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 .
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.
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 1-4 are rejected under 35 U.S.C. 103 as being unpatentable over Saeki et al. (JP 2017-115188 A, using attached machine translation, “Saeki 2017”) in view of Saeki et al. (JP 2013-163180 A, using attached machine translation, “Saeki 2013”).
Regarding claims 1 and 3, Saeki 2017 teaches an electrode for generating chlorine from dilute salt water ([0001], [0008]). The electrode comprises a titanium or titanium alloy substrate, an intermediate layer, and a catalyst layer ([0010]). The intermediate layer comprises porous platinum and titanium oxide on the substrate ([0021]). The catalyst layer comprises 25 to 62 mol% platinum, 3 to 10 mol% iridium oxide, and 35 to 65% tantalum oxide in terms of the metal amount ([0010]).
Saeki 2017 does not teach the claimed catalyst layer consisting of 2 to 24 mol% platinum, 41 to 49 mol% iridium oxide, and 35 to 49 mol% tantalum oxide; nor the claimed polarity switching process with 5 to 60s intervals and a current density of 0.05 to 0.25 A/cm2; nor the use of such an electrode in an electrolytic cell comprising at least a pair of electrodes.
However, Saeki 2013 teaches another electrode for generating chlorine in water which also contains chloride ions ([0001]). The catalyst layer of this composite electrode comprises: at least 4 mol% platinum ([0007]); 37 to 57 mol% iridium oxide ([0007]); and at least 35 mol% and ideally 42 to 48 mol% tantalum oxide, ([0005]: “more than 35 mol% of tantalum oxide;” [0008]: ideal range). The electrode of Saeki 2013 is used in an electrolytic cell comprising two electrodes, and the polarity cycling results in both functioning as anodes and cathodes ([0012], Fig. 1).
The tantalum oxide range taught by Saeki 2013 is fully within the claimed range of 35 to 49 mol%. The iridium oxide range taught is broader than the claimed range of 41 to 49 mol%. The taught range of at least 4 mol% platinum is open-ended, however, the language of the present application’s claims 1 and 3, “consists of,” excludes unrecited elements and therefore the balance of the catalyst layer must be platinum so as to add up to 100 mol%. It is therefore obvious to one skilled in the art to arrive at an ideal mol% of platinum and iridium oxide through routine experimentation. It is not inventive to discover the optimum or workable ranges in this manner. See MPEP §2144.05(II). The ranges of 2 to 24 mol% platinum and 41 to 49 mol% iridium oxide as claimed would have been obvious through such routine experimentation.
While many embodiments of the Saeki 2013 electrode catalyst layer include rhodium oxide, it is not a required component ([0005]: “at least iridium oxide and tantalum oxide”). Saeki 2013 further teaches changing the polarity of the electrode every 5 seconds with a 1-second pause at a current density of 15 A/dm2, equivalent to 0.15 A/cm2 ([0030]). The time and current densities are within the claimed ranges of 5 to 60s and 0.05 to 0.25 A/cm2, respectively.
It would have been obvious to one of ordinary skill in the art as of the effective filing date to use the Saeki 2013 catalyst layer composition and electrolysis procedure in the electrode of Saeki 2017 to create the claimed invention, and to use the electrode in a cell as also shown by Saeki 2013. One would make such modifications with the expected result of improving the longevity and/or efficiency of the electrode.
Regarding claims 2 and 4, the preferred 42 to 48 mol% tantalum oxide range taught by Saeki 2013 ([0008]) and applied to claims 1 and 3 is fully within the claimed range of 37 to 48 mol%. It is also obvious to one skilled in the art to arrive at the narrower claimed ranges of 4 to 21 mol% of platinum and 42 to 48 mol% iridium oxide through routine experimentation. It is not inventive to discover the optimum or workable ranges in this manner. See MPEP §2144.05(II). The ranges of 2 to 24 mol% platinum and 41 to 49 mol% iridium oxide as claimed would have been obvious through such routine experimentation.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. US 2020/0055752 A1 to Hara et al. teaches an electrolysis device for production of hypochlorous acid. US 2022/0178034 A1 to Erman et al. teaches an electrode for electrolysis comprising a titanium substrate; intermediate layer; and tantalum oxide, ruthenium oxide, and platinum composite layer.
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/CBF/Examiner, Art Unit 1711
/MICHAEL E BARR/Supervisory Patent Examiner, Art Unit 1711
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