Ex Parte Watakabe

Board of Patent Appeals and Interferences

Jun 22, 2009

10640022 (B.P.A.I. Jun. 22, 2009)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte ATSUSHI WATAKABE
____________

Appeal 2009-003568
Application 10/640,022
Technology Center 1700
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Decided: 1June 22, 2009
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Before CHUNG K. PAK, KAREN M. HASTINGS, and
MICHAEL P. COLAIANNI, Administrative Patent Judges.

HASTINGS, Administrative Patent Judge.

DECISION ON APPEAL

1 The two-month time period for filing an appeal or commencing a civil
action, as recited in 37 C.F.R. § 1.304, begins to run from the Decided Date
shown on this page of the decision. The time period does not run from the
Mail Date (paper delivery) or Notification Date (electronic delivery).

Appeal 2009-003568
Application 10/640,022

Appellant appeals under 35 U.S.C. § 134(a) from the Examiner’s final
rejection of claims 1, 8, 10, and 11. An oral hearing was held on June 9,
2009. We have jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM.
STATEMENT OF THE CASE
The invention relates to a polymeric electrolyte material for use as a
fuel cell (Spec. 1:5-9). Claim 1 is illustrative:
1. An electrolyte material for a polymer electrolyte fuel
cell, which is made of a copolymer comprising repeating units based
on a monomer of the formula (1) and repeating units based on
tetrafluoroethylene and which has an ion exchange capacity of from
1.0 to 1.5 (meq/g dry resin):

CF2=CFCF2OCF2CF2SO3H (1)

The Examiner rejected claims 1, 8, 10, and 11 under 35 U.S.C. §
103(a) as being unpatentable over the combined teachings of Uchida2 and
Krespan3.
Appellant has not separately argued any of the claims with any
reasonable degree of specificity (App. Br. 3-8). Accordingly, we select
claim 1 as representative and confine our discussion to this selected claim.
The Examiner relies upon Uchida as teaching that a fuel cell
electrolyte membrane may be made of a polymer having repeating units of
tetrafluoroethylene (i.e., TFE) and a perfluorovinyl compound having a
sulfonic acid group of formula CF2=CFO(CF2) qSO3H, wherein q is an

2 (US 2002/0144394 A1, published Oct. 10, 2002)
3 (US 4,273,729, published June 16, 1981)
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Application 10/640,022

integer from 1 to 8 and should have an ion exchange capacity of from 0.5 to
4.0 meq/g dry resin (Ans. 5). The Examiner’s position is that:
Furthermore, Krespan teaches a copolymer comprising
repeating units based on a monomer CF2=CFCF2OCF2CF2SO2F
and repeating units based on a monomer such as
tetrafluoroethylene [TFE] to form polymers which are
moldable, and in some cases electrically conducting or are
water-wettable and dyeable (abstract). Tetrafluoroethylene is
especially preferred (11:18-19). The monomer
CF2=CFCF2OCF2CF2SO2F may be hydrolyzed to a copolymer
bearing SO2OH groups [SO3H]. An important feature of a
CF2=CFCF2OCF2CF2SO2F (polyfluoroallyloxy) comonomer
bearing SO2OH groups is the capacity for ion exchange (11:35-
63). The ion exchange copolymer may be used in the form of a
film membrane to separate the anode and cathode portions of a
cell (11:68-12:2).
The invention as a whole would have been obvious to one
having ordinary skill in the art at the time the invention was
made because one of skill would have known the perfluorovinyl
compound having a sulfonic acid group of Krespan could have
been used as the perfluorovinyl compound having a sulfonic
acid group disclosed by Uchida. Both references are directed
toward polymer electrolyte materials.
(Ans. 4)
ISSUE ON APPEAL
Appellant contends that the “heart of [his] argument as detailed in the
Appeal Brief” is that “there was no known practical method” for obtaining a
polymer comprising a sufficient percentage of repeating units based on
monomer (1) to achieve the minimum ion capacity of 1.0 meq/g dry resin as
recited in claim 1 (Reply Br. 2, 3; emphasis added).
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Application 10/640,022

Has Appellant shown that the Examiner reversibly erred in rejecting
product claim 1 as obvious over the combined teachings of Uchida and
Krespan because of Appellant’s contention that there was no “practical
method” for obtaining the ion-exchange capacity claimed of the polymer?
We answer this question in the negative.
PRINCIPLES OF LAW
The test for obviousness is what the combined teachings of the
references would have suggested to those of ordinary skill in the art. In re
Young, 927 F.2d 588, 591 (Fed. Cir. 1991); In re Keller, 642 F.2d 413, 425
(CCPA 1981).
The combination of familiar elements according to known methods
would likely have been obvious when it does no more than yield predictable
results. KSR Int’l Co. v. Teleflex, Inc., 550 U.S. 398, 416 (2007). The
question to be asked is “whether the improvement is more than the
predictable use of prior-art elements according to their established
functions.” Id. at 417.
FINDINGS OF FACTS
Findings of fact throughout this opinion are supported by a
preponderance of the evidence.
Uchida exemplifies that an ion exchange capacity between 0.5 to as
high as 4.0, more preferably from 0.7 to 2.0, meq/g dry resin, are desirable
for an ion-exchange membrane in a fuel cell (p. 6, para. [0055]). Uchida
describes a polymer based on repeating units of tetrafluoroethylene (TFE)
and a perfluorovinyl compound having a sulfonic acid group which
preferably may be CF2=CFO(CF2) qSO3H, wherein q is an integer from 1 to
8. Uchida’s perfluorovinyl compound of CF2=CFO(C F2) qSO3H differs
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Application 10/640,022

from the claimed perfluorovinyl compound by the addition of one internal
CF2 group located prior to the oxygen.
Appellants do not dispute that Krespan describes an electrolyte
polymer material comprising monomer of formula (1) and TFE as claimed
(Ans. 4; Krespan, abstract; col. 11, ll. 18-20, col. 11, l. 68 to col. 12, l. 4, see
generally App. Br.; Reply Br.), except that Krespan does not explicitly
describe the ion exchange capacity of from 1.0 to 1.5 meq/g dry resin as
claimed.
Appellant does not dispute that Krespan describes hydrolyzing such a
polymer with regards to copolymers having about 1 to 10 mol percent of the
polyfluoroallyloxy comonomer along with its pendant -SO2F group to the
required -SO3F (Krespan, col. 11, ll. 49-63; App. Br. 5).
Krespan describes that hydrolyzing the -SO2F groups to -SO3F results
in the “capacity for ion exchange” (col. 11, ll. 58-63), so as to be useful as a
film membrane in a fuel cell (col. 11, l. 64 to col. 12, l. 4).
Krespan also describes copolymers with up to 25 mole percent of the
polyfluoroallyloxy monomer (col. 11, ll. 35-37), but does not explicitly
describe hydrolyzing the pendant -SO2H groups to -SO3H groups when up
to 25 mole percent of the monomer is used so as to make these copolymers
useful as an ion-exchange electrolyte material.
Appellant contends the polymer of Krespan does not have the claimed
ion exchange capacity because there is an insufficient amount of the
hydrolyzed polyfluoroallyloxy comonomer (App. Br. 5).
Appellant has provided evidence that such a polymer with up to 10
mole percent of the comonomer with pendant –SO2H groups has an ion
exchange capacity of .85 meq/g dry resin (App. Br. 5, 6).
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Application 10/640,022

Appellant does not dispute that one of ordinary skill in the art would
have known that use of a greater mole percentage of formula (1) monomer
with the TFE would result in a higher ion-exchange capacity.
According to Appellant’s Specification, it was possible to obtain a
polymer having sufficient ion-exchange capacity with a higher content of
monomer of formula (1) by “improving the polymerization conditions”
(Spec. 4, ll. 12-19).
ANALYSIS
Appellant’s position is “there was no known practical method for
obtaining a polymer” as claimed (Reply. Br. 2); e.g., “because yields are too
low” in prior art methods (App. Br. 6). Appellant also contends that the only
disclosure in Krespan describing hydrolyzing such a polymer is with regards
to copolymers having a maximum of 10 mole percent of the
polyfluoroallyloxy comonomer (App. Br. 5). These arguments are not
persuasive of reversible error in the Examiner’s rejection.
The claim at issue is not a method claim, it is a product claim.
Krespan describes copolymers with up to 25 mole percent of the
polyfluoroallyloxy monomer (col. 11, ll. 35-37). One of ordinary skill in the
art would have known that increasing the mole percentage of hydrolyzed
monomer of Krespan (that corresponds to the claimed formula (1)) in the
resultant polymer with TFE would have resulted in a higher ion exchange
capacity (see, FF). Krespan describes such polymers with up to 25 mole
percent of (unhydrolyzed) polyfluoroallyloxy, even though Krespan only
explicitly discusses using up to 10 mole percent of polyfluoroallyloxy in
polymers which are subsequently hydrolyzed and used in a fuel cell (see,
FF).
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Appeal 2009-003568
Application 10/640,022

Accordingly, we agree with the Examiner that the use of Krespan’s
copolymer with a greater mole percent of the monomer of formula (1)
therein in order to obtain the predictable result of a higher ion-exchange
capacity as taught to be desirable in Uchida would have been within the
level of ordinary skill in the art, since it would have been the predictable use
of a known prior art element for its intended function. See, KSR, 550 U.S. at
417.
As aptly pointed out by Examiner, the “different methods and cost for
making the material [as argued by Appellant] are not material” to the present
product claims (Ans. 8). The combined teachings of Uchida and Krespan
would have led one of ordinary skill in the art, through no more than
ordinary creativity, to optimize the amount of the monomer of formula (1) in
order to obtain the ion-exchange capacity taught to be desirable in Uchida.
See KSR, 550 U.S. at 418 (a “court can take account of the inferences and
creative steps that a person of ordinary skill in the art would employ”).
Appellant has provided no evidence or convincing reasoning to refute
the Examiner’s reasonable inference that the copolymers of Krespan may
have been formulated with more of the monomer of formula (1) (which
contains the hydrolyzed -SO3H groups) therein so as to result in the claimed
ion exchange capacity taught to be desirable in Uchida.
Appellant’s arguments regarding their method do not negate the
Examiner’s conclusion that it would have been prima facie obvious to use
the claimed material for a polymer electrolyte fuel cell with an ion exchange
capacity as claimed based on the combined teachings of Uchida and
Krespan.
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Appeal 2009-003568
Application 10/640,022

Therefore, for the reasons above as well as those set out in the
Answer, we agree with the Examiner’s findings in support of obviousness
for claim 1 based on Uchida and Krespan.
CONCLUSION
Appellant has not shown that the Examiner reversibly erred in
rejecting the product claims because they allege that there was no known
practical method for obtaining an ion exchange capacity of 1.0 meq/g dry
resin for the claimed polymer.
It follows that we sustain the § 103 rejection of claims 1, 8, 10, and 11
as being unpatentable over the combined teachings of Uchida and Krespan.
ORDER
The Primary Examiner’s decision is affirmed.

No time period for taking any subsequent action in connection with
this appeal maybe extended under 37 C.F.R. § 1.136(a)(1)(v).

AFFIRMED

tc
OBLON, SPIVAK, MCCLELLAND, MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA, VA 22314
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