Ex parte Purinton et al.

Board of Patent Appeals and Interferences

Aug 18, 1999

08273040 (B.P.A.I. Aug. 18, 1999)

Application for patent filed July 8, 1994. 1
THIS OPINION WAS NOT WRITTEN FOR PUBLICATION
The opinion in support of the decision being entered
today (1) was not written for publication in a law
journal and (2) is not binding precedent of the
Board.
Paper No. 22
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________
Ex parte DONALD L. PURINTON and LOUIS R. SEMFF
____________
Appeal No. 97-1417
Application No. 08/273,0401
____________
ON BRIEF
____________
Before JOHN D. SMITH, HANLON, and ROBINSON, Administrative
Patent Judges.
HANLON, Administrative Patent Judge.
DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 from the final
rejection of claims 1-19 and 21, all of the claims pending in
the application. Claim 1 is illustrative of the subject
matter on appeal and reads as follows:
1. A radome comprising:
Appeal No. 97-1417
Application No. 08/273,040
2
(a) an exterior wall, said wall including:
(i) a central region of porous material
comprising a ceramic material impregnated with an inorganic
resin and having a pair of opposing exterior surfaces; and
(ii) a skin overlying each of said opposing surfaces
to form a composite structure, said skin comprising a first
cloth of ceramic material impregnated with an inorganic resin
which, under pyrolysis, provides an elemental carbon-free
material and, with increased temperature, gradually converts
from the liquid state to a resilient state and then to a solid
state by about 1200°F.
The references relied upon by the examiner are:
Boyd et al. (Boyd) 5,134,421 Jul. 28,
1992
Liimatta et al. (Liimatta) 5,198,152 Mar. 30,
1993
The sole issue on appeal is whether the examiner properly
rejected claims 1-19 and 21 under 35 U.S.C. § 103 as being
unpatentable over the combination of Boyd and Liimatta.
Discussion
Claim 1 is directed to a radome comprising an exterior
wall including:
(1) a central region of porous material comprising a
ceramic material impregnated with an inorganic resin and
having a pair of opposing exterior surfaces; and
Appeal No. 97-1417
Application No. 08/273,040
3
(2) a skin overlying each of the opposing surfaces
whereby the skin comprises a ceramic material impregnated with
an inorganic resin which, under pyrolysis, provides an
elemental carbon-free material and, with increased
temperature, gradually converts from the liquid state to a
resilient state and then to a solid state by about 1200EF.
The inorganic resin is preferably a polysilazane or a
polysiloxane (Specification, p.3).
According to the examiner (Answer, p.3):
Boyd et al discloses a radome comprising a honeycomb
or foam layer laminated with face sheets of resin
impregnated-fiber reinforced material and the use of
ceramic materials for these layers; see column 2,
lines 18-40 and the paragraph bridging columns 5 and
6. However, Boyd et al do not disclose the
particular claimed materials used to form the fiber
reinforced layers . . . . Liimatta et al discloses
the use of polysilizane [sic, polysilazane]
materials as an infiltrant in ceramic fiber
reinforced composites which may be used in radomes;
see column 1, lines 13-18 and 49-50, column 2, lines
65-67 and column 4, lines 42-49.
The examiner continues (Answer, p.4):
Ii [sic, It] is the examiner's position that since
Liimatta et al disclose the same impregnate as that
disclosed by appellant, namely polysilizane [sic,
polysilazane], that the claimed property under
Appeal No. 97-1417
Application No. 08/273,040
4
pyrolysis is inherent in the Liimatta et al
impregnate.
However, appellants argue that the polysilazanes in
Liimatta are not the same as those claimed. More specifically
(Brief, pp.5-6):
Claim 1 requires a skin comprising a first cloth
of ceramic material impregnated with an inorganic
resin which, under pyrolysis, provides an elemental
carbon-free material and, with increased
temperature, gradually converts from the liquid
state to a resilient state and then to a solid state
by about 1200EF. Even further, nowhere in Liimatta
et al. is there a teaching or even a suggestion that
the materials taught therein are limited to those
"which, under pyrolysis, provides an elemental
carbon-free material and, with increased
temperature, gradually converts from the liquid
state to a resilient state and then to a solid state
by about 1200EF". [Emphasis added.]
Manifestly, the resins disclosed in Liimatta are organic.
According to Liimatta, the disclosed invention is directed to
(Abstract):
A crosslinkable preceramic composition suitable for
use as an infiltrant for porous ceramics, such as
fiber-reinforced ceramic composites, comprises about
75-99% by weight of a low molecular weight
polysilazane and about 1-25% by weight of an
unsaturated organic or organosilicon compound
containing at least two alkenyl groups, preferably
methylvinylcyclosilazane.

Appeal No. 97-1417
Application No. 08/273,040
Claims 2-19 and 21 are dependent on independent2
claim 1. See 37 CFR § 1.75(c) ("Claims in dependent form
shall be construed to include all the limitations of the claim
incorporated by reference into the dependent claim.").
5
The examiner has failed to explain how the organic
compositions disclosed in Liimatta provide an elemental
carbon-free material under pyrolysis. Absent a more factually
specific statement of the rejection, we cannot sustain the
rejection of claims 1-19 and 21 under 35 U.S.C. § 103 as2
being unpatentable over the combination of Boyd and Liimatta.
See In re Oetiker, 977 F.2d 1443, 1445, 24 USPQ2d 1443, 1444
(Fed. Cir. 1992) (the examiner bears the initial burden of
presenting a prima facie case of unpatentability).
Based on the record before us, the decision of the
examiner is reversed.
REVERSED
Appeal No. 97-1417
Application No. 08/273,040
6
JOHN D. SMITH )
Administrative Patent Judge )
)
)
)
) BOARD OF PATENT
ADRIENE LEPIANE HANLON ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
DOUGLAS W. ROBINSON )
Administrative Patent Judge )
lp
Appeal No. 97-1417
Application No. 08/273,040
7
GLENN H. LENZEN
RAYTHEON COMPANY
OFFICE OF GENERAL COUNSEL
141 SPRING STREET MAIL STOP 1-1
LEXINGTON, MA 02173
Leticia
Appeal No. 97-1417
Application No. 08/273,040
APJ HANLON
APJ ROBINSON
APJ JOHN D. SMITH
DECISION:
Send Reference(s): Yes No
or Translation (s)
Panel Change: Yes No
Index Sheet-2901 Rejection(s): _____
Prepared: April 13, 2000
Draft Final
3 MEM. CONF. Y N
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