Ex Parte Witzke et al

Patent Trial and Appeal Board

Mar 26, 2013

11636742 (P.T.A.B. Mar. 26, 2013)

UNITED STATES PATENT AND TRADEMARKOFFICE
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.
11/636,742 12/11/2006 Tim Witzke SGL 05/32 8956
24131 7590 03/27/2013
LERNER GREENBERG STEMER LLP
P O BOX 2480
HOLLYWOOD, FL 33022-2480
EXAMINER
SNELTING, ERIN LYNN
ART UNIT PAPER NUMBER
1741
MAIL DATE DELIVERY MODE
03/27/2013 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
____________

Ex parte TIM WITZKE
and BODO BENITSCH
____________

Appeal 2011-009984
Application 11/636,742
Technology Center 1700
____________

Before CHARLES F. WARREN, TERRY J. OWENS, and
GEORGE C. BEST, Administrative Patent Judges.

BEST, Administrative Patent Judge.

DECISION ON APPEAL
On May 4, 2010, the Examiner finally rejected claims 1-20 of
Application 11/636,742 under 35 U.S.C. § 103(a) as obvious. Appellants
seek reversal of these rejections pursuant to 35 U.S.C. § 134(a). We have
jurisdiction under 35 U.S.C. § 6(b).
For the reasons set forth below, we AFFIRM.
Appeal 2011-009984
Application 11/636,742
2
BACKGROUND
The ’742 application describes a process for making a ceramic that
contains silicon carbide. Spec. 1. The method described in the ’742
application allegedly allows the production of high density silicon carbide
ceramics that may be used to construct components that are subject to high
levels of mechanical or thermal stress, or which are exposed to harsh
chemical environments. Id. at 5.
Claim 1 is representative of the ’742 application’s claims and is
reproduced below:
1. A process for producing ceramic containing silicon
carbide and having a geometric density of at least 2.80 g/cm3,
which comprises the steps of:
providing ground wood charcoal having particles with a particle
size of not more than 40 μm;
producing a homogeneous mixture formed from the ground
wood charcoal and a carbonizable binder;
producing a shaped body being a green body from the
homegeneous mixture;
carbonizing the green body to form a carbonized precursor
body at a temperature of at least 900°C in a nonoxidizing
atmosphere; and
silicizing the carbonized precursor body by infiltration with a
silicon melt.
(App. Br. Claims App’x 1).
Appeal 2011-009984
Application 11/636,742
3
REJECTIONS
1. The Examiner finally rejected claims 1, 4, 6, 8, 10-12, 15, and 16
under 35 U.S.C. § 103(a) as obvious over Brun1 in view of Gupta.2
2. The Examiner finally rejected claims 2, 3, 13, 14, and 20 under 35
U.S.C. § 103(a) as obvious over the combination of Brun and
Gupta in view of Kozar.3
3. The Examiner finally rejected claim 5 under 35 U.S.C. § 103(a) as
obvious over the combination of Brun and Gupta as evidenced by
Charcoal.4
4. The Examiner finally rejected claim 7 under 35 U.S.C. § 103(a) as
obvious over the combination of Brun, Gupta, and Kozar, in view
of Newman.5
5. The Examiner finally rejected claim 9 under 35 U.S.C. § 103(a) as
obvious over the combination of Brun, Gupta, Kozar, and Newman
in view of Sohda.6
6. The Examiner finally rejected claim 17 under 35 U.S.C. § 103(a)
as obvious over the combination of Brun and Gupta in view of
Newman.
7. The Examiner finally rejected claim 18 under 35 U.S.C. § 103(a)
as obvious over the combination of Brun and Gupta in view of
Sohda.

1 U.S. Patent No. 5,316,851 (issued May 31, 1994).
2 U.S. Patent No. 4,564,496 (issued Jan. 14, 1986).
3 U.S. Patent No. 3,616,045 (issued Oct. 26, 1971).
4 Charcoal, WIKIPEDIA (Dec. 3, 2005) (available at
http://web.archive.org/web/20051203154000/http://en.wikipdia.org/wiki/Ch
arcoal>). Appellants do not challenge this reference’s status as prior art.
5 U.S. Patent No. 3,957,957 (issued May 18, 1976).
6 U.S. Patent No. 5,057,254 (issued Oct. 15, 1991).
Appeal 2011-009984
Application 11/636,742
4
8. The Examiner finally rejected claim 19 under 35 U.S.C. § 103(a)
as obvious over the combination of Brun, Gupta, and Kozar in
view of Sohda.
DISCUSSION
Rejection 1. The Examiner finally rejected claims 1, 4, 6, 8, 10-12,
15, and 16 as obvious over the combination of Brun and Gupta (Ans. 4).
Appellants do not argue for the patentability of these claims individually.
We, therefore, select claim 1 as representative of the group. See 37 C.F.R.
§ 41.37(c)(1)(vii).
Appellants argue that Brun does not describe or suggest the claimed
invention because Brun does not describe or suggest making the preform
body from particles of wood charcoal having a particle size of less than 40
μm to produce a ceramic containing silicon carbide with a geometric density
of at least 2.80 g/cm3 (App. Br. 9-13). Appellants further argue that Gupta
does not remedy these defects (id. at 13-14). For the following reasons, we
are not persuaded by these arguments and affirm the Examiner’s rejection.
First, Brun expressly describes the use of charcoal powders that are
less than 50 μm, and preferably between 1 and 15 μm in size. Brun col. 5,
ll. 2-27. While Brun does not specifically state that the charcoal is derived
from wood, a person of ordinary skill in the art would understand that wood
is one of the sources of charcoal. See, e.g., “Charcoal,” Dictionary.com,
http://dictionary.reference.com/browse/charcoal?s=t&path=/ (accessed
March 21, 2013) (“the carbonaceous material obtained by heating wood or
other organic substances in the absence of air”). Thus, Brun, in and of itself,
suggests the use of wood charcoal powder that is less than 40 μm in size.
Appeal 2011-009984
Application 11/636,742
5
Second, although Brun suggests the use of wood charcoal powder in
the production of a silicon carbide ceramic, the Examiner also cited Gupta
for its description of the use of wood charcoal powder in the formation of a
green body that will be processed into a silicon carbide material (Ans. 5
(citing Gupta col. 2, ll. 12-15)). Appellants argue that Gupta does not
contain a teaching or suggestion to modify Brun’s process by using a wood
charcoal powder to create the preform (App. Br. 13). In particular,
Appellants suggest that Gupta is not relevant to the claimed invention
because Gupta discusses the manufacture of porous silicon carbide bodies
rather than high density ceramics (id.). As the Examiner argues (Ans. 20-
21), however, Gupta discusses making silicon carbide-containing ceramics
by using wood charcoal powder as a starting material. Because the Examiner
only relies upon Gupta for this limited purpose, Appellants arguments are
not persuasive.
Third, while neither Brun nor Gupta describe the manufacture of a
silicon carbide-containing ceramic that has density in excess of 2.8 g/cm3,
the Examiner found that a person of ordinary skill in the art would have had
a reasonable expectation of success in creating such a ceramic (Ans. 20-21).7
As the Examiner notes, Gupta describes the manufacture of porous silicon
carbide bodies with densities as high as 2.5 g/cm3. Gupta col. 3, ll. 25-33.
Appellants do not provide any evidence or argument to rebut the Examiner’s
finding that a person of ordinary skill in the art would have found it obvious

7 For purposes of our decision, we assume, but do not decide, that
Appellants’ recitation of the geometric density of the silicon-carbide
containing ceramic is a claim limitation even though it only appears in the
preamble of claim 1. Absent special circumstances, the preamble of a claim
is presumed not to be limiting. See, e.g., Rowe v. Dror, 112 F.3d 473, 478
(Fed. Cir. 1997).
Appeal 2011-009984
Application 11/636,742
6
to create higher density silicon carbide-containing ceramics. We do not
discern any error in the Examiner’s finding.
For the foregoing reasons, we affirm the Examiner’s rejection of
claim 1 of the ’742 application.
Rejections 2-8. Appellants argue that these rejections are erroneous
for the reasons that we addressed in our discussion of Rejection 1. As above,
we do not find Appellants’ arguments persuasive. We also affirm these
rejections.
CONCLUSION
We affirm the Examiner’s rejections of claims 1-20 of the ’742
application.

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

AFFIRMED

kmm