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 .
Priority
Acknowledgment is made of applicant’s claim for foreign priority under 35 U.S.C. 119 (a)-(d). The certified copy has been filed in parent Application No. EP20162382.4, filed on 03/11/2020.
Information Disclosure Statement
The information disclosure statements (IDSs) submitted on 09/14/2022 and 09/19/2025 were filed after the mailing date of the instant application on 09/08/2022. The submissions are in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statements are being considered by the examiner.
Election/Restrictions
In a requirement for unity of invention dated 10/30/2025, Applicant was required to choose from:
Group I, claims 16-23 and 28-30, drawn to a dual host mixture or an electroluminescent device comprising the dual hosts, or
Group II, claims 24-27, drawn to a process for producing an electroluminescent device comprising dual hosts.
Applicant's election with traverse of Group I, claims 16-23 and 28-30, in the reply filed on 12/29/2025 is acknowledged. The traversal is on the ground(s) that (1) the European Examiner did not require a lack of unity between the original claims, and did not believe that there was a separate invention and (2) that the full scope of the claimed invention does not pose an undue burden on Examiner.
This is not found persuasive because (1) the Examiner is not bound by the decisions or opinions of a separate patent agency and (2) the instant compounds of Group I are classified in H10K 85/00 (Organic materials used in the body or electrodes of devices covered by this class), while the restricted process of Group II is classified in H10K 77/00 (Manufacture or treatment specially adapted for the organic devices covered by this subclass). The separate classifications represent a search burden under MPEP 808.02.
The requirement is still deemed proper and is therefore made FINAL.
Claims 24-27 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected invention, there being no allowable generic or linking claim. Applicant timely traversed the restriction (election) requirement in the reply filed on 12/29/2025.
Group I, claims 16-23 and 28-30, is examined herein.
Response to Amendment
In the response filed 09/08/2022, the claims and specification were amended.
These amendments are hereby entered.
Claims 16-30 have been added.
Claims 1-15 have been canceled.
Claims 16-30 are pending in the application,
of which claims 24-27 are withdrawn from consideration.
Specification
The disclosure is objected to because of the following informalities:
The letters, numbers, and/or bonds in the chemical structures given on pages 150-163 are illegible due to poor resolution. Please correct these structures so all letters, numbers, and/or bonds are clearly visible.
For example, one of the compounds appears to have an incomplete cyclopentyl group. See below.
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Additionally, many of the organometallic structures have missing or illegible elemental symbols, such as the compound below.
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Other compounds have moieties which appear to erroneously fall within the square brackets, such as the compound below.
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Please note that these examples are non-limiting and there may be other structures that require correction. Please check all formulae to make sure they are clear. Applicant may wish to make these structures clearer by increasing the size of the structure and/or font, or by making the bond lines thicker.
Appropriate correction is required.
Claim Objections
Claim 17 is objected to because of the following informalities:
With respect to claim 17, parent claim 16 defines L as being selected from a Markush group containing the option of “single bond”, however, claim 17 only contains reference to “a bond”. The language of dependent claims should mirror parent claims.
Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 21 and 22 are rejected 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.
With respect to claims 21 and 22, the claims recite the limitation “the light-emitting layer”. There is insufficient antecedent bases for this limitation in the claims.
Parent claim 16 requires at least one organic layer comprising at least one light-emitting layer, wherein the at least one light-emitting layer contains at least one compound of host 1 and at least one compound of host 2.
For this reason, it is unclear which light-emitting layer “the light-emitting layer” is referring to.
In continuing examination, “the light-emitting layer” will be interpreted as “the at least one light-emitting layer”.
Also with respect to claim 21, the syntax of the claim is confusing. The claim could be interpreted in a multitude of ways. Three examples are given below.
The first way is that the claim is incomplete because the claim appears to require that the device comprises some unknown element in addition to a light-emitting layer (EML), a hole injection layer (HIL), a hole transport layer (HTL), an electron transport layer (ETL), an electron injection layer (EIL), and/or a hole blocking layer (HBL).
The second way is that the claim requires (1) the device has an EML, a HIL, a HTL, an ETL, an EIL, or (2) that the device comprises an EML and a HBL.
The third way is that the claim requires an EML and at least one of a HIL, a HTL, an ETL, an EIL, and a HBL.
In continuing examination, the claim will be interpreted as, “wherein the device comprises [[, in addition to the]] at least one light-emitting layer (EML), and at least one additional layer selected from the group comprising a hole injection layer (HIL), a hole transport layer (HLT), an electron transport layer (ETL), an electron injection layer (EIL), and[[/or]] a hole blocker layer (HBL).
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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 16-22 and 28-30 are rejected under 35 U.S.C. 103 as being unpatentable over Lee et al. (US 2015/0333273 A1) and further in view of Parham et al. (US 2017/0186965 A1).
With respect to claim 16, Lee discloses an organic electroluminescent device comprising an anode, a cathode (paragraph 0181), and at least one organic layer comprising at least one light-emitting layer (paragraph 0172) and the light emitting layer comprises a condensed cyclic compound represented by Formula 1 (paragraph 0039), such as Compound 1 (page 23), which is pictured below and meets the requirements of the instant host material 2.
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This compound meets the requirements of instant Formula (2) when a and c are 0 and b is 1, q, r, and s are 0 and R1 is not present, A is represented by Formula (3). In Formula (3), one X2 is nitrogen, and the rest are CH and Ar is an aryl group with 6 aromatic ring atoms.
However, while Lee teaches the emission layer may comprise a second host (paragraph 0224), Lee does not teach nor fairly suggest a second host of instant Formula (1).
In analogous art, Parham teaches a compound for use as a matrix material in the emitting layer of an electronic device (paragraph 0106) which has very good properties on use in organic electroluminescent devices, in particular, on the lifetime, efficiency, and voltage (paragraph 0130).
Parham gives an example of the inventive compound in compound p18 (page 189), which is pictured below, and which meets the requirements of instant host material 1.
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This compound meets the requirements of instant Formula (1), when each X is nitrogen, each Y is oxygen, each X1 is CH, L and L1 are single bonds, R0 is a hydrogen atom, n is 3, m is 3, o is 3, and p is 3, Ar2 is an aryl group with 6 ring atoms, and Ar3 is also an aryl group with 6 ring atoms.
It would have been obvious to a person having ordinary skill in the art prior to the effective filing date of the claimed invention to use the matrix material of Parham as the second host in the emitting layer of Lee in order to achieve very good properties on use in organic electroluminescent devices, in particular, on the lifetime, efficiency, and voltage, as taught by Parham.
With respect to claim 17, Lee and Parham teach the device of claim 16, and L in host material 1 is a single bond, as discussed above.
With respect to claim 18, Lee and Parham teach the device of claim16, and host material 2 conforms to instant Formula (2b), as pictured above.
With respect to claim 19, Lee and Parham teach the device of claim 16, and L1 in host material 1 is a single bond, as discussed above.
With respect to claim 20, Lee and Parham teach the device of claim 16, as discussed above.
Parham also teaches that a mixture containing the compound may be used in an electronic device such as an organic electroluminescent device, which includes organic field-quench devices (paragraph 0102).
It would have been obvious to a person having ordinary skill in the art prior to the effective filing date of the claimed invention to use the device of Lee and Parham in a device such as an organic field-quench device, as taught by Parham.
With respect to claim 21, Lee and Parham teach the device of claim 16, and Lee also teaches that the device also comprises at least one of a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, and a hole blocking layer (paragraph 0178) in addition to the aforementioned emission layer.
It would have been obvious to a person having ordinary skill in the art prior to the effective filing date of the claimed invention to include at least one of a HIL, HTL, ETL, EIL, and a HBL in the device, as taught by Lee.
With respect to claim 22, Lee and Parham teach the device of claim 16, and Lee also teaches that the emission layer, in addition to the first and second host material (paragraph 0224), may comprise a phosphorescent dopant (paragraph 0222).
It would have been obvious to a person having ordinary skill in the art prior to the effective filing date of the claimed invention to use a phosphorescent dopant in the light-emitting layer of the device of Lee and Parham, as taught by Lee.
With respect to claim 28, Lee discloses a mixture comprising a condensed cyclic compound as a host material (Compound 3) and a dopant (Ir(ppy)3) (paragraph 0377), wherein the condensed cyclic compound may also be represented by Compound 1 (page 23), which is pictured below and meets the requirements of the instant host material 2.
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This compound meets the requirements of instant Formula (2) when a and c are 0 and b is 1, q, r, and s are 0 and R1 is not present, A is represented by Formula (3). In Formula (3), one X2 is nitrogen, and the rest are CH and Ar is an aryl group with 6 aromatic ring atoms.
However, while Lee teaches the emission layer may comprise a second host (paragraph 0224), Lee does not teach nor fairly suggest a second host of instant Formula (1).
In analogous art, Parham teaches a compound for use as a matrix material in the emitting layer of an electronic device (paragraph 0106) which has very good properties on use in organic electroluminescent devices, in particular, on the lifetime, efficiency, and voltage (paragraph 0130).
Parham gives an example of the inventive compound in compound p18 (page 189), which is pictured below, and which meets the requirements of instant host material 1.
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This compound meets the requirements of instant Formula (1), when each X is nitrogen, each Y is oxygen, each X1 is CH, L and L1 are single bonds, R0 is a hydrogen atom, n is 3, m is 3, o is 3, and p is 3, Ar2 is an aryl group with 6 ring atoms, and Ar3 is also an aryl group with 6 ring atoms.
It would have been obvious to a person having ordinary skill in the art prior to the effective filing date of the claimed invention to use the matrix material of Parham as a second host in the mixture of Lee in order to achieve a mixture capable of producing an emission layer with very good properties, such as lifetime, efficiency, and voltage, when used in an organic electroluminescent device, as taught by Parham.
With respect to claim 29, Lee and Parham teach the mixture of claim 28, and Lee also teaches the mixture contains the phosphorescent emitter Ir(ppy)3, as discussed above.
With respect to claim 30, Lee and Parham teach the mixture of claim 28, as discussed above.
Parham also teaches that processing of compounds from the liquid phase, for example, by spin coating, requires formulations of the compounds such as solutions (paragraph 0097). As Lee teaches that the emission layer may be formed using spin coating (paragraph 0220), both Lee and Parham teach that the compounds may be processed from solution.
It would have been obvious to a person having ordinary skill in the art prior to the effective filing date of the claimed invention to include a solvent in the mixture of Lee and Parham in order to form an emission layer from solution via spin coating, as taught by Lee and Parham.
Claim 23 is rejected under 35 U.S.C. 103 as being unpatentable over Lee et al. (US 2015/0333273 A1) and further in view of Parham et al. (US 2017/0186965 A1) as applied above and further in view of Beers et al. (US 2014/0131676 A1).
With respect to claim 23, Lee and Parham teach the device of claim 22, as discussed above.
However, neither Lee nor Parham teach that the phosphorescent emitter has the structure of instant formula (III).
In analogous art, Beers teaches emitter compounds for use in organic light emitting devices (OLEDs) (abstract).
Beers gives an example of the claimed emitter compounds in Compound 1 (page 35), which is pictured below.
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Compound 1 meets the requirements of instant Formula (III) when one X is nitrogen and the rest are carbon atoms, n is 1 and m is 2. All R groups are hydrogen atoms.
Beers teaches that the claimed inventive iridium compounds result in lowered driving voltage, superior efficiency, and superior device stability when used as a material of the emitting layer of an organic light emitting device (paragraph 0079).
It would have been obvious to a person having ordinary skill in the art prior to the effective filing date of the claimed invention to use the compound of Beers as the phosphorescent emitting in the device of Lee and Parham in order to obtain a device with lowered driving voltage, superior efficiency, and superior device stability, as taught by Beers.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Parham et al. (US 2015/0340613 A1) – see compounds of formula (I-4) on page 13 which read on the instant second host.
Yamamoto et al (US 2013/0320310 A1) – teaches compound of the instant second host in combination with iridium dopants similar to instant claim 23.
Cho et al. (US 2019/0013490 A1) – teaches a dual host composition comprising similar host materials.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to RACHEL SIMBANA whose telephone number is (571)272-2657. The examiner can normally be reached Monday - Friday, 8:00 A.M. - 4:30 P.M..
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Jennifer Boyd can be reached at 571-272-7783. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/RACHEL SIMBANA/Examiner, Art Unit 1786
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