Patent EP0468438A2 successfully refreshed from Google Patents.
EP0468438A2
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Organic electroluminescent device with stabilizing fused metal particle cathode
Assignee: Eastman Kodak Co
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Filing: 1991-07-23
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Granted: —
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Expires: 2011-07-23
Abstract
Abstract An organic electroluminescent device (100) is disclosed which is protected from dark spot formation. The device (100) is comprised of, in sequence, a support (102), an anode (104), an organic electroluminescent medium (106), and a cathode (118). The cathode (118) is comprised of an electron injecting layer (120) contacting the organic electroluminescent medium (106) containing a plurality of metals at least one of which has a work function of less than that of indium. The cathode (118) is comprised of a layer of fused metal particles containing at least 80 percent indium and having a mean diameter of less than 1 mu m and a coefficient of variation of less than 20 percent. <IMAGE>
Inventors
- 👤 Michael C/O Eastman Kodak Company Scozzafava
- 👤 Ching Wan C/O Eastman Kodak Company Tang
- 👤 Jon Eric C/O Eastman Kodak Company Littman
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-25 14:43
CPC Classifications
H; H05; H05B; H05B33/00; H05B33/12; H05B33/26; H01; H01B; H01B1/00; H01B1/02; H05B33/14; H10; H10K; H10K50/00; H10K50/80; H10K50/805; H10K50/82; H10K50/826; Y; Y10; Y10S; Y10S428/00; Y10S428/917; Y10T; Y10T428/00; Y10T428/25; Y10T428/258
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
85 words
An organic electroluminescent device comprised of, in sequence, a support, an anode, an organic electroluminescent medium, and a cathode consisting essentially of a plurality of metals other than alkali metals, at least one of said metals having a work function less than that of indium, characterized in that said cathode is comprised of a layer of fused metal particles containing at least 80 percent indium and having a mean diameter of less than 1 µm and a coefficient of variation of less than 20 percent.
Claim 2
Dependent Claim
85 words
An organic electroluminescent device comprised of, in sequence, a support, an anode, an organic electroluminescent medium, and a cathode consisting essentially of a plurality of metals other than alkali metals, at least one of said metals having a work function less than that of indium, characterized in that said cathode is comprised of a layer of fused metal particles containing at least 80 percent indium and having a mean diameter of less than 1 µm and a coefficient of variation of less than 20 percent.
Claim 3
Dependent Claim
22 words
An electroluminescent device according to claim 1 further characterized in that indium constitutes at least 90 percent of said fused metal particles.
Claim 4
Dependent Claim
26 words
An electroluminescent device according to claim 1 or 2 further characterized in that said layer of fused metal particles has a thickness of at least 1000Å.
Claim 5
Dependent Claim
52 words
An organic electroluminescent device according to any one of claims 1 to 3 inclusive further characterized in that said layer of fused metal particles is positioned in contact with said organic electroluminescent medium and said fused metal particles include at least one metal having a work function less than that of indium.
Claim 6
Dependent Claim
46 words
An organic electroluminescent device according to any one of claims 1 to 4 inclusive further characterized in that indium is present in said fused metal particles in combination with one or more metals each of which have a work function ranging from 3.8 to 3.0 eV.
Claim 7
Dependent Claim
30 words
An organic electroluminescent device according to claim 5 further characterized in that said one or more metals have a work function in the range of from 3.8 to 3.5 eV.
Claim 8
Dependent Claim
39 words
An organic electroluminescent device according to any one of claims 1 to 6 inclusive further characterized in that said metal having a work function less than that of indium is present in a concentration of at least 0.05 percent.
Claim 9
Dependent Claim
39 words
An organic electroluminescent device according to any one of claims 1 to 7 inclusive further characterized in that said metal having a work function less than that of indium is present in a concentration of at least 0.1 percent.
Claim 10
Dependent Claim
31 words
An organic electroluminescent device according to any one of claims 1 to 8 inclusive further characterized in that said metal having a work function less than that of indium is magnesium.
Claim 11
Dependent Claim
34 words
An organic electroluminescent device according to any one of claims 1 to 9 inclusive further characterized in that said organic electroluminescent medium is comprised of an electron injecting and transporting zone contacting said cathode.
Claim 12
Dependent Claim
26 words
An organic electroluminescent device according to claim 10 further characterized in that electron injecting and transporting zone is comprised of a stilbene or chelated oxinoid compound.
Claim 13
Dependent Claim
54 words
An organic electroluminescent device according to claim 11 further characterized in that said chelated oxinoid comound is represented by the formula: wherein Me represents a metal; n is an integer of from 1 to 3; and Z independently in each occurrence represents the atoms completing a nucleus having at least two fused aromatic rings.
Claim 14
Dependent Claim
63 words
An organic electroluminescent device according to any one of claims 1 to 12 inclusive further characterized in that said cathode is comprised of an electron injecting layer contacting said organic electroluminescent medium containing at least one metal having a work function less than that of indium and said fused metal particle layer forms a capping layer of said cathode overlying said injecting layer.
Claim 15
Dependent Claim
21 words
An organic electroluminescent device according to claim 13 further characterized in that said fused metal particle layer consists essentially of indium.
Claim 16
Dependent Claim
33 words
An organic electroluminescent device according to claim 13 further characterized in that said electron injecting layer consists essentially of magnesium and at least one other metal having a higher work function than magnesium.
Claim 17
Dependent Claim
28 words
An organic electroluminescent device according to claim 15 further characterized in that said electron injecting layer consists essentially of magnesium and at least one of silver and aluminum.
Claim 18
Dependent Claim
41 words
An organic electroluminescent device according to claim 13 further characterized in that said electron injecting layer consists essentially of fused metal particles comprised of at least 80 percent indium and at least one metal having a lower work function than indium.
Claim 19
Dependent Claim
35 words
An organic electroluminescent device according to claim 17 further characterized in that said electron injecting layer consists essentially of fused metal particles comprised of at least 90 percent indium and at least 0.1 percent magnesium.
References Cited (Backward Citations)
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