Ex Parte Thetford et al

Board of Patent Appeals and Interferences

Apr 30, 2010

10505840 (B.P.A.I. Apr. 30, 2010)

UNITED STATES PATENT AND TRADEMARK OFFICE
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BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
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Ex parte DEAN THETFORD,
JOHN DAVID SCHOFIELD, and NEIL LOUIS SIMPSON
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Appeal 2009-004593
Application 10/505,840
Technology Center 1700
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Decided: April 30, 2010
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Before CHUNG K. PAK, CHARLES F. WARREN, and
MARK NAGUMO, Administrative Patent Judges.

NAGUMO, Administrative Patent Judge.

DECISION ON APPEAL

Appeal 2009-004593
Application 10/505,840

A. Introduction1
Dean Thetford, John David Schofield, and Neil Louis Simpson
(“Thetford”) timely appeal under 35 U.S.C. § 134(a) from the final
rejection2 of claims 1-6, 9-12, and 14-22. We have jurisdiction under
35 U.S.C. § 6. We AFFIRM.
The subject matter on appeal relates to phosphate ester dispersants
prepared by the reaction of excess phosphating agent and an alcohol.
The 840 Specification explains that the excess is at least 1.3:1 on a molar
basis of phosphorus to alcohol. (Spec. 1, 2d para.) The dispersants are said
to provide superior properties such as lower millbase viscosity, higher
pigment loading, superior flocculation resistance, and better stability of
millbases, paints, and ink. (Id. at 1, 3d para.) Paints containing the
dispersants are said often to exhibit superior gloss, haze, and color strength,
and, in the case of transparent iron oxides, higher transparency. (Id.)

1 Application 10/505,840, Phosphate Esters Dispersants, filed 26 August
2004 as the national stage of an international application filed 18 February
2003, claiming the benefit under 35 U.S.C. § 119(a) of an application filed
in the United Kingdom on 28 February 2002. The specification is referred
to as the “840 Specification,” and is cited as “Spec.” The real party in
interest is listed as The Lubrizol Corporation. (Appeal Brief, filed 10 June
2008 (“Br.”), 2.)
2 Office action mailed 24 July 2007 (“Final Rejection”; cited as “FR”).
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Application 10/505,840

Representative Claim 1 is reproduced from the Claims Appendix to
the Principal Brief on Appeal:
1. A dispersant which comprises
the reaction product of a phosphating agent and a
compound of formula 1
R-OH 1
wherein the ratio of each atom of phosphorus in the
phosphating agent to the compound of formula 1 is not
less than 1.3:1,
including mixtures and salts thereof; and wherein
R is a residue of a polyester and/or polyether
having a polymerisation terminating group
wherein the compound of formula 1 is a compound of
formula 2
TO - (CO - A -O)n (BO)mH 2
wherein
T is a polymerisation terminating group selected
from C1-36 alkyl that can be linear or branched;
A is C1-30-alkylene or C2-30-alkenylene;
B is C2-6-alkylene;
n and m are each, independently, from 0 to 500;
and n + m is not less than 4;
including salts and mixtures thereof;
with the proviso that if n is zero, then T is selected
from a C1-4 alkyl that can be linear or branched.
(Claims App., Br. 12; paragraphing and indentation added.)
Preferred phosphating agents are POCl3, P2O5, and polyphosphoric
acid. (Spec. 6, last para.) The preferred alcohols are polyester-polyether
monoalcohols. The ester groups (containing A) are said to be preferred for
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Appeal 2009-004593
Application 10/505,840

polar solvents, including water. (Id. at 5, paras. 3-4.) The ether groups
(containing B) are said to be preferred for nonpolar solvents. (Id. at 6,
1st full para.) In the words of the 840 Specification, “[i]n all cases the
dispersant can be a mixture of mono-, di- and tri-phosphate.” (Spec. 1,
2d para.)
The Examiner has maintained the following grounds of rejection:3
A. Claims 1-6, 9-12, and 14-22 stand rejected under
35 U.S.C. § 103(a) in view of the teachings of
Haubennestel.4
B. Claims 1-6, 14, 15, 17-19, and 22 stand rejected
under 35 U.S.C. § 103(a) in view of the teachings of
Waag.5
Thetford contends the Examiner erred because “[t]he text and
examples of Haubennestel et al. do not teach or motivate one to use any
molar excess of P relative to the OH of the alcohol.” (Br. 9, 2d para.)
Similarly, according to Thetford, Waag “teaches away from phosphating
with molar ratio of not less than 1.3:1 P to OH” as recited in the rejected
claims. (Br. 11, first para.) Thetford does not raise substantively separate
arguments for any of the dependent claims.
The disposition of this case hinges on the proper construction of
claim 1, which covers a dispersant comprising the reaction product of a

3 Examiner’s Answer mailed 3 September 2008. (“Ans.”)
4 Karl-Heinz Haubennestel and Wolfgang Pritschins, Phosphoric Acid
Esters, Method of Producing Them, and Use Thereof as Dispersants, U.S.
Patent 5,151,218 (1992).
5 Ake Waag, Process for Preparing Spray Dried Detergent Compositions,
U.S. Patent 3,741,913 (1973).
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Appeal 2009-004593
Application 10/505,840

phosphating agent and an alcohol, conducted in the presence of at least
a 1.3:1 molar excess of phosphorus to alcohol.
B. Discussion
Findings of fact throughout this Opinion are supported by a
preponderance of the evidence of record.
During prosecution, “the PTO applies to the verbiage of the proposed
claims the broadest reasonable meaning of the words in their ordinary usage
as they would be understood by one of ordinary skill in the art, taking into
account whatever enlightenment by way of definitions or otherwise that may
be afforded by the written description contained in the applicant’s
specification.” In re Morris, 127 F.3d 1048, 1054 (Fed. Cir. 1997). In
particular, the transitional term “comprising” is a well-established term of art
in patent law that leaves the claim open to additional, unrecited elements or
steps. See, e.g., In re Baxter, 656 F.2d 679, 686 (CCPA 1981) (“as long as
one of the monomers in the reaction is propylene, any other monomer may
be present, because the term ‘comprising’ permits the inclusion of other
steps, elements, or materials.”)
In the present case, Thetford has not raised any substantial argument
for patentability of any of the appealed dependent claims. Thus, all claims
stand or fall with claim 1. 37 C.F.R. § 41.37(c)(1)(vii).
Claim 1 covers a dispersant comprising the reaction product of a
phosphating agent with an alcohol, where the phosphating agent is present,
on a molar basis, of 1.3 atoms of phosphorus per alcohol molecule. As
shown in formulas 1 and 2, the alcohol has a single hydroxyl (-OH) group.
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Application 10/505,840

According to the 840 Specification, “[i]n all cases the dispersant can be a
mixture of mono-, di- and tri-phosphate.” (Spec. 1, 2d para.) That is, based
on the fundamental phosphating agent, phosphoric acid, H3PO4 ((HO)3P=O),
each hydrogen may be replaced, formally, by an R group from the alcohol,
R-OH. The “comprising” transitional language leaves the claimed
dispersant open to other components, including pigments, fillers, but also
other dispersants, including other phosphoric acid ether-esters, no matter
how they are made. Thus, although claim 1 requires that any single
reference disclose a dispersant that contains products necessarily produced
by the reaction of a phosphating agent and an alcohol within the scope of
formula 2, there is no language in claim 1 that excludes the presence of other
phosphorus-containing dispersants. Therefore, claim 1 cannot be said to
limit the distribution of products of the reaction by excluding more of a
particular mono-, di-, or tri-ester than might be possibly obtained by the
reaction of a molar excess of at least 1.3 phosphating agent6 with an alcohol
of formula 2.
With this understanding of the claimed subject matter, we find that
Haubennestel describes phosphoric acid esters and their salts said to be
useful for facilitating the dispersal of solids in paints. (Haubennestel, col. 1,
ll. 11-14.) The mono- and di-esters covered by Haubennestel Formula (I),
(OH)3-n(P=O)(OR)n, with n = 1 or 2 (id. at col. 2, ll. 33-39), where R
represents the residue of an oxalkylated monoalcohol (particularly a C1-C4
monoalcohol) containing carboxylic acid ester groups (id. at col. 3, ll. 7-16),
have the same composition and the same molecular weight (Mn of ROH

6 Throughout this Opinion, all excesses are based on phosphorus to alcohol.
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Application 10/505,840

ranges from 200 to 10,000, particularly preferably from 400 to 2000 (id.
at col. 3, ll. 42-44)) as those preferred by Thetford (cf. Spec. 2, 2d full para.,
disclosing the same outer limits and similar preferred ranges). Thus,
Haubennestel describes ester dispersants that encompass the phosphoric acid
esters and salts described in the 840 Specification. While the weight of the
evidence supports Thetford’s arguments that Haubennestel does not
contemplate a 1.3 molar or greater excess of phosphating agent as recited in
claim 1, we cannot say that the claims exclude compositions disclosed or
obvious in view of Haubennestel. Thus, for example, di-ester in dispersants
made following the disclosure of Haubennestel that are in excess of what
might be produced by the reaction of 1.3 equivalents of phosphating agent
per 1 mole of alcohol ROH are not excluded, e.g., by recitation of property
limitations or by express exclusion of other phosphate esters in claim 1.
Similarly, Waag discloses phosphate esters said to be useful as
dispersants in detergent compositions that are to be spray dried. (Waag,
col. 1, ll. 15-25.) In particular, Waag describes phosphate esters
(R1O)(R2O)(OH)(P=O), where R1 and R2 represent hydrogen or a group
R(OC2H4). (Id. at col. 2, ll. 50-60.) R is said to represent “a saturated . . .
straight or branched alkyl . . . radical having a total of 4-22 . . . carbon atoms
in the alkyl . . . portion.” (Waag, col. 2, ll. 56-60.) These phosphate esters
are within the compositional range required by claim 1, formula 2, where
n = 0 (i.e., no carboxylic acid esters present). Again, although the weight of
the evidence supports Thetford’s arguments regarding the preferred ratios of
phosphating agent to alcohol, there are no claim limitations in claim 1 that
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Application 10/505,840

exclude the “excess” esters, if any, present in dispersants prepared following
Waag.
We conclude that the errors, such as they may be, in the Examiner’s
analysis of Haubennestel and of Waag, are harmless because the claims,
properly understood, do not exclude the phosphate ester dispersant
compositions disclosed or obvious in view of either reference. In a similar
situation, our reviewing court explained that it would
decline to attempt to harmonize the applicants’ interpretation
with the application and prior art. Such an approach puts the
burden in the wrong place. It is the applicants’ burden to
precisely define the invention, not the PTO's. See 35 U.S.C.
§ 112 ¶ 2 (“The specification shall conclude with one or
more claims particularly pointing out and distinctly claiming
the subject matter which the applicant regards as his
invention.”).
Morris, 127 F.3d at 1056. We shall do the same here, bearing in mind that
Thetford may attempt to amend the claims in an appropriate continuing
application.
D. Order
We AFFIRM the rejection of claims 1-6, 9-12, and 14-22 under
35 U.S.C. § 103(a) in view of the teachings of Haubennestel.
We AFFIRM the rejection of claims 1-6, 14, 15, 17-18, and 22 under
35 U.S.C. § 103(a) in view of the teachings of Waag.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).
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Appeal 2009-004593
Application 10/505,840

AFFIRMED

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SAMUEL B LAFERTY
THE LUBRIZOL CORPORATION
PATENT DEPT. MAIL DROP 022B
29400 LAKELAND BOULEVARD
WICKLIFFE, OH 44092-2298
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