Ex Parte Hofmann et al

Board of Patent Appeals and Interferences

May 18, 2012

10924119 (B.P.A.I. May. 18, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte JORG HOFMANN, STEPHAN EHLERS, BERND KLINKSIEK,
THORSTEN FECHTEL, MATTHIAS RUHLAND, JURGEN SCHOLZ,
FRANZ FOHLES, and ULRICH ESSER
____________

Appeal 2011-007823
Application 10/924,119
Technology Center 1600
____________

Before Eric B. Grimes, Lora M. Green, and Richard M. Lebovitz,
Administrative Patent Judges.

Lebovitz, Administrative Patent Judge.

DECISION ON APPEAL
This is a decision on the appeal under 35 U.S.C. § 134 by the Patent
Applicant from the Patent Examiner’s rejections of claims 12-15 and 21-24
in U.S. Application 10/924,119. The Board’s jurisdiction for this appeal is
under 35 U.S.C. § 6(b). We affirm.

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STATEMENT OF THE CASE
Claims 12-15 and 21-24 are pending and on appeal. All the pending
claims stand rejected by the Examiner under 35 U.S.C. § 103(a) as obvious
in view of Le-Khac ‘428,1 Le-Khac ‘908,2 Hoch,3 Hinney,4 and Heckl5
(Answer 4). As the claims were not argued separately, we select claim 12 as
representative. Claims 13-15 and 21-24 fall with claim 12. 37 CFR
§ 41.37(c)(1)(vii). Claim 12 reads as follows:
A process for preparing a double-metal cyanide catalyst comprising:
combining with a jet disperser in the presence of at least one organic
complexing ligand selected from the group consisting of ethanol,
isopropanol, n-butanol, iso-butanol, sec-butanol, and tert-butanol,
(a) at least one aqueous solution of at least one metal salt selected
from the group consisting of zinc chloride, zinc bromide, zinc
acetate; zinc acetylacetonate, zinc benzoate, zinc nitrate, iron(III)
sulfate, iron(II) bromide, iron(II) chloride, cobalt(II) chloride,
cobalt(II) thiocyanate, nickel(II) chloride and nickel(II) nitrate;
with
(b) at least one aqueous solution of at least one metal cyanide salt
selected from the group consisting of potassium
hexacyanocobaltate(III), potassium hexacyanoferrate(II), potassium
hexacyanoferrate(III), calcium hexacyanocobaltate(III) and lithium
hexacyanocobaltate(III);
to form a double-metal cyanide catalyst dispersion;

filtering the double-metal cyanide catalyst dispersion through a
membrane filter press to obtain a filter cake;

1 U.S. Patent 5,714,428 (issued Feb. 3, 1998).
2 U.S. Patent 5,482,908 (issued Jan. 9, 1996).
3 U.S. Patent 6,103,786 (issued Aug. 15, 2000).
4 U.S. Patent 5,158,922 (issued Oct. 27, 1992).
5 U.S. Patent 6,387,282 B1 (issued May 14, 2002).
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washing the filter cake in the membrane filter press at least once with the
at least one organic complexing ligand by a flow-through washing of the
filter cake;
mechanically removing moisture in the washed filter cake; and

drying the filter cake.

THE REJECTION
Claim 12 is drawn to a process of preparing a double-metal cyanide
catalyst. The claimed method comprises “combining with a jet disperser” an
organic complexing ligand with an aqueous solution of at least one metal
salt and at least one metal cyanide salt “to form a double-metal cyanide
catalyst dispersion.” The dispersion is filtered “through a membrane filter
press to obtain a filter cake,” washed, moisture is “mechanically” removed
from the cake, and then the filter cake is dried. The Examiner found that Le-
Khac ‘428 described almost all the operative steps of the claimed method
(Answer 4), but not using a “jet disperser” or a “membrane filter press” (id.
at 5). To meet the latter limitations, the Examiner cited Hoch, Hinney, and
Heckl (id. at 5-6).
The Examiner found that Hoch taught preparing dispersions with a jet
disperser. The Examiner concluded it would have been obvious to use a jet
disperser in Le Khac’s method “since Hoch et al. teach that jet dispersers
have a much higher degree of efficiency than high-pressure homogenizers,
which would be desirable in the process of Le-Khac ‘428 in order to more
efficiently incorporate the organic complexing agent into the catalyst
framework.” (Answer 5.)
Hinney and Heckl were cited by the Examiner for their disclosure of
filter presses. Hinney was characterized by the Examiner as describing a
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process of preparing a double-metal cyanide catalyst in which a filter press
was used to prepare a filter cake (Answer 6). Heckl was cited for describing
a filter press which has a membrane as a filter medium (id.). The Examiner
concluded that it would have been obvious to have used a membrane filter
press in Le-Khac ‘428’s method based on (1) Le-Khac’s teaching that any
convenient means of separating the double-metal cyanide catalyst could be
utilized in its process, (2) Hinney’s teaching of a filter press as a suitable
filtering apparatus for separating a double metal cyanide catalyst from a
slurry, the same type of catalyst described in Le-Khac ‘428; and 3) the
teaching in both Hinney and Heckl that membranes are useful in filter
presses (id. at 6-7).
ANALYSIS
Appellants appeal the Examiner’s determination that the claimed
subject matter would have been obvious in view of Le-Khac ‘428, Le-Khac
‘908, Hoch, Hinney, and Heckl. Appellants’ first argument is that Le-Khac
‘428 utilized a “functionalized polymer or a salt thereof” in its process, and
that without this polymer, catalysts “were difficult to pulverize into a
powder, gelled during synthesis of an 8K diol and did not have the high
polymerization rates of the catalysts produced with a functionalized
polymer.” (App. Br. 4.) Appellants argue that, in contrast, they “have found
a way to produce a DMC [double-metal cyanide] catalyst which has high
polymerization rates without the need to use the functionalized polymer of
Le-Khac ‘428.” (Id. at 5.)
Citing In re Marosi, 710 F.2d 799 (Fed. Cir. 1983), Appellants
contend that it is not obvious to omit an essential ingredient from a process
because “one skilled in the art would expect either that an undesirable
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reaction would occur or that no reaction would occur.” (App. Br. 5).
Appellants contend that Le-Khac ‘428 described the functionalized polymer
as essential, and under the principles of Marosi, it would therefore not have
been obvious to one of ordinary skill in the art to omit it (id. at 6-7).
The Examiner rejected this argument, stating that claim 12 used the
terminology “comprising” to characterize the claimed process, which is
open-ended and does not exclude additional ingredients such as the
functionalized polymer of Le-Khac ‘428 (Answer 7).
The facts in this appeal can be readily distinguished from Marosi. In
Marosi, the claims were directed to a process for the manufacture of a
nitrogen-containing crystalline metal silicate which “comprise[d]” adding “a
silicon dioxide source that is essentially free of alkali metal” to a solution of
other components. Marosi, 710 F.2d at 800-801. The resulting crystalline
metal silicate was also “essentially free of alkali metal.” Id. The process
described in the Rollmann patent was cited against the Marosi claims.
Rollmann, however, required an alkali metal as an essential ingredient. Id.
at 801. Thus, in order to meet all the limitations in the claim, it was
necessary to have a reason to omit the alkali metal from the prior art
Rollmann process. The court held:
The Rollmann et al. process, which requires alkali metal as an
essential ingredient, neither anticipates nor renders obvious
appellants’ process, which requires the practical elimination of
alkali metal. A person of ordinary skill in the art would
reasonably expect that, if what is taught as an essential
ingredient is not included, an undesirable reaction or no
reaction at all would occur.
(Id. at 803.) The claims in Marosi explicitly excluded the alkali metal
described as essential in the Rollmann patent. Because an alkali metal was
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essential, the court concluded that a person of ordinary skill in the art would
not have omitted it to make the claimed invention because there would have
been no reasonable expectation that the claimed reaction would succeed.
Here, the claims do not expressly exclude a functionalized polymer.
Nor have Appellants identified language in the claims that would lead us to
read such exclusion into them. Thus, even were the functionalized polymer
taught by Le-Khac ‘428 an essential component, as the alkali metal was in
Marosi, the present claims do not exclude the polymer, in contrast to the
explicit exclusion in Marosi. Marosi recognized that distinction:
“Appellants have chosen to distinguish their invention from the prior art
with the limitation ‘essentially free of alkali metal.’” Marosi, 710 F.2d at
802. While it may be true that Appellants have a found a method that
“eliminates the need for a functionalized polymer – a finding which is
neither taught nor suggested by Le-Khac ‘428” (Reply Br. 2), such a method
is not presently claimed.
Additionally, Appellants contend that the cited prior art references do
not teach that the jet disperser would eliminate the need for a functionalized
polymer (App. Br. 8) or that a membrane press filter would make it possible
to produce a catalyst with high activity (id. at 9 & 10). These arguments are
not persuasive.
First, as already discussed above, the claims do not exclude the
presence of a functionalized polymer.
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Second, there is no evidence in this appeal that the claimed invention,
utilizing a jet disperser and membrane filter press, produced results which
would have been unexpected to one of ordinary skill in the art.6
Third, the Examiner gave fact-based reasons as to why one of
ordinary skill in the art would have utilized a jet disperser and membrane
filter press in the Le-Khac ‘428 process (see supra; Answer 5-7). Appellants
did not identify an error in the Examiner’s reasoning and we find none.
Because such devices were known in the art, we “must ask whether the
improvement is more than the predictable use of prior art elements according
to their established functions.” KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398,
417 (2007). “The combination of familiar elements according to known
methods is likely to be obvious when it does no more than yield predictable
results.” Id. at 416. In this case, there is inadequate evidence before us that
the use of the jet disperser and membrane filter produced anything more than
predictable results when used according to their established functions.
For the foregoing reasons, we affirm the rejection of claim 12. Claims
13-15 and 21-24 fall with claim 12.

6 Once prima facie obviousness has been established, it can be rebutted with
“a showing of ‘unexpected results,’ i.e., to show that the claimed invention
exhibits some superior property or advantage that a person of ordinary skill
in the relevant art would have found surprising or unexpected.” In re Soni,
54 F.3d 746, 750 (Fed. Cir. 1995). “[W]hen an applicant demonstrates
substantially improved results … and states that the results were unexpected,
this should suffice to establish unexpected results in the absence of evidence
to the contrary.” Soni, 54 F.3d at 751.

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TIME PERIOD FOR RESPONSE
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

KMF