Ex Parte Gawryla et al

Patent Trial and Appeal Board

May 9, 2018

13377574 (P.T.A.B. May. 9, 2018)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
13/377,574 12/12/2011
23908 7590 05/11/2018
RENNER OTTO BOISSELLE & SKLAR, LLP
1621 EUCLID AVENUE
NINETEENTH FLOOR
CLEVELAND, OH 44115
FIRST NAMED INVENTOR
Matthew D. Gawryla
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
ATTORNEY DOCKET NO. CONFIRMATION NO.
AEROPOl 02WOUS 5285
EXAMINER
ZEMEL, IRINA SOPJIA
ART UNIT PAPER NUMBER
1765
NOTIFICATION DATE DELIVERY MODE
05/11/2018 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@rennerotto.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte MATTHEW D. GA WRYLA and DAVID A. SCHIRALDI
Appeal2016-005274
Application 13/377,574
Technology Center 1700
Before MARK NAGUMO, JAMES C. HOUSEL, and
N. WHITNEY WILSON, Administrative Patent Judges.
HOUSEL, Administrative Patent Judge.
DECISION ON APPEAL 1
Pursuant to 35 U.S.C. § 134(a), Appellants2 appeal from the
Examiner's decision rejecting claims 1-5 and 7-16. We have jurisdiction
over the appeal under 35 U.S.C. § 6(b).
We AFFIRM.
1 Our decision refers to the Specification (Spec.) filed December 12, 2011,
the Examiner's Non-Final Office Action (Non-Final) dated April 22, 2014,
Appellants' Appeal Brief (Appeal Br.) filed October 19, 2015, the
Examiner's Answer (Ans.) dated February 16, 2016, and Appellants' Reply
Brief (Reply Br.) filed April 18, 2016.
2 According to Appellants, the real party in interest is Case W estem Reserve
University. Appeal Br. 2.
Appeal2016-005274
Application 13/377,574
STATEMENT OF THE CASE
The invention relates to a method for preparing aerogels by subjecting
an aerogel precursor to a freeze/thaw cycle prior to freeze drying (Spec. 1,
Technical Field). According to Appellants, subjecting the aerogel precursor
to a freeze/thaw cycle prior to freeze drying improves the compressive
strength of the resulting aerogel (id. at 4:3-10).
Appellants disclose that highly porous aerogels and aerogel-like
structures include a three-dimensional, open-cell body formed using two-
phase systems, including dispersions, emulsions, solutions, suspensions, and
latexes (id. at 4:27-30). The aerogel may be polymer based, and may be
formed solely from one or more polymers in combination with a dispersion
medium, or clays, additives, fillers, fibers, etc. may be combined with the
polymer and dispersion to form the aerogel (id. at 4:20-26). Appellants
further disclose that "[t]he polymer used in the aerogel may be one or more
monomers, polymers, copolymers, or combinations thereof' (Spec. 5:8-9).
For the dispersion medium, Appellants disclose "any suitable liquid
compound or mixture of compounds that forms a crystalline phase structure
when frozen and is sublimable" may be used, and may be a solvent that
dissolves the polymer (id. at 8:8-15).
Sole independent claim 1, reproduced below from the Claims
Appendix to the Appeal Brief, is illustrative of the subject matter on appeal.
The limitation at issue is italicized.
1. A method of forming an aero gel, including:
forming an aerogel precursor, the aerogel precursor
including a matrix material and a liquid dispersion medium for
dispersing the matrix material, wherein the matrix material
includes a polymeric material, the polymeric material present in
the aerogel precursor from about 1 wt% to about 5 wt%;
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performing at least two freeze/thaw cycles on the aerogel
precursor, each freeze/thaw cycle including:
freezing the aerogel precursor so that the
dispersion is solidified; and
thawing the aerogel precursor to liquefy the frozen
dispersion medium;
freezing the aerogel precursor after performing the at
least two freeze/thaw cycles so that the dispersion is solidified;
and
freeze drying the aerogel precursor to sublime the
dispersion medium and form the aerogel.
REJECTIONS
The Examiner maintains, and Appellants request our review of, the
following grounds of rejection under 35 U.S.C. § 103(a):
1. Claims 1-5 and 7-14 as unpatentable over Schiraldi 3 in view of
any one of Stauffer, 4 Peppas, 5 and Urushizaki; 6
2. Claim 15 as unpatentable over Schiraldi and any one of
Stauffer, Peppas, and Urushizaki, further in view of Loeb; 7 and
3. Claim 16 as unpatentable over Schiraldi and any one of
Stauffer, Peppas, and Urushizaki, further in view of Woerpel. 8
3 US 2008/0132632 Al, published June 5, 2008 ("Schiraldi").
4 Shauna R. Stauffer and Nikolaos A. Peppas, Poly(vinyl alcohol) Hydrogels
Prepared by Freeze-Thawing Cyclic Processing, 33 POLYMER, No. 18,
3932-3936 (1992) ("Stauffer").
5 Nikolaos A. Peppas and Jill E. Scott, Controlled Release From Poly(vinyl
alcohol) Gels Prepared by Freeze-Thawing Processes, 18 J. CONTROLLED
RELEASE 95-100 (1992) ("Peppas").
6 Fumio Urushizaki, et al., Swelling and Mechanical Properties of Poly(vinyl
alcohol) Hydrogels, 58 INT'L J. PHARMACEUTICS 135-142 (1990)
("Urushizaki").
7 US 4,059,970, issued November 29, 1977 ("Loeb").
8 US 4,200,228, issued April 29, 1980 ("Woerpel").
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Application 13/377,574
ANALYSIS
Appellants argue neither the claims nor the rejections separately,
instead focusing solely on the rejection of claim 1. Accordingly, we limit
our review of Appellants' arguments to claim 1. Remaining claims 2-5 and
7-16 stand or fall therewith. 37 C.F.R. § 41.37(c)(l)(iv) (2015).
After review of the opposing positions articulated by Appellants and
the Examiner and the evidence of obviousness adduced by the Examiner in
light of the countervailing Declaration evidence proffered by Appellants, we
determine that the Appellants' arguments and evidence are insufficient to
outweigh the evidence of obviousness marshalled by the Examiner. Thus,
Appellants have not identified reversible error in the Examiner's
obviousness rejection of claim 1. In re Jung, 637 F.3d 1356, 1365 (Fed. Cir.
2011 ). Accordingly, we affirm the stated obviousness rejections for
substantially the fact findings and the reasons set forth by the Examiner in
record before us. We offer the following for emphasis only.
The following facts are not in dispute (compare Non-Final 2-3 with
Appeal Br. 6-7; see also Ans. 3):
Schiraldi discloses a method for forming an aerogel from a precursor
including poly( vinyl alcohol) ("PVOH") as recited in claim 1 except for the
at least two freeze/thaw cycles.
Stauffer, Peppas, and Urushizaki each disclose preparing hydrogels
from a precursor including PVOH in an aqueous dispersion medium using a
plurality of freeze/thaw cycles, wherein the resulting hydro gels have
improved mechanical strength. Stauffer's precursor includes 10-15 wt%
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PVOH, whereas Peppas' and Urushizaki's precursor each includes 15 wt%
PVOH.
Based on these facts, the Examiner concludes that it would have been
obvious to modify Schiraldi' s method for forming an aero gel to include
several freeze/thaw cycles to obtain gels with improved properties as taught
by Stauffer, Peppas, and Urushizaki (Non-Final 3).
Appellants argue that the Declaration under 37 C.F.R. § 1.132 of Dr.
David A. Schiraldi ("Schiraldi Declaration" or "Dec.") filed February 13,
2015 establishes that there was no reason to expect that freeze/thaw cycling
an aerogel precursor, particularly at "relatively low polymer concentrations
(i.e., 1 wt% to 5 wt%)" would have provided any advantage (Appeal Br. 4).
In this regard, Appellants contend the Schiraldi Declaration states that it was
expected that thawing a frozen aerogel precursor would result in the loss of
any structure formed by the polymer and/or clays, fillers, and additives
during freezing (id.; see also id. at 9). According to Appellants, this
expectation is consistent with the thermodynamic law of entropy, "which
requires that a system return to its most randomized state in the absence of
applied forces" (id.). Therefore, Appellants contend that freeze/thawing of
an aerogel precursor "was conventionally viewed as a meaningless exercise"
(id.). In light of the conventional view, Appellants urge that they
unexpectedly found that freeze-thaw cycling the aerogel
precursor allows for the number of domains of crystals in which
the layers are oriented in the same direction to increase while
also decreasing in their respective sizes. It was quite surprising
that the aerogel precursor, despite the relatively low polymer
concentration, maintained a localized structural memory when
subjected to freeze-thaw cycling (which in-tum lead to the
increased number of the domains).
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Id. at 5. In addition, Appellants assert that aerogels formed using
freeze/thaw cycling have improved compressive strength over
aero gels formed without such freeze/thaw cycling (id.).
Appellants further argue that each of Stauffer, Peppas, and Urushizaki
describes the formation of a hydrogel, not an aerogel (Appeal Br. 7).
Appellants characterize a hydrogel as a colloidal gel in which water is
dispersed and retained in a polymer network (matrix), whereas an aerogel is
a solid, highly porous, and low density material (id.; see also Reply Br. 2-3).
Appellants assert that the polymer concentration of a hydrogel precursor is
typically high, e.g., above 10 wt%, as compared with the polymer
concentration in an aerogel precursor, e.g., about 1 wt% to about 5 wt% as
recited in claim 1 (id.). Appellants urge that they fail to see how the
teachings of the secondary references using higher polymer concentrations
could be extrapolated to any precursor polymer concentration (id. at 11; see
also Reply Br. 5---6). Appellants contend, therefore, that there would have
been no rational basis to modify Schiraldi' s aero gel production method in
view of the hydro gel production processes of Stauffer, Peppas, and
Urushizaki (id. at 8).
These arguments are not persuasive of reversible error in the appealed
rejection of claim 1. The Examiner's rejection merely extends the teaching
of the secondary references beyond the PVOH concentration range taught
therein, but within the range taught in Schiraldi. In re Sernaker, 702 F .2d
989, 994 (Fed. Cir. 1983) (motivation to combine may be based on "whether
a combination of the teaching of all or any of the references would have
suggested (expressly or by implication) the possibility of achieving further
improvement by combining such teachings along the line of the invention in
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suit"). Moreover, "[i]t is well established that a determination of
obviousness based on teachings from multiple references does not require an
actual, physical substitution of elements." In re Mouttet, 686 F.3d 1322,
1332 (Fed. Cir. 2012) (citing In re Etter, 756 F.2d 852, 859 (Fed. Cir. 1985)
(en bane)); see also In re Keller, 642 F.2d 413, 425 (CCPA 1981) ("To
justify combining reference teachings in support of a rejection it is not
necessary that a device shown in one reference can be physically inserted
into the device shown in the other" (citation omitted)). "Rather, the test is
what the combined teachings of the references would have suggested to
those of ordinary skill in the art." Keller, 642 F.2d at 425 (citation omitted);
see also In re McLaughlin, 443 F.2d 1392, 1395 (CCPA 1971) ("the test for
combining references is not what the individual references themselves
suggest but rather what the combination of disclosures taken as a whole
would suggest to one of ordinary skill in the art.").
Initially, we note the Schiraldi Declaration states that the conventional
view was that freeze/thaw cycling would be a meaningless exercise because
it was thought that the precursor would return to its pre-frozen state upon
thawing, particularly at low polymer concentrations. However, Declarant
fails to explain satisfactorily why the teachings of Stauffer, Peppas, and
Urushizaki would have been expected to fail at about 5 wt% PVOH.
Although each of these references using a higher polymer concentration than
the range of claim 1, neither Declarant nor Appellants persuasively explain
via factual evidence why the phenomena observed by Stauffer, Peppas, and
Urushizaki, i.e., formation of a persistent PVOH cross-linked network or
matrix after successive freeze/thaw cycling using precursors at 10-15 wt%
PVOH, would not have been expected at lower concentrations such as 5
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wt% PVOH. Declarant states that, particularly in the case of relatively low
polymer concentrations, the ordinary artisan would have expected the
system to return to its original state when thawed after being frozen (Dec. 2).
Yet, Declarant does not provide a persuasive evidentiary basis or technical
reasoning in support of this statement at polymer concentrations only two to
three times less than the prior art references teaching hydro gels. Neither
Declarant nor Appellants direct our attention to any disclosure in any of the
secondary references indicating that the observed phenomena of the building
of a persistent polymer cross-linked network is limited to concentrations of
10-15 wt%. Indeed, we note Appellants disclose that the polymer
concentrations in the precursor for aerogels may be about 1 to about 40 wt%,
and that "[h ]igher concentrations of polymer in solution will generally
produce robust structures, but will reduce the porosity and provide for higher
densities" (Spec. 8:24--31 ). Appellants fail to persuade us that the ordinary
artisan would not have reasonably expected freeze/thaw cycling lower
polymer concentration precursors to similarly benefit from the phenomena
observed by the secondary references.
With regard to Appellants' attempt to contrast hydro gels from
aerogels, we note that the only differences between the methods of
producing the hydro gels of Stauffer, Peppas, and Urushizaki and the method
of forming the aero gel of claim 1 are the different concentrations and the
final freeze drying step. Urushizaki, in particular, reports that with each
successive freeze/thaw cycle, more of the polymer is incorporated into the
network (Urishizaki 137, col. 2, second para.). The fact that the network
builds with each cycle indicates that a force is at work, which Urushizaki
identifies as cross-linking of the polymer. That the degree of cross-linking
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increases indicates that the strength of inter-chain bonding is sufficient to
survive the dilution that occurs in subsequent freeze-thawing cycles.
Therefore, we are not persuaded that the ordinary artisan would have
reasonably inferred that the persistent polymer network formed by
successive freeze/thaw cycling observed by each of Stauffer, Peppas, and
Urushizaki would not occur in the slightly more dilute precursor used to
form an aerogel, i.e., freeze drying Schiraldi's PVOH precursor following
the plural freeze-thaw cycles recommended by the secondary references.
In addition, Appellants argue that the stability for a hydrogel is
different than the stability associated with that of an aero gel (Appeal Br. 10).
Appellants assert that stability in Schiraldi refers to that of the freeze dried
aerogel, whereas the stability discussed in Stauffer, Peppas, and Urushizaki
refers to the hydro gel obtained at the higher polymer concentration (id.).
Appellants contend "[i]t is improper to summarily equate the different
contexts in which stability is present in the references, particularly in view of
the different polymer concentrations and different processes for producing
the hydrogel and aerogel" (id. at 10-11).
We note here that Appellants' claim 1 does not recite any properties
for the resulting aerogel, much less stability. Appellants also fail to direct
our attention to any evidence or persuasive technical reasoning that the
stability of the resulting aero gel is an unexpected property. Notwithstanding
the lack of such a showing, we note that although hydrogels and aero gels are
distinct final products, the phenomena observed by the secondary references
would have been reasonably expected, as discussed above, in Schiraldi' s
precursor upon successive freeze/thaw cycles. As such, the ordinary artisan
would likewise have reasonably expected that the resulting persistent, cross-
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linked polymer network would not only provide improved mechanical
strength as recognized by the secondary references, but also would
contribute greater stability in both the hydrogel and the freeze dried aerogel.
Finally, we note that though Declarant and Appellants present data on
the modulus (kPa) of aerogels at 2.5 and 5.0 wt% PVOH with and without
freeze/thaw cycling (Dec. 3; Spec. 16), Appellants do not argue that this data
would have been interpreted as evidence of an unexpected result. In re
Mayne, 104 F.3d 1339, 1344 (Fed. Cir. 1997) ("Even were it obvious to a
practitioner of the art, applicants have the burden to provide the PTO with
evidence showing that such is the case."). Nevertheless, on this record, a
preponderance of the evidence supports the determination, as discussed
above, that the ordinary artisan would have reasonably expected, applying
the teachings of the secondary teachings to the method of Schiraldi, that the
resulting aerogel would possess improved mechanical strength as taught in
the secondary references.
DECISION
Upon consideration of the record, and for the reasons given above and
in the Non-Final Office Action of April 22, 2014 and the Examiner's
Answer, the decision of the Examiner rejecting claims 1-5 and 7-23 under
35 U.S.C. § 103(a) as unpatentable over Schiraldi in view of any one of
Stauffer, Peppas, and Urushizaki, alone or further in view of Loeb or
W oerpel, is affirmed.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(l).
AFFIRMED
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