DETAILED ACTION
This action is in response to the amendments and remarks filed 07/08/2026, in which claims 1-21 are pending, claims 8-10 and 19-21 have been withdrawn as directed to a non-elected invention and claims 1-7 and 11-18 are ready for examination.
Information Disclosure Statement
The information disclosure statements (IDS) submitted on 08 JULY 2026 are in compliance with the provisions of 37 CFR 1.97 and have been considered. An initialed copy of Form 1449 is enclosed herewith.
Claim Interpretation
“crosslinked nanofibers and/or microfibers” is interpreted to mean the nanofibers and/or microfibers are connected together by covalent chemical bonds, as defined in the specification P8/L20-23.
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 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.
Claims 1, 3-7 and 11-12, 14, 16 and 18 are rejected under 35 U.S.C. 103 as being unpatentable over US 2017/0144107 Al (hereinafter “Garaj”) in view of US 2021/0140096 A1 (hereinafter “Zhang”) and US 2019/0062458 A1 (hereinafter “Schneiderman”).
Regarding Claim 1 Garaj discloses a graphene-based membrane which may be an ion exchange membrane [0060] and which may comprise a supporting substate [00079] (i.e. an ion-selective conduction composite membrane), having a thickness of between 10 nm to 10 micrometers [0128];
comprising a layer (considered the claimed inner layer) formed of graphene nanoparticles which may be functionalized at the surface by charged groups and/or groups which become charged in the presence of water [0060], [0063], [0066]-[0068] and having pores with a diameter of between 0.5 and 2 nm, [0072].
Since the range(s) disclosed overlaps the range(s) claimed, the range(s) recited in the claim is/are considered prima facie obvious. Overlapping ranges are prima facie evidence of obviousness. It would have been obvious to one having ordinary skill in the art to have selected the portion of the disclosed range(s) that corresponds to the claimed range. See MPEP 2144.05(I).
Garaj does not disclose said at least one inner layer, disposed between two outer layers, the outer layers are each formed of a first material comprising a network of crosslinked nanofibers and/or microfibers and pores with a diameter of between 10 nm and 10 µm
However, with regard to two outer layers, Zhang discloses a composite filtration membrane having a graphene membrane 1 which is disposed between two outer supporting layers 2, where the supporting layers function as filtration aiding layers and may be cellulose filter paper; Fig. 1, [0028], [0059], [0060].
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to modify the composite of Garaj by including two outer layers of cellulose filter paper on both sides of the graphene membrane as disclosed by Zhang because this is known means to provide support and additional filter aiding layers to a graphene membrane to enhanced filtration and support.
Garaj in view of Zhang thus discloses a functionalized graphene inner layer, disposed between two outer layers of cellulose filter paper; but does not disclose said the outer layers are each formed of a first material comprising a network of crosslinked nanofibers and/or microfibers and pores with a diameter of between 10 nm and 10 µm
However, with regard to crosslinked nanofibers and/or microfibers, Schneiderman discloses porous polymeric cellulose prepared via crosslinking cellulose nanofibers, and which can be incorporated into membranes for filtration, i.e. cellulose filtration paper (Abstract, [0039], [0056], [0066], Example 1), wherein the membrane comprising the porous crosslinked cellulose nanofibers can have higher binding capacity and can operate at higher flow rates than existing membranes [0022].
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to modify the composite of Garaj in view of Zhang by substituting for the cellulose filter paper outer layers the crosslinked cellulose nanofiber filter paper as disclosed by Schneiderman because the involves the simple substitution of known cellulose filter papers which can be incorporated into membranes to obtain the predictable result of forming a successful membrane and because the porous crosslinked cellulose nanofiber membranes can have higher binding capacity and can operate at higher flow rates than existing membranes.
With regard to the pore diameters of the outer layers, Garaj notes that additional layers used with the graphene ion exchange membrane should have a pore size that does not affect liquid flux through the graphene-based membrane [0079], and thus pore size of the outer layers is a variable which achieves a recognized result, and it would therefore have been obvious for one of skill in the art to optimize this variable through routine experimentation, by using values including those within the scope of the present claims, so as to produce desired liquid flux through the graphene-based membrane. See MPEP § 2144.05 (B).
Regarding Claim 3 Garaj in view of Zhang and Schneiderman discloses the membrane according to claim 1, wherein the nanoparticles are graphene, supra (i.e. lamellar nanoparticles).
Regarding Claim 4 Garaj in view of Zhang and Schneiderman discloses the membrane according to claim 1, wherein the ionized groups, the charged groups and/or groups which become charged in the presence of water have a negative electric charge Garaj [0058]-[0059], [0066]-[0067], [0085], [0111].
Regarding Claim 5 Garaj in view of Zhang and Schneiderman discloses the membrane according to claim 1, wherein the charged groups and/or groups which become charged in the presence of water have a positive electric charge Garaj [0058]-[0059], [0066]-[0067], [0085], [0111].
Regarding Claim 6 Garaj in view of Zhang and Schneiderman discloses the membrane according to claim 1, wherein the crosslinked nanofibers and/or microfibers are nanofibers and/or microfibers of cellulose, supra, i.e. an organic material.
Regarding Claim 7 Garaj in view of Zhang and Schneiderman discloses the membrane according to claim 1, but does not disclose wherein the crosslinked nanofibers and/or the microfibers carry at their surface charged groups and/or groups which become charged in the presence of water, said groups having a charge of the same sign as that of the charged groups and/or groups which become charged in the presence of water of the functionalized nanoparticles of the inner layer.
Further, Schneiderman discloses the cellulose nanofiber compositions may be further modified to add ion exchange functional groups to the fiber surfaces (i.e. positively or negatively charged groups) [0056], [0059], [0064], Examples 2-3.
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to modify the composite of Garaj in view of Zhang and Schneiderman by functionalizing the cellulose fibers with ion exchanges groups as disclosed by Schneiderman in order to increase ion selectivity/ion exchange capacity of the ion exchange membrane.
While the prior art does not disclose specifically using ion exchange groups of the same change, one of skill in the art would find it obvious to try using charges which are either positive or negative, because this involves choosing between a finite number of options (i.e. the charge must either be the same or opposite).
Regarding Claim 11 Garaj in view of Zhang and Schneiderman discloses the membrane according to claim 3, wherein the lamellar nanoparticles are graphene, supra (i.e. lamellar nanoparticles of carbon).
Regarding Claim 12 Garaj in view of Zhang and Schneiderman discloses the membrane according to claim 3, wherein the lamellar nanoparticles are lamellar nanoparticles of graphene oxide Garaj [0063].
Regarding Claim 14 Garaj in view of Zhang and Schneiderman discloses the membrane according to claim 4, wherein the negatively charged groups are selected from hydroxyl group, carboxyl group, sulfonate group -SO₃, Garaj [0085].
Regarding Claim 16 Garaj in view of Zhang and Schneiderman discloses the membrane according to claim 5, wherein the positive groups may be trialkylammonium groups; Garaj [0085], i.e. where a trialkyl ammonium group attached to the graphene would inherently have a Nitrogen with one bond to the graphene and three bonds to the three alkyl groups, i.e. that as claimed for a quaternary ammonium group -N(R)₃⁺ with R being a alkyl. While it is not disclosed that R is specifically a C1-C4 alkyl, it would have been obvious to try at least the most simple alkyl group i.e. methyl, for the alkyl groups, which is thus a C1 alkyl.
Regarding Claim 18 Garaj in view of Zhang and Schneiderman discloses the membrane according to claim 6, wherein the crosslinked nanofibers are nanofibers of cellulose, supra.
Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Garaj in view of Zhang and Schneiderman further in view of JP 2016137455 A (hereinafter “Takamoto”).
Regarding Claim 2 Garaj in view of Zhang and Schneiderman discloses the membrane according to claim 1, wherein the thickness of the inner layer (GO membrane) is between 10 nm and 10 µm (Garaj [0128]) but neither Zhang nor Schneiderman disclose a specific thickness of the outer layers is between 2 µm and 45 µm.
However, Takamoto discloses a similar composite ion exchange membrane having a base ion exchange membrane 1 (i.e. an inner layer) 1 disposed between two surface layers 2 (i.e. outer layers) of cellulose nanofibers on either side of the inner layer, [0006]-[0007], [0019], wherein the thickness of each surface layer may be from 1-50 micron [0035], and the thickness of the base ion exchange membrane may be from 10-500 micron [0037].
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to modify the composite of Garaj in view of Zhang and Schneiderman by forming the outer nanofiber cellulose layer to have a thickness of from 1-50 microns as disclosed by Schneiderman because this involves the simple substitution of known cellulose nanofiber outer layer thickness used in similar membrane having an inner ion exchange membrane disposed between two outer nanofiber layers to obtain the predictable result of forming a successful membrane.
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over Garaj in view of Zhang and Schneiderman further in view of US 2020/0384422 A1 (hereinafter “Liu”).
Regarding Claim 13 Garaj in view of Zhang and Schneiderman discloses the membrane according to claim 11, but does not disclose are lamellar nanoparticles of a dichalcogenide of a transition metal, which are lamellar nanoparticles of molybdenum disulfide.
However Liu discloses a similar two dimensional (i.e. lamellar) material supported filtration membrane, which may be used for desalination or selective ion filtration, wherein the active layer two dimensional material may be graphene or derivates thereof, and may comprise two-dimensional materials other than graphene, including molybdenum disulfide; wherein the graphene/two-dimensional material may be functionalized, wherein particles of graphene are deposited on a support including a non-woven nano porous fabric; Abstract, [0009], [0040], [0060]-[0061], [0069], [0064].
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to modify the composite of Garaj in view of Zhang and Schneiderman by substituting for the graphene oxide particles, or adding additionally to the graphene oxide layer, molybdenum disulfide particles in the as disclosed by Liu because this involves the simple substitution, or addition, of known two-dimensional/lamellar materials used in similar membranes to obtain the predictable result of forming a successful membrane.
Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over Garaj in view of Zhang and Schneiderman further in view of US 5,468,379 A1 (hereinafter “Yasuda”).
Regarding Claim 15 Garaj in view of Zhang and Schneiderman discloses the membrane according to claim 14, wherein Garaj discloses trialkylammonium groups; [0085], but does not disclose wherein the charged groups or the groups which become charged in the presence of water are the carboxyalkyl groups R-CO2- with B being C1 alkyl
However Yasuda discloses carboxyl and carboxyalkyl groups are known similar ion exchange groups (C1/L56-60, C5/L16-18).
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to modify the composite of Garaj in view of Zhang and Schneiderman by substituting for the carboxyl charged groups or the groups which become charged in the presence of water carboxyalkyl groups as disclosed by Yasuda because this involves the simple substitution of known similar ion exchange groups to obtain the predictable result of forming a successful ion exchange membrane.
i.e. where a carboxyalkyl functional group attached to the graphene would inherently have one carbon of the alkyl bonded to the graphene and another or the same carbon atom of the alkyl bonded to the carboxyl groups, i.e. that as claimed for a carboxyalkyl group groups R-CO2- with R being an alkyl. While it is not disclosed that R is specifically a C1 alkyl, it would have been obvious to try at least the most simple alkyl group i.e. methyl, for the alkyl group, which is thus a C1 alkyl.
Claim 17 is rejected under 35 U.S.C. 103 as being unpatentable over Garaj in view of Zhang and Schneiderman further in view of US 2020/0171434 A1 (hereinafter “Kamimura”).
Regarding Claim 17 Garaj in view of Zhang and Schneiderman discloses the membrane according to Claim 16, but does not disclose wherein the charged groups or the groups which become charged in the presence of water are the tertiary ammonium groups -N(H)R)2+ with R being a C1 alkyl.
However Kamimura discloses quaternary ammonium groups and tertiary ammonium groups are known similar ion exchange groups; [0091].
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to modify the composite of Garaj in view of Zhang and Schneiderman by substituting for the quaternary ammonium groups charged groups or the groups which become charged in the presence of water tertiary ammonium groups as disclosed by Kamimura because this involves the simple substitution of known similar ion exchange groups to obtain the predictable result of forming a successful ion exchange membrane.
i.e. where a tertiary ammonium group attached to the graphene would inherently have a Nitrogen with one bond to the graphene, one to a hydrogen, and two bonds to two alkyl groups, i.e. that as claimed for a tertiary ammonium group -N(H)R2⁺ with R being a alkyl. While it is not disclosed that R is specifically a C1-C4 alkyl, it would have been obvious to try at least the most simple alkyl group i.e. methyl, for the alkyl groups, which is thus a C1 alkyl.
Response to Amendment
The previous 35 U.S.C. 112(b) rejections of claims 4, 7 and 14-17 are withdrawn in view of Applicants’ arguments and amendments.
Response to Arguments
Applicants’ arguments filed 07/08/2026 have been fully considered, and they are persuasive with regard to the rejections citing Takamoto in view of Garaj and Schneiderman, but they are not persuasive with regard to the rejections citing Garaj in view of Zhang and Schneiderman.
The Examiner agrees that because Takamoto already discloses the nanofibers are coated in a hard, crossed linked resin, one of skill in the art would not be further motivated to crosslink the nanofibers; thus the rejections citing Takamoto in view of Garaj and Schneiderman are withdrawn.
In response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971).
In response to Applicants’ argument that one of skill in the art would not modify Garaj using the teachings of Zhang because Zhang is directed to an air filter not an ion exchange filter; the Examiner disagrees. Applicants’ argue that “[t]he person skilled in the art, starting from Garaj, which describes ion-selective membranes, would therefore not consult a document relating to an air filtration system.” However, Garaj is not solely to an ion-selective membrane, that is merely one of the uses described and the membrane is more broadly disclosed to be merely a nanofiltration membrane, or a filtration membrane. Thus one of skill in the art would look more broadly to all filtration membranes, where the disclosures in Zhang cited are directed to supporting a membrane broadly, and would therefore would obviously apply to the membrane of Garaj.
In response to Applicants’ argument that one of skill in the art would not modify Garaj using the teachings of Schneiderman because Schneiderman is directed to a cellulosic membrane; the Examiner disagrees. Applicants’ arguments ignore the combination of Garaj in view of Zhang, where the motivation to include two cellulosic filter paper support comes from Zhang. With regard to Garaj however, as noted by Applicants’ the support may be polymeric, and cellulose is a polymer, and thus there is no teaching away in Garaj from using a cellulosic membrane as support.
Conclusion
THIS ACTION IS MADE FINAL. 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.
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/ERIC J MCCULLOUGH/ Examiner, Art Unit 1773
/BENJAMIN L LEBRON/ Supervisory Patent Examiner, Art Unit 1773
