UNITED STATES PATENT AND TRADEMARK OFFICE
`
`____________
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`
`____________
`
`SOLENIS LLC
`
`Petitioner,
`
`v.
`
`ECOLAB USA INC.
`
`Patent Owner.
`
`____________
`
`Case IPR2016-01281
`Patent 8,465,623
`
`____________
`
`PATENT OWNER’S RESPONSE UNDER 37 C.F.R. § 42.120
`
`
`
`
`
`

`

`I.
`II.
`
`Table of Contents
`Introduction ...................................................................................................... 1
`Background of the Invention ........................................................................... 4
`A.
`State of the art prior to the ’623 patent ................................................. 4
`B.
`The invention of the ’623 patent ........................................................... 8
`C.
`Summary of the applied references ..................................................... 11
`1.
`Chung ........................................................................................ 12
`2.
`Brown ........................................................................................ 13
`3.
`Kimura ...................................................................................... 15
`4.
`Laufmann .................................................................................. 16
`III. Applicable Legal Principles ........................................................................... 17
`A.
`Standard for inter partes review .......................................................... 17
`B.
`The law of anticipation and obviousness ............................................ 18
`IV. Level of Skill in the Art ................................................................................. 21
`V.
`Claim Construction ........................................................................................ 23
`VI. Argument ....................................................................................................... 24
`A. Grounds 6 & 7: No combination of Chung, Brown, and
`Laufmann renders the claims obvious. ................................................ 25
`1.
`No combination of Chung, Brown, and Laufmann teaches
`combining pretreated filler with fiber prior to addition of a
`strength or drainage aid as required by claims 1-8, 12,
`13, and 16-19. ............................................................................ 25
`No combination of Chung, Brown, and Laufmann teaches
`the additional relationships between the composition of
`matter and the strength or drainage aid required by claims
`16 and 19. .................................................................................. 31
`B. Grounds 4 & 5: No combination of Brown, Kimura, and
`Laufmann renders the claims obvious. ................................................ 35
`
`2.
`
`
`
`i
`
`

`

`1.
`
`2.
`
`No combination of Brown, Kimura, and Laufmann teaches
`combining pretreated filler with fiber prior to addition of a
`strength or drainage aid as required by claims 1-8, 12,
`13, and 16-19. ............................................................................ 35
`No combination of Brown, Kimura, and Laufmann teaches
`the additional relationships between the composition
`of matter and the strength or drainage aid required by
`claims 16 and 19. ...................................................................... 38
`C. Grounds 1 & 2: No combination of Kimura and Laufman renders
`the claims obvious. .............................................................................. 41
`1.
`No combination of Kimura and Laufmann teaches
`combining pretreated filler with fiber prior to addition of a
`strength aid as required by claims 1-8, 12, 13, and 16-19. ....... 41
`No combination of Kimura and Laufmann teaches the
`additional relationships between the composition of matter
`and the strength or drainage aid required by claims 16 and
`19. .............................................................................................. 44
`D. Ground 3: Kimura does not anticipate claim 19. ................................ 47
`E.
`The declaration of Dr. Dyer should be afforded little, if
`any, weight. ......................................................................................... 50
`1.
`Dr. Dyer’s work experience with filler pretreatment
`consists of work on the patented technology. ........................... 50
`“Hear[ing] things” from unknown individuals, at unknown
`locations, at unknown times, with unknown content does
`not constitute “experience” with filler pretreatment. ................ 54
`Dr. Dyer’s analysis is impermissibly infected with
`hindsight. ................................................................................... 56
`VII. Conclusion ..................................................................................................... 57
`
`2.
`
`2.
`
`3.
`
`
`
`ii
`
`
`
`
`
`

`

`
`TABLE OF AUTHORITIES
`
` Page(s)
`
`Cases
`Apple Inc. v. Samsung Elecs. Co.,
`839 F.3d 1034 (Fed. Cir. 2016) (en banc) .................................................... 18, 19
`Cheese Sys. v. Tetra Pack Cheese & Powder Sys.,
`725 F.3d 1341 (Fed. Cir. 2013) .......................................................................... 20
`Cont’l Can Co. USA, Inc. v. Monsanto Co.,
`948 F.2d 1264 (Fed. Cir. 1991) .......................................................................... 20
`DePuy Spine, Inc. v. Medtronic Sofamor Danek, Inc.,
`567 F.3d 1314 (Fed. Cir. 2009) .......................................................................... 19
`Dynamic Drinkware, LLC v. Nat’l Graphics, Inc.,
`800 F.3d 1375 (Fed. Cir. 2015) .......................................................................... 18
`Edmund Optics, Inc. v. Semrock, Inc.,
`IPR2014-00599, Paper 72 ................................................................................... 20
`In re Gordon,
`733 F.2d 900 (Fed. Cir. 1984) ...................................................................... 19, 30
`Harmonic Inc. v. Avid Tech., Inc.,
`815 F.3d 1356 (Fed. Cir. 2016) .......................................................................... 17
`In re ICON Health & Fitness, Inc.,
`496 F.3d 1374 (Fed. Cir. 2007) .......................................................................... 20
`Leo Pharm. Prods. v. Rea,
`726 F.3d 1346 (Fed. Cir. 2013) .......................................................................... 18
`In re Magnum Oil Tools Int’l, Ltd.,
`829 F.3d 1364 (Fed. Cir. 2016) .......................................................................... 19
`Oracle Corp. v. Crossroads Sys., Inc.,
`IPR2014-01207, .................................................................................................. 21
`
`
`
`iii
`
`

`

`Par Pharm. v. TWI Pharms. Inc.,
`773 F.3d 1186 (Fed. Cir. 2014) .......................................................................... 20
`Phigenix v. Immunogen,
`IPR2014-00676 ................................................................................................... 19
`Plantronics, Inc. v. Aliph, Inc.,
`724 F.3d 1343 (Fed. Cir. 2013) .......................................................................... 21
`Plas-Pak Industries v. Sulzer Mixpac AG,
`600 F. App’x 755 (Fed. Cir. 2015) ............................................................... 19, 30
`Rambus Inc. v. Rea,
`527 Fed. Appx. 902 (Fed. Cir. June 28, 2013) ................................................... 18
`In re Ratti,
`270 F.2d 810 (CCPA 1959) .......................................................................... 19, 30
`In re Robertson,
`169 F.3d 743 (Fed. Cir. 1999) ............................................................................ 20
`Summit 6 v. Samsung Elecs. Co.,
`802 F.3d 1283 (Fed. Cir. 2015) .......................................................................... 18
`Statutes
`35 U.S.C. § 316(e) ................................................................................................... 17
`Other Authorities
`37 C.F.R. § 42.1(d) .................................................................................................. 17
`37 C.F.R. § 42.120 ..................................................................................................... 1
`MPEP §§ 2143.01(V) and (VI) ................................................................................ 19
`
`
`
`
`iv
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`

`

`I.
`
`
`Introduction
`Claims 1-8, 12, 13, and 16-19 of United States Patent No. 8,465,623 (“the
`
`’623 patent”) are patentable over the prior art cited by Petitioner. The challenged
`
`claims are directed to a novel method of papermaking that produces superior and
`
`unexpected synergistic effects. These effects are achieved by the application of
`
`certain chemical compositions and by the combination of certain components in a
`
`particular order. Even if some features of the claims can be found spread
`
`throughout various prior art references, identifying and combining those features is
`
`possible only by using the ’623 patent as a roadmap. A person of ordinary skill
`
`would have had no reason to combine the references as suggested by Petitioner,
`
`nor any reasonable basis to expect success in so doing.
`
`Since the Board’s institution decision, Patent Owner has developed the
`
`record through expert testimony from its own expert, Robert Pelton, Ph.D., and
`
`through the deposition of Petitioner’s declarant, David Dyer, Ph.D. Unlike Dr.
`
`Dyer, Dr. Pelton is a chemist specializing in papermaking chemistry. The
`
`additional evidence offered by Patent Owner completes the record, and confirms
`
`the challenged claims are patentable for at least three reasons.
`
`First, the order of combination of components in a papermaking process
`
`matters. The state of the art as of the ’623 patent’s priority date provided no
`
`suggestion to add a filler to cellulose fiber stock before combining the cellulose
`
`
`
`1
`
`

`

`fiber stock with a strength or drainage aid, particularly where a treatment had been
`
`applied to the filler. As further explained by Dr. Pelton, the addition of filler to
`
`cellulose fiber stock under previous methods of papermaking resulted in the filler
`
`interfering with fiber-fiber bonds, which were critical to paper strength. Prior art
`
`treated filler, such as that disclosed in Kimura, was introduced only in limited
`
`amounts or not at all until after adding the strength aid to the fiber stock. A person
`
`of skill would not have been motivated to attempt alteration of this order, as doing
`
`so would require reevaluation of other relevant variables, such as characteristics of
`
`the filler, characteristics of any pretreatment applied, and the nature of the strength
`
`aid.
`
`Second, while claims 16 and 19 of the ’623 patent are expressly directed to
`
`methods for ensuring certain components of the papermaking process repel or
`
`resist each other, the state of the art at the relevant time was concerned with
`
`causing components in that process to hold together. To that end, the filler
`
`dispersion of Brown, for example, was made using anionic and cationic materials;
`
`and anionic and cationic components were added to the fiber and filler mixture in
`
`Chung. The treatment of filler with the polyion complex taught by Kimura was
`
`also designed to promote aggregation, not to repel a later-added strength or
`
`drainage aid.
`
`
`
`2
`
`

`

`None of the cited prior art teaches the selective repulsion of claim 16,
`
`wherein the composition of matter selected for pretreatment of filler particles is
`
`designed to repel the later-added strength or drainage aid by having the same
`
`charge. None of the cited prior art addresses or even contemplates the reduced
`
`adherence of claim 19, wherein the filler particles are treated with a composition of
`
`matter designed to inhibit their adherence to the later-added strength or drainage
`
`aid. That mechanism was conceived by the inventors of the ’623 patent and
`
`represented a paradigm shift in the papermaking industry.
`
`Third, a person of ordinary skill in the art would not have modified or
`
`combined the alleged prior art in the ways Petitioner urges. Petitioner’s proposed
`
`modifications and combinations of references flout basic principles of obviousness
`
`law. Hindsight pervades Petitioner’s obviousness grounds. Indeed, Petitioner’s
`
`expert was not even instructed to try to avoid use of hindsight in reaching his
`
`conclusions. And, in relying on his own “experience” with filler pretreatment, Dr.
`
`Dyer necessarily relies on information learned after the critical date and as part of
`
`his confidential research conducted with the company that conceived of the
`
`invention of the ’623 patent. Dr. Dyer had no prior experience with filler
`
`pretreatment, and his conclusory assertion that he relied on things learned by
`
`“attending conferences, hearing information, networking with people” is not
`
`credible, particularly in view of his inability to identify a single detail about any
`
`
`
`3
`
`

`

`such event. (EX2017 at 50:5-9; 54:9-60:7.) Using the teachings of the ’623 patent,
`
`whether from its written specification or from his own work with the ’623 patent’s
`
`inventors, as a roadmap through the prior art is the definition of improper
`
`hindsight.
`
`
`
`The papermaking process and papermaking chemistry are complex. Dr. Dyer
`
`admits that there are literally hundreds of variables in a papermaking system, and
`
`that changes to one aspect of the process have multiple and unpredictable effects
`
`on other aspects. (EX2017 at 108:12-14; and 125:23-126:19; 129:23-130:4.)
`
`Because of these innumerable variables, and the inherent unpredictability in this
`
`field, the impact of modifications to order of combination, chemistries employed,
`
`or filler blends used, for example, cannot be so easily presumed or predicted as
`
`Petitioner suggests. (EX2017 at 125:23-126:19; 129:23-130:4.) None of the cited
`
`references alone or in combination teaches all of the elements of any challenged
`
`claim of the ’623 patent. Patentability should be confirmed.
`
`II. Background of the Invention
`
`
`A.
`
`State of the art prior to the ’623 patent
`
`
`
`Despite Petitioner’s efforts to characterize the state of the art of papermaking
`
`as fully developed, and relatively unchanged from the methods employed in
`
`
`
`4
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`

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`ancient China, the reality is that the science of papermaking in 20081 remained
`
`complex and uncertain. (EX2017 at 48:19-49:21.) In the 2007 edition of
`
`Papermaking Chemistry, for example, it was noted that “[t]he wet end chemistry of
`
`a paper machine is very complex.” (EX1009-0028.) It was also known that
`
`multiple factors could influence interactions between chemical additives and
`
`papermaking materials, including: “i) surface properties of solid materials,
`
`ii) properties of chemical additives, iii) the chemical environment, and
`
`iv) hydrodynamical conditions.” (EX1009-0028.) And that “[k]inetic aspects also
`
`have to be considered.” (EX1009-0028.)
`
`Petitioner’s declarant, Dr. Dyer, agreed, noting there are hundreds of
`
`variables in the wet end of a paper machine: “You know, it’s the wet end of a
`
`paper machine. As we talked about, there are hundreds of variables.” (EX2017 at
`
`108:12-14; see also 125:23-126:19; 129:23-130:4.) Dr. Dyer further testified that
`
`one must look at the entire wet end process in order to optimize it, including at the
`
`type of filler being used: “So you have to look at the whole wet end of the paper
`
`machine to understand how to optimize it. And that includes what type of filler
`
`you’re using.” (EX2017 at 161:11-14.) Because of these innumerable variables,
`
`and the complexity of the system, persons of skill in the art could not easily
`
`1 The application from which the ’623 patent is a continuation in part was filed on
`
`November 26, 2008, which is the relevant priority date.
`
`
`
`5
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`

`

`determine how even small changes in one part of the system might impact other
`
`parts of the process. (EX2018 ¶ 37.)
`
`One understanding shared by those of skill in the art was that it was
`
`important to enhance the fiber-fiber bonds in order to improve paper strength.
`
`(EX2018 ¶ 32.) As a result, various interventions being tried in the industry at that
`
`time sought to strengthen these bonds. (EX1004-0006.) One way of increasing the
`
`strength of the fiber-fiber bonds was through use of various strength aids. Much
`
`research was conducted into types of strength aids and how they could improve
`
`paper strength. (EX2018 ¶ 30.) However, because the purpose of strength aids was
`
`to enhance fiber-fiber bonds, persons of skill in the art understood the importance
`
`of adding the strength aid to the cellulose fiber slurry before adding filler, not after:
`
`Q: And so if your goal was to ensure that the strength aid would work
`at its optimal capacity to bind fiber to fiber, wouldn’t you want to add
`the strength aid before you add the filler? . . .
`A: Yes, I think that’s -- you know, that’s a reasonable assumption.
`
`(EX2017 at 170:14-21; see also 170:24-171:9; EX2018 ¶ 33.) Addition of filler
`
`was understood to negatively impact fiber-fiber bonds. (EX2018 ¶ 31.)
`
`Moreover, while there was an understanding that charges within a
`
`papermaking system were important, there was no certainty of understanding about
`
`how various charges within the system would impact other aspects of the system.
`
`(EX2018 ¶ 38.) Dr. Dyer admitted all he could conclude about the likely result of
`
`
`
`6
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`

`

`introducing positively charged filler to negatively charged fiber slurry is that
`
`certain outcomes were “within the realm of possibility”:
`
`Q: So you don’t know any more -- You cannot say that it would be
`anything more than possible that the positively charged filler would
`tend to bind to the negatively charged particle, fiber particles? . . .
`A: Yes, what you said. It’s within the realm of possibility that those
`two materials would -- or those two particles would be attracted to one
`another and bind.
`(EX2017 at 167:6-16; see also 166:8-167:5; 168:15-169:8.) Papermaking is a
`
`much more nuanced system than Petitioner suggests. The suggestion that one of
`
`skill in the art could have predicted the outcome of various combinations of the
`
`cited references is undermined by Petitioner’s own declarant’s testimony.
`
`
`
`Finally, the state of the art as of the ’623 patent’s priority date encouraged
`
`use of chemistries, materials, and methods designed to cause the different
`
`constituents in the system to adhere to, and not repel, each other. (EX2018 ¶¶ 34,
`
`35; EX1009-0022.) For example, filler treatments were designed to create filler
`
`agglomeration, producing larger filler and polymer agglomerates, which are more
`
`easily retained in the paper sheet. (EX2018 ¶ 36; EX1012-0039, -0040.) Strength
`
`and drainage additives were similarly designed to encourage various components,
`
`which otherwise naturally repelled each other, to have better adherence by
`
`cancelling out repulsive forces. (EX1009-0022 (“Since most papermaking
`
`additives in water also form a negatively charged colloidal system, the different
`7
`
`
`
`

`

`constituents in the system repel each other. For this reason, to obtain acceptable
`
`retention, the colloidal repulsive forces have to be cancelled by suitable
`
`means . . . .”).) Before the ’623 patent, persons of skill in the art were not
`
`motivated to employ a process using additives designed to do the opposite—
`
`namely, encouraging different components to repel each other, whether through
`
`charge-charge interactions or otherwise.
`
`B.
`The invention of the ’623 patent
`The inventors of the ’623 patent broke with conventional wisdom, and the
`
`direction of the prior art, and conceived a method of papermaking that produced
`
`unexpected, synergistic results between a pretreated filler and later-added strength
`
`aid. In a preferred embodiment, the invention of the ’623 patent treats a filler blend
`
`by wholly or partially coating filler particles with a composition of matter designed
`
`to repel a later-added strength aid through a charge-charge interaction; combining
`
`the treated filler with the cellulose fiber slurry; and then adding a strength aid
`
`carrying the same charge as the composition of matter. (EX1001 at col. 2:53-57;
`
`col. 4:46-56; col. 6:45-50.) Employing this novel process, the inventors of the ’623
`
`patent achieved significantly better paper strength than was achieved by filler
`
`treatment or strength aid alone.
`
`The ’623 patent contains three independent claims: claims 1, 18, and 19.
`
`(EX1001 at col. 8:64-col. 9:13; col. 10:25-55; EX2018 ¶¶ 16-18.) These claims
`
`
`
`8
`
`

`

`have the following elements in common: (1) pretreatment of filler with a
`
`composition of matter in the absence of cellulose fiber stock; (2) combining the
`
`pretreated filler and the cellulose fiber stock; (3) treating the combination of the
`
`pretreated filler and fiber with a strength and/or drainage additive; to (4) achieve a
`
`specific objective. (EX1001 at col. 8:64-col. 9:13, col. 10:25-55; EX2018 ¶ 39.)
`
`Each of these claims therefore requires first filler pretreatment, second addition of
`
`the pretreated filler to the fiber, and third addition of the papermaking additive.
`
`Each independent claim also requires a specific interaction between the
`
`composition of matter used to pretreat the filler and the strength or drainage aid,
`
`which is added later in the process—after the pretreated filler and cellulose fiber
`
`stock have been combined. (EX2018 ¶ 40.) In claim 1, the composition of matter
`
`“enhances the performance of the wet strength aid or wet web strength additive or
`
`drainage additive in the paper mat.” (EX1001 at col. 9:11-13.) In claim 18, the
`
`“composition of matter enhances the performance of the dry strength aid in the
`
`paper mat.” (EX1001 at col. 10:39-40.) And, in claim 19, “the composition of
`
`matter inhibits the drainage additive or the wet web strength additive or wet
`
`strength aid from adhering to the filler particles.” (EX1001 at col. 10:53-55.)
`
`
`
`Some claims have additional distinctive features. (EX2018 ¶ 41.) For
`
`example, claim 1 additionally requires that a blend of filler particles be employed
`
`that contains at least 10% each of precipitated calcium carbonate (PCC) and
`
`
`
`9
`
`

`

`ground calcium carbonate (GCC). (EX1001 at col. 9:7-9.) And claim 16, which
`
`depends from claim 1, requires all of the above, and further specifies ensuring the
`
`pretreatment composition of matter and the strength or drainage aid carry the same
`
`charge. (EX1001 at col. 10:17-19.)
`
`The ’623 patent taught the papermaking industry a new approach—one in
`
`which filler could be added to fiber first, before addition of strength aid, without
`
`harming and indeed enhancing paper strength as compared to other methods.
`
`(EX1001 at col. 5:7-11; EX2017 at 170:14-21; EX2018 ¶ 42.) This can be seen, for
`
`example, in Figure 2 of the ’623 patent. At 14% ash content, simply pretreating the
`
`filler provided almost no improvement in break up time over use of an untreated
`
`filler—in other words, a break up time of about 1 minute. (EX1001 at Fig. 2;
`
`EX2017 at 111:25-112:2.) At the same ash content, adding just the strength aid
`
`with no filler pretreatment provided a break up time of approximately 11 minutes.
`
`(EX1001 at Fig. 2; EX2017 at 112:3-8.) But using the pretreated filler and the
`
`later-added strength aid resulted in a significantly extended break up time of
`
`approximately 15 minutes. (EX1001 at Fig. 2; see also Fig. 1 (also showing a
`
`synergistic improvement in the wet tensile index using a pretreated filler with a
`
`later-added strength aid); EX2017 at 112:9-12; EX2018 ¶¶ 43, 44.) Absent a
`
`synergistic effect between the pretreatment and the strength aid, when added in the
`
`
`
`10
`
`

`

`order of the invention, one of skill in the art would have expected to see at best an
`
`additive effect (i.e. 12 minutes). (EX2017 at 112:18-113:4.)
`
`This synergy is further demonstrated by the different slopes resulting from a
`
`comparison of filler pretreatment, plus strength aid, versus strength aid alone.
`
`(EX2018 ¶¶ 42-44.) As filler content increases, strength is not affected in the same
`
`way when the filler pretreatment of the invention, plus strength aid, is employed
`
`versus strength aid alone. (Id.)
`
`The synergistic effect of the claimed method of addition was unexpected.
`
`(EX2018 ¶ 42.) In the prior art, it was accepted that fillers reduced effectiveness of,
`
`or required a papermaker to use more of, a strength or drainage aid. (EX2018
`
`¶ 31.) In disclosing a method that resulted in the pretreated filler synergistically
`
`increasing the effect of the later-added strength or drainage aid, the ’623 patent
`
`provided a fresh approach that allowed for improvements of strength at filler levels
`
`that previously were not possible.
`
`C.
`Summary of the applied references
`The Board instituted review of various combinations of claims 1-8, 12, 13,
`
`and 16-19 on seven grounds. Each of the grounds for institution cites to one or
`
`more of the following four prior art references: Chung, Brown, Kimura, and
`
`Laufmann. None of these references, alone or in combination, teach or suggest all
`
`of the limitations of the challenged claims.
`
`
`
`11
`
`

`

`Chung
`1.
`Chung is directed to use of a cationic coagulant and an anionic flocculant
`
`
`
`having certain molecular weights to improve drainage and retention properties.
`
`(EX1007 col. 2:65-col. 3:9; EX2018 ¶ 45.) In the process disclosed in Chung, an
`
`untreated PCC filler is added to cellulose fiber at the stuff box (EX1007 at col.
`
`4:43-45), followed by a cationic starch strength additive, which is added before the
`
`fan pump (EX1007 at col. 4:45). Then, a low molecular weight cationic coagulant
`
`is added to the combination of cellulose fiber + untreated filler + cationic starch
`
`strength additive. (EX1007 at col. 4:59-64.) After the low molecular weight
`
`cationic coagulant is added, a high molecular weight anionic flocculant is added.
`
`(EX1007 at col. 4:64-68; EX2018 ¶ 46.)
`
`
`
`Chung does not teach or disclose pretreatment of filler. (EX1007 at col.
`
`4:43-48; EX2018 ¶ 47.) Chung does not teach a filler treatment designed to
`
`enhance performance of a later-added strength or drainage aid, or designed to repel
`
`or reduce adherence of a later-added strength or drainage aid through a charge-
`
`charge interaction or otherwise. (EX2018 ¶ 47.) Chung does not teach a filler blend
`
`containing at least 10% each of PCC and GCC. (EX2018 ¶ 50.) Like the other prior
`
`art of the time, Chung is directed to ensuring good binding of the components of
`
`the process, not to reducing the adherence among them. (EX1007 at col. 2:24-26
`
`
`
`12
`
`

`

`(“It has been discovered that precipitated calcium carbonate-cationic starch
`
`systems are useful as efficient binders . . . .”); EX2018 ¶¶ 48-49.)
`
`
`
`Brown
`2.
`Brown is not directed to a “treatment” for a filler, but rather to a method of
`
`producing a dispersed filler. (EX1014 at col. 2:49-51 (“The present invention
`
`provides a method for forming fillers for filling cellulosic products, such as paper
`
`and paper board.”).) The Brown patent is titled “Bulking and Opacifying Fillers for
`
`Cellulosic Products,” and is assigned to Columbia River Carbonates, which is a
`
`filler dispersion manufacturer. (EX2017 at 74:14-23.) The filler of Brown is made
`
`via a two-step process using a dispersing agent and an aggregating agent. (EX1014
`
`at col. 2:49-col. 3:29; col. 3:53-57; EX2018 ¶ 51.) Brown also does not teach the
`
`use of a filler blend containing at least 10% each of PCC and GCC. (EX2018 ¶ 57.)
`
`Brown has two examples (Examples 12 and 21) that discuss making paper using its
`
`aggregated filler. Both examples discuss adding treated filler to an existing mixture
`
`that already includes fiber and a strength additive. (EX1014 at col. 17:4-6; col.
`
`20:10-16; EX2018 ¶ 52.)
`
`Brown does not teach treating a filler with a composition of matter that is
`
`designed to enhance the performance of a later-added strength aid, or that is
`
`designed to repel or reduce adherence of a later-added strength aid through a
`
`charge-charge interaction or otherwise. (EX2018 ¶ 53; EX1014 at 5: 24-25 (“The
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`net charge present on the aggregated particles is lower than that of the feed
`
`material.”).) Brown is directed to increasing adherence of the filler to the fiber, not
`
`to enhancing fiber-fiber bonds. Example 21 of Brown illustrates use of a filler
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`dispersion with an anionic surface charge in conjunction with a cationic potato
`
`starch; in other words, opposite charges. (EX1014 at col. 16:67 – col. 17:6 (where
`
`SF2 had a surface charge of -11.41 µeg/g according to Table II and col. 16:15-18);
`
`EX2018 ¶ 54.)
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`Brown teaches away from use of a cationically charged filler dispersion and
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`a cationic strength aid. Example 21 of Brown tests a cationic filler dispersion
`
`called SF1, which it describes as a “currently available paper filler mineral
`
`pigment[].” (EX1014 at col. 20:6-15; EX2018 ¶ 54.) SF1 has a cationic surface
`
`charge of +42.1 µeg/g. (EX1014 at col. 13:40-43; EX2018 ¶ 55.) In evaluating
`
`drainage of the hand sheet made with SF1, Brown concludes SF1 significantly
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`harmed drainage:
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`The cationic product SF1 significantly retarded the
`drainage of the fiber web relative to the well draining
`rhombohedral, low surface area anionically dispersed
`pigment, Microna S-80B.
`
`(EX1014 at col. 20:18-21; EX2018 ¶ 56.) In discussing retention, Brown teaches
`
`that SF1 does not perform as well as the “products of this invention” SF2, SF3,
`
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`SF4, and SF5, which all have an anionic surface charge. (EX1014 at col. 20:29-34;
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`col. 19:8-12.)
`
`Kimura
`3.
`Kimura describes treatment of filler with a polyion complex made up of an
`
`anionic polysaccharide and a cationic or amphoteric acrylamide copolymer.
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`Kimura refers to this polyion complex as a “composite PAM.” (EX1012-0038;
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`EX2018 ¶ 58.) Both the anionic and cationic components of the polyion are needed
`
`to achieve the benefits of the invention; the benefits cannot be obtained from an
`
`individual treating agent alone. (EX1012-0038, -0067.)
`
`Kimura teaches that treatment of filler with the composite PAM results in
`
`(1) an appropriate aggregation effect and (2) a high affinity for the pulp slurry.
`
`(EX1012-0039, -0040.) When the treated filler is used in papermaking, Kimura
`
`discloses that it can be used in two methods: a batch method and a fractional
`
`method. (EX1012-0047; EX2018 ¶ 60.) In the batch method, the strength aid and
`
`sizing agent are added to the pulp slurry and then the treated filler is added.
`
`(EX1012-0047.) In the fractional method, about 30% of the treated filler is added
`
`to the pulp slurry, then the strength aid is added, and then the remaining 70% of the
`
`treated filler is added. (Id.) Kimura does not disclose use of a filler blend
`
`containing at least 10% each of PCC and GCC. (EX2018 ¶ 61.) Kimura does not
`
`teach adding a strength aid only after the treated filler has been combined with the
`
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`cellulose fiber slurry. (EX2018 ¶ 62.) Indeed, the examples of Kimura do not
`
`contain wet strength, wet web strength, or drainage aids (required by all except
`
`claim 18) at all. (EX1012-0059 to -0062.) Kimura also does not teach treating a
`
`filler with a composition of matter that is designed to repel or reduce adhesion of a
`
`later-added strength aid through a charge-charge interaction or otherwise. (EX2018
`
`¶ 63.) Rather, the polyion complex of Kimura is designed, as the state of the art
`
`suggested, to encourage aggregation of components. (EX2018 ¶ 64; EX1012-
`
`0040.)
`
`Laufmann
`4.
`Laufmann does not teach pretreatment of filler. (EX2018 ¶ 65.) Laufmann
`
`describes a series of pilot studies but does not provide any teaching concerning the
`
`order of addition of materials. (EX1016; EX2018 ¶¶ 66, 67.) Laufmann does not
`
`teach treating a filler with a composition of matter designed to enhance the
`
`performance of a later-added strength aid, or designed to repel or reduce adhesion
`
`of a later-added strength aid through a charge-charge interaction or otherwise.
`
`(EX2018 ¶ 68.) Laufmann teaches filler blends and discloses that (1) the best filler
`
`for paper strength is not a blend, but rather is 100% GCC, and (2) when blends are
`
`introduced, the charge profile of the various fillers can cause undesirable reactions
`
`with other wet end chemicals. (EX1016-0016, -0017, -0018, -0019; EX2018 ¶ 69.)
`
`The cited references, like the prior art as a whole at the relevant time, were
`
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`all focused on generating adhesive forces within the wet end system, not on using a
`
`charge-charge repulsion to cause a treated