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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 07/21/2025 has been entered.
Status of Rejections
The rejection(s) of claim(s) 5 and 10 is/are obviated by applicant’s cancellation.
The rejection of claim(s) 43-47 under 35 USC 112(b) is/are withdrawn in view of applicant’s amendment.
All other previous rejections are maintained and modified only in response to the amendments to the claims.
Claims 1-4, 6-9, 11-21 and 43-47 are pending and under consideration for this Office Action.
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, 11-14, 16-21 and 43-47 are rejected under 35 U.S.C. 103 as being unpatentable over Yamaki et al. (U.S. 2019/0040537).
Regarding claim 1, Yamaki teaches a multilayer cation exchange membrane for use in a chloralkali process (see e.g. Paragraph 0010, lines 4-8, ion exchange membrane for alkali chloride electrolysis comprising layers C and S) comprising a fluorinated ionomer containing carboxylate groups on one side of the membrane (see e.g. Fig. 1, bottom layer (C) 12 made of fluorinated polymer having carboxylic acid functional groups; Paragraph 0046, lines 5-7), an exterior sulfonate layer comprising a fluorinated ionomer containing sulfonate groups on the side of the membrane opposite the carboxylate layer (see e.g. Fig. 1, top layer (Sb) 14B made of fluorinated polymer having sulfonic acid functional groups; Paragraph 0078, lines 5-7, and Paragraph 0079, lines 7-11), and an interior sulfonate layer comprising a fluorinated ionomer containing sulfonate groups between the carboxylate layer and the exterior sulfonate layer (see e.g. Fig. 1, middle layer (Sa) 14A made of fluorinated polymer having sulfonic acid functional groups; Paragraph 0078, lines 5-7, and Paragraph 0079, lines 3-7), the exterior sulfonate layer having an ion exchange ratio of 3.12 to 15.34, with a specific example of 13.12 (see e.g. Paragraphs 0090 and 0231, and Table 1, Example 6, layer Sb with preferable ion exchange capacities from 0.9 to 2.00 meq/g, which equates to an IXR of 3.12-15.34, and with Example 6 having a value of 1.0 meq/g, which equates to 13.12, based on the IEC converted to EW by 1000 divided by C, as described on Page 3 of the instant specification, and EW converted to IXR based on the formula 50IXR+344=EW for the first sulfonate type described on Page 11 of the instant specification and exemplified in Paragraph 0111 and Example 1 of Yamaki), and the interior sulfonate layer having an ion exchange ratio of 9.79 to 15.34, with a specific example of 11.3 (see e.g. Paragraph 0086, lines 1-3, and Paragraph 0231, and Table 1, Example 6, layer Sa with most preferable ion exchange capacities from 0.9 to 1.2 meq/g, which equates to an IXR of 9.79-15.34, and with Example 6 having a value of 1.1 meq/g, which equates to an IXR of 11.3, based on the IEC converted to EW by 1000 divided by C, as described on Page 3 of the instant specification, and EW converted to IXR based on the formula 50IXR+344=EW for the first sulfonate type described on Page 11 of the instant specification and exemplified in Paragraph 0111 and Example 1 of Yamaki), overlapping the claimed ranges of the present invention, the specific example for the exterior sulfonate layer falling within the claimed range and the specific example for the interior sulfonate layer being very close to, only 0.3 from, the claimed range.
MPEP § 2144.05 I states “In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists” and further states “Similarly, a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close.”.
Regarding claim 2, Yamaki teaches the interior sulfonate layer having an ion exchange ratio less than the ion exchange ratio of the exterior sulfonate layer by up to 5.55 (above calculated layer Sb IXR range of 3.12 to 15.34 greater than the above layer Sa IXR range of 9.79 to 15.34, by at most 5.55), overlapping the claimed range of the present invention (see MPEP § 2144.05 I as cited above), with a specific example of 1.82 (above calculated example of 13.12 for layer Sb and 11.3 for layer Sa).
Regarding claim 3, Yamaki teaches the carboxylate layer having an IXR of 12.0 to 14.9 or 14.3 to 17.2 (see e.g. Paragraph 0052 and Paragraph 0065 and 0071, layer C with most preferable ion exchange capacities from 0.95 to 1.10 meq/g, which equates to an IXR of 12-14.9 or 14.3-17.2, based on the IEC converted to EW by 1000 divided by C, as described on Page 3 of the instant specification, and EW converted to IXR based on the formulas 50IXR+308=EW or 50IXR+192=EW for the specific carboxylate polymers types described on Page 11 of the instant specification and Exemplified in Paragraphs 0065 and 0071 and Example 1 of Yamaki), overlapping the claimed range of the present invention (see MPEP § 2144.05 I as cited above), with particular examples of 14.68 and 15.3 (see e.g. Paragraph 0208 and Paragraph 0231, polymer C with monomer of formula Y having an IEC of 1.08 or 1.06 meq/g, equal to IXR of 14.68 and 15.3, respectively, based on the 2nd carboxylate equation conversion).
Regarding claims 4 and 6-8, Yamaki teaches the exterior sulfonate layer having an ion exchange ratio of 3.12 to 15.34, with a specific example of 13.12 (see e.g. Paragraphs 0090 and 0231, and Table 1, Example 6, layer Sb with preferable ion exchange capacities from 0.9 to 2.00 meq/g, which equates to an IXR of 3.12-15.34, and with Example 6 having a value of 1.0 meq/g, which equates to 13.12, based on the IEC converted to EW by 1000 divided by C, as described on Page 3 of the instant specification, and EW converted to IXR based on the formula 50IXR+344=EW for the first sulfonate type described on Page 11 of the instant specification and exemplified in Paragraph 0111 and Example 1 of Yamaki), overlapping or encompassing the claimed ranges of the present invention, the specific example falling within or being very close to the claimed ranges (see MPEP § 2144.05 I as cited above).
Regarding claims 9 and 11-12, Yamaki teaches the interior sulfonate layer having an ion exchange ratio of 9.79 to 15.34, with a specific example of 11.3 (see e.g. Paragraph 0086, lines 1-3, and Paragraph 0231, and Table 1, Example 6, layer Sa with most preferable ion exchange capacities from 0.9 to 1.2 meq/g, which equates to an IXR of 9.79-15.34, and with Example 6 having a value of 1.1 meq/g, which equates to an IXR of 11.3, based on the IEC converted to EW by 1000 divided by C, as described on Page 3 of the instant specification, and EW converted to IXR based on the formula 50IXR+344=EW for the first sulfonate type described on Page 11 of the instant specification and exemplified in Paragraph 0111 and Example 1 of Yamaki), overlapping or encompassing the claimed ranges of the present invention, the specific example again being very close to, only 0.3 or 0.4 from, the claimed ranges (see MPEP § 2144.05 I as cited above).
Regarding claim 13, Yamaki teaches the membrane further comprising a woven fabric reinforcement (see e.g. Fig. 1, reinforcing material 20 comprising fabric composed of warp and weft, i.e. woven, threads; Paragraph 0134).
Regarding claim 14, Yamaki teaches the woven fabric reinforcement being embedded in the membrane (see e.g. Fig. 1, reinforcing material 20 embedded in layer (S) 14; Paragraph 0045, lines 2-3).
Regarding claim 16, Yamaki teaches the interior sulfonate layer having a thickness of at least 40 micrometers (see e.g. Paragraph 0083, lines 1-4, layer Sa thickness preferably 40-140 µm, more preferably 40-90 µm).
Regarding claims 17-18, Yamaki teaches the interior sulfonate layer having a thickness of 40 to 90 micrometers (see e.g. Paragraph 0083, lines 1-4), overlapping the claimed ranges of the present invention (see MPEP § 2144.05 I as cited above).
Regarding claims 19-21, Yamaki teaches the exterior sulfonate layer having a thickness of 10 to 40 micrometers (see e.g. Paragraph 0088, lines 1-4), overlapping the claimed ranges of the present invention (see MPEP § 2144.05 I as cited above).
Regarding claim 43, Yamaki teaches a multilayer cation exchange membrane for use in a chloralkali process (see e.g. Paragraph 0010, lines 4-8, ion exchange membrane for alkali chloride electrolysis comprising layers C and S) comprising a fluorinated ionomer containing carboxylate groups on one side of the membrane (see e.g. Figs. 1-2, bottom layer (C) 12 made of fluorinated polymer having carboxylic acid functional groups; Paragraph 0046, lines 5-7), an exterior sulfonate layer comprising a fluorinated ionomer containing sulfonate groups on the side of the membrane opposite the carboxylate layer (see e.g. Figs. 1-2, top layer (Sb) 14B made of fluorinated polymer having sulfonic acid functional groups; Paragraph 0078, lines 5-7, and Paragraph 0079, lines 7-11), and first and second interior sulfonate layers comprising fluorinated ionomer containing sulfonate groups between the carboxylate layer and the exterior sulfonate layer (see e.g. Fig. 2, middle layers (Sa-1) 14Aa and (Sa-2) 14Ab making up layer 14A made of fluorinated polymer having sulfonic acid functional groups; Paragraph 0078, lines 5-7, and Paragraph 0126, lines 1-5), the first interior sulfonate layer being between the carboxylate layer and the second interior sulfonate layer (see e.g. Fig. 2, layer 14Aa between layers C and 14Ab) and the second interior sulfonate layer being between the first interior sulfonate layer and the exterior sulfonate layer (see e.g. Fig. 2, layer 14Ab between layers 14Aa and 14B), the exterior sulfonate layer having an ion exchange ratio of 3.12 to 12.17 (see e.g. Paragraph 0090, layer Sb with most preferable ion exchange capacities from 1.05 to 2.00 meq/g, which equates to an IXR of 3.12-12.17, based on the IEC converted to EW by 1000 divided by C, as described on Page 3 of the instant specification, and EW converted to IXR based on the formula 50IXR+344=EW for the first sulfonate type described on Page 11 of the instant specification and exemplified in Paragraph 0111 and Example 1 of Yamaki), the first interior sulfonate layer having an ion exchange ratio of 12.17 to 15.34 (see e.g. Paragraph 0127, lines 1-4, layer 14Aa with most preferable ion exchange capacities from 0.9 to 1.05 meq/g, which equates to an IXR of 12.17-15.34, calculated as above), and the second interior sulfonate layer having an ion exchange ratio of 7.93 to 14.63 (see e.g. Paragraph 0126, lines 6-11, and Paragraph 0127, lines 1-4, layer 14Ab with ion exchange capacity preferably 0.03 to 0.3 meq/g greater than the 0.9 to 1.05 meq/g of layer 14Aa, resulting in an IEC range of 0.93 to 1.35 meq/g, which equates to an IXR of 7.93-14.63, calculated as above), falling within or overlapping the claimed ranges of the present invention (see MPEP § 2144.05 I as cited above).
Regarding claim 44, Yamaki teaches the second interior sulfonate layer having an ion exchange ratio less than the ion exchange ratio of the exterior sulfonate layer by up to 4.24 (above calculated layer Sb/14B IXR range of 3.12 to 12.17 greater than the above layer 14Ab IXR range of 7.93 to 14.63, by at most 4.24), overlapping the claimed range of the present invention (see MPEP § 2144.05 I as cited above).
Regarding claim 45, Yamaki teaches the first interior sulfonate layer having an ion exchange ratio greater than the ion exchange ratio of the second interior sulfonate layer by 0.71 to 4.23 (see e.g. Paragraph 0126, lines 6-11, and Paragraph 0127, lines 1-4, layer 14Ab with ion exchange capacity preferably 0.03 to 0.3 meq/g greater than the 0.9 to 1.05 meq/g of layer 14Aa, resulting in an IEC range of 0.93 to 1.35 meq/g, which results in an IXR of 14Aa greater than that of 14Ab by 0.71 to 4.23), overlapping the claimed range of the present invention (see MPEP § 2144.05 I as cited above).
Regarding claim 46, Yamaki teaches the carboxylate layer having an IXR of 12.0 to 14.9 or 14.3 to 17.2 (see e.g. Paragraph 0052 and Paragraph 0065 and 0071, layer C with most preferably ion exchange capacities from 0.95 to 1.10 meq/g, which equates to an IXR of 12-14.9 or 14.3-17.2, based on the IEC converted to EW by 1000 divided by C, as described on Page 3 of the instant specification, and EW converted to IXR based on the formulas 50IXR+308=EW or 50IXR+192=EW for the specific carboxylate polymers types described on Page 11 of the instant specification), overlapping the claimed range of the present invention (see MPEP § 2144.05 I as cited above), with particular examples of 14.68 and 15.3 (see e.g. Paragraph 0208 and Paragraph 0231, polymer C with monomer of formula Y having an IEC of 1.08 or 1.06 meq/g, equal to IXR of 14.68 and 15.3, respectively, based on the 2nd carboxylate equation conversion).
Regarding claim 47, Yamaki teaches the first interior sulfonate layer having an ion exchange ratio that differs from the ion exchange ratio of the carboxylate layer by 0.66 to 3.13 (above calculated exemplary layer C IXR of 14.68 and 15.3 which differ from any point in the 12.17-15.34 IXR range of layer 14Aa by 0.66 to 3.13).
Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over Yamaki in view of Suzuki et al. (U.S. Patent No. 4,872,958).
Regarding claim 15, Yamaki teaches all the elements of the membrane of claim 13 as stated above. Yamaki does not explicitly teach the woven fabric comprising fluoropolymer yarns having a denier less than 100, only exemplifying fluoropolymer yarns of exactly 100 denier (see e.g. Paragraph 0136 and Paragraph 0213, lines 1-4, 100 denier PTFE threads) being used with a sacrificial PET yarns of 30 denier (see e.g. Paragraph 0213, lines 4-6).
Suzuki teaches an ion exchange membrane for electrolysis (see e.g. Abstract) comprising a woven or knitted fabric as a support including a reinforcing material comprising fluoropolymer yarns which preferably have a fineness of 50 to 200 denier (see e.g. Col. 6, lines 25-35 and 40-44), overlapping the denier value of Yamaki as well as the claimed range of the present invention (see MPEP § 2144.05 I as cited above), with a particular example of a woven fabric comprising 75 denier PTFE yarns and 30 denier PET yarns (see e.g. Col. 12, lines 64-67).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the fluoropolymer yarns of Yamaki to have a denier of preferably 50 to 200, particularly 75, as taught by Suzuki as a suitable fineness for reinforcing fluoropolymer yarns in a supporting woven fabric for an ion exchange membrane for electrolysis. MPEP § 2143(I)(A) states that “combining prior art elements according to known methods to yield predictable results” may be obvious. The claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination would yield nothing more than predictable results. Furthermore, MPEP § 2143(I)(B) states that “simple substitution of one known element for another to obtain predictable results” may be obvious. .
Response to Arguments
Applicant's arguments filed 07/21/2025 have been fully considered but they are not persuasive.
On pages 6-7, Applicant argues that Yamaki doesn’t teach the interior sulfonate layer having an IXR lower than that of the exterior sulfonate layers, or the specific ranges for claims 1 and 43, and that the prima facie case of obviousness for the overlapping ranges is overcome by the results of Comparative Example 9 shown in Table 2 of the instant specification that show the beneficial results of the outer sulfonate layer having a higher IXR than the inner sulfonate layer. This is not considered persuasive. Regarding claim 1, Yamaki, in addition to the overlapping ranges, provides an example in which the exterior sulfonate layer has an IXR of 13.12 which is greater than the 11.3 IXR of the interior sulfonate layer (see e.g. Table 1, Example 6, Sb with IEC of 1.0 meq/g and Sa with IEC of 1.1, which equate to 13.12 and 11.3, respectively, as calculated in the rejection above), the specific example for the exterior sulfonate layer falling within the claimed range and the specific example for the interior sulfonate layer being very close to, only 0.3 from, the claimed range. MPEP § 2144.05 I states “Similarly, a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close.”. Comparative Example 9 may show the benefit of a lower IXR for the interior sulfonate layer, but it does not serve as sufficient evidence for criticality of the specific IXR ranges of the sulfonate layers. To show that the claimed range is critical, Applicant must generally show that it achieves unexpected results relative to the prior art range. MPEP §716.02(d) states “To establish unexpected results over a claimed range, applicants should compare a sufficient number of tests both inside and outside the claimed range to show the criticality of the claimed range.”. Therefore, a prima facie case of obviousness still exists in consideration of the specific example of Yamaki which exhibits the supposed beneficial IXR relationship and falls within or is very close to the claimed ranges.
Regarding claim 43, no comparative examples are shown for the embodiment of three sulfonate layers to support criticality of their respective IXR ranges (see MPEP §716.02(d) as cited above). Therefore, the prima facie case of obviousness based on the overlapping ranges is maintained.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MOFOLUWASO S JEBUTU whose telephone number is (571)272-1919. The examiner can normally be reached M-F 9am-5pm.
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, Luan 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.
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.
/M.S.J./Examiner, Art Unit 1795
/LUAN V VAN/Supervisory Patent Examiner, Art Unit 1795