Ex parte GEORGES et al.

Board of Patent Appeals and Interferences

Sep 25, 1997

08037192 (B.P.A.I. Sep. 25, 1997)

Application for patent filed March 25, 1993.1
Claim 24 is dependent on claim 1. Although the examiner indicated in2
an advisory action dated December 3, 1993 (Paper No. 7) that this claim was
allowed, it should have been objected to because it is dependent upon a
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was not written for publication in a law journal and (2) is not
binding precedent of the Board.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. 13
UNITED STATES PATENT AND TRADEMARK OFFICE
__________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
__________
Ex parte MICHAEL K. GEORGES and RAJ D. PATEL
__________
Appeal No. 95-1079
Application 08/037,1921
__________
ON BRIEF
__________
Before GARRIS, WEIFFENBACH and WALTZ, Administrative Patent
Judges.
WEIFFENBACH, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on appeal under 35 U.S.C. § 134 from the
examiner's final rejection of claims 1-23 and 25-49. The only
other claim in the application, dependent claim 24, stands
allowed. We affirm.2
Appeal No. 95-1079
Application 08/037,192
rejected claim. See Section 608,01(n) of the Manual of Patent Examining
Procedure, 6th Edition, Rev. July 1996, page 600-61.
2
The Claimed Subject Matter
The claims on appeal are directed to a process for preparing
a suspension of submicron size polymeric particles for use as
powder coatings or in toner compositions. Claims 1 and 35 are
illustrative of the claimed subject matter:
1. A process for the preparation of a polymer
comprising: effecting bulk polymerization of a mixture
comprised of at least one monomer, a free radical
polymerization initiator, and a stable free radical
agent until from about 10 to about 50 weight percent of
the monomer has been polymerized to form a bulk
polymerization product; optionally adding additional
free radical initiator to said bulk polymerization
product; optionally adding a colorant to said bulk
polymerization product; dispersing said bulk
polymerization product with a high shear mixer into
water containing a stabilizing component selected from
the group consisting of non-ionic and ionic water
soluble polymeric stabilizers to obtain a suspension of
particles or droplets comprised of said bulk
polymerization product with said particles having an
average diameter of from about 0.1 to about 10 microns;
and polymerizing the resulting bulk polymerization
product suspension in water to form said polymer.
35. A process for the preparation of polymeric
particles useful for powder coating which comprises:
effecting bulk polymerization of a mixture of at least
one monomer, a free radical polymerization initiator,
and a stable free radical agent until from about 10 to
about 50 weight percent of the monomer has been
polymerized; optionally adding additional free radical
initiator; optionally adding a colorant; dispersing
with a high shear mixer the aforementioned partially
Appeal No. 95-1079
Application 08/037,192
3
polymerized product in water containing a stabilizing
component to obtain a suspension of particles or
droplets with an average diameter of from about 0.1 to
about 10 microns; and polymerizing the resulting
suspension to form polymeric particles.
The Rejection
The following prior art reference is relied upon by the
examiner to support the rejection of the claims:
Mahabadi et al. (Mahabadi) 5,043,404 Aug. 27, 1991
Claims 1-23 and 25-49 stand rejected under 35 U.S.C. § 103
as being unpatentable over Mahabadi.
Opinion
Appellants state that the claims are to be grouped as
follows:
Group I: claims 1-23, 25-34 and 41-49.
Group II: claims 35-40.
Accordingly, claims 2-23, 25-33 and 41-49 will stand or fall with
claim 1 and claims 36-40 will stand or fall with claim 35. Claim
34 is separately considered infra.
Appeal No. 95-1079
Application 08/037,192
4
We have carefully considered the respective positions
advanced by appellants and the examiner. For the reasons set
forth below, we will sustain the examiner's rejection.
Mahabadi discloses a process for the preparation of a
suspension of submicron polymeric particles comprising the steps
of (a) effecting partial bulk polymerization (10 to about 50%) of
a mixture comprising at least one monomer, a free radical
polymerization initiator, a crosslinking component and a chain
transfer component, (b) dispersing the bulk polymerization
product in water with a high shear mixer containing a stabilizing
component (e.g. non-ionic or ionic water soluble polymeric
stabilizers) to obtain a suspension of particles or droplets
having a diameter from about 0.1 to about 5.0 microns; and (c)
polymerizing the suspension to complete the conversion of monomer
to polymer (col. 3, lines 6-44). The resultant submicron
polymeric particles produced by Mahabadi’s process are useful as
powder coatings or as toner additives (col. 2, lines 27-38).
The prior art reference differs from the claimed subject
matter in that Mahabadi does not disclose the use of a stable
free radical agent to control molecular weight distribution
Appeal No. 95-1079
Application 08/037,192
According to appellants, these properties include: “extent of monomer3
to polymer conversion or degree of a polymerization; control of molecular
weight and polydispersity of the bulk product; viscosity of the bulk product;
temperature profile control, that is the absence of large exotherms; and gel
control or minimization of gel body formation” (specification, page 9).
The term “polydispersity” has not been defined in appellants’4
specification. The closest dictionary definition we could find was in The Van
Nostrand Chemist’s Dictionary, Edited by Honig et al., D. Van Nostrand
Company, Inc., New York, 1953, page 548 which defined a “polydisperse system”
as being a “colloidal system that consists of particles of different sizes.”
From this definition we construe the meaning of “polydispersity properties” in
the context of appellants’ specification to mean a system of polymers having
different properties such as molecular weight, viscosity, degree of
polymerization, etc.
We note that appellants incorporated the Mahabadi patent by reference5
in its entirety into their specification (see page 3) and included a brief
overview of Mahabadi’s process. At least at the time the application was
filed, appellants placed no emphasis on any difference in the function of
Mahabadi’s chain inhibitor and their “stable free radical agent” which would
patentably distinguish their process over the Mahabadi process.
5
properties or what appellants term as “polydispersity.” The3 4
examiner maintains that Mahabadi’s chain transfer component in
step (a) is essentially appellants’ stable free radical agent
because the “stable free radical agent is defined by appellant
[sic, appellants] on page 13 of the specification as free radical
polymerization inhibitors ...” (answer, page 3). Appellants
contend that Mahabadi’s chain transfer agents function as
polymerization inhibitors, and not as agents to control the
molecular weight distribution properties of the polymer. 5
Appellants argue that
[s]ubstituting the chain transfer agents recited in
Mahabadi for the stable free radical agents of the
Appeal No. 95-1079
Application 08/037,192
6
present invention would not enable the polymeric
products with the desired molecular weight and
polydispersity properties of the present invention as
disclosed and claimed. Use of chain transfer agents
would preclude access to narrow polydispersity
polymeric products and higher molecular weight
products, since these agents limit chain growth by
irreversible chain termination and “transfer” of the
free radical species, for example, to a non-reactive
species. [Brief, page 5; emphasis in the original.]
The examiner asserts that appellants are arguing limitations
(e.g. control of polydispersity) which are outside the scope of
the claims.
Our analysis begins with the meaning of the term “stable
free radical agents” in the claims on appeal. The terminology in
a pending claim is to be interpreted as broadly as reasonably
possible. In re Zletz, 893 F.2d 319, 321, 13 USPQ2d 1320, 1322
(Fed. Cir. 1989). It is well settled that claim language is not
considered in a vacuum, but in light of the supporting
specification and teachings of the prior art as it would be
interpreted by one having ordinary skill in the relevant art.
In re Sneed, 710 F.2d 1544, 1548, 218 USPQ 385, 388 (Fed. Cir.
1983); In re Kroekel, 504 F.2d 1143, 1146, 183 USPQ 610, 612
(CCPA 1974); In re Moore, 439 F.2d 1232, 1235, 169 USPQ 236, 238
(CCPA 1971). We therefore look to appellants’ specification for
the meaning of the term “stable free radical agent.”
Appeal No. 95-1079
Application 08/037,192
7
Appellants disclose that the stable free radical agents
employed in the claimed process are well known in the art and
that they have been “used to reversibly cap the ends of growing
chains to produce oligomers ...” (specification, page 13).
According to appellants, the
... stable free radical agents function as moderators
to harness the normally highly reactive and indis-
criminate intermediate growing polymer chain free
radical species as thermally labile covalent adducts
comprised of an oligomer or incipient polymer product
and a stable free agent. The rate at which these
adducts homolytically cleave back into a free radical
terminated polymer chain and a stable free radical is
believed to be a rate limiting step which regulates the
addition of monomer to the growing chain and which
precludes premature chain termination which termination
would ordinarily yield polymer products having broad
polydispersities. Also, under the polymerization
conditions of the present invention, all chains are
initiated at about the same time. Initiating all the
chains at about the same time and limiting the rate of
addition of monomer to the growing chains allows the
bulk polymerization stage to be stopped or suspended,
in a highly reproducible manner, at the aforementioned
desired levels of monomer to polymer conversion.
... If the [molar ratio of stable free radical
agent to free radical initiator] is too high then the
reaction rate is noticeably inhibited. If the [molar
ratio of stable free radical agent to free radical
initiator] is too low then the reaction product has
undesired increased polydispersity. [Specification,
page 14.]
From what appellants have described, we find a reasonable basis
for the examiner to conclude that the functions associated with
appellants’ “stable free radical agent” overlap with the
Appeal No. 95-1079
Application 08/037,192
8
functions of Mahabadi’s chain inhibitor. According to Mahabadi,
the primary function of the chain inhibitor is “to control
molecular weight by inhibiting chain growth” (col. 5, lines 36-
42). Appellants’ “stable free radical agent” also appears to be
controlling molecular weight by inhibiting chain growth.
Appellants have disclosed the agent has been used to “cap the
ends of growing [polymer] chains.” This would reasonably infer
to one skilled in the art that the molecular weight of the
polymer is being controlled since capping the chain necessarily
limits any indiscriminate growth of the polymer chain thereby
regulating the addition of monomers to the growing chain. Since
Mahabadi’s process, like appellants’ claimed process, requires an
initial partial bulk polymerization of the polymer mixture, it is
reasonable to attribute the partial polymerization in Mahabadi’s
process to the inclusion of the chain inhibitor in the monomer
mixture.
Finally, it is noted that claim 34 is a product by process
claim. The patentability of this claim is based on the product
itself. See In re Thorpe, 777 F.2d 695, 697, 227 USPQ 964, 966
(Fed. Cir. 1985); In re Brown, 459 F.2d 531, 535, 173 USPQ 685,
688 (CCPA 1972). Since we find appellants’ claimed process to be
unpatentable, it necessarily follows that the product made by the
Appeal No. 95-1079
Application 08/037,192
9
process is also unpatentable. We also find that the product
defined by claim 34 is indistinguishable from the product
produced by Mahabadi. Apellants have not presented any objective
evidence to show that the products are different. In re Best,
562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977).
Accordingly, for the reasons given above, the decision of
the examiner is affirmed.
Appeal No. 95-1079
Application 08/037,192
10
No time period for taking any subsequent action in
connection with this appeal may be extended under 37 CFR
§ 1.136(a).
AFFIRMED
BRADLEY R. GARRIS )
Administrative Patent Judge)
)
)
)
CAMERON WEIFFENBACH ) BOARD OF PATENT
Administrative Patent Judge) APPEALS AND
) INTERFERENCES
)
)
THOMAS A. WALTZ )
Administrative Patent Judge)
Appeal No. 95-1079
Application 08/037,192
11
Ronald Zibelli
Xerox Corporation
Xerox Square 020
Rochester, NY 14644