Ex Parte Phillips et al

Patent Trial and Appeal Board

Oct 24, 2012

11323662 (P.T.A.B. Oct. 24, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
__________

Ex parte NOLAN LEE PHILLIPS, DUEN-WU HUA,
WILLIAM C. FULTZ, and PATRICK DONALD McGILL
__________

Appeal 2011-010731
Application 11/323,662
Technology Center 1600
__________

Before TONI R. SCHEINER, FRANCISCO C. PRATS, and
STEPHEN WALSH, Administrative Patent Judges.

SCHEINER, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 from the final rejection of
claims 1-7, directed to a dentifrice. The claims have been rejected as
obvious. We have jurisdiction under 35 U.S.C. § 6(b).
We affirm.
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STATEMENT OF THE CASE
Claims 1-7 are pending and on appeal. The claims have not been
argued separately and therefore stand or fall together. 37 C.F.R. §
41.37(c)(1)(iv). Claims 1-3 are representative:
1. A dentifrice comprising an amorphous rice hull silica abrasive
and optionally including any other dental abrasive component, wherein said
dentifrice exhibits a radioactive dentin abrasion value of from 96 to 138 and
a pellicle cleaning ratio to radioactive dentin abrasion (PCR:RDA) ratio of
from 0.5 to 0.95, wherein said amorphous rice hull silica abrasive is present
in an amount of from 10% to 35% by weight therein, and wherein said
amorphous rice hull silica abrasive has a median particle size of from 4 to 48
microns and an Einlehner Abrasion value of from 20.29 to 40.5 mg loss.
2. The dentifrice of Claim 1 wherein another dental abrasive
component is present.
3. The dentifrice of Claim 2 wherein said other dental abrasive
component is selected from precipitated silica, silica gels, precipitated
calcium carbonate, ground calcium carbonate, chalk, magnesium carbonate,
dicalcium phosphate and its dihydrate forms, calcium pyrophosphate,
zirconium silicate, potassium metaphosphate, magnesium orthophosphate,
tricalcium phosphate, perlite, and any mixtures thereof.
Claims 1-7 stand rejected under 35 U.S.C. § 103(a) as unpatentable
over White, Jr.
1
and International Silica technologies.
2

FINDINGS OF FACT
1. White Jr. discloses dentifrice compositions comprising an
orally acceptable carrier and a precipitated silica, which may be “used alone
or in combination with other abrasives preferably relatively softer silica
abrasives” (White Jr. ¶¶ 8-12).

1
White, Jr. et al., US 2003/0039617 A1, published February 27, 2003.
2
International Silica Technologies, www.dakram.com/09-StratoSil-
Website-Home-Page-5-19-04.pdf.2004.

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2. White Jr. discloses that “[t]he precipitated silicas of the
invention are . . . synthetic hydrated amorphous silicas” (White Jr. ¶ 32), and
are “characterized by having a 10% Brass Einlehner Abrasion [BEA] value[]
ranging from greater than about 7, preferably from about 10 to about 19 and
having a mean value (MV) particle size in the range of about 8 to about 14
[microns]” (id. at ¶ 27). White Jr. also discloses that “[t]he silicas preferably
possess a 10% BEA value of greater than about 7, preferably greater than
about 10 and preferably between about 15 and about 40” (id. at ¶ 40). “The
total abrasive in the compositions . . . is present at a level of from about 6%
to about 70%, preferably from about 15% to about 35% when the dentifrice
is a toothpaste” (id. at ¶ 51).
3. White Jr. further discloses that “[t]he Pellicle Cleaning Ratio
(PCR) of the precipitated silica of the invention, which is a measure of the
cleaning characteristics of a dentifrice, ranges from about 70 to about 140
and preferably from about 105 to about 125” (White Jr. ¶ 29), while “[t]he
Radioactive Dentin Abrasion (RDA) of the inventive silicas, which is a
measure of the abrasiveness of the precipitated silicas . . . when incorporated
into a dentifrice is less than about 250, preferably ranging from about 100 to
about 225, more preferably from about 150 to about 200” (White Jr. ¶ 30).
4. According to White Jr.:
The effects of mixtures of abrasives are particularly
noteworthy. Most specifically, it is shown that the addition of
the Zeodent 109 silica as a 50% mixture with softer silicas
produces polishing effects comparable to those achieved with
the harder silica at doses comparable to the combined mixture
dosage as illustrated herein. These improved polishing
characteristics can be achieved with only partial substitution of
the present unique silica with hardness values above BEA of 7,
preferably above BEA of 10.
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Importantly, the abrasive systems using the present silica
with elevated abrasion and hardness characteristics by itself or
in combination with prior art softer silicas result not only in
increased enamel polishing but in increased pellicle cleaning
ratio activity as well. A combination formula comprising 10%
preferred Zeodent 109 abrasive with 10% Zeodent 119 abrasive
produced PCR cleaning of 127 as compared with 83 produced
by a formula containing 20% Zeodent 119 alone.
(White Jr. ¶¶ 123, 124.)
5. International Silica Technologies (IST) teaches that “[f]umed
and precipitated silica are manufactured from crystalline silica . . . [which] is
strip mined or dredged. The process to convert the crystalline form to
amorphous silica is expensive, heavily energy dependent, and contributes
additional carbon dioxide to our atmosphere” (IST 1).
6. IST discloses StratoSil™, “a „NEW‟ silica” extracted from rice
hulls. According to IST, StratoSil™ “is 99.8% pure amorphous silica” and
its uses “include anticaking/flow agents, batteries, coatings, cosmetics,
defoamers, filtration, inks, rubber, and many other applications where fumed
and precipitated silica are used” (IST 1).
7. The present Specification discloses that:
[C]ertain biogenic silicas, namely those derived from rice hulls,
can provide highly effective dental abrasion result[s] within
dentifrices, either as the sole abrasive component therein, or as
a co-additive in combination with other abrasive materials. Of
particular advantage is the ability to tailor desired pellicle
cleaning (PCR) to radioactive dentin abrasion ratios(RDA)
through the combination of particularly selected co-additive
abrasive compounds in terms of their general abrasive qualities
and their proportion in relation to the amount of rice hull
derived silica present within a target dentifrice as well.
(Spec. 7.)
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8. According to the present Specification:
[T]he utilization of such rice hull derived silica products within
dentifrices provides surprisingly effective abrasion
characteristics. In combination with other known dental
abrasives, the results are highly unexpected in that such
combinations permit effective pellicle film cleaning with
simultaneous low levels (though still effective) abrasion. The
overall result has been found to provide the potential to hone
the pellicle film cleaning and radioactive dentin abrasion
characteristics of such overall abrasives. Such an ability meets
a certain level of need within the dentifrice industry . . . [for] an
abrasive or combination of abrasives that exhibit high pellicle
film cleaning (PCR) properties with simultaneously lower
radioactive dentin abrasion (RDA) results . . .
(Spec. 8).
9. The properties of STRAOSIL™ S-100, derived from rice hulls
and available from International Silica Technologies, are summarized in
Table 1 of the Specification. According to the Specification, “Example 1
was obtained as an unmilled, spray dried sample of STRATOSIL S-l 00 as is
demonstrated by its large particle size. Examples 2-4 were obtained as
milled samples” (Spec. 22).
Table 1 of the Specification is reproduced below:

(Spec. 22.)
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PRINCIPLES OF LAW
“[W]here the general conditions of a claim are disclosed in the prior
art, it is not inventive to discover the optimum or workable ranges by routine
experimentation.” In re Aller, 220 F.2d 454, 456 (CCPA 1955). In other
words, “the discovery of an optimum value of a variable in a known process
is normally obvious.” In re Antonie, 559 F.2d 618, 620 (CCPA 1977).
Exceptions to this rule include (1) the results of optimizing a variable were
unexpectedly good and (2) the parameter optimized was not recognized in
the prior art as one that would affect the results. Id.
OBVIOUSNESS
The Examiner finds that White Jr. discloses dentifrice compositions
containing about 6% to about 70% of a precipitated silica abrasive with a
mean particle size ranging from 8 to 14 microns and an Einlehner Abrasion
value of greater than about 7 (Ans. 4). The Examiner further finds that the
dentifrice compositions may contain additional abrasives, including other
precipitated silicas. The Examiner acknowledges that White Jr. does not
disclose that the silica abrasive is amorphous rice hull derived silica (id.).
The Examiner finds that International Silica Technologies (IST)
discloses STRATOSIL™, a relatively inexpensive, environmentally friendly,
99.8% pure amorphous silica derived from rice hulls (id. at 4-5). The
Examiner further finds that IST discloses that the “[p]otential uses of
StratoSil™ are applications where fumed silica and precipitated silicas are
used” (id. at 4).
The Examiner concludes that it would have been obvious to replace
the precipitated silica abrasive of White Jr.‟s dentifrices with IST‟s
STRATOSIL™, “motivated by the desire to use a silica that is high in purity,
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less expensive to make and environmentally friendly” (id. at 5), because
“IST discloses that potential uses of the amorphous rice hull silica include
applications where precipitated silicas are used” (id. at 6). The Examiner
further concludes that “it would have been obvious to optimize cleaning
characteristics while controlling the abrasivity of the [dentifrice]
composition . . . through routine experimentation by varying the amount of
each silica component in the composition” (id. at 5).
Appellants contend that it would not have been obvious to substitute
IST‟s rice hull silica for White Jr.‟s precipitated silica because “[r]ice hull
silica and precipitated silica are not the same, at least because rice hull silica
is a naturally occurring silica derived from rice, whereas precipitated silica is
prepared synthetically” (App. Br. 5), and “[t]here is nothing in IST or White
[Jr.] that indicates that rice hull silica and precipitated silica have equivalent
properties . . . [or that the] rice hull silica of IST would have provided (or
maintained) the properties exhibited by the specific dentifrices disclosed in
White [Jr.]” (id.).
In addition, Appellants contend that the rejection is untenable in light
of “unexpected results that are both superior and advantageous as secondary
indications of nonobviousness” (id. at 5-6). Specifically, Appellants contend
that even if “an abrasion value of 20.29 to 40.5 would have been expected
from rice hull silica, it would not have been expected that a dentifrice
including such a silica species would have scored as low as from 96 to 138
on the RDA scale” (id. at 7). Rather, Appellants contend that “such a
dentifrice would have been expected to score above 250 on the RDA scale”
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(id.). According to Declarant Dr. Fultz,
3
“[a]s the Brass Einlehner Abrasion
(BEA) value increases for a particular[] abrasive, the RDA value is expected
to increase accordingly” and indeed, “a silica abrasive that exhibits a BEA
value of as high as 20.29 would be expected . . . to score above 250 on the
RDA scale” (Decl. ¶¶ 9, 10), “particularly at higher loadings of from 10 to
35% by weight” (id. at ¶ 16). Thus, Dr. Fultz declares that “[t]he BEA and
RDA results were not only unforeseeable on the basis of White [Jr.] and IST,
but also surprising and unexpected based on what was known about silica
abrasives in general” (id.).
These arguments are not persuasive. While it‟s fair to say that rice
hull silica and precipitated silica are not the same, or equivalent in every
respect, IST explicitly discloses that highly pure STRATOSIL™ can be used in
many “applications where fumed and precipitated silica are used” (FF6), and
moreover, has a number of significant advantages over precipitated silicas
(FF5). Therefore, we agree with the Examiner that it would have been
obvious for one of ordinary skill in the art to replace at least the principal
precipitated silica in White Jr.‟s dentifrices with IST‟s STRATOSIL™, and
that it would have been obvious to use STRATOSIL™ of a size similar to the
size range disclosed for White Jr.‟s dentifrices.
As for the specific properties recited in claim 1, we emphasize that
certain properties are properties of the amorphous rice hull silica abrasive
itself. For instance, “a median particle size of from 4 to 48 microns” is a
property of the amorphous rice hull silica abrasive, as is an “Einlehner
Abrasion value of from 20.29 to 40.5 mg loss.” As acknowledged by

3
Declaration of co-inventor Dr. William C. Fultz, submitted April 7, 2010,
under the provisions of 37 C.F.R. § 1.132 (“Decl.”).
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Appellants, “[t]hese properties were not selected but rather observed by the
Applicant[s]” (Reply Br. 3) to be properties of samples of STRATOSIL™ S-
100, commercially available from International Silica Technologies (see
FF9). Thus, these easily ascertainable properties are simply part and parcel
of the abrasive itself, and the commercially available sizes of STRATOSIL™
encompass the size range disclosed as acceptable for use in dentifrices by
White Jr. (FF2). As for the Einlehner Abrasion values of STRATOSIL™
silicas, these, too, fall within the range disclosed as acceptable by White Jr.
(id.).
On the other hand, certain properties are properties of the dentifrice
composition, which can include a number of additional components,
including “any other dental abrasive component” (see e.g., claim 1). That is,
“a radioactive dentin abrasion value of from 96 to 138 and a pellicle
cleaning ratio to radioactive dentin abrasion (PCR:RDA) ratio of from 0.5 to
0.95” (required by claim 1) are properties of the dentifrice composition (id.).
To the extent Appellants contend that these values are unexpected, given the
observed Einlehner Abrasion values of the STRATOSIL™ abrasives, we are
not persuaded. Even accepting, as Dr. Fultz asserts, that dentifrice
compositions containing abrasives with higher Einlehner Abrasion values
would be expected to have correspondingly higher RDAs, White Jr. teaches
that the RDA of a dentifrice is at least in part a function of the mixture of
abrasives in the dentifrice (FF4). That is, the RDA can be adjusted by
including softer (i.e., less abrasive) silicas in the composition. The present
claims do not preclude the addition of other abrasives, and some explicitly
require it (see e.g., claims 2 and 3). Therefore, we agree with the
Examiner‟s conclusion that it would have been obvious, and within the level
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of ordinary skill in the art, to adjust the RDA of the composition to the
values disclosed as acceptable and/or desirable by White Jr. (FF3), “through
routine experimentation by varying the amount of each silica component in
the composition” (id. at 5).
SUMMARY
The rejection of claim 1 as unpatentable over White, Jr. and
International Silica Technologies is affirmed. Claims 2-7 have not been
separately argued, and fall accordingly.
TIME PERIOD FOR RESPONSE
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

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