Ex Parte Tung et alDownload PDFPatent Trial and Appeal BoardDec 31, 201411105666 (P.T.A.B. Dec. 31, 2014) Copy Citation UNITED STATES PATENT AND TRADEMARK OFFICE UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O. Box 1450 Alexandria, Virginia 22313-1450 www.uspto.gov APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO. 11/105,666 04/13/2005 Yeh-Jiun Tung F7059-16601 2040 111687 7590 12/31/2014 Duane Morris LLP (UDC) 30 South 17th Street Philadelphia, PA 19103 EXAMINER CROUSE, BRETT ALAN ART UNIT PAPER NUMBER 1786 MAIL DATE DELIVERY MODE 12/31/2014 PAPER Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE ____________________ BEFORE THE PATENT TRIAL AND APPEAL BOARD ____________________ Ex parte YEH-JIUN TUNG, MICHAEL S. WEAVER, MICHAEL HACK, and JAMES ESLER ____________________ Appeal 2013-001527 Application 11/105,666 Technology Center 1700 ____________________ Before JEFFREY T. SMITH, KAREN M. HASTINGS, and MICHAEL P. COLAIANNI, Administrative Patent Judges. SMITH, Administrative Patent Judge. DECISION ON APPEAL STATEMENT OF CASE Appellants appeal under 35 U.S.C. § 134 from the Examiner’s decision to reject claims 1 through 5, 7 through 18, 20 through 28, 31 through 33, and 36. We have jurisdiction under 35 U.S.C. § 6(b). Appeal 2013-001527 Application 11/105,666 2 The claims are directed to an organic light emitting device that emits white light using a combination of blue fluorescent emitters and phosphorescent emitters in separate emissive layers. App. Br. 3. Claim 1 illustrates the subject matter on appeal and is reproduced below: 1. An organic light emitting device comprising: a cathode; a first emissive layer comprising a fluorescent blue emitting material as a dopant in a host material; a spacer layer; a second emissive layer comprising a phosphorescent emitting material as a dopant in a host material; and an anode; wherein, the spacer layer is between the first emissive layer and the second emissive layer, the spacer layer inhibits quenching of the triplet excitons in the second emissive layer; an interface between the spacer layer and the first emissive layer forms a heterojunction; and the spacer layer comprises a material that has a triplet energy that is higher than the triplet energy of the phosphorescent emitting material; and wherein a combined emission of the emitting materials gives a white emission from the device. The Examiner relied on the following references in rejecting the appealed subject matter: Kim US 2002/0027416 Al Mar. 7, 2002 Towns US 6,423,428 B1 July 23, 2002 Lin US 2004/0104394 Al Jun. 3, 2004 Appeal 2013-001527 Application 11/105,666 3 Kwong US 2006/0222886 A1 Oct. 5, 2006 Toyama JP 2001-118682 Apr. 27, 2001 Kohama JP 2002-063988 Feb. 28, 2002 Travis Thoms et al., “Improved host material design for phosphorescent guest-host systems” 436 THIN SOLID FILMS, 264–268 (2003), . A. K. Bansal et al., PHOTODYNAMICS OF OLED TRIPLET EMITTERS Ir(ppy) 3 AND PtOEP, 52 UKRAINIAN JOURNAL OF PHYSICS 4, 353–358 (2007). Masahiro Hiramoto et al., Photocurrent multiplication phenomenon at organic/organic heterojunction and application to optical computing device combining with organic electroluminescence, 91 SYNTHETIC METALS, 77–79 (1997) Appellants (App. Br. 2, 4) request review of the following rejection from the Examiner’s Final Office Action: I. Claims 1, 5, 7–10, 13–15, 19–24, 27, 28, 31–33, and 36 rejected under 35 U.S.C. § 103(a) as unpatentable over Lin, Kim, Thoms, Bansal, and Hiramoto. II. Claims 2, 3, 11, 12, 16, 17, 25, and 26 rejected under 35 U.S.C. § 103(a) as unpatentable over Lin, Kim, Thoms, Bansal, and Kwong. III. Claims 2, 3, 11, 12, 16, 17, 25, and 26 rejected under 35 U.S.C. § 103(a) as unpatentable over Lin, Kim, Thoms, Bansal, and Toyama. IV. Claims 2, 3, 11, 12, 16, 17, 25, and 26 rejected under 35 U.S.C. § 103(a) as unpatentable over Lin, Kim, Thoms, Bansal, and Kohama. V. Claims 4 and 18 rejected under 35 U.S.C. § 103(a) as unpatentable over Lin, Kim, Thoms, Bansal, and Towns. Appeal 2013-001527 Application 11/105,666 4 OPINION Prior Art Rejections under 35 U.S.C. § 103(a) The dispositive issue on appeal is: Did the Examiner err in determining that the combined teachings of Lin and Kim would have led one skilled in the art to an organic light emitting device having an emissive layer comprising a fluorescent blue emitting material as a dopant in a host material and an emissive layer comprising a phosphorescent emitting material as a dopant in a host material separated by a spacer layer as required by the subject matter of independent claims 1 and 13? 1, 2 After review of the respective positions provided by Appellants and the Examiner, we REVERSE for the reasons presented by Appellants. The Examiner found Lin discloses an organic light emitting device that emits white light using a combination of blue fluorescent emitters and phosphorescent emitters in separate emissive layers. Ans. 5; Lin Figure 4, ¶¶ 19, 27. The Examiner found Lin does not disclose a spacer layer as required by the subject matter of independent claim 1. Ans. 5. The Examiner found Kim teaches an electroluminescent device structure that emits white light where the electroluminescent device comprises two light emitting layers and a buffer layer there between as a spacer. Ans. 6; Kim Figures 2, 3, ¶¶ 37–41, 60. The Examiner found Kim discloses the hole transport and electron transport layers comprises a light emitting dopant to adjust the luminous color and improve thermal stability to extend device life, 1 We limit our discussion to independent claim 1. 2 A discussion of Thoms, Bansal and Hiramoto is unnecessary for disposition of this appeal. These references were cited to address features not related to the dispositive issue on appeal. Appeal 2013-001527 Application 11/105,666 5 including blue fluorescent emissive materials. Ans. 6; Kim ¶¶ 49–52. The Examiner found it would have been obvious to one of ordinary skill in the art to incorporate a spacer layer into the device of Lin to provide color tuning while improving the thermal stability of the device as taught by Kim. Ans. 7; Kim ¶¶ 31, 36. Appellants argue Lin is directed to an organic light emitting device comprising an emissive layer having phosphorescent emitting material and an emissive layer comprising fluorescent material that are not separated by a spacer. App. Br. 7–8; Lin ¶ 19. Appellants also argue that Kim discloses a spacer layer between emissive layers comprising fluorescent emitting materials only, which emit light from singlet excitons. App. Br. 8; Kim ¶ 9. According to Appellants, Kim does not disclose or suggest an emissive layer comprising a phosphorescent emitting material as a dopant in a host material and, thus, is not concerned with the quenching of triplet excitons from the phosphorescent emitting material. App. Br. 8. Thus, Appellants argue there is no motivation, absent hindsight, to combine the disclosures of Lin and Kim. Id. at 8–9. We agree with Appellants. While the Examiner asserts that the use of Kim’s spacer layer would in Lin’s electroluminescence device would lead to the claimed invention (Ans. 12–14), the Examiner has not adequately explained why a spacer used in Kim’s electrolunminiscence device having emissive layers comprising only fluorescent materials would have been suitable for incorporation into the electroluminescence device of Lin, which includes an emissive layer comprising phosphorescent materials. The Examiner has not adequately explained how one skilled in the art would Appeal 2013-001527 Application 11/105,666 6 have incorporated Kim’s spacer into Lin’s electroluminescence device to arrive to the subject matter of independent claim 1. Under these circumstances, we cannot conclude that the Examiner has met the minimum threshold of establishing a prima facie case of obviousness under 35 U.S.C. § 103(a). See In re Oetiker, 977 F.2d 1443, 1445 (Fed. Cir. 1992); KSR Int’l Co. v. Teleflex, Inc., 550 U.S. 398, 418 (2007) (quoting In re Kahn, 441 F.3d 977, 988 (Fed. Cir. 2006)). Accordingly, we reverse the Examiner’s prior art rejection of claims 1, 5, 7–10, 13–15, 19–24, 27, 28, 31–33, and 36 under 35 U.S.C. § 103(a) as unpatentable over Lin, Kim, Thoms, Bansal and Hiramoto for the reasons presented by Appellants and given above. The Examiner separately rejected claims 2–4, 11, 12, 16–18, 25, and 26 under 35 U.S.C. § 103(a) as unpatentable over Lin, Kim, Thoms and Bansal in view of a number of secondary references (Rejections II–V). Ans. 8–12. However, these additional references are not relied upon by the Examiner to overcome the above noted deficiencies of Lin and Kim. Accordingly, we also reverse the Examiner’s § 103 rejections (Rejections II– V) for the reasons given above. ORDER The Examiner’s prior art rejections of claims 1–5, 7–18, 20–28, 31–33 and, 36 under 35 U.S.C. § 103(a) are reversed. REVERSED lp Copy with citationCopy as parenthetical citation