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 24, 2026, which amends claims 1 and 20. Claims 1-15 and 17-21 are pending.
Response to Arguments
Applicant's arguments filed April 24, 2026 have been fully considered but they are not persuasive.
In response to applicant's argument that the prior art references do not teach or make obvious the applicant’s claimed light emitting layer containing a fluorescent dopant and a boron material acting as a sensitizer, the test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference; nor is it that the claimed invention must be expressly suggested in any one or all of the references. Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981).
The Office points out that the teachings of the prior art references would lead to the applicant’s claimed invention. The Office points out that Tanimoto teaches that one can achieve high light emission efficiency by incorporating a TADF compound as an assisting dopant in the layer emitting layer (the material is acting as a third component) (paragraph [0010]). Tanimoto also teaches that energy properties needed for the host, emitting dopant, and assisting dopant. Given these teachings of Tanimoto, any TADF material can be used as the assisting dopant as long as the energy requirements are met. One of ordinary skill in the art would expect that any TADF material that meets the energy relationship teachings of Tanimoto could be used as an assisting dopant in the device of Hatakeyama. Although Hatakeyama 2020 does not specifically teach the boron compounds for use as an assisting dopant, the teachings of Tanimoto would direct one to select a TADF material that would meet the energy relationship taught. The teachings of Tanimoto would direct one of ordinary skill in the art to select materials to meet the energy relationships and the select compounds based on the energy properties of the compounds and not the names of the compounds. The applicant’s argument is not persuasive.
The applicant has not provided any evidence that the compounds of the prior art references would not meet the energy relationship teachings of Tanimoto. 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) 1-15 and 17-21 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hatakeyama et al. (US 2015/0236274) (hereafter “Hatakeyama”) in view of Tanimoto et al. (US 2016/0197282) (hereafter “Tanimoto”), Forrest et al. (US 2015/00349286) (hereafter “Forrest”), and Hatakeyama et al. (WO 2020/040298) (hereafter “Hatakeyama 2020”), where a machine translation is used as the English equivalent.
Regarding claims 1-15 and 17-21, Hatakeyama teaches an electroluminescent device comprising an anode, a hole transporting layer, a light emitting layer, an electron transporting layer, and a cathode (paragraphs [0582]-[0585]). Hatakeyama teaches that the light emitting layer comprises a host material and a dopant (paragraph [0583]). Hatakeyama teaches that the dopant can have the following structure,
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(paragraphs [0034] and [0583]).
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is a compound that applicant’s teaches that corresponds to applicant’s claimed second compound and therefore, meets the applicant’s claimed energy limitations. Hatakeyama teaches that the light emitting layer can be used in a consumer product, such as a flat panel display (paragraphs [0265] and [0266]).
Hatakeyama does not where the light emitting layer comprises a second host material and does not teach the energy requirements of the host materials.
Tanimoto teaches that one can achieve high light emission efficiency by incorporating a TADF compound as an assisting dopant in the layer emitting layer (the material is acting as a third component) (paragraph [0010]). Tanimoto teaches that the T1 and S1 values of the host material or materials need to be higher than the T1 and S1 values of both the dopant and the assisting dopant (Fig. 1B). Fig. 1A also shows that the energy difference between the T1 and S1 of the TADF or assisting dopant needs to be smaller than the emitting dopant. Tanimoto teaches that the host material is a carbazole compound and that the light emitting layer can comprise more than one host material (paragraphs [0283]-[0290]).
Forrest teaches that one can increase the lifetime of an electroluminescent device by adding a TADF sensitizer to a light emitting layer composed of a blue fluorescent dopant (paragraph [0048]).
Hatakeyama 2020 teaches TADF compounds that can be used in electroluminescent devices (pages ). Hatakeyama 2020 teaches that the TADF compounds can have the following structure,
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,
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,
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, or
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are a few examples, which are the same as applicant’s claimed first compound (pages 80-95 and 157-162). Hatakeyama 2020 teaches that these compounds have a very small energy difference between the T1 and S1 (page 162 the Table).
It would have been obvious one of ordinary skill in the art at the time the invention was effectively filed to modify to device of Hatakeyama so the device comprises a TADF material, such as the compound taught by Hatakeyama 2020, as a sensitizer, as taught by Forrest, and one or two host materials, as taught by Tanimoto, where the T1 and S1 of each host material is higher than the T1 and S1 of the dopant and TADF material, as taught by Tanimoto. The motivation, as taught by Tanimoto, would have been to improve emission efficiency of the device. The motivation, as taught by Forrest, to add the TADF sensitizer would have been to improve the lifetime of the device.
The combination would lead to a device that comprises a dopant and TADF material that meets the applicant’s claimed second and first compounds and would meet the applicant’s claimed energy 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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