Ex Parte 5376159 et al

Board of Patent Appeals and Interferences

Jan 26, 2009

90006755 (B.P.A.I. Jan. 26, 2009)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte NALCO COMPANY
____________

Appeal 2008-5898
Reexamination Control 90/006,755
Patent 5,376,159
Technology Center 1700
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Decided: January 26, 2009
____________

Before CAROL A. SPIEGEL, ROMULO H. DELMENDO, and
MICHAEL P. COLAIANNI, Administrative Patent Judges.

DELMENDO, Administrative Patent Judge.

DECISION ON APPEAL
Nalco Company (Patent Owner and Appellant) appeals under 35
U.S.C. §§ 134(b) and 306 from a final rejection of claims 1, 2, and 4-12
(Appeal Brief filed January 8, 2008, hereinafter “Br.”; Final Office Action
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mailed December 8, 2005).1 We have jurisdiction under 35 U.S.C.
§§ 134(b) and 306.
We AFFIRM.

STATEMENT OF THE CASE
This reexamination proceeding arose from a request for ex parte
reexamination filed by a third party, Bruce E. Peacock, Esq., of Wegman,
Hessler and Vanderburg of Cleveland, Ohio, on August 20, 2003 of United
States Patent 5,376,159 (hereinafter ‘159 Patent) entitled “CORROSION
INHIBITOR FOR NITROGEN FERTILIZER SOLUTIONS” and issued to
Raymond T. Cunningham and Kristen T. Moore on December 27, 1994,
based on Application 08/119,960 filed on September 10, 1993 (Request for
Ex Parte Reexamination filed August 20, 2003).
The invention of the ‘159 Patent relates to a method for inhibiting
corrosion of ferrous metal surfaces by nitrogen fertilizer solutions in contact
therewith (col. 2, ll. 13-16).
Claim 1, which is illustrative of the subject matter on appeal, reads as
follows:
1. In a method for inhibiting corrosion of ferrous metal
surfaces by nitrogen fertilizer solutions in contact therewith,
including the steps of blending a corrosion inhibitor with a
fertilizer solution consisting essentially of urea, ammonium
nitrate and a minor amount of water, and contacting the metal

1 Nalco Company is said to be the real party in interest as evidenced
by the Assignment Document recorded on March 14, 2006 at Reel 017297,
Frame 0730 (Br. 2).

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surfaces with the resulting blend, the improvement consisting
of:
using an effective, soluble amount less than 200 ppm, by
weight of the fertilizer solution, of an alkali metal molybdate as
the corrosion inhibitor in the blending step, wherein the
fertilizer solution contains from about 20 to about 50 percent by
weight water and has a pH from about 7 to about 8.
(Br. 8, Claims Appendix, underlining omitted.)

The Examiner relied upon the following as evidence of
unpatentability:
Langguth 3,024,100 Mar. 6, 1962
Ulmer CA 865038 Mar. 2, 1971
O. Hollander and G.E. Geiger, Development of a Corrosion Inhibitor for
Low Carbon Steel in Concentrated Solutions of Urea-Ammonium Nitrate
Fertilizers, National Association of Corrosion Engineers: Corrosion 88, St.
Louis, MO, Paper No. 347 (March 21-25, 1988) (hereinafter “Hollander”).
The Examiner rejected claims 1, 2, and 4-12 under 35 U.S.C. § 103(a)
as unpatentable over Hollander alone or Hollander taken with either or both
of Ulmer and Langguth (Examiner’s Answer mailed June 26, 2006,
hereinafter “Ans.,” 3-5).2
The Examiner found that Hollander describes the use of less than 25
ppm of sodium molybdate as a corrosion inhibitor for a UAN (urea-
ammonium nitrate) fertilizer (Ans. 3-4). The Examiner determined that
while Hollander does not explicitly disclose the pH or the water content of
the fertilizer solution, a person having ordinary skill in the art would have
found it obvious to arrive at the claimed pH and water contents (Ans. 4).

2 The Examiner indicated that claim 3 has been canceled and that the
rejection under 35 U.S.C. § 102(b) of claims 1, 2, 4, and 6 over Hollander
has been withdrawn (Ans. 3).
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Appellant’s only contention in this appeal is that Hollander teaches
away from the claimed invention because the reference states that
“molybdate is a ‘poor’ corrosion inhibitor for UAN solutions” (Br. 6).
Appellant therefore believes that it has “rebutted a prima facie case of
obviousness by showing that the prior art teaches away from the claimed
invention” (id.).

ISSUE
Thus, the sole issue arising from the contentions of the Examiner and
Appellant is:
Has Appellant shown reversible error in the Examiner’s rejection by
demonstrating that Hollander teaches away from the claimed invention?

FINDINGS OF FACT
1. The ‘159 Patent states that UAN solutions are commercially
popular fertilizer solutions produced by blending urea solution,
ammonium nitrate solution, and any additional water in a
mixing tank and that it can be made with as little as 20% by
weight water, but more typically 30-40% by weight (col. 1, ll.
12-27).
2. Hollander explains the inhibition of corrosion by fertilizer
solutions as follows (Hollander 1, ¶1):
Low carbon steel (LCS) exposed to concentrated
solutions of urea-ammonium nitrate (UAN) can develop
either a fully or partially passive film. The integrity of
the film phase that develops depends primarily on pH
and, to a lesser extent, on nitrate ion concentration. Urea
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interacts synergistically with nitrate in the presence of
low-carbon steel; surface adsorption may be the
mechanism leading to higher true current densities.
Based on this information, an inhibitor was developed
that protects the naturally formed passive film from pH
depressions.
3. Hollander confirms that UAN solutions are blends of
ammonium nitrate and urea (Hollander 1, ¶2).
4. Hollander further teaches that UAN solutions are “typically
produced at 80% solids (32% N) and 70% solids (28% N)[]”
(Hollander 1, ¶2).
5. According to Hollander, UAN solutions “are pH adjusted with
ammonia and then held in storage tanks,” which are made of
low carbon steel (LCS) (Hollander 1, ¶¶2 and 3).
6. Hollander describes the addition of 25 mg/L of sodium
molybdate as a corrosion inhibitor to 32% nitrogen fertilizer
solution prepared by adding reagent-grade ammonium nitrate
and urea to deionized water, the pH of which was “adjusted to
an initial value of 5.5 to 6.0 to ensure a corrosive
environment[]” appropriate for the corrosion inhibition test
(Hollander 8-9; Table III).
7. Hollander reports that sodium molybdate inhibited corrosion by
5% (Table III).
8. Hollander teaches that, relative to organic phosphates and
sulfonates, molybdate was a “poor” inhibitor (Hollander 9, third
full paragraph).
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9. Hollander further teaches that “[l]ow carbon steel (LCS)
naturally passivates in UAN fertilizer solutions as long as the
pH is above 6[]” (Hollander 10, ¶3).

PRINCIPLES OF LAW
On appeal to this Board, Appellant must show that the Examiner
reversibly erred in finally rejecting the claims. Cf. In re Kahn, 441 F.3d 977,
985-986 (Fed. Cir. 2006); see also 37 C.F.R. § 41.37(c)(1)(vii).
“Section 103 forbids issuance of a patent when ‘the differences
between the subject matter sought to be patented and the prior art are such
that the subject matter as a whole would have been obvious at the time the
invention was made to a person having ordinary skill in the art to which said
subject matter pertains.’” KSR Int’l Co. v. Teleflex, Inc., 127 S. Ct. 1727,
1734 (2007).
In re Gurley, 27 F.3d 551, 553 (Fed. Cir. 1994), provided guidance on
“teaching away” as follows:
Gurley's position appears to be that a reference that
“teaches away” cannot serve to create a prima facie case of
obviousness. We agree that this is a useful general rule.
However, such a rule can not be adopted in the abstract, for it
may not be applicable in all factual circumstances. Although a
reference that “teaches away” is a significant factor to be
considered in determining unobviousness, the nature of the
teaching is highly relevant, and must be weighed in substance.
A known or obvious composition does not become patentable
simply because it has been described as somewhat inferior to
some other product for the same use.
The facts in Gurley's record are that this use of epoxy
was known, the structure of these circuit boards was known,
and epoxy had been used for Gurley's purpose. We share
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Gurley's view that a person seeking to improve the art of
flexible circuit boards, on learning from Yamaguchi that epoxy
was inferior to polyester-imide resins, might well be led to
search beyond epoxy for improved products. However,
Yamaguchi also teaches that epoxy is usable and has been used
for Gurley's purpose. The Board recognized Yamaguchi's
teaching of the deficiencies of epoxy-impregnated material, but
observed that Gurley did not distinguish his epoxy product from
the product described by Yamaguchi. On the facts of this case,
Gurley's “teaching away” argument was insufficient to establish
patentability. Gurley did not offer specific epoxies, or
improved properties, and we are not presented with the question
of whether any such products might meet the requirements of
patentability. Even reading Yamaguchi's description as
discouraging use of epoxy for this purpose, Gurley asserted no
discovery beyond what was known to the art.
Thus, “case law does not require that a particular combination must be
the preferred, or the most desirable, combination described in the prior art in
order to provide the motivation for the current invention.” In re Fulton, 391
F.3d 1195, 1200 (Fed. Cir. 2004). Rather, the court has instructed:
“[T]he question is whether there is something in the prior art as
a whole to suggest the desirability, and thus the obviousness, of
making the combination,” not whether there is something in the
prior art as a whole to suggest that the combination is the most
desirable combination available.
Id. (quoting In re Beattie, 974 F.2d 1309, 1311 (Fed. Cir. 1992)).

ANALYSIS
Appellant has relied on the same argument for all the appealed claims
(Br. 5-6). We therefore select claim 1 as representative and confine our
discussion to this selected claim. See 37 C.F.R. § 41.37(c)(1)(vii).
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Appellant does not dispute the Examiner’s determination that
Hollander would have at least suggested to one of ordinary skill in the art the
blending of an appropriate amount of a corrosion inhibitor with a UAN
fertilizer solution having a pH and water content as recited in claim 1 (Facts
1-6 and 9; Ans. 3-4). Rather, it is Appellant’s position that Hollander
teaches away from using sodium molybdate as a corrosion inhibitor in view
of Hollander’s disclosure at page 9, third full paragraph (Br. 6; Fact 8).
We disagree. In a working example, Hollander explicitly describes
the blending of 25 mg/L of sodium molybdate as a corrosion inhibitor with
UAN fertilizer solution (Fact 6). While Hollander reports that sodium
molybdate provided 5% corrosion inhibition and that this degree of
inhibition was “poor” relative to some of the other tested compounds, a
person having ordinary skill in the art would nevertheless have understood
that sodium molybdate does inhibit corrosion to some extent (Facts 7 and 8).
As succinctly pointed out by the Examiner, “the claims do not require any
level beyond [i.e., above]” 5% corrosion inhibition and “are so broad that
they encompass ‘poor’ corrosion inhibitors” (Ans. 5). Contrary to
Appellant’s belief, Hollander’s teaching would not have suggested to one of
ordinary skill in the art that sodium molybdate would be inoperable as to
teach away from the claimed invention, but rather it would have led a person
having ordinary skill in the art to reasonably expect that sodium molybdate
is an effective, albeit less preferred, corrosion inhibitor. See Fulton, 391
F.3d at 1200.

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CONCLUSION
On this record, Appellant has failed to demonstrate reversible error in
the Examiner’s determination that Hollander would not have taught away
from the claimed invention.

DECISION
The Examiner’s decision to reject appealed claims 1, 2, and 4-12 is
affirmed.
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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MAT

Robert A. Miller
Patent & Licensing Department
NALCO CHEMICAL COMPANY
One Nalco Center
Naperville IL 60563-1198

CC: Third Party Requester:

Bruce E. Peacock, Esq.
Wegman, Hessler & Vanderburg
6055 Rockside Rd Suite 200
Cleveland OH 44131