective insulating layer formed on said back electrode;

a luminescent layer formed on said reflective insulating layer, said luminescent layer including a phosphor powder dispersed in fluorinated rubber, a mixing weight ratio of said phosphor powder to said fluorinated rubber being in a range of 1;

1 to 5;

1; and

a transparent electrode formed on said luminescent layer, said phosphor powder being located in said luminescent layer toward said insulating layer, said phosphor powder being free from contact with said transparent electrode, thereby improving adhesion between said luminescent layer and said transparent electrode;

wherein said phosphor powder is located nearer to said reflective insulating layer than is said transparent electrode.

2. The electroluminescent element of claim 1, said reflective insulating layer further comprising an insulator powder dispersed in a fluorinated rubber.