DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after 16 March 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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 24 February 2026, has been entered.
Status of Claims
The amendment, filed on 24 February 2026, is acknowledged.
Claims 4-5 are amended.
Claims 1-3 are cancelled.
Claims 4-5 are pending and under consideration in the instant Office Action.
Response to Amendments
Rejections withdrawn
Rejections pursuant to 35 U.S.C. § 102
The rejection of claims 1-3 under 35 U.S.C. § 102 set forth in the Office Action mailed on 11 September 2025, is moot in view of Applicant’s cancellation of the claims. The rejection of claim 5 under 35 U.S.C. § 102 set forth in the Office Action mailed on 11 September 2025, is withdrawn in view of Applicant’s amendment to the claim.
Rejections pursuant to 35 U.S.C. § 103
The rejection of claims 1-3 under 35 U.S.C. § 103 set forth in the Office Action mailed on 11 September 2025, is moot in view of Applicant’s cancellation of the claims. The rejection of claims 4-5 under 35 U.S.C. § 103 set forth in the Office Action mailed on 11 September 2025, is withdrawn in view of Applicant’s amendment to the claim and in favor of the new grounds of rejection below.
New Grounds of Objection
Claim Objections
Claim 4 is objected to because it recites “a pulse width of 1.5 mS or less” in line 11 (bold added for emphasis). The bolded unit, microsiemens, is a unit of electrical conductance (as used in line 5 of the claim); the capitalization of the “s” is believed to be an error and should be lower case, resulting in the unit microseconds (ms), which is consistent with a measure of pulse width.
Appropriate correction is required.
New Grounds of Rejection
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 4-5 are rejected under 35 U.S.C. 103 as being unpatentable over Holzer et al. (Plasma Chem. Plasma Process, 2008, 28, 1., hereafter referred to as Holzer) in view of Pupunat et al. (Efficient Reduction of Chemical Oxygen Demand in Industrial Wastewaters, CSEM Scientific and Technical Report, 2002, available on CSEM website, accessed via Wayback Machine, hereafter referred to as Pupunat), Nihon Spindle Manufacturing Co. LTD. (U.S. Patent Application Publication No. US 2017/0275187 A1, published on 28 September 2017, provided by Applicant in the IDS filed on 16 November 2022, hereafter referred to as NSM), and Park et al. (Appl. Phys. Lett. 2000, 76 (3), 288., hereafter referred to as Park).
Holzer teaches a hybrid pulsed electrical discharge reactor which utilizes various electrode needles to produce hydrogen peroxide following high voltage discharges (Abstract). Oxidation technologies which produce oxygen containing reactive species are taught to be a current focus of research and industry because of their high reaction rates, with a specific focus on “efficient production and utilization of OH radicals either for oxidizing organic compounds or killing microorganisms” (Introduction, para. 1). Holzer further teaches the erosion of electrodes due to high current electrical discharge, indicating that parts of the metal high voltage electrodes are in the aqueous solution (pg. 4, H2O2 Formation Studies with Different Needle Electrode Materials, para. 1). In the case of tungsten electrodes, it was “postulated that either tungsten particles or tungstate ions (WO42-) released into the solution caused the decomposition of H2O2 by catalytic reactions” (pg. 6, para. 3).
The “stationary state” of a nanoparticle catalyst is interpreted, in view of lines 7-9 of pg. 14 of the instant specification, to be a state in which a voltage is not being applied across electrodes to generate plasma. As a result, the sterilizing liquid of instant claim 4 comprising reactive oxygen species (ROS) and a nanoparticle catalyst in a stationary state is interpreted to be a sterilizing liquid that possesses ROS and a nanoparticle catalyst in the absence of an applied voltage. Holzer teaches such a sterilizing liquid, as demonstrated by the presence of ROS and tungsten nanoparticles in the absence of an applied voltage (Fig. 3 and pg. 6, para. 3). The water used to create the sterilizing liquid is taught to be deionized, adjusted to a conductivity of 180 mS/cm with KCl and a pH of 4.4, and circulated at a rate of ~ 1 L/min (Holzer, Experimental, page 3).
The instant specification defines “immediately after production of the sterilizing liquid” to mean “within a few minutes after production of the sterilizing liquid” (pg. 3, lines 12-14). Holzer teaches the production of H2O2 via operation of a corona, which is generated via electrical discharge from electrodes (vide supra). Examination of Fig. 3 of Holzer demonstrates the presence of H-2O2 when the corona is off and the nanoparticle catalyst is in a stationary state. Further, Table 1 and para. 3 of pg. 6 teach that tungsten nanoparticles are present in the solution immediately upon operation of the corona, and the tungsten nanoparticles would persist in solution after turning off the corona to enter a stationary state.
In Figure 3 and Table 1 on page 5, Holzer teaches the rate of H2O2 formation and electrode erosion rate for different electrode materials. In the case of tungsten copper electrodes, which are taught to be 90% W and 10% Cu w/w (Experimental, pages 2-3), H2O2 is formed at a rate of 0.476 mmol/s, which in a 0.6 L reactor volume is 0.02697 ppm/s, and the electrode erodes at a rate of 3.46 mg/s, which is 0.00519 ppm/s tungsten particles released into solution. To reach a level of 16 ppm tungsten particles in solution at a rate of 0.00519 ppm/s, the reactor would need to operate for ~3083 s or 51 min 23 s, at which point ~83 ppm H2O2 would be formed. Figure 3 demonstrates that a reactor containing the above electrode was operated until the 60-minute mark, indicating that such a solution was created by Holzer.
Holzer further teaches that “cavitational forces due to formation of microbubbles close to the electrode tip” resulted in corrosion (H2O2 Formation and Electrode Erosion Using a Hypodermic Stainless Steel Needle Electrode, page 10). Holzer attempted to reduce this in the case of stainless steel hypodermic needles via flow of O2 gas through the needle, but found that erosion only decreased considerably at high flow rates, which also reduced H2O2 production (page 11, paragraphs 2-4 and Table 3).
Finally, Holzer taught that the voltage was increased in accordance with experimental conditions to maintain a stable discharge (pg. 9, H2O2 Formation and Electrode Erosion Using Electrodes with Different Diameters). The instant specification states in para. [0151] that if the voltage across the electrodes, considered to be the pulse voltage (para. [0012], [0046], etc.), drops below the inception voltage, the probability of plasma not to be produced increases. Because Holzer explicitly states that the voltage should be monitored to ensure stable plasma discharge, this is considered equivalent to maintaining a pulse voltage that is equal to or greater than the discharge inception voltage.
Guidelines on the obviousness of similar and overlapping ranges, amounts, and proportions are provided in MPEP § 2144.05. With respect to claimed ranges which “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990). These guidelines apply to the water conductivity and ROS and catalyst concentration taught by Holzer; in each instance, the values taught by Holzer fall within the ranges recited in the instant application.
Holzer does not teach the COD of the water sterilized, the cavitation to be caused by a rotor-driven stirrer, the pulse width to be ≤1.5 microseconds, nor the pulse repetition frequency to be ≥100 kHz. These deficiencies are offset by the teachings of Pupunat, NSM, and Park.
Pupunat teaches an invention for electrochemical treatment of wastewater (paragraphs 1-3, Figures 1-3). In Switzerland, the country in which the company CSEM is based, the safe levels of chemical oxygen demand (COD) for industrial wastewater to be released back into the environment is 200-1000 ppm (1st paragraph).
NSM teaches a method of sterilizing liquids by causing cavitation and generating plasma (Abstract and claim 1). NSM teaches the cavitation to be caused by stirring the liquid to be sterilized with a rotary blade which is housed in a casing (Fig. 3, para. [0047-0049], and claim 1). The rotary blades rotate about a central axis, labeled “A3” in Fig. 3, which is in the center of the housing (“1” in Fig. 3) and are therefore considered to be concentric with respect to the housing. Cavitation caused by stirring with rotary blades is taught by NSM to overcome issues associated with other methods of causing cavitation, such as “small” sterilizing power and “a sterilizing effect [that] cannot be easily obtained”, or enlarged apparatus size to accommodate greater sterilizing power (para. [0018-0022]). In particular, cavitation caused by stirring the rotary blades as in the invention of NSM is taught to produce “fine air bubbles” which allow for plasma to be efficiently and uniformly generated with a small-sized apparatus producing a great sterilizing effect (para. [0026]).
Park teaches a method of producing plasma under atmospheric pressure conditions using radio frequency power (Abstract). Traditional plasma generation devices utilize low-pressure, requiring vacuum operation which is expensive and complicated in addition to limiting materials processing capabilities (pg. 288, left col., para. 1). Conversely, plasma generation devices that work at atmospheric pressure can eliminate complications introduced by vacuum operation, allowing them to work in applications including “ozone production for water purification” (pg. 288, left col., para. 2). Using a system with coupled electrodes, Park produces a stable discharge plasma at atmospheric pressure using 13.56 MHz radio frequency (rf) at relatively low temperatures (50-300 °C) without arcing (pg. 288, left col., para. 3). Fig. 1(d) demonstrates that the full duration at half maximum (FDHM) of the pulse is ~40 ns and the full width at zero intensity (FWZI) is ~75 ns. The instant specification does not state how the pulse width is assessed, but both values above are less than 1.5 microseconds and are interpreted as within the range recited in instant claim 4. Finally, Park teaches that their operating conditions produce “a large concentration of oxygen atoms”, different from traditional plasma sources, and would be useful for materials applications (pg. 289, right col., para. 1 and pg. 290, right col., para. 1-2).
It would have been prima facie obvious to a person of ordinary skill in the art, prior to the filing date of the instant application, to combine the teachings of Holzer, Pupunat, NSM, and Park to arrive at the claimed invention because combining prior art elements according to known methods yields predictable results. One would be motivated to combine the teachings of Pupunat with those of Holzer because the hybrid reactor producing a sterilizing liquid taught by Holzer does not disclose all properties known in the art of the water utilized. While the water is described as deionized, adjusted to a conductivity of 180 mS/cm with KCl, and at pH 4.4, the COD is not taught (Holzer, Experimental, page 3). Pupunat teaches a range of values for COD, falling within the range of instant claim 4, that is acceptable for water entering the environment. An ordinary artisan would be motivated to use water in a sterilizing liquid that is environmentally safe.
In view of the teachings of NSM, one of ordinary skill in the art would be motivated to create cavitation using a stirrer driven by a motor because NSM teaches this method to produce fine air bubbles which allow for plasma to be efficiently generated, resulting in a solution with great sterilizing effect without requiring a large apparatus. The ordinary artisan would desire an alternative method of producing cavitation because Holzer teaches that their method, flowing O2 through needle electrodes, reduced ROS production, which the artisan would recognize as undesirable. The person of ordinary skill would be motivated to use the specific method of NSM because the reference teaches that cavitations resulting from stirring meets Holzer’s objectives of producing sterilizing liquid with plasma without an undesirable reduction in ROS concentration.
Finally, one of ordinary skill would be motivated to use the electric pulse parameters taught by Park in the invention of Holzer because Park teaches their method to produce a stable plasma at low temperatures and ambient pressure without arcing, which an ordinary artisan would recognize as desirable in a plasma generating device. Further, Park teaches that their parameters produce a higher concentration of oxygen atoms, which the ordinary artisan would recognize as a ROS and as capable of producing other ROS, which in turn are desirable in sterilizing liquids.
The properties of the sterilizing liquid recited in claim 5 arise from the composition of the sterilizing liquid. Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). See MPEP § 2112.01. "Products of identical chemical composition cannot have mutually exclusive properties." In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990). A chemical composition and its properties are inseparable. Therefore, if the prior art teaches the identical chemical structure, the properties applicant discloses and/or claims are necessarily present. Id. Therefore, because Holzer teaches the sterilizing liquid containing ROS and a nanoparticle catalyst at the concentrations recited in instant claim 4, the sterilizing effect is necessarily present. As a result, there is a reasonable expectation of success in arriving at the invention of claims 4-5 in view of the teachings of Holzer, Pupunat, NSM, and Park.
Response to Arguments
Applicant's arguments filed on 24 February 2026, have been fully considered but they are not persuasive. In the para. that spans the bottom of pg. 4 and top of pg. 5, Applicant argues that the Holzer reference teaches a pulse frequency of 60 Hz and a conductivity of 180 mS/cm, which are different than the limitations in amended claim 4. The limitations in instant claim 4 specify a water conductivity of 2000 mS/cm or less and 180 mS/cm is less than 2000 mS/cm, therefore the argument is not found to be persuasive. The pulse frequency of 100 kHz or greater has been rendered obvious above and this argument is also not found to be persuasive.
Conclusion
No claims are allowed.
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/S.J.S./
Examiner, Art Unit 1619
/TIGABU KASSA/Primary Examiner, Art Unit 1619