# US 2014/0151648 A1 · Organic electroluminescenet device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0151648 A1 - Document ID: US20140151648A1 - Status: Published application - Kind: A1 - Application number: 13/892,868 - Filed: 2013-05-13 - Published: 2014-06-05 - Earliest claimed: 2002-03-26 - Assignees: Rohm Co., Ltd. - Applicants: Rohm Company, Ltd - Inventors: Junji Kido - Web page: https://patentgrep.com/patent/US20140151648A1 ## CPC - C07C 211/58: Naphthylamines; N-substituted derivatives thereof - C07C 211/61: with at least one of the condensed ring systems formed by three or more rings - C09K 11/06: containing organic luminescent materials - H10K 50/125: specially adapted for multicolour light emission, e.g. for emitting white light - H10K 50/131: {with spacer layers between the electroluminescent layers} - H10K 50/15: Hole transporting layers - H10K 50/16: Electron transporting layers - H10K 50/17: Carrier injection layers - H10K 50/171: {Electron injection layers} - H10K 50/19: Tandem OLEDs - C07C 2603/18: Fluorenes; Hydrogenated fluorenes - C09K 2211/1003: Carbocyclic compounds - C09K 2211/1007: Non-condensed systems - C09K 2211/1011: Condensed systems - C09K 2211/1014: bridged by heteroatoms, e.g. N, P, Si or B - H10K 59/875: {Arrangements for extracting light from the devices} - H10K 71/40: Thermal treatment, e.g. annealing in the presence of a solvent vapour - H10K 85/60: Organic compounds having low molecular weight (H10K85/10 - H10K85/50 take precedence) - H10K 85/624: {containing six or more rings} - H10K 85/626: {containing more than one polycyclic condensed aromatic rings, e.g. bis-anthracene} - H10K 85/633: {comprising polycyclic condensed aromatic hydrocarbons as substituents on the nitrogen atom} - Y10T 428/24942: including components having same physical characteristic in differing degree - C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract An organic electroluminescent device includes at least two light-emissive units provided between a cathode electrode and an anode electrode opposed to the cathode electrode, each of the light-emissive units including at least one light-emissive layer. The light-emissive units are partitioned from each other by at least one charge generation layer, the charge generation layer being an electrically insulating layer having a resistivity of not less than 1.0×102 Ωcm. ## Claims ### Claim 1 An organic electroluminescent device comprising: at least two light-emissive units provided between a cathode electrode and an anode electrode opposed to said cathode electrode, each of said light-emissive units including at least one light-emissive layer; wherein said light-emissive units are partitioned from each other by at least one charge generation layer, said charge generation layer constituting an electrically insulating layer having a resistivity of not less than 1.0×102 Ωcm. ### Claim 2 (depends on 1) The organic electroluminescent device according to claim 1, wherein the charge generation layer constitutes an electrically insulating layer having a resistivity of not less than 1.0×105 Ωcm. ### Claim 3 (depends on 1, 2) The organic electroluminescent device according to claim 1 or 2, wherein said charge generation layer comprises at least one of a laminated and mixed layer formed from two different materials; wherein a charge transfer complex including a radical cation and a radical anion is formed upon an oxidation-reduction reaction between said two materials, and a radical cation state and a radical anion state in said charge transfer complex is transferred to a direction of the cathode and a direction of the anode, respectively, when a voltage is applied to said device, so that a hole is injected into the light-emissive unit which is located on a cathode side of the charge generation layer and is adjacent thereto, and an electron is injected into the light-emissive unit which is located on an anode side of the charge generation layer and is adjacent thereto. ### Claim 4 (depends on 1) The organic electroluminescent device according to claim 1, wherein said charge generation layer comprises one of a laminated and a mixed layer comprising: an organic compound having an ionization potential of less than 5.7 eV and a hole transporting property or electron donating property; and one of an inorganic and organic material capable of forming a charge transfer complex through the oxidation-reduction reaction thereof with said organic compound; wherein said charge generation layer contains a charge transfer complex formed upon the oxidation-reduction reaction between said organic compound and one of an inorganic and organic material. ### Claim 5 (depends on 4) The organic electroluminescent device according to claim 4, wherein said organic compound comprises an arylamine compound, wherein said arylamine compound is represented by the following formula (I): wherein Ar1, Ar2 and Ar3 each independently represents an aromatic hydrocarbon group which may have substituents. ### Claim 6 (depends on 5) The organic electroluminescent device according to claim 5, wherein said organic compound comprises an arylamine compound having a glass transition temperature of not lower than 90° C. ### Claim 7 (depends on 6) The organic electroluminescent device according to claim 6, wherein said arylamine comprises one of α-NPD, 2-TNATA, spiro-TAD, and spiro-NPB. ### Claim 8 (depends on 4) The organic electroluminescent device according to claim 4, wherein said inorganic material comprises a metal oxide. ### Claim 9 (depends on 4) The organic electroluminescent device according to claim 4, wherein said inorganic material comprises a metal halide. ### Claim 10 (depends on 8) The organic electroluminescent device according to claim 8, wherein said metal oxide comprises one of vanadium pentaoxide and rhenium heptaoxide. ### Claim 11 (depends on 4) The organic electroluminescent device according to claim 4, wherein said inorganic material is deposited by one of a resistive heating vapor deposition method, an electron beam vapor deposition method and a laser beam vapor deposition method. ### Claim 12 (depends on 4) The organic electroluminescent device according to claim 4, wherein said inorganic material is deposited by a sputtering method; wherein a sputtering apparatus used in the sputtering method is a facing target sputtering system which comprises a pair of opposed targets provided at a certain distance, a reflection electrode capable of reflecting electrons towards a front peripheral area of each target, and a magnetic field generation device capable of forming a parallel magnetic field in the vicinity of the peripheral portion of each target, said magnetic field having a portion parallel to the peripheral portion of the target. ### Claim 13 (depends on 4) The organic electroluminescent device according to claim 4, wherein said organic material-comprises at least one fluorine as a substituent group, and possesses at least one of an electron injection property and an electron accepting property. ### Claim 14 (depends on 4) The organic electroluminescent device according to claim 4, wherein said organic material comprises at least one cyano group as a substituent group, and possesses at least one of an electron injection property and an electron accepting property. ### Claim 15 (depends on 13) The organic electroluminescent device according to claim 13, wherein said organic material comprises tetrafluoro-tetracyanoquinodimethane (4F-TCNQ). ### Claim 16 (depends on 1, 2) The organic electroluminescent device according to claim 1 or 2, wherein said light-emissive unit comprises, as a layer located on an anode side of said charge generation layer and being adjacent thereto, an electron injection layer having a mixture including an organic compound and a metal functioning as an electron donating dopant. ### Claim 17 (depends on 16) The organic electroluminescent device according to claim 16, wherein said electron donating dopant comprises at least one metal selected from a group including an alkaline metal, an alkaline earth metal and a rare earth metal. ### Claim 18 (depends on 17) The organic electroluminescent device according to claim 17, wherein said metal of the electron donating dopant is provided in a molar ratio of 0.1 to 10 with respect to said organic compound in said electron injection layer. ### Claim 19 (depends on 1, 2) The organic electroluminescent device according to claim 1 or 2, wherein said light-emissive unit comprises, as a layer located on an anode side of said charge generation layer and being adjacent thereto, a metal layer having a thickness of not more than 5 nm formed from a metal selected from an alkaline metal, an alkaline earth metal and a rare earth metal; wherein said metal constituting the layer diffuses in the adjacent electron transporting layer to react with electron transporting organic material; and wherein, as a result of said diffusion, an electron injection layer is composed of a mixture including said electron transporting organic material and a metal functioning as an electron donating dopant is formed. ### Claim 20 (depends on 1, 2) The organic electroluminescent device according to claim 1 or 2, wherein said light-emissive unit comprises, as a layer located on an anode side of said charge generation layer and being adjacent thereto, a layer including an organic metal complex compound including at least one metal ion selected from an alkaline metal ion, an alkaline earth metal ion and a rare earth metal ion, and a reaction generating layer which is formed by an in-situ reduction reaction when a thermally reducible metal, which can reduce a metal ion in said organic metal complex to a metal in a vacuum is deposited on the organic metal complex constituting the layer. ### Claim 21 (depends on 1, 2) The organic electroluminescent device according to claim 1 or 2, wherein said light-emissive unit comprises, as a layer located on an anode side of said charge generation layer and being adjacent thereto, a layer including an inorganic compound including at least one metal ion selected from an alkaline metal ion, an alkaline earth metal ion and a rare earth metal ion, and a reaction generating layer which is formed by an in-situ reduction reaction when a thermally reducible metal, which can reduce a metal ion in the inorganic compound to a metal in a vacuum is deposited on the inorganic compound constituting the layer. ### Claim 22 (depends on 20, 21) The organic electroluminescent device according to claim 20 or 21, wherein the thermally reducible metal includes at least one selected from Aluminum, Zirconium, Silicon, Titanium and Tungsten. ### Claim 23 (depends on 1) The organic electroluminescent device according to claim 1, wherein said light-emissive unit comprises a structure, as a layer located on an anode side of said charge generation layer and being adjacent thereto, in which a layer of a mixture including an organic compound and an electron donating dopant is formed, thereafter, a reaction generating layer is generated by an in-situ reduction reaction when a thermally reducible metal, which can reduce an alkaline metal ion, an alkaline earth metal ion or a rare earth metal ion to a metal in a vacuum, is deposited on an organic metal complex compound containing at least one metal ion selected from an alkaline metal ion; an alkaline earth metal ion and a rare earth metal ion. ### Claim 24 (depends on 1) The organic electroluminescent device according to claim 1, wherein said light-emissive unit comprises a structure, as a layer located on an anode side of said charge generation layer and being adjacent thereto, in which a layer of a mixture including an organic compound and an electron donating dopant is formed, thereafter, a reaction generating layer is generated by an in-situ reduction reaction when a thermally reducible metal, which can reduce an alkaline metal ion, an alkaline earth metal ion or a rare earth metal ion to a metal in a vacuum, is deposited on an inorganic compound containing at least one metal ion selected from an alkaline metal ion, an alkaline earth metal ion and a rare earth metal ion. ### Claim 25 (depends on 1, 2) The organic electroluminescent device according to claim 1 or 2, in which said light-emissive unit comprises, as a layer located on a cathode side of said charge generation layer and being adjacent thereto, a hole injection layer comprising a mixture of an organic compound and an electron accepting compound having a property capable of oxidizing said organic compound in terms of Lewis acid chemistry. ### Claim 26 (depends on 25) The organic electroluminescent device according to claim 25, wherein the electron accepting compound having a property capable of oxidizing the organic compound in said hole injection layer in terms of Lewis acid chemistry is provided in a molar ratio of 0.01 to 10 with respect to the organic compound. ### Claim 27 (depends on 1, 2) The organic electroluminescent device according to claim 1 or 2, wherein said light-emissive unit comprises, as a layer located on a cathode side of said charge generation layer and being adjacent thereto, a hole injection layer including an electron accepting compound and having a thickness of not more than 30 nm. ### Claim 28 (depends on 1, 2) The organic electroluminescent device according to claim 1 or 2, wherein said light-emissive units each have different emission spectrums. ### Claim 29 (depends on 1, 2) The organic electroluminescent device according to claim 1 or 2, wherein said organic electroluminescent device emits white light due to superimposing of different lights from each light-emissive unit. ### Claim 30 (depends on 1, 2) The organic electroluminescent device according to claim 1 or 2, wherein at least one of said light-emissive units includes a light-emissive layer containing a phosphorescent material. ### Claim 31 (depends on 1, 2) The organic electroluminescent device according to claim 1 or 2, wherein, in each of said light-emissive units, an optical path length from a light-emissive site to a light-reflective metal electrode is an odd-numbered times a quarter wavelength of light. ### Claim 32 (depends on 1, 2) The organic electroluminescent device according to claim 1 or 2, wherein all the layers including said light-emissive units, said charge generation layer, and an electrode layer are formed on a substrate by heating a vaporizable material in a vacuum to deposit one of a vaporized and sublimed material on the substrate; wherein upon depositing said one of vaporized and sublimed material on the substrate, a substrate is transported in a direction of a planar surface thereof, a deposition area being open in a lower surface of the substrate; a container is provided, in a lower position of the transporting substrate, including a vaporizable material having a deposition width which can cover the deposition area extending in a direction perpendicular to the transportation direction of the substrate; and said container is heated to thereby one of vaporize and sublime so as to deposit the vaporizable material provided in the container. ### Claim 33 (depends on 1, 2) The organic electroluminescent device according to claim 1 or 2, wherein a combined thickness of said light-emissive units and said charge generation layers, sandwiched between the cathode and the anode, is greater than 1,000 nm (1 μm). ### Claim 34 (depends on 1, 2) The organic electroluminescent device according to claim 1 or 2, wherein said organic electroluminescent device is operated at a driving voltage of more than 25 volts. ### Claim 35 (depends on 1, 2) The organic electroluminescent device according to claim 1 or 2, wherein light can be passed in only one direction which is one of an anode electrode direction and a cathode electrode direction, from a light generation site in the organic electroluminescent device, wherein light advancing in a direction opposite to said only one direction is absorbed by a light-absorbing medium, and wherein, in each of said light-emissive units, a light interference effect is removed so that an adjustment of an optical path length from a light-emissive site of said light-emissive layers to a light-reflective metal electrode is substantially not necessary. ### Claim 36 (depends on 1, 2) The organic electroluminescent device according to claim 1 or 2, wherein a light advancing in one direction which is one of an anode electrode direction and a cathode electrode direction, from a light generation site in the organic electroluminescent device is reflected diffusely by a diffused reflection medium, and wherein, in each of said light-emissive units, a light interference effect is removed, so that an adjustment of an optical path length from a light-emissive site of said light-emissive layers to a light-reflective metal electrode is substantially not necessary.