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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 26 March 2026 has been entered.
Response to Amendment
Acknowledgment is made to Applicant’s claim amendments received 27 February 2026. Claims 1-9 are currently pending of which claim 1 is currently amended, claim 5 is withdrawn from consideration and claim 9 is new.
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, 2, 4, 7 and 8 are rejected under 35 U.S.C. 103 as being unpatentable over US Patent Application Publication No. 2013/00324761 to Yao et al. (Yao) in view of US Patent Application Publication No. 2013/0008783 A1 to Shodai et al. (Shodai).
As to claims 1 and 2, Yao teaches a method for producing fluorine gas, the fluorine gas produced by electrolyzing an electrolyte (molten salt) containing hydrogen fluoride and a metal fluoride, potassium fluoride, the method comprising, electrolyzing the electrolyte in an electrolytic cell (1) and measuring a water concentration in an electrolytic cell (Paragraphs 0018, 0053 and 0054; Figure 1). Yao teaches that when the water concentration is measured higher than a reference value a fluid generated inside the electrolytic cell is sent from the inside of the cell to an outside of the cell through a flow path, corresponding to the second flow path of the claims, (branch passage (72)) and when the water concentration is measured lower than a reference value the cell start up is finished and normal operation proceeds wherein the fluid generated within the electrolytic cell inside is sent outside the cell via a another flow path, corresponding to the first flow path of the claims (main passage (15)), Yao thus teaching this operation occurs from a start of electrolysis (cell start up) at least until stable electrolysis starts (normal operation). Yao further teaches that the first flow path comprising a refining device (16) for removing liquid hydrogen fluoride entrained within the fluoride gas, thus acting as a both a mist removal unit and clogging suppression mechanism, the refining device comprising a section (50) for retaining the hydrogen fluoride, thus a mist pool space, formed on the flow path after a first portion of the flow path (Paragraphs 0027, 0028, 0034 and 0063-0065; Figures 1 and 2).
Yao teaches that the reference value is chosen to protect the anode, but gives merely a single example of 500 wt ppm, 0.05%, specifically citing this value as merely an example (Paragraph 0064). It would have been obvious to one of ordinary skill in the art at the time of filing to optimize this reference value, beyond the sole example given, in order to provide the degree of anode protection desired in view of the specific composition of the anode, operating conditions and the time required to initiate startup of the cell (MPEP 2144.05 II).
It would have been obvious to one of ordinary skill in the art at the time of filing that the start-up fluorine production would comprises entrained hydrogen fluoride as well as the downstream fluorine production (Paragraph 0034); however, Yao fails to specifically teach providing a mist removal or clogging suppression mechanism on the second flow path through which this start up fluorine production is sent.
However, Shodai also discusses the electrolysis of hydrogen fluoride to fluorine gas where HF mist is trapped from the outlet of the fluorine gas. Shodai teaches that the HF is removed from every flow path exiting the cell and that this removed HF gas is then returned to the electrolytic bath for further production of fluorine gas (Paragraph 0063; Figure 1). Therefore, it would have been obvious to one of ordinary skill in the art to provide the refining device of Yao on every exit path of the cell, including the second flow path/start-up path, in order to recover as much HF as possible for return to the cell as taught by Shodai. Thus an additional refining mechanism on the second flow path comprising a mist pool space acting as a clogging suppression mechanism formed downstream from a first portion of the second flow path.
As to claims 4, 7 and 8, the combination of Yao and Shodai teaches the methods of claims 1, 2 and 3. Yao further teaches that the electrolytic cell has a structure in which bubbles generated on an anode or a cathode used in the electrolyzing are capable of rising vertically in the electrolyte to reach a surface of the electrolyte (i.e., the anode and cathode are vertical, parallel to each other and perpendicular to the surface of the electrolyte) (Figure 1).
Claims 3 and 6 are rejected under 35 U.S.C. 103 as being unpatentable over the combination of Yao and Shodai as applied to claims 1 and 2 above, and further in view of US Patent Application Publication No. 2006/0219570 to Furuta et al. (Furuta).
As to claims 3 and 6, the combination of Yao and Shodai teaches the methods of claims 1 and 2. Yao teaches that the anode is carbon, but fails to give the specific type of carbon (Paragraph 0020). However, Furuta also discusses anodes for electrolytic fluorine generation and teaches an improved anode in terms of anode effect and sludge generation is an anode comprising diamond, graphite or an amorphous carbon (Paragraph 0001; Claim 2). Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to modify the anode of Yao with an anode as in Furuta, thus an anode comprising the carbon in the form of diamond, graphite or an amorphous carbon, in order to utilize an improved anode in terms of anode effect and sludge generation as taught by Furuta.
Claim 9 is rejected under 35 U.S.C. 103 as being unpatentable over Yao.
As to claim 9, Yao teaches a method for producing fluorine gas, the fluorine gas produced by electrolyzing an electrolyte (molten salt) containing hydrogen fluoride and a metal fluoride, potassium fluoride, the method comprising, electrolyzing the electrolyte in an electrolytic cell (1) and measuring a water concentration in an electrolytic cell (Paragraphs 0018, 0053 and 0054; Figure 1). Yao teaches that when the water concentration is measured higher than a reference value a fluid generated inside the electrolytic cell is sent from the inside of the cell to an outside of the cell through a flow path, corresponding to the second flow path of the claims, (branch passage (72)) and when the water concentration is measured lower than a reference value the cell start up is finished and normal operation proceeds wherein the fluid generated within the electrolytic cell inside is sent outside the cell via a another flow path, corresponding to the first flow path of the claims (main passage (15)), Yao thus teaching this operation occurs from a start of electrolysis (cell start up) at least until stable electrolysis starts (normal operation) (Paragraphs 0027, 0028, 0034 and 0063-0065; Figures 1 and 2).
Double Patenting
The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969).
A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b).
The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13.
The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer.
Claim 1-4 and 6-8 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-4 and 6-8 of copending Application No. 17/595,958 (reference application). Although the claims at issue are not identical, they are not patentably distinct from each other. The copending claims claim all the limitations of the present claims with the exception of a different numerical range for the reference value of oxygen content. It would have been obvious to one of ordinary skill in the art at the time of filing to optimize this reference value in order to provide the degree of anode protection desired in view of the specific composition of the anode, operating conditions and the time required to initiate startup of the cell (MPEP 2144.05 II).
This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented.
Response to Arguments
Applicant's arguments filed 27 February 2026 have been fully considered but they are not persuasive.
Applicants argue that Yao does not focus on the correlation between the water concentration and the particle size of the mist; however, this language is not present nor required by the claim. Applicants may have a different reason for performing the claimed method steps, however, Yao still meets the claim limitations.
Applicants further argue that Yao does not switch between flow paths, but stops the electrolysis. However, the Examiner disagrees, when the moisture content is higher than a reference, Yao conducts start up electrolysis and sends the product through bypass passage 72, start up electrolysis is then stopped and put in stand by mode wherein regular electrolysis is then started and the product is sent through main passage 15. Thus even though there is, or can be, a pause between start up electrolysis and regular electrolysis, there is still a switching between passages, and a corresponding measuring throughout cell start up (starting electrolysis) and stable electrolysis (stand by and normal operation).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to CIEL P Contreras whose telephone number is (571)270-7946. The examiner can normally be reached M-F 9 AM to 4 PM.
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/CIEL P CONTRERAS/Primary Examiner, Art Unit 1794
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