Lynch, Michael W. et al.

Patent Trials and Appeals Board

Oct 24, 2019

13725003 - (D) (P.T.A.B. Oct. 24, 2019)

UNITED STATES PATENT AND TRADEMARK OFFICE
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.
13/725,003 12/21/2012 Michael W. Lynch 88-2257A 4107
24114 7590 10/24/2019
LyondellBasell Industries
Legal IP Department
1221 McKinney Street, Suite 700
LyondellBasell Tower
Houston, TX 77010
EXAMINER
BLACKWELL, GWENDOLYN
ART UNIT PAPER NUMBER
1762
NOTIFICATION DATE DELIVERY MODE
10/24/2019 ELECTRONIC
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.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
legal-IP@lyondellbasell.com
PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte MICHAEL W. LYNCH and KENNETH J. KLUG

Appeal 2019-000633
Application 13/725,003
Technology Center 1700
____________

Before ROMULO H. DELMENDO, MARK NAGUMO, and
MICHAEL G. McMANUS, Administrative Patent Judges.

McMANUS, Administrative Patent Judge.

DECISION ON APPEAL

Pursuant to 35 U.S.C. § 134(a), Appellant1 seeks review of the
Examiner’s decision to reject claims 1, 2, 4, 7, 8, 10, and 12. We have
jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM.

1 We use the word “Appellant” to refer to “applicant” as defined in
37 C.F.R. § 1.42 and as listed in the Supplemental Application Data Sheet
filed June 24, 2013. Appellant, Equistar Chemicals LP, is also identified as
the real party in interest. Appeal Br. 2.
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Application 13/725,003

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BACKGROUND

The present application generally relates to a process for preparing
olefin polymers using chromium catalysts. Spec. ¶ 2. The Specification
indicates that “the present invention provides a process for the
polymerization of olefin carried out in the presence of a Cr-oxide supported
catalyst, a co-catalyst, and an effective amount of hydrogen thereby
obtaining an increased catalyst activity.” Id. ¶ 9.
Claims 1 and 12 are illustrative of the subject matter on appeal and are
reproduced below with certain limitations bolded for emphasis:
1. A process for polymerizing an olefin comprising:
(i) forming an activated silica supported hexavalent
chromium catalyst comprising the steps of:
(a) preparing a homogeneous solution comprising an
organic or inorganic chromium compound in a protic
or aprotic polar solvent,
(b) bringing the resulting solution from (a) into contact
with a silica material to form a solid,
(c) removing the solvent from the resulting solid formed
in (b) at a temperature of 20–150 °C for forming a
chromium catalyst precursor, and
(d) calcining the chromium catalyst precursor at a
temperature of 540–800 °C under oxidative
conditions to form the activated silica supported
hexavalent-chromium catalyst; and
(ii) polymerizing an olefin in the presence of:
(a) the silica supported hexavalent-chromium catalyst,
(b) a co-catalyst comprising triethyl boron compound in
an amount corresponding to a boron to chromium
atomic ratio of 1–10, and
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(c) hydrogen at a concentration of 0.03–1.18 mole% and
a pressure of 25–340 psi based upon the total
polymerization contents;
wherein the hexavalent-chromium catalyst has a higher
mileage when the polymerizing step takes place in the
presence of triethyl boron and hydrogen as compared to
the mileage of the hexavalent-chromium catalyst when the
polymerizing step takes place in the absence of triethyl
boron or hydrogen.

12. The process of claim 1, wherein polymerizing of the olefin
is performed in the presence of hydrogen at a concentration
of 0.07-1.5 mole% based upon the total polymerization
contents.
Appeal Br. 10, 11 (Claims App.) (emphasis added).
REJECTIONS
The Examiner maintains the following rejections:
1. Claim 12 is rejected under pre-AIA 35 U.S.C. § 112, 4th
paragraph, as being of improper dependent form for failing to
further limit the subject matter of the claim upon which it
depends, or for failing to include all the limitations of the claim
upon which it depends. Final Act. 3.
2. Claims 1, 2, 4, 7, 8, 10, and 12 are rejected under pre-AIA
35 U.S.C. § 103(a) as being unpatentable over Nooijen et al.
(WO 2010/115614 A1, published October 14, 2010
(“Nooijen”)) and further in view of Schneider et al. (US
2008/0177013 A1, published July 24, 2008 (“Schneider”)). Id.
at 4–8.
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DISCUSSION
Rejection 1. The Examiner rejected claim 12 for improper
dependency. Id. at 3. Claim 12 depends from claim 1 and further requires
that “polymerizing of the olefin is performed in the presence of hydrogen at
a concentration of 0.07-1.5 mole% based upon the total polymerization
contents.” Appeal Br. 11 (Claims App.). The Examiner determines that the
upper limit for the range of hydrogen concentration recited in claim 12 goes
beyond the “0.03–1.18 mole%” stated in claim 1. Final Act. 3; see also 35
U.S.C. § 112, ¶ 4. Appellant does not substantively respond to such
rejection. Accordingly, we summarily affirm. See 37 C.F.R. §
41.37(c)(1)(iv) (2012); Hyatt v. Dudas, 551 F.3d 1307, 1313‒14 (Fed. Cir.
2008); see also Manual of Patent Examining Procedure (MPEP) § 1205.02
(8th ed. July 2010) (“If a ground of rejection stated by the examiner is not
addressed in the appellant’s brief, that ground of rejection will be summarily
sustained by the Board.”).

Rejection 2. The Examiner rejected claims 1, 2, 4, 7, 8, 10, and 12 as
obvious over Nooijen in view of Schneider. Final Act. 4–8. The Appellant
argues the claims as a group. Appeal Br. 4–8. We select claim 1 as
representative, and the remaining claims on appeal will stand or fall with
claim 1 pursuant to 37 C.F.R. § 41.37(c)(1)(iv).
The primary reference, Nooijen, is “directed to a slurry phase
polymerisation process for the preparation of ethylene-α-olefin copolymers
by polymerising ethylene in the presence of a chromium containing catalyst
and a diluent.” Nooijen, Abstract. The Examiner finds that Nooijen teaches
steps (i)(d) and (ii)(a), (b), and (c). Final Act 5.
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The secondary reference, Schneider, is directed toward “[n]ovel
supported, titanized chromium catalysts for the homopolymerization of
ethylene and the copolymerization of ethylene with α-olefins.” Schneider,
Abstract. The Examiner finds that Schneider teaches steps (i)(a), (b), and
(c). Final Act. 6.
The Examiner concedes that “[t]he combination of Nooijen et al. and
Schneider et al. is silent with respect to the chromium catalyst being a
hexavalent-chromium catalyst having a mileage when polymerizing in the
presence of triethylboron and hydrogen higher than the mileage of the
hexavalent-chromium catalyst polymerizing in the absence of triethylboron
or hydrogen.” Final Act. 6. The Examiner determines, however, that one of
ordinary skill in the art would have would have expected the chromium
catalyst of Nooijen and Schneider to be hexavalent and to have a higher
mileage “because Schneider et al. teaches the chromium catalyst is prepared
according to claimed steps (a)-(c), and [Nooijen] activates the chromium
catalyst in dry air [page 10, line 8] and polymerizes ethylene in the presence
of triethylboron and hydrogen as claimed.” Id. at 6–7.
The Examiner additionally determines that the burden is shifted, under
In re Best, 562 F.2d 1252, 1255 (CCPA 1977), to the Applicant to show that
the chromium catalyst of Nooijen and Schneider would not have been
expected to have a mileage higher than one that polymerizes in the absence
of triethylboron or hydrogen. Id. at 7.
Appellant seeks review of this rejection. Appeal Br. 4–8. Appellant
argues that the references relied upon by the Examiner fail to teach the
“hexavalent-chromium catalyst” required by claim 1. Id. at 6. Appellant
points out Schneider’s teaching that “[e]xamples of suitable chromium
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compounds are chromium trioxide and chromium hydroxide and also salts of
trivalent chromium with organic and inorganic acids.” Id. (citing Schneider
¶ 34). Appellant asserts that this portion of Schneider concerns chromium
(III) catalysts rather than chromium (VI) catalysts as required by claim 1.
Id.
Appellant additionally argues that embodiments of the claimed
process display surprising and advantageous benefits. Id. at 7. Appellant
argues that the claimed process yields advantageous catalyst mileage under
hydrogen supplemented conditions. Id.
Appellant further argues that catalyst mileage has not been
demonstrated to be an art-recognized result-effective variable; accordingly,
optimization to obtain the results of the claimed process would not have
been obvious. Id. at 7–8.
In the Answer, the Examiner determines Appellant’s arguments to be
unpersuasive. Answer 8–11. The Examiner finds that the Specification
teaches that “[i]n step a) preference is given to using chromium compound
having a valence of less than six, particularly preferably Cr (III) compounds
. . . . Particular preference is given to salts of acids which during activation
are converted essentially into chromium (VI).” Id. at 8 (citing Spec. ¶ 23)
(emphasis in original). That is, the present Application describes a method
that starts with trivalent chromium compounds and converts the starting
compounds to the hexavalent state. Id. (citing Spec. ¶ 37).
The Examiner finds that Nooijen includes similar teachings. Id. The
Examiner cites to a portion of Nooijen that discloses “a catalyst having a
chromium component on a high titania silica-titania cogel support, obtained
by heat-activation in an oxygen-containing ambient to convert at least a
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portion of any chromium in a lower valent state to the hexavalent state.” Id.
(citing Nooijen at 8:14–17) (emphasis in original). The Examiner further
finds that Schneider teaches to “calcine[] the precatalyst comprising the
trivalent chromium compound at 500°C to 800°C in an oxygen-containing
atmosphere.” Answer 8 (citing Schneider ¶ 14). The Examiner concludes
that since Schneider heats the trivalent chromium compounds in an oxygen-
containing atmosphere to a temperature within the claimed range, the
chromium catalyst of Schneider would be expected to be converted to the
hexavalent state. Id. at 8–9.
Appellant did not file a Reply Brief.
We find the Examiner’s reasoning to be persuasive. Both Schneider
and the Specification teach to use trivalent chromium in chromium catalyst
preparation. See Spec. ¶ 23; Schneider ¶ 34. Further, Schneider teaches
similar process steps including heating under oxidizing conditions. See
Schneider ¶¶ 33–39; Answer 8–9. Appellant has not shown error in the
Examiner’s reasoning that the hypothetical combined process would have
resulted in a hexavalent-chromium catalyst.
The Examiner further finds that Appellant has failed to show that the
claimed process exhibits unexpected benefits relative to the prior on several
bases. Id. at 9–11. In its Appeal Brief, Appellant specifically discusses
Examples 16–20 of Table 3 of the Specification and Examples 21–25.
Appeal Br. 7. As found by the Examiner, Examples 16–20 lack triethyl
boron (TEB) and, thus, fall outside the claims. Answer 10; Spec., Table 3.
Examples 21–25 include triethyl boron co-catalyst, but exhibit catalytic
activity lower than shown in a prior example lacking triethyl boron but
employing a comparable hydrogen pressure. Spec., Table 3 (compare
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Example 4 with Example 23); see also id. ¶ 51. Nor has Appellant shown
that the cited test results are commensurate in scope with the claims (e.g.,
Appellant has not cited to test results showing hydrogen pressure greater
than 340 psi). See In re Peterson, 315 F.3d 1325, 1329 (Fed. Cir. 2003)
(“the applicant's showing must be commensurate in scope with the claimed
range”).
Accordingly, Appellant has failed to show that the use of both triethyl
boron and the recited hydrogen pressure leads to greater polymerization
activity. For at least this reason, we find Appellant’s arguments regarding
surprising and advantageous benefits to be unpersuasive.
In regard to Appellant’s argument that “optimization to obtain the
results of the claimed process would not have been within the grasp of one
of ordinary skill in the art.” Appeal Br. 7–8. We adopt the Examiner’s
determination that “the Office action never set forth that catalyst mileage
was an art recognized, result-effective variable that could be optimized.
Appellants are arguing against a position that was not made in the Office
action.” Answer 10–11.
Accordingly, Appellant has not shown error in the rejection.

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CONCLUSION

In summary:
Claims
Rejected
Basis  Affirmed Reversed
12 § 112, ¶ 4  12
1, 2, 4, 7, 8, 10,
and 12
§ 103(a), Nooijen in
view of Schneider 
1, 2, 4, 7, 8,
10, and 12

Overall Outcome 1, 2, 4, 7, 8,
10, and 12

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