Organik Kimya San. ve Tic. A.S.v.Rohm and Haas Company

Patent Trial and Appeal Board

Jun 26, 2015

09418395 (P.T.A.B. Jun. 26, 2015)

Trials@uspto.gov Paper 40
Tel: 571-272-7822 Entered: June 26, 2015

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

ORGANIK KIMYA AS,
Petitioner,

v.

ROHM AND HAAS COMPANY,
Patent Owner.
____________

Case IPR2014-00350
Patent 6,252,004 B1
_____________

Before TONI R. SCHEINER, LORA M. GREEN, and
ERICA A. FRANKLIN, Administrative Patent Judges.

FRANKLIN, Administrative Patent Judge.

FINAL WRITTEN DECISION
35 U.S.C. § 318(a) and 37 C.F.R. § 42.73
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I. INTRODUCTION
Organik Kimya AS (“Petitioner”) filed a Petition (Paper 2, “Pet.”) to
institute an inter partes review of claims 1–7 of U.S. Patent No. 6,252,004
B1 (Ex. 1001, “the ’004 patent”). Patent Owner, Rohm and Haas Company,
did not file a Preliminary Response to the Petition.
In an Institution Decision (Paper 9, “Inst. Dec.”), an inter partes
review of claims 1–7 was instituted. After the Institution Decision, Patent
Owner filed a Response (Paper 22, “PO Resp.”) and a contingent Motion to
Amend Claims (Paper 23, “Mot. Amend”). In response, Petitioner filed a
Reply (Paper 27, “Pet. Reply”) and an Opposition to the Motion to Amend
(Paper 28). Patent Owner then filed a Reply to Petitioner’s Opposition
(Paper 31). The parties presented arguments at an oral hearing (Paper 39,
“Tr.”).
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The Board has jurisdiction under 35 U.S.C. § 6(c). In this Final
Written Decision, issued pursuant to 35 U.S. C. § 318(a) and 37 C.F.R.
§ 42.73, we determine Petitioner has not shown by a preponderance of the
evidence that challenged claims 1–7 are unpatentable.
A. Related Matters
According to Petitioner and Patent Owner, the ’004 patent is involved
in a case titled Rohm and Haas Co. v. Organik Kimya San. Ve Tic. A.S.,
Case No. 13-cv-898-RGA, filed in the U.S. District Court for the District of
Delaware, currently stayed; and in an investigation at the U.S. International

1
Petitioner and Patent Owner have filed Objections to Demonstrative
Exhibits (Papers 37 and 38). In this Final Written Decision, we have not
considered any arguments presented in the demonstrative exhibits that were
not presented previously and/or are not supported by the record.
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Trade Commission titled In the Matter of Certain Opaque Polymers, Inv.
No. 337-TA-883 (USITC). Pet. 2–3; Paper 8, 2–3 (Related Matters).
B. The ’004 Patent (Ex. 1001)
The ’004 patent is directed to a process for preparing multi-stage
emulsion polymers having low dry-bulk density that are useful in coating
compositions, such as paints and paper coatings. Ex. 1001, Abstract.
Emulsion polymers, such as “hollow” or “voided” emulsion polymers, “are
generally prepared by swelling a core/shell emulsion polymer in such a way
that one or more voids form in the interior of the emulsion polymer particle.
These voids contribute, among other things, to the opacity of coatings and
films prepared with the hollow emulsion polymer.” Id. at 1:27–33. In some
applications, it is desirable to minimize the weight of an applied coating. Id.
at 1:34–35. “Accordingly, it is desirable to provide lightweight, low density
additives for coatings, such as voided latex particles.” Id. at 1:39–40. The
’004 patent explains that voided latex polymers are prepared by several
known processes, such as by swelling the core of a core-shell emulsion
polymer. Id. at 1:37–45. The ’004 patent states:
The present invention seeks to overcome the deficiencies
in the previously known processes by providing low density
voided emulsion polymers and a process for preparing them.

Id. at 1:56–58.
Specifically, the ’004 patent discloses preparing the multi-stage
emulsion polymer by sequential emulsion polymerization, which includes
charging the monomers which form the shell. Id. at 7:33–35. “At, or near,
the conclusion of charging the monomers which form the shell, the contents
of the reactor include the multistage polymer, water and unreacted
monomer.” Id. at 7:35–38. Under the conditions of emulsion
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polymerization, even if no additional monomer or initiator is added, there is
an appreciable free-radical content in the system that keeps the
polymerization process going until there is no longer an appreciable free-
radical content. Id. at 7:38–43. When no appreciable free-radical content
remains, no substantial amount of polymerization will occur. Id. at 7:43–46.
The ’004 patent states: “We have discovered that by providing an
aqueous emulsion of the multi-stage emulsion polymer, monomer and
swelling agent under conditions wherein there is no substantial
polymerization of the monomer, we can enhance the extent of swelling of
the multistage emulsion polymer.” Id. at 7:60–64.
The ’004 patent explains that suitable swelling agents may be volatile
or fixed bases, or combinations thereof, and “include, are those which, in the
presence of the multistage emulsion polymer and monomer, are capable of
permeating the shell and swelling the core.” Id. at 8:43–46.
C. Illustrative Claim
Independent claim 1 of the ’004 patent is illustrative of the claims at
issue:
1. A process for preparing emulsion polymer
particles comprising:
(a) providing an aqueous emulsion of
(i) multi-stage emulsion polymer, comprising a core
stage polymer and a shell stage polymer, wherein the
core stage polymer comprises, as polymerized units,
from 5 to 100 percent by weight, based on the weight
of the core stage polymer, of hydrophilic
monoethylenically unsaturated monomer, and from 0
to 95 percent by weight, based on the weight of the
core stage polymer, of at least one nonionic
monoethylenically unsaturated monomer; and
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wherein the shell stage polymer comprises, as
polymerized units, at least 50 percent by weight of
nonionic monoethylenically unsaturated monomer;
(b) adding an effective amount of one or more
polymerization inhibitors or reducing agents to substantially
stop any polymerization;
(c) providing monomer at a level of at least 0.5 percent
by weight based on the weight of the multi-stage emulsion
polymer;
(d) adding swelling agent; and
(e) reducing the level of monomer by at least fifty
percent.

Ex. 1001, 37:14–38:5.

D. The Prior Art
Touda et al., US 5,077,320, issued December 31, 1991 (Ex. 1003)
(“Touda”).

Toda et al., US 5,360,827, issued November 1, 1994 (Ex. 1004)
(“Toda”).

Overbeek et al., US 5,292,660, issued March 8, 1994 (Ex. 1005)
(“Overbeek”).

Crouch, US 2,574,020, issued November 6, 1951 (Ex. 1006)
(“Crouch”).

E. The Instituted Grounds of Unpatentability
Trial was instituted for Petitioner’s challenges claims 1–7 of the ’004
patent on the following grounds:
Reference Basis ’004 Claims Challenged
Touda § 103(a) 1–6
Touda and Overbeek § 103(a) 7
Toda and Crouch § 103(a) 1–7
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II. ANALYSIS
A. Claim Construction
In an inter partes review, claim terms in an unexpired patent are
interpreted according to their broadest reasonable constructions in light of
the specification of the patent in which they appear. See 37 C.F.R.
§ 42.100(b); In re Cuozzo Speed Techs., LLC, 778 F.3d 1271, 1280 (Fed.
Cir. 2015). Under the broadest reasonable construction standard, claim
terms are presumed to be given their ordinary and customary meaning, as
would be understood by one of ordinary skill in the art in the context of the
entire disclosure. In re Translogic Tech., Inc., 504 F.3d 1249, 1257 (Fed.
Cir. 2007). An inventor may rebut that presumption by providing a
definition of the term in the specification with reasonable clarity,
deliberateness, and precision. In re Paulsen, 30 F.3d 1475, 1480 (Fed. Cir.
1994). Stated differently, a “claim term will not receive its ordinary
meaning if the patentee acted as his own lexicographer and clearly set forth a
definition of the disputed claim term in either the specification or
prosecution history.” CCS Fitness, Inc. v. Brunswick Corp., 288 F.3d 1359,
1366 (Fed. Cir. 2002).
The parties’ arguments center on the construction of the following
claim term and phrase:
1. “swelling agent”
Claim 1 requires the inclusion of a swelling agent in the aqueous
emulsion. The Specification states,
Suitable swelling agents include, are those which, in the
presence of the multistage emulsion polymer and monomer, are
capable of permeating the shell and swelling the core. Swelling
agents may be aqueous or gaseous, volatile or fixed bases or
combinations thereof.
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Suitable swelling agents include volatile bases such as
ammonia, ammonium hydroxide, and volatile lower aliphatic
amines, such as morpholine, trimethylamine, and triethylamine,
and the like; fixed or permanent bases such as potassium
hydroxide, lithium hydroxide, zinc ammonium complex, copper
ammonium complex, silver ammonium complex, strontium
hydroxide, barium hydroxide and the like.

Ex. 1001 at 8:44–56. The Specification explains,
The core polymer of the multistage emulsion polymer
swells when the core is subjected to a basic swelling agent that
permeates the shell to at least partially neutralize the
hydrophilic-functionality of the core, preferably to a pH of at
least about 6 to at least about 10, and thereby result in swelling
by hydration of the hydrophilic core polymer.

Id. at 9:14–19.
Patent Owner asserts that that a person of ordinary skill in the art
would understand from the Specification that the term “swelling agent”
means
an ingredient that is capable of permeating the shell and
swelling the core of the multi-stage emulsion polymer (step (a))
in the presence of the swelling monomer (step (c)) under
conditions of no substantial polymerization (step (b)), in the
process in which the ingredient in question is being employed
as a “swelling agent.

PO Resp. 19–20. For example, according to Patent Owner, sodium
hydroxide, a fixed base, may be a swelling agent in some processes, while
not in others. Id. at 20. Patent Owner reasons that such a neutralizing agent
“may or may not also be a ‘swelling agent’ depending on the conditions of
the specific process where it is used.” Id. Patent Owner asserts, “[t]o
contend that ‘swelling agent’ does not have to involve any amount of
swelling ignores the functional aspects of the plain and ordinary meaning of
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term.” Id. at 24. Patent Owner’s position is supported by the Declaration of
Patent Owner’s Declarant, F. Joseph Schork, Ph.D. See Ex. 2005 ¶¶ 67–69.
Petitioner asserts that the claims do not require the recited “swelling
agent” to be an ingredient that “‘must be capable of permeating the shell and
swelling the core.’” Pet. Reply 4. Petitioner asserts that the Specification
“merely identifies exemplary types of swelling agents” without defining or
limiting the term. Id. at 5. In support of this assertion, Petitioner notes that
the Specification uses the term “include” in its description of suitable
swelling agents, i.e., “[s]uitable swelling agents include, are those which, in
the presence of the multistage emulsion polymer and monomer, are capable
of permeating the shell and swelling the core,” Ex. 1001, 8:44–46 (emphasis
added). Pet. Reply 5. According to Petitioner, by using the term “include,”
the Specification “mak[es] clear that swelling agents that are not capable of
permeating the shell and swelling the core also fall within the scope of the
invention.” Id. at 6. Petitioner asserts that Patent Owner’s proposed claim
construction disregards the Specification’s use of the term “include” in an
attempt “to change the meaning of the ‘004 patent disclosure” and to impart
impermissibly a “swelling step” into claim 1. Id.
We disagree with Petitioner that the Specification’s use of the term
“include,” when describing suitable swelling agents, “mak[es] clear” that
bases that are not capable of permeating the shell and swelling the core also
fall within the scope of the invention. Id. Rather, the Specification’s use of
the word “include,” in this instance, is modified by the phrase immediately
following it, i.e., “are those which,” suggesting that suitable swelling agents
include only those which exhibit the functional characteristic thereafter
described. See Ex. 1001, 8:44. In contrast, the subsequent paragraph of the
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Specification describes the structural requirement for suitable swelling
agents using the word “include,” without modifying it with a restrictive
phrase. Instead, when disclosing the volatile, fixed and permanent bases, the
word “include” is coupled with the phrases “such as” and “and the like,”
signaling open-ended or inclusive categories of these bases. See id. at 8:49–
56.
Further, we agree with Patent Owner that the Specification describes a
swelling agent not merely as being capable of permeating a shell and
swelling the core of a multistage emulsion polymer in the abstract, but
specifically under the conditions of the specific process for which the agent
is to be used. Indeed, the Specification explains that in its process for
preparing emulsion polymers, the core polymer of the multistage emulsion
polymer swells when it “is subjected to a basic swelling agent that permeates
the shell to at least partially neutralize the hydrophilic-functionality of the
core.” Ex. 1001, 9:14–17.
Based on the foregoing discussion, in light of the ’004 patent
Specification, we construe the claim term “swelling agent” as expressing a
structural element, i.e., “an aqueous or gaseous, volatile or fixed base, or
combinations thereof,” in functional terms, i.e., “capable of permeating the
shell and swelling the core, in the presence of the multistage polymer and
monomer, under the conditions of the specific process for which the agent is
to be used.” See Greenberg v. Ethicon Endo-Surgery, Inc., 91 F.3d 1580,
1583 (Fed. Cir. 1996) (structural elements, e.g., “filter” and “brake,” may be
expressed in functional terms).

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2. “adding an effective amount of one or more polymerization
inhibitors or reducing agents to substantially stop any polymerization”

Claim 1 requires “adding an effective amount of one or more
polymerization inhibitors or reducing agents to substantially stop any
polymerization.” The Specification states that “[w]hen used, the
polymerization inhibitors or reducing agents are added in effective amount
to substantially stop any polymerization, generally from 25 to 5,000 parts
per million (‘ppm’), preferably from 50 to 3,500 ppm based on polymer
solids.” Ex. 1001, 8:16–20 (emphasis added).
In our Institution Decision we interpreted the claim phrase “adding an
effective amount of one or more polymerization inhibitors or reducing
agents to substantially stop any polymerization,” as including, but not being
limited to, adding an amount of polymerization inhibitors or reducing agents
generally from 25 to 5,000 ppm, preferably from 50 to 3,500 ppm based on
polymer solids, or in amounts exceeding these ranges. Inst. Dec. 7.
Patent Owner asserts “‘an effective amount’ to ‘substantially stop
polymerization’ . . depends entirely on the specific inhibitor or reducing
agent and the specific reaction conditions of the process, including the
starting amount of monomer and residual initiator.” PO Resp. 18.
Therefore, according to Patent Owner, the claim phrase “adding an effective
amount of one or more polymerization inhibitors or reducing agents to
substantially stop any polymerization,” is not satisfied unless polymerization
is substantially stopped as a result of adding the inhibitor or reducing agent
used. Id. at 17.
Petitioner asserts that Patent Owner’s proposed interpretation
“produces an unworkable result,” as the Specification does not provide a
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quantitative way for determining whether the condition actually exists. Pet.
Reply 9. However, the Specification explains that no substantial
polymerization exists when there is a depletion of free-radicals. See Ex.
1001, 7:43–46 (“When there is no appreciable free-radical content, in other
words, when the radical flux is very low or approaches zero, then no
substantial amount of polymerization will occur.”).
Accordingly, based on the foregoing discussion, in light of the ’004
patent Specification, we determine that the broadest reasonable
interpretation of the claim phrase “adding an effective amount of one or
more polymerization inhibitors or reducing agents to substantially stop any
polymerization,” includes, but is not limited to, adding an amount of
polymerization inhibitors or reducing agents generally from 25 to 5,000
ppm, preferably from 50 to 3,500 ppm based on polymer solids, or in
amounts exceeding these ranges, and/or wherein no appreciable free-radical
content remains in the reactor including the multistage polymer and
unreacted monomer.
B. Obviousness over Touda
Petitioner contends that claims 1–6 would have been obvious over
Touda (Ex. 1003) under 35 U.S.C. § 103(a). Pet. 5, 20–29. Touda
discloses:
A process for producing polymer particles containing one
microvoid or two or more discrete microvoids, which comprises
(1) adding a base to a latex of a carboxyl-modified copolymer
containing 0.1 to 1000 parts of an organic solvent per 100 parts
by weight of the carboxyl-modified copolymer to neutralize at
least part of the carboxyl groups in the copolymer, and
(2) adding an acid to the latex to adjust the pH of the latex to
not more than 7.

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Ex. 1003, Abstract.

Touda explains that:

[T]he present inventors have found that if the polymer particles
are swollen with a base in the presence of an organic solvent,
microvoid-containing polymer particles can be obtained easily
with a short period of time, and microvoid-containing particles
of a polymer having a high glass transition temperature can be
obtained, and that this process can also give polymer particles
having a plurality of microvoids.
Id. at 2:41–48.
Further, Touda teaches that “[t]here is no particular limitation on the
method of obtaining polymers containing carboxyl groups,” and discloses
that the method may include copolymerizing carboxyl-containing
monomers, which “is advantageous to production.” Id. at 2:66–3:4. Touda
discloses that exemplary carboxyl-containing monomers that can be used in
the invention include ethylenically unsaturated carboxylic acids, such as
methacrylic acid, and that exemplary monomers, which are copolymerizable
with carboxyl-containing monomers, include aromatic vinyl monomers, such
as styrene. Id. at 3:5–8, 25–29.
Additionally, Touda teaches that “[t]here is no particular restriction on
the method of including an organic solvent in the carboxyl-modified
copolymer latex,” and the method may, for example, involve adding an
organic solvent to a latex obtained by polymerization. Id. at 3:61–64. The
organic solvent used in the invention also is not particularly limited, as long
as it “can fully swell the copolymer particles.” Id. at 3:66–4:1. Touda
discloses specific examples of solvents, including toluene. Id. at 4:1–3.
Petitioner asserts that Touda discloses each and every element of
claim 1 of the ’004 patent. Pet. 20. According to Petitioner, “Touda
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expressly discloses all but two of the elements of claim 1 of the ’004 patent
in a single example – Example 2 (combination of Examples 1S, 2A and
2B).” Id. at 20 (citing Ex. 1002 ¶ 55). Petitioner asserts that the two
elements not disclosed in Touda Example 2 are taught expressly elsewhere
in the disclosure of Touda. Id.
Touda discloses in Example 1S the “[s]ynthesis of a seed latex,”
comprising: placing 300 parts of deionized water in a reactor, along with 95
parts of styrene (i.e., 95% of a nonionic monoethylenically unsaturated
monomer), and 5 parts of MAA (i.e., 5% of a hydrophilic monoethylenically
unsaturated monomer); heating and stirring the mixture; allowing the
temperature of the mixture to reach 70° C and then adding 17 parts of a 3%
aqueous solution of potassium persulfate; and maintaining the reaction
mixture at 70° C for three hours to complete the polymerization reaction,
resulting in a polymerization conversion of 99%. Ex. 1004, 6:33–49; Pet.
36.
Touda discloses in Example 2A the “[p]roduction of a filled polymer
latex in the presence of an organic solvent,” comprising charging the same
reactor used in the production of the seed latex with 508 parts of deionized
water, 3.4 parts of seed latex [S]; heating the contents to 80° C; adding 30
parts of a 3% aqueous solution of potassium persulfate; adding a mixture of
a monomeric mixture composed of 87.7 parts of styrene (i.e., at least 50% by
weight of nonionic monoethylenically unsaturated monomer), 0.3 parts of
divinylbenzene, 5 parts of methyl methacrylate and 7 parts of MAA and 10
parts of toluene over 6 hours; and then maintaining the mixture at 80° C for
2 hours to complete the polymerization reaction. Ex. 1004, 7:35–56.

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Touda discloses in Example 2B the production of a microvoid-
containing latex, comprising: charging the same reactor used in the
production of the seed latex with 870 parts of deionized water, 100 parts of
the filled polymer latex, 1 part of sodium dodecyl-benzenesulfate, 50 parts
of toluene, and 33 parts of a 10% aqueous solution of sodium hydroxide;
stirring the mixture at 80° C for three hours; adding 300 parts of a 1%
aqueous solution of hydrochloric acid; stirring the mixture at 80° C for 3
hours; cooling the reaction mixture to room temperature; and removing the
organic solvent under reduced pressure. Id. at 7:58–62; see also id. at 7:4–
24.
Petitioner asserts that although Touda Example 2 does not expressly
disclose adding an effective amount of one or more polymerization
inhibitors to substantially stop any polymerization, it would have been
obvious to a person of ordinary skill in the art at the time the invention was
made to have modified the process of Touda’s Example 2A by substituting
10 parts of cresol, an organic solvent and polymerization inhibitor, in place
of the disclosed 10 parts of toluene organic solvent. Pet. 23. Petitioner
reasons that the artisan would have been motivated to make this
modification because Touda teaches that there is no particular restriction on
the type of organic solvent used, and explicitly discloses cresol as an
exemplary organic solvent. Id. at 22 (citing Ex. 1003, 3:61–63,4:7).
Patent Owner asserts a person of ordinary skill in the art would have
understood that cresol is an inhibitor, and that substituting it for toluene in
Touda’s Example 2A would have “shut down the polymerization reaction.”
PO Resp. 41 (citing Ex. 2005 ¶ 128). Patent Owner asserts that in Example
2A, toluene is added as part of a mixture including monomers during a “6-
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hour polymerization step that results in the formation of the shell polymer as
part of a ‘filled polymer latex.’” Id. at 41 (citing Ex. 1003, 7:34–55).
Therefore, Patent Owner asserts that a person of ordinary skill in the art
would not use cresol, a polymerization inhibitor, in place of toluene, during
this step because doing so would prevent polymerization and formation of
the shell polymer. Id. (citing Ex. 2005 ¶ 128).
Petitioner acknowledges that substituting cresol for toluene
“shortstops the polymerization reaction.” Pet. Reply 2–3. However,
Petitioner asserts that doing so does not prevent the formation of a
multistage polymer particle. Id. In support of this assertion, Petitioner relies
on experimental results detailed in the Declaration of Dr. Schork, Patent
Owner’s witness. According to Petitioner, Dr. Schork’s experiment
involving substituting cresol for toluene in Touda’s Example 2A, “confirms
that a meaningful amount of shell stage polymer (approximately 17 wt. %
based on wt. % of the multi-stage polymer particle) was formed.” Id. at 3
(citing Ex. 2005 ¶ 128, Ex. I), 13 (citing Ex. 1001, 7:24–27).
After considering the arguments and evidence, we find that Patent
Owner has established that a person of ordinary skill in the art would not
have been motivated to substitute cresol for toluene in step 2A of Touda’s
Example 2. Although cresol and toluene are both solvents, Patent Owner
has established with persuasive evidence that cresol’s additional function as
a polymerization inhibitor would have defeated the purpose of the solvent in
Touda’s step 2A. That step is directed to the production of a filled polymer
latex (multi-stage polymer). Ex. 1003, 7:35–56. During step 2A, toluene
was added to a monomeric mixture over the course of 6 hours. Id. at 7:49–
50. Then the mixture was maintained at 80 °C for 2 hours to complete the
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polymerization reaction. Id. at 7:51–52.
Dr. Schork attempted to replicate Example 2 with cresol substituting
for toluene during step 2A, as proposed by Petitioner. Ex. 2005 ¶¶ 92–95
(citing Declaration Ex. I, “Synthesis Procedure for Touda ’320 Example 2
Modified”). Dr. Schork explained that the result observed from using cresol
during step 2A was not surprising: “monomer was only 2.5% converted to
polymer after the required eight hours.” Id. ¶ 95. Dr. Schork stated, “[i]n
my opinion, these results show that the modified process of Example 2A
does not make a core-shell emulsion polymer having a core stage and a shell
stage because the cresol inhibits polymerization during the phase intended to
make the shell.” Id. Petitioner’s assertion to the contrary—that Dr.
Schork’s experiment produced “a meaningful amount of shell stage
polymer,”—is merely attorney argument unsupported by any persuasive
evidence. Pet. Reply 13. Indeed, Petitioner’s Declarant, Marek W. Urban,
Ph.D., did not attempt to replicate Example 2 with the modifications
proposed by Petitioner, i.e., substituting cresol for toluene in Step 2A.
Accordingly, we conclude that Petitioner has not established that it
would have been obvious to modify Touda’s Example 2 to include a
polymerization inhibitor.
Moreover, we agree with Patent Owner that Touda’s Example 2 also
does not include a swelling agent, as required by claim 1 of the ’004 patent.
PO Resp. 28. In particular, as Patent Owner asserts, Touda does not disclose
expressly sodium hydroxide, or any other base, as a “swelling agent,” i.e.,
being capable of permeating the shell and swelling the core of the emulsion
polymer under the conditions of Example 2. Id.
Petitioner asserts that even if our construction of “swelling agent”
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requires a base that permeates the shell and swells the core, Petitioner “has
established a prima facie case of inherency under Office practice.” Pet.
Reply 10 (citing In re Best, 562 F.2d 1252, 1254 (C.C.P.A. 1977); In re
Spada, 911 F.2d 705, 707–08 n.3 (Fed. Cir. 1990); In re Mousa, 479 F.
App’x. 348, 353 (Fed. Cir. 2012)), 14. According to Petitioner, sodium
hydroxide inherently permeates the shell and swells the core of the polymer
particles in Touda because the same polymer particles are described in the
’004 patent as suitable for swelling. Pet. Reply 14.
However, Dr. Schork explains that in Touda’s Example 1S, the core is
only 5 parts (5%) methacrylic acid and the shell in Example 2A is only 6
parts (6%) acrylic acid, such that the core and the shell are only slightly
acidic. Ex. 2005 ¶ 77. Dr. Schork states that a person of skill in the art
“would understand that under these conditions, NaOH would at best
neutralize the shell, not the core.” Id. According to Dr. Schork, “[g]iven the
low levels of acid, the NaOH would be unlikely to permeate and neutralize
any part of the particle. Certainly, NaOH would not permeate the shell and
swell the core. Instead, to the extent that any swelling occurred, it would
take place in the shell.” Id. Again, we are persuaded by Dr. Schork’s
testimony and do not find that Petitioner has provided persuasive evidence
contradicting Dr. Schork’s opinion.
Accordingly, after considering the arguments and evidence, and based
upon our construction of the term “swelling agent,” we find that Petitioner
has not established that Touda discloses sodium hydroxide as a “swelling
agent” in the process of Example 2.
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Based on the foregoing discussion and the record, we conclude that
Petitioner has not shown by a preponderance of the evidence that claims 1–6
would have been obvious over Touda under 35 U.S.C. § 103(a).
C. Obviousness over Touda and Overbeek
Petitioner contends that claim 7 would have been obvious over Touda
and Overbeek under 35 U.S.C. § 103(a). Pet. 6, 29–30. Claim 7 recites,
“The process of claim 1 wherein the level of monomer is reduced to less
than 10,000 ppm based on polymer solids by polymerizing said monomer.”
Petitioner asserts that Touda teaches or suggests each element of
independent claim 1, and combines Overbeek with Touda to teach the
further limitation of dependent claim 7, i.e., that the level of monomer in the
emulsion is “reduced to less than 10,000 ppm based on polymer solids by
polymerizing said monomer.” Pet. 18, 29.
Because Petitioner relies on Touda as teaching or suggesting adding a
“swelling agent” and one or more “polymerization inhibitors,” in the same
manner set forth regarding claim 1, we conclude that Petitioner has not
shown by a preponderance of the evidence that claim 7 would have been
obvious over Touda and Overbeek under 35 U.S.C. § 103(a).
D. Obviousness over Toda and Crouch
Petitioner asserts that claims 1–7 would have been obvious over Toda
(Ex. 1004) and Crouch (Ex. 1006) under 35 U.S.C. § 103(a). Pet. 6, 38–46.
Toda discloses:
A process for preparation of latex of a hollow polymer which
comprises adding a base, in the presence of a monomer, to latex
containing carboxy-modified copolymer particles to make the
pH of the latex 8 or more; adding a carboxyl group-containing
monomer to make the pH of the latex 7 or less; and then
polymerizing these monomers.
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Ex. 1004, Abstract.
In Example 11, Toda discloses a process for obtaining a latex
containing polymer particles comprising the steps of forming a center layer,
an intermediate layer, and a surface layer. Id. at 11:59–68; 12:13–37;
12:61–68; 13:1–2; Table 2. The center layer was formed by placing in a
reactor 400 parts of deionized water, 0.3 part of monomer mixture (a)( i.e.,
70% of methyl methacrylate (“MMA”)), 5% of butyl acrylate (“BA”) and
25% of MAA, and 0.3 part of an emulsifier; heating the mixture to 80° C
and stirring to prepare an emulsion; adding 7 parts of aqueous 3% potassium
sulfate (“KPS”) solution; subjecting the mixture to polymerization at 80° C
for 0.5 hour to obtain seed particles; adding 0.5 part of an emulsifier;
continuously adding the residual monomer mixture (a) over a period of one
hour; and carrying out polymerization for 2 hours, resulting in a conversion
of monomer mixture (a) of 98%. Id. An intermediate layer was formed by
adding to the reactor 7 parts of KPS; continuously adding monomer mixture
(b) (i.e., 87% of MMA, 10% of BA and 3% of MAA); and carrying out
polymerization for 4 hours, resulting in a conversion of mixture (b) of 98%.
The surface layer was formed by adding 7 parts of KPS to the reactor;
continuously adding a monomer (c), i.e., 100% of styrene; and carrying out
polymerization for 4 hours, lowering the temperature to 20° C to obtain
latex-containing polymer particles, wherein the conversion of monomer
mixture (c) was 98%. Id.
Toda further discloses in Example 11: (i) adding 3 parts of styrene to
the obtained latex containing polymer particles to soften the particles;
adding aqueous 10% potassium hydroxide solution and heating to 80° C for
3 hours (base treatment); (ii) adding 80 parts of aqueous MAA and 50 parts
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of styrene and stirring the mixture at 80° C for 3 hours (acid treatment); and
(iii) adding 10 parts of aqueous 3% KPS solution, stirring the mixture of
unreacted monomers at 80°C for 2 hours to carry out copolymerization,
resulting in a polymerization conversion at this final stage of 99%. Id. at
12:38–59,Table 2.
Petitioner asserts that Toda discloses, in at least Example 11, each and
every element of claims 1–7 of the ’004 patent, except for adding a
polymerization inhibitor. Pet. 39–41. Petitioner asserts that Toda,
“however, teaches that ‘[w]hen it is desired to make a base treatment at a
lower temperature, it is sufficient to lower polymerization conversion’ and
suggests polymerization conversions of 83% to 99%.” Id. at 41 (citing Ex.
1004, 6:43–48). Toda does not specifically explain how to lower the
polymerization conversion, but Petitioner asserts that Crouch discloses
“adding hydroquinone [a polymerization inhibitor] or other novel reducing
agents to a polymerizing emulsion to substantially stop polymerization after
a desired degree of polymerization has been obtained.” Id. (citing Ex. 1002
¶¶ 88–89). Petitioner contends, therefore, that in view of the combined
teachings of Toda and Crouch, it would have been obvious to one of
ordinary skill in the art to add hydroquinone in the process of Toda’s
Example 11 to shortstop the emulsion polymerization, lower the monomer
conversion, and to lower the temperature during which the base treatment is
conducted by adding hydroquinone, as taught by Crouch. Id. at 42.
Based on our construction of the term “swelling agent,” and in
consideration of the arguments and evidence, we find that the Petitioner has
not established persuasively that the process disclosed in Toda’s Example 11
includes adding a “swelling agent.” According to Petitioner, in Example 11,
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“[i]mmediately after the ‘softening step,’ aqueous potassium hydroxide
solution was added as a swelling agent.” Pet. 43. Petitioner supports this
position by referring to Toda’s disclosure of adding potassium hydroxide
solution in the process of Example 11, Pet. 43 (citing Ex. 1004, 12:40–43,
Table 2) and the testimony of Petitioner’s Declarant, Dr. Urban, who
explains that potassium hydroxide “is a fixed base expressly identified by
the ’004 patent as a possible swelling agent” (Ex. 1002 ¶ 92)).
In the Response, Patent Owner asserts that Toda does not describe
potassium hydroxide as being “capable of permeating the shell and swelling
the core” of the multi-stage emulsion polymer prepared by Example 11. PO
Resp. 33. Further, Patent Owner asserts that a person of ordinary skill in the
art would not understand the potassium hydroxide disclosed in Toda to be a
“swelling agent.” Id. (citing Ex. 2005 ¶ 99). In Toda’s Example 11, the
reaction temperature is lowered to 20 °C before adding the potassium
hydroxide. Id. (citing Ex. 1004, 12:34–36). According to Dr. Schork, a
person of ordinary skill in the art would understand that at that temperature,
the polystyrene shell would be too hard for potassium hydroxide to permeate
it. Ex. 2005 ¶¶ 100, 149. Additionally, Dr. Schork explained that a person
of ordinary skill would understand that after the reaction is heated back up to
80 °C, the shell would still be too rigid for potassium hydroxide “to
permeate under the conditions of the base treatment with ‘3 parts of
styrene.’” Id. ¶149.
Further, Patent Owner asserts that Dr. Schork’s attempt to replicate
the process of Example 11 confirms that the added potassium hydroxide is
not a “swelling agent.” Id. at 33, 56 (citing Ex. 2005 ¶¶ 117–120).
According to Dr. Schork, his replication of Example 11, incorporating the
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modification proposed by Petitioner (i.e., adding hydroquinone to shortstop
the reaction monomer mixture (c)), provided “no evidence of swelling
during the base treatment step.” Ex. 2005 ¶147.
In its Reply, Petitioner argues that even if our construction of
“swelling agent” requires a base that permeates the shell and swells the core,
Toda discloses such a system. Pet. Reply 14. According to Petitioner,
potassium hydroxide inherently permeates the shell and swells the core of
the polymer particles in Toda because the same polymer particles are
described in the ’004 patent as suitable for swelling. Id.
As discussed previously, we have construed the claim term “swelling
agent” as encompassing a structure, i.e., a base, and a function, i.e., being
capable of permeating the shell and swelling the core, in the presence of the
multistage polymer and monomer, under the conditions of the specific
process for which the agent is to be used. We are not persuaded by
Petitioner’s assertion that potassium hydroxide permeates the shell and
swells the core of the polymer particles in Toda merely because the same
polymer particles are described in the ’004 patent as suitable for swelling.
Pet. Reply 14. In Toda’s Example 11, the potassium hydroxide was added
to the mixture after the temperature of the mixture was lowered to 20° C and
styrene was added to soften the polymer particles. Ex. 1004, 12:38–42.
Patent Owner provides persuasive evidence, through the Declaration of Dr.
Schork, that a person of ordinary skill in the art would have understood that
the shell would be too hard at this temperature for potassium hydroxide to be
capable of permeating the shell and swelling the core. PO Resp. 33–34
(citing Ex. 2005 ¶ 100). Petitioner has not argued persuasively otherwise.
See, e.g., Pet. Reply 13–14.
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Further, in Toda’s Example 11, after adding the potassium hydroxide,
the mixture is heated to 80 °C. Ex. 1003, 12:41–44. Patent Owner provides
persuasive evidence, also through the Declaration of Dr. Schork, that based
on the teachings of Toda, a person of ordinary skill in the art would not
expect potassium hydroxide to permeate the shell and swell the core at that
temperature either. PO Resp. 34 (citing Ex. 2005 ¶ 100). Petitioner has not
argued persuasively otherwise. See, e.g., Pet. Reply 13–14.
Additionally, Patent Owner provides persuasive experimental
evidence that the potassium hydroxide solution used in Toda’s Example 11
is not capable of permeating the shell and swelling the core. See PO Resp.
33, 36, 56 (citing Ex. 2005 ¶¶ 117–120). Dr. Schork replicated Toda’s
Example 11, incorporating the modification proposed by Petitioner, i.e.,
adding hydroquinone to shortstop the reaction monomer mixture (c). Ex.
2005 ¶¶ 117–118. Dr. Schork explained that after the potassium hydroxide
was added, “the heating of the reactor back to 80 °C was initiated, but was
not achieved because the entire reactor gelled to a viscous mass that could
not be stirred.” Id. ¶ 119. Dr. Schork stated, “TEM [transition electron
microscopy] data of the final product and in-process samples ([Declaration]
Ex. P) confirms that modified Example 11 did not result in voided or
swollen emulsion particles.” Id. ¶ 120. Indeed, according to Dr. Schork,
modified Example 11 did not even produce multi-stage emulsion particles
with a separate core and shell. Id. Dr. Schork concluded, “Based on my
replication of Example 11, including analysis of the TEM images, there is no
evidence of swelling during the base treatment step.” Ex. 2005 ¶147.
Petitioner has not provided any experimental data or evidence
contradicting Dr. Schork’s results and findings.
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Accordingly, after considering the arguments and evidence, and based
upon our construction of the term “swelling agent,” we find that Petitioner
has not shown that Toda discloses potassium hydroxide as a “swelling
agent” in the process of Example 11.
Based on the foregoing discussion and the record, we conclude that
Petitioner has not shown by a preponderance of the evidence that Toda and
Crouch render obvious claims 1–7.
III. MOTION TO AMEND
Patent Owner’s Motion to Amend is contingent on claims of the ’004
patent being held unpatentable. Mot. Amend 1. Because these claims are
not held to be unpatentable, there is no occasion to reach or decide the
motion to amend.
IV. CONCLUSION
Petitioner has not demonstrated by a preponderance of the evidence
that claims 1–7 instituted for inter partes review are unpatentable under
35 U.S.C. § 103(a) as obvious over Touda, Touda and Overbeek, or Toda
and Crouch.
ORDER
In consideration of the foregoing, it is hereby:
ORDERED that Petitioner’s request for cancellation of claims 1–7 of
the ’004 patent is denied;
FURTHER ORDERED that Patent Owner’s Motion to Amend is
dismissed as moot; and
FURTHER ORDERED that, because this is a Final Written Decision,
parties to the proceeding seeking judicial review of the decision must
comply with the notice and service requirements of 37 C.F.R. § 90.2.
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PETITIONER:

Timothy P. McAnulty
Erin M. Sommers
Eric J. Fues
FINNEGAN, HENDERSON, FARABOW
GARRETT & DUNNER, LLP
timothy.mcanulty@finnegan.com
erin.sommers@finnegan.com
eric.fues@finnegan.com

PATENT OWNER:

Evangeline Shih
Frank C. Calvosa
Raymond N. Nimrod
James E. Baker
QUINN EMANUEL URQUHART & SULLIVAN LLP
evangelineshih@quinnemanuel.com
frankcalvosa@quinnemanuel.com
raymondnimrod@quinnemanuel.com
jamesbaker@quinnemanuel.com