Ex Parte Knudsen et al

Board of Patent Appeals and Interferences

May 17, 2012

12057853 (B.P.A.I. May. 17, 2012)

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.
12/057,853 03/28/2008 Ronald D. Knudsen 210453US04 (4081-04429) 2075
37814 7590 05/17/2012
CHEVRON PHILLIPS CHEMICAL COMPANY
5601 Granite Parkway, Suite 750
PLANO, TX 75024
EXAMINER
MCDONOUGH, JAMES E
ART UNIT PAPER NUMBER
1731
MAIL DATE DELIVERY MODE
05/17/2012 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 BOARD OF PATENT APPEALS
AND INTERFERENCES
________________

Ex parte RONALD D. KNUDSEN,
Bruce E. Kreischer, Ronald G. Abbott, and Steven D. Bridges
________________

Appeal 2010-008434
Application 12/057,853
Technology Center 1700
________________

Before FRED E. McKELVEY, MARK NAGUMO, and
RICHARD M. LEBOVITZ, Administrative Patent Judges.

NAGUMO, Administrative Patent Judge.

DECISION ON APPEAL
Appeal 2010-008434
Application 12/057,853

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A. Introduction1
Ronald D. Knudsen, Bruce E. Kreischer, Ronald G. Abbott, and
Steven D. Bridges (“Knudsen”) timely appeal under 35 U.S.C. § 134(a) from
the final rejection2 of claims 1, 2, 4-6, 8-12, and 14-22, which are all of the
pending claims. We have jurisdiction. 35 U.S.C. § 6. We REVERSE.
The subject matter on appeal relates to a method of making an olefin
oligomerization catalyst based on a chromium-pyrrole compound. The
catalyst is said to be especially useful for the production of 1-hexene from
ethylene.3 (Spec. 1 [0001].) According to the 853 Specification, the activity
and specificity of the catalyst can be improved markedly by “abating” the
presence of water or other active hydrogen compounds. The reactions of
such active-hydrogen compounds with various components of the catalyst
are said to lead to the formation of potentially corrosive by-products, such as
hydrogen halides (id. at 12 [0031]) as well as precipitates that may lead to
undesired reactions, such as the formation of high polymer (id. at [0032]).
The 853 Specification teaches that abatement is advantageously conducted
by treating a composition containing the chromium compound with a non-
halide metal alkyl compound, such as triethylaluminum (“TEA”), prior to

1 Application 12/057,853, Methods of Preparation of an Olefin
Oligomerization Catalyst, filed 28 March 2008 as a continuation of an
application filed 20 February 2004 (now abandoned). The specification is
referred to as the “853 Specification,” and is cited as “Spec.” The real party
in interest is listed as Chevron Phillips Chemical Co. (Appeal Brief,
filed 3 February 2010 (“Br.”), 3.)
2 Office action mailed 3 August 2009 (“Final Rejection”; cited as “FR”).
3 1-Hexene is copolymerized with ethylene to make, e.g., the flexible
“polyethylene” films used for wrapping packages.
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Application 12/057,853

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treatment with metal halide-containing compounds such as diethylaluminum
chloride (“DEAC”). (Id. at 1-2 [0004].) However, because chromium may
react with the non-halide metal alkyl compound to form a gel, it is desirable
to maintain a relatively low concentration of the non-halide metal alkyl
compound relative to the chromium compound. (Id. at 14 [0035]
to 16 [0036].) In some versions of the process, the abated compositions may
be filtered to remove any precipitates that may have formed. (E.g., id.
at 17 [0039]-[0040].)
Representative Claim 1 reads:
1. A method of oligomerizing olefins, comprising:
(A) preparing an oligomerization catalyst, wherein:
(i) the catalyst comprises a chromium-containing
compound, a pyrrole-containing compound, a non-
halide metal alkyl, a metal halide-containing
compound, and optionally a solvent, and
(ii) the catalyst is prepared by:
(a) contacting a composition comprising the
chromium-containing compound with a portion
of the non-halide metal alkyl such that the molar
ratio of non-halide metal alkyl to chromium-
containing compound is less than about 1.5:1,
and
(b) subsequently contacting the components
from (a) with a composition comprising the metal
halide-containing compound and the remaining
components of the catalyst compound including
an additional amount of the non-halide metal
alkyl; and
(B) oligomerizing olefins by contact with the catalyst in a
reaction zone.
(Claims App., Br. 26; indentation, paragraphing, and emphasis added.)
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The Examiner maintains the following grounds of rejection:4,5
A. Claims 1, 2, 4, 9-12, and 14-21 stand rejected under
35 U.S.C. § 103(a) in view of the combined teachings of
Reagen6 and Manzer.7
B. Claims 5, 6, 8, and 22 stand rejected under 35 U.S.C. § 103(a)
in view of the combined teachings of Reagen, Manzer, and
Kreischer.8
C. Claims 1, 2, 4-6, 8-12, and 14-22 stand rejected under
obviousness-type double patenting in view of Ewert 6129
claims 1-49.

4 Examiner’s Answer mailed 9 March 2010 (“Ans.”).
5 The rejection of claims 1, 2, 4-6, 8-12, and 14-22 under obviousness-type
double patenting in view of Knudsen, U.S. Patent 7,384,866, claims 1-61, is
moot in view of the terminal disclaimer filed 4 February 2010, and approved
23 March 2010.
6 William K. Reagen et al., Chromium Catalysts and Process for Making
Chromium Catalysts, U.S. Patent 5,376,612 (1994).
7 Leo Ernest Manzer, 2-Dialkylaminobenzyl and 2-Dialkylaminomethyl-
phenyl Derivatives of Selected Transition Metals, U.S. Patent 4,057,565
(1977).
8 Bruce E. Kreischer et al., Methods for Restoring the Heat Transfer
Coefficient of an Oligomerization Reactor, U.S. Patent 6,380,451 B1 (2002).
9 Warren M. Ewert et al., Olefin Polymerization Process, U.S.
Patent 7,157,612 B2 (2 January 2007), based on an application
filed 18 June 2004.
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B. Discussion
Findings of fact throughout this Opinion are supported by a
preponderance of the evidence of record.
The claimed invention
According to the plain language of claim 1, catalyst preparation
steps (i) and (ii) must be performed in order. Moreover, as Knudsen argues
(Br., para. bridging 13-14, last sentence), notwithstanding the “open”
transitional phrase “comprising,” initial step (a) does not admit the presence
of metal-halide containing compound, because that would defeat the purpose
of the invention.10 The subsequent contacting step recited in step (b)
requires that the components from step (a) be contacted with the remaining
components of the catalyst recited in condition (i), including, in particular,
the metal halide-containing compound, and an additional amount of the non-
halide metal alkyl compound.
The rejections
The Examiner finds that Reagen describes an oligomerization catalyst
that contains all the ingredients recited in claim 1, and a generally similar
method of making and using the catalyst. (Ans. 3.) Although the Examiner
finds that Reagen “does not teach this double addition of non-halide metal
alkyl” as recited in steps (a) and (b) of the claimed method, the Examiner
finds that Reagen does teach that “the components can be combined in any
manner that forms an effective catalyst.” (Id. at last para., citing Reagen

10 By extension, we assume, without deciding, that step (a) also excludes the
presence of the other catalyst components recited in condition (i).
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col. 15, ll. 55-64.) The Examiner finds further that the skilled artisan would
have appreciated that “the non-halide metal alkyl would be [sic: would have
been] desired to be added to remove any moisture or acidic protons before
the addition of the metal halide containing composition to prevent the
formation of hydrogen halide and/or degeneration of the catalyst.” (Id.
at para. bridging 3-4.) In support of this finding, the Examiner finds that
Manzer teaches the use of organoaluminum compounds to “remove trace
water from compounds analogous to those of the present claims.” (Id. at 5,
1st full para., citing Manzer col 6, ll. 35-44.) The Examiner concludes that
the “double addition” would have been obvious because “taking what was
originally one step and splitting it into two steps is prima facie [sic] 11
obvious absent any evidence of unexpected results or criticality.” (Id. at 4,
ll. 2-4; emphasis added.)
Similarly, the Examiner finds that although the claims of Ewert do not
recite two additions of the non-halide metal alkyl, the presently claimed
invention would have been obvious because “the separation of what was
originally one step into two steps is considered to be prima facie obvious
absent any evidence of criticality or unexpected results.” (Ans., para.
bridging 9-10, last sentence.)
For the reasons argued by Knudsen (Br. 9-15), the Examiner has
failed to establish a prima facie case of obviousness. First, the Examiner has

11 This use of the term “prima facie” (or the phrase “absent any evidence
. . . ”) is redundant. The phrase “prima facie” means “at first sight; on first
appearance but subject to further evidence or information.” (Black’s Law
Dictionary, 9th Ed.; emphasis added.)
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not directed our attention to any specific teaching in Reagen or the other
prior art relied on that supports the Examiner’s finding that the artisan would
have considered the addition of a non-halide metal alkyl compound prior to
the addition of a metal halide compound to be useful for the reasons given
by Knudsen in the present 853 Specification. Nor has the Examiner directed
our attention to any other credible evidence supporting some other reason for
altering the course of the processes described by Reagen. Reagen’s general
statement that “[t]he reactants can be combined in any manner under
conditions suitable to form an effective catalyst system” is a truism: what
works, works. As such, it cannot be considered a general instruction that
every manner of combination can be expected to be successful.
Second, the Examiner has not come forward with any credible
evidence that the artisan would have considered the specific “splitting of one
step into two steps,” with the specific order of addition of components
required by appealed claim 1, to be obvious. The mere reliance on a general
rule, without demonstrating its applicability in a particular case, is the sort of
per se reliance that our reviewing court has criticized repeatedly. See, e.g.,
In re Ochiai, 71 F.3d 1565, 1572 (Fed. Cir. 1995) (the PTO must establish
that “the invention as claimed in the application is obvious over cited prior
art, based on the specific comparison of that prior art with claim limitations.
We once again hold today that our precedents do not establish any per se
rules of obviousness, just as those precedents themselves expressly declined
to create such rules.”). The transition-metal catalyzed oligomerization and
polymerization of olefins remains a notoriously unpredictable art
nearly 60 years after the introduction of the so-called Ziegler-Natta catalysts,
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of which the present chromium catalyst is a species. The application of the
Examiner’s proposed “rule” of obviousness requires a demonstration that the
particular process described in the prior art would have been sufficiently
predictable at the time the invention was made, that persons having ordinary
skill in the art would have had a reasonable expectation of successfully
modifying the process for the reasons proposed. Examiner’s arguments to
the contrary (Ans. 12-14) notwithstanding, the Examiner has failed to
provide such a demonstration.
The Examiner’s reliance on generalities, rather than specifics, is
highlighted by the absence of reference to any specific examples of prior art
processes, or, in the case of the obviousness-type double patenting rejection,
by the absence of reference to any specific claims of Ewert.12 In other
words, the Examiner has not come forward with a specific process described
by Reagen, or even a specific claim of Ewert, and explained why the specific
modifications that would have led to a process within the scope of the
present claim would have been obvious. Cf. Takeda Chem. Indus., Ltd. v.
Alphapharm Pty, Ltd., 492 F.3d 1350, 1356-57 (Fed. Cir. 2007) (holding
that the failure to come forward with evidence that a lead compound would
have been selected for modification to obtain improved properties negatived
the conclusion of obviousness).
The Examiner’s further reliance on Kreischer in the rejection of
claims 5, 6, 8, and 22 (which recite the use of an alcohol to kill the catalyst)
does not cure the noted deficiencies of the principal rejection.

12 Independent claims 1, 40, and 49 of Ewert do not mention the presence of
the metal halide compound required by the appealed claims.
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In the absence of a prima facie case of obviousness, we need not
consider the proferred arguments and supporting evidence for unexpected
results.
C. Order
We REVERSE the rejection of claims 1, 2, 4, 9-12, and 14-21 under
35 U.S.C. § 103(a) in view of the combined teachings of Reagen and
Manzer.
We REVERSE the rejection of claims 5, 6, 8, and 22 under
35 U.S.C. § 103(a) in view of the combined teachings of Reagen, Manzer,
and Kreischer.
We REVERSE the rejection of claims 1, 2, 4-6, 8-12, and 14-22 under
obviousness-type double patenting in view of Ewert 612 claims 1-49.
REVERSED

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