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 15, 2026, which amends claims 1, 8, and 14. Claims 1-25 are pending.
Response to Arguments
Applicant's arguments filed January 15, 2026 have been fully considered but they 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).
The Office points out that each reference does need to teach each and every limitation in the claims, but the combination of references need to teach all the applicant’s claimed limitations.
Regarding the combining of Cho with Choi to add a second host material. The Office points out that Cho does not teach the presence of a second host material, but Min teaches that adding a second host material improves the efficiency and lowers the drive voltage of the device. Given that the first host of Choi comprises a triazine group and the second host of Choi does not comprise a triazine group, one of ordinary skill in the art would select the non-triazine containing compounds to select as the second host material to use with the host material of Cho. One would expect that adding the non-triazine host material to the device of Cho one would expect an increase in efficiency and lower drive voltage of the device. The applicant has not provided any information indicating that this is the case. The applicant’s argument is not persuasive.
In response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971).
In response to applicant's argument that the OLED would have had luminous efficiency and luminous life span as well as low driving voltage as shown in the examples, the fact that the inventor has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious. See Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985).
The applicant does not provide any data of the increase in device properties when the number of hosts goes from one to two host materials. The applicant shows results with one host vs two hosts, but does not show results when a single host device is modified to added a second host. The applicant’s argument is not persuasive.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1-25 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Regarding claims 1 and 14, defining C3-C30 hetero aromatic ring group to include an indene ring is indefinite as an indene ring does not comprise a heteroatom and cannot be a hetero aromatic ring group. This is found in the linking of the R moieties among R61 to R68.
Claims 2-13 and 15-25 are rejected due to the dependence of the claims on claims 1 and 14.
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) 1-8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Cho et al. (US 2014/0374711) (hereafter “Cho”) in view of Kwon et al. (US 2022/0069237) (hereafter “Kwon”) and Choi et al. (WO 2018/026197) (hereafter “Choi”), where a machine translation is used as the English equivalent.
Regarding claims 1-8, Cho teaches an electroluminescent device comprising an anode a hole transporting layer, a light emitting layer, an electron transporting layer, and a cathode (paragraphs [0323]-[0338]). Cho teaches that the light emitting layer comprises a host material and a phosphorescent dopant (paragraphs [0324] and [0329]). Cho teaches that the phosphorescent dopant can emit green light and can be metal complex (is not limited), but specifically teaches using
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(paragraphs [0323]-[0338]). Cho teaches that the host material can be
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or
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are a few examples (paragraphs [0123] and [0323]-[0338]).
Cho does not teach where the phosphorescent dopant meets applicant’s claimed formula 1 and does not specifically teach where the layer comprises a second host material.
Kwon teaches green emitting phosphorescent dopants for use in electroluminescent devices (paragraphs [0149] and [0290]-[0295]). Kwon teaches that the phosphorescent dopant can be
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or
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are a few examples (paragraphs [0145], [0149], and [0290]-[0295]). Kwon teaches that when these metal complexes are used instead of
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, the device has improved EQE and lifetime (paragraphs [0149] and [0290]-[0297]).
Choi teaches an comprising two host materials and a green phosphorescent dopant (page 96 of the machine translation). Choi teaches that the first host material can comprise a triazine group and the second host material can be a compound, such as
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,
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, or
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are a few examples (pages 22-25 and 96-99 of the machine translation and paragraphs [237]-[274] and [737] of the WO document). Choi teaches that when these compounds are sued as the second host material the device has a lower drive voltage and improved efficiency (pages 96-99 of the machine translation and paragraph [737] of the WO document).
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 Cho so the phosphorescent dopant was
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or
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as taught by Kwon. The motivation would have been to improve the EQE and lifetime of the device.
Furthermore, 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 Cho to include a second host material,
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, or
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as taught by Choi. The motivation would have been to improve the lifetime and efficiency of the device.
Claim(s) 9-25 is/are rejected under 35 U.S.C. 103 as being unpatentable over Cho et al. (US 2014/0374711) (hereafter “Cho”) in view of Kwon et al. (US 2022/0069237) (hereafter “Kwon”) and Choi et al. (WO 2018/026197) (hereafter “Choi”), where a machine translation is used as the English equivalent, as applied to claims 1-8 above, and further in view of Kim et al. (US 2015/0280159) (hereafter “Kim”).
Regarding claims 9-25, Cho in view of Kwon and Choi does not teach where the electroluminescent device is a tandem electroluminescent device with a charge generation layer.
Kim teaches a tandem electroluminescent device comprising an anode, first emitting unit, a charge generation layer, a second emitting unit, an optional charge generation layer, an optional third emitting unit, and a cathode (paragraphs [0021]-[0068]). Kim teaches that each emitting unit can have a hole transporting layer, a light emitting layer, and an electron transporting layer, where the light emitting layer can comprise 1, 2 or 3 layers (paragraphs [0021]-[0068]). Kim teaches that the light emitting layer in the first emitting unit can emit blue light, the light emitting layer in the second emitting unit comprises multiple layer, 2 or 3 layers, where one layer emits red light, the second layer can emit green light, and the third can emit green/yellow, and the light emitting layer of the third emitting unit can emit blue light (paragraphs [0090]-[0106]). Kim teaches that using tandem electroluminescent devices leads to improved color reproduction range and emitting efficiency (paragraph [0008]).
It would have been obvious to one of ordinary skill the art at the time before the effective filing date of the claimed invention so electroluminescent device of Cho in view of Kwon and Choi is made into a tandem electroluminescent device as taught by Kim. The motivation would have been to improve the reproduction range and emitting efficiency of the device.
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