DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
This Office action is in response to the amendment filed January 14, 2026, which amends claims 2, 3, 5, 7-10, and 15 and adds claims 18-20. Claims 1-20 are pending.
Response to Amendment
Applicant’s amendment of the claims, filed January 14, 2026, caused the withdrawal of the rejection of claims 2, 3, 5, 7-10, and 15 under 35 U.S.C. 112(b) as set forth in the Office action mailed October 22, 2025.
Response to Arguments
Applicant's arguments filed January 14, 2026 have been fully considered but they are not persuasive.
Regarding the applicant’s argument that the device of the instant application shows superior results because the device of the instant applicant comprises two host materials and Lee only comprises a single host, the Office points out that Yu shows that when two host materials are used instead of one host material the device has improved properties. The prior art teaches the applicant’s expected results and the applicant’s arguments are not persuasive.
In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
Neither Lee or Yu need to teach all of the applicant’s claimed limitations. Yu teaches the improvements of adding a second host material to a light emitting layer. The teachings of Yu would direct one of ordinary skill in the art to add a second host material and the applicant’s argument is not persuasive.
Regarding the applicant’s argument that the applicant’s claimed composition should be considered as a whole and not a first compound and a second compound, the Office points out that the applicant only shows composition comprising two host materials that meet the applicant’s claimed compounds. The applicant does not provide any results with two host materials where either both or one of the hosts does not meet the applicant’s claimed compounds. It is unclear from the applicant’s results if the applicant’s mixed host materials is superior compared to other mixed host materials. The applicant’s arguments are not persuasive.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claim(s) 1-13 and 16-20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Lee et al. (KR2015-0077220) (hereafter “Lee”), where a machine translation is used as the English equivalent, in view of Yu et al. (US 2012/0273764) (hereafter “Yu”).
Regarding claims 1-13 and 16-20, Lee teaches an electroluminescent device comprising an anode, a hole transporting layer, a light emitting layer, an electron transporting layer, and a cathode (pages 38-40 of the machine translation). Lee teaches that the light emitting layer comprises a host material and a phosphorescent dopant (pages 38-40). Lee teaches that the host material can have the following structure,
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are a few examples (pages 15-20 of the machine translation). Lee teaches that the electroluminescent device can be used in an electronic apparatus (end of page 3 of the machine translation).
Lee does not teach where the light emitting layer comprises a second host material.
Yu teaches an electroluminescent device comprising a light emitting layer comprising two host materials and a phosphorescent dopant (paragraphs [0132]-[0145]). Yu teaches that the first host material is electron transporting and the second host can be
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, which is host transporting (paragraphs [0132]-[0156]). Yu teaches that adding the second host materials improves the efficiency of the device (paragraphs [0148]-[0161]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device of Lee so the light emitting layer comprises a second host material, such as
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, as taught by Yu. The motivation would have been to improve the efficiency of the device.
Claim(s) 14 and 15 is/are rejected under 35 U.S.C. 103 as being unpatentable over Lee et al. (KR2015-0077220) (hereafter “Lee”), where a machine translation is used as the English equivalent, in view of Yu et al. (US 2012/0273764) (hereafter “Yu” as applied to claims 1-13 and 16-20 above, and further in view of Kwong et al. (US 2008/0261076) (hereafter “Kwong”).
Regarding claims 14 and 15, Lee teaches that the host material can be a host for a blue, red, or green phosphorescent dopant (end of page 3 of the machine translation).
Lee does not teach a phosphorescent dopant that meets applicant’s claimed formula.
Kwong teaches an electroluminescent device using a red phosphorescent dopant (paragraphs [0177]-[0180]). Kwong teaches that the dopant can have the following structure,
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(paragraphs [0177]-[0180]). Kwong teaches that using these dopants leads to devices that emit red light with high efficiency and lifetime (paragraphs [0177]-[0180]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the device of Lee to the phosphorescent dopant is
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as taught by Kwong. The motivation would have been to make a red emitting device with good efficiency and lifetime.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ANDREW K BOHATY whose telephone number is (571)270-1148. The examiner can normally be reached Monday-Friday 7am-4pm.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Curtis Mayes can be reached at (571)272-1234. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/ANDREW K BOHATY/Primary Examiner, Art Unit 1759