UNITED STATES PATENT AND TRADEMARK OFFICE
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`BEFORE THE PATENT TRIAL AND APPEAL BOARD
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`GUANGDONG ALISON HI-TECH CO., LTD.,
`Petitioner
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`v.
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`ASPEN AEROGELS, INC.,
`Patent Owner
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`Case IPR2017-00152
`Patent 7,780,890
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`PATENT OWNER ASPEN AEROGELS, INC.’S
`PRELIMINARY RESPONSE
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`B. 
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`Case IPR2017-00152
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`TABLE OF CONTENTS
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`i
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`INTRODUCTION .............................................................................................................. 1 
`THE ’890 PATENT ............................................................................................................ 2 
`CLAIM CONSTRUCTION .............................................................................................. 11 
`A. 
`“Gel sheet(s)” (claims 11, 13, 18) ......................................................................... 12 
`B. 
`“Continuous sheet” (claim 11) .............................................................................. 14 
`C. 
`“Sol” (claims 11, 15, 17, 21)................................................................................. 15 
`D. 
`“Rolling the dispensed sheet into a plurality of layers” (claim 11) ...................... 16 
`E. 
`“The layers” (claim 11) ......................................................................................... 17 
`PETITIONER’S INVALIDITY GROUNDS SHOULD BE REJECTED ....................... 17 
`Grounds 1-3: Claims 11-13, 15, 17, and 21 are not rendered obvious by the
`A. 
`combination of Nakanishi and any one of Ramamurthi, Roberts, or Andersen ... 18 
`Nakanishi does not disclose “A method for preparing gel sheets”
`1. 
`comprising the step of “dispensing a sol onto a moving element as a
`continuous sheet,” as recited in claim 11 .................................................. 18 
`The Rolling and Drying Prior Art combined with Nakanishi does not
`render claim 11 obvious ............................................................................ 28 
`Dependent claims 12, 13, 15, 17, and 21 .................................................. 40 
`3. 
`Grounds 4-5: Claims 11-13, 15, 17, and 21 are not obvious over Ramamurthi in
`view of either Nakanishi or Champagne ............................................................... 41 
`Ground 4: Neither Ramamurthi nor Nakanishi discloses “dispensing a sol
`1. 
`onto a moving element as a continuous sheet,” “rolling the dispensed sheet
`into a plurality of layers,” or “drying the layers” ...................................... 41 
`Ground 5: Ramamurthi and Champagne do not render obvious claims 11-
`13, 15, 17, or 21 ........................................................................................ 45 
`Ground 6: Claims 11-13, 15, 17, and 21 are not rendered obvious by the
`combination of Sonoda and Uchida ...................................................................... 50 
`Neither Sonoda nor Uchida discloses “dispensing a sol onto a moving
`1. 
`element as a continuous sheet” ................................................................. 50 
`Neither Sonoda nor Uchida discloses “rolling the dispensed sheet into a
`plurality of layers” .................................................................................... 56 
`Sonoda does not disclose “drying the layers” ........................................... 58 
`Dependent claims 12, 13, 15, 17, and 21 .................................................. 58 
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`2. 
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`2. 
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`2. 
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`3. 
`4. 
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`E. 
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`D. 
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`Grounds 7 and 8: Claims 18 and 19 are not rendered obvious over Nakanishi in
`view of Ramamurthi and either Chew or Leeke ................................................... 59 
`Ground 9-12: Claims 18 and 19 are not rendered obvious over Ramamurthi in
`view of Champagne and either Chew or Leeke, and Sonoda in View of Uchida
`and either Chew or Leeke ..................................................................................... 62 
`PETITIONER’S ASSERTED GROUNDS ARE HIGHLY REDUNDANT ................... 63 
`CONCLUSION ................................................................................................................. 65 
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`ii
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`Case IPR2017-00152
`Attorney Docket No: 41577-0003IP1
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`LIST OF EXHIBITS
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`Exhibit No. Description
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`AA 2001
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`Aspen’s 6th Supplemental Response to Nano 1st Set of
`Interrogatory No. 43 (Oct. 3, 2016)
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`AA 2002
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`Press Release: Aspen Aerogels Receives Title III Funding to Build
`High Technology Manufacturing Facility in Rhode Island
`(ASPEN0040124-ASPEN0040126) (Sept. 17, 2004)
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`AA 2003
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`Frank ’075 – U.S. Pat. No. 5,789,075
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`AA 2004
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`Fricke, et al., Optimization of Monolithic Silica Aerogel Insulants
`(ASPEN0040127-40131), April 18, 1991
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`AA 2005
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`RESERVED
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`AA 2006
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`RESERVED
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`AA 2007
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`Fidler – U.S. Pat. No. 6,136,216
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`AA 2008
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`Brinker & Scherer, Sol-Gel Science: The Physics and Chemistry of
`Sol-Gel Processing (Academic Press, Inc. 1990)
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`AA 2009
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`Encyclopedia Britannica Online re gel electrophoresis
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`AA 2010
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`Bouis – U.S. Pat. No. 6,203,679
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`AA 2011
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`Declaration by Dr. George L. Gould and Appendices A & B
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`AA 2012
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`Wikipedia: “Sol-Gel” https://en.wikipedia.org/wiki/Sol-gel
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`AA 2013
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`Order No. 35: Construing Certain Terms of the Asserted Claims of
`the Patents at Issue (Markman Claim Construction), In the Matter
`of Certain Composite Aerogel Insulation Materials and Methods
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`iii
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`for Manufacturing the Same, Inv. No. 337-TA-1003, USITC (Jan.
`31, 2017)
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`AA 2014
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`McGraw-Hill Dictionary of Scientific and Technical Terms, Sixth
`ed., 2003.
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`INTRODUCTION
`The ’890 patent relates to a process for manufacturing a little-known but
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`very important substance known as aerogel—a near perfect insulator that has
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`myriad commercial applications. Before the ’890 patent, aerogel had little
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`practical applicability primarily due to limitations on the size of aerogel sheets that
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`could be produced. The ’890 patent overcame that problem by providing a process
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`that allowed the manufacture of arbitrarily long aerogel sheets. Commercially
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`implementing this groundbreaking process caused Patent Owner’s revenue to
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`increase more than 1,000-fold. (Ex. 2001 at 12-13.) And because this previously
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`unavailable ability to produce arbitrarily long sheets of aerogel was considered
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`important to national security, the U.S. Government set aside funds to help pay for
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`the factory that uses this inventive process to produce aerogel sheets. (Ex. 2002.)
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`It was truly a pioneering invention.
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`Ignoring that reality, Petitioner uses hindsight to cobble together various
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`references in a failed effort to meet its burden. However, none of the combinations
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`asserted in the Petition renders obvious the invention at issue. For example, the
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`cited art—regardless of how it is combined—fails to disclose or suggest either
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`dispensing a sol onto a moving element as a continuous sheet, or rolling that
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`continuous gel sheet into a plurality of layers, as required by the sole challenged
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`independent claim.
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`1
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`The Encyclopedia Britannica graphic illustrating a “tape-casting” process at
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`page 7 of the Petition (Ex. 1018) is ironically representative of the deficiencies of
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`Petitioner’s asserted grounds (ironic because Petitioner bothers to include it in the
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`Petition but, knowing that it is irrelevant, declines to include it in any of the
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`asserted grounds). Among other failures, the depicted tape-casting process (a)
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`does not relate to sol-gels in general or aerogels in particular, (b) does not dispense
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`a sol onto a moving element as a continuous sheet, and (c) does not dry a sheet
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`rolled into a plurality of layers. Petitioner’s inclusion of this graphic is an attempt
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`to mislead the Board into believing that the ’890 patent claims something other
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`than the ground-breaking invention that it does.1
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`For these and other reasons set forth below, the Board should decline to
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`institute IPR.
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` THE ’890 PATENT
`Aerogel is a very lightweight material that has incredible insulating
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`properties. Due to its ethereal appearance (shown below), aerogel is sometimes
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` 1
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` Petitioner makes a misleading representation in the Petition at page 6 by asserting
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`that the graphic shows “rolling” occurring before “drying” (as recited in claim 11)
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`when in fact it shows the exact opposite. Dr. Scherer’s declaration makes the same
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`blatant misrepresentation. Ex. 1018, ¶ 24.
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`referred to as “frozen smoke” or “solid smoke.” It was first created in the 1930s,
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`but had limited commercial applicability for 70 or so years until the’890 patent.
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`To form an aerogel, a low-viscosity colloidal suspension comprising gel
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`precursor material and a solvent (together known as sol) is induced or catalyzed to
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`turn into a gel. Such gels have a liquid phase interspersed within a solid phase
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`having a three-dimensional porous lattice structure. The liquid portion of the gel is
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`then extracted from the pores of the solid gel structure—usually under extreme
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`conditions such as very high temperature and pressure—without appreciably
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`degrading the three-dimensional lattice structure. This leaves behind an aerogel,
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`i.e., a solid three-dimensional lattice structure filled predominantly with air (rather
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`than the extracted liquid). (See ’890, 1:23-26 (“Aerogels describe a class of
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`material based upon their structure, namely low density, open cell structures, large
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`surface areas (often 900 m2/g or higher) and sub-nanometer scale pore sizes.”).)
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`In manufacturing aerogel, the sol formation and gelling conditions must be
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`carefully designed and executed to allow for the formation of a low-density gel,
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`which can then be processed into low-density aerogel. Accomplishing the delicate
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`chemistry of forming low density gels from a sol under industrial conditions is
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`relatively difficult compared to other, more robust polymers and gels that are easy
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`to optimize for industrial processing.
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`Aerogels have excellent insulating performance. (See, e.g., ’890, 1:37
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`(describing aerogels as “the best solid thermal insulators”); Ex. 1006, 1:33-38
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`(stating that aerogels are “extremely valuable” for “insulation”).) Heat transfer by
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`convection is reduced because aerogels are almost entirely air, and heat transfer by
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`conduction is reduced because the lattice structure inhibits it. (’890, 1:36-45.)
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`Heat transfer by radiation also can be reduced by including opacifiers or other
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`opaque components in the aerogel. (Id. at 7:67-8:3.)
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`Aerogels by themselves are fragile and brittle, and will generally fall apart if
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`flexed or bent. For example, the gel sheets disclosed in the ’890 patent are
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`ordinarily stiff, inflexible and fragile—absent fiber reinforcement. (See, e.g., ’890,
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`1:26-28 (noting the “fragile cells of the material”), 5:32-35 (“these gel materials
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`are normally stiff and inflexible when they are composed of a ceramic or cross-
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`linked polymer matrix material with intercalated solvent (gel solvent) in the
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`absence of fiber reinforcement”); Frank ’075 (Ex. 2003), 1:63-67 (noting the “great
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`brittleness of prior art aerogels”).) These mechanical properties traditionally have
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`impeded the use of aerogels as insulators in many real-world scenarios. In the
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`decades since aerogels were first discovered in the 1930s, researchers have been
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`looking for ways to make aerogels suitable for real-world applications by
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`combining them with other, more durable materials. Aspen, the Patent Owner,
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`ultimately solved this problem with its pioneering composite aerogels that combine
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`aerogels with certain fibrous materials, and its processes for manufacturing them.
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`Aspen’s composite aerogel blankets are used in a variety of insulating applications
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`ranging from NASA projects, to deep ocean oil pipes, to commercial and
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`residential building insulation.
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`The ’890 patent, titled “Methods to produce gel sheets,” is directed to novel
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`methods for manufacturing composite aerogel insulation materials in arbitrarily
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`long sheets or rolls. Before the patent, relatively small sheets of aerogel were
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`formed via a process known as “batch casting.” (’890, 2:4-9.) The patent
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`explains, “Batch casting is defined here as catalyzing one entire volume of sol to
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`induce gelation simultaneously throughout that volume.” (’890, 2:7-9.) In batch
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`casting, the gel precursor and solvent, together called “sol,” are placed into a mold
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`along with the batting and catalyzed to form a gel essentially simultaneously
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`throughout the entire volume of the mold. The liquid portion of the gel can then be
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`removed via prior art methods, leaving behind the aerogel composite in the mold.
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`Batch casting suffered a number of shortcomings. For example, the size of
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`the mold limited the size of the resulting aerogel sheet. As a result, sheets of
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`aerogel having any desired arbitrary length—e.g., several hundred feet—could not
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`feasibly be produced. For example, the size of the sheets described in Ramamurthi
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`(issued in 1994) is just 12 inches by 12 inches. (Ex. 1006, 12:36-49.) And, in
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`1991, almost six decades after the invention of aerogels, researchers noted that
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`“monolithic aerogel tiles of sizes up to 40 x 40 x 2 cm3… are available in small
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`quantities.” (Ex. 2004 (Fricke) (emphasis added).) Notably, Fricke described the
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`state of the art approximately 60 years after scientists began working with aerogel.
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`Consequently, because of this manufacturing limitation, several potential
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`applications for aerogel such as insulating pipelines went unrealized.
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`Another drawback of batch casting was that gelation of the entire sheet
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`occurred all at once. Such simultaneous gelation resulted from the fact that the
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`entire volume of sol in a batch cast needed to be simultaneously combined with the
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`catalyst so that the entire volume of sol would have the same gelation profile. As a
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`result, due to the low mechanical strength of gels, the gel could not be bent or
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`rolled into multiple layers without cracking or breaking. And because a batch-
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`casted gel sheet could not be rolled into multiple layers, it was further size limited
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`in that it could not be longer than the size of the dryer into which the gel sheet
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`must be placed and treated as the final step in the aerogel manufacturing process.
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`Consequently, the longest aerogel sheet that could be produced using a batch
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`casting technique was about 16 feet. See Ex. 2011, ¶¶ 5, 34 (Decl. of Dr. George
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`L. Gould).
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`In addition, batch casting was known to be difficult and time-consuming.
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`See, e.g., Ex. 1006, 1:42-44 (“Monolithic aerogels prepared using [conventional]
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`techniques disclosed in the literature are fragile and the preparation process
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`involves complex time-consuming steps.”).
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`In comparison to batch casting, the ’890 patent’s continuous process allows
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`for much longer gel sheets (e.g., 200 feet or longer) and improved manufacturing
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`efficiencies. (’890, 3:60-4:4.) As disclosed in the ’890 patent, Patent Owner’s
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`novel method for manufacturing aerogels involves allowing an aerogel material to
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`be created “continuously or semi-continuously” (’890, 3:56-4:5) using one or more
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`conveyer belts, as shown below in annotated Figure 1 of the patent:
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`Liquid
`sol
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`Gel-inducing agent (i.e., catalyst)
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`Mixer
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`Rolling
`assembly
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`Roll of
`fibrous
`batting
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`Conveyor belt
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`As shown above, a roll of fibrous batting (17) is unrolled at one end of one or more
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`conveyor belts (18). (’890, 9:23-39.) Liquid sol (11) and a gel-inducing agent, or
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`“catalyst” (12), are mixed together by mixer (14) to form a low-viscosity
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`“catalyzed sol,” which is flowed onto the fibrous batting sheet (17). As the liquid-
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`impregnated batting moves along the conveyor belt(s), the catalyst (12) in the
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`mixture causes the liquid sol to gradually turn into a solid gel structure, with the
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`batting fibers interspersed within and around the gel structure. At the far end of
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`the belts, the fiber-reinforced gel sheet, which has now sufficiently strengthened to
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`be rolled but not allowed to become so stiff that it would crack while being rolled,
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`is wound into a roll (19). The strength (and, as a result, degree of stiffness) of the
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`sheet at the point it reaches the rolling assembly (19) is controlled by various
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`variables, including the speed of the conveyor belt, the length of the conveyor, and
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`the chemical composition of the catalyzed sol.
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`Optional additional processing steps may then be performed, such as aging
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`(setting the sheet aside for a time to allow the gel to further strengthen). The sheet
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`can then be dried to extract the liquid phase of the gel, leaving behind a composite
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`aerogel insulation material in a roll form. Unlike in the prior art processes, “[v]ery
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`long continuous sheets of fiber-reinforced, flexible gel material are readily
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`fashioned using the methods of this invention because … the combined casting and
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`rolling process[] allows a single molding surface to be continuously re-utilized
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`within a small production area.” (’890, 3:62-67.)
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`The ’890 patent explains that, due to the nature of aerogels, several variables
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`must be taken into account for the method to work properly. For one, “all
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`components are fed into the apparatus at the appropriate rate.” (’890, 3:57-58.)
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`Also, the sol must be dispensed “at a predetermined rate effective to allow gelation
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`to occur on the moving element.” (’890, 2:39-41.) And, because the sol dispensed
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`onto the conveyor is of “low viscosity,” and because “gel formation” occurs on the
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`conveyor (’890, 2:35-41), the speed and length of the conveyor belt are important.
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`(See, e.g., ’890, 10:46-50 (describing an embodiment “where sol is dispensed onto
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`a convey[o]r belt and allowed to gel as the convey[o]r belt travels a specific
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`distance (corresponding to a specified residence time) and rolled onto a
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`mandrel”).) Winding the gel into a roll occurs at a post-gelation “residence time,”
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`which includes sufficient time for full gelation and an optimized amount of aging
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`such that the gel is sufficiently firm to avoid seeping (or breaking), while
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`remaining sufficiently flexible to be rolled. (’890, 11:49-53.) In other words,
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`unlike batch casting in which gelation of the entire sheet occurred simultaneously,
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`in the process claimed in the ’890 patent, the continuous gel sheet undergoes
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`gradual gelation as it moves along the conveyor belt (18). (See ’890, 2:40-41.) At
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`the point it reaches the rolling assembly (19), the gel is both sufficiently strong
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`enough to be rolled while remaining sufficiently flexible to enable the continuous
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`sheet to be rolled into multiple layers without cracking or breaking. (See ’890,
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`5:57-61, 11:62-12:3.) As explained above, if the entire continuous sheet were
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`allowed to completely gel all at once—such as occurs with batch casting—it would
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`tend to crack or break if rolling it into multiple layers were attempted. (See, e.g.,
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`Ex. 2007, Fidler, 1:43-45 (“[A]erogel is brittle, non-flexible and when compressed
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`it fractures. As a result, aerogel can’t be flexed during use. An attempt to
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`compress or flex large pieces of it will result in breaking them.”).)
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`Petitioner challenges the validity of independent claim 11, and seven of its
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`dependent claims—12, 13, 15, 17, 18, 19, and 21 (“the challenged claims”).
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`Petitioner’s challenges are based on a hindsight-inspired hodgepodge of highly
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`redundant references that it lumps together into three different categories:
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`“Conveyor Prior Art,” “Rolling and Drying Prior Art,” and “Spacer Prior Art.”
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`Petitioner does not even attempt to argue that the references within any one group
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`have meaningful differences from one another, and therefore essentially admits
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`their redundancy. And the manner in which Petitioner breaks down the references
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`into three convenient constituents (Conveyor, Rolling and Drying, Spacer), and
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`then arbitrarily stitches them together using the challenged claims as a roadmap,
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`makes clear that Petitioner is doing nothing more than applying hindsight
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`reconstruction. More importantly, even in applying hindsight, Petitioner’s
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`proposed combinations fail to disclose or suggest several limitations of the
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`challenged claims, as explained below.
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` CLAIM CONSTRUCTION
`For purposes of this IPR, Patent Owner proposes the following claim
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`constructions. All other claim terms are to be given their “broadest reasonable
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`construction in light of the specification of the patent in which it appears.” 37
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`C.F.R. § 42.100(b).2
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` 2
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` The claim construction order of the Administrative Law Judge at the International
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`Trade Commission is attached as Ex. 2013.
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`A.
`“Gel sheet(s)” (claims 11, 13, 18)
`The term “gel sheets” (or “gel sheet”) appears in the preamble of claim 11
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`(“A process for preparing gel sheets ….”), and in the body of claims 13 and 18,
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`which depend from claim 11. It should be interpreted to mean “gel sheets suitable
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`for manufacturing aerogel products.” Several reasons support this construction.
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`First, the preamble of claim 11 is limiting. “[T[erms appearing in a
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`preamble may be deemed limitations of a claim when they give meaning to the
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`claim and properly define the invention.” In re Paulsen, 30 F.3d 1475, 1479 (Fed.
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`Cir. 1994). Further, “[t]he effect preamble language should be given can be
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`resolved only on review of the entirety of the patent to gain an understanding of
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`what the inventors actually invented and intended to encompass by the claim.”
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`Corning Glass Works v. Sumitomo Elec. U.S.A., Inc., 868 F.2d 1251, 1257 (Fed.
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`Cir. 1989). Here, the preamble, including the term “gel sheets,” was intended to be
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`encompassed by claim 11. Indeed, as reflected in claims 13 and 18, the dependent
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`claims acknowledge—and further describe—the “gel sheet” component of the
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`invention. The ’890 patent’s title indicates what the inventors actually invented,
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`namely, “Advanced gel sheet production.” And in its first sentence, the patent
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`states that the “present invention provides various methods for producing gel
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`sheets in a continuous fashion.” (’890, Abstract (emphasis added).) In addition,
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`“gel sheets” is the portion of the claim that makes clear the nature of the recited
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`“dispensed sheet.” The specification likewise states that “dispensing the catalyzed
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`sol at a predetermined rate effective to allow gelation to occur on the moving
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`element” results in a “formed gel sheet.” (’890, 2:35-41 (also explaining that the
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`catalyst “induces gel formation and form[s] a gel sheet on a moving element”).);
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`see Corning Glass Works, 868 F.2d at 1257 (preamble phrase “an optical
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`waveguide” limited claims to optical fibers, because “[t]he invention is restricted
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`to those fibers that work as waveguides as defined in the specification, which is not
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`true with respect to fibers constructed with the limitations of the [body of the
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`claim] only”). The specification consistently reiterates that it regards methods for
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`producing gel sheets, and that limitation, accordingly is part of claim 11. (See,
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`e.g., ’890, 1:17-18 (“[The] invention relates to the preparation of solvent filled gel
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`sheets ….”), 2:34-38 (“[T]he invention describes … forming a gel sheet ….”),
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`2:53-54 (“[T]he methods describe the formation of monolithic gel sheets ….”).)
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`Second, the term “gel sheets” means “gel sheets suitable for manufacturing
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`aerogel products.” In that regard, the patent explains that the gel sheets are limited
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`to those used to produce aerogel products. According to the patent, gel sheets
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`produced according to its methods “are used in manufacturing aerogel blankets
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`used in a variety of applications including thermal and acoustic insulation.” (’890,
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`Abstract.) The specification further explains, “This invention relates to the
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`preparation of solvent filled gel sheets in a continuous fashion. Such gel sheets are
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`used in manufacturing aerogel blankets, aerogel composites, aerogel monoliths
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`Case IPR2017-00152
`Attorney Docket No: 41577-0003IP1
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`and other aerogel based products.” (’890, 1:17-21 (emphasis added).) In other
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`words, the sole purpose of the gel sheets produced by the method of claim 11 is to
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`create aerogel products.
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`Accordingly, the “gel sheets,” which are “prepar[ed]” according to the
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`“process” of the challenged claims, are “gel sheets suitable for manufacturing
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`aerogel products.”
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`B.
`“Continuous sheet” (claim 11)
`The term “continuous sheet” means “a gel sheet formed by a process that
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`can continue indefinitely to produce a sheet of any arbitrary length.” The ’890
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`patent explains that the gel sheets are monolithic in nature and formed
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`continuously on a conveyor belt by a continuous process. For example, the patent
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`describes its methods “for producing gel sheets in a continuous fashion.” (’890,
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`Abstract (emphasis added); 2:52-60 (“Even more specifically, the methods
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`describe the formation of monolithic gel sheets or fiber-reinforced gel composite
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`… in a continuous or semi-continuous fashion.” (emphasis added)).) The patent
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`explains: “Very long continuous sheets of fiber-reinforced, flexible gel material
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`are readily fashioned using the methods of this invention ….” (’890, 3:62-65.)
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`The patent places no limit on length of the continuous sheet, instead describing
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`that, under the proper belt speed, “such that the gelation front within the mixed sol
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`(defined as the fixed position along the conveyor table at which the sol is no longer
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`Case IPR2017-00152
`Attorney Docket No: 41577-0003IP1
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`free flowing, taking on a rubbery quality) appears halfway along the length of the
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`table,” the flexible gel composite can be “rolled into a plurality of layers,” such as
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`indicated by the rolling assembly 19 in Fig. 1. (’890, 3:40, 11:20-24.) Thus, with
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`the proper adjustments, the process can continue indefinitely to make arbitrarily
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`long sheets.
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`C.
`“Sol” (claims 11, 15, 17, 21)
`The term “sol” means “a low-viscosity colloidal suspension before it has
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`formed into a gel.” The patent explains at the outset that the sol is a low-viscosity
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`liquid that is mixed together with a gel-inducing catalyst, dispensed on a conveyor
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`belt, and then forms into a gel while being conveyed along. Specifically, the patent
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`states that “the invention describes methods for continuously combining a low
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`viscosity solution of a sol and an agent (heat catalyst or chemical catalyst) that
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`induces gel formation” and “dispensing the catalyzed sol at a predetermined rate
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`effective to allow gelation to occur on the moving element.” (’890, 2:34-41, 4:42
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`(referring to the “low viscosity, catalyzed sol mixture”).) The patent further
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`explains that, referring to Fig. 1, “11 is a stable sol precursor solution, 12 is a
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`catalyst to induce gelation of the sol …, 14 is a static mixer, 15 is the position in
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`the liquid mixing system wherein the sol has been mixed thoroughly with catalyst,
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`18 indicates … [conveyor apparatus] surfaces along the length of which gelation
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`occurs prior to the rolling assembly indicated by 19.” Id., 9:28-39. In addition, a
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`Case IPR2017-00152
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`POSITA would have recognized that a sol is “colloidal” and it describes a
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`suspension “before it has formed into a gel.” See, e.g., Ex. 2008 (Sol-Gel Science:
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`The Physics and Chemistry of Sol-Gel Processing) at 2 (“A sol is a colloidal
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`suspension of solid particles in a liquid.”), xi (describing “gelation of the sol”).).
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`Accordingly, a POSITA would have understood that, because gelation does
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`not occur until the mixture is moving “along the length” of the conveyor, the sol is
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`dispensed onto the moving element not as a gel, but rather as a low-viscosity
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`suspension.
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`D.
`“Rolling the dispensed sheet into a plurality of layers” (claim 11)
`The term “rolling the dispensed sheet into a plurality of layers” means
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`“rolling the sheet into a roll having at least two overlapping layers.” The patent
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`explains that gel sheets formed according to the method it describes can be “rolled
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`into a plurality of layers.” (’890, 3:38-40.) According to the patent, “this is a
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`novel and effective way of producing gel sheets for efficient drying operations” in
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`spite of the possible adhesion of gel sheet layers to each other in wet form or
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`especially upon drying. (’890, 3:40-42.) The patent depicts and describes the
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`“rolling assembly” with a continuous sheet rolling up into multiple layers. For
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`example, an annotated portion of Figure 2 of the ’890 patent depicts the rolling
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`assembly (29) (’890, 9:55):
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`Case IPR2017-00152
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`Thus, as discussed in the patent and depicted in the patent’s figures, “rolling the
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`dispensed sheet into a plurality of layers” means “rolling the sheet into a roll
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`having at least two overlapping layers.”
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`E.
`“The layers” (claim 11)
`The term “the layers” as used in claim 11 means “the plurality of layers
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`forming the rolled sheet.” This BRI follows logically from the claim language
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`itself. For example, the last two words of claim 11—“the layers”—draw their
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`antecedent support from the preceding step: “rolling the dispensed sheet into a
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`plurality of layers.” Accordingly, the only plausible reading of “the layers” is that
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`it refers to “the plurality of layers” that together form the rolled sheet.
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` PETITIONER’S INVALIDITY GROUNDS SHOULD BE REJECTED
`Petitioner does not allege that any single reference is anticipatory. Instead,
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`Petitioner relies on a highly redundant patchwork of prior art combinations in an
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`attempt to establish that the ’890 patent would have been obvious. Each of the
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`Grounds Petitioner puts forth fails.
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`Case IPR2017-00152
`Attorney Docket No: 41577-0003IP1
`A. Grounds 1-3: Claims 11-13, 15, 17, and 21 are not rendered
`obvious by the combination of Nakanishi and any one of
`Ramamurthi, Roberts, or Andersen
`1.
`Nakanishi does not disclose “A method for preparing gel
`sheets” comprising the step of “dispensing a sol onto a
`moving element as a continuous sheet,” as recited in claim
`11
`Claim 11 recites several limitations not found in Nakanishi. For example, as
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`explained below, Petitioner has failed to establish that Nakanishi discloses either a
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`“method for preparing gel sheets” or “dispensing a sol,” much less dispensing that
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`sol “onto a moving element as a continuous sheet,” as required by claim 11.
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`a)
`“gel sheets”
`As explained above, claim 11 recites a method for preparing “gel sheets,”
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`i.e., “gel sheets suitable for manufacturing aerogel products.” The patent explains
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`that the “sol” of claim 11 is a component of a “low viscosity solution of a sol and
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`an agent (heat catalyst or chemical catalyst) that induces gel formation.” (’890,
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`2:35-37.) Claim 11’s method uses the sol to prepare “gel sheets”—and,
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`specifically, aerogel sheets (after supercritical drying). As the patent explains, the
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`gel sheets are for “aerogel based products.” (See, e.g., ’890, 1:18-21 (“This
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`invention relates to the preparation of solvent filled gel sheets in a continuous
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`fashion. Such gel sheets are used in manufacturing aerogel blankets, aerogel
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`composites, aerogel monoliths and other aerogel based products.”).)
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