Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 22 OCTOBER 2025 has been entered.
Priority
Applicant’s claim for the benefit of a prior-filed application (371 of PCT/IN2020/051059, filed 26 December 2020) under 35 U.S.C. 119(e) or under 35 U.S.C. 120, 121, 365(c), or 386(c) is acknowledged.
Acknowledgment is made of applicant’s claim for foreign priority (IN201911054162, filed 27 December 2019) under 35 U.S.C. 119 (a)-(d). Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Drawings
The drawings were received on 22 October 2025. These drawings are acceptable.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim(s) 19-22 and 25-31 is/are rejected under 35 U.S.C. 103 as being unpatentable over TOMASCHKE (US 5,246,587).
Regarding Claim 19, TOMASCHKE discloses a composite membrane formed by interfacial polymerization (abstract). Briefly, a microporous support is coated with an aqueous solution comprising a monomeric polyamine reactant and a monomeric amine salt and reacted with an organic solvent solution of a monomeric amine-reactive reactant (c3/58-69). The microporous support comprises a polysulfone or a polyimide (i.e., a base layer of porous polymer support membrane, wherein the base layer of porous polymer support membrane is selected from the group consisting of hydrolyzed polyacrylonitrile (HPAN), polysulfone (PSf), polyimide, crosslinked polyimide, and polyarcrylonitrile (PAN); c4/27-31).
The polyamine reactant includes cycloaliphatic diamines, e.g., piperazine (PIP; c4/45-60). The amine-reactive reactant includes an admixture with polyfunctional aromatic acyl halides, including trimesoyl chloride (TMC; c5/29-46). TOMASCHKE further discloses that the aqueous solution contains a surfactant to improve results; surfactants include sodium dodecyl benzene sulfonate (348.8 g/mol), sodium dodecyl/laurel sulfate (288.38 g/mol) or mixtures thereof (i.e., in the presence of an anionic surfactant… in an aqueous phase) at concentrations of about 0.01 to 0.5 wt% (i.e., 0.29 mM to 14.3 mM and 0.35 mM to 17.3 mM, respectively; c7/52-60), which reads on the claimed range of an anionic surfactant at a concentration from 0.01 mM to 1 M.
Finally, the resultant polyamide layer from the interfacial polymerization of the polyamine reactant, amine salt, and amine-reactive reactant has a thickness of 0.05 to 1.0 µm (i.e., an upper polymer nanofilm layer; the upper polymer nanofilm layer is made via interfacial polymerization; c8/27-29), which overlaps with the claimed range of a thickness of the upper polymer nanofilm layer is from 7 nm to 150 nm and therefore, establishes a case of prima facie obviousness (MPEP 2144.05).
The prior art is deficient in explicitly disclosing an elemental composition (atomic %) of 71.4% to 74.8% carbon, 7.5% to 12.8% nitrogen, and 12.4% to 21.1% oxygen. However, given the same or similar claimed reaction conditions are taught by the prior art, such claimed elemental compositions are inherent and necessarily expected. “[T]he fact that a characteristic is a necessary feature or result of a prior-art embodiment (that is itself sufficiently described and enabled) is enough for inherent anticipation, even if that fact was unknown at the time of the prior invention.” (Toro Co. v. Deere & Co., 355 F.3d 1313, 1320, 69 USPQ2d 1584, 1590 (Fed. Cir. 2004); MPEP §2112 II). Even further, the prior art discloses or makes obvious the same interfacial polymerization method of the same amine and acid chloride monomers (PIP and TMC, respectively) as those cited by the inventors of the claimed invention (see Table 4 on pgs. 35-36 of the Specification) wherein the aqueous phase includes an anionic surfactant, e.g. sodium laurel sulfate (pg. 15, lines 21-28; pg. 19, lines 1-6); Applicant identifies such resultant polyamides to have elemental compositions of 74.2% carbon, 9.2% nitrogen, and 16.6% oxygen (third entry in Table 4); 75.2% carbon, 12.1% nitrogen, and 12.7% oxygen (ninth entry in Table 4); and 74.3% carbon, 11.8% nitrogen, and 13.9% oxygen (tenth entry in Table 4). Thus, given the same or similar reaction conditions and reactants, the claimed elemental composition is inherently expected.
Furthermore, the limitation “the upper polymer nanofilm layer is made via interfacial polymerization…” renders the claim a product-by-process claim. Because the prior art discloses a product that appears to be the same as the product set forth in this product-by-process claim, although perhaps produced by a different process, the claim is directly read on by the prior art (see In re Marosi, 710 F.2d 799, 218 USPQ 289 (Fed. Cir. 1983) and In re Thorpe, 777 F.2d 695, 227 USPQ 964 (Fed. Cir. 1985); MPEP §2113). Additionally, although the immediate claim is a product-by-process claim and is limited by and defined by its process, the determination of patentability is based on the product itself, not on the method of production. Thus, these process limitations do not further limit the claimed product.
Regarding Claim 20, TOMASCHKE makes obvious the composite membrane of Claim 19. TOMASCHKE further discloses the composite membrane includes a polyamide layer (i.e., the upper polymer nanofilm layer is selected from the group consisting of polyamide…; c8/26-27).
Regarding Claims 21, 22, and 25-30, TOMASCHKE makes obvious the composite membrane of Claim 19. All recited limitations in these claims are directed toward properties (Claims 21, 22, and 25-30) or functions (Claims 25-29) inherent to the claimed composite membrane. The discovery of a previously unappreciated property of a prior art composition, or of a scientific explanation for the prior art’s functioning, does not render the old composition patentably new to the discoverer (Atlas Powder Co. v. Ireco Inc., 190 F.3d 1342, 1347, 51 USPQ2d 1943, 1947, Fed. Cir. 1999; MPEP §2112 I). Although TOMASCHKE is deficient in explicitly disclosing a zeta potential, a Young’s modulus, mass density, water contact angle, or molecular weight cut-off, such limitations are directed toward properties inherent for the claimed composite membrane. Given that TOMASCHKE discloses similar or the same process by which the composite membrane is produced, such claimed properties are inherent and necessarily expected absent additional differentiation. “[T]he fact that a characteristic is a necessary feature or result of a prior-art embodiment (that is itself sufficiently described and enabled) is enough for inherent anticipation, even if that fact was unknown at the time of the prior invention.” (Toro Co. v. Deere & Co., 355 F.3d 1313, 1320, 69 USPQ2d 1584, 1590 (Fed. Cir. 2004); MPEP §2112 II). As noted earlier, the prior art discloses or makes obvious the same interfacial polymerization method of the same amine and acid chloride monomers (PIP and TMC, respectively) as those cited by the inventors of the instant application (see Table 4 on pgs. 35-36 of the Specification) wherein the aqueous phase includes an anionic surfactant, e.g. sodium laurel sulfate (pg. 15, lines 21-28; pg. 19, lines 1-6); Applicant identifies such resultant polyamide composite membranes to have the same claimed zeta potential, Young’s modulus, mass density, water contact angle, and molecular weight cut-off. Thus, given the same or similar reaction conditions and reactants, including the use of an anionic surfactant in the aqueous phase of the polymerization reaction, these instantly claimed properties are inherently expected and would be obvious in the composite membrane suggested by TOMASCHKE.
Furthermore, the claim limitations of pure water permeance, Na2SO4, NaCl, and MgCl2 rejection rates, ideal salt selectivities between NaCl and Na2SO4 and between NaCl and MgCl2, and ion selectivity between monovalent and divalent anions are directed toward manners or methods by which the claimed composite membrane is used and are not subject to patentable weight. The manner or method in which an apparatus is to be utilized is not subject to the issue of patentability of the apparatus itself (In re Casey, 370 F.2d 576, 152 USPQ 235 (CCPA 1967); MPEP §2115).
Response to 37 CFR 1.132 Affidavit
The declaration under 37 CFR 1.132 filed 22 October 2025 is sufficient to overcome the rejection of claim 19 based upon 35 U.S.C. 103 as being unpatentable over WANG et al. (Nature Communications, 9, Article number 2004, published 21 May 2018) in view of MANSOURPANAH et al. (Journal of Membrane Science 343, 2009, 219-228) as set forth in the last Office action. Declarant’s arguments regarding MANSOURPANAH’s teaching of anionic surfactants in the organic phase instead of the aqueous phase as claimed (see ¶3-4) is persuasive. Regarding the Office Action’s assertion of inherency with respect to zeta potential (see ¶9), Declarant’s arguments are persuasive. It is acknowledged that WANG and MANSOURPANAH disclose a sufficiently different process by which the composite membrane is produced and as such, a membrane produced or suggested by that process would not be obvious to one of ordinary skill in the art to inherently possess the claimed zeta potential values.
Response to Amendments/Arguments
Applicant’s amendments and arguments filed 22 October 2025 have been fully considered.
Regarding the rejection of Claim 23 under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite, Applicant’s cancellation of Claim 23 has rendered the rejection moot and withdrawn.
Regarding the rejections of Claim(s) 19-23 and 25-31 under 35 U.S.C. 103 as being unpatentable over WANG et al. (Nature Communications, 9, Article number 2004, published 21 May 2018) in view of MANSOURPANAH et al. (Journal of Membrane Science 343, 2009, 219-228), Applicant’s amendments and arguments, specifically the arguments presented in the affidavit filed 22 October 2025, are persuasive; these rejections have been withdrawn. See §Response to 37 CFR 1.132 Affidavit. However, upon further search and consideration, new grounds of rejection have been made for Claim(s) 19-22 and 25-31 under 35 U.S.C. 103 as being unpatentable over TOMASCHKE (US 5,246,587) in view of ZHANG et al. (US 2014/0054228 A1).
Applicant’s arguments summarized Dr. KARAN’s declaration, which the Examiner has indicated was persuasive to merit withdrawal of the previous prior art rejections. However, Applicant’s arguments have been considered but are not persuasive because they are directed to grounds of rejection that have been withdrawn. Therefore, the arguments are not commensurate in scope with the presently pending claims.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
ZHANG et al. (US 2014/0054228 A1): ZHANG discloses nanofiltration membranes comprising thin-film polyamide composite membranes with a porous substrate and a coating layer (p0020). The substrate is further comprised of polysulfones or polyimides (p0021). The coating layer is prepared from interfacial polymerization of piperazine (p0023) and trimesoyl chloride (p0024). ZHANG further reports a zeta potential versus pH of the membranes ranging from about -16 to about -20 mV at pH 7 (FIG. 5).
MATSUI et al. (US 2018/0001274 A1): MATSUI discloses a composite semipermeable membrane comprising a polyamide skin layer obtained by interfacial polymerization and supported by a porous support (p0043; p0058). The polyamide layer contains a polymer of piperazine and trimesic acid chloride (p0049, p0055) at a thickness of 0.05 to 2 µm (p0078); and the porous support comprises polyimides or polysulfones (p0057). The resulting Young’s Modulus/elastic modulus of the skin layer is 150 MPa or more (p0082).
TAKAGI et al. (US 2015/0298064 A1): TAKAGI discloses a polyamide separation functional layer of a composite membrane (prepared by interfacial condensation of an amine and an acid halide; p0056) supported on a porous support containing polysulfone (p0053). An elasticity modulus between 0.1 GPa and 5.0 GPa is disclosed and is advantageous for water desalination in that flow resistance is reduced when elasticity is 0.1 GPa or more and membrane integrity is maintained below 5.0 GPa (p0100).
DENNISON et al. (ACS Applied Nano Materials, 2018, 1, 5008-5018): DENNISON discloses thin film composite polyamide membranes comprising 100 nm thick polyamide active layers (§Introduction, pg. 5008, par. 1). Mass densities for such TFC membranes are as high as 2 g/cm3 but are also commercially available at 1.2±0.1 g/cm3 (§Introduction, pg. 5009, par. 1). As noted, control of active layer mass density determines membrane performance, e.g., as polyamide film density increases, water uptake and water flux decline (§Introduction, pg. 5008, par. 2).
YABUNO et al. (US 2021/0101119 A1): YABUNO discloses a composite semipermeable membrane comprising a polyamide polymer (p0009) on a supporting layer (p0018). YABUNO further discloses water contact angles for the composite membrane.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to RYAN B HUANG whose telephone number is (571)270-0327. The examiner can normally be reached 9 am-5 pm EST.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, In Suk Bullock can be reached on 571-272-5954. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/Ryan B Huang/Primary Examiner, Art Unit 1777
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