Ex Parte Van Zon et al

Board of Patent Appeals and Interferences

Mar 25, 2008

10668934 (B.P.A.I. Mar. 25, 2008)

UNITED STATES PATENT AND TRADEMARK OFFICE
_______________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
_______________

Ex parte ARIE VAN ZON, ROBERT MOENE,
PHILLIP EDWARD UNGER, PETER ARNOLDY,
and ERIC JOHANNES MARIA DE BOER
______________

Appeal 2008-0162
Application 10/668,934
Technology Center 1700
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Decided: March 25, 2008
_______________

Before BRADLEY R. GARRIS, CHARLES F. WARREN, and
PETER F. KRATZ, Administrative Patent Judges.

WARREN, Administrative Patent Judge.

DECISION ON APPEAL
Applicants appeal to the Board from the decision of the Primary
Examiner finally rejecting claims 1 through 7 in the Office Action mailed
June 13, 2005. 35 U.S.C. §§ 6 and 134(a)(2002); 37 C.F.R. § 41.31(a)
(2006).
We affirm the decision of the Primary Examiner.
Claim 1 illustrates Appellants’ invention of a process for making a
linear alpha-olefin oligomer, and is representative of the claims on appeal:

Appeal 2008-0162
Application 10/668,934
1. A process for making a linear alpha-olefin oligomer in a reactor
comprising a liquid and a gas phase, comprising the steps of catalytically
oligomerizing ethylene in the presence of a complex selected from the group
consisting of nickel, palladium, cobalt, titanium, zirconium, hafnium,
vanadium, chromium, molybdenum, and tungsten complexes, to an alpha-
olefin oligomer under release of heat, and removing the heat with a heat
exchanger which is positioned in the gas phase in the reactor but not in
direct contact with the liquid phase, using at least part of the gas phase as a
coolant medium.
The Examiner relies upon the evidence in these references (Ans. 3):
Hinton US 3,461,109 Aug. 12, 1969
Reagan EP 0 608 447 A1 Aug. 3, 1994
Gibson WO 00/15646 A1 Mar. 23, 2000
Appellants request review of the following grounds of rejection
advanced on appeal (Br. 2-3):
Claims 1 and 3 through 7 under 35 U.S.C. § 103(a) as unpatentable over
Gibson in view of Hinton (Ans. 3); and
Claim 2 under 35 U.S.C. § 103(a) as unpatentable over Gibson in view of
Hinton further in view of Reagan (Ans. 4).
Appellants argue the claims in the first ground of rejection as a group.
Br. 3-4. Appellants further “request that the rejection of claim 2 be
overturned for the reasons discussed . . . in connection with [Gibson] and
[Hinton].” Br. 5. Thus, we decide this appeal based on independent claim 1.
37 C.F.R. § 41.37(c)(1)(vii)(2006).
The issues in this appeal are whether the Examiner has carried the
burden of establishing a prima facie case in each of the grounds of rejection
advanced on appeal.
The plain language of claim 1, with reference to Specification Fig. 2,
specifies a process for making a linear alpha-olefin oligomer in reactor 2
comprising at least liquid phase section 3 and gas phase section 4. The
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Application 10/668,934
process comprises at least the steps of catalytically oligomerizing ethylene in
the presence of a stated complex catalyst under release of heat and removing
the heat with heat exchanger 20 positioned in gas phase section 4 of the
reactor but not in contact with the liquid phase section, wherein at least part
of the gas in the gas phase section is used as a coolant medium. See Spec.
9:14-28. With respect to gas as a coolant medium, Appellants explain “[t]he
reaction heat causes the solvents, reactants, and/or reaction products . . .
present in the reaction medium, to evaporate and subsequently to be cooled
by the heat exchanger, after which it works as a coolant medium for the
reactor” by falling into the liquid phase. Spec 6:3-7 and
9:22-26. We find no basis in the claim language or in the disclosure in the
Specification on which to read such disclosure as a limitation into claim 1.
See, e.g., In re Zletz, 893 F.2d 319, 321-22 (Fed. Cir. 1989).
We find Gibson would have disclosed to one of ordinary skill in this
art a “catalyst for polymerizing and oligomerizing monomers, for example,
olefins such as α-olefins,” including ethylene. Gibson 2:15-19. There is no
dispute that Gibson’s cobalt complex catalyst falls within appealed claim 1.
Gibson discloses methods of conducting gas phase polymerization processes
including the steps of “feeding . . . [to the fluidized catalyst bed] a stream of
monomer at least partially in the gaseous phase . . . such that at least part of
the monomer polymerizes in contact with the catalyst in the bed.” Gibson
12:10-16. “The bed is generally cooled by the addition of cool gas (e.g.,
recycled gaseous monomer) and/or volatile liquid (e.g. a volatile inert
hydrocarbon, or gaseous monomer which has been condensed to form a
liquid).” Gibson 12:16-20 and 14:5-18. The fluidizing gas for the fluidized
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Application 10/668,934
catalyst bed supplies monomer and some inert gas, such as nitrogen or an
alkane, and serves to remove the heat of polymerization from the bed, with
the hot reactor gas “then led to a heat exchanger to remove at least part of
the heat of polymerization” by cooling the reactor gas. Gibson 13:10-23 and
14:1-6. The cooled reactor gas including condensed volatile liquid is
recycled to the bed, with the latter evaporating in the bed and removing heat
therefrom. Gibson 14:5-18. Gibson discloses the amount of liquid in the
gas phase zone is small compared to the amount of polymer present, in
contrast to solution and slurry phase processes. Gibson 12:20-25.
We find Hinton would have disclosed to one of ordinary skill in this
art a process wherein any monomer or monomers
can be solution polymerized to polymer concentrations . . . by
utilizing a reactor which contains a heat transfer surface in the
upper portion thereof and by maintaining a substantially liquid
mixture of monomer, solvent and catalyst in the lower portion
of the reactor below the heat transfer surface and under
polymerization conditions which produce vapors of the solvent
or monomer or both. . . . [T]he temperature in the reactor after
warm-up is maintained at a desired value by removal of the
polymerization heat of reaction through the condensation of the
vapors on the heat transfer surface. The condensed vapors are
allowed to continuously and freely return directly to the mixture
in the lower portion of the reactor.
Hinton col. 1, ll. 38-60. Hinton teaches the reactor can be employed in
continuous-flow polymerization. Hinton col. 3, ll. 67-72. Hinton discloses
that, alternatively, the process “can be practiced with the use of a heat
exchanger external to the reactor with direct and immediate recycle of
condensate to the reactor.” Hinton col. 4, ll. 1-6. “Generally, one or more
polyolefin monomers can be utilized as feed material for this invention.
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However, preferred monomers are dienes, still more preferably conjugated
dienes.” Hinton col. 4, ll. 7-9. Hinton illustrates reactor 2 in which heat
transfer coil 6 is positioned in the gas phase section which is separated from
the liquid phase section by entrainment separator 19. Hinton col. 2, l. 47 to
col. 3, l. 30, and Fig.
We determine the combined teachings of Gibson and Hinton, the
scope of which we determined above, provide convincing evidence
supporting the Examiner’s case that the claimed invention encompassed by
claim 1, as we interpreted this claim above, would have been prima facie
obviousness to one of ordinary skill in the molding arts familiar with the
catalytic polymerization and oligomerization of alpha-olefins, including
ethylene, and the requirements for reactors used to conduct the reactions.
On this record, we agree with the Examiner’s determination that, prima
facie, one of ordinary skill in this art would have used Hinton’s reactor to
conduct the oligomerization reaction of ethylene with the cobalt complex
catalyst taught by Gibson in the reasonable expectation of obtaining the
oligomerized ethylene product. Ans. 3-4. Indeed, this person would have
recognized that Hinton specifies no limitation on the monomers that can be
solution polymerized in the reactor, and that Gibson’s processes can include
feeding partially liquid monomers as well as volatile liquids to the catalyst
bed for cooling purposes, wherein evaporated monomer gases and
volatilized liquids are collected in the reactor and then condensed in a heat
exchanger and recycled to the bed. While Gibson appears to disclose
leading these gases to an external heat exchanger, we determine, as does the
Examiner (Ans. 3), that this person would have further recognized that in
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Gibson’s process, such gases can be condensed in a gas zone of the reactor
for return of liquids therein as a cooling medium to the catalyst bed in the
reaction zone, avoiding the need for an external heat exchanger and recycle
lines. Thus, this person would have further recognized that Hinton’s reactor
with the heat exchanger located in a gas zone above the catalyst bed reaction
zone has the gas zone wherein the zones are separated by an entrainment
separator, can reasonably be used for Gibson’s purposes. Indeed, Hinton
discloses the internal heat exchanger is an alternative to an external heat
exchanger.
Accordingly, we are of the opinion the Examine correctly recognized
that, prima facie, one of ordinary skill in this art routinely following the
combined teachings of Gibson and Hinton would have reasonably arrived at
the claimed process encompassed by claim 1, including all of the limitations
thereof, without resort to Appellants’ Specification. See, e.g., KSR Int’l Co.
v. Teleflex Inc., 127 S. Ct. 1727, 1740-41 (2007) quoting In re Kahn,
441 F.3d 977, 988 (Fed. Cir. 2006)(“[A]nalysis [of whether the subject
matter of a claim would have been obvious] need not seek out precise
teachings directed to the specific subject matter of the challenged claim, for
a court can take account of the inferences and creative steps that a person of
ordinary skill in the art would employ.”); In re Siebentritt, 372 F.2d 566,
567-68 (CCPA 1967)(express suggestion to interchange methods which
achieve the same or similar results is not necessary to establish
obviousness); see also In re O’Farrell, 853 F.2d 894, 903-04, 7 USPQ2d
1673, 1681 (Fed. Cir. 1988)(“For obviousness under § 103, all that is
required is a reasonable expectation of success.” (citations omitted)); In re
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Keller, 642 F.2d 413, 425 (CCPA 1981) (“[T]he test is what the combined
teachings of the references would have suggested to those of ordinary skill
in the art.”); In re Sovish, 769 F.2d 738, 743 (Fed. Cir. 1985) (skill is
presumed on the part of one of ordinary skill in the art); In re Bozek,
416 F.2d 1385, 1390 (CCPA 1969) (“Having established that this knowledge
was in the art, the examiner could then properly rely, as put forth by the
solicitor, on a conclusion of obviousness ‘from common knowledge and
common sense of the person of ordinary skill in the art without any specific
hint or suggestion in a particular reference.’”).
Upon reconsideration of the record as a whole in light of Appellants’
contentions, we are of the opinion that Appellants have not successfully
rebutted the prima facie case. We agree with Appellants’ findings with
respect to the teachings of Gibson (Br. 3:16-27) and we made similar
findings above. However, we disagree with Appellants that Gibson does not
disclose “a discrete liquid phase where most of the reaction takes place and
also a discrete gas phase from which unreacted reaction components and
some reaction products may be condensed” (Br. 3:27-4:12), and with the
further implication in this contention that Gibson’s processes are not
encompassed by claim 1. We are of the view that Gibson’s disclosure of a
partially liquid monomer feed and volatile liquid feed to the catalyst bed and
collection of volatilized liquids leading to a heat exchanger, meets the claim
limitations of a process comprising at least “a liquid phase” and the
evaporation of these liquids in the catalyst bed gives rise to “a gas phase” in
the reactor. In this respect, we determine there is no basis in the claim
language or in the disclosure in the Specification to read a liquid phase
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catalyst reaction as a limitation into claim 1 which excludes a gas phase
reaction from liquid monomer vaporized in the catalyst bed. See, e.g., Zletz,
893 F.2d at 321-22. Indeed, the plain language of claim 1 dose not specify
that the process must be conducted in “a liquid phase” or in “a gas phase.”
Furthermore, contrary to Appellants’ contentions (Br. 4-5), Hinton’s
disclosure of the polymerization of dienes as a preferred use of the reactor
taught therein does not limit the teachings of the reference. See, e.g., In re
Lamberti, 545 F.2d 747, 750 (CCPA 1976) (“[T]he fact that a specific
[embodiment] is taught to be preferred is not controlling, since all
disclosures of the prior art, including unpreferred embodiments, must be
considered.”). Similarly, one of ordinary skill in this art would have
recognized that like Gibson, Hinton’s reactor condenses and recycles
evaporated materials back to the catalytic polymerization medium, and thus,
would have combined the similar references to take advantage of Hinton’s
reactor which condenses the materials in a gas phase zone of the reactor.
See, e.g., Kahn, 441 F.3d at 985-88.
Accordingly, based on our consideration of the totality of the record
before us, we have weighed the evidence of obviousness found in the
combined teachings of Gibson and Hinton with Appellants’ countervailing
evidence of and argument for nonobviousness and conclude that the claimed
invention encompassed by appealed claims 1 and 3 through 7 would have
been obvious as a matter of law under 35 U.S.C. § 103(a).
On this basis we also affirm the ground of rejection of claim 2 under
35 U.S.C. § 103(a). See Br. 5; see above p. 2.
The Primary Examiner’s decision is affirmed.
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No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(1)(iv) (2007).
AFFIRMED

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