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 .
Status of the Claims
This is a final Office action in response to Applicant’s amendments and remarks filed 08/28/2026. Claims 1-20 are pending in the current Office action. Claims 1-3, 5-6, and 10-12 were amended by Applicant. Claims 13-20 are new claims.
Status of the Rejection
The rejections of claims 5 and 10-12 under 35 U.S.C. § 112(b) are withdrawn in view of Applicant’s amendments.
The rejections of claims 1-12 under 35 U.S.C. § 103 are withdrawn in view of Applicant’s amendments.
New rejections are necessitated by Applicant’s amendments.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1-4, 6-9, and 13-20 are rejected under 35 U.S.C. 103 as being unpatentable over Inoue (US Pat. Pub. 2017/0333846 A1) as evidenced by, in the case of claims 4 and 7-9, Korngold (US Pat. No. 3686089).
Regarding claim 1, Inoue teaches a polymer ion exchange membrane (“composite anion exchange membrane” abstract and para. 14), comprising:
an ion exchange resin (A) (“an anion exchange membrane substrate,” abstract and para. 15); and
an ion exchange resin (B) (“a surface layer on a single surface or both surfaces of an anion exchange membrane substrate” abstract and para. 15),
wherein a (DA - DB) difference between a basic site density DA of the ion exchange resin (A) and a basic site density DB of the ion exchange resin (B) is 0.5-4.95 mmol/cm3 (“an anion exchange capacity of the above-described surface layer is 0.05 meq/cm3 to 0.50 meq/cm3, and an anion exchange capacity of the above described anion exchange membrane substrate is 1.0 meq/cm3 to 5.0 meq/cm3” abstract and para. 15)1, a range within the claimed range,
wherein the polymer ion exchange membrane has a laminated structure in which a layer comprising the ion exchange resin (A) and a layer comprising the ion exchange resin (B) are laminated (“an anion exchange membrane substrate 1 has surface layers 2 on both surfaces… but may have a surface layer 2 on a single surface.” para. 46 and Fig. 1), and
wherein a thickness ratio of a total thickness of the layer comprising the ion exchange resin (A) (“The thickness of the above-described acrylic anion exchange membrane as a composite containing a porous support and a resin layer is preferably 10 to 250 μm” para. 160) to a total thickness of the layer comprising the ion exchange resin (B) (“The thickness of the surface layer used in the present invention, as the thickness of a single surface, is preferably 1 to 50 μm,” para. 54) is in a range of from 250:1 to 5:1, a range touching the claimed range2. A range in the prior art touching a claimed range establishes a prima facie case of obviousness (MPEP § 2144.05(I)).
Regarding claim 2, Inoue further teaches the basic site density DA is in a range from 1.0 meq/cm3 to 5.0 meq/cm3 (“an anion exchange capacity of the above described anion exchange membrane substrate is 1.0 meq/cm3 to 5.0 meq/cm3” para. 15), a range overlapping the claimed range. A range in the prior art overlapping a claimed range establishes a prima facie case of obviousness (MPEP § 2144.05(I)).
Regarding claims 3 and 6, Inoue renders the limitations of claims 1 and 2 obvious, as described above.
Inoue further teaches the basic site density DB is in a range from 0.05 meq/cm3 to 0.50 meq/cm3 (“an anion exchange capacity of the above-described surface layer is 0.05 meq/cm3 to 0.50 meq/cm3” para. 15), a range overlapping the claimed range. A range in the prior art overlapping a claimed range establishes a prima facie case of obviousness (MPEP § 2144.05(I)).
Regarding claims 4 and 7-9, Inoue renders the limitations of claims 1-3 and 6 obvious, as described above.
Inoue further teaches a solid-electrolyte electrolytic device comprising the polymer ion exchange membrane of claim 1 (“an ion exchange device in which the composite anion exchange membrane of the present invention is used.” para. 31 and Fig. 2, see also para. 251).3
Regarding claim 13, Inoue renders the limitations of claim 1 obvious, as described above.
Inoue does not teach the thickness ratio is in a range of from 1:3 to 3:1. Inoue instead teaches the thickness ratio is in a range of 10:1 to 5:1, a range close to the claimed range. A range in the prior art close to a claimed range i.e., such that a person having ordinary skill in the art would not have expected a material difference between the prior art and the claimed range, establishes a prima facie case of obviousness (MPEP § 2144.05(I)).
Currently, there is no evidence of record that the specific thickness range recited i.e., 3:1 to 1:3, results in materially different properties relative to the range taught by Inoue. It is therefore considered that a person having ordinary skill in the art would not have expected the difference in thickness ratios to have a material effect on the overall properties of the membrane. Therefore, the cumulative limitations of claim 13 are prima facie obvious over the teachings of Inoue.
Regarding claims 14-19, Inoue renders the limitations of claim 1 obvious, as described above.
Inoue further teaches a total mass of the ion exchange resin (A) and the ion exchange resin (B) in the polymer ion exchange membrane is up to 100% by mass, a range encompassing within the claimed ranges and value (see below). A range in the prior art encompassing a claimed range or value establishes a prima facie case of obviousness (MPEP § 2144.05(I)).
Regarding the total mass of the ion exchange resins taught by Inoue, Inoue recites a number of additional optional components that may be added to the ion exchange membrane, but only requires the membrane comprise the ion exchange resins (A) and (B). In the case where only the ion exchange resins (A) and (B) are present, they necessarily comprise 100% of the mass of the ion exchange membrane. Thus, Inoue teaches a total mass of the ion exchange resin (A) and the ion exchange resin (B) in the polymer ion exchange membrane is up to 100% by mass.
Regarding claim 20, Inoue renders the limitations of claim 1 obvious, as described above.
Inoue further teaches the ion exchange resin (A) (“The fluorine-based anion exchange membrane in the present invention represents an anion exchange membrane containing a perfluoroalkylene group-containing resin.” para. 154) and/or ion exchange resin (B) is a fluororesin-based ionomer anion exchange membrane (“Examples of halogen ions in XA1 include fluoride ions, chlorine ions, bromine ions, and iodide ions.” para. 80, see also paras. 55 and 73 et seq.).
Allowable Subject Matter
Claims 5 and 10-12 are 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:
Regarding claim 5, the prior art of record, alone or in combination, does not reasonably teach or render obvious the cumulative limitations of claim 5, with a particular emphasis on the limitations “wherein a wherein a (DA - DB) difference between a basic site density DA of the ion exchange resin (A) and a basic site density DB of the ion exchange resin (B) is 0.3 mmol/cm3 or more,”, “wherein a thickness ratio … is in a range of from 1:5 to 5:1” (claim 1) and “applying a voltage … to reduce the carbon dioxide” (claim 5).
The closest prior art is considered to be Kuhl (US Pat. Pub. 2021/0395908 A1) and Inoue (US Pat. Pub. 2017/0333846 A1).
Inoue renders the limitations of claim 4 obvious, as described above.
Inoue further teaches applying a voltage to the solid-electrolyte electrolytic device (para. 290), and can reasonably be considered to inherently or implicitly teach a step of contacting carbon dioxide with the solid-electrolyte electrolytic device (no particular steps to remove carbon dioxide from the aqueous solution electrolyzed are described, and there would generally be no need for such steps in an electrodialysis process).
However, Inoue does not teach the applied voltage results in the reduction of carbon dioxide, but rather the reduction of water to hydrogen gas. Neither can the method of Inoue reasonably be considered to inherently reduce carbon dioxide. Furthermore, as the method of Inoue is directed to electrodialysis, a person having ordinary skill in the art would not have had a motivation to modify the method of Inoue such that it results in the reduction of carbon dioxide.
Therefore, Inoue does not reasonably teach or disclose the cumulative limitations of claim 5.
The teachings of Kuhl are detailed in the Office action mailed 05/29/2026. In brief, Kuhl a method of carbon dioxide reduction using a solid-electrolyte electrolytic device comprising a polymer ion exchange membrane comprising:
two ion exchange resins (A) and (B) having a laminated structure (Fig. 5), wherein a difference between a basic site density of the ion exchange resins (DA-DB) is up to 1.8 mmol/cm3 (para. 332)4, a range overlapping the claimed range.
However, Kuhl does not teach a thickness ratio of a total thickness of the layer comprising the ion exchange resin (A) to a total thickness of the layer comprising the ion exchange resin (B) is in a range from 1:5 to 5:1. Rather, as noted by Applicant (see Remarks p. 6, filed 08/28/2026), Kuhl teaches the thickness ratio is between 1:1000 and 1:10 (para. 332). I.e., Kuhl teaches the layer (B) should be thinner than the minimum claimed thickness ratio. Absent a motivation in the prior art to modify the system of Kuhl to use a thicker anion exchange layer, Kuhl is not considered to render the limitation “wherein a thickness ratio … is in a range of from 1:5 to 5:1” obvious.
No particular motivation to modify the method of Inoue or the system of Kuhl to read on the cumulative limitations of claim 5 could be identified in the prior art.
It is therefore considered that the cumulative limitations of claim 5 are patentably distinguished over the prior art of record. Therefore, claim 5 would be allowable if rewritten in independent form including the each of the limitations of the base and intervening claims.
Regarding claims 10-12, claims 10-12 incorporate each of the limitations of claim 5, and therefore recite the same patentably distinguished subject as claim 5. Claims 10-12 are therefore patentably distinguished over the prior art for at least the same reasons enumerated for claim 5, above. Therefore, claims 10-12 would be allowable if rewritten in independent form including the each of the limitations of the base and intervening claims.
Response to Arguments
Applicant’s arguments, see Remark p. 5-8, filed 08/28/2026, with respect to the rejection(s) of claim(s) 1-12 under 35 U.S.C. § 103 have been fully considered and are persuasive in part. Therefore, the rejections have been withdrawn. However, new grounds of rejection are established as necessitated by Applicant’s amendments.
Applicant’s Argument #1
Applicant argues on p. 7-8 that the instant invention provides unexpectedly superior results, which should overcome any prima facie case of obviousness. Specifically, Applicant argues that the data in Tables 1 and 2 demonstrate the membranes as claimed provide unexpectedly improved suppression of H2 production during carbon dioxide reduction.
Examiner’s Response #1
Examiner respectfully disagrees. At issue is whether the data provided in Tables 1 and 2 of the instant application constitutes unexpected results sufficient to overcome a prima facie case of obviousness.
In order for unexpected results to overcome a prima facie case of obviousness, Applicant must provide evidence that has a nexus to the claimed invention (MPEP § 716.01(b)), such evidence must be commensurate in scope with the claims (MPEP § 716.02(d)), the evidence must demonstrate a benefit over the closest prior art (MPEP § 716.02(e)), and Applicant must demonstrate that any such benefit demonstrated is, in fact, unexpected (MPEP § 716.02(b)(I) and 716.02(c)).
In the instant case, Applicant has indicated that the data provided in tables 1 and 2 demonstrate that a basic site density difference of 0.3 mmol/cm3 or higher results in reduced hydrogen production during carbon dioxide electrolysis.
Claim 1, as currently drafted, recites a basic side density difference of 0.3 mmol/cm3 or more. Therefore, Applicant’s evidence has a nexus to the claimed invention.
However, the evidence provided by Applicant cannot reasonably be considered commensurate in scope with the claimed invention. Specifically, claim 1 is drawn to a membrane composition, but Applicant’s asserted benefit occurs only when the membranes are used for electrochemical carbon dioxide reduction.
Furthermore, Applicant’s evidence is not considered sufficient to demonstrate that the asserted benefit of inhibiting hydrogen production in fact requires a basic site density difference (DA-DB) of 0.3 mmol/cm3 or greater. Specifically, Applicant has provided two (2) data points having a layer (A) and (B) in Table 1, the first data point corresponds to (DA-DB) = 0.2 mmol/cm3 (“comparative example 4”) and the second data point corresponds to (DA-DB) = 1.5 mmol/cm3 (“example”). Two data points are not sufficient to support unexpected results over the range of “(DA-DB) … is 0.3 mmol/cm3 or greater” as currently claimed. It is further noted that the data provided in Table 2 are for membranes comprising three layers, a feature not currently recited in the claims, and therefore cannot be directly compared with the data in Table 1.
As the evidence provided by Applicant is not commensurate in scope with the claims as currently drafted, Applicant’s evidence is not considered to overcome the prima facie case(s) of obviousness established in the current Office action.
Applicant’s argument is thus unpersuasive.
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 ALEXANDER R PARENT whose telephone number is (571)270-0948. The examiner can normally be reached M-F 11:00 AM - 6 PM EST.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Luan V. Van can be reached at (571)272-8521. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/ALEXANDER R. PARENT/Examiner, Art Unit 1795
/LUAN V VAN/Supervisory Patent Examiner, Art Unit 1795
1 The minimum difference calculated as 1.0 meq/cm3 - 0.50 meq/cm3, and the maximum difference calculated as 5.0 meq/cm3 - 0.05 meq/cm3.
2 It is considered that Inoue implicitly teaches the layer B is thinner than the layer A. Therefore, the thickness range was calculated by dividing the maximum thickness for layer A by the minimum thickness for layer B i.e., 250/1, and dividing the maximum thickness for layer A by the maximum thickness for layer B i.e., 250/50. Absent this implicit teaching, Inoue teaches the thickness range is 1:250 to 5:1, a range encompassing the claimed range.
3 As evidenced by e.g., Korngold, electrodialysis is driven by water electrolysis at the anode and cathode (col. 8 lines 10-14).
4 As noted by Applicant (see Remarks p. 5, filed 08/28/2026), this range was originally indicated as 0 to 1.5 mmol/cm3 due to a math error.
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