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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 06/04/2026 has been entered.
Status of Claims
Claims 8, 17, and 20 are amended due to Applicant's amendment dated 04/29/2026. Claims 1, 3-8, and 10-20 are pending.
Response to Amendment
The rejection of claims 8 and 20 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 as set forth in the previous Office Action is overcome due to the Applicant’s amendment dated 04/29/2026. The rejection is withdrawn.
The rejection of claims 8 and 20 under 35 U.S.C. 112(d) or 35 U.S.C. 112 (pre-AIA ), 4th paragraph, as being of improper dependent form for failing to further limit the subject matter of the claim upon which it depends, or for failing to include all the limitations of the claim upon which it depends as set forth in the previous Office Action is overcome due to the Applicant’s amendment dated 04/29/2026. The rejection is withdrawn.
The rejection of claims 17 and 20 under 35 U.S.C. 103 as being unpatentable over Kim (US 2021/0202876 A1) in view of Meng (English translation of CN 110790782 A obtained from Global Dossier) is overcome due to the Applicant’s amendment dated 04/29/2026. The rejection is withdrawn.
The rejection of claim 19 under 35 U.S.C. 103 as being unpatentable over Kim in view of Meng and Ko (US 2019/0296254 A1) is overcome due to the Applicant’s amendment dated 04/29/2026. The rejection is withdrawn.
Response to Arguments
Applicant’s arguments on pages 37-40 of the reply dated 04/29/2026 with respect to the rejection of claims 17 and 19-20 as set forth in the previous Office Action have been fully considered but they are not persuasive.
Applicant's argument –On pages 37-40, Applicant argues that the cited references do not teach the claims as amended, which require a delayed fluorescent dopant represented by Formula 1 wherein when R2 and/or R13 is the substituted or unsubstituted carbazole group, then R22 is a substituted carbazole group, at least one selected from among R24 and R25 is a group represented by R1-8 and R1-9, and/or R24 and R25 are each a group represented by R1-4.
Examiner's response –As discussed in greater detail in the new grounds of rejection below, the previously cited reference Meng (English translation of CN 110790782 A obtained from Global Dossier) in view of the newly cited reference Kim ‘998 (US 2021/0053998 A1) teach a compound which reads on the amended Formula 1. Accordingly, the cited references teach claims 17 and 19-20 as amended.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 17 and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Kim (US 2021/0202876 A1) in view of Meng (English translation of CN 110790782 A obtained from Global Dossier) and Kim ‘998 (US 2021/0053998 A1).
Regarding claims 17 and 20, Kim teaches an organic light emitting device having increased luminous efficacy of a single color and improved lifespan by including a light emitting layer including a host, a TADF fluorescent dopant and a phosphorescent dopant (abstract; ¶ [0009]-[0010]). In the device, energy is transferred from the phosphorescent dopant to the fluorescent dopant, and thus the phosphorescent dopant is a sensitizer (¶ [0069], [0072], [0100], [0151], and [0178]-[0179]).
Kim teaches an example thereof in Device C which includes an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, and a cathode, wherein the light emitting layer includes a phosphorescent platinum dopant, a boron-based fluorescent (TADF) dopant, a hole transporting host, and an electron transporting host (¶ [0085]-[0088]).
Kim fails to teach a structure for the TADF fluorescent dopant. However, Kim does teach the fluorescent dopant is a boron-based compound (¶ [0077] and [0085]-[0088]).
Meng teaches a dark blue TADF organic light-emitting material represented by the structural units on page 3, wherein the organic light-emitting material provides improved color purity and enhanced stability (beginning of pg. 2 and middle of pg. 3). Meng teaches examples of the organic light-emitting material including compound 79 (pg. 10).
compound 79:
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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 select the TADF fluorescent dopant such that it is a compound represented by Meng’s structural units, based on the teaching of Meng. The motivation for doing so would have been to provide a compound with improved color purity and enhanced stability, as taught by Meng.
In particular, it would have been obvious to one of ordinary skill in the pertinent art before the effective filing date of the claimed invention to select Meng’s compound 79, because it would have been choosing from a list of exemplified compounds represented by Meng’s structural units and taught by Meng, which would have been a choice from a finite number of identified, predictable solutions of a compound useful as the fluorescent dopant in the light emitting layer of the device of Kim and possessing the benefits taught by Meng. One of ordinary skill in the art would have been motivated to produce additional devices comprising compounds represented by Meng’s structural units having the benefits taught by Meng in order to pursue the known options within his or her technical grasp with a reasonable expectation of success. See MPEP 2143.I.(E).
Meng’s compound 79 fails to read on the Formula 1 as it does not comprise a group represented by the claimed R1-8, R1-9, or R1-4 in the location of R24 and R25. However, Meng teaches in the structural units on pg. 3, R2 may be a heterocyclic group, wherein examples thereof include carbazole (bottom of pg. 3 and middle of pg. 4).
structural unit:
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Kim ‘998 teaches a compound represented by Formula 1 for use as a dopant in the light-emitting layer of an organic electroluminescent element, wherein examples of compounds represented by Formula 1 include compound 1-74 (¶ [0012]-[0014]).
1-74:
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Therefore in Meng’s compound 79, given the general formula and teachings of Meng, 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 hydrogen with carbazole in the location of each R2 (as shown by compound 1-74 of Kim ‘998), because Meng teaches R2 may suitably be selected as carbazole. The substitution would have been one known 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 the fluorescent dopant in the light emitting layer of the device of Kim in view of Meng and possess the benefits taught by Kim and Meng. See MPEP 2143.I.(B).
The modified compound 79 reads on the claimed Formula 1 wherein: R1, R3, R4, R11, R12, R14, R21, and R23 are each hydrogen, R2, R13, and R22 are each an unsubstituted carbazole group, and R24 and R25 are each a group represented by R1-4.
The modified compound 79 reads on the claimed compound 17 (claim 20).
Claim 19 is rejected under 35 U.S.C. 103 as being unpatentable over Kim (US 2021/0202876 A1) in view of Meng (English translation of CN 110790782 A obtained from Global Dossier) and Kim ‘998 (US 2021/0053998 A1) as applied to claim 17 above, and further in view of Ko (US 2019/0296254 A1), supporting evidence provided by Seo (US 2016/0064684 A1).
Regarding claim 19, Kim in view of Meng and Kim ‘998 teach the device including a hole transporting host, an electron transporting host, a TADF fluorescent dopant of Meng’s modified compound 79, and phosphorescent dopant, as described above with respect to claim 1.
Kim fails to teach a structure for the hole transporting host, the electron transporting host, and the phosphorescent platinum dopant. However, Kim does not limit the structure of the hosts, and teaches the phosphorescent dopant may be an iridium or platinum complex compound (¶ [0077]).
Ko teaches an organic light-emitting device having high luminescent efficiency and a long lifespan by including a first compound represented by Formula 1, a second compound represented by Formula 2, and a third compound represented by Formula 3 in the emission layer (abstract; ¶ [0005]-[0015]). Ko teaches examples of such devices including Example 1 wherein the first compound is D8, the second compound is a host compound of H2-2, and the third compound is a host compound of H3-2 (Table 3 on pg. 93; structures on pg. 92).
D8:
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H2-2:
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H3-2:
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Seo teaches a material having electron-transport property includes heterocyclic compounds having triazine skeletons and a material having hole-transport property includes compounds having carbazole skeletons (¶ [0163]-[0164]). Accordingly, Ko’s H2-2 is a compound having electron-transport property and Ko’s H3-2 is a compound having hole-transport property.
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 select Ko’s H2-2 as the electron transporting host, Ko’s H3-2 as the hole transporting host, and Ko’s D8 as the phosphorescent dopant (as shown in Ko’s Example 1), to arrive at a device comprising Ko’s first compound, second compound, and third compound, based on the teaching of Ko. The motivation for doing so would have been to provide a device with high luminescent efficiency and a long lifespan, as taught by Ko.
Ko’s H3-2 read on the claimed Formula HT-1 wherein R62 to R69 is a hydrogen atom and R61 is a substituted aryl group having 12 ring-forming carbon atoms, and wherein the substituent is an unsubstituted carbazole group. Accordingly, R61 comprises an unsubstituted carbazole group.
Ko’s H2-2 reads on the claimed Formula ET-1 wherein: X1 to X3 are each N; a1 to a3 are each 0; L1 to L3 are not required to be present; Ar1 and Ar2 are each a substituted arylene group having 6 ring-forming carbon atoms and Ar2 is an unsubstituted arylene group having 6 ring-forming carbon atoms.
Ko’s D8 reads on the claimed Formula M-b wherein: Q1, Q3, and Q4 are each C and Q2 is N; C1 is a substituted heterocycle having 3 ring-forming carbon atoms, C2 is an unsubstituted hydrocarbon ring having 6 ring-forming carbon atoms, C3 is an unsubstituted heterocycle having 12 ring-forming carbon atoms, and C4 is an unsubstituted heterocycle having 5 ring-forming carbon atoms; e1 to e3 are each 1 and e4 is 0; L21 to L23 are each a direct linkage and L24 is not required to be present; d1 is 1 and d2 to d4 are each 0; R31 is an unsubstituted aryl group having 6 ring-forming carbon atoms and R32 to R34 are not required to be present.
Allowable Subject Matter
Claims 1, 3-8, and 10-16 are allowed.
Claim 18 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter:
With respect to claim 1, the prior art does not teach or suggest a light emitting element comprising an emission layer comprising a hole transporting host and a delayed fluorescent dopant; wherein the hole transporting host is represented by Formula HT-1 and the delayed fluorescent dopant is represented by Formula 1; and wherein the hole transporting host has a lower absolute value of a HOMO energy level than the delayed fluorescent dopant, in combination with the remainder of claim 1.
With respect to claim 18, the prior art does not teach or suggest a light emitting element comprising an emission layer comprising a hole transporting host and a delayed fluorescent dopant; wherein the hole transporting host is represented by Formula HT-1 and the delayed fluorescent dopant is represented by Formula 1; and wherein the hole transporting host has a lower absolute value of a HOMO energy level than the delayed fluorescent dopant, in combination with the remainder of claim 18.
Kim (US 2021/0202876 A1), cited in the rejection above, is considered the closest prior art. Kim teaches an organic light emitting device having increased luminous efficacy of a single color and improved lifespan by including a light emitting layer including a host, a TADF fluorescent dopant and a phosphorescent dopant (abstract; ¶ [0009]-[0010]). Kim teaches an example thereof in Device C which includes an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, and a cathode, wherein the light emitting layer includes a phosphorescent platinum dopant, a boron-based fluorescent (TADF) dopant, a hole transporting host, and an electron transporting host (¶ [0085]-[0088]).
Kim is silent as to the hole transporting host having a lower absolute value of a HOMO energy level than the TADF fluorescent dopant. Additionally, Kim fails to teach a hole transporting host represented by Formula HT-1 and a delayed fluorescent dopant represented by Formula 1.
Okamoto (US 2012/0235131 A1), cited in the previous office action dated 09/09/2025, is considered relevant to the claimed invention. Okamoto teaches an organic EL element including an emission layer comprising a host material and an organic light emitting material, wherein the host material is a hole-transporting material, the HOMO energy level of the host is shallower than a HOMO of the organic light emitting material (|HOMO_host| < |HOMO_organic light emitting material|), and the expressions (1) and (2) are satisfied (abstract; ¶ [0016] and [0020]).
0 eV < (|HOMO_organic light emitting material|- |HOMO_host|) ≤ 0.5 eV; and
|LUMO_host| < |LUMO_organic light emitting material|.
By satisfying these conditions, this makes it possible to keep the hole mobility and the electron mobility high in the host material of the emission layer, which provides a device with improved internal quantum yield rate, luminous efficiency, and driving voltage (abstract; ¶ [0017]).
However, Okamoto fails to teach a hole transporting host represented by Formula HT-1 and a delayed fluorescent dopant represented by Formula 1. Additionally, there is nothing in Okamoto that teaches or suggests that a hole transporting host represented by Formula HT-1 and a delayed fluorescent dopant represented by Formula 1 necessarily satisfy the condition wherein the hole transporting host has a lower absolute value of a HOMO energy level than the delayed fluorescent dopant. Accordingly, Okamoto fails to remedy the deficiencies of Kim.
Meng (English translation of CN 110790782 A obtained from Global Dossier), cited in the rejection above, is considered relevant to the claimed invention. Meng teaches a dark blue TADF organic light-emitting material represented by the structural units on page 3, wherein the organic light-emitting material provides improved color purity and enhanced stability (beginning of pg. 2 and middle of pg. 3). Meng teaches examples of the organic light-emitting material including compound 79, which reads on the claimed Formula 1 (pg. 10).
However, Meng fails to teach a hole transporting host represented by Formula HT-1, and is silent as to a hole transporting host having a lower absolute value of a HOMO energy level than the TADF dopant. Additionally, there is nothing in Meng that teaches or suggests that a hole transporting host represented by Formula HT-1 and a delayed fluorescent dopant represented by Formula 1 necessarily satisfy the condition wherein the hole transporting host has a lower absolute value of a HOMO energy level than the delayed fluorescent dopant. Accordingly, Meng fails to remedy the deficiencies of Kim.
Ko (US 2019/0296254 A1), cited in the previous office action dated 09/09/2025, is considered relevant to the claimed invention. Ko teaches an organic light-emitting device in Example 1 comprising a host compound of H3-2 (Table 3 on pg. 93; structures on pg. 92).
H3-2:
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However, Ko fails to teach a delayed fluorescent dopant represented by Formula 1, and is silent as to a hole transporting host having a lower absolute value of a HOMO energy level than a delayed fluorescent dopant. Additionally, there is nothing in Ko that teaches or suggests that a hole transporting host represented by Formula HT-1 and a delayed fluorescent dopant represented by Formula 1 necessarily satisfies the condition wherein the hole transporting host has a lower absolute value of a HOMO energy level than the delayed fluorescent dopant. Accordingly, Ko fails to remedy the deficiencies of Kim.
Thus there is no prior art, either alone or in combination, which teaches or renders obvious a light emitting element comprising an emission layer comprising a hole transporting host and a delayed fluorescent dopant; wherein the hole transporting host is represented by Formula HT-1 and the delayed fluorescent dopant is represented by Formula 1; and wherein the hole transporting host has a lower absolute value of a HOMO energy level than the delayed fluorescent dopant, in combination with the remainder of claim 1.
Likewise, there is no prior art, either alone or in combination, which teaches or renders obvious a light emitting element comprising an emission layer comprising a hole transporting host and a delayed fluorescent dopant; wherein the hole transporting host is represented by Formula HT-1 and the delayed fluorescent dopant is represented by Formula 1; and wherein the hole transporting host has a lower absolute value of a HOMO energy level than the delayed fluorescent dopant, in combination with the remainder of claim 18.
Claims 3-8 and 10-16 depend from claim 1 and thus are allowed for the same reasons presented with respect to claim 1 above.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
US 2021/0066616 A1 teaches the compound below which reads on the claimed Formula 1 wherein: R1 to R23 are each hydrogen and R24 and R25 each comprise an unsubstituted carbazole group (¶ [0072]).
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Contact Information
Any inquiry concerning this communication or earlier communications from the examiner should be directed to BRAELYN R WATSON whose telephone number is (571)272-1822. The examiner can normally be reached M-F 7:30am-5pm.
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/BRAELYN R WATSON/Examiner, Art Unit 1786
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