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 April 6, 2026, which amends claim 1, cancels claims 5-11, and adds claims 13-15. Clams 1-4 and 12-15 are pending.
Response to Amendment
Applicant’s amendment of the claims, filed April 6, 2026, caused the withdrawal of the rejection of claims 1-12 under 35 U.S.C. 103 as being unpatentable over Li et al. (CN 110957435) in view of Song et al. (US 2013/0069073) and Cha et al. (KR2018-0098121) as set forth in the Office action mailed January 13, 2026.
Response to Arguments
Applicant's arguments filed April 6, 2026 have been fully considered but they are not persuasive.
The applicant’s amendment of the claims overcomes the rejection in the Office action mailed January 13, 2026 because Li in view of Song and Cha do not teach the applicant’s claimed host compound. However, Suh which was cited as pertinent art does teach the applicant’s claimed host materials and Suh teaches advantages for using these host materials (see rejection below).
Regarding the applicant’s argument that the claimed selection of materials leads to better performance compared other devices that do not meet the claimed energy limitations. The Office points out that the applicant argument that the energy level and the chemical structures are important to the observed results, but the applicant does not provide results where the applicant’s energy and property limitations are meet and the chemical structure are not meet. It is unclear from the results what is causing what is observe, the energy properties of the compounds, the compounds used, or both. Furthermore, the applicant’s specification does not provide any properties information for the compounds used in the comparative examples, so it is unclear the difference in the layers besides the chemical structures. The Office also points out that the applicant only provides a limited number of compounds used as the host and as the ETL, but the applicant claims a variety of each. The applicant also argues that the selection of each material is important for each layer and yet it is unclear if the same results would be observed if a different emitting material as the applicant’s claims do not limit the guest material used. The applicant’s argument is 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) 1-4 and 12-15 is/are rejected under 35 U.S.C. 103 as being unpatentable over Li et al. (CN 110957435) (hereafter “Li”), where a machine translation is used as the English equivalent, in view of Song et al. (US 2013/0069073) (hereafter “Song”), and Suh et al. (US 2019/0296243) (hereafter “Suh”).
Regarding claims 1-4 and 12-15, Li teaches an electroluminescent device comprising an anode, a hole injection layer, a hole transporting layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transporting layer, electron injection layer, and a cathode (pages 15 and 16 of the machine translation). Li teaches that the light emitting layer comprises an anthracene host material and a dopant (pages 3-13 of the machine translation). Li teaches that the host material can have the following structure,
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, and
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are few examples and all meet applicant’s formula 1 (pages 3-10 of the machine translation). Li teaches that the T1 energy of the dopant is higher than the host material and the S1 of the host is higher than the dopant (pages 22-24 of the machine translation). Li teaches that the substituents on the anthracene compounds can form a fused ring (pages 3 and 4 of the machine translation). Li teaches that both hole transporting layer and the electron blocking layer are composed of arylamine and/or carbazole containing compounds (page 22 of the machine translation). Li teaches that the electroluminescent device can be used in display device (page 1 of the machine translation).
Li does not teach how the triplet energy of the electron blocking layer and the hole blocking layer relate to the triplet energy of the host material and does not teach where the electron transporting material is a triazine compound.
Song teaches that the T1 of the electron blocking layer and the T1 of the hole blocking layer should be higher than the T1 of the host material (paragraphs [0083]-[0096], Figs. 4 and 5). Song teaches that having this energy relationship prevents the excitons or electrons from leaving the light emitting layer and going into the other layers and effecting the efficiency of the device (paragraphs [0097]-[0102]).
Suh teaches electroluminescent device comprising anthracene host compounds substituted with a dibenzofuran group, such as
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(paragraphs [0077] and [0156]-[0166]) (this compound is claimed by the applicant). Suh teaches that the layer next to and in contact with the light emitting layer can be composed of spirobifluorene compounds substituted with a triazine groups, such as
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(paragraph [0091] and [0156]-[0166]) (claimed by the applicant). Suh teaches that when the host materials are used with conjunction with the spirobifluorene compound, the device has improved lifetime and efficiency (paragraphs [0156]-[0166]). Suh comparative host materials are similar to the host materials of Li.
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 Li so the T1 energy of the hole blocking material and the electron blocking material is higher than the T1 of the host material, as taught by Song, and where the host is composed of
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and the electron transporting layer is composed of
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as taught by Suh. The motivation would have been to keep the excitons and electrons in the light emitting layer and improve the lifetime and efficiency of the device. The combination would lead to a device where the applicant’s claimed energy limitations would naturally flow. The Office points out claimed energy properties of 2-4 and 13-15 are common and well known in the art and the compounds of the combination would meet these limitations.
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
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