DETAILED ACTION
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 .
Election/Restriction, Response to Amendment, and Claim Status
Applicant’s election without traverse of Group I, Claims 1–11 in the reply filed on 28 August 2026 is acknowledged. Furthermore, the amendment filed 28 August 2026 has been entered. Claims 1–20 are pending in the application. Claims 12–20 are withdrawn from further consideration pursuant to CFR 1.142(b) as being drawn to a nonelected invention, there being no allowable generic or linking claim.
Specification
The disclosure is objected to because of the following informalities:
[0019] line 1: “pore sire distribution” should instead read “pore size distribution”;
[0073] line 6: “calibration curve .” should instead read “calibration curve.”;
[0079] line 5: “PEIAA particles (in DI water” should instead read “PEIAA particles in DI water”;
[0084] line 4: “at the100th cycle” should instead read “at the 100th cycle”;
[0088] line 4: “399 eV and 41.07 eV 31” should instead read “399 eV and 401.7 eV”.
Drawings
The drawings are objected to because: in FIG. 9, “cummulative” on the y-axis should be spelled “cumulative”.
Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance.
Appropriate correction is required.
Claim Objections
Claim 7 is objected to because of the following informality: “glycerol dimethacrylate” is listed twice. Appropriate correction is required.
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.
Claims 1–9 and 11 are rejected under 35 U.S.C. 103 as being unpatentable over Thomsen et al. (US 2017/0288243 A1) in view of Iijima et al. (US 2013/0316231 A1) as evidenced by Qiao et al. (“Nitrogen-Doped Carbon Felt as an Electrode Material for Vanadium Flow Batteries”), further in view of and as evidenced by Shimomura et al. (US 2009/0297890 A1), as further evidenced by Frech et al. (US 2002/0160271 A1).
Regarding Claim 1, Thomsen discloses an electrode (see electrode 50, [0057], FIG. 7), comprising:
a conductive substrate (see carbon felt, [0058]).
However, Thomsen does not disclose a crosslinked branched polymer disposed on at least a portion of a surface of the conductive substrate, the crosslinked branched polymer comprising a plurality of tertiary amine groups and a plurality of carboxylic acid groups, carbonyl groups, hydroxyl groups, or any combination thereof. Note that Thomsen does disclose that the electrode is utilized in a vanadium redox flow battery (see redox flow battery cell stack 100, [0057], FIG. 7, used in vanadium redox flow batteries, [0066]). Note also that Thomsen is analogous to the claimed invention as it is in the same field of redox flow batteries.
Iijima teaches a conductive substrate (see base material, [0077], [0095]); and a crosslinked polymer (see OH/NH2 polymer, [0037], disclosed in e.g. [0044] to be crosslinked; see specifically wherein the OH/NH2 polymer is polyethyleneimine, [0045]) disposed on at least a portion of a surface of the conductive substrate ([0077], [0095]), the crosslinked polymer comprising a plurality of amino groups (a person of ordinary skill in the art will understand that polyethyleneimine comprises a plurality of amino groups, as also evidenced by Shimomura [Chemical formula 3] (1); see also amino groups, [0037]) and a plurality of carbonyl groups (e.g. [0044] discloses that the crosslinked polymer is crosslinked by phosphonobutanetricarboxylic acid (PBTC), and e.g. [0097] discloses that the crosslinking occurs at temperatures as high at 250 °C; while not explicitly taught by Iijima, a person of ordinary skill in the art will understand that such a crosslinking reaction occurs between amino groups of polyethyleneimine and carboxylic acid groups of PBTC, with each crosslinking reaction resulting in the formation of an amide group, which contains a carbonyl group; note that one of ordinary skill in the art would also reasonably expect that after crosslinking is complete, a plurality of unreacted carboxylic acid groups from PBTC will remain in the final crosslinked polymer, and that each carboxylic acid group also contains a carbonyl group). Iijima teaches that disposition of the crosslinked polymer on the conductive substrate results in a material with excellent hydrophilicity in addition to other advantageous properties including conductivity, texture, durability, and waterproofness. Note that Iijima is analogous to the claimed invention as it is in the same field of functional polymer coatings for electrochemical applications.
Further, it is well known in the field of vanadium redox flow batteries that carbon felt, which is commonly used in electrodes, suffers from the problem of poor hydrophilicity, as evidenced by Qiao (Abstract).
It would therefore have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to modify the electrode of Thomsen such that it further comprises a crosslinked polymer disposed on at least a portion of a surface of the carbon felt conductive substrate, the crosslinked polymer comprising a plurality of amino groups and a plurality of carbonyl groups, as taught by Iijima, for the purpose of remedying the known problem evidenced by Qiao of poor hydrophilicity of carbon felt in electrodes of vanadium redox flow batteries, and further providing other advantageous properties including conductivity, texture, durability, and waterproofness.
Modified Thomsen as set forth above does not specifically disclose wherein the crosslinked polymer is branched, nor wherein the plurality of amino groups are tertiary.
Shimomura teaches an electrode (see anode, [0019]), comprising: a conductive substrate (see electroconductive base material, [0024]; see specifically wherein the electroconductive base material is carbon felt, [0025]); and a crosslinked polymer (see hydrophilic polymer, [0028], which can be crosslinked, [0035], and branched, [Chemical formula 3] (1) and [0045]) disposed on at least a portion of a surface of the conductive substrate ([0023]), the crosslinked branched polymer comprising a plurality of tertiary amino groups ([Chemical formula 3] (1) shows that branched polyethyleneimine comprises a plurality of tertiary amino groups; one of ordinary skill in the art will understand that even after crosslinking, the plurality of tertiary amino groups will still be present, as evidenced by Frech general formula (3) and [0033]) and a plurality of carbonyl groups ([0019] discloses that an electron mediator is chemically bound to the hydrophilic polymer layer; [0053] discloses that the electron mediator can be e.g. anthraquinone-2-carboxylic acid (AQC), and that the hydrophilic polymer in the form of polyethyleneimine reacts with the carboxyl group of AQC to form an amide group; one of ordinary skill in the art will understand that a plurality of carbonyl groups will therefore be present in the crosslinked branched polymer, both in these formed amide groups, and in the ketone groups present in the central ring of the AQC). Shimomura teaches ([0045]) that when the crosslinked polymer is branched, it has increased adhesiveness compared to polymers of the same molecular weight, which is preferable. Note that Shimomura is analogous to the claimed invention as it is in the same field of functional polymer coatings for electrochemical applications.
It would therefore have been obvious to a person of ordinary skill in the art to modify the electrode of modified Thomsen such that the crosslinked polymer is branched, as taught by Shimomura, for the purpose of increasing adhesiveness. One of ordinary skill in the art will understand that such a modification will necessarily result in the crosslinked branched polymer comprising a plurality of tertiary amino groups (as already set forth above, [Chemical formula 3] (1) of Shimomura evidences that branched polyethyleneimine comprises a plurality of tertiary amino groups; one of ordinary skill in the art will understand that even after crosslinking, the plurality of tertiary amino groups will still be present, as evidenced by Frech general formula (3) and [0033]).
Regarding Claim 2, modified Thomsen discloses the electrode as set forth above. As already set forth above, Thomsen discloses wherein the conductive substrate comprises carbon felt ([0058]).
Regarding Claim 3, modified Thomsen discloses the electrode as set forth above, but does not explicitly disclose wherein the crosslinked branched polymer coats individual carbon fibers on a surface of the conductive substrate.
However, modified Thomsen does disclose wherein the crosslinked branched polymer coats the surface of the conductive substrate (Iijima [0095]). Furthermore, it is well-known in the field of redox flow batteries that carbon felt is formed of carbon fibers, as evidenced by Qiao (¶ “As shown in Figure…” and Figure 3), and thus it can be understood that carbon fibers will be present on the surface of carbon felt.
It will therefore necessarily be the case for the electrode of modified Thomsen that the crosslinked branched polymer coats, at least to some extent, individual carbon fibers on the surface of the carbon felt conductive substrate.
Regarding Claim 4, modified Thomsen discloses the electrode as set forth above. As already set forth above, modified Thomsen discloses wherein the crosslinked branched polymer comprises a branched polyalkylene imine polymer in the form of branched polyethyleneimine. In addition to being crosslinked with PBTC (which comprises three oxygen-containing reactive groups that are -COOH groups) as already set forth above, modified Thomsen further discloses wherein the branched polyalkylene imine polymer is crosslinked with a crosslinker (see crosslinking agent, Iijima [0081]) comprising at least two oxygen-containing reactive groups, where the at least two oxygen-containing reactive groups are C(O) groups (see e.g. glutaraldehyde, glyoxal, and polyethylene glycol dimethacrylate, Iijima [0086]), epoxy groups (see e.g. ethylene glycol diglycidyl ether and polyethyleneglycol diglycidyl ether, Iijima [0086]), or -COOH groups (see e.g. oxalic acid, tartaric acid, citric acid, malic acid, succinic acid, Iijima [0082]).
Regarding Claim 5, modified Thomsen discloses the electrode as set forth above. As already set forth above, modified Thomsen discloses wherein the branched polyalkylene imine polymer comprises branched polyethyleneimine.
Regarding Claim 6, modified Thomsen discloses the electrode as set forth above. Modified Thomsen further discloses wherein the branched polyalkylene imine polymer has a weight average molecular weight Mw of 5 kDa to 2000 kDa (Iijima [0055]), which encompasses the instantly claimed range of 20 kDa to 30 kDa. Iijima teaches ([0055]) that when the weight average molecular weight lies within the range of 5 and 2000 kDa, issues of brittleness of the polyalkylene imine polymer and nonuniformity of the coating composition can be avoided.
It would have been obvious to a person of ordinary skill in the art to utilize a branched polyalkelyeneimine polymer having a weight average molecular weight Mw in the encompassing portion of the weight average molecular weight Mw range disclosed by modified Thomsen, wherein the skilled artisan would have a reasonable expectation of successfully forming the crosslinked branched polymer desired by modified Thomsen while avoiding issues of brittleness of the polyalkylene imine polymer and nonuniformity of the coating composition.
The examiner notes that the limitation by light scattering is a product-by-process limitation and therefore is not given patentable weight aside from the implied structure of the product.
In a product-by-process limitation, so long as the product has the same claimed composition or properties, the method by which it was made or by which the properties were tested is not material. According to the MPEP, “even though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process. See In re Thorpe, 777 F.2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985) (see MPEP § 2113).
Regarding Claim 7, modified Thomsen discloses the electrode as set forth above. As already set forth above, modified Thomsen discloses wherein the crosslinker comprises glutaraldehyde (Iijima [0086]), glyoxal (Iijima [0086]), oxalic acid (Iijima [0082]), tartaric acid (Iijima [0082]), citric acid (Iijima [0082]), malic acid (Iijima [0082]), succinic acid (Iijima [0082]), ethylene glycol diglycidyl ether (Iijima [0086]), poly(ethylene glycol) diglycidyl ether (Iijima [0086]), or poly(ethylene glycol) dimethacrylate (Ijima [0086]).
Regarding Claim 8, modified Thomsen discloses the electrode as set forth above. As already set forth above, modified Thomsen discloses wherein the crosslinked polymer comprises branched polyethyleneimine, and wherein the branched polyethyleneimine is crosslinked with glutaraldehyde (Iijima [0086]).
Regarding Claim 9, modified Thomsen discloses the electrode as set forth above. Modified Thomsen further discloses wherein the crosslinked branched polymer comprises the branched polyalkylene imine polymer and the glutaraldehyde in a weight ratio of 0.5:1 to 10000:1 (see the content of one or more of these crosslinking agents may be set preferably at 0.01 to 200 mass% based on the OH/NH2 polymer, Iijima [0086]), which encompasses the instantly claimed range of 3:1 to 7:1.
It would have been obvious to a person of ordinary skill in the art to form the crosslinked branched polymer of modified Thomsen to comprise the branched polyalkylene imine polymer and the glutaraldehyde in the encompassing portion of the weight ratio disclosed by modified Thomsen, wherein the skilled artisan would have a reasonable expectation of successfully forming the crosslinked branched polymer desired by modified Thomsen.
Regarding Claim 11, modified Thomsen discloses the electrode as set forth above. As already set forth above, modified Thomsen discloses wherein:
the conductive substrate comprises carbon felt (Thomsen [0058]); and
the crosslinked branched polymer comprises branched polyethyleneimine.
In addition to being crosslinked with PBTC as already set forth above, modified Thomsen further discloses wherein the branched polyethyleneimine is crosslinked with glutaraldehyde (see crosslinking agent, Iijima [0081]; see specifically wherein the crosslinking agent is glutaraldehyde, Iijima [0086]).
Allowable Subject Matter
Claim 10 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter:
The closest prior art is considered to be Thomsen et al. in view of Iijima et al. as evidenced by Qiao et al., further in view of and as evidenced by Shimomura et al., as further evidenced by Frech et al., as applied in the rejection above.
However, regarding Claim 10, modified Thomsen as set forth above does not disclose, teach, or suggest the following distinguishing feature: the crosslinked branched polymer is disposed on 10% to 30% of a surface area of the conductive substrate.
In the experimental example of the instant application, disposition of the crosslinked polymer onto the conductive substrate on only a percentage of the surface area appears to have been achieved by dipping only one fifth of the conductive substrate into the prepared solutions ([0070]).
However, none of the cited references nor any references found by the examiner appear to contemplate treatment of only a portion of the conductive substrate with prepared solutions such that only a percentage of the surface area would be covered by the crosslinked branched polymer (the examiner notes that the surface area as claimed is considered to be the total area of all surfaces of the conductive substrate). For instance, Iijima discloses ([0095]) applying the polymer to the surface of the conductive substrate in a general sense to a desired thickness, but not across a desired percentage of the surface area of the conductive substrate.
Furthermore, the instant application discloses that surface area, average pore size, and pore volume decrease after modification with the crosslinked branched polymer ([0078], Table 1, FIG. 9), which leads to a decrease in energy efficiency ([0083]). A person of ordinary skill in the art can understand that such effects would be more or less pronounced depending on the percentage of surface area of the conductive substrate covered by the crosslinked polymer.
In contrast, none of the cited references nor any references found by the examiner disclose such effects which would reasonably be expected to arise from the extent to which the surface area of the conductive substrate is coated with the crosslinked branched polymer. As such, it would not have been obvious to modify the electrode of modified Thomsen via routine experimentation in order to achieve disposition of the crosslinked branched polymer on a specific percentage of the surface area of the conductive substrate, such as 10% to 30% as claimed, in order to achieve certain effects or properties of the electrode.
In conclusion, there is no teaching or motivation found in the above prior art references nor any other references found by the examiner that teach the cumulative limitations of Claim 10.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JULIA MARIE FEHR, Ph.D. whose telephone number is (571)270-0860. The examiner can normally be reached Monday - Friday 9:00 AM - 5:00 PM EST.
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/J.M.F./Examiner, Art Unit 1725
/KIMBERLY WYLUDA/Primary Examiner, Art Unit 1725
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