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 .
The amendment of 04/29/2026 has been entered.
Disposition of claims:
Claims 1 and 5–8 have been amended.
Claims 4 and 8 have been withdrawn due to the species election of 10/23/2025.
Claim 16 has been newly added.
Claims 1–3, 5–7, 9–16 are pending.
Applicant’s arguments (see page 25 of the reply filed 04/29/2026) regarding the rejections of Claims 1, 2, 5, and 9–15 under 35 U.S.C. §102(a)(1) and (a)(2) as being anticipated by Park et al. (WO 2021/101117, hereafter “Park”) set forth in the Office Action of 02/24/2026 have been fully considered and have been withdrawn since independent claim 1 has been amended to define “substituted” in Chemical Formula IV to preclude C13+ heteroaryl groups, rendering the rejections moot.
Applicant’s arguments (see page 28 of the reply filed 04/29/2026) regarding the rejections of Claims 1–3, 5–7, and 9–15 under 35 U.S.C. §103 as being unpatentable over Ahn et al. (WO 2012/039561, hereafter “Ahn”) in view of Tanaka et al. (US 2016/028516, hereafter “Tanaka”) set forth in the Office Action of 02/24/2026 have been fully considered and have been withdrawn since independent claim 1 has been amended to define “substituted” in Chemical Formula IV to preclude C13+ heteroaryl groups, rendering the rejections moot.
Therefore, a new round of rejections has been necessitated by amendment.
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.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1–2, 5–6, 9–16 are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. (US 2015/0318511 A1, hereafter “Kim”) in view of Tanaka et al. (US 2016/0268516 A1, hereafter “Tanaka”).
Kim teaches an organic light emitting device including an anode, a cathode, and at least one organic layer disposed between the anode and cathode. One of the organic layers is an emission layer which comprises two different hosts [008] – [0009]. Kim further teaches some exemplified hosts such as Compound 1, Compound 2, and Compound 3 (shown below) [0146]. Kim also teaches organic light emitting device examples comprising a plurality of hosts have an increased efficiency and lifetime in comparison to device examples which only contain a single host [Table 1 and Table 2].
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However, Kim does not teach a device with three different host materials or a device comprising Compound 1, Compound 2, and Compound 3 in the emissive layer.
Tanaka teaches host compounds may be used singly or may be used in combination of two or more compounds. By using plural host compounds, it is possible to adjust transfer of charge, thereby it is possible to achieve high efficiency of an organic electroluminescent element [0190].
Therefore, it would have been obvious to one of ordinary skill in the pertinent art before the effective filing date of the claimed invention to use three hosts in the organic light emitting device taught by Kim, based on the teaching of Tanaka. The motivation for doing so would have been to optimize the transfer of charge to thereby achieve high efficiency in an organic light emitting device, as taught by Tanaka.
Additionally, it would have been obvious to one of ordinary skill in the pertinent art before the effective filing date of the claimed invention to choose Compound 1, Compound 2, and Compound 3 as the three host materials, because it would have been choosing from the exemplified host materials taught by Kim, which would have been a choice from a finite number of identified, predictable solutions of a compound useful as the host material in the emissive layer of the organic light emitting device of Kim and possessing the benefits taught by Kim. One of ordinary skill in the art would have been motivated to produce additional devices comprising Compound 1, Compound 2, and Compound 3 having the benefits taught by Kim in order to pursue the known options within his or her technical grasp with a reasonable expectation of success. See MPEP 2143.I.(E).
Per Claims 1, 9, 10, and 11, the organic light emitting device, as described above, comprising Compound 1, Compound 2, and Compound 3 as host materials in the emissive layer reads on Applicant’s limitation since Compound 1 is represented by Chemical Formula I (shown below),
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wherein:
Z1 to Z3 are each N,
L1- and L2 are each a single bond, while L3 is an unsubstituted C6 arylene group (phenylene),
R1 and R2 are each an unsubstituted C6 aryl group (phenyl),
R3 to R5 are each hydrogen,
n1 is 3, while n2 and n3 are 4,
Compound 2 reads on Applicant’s Chemical Formula III (shown below),
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258
214
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234
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wherein:
L7 is a single bond
Ar1 is an unsubstituted C6 aryl group (phenyl),
R25 is hydrogen,
n21 is 4,
ring B is represented by Chemical Formula III-3,
L9 is a single bond,
Ar3 is an unsubstituted C6 aryl group (phenyl),
R30 is hydrogen,
n26 is 4,
Compound 3 reads on Applicant’s Chemical Formula IV (shown below),
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400
502
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244
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wherein:
L11 is an unsubstituted C6 arylene group (phenylene),
R31 to R37 are each hydrogen,
n27, n28, n31, n32, n33 are each 4,
n29, n30 are each 3.
Per Claim 2, Compound 1 reads on Applicant’s Chemical Formula I-A (shown below), wherein L1–L3, Z1–Z3, R1–R5, and n1–n3 are each the same as defined above.
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Per Claim 5, Compound 3 reads on Applicant’s Chemical Formula IV-2 (shown below), wherein L11, R31–R37, n27–n33 are each the same as defined above.
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Per Claim 15, Kim teaches the organic light emitting device according to an embodiment may be included in various types of flat panel displays [0211].
Per Claim 16, Compound 3 reads on Applicant’s limitation since L11 is a phenylene group, and R31 to R37 are each hydrogen.
Regarding Claim 12, Kim teaches the weight ratio of the two hosts used in the exemplified devices are 1:1 [0215].
However, Kim does not specifically teach what proportion each of the multiple host compounds may be present at.
Tanaka teaches host compounds may be used in combination of two or more compounds. By using plural host compounds, it is possible to adjust transfer of charge, thereby it is possible to achieve high efficiency of an organic EL element [0190].
Therefore, it is the Examiner’s position that a person of ordinary skill in the art would have mixed the compounds and adjusted the proportions of each compound, to an amount within the range claimed, motivated by the desire to optimize the transfer of charge to achieve a high efficiency organic electroluminescent device. See MPEP 2144.05.
Regarding Claim 13 and 14, Kim teaches the organic light emitting device may be a full color organic light emitting device comprising a red emissive layer, a green emissive layer, and a blue emissive layer [0145]. Also, the exemplified devices taught by Kim also comprise Ir(ppy)3 as the emissive dopant [0215]. Ir(ppy)3 is a well-known green dopant for organic light emitting devices, as evidenced by Baldo et al. (Very high-efficiency green organic light-emitting devices based on electrophosphorescence, Appl. Phys. Lett. 75, 4–6, 1999).
However, Kim does not teach an organic light emitting device wherein the emissive layer comprises Ir(ppy)3, Compound 1, Compound 2, and Compound 3.
It would have been obvious to one of ordinary skill in the pertinent art before the effective filing date of the claimed invention to use Ir(ppy)3 as a dopant in the emissive layer comprising Compound 1, Compound 2, and Compound 3 as described above, because it would have been choosing between the dopants exemplified by Kim, which would have been a choice from a finite number of identified, predictable solutions of a compound useful as the dopant in the emission layer of the organic light emitting device of Kim and possessing the benefits taught by Kim. One of ordinary skill in the art would have been motivated to produce additional devices comprising Ir(ppy)-3 having the benefits taught by Kim in order to pursue the known options within his or her technical grasp with a reasonable expectation of success. See MPEP 2143.I.(E).
The resulting organic light emitting device reads on Applicant’s limitation since it comprises Ir(ppy)3, Compound 1, Compound 2, and Compound 3 in the emissive layer.
Regarding Claim 6, Compound 3 does not read on Applicant’s Chemical Formula IV-4 because it is connected to the 3-position instead of the 1-position (shown below). Kim also teaches organic light emitting device examples comprising a plurality of hosts taught by Kim have an increased efficiency and lifetime in comparison to device examples which only contain a single host [Table 1 and Table 2].
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Given the teachings of Kim, it would have been obvious to one of ordinary skill in the pertinent art before the effective filing date of the claimed invention to make the positional isomer of Compound 3 wherein the phenylene is connected to the 1-position instead of the 3-position. One of ordinary skill in the pertinent art would have been motivated to produce the positional isomers of the compound represented by Compound 3 in order to pursue the known options within his or her technical grasp and would expect the isomeric compounds to be useful as a host material in the emissive layer of the organic light emitting device of Kim and possess the properties taught by Kim. A prima facie case of obviousness exists when chemical compounds have very close structural similarity and similar utilities. See MPEP 2144.09 I. When compounds which are position isomers or homologs are of sufficiently close structural similarity, there is an expectation that such compounds possess similar properties. See MPEP 2144.09 II.
The modified version of Compound 3 (hereafter “Modified Compound 3”) reads on Applicant’s Chemical Formula IV-4 (shown below), wherein L11 is an unsubstituted phenylene group, and R31 to R37 are each hydrogen.
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Claims 3 and 7 are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. (US 2015/0318511 A1) in view of Tanaka et al. (US 2016/0268516 A1) as applied to claim 1–2, 5–6, 9–16 above, and further in view of Yu et al. (US 2012/0273764 A1, hereafter “Yu”).
Regarding Claims 3, Compound 2 does not read on Applicant’s Chemical Formula III-F.
Yu Teaches a composition including a first host compound which may be represented by Chemical Formula 32 and Chemical Formula 20 [0025]. Chemical Formula 32 is identical to Compound 2 taught by Kim. The only difference between Chemical Formula 32 and Chemical Formula 20 is the fusion of the two carbazole moieties. Therefore, Yu teaches that Chemical Formula 32 and Chemical Formula 20 are obvious variants of each other and may be suitably replaced as a host material in a composition. Yu teaches that organic photoelectric devices may exhibit excellent efficiency, driving voltage, and lifespan characteristics when using the host material composition of present disclosure [0162].
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Therefore, given the general formula and teachings of Yu, it would have been obvious to one of ordinary skill in the pertinent art before the effective filing date of the claimed invention to substitute Compound 2, identical to Chemical Formula 32, for Chemical Formula 20, because Yu teaches the variable may suitably be selected as a host material. The substitution would have been one preferred element for another and one of ordinary skill in the pertinent art would reasonably expect the predictable result that the modified compound would be useful as a host material in the emission layer of the organic light emitting device of Kim and possess the benefits taught by Yu. See MPEP 2143.I.(B).
Per Claim 3, replacing Compound 2 with Chemical Formula 20 (hereafter “Compound 4”) meets Applicant’s limitation since Compound 4 reads on Applicant’s Chemical Formula III-F (shown below), wherein
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wherein:
L7 is a single bond
Ar1 is an unsubstituted C6 aryl group (phenyl),
R25 is hydrogen,
n21 is 4,
R29 is hydrogen,
n25 is 2
ring B is represented by Chemical Formula III-4,
L9 is a single bond,
Ar3 is an unsubstituted C6 aryl group (phenyl),
R30 is hydrogen,
n26 is 4.
Per Claim 7, an organic light emitting device comprising Compound 1, Compound 4, and Modified Compound 3 as host materials in the emissive layer, as discussed above, reads on Applicant’s limitation since Compound 1 reads on Applicant’s Chemical Formula 1-1 (shown below),
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wherein:
L1- and L2 are each a single bond, while L3 is an unsubstituted C6 arylene group (phenylene),
R1 and R2 are each an unsubstituted C6 aryl group (phenyl),
R3 to R5 are each hydrogen,
n1 is 3, while n2 and n3 are 4,
Compound 4 reads on Applicant’s Chemical Formula III-F (shown below),
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241
227
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wherein:
L7 is a single bond
Ar1 is an unsubstituted C6 aryl group (phenyl),
R25 is hydrogen,
n21 is 4,
R29 is hydrogen,
n25 is 2
L9 is a single bond,
Ar3 is an unsubstituted C6 aryl group (phenyl),
R30 is hydrogen,
n26 is 4,
Modified Compound 3 reads on Applicant’s Chemical Formula IV-4 (shown below),
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241
379
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wherein:
L11 is an unsubstituted C6 arylene group (phenylene),
R31 to R37 are each hydrogen,
n27, n28, n31, n32, n33 are each 4,
n29, n30 are each 3.
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 JAMES RICHARD FORTWENGLER whose telephone number is (571)272-5433. The examiner can normally be reached Monday - Friday, 8 am - 5 pm.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Marla McConnell can be reached at (571) 270-7692. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/J.R.F./ Examiner, Art Unit 1789
/MARLA D MCCONNELL/ Supervisory Patent Examiner, Art Unit 1789
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