Ex Parte Gawryla et alDownload PDFPatent Trial and Appeal BoardMay 9, 201813377574 (P.T.A.B. May. 9, 2018) Copy Citation UNITED STA TES p A TENT AND TRADEMARK OFFICE APPLICATION NO. FILING DATE 13/377,574 12/12/2011 23908 7590 05/11/2018 RENNER OTTO BOISSELLE & SKLAR, LLP 1621 EUCLID AVENUE NINETEENTH FLOOR CLEVELAND, OH 44115 FIRST NAMED INVENTOR Matthew D. Gawryla UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O. Box 1450 Alexandria, Virginia 22313-1450 www .uspto.gov ATTORNEY DOCKET NO. CONFIRMATION NO. AEROPOl 02WOUS 5285 EXAMINER ZEMEL, IRINA SOPJIA ART UNIT PAPER NUMBER 1765 NOTIFICATION DATE DELIVERY MODE 05/11/2018 ELECTRONIC Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the following e-mail address( es): ipdocket@rennerotto.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte MATTHEW D. GA WRYLA and DAVID A. SCHIRALDI Appeal2016-005274 Application 13/377,574 Technology Center 1700 Before MARK NAGUMO, JAMES C. HOUSEL, and N. WHITNEY WILSON, Administrative Patent Judges. HOUSEL, Administrative Patent Judge. DECISION ON APPEAL 1 Pursuant to 35 U.S.C. § 134(a), Appellants2 appeal from the Examiner's decision rejecting claims 1-5 and 7-16. We have jurisdiction over the appeal under 35 U.S.C. § 6(b). We AFFIRM. 1 Our decision refers to the Specification (Spec.) filed December 12, 2011, the Examiner's Non-Final Office Action (Non-Final) dated April 22, 2014, Appellants' Appeal Brief (Appeal Br.) filed October 19, 2015, the Examiner's Answer (Ans.) dated February 16, 2016, and Appellants' Reply Brief (Reply Br.) filed April 18, 2016. 2 According to Appellants, the real party in interest is Case W estem Reserve University. Appeal Br. 2. Appeal2016-005274 Application 13/377,574 STATEMENT OF THE CASE The invention relates to a method for preparing aerogels by subjecting an aerogel precursor to a freeze/thaw cycle prior to freeze drying (Spec. 1, Technical Field). According to Appellants, subjecting the aerogel precursor to a freeze/thaw cycle prior to freeze drying improves the compressive strength of the resulting aerogel (id. at 4:3-10). Appellants disclose that highly porous aerogels and aerogel-like structures include a three-dimensional, open-cell body formed using two- phase systems, including dispersions, emulsions, solutions, suspensions, and latexes (id. at 4:27-30). The aerogel may be polymer based, and may be formed solely from one or more polymers in combination with a dispersion medium, or clays, additives, fillers, fibers, etc. may be combined with the polymer and dispersion to form the aerogel (id. at 4:20-26). Appellants further disclose that "[t]he polymer used in the aerogel may be one or more monomers, polymers, copolymers, or combinations thereof' (Spec. 5:8-9). For the dispersion medium, Appellants disclose "any suitable liquid compound or mixture of compounds that forms a crystalline phase structure when frozen and is sublimable" may be used, and may be a solvent that dissolves the polymer (id. at 8:8-15). Sole independent claim 1, reproduced below from the Claims Appendix to the Appeal Brief, is illustrative of the subject matter on appeal. The limitation at issue is italicized. 1. A method of forming an aero gel, including: forming an aerogel precursor, the aerogel precursor including a matrix material and a liquid dispersion medium for dispersing the matrix material, wherein the matrix material includes a polymeric material, the polymeric material present in the aerogel precursor from about 1 wt% to about 5 wt%; 2 Appeal2016-005274 Application 13/377,574 performing at least two freeze/thaw cycles on the aerogel precursor, each freeze/thaw cycle including: freezing the aerogel precursor so that the dispersion is solidified; and thawing the aerogel precursor to liquefy the frozen dispersion medium; freezing the aerogel precursor after performing the at least two freeze/thaw cycles so that the dispersion is solidified; and freeze drying the aerogel precursor to sublime the dispersion medium and form the aerogel. REJECTIONS The Examiner maintains, and Appellants request our review of, the following grounds of rejection under 35 U.S.C. § 103(a): 1. Claims 1-5 and 7-14 as unpatentable over Schiraldi 3 in view of any one of Stauffer, 4 Peppas, 5 and Urushizaki; 6 2. Claim 15 as unpatentable over Schiraldi and any one of Stauffer, Peppas, and Urushizaki, further in view of Loeb; 7 and 3. Claim 16 as unpatentable over Schiraldi and any one of Stauffer, Peppas, and Urushizaki, further in view of Woerpel. 8 3 US 2008/0132632 Al, published June 5, 2008 ("Schiraldi"). 4 Shauna R. Stauffer and Nikolaos A. Peppas, Poly(vinyl alcohol) Hydrogels Prepared by Freeze-Thawing Cyclic Processing, 33 POLYMER, No. 18, 3932-3936 (1992) ("Stauffer"). 5 Nikolaos A. Peppas and Jill E. Scott, Controlled Release From Poly(vinyl alcohol) Gels Prepared by Freeze-Thawing Processes, 18 J. CONTROLLED RELEASE 95-100 (1992) ("Peppas"). 6 Fumio Urushizaki, et al., Swelling and Mechanical Properties of Poly(vinyl alcohol) Hydrogels, 58 INT'L J. PHARMACEUTICS 135-142 (1990) ("Urushizaki"). 7 US 4,059,970, issued November 29, 1977 ("Loeb"). 8 US 4,200,228, issued April 29, 1980 ("Woerpel"). 3 Appeal2016-005274 Application 13/377,574 ANALYSIS Appellants argue neither the claims nor the rejections separately, instead focusing solely on the rejection of claim 1. Accordingly, we limit our review of Appellants' arguments to claim 1. Remaining claims 2-5 and 7-16 stand or fall therewith. 37 C.F.R. § 41.37(c)(l)(iv) (2015). After review of the opposing positions articulated by Appellants and the Examiner and the evidence of obviousness adduced by the Examiner in light of the countervailing Declaration evidence proffered by Appellants, we determine that the Appellants' arguments and evidence are insufficient to outweigh the evidence of obviousness marshalled by the Examiner. Thus, Appellants have not identified reversible error in the Examiner's obviousness rejection of claim 1. In re Jung, 637 F.3d 1356, 1365 (Fed. Cir. 2011 ). Accordingly, we affirm the stated obviousness rejections for substantially the fact findings and the reasons set forth by the Examiner in record before us. We offer the following for emphasis only. The following facts are not in dispute (compare Non-Final 2-3 with Appeal Br. 6-7; see also Ans. 3): Schiraldi discloses a method for forming an aerogel from a precursor including poly( vinyl alcohol) ("PVOH") as recited in claim 1 except for the at least two freeze/thaw cycles. Stauffer, Peppas, and Urushizaki each disclose preparing hydrogels from a precursor including PVOH in an aqueous dispersion medium using a plurality of freeze/thaw cycles, wherein the resulting hydro gels have improved mechanical strength. Stauffer's precursor includes 10-15 wt% 4 Appeal2016-005274 Application 13/377,574 PVOH, whereas Peppas' and Urushizaki's precursor each includes 15 wt% PVOH. Based on these facts, the Examiner concludes that it would have been obvious to modify Schiraldi' s method for forming an aero gel to include several freeze/thaw cycles to obtain gels with improved properties as taught by Stauffer, Peppas, and Urushizaki (Non-Final 3). Appellants argue that the Declaration under 37 C.F.R. § 1.132 of Dr. David A. Schiraldi ("Schiraldi Declaration" or "Dec.") filed February 13, 2015 establishes that there was no reason to expect that freeze/thaw cycling an aerogel precursor, particularly at "relatively low polymer concentrations (i.e., 1 wt% to 5 wt%)" would have provided any advantage (Appeal Br. 4). In this regard, Appellants contend the Schiraldi Declaration states that it was expected that thawing a frozen aerogel precursor would result in the loss of any structure formed by the polymer and/or clays, fillers, and additives during freezing (id.; see also id. at 9). According to Appellants, this expectation is consistent with the thermodynamic law of entropy, "which requires that a system return to its most randomized state in the absence of applied forces" (id.). Therefore, Appellants contend that freeze/thawing of an aerogel precursor "was conventionally viewed as a meaningless exercise" (id.). In light of the conventional view, Appellants urge that they unexpectedly found that freeze-thaw cycling the aerogel precursor allows for the number of domains of crystals in which the layers are oriented in the same direction to increase while also decreasing in their respective sizes. It was quite surprising that the aerogel precursor, despite the relatively low polymer concentration, maintained a localized structural memory when subjected to freeze-thaw cycling (which in-tum lead to the increased number of the domains). 5 Appeal2016-005274 Application 13/377,574 Id. at 5. In addition, Appellants assert that aerogels formed using freeze/thaw cycling have improved compressive strength over aero gels formed without such freeze/thaw cycling (id.). Appellants further argue that each of Stauffer, Peppas, and Urushizaki describes the formation of a hydrogel, not an aerogel (Appeal Br. 7). Appellants characterize a hydrogel as a colloidal gel in which water is dispersed and retained in a polymer network (matrix), whereas an aerogel is a solid, highly porous, and low density material (id.; see also Reply Br. 2-3). Appellants assert that the polymer concentration of a hydrogel precursor is typically high, e.g., above 10 wt%, as compared with the polymer concentration in an aerogel precursor, e.g., about 1 wt% to about 5 wt% as recited in claim 1 (id.). Appellants urge that they fail to see how the teachings of the secondary references using higher polymer concentrations could be extrapolated to any precursor polymer concentration (id. at 11; see also Reply Br. 5---6). Appellants contend, therefore, that there would have been no rational basis to modify Schiraldi' s aero gel production method in view of the hydro gel production processes of Stauffer, Peppas, and Urushizaki (id. at 8). These arguments are not persuasive of reversible error in the appealed rejection of claim 1. The Examiner's rejection merely extends the teaching of the secondary references beyond the PVOH concentration range taught therein, but within the range taught in Schiraldi. In re Sernaker, 702 F .2d 989, 994 (Fed. Cir. 1983) (motivation to combine may be based on "whether a combination of the teaching of all or any of the references would have suggested (expressly or by implication) the possibility of achieving further improvement by combining such teachings along the line of the invention in 6 Appeal2016-005274 Application 13/377,574 suit"). Moreover, "[i]t is well established that a determination of obviousness based on teachings from multiple references does not require an actual, physical substitution of elements." In re Mouttet, 686 F.3d 1322, 1332 (Fed. Cir. 2012) (citing In re Etter, 756 F.2d 852, 859 (Fed. Cir. 1985) (en bane)); see also In re Keller, 642 F.2d 413, 425 (CCPA 1981) ("To justify combining reference teachings in support of a rejection it is not necessary that a device shown in one reference can be physically inserted into the device shown in the other" (citation omitted)). "Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art." Keller, 642 F.2d at 425 (citation omitted); see also In re McLaughlin, 443 F.2d 1392, 1395 (CCPA 1971) ("the test for combining references is not what the individual references themselves suggest but rather what the combination of disclosures taken as a whole would suggest to one of ordinary skill in the art."). Initially, we note the Schiraldi Declaration states that the conventional view was that freeze/thaw cycling would be a meaningless exercise because it was thought that the precursor would return to its pre-frozen state upon thawing, particularly at low polymer concentrations. However, Declarant fails to explain satisfactorily why the teachings of Stauffer, Peppas, and Urushizaki would have been expected to fail at about 5 wt% PVOH. Although each of these references using a higher polymer concentration than the range of claim 1, neither Declarant nor Appellants persuasively explain via factual evidence why the phenomena observed by Stauffer, Peppas, and Urushizaki, i.e., formation of a persistent PVOH cross-linked network or matrix after successive freeze/thaw cycling using precursors at 10-15 wt% PVOH, would not have been expected at lower concentrations such as 5 7 Appeal2016-005274 Application 13/377,574 wt% PVOH. Declarant states that, particularly in the case of relatively low polymer concentrations, the ordinary artisan would have expected the system to return to its original state when thawed after being frozen (Dec. 2). Yet, Declarant does not provide a persuasive evidentiary basis or technical reasoning in support of this statement at polymer concentrations only two to three times less than the prior art references teaching hydro gels. Neither Declarant nor Appellants direct our attention to any disclosure in any of the secondary references indicating that the observed phenomena of the building of a persistent polymer cross-linked network is limited to concentrations of 10-15 wt%. Indeed, we note Appellants disclose that the polymer concentrations in the precursor for aerogels may be about 1 to about 40 wt%, and that "[h ]igher concentrations of polymer in solution will generally produce robust structures, but will reduce the porosity and provide for higher densities" (Spec. 8:24--31 ). Appellants fail to persuade us that the ordinary artisan would not have reasonably expected freeze/thaw cycling lower polymer concentration precursors to similarly benefit from the phenomena observed by the secondary references. With regard to Appellants' attempt to contrast hydro gels from aerogels, we note that the only differences between the methods of producing the hydro gels of Stauffer, Peppas, and Urushizaki and the method of forming the aero gel of claim 1 are the different concentrations and the final freeze drying step. Urushizaki, in particular, reports that with each successive freeze/thaw cycle, more of the polymer is incorporated into the network (Urishizaki 137, col. 2, second para.). The fact that the network builds with each cycle indicates that a force is at work, which Urushizaki identifies as cross-linking of the polymer. That the degree of cross-linking 8 Appeal2016-005274 Application 13/377,574 increases indicates that the strength of inter-chain bonding is sufficient to survive the dilution that occurs in subsequent freeze-thawing cycles. Therefore, we are not persuaded that the ordinary artisan would have reasonably inferred that the persistent polymer network formed by successive freeze/thaw cycling observed by each of Stauffer, Peppas, and Urushizaki would not occur in the slightly more dilute precursor used to form an aerogel, i.e., freeze drying Schiraldi's PVOH precursor following the plural freeze-thaw cycles recommended by the secondary references. In addition, Appellants argue that the stability for a hydrogel is different than the stability associated with that of an aero gel (Appeal Br. 10). Appellants assert that stability in Schiraldi refers to that of the freeze dried aerogel, whereas the stability discussed in Stauffer, Peppas, and Urushizaki refers to the hydro gel obtained at the higher polymer concentration (id.). Appellants contend "[i]t is improper to summarily equate the different contexts in which stability is present in the references, particularly in view of the different polymer concentrations and different processes for producing the hydrogel and aerogel" (id. at 10-11). We note here that Appellants' claim 1 does not recite any properties for the resulting aerogel, much less stability. Appellants also fail to direct our attention to any evidence or persuasive technical reasoning that the stability of the resulting aero gel is an unexpected property. Notwithstanding the lack of such a showing, we note that although hydrogels and aero gels are distinct final products, the phenomena observed by the secondary references would have been reasonably expected, as discussed above, in Schiraldi' s precursor upon successive freeze/thaw cycles. As such, the ordinary artisan would likewise have reasonably expected that the resulting persistent, cross- 9 Appeal2016-005274 Application 13/377,574 linked polymer network would not only provide improved mechanical strength as recognized by the secondary references, but also would contribute greater stability in both the hydrogel and the freeze dried aerogel. Finally, we note that though Declarant and Appellants present data on the modulus (kPa) of aerogels at 2.5 and 5.0 wt% PVOH with and without freeze/thaw cycling (Dec. 3; Spec. 16), Appellants do not argue that this data would have been interpreted as evidence of an unexpected result. In re Mayne, 104 F.3d 1339, 1344 (Fed. Cir. 1997) ("Even were it obvious to a practitioner of the art, applicants have the burden to provide the PTO with evidence showing that such is the case."). Nevertheless, on this record, a preponderance of the evidence supports the determination, as discussed above, that the ordinary artisan would have reasonably expected, applying the teachings of the secondary teachings to the method of Schiraldi, that the resulting aerogel would possess improved mechanical strength as taught in the secondary references. DECISION Upon consideration of the record, and for the reasons given above and in the Non-Final Office Action of April 22, 2014 and the Examiner's Answer, the decision of the Examiner rejecting claims 1-5 and 7-23 under 35 U.S.C. § 103(a) as unpatentable over Schiraldi in view of any one of Stauffer, Peppas, and Urushizaki, alone or further in view of Loeb or W oerpel, is affirmed. No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a)(l). AFFIRMED 10 Copy with citationCopy as parenthetical citation