10414980 (B.P.A.I. Jul. 16, 2012)

Ex Parte Charkoudian

Board of Patent Appeals and InterferencesJul 16, 2012

10414980 (B.P.A.I. Jul. 16, 2012)

UNITED STATES PATENT AND TRADEMARKOFFICE 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 APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO. 10/414,980 04/16/2003 John Charkoudian MCA-580 US 8314 25182 7590 07/16/2012 EMD Millipore Corporation 290 CONCORD ROAD BILLERICA, MA 01821 EXAMINER MENON, KRISHNAN S ART UNIT PAPER NUMBER 1777 MAIL DATE DELIVERY MODE 07/16/2012 PAPER 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. PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE ____________ BEFORE THE BOARD OF PATENT APPEALS AND INTERFERENCES ____________ Ex parte JOHN CHARKOUDIAN ____________ Appeal 2010-012413 Application 10/414,980 Technology Center 1700 ____________ Before ANDREW H. METZ, CHARLES F. WARREN, and BEVERLY A. FRANKLIN, Administrative Patent Judges. METZ, Administrative Patent Judge. DECISION ON APPEAL STATEMENT OF THE CASE Appellant appeals under 35 U.S.C. § 134 from the Examiner's adverse decision finally rejecting claims 10 through 18, which are all the claims in the application. We have jurisdiction under 35 U.S.C. § 6. We AFFIRM. THE INVENTION Appellant’s invention is directed to a charge-modified ultrafiltration membrane. The claimed membrane is a composite, that is, a porous, Appeal 2010-012413 Application 10/414,980 2 crosslinked cellulose membrane sheet is supported on a porous polymeric substrate, for example, ultrahigh molecular weight polyethylene [0006]1. The porous crosslinked cellulose membrane sheet is prepared from a cellulosic polymer and a crosslinking agent [0010]. Useful crosslinking agents include a genus of epoxides [0016]. Cellulose is disclosed as a useful cellulosic polymer [0022]. Charge-modification may be conducted in a one- or two-step process and the charge-modified membranes are hydrophilic and wet upon contact with water [0014]. The claimed membranes exhibit improved structural durability compared to the unmodified cellulosic polymer membranes of the prior art and have low protein-binding characteristics [0015]. Claim 10, the only independent claim before us for our consideration, is reproduced below for a more facile understanding of Appellant’s invention. 10. A charge-modified ultrafiltration porous crosslinked cellulose membrane sheet supported on a porous polymeric substrate and wherein a charged moiety is covalently bound to a surface of said crosslinked cellulose membrane. The references of record which are being relied on as evidence of obviousness are: Perry et al. (Perry) 4,659,474 Apr. 21, 1987 Azad et al. (Azad) 5,462,867 Oct. 31, 1995 Koo et al. (Koo) US 2003/0121844A1 Jul. 3, 2003 1 We reference Appellant’s disclosure by reference to paragraph numbers from the printed application, US 2004/0206694, rather than by page and line number as in the as-filed application because both the Examiner and Appellant chose to do so. Appeal 2010-012413 Application 10/414,980 3 van Reis 7,001,550 B2 Feb. 21, 2006 THE REJECTIONS Claims 10 through 18 stand rejected under 35 U.S.C. § 103(a) as being unpatentable as the claimed subject matter would have been obvious from the combined disclosures of Azad, Perry, and/or Koo. Claims 10 through 14, 17, and 18 stand rejected under 35 U.S.C. § 103(a) as being unpatentable as the claimed subject matter would have been obvious from the combined disclosures of Perry and Koo.2 Claims 10 through 18 stand rejected under 35 U.S.C. § 103(a) as being unpatentable as the claimed subject matter would have been obvious from the combined disclosures of Azad, Perry, and/or Koo considered in light of Appellant’s disclosure of known prior art or commercially available membranes. OPINION Appellant has chosen to limit the arguments in his Brief solely to the Examiner’s rejection of the claim 10. Appellant has not directed our attention to any specific limitation in any of the dependent claims that render those dependent claims patentable beyond the argued patentability of claim 10. Accordingly, we have limited our consideration to the patentability of 2 Whether the rejection before us is considered to be Perry in view of Koo or vice versa is merely a matter of presentation with no legal significance. In re Bush, 296 F.2d 491, 496 (CCPA 1961); In re Krammes, 314 F.2d 813, 816- 17 (CCPA 1963). We recognize that there may be some cases in which the relevant factual determinations inhere in such characterization of the references but this case is not one. Appeal 2010-012413 Application 10/414,980 4 claim 10 and the patentability of claims 11 through 18 stands or falls with the patentability of claim 10. We begin our review of the rejections by analyzing claim 10 to determine its scope. Claim 10 recites that the charge-modified, ultrafiltration porous crosslinked membrane is cellulose, is in the form of a sheet and is supported on a porous polymeric substrate. Claim 10 requires that the charged moiety of the charge-modified crosslinked cellulose membrane sheet is covalently bound to “a” surface of the crosslinked cellulose membrane. Thus, the charged moieties may be covalently bound to any portion of the surface of the crosslinked cellulose membrane sheet. Accordingly, we read claim 10 as encompassing a composite structure comprising at least two layers: one layer being the underlying porous polymeric sheet support; and, the second layer being the charged crosslinked cellulose membrane sheet. Beyond the membrane’s effective pore size, the limitation in claim 10 that the composite membrane sheet is an “ultrafiltration” membrane does not denote any particular structure which otherwise further distinguishes or limits the two, positively recited components of the composite of claim 10. Appellant discloses in [0002] of the Specification that porous polymeric membranes are generally classified by their effective pore size and their retentivity. Appellant discloses that the dividing line between microporous filters and ultrafilters in terms of pore size is not an absolute, scientifically defined boundary. According to Appellant, ultrafilters have an average pore size between about 0.005 microns and about 0.05 microns. Microporous membranes have an average pore size of from between about 0.05 microns Appeal 2010-012413 Application 10/414,980 5 and 10 microns. Thus, two polymeric membranes could have the same average pore size (0.05 microns) and yet be useful for separating different size particles. Accordingly, we read the limitation that the membrane of claim 10 is an “ultrafiltration membrane” as a statement of intended use, that is, the polymeric porous membrane of claim 10 has pore sizes that make it useful in ultrafiltration for separating, for example, proteins. We have carefully considered all the evidence in the record, including the prior art on which the Examiner has relied to reject the claims, and have carefully considered Appellant’s and the Examiner’s arguments in support of their respective positions. We find that the Examiner has established a prima facie case of obviousness that Appellant has failed to rebut by persuasive argument or by the presentation of probative relevant evidence. Moreover, we find Appellant’s arguments to be founded largely on limitations not recited in the claims. Each of the Examiner’s rejections is founded on his conclusion that Appellant’s invention is directed to crosslinking a commercially available ultrafiltration membrane comprising cellulose on a microporous polyethylene support and thereafter forming a charge on the membrane by covalently binding a charged moiety to the crosslinked membrane. The basis for the Examiner’s conclusion is the disclosure in Example 1 of the application and other examples of a “composite ultrafiltration membrane comprising regenerated cellulose supported on an ultrahigh molecular weight polyethylene microporous membrane “available from Millipore Corporation . . . under the catalog designation “PLCHK.” Spec. [0036]. Appeal 2010-012413 Application 10/414,980 6 Appellant assigns as “clear error” (Br. 3,4) the Examiner’s conclusion that Appellant’s composite membrane is prepared by crosslinking a commercially available membrane described in Appellant’s specification in Example 1 as commercially available from Millipore Corporation under the designation “PLCHK.” According to Appellant, the reference in Example 1 to “PLCHK” is a reference to the ultrahigh molecular weight polyethylene support, per se, and not to the composite of cellulose supported on ultrahigh molecular weight polyethylene. Appellant makes this argument without reference to any evidence in support of the argument. We find no merit in Appellant’s argument. The plain language in Example 1 specifically characterizes the reference to “PLCHK” as a “composite ultrafiltration membrane” comprising regenerated cellulose provided on ultrahigh molecular weight polyethylene. If the cited language meant only the polyethylene support it would not be characterized as a “composite membrane.” Moreover, Appellant’s assignee and the real party in interest, the Millipore Corporation, is in the best position to resolve this issue by providing evidence of exactly what is the product described in Example 1 as “PLCHK.” There is no such evidence of record. However, the Examiner has cited a reference of record (van Ries cited by Appellant in an IDS during prosecution) as evidence that supports the Examiner’s position that “composite regenerated cellulose” membranes were well known in the art as ultrafiltration membranes at the time Appellant made his invention. Since we agree with the Examiner’s interpretation of the language in Example 1 describing “PLCHK” and because van Ries further supports the examiner’s position we find the Examiner’s interpretation of the Appeal 2010-012413 Application 10/414,980 7 language in Example 1 to be the correct interpretation. We reject Appellant’s proffered interpretation because it does not make sense in the context of the actual language used in Example 1 to describe “PLCHK.” In an abundance of caution, we have undertaken to make a short search of the web for any evidence that might shed further light on this issue or aid us in disposing of this matter. Our search found a data sheet published on the Millipore Corporation’s website bearing a date of 2002 and entitled “Ultracel PLC Membranes.”3 Therein, on page 1, PLC membranes are described as composite membrane comprising a regenerated cellulose membrane supported on a microporous polyethylene substrate and useful for separating proteins. On page 4 of the data sheet “PLCHK” is described as having a nominal molecular weight limit in kilo Daltons of 100 and as useful for separating small viruses and viral antigens. Although we do not rely on this information for the purposes of our decision, it supports the Examiner’s position that the membrane described in Example 1 is a commercially available composite membrane comprising cellulose on a porous polyethylene support material. Appellant’s argument concerning the physical and chemical nature of the crosslinking in the claimed composite membrane is neither reflected by nor recited in the language of claim 10 and is not supported by any evidence in the record. Appellant’s argument that the charged moieties occur throughout the cellulose sheet is contrary to the plain language of claim 10 (“wherein a charged moiety is covalently bound to a surface of said crosslinked cellulose membrane”). We also find unpersuasive Appellant’s 3 Copy provided with this decision. Appeal 2010-012413 Application 10/414,980 8 argument that the Examiner “implies that all polysaccharides are similar.” (Br. 5). To the contrary, the Examiner has cited and relied on specific prior art (Perry and Koo, for example) for the purpose of showing that the skilled routineer in this art would have been motivated to use cellulose as the cellulosic polymer in Azad in place of the specific cellulosic polymers described by Azad as exemplary. Likewise, Appellant’s argument (Br. 7, 8) that the claimed ultrafiltration membrane sheet intrudes to a small amount into the underlying porous support finds no basis in the evidence in this record or the language of claim 10. Additionally, there is neither any evidence in the record that establishes that the crosslinked cellulosic sheet of Azad does not “intrude” into the underlying support described therein. Appellant’s reliance on the “evidence” set forth in the Evidence Appendix to his Brief as Figures 1 and 2 does not overcome the Examiner’s rejections. The Figures were submitted by Appellant on March 31, 2008 in response to the Examiner’s office action of December 6, 2007. The Figures were described in Appellant’s response as “drawings” which illustrate alleged differences between the claimed membrane (Figure 2) and the membrane described by Azad (Figure 1). The drawings were not obtained by any scientifically recognized analytical method and are not actual photographs of the actual structure of the membranes set forth in either Azad or Appellant’s Specification. Thus, because who prepared the drawings and on what basis the drawings were determined to have the structure as set forth are not established the drawings are, at best, considered to be aids to attorney argument. Appeal 2010-012413 Application 10/414,980 9 The scanning electron microscope (SEM) “picture” relied on in Appellant’s Brief as “evidence” was filed by Appellant on January 16, 2007 in response to the Examiner’s Office action of October 31, 2006. On page 3 of Appellant’s response the SEM picture was described as showing “the cross-sectional structure of a composite cellulose UF membrane of the sort used in the examples of the present application.” (emphasis added). Appellant has not established that the SEM photograph represents any particular example from the Specification but that it is only representative of a membrane “of the sort” used in the examples. What example is represented, how the sample whose SEM photograph was taken was prepared and under what conditions it was prepared are not set forth. Thus, the “picture” is not a SEM photograph of any particular example in the application but is, at best, an SEM photograph of an unidentified membrane said to be representative of the claimed membrane. Accordingly, Appellant’s conclusion that “[t]he presence of an ultrafiltration membrane sheet supported on a polyethylene microporous support is readily apparent” (Br. 10) is manifestly erroneous. The SEM photograph simply lacks authentication and sufficient identification to be considered probative on the issue for which it was proffered. We also reject Appellant’s argument that Azad is directed to microporous membranes not ultrafiltration membranes and is, therefore, not relevant to the claimed ultrafiltration membrane. As correctly noted by the Examiner (Ans. 6), Azad discloses that membranes disclosed therein have a wide range of microfiltration and ultrafiltration applications. Thus, Azad is not limited to microfiltration membranes as argued. We find Azad to be Appeal 2010-012413 Application 10/414,980 10 evidence that at the time Appellant made his invention it was known in the art to modify a polymer or structural surface of membranes useful as ultrafiltration membranes by reacting hydroxyl functionality with epoxides to crosslink the membrane and/or bind charged moieties to the membrane. Appellant concedes that Azad teaches crosslinking at page 6 of his Brief. We also find Koo and Perry to be evidence that it was known at the time Appellant made his invention that porous polymeric substrates useful as filtration membranes can be surface-modified by crosslinking cellulose and cellulosic polymers with various epoxides. Each of the references also recognizes the range of pore sizes known in the art to yield membranes with utility for separating specific compounds based on their pore size. Thus, we find that by simply starting with a membrane having a pore size suitable for the intended application, including ultrafiltration membranes specifically disclosed by each of the references, a person of ordinary skill would have been motivated to modify the properties of the membrane using the epoxide crosslinking agents of the prior art to obtain improved strength and improved ability to separate molecules as taught by the references. The decision of the Examiner 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)(1)(iv). AFFIRMED cc: cam Appeal 2010-012413 Application 10/414,980 11 Appeal 2010-012413 Application 10/414,980 12 Appeal 2010-012413 Application 10/414,980 13 Appeal 2010-012413 Application 10/414,980 14