Ex Parte 6746639 et al

Patent Trial and Appeal Board

Nov 20, 2014

95001709 (P.T.A.B. Nov. 20, 2014)

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.
95/001,709 08/15/2011 6746639 111219RX 1238
38834 7590 11/20/2014
WESTERMAN, HATTORI, DANIELS & ADRIAN, LLP
1250 CONNECTICUT AVENUE, NW
SUITE 700
WASHINGTON, DC 20036
EXAMINER
JOHNSON, JERRY D
ART UNIT PAPER NUMBER
3991
MAIL DATE DELIVERY MODE
11/20/2014 PAPER
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.
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

SKC Kolon PI, Inc.
Requester

v.

Kaneka Corporation
Patent Owner and Appellant
____________

Appeal 2014-003384
Reexamination Control 95/001,709
Patent 6,746,639 B2
Technology Center 3900
____________

Before RICHARD M. LEBOVITZ, JEFFREY N. FREDMAN, and
JEFFREY B. ROBERTSON, Administrative Patent Judges.

ROBERTSON, Administrative Patent Judge.

DECISION ON APPEAL
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Patent Owner Kaneka Corporation (“Patent Owner”) appeals under
35 U.S.C. §§ 134(b) and 315(a) (pre-AIA) the Examiner’s decision to reject
claims 1-9.1 Third-Party Requester SKC Kolon PI, Inc. (hereinafter
“Requester”) urges that the Examiner’s decision must be affirmed.2 We
have jurisdiction under 35 U.S.C. §§ 134(b) and 315(a) (pre-AIA). We
affirm the Examiner’s decision to reject claims 1-9.

STATEMENT OF THE CASE
United States Patent 6,746,639 B2 (hereinafter the “’639 Patent”),
which is the subject of the current inter partes reexamination, issued to
Katsunori Yabuta and Kiyokazu Akahori on June 8, 2004. We have been
informed that the ’639 Patent is the subject of an infringement action styled
Kaneka Corporation v. SKC KOLON PI, INC, et al. (C.D. CAL. April 21,
2011) (No.2: 11cv03397), which is pending. (PO App. Br. 2.) We are

1 See Patent Owner’s Appeal Brief 2 (filed October 7, 2013) (hereinafter
“PO App. Br.”) Examiner’s Answer (mailed December 17, 2013)
(hereinafter “Ans.”); Right of Appeal Notice (mailed July 5, 2013)
(hereinafter “RAN.”). Regarding Patent Owner’s objection to the
Examiner’s Answer for incorporating the RAN by reference (PO Reb. Br.
12-13), such is not an appealable issue, but should have been challenged by
way of a timely filed petition. See 37 C.F.R. § 1.181.
2 See Requester’s Respondent Brief (filed November 7, 2013) (hereinafter
“Req. Resp. Br.”). Because Patent Owner did not timely file a complete
response to the Action Closing Prosecution (see Petition Decisions of
August 1, 2012, May 29, 2013, and July 2, 2014), Requester was not entitled
to file the response to the Action Closing Prosecution on August 29, 2012.
See 37 C.F.R. § 1.951(b). Accordingly, we have not considered those
portions of Requester’s Respondent Brief to the extent that it incorporates
evidence and arguments from that response.
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informed by Requester that the ’639 Patent is the subject of an ITC
proceeding styled In the Matter of Certain Polyimide Films, Products
Containing Same, and Related Methods - Inv. No. 337-TA-772. (Req. Resp.
Br. 1; Related Proceeding App’x.)
We heard oral argument on July 16, 2014, a transcript of which was
entered into the electronic record on August 7, 2014.
The ’639 Patent relates to a process for preparing polyimide film.
Claim 1, which is illustrative of the appealed subject matter, reads as
follows:
1. A process for preparing a polyimide film by extruding
and casting a composition of a resin solution containing a
poly(amic acid) varnish, comprising:
preparing the poly(amic acid) varnish having low
viscosity by polymerizing a tetracarboxylic dianhydride
component with a diamine component in a molar ratio of 1:1.01
to 1:1.05 or 1:0.95 to 1:0.99
preparing the composition of the resin solution by adding
to the poly(amic acid) varnish a dehydrating agent in an amount
of at least one mole and a chemically-imidizing catalyst in an
amount of at least 0.5 mole per 1 mole of amic acid of the
poly(amic acid) varnish.
(PO App. Br. 31 Claims App’x.)

Patent Owner contests the Examiner’s decision to reject the claims as
follows:
I. Claims 7 and 9 as not enabled under 35 U.S.C.
§ 112, first paragraph;
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II. Claims 1-3, 5 and 6 under 35 U.S.C. §102(b) as
anticipated by Sutton;3
III. Claims 4, 7, and 8 under 35 U.S.C. § 103(a) as
obvious over Sutton;
IV. Claims 1-8 under 35 U.S.C. § 103(a) as obvious
over Tetsuya4 considered with Okahashi;5
V. Claim 9 under 35 U.S.C. § 103(a) as obvious over
Tetsuya and Okahashi further in view of EP ’643;6
VI. Claims 1-8 under 35 U.S.C. § 103(a) as obvious
over Tetsuya considered with Hiroaki;7
VII. Claim 9 under 35 U.S.C. § 103(a) as obvious over
Tetsuya and Hiroaki further in view of EP ’643;
VIII. Claims 1-8 under 35 U.S.C. § 103(a) as obvious
over Tetsuya considered with Masamichi;8 and
IX. Claim 9 under 35 U.S.C. § 103(a) as obvious over
Tetsuya and Masamichi further in view of EP ’643.9

3 U.S. Patent No. 4,358,581 to Sutton, Jr. issued November 9, 1982.
4 Japanese Unexamined Publication No. 11-198157, July 27, 1999, citations
to English translation of record.
5 U.S. Patent No. 5,460,890 to Masakazu Okahashi et al. issued on October
24, 1995.
6 EP 0 189 643 B1 published on August 6, 1986.
7 Japanese Unexamined Patent Publication No. 2000-191781, July 11, 2000.
8 Japanese Unexamined Patent Publication No. 59-071827, April 23, 1984.
9 Although this rejection is not listed in the issues to be reviewed on appeal,
Patent Owner presents substantive arguments on this rejection. (PO App.
Br. 5, 29-30.)
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Enablement
Claims 7 and 9 stand rejected under 35 U.S.C. § 112, first paragraph.
Claims 7 depends from claim 1 and further recites that “the viscosity of the
poly(amic acid) varnish being at least 100 poise at 20º C.” Claim 9 depends
from claim 1 and recites that the “polyimide film has a tensile strength of at
least 225 MPa.”
The Examiner’s position is that although the ’639 Patent is enabling
for a viscosity of at most 2,000 poise at 20º C, it does not provide
enablement for the open-ended range for viscosity recited in claim 7. (RAN
3-4; see ’639 Patent, col. 3, ll. 40-41, col. 7, ll. 9-24.) For claim 9, the
Examiner’s position is that the ’639 Patent provides enablement for a tensile
film strength of up to 310 MPa in the machine direction, but it does not
provide enablement for the open-ended range recited in claim 9. (RAN 3-4;
see ’639 Patent, col. 11, ll. 1-6.)
Regarding claim 7, Patent Owner acknowledges that no upper limit is
recited for the viscosity, but argues that if the claim is given its broadest
reasonable interpretation in view of the specification, claim 7 is enabled.
(PO App. Br. 6.) Specifically, Patent Owner argues that because the ’639
Patent discusses disadvantages to the resulting film at higher viscosity in
terms of uneven film thickness and the presence of bubbles in the film,
combined with Comparative Example 4 showing that numerous bubbles are
present in the film at a viscosity at 20º C of 4,000 poise, one of ordinary skill
in the art would have interpreted claim 7 to have an upper viscosity limit of
4,000 poise. (PO App. Br. 6.) Patent Owner argues that the ’639 Patent
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provides detailed guidance on the entire scope of the claim, including a
description that when the viscosity is more than 2,000 poise, there is a
tendency for uneven thickness as well as the inclusion of bubbles into the
resin film. (PO App. Br. 7-8, citing ’639 Patent col. 7, ll. 15-19.) Patent
Owner contends also that claim 7 is dependent from claim 1, which was not
rejected for lacking enablement. (PO App. Br. 7.)
Regarding claim 9 which recites “a tensile strength of at least 225
MPa.,” Patent Owner contends that the recited tensile strength is supported
by the working examples and excerpts from the specification disclosing that
by extruding, casting, and film forming the claimed composition of a resin
solution, a polyimide film may be obtained, which does not have lowered
mechanical properties. (PO App. Br. 8.) Patent Owner argues that the
tensile strength is limited by the composition itself and that the specification
provides direction to obtain the recited tensile strength in terms of the
problems associated with the prior art, and the solution to maintain the
mechanical strength of the resin composition. (PO App. Br. 9.) Patent
Owner states that in view of the working examples and comparative
examples, there is no quantity of experimentation needed to obtain the
polyimide film without lowering mechanical strength. (PO App. Br. 9.)
Requester argues that Patent Owner is improperly trying to read an
upper limit to the viscosity into claim 7, because claim 7 does not recite
preventing bubbles in the film or improving thickness uniformity. (Req.
Resp. Br. 3.) Regarding claim 9, Requester contends that the ’639 Patent
recites examples with a tensile strength up to 310 MPa, such that one of
ordinary skill in the art could not have prepared films having tensile
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strengths included in the full scope of claim 9 without undue
experimentation. (Req. Resp. Br. 4.)
Accordingly, the dispositive issues with respect to enablement are:
Did the Examiner err in determining that claim 7 is not enabling for
the full range of viscosities recited therein?
Did the Examiner err in determining that claim 9 is not enabling for
the full range of tensile strength recited therein?

PRINCIPLES OF LAW
“To satisfy the enablement requirement of § 112, ¶ 1, a patent
application must adequately disclose the claimed invention so as to enable a
person skilled in the art to practice the invention at the time the application
was filed without undue experimentation.” In re Swartz, 232 F.3d 862, 863
(Fed. Cir. 2000) (citation omitted).
The scope of the claims must not be broader than the scope of the
enabling description in the specification. See Nat’l Recovery Tech., Inc. v.
Magnetic Separation Systems, Inc., 166 F.3d 1190, 1196 (Fed. Cir. 1999).
“The scope of enablement, in turn, is that which is disclosed in the
specification plus the scope of what would be known to one of ordinary skill
in the art without undue experimentation.” Id. (citation omitted).
To determine whether the necessary experimentation is undue, we
look at factors including “(1) the quantity of experimentation necessary, (2)
the amount of direction or guidance presented, (3) the presence or absence of
working examples, (4) the nature of the invention, (5) the state of the prior
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art, (6) the relative skill of those in the art, (7) the predictability or
unpredictability of the art, and (8) the breadth of the claims.” In re Wands,
858 F.2d 731, 737 (Fed. Cir. 1988).

ANALYSIS
Claim 7
As an initial matter, we note that claim 7 was newly added during the
reexamination proceeding and, as a result, is subject to review for
compliance under 35 U.S.C. § 112. Regarding Patent Owner’s position that
because claim 7 depends from claim 1 and there is no enablement rejection
of claim 1, claim 7 must also be enabled, we emphasize that originally
issued claims are not subject to reexamination for compliance under 35
U.S.C. § 112. (See 35 U.S.C. § 311(a), pre-America Invents Act.) (“Any
third-party requester at any time, may file a request for inter partes
reexamination by the Office of a patent on the basis of any prior art cited
under the provisions of section 301.”)
With respect to claim 7, we agree with Patent Owner that the viscosity
range of “at least 100 poise at 20ºC” is enabled by the ’639 Patent. That is,
claim 1, from which claim 7 depends, recites a “poly(amic acid) varnish
having low viscosity.” The ’639 Patent provides guidance that when the
viscosity of the poly(amic acid) varnish is high, for example, more than
2,000 poise, there is a tendency that the film thickness in the machine
direction becomes uneven and the resulting resin film can easily include
bubbles, the bubbles in the film being an indicator of a poly(amic acid)
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varnish having high viscosity. (Col. 7, ll. 15-19; col. 4, ll. 35-44; col. 3, ll.
16-20 and 24-31.)
In light of the recitation in claim 1 that the viscosity of the poly(amic
acid) must be “low,” combined with the guidance provided in the ’639
Patent with respect to acceptable viscosities, we disagree with the Examiner
that the open-ended range in claim 7 is not enabled. (RAN 3-4.) The
viscosity range in claim 7 is in fact not open-ended, but is limited by the
requirement in claim 1 that the viscosity of the poly(amic acid) be low. The
’639 Patent informs one of ordinary skill in the art as to how to control the
viscosity of the poly(amic acid) varnish and that when the viscosity of the
poly(amic acid) solution is high, the resulting polyimide film is
unacceptable. (’639 Patent, col. 4, ll. 30-41; col. 7, ll. 9-29.)
Requester argues that claim 7 encompasses poly(amic acid) varnishes
with viscosities beyond 2,000 poise in view of the recitation of claim 2 that
the viscosity is “at most 2,000 poise.” (Req. Resp. Br. 3-4.) However, the
’639 Patent discloses Comparative Example 4, where when a poly(amic
acid) varnish with a viscosity of 4,000 poise is used, “numerous bubbles
were observed” in the resulting film. (’639 Patent, col. 13, ll. 19-22.)
Therefore, the limit as to when the viscosity of the poly(amic acid) varnish
no longer may be characterized as “low” appears to be between 2,000 poise
and 4,000 poise at 20 ºC.10

10 There is insufficient evidence of record to support Patent Owner’s
contention that claim 7 should be interpreted to include poly(amic acid)
varnishes with viscosities of up to 4,000 poise because Comparative
Example 4 indicates that bubbles are formed in the resulting polyimide film
when a poly(amic acid) varnish with a viscosity of 4,000 poise is used. (PO
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In view of the guidance provided in the ’639 Patent, we have not been
directed to sufficient evidence that it would require undue experimentation
to determine where, in the range between 2,000 poise and 4,000 poise, the
viscosity of the poly(amic acid) would no longer be “low” as evidenced by
bubble formation in the resulting polyimide film. As stated above, the
patent describes how to control viscosity and routinely observe whether
viscosity is too high as evidenced by film unevenness and bubble formation.
Accordingly, we reverse the Examiner’s rejection of claim 7.

Claim 9
Regarding claim 9, although Patent Owner relies on the disclosure in
the ’639 Patent and the tensile strengths recited in Examples 1-3, we agree
with the Examiner that the open-ended range for the tensile strength recited
in claim 9 is not enabled by the ’639 Patent.
We acknowledge that Patent Owner points to the working examples
for support that the specification provides detailed direction on how to
maintain the mechanical strength of the composition, and in particular that
Comparative Examples 1-4 report tensile strengths of 185 MPa to 255 MPa,
while Examples 1-3 report values of 225 MPa to 310 MPa. (PO App. Br. 9.)
However, claim 9 is open-ended as to the tensile strength, requiring “a
tensile strength of at least 225 MPa.” Patent Owner did not rebut the

App. Br. 6; ’639 Patent, col. 12, l. 60 –col. 13, l. 27.) At most, Comparative
Example 4 discloses that the poly(amic acid) varnish used is of high
viscosity due to the bubbles present in the film produced. Comparative
Example 4 does not indicate that a viscosity of 4,000 poise is a limit of a
“poly(amic acid) varnish having low viscosity.”
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Examiner’s position that it would require undue experimentation to make
films with tensile strengths in excess of those made in the ’639 Patent.
Patent Owner argues that the tensile strength is limited by the composition,
itself, but did not provide guidance on how films with tensile strengths far
above 225 MPa would be made. The fact that the highest tensile strength
described in the patent is 310 Mpa (Appeal Br. 9) raises doubt that tensile
strengths outside this value could be made, particular values in the hundreds
and thousands which are encompassed by the unlimited range of claim 9.
In addition, the ’639 Patent provides only a general discussion on
maintaining mechanical properties, the adverse effect of dilution of the
poly(amic acid) varnish, and the effect of the dehydrating agent on the
tensile strength of the resulting film. (’639 Patent, col. 4, ll. 22-27, 48-51;
col. 8, ll. 8-20.) The ’639 Patent thus discusses ways of maintaining
mechanical properties such as tensile strength but is completely silent on
preparing films with tensile strengths above 310 MPa. Therefore, contrary
to Patent Owner’s view, the ’639 Patent does not provide sufficient detailed
direction to produce polyimide films with the tensile strengths of the open-
ended range recited in claim 9 without undue experimentation. As a result,
we affirm the Examiner’s rejection of claim 9 as not enabled for the full
scope of the claim.

Prior Art Rejections
Anticipation- Sutton
Patent Owner contends that the preamble of claim 1, which requires
extruding and casting, is limiting and Sutton fails to teach both extruding
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and casting.11 (PO App. Br. 10-12.) Patent Owner argues that Sutton fails
to disclose extrusion of a poly(amic acid) solution where the polymerization
is complete, which according to Patent Owner, is required in claim 1. (PO
App. Br. 12-13.) Patent Owner contends further that Sutton fails to disclose
the molar ratio of tetracarboxylic anhydride component with diamine
component recited in claim 1, because Sutton discloses the preparation of a
prepolymer and addition of more monomer as a finishing component, such
that the poly(amic acid) varnish as claimed is never formed. (PO App. Br.
13.)
Requester contends that the preamble does not limit the scope of the
claim because neither the specification nor the prosecution history suggests
that the alleged effects of the disclosed method are exclusive to extruding
and casting. (Req. Resp. Br. 7.) Requester argues that “extruding and
casting” recited in the preamble is not essential to understand and give
meaning to the claim terms or to provide antecedent basis to claim terms.
(Id. at 7-8.) Requester argues further that Sutton discloses extruding or
casting to emphasize that the resin solution disclosed therein need not be
extruded but may be cast directly onto a substrate. (Req. Resp. Br. 8.)
Requester contends that contrary to Patent Owner’s arguments, claim 1 does
not specify the degree of polymerization of the poly(amic acid) varnish and,
thus, does not require complete polymerization. (Req. Resp. Br. 9.)
Requester argues also that claim 1 does not preclude the addition of a
finishing component and that, even if the amount of the finishing component

11 Patent Owner also argues unexpected results. (PO App. Br. 11.)
However, we observe that the Sutton rejection before us is based on
anticipation, and as a result, unexpected results are not relevant.
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is taken into consideration, the ratio of dianhydride to diamine would still be
satisfied. (Req. Resp. Br. 11.)
Thus, the dispositive issues for this rejection are:
Is the preamble of claim 1 is entitled to patentable weight?
Does Sutton reasonably disclose extruding and casting as recited in
claim 1?
Does Sutton’s prepolymer satisfies the limitation of claim 1 of a
poly(amic acid) varnish?
ANALYSIS
Claim Interpretation
“‘During reexamination, as with original examination, the PTO must
give claims their broadest reasonable construction consistent with the
specification.’” In re Suitco Surface, Inc., 603 F.3d 1255, 1259 (Fed. Cir.
2010) (quoting In re ICON Health and Fitness, Inc., 496 F.3d 1374, 1379
(Fed. Cir. 2007)). Nevertheless, the Federal Circuit has repeatedly
“instructed that any such construction [must] be ‘consistent with the
specification, . . . and that claim language should be read in light of the
specification as it would be interpreted by one of ordinary skill in the art.’”
Id. at 1260. If a claim preamble, when read in the context of the entire
claim, recites limitations of the claim, or if the claim preamble is “necessary
to give life, meaning, and vitality” to the claim, then the claim preamble
should be construed as if in the balance of the claim. Pitney Bowes, Inc. v.
Hewlett-Packard Co., 182 F.3d 1298, 1305 (Fed. Cir. 1999) (citation
omitted).
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We begin by interpreting claim 1 and, specifically, whether the
preamble, which recites “[a] process for preparing a polyimide film by
extruding and casting a composition of a resin solution containing a
poly(amic acid) varnish” should be given patentable weight. We conclude
that the preamble is entitled to patentable weight.
The body of claim 1 recites “preparing the poly(amic acid) varnish” as
well as “preparing the composition of the resin solution” (emphasis added).
Thus, the body of the claim expressly relies on the preamble in order to
provide antecedent basis for the claims terms. As such, the preamble is
necessary to breathe life and meaning into the claims. In this regard, the
preamble recites a process for preparing a polyimide film by extruding and
casting a composition containing a poly(amic acid) varnish. Although the
body of the claim does not further recite the extruding and casting steps, we
will not dissect the preamble to accord weight to one portion of the preamble
while at the same time disregarding another portion as is apparently
advocated by Requester. (Req. Resp. Br. 6.) Thus, we agree with the Patent
Owner that the preamble is entitled to some patentable weight. (See PO
Reb. Br. 3-4.)

Sutton-Anticipation
Having construed claim 1 as requiring extruding and casting, we turn
to the question of whether Sutton discloses this step in producing a
polyimide film. We agree with Requester that “casting” is the step of
depositing the resin solution on a substrate after it exits the extrusion die.
(Req. Resp. Br. 8, citing ’639 Patent, col. 7, l. 51; col. 10, ll. 31-32.) The
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’639 Patent states that the invention “relates to a process for preparing a
polyimide film by a casting process with a T-die in extrusion.” (Col. 1, ll. 6-
7.) The ’639 Patent describes extruding a composition of a resin solution
from a T-die and casting it on a stainless endless belt. (Col. 10, ll. 31-32;
see also Figs. 1 and 2.) Thus, the casting step in the process of extruding
and casting is the depositing step after the resin solution exits the extrusion
die.
Sutton discloses the industrial manufacture of shaped polyimide
articles in accordance with the patent “permits casting or extruding” the
composition. (Col. 8, ll. 45-58.) Sutton also discloses making a film which
is cast into a plate. (Col. 6, l. 9 and 36; col. 7, ll. 37-39). Sutton also
discloses that the polymer can be formed into any shape. (Col. 5, ll. 29-30.)
Based on these teachings, one of ordinary skill in the art would have
understood that Sutton teaches that its films can be cast on plates, after
extrusion, to form a film, meeting the “extruding and casting” limitation of
claim 1.12 Indeed, at oral argument, Patent Owner acknowledged that the

12 In the “Background Art” section, Sutton references two patents, U.S.
Patent No. 3,410,826 (issued to Andrew L. Endrey on November 12, 1968)
and U.S. Patent No. 3,541,057 (Issued to John Anthony Kreuz on November
17, 1970), for the production of polyimide. (Col. 1, ll. 31-35, 48-54.) Each
of these patents discloses: “Films of the [polyamide-acid] solution can be
conveniently formed by extruding the solution through an orifice onto a belt,
drum or similar smooth surface.” (’826 Patent, col. 6, ll. 46-49; ’057 Patent,
col. 4, ll. 6-9.) This disclosure is consistent with the ’639 Patent’s
description of the extruding and casting step. Thus, one of ordinary skill in
the art would immediately envisage that when a polyimide film is formed
via extrusion in accordance with the description in Sutton, there also would
be a casting step.
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combination of extruding and casting in the preparation of polyimide films
was conventional. (Or. Hr. Tr. 13, ll. 17-23; 15, ll. 6-15.)
In addition, we are not persuaded by Patent Owner’s argument that
Sutton fails to disclose the molar ratio of tetracarboxylic dianhydride to
diamine component of 1:1.01 to 1:1.05 or 1:0.95 to 1:0.99 as recited in the
claims. Patent Owner’s argument is based on the position that Sutton’s
“prepolymer” is not a poly(amic acid) varnish as recited in claim 1, because
Sutton discloses adding a “finishing component” including additional
monomer subsequent to the preparation of the prepolymer, in addition to the
subsequent addition of a dehydrating agent and imidization catalyst to adjust
the amounts of diamine or dianhydride monomer. (PO App. Br. 13.)
Initially, we note that claim 1 recites the transitional phrase
“comprising,” which renders the claim open to other steps or components
not expressly recited in the claim, such as the addition of more monomer in
the form of dianhydride or diamine. In this regard, we are not persuaded by
Patent Owner’s argument that the term “poly(amic acid) varnish” recited in
claim 1 imparts any particular degree of polymerization to the composition
that would exclude Sutton’s prepolymer from meeting all the limitations of
the claim. Although Patent Owner contends that Sutton discloses an
oligomer, which is distinguishable from the poly(amic acid) varnish recited
in claim 1, we have not been directed to sufficient evidence of record to
support Patent Owner’s position.
Sutton discloses generally a preferred ratio of acid dianhydride to
diamine of 1.01 to 1.50 and a preferred ratio of 1.02 to 1.20, both of which
overlap the ratio recited in claim 1. (Sutton, col. 3, ll. 12-15.) Sutton
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discloses, in Example 2, a prepolymer having a ratio of dianhydride to
diamine of 1.04:1, which falls squarely within the range recited in claim 1.
(Sutton, col. 6, ll. 20-26.) The prepolymer produced is dissolved in
dimethylacetamide to produce a solution. Id. Thus, Sutton discloses a
poly(amic acid) varnish as recited in claim 1. Moreover, as pointed out by
Requester, the addition of the finishing component in Sutton does not bring
the ratio of dianhydride to diamine outside the ratio recited in claim 1. (Req.
Resp. Br. 11.) Accordingly, we agree with the Examiner that Sutton
anticipates claim 1. Patent Owner does not argue separately the limitations
of claims 2, 3, 5, and 6. Therefore, claims 2, 3, 5, and 6 fall with claim 1.

Obviousness Rejections
Obviousness-Claims 4, 7, and 8 over Sutton
Patent Owner does not set forth separate arguments for patentability
of claims 4, 7, and 8, which depend from claim 1, as offered for claim 1.
(PO App. Br. 14.) Accordingly, we affirm the Examiner’s rejection of
claims 4, 7, and 8 for the same reasons as discussed above with respect to
claim 1.

Tetsuya combined with Okahashi
As pointed out by Patent Owner, the Examiner acknowledges that
Tetsuya does not require a composition of a resin solution that contains at
least one mole dehydrating agent and at least 0.5 moles of imidizing catalyst
per mole of amic acid of the polyamide acid solution. (PO App. Br. 14;
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RAN 8.) The Examiner relies on Okahashi to supply the recited ratios of
dehydrating agent and imidizing catalyst. (RAN 8-9.)
Patent Owner argues that the claimed molar ratios of diamine to
tetracarboxylic anhydride, amounts of dehydrating agent, and amounts of
catalyst provide results that would have been unexpected over the teachings
of the prior art and are critical to achieving certain advantages of a
polyimide film produced by the claimed process. (PO App. Br. 15-18.)
Patent Owner argues that Okahashi does not teach or suggest the specified
claimed molar ratios and amounts recited in the claims, because Okahashi is
focused on improved dimensional stability and in-plane isotropy. (PO App.
Br. 18.) Patent Owner contends that Okahashi does not disclose or
recognize the importance of the molar ratio and amounts in producing films
having the advantages provided by the claims and, thus, fails to recognize
the criticality associated with the limitations of claim 1. (PO App. Br. 18-
19.)
Regarding claim 9, which is rejected over the combination of Tetsuya
and Okahashi, further in view of EP ’643, Patent Owner argues that the
tensile strength values reported in EP ’643 are not indicative of the tensile
strength values associated with polyimide films produced by the methods of
Tetsuya or Okahashi. (PO App. Br. 19.) Patent Owner argues that the
Examiner did not provide a specific analysis as to how films with the tensile
strengths recited in the claims could be produced using the extruding and
casting of Tetsuya or Okahashi, when the ’639 Patent discloses that
preparation of the films using extruding and casting lead to reduced tensile
strength as compared to those produced by conventional methods, which
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conventional methods Patent Owner alleges are disclosed in EP ’643. (PO
App. Br. 19.)
Requester contends that Patent Owner does not contest the prima facie
case of obviousness set forth by the Examiner, because, even though Patent
Owner points out the Okahashi does not disclose the ratios and amounts
recited in the claims, the Examiner relied on Tetsuya for that feature, and the
Patent Owner criticizes each reference individually, rather than the
combination set forth by the Examiner. (Req. Resp. Br. 14-15.) Regarding
Patent Owner’s arguments pertaining to unexpected results, Requester
contends that the data relied on by Patent Owner fails to compare the
claimed subject matter with the closest prior art, does not support Patent
Owner’s contentions of unexpected results, and also does not overcome the
strong case of obviousness. (Req. Resp. Br. 15-19.)
With respect to claim 9, Requester argues that Patent Owner’s
position is supported only by attorney argument and EP ’643 is good for all
it teaches regarding tensile strength. (Req. Resp. Br. 19.) Requester
contends that Patent Owner’s argument is flawed because it demands more
of EP ’643 then is recited in Patent Owner’s specification as to how to
achieve the claimed tensile strength. (Req. Resp. Br. 20.)
Thus, the dispositive issues for this rejection are:
Did the Examiner err in finding that Okahashi disclosed the ratios of
dianhydride to diamine recited in claim 1?
Did the Examiner err in determining that the evidence of unexpected
results was insufficient to outweigh the evidence in favor of obviousness?
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Did the Examiner err in concluding that the tensile strength recited in
claim 9 would have been obvious in view of Tetsuya, Okahashi, and EP
’643?

ANALYSIS
Claims 1-8
Patent Owner does not appear to contest the rationale provided by the
Examiner for combining Tetsuya and Okahashi. (PO App. Br. 14-15.) To
the extent that Patent Owner argues that Okahashi does not disclose the
molar ratios of tetracarboxylic anhydride to diamine recited in the claims
(PO App. Br. 18), we note that the Examiner did not rely on Okahashi for
those disclosures, but instead relied on Tetsuya. To the extent that Patent
Owner argues that Okahashi does not disclose the amounts of dehydrating
agent and chemically-imidization catalyst recited in the claims (PO App. Br.
18), we disagree. Okahashi discloses a concentration of cyclization catalyst
of 0.5-8 moles per 1 mole of polyamic acid and a concentration of
dehydrating agent of 0.1 to 4 moles per 1 mole of polyamic acid, which
significantly overlap with the amounts recited in claim 1. (Col. 4, ll. 16-25.)
As a result, Patent Owner’s contention is not persuasive.

Unexpected Results
The majority of Patent Owner’s argument centers around unexpected
results of the ratios recited in the claims. We are not persuaded by Patent
Owner’s arguments that the data presented in the ’639 Patent is sufficient to
support the position that the claimed process produces unexpected results
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over the teachings of the prior art. Specifically, the statements in the ’639
Patent that poly(amic acid) varnishes with an equimolar ratio of dianhydride
to diamine are highly viscous and result in films with the inclusion of
bubbles and uneven thickness, and that dilution of such varnishes result in
reduced mechanical properties are not sufficient evidence of unexpected
results. (PO App. Br. 15.) Similarly, the statements that, when the molar
ratio of dianhydride to diamine, the amount of dehydrating agent, or the
amount of catalyst is outside the recited ranges, there is a decrease in
mechanical properties are not sufficient to prove unexpected results. (PO
App. Br. 15-16.) We explain our rationale in more detail below.
With respect to the effect of the ratio of dianhydride to diamine on
viscosity, Tetsuya discloses a mixing ratio of dianhydride to diamine of
1:1.005 to 1:1.05, which significantly overlaps with the range recited in
claim 1, and states that when such ratio is lower than 1:1.005 (closer to
equimolar), the viscosity of the polyamide acid solution increases. (Tetsuya,
Para. [0034].) In addition, Tetsuya recognizes that, if the viscosity of the
polyamide acid composition is higher than desired, the resulting film is non-
uniform in thickness and foam entrainment readily occurs. (Tetsuya, Para.
[0038].)
Patent Owner contends also that when the molar ratio of diamine
component is more than 1.05, the degree of polymerization of poly(amic
acid) varnish obtained therefrom is low and as a result leads to a marked
reduction in the mechanical properties including reduction in mechanical
strength by more than 90% relative to films prepared by conventional
methods. We do not find Patent Owner’s argument persuasive, because
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Tetsuya teaches the same upper limit of the diamine as set forth in the claim.
Thus, the concept that viscosity of the polyamide acid solution impacts
uniformity of film thickness as well as bubble entrainment of the resulting
polyimide film, and the concept of controlling the ratio of dianhydride to
diamine to ratios significantly overlapping the ratio range in claim 1 was
known in the art and, therefore, was not surprising or unexpected.
Regarding the amount of dehydrating agent, as pointed out by
Requester, all of the comparative examples contain an amount of
dehydrating agent that are within the claimed ranges. (Req. Resp. Br. 16.)
The ’639 Patent, in describing the range of amounts of dehydrating agent
and the effect on mechanical properties, does not provide any statement that
the range of amounts recited in the claims would have been unexpected or
surprising. (’639 Patent, col. 7, ll. 45-47, col. 8, ll. 1-20.) As a result, we
are not persuaded by Patent Owner’s position.
Patent Owner also argues that when the amount of catalyst is outside
the recited ranges, there is a decrease in mechanical properties which is
unexpected. The Comparative Examples of the ’639 Patent contain amounts
of catalyst that are well below the low end of the recited range in claim 1 at
0.27 (Comp Exs. 1, 2, and 4) and 0.26 (Comp. Ex. 3). In particular,
Comparative Example 4 produces a tensile strength of 255 MPa, which is
the same tensile strength obtained in Examples 1 and 2 that purport to be
according to the invention. Thus, the examples do not provide sufficient
proof of unexpected results since catalyst values outside the range produce
acceptable mechanical properties. Further in this regard, although Patent
Owner appears to contend that Comparative Example 1 of the ’639 Patent is
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comparable to Example 1 of Tetsuya (PO Reb. Br. 9), Comparative Example
1 contains variables that all fall within the claimed ranges with the exception
of the amount of catalyst, which as discussed above is not sufficient to show
unexpected results.

Claim 9
We are unpersuaded by Patent Owner’s arguments that one of
ordinary skill in the art would not have combined EP ’643 with Tetsuya and
Okahashi to produce a polyimide film having a tensile strength of at least
225 MPa. EP ’643 discloses polyimide films having a tensile strength at
least about 20 kg/mm2 and especially 25 kg/mm2. (EP ’643, p. 5, ll. 5-10.)
It is undisputed that the tensile strength disclosed in EP ’643 meets the
tensile strength recited in claim 9. Patent Owner argues that because EP
’643 produces polyimide films by casting on copper foil, drying, solidifying,
and heat treating, which according to Patent Owner is a “conventional
method,” and the ’639 Patent discloses that the tensile strength is reduced by
more than 90% using extruding and casting from polyimide films produced
by conventional methods, the Examiner did not provide sufficient evidence
that a film having the tensile strength recited in claim 9 could be produced
using the methods of Tetsuya or Okahashi. (PO App. Br. 19.)
We disagree. Specifically, as discussed above, Tetsuya discloses
similar molar ratios of dianhydride to diamine as are disclosed in the ’639
Patent in order to maintain the mechanical properties of the polyimide film.
(’639 Patent, col. 3, ll. 15-34.) In addition, Okahashi discloses amounts of
catalyst and dehydrating agent as claimed, also argued to affect the
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mechanical properties. (Col. 4, ll. 15-25.) Thus, there is no indication that
one of ordinary skill in the art would not have been able to obtain a
polyimide film having the tensile strength recited in claim 9.
We acknowledge that the ’639 Patent states that lowering the
polymerization degree as disclosed in Tetsuya reduces the mechanical
properties of the film compared to a polyimide film prepared from equimolar
diamine component and tetracarboxylic dianhydride component. (’639
Patent col. 2, ll. 54-60.) However, the ’639 Patent discloses that the
viscosity of the poly(amic acid) varnish is adjusted by controlling the
polymerization degree of an acid dianhydride component and diamine
components, which is relatively low, where the viscosity range is at most
2,000 poise and most preferably 100 to 1,500 poise at 20ºC. (’639 Patent,
Col. 7, ll. 9-15, 25-29.) In addition, Tetsuya discloses that the viscosity of
the resin composition is preferably adjusted to 450 poise or less, which
significantly overlaps the range disclosed in the ’639 Patent. (Tetsuya para.
[0023].) Thus, the ’639 Patent and Tetsuya disclose significantly
overlapping ratios of dianhydride component and diamine component as
well as significant overlapping ranges in viscosity. Accordingly, Patent
Owner did not meet the burden of establishing that one of ordinary skill in
the art would have found tensile strengths of the magnitude disclosed in EP
’643 unobvious over the method disclosed by the combination of Tetsuya
and Okanashi.

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Obviousness over Tetsuya in combination with either Hiroaki or
Masamichi
The Examiner relies on Hiroaki and Masamichi to supply the recited
ratios of dehydrating agent and imidizing catalyst similar to the combination
of Tetsuya and Okahashi discussed above. (RAN 10-11, 13-14.) Patent
Owner’s arguments with respect to the rejections over Tetsuya in
combination with either Hiroaki or Masamichi are similar to the arguments
addressed above with respect to Tetsuya in combination with Okahashi. (PO
App. Br. 20-30.)
Regarding Hiroaki, Patent Owner argues additionally that the
Examiner has failed to explain why one of ordinary skill in the art would
have considered Hiroaki, which is directed to a method of manufacturing a
liquid crystal orienting film, to be relevant in forming a polyimide film
because the method of Hiroaki does not involve extruding and casting. (PO
App. Br. 20.) We are not persuaded by Patent Owner’s arguments. Both
Tetsuya and Hiroaki are directed to the preparation of polyimide films.
(Tetsuya para. [0006]; Hiroaki, paras. [0029] – [0031].) Because Tetsuya is
silent on a general discussion of what amounts of catalyst and dehydrating
agent are suitable for preparing polyimide films, we agree that one of
ordinary skill in the art would have turned to Hiroaki for guidance as to the
range of amounts of each of the catalyst and dehydrating agent to be applied
in Tetsuya’s method of forming polyimides. (Req. Resp. Br. 20-21.) Patent
Owner has provided insufficient evidence to support the position that one of
ordinary skill in the art would not have considered Hiroaki to be relevant to
the polyimide film formation disclosed in Tetsuya.
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Patent Owner’s remaining arguments regarding unexpected results are
not persuasive for similar reasons as discussed with respect to the rejection
of Tetsuya in view of Okahashi.

DECISION
The Examiner’s decision to reject claims 1-9 is affirmed.
In accordance with 37 C.F.R. § 41.79(a)(1), the “[p]arties to the
appeal may file a request for rehearing of the decision within one month of
the date of . . . [t]he original decision of the Board under § 41.77(a).” A
request for rehearing must be in compliance with 37 C.F.R. § 41.79(b).
Comments in opposition to the request and additional requests for rehearing
must be in accordance with 37 C.F.R. § 41.79(c)-(d), respectively. Under
37 C.F.R. § 41.79(e), the times for requesting rehearing under paragraph (a)
of this section, for requesting further rehearing under paragraph (d) of this
section, and for submitting comments under paragraph (c) of this section
may not be extended.
An appeal to the United States Court of Appeals for the Federal
Circuit under 35 U.S.C. §§ 141-144 and 315 and 37 C.F.R. § 1.983 for an
inter partes reexamination proceeding “commenced” on or after November
2, 2002 may not be taken “until all parties’ rights to request rehearing have
been exhausted, at which time the decision of the Board is final and
appealable by any party to the appeal to the Board.” 37 C.F.R. § 41.81. See
also MPEP § 2682 (8th ed., Rev. 7, July 2008).

AFFIRMED

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peb

PATENT OWNER:
WESTERMAN, HATTORI, DANIELS & ADRIAN, LLP
1250 Connecticut Avenue, NW
Suite 700
Washington, DC 20036

THIRD-PARTY REQUESTER:
FINNEGAN, HENDERSON, FARABOW, GARRETT & DUNNER LL
901 New York Avenue, N.W.
Washington, DC 20001-4413