FINAL ACTION
Response to Arguments
Applicant's arguments filed March 23rd, 2026 have been fully considered but they are not persuasive.
Applicant argues that:
Li does not provide any teachings of either the inlet end or outlet end of the UV-C treatment chamber being closed by an expanded polytetrafluoroethylene filter configured to reflect UV-C radiation within the UV-C treatment chamber. Pages 4-5 of the Office Action appear to suggest the inlet end of the UV-C treatment chamber is closed by "air passing UV light absorption component 112 coated with nano particles of metal oxide semiconductor with or without metal nanoparticles." See Li, para. [0026]. Applicant respectfully disagrees. The 112 component in Li is a UV light absorption component, not a reflective component. UV light absorption component 112 corresponds to UV light absorption filter 203 in paragraph [0029] and to the component 300 described in paragraphs [0030] and [0031] of Li. Notably, Li teaches that "The processes at 203 can enhance each other while the UV light gets absorbed by various physical processes" [emphasis added].
Additionally, Li teaches that the component 420, which corresponds to component 300, will absorb the "extra UV light." See Li, para. [0032]. Li further teaches that the component 520, which corresponds to component 300, will absorb the "extra UV light." See Li, para. [0033]. Thus, the UV light absorption component 112 does not provide any teaching of an expanded polytetrafluoroethylene filter configured to reflect UV-C radiation within the UV-C treatment chamber, as currently recited in claim 1.
The Examiner would respectfully respond that:
It is the position of the Office that Li discloses these teachings. Li clearly states in paragraph 30 that:
FIG. 3 shows an embodiment of a component coated with Nano particles of metal oxide mixed with electrically isolated nanoparticles of Aluminum, Gallium (Ga) or other previous metal for plasma enhanced UV light absorption and locally enhanced UV cleaning. This represents as the component 112 in FIGS. 1 and 203 in FIG. 2. As shown, the component 300 is coated with mixture of nanoparticles, which includes metal oxide 301 and precious metal 302…The component 300 can be made by UV highly reflective and low UVC/B absorptive solid film or porous film.
In which, paragraph 28 discloses that materials with high reflection and low absorption for UVC/B light utilized in the invention is expanded polytetrafluoroethylene. It is the position of the Office that the nanoparticles provided on the filter component (112/203/300) are what absorbs UV light in order to produce the hydroxyl radicals shown in Figure 3. The component itself (112/203/300) is highly reflective according to the teachings of Li as noted above.
As such, Li clearly discloses that component (112) is made from expanded polytetrafluoroethylene in paragraph 28, and clearly discloses in both paragraph 28 & 30, that said component (112) is highly reflective towards UVC light; in which said component captures bioaerosols and dangerous viruses in the airflow, thus constituting a filter (Abstract; paragraph 29).
Therefore, this response is not persuasive.
The Applicant also argues:
Further, Li does not provide any teaching or suggestion of the inlet end of the UV-C treatment chamber being closed by an expanded polytetrafluoroethylene filter configured to reflect UV-C radiation within the UV-C treatment chamber [emphasis added]. Li teaches that "the arrangement and exact location of" the components including the UV light absorption component 112 "can be varied along the air flow pipeline 101" of the system. See Li, para. [0026]. As such, Li teaches that the UV light absorption component 112 (UV light absorption filter 203, component 300, 420, 520) is not intended to "close" an end of the UV-C treatment chamber.
The Examiner would respectfully respond that:
The teachings of Li concerning that “the arrangement and exact location of” the component (112) “can be varied along the air flow pipeline 101” simply means that filter (112) can be moved forward or backward within pipeline (101) and does not have to be located in the exact location as shown in Figure 1. Nonetheless, Li discloses in Figure 1 that said filter (112) is located at the “inlet end”, in which said filter must necessarily “close” off said inlet end at least partially. It is unclear how the filter (112) placed within pipeline (101) would not at least partially close off the inlet end.
More specifically, the “inlet end” can be reasonably defined as all of the components at the beginning of the flow path, and the “outlet end” can be reasonably defined as all of the components at the end of the flow path, wherein the UV-C treatment chamber is located between the “inlet end” and “outlet end” as shown below.
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Because the filter (112) is located at the “inlet end” as shown above, and must necessarily at least partially close off said inlet end, then the disclosure of Li meets these limitations.
As such, this response is not persuasive as well.
Applicant continues to argue that:
In relation to the outlet end, Li teaches "an optional activated carbon filter 113 near the air outlet 106 to eliminate any possible of a small amount of ozone generated by UV light when it interacted with oxygen molecules in the air flow." Such a filter is not configured to reflect or otherwise interact with the UV-C radiation within the UV-C treatment chamber, contrary to the requirement in present claim 1.
The Examiner would respectfully respond:
Li is not utilized for this teaching, as the Office Action (Office Action filed September 23rd, 2025) denotes that Li does not disclose a filter at the outlet end configured to reflect or otherwise interact with the UV-C radiation. The reference of Clark is utilized for this teaching as set forth below (and in Office Action filed on September 23rd, 2025).
Finally, the Applicant argues that:
Li teaches away from the claimed features of closing the inlet and/or outlet with an expanded polytetrafluoroethylene filter configured to reflect UV-C radiation within the UV-C treatment chamber. As explained above, Li teaches absorbing UV light within the UV-C treatment chamber, thus reducing the quantity of UV light therein.
Therefore, a skilled artisan would not have been motivated to modify the teachings of Li in view of Clark to close the outlet end with an expanded polytetrafluoroethylene filter configured to reflect UV-C radiation within the UV-C treatment chamber. The modification proposed in the Office Action would lead to an opposite effect from the purpose sought by Li (e.g., absorbing UV light and reducing the quantity of UV light), rendering Li's product inoperable for its intended purpose.
The Examiner would respectfully respond that:
As noted above, Li teaches that filter (112) at inlet end is highly reflective to UV-C light, and thus configured to reflect UV-C radiation with the UV-C treatment chamber. Thus, Li does not provide a teaching of “absorbing UV light” within the UV-C treatment chamber, and certainly does not state that it is critical to “absorb UV light”. The nanoparticles on filter (112) absorbs the UV light in order to produce hydroxyl radicals, but the filter itself is “highly reflective” as set forth in paragraphs 28 and 30 of Li. Thus, the proposed modification of Li with Clark as set forth below would not render Li’s product inoperable for its intended use because Li discloses that the pipeline (101) is “highly reflective” (paragraphs 26 & 28), and that the filter (112) is made from “highly reflective” material (paragraphs 28 & 30); and therefore one of ordinary skill would be naturally inclined to provide the outlet end with an expanded polytetrafluoroethylene filter as well in order to maximize the reflectivity of the UV light in the chamber to provide the desired kill rate of pathogens while minimizing power consumption and size of the unit due to the teachings of Clark. See paragraphs 4-12, 86, 87, 107, 108, 183 and 184 of Clark.
As such, the combination is proper, and the modification would operate as intended. Therefore, this response is not persuasive.
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.
Claims 1, 3-5, 15 and 16 are rejected under 35 U.S.C. 103 as being unpatentable over Li et al. (U.S. Publication No. 2021/0379234) in view of Clark et al. (U.S. Publication No. 2008/0152548).
Concerning claims 1 & 16, Li discloses an air sterilization unit and a method of sterilizing air using the air sterilizing unit, said air sterilizing unit comprising:
A housing (Figure 1) providing an air inlet (102) and an air outlet (106) and containing:
A filter module (105) located between the air inlet and the air outlet;
A UV-C treatment chamber (after device 103) located between the air inlet and the air outlet (Figure 1) and containing at least one UV-C radiation source (107); and
A ventilation system (103) located between the air inlet and the air outlet, configured to cause air flow into the housing through the air inlet, through the filter module and the UV-C treatment chamber and out of the housing through the air outlet (paragraph 26);
Wherein the UV-C treatment chamber (after device 103) comprises an inlet end (at 112), an outlet end (at 113) and a wall therebetween and the inlet end is closed with a first expanded polytetrafluoroethylene filter configured to reflect UV-C radiation within the UV-C treatment chamber (paragraphs 28 & 30), and the wall is provided with an expanded polytetrafluoroethylene liner (paragraphs 26 & 28), such that the UV-C radiation source is surrounded with expanded polytetrafluoroethylene for reflection of UV-C radiation within the chamber for destruction of pathogens in the air (paragraphs 26-28).
Li does not appear to disclose that the outlet end is closed with a second expanded polytetrafluoroethylene configured to reflect UV-C radiation within the UV-C treatment chamber. Clark discloses an air sterilization unit that includes a housing with an inlet and outlet, and a UV-C treatment chamber containing a UV-C radiation source located between the inlet and the outlet (Abstract; paragraphs 6-14). The reference continues to disclose that the outlet end is closed with an expanded polytetrafluoroethylene filter configured to reflect UV-C radiation within the UV-C treatment chamber (paragraphs 86, 87, 107, 108, 183 and 184; Figures 3, 5 and 23) in order to maximize the reflectivity of the UV light in the chamber to provide the desired kill rate of pathogens while minimizing power consumption and size of the unit (Abstract; paragraphs 4-12). Thus, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to include a second expanded polytetrafluoroethylene filter at the outlet end configured to reflect UV-C radiation within the UV-C treatment chamber in Li in order to maximize the reflectivity of the UV light in the chamber to provide the desired kill rate of pathogens while minimizing power consumption and size of the unit as exemplified by Clark.
Therefore, claim 1 is not patentable over Li in view of Clark.
Concerning claims 3 & 4, Li discloses that the filter module (105) is located outside the UV-C treatment chamber (after device 103) in which said filter module (105) is located between the air inlet of the housing and the inlet end of the UV-C treatment chamber as shown in Figure 1.
With respect to claim 5, although Li does not appear to disclose that the filter module comprises a plurality of filters, The Manual of Patent Examining Procedures discloses that in In re Harza, 274, F.2d 669, 124 USPQ 378 (CCPA 1960), a mere duplication of parts for a multiplied effect has no patentable significance unless a new and unexpected result is produced (See MPEP 2144.04). As such, the claiming of more than one filter in the module as set forth in claim 5 does not create a patentable distinction over Li. Thus, claim 5 is not patentable over Li in view of Clark as well.
Regarding claim 9, as broadly defined, Li continues to disclose that the filter module comprises a UV-A treatment chamber (102), as chamber (102) is configured to have an UV-A source placed therein an operate as a UV-A treatment chamber (Figure 1).
Concerning claim 15, Li modified by Clark also discloses an air sterilization unit that is configured to achieve an 8-log reduction of pathogens in the air (Figure 1; paragraphs 6-18 of Li; paragraphs 12-21 of Clark).
Thus, claim 15 is not patentable over Li in view of Clark as well.
Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Li et al. (U.S. Publication No. 2021/0379234) in view of Clark et al. (U.S. Publication No. 2008/0152548) as applied to claim 1 above, and further in view of Davis (U.S. Publication No. 2016/0271288).
Li is relied upon as set forth above. Li does not appear to disclose that the average UV-C radiation fluence within the UV-C treatment chamber is greater than 30,000 µJ/cm2. Davis discloses an air sterilization unit that includes a housing with an inlet and outlet, and a UV-C treatment chamber containing a UV-C radiation source located therein (Abstract and paragraph 8; Figures 1 & 2). The reference continues to disclose that the average UV-C radiation fluence within the UV-C treatment chamber is greater than 30,000 µJ/cm2 because such a fluence effectively sterilizes all bacteria, protozoa and viruses at a 99.9999% level (paragraph 10). Thus, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to provide an average UV-C radiation fluence within the UV-C treatment chamber of Li at greater than 30,000 µJ/cm2 because such a fluence effectively sterilizes all bacteria, protozoa and viruses at a 99.9999% level as exemplified by Davis.
Thus, claim 2 is not patentable over modified Li in view of Davis.
Claims 5-7 are rejected under 35 U.S.C. 103 as being unpatentable over Li et al. (U.S. Publication No. 2021/0379234) in view of Clark et al. (U.S. Publication No. 2008/0152548) as applied to claim 1 above, and further in view of Laseur et al. (U.S. Publication No. 2022/0096702).
Concerning claims 5-7, Li is relied upon as set forth above. Li does not appear to disclose that the filter module comprises a plurality of filters in which said plurality of filters comprises a HEPA filter doped with silver ions that traps contaminants in the air of a size up to 0.3 microns. Laseur discloses an air sterilization unit that includes a housing with an inlet and out, a UV-C radiation source located in the housing, and a filter module located between said inlet and outlet (Abstract; paragraphs 4-6; Figures 1E & 4). The reference continues to disclose that the filter module comprises a plurality of filters in which said plurality of filters comprises a HEPA filter doped with silver ions that traps contaminants in the air of a size up to 0.3 microns in order to intake air from different areas and rid said air of particulates that clog the unit, as well as aid in the destruction of pathogens (paragraphs 5, 29, 30, 36 and 44). As such, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to provide the filter module of Li with a plurality of filters in which said plurality of filters comprises a HEPA filter doped with silver ions that traps contaminants in the air of a size up to 0.3 microns in order to intake air from different areas and rid said air of particulates that clog the unit, as well as aid in the destruction of pathogens as exemplified by Laseur. Note that the HEPA filter disclosed in Laseur, which traps contaminants in the air of a size up to 0.3 microns, will also meet the limitations of a mesh filter that traps contaminants in the air of a size in the range of 3-10 microns as set forth in claim 6.
As such, claims 5-7 are not patentable over modified Li in view of Laseur.
Claims 5 and 8 are rejected under 35 U.S.C. 103 as being unpatentable over Li et al. (U.S. Publication No. 2021/0379234) in view of Clark et al. (U.S. Publication No. 2008/0152548) as applied to claim 1 above, and further in view of Liang et al. (U.S. Publication No. 2021/0283296).
Li is relied upon as set forth above. Li does not appear to disclose that the filter module comprises a plurality of filters in which the plurality of filters comprise an activated carbon filter. Liang discloses an air sterilization unit that includes a housing with an inlet and outlet, a UV radiation source located therein, and a filter module located between said inlet and outlet (Figures 1 & 2). The reference continues to disclose that the filter module comprises a plurality of filters in which the plurality of filters (paragraphs 8-12 and 37) comprise an activated carbon filter in order to capture gaseous pollutants from the air (paragraph 22). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to provide the filter module of Li with a plurality of filters in which the plurality of filters comprise an activated carbon filter in order to capture gaseous pollutants from the air as exemplified by Liang.
Thus, claims 5 and 8 are not patentable over modified Li in view of Liang.
Allowable Subject Matter
Claims 10-14 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.
Conclusion
THIS ACTION IS MADE FINAL. 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 KEVIN C JOYNER whose telephone number is (571)272-2709. The examiner can normally be reached Monday-Friday 8:00AM-4:30PM.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, MICHAEL MARCHESCHI can be reached at (571) 272-1374. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/KEVIN JOYNER/Primary Examiner, Art Unit 1799
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