Ex Parte Kaneshiro et al

Patent Trial and Appeal Board

Jul 8, 2014

11674620 (P.T.A.B. Jul. 8, 2014)

UNITED STATES PATENT AND TRADEMARK OFFICE
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BEFORE THE PATENT TRIAL AND APPEAL BOARD

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Ex parte HISAYASU KANESHIRO, TOSHIHISA ITOH,
KATSUNORI YABUTA, and KIYOKAZU AKAHORI

Appeal 2012-011972
Application 11/674,620
Technology Center 1700
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Before BEVERLY A. FRANKLIN, KAREN M. HASTINGS, and
N. WHITNEY WILSON, Administrative Patent Judges.

WILSON, Administrative Patent Judge.

DECISION ON APPEAL
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Application 11/674,620

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STATEMENT OF THE CASE
Appellants1 appeal under 35 U.S.C. § 134 from the decision rejecting
claims 18, 20, 21, and 23. We have jurisdiction over the appeal under
35 U.S.C. § 6(b).
We reverse.

CLAIMED SUBJECT MATTER
Appellants’ invention is directed to a process for producing a
polyimide film (Spec. 1). Claim 18 is representative of the claims on appeal,
and is reproduced below from the Claims Appendix to the Brief (key claim
elements in italics):

18. A process for producing a polyimide film, comprising the
steps of:

casting and/or coating and subsequently drying an organic
solvent solution of polyamic acid on a support, so as to produce a
gel film, which is a partially cured and/or partially dried polyamic
acid film; and

imidizing the gel film to obtain the polyimide film,

said process producing the gel film by anyone of processes (1)
and (2):

(1) heating a polyamic acid composition on the support at
temperatures of at least two levels so as to obtain a gel film with
percent imidization of 50%, or greater;

detaching the gel film from the support; and

1 The Real Party-In-Interest is Kaneka Corporation (Br. 3).
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subsequently imidizing remaining polyamic acid and drying the
gel film by heating the gel film with its end portions fastened;

wherein in a last step of heating the polyamic acid composition
on the support at temperatures of at least two levels, the polyamic
acid composition is heated at a temperature range of 140° to 180°C;

(2) detaching a polyamic acid composition on the support with a
remaining volatile component, so that the gel film contains not less
than 50 parts by weight of an imidizing catalyst and not more than
30 parts by weight of a solvent, and not more than 20 parts by
weight of a dehydrating agent, with respect to 100 parts by weight of
the remaining volatile component, subsequently imidizing remaining
polyamic acid and drying the gel film by heating the gel film with its
end portions fastened.

REJECTIONS
Two rejections are appealed: (1) claims 18, 20, and 23 under
35 U.S.C. § 103(a) as being unpatentable over Nishida2 in view of Nagata3
(see, Ans. 4); and (2) claim 21 under 35 U.S.C. § 103(a) as being
unpatentable over Nishida in view of Nagata, and further in view of Sado4
(see, Ans. 8).
The Examiner finds that Nishida teaches each of the elements of claim
18 (see, Ans. 5-7), except that the Examiner also finds that Nishida does not
teach the last step of heating the polyamic acid composition on the support at
temperatures of at least two levels, in which the polyamic acid composition
is heated at a temperature range of 140° to 180°C (Ans. 5). To make out a

2 Nishida et al, JP 2000-191806, published July 11, 2000.
3 Nagata et al., EP 0 418 889 A2, published March 27, 1991.
4 Sado et al., U.S. Patent No. 4,788,098, issued November 29, 1988.
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Application 11/674,620

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prima facie case of obviousness, the Examiner relies on Nagata, finding that
Nagata teaches the preparation of a polyimide film, wherein the polyamic
acid gel is heated on the support at two temperature levels, with the last
heating step being conducted at a temperature of 150°-500°C (Ans. 7, citing
Nagata, p. 8, l. 25). In response to Appellants’ argument that the portion of
Nagata cited by the Examiner does not teach or suggest performing heating
the supported polyamic acid composition at temperatures of at least two
levels (Appeal Br. 16-17), the Examiner further finds that Nagata’s
disclosure of “heating at 30 to 80C with following treatment at 150-500C
represents [a] two-step procedure” (Ans. 13).

DISCUSSION
As noted above, each of Rejections (1) and (2) relies on the
Examiner’s finding that Nagata teaches a preparation of a polyimide film,
where the polyamic acid gel is heated on the support at two temperature
levels, and the last heating step is conducted at a temperature of 150°-500°C.
Appellants argue that the section of Nagata relied on by the Examiner in
support of this finding “merely discloses that when the polyamic acid is in a
gel state, the gel is heated at 30 to 80°C for 0.5 to 10 hours, and when the
polyamic acid is in a deswollen state, heating is conducted at 150 to 500°C
for 10 seconds to 10 hours” and that “[t]his portion does not disclose that the
heating is conducted in a stepwise manner at two temperature levels”
(Reply Br. 3).
Appellants’ argument is persuasive. Nagata does not state that the
heating occurs at two temperature levels. Instead, Nagata states that when
the polyamic acid is in a gel state – i.e., when it contains an organic solvent
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(Nagata, p. 4, ll. 14-16) - the gel is heated a temperature of from 30°-80°C
(Nagata, p. 8, ll. 25-27), which is well below the claimed value of
140°-180°. Nagata also states that when the polyamic acid is in a
“deswollen state” (without the organic solvent), heating occurs at a
temperature of 150°-500°C (Nagata, p. 8, ll. 27-29). A preponderance of the
evidence supports Appellants’ position that the Examiner has not shown that
Nagata teaches or suggests heating at temperatures of at least two levels,
wherein in a last heating step the polyamic acid composition is heated at a
temperature range of 140° to 180°C as required by process (1) of claim 1.5
To reject a claim in a patent application as obvious under
35 U.S.C. § 103(a), the Examiner must show a prima facie case of
obviousness, which includes a showing that each of the claimed limitations
are either shown or suggested by the prior art. In the absence of a proper
prima facie case of obviousness, an applicant who complies with the other
statutory requirements is entitled to a patent. In re Oetiker, 977 F.2d 1443,
1445 (Fed. Cir. 1992). In this instance, the Examiner has not provided
persuasive evidence that Nagata, or either of the other cited references,
discloses the claimed two-temperature level heating step within the claimed
temperature ranges. Accordingly, we reverse the obviousness rejections.

5 While claim 18 sets out options (1) and (2) for producing the gel film, the
Examiner does not address option (2) of claim 18.
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CONCLUSION
We REVERSE the rejection of claims 18, 20, and 23 under
35 U.S.C. § 103(a) as being unpatentable over Nishida in view of Nagata.
We REVERSE the rejection of claim 21 under 35 U.S.C. § 103(a) as
being unpatentable over Nishida in view of Nagata, and further in view of
Sado.
REVERSED

cdc