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 .
Priority
Applicant’s claim for the benefit of a prior-filed application (371 of PCT/AU2021/050635, filed 06/18/2021) 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 (AU2020902089, filed 06/23/2020) 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 14 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) 1-3, 6, 8, 9, 12, and 13 is/are rejected under 35 U.S.C. 103 as being unpatentable over ICHINOSE et al. (JP 5880813 B2; machine translation provided and referenced herein) in view of KIM et al. (Polymer Journal, Vol. 25, No. 12, pg. 1295-1302, 19 May 1993) and further in view of HAN (US 2019/0344222 A1).
Regarding Claim 1, ICHINOSE discloses a composite filtration filter 11 (FIG. 1A, B) comprising a polyvinyl alcohol (PVA) porous membrane 21 on a supporting porous filter 31 (i.e., [a] membrane comprising a… hydrophilic layer supported on a porous… substrate; pg. 4, paragraph “(7) In the step…”; pg. 5, paragraph “Embodiment of the Present Invention”). It is noted that PVA is a highly hydrophilic material; hence the limitation requiring a hydrophilic layer is inherently disclosed. The PVA porous membrane 21 has thickness 10 nm to 500 nm (pg. 4, paragraph “The PVA porous film…”), which overlaps with the claimed range of between about 100 nm and 700 nm and therefore, establishes a case of prima facie obviousness (MPEP 2144.05) and comprises pores having diameters 1 nm to 10 nm (i.e., a nanoporous…layer), which reads on the claimed range of a pore size of the nanoporous hydrophilic layer is less than about 10 nm (pg. 4, paragraph “The PVA porous film…”). ICHINOSE further discloses the supporting porous filter 31 comprises polytetrafluoroethylene, which is inherently hydrophobic (i.e., a porous hydrophobic substrate; pg. 4, paragraph “(7) In the step…”).
The PVA porous membrane 21 is further crosslinked by a crosslinking agent (i.e., the nanoporous huydrophilic layer comprises… a crosslinking agent; pg. 4, paragraph “(7) In the step…”; pg. 6, paragraph “PVA may be crosslinked…”). In one embodiment, ICHINOSE discloses mixing 0.5 mL of a 1 wt% aqueous solution of PVA with 0.5 mL of a 2 wt% glutaraldehyde solution to prepare a glutaraldehyde-crosslinked-PVA porous membrane (pg. 11, paragraph “Example 3”). However, ICHINOSE fails to disclose any final content of glutaraldehyde in the formed PVA membrane, i.e., the prior art is deficient in explicitly disclosing a content of the crosslinking agent is between about 5% and 20% by weight of the nanoporous hydrophilic layer.
KIM discloses the effects of degree of crosslinking on the properties of polyvinyl alcohol membranes, namely the effect of glutaraldehyde degree of crosslinking on PVA hydrophilicity (e.g., contact angle), swelling, and pervaporation (abstract). While KIM is deficient in explicitly disclosing a crosslinking weight % relative to PVA weight, KIM discloses the degree of crosslinking is calculated from glutaraldehyde concentrations (paragraph spanning pg. 1299-1300). KIM states that “[w]hile crosslinkages enhance the stability of PVA membrane toward water, the selectivity factor and permeate flux decrease with increasing degree of crosslinking. Therefore, the degree of crosslinking should be optimized to prepare a pervaporation PVA membrane with good stability and pervaporation characteristics” (pg. 1302, col. 1, par. 1). Indeed, as shown in FIG. 4, with increasing degree of crosslinking, KIM reports a “decreasing of the selectivity factor and permeate flux” correlated with degree of swelling for water (pg. 1301). The claimed parameter is recognized as a result-effective variable as taught by the prior art and can be optimized through routine experimentation (MPEP §2144.05 II B). Thus, the claimed range of a content of the crosslinking agent being between about 5% and 20% by weight of the nanoporous hydrophilic layer would have been obvious to one skilled in the art at the time of the invention as taught by KIM for the PVA membrane taught by ICHINOSE.
Modified ICHINOSE is deficient in explicitly disclosing the nanoporous hydrophilic layer further comprises a nanofiller selected from the group consisting of MXene, a carbon-based nanomaterial, a MOF, and a silica nanoparticle.
HAN discloses composite nanofiltration membrane (abstract; p0003) comprising a functional layer made of MXene (p0006) with a supporting layer under the functional layer (p0005). The use of MXene as part of the functional layer advantageously provides improved long-term stability (p0003), excellent separation performance, thermal resistance, and chemical resistance (p0016). Thus, prior to the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to include MXene as a nanofiller as taught by HAN in the PVA functional layer of the composite filtration filter taught by ICHINOSE.
Regarding Claim 2, modified ICHINOSE makes obvious the membrane of Claim 1. As noted in the examples, ICHINOSE discloses formation of the PVA filter from a 1 mg/mL PVA aqueous solution (pg. 10, middle) indicating that the amount of hydrophilic polymer in the formed PVA filter is primarily the polymer (see also Table 1 on pg. 30). ICHINOSE further discloses the use of crosslinkers (e.g., 2 wt.% glutaraldehyde; pg. 14) in preparing the PVA filter. Thus, the claimed range of wherein the content of the hydrophilic polymer in the nanoporous hydrophilic layer is between about 50% and 99% by weight of the nanoporous hydrophilic layer is read upon by the prior art.
Regarding Claim 3, modified ICHINOSE makes obvious the membrane of Claim 2. ICHINOSE discloses polyvinyl alcohol (i.e., wherein the hydrophilic polymer is polyvinyl alcohol; abstract).
Regarding Claim 6, modified ICHINOSE makes obvious the membrane of Claim 1. ICHINOSE further discloses the use of glutaraldehyde crosslinker (i.e., wherein the crosslinking agent is… glutaraldehyde; pg. 5, middle).
Regarding Claim 8, modified ICHINOSE makes obvious the membrane of Claim 1. HAN further discloses MXene is Ti3C2Tx where T is –F or –OH (p0002); such a disclosure reads on the claimed formula for MXene.
Regarding Claim 9, modified ICHINOSE makes obvious the membrane of Claim 1. HAN further discloses an MXene concentration of 1-5 wt.% (p0013), which reads on the claimed range of between 0.1% and 30% by weight of the nanoporous hydrophilic layer.
Regarding Claim 12, modified ICHINOSE makes obvious the membrane of Claim 1. ICHINOSE further discloses the supporting porous filter 31 comprises polytetrafluoroethylene (i.e., wherein the porous hydrophobic substrate comprises a polymeric material selected from… polytetrafluoroethylene; pg. 4, bottom).
Regarding Claim 13, modified ICHINOSE makes obvious the membrane of Claim 1. ICHINOSE further discloses the porous material used for filter 31 comprises pore diameters ranging from “several nm to several µm” (pg. 5, paragraph “A wide range of…”), which overlaps with the claimed range of between 0.1 µm and 5 µm and therefore, establishes a case of prima facie obviousness (MPEP 2144.05).
Response to Amendments/Arguments
Applicant’s amendments and arguments filed 14 October 2025 have been fully considered.
Regarding Claim 13, the Examiner regretfully inadvertently omitted addressing Claim 13 in the prior Office action and appreciates Applicant’s careful review and gracious notice (pg. 7, middle); it is noted that the limitations of Claim 13 are directed toward the hydrophobic substrate—these limitations are taught or suggested by ICHINOSE and would have been rejected under the same grounds presented in the previous Office action as the rejection of independent Claim 1 under 35 U.S.C. 103 as being unpatentable over ICHINOSE et al. (JP 5880813 B2) in view of HAN (US 2019/0344222 A1). The introduction of KIM as a new prior art in the present Office action is to address the as-revised Claim 1 with respect to limitations unrelated to the hydrophobic substrate, i.e., crosslinking agent weight percentage.
Regarding the objections of Claims 1, 14-17, 26, 27, 29, 31, and 33, Applicant’s amendments have been fully considered and are persuasive; these objections have been withdrawn.
Regarding the rejections of Claims 5 and 6 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 5 and amendment to Claim 6 are persuasive; these rejections have been withdrawn.
Regarding the rejections of Claim(s) 1-3, 5, 6, 8, 9, and 12 under 35 U.S.C. 103 as being unpatentable over ICHINOSE et al. (JP 5880813 B2) in view of HAN (US 2019/0344222 A1), Applicant’s amendments are persuasive; these rejections have been withdrawn. However, upon further consideration and search, new grounds of rejection have been made for Claim(s) 1-3, 6, 8, 9, 12, and 13 under 35 U.S.C. 103 as being unpatentable over ICHINOSE et al. (JP 5880813 B2) in view of KIM et al. (Polymer Journal, Vol. 25, No. 12, pg. 1295-1302, 19 May 1993) and further in view of HAN (US 2019/0344222 A1).
Regarding the rejections of Claim(s) 1-3, 5, 6, 8, 9, and 12 under 35 U.S.C. 103 as being unpatentable over ICHINOSE et al. (JP 5880813 B2) in view of HAN (US 2019/0344222 A1), Applicant’s arguments (pg. 8-10) have been fully considered.
Applicant argues that the as-amended Claim 1 now reciting that a content of the crosslinking agent is between about 5% and 20% by weight of the nanoporous hydrophilic layer is not recited by the prior art (pg. 9, top);
Applicant further argues that
“this concentration range contributes to the unexpected results obtained with membranes according to the pending claims”;
further, such a claimed crosslinking agent range provides for “a crosslinking density that stabilizes the nanoporous structure and introduces facilitated transport sites, which markedly improve flux performance while maintaining selectivity”; and
“the skilled artisan would not expect, with any reasonable expectation of success, to achieve these performance benefits from the proffered combination of Ichinose (which uses a crosslinker at much lower levels), with Han (which is silent on crosslinking levels)” (pg. 9, middle).
The Examiner respectfully disagrees.
Regarding (1) and (2)c, Applicant’s arguments are directed to grounds of rejection that have been withdrawn. Therefore, these arguments are not commensurate in scope with the presently pending claims.
Regarding (2)a and (2)b, the Examiner appreciates Applicant’s evidence shown in Example 1, paragraph 0121, and paragraph 0152 of the published application. However, such results are not unexpected as shown by KIM. KIM finds that the degree of crosslinking by glutaraldehyde of PVA affects the degree of swelling of a PVA membrane and thereby stability, selectivity, and permeate flux/pervaporative characteristics. KIM explicitly states “[t]he degree of crosslinking should be optimized to prepare a pervaporation PVA membrane with good stability and pervaporation characteristics” (pg. 1302, col. 1, par. 1)”. Crosslinking agent weight %, which is correlated with degree of crosslinking, is therefore recognized as a result-effective variable as taught by the prior art and can be optimized through routine experimentation (MPEP §2144.05 II B).
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, In Suk Bullock can be reached at 571-272-5954. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/Ryan B Huang/Primary Examiner, Art Unit 1777