PPG Industries Ohio, Inc.

Patent Trials and Appeals Board

Jun 25, 2020

15152936 - (D) (P.T.A.B. Jun. 25, 2020)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
15/152,936 05/12/2016 Maurizio Ballarino 13009278P1 4042
24959 7590 06/25/2020
PPG Industries, Inc.
IP Law Group
One PPG Place
39th Floor
Pittsburgh, PA 15272
EXAMINER
VETERE, ROBERT A
ART UNIT PAPER NUMBER
1712
NOTIFICATION DATE DELIVERY MODE
06/25/2020 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
ipdocket@ppg.com
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte MAURIZIO BALLARINO, FRANCESCA BRUNETTI,
MICHELA CAGLIANI, GIORGIO CARDONE, ALDO DI CARLO,
and GIUSEPPINA POLINO

Appeal 2019-004682
Application 15/152,936
Technology Center 1700
____________

Before JEFFREY R. SNAY, MICHAEL G. McMANUS, and
MERRELL C. CASHION, JR., Administrative Patent Judges.

McMANUS, Administrative Patent Judge.

DECISION ON APPEAL

Pursuant to 35 U.S.C. § 134(a), Appellant1 seeks review of the
Examiner’s decision to reject claims 1, 3–12, and 14–22. We have
jurisdiction under 35 U.S.C. § 6(b).
We affirm.

1 We use the word “Appellant” to refer to “applicant” as defined in 37
C.F.R. § 1.42. Appellant identifies the real party in interest as PPG
Industries Ohio, Inc. Appeal Brief dated Jan. 29, 2019 (“Appeal Br.”) 3.
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Application 15/152,936
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CLAIMED SUBJECT MATTER
The present application generally relates to organic photovoltaic
systems and processes for making such systems. Specification filed May 12,
2016 (“Spec.”) ¶ 3. The Specification teaches that when light of the
appropriate frequency strikes a semiconducting organic polymer
“delocalized π electrons are excited by the electromagnetic energy from the
polymer molecule’s highest occupied molecular orbital (HOMO) to the
lowest unoccupied molecular orbital (LUMO).” Id. ¶ 4. The Specification
further teaches that “[t]he effectiveness and efficiency of organic
photovoltaic systems at generating electricity depends in part on the ability
of the systems to extract the excited and dissociated electrons from the
photoelectric active material.” Id. ¶ 5. The Specification additionally
teaches that extraction of such electrons generally requires that the
electrodes have a work function that is sufficiently low to collect the
electrons from the LUMO energy level of the photoelectric active material.
Id.
The application at issue describes a process for producing a low work
function electrode where “[a]n ethoxylated polyethyleneimine (PEIE) layer
is spray coated over the electrode layer.” Id. ¶ 8. In the alternative, an
“optional metal oxide nanoparticle layer may be deposited over the electrode
layer and the PEIE layer spray coated over the metal oxide nanoparticle
layer.” Id.
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Claim 1 is illustrative of the subject matter on appeal and is
reproduced below with certain limitations bolded for emphasis:
A process for producing a photovoltaic system
comprising:
depositing a first electrode layer over a substrate;
spray coating a metal oxide nanoparticle layer over
the first electrode layer;
spray coating an ethoxylated polyethyleneimine
(PEIE) layer over the metal oxide nanoparticle layer;
depositing a bulk heterojunction active layer over the
PEIE layer; and
depositing a second electrode layer over the bulk
heterojunction active layer.
Appeal Br. 26 (Claims App.) (reformatted for clarity) (emphasis added).
REFERENCES
The Examiner relies upon the following prior art:
Name Reference Date
Mano US 4,229,838 Oct. 28, 1980
Wakata US 2002/0064633 A1 May 30, 2002
Hasegawa US 2003/0108751 Al June 12, 2003
Brabec US 2007/0181179 Al Aug. 9, 2007
Jen US 2009/0188558 A1 July 30, 2009
Taillemite US 2013/0283794 A1 Oct. 31, 2013
Li-Min Chen et al., Multi-Source/Component Spray Coating for Polymer
Solar Cells, ACSNANO Vol. 4, No. 8, 4744–4752 (2010).
Yinhua Zhou et al., A Universal Method to Produce Low-Work Function
Electrodes for Organic Electronics, Science Vol. 336, 327–332 (2012).
Jae Won Shim et al., Studies of the optimization of recombination layers
for inverted tandem polymer solar cells, Solar Energy Materials & Solar
Cells 107, 51–55 (2012).

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REJECTIONS
The Examiner maintains the following rejections:
1. Claims 1, 3, 7, 12, 14, 21, and 22 are rejected under 35 U.S.C.
§ 103 as being unpatentable over Shim in view of Chen and
Jen. Final Action dated Sept. 25, 2018 (“Final Act.”) 3–4.
2. Claims 4, 5, 15, and 16 are rejected under 35 U.S.C. § 103 as
being unpatentable over Shim in view of Chen, Jen, and
Taillemite. Id. at 4.
3. Claims 6, 8, 17, and 19 are rejected under 35 U.S.C. § 103 as
being unpatentable over Shim in view of Chen, Jen, and Zhou.
Id. at 4–5.
4. Claims 9 and 18 are rejected under 35 U.S.C. § 103 as being
unpatentable over Shim in view of Chen, Jen, Zhou, and
Hasegawa. Id. at 5.
5. Claim 10 is rejected under 35 U.S.C. § 103 as being
unpatentable over Shim in view of Chen, Jen, Zhou, and
Brabec. Id. at 5–6.
6. Claims 11 and 20 are rejected under 35 U.S.C. § 103 as being
unpatentable over Shim in view of Chen, Jen, Zhou, Wakata,
and Mano. Id. at 6.
DISCUSSION
Rejection 1. The Examiner rejects claims 1, 3, 7, 12, 14, 21 and 22 as
obvious over Shim in view of Chen and further in view of Jen. Id. at 3–4.
In support of the rejection, the Examiner finds that Shim teaches forming a
solar cell by depositing an indium-tin oxide (ITO) electrode on a glass
substrate, coating a polyethyleneimine ethoxylated (PEIE) layer directly
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over the ITO electrode, depositing a bulk heterojunction layer over the PEIE
layer, and depositing a silver electrode over the bulk heterojunction. Id. at 3.
The Examiner finds that Shim fails to teach 1) that the PEIE layer is applied
by spray coating and 2) that a metal oxide nanoparticle layer is applied to the
first electrode. Id. at 3–4.
The Examiner finds that Chen teaches a method of forming a polymer
solar cell and explains that the layers of the cell can be applied via spray
coating. Id. at 3. The Examiner determines that one of ordinary skill in the
art would have had reason to use the spray coating of Chen to deposit the
PEIE layer of Shim “in order to have applied a large-area uniform film with
the predictable expectation of success.” Id. at 3–4.
The Examiner further finds that Jen teaches a process of making a
solar cell that “includes depositing a layer of zinc oxide nanoparticles onto
the first electrode in order to improve the work function of the electrode.”
Id. at 4. The Examiner determines that one of ordinary skill in the art would
have had reason to use a layer of zinc oxide nanoparticles on the first
electrode of Shim in order to have improved the work function of the
electrode. Id.
Appellant alleges error on several bases. We first address Appellant’s
arguments regarding the Examiner’s prima facie case and next consider its
arguments regarding criticality.

Spray Coating
Appellant argues that the references do not teach to spray coat an
ethoxylated PEIE layer over a metal oxide nanoparticle layer. Appeal Br. 9–
13. The Specification provides the following definitions of “spray coating”
and “spin coating”:
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Spray coating – “a coating process comprising atomizing
or aerosolizing a liquid coating composition in a compressed gas
stream functioning as a carrier medium that propels the coating
composition, targeting the carrier gas comprising the coating
composition into contact with a substrate, and depositing the
coating composition from the carrier gas stream onto the
substrate forming a coating layer.”

Spin coating – “a batch process requiring the use of
specialized equipment that spins the deposition substrate to
spread the coating material by centrifugal force.”

Spec. ¶¶ 26–27.
Appellant points out that Shim teaches to apply the PEIE layer by spin
coating rather than spray coating. Appeal Br. 9; Shim 52 (“A 10 nm-thick
PEIE layer was spin casted onto the substrates in air.”). Appellant further
points out that Jen does not teach a PEIE layer. Appeal Br. 9. Appellant
asserts that, although Chen teaches spray coating of certain polymer
coatings, it does not “teach or suggest a PEIE layer, let alone that PEIE can
be spray coated.” Id. at 10.
Chen teaches, in part, as follows:
Spin-coating is the dominant fabrication method in
polymer solar cell research; however, it is neither high
throughput nor scalable. To realize these requirements, a
myriad of deposition methods such as inkjet printing, screen
printing, doctor blading, and spray coating have all been
adopted to pursue success in large area coating. Amongst them,
spray coating is capable of delivering large-area, uniform
large polymer thin films through a relatively simple process,
offering ample processing possibilities of engineering the
film structure. In this method, the film evolution is a
reconstitution process whereby solution particles are atomized
and driven by a carrier gas onto the substrate; therefore, the
droplets and resulting domain sizes can be finely tuned via
controlled atomization. Films with a broad range of
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concentration and composition can be delivered via the
spray coating method, thus allowing for the straightforward
processing of polymers with poor solubility, as well as organic
and inorganic materials with varying degrees of
solubility/dispersity in the liquid phase. This opens up a whole
new category of applications in materials chemistry.

Chen 4744. Appellant quotes brief portions of Chen regarding film drying
time and dissolution of the film underlayer without clear explanation as to
such teaching’s applicability to spray coating of PEIE. Appeal Br. 10, 16.
Appellant additionally argues that spin casting and spray coating are
non-interchangeable processes. Id. at 10. In support, Appellant asserts that
“spin casting is limited to very flat surfaces and cannot coat a rough surface
effectively” while spray casting can coat a rough surface. Id. Appellant
cites the Specification’s teaching that “multi-layer spray coating process
avoids the functional surface area constraints imposed by other deposition
techniques, such as spin [casting], for example, and may be used to produce
large-area organic photovoltaic systems with relatively high through-put.”
Id. at 10–11 (Spec. ¶ 22). This is not persuasive of nonobviousness. The
foregoing distinctions merely point out the known advantages of spray
coating. These factors tend to weigh in favor of one of ordinary skill in the
art having reason to employ spray coating.
Appellant further submits evidence that “the formulation of the PEIE
layer as disclosed in Shim could not be spray coated by the process of Chen
and achieve repeatable and sufficient adhesion to the underlayer.” Id. at 11
(citing the Declaration of Giorgio Cardone (hereinafter “Cardone
Declaration”)). This is not persuasive. The Examiner finds that “it is well
understood in the art that any solution, having its viscosity properly adjusted,
is suitable for spraying.” Examiner’s Answer dated March 19, 2019
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(“Answer”) 4. The Examiner further finds that it is known to make
appropriate adjustments. As the Examiner explains in the Answer,
[t]he [E]xaminer is not suggesting that the spin coating step of
Shim be simply replaced with spraying and nothing else must
change. A person of ordinary skill in the art, looking at Chen,
would have understood that spray coating involves additional
considerations to provide satisfactory results and would have
included these additional considerations in any process
modified to use spray coating.

Answer 4. Further, as the Examiner observes, “the declaration does not
provide any evidence concerning PEIE.” Id. at 5. Accordingly, Appellant’s
argument that “formulations for PEIE used for spin casting may not be able
to be spray coated” is not persuasive.

PEIE Layer over the Metal Oxide Layer
Appellant argues that the cited references do not teach to apply a PEIE
layer over a metal oxide nanoparticle layer. Appeal Br. 13–14. The
Examiner finds that Shim teaches to apply a PEIE layer to an electrode
layer. Final Act. 3. The Examiner further finds that Jen teaches to deposit a
layer of zinc oxide nanoparticles onto the first electrode layer to improve the
work function of the electrode. Id. at 4. The Examiner concludes that one
of ordinary skill in the art would have had reason “to have deposited a layer
of zinc oxide nanoparticles on the first electrode of Shin before depositing
the PEIE layer (i.e. and therefore depositing the PEIE layer directly onto the
nanoparticle layer) in order to have improved the work function of the
electrode.” Id.
Appellant argues that the Examiner’s conclusion is “unsupported and
conclusory.” Appeal Br. 13. Appellant contends that the references
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“applied separately or in combination do not teach or suggest how (e.g.,
which order) to apply both a PEIE layer and a metal oxide nanoparticle
layer.” Id. at 14. Appellant further directs us to Jen’s teaching that the
metal oxide nanoparticle layer can be intermediate the electron-conducting
electrode and the monolayer or intermediate the photovoltaic layer and the
monolayer. Id. (citing Jen ¶ 46). In view of such teachings, Appellant
contends that “the record is devoid of any teaching or suggestion of the order
in which a PEIE layer and a metal oxide nanoparticle layer would be
applied.” Id.
This is not persuasive. Jen teaches an embodiment where a thin layer
of ZnO nanoparticles are spin-coated onto the electrode. Jen ¶ 129. The
Examiner may rely on such teaching. See Merck & Co., Inc. v. Biocraft
Labs., Inc., 874 F.2d 804, 807 (Fed. Cir. 1989) (“[A]ll disclosures of the
prior art, including unpreferred embodiments, must be considered.”). In the
Answer, the Examiner concludes that “Jen explains that forming the zinc
oxide nanoparticle layer onto the first electrode improves the work function
of the electrode and it would have been obvious . . . to have incorporated this
featured into Shim in order to have improved the work function of the
electrode.” Answer 6. Appellant has not shown error in such reasoning.

Reasonable Expectation of Success
Appellant further argues that the Examiner has not adequately shown
that the results of the proposed combination would have been predictable.
Appeal Br. 15–18. Appellant contends that the Examiner has not adequately
addressed differences in the drying time of a PEIE layer that is spin cast as
opposed to spray coated and the resulting differences in work function of the
electrode. Id. at 16. Appellant further contends that Chen (which the
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Examiner relies on to teach spray coating) does not teach the spray coating
of a PEIE layer. Id. at 17.
In the Answer, the Examiner reasons that “one of ordinary skill in the
art would have understood the results [of the combination] to be predictable
because one of ordinary skill in the art would have understood the variables
involved.” Answer 8. The Examiner further determines that “Chen teaches
that the polymer layers in a solar cell (such as Shim’s PEIE) can be spray
coated instead of spin casted. Thus, the intended purpose of forming a
functional solar cell would have worked in this combination.” Id.
Appellant has not shown error in the Examiner’s reasoning. As our
reviewing court has explained, “[o]bviousness does not require absolute
predictability of success. . . . For obviousness under § 103, all that is
required is a reasonable expectation of success.” In re Kubin, 561 F.3d
1351, 1360 (Fed. Cir. 2009). Here, the Examiner has put forward a reasoned
basis as to why a person of ordinary skill in the art would have been
motivated to use a spray coating method and to apply a metal oxide layer to
an electrode. Appellant directs us to certain differences between the
processes, such as drying time, but does not show error in the Examiner’s
finding that, in view of Chen’s teachings regarding the general applicability
of spray coating and Jen’s teaching regarding application of a zinc oxide to
an electrode, one of skill in the art would have determined that such
combination had at least a reasonable expectation of success.
In view of the foregoing, we determine that Appellant has not shown
error in the Examiner’s prima facie case of obviousness of claims 1, 3, 7, 12,
14, 21, and 22 (subject to Rejection 1).

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Unexpected Benefits
Appellant additionally argues that the claimed method yields
unexpected benefits. Appeal Br. 11–12 (regarding claims 1 and 12), 14
(regarding claims 1 and 12), 19 (regarding claims 21 and 22), and 20–21
(regarding claims 3 and 14).
Appellant argues that the inventors discovered “several unexpected
alterations in the application of PEIE that could positively affect uniform
surface coverage and electrical efficiency of the photovoltaic system
utilizing spray coating.” Id. at 11. Appellant argues that the addition of a
zinc oxide nanoparticle layer between the electrode and the PEIE layer
improved the charge transport of the photovoltaic system. Id. In support of
these assertions, Appellant refers to the Cardone Declaration. The Cardone
Declaration includes the following statements:
“[I]t was surprisingly found that . . . . the addition of a zinc
oxide nanoparticle layer between the electrode prior and the
PEIE or bulk heterojunction active layer resulted in more
uniform surface coverage by the PEIE and bulk heterojunction
active layer and improved the charge transport of the
photovoltaic system.”

Cardone Declaration ¶ 9.
“It was surprisingly found that the zinc oxide nanoparticle layer
improved the surface coverage of the PEIE layer and bulk
heterojunction layer on the electrode layer.”

Id.
“[I]t it was surprisingly found that a spray coated zinc oxide
nanoparticle layer had improved electrical efficiency and a spin
coated zinc oxide nanoparticle layer negatively affected the
electrical efficiency of the photovoltaic system.”

Id. ¶ 11.
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The Examiner finds this showing not to be commensurate with the
scope of claim 1 as “claim 1 is more broadly directed to metal oxides, not
the limited species of zinc oxides.” Final Act. 2. The Examiner further
determines that “the only statements in the declaration directed to the
surprising results associated with the metal oxide layer (§ 9, 10, and 11 of
the declaration) are merely conclusory statements which provide no
evidence to support them.” Answer 9. The Examiner makes a similar
determination regarding statements in the declaration regarding claims 3 and
14. Id.
In general, an applicant may overcome a prima facie case of
obviousness by establishing that a claimed feature “is critical, generally by
showing that the claimed range achieves unexpected results relative to the
prior art.” In re Geisler, 116 F.3d 1465, 1469–70 (Fed. Cir. 1997) (citation
omitted). “Although it is well settled that comparative test data showing an
unexpected result will rebut a prima facie case of obviousness, the
comparative testing must be between the claimed invention and the closest
prior art.” In re Fenn, 639 F.2d 762, 765 (CCPA 1981). Moreover, “[i]t is
well settled that unexpected results must be established by factual evidence.
Mere argument or conclusory statements in the specification does not
suffice.” In re De Blauwe, 736 F.2d 699, 705 (Fed. Cir. 1984), quoted with
approval in In re Soni, 54 F.3d 746, 750 (Fed. Cir. 1995).
We agree with the Examiner that the scope of the Declaration is not
commensurate with the claims (other than claims 3 and 14) because the
Declaration is limited to a zinc oxide nanoparticle layer while most of the
claims require only a metal oxide nanoparticle layer. Further, Appellant
fails to supply comparative test data. Appellant does not supply data for the
inventive process (nor for a product made by such process) nor for the
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closest prior art. Accordingly, Appellant has not shown adequate evidence
of unexpected results sufficient to establish the criticality of the claimed
process.
In view of all of the foregoing, Appellant has not shown error with
regard to the rejection of claims 1, 3, 7, 12, 14, 21, and 22.

Rejections 2 and 3. The Examiner rejects claims 4, 5, 15, and 16 as
obvious over Shim in view of Chen, Jen, and Taillemite. Final Act. 4
(Rejection 2). The Examiner additionally rejects claims 6, 8, 17, and 19 as
obvious over Shim in view of Chen, Jen, and Zhou. Id. at 4–5 (Rejection 3).
Appellant alleges error in these rejections on the same basis as with regard to
Rejection 1. Appeal Br. 6. As we have not found such arguments to be
persuasive, we determine that Appellant has not shown error with regard to
claims 4, 5, 6, 8, 15–17, and 19.

Rejection 4. The Examiner rejects claims 9 and 18 as obvious over
Shim in view of Chen, Jen, Zhou, and Hasegawa. Final Act. 5. Claim 9
depends from claim 8 and further requires that “the spray coated silver
layers are formed from the reaction products of a Tollens’ reaction.” Appeal
Br. 27 (Claims App.). Claim 18 is similar. Id. at 28.
The Examiner finds that Zhou teaches that silver is a suitable material
for an electrode and Hasegawa teaches a method of forming a silver layer
wherein the silver is formed from a Tollens’ reaction. Final Act. 5.
Appellant argues that “it was surprisingly discovered that the reactants
for the Tollens’ reaction could be spray coated and would begin to react as
the formulation was being sprayed onto a surface to form the silver layer.”
Appeal Br. 21. As a consequence, “the silver layer could be dried at room
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temperature without baking the electrode in an oven which can be
advantageous for large format electrodes.” Id. at 21–22. In support of this
argument, Appellant relies on the Cardone Declaration.
The Cardone Declaration states that commercially available silver
pastes are not suitable for spray coating due to their viscosity. Cardone
Declaration ¶ 12. The Declaration further states as follows:
It was surprisingly discovered that the reactants for the Tollens’
reaction could be spray coated and would begin to react as the
formulation was being sprayed onto a surface to form the silver
layer. Thereafter, the silver layer could be dried at room
temperature without baking the electrode in an oven which can
be advantageous for large format electrodes.
Id.
The Specification teaches “a Tollens’ reaction in which silver nitrate
in an aqueous ammonia solution is reduced to silver metal during the
spraying by reaction with an aldehyde-containing compound.” Spec. ¶ 32.
The Specification further teaches that “[t]he spray coating of metallic silver
layers is generally described, for example, in European Patent Publication
Nos. 0 346 954 A2 and 1 469 099 A1, which are both incorporated by
reference into this specification.” Id. In addition, Hasegawa, relied on by
the Examiner, teaches formation of a silver plate layer. Hasegawa ¶ 79.
Specifically, Hasegawa teaches “an ammoniac silver nitrate (Ag(NH3)2+OH-)
solution (Tollens’ reagent) and a reducing agent solution are applied onto the
surface of the basecoat layer 13 while they are mixed thereon to induce
redox reaction to thereby deposit the metal silver (Ag) to form the metal
plate layer.” Id.
As above, an unexpected result must be shown by comparative testing
between the claimed invention and the closest prior art. Further, conclusory
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statements are insufficient. The Specification indicates that the spray
coating of metallic silver layers is known in the art. This is consistent with
the cited prior art. Neither Appellant’s brief nor the Declaration presents
comparative data (or substantive discussion) regarding prior art spray
coating of metallic silver layers (or relevant drying characteristics) and that
of the claims. Accordingly, Appellant has not shown that a process for the
formation of a spray coated silver layer from the reaction products of a
Tollens’ reaction yields an unexpected benefit commensurate with the
claims.

Rejection 5. The Examiner rejects claim 10 as obvious over Shim,
Chen, Jen, and Zhou in light of Brabec. Final Act. 5–6. Appellant alleges
error on the same basis as with regard to Rejection 1. Appeal Br. 6. As we
have not found such arguments to be persuasive, we determine that
Appellant has not shown error with regard to claim 10.

Rejection 6. The Examiner rejects claims 11 and 20 as obvious over
Shim, Chen, Jen and Zhou in light of Wakata and Mano. Final Act. 6.
Claim 11 depends from claim 1 and further requires that the PEIE
formulation “is spray coated using a formulation consisting of PEIE, water,
and optionally ethanol, 2-propanol, or isopropanol, or any combination of
ethanol, 2-propanol, or isopropanol wherein the formulation is substantially
free of methoxyethanol.” Appeal Br. 27 (Claims App.). Claim 20 depends
from claim 12 and is similar in scope. Id. at 28.
The Examiner finds that Chen teaches that “spraying polymers is done
from a dispersion.” Final Act. 6. The Examiner further finds that Wakata
teaches that water is a suitable dispersing agent for spraying polymers to
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form a layer. Id. (citing Wakata ¶ 139). The Examiner additionally finds
that Mano teaches that suitable solvents for PEIE include water combined
with methanol or ethanol. Id. (citing Mano, col. 4:64–5:12). In view of the
foregoing, the Examiner determines that it would have been obvious to
employ a formulation of methanol or ethanol in combination with aqueous
PEIE. Id.
Appellant argues that one of ordinary skill in the art would not have
had reason to combine the teachings of Mano with those of Shim and Chen.
Appeal Br. 23. Appellant argues that Mano is directed to “an antithrombic
vascular prosthesis” and does not teach or suggest spray coating. Id.
Appellant further asserts that “[t]here is no[] teaching or suggestion in the
prior art of record that methoxyethanol could be removed from Shim’s PEIE
layer and achieve the desired work function or that one of ordinary skill in
the art would [remove] methoxyethanol from Shim’s PEIE layer.” Id.
The Examiner determines that the use of methanol or ethanol (as
taught by Mano) as a solvent for PEIE is the mere “simple substitution of
one known element for another to obtain predictable results.” Final Act. 6.
Appellant does not show error in, or even squarely address, this
determination.
Appellant additionally argues that Wakata is not analogous art.
Appeal Br. 23–24. Appellant argues that Wakata is from a different field of
endeavor and, additionally, is not reasonably pertinent to the problem at
issue. Id. Appellant similarly argues that Mano is neither from the same
field of endeavor as Appellant’s claims nor pertinent to the problem faced by
the Appellant. Id.
References qualify as prior art for an obviousness determination only
when analogous to the claimed invention. In re Clay, 966 F.2d 656, 658
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(Fed. Cir. 1992). Two separate tests define the scope of analogous prior art:
(1) whether the art is from the same field of endeavor, regardless of the
problem addressed and, (2) if the reference is not within the field of the
inventor’s endeavor, whether the reference still is reasonably pertinent to the
particular problem with which the inventor is involved. In re Deminski, 796
F.2d 436, 442 (Fed. Cir.1986); see also In re Wood, 599 F.2d 1032, 1036
(CCPA 1979).
Here, the inventors indicate that “[t]he thickness and density of a
spray coated PEIE layer may be controlled by setting the spray coating
process parameters, including . . . the composition of the PEIE coating
solution (e.g., solvent composition, PEIE concentration, and the like).”
Spec. ¶ 28. The Specification further teaches that “[t]he aqueous
formulation used for spray coating a PEIE layer according to the present
invention may include a non-toxic alcohol co-solvent or additive such as, for
example, ethanol or isopropanol.” Id. ¶ 29 (emphasis added). Similarly, the
Specification teaches that
[a]n aqueous formulation for spray coating a PEIE layer used in
accordance with the present invention may consist of PEIE and
water. Alternatively, an aqueous and/or alcohol-based
formulation for spray coating a PEIE layer may consist of
PEIE, water, and isopropanol, for example, or may consist of
PEIE, water, and ethanol, for example.
Id. Thus, the Specification addresses spray coating process parameters.
The Examiner finds that Wakata teaches that water is a suitable
dispersing agent for spraying polymers used to form a layer. Final Act. 6
(citing Wakata ¶ 139). Wakata teaches that
a method of applying the coating solution (second coating
solution) containing the polymer according to the present
invention which is prepared in the form of a water dispersion . .
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. include . . . a method of atomizing the second coating solution
by a spraying method or the like.
Wakata ¶ 139. Wakata’s teaching regarding use of water as a dispersing
agent for spraying polymers to form a layer is reasonably pertinent to the
inventors’ stated problem of controlling the spray coating process
parameters.
The Examiner additionally finds that Mano is analogous art because it
is reasonably pertinent to the particular problem with which the inventor is
involved. Answer 9. More specifically, the Examiner finds that Mano
concerns forming a PEIE solution. Id.
We look to the cited portion of Mano to determine if it is reasonably
pertinent. Mano teaches that “[w]ater is suitable as a solvent for the
polyethyleneimine” (Mano, col. 4:64–65) and “[s]ince polyethyleneimine is
also soluble in a lower alcohol such as methanol, ethanol or ethylene glycol,
the polyethyleneimine may be dissolved in such a solvent and the porous
tubing can be impregnated directly with such a solution” (id. at col. 5:8–12).
Thus, while Mano and the present application may be from different
fields of endeavor, both address PEIE solutions. Accordingly, the
Examiner’s determination that Mano is reasonably pertinent to the problem
faced by the inventors, and therefore analogous art, is consistent with record
evidence.

Appeal 2019-004682
Application 15/152,936
19
CONCLUSION

For the reasons set forth in the Final Action, the Examiner’s Answer,
and above, the Examiner’s rejections are affirmed.
In summary:
Claims
Rejected
35 U.S.C.
§
Reference(s)/Basis Affirmed Reversed
1, 3, 7, 12,
14, 21, 22
103 Shim, Chen, Jen 1, 3, 7, 12,
14, 21, 22

4, 5, 15, 16 103 Shim, Chen, Jen,
Taillemite
4, 5, 15, 16
6, 8, 17, 19 103 Shim, Chen, Jen,
Zhou
6, 8, 17, 19
9, 18 103 Shim, Chen, Jen,
Zhou, Hasegawa
9, 18
10 103 Shim, Chen, Jen,
Zhou, Brabec
10
11, 20 103 Shim, Chen, Jen,
Zhou, Wakata,
Mano
11, 20
Overall
Outcome
1, 3–12,
14–22

No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).

AFFIRMED