DENSO CORPORATION

Patent Trials and Appeals Board

Oct 22, 2021

2020006420 (P.T.A.B. Oct. 22, 2021)

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.
15/742,148 01/05/2018 Mitsunobu NAKATOU RYM-2635-1705 9311
23117 7590 10/22/2021
NIXON & VANDERHYE, PC
901 NORTH GLEBE ROAD, 11TH FLOOR
ARLINGTON, VA 22203
EXAMINER
SUN, CAITLYN MINGYUN
ART UNIT PAPER NUMBER
1795
NOTIFICATION DATE DELIVERY MODE
10/22/2021 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):
PTOMAIL@nixonvan.com
pair_nixon@firsttofile.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte MITSUNOBU NAKATOU, KEIGO MIZUTANI,
TAKASHI ARAKI, and TADASHI NAKAMURA
Appeal 2020-006420
Application 15/742,148
Technology Center 1700
Before CHRISTOPHER C. KENNEDY, SHELDON M. MCGEE, and
JANE E. INGLESE, Administrative Patent Judges.
MCGEE, Administrative Patent Judge.
DECISION ON APPEAL
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 1–4, 6–9, and 11. We have jurisdiction.
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 parties in interest as Denso
Corporation and Kabushiki Kaisha Toyota Chuo Kenkyusho. Appeal Br. 3.
Appeal 2020-006420
Application 15/742,148

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CLAIMED SUBJECT MATTER
The claims are directed to electrodes used in gas sensors. Spec. ¶ 1;
Claims 1, 6 (Appeal Br. 19–21 (Claims Appendix)).
Independent claim 1, reproduced below, is illustrative of the claimed
subject matter:
1. A pump electrode for a gas sensor, formed on a target gas-
side surface of a solid electrolyte body having ion conductivity,
the target gas-side surface being exposed to a target gas to be
measured, the pump electrode decomposing oxygen contained in
the target gas into oxide ions by an electric power supplied to the
pump electrode, the oxide ions passing through the solid
electrolyte body and being discharged to a reference gas-side
surface of the solid electrolyte body which is arranged in
opposite in position to the target gas-side surface, wherein
the pump electrode is made of Pt-Au alloy and a solid
electrolyte made of ceramic material which is the same type of
ceramic material forming the solid electrolyte body,
a first noble metal area, a first solid electrolyte area, a first
mixture area and first pores are formed in the pump electrode,
and a cross section of the pump electrode is cut along a thickness
direction of the pump electrode, wherein Pt-Au alloy
aggregations are formed in the first noble metal area, solid
electrolyte aggregations are formed in the first solid electrolyte
area,
Pt-Au alloy and the solid electrolyte are mixed with each
other in a three-dimensional structure in the first mixture area,
the first mixture area has an area within a range of 30 to
90 % in an area without the first pores, and the first pores are
formed adjacent to the first mixture area, and
the first pores occupy a volume within a range of 20 to 50
volume% in the overall volume of the pump electrode.
Appeal 2020-006420
Application 15/742,148

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REJECTIONS
I. Claims 6–9 under 35 U.S.C. § 103 as unpatentable over
Kajiyama2 and Lawless,3 as evidenced by Oya4; and
II. Claims 1–4 and 11 under 35 U.S.C. § 103 as unpatentable over
Kajiyama, Skelton,5 and Lawless, as evidenced by Oya.
OPINION
We review the appealed rejections for reversible error based on the
arguments and evidence presented by Appellant. 37 C.F.R.
§ 41.37(c)(1)(iv); Cf. Ex parte Frye, 94 USPQ2d 1072, 1075 (BPAI 2010)
(precedential) cited with approval in In re Jung, 637 F.3d 1356, 1365 (Fed.
Cir. 2011) (explaining that even if the Examiner had failed to make a prima
facie case, “it has long been the Board’s practice to require an applicant to
identify the alleged error in the examiner’s rejections”).
We address the claims separately to the extent they are so argued by
Appellant.
Claim 1
The Examiner finds that Kajiyama discloses the pump electrode of
claim 1 except for the limitations requiring (1) the electrode to be made of a
Pt-Au alloy, (2) the first mixture area has an area within a range of 30 to
90% in an area without the first pores, and (3) the first pores occupy a

2 US 2015/0293051 A1, published Oct. 15, 2015.
3 US 6,592,731 B1, issued July 15, 2003.
4 US 2014/0311906 A1, published Oct. 23, 2014.
5 D.C. Skelton et al., “A surface-science-based model for the selectivity of
platinum-gold alloy electrodes in zirconia-based NOx sensors,” 96 Sensors
and Actuators B 46–52 (2003).
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Application 15/742,148

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volume within a range of 20 to 50 volume % in the overall volume of the
pump electrode. Final Act. 12–18.
To address difference (1), the Examiner turns to Skelton, which the
Examiner undisputedly finds discloses a Pt-Au alloy electrode. Final Act.
15–16. The Examiner undisputedly determines it would have been obvious
to use such an electrode in Kajiyama’s device. Id. at 16.
To address differences (2) and (3), the Examiner undisputedly
determines that the claimed “mixture area” and porosity volume ranges are
each result-effective variables. Final Act. 17–18. The Examiner determines
that it would have been obvious for the skilled artisan to optimize the
mixture area and porosity values “to reach a workable range as routine
experimentation.” Id.
Appellant argues that “Kajiyama does not consider the presence of
pores.” Appeal Br. 9. This argument is unpersuasive because it does not
address the totality of the art relied on by the Examiner, i.e., Kajiyama and
Lawless. Final Act. 7–8.
Appellant next argues that “Kajiyama and Lawless do not disclose and
suggest” the claimed first mixture area range. Appeal Br. 9. That is
unpersuasive because it fails to squarely address the rejection that was made
by the Examiner––namely the result-effective nature of the claimed first
mixture area range. Final Act. 7.
Appellant next contends that the cited references do not fully
appreciate problems in the art such as “not having a sufficient area and not
adequately providing oxygen decomposition, and [difficulty] forming the
first mixture area in view of manufactur[ing] constraints.” Appeal Br. 9.
That argument is unpersuasive because the prior art need not recognize the
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Application 15/742,148

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problems contemplated by the inventor to establish a prima facie case of
obviousness. See KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 419–20
(2007) (“In determining whether the subject matter of a patent claim is
obvious, neither the particular motivation nor the avowed purpose of the
patentee controls. . . . [A]ny need or problem known in the field of endeavor
at the time of invention and addressed by the patent can provide a reason for
combining the elements in the manner claimed.”); In re Lemelson, 397 F.2d
1006, 1009 (CCPA 1968) (“The use of patents as references is not limited to
what the patentees describe as their own inventions or to the problems with
which they are concerned. They are part of the literature of the art, relevant
for all they contain.”); see also In re Applied Materials, Inc., 692 F.3d 1289,
1297 (Fed. Cir. 2012) (explaining that “the prior art need not provide the
exact method of optimization for the variable to be result effective” but that
“[a] recognition in the prior art that a property is affected by the variable is
sufficient to find the variable result-effective.” (emphasis added)).
On this record, Appellant does not dispute that the claimed mixture
area and porosity limitations are each result-effective variables. Final Act.
7–8. These uncontested findings are sufficient to support the Examiner’s
reliance on an optimization rationale to establish a prima facie case of
obviousness against these ranges recited in claim 1. The burden now rests
with Appellant to demonstrate how the claimed ranges are critical or achieve
some unexpected result. See In re Woodruff, 919 F.2d 1575, 1578 (Fed. Cir.
1990) (“The law is replete with cases in which the difference between the
claimed invention and the prior art is some range or other variable within the
claims. These cases have consistently held that in such a situation, the
applicant must show that the particular range is critical, generally by
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showing that the claimed range achieves unexpected results relative to the
prior art range.”) (internal citations omitted).
This brings us to Appellant’s assertions of criticality and its reliance
on Figure 12 of the Drawings. Appeal Br. 10–12. Appellant asserts that
“when the porosity of the pump electrode (3) is within a range of 20 to 50
volume% . . . it is possible to maintain the current change ratio (α) to a small
value.” Id. at 10.
On this record, we are unpersuaded that Figure 12 evinces criticality
of the claimed subject matter. First, Appellant does not establish that the
data illustrated in Figure 12 pertains to a pump electrode made of a Pt-Au
alloy, much less the claimed Pt-Au alloy with a “first mixture area having an
area within a range of 30 to 90% in an area without the first pores.” In other
words, it is not clear whether the data at issue is commensurate in scope with
the claims on appeal. See In re Tiffin, 448 F.2d 791, 792 (CCPA 1971)
(“[O]bjective evidence of non-obviousness must be commensurate in scope
with the claims which the evidence is offered to support.”).
Moreover, Appellant does not explain why having a “small” output
current change ratio (e.g., a value around 1 as depicted in Figure 12) is
critical or would have been unexpected. See In re Geisler, 116 F.3d 1465,
1470 (Fed. Cir. 1997) (explaining that “[o]nly if the ‘results of optimizing a
variable’ are ‘unexpectedly good’ can a patent be obtained for the claimed
critical range” (quoting In re Antonie, 559 F.2d 618, 620 (CCPA 1977)). On
this point, we note that “[m]ere argument or conclusory statements in the
specification [that a certain result is unexpected] does not suffice.” In re De
Blauwe, 736 F.2d 699, 705 (Fed. Cir. 1994). Appellant’s discussion of
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Figure 12 falls short because it does not elaborate on what would have been
expected or unexpected by the skilled artisan. Appeal Br. 11–12.
Because Appellant fails to identify reversible error in the rejection of
claim 1, we sustain it, along with the rejection of claims 2–4 and 11 not
separately argued.
Claim 6
In rejecting claim 6, the Examiner undisputedly finds that Kajiyama
discloses the claimed reference electrode, but does not expressly disclose
“the second mixture area” and “second pores” limitations. Final Act. 3–8.
The Examiner undisputedly finds that “mixture area” and “porosity” are
result-effective variables which the skilled artisan would have optimized “to
reduce the electrode capacitance and enhance the detection accuracy” and
“to reach a workable range as routine experimentation.” Id. at 7–8.
Appellant argues that the cited references fail to teach or suggest the
claimed ranges recited in “the second mixture area” and “second pores”
limitations. Appeal Br. 13–14, 17. That argument is unpersuasive because
the Examiner acknowledges as much. Final Act. 7.
Next, Appellant argues that the prior art does not recognize or
appreciate the problems that the claimed ranges purportedly solve. Appeal
Br. 14–17. That argument fails here for the same reasons it failed with
respect to claim 1. KSR, 550 U.S. at 419–20; In re Lemelson, 397 F.2d at
1009; In re Applied Materials, Inc., 692 F.3d at 1297.
Finally, Appellant asserts that Figure 13 of the Drawings demonstrates
criticality of the reference electrode’s claimed range of porosity, i.e., the
“second pores occupy a volume within a range of 20 to 60 volume% in the
overall volume of the reference electrode.” Appeal Br. 15–16. We are
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unpersuaded of any criticality here for the same reasons as those identified
supra. Namely, Appellant has not established that the data illustrated in
Figure 13 pertains to the claimed subject matter. Indeed, the Specification
offers no details regarding the chemical makeup of the electrode used for the
data captured in Figure 13, or whether it has the claimed “second mixture
area” recited in claim 6. Spec. ¶ 53. And as with claim 1, Appellant offers
no explanation regarding why having a “small” output current change ratio
(e.g., a value at or below 1 as depicted in Figure 13) is critical or would have
been unexpected.
In view of these deficiencies, the Examiner’s rejection of claim 6 is
sustained, along with the rejection of claims 7–9 not separately argued.
CONCLUSION
The Examiner’s rejections are affirmed.
DECISION SUMMARY
Claims
Rejected
35 U.S.C. § Reference(s) / Basis Affirmed Reversed
6–9 103 Kajiyama, Oya,
Lawless
6–9
1–4, 11 103 Kajiyama, Oya,
Skelton, Lawless
1–4,11
Overall
Outcome
1–4, 6–9,
11

No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 1.136(a)(1)(iv).
AFFIRMED