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 .
Response to Amendment
Claims 8, 10-11 and 16 have been cancelled; claims 1, 4-7, and 12-15 have been amended; and claims 1-7, 9, 12-15, and 17-20 are currently pending.
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.
Claims 1-7, 9, 12, 15, and 17-20 are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. (KR 20120070189 A, hereinafter “Kim”) in view of Thompson et al. (WO2016/014983 A1, hereinafter “Thompson”).
In regards to claim 1, Kim discloses (See, for example, Fig. 1) a device comprising: a first electrode (170);
a second electrode (160); and
an active layer (130) disposed between the first electrode (170) and the second electrode (160).
Kim fails to explicitly teach that the emissive stack comprising delayed fluorescent emitter; wherein a transient excited-state lifetime of the phosphorescent emissive material is not more than 200 ns.
Thompson while disclosing OLED device having enhancement layer teaches the emissive stack comprising delayed fluorescent emitter (“thermally activated delayed fluorescent material”, See par [0013]); wherein a transient excited-state lifetime of the phosphorescent emissive
material is not more than 200 ns (“An increase in the emission rate constant of the emitter
will also reduce the average time the emitter spends in the excited state…”, See Par [0077];
“o summarize these observations, the rate constant of emission for an OLED emitter, when
an enhancement layer is used, is strongly dependent on the emitter and device architecture.
A light emitting material positioned 10 nm from the enhancement layer is expected to have
its excited state decay rate constant increase is on the order of a factor of 5 and to be closer
than either threshold distance. A typical phosphorescent emitter has an emission rate
constant between 1.25E7 to 2E5 1/s, the expected emission rate in the presence of the
enhancement layer is 6.25E7 to 1E6 1/s.”, See Par [0163]. These rates correspond to excited state lifetimes on the order of nanoseconds, well within 200ns).
Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the invention to modify Kim by Thompson because the reduced excited-state lifetime improves device durability and reduces triplet-triplet annihilation losses.
In regards to claim 2, Kim as modified above discloses an enhancement layer comprising a plasmonic material exhibiting surface plasmon resonance (See, for example, Par [0019]-[0020]), Thompson).
In regards to claim 3, Kim as modified above discloses the first electrode or the second electrode comprises the enhancement layer (See, for example, Pars [0100], [0103],-[0105], Thompson).
In regards to claim 4, Kim as modified above discloses the delayed fluorescent emitter is disposed within not more than a threshold distance of the enhancement layer (See, for example, Pars [0019]-[0020], [0061], [0064], and [0163], Thompson).
In regards to claim 5, Kim as modified above discloses the threshold distance is equal to a distance from the enhancement layer at which the total radiative decay rate constant of the
delayed fluorescent emitter is equal to the total non-radiative decay rate constant of the delayed fluorescent emitter (See, for example, Fig. 3, Pars [0064] and [0065], Thompson).
In regards to claim 6, Kim as modified above discloses the plasmonic material in the enhancement layer non-radiatively couples to the delayed fluorescent emitter and transfers excited state energy from the delayed fluorescent emitter to a non-radiative mode of
surface plasmon polaritons of the enhancement layer (enhancement layer comprises a plasmonic material … See, for example, Pars [0019]-[0020], [0054]-[0056], See also, Claims
26 and 58, Thompson).
In regards to claim 7, Kim as modified above discloses the enhancement layer increases the density of states of the delayed fluorescent emitter within a first spectral range (The
enhancement layer modifies the modes that the emitter experiences increasing the density of states over some spectral range., See Par [0074], Thompson), wherein the first spectral
range comprises a peak emission wavelength of the delayed fluorescent emitter (See, for
example, Par [0075], Thompson).
In regards to claim 9, Kim as modified above discloses the enhancement layer comprises a material selected from the group consisting of: Au, Ag, Mg, Al, Ir, Pt, Ni, Cu, W, Ta, Fe, Cr, Ga, Rh, Ti, Ca, Ru, Pd, In, Bi, a small organic molecule, a polymer, SiO.sub.2, TiO.sub.2,
Al.sub.2O.sub.3, an insulating nitride, Si, Ge, and stacks or alloys thereof (See, for example, Kim page 4; also See, Pars [0094] and [0096], Thompson).
In regards to claim 12, Kim as modified above the delayed fluorescent emitter has an emission peak in the range 440-500 nm (Blue emission falls within the 440-500 nm, See Par [158], Thompson).
In regards to claim 15, Kim as modified above discloses the c has an emission peak in the range 640-1000 nm ( “The enhancement layer increases the excited state decay rate constant of the emitter within the OLED. Near infrared phosphors suffer low
photo luminescent quantum yields due to the intrinsic non-radiative decay rate constant
being much larger than the radiative decay rate constant. If the enhancement layer
increases the non-radaitve decay constant to a value much larger than the intrinsic non-
radiative decay constant it will create an efficient near infrared OLED”, See Par [0147], Thompson).
In regards to claim 17, Kim as modified above discloses an outcoupling layer disposed in a stack with the emissive stack (an outcoupling layer disposed over the enhancement layer, wherein the outcoupling layer scatters the energy from the surface plasmon polaritons as photons to
free space; See Pars [0019]-[0020], [0056], [0115]-[0118], and Claims 25 and 58,
Thompson).
In regards to claim 18, Kim as modified above discloses the first electrode or the second electrode acts as an outcoupling layer for surface plasmons (See, Par [0086], “patterning of the enhancement layer can facilitate the outcoupling of the non-radiative mode of the surface
plasmon to air.”; enhancement layer can act as electrode/contact layer, See Pars [0100],
[0103]-[0105], Thompson).
In regards to claim 19, Kim as modified above discloses the outcoupling layer comprises nanoparticles (Pars [0122], “An embodiment of the outcoupling layer which may be periodic, quasi-periodic, or random is the suspension of micro- or nano- particles within a
host matrix.”; “…the outcoupling layer comprises a plurality of particles in a host
material, wherein the plurality of particles have a physical dimension smaller than the
wavelength of the light being emitted to free space. Preferably, the particles have a physical
dimension in the range of 50-800 nm”, See, for example, Par [0129]).
In regards to claim 20, Kim as modified above discloses the device is at least one type selected
from the group consisting of: a flat panel display, a computer monitor, a medical monitor, a television, a billboard, a light for interior or exterior illumination and/or signaling, a heads-up
display, a fully or partially transparent display, a flexible display, a laser printer, a telephone, a
mobile phone, a tablet, a phablet, a personal digital assistant (PDA), a wearable device, a laptop
computer, a digital camera, a camcorder, a viewfinder, a micro-display having an active area
with a primary diagonal of 2 inches or less, a 3-D display, a virtual reality or augmented reality
display, a vehicle, a video wall comprising multiple displays tiled together, a theater or stadium
screen, and a sign (the light emitting device can be implemented in a display device, an
indicator device, or an illumination system including a lamp or street lamp (See, Kim Page
7); and See also Par [0053], Thompson).
Claims 13-14 are rejected under 35 U.S.C. 103 as being unpatentable over Kim in view of Thompson as applied to claim 1 above, and further in view of Uoyama et al. (NPL document “Highly efficient organic light-emitting diodes from delayed fluorescence”, 13 DECEMBER 2012, Nature 492, VOL 492, pp. 234-240, hereinafter “Uoyama”)
In regards to claims 13 and 14, Kim as modified above discloses all limitations of claim 1 except that the delayed fluorescent emitter has an emission peak in the range 500-550 nm; and the delayed fluorescent emitter has an emission peak in the range 555-640 nm.
Uoyama discloses the delayed fluorescent emitter has an emission peak in the range 500-550 nm (See Fig. 3, page 236, for example, peak wavelength around 510 nm); and the delayed fluorescent emitter has an emission peak in the range 555-640 nm (See Fig. 3, page 236, for example, peak wavelength, for example, 600 nm).
Therefore, it would have been obvious to one having ordinary skill in the art before the effective filing date of the invention to modify Kim as modified by Thompson by Uoyama because TADF emitters achieve high internal quantum efficiency by harvesting triplet excitons.
Response to Arguments
Applicant’s arguments with respect to claims 1 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Conclusion
THIS ACTION IS MADE FINAL. 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.
Correspondence
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ERMIAS T WOLDEGEORGIS whose telephone number is (571)270-5350. The examiner can normally be reached on Monday-Friday 8 am - 5 pm E.S.T..
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Britt Hanley can be reached on 571-270-3042. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see http://pair-direct.uspto.gov. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative or access to the automated information system, call
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/ERMIAS T WOLDEGEORGIS/Primary Examiner, Art Unit 2893
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