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/Restrictions
Applicant’s election without traverse of Group I (Claims 1-12) in the reply filed on 09/09/2026 is acknowledged.
Claims 13 & 14 are withdrawn as being directed to a non-elected invention.
Claim Rejections - 35 USC § 102
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 the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1, 2, 4, 5, 7, and 10 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Taskier ‘510 (US 4,359,510).
Claim 1: Taskier ’510 discloses a method of manufacturing a separator for a secondary battery, the coated microporous membrane being employed as a separator in primary or secondary battery cells, including a rechargeable zinc-anode secondary battery (claims 11–13). The method comprises dissolving an ion conductive resin and a surfactant in an organic solvent to produce a mixed solution: Taskier mixes a coating polymer (cellulose acetate) together with a surfactant in an organic solvent such as acetone (col. 22, lines 36-38; Table 1, reciting cellulose acetate / surfactant / acetone in a 5 / 5 / 90 weight ratio, col. 27). Under the broadest reasonable interpretation, the cellulose-ester coating polymer is an “ion conductive resin,” because Taskier teaches that the coating functions by “transporting electrolyte through the coating by diffusion” (col. 21, lines 8-11) and that the separator’s electrical resistance — defined as “the ability of the microporous membrane to conduct ions” (col. 19, lines 8-10) — is reduced by the coating; that is, the resin conducts ions of the electrolyte through the separator.
The method further comprises impregnating at least one surface of a porous membrane with the mixed solution. Taskier applies the polymer-plus-surfactant solution to at least one surface of a normally hydrophobic microporous (porous) polyolefin membrane (claim 1), whereupon the surfactant is carried into and deposited within the pores of the substrate membrane (col. 23, lines 11-14), i.e., the porous membrane is impregnated with the mixed solution.
Claim 2: Taskier discloses the method of claim 1 and further discloses that the substrate membrane, prior to impregnation, is normally hydrophobic, and that impregnating it with the surfactant-containing mixed solution renders the substrate microporous membrane hydrophilic (claim 1; col. 8, lines 15-19). The porous membrane thus exhibits hydrophobicity when not impregnated and becomes hydrophilic upon impregnation of at least one surface.
Claim 4 & 5: Taskier teaches “silicon glycol copolymers, such as polyoxyethylene polymethyl siloxane” which is a silicone-based organic surfactant (Col. 22, lines 1-4).
Claim 7: Taskier discloses the method of claim 1, wherein the porous membrane is made of polypropylene, polyethylene, or a combination thereof — the microporous film being formed from olefin polymers including polyethylene and polypropylene (col. 12, lines 5-10; claims 7 and 10).
Claim 10: Taskier discloses the method of claim 1, wherein the method further comprises, after impregnating the at least one surface of the porous membrane, drying the porous membrane — “Upon drying of the coating” (col. 22, lines 32-35) — Example 1 drying the coated film in an oven at 175° F. (Part E).
Claim Rejections - 35 USC § 103
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 3, 8, 9 are rejected under 35 U.S.C. 103 as being unpatentable over Taskier ‘510.
Claim 3: Taskier teaches the method of claim 1 as set forth above and discloses that the surfactant admixed with the coating polymer constitutes from about 20% to about 200% by weight of the coating polymer (col. 24, lines 1-4), exemplifying a mixed solution of cellulose acetate / surfactant / acetone in a 5 / 5 / 90 weight ratio (Table 1) — i.e., a surfactant content of about 5 wt% of the mixed solution, with the lower preferred ratios (about 50–70% of the ≈5 wt% polymer) yielding surfactant contents of roughly 2.5–3.5 wt% of the mixed solution. Taskier therefore discloses surfactant contents overlapping the claimed range of 0.1% (exclusive) to 5.0% (exclusive) by weight of the mixed solution. Where the prior art discloses a range that overlaps or abuts the claimed range, a prima facie case of obviousness exists (MPEP 2144.05). It would have been obvious before the effective filing date to select a surfactant content within the claimed range, the surfactant content being a reasonable variable governing the hydrophilicity and electrical resistance of the separator.
Claim 8: Taskier teaches the method of claim 1 and discloses dissolving the coating polymer and surfactant in a two-solvent system comprising a major organic solvent together with a minor co-solvent used to control the viscosity of the solution — e.g., a 9-parts-acetone / 1-part-ethanol solvent in which the cellulose-acetate solution viscosity is characterized (col. 21, lines 24-28), and methylene chloride / methanol (9:1) and ketone solvents (col. 22, lines 36-40). It would have been obvious to dissolve the ion conductive resin and surfactant in such a viscosity control solvent and the organic solvent, and to select the viscosity control solvent content (the disclosed minor co-solvent fraction, encompassing the claimed 10% to 25% by weight).
Claim 9: Taskier teaches the method of claim 8 as set forth above and expressly discloses the recited viscosity control solvents — acetone, methylethylketone, methanol, and ethanol (col. 21–22) — rendering obvious the selection of at least one of acetone, methyl ethyl ketone, methyl isobutyl ketone, methanol, ethanol, isopropanol, butanol, or isobutanol as the viscosity control solvent.
Claims 6, 11, and 12 are rejected under 35 U.S.C. 103 as being unpatentable over Taskier ‘510 in view of Benicewicz ‘539 (US 2020/0091539 A1).
Claim 6: Taskier teaches the method of claim 1 — dissolving an ion conductive resin and a surfactant in an organic solvent and impregnating at least one surface of a porous polyolefin membrane with the mixed solution — but employs a cellulose-ester coating resin and does not disclose a polybenzimidazole-based ion conductive resin. Benicewicz ’539 discloses polybenzimidazole (PBI) as the ion-conductive separator resin for a redox flow battery, conventionally prepared by “solution casting in N,N-dimethylacetamide (DMAc) to form a dense film” used as a separator ([0006] & [0125]), and teaches that PBI separators exhibit low vanadium permeability, high ionic conductivity, and resistance to degradation in the oxidative vanadium environment (Abstract; [0031]). It would have been obvious before the effective filing date to substitute PBI for the cellulose-ester resin dissolved and impregnated by the method of Taskier motivated by the benefits Benicewicz attributes to PBI, PBI being solution-castable from an organic solvent (DMAc) in the same manner as the coating resins.
Claim 11: Taskier teaches the method of claim 1 but does not disclose the secondary battery employing an aqueous electrolyte as a liquid electrode. Benicewicz ’539 discloses a vanadium redox flow battery in which the positive and negative electrolyte solutions serve as the liquid electrodes ([0075–0076]), the electrolyte being an aqueous solution ([0089]). One of ordinary skill combining the separator-fabrication method of Taskier ’510 with the redox-flow-battery teaching of Benicewicz ’539, for the reasons given for claim 6, would arrive at a separator for a secondary battery that employs an aqueous electrolyte as a liquid electrode, as taught by Benicewicz ’539.
Claim 12: Benicewicz ’539 discloses that the aqueous electrolyte of the redox flow battery contains vanadium ions and an acidic aqueous solution — a sulfuric acid aqueous electrolyte in which vanadium alternates between its several oxidation states (Abstract; [0089]; [0099], reciting 2.6M H2SO4). It would have been obvious, for the reasons set forth for claims 6 and 11, to make the separator of the Taskier ’510 / Benicewicz ’539 combination for a battery whose aqueous electrolyte contains vanadium ions and an acidic aqueous solution, as taught by Benicewicz ’539.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ATEF A SHAT whose telephone number is (571)270-0364. The examiner can normally be reached 8am-5pm.
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/ATEF A SHAT/Examiner, Art Unit 1712
/MICHAEL B CLEVELAND/Supervisory Patent Examiner, Art Unit 1712
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