Ex Parte Hrubesh

Board of Patent Appeals and Interferences

Aug 10, 2007

10050437 (B.P.A.I. Aug. 10, 2007)

The opinion in support of the decision being entered today
is not binding precedent of the Board.

UNITED STATES PATENT AND TRADEMARK OFFICE
____________________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________________

Ex parte LAWRENCE W. HRUBESH
____________________

Appeal No. 2007-1938
Application No. 10/050,4371
Technology Center 1700
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Decided: August 10, 2007
____________________

Before RICHARD TORCZON, CAROL A. SPIEGEL and
MARK NAGUMO, Administrative Patent Judges.

SPIEGEL, Administrative Patent Judge.

DECISION ON APPEAL

I. Introduction
Lawrence W. Hrubesh (hereinafter "Appellant") seeks our review
under 35 U.S.C. § 134 of the Examiner's final rejection of claims 1, 4, 8 and

1 The application on appeal was filed 15 January 2002. The real parties-in-
interest are said to be the Regents of the University of California and the
United States of America as represented by the United States Department of
Energy.
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18, all of the claims pending in this application. We have jurisdiction under
35 U.S.C. § 6(b). We AFFIRM.
The claimed subject matter relates to a method for producing a carbon
aerogel composite. Claim 1 is illustrative of the subject matter on appeal:
1. A method comprising:
infiltrating a solution containing a plurality
of carbon aerogel precursors into a pre-formed
polymer foam, or fiber-mat,
allowing said solution to gel such that it
encapsulates at least part of the pre-formed
polymer foam or fiber-mat to form a gelled
composite,
drying the gelled composite to form a dried
composite such that the surface tensile forces are
reduced, and
pyrolyzing the dried composite wherein the
preformed polymer foam or fiber-mat and the
carbon aerogel decompose simultaneously such
that they remain essentially in contact at their
interfaces to form a monolithic glassy carbon
material.
The Examiner has relied on the following references of record as
evidence of unpatentability:
Kaschmitter US 5,260,855 Nov. 9, 1993
Pekala US 5,932,185 Aug. 3, 1999
Droege US 5,945,084 Aug. 31, 1999
The Examiner has rejected claims 1 and 18 under 35 U.S.C. § 102(b)
as anticipated by Droege; claims 4 and 8 under 35 U.S.C. § 103(a) as
obvious over Droege; and, claims 1, 4, 8 and 18 as under 35 U.S.C. § 103(a)
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as obvious over Pekala in view of Kaschmitter (Answer2 2). Kaschmitter,
Pekala and Droege qualify as prior art under 35 U.S.C. § 102(b).
Appellant relies on the following documents of record as evidence of
patentability:
Declaration under 37 CFR § 1.132 of Lawrence W. Hrubesh dated 19
January 2005 ("the Hrubesh Declaration")

Lu et al. ("Lu"), "Thermal and electrical conductivity of monolithic
carbon aerogels," J. Appl. Phys., vol. 73, no. 2, pp. 581-584 (15 January
1993)

Tajiri et al. ("Tajiri"), "Effects of supercritical drying media on
structure and properties of silica aerogel," J. Non-Crystalline Solids, Vol.
186, pp. 83-87 (1995).

Since Appellate has indicated that all the claims stand or fall together
(Br. at 4), we decide this appeal on the basis of claim 1. 37 CFR
§ 41.37(c)(1)(v).
II. Findings of Fact ("FF")
The following findings of fact are supported by a preponderance of
the evidence of record. To the extent any "finding of fact" is a conclusion of
law, it should be so treated.
A. Appellant's specification
[1] Aerogels are said to be fragile materials (Specification ¶ 3).
[2] A composite of an organic aerogel and a reticulated vitreous carbon
("RVC") is said to combine the optical, thermal, acoustic, and

2 We refer to the Supplemental Examiner's Answer ("Answer") mailed 16
November 2006 in response to the Corrected Brief on Appeal ("Br.") filed
23 October 2006.
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electrical properties of an aerogel with the strength of an RVC
(Specification ¶ 4).
[3] According to the specification, "[t]he structure of the final carbon
product of this invention consists of a matrix of porous carbon
aerogel, reinforced by solid carbon struts, all in intimate contact so
that the strength of the composite is maximized" (Specification ¶ 11).
[4] Further according to the specification, the composite is made by
infiltration of an organic gel precursor into a pre-
formed organic polymer foam, where it gels. The
gel composite is then dried by any method that
minimizes shrinkage of composite material.
Whereafter, the dried gel composite is heated in a
furnace to pyrolyze the composite, reducing it to a
glassy carbon form. [Specification ¶ 11.]
[5] The organic gel precursor may be an aqueous solution comprising
resorcinol, formaldehyde and sodium carbonate (Specification ¶ 14).
[6] The organic polymer foam may comprise a phenol-formaldehyde
resin (Specification ¶ 14).
[7] Gelling may occur at a 80oC for 30 to 180 minutes (Specification ¶
14).
[8] Drying may occur by evaporation for 12 to 48 hours or by
supercritical drying after fluid exchange with liquid carbon dioxide
(Specification ¶ 14)
[9] Pyrolyis may be at a temperature of 700 to 1100oC for 8 to 12 hours
(Specification ¶ 14).
[10] Pyrolysis is said to simultaneously decompose both the organic
polymers "so that the shrinkage of each occurs in a manner that
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essentially maintains contact of the polymers at their interface"
(Specification ¶¶ 13 and 16).
[11] The specification does not define the claim term "monolithic."
[12] Table 1 is said to show data for composites of carbon aerogel and (a)
phenolic resin foam, (b) resorcinol resin foam and (c) furan foam
(Specification 6:1).
[13] Table 1 does not show any porosity data for the three carbon aerosol-
foam composites which are said to have densities of (a) 125, (b) 124
and (c) 115 kg/m3, respectively (Specification 6, Table 1).
B. Droege
[14] Droege describes a method of forming an aerogel/carbon substrate
composite comprising infusing a porous carbon substrate with a
mixture of carbon aerogel precurors, allowing the infused porous
carbon substrate to form a gel/porous substrate composite, curing the
gel/porous substrate composite, drying the cured gel/carbon substrate
composite and pyrolyzing the dried gel/carbon substrate composite
(Droege col. 2, ll. 15-20; col. 7, ll. 18-20; col. 14, ll. 15-65).
[15] The carbon aerogel precursors comprise an aqueous solution of
resorcinol ("R"), formaldehyde and a sodium carbonate catalyst ("C")
having a molar concentration R/C value of greater than about 1000
(Droege col. 4, ll. 24-30; col. 5, ll. 1-5; col. 6, l. 65 - col. 7, l. 5; col.
14, ll. 25-31).
[16] The porous carbon substrate may take a variety of forms, including
fibers and reticulated foams (Droege col. 14, ll. 49-65).
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[17] Droege describes typical gelation temperatures from about 20 to about
70oC and typical gelation times from about 0.1 to about 24 hours
(Droege col. 9, ll. 50-51 and 56-57).
[18] Droege describes typical curing temperatures from about 50 to about
95oC and typical curing times from about 3 to about 72 hours (Droege
col. 10, ll. 17-18 and 23-24).
[19] Conventional drying methods, including supercritical evaporation
using carbon dioxide exchange, may be used (Droege col. 10, l. 65-
col. 11, l. 6 and col. 11, ll. 27-45).
[20] Droege describes typical pyrolysis temperatures from about 600 to
3000o C, e.g., from about 800 to about 1150o C, and typical pyrolysis
times from about 1 to about 6 hours (Droege col. 13, ll. 22-25 and 29-
30).
[21] According to Droege, pyrolysis temperature varies with pyrolysis time
and the composition and amount of aerogel (Droege col. 13, ll. 19-
22).
[22] According to Droege, its aerogels are characterized by meso-pore size
distributions including embodiments from about 5 to about 50 nm,
from about 7 to about 50 nm, from about 10 to about 50 nm, and from
about 10 to about 25 nm (Droege col. 11, ll. 54-65).
[23] For example, processing aerogels prepared with a solids content of
greater than R=50% w/v yield gels with pore sizes not larger than
about 100 nm (Droege col. 12, ll. 19-30).
[24] Example 3 of Droege is said to describe formation of an
aerogel/carbon fiber substrate composite having a pore size
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distribution of 20 nm and a density of 419 kg/m3 (Droege col. 16, l. 40
- col. 17, l. 7, esp. col. 17, ll. 3-4, and col. 19, l. 15).
[25] The Examiner found that Droege taught a method comprising (i)
forming a reaction mixture containing a plurality of carbon aerogel
precursors, e.g., resorcinol and formaldehyde, (ii) infiltrating a porous
carbon or organic substrate in the form of a foam, fiber, etc., with the
reaction mixture, (iii) heating at a gelation temperature to gel the
reaction mixture, (iv) heating the composite at a curing temperature to
cure the gel, (v) drying the composite and (vi) pyrolyzing the
composite to carbonize (Answer 2; Rejection3 3).
[26] The Examiner found that Droege taught drying by conventional
methods, including supercritical evaporation using supercritical
carbon dioxide (Answer 2; Rejection 3).
[27] The Examiner construed the claim term "monolithic" as meaning "a
uniform whole" (Answer 3).
[28] Thus, the Examiner found claims 1 and 18 anticipated by Droege
(Answer 2).
[29] The Examiner also found that gelation and pyrolysis times and
temperatures were result effective variables (Answer 2; Rejection 4).
[30] The Examiner concluded that it would have been obvious to one of
ordinary skill in the art to use a gelation temperature slightly higher
than the 20 to 70o C range taught by Droege, e.g., 80o C as recited in
claim 4, in order to allow for a shorter gelation time (Answer 2;
Rejection 4).

3 We refer to the Office action mailed 20 July 2004 ("Rejection") cited in the
Answer.
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[31] The Examiner further concluded that it would have been obvious to
one of ordinary skill in the art to use a pyrolysis time longer than the
typical 1 to 6 hours taught by Droege, e.g., 8 to 12 hours as recited in
claim 8, to ensure that pyrolysis and carbonization is fully achieved
(Answer 2; Rejection 4).
[32] Appellant argues that Droege fails to teach a drying step which
adequately reduces surface tensile forces to produce a monolithic
composite or how to form an essentially monolithic composite when
pyrolyzed (Br. 4).
[33] Appellant relies on the Hrubresh Declaration in support of his position
(Br. 4).
C. The Hrubesh Declaration
[34] Lawrence W. Hrubesh, Ph.D., is the named inventor of the application
on appeal (Hrubesh Declaration at 1-2).
[35] Dr. Hrubesh testified that "monolithic glassy carbon composites of the
present invention have average pore sizes that are less than 100 nm"
because monolithic aerogels of comparable densities have average
pore sizes less than 100 nm as confirmed by Lu (Hrubesh Declaration
at 2).
[36] Dr. Hrubesh further testified that "typical pore sizes for supercritically
dried aerogels are less than 10 nm" as shown by Tajiri (Hrubesh
Declaration at 2).
[37] The Examiner found that the Hrubesh Declaration is not
commensurate in scope with the claims because it appears to require
particular drying conditions, whereas the claims are not so limited "so
long as surface tensile forces are reduced" (Answer 3).
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D. Lu
[38] According to Lu, SiO2 aerogels with densities of about 150 kg/m3
have pore sizes < 100 nm (Lu 581, col. 1, ¶ 1).
E. Tajiri
[39] Tajiri discussed the effects of supercritical drying media on the
structure and properties of silica aerogels and "concluded that the
supercritical drying medium affects the aerogel structure" (Tajiri 86,
col. 2, ¶ 2).
[40] According to Tajiri, pore sizes less than 10 nm were obtained with
methanol and 2-propanol-dried aerogels (Tajiri 85, col. 2, ¶ 1).
[41] Table 1 of Tajiri lists specific critical temperature and pressure
parameters for methanol, ethanol, 2-propanol and carbon dioxide
drying medium (Tajiri 84).
Other findings of fact follow below.
III. Anticipation and Obviousness Rejections Based on Droege
Anticipation requires disclosure of each and every claim limitation in
a single prior art reference, either explicitly or inherently. MEHL/Biophile
Int'l Corp. v. Milgraum, 192 F.3d 1362, 1365, 52 USPQ2d 1303, 1305 (Fed.
Cir. 1999). It is well settled that "anticipation is the epitome of
obviousness." Cornell v. Sears Roebuck & Co., 722 F.2d 1542, 1548, 220
USPQ 193, 198 (Fed. Cir. 1983) (quoting In re Fracalossi, 681 F.2d 792,
794, 215 USPQ 569, 571 (CCPA 1982)).
The Examiner found that Droege teaches the same method of forming
an aerogel/carbon substrate composite as claimed by Appellant (Answer 2;
Rejection 3-4). The Examiner also found "[i]t is expected that any method
of drying will reduce the surface tensile forces to some degree" (Answer 3).
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Appellant argues, as to claim 1, that Droege "teaches a drying method
that does not reduce surface tensile forces adequately to produce a
monolithic composite" and "does not teach how to produce an essentially
monolithic foam/mat aerogel composite" (Br. 4). Appellant relies on the
definition of a monolithic composite provided by Dr. Hrubesh in his
Declaration (Br. 4). Dr. Hrubesh testified that his inventive monolithic
glassy carbon composites have average pore sizes less than 100 nm (FF 35).
Dr. Hrubesh based his opinion on typical pore sizes found in silica aerogels
of the prior art said to have "comparable densities" or prepared by
"supercritical drying" (FF 35 and FF 36). In essence, Appellant relies on an
"inverse" product-by-process argument which contends that the claimed
process produces a "monolithic" glassy carbon aerogel composite having an
average pore size less than 100 nm, whereas the Droege process does not.
First, Appellant's specification does not define the claim term
"monolithic" used to characterize the product produced by the claimed
method or provide any porosity data for the three carbon aerosol foam
composites discussed in its Table 1 (FF 11 and FF 13). The Examiner has
construed the claim term "monolithic" as meaning "a uniform whole" (FF
27). During examination of a patent application, claims are given their
broadest reasonable construction consistent with the specification. In re
Zletz, 893 F.2d 319, 320-21, 13 USPQ2d 1320, 1322 (Fed. Cir. 1989). “The
reason is simply that during patent prosecution when claims can be
amended, ambiguities should be recognized, scope and breadth of language
explored, and clarification imposed.” Id. “An essential purpose during
patent examination is to fashion claims that are precise, clear, correct, and
unambiguous.” Id. 893 F.2d at 322, 13 USPQ2d at 1322. “Only in this way
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can uncertainties of claim scope be removed, as much as possible, during the
administrative process.” Id. Appellant has not amended his claims to state
clearly and unambiguously that the recited method steps produce a carbon
aerogel composite having an average pore size of less than 100 nm. Nor has
Appellant pointed to any evidence of record establishing that one of ordinary
skill in the art would have understood a monolithic glassy carbon composite
prepared by any method within the scope recited in the claims would
necessarily have an average pore size of less than 100 nm.
Here, Droege describes the same method steps as recited in claim 1
and describes using the same materials and method steps as set forth in
Appellant's specification (FF 28). Droege describes aerogels having pore
sizes not larger than 100 nm (FF 23) and expressly exemplifies a carbon
aerogel fiber composite having a pore size distribution of 20 nm and a
density of 419 kg/m3 (FF 24). Furthermore, the density of the carbon
aerogel fiber composite of Droege Example 3 appears "comparable" to the
~ 150 kg/m3 density of the silicon aerogels disclosed by Lu (FF 38) and the
115-125 kg/m3 densities said to be attributed to the carbon aerogel foam
composites shown in Table 1 of Appellant's specification (FF 13).
Moreover, Appellant has not shown that the properties of a Droege carbon
aerogel composite are not comparable to the properties of a carbon aerogel
composite produced by the claimed method. Compare In re Thorpe, 777
F.2d 695, 697, 227 USPQ 964, 965-66 (Fed. Cir. 1985) (product-by-process
patent properly denied where end result was indistinguishable from prior
art). The Hrubesh Declaration does not provide measurements of the
average pore size of a carbon aerogel composite produced by the claimed
method or explained how the structure and properties of silica aerogels
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relate to carbon aerogels and carbon aerogel composites. Thus, the weight
of the evidence indicates that the Droege method produces a "monolithic
glassy carbon" material composite. Appellant has not shown otherwise.
Appellant's argument that Droege "teaches a drying method that does
not reduce surface tensile forces adequately to produce a monolithic
composite" is also unpersuasive of Examiner error. Appellant has not
explained what defines an "adequate" reduction in surface tensile forces,
e.g., reduced vis-à-vis what standard reduction. Without a reasoned basis for
comparing the drying step of claim 1 with the drying step of Droege, we find
that the method of Droege meets the drying limitation of the claimed
method. Moreover, since the method of Droege produces a monolithic
glassy carbon material, e.g., a monolithic carbon aerogel composite having a
pore size distribution less than 100 nm (FF 22-FF 24), it appears that
Droege's method does satisfy the claim limitation of a drying step "such that
the surface tensile forces are reduced." Appellant has not come forward
with evidence to the contrary.
Therefore, based on the foregoing, we will affirm the rejections of
claims 1 and 18 under § 102(b) and of claims 4 and 8 under § 103(a) over
Droege.
IV. Obviousness Rejection Based on Pekala in view of Kaschmitter
A claimed invention is not patentable if its subject matter would have
been obvious to a person of ordinary skill in the art. 35 U.S.C. § 103(a); KSR
Int'l Co. v. Teleflex, Inc., 127 S.Ct. 1727, 82 USPQ2d 1385 (2007); Graham
v. John Deere Co. of Kansas City, 383 U.S. 1 (1966). Facts relevant to a
determination of obviousness include (1) the scope and content of the prior
art, (2) any differences between the claimed invention and the prior art, (3)
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the level of ordinary skill in the art and (4) relevant objective evidence of
nonobviousness. KSR, 127 S.Ct. at 1734, 82 SUPQ2d at 1389; Graham, 383
U.S. at 17-18.
A. Pekala
[42] Pekala discloses a method for producing thin carbon aerogel foam
hybrid/composite electrodes comprising infiltrating a porous material,
e.g., carbon papers, with a carbon foam (i.e., aerogel) precursor
material which is subsequently cured and pyrolyzed at high
temperatures, i.e., 500-3000o C, to form composite (Pekala col. 1, ll.
11-19; col. 2, ll. 18-26).
[43] The carbon foam precursor material may include an aqueous
resorcinol, formaldehyde and sodium carbonate solution (Pekala col.
2, ll. 61-67; col. 3, l. 66 - col. 4, l. 3).
[44] Pekala describes drying using conventional techniques, e.g.,
supercritical drying using carbon dioxide (Pekala col. 4, ll. 21-23).
[45] Example 3 of Pekala is said to describe preparation of a carbon
aerogel foam composite electrode having a density of ~ 600 kg/m-3
(Pekala col. 4, ll. 12-13).
[46] According to the Examiner, Pekala does not teach the hydroxylated
benzene compound (e.g., resorcinol) to catalyst ratio required by the
precursor solutions (Answer 2; Rejection 6).
B. Kaschmitter
[47] According to Kashmitter, the highest capacitance for carbon aerogel
electrodes is said to be observed with an R/C value of 50 (Kashmitter
col. 3, ll. 5-63, esp. at ll. 58-59).
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[48] The Examiner concluded that it would have been obvious to one of
ordinary skill in the art to use the a carbon aerogel precursor solution
having an R/C value of 50 as disclosed by Kashmitter in the process
of Pekala in order to obtain the highest capacitance from the produced
electrode (Answer 2; Rejection 6).
[49] Appellant argues that the composites produced by Pekala and
Kashmitter do not form monolithic foam/mat aerogel composites
because the composites must have a relatively large average pore size
to enable fluid transport therethrough (Br. 5).
[50] Appellant again relies on the Hrubesh Declaration for support (Br. 4).
[51] Dr. Hrubesh testified that both Pekala and Kaschmitter require a pore
size large enough so that electrolyte fluid can flow through the
electrode (Hrubesh Declaration 3).
[52] Dr. Hrubesh concludes that the large pore size of the composites
produced by Pekala and Kaschmitter excludes the composites from
being "monolithic" composites.
C. Discussion
The Examiner finds that Pekala teaches a method corresponding to the
method of claims 1 and 18 and concluded that it would have been obvious to
adjust parameters such as curing or pyrolysis times and temperatures to meet
the limitations of dependent claims 4 and 8 (Answer 2; Rejection 5). The
Examiner also maintains that it would have been obvious to use certain
aerogel precursor reagent ratios as taught by Kaschmitter to obtain high
capacitance from the carbon composite electrodes (Answer 2; Rejection 6).
Appellant only argues that the pore size of the carbon composite
electrodes produced by the Pekala/Kaschmitter method must be larger than
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100 nm for the electrodes to work (Br. 4-5; Hrubesh Declaration 4). Since,
according to Appellant, monolithic foam/mat aerogel composites must have
pore sizes less 100 nm, the method of Pekala/Kaschmitter cannot teach or
suggest the claimed method (id.).
As discussed above, Appellant has failed to provide evidence
sufficient to establish a pore size of less than 100 nm as a proxy definition of
the "monolithic glassy carbon material" recited as the goal of the claimed
method. Analogous to the above discussion, Appellant has failed to provide
a sufficient basis from which to conclude that the Pekala/Kaschmitter
method would not have been reasonably expected to produce a monolithic
glassy carbon material given that Pekala/Kaschmitter teaches using the same
materials and method steps. Moreover, Pekala teaches a carbon aerogel
foam composite electrode having a density of ~ 600 kg/m-3 (FF 45) which
appear comparable to the ~ 150 kg/m3 density of the silicon aerogels
disclosed by Lu (FF 38). In short, Appellant has not submitted evidence and
arguments sufficient to rebut the prima facie case of obviousness set forth by
the Examiner.
Therefore, based on the foregoing, we will affirm the rejection of
claims 1, 4, 8 and 18 under § 103(a) as obvious over Pekala in view of
Kaschmitter.
CONCLUSION
In summary, the decision of the Examiner to reject (i) claims 1 and 18
under 35 U.S.C. § 102(b) as anticipated by Droege; (ii) claims 4 and 8 under
35 U.S.C. § 103(a) as obvious over Droege; and, (iii) claims 1, 4, 8 and 18
as under 35 U.S.C. § 103(a) as obvious over Pekala in view of Kaschmitter
is affirmed.
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No time period for taking any subsequent action in connection with
this appeal may be extended under 37 CFR § 1.136(a).
AFFIRMED

smt

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THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
LAWRENCE LIVERMORE NATIONAL LABORATORY
PO BOX 808, L-703
LIVERMORE CA 94551-0808