Ex Parte El Shaari et al

Patent Trial and Appeal Board

Dec 17, 2013

11729672 (P.T.A.B. Dec. 17, 2013)

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.
11/729,672 03/29/2007 Nabil A. El Shaari 020569-13801
(P206-1522-U
6424
71762 7590 12/17/2013
JONES & SMITH , LLP
2777 ALLEN PARKWAY
SUITE 1000
HOUSTON, TX 77019
EXAMINER
BLAND, ALICIA
ART UNIT PAPER NUMBER
1768
MAIL DATE DELIVERY MODE
12/17/2013 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 PATENT TRIAL AND APPEAL BOARD
____________

Ex parte NABIL A. EL SHAARI
and JEFFREY C. DAWSON
____________

Appeal 2012-009787
Application 11/729,672
Technology Center 1700
____________

Before EDWARD C. KIMLIN, PETER F. KRATZ, and
LINDA M. GAUDETTE, Administrative Patent Judges.

KIMLIN, Administrative Patent Judge.

DECISION ON APPEAL

This is an appeal from the final rejection of claims 2-14 and 17-31.
We have jurisdiction under 35 U.S.C. § 6(b). Claim 17 is illustrative:
17. A method of enhancing the productivity of a hydrocarbon-
bearing formation comprising:

(a) hydrating a guar derivative in an aqueous alcohol solution
wherein the amount of alcohol in the aqueous alcohol is between from about
5 to about 40 volume percent;

(b) introducing a borate crosslinking agent to the product of step (1)
to generate a viscous fluid;
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Application 11/729,672

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(c) introducing into the viscous fluid an enzyme and an organic acid
ester to render a pumpable well treatment fluid;

(d) introducing the pumpable well treatment fluid into the
hydrocarbon-bearing formation wherein the amount of the aqueous alcohol
in the pumpable well treatment fluid is between from about 95 to about 98
weight percent;

(e) increasing the activity of the enzyme by decreasing the pH of the
well treatment fluid in-situ by hydrolyzing the organic acid ester; and

(f) degrading the hydrated guar derivative in the aqueous alcohol with
the enzyme.

The Examiner relies upon the following references as evidence of
obviousness:
Dawson et al. (Dawson) 6,793,018 B2 Sep. 21, 2004
Qu et al. (Qu) US 2003/0019627 A1 Jan. 30, 2003
Gupta et al. (Gupta) US 2004/0072700 A1 Apr. 15, 2004
Dusterhoft et al. (Dusterhoft) US 2008/0210424 A1 Sep. 4, 2008

Appellants' claimed invention is directed to a method of enhancing the
productivity of a hydrocarbon-bearing formation. The method entails
hydrating a guar derivative in an aqueous alcohol solution, introducing a
borate crosslinking agent to generate a viscous fluid, introducing an enzyme
and an organic acid ester into the viscous fluid to render it pumpable,
introducing the treatment fluid into a hydrocarbon-bearing formation,
increasing the activity of the enzyme by decreasing the pH of the fluid in
situ by hydrolyzing the organic acid ester, and degrading the hydrated guar
derivatives with the enzyme.
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Application 11/729,672

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Appealed claims 2-14 and 17-31 stand rejected under 35 U.S.C.
§103(a) as being unpatentable over Dawson in view of Gupta and Qu.
Claims 2-14 and 17-31 also stand rejected under 35 U.S.C. §103(a) as being
unpatentable over Gupta in view of Dawson and Dusterhoft.
We have thoroughly reviewed each of Appellants' arguments for
patentability, as well as the declaration evidence relied upon in support
thereof. However, we are in complete agreement with the Examiner that the
claimed subject matter would have been obvious to one of ordinary skill in
the art within the meaning of §103 in view of the applied prior art.
Accordingly, we will sustain the Examiner's rejections for the reasons set
forth in the Answer, which we incorporate herein, and we add the following
for emphasis only.1
There is no dispute that Dawson, like Appellants, discloses a
fracturing fluid comprising an aqueous solvent, a hydratable guar derivative,
a borate crosslinking agent, an enzymatic breaking agent such as cellulose,
and an ester that may be formed by reaction with oxalic, succinic, citric
acids, and the like. As appreciated by the Examiner, although Dawson
discloses that the aqueous solvent may include other neutral solvents, the
reference does not expressly disclose that the mutual solvent may be an
alcohol. However, Qu evidences that alcohols, such as methanol, ethanol,
and isopropanol, may be used as a mutual solvent in a fracturing fluid.
Furthermore, as set forth by the Examiner, Gupta discloses fracturing fluids
comprising an aqueous alcohol as a solvent, along with a hydratable

1 We agree with Appellants that Dusterhoft is not prior art, but the reference
is not necessary to support the Examiner's conclusion of obviousness.
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Application 11/729,672

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polymer, a crosslinking agent, and a breaking agent. Accordingly, based on
the collective teachings of the applied prior art, we fully concur with the
Examiner that it would have been obvious for one of ordinary skill in the art
to select an alcohol, such as methanol, as the mutual solvent in the fracturing
fluid of Dawson.
The principal argument advanced by Appellants is that a mutual
solvent is not used to hydrate a polymer, and the alcohol in Gupta is not used
as a mutual solvent. However, Qu clearly teaches that alcohols, such as
methanol, may be used as a mutual solvent in a fracturing fluid of the type
disclosed by Dawson. Consequently, whether or not Gupta uses an alcohol
as a mutual solvent, it would have been obvious for one of ordinary skill in
the art to select an alcohol as the mutual solvent or as a water compatible co-
solvent for use as part of the water-containing solvent of Dawson.
Moreover, inasmuch as Gupta teaches that a combination of water and
alcohol can be used as a solvent in a fracturing fluid comprising a guar
derivative, we are convinced it would have been obvious for one of ordinary
skill in the art to incorporate an alcohol as a co-solvent in the fluid of
Dawson whether or not it is characterized as a mutual solvent.
Appellants rely upon the Qu Affidavit for evidence that mutual
solvents are not used to hydrate galactomannans, but are present in fluids in
order to reduce surface tension and to enhance recovery. However, the
affiant does not state that an alcohol such as methanol is not a mutual
solvent. The affiant states "[a] mutual solvent is commonly not a preferred
solvent to hydrate a polymer" (para. 14, emphasis added). Hence, while an
alcohol may not be a preferred mutual solvent to hydrate a polymer, the
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affidavit is not evidence that an alcohol cannot function as a mutual solvent
for hydrating a polymer. Nor is the affidavit evidence sufficient to establish
that it would have been nonobvious for one of ordinary skill in the art to use
an alcohol as a co-solvent in a fracturing fluid of the type disclosed by
Dawson. Indeed, to so state would contradict the disclosure in Qu's patent
cited above.
Also, although the affidavit states that "Gupta uses the alcohol for a
different purpose than as a mutual solvent" (para. 15), it is not necessary for
a finding of obviousness that one of ordinary skill in the art incorporate an
alcohol in the fracturing fluid of Dawson as a mutual solvent. Although Qu
evidences that it would have been obvious for one of ordinary skill in the art
to select an alcohol as the mutual solvent of Dawson, it would also have
been obvious for one of ordinary skill in the art to use an alcohol as a co-
solvent in an aqueous system of Dawson even without the added teachings
of Qu.
Concerning the rejection of all the appealed claims over Gupta in
view of Dawson, it follows from the above discussion that we agree with the
Examiner that the claimed subject matter would have been obvious to one of
ordinary skill in the art based on the collective teachings of Gupta and
Dawson.
In conclusion, based on the foregoing and the reasons well stated by
the Examiner, the Examiner’s decision rejecting the appealed claims is
affirmed.

Appeal 2012-009787
Application 11/729,672

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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).
AFFIRMED

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