DETAILED ACTION
Status of Application
The Examiner acknowledges receipt of the amendments and arguments filed on 6/24/2026 wherein claims 24 and 44 have been amended.
Claims 24-44 are presented for examination on the merits. The following rejections are made.
Response to Applicants’ Arguments
Applicant’s amendments filed 6/24/2026 overcome the rejection of claims 24-44 made by the Examiner under 35 USC 103 over Gomez et al. (WO 2010/045280) in view of Wellinghoff et al. (US 2008/0026029), evidenced by Delcomyn et al. (Environ Sci Tech, 2006, 40, 2759-2764). This rejection is withdrawn as the references failed to suggest/describe a spray dried powder composition being free of moisture that could initiate chlorine dioxide release ‘before an optional desiccant is admixed with the light-activated spray-dried powder.’
New Rejections, Necessitated by Amendment
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 24-44 is/are rejected under 35 U.S.C. 103 as being unpatentable over Gomez et al. (WO2010/045280; of record) in view of Wellinghoff et al. (US 2008/0026029; of record) and Gray et al. (US 2005/0106380), evidenced by Delcomyn et al. (Environ Sci Technol, 2006, 40, 2759-2764).
Gomez describes a light-activated composition for releasing chlorine dioxide in an amount effective to provide a disinfection benefit. The composition may be in the form of a polymeric film (see page 4) (see instant claim 44)
The composition is to comprise a chlorite, such as sodium chlorite, in an amount of 0.01-50% by weight and a photocatalyst, such as a metal oxides like zinc oxide and titanium dioxide (rutile; see page 12), in an amount of between 50-99.99% by weight (see pages 4-5 and claims 4 and 11) (see instant claims 24, 30, 31-35).
Gomez teaches that their composition may comprise a light-filtering material such as silicates, aluminosilicates and borosilicates (see page 14) (see instant claims 28 and 29). Instant claim 29 identifies desiccants as including “a silicate, a borosilicate, an aluminosilicate…”. Thus, because the light filtering materials taught by Gomez are chemically the same as the chemical desiccants claimed, the silicates, borosilicates and aluminosilicates of Gomez must necessarily possess this property despite being unrecognized as such.
Although a product-by-process limitation, Gomez teaches that their composition is made by a process of spray drying a suspension of the photocatalyst and chlorite (see page 14). The spray drying is performed so as to remove solvent from the mixture which suggests that the resulting product is to be free of solvent (water/moisture). The spray drying process described by Gomez is performed in the dark using an inlet temperature of 250-350oC and an outlet temperature of 100-150oC (see page 15). Although the process of Gomez’s spray drying utilizes an inlet temperature slightly lower than that claimed (350 v. 482oC), it is sufficiently close that one of ordinary skill in the art would expect similar results.
Moreover, regarding instant claims 24 and 38-43 and the limitation that the claimed spray dried composition be prepared in the dark by a spray-drying process, be performed in an inert atmosphere, have a solution pH of 9-14, etc., these are product-by-process limitations. See MPEP 2113(I) which states that if the product in the product-by-process claim is the same as or obvious to a product of the prior art, the claim is unpatentable even though the prior product was made by a different process. In the present case, the prior art product is made by the same process (spray drying) with the differences in process being immaterial to the product produced, e.g. difference in inlet temperature as discussed above. It would be reasonable to expect the resulting spray dried formulation of Gomez to yield light-activated spray-dried powder that does not include a source of moisture that could initiate chlorine dioxide release similar to that being claimed.
Gomez fails to teach the sodium chlorite as having between 85-99% purity and fails to teach the spray dried powder as being free of moisture that could initiate chlorine dioxide release before an optional desiccant is admixed with the light-activated spray-dried powder.
Wellinghoff, like Gomez, is directed to energy-activated (via exposure to light) compositions for controlled release of chlorine dioxide (see claim 1) without the need for moisture (see [0008]) (see instant claim 37). The energy activated composition is made by spray-drying a solution (herein the ‘to-be spray dried solution’) that comprises a mixture comprising a catalyst, such as (rutile) titanium dioxide (see [0047]) (see instant claims 31-33), an anion source such as technical grade sodium chlorite (see [0037, 0081]) (see instant claim 25) (technical grade sodium chlorite 85% purity as required by instant claim 24 – see page 2760 of Delcomyn et al) and a surfactant such as an alkyl aryl ethoxylate and ethoxylated alkylphenol (nonionic) (see instant claims 26 and 27). Light-filtering agents, such as silicates (desiccant as defined by claims), are also contemplated for inclusion in the spray-dried powder (see [0052] and Example 8). The spray dried composition may be combined with polymers to form a final product (see [0059]) (see instant claim 44). Wellinghoff’s composition is to protected from moisture during production and storage so as to prevent premature gas generation and release (see [0007]).
The to-be spray dried solution may comprise water (as noted above), however, other solvents are contemplated such as water-miscible organic materials such as alcohols (e.g. methanol; see [0075]), ketones (e.g. acetone; see [0053]) and amides (e.g. dimethylformamide; see [0053]) (see instant claims 41-43). It is noted that ‘azeotrope’ as recited by instant claims 41-43 is a functional description and because the chemical compounds of the prior are the same as the chemical compounds specified in the claims, said compounds must have this property naturally. The pH of the to-be spray dried solution is taught as being from 10-11 (see Example 4) (see instant claims 39 and 40). However, it is important to note that the solvent selection and the pH for the spray drying process are process limitations by which the product is made and limit the method of making the composition rather than the composition itself. See MPEP 2113(I)
Regarding instant claim 36, Wellinghoff’s chlorite composition provides the following release profile for their energy-activated composition:
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197
416
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(Fig 18) wherein chlorine dioxide is seen as being released at a rate of 100 ppm/4 hours (no stabilizer and 1% stabilizer) which equates to about 0.42 ppm ClO2 per minute which is within rate of disinfection required. Additionally, the rate of chlorine dioxide release appears as a tunable property (see Figures 2-15). It would have been obvious to modify Gomez’s invention to exhibit a release profile similar to Wellinghoff with a reasonable expectation for success in imparting a desired rate of disinfection. See MPEP 2143(I)(A).
Gray, like Gomez and Wellinghoff, is directed to gas generating composition comprising an anion source, such as an alkali metal chlorite (see [0055]) and a activator such as titanium dioxide (see [0065]). The composition may be produced into a powder via spray drying (see [0085]). Gray teaches that the components of the composition release at least one gas (e.g. chlorine dioxide) upon exposure to moisture (see [0014]) and so the composition should be substantially free of water so as to not provide a pathway for premature release of gas (see [0082]). It is taught that insubstantial amounts of water can hydrolyze a portion of the acid releasing salt and so the goal should be a composition free of water. Thus, it would have been obvious to modify Gomez and Wellinghoff to follow the guidance of Gray to produce a powder material that is substantially free of water so as to mitigate premature gas release as this would ensure maximal gas release at the desired time point. See MPEP 2143(I)(D) which states that the application of a known technique to a known product ready for improvement to yield predictable result is supportive of an obviousness conclusion.
Therefore, the invention as a whole is prima facie obvious to one of ordinary skill in the art at the time the invention was filed, as evidenced by the references, especially in absence of evidence to the contrary.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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 extension fee 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 date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to KYLE A PURDY whose telephone number is (571)270-3504. The examiner can normally be reached from 9AM to 5PM.
If attempts to reach the examiner by telephone are unsuccessful, the examiner's supervisor, Bethany Barham, can be reached on 571-272-6175. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/KYLE A PURDY/Primary Examiner, Art Unit 1611
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