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 .
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.
Claim(s) 9-16 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hatakeyama et al (US 20150236274 A1) in view of Yen (US 20160190470 A1) and further in view of Yamaoka et al (US 20180151630 A1).
Hatakeyama discloses an OLED comprising a compound that displays TADF [0046] having the formulae:
PNG
media_image1.png
372
283
media_image1.png
Greyscale
[p5]
Which reads on the claimed formula 4. The compound can be used with a host material wherein the host is used in an amount of 90 to 99.9 %wt and the inventive compound is used as the dopant in 0.1 to 10 wt% [0118-0119].
Yen discloses an OLED comprising in the light emitting layer a combination of two hosts EX37 and EX50 in a 1:1 ratio in an example [Table 2, p28] having the following formulae:
PNG
media_image2.png
307
588
media_image2.png
Greyscale
[p27] EX50 which reads on the claimed formula 1 and
PNG
media_image3.png
228
402
media_image3.png
Greyscale
[p26] EX33 which reads on the claimed formula 2. The phenylene and aromatic structure of six fused rings reads on the claimed Ar1 and Ar2 wherein that is an unsubstituted linked aromatic group formed by linking 2 to 8 aromatic rings thereof. Yen discloses that the hosts are suitable for TADF light emitting materials [claims 6 and 7]. Yen teaches that the inventive compounds efficiently lower driving voltage, lower power consumption and increase efficiency [abstract].
It would have been obvious to one having ordinary skill in the art at the time of filing of Applicant’s invention to have used the claimed hosts of formula 1 and 2 in the OLED of Hatekayama because Yen teaches that they efficiently lower driving voltage, lower power consumption and increase efficiency.
Modified Hatekayama does not disclose the energy gap between the S1 and T1 states of the emission material.
Yamaoka teaches that TADF is efficiently obtained under the condition where the difference in energy between the triplet excitation energy level and the singlet excitation energy level is preferably larger than 0 eV and smaller than or equal to 0.2 eV, further preferably larger than 0 eV and smaller than or equal to 0.1 eV [0125].
It would have been obvious to one having ordinary skill in the art at the time of filing of Applicant’s invention to have used the claimed energy difference in Modified Hatekayama because Yamaoka teaches that that is the preferred energy gap for thermally delayed fluorescence.
Response to Arguments
Applicant's arguments filed 11/28/2026 have been fully considered but they are not persuasive.
Applicant argues that the host compounds of Yen include a skeleton in which six aromatic rings are fused together and therefore do not correspond to the claimed general formulae (1) and (2) of the claims. This argument is not convincing. The both the phenylene and the six aromatic fused ring structure of Ex50 and Ex33, for instance, together read on the claimed groups for Ar1 and Ar2 that is “an unsubstituted linked aromatic group formed by linking 2 to 8 aromatic rings thereof”. The six aromatic fused ring structure does reads as part of Ar1 and Ar2 rather than a substituent of them.
Applicant argues that Yen and Yamaoka do not provide a specific teaching of a compound of the claimed general formulae (3) or (4). This argument is not convincing. The primary reference Hatakeyama is relied upon to disclose the emitter compound of claimed general formulae (3) or (4).
Applicant argues that Examiner has engaged in improper hindsight to reconstruct the claims by picking and choosing from several references. This argument is not convincing. Applicant’s claims combine:
1) a common boron dopant disclosed by Hatakeyama, and
2) a mixture of a common electron transporting host ETH (triazine containing) and a common hole transporting host HTH (containing carbazoles) disclosed by Yen.
It is known that combining an HTH and an ETH in the light emitting layer of an OLED improves lifespan and efficiency by facilitating the transfer of both holes and electrons. See for example Lee et al (US 20180337361 A1) specifically at [0063], which also discloses the combination of an HTH and an ETH in the light emitting layer. So this is a very straightforward combination of 1) a known dopant with 2) a known mix of two hosts, known to improve efficiency and lifetime. As to the ΔEST of the claims, the ordinarily skilled artisan would understand that for a TADF compound like Hatakeyama it should be within the claimed range having a small ΔEST to facilitate the rISC transfer that enables thermally delayed fluorescence, so it is nearly within the definition of a TADF compound. Nevertheless Yamaoka is cited just to make the ΔEST abundantly and undeniably obvious.
Applicant argues and attempts to show in the Affidavit that they have found unexpected results in using the claimed mixture of host compounds over single host compounds (CE 1-3 and 5-7) as well as over a combination of the claimed Second Host of Formula (2) and an mCBP host in place of the claimed First Host of Formula (1). Applicant uses the same dopant compound in all of the inventive and comparative examples. See Tables 2 and 3 of the Affidavit. This argument is not convincing:
The results are not unexpected. As discussed above, combining an ETH and a HTH in a light emitting layer of an OLED is known to improve efficiency and lifetime. The cited secondary reference Yen teaches the mixture of ETH and HTH efficiently lower driving voltage, lower power consumption and increase efficiency. Lee et al (US 20180337361 A1) teaches that improves lifespan and efficiency [0063]. Regarding the improvement of the Inventive Examples 1-6 and 10 over CE 4 and 8 which use a biscarbazole host mCBP (with the structure below) in place of the bicarbazole hosts of the claimed formula (1), it is also known that using a bicarbazole host can improve the efficiency and lifetime of an OLED device. See for example Xia et al (US 20110260138 A1), which discloses that 3,3’-bicarbazole compounds included in OLED layers as a host [0040], wherein the compounds improve the efficiency and lifetime of the OLED devices [abstract].
Furthermore, this is not a fair comparison to the prior art. As noted, Yen (as well as Lee) explicitly discloses the combination of ETH and HTH. What makes the claims obvious rather than anticipated by Yen, is that the ETH and HTH are combined with a boron dopant. The unexpected results must come from the obvious difference between the closest prior art and the claims, rather than an aspect of the claims that is anticipated by the prior art (and the improvements thereof are expected).
Again, the claims make a very straightforward combination of a known dopant and a known mixture of two hosts materials, and the results appear to be expected and disclosed in the cited references.
Applicant also argues in the Affidavit that the T1 values of the compounds of Yen are lower than the T1 values of the claimed boron dopants, exemplified by compound 4-2, and that the claimed compounds of formula (3) and (4) have higher T1 values than the T1 values of the claimed boron dopants. Applicant argues that this provides improved efficiency. This argument is not convincing. Firstly, as Applicant notes, the effect of having a higher T1 value in the hosts materials to improve efficiency in a TADF light emitting dopant is known from US Patent No. 8,993,129 B2. So finding a host with a higher T1 value would appear to be routine experimentation, rather than an inventive discovery. Furthermore, Applicant has only shown that two compounds of Yen have a lower T1 value than one specific dopant that reads on the claims. Yen discloses many other host compounds, and the claims and primary reference Hatakeyama disclose many other dopants than compound 4-2, so the T1 difference may be in many combinations thereof. Even if the T1 values of the hosts of Yen are always lower than the T1 values of the dopants of Hatakeyama, the combination would still be obvious, since the combination would still be functional, if not including the improve disclosed in US Patent No. 8,993,129 B2.
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 MICHAEL M DOLLINGER whose telephone number is (571)270-5464. The examiner can normally be reached 10am-6:30pm M-F.
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, Randy Gulakowski can be reached at 571-272-1302. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
MICHAEL M. DOLLINGER
Primary Examiner
Art Unit 1766
/MICHAEL M DOLLINGER/ Primary Examiner, Art Unit 1766