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 .
Status of the Claims
Amendments to the Specification, Amendments to the Claims and Arguments/Remarks filed 16 December 2025, in response to the Office Correspondence dated 22 September 2025, are acknowledged.
The listing of Claims filed 16 December 2025, have been examined. Claims 1, and 4-18 are pending. Claims 1-3, and 8-9 have been amended and are supported by the originally-filed disclosure. Claims 2 and 3 are canceled and new claims 10-18 have been added.
Information Disclosure Statement
The Information Disclosure Statement (IDS), filed 16 December 2025, is acknowledged and has been considered.
Response to Amendment
The proposed amendment to ¶[0032] of the specification, correcting a typographical error (replacement of “[water]]oil” with “oil”), has been reviewed. The correction of the typographical error is supported by the original disclosure (see original ¶[0032] and FIG. 2). Entry of this amendment is permitted, as it constitutes a clerical correction that does not introduce new matter under 35 U.S.C. § 132(a), and accordingly, has been entered. The amended claims filed in the applicant’s reply are entered.
Several claims rely heavily on intended results (e.g., promoted reaction, eco-friendly effect, stable loading) rather than affirmative technical limitations. Based on the amended/newly cited limitations new grounds of rejection under 35 U.S.C. § 112(b) are issued, as detailed below.
The applicant's arguments regarding the rejections under 35 U.S.C. § 103 have been fully considered. However, for the reasons set forth below in the Response to Arguments, the arguments are not persuasive in establishing patentability. Newly added claims 10-18 have also been rejected under 35 U.S.C. § 103 based on the art which was previously cited, as it reads on the amended/newly cited limitations.
Maintained Rejections
The following rejections are maintained from the previous Office Correspondence dated 22 September 2025, since the art which was previously cited continues to read on the amended/newly cited limitations.
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, 8 and 9 are rejected under 35 U.S.C. § 103 as being unpatentable over Lee et al. (KR100306221B1; published 21 March 2002), hereinafter referred to as Lee, and Lee Chol-Tae et al. (KR20160064906A; published 28 November 2014), hereinafter referred to as Lee Chol-Tae, in view of Yang et al. (Yang CH, Huang KS, Chang JY. Manufacturing monodisperse chitosan microparticles containing ampicillin using a microchannel chip. Biomed Microdevices, (2):253-9; published 09 April 2007), hereinafter referred to as Yang.
Regarding instant claims 1 and 9, Lee teaches a method for producing biodegradable chitosan membrane microcapsules a using predetermined ratios of an aqueous phase chitosan polymer emulsion that is mixed to with an oil phase emulsion solution of sorbitan monooleate (wherein sorbitan monooleate acts as both an oil and a surfactant) that is then reacted by mixing with a aqueous crosslinking agent emulsion, creating capsule walls by interfacial reaction followed by washing, separating by centrifugation and drying by lyophilization to obtain microcapsules [droplets] (claims 1-6) having a predetermined size range of 0.5 to 40 μm (page 3, ¶ 8).
While not explicitly outlined, the crosslinking emulsion containing 0.5 to 10% by volume of sulfuric acid and 1 to 50% by volume of a 25% glutaraldehyde solution described by Lee (claim 1) would necessarily require a surfactant to create the initial stable emulsion (e.g., such as polysorbates, sorbitan esters or block co-polymers).
Lee Chol-Tae teaches mixing a predetermined ratio of oil and surfactant and mixing a predetermined ratio of the water phase chitosan solution with a second surfactant, followed by mixing the cross-linking agent of tripolyphosphate (TPP) after forming multiphase emulsion by homogenization with the oil/water/oil emulsion to form microcapsule droplets (Drawing).
Lee and Lee Chol-Tae do not teach the method using a microfluidic chip to dispose the phases at a predetermined flow ratio to mixing site.
Yang teaches using T-junction capillary cross-flow design microfluidic chips to generate monodisperse chitosan droplets and to control droplet diameter by adjusting flow ratios/flow rates (page 1, Abstract).
Regarding instant claim 8, Yang teaches chitosan microparticle size control based on flow rate (page 256-258, section 3.3), but does not explicitly disclose a flow ratio between the water phase and oil phase ranging from 1 to 5-20 and a droplet diameter size-adjustable within 50 μm. However, Fig.5 (page 257) exemplifies a 0.1 mL/minute water phase and 0.1 mL/min oil phase flow rate for diameter size control yielding a flow rate ratio between the two of 1, encompassed within the instant claimed range. The uniformity of the size distribution using the method described by Yang is clear from the Fig. 5 error bars (also noted to vary less than 5%, see Abstract; 400 ± 10 μm as noted in page 257, Fig. 4 legend) and diameter size adjustments within 50 μm based on changing the flow rate ratio between the oil and water phases is demonstrated (i.e., changing the oil flow rate from 0.4, 0.7 or 1.0 mL/min).
It would have been prima facie obvious to one of ordinary skill in the art prior to the instant effective filing date to use a microfluidic droplet generator to make the emulsion templates in preparing the invention of Lee and Lee Chol-Tae because Yang teach that microfluidic chips can produce monodisperse chitosan droplets and that droplet size is controlled by flow ratios, which would be a routine substitution of Lee and Lee Chol-Tae’s bulk stirring emulstification method with microfluidic droplet generation to gain improved monodispersity and predictable size control with a reasonable expectation of success.
Although the precise range of a 1 to 5-20 flow rate ratio of the phases is not explicitly disclosed by Yang, size adjustable within 50 µm would make such size control obvious from the teachings of Yang as a matter of optimization by routine experimentation, rendering instant claim 8 obvious.
The combined teachings of Lee, Lee Chol-Tae and Yang supply all the limitations of instant claim 1 (i.e., microfluidic chip movement, chitosan water phase, oil and surfactant phases, emulsion formation, crosslinking reaction to form beads, and size control) and instant claim 9 claims capsule obtained from the method rendered obvious under the above combinations of instant claim 1 being obvious (product by that method is also obvious). A skilled artisan, knowing the bulk emulsified interfacial chitosan microcapsules taught by Lee would see from Yang that microfluidic droplet generation yields better size control and could substitute bulk stirring with chip flow to provide “predetermined flow ratio” and “droplet size control.”
Claims 1, 4 and 6 are rejected under 35 U.S.C. § 103 as being unpatentable over Lee et al. (KR100306221B1; published 21 March 2002), hereinafter referred to as Lee and Lee Chol-Tae et al. (KR20160064906A; published 28 November 2014), hereinafter referred to as Lee Chol-Tae, in view of Yang et al. (Yang CH, Huang KS, Chang JY. Manufacturing monodisperse chitosan microparticles containing ampicillin using a microchannel chip. Biomed Microdevices, (2):253-9; published 09 April 2007), hereinafter referred to as Yang, and in further view of Ren and Zhang (Ren X, Zhang Y. Switching Pickering emulsion stabilized by Chitosan-SDS complexes through ion competition. Colloids and Surfaces A: Physicochemical and Engineering Aspects, volume 587, 2020, 124316; electronically published 05 December 2019), hereinafter referred to as Ren.
Lee, Lee Chol-Tae and Yang teaches the limitations of instant claim 1 (as described above), from which instant claim 4 depends, however does not teach specific limitations of instant claim 4.
Regarding instant claim 4, Lee and Lee Chol-Tae teach generating oil and water phase emulsions by mixing followed by the production of microcapsule [droplets] by reacting with a cross-linking agent, as described above. Lee Chol-Tae also teaches if the crosslinking rate of chitosan is too fast, encapsulation is adversely affected (page 2, next to last paragraph, last two lines), indicating the importance of controlling/tuning the rate of the cross-linking reaction for optimal results. However, Lee and Lee Chol-Tae do not explicitly teach phase inversion of the first surfactant or wherein the cross-linking agent is promoted by the phase-inverting.
Ren further teaches using chitosan surfactant systems with switchable stabilizer behavior, generating oil emulsification at an interface between the emulsion and the water phase solution and phase-inversion (Abstract). Ren teaches the preparation of dispersions by mixing cosmetic oil (isopropyl tetradecanoate) with the surfactant SDS alone at defined ratios or with chitosan (page 3, section 3.1 and Fig. 1(c)). The switchable emulsions generated by Ren rapidly destabilized upon the introduction of a competitive ion (CTAB) (page 7, section 4), thus in which one skilled in the art would be promoted to stabilize by cross-linking when the desired emulsion product has been achieved. Ren shows that surfactant switching changes stability and interfacial behavior (Abstract), which may affect reaction or shell formation speed.
While mixing of a second surfactant in the water-phase crosslinker or the speed of cross-linking reactions is not explicitly mentioned by Ren, it would have been predictable to a skilled artisan that using different surfactants or adjusting conditions can change interfacial surfactant coverage at droplet surfaces and stability which would impact subsequent crosslinking reactions.
Regarding instant claim 6, Lee Chol-Tae teaches moving the oil in the water phase emulsion by mixing to the interface of a second surfactant of mixture 2 (Span 80) and curing the o/w/o droplets by cross-linking with continuous mixing at 9000 rpm for 60 minutes to precipitate microcapsule droplets (Drawing).
It would have been prima facie obvious to one of ordinary skill in the art prior to the instant effective filing date to use the surfactant phase inversion mechanisms taught by Ren in the emulsions with surfactants followed by crosslinking taught by Lee and Lee Chol-Tae. One would be motivated to adopt the techniques taught by Ren using dual surfactants or adjusting conditions to change interfacial surfactant coverage or drive phase inversion switching at droplet surfaces and include a second surfactant in the water phase crosslinker and choose ratios to optimize stability and reaction kinetics with a reasonable expectation of success. A skilled artisan would expect to combine these, to put a surfactant in oil phase, a different surfactant in water phase, such that under suitable conditions the droplet-surface surfactant is displaced or phase inverted to the second surfactant to create desired properties followed by crosslinking to stabilize the optimal droplet, once obtained, and prevent destabilization. Given that Ren teaches that surfactant inversion can change interfacial tension and stability, a skilled person would reasonably expect that doing so could improve or promote the crosslinking reaction in existing methods.
Claims 1 and 5 are rejected under 35 U.S.C. § 103 as being unpatentable over Lee et al. (KR100306221B1; published 21 March 2002), hereinafter referred to as Lee and Lee Chol-Tae et al. (KR20160064906A; published 28 November 2014), hereinafter referred to as Lee Chol-Tae, in view of Yang et al. (Yang CH, Huang KS, Chang JY. Manufacturing monodisperse chitosan microparticles containing ampicillin using a microchannel chip. Biomed Microdevices, (2):253-9; published 09 April 2007), hereinafter referred to as Yang, and in further view of Ren and Zhang (Ren X, Zhang Y. Switching Pickering emulsion stabilized by Chitosan-SDS complexes through ion competition. Colloids and Surfaces A: Physicochemical and Engineering Aspects, volume 587, 2020, 124316; electronically published 05 December 2019), hereinafter referred to as Ren, and Azimi-Boulali et al. (Azimi-Boulali J, Madadelahi M, Madou MJ, Martinez-Chapa SO. Droplet and Particle Generation on Centrifugal Microfluidic Platforms: A Review. Micromachines (Basel),11(6):603; published 22 June 2020), hereinafter referred to as Azimi-Boulali.
Lee, Lee Chol-Tae, Yang and Ren teaches the limitations of instant claims 1 (as described above), from which instant claim 5 depends, however does not teach specific limitations of instant claim 5.
Lee teaches the using centrifugation for separation/washing of microcapsules, however Lee and Lee Chol-Tae do not teach wherein the cross-linking agent reaction is promoted by centrifugation.
Azimi-Boulali teaches centrifugal microfluidic systems and using centrifugation in droplet or bead generation and processing (Abstract). Azimi-Boulali teaches the dispenser nozzle method using centrifugal force where droplets “…travel through an air gap and enter a continuous phase to be crosslinked and collected.” and “…to use an air gap between the nozzle tip and the continuous phase, which prevents direct contact with the crosslinker solution and is faster and without cross-contamination” (page 10 and 12, section 6.2 and Figure 6), thus directly disclosing centrifugation enhanced droplet reaction with cross-linking agent.
It would have been prima facie obvious to one of ordinary skill in the art prior to the instant effective filing date to use centrifugation with microfluidic devices, as taught by Azimi-Boulali, to enhance the droplet reaction with cross-linking agent in the inventions taught by Lee and Lee Chol-Tae. One would be motivated to adopt and apply the techniques taught by Azimi-Boulali to optimize crosslinking reactions by improving crosslinker contact or reaction kinetics. Thus, instant claim 5 is obvious over the combination Lee, Lee Chol-Tae, Yang and Azimi-Boulali.
Claims 1, 6 and 7 are rejected under 35 U.S.C. § 103 as being unpatentable over Lee et al. (KR100306221B1; published 21 March 2002), hereinafter referred to as Lee and Lee Chol-Tae et al. (KR20160064906A; published 28 November 2014), hereinafter referred to as Lee Chol-Tae, in view of Yang et al. (Yang CH, Huang KS, Chang JY. Manufacturing monodisperse chitosan microparticles containing ampicillin using a microchannel chip. Biomed Microdevices, (2):253-9; published 09 April 2007), hereinafter referred to as Yang, and in further view of Ren and Zhang (Ren X, Zhang Y. Switching Pickering emulsion stabilized by Chitosan-SDS complexes through ion competition. Colloids and Surfaces A: Physicochemical and Engineering Aspects, volume 587, 2020, 124316; electronically published 05 December 2019), hereinafter referred to as Ren, and Park et al. (KR100614609B1; published 21 August 2006), hereinafter referred to as Park.
Lee, Lee Chol-Tae, Yang and Ren teaches the limitations of instant claim 1 and 6 (as described above), from which instant claim 7 depend, however does not teach specific limitations of instant claim 7.
Regarding instant claim 7, Lee teaches washing the microcapsule [droplets] with petroleum ether, separating using a centrifuge, and then drying (freeze-drying) by lyophilization (claim 6). Lee and Lee Chol-Tae do not disclose drying at room temperature.
Park Example 1 teaches “After the temperature was lowered to room temperature, sodium carbonate was added to the O / W / O emulsion solution to prepare a pH 8, and then 3 wt% calcium chloride solution was added as a crosslinking agent and stirred for 3 hours. The reaction solution was washed with distilled water and petroleum ether and dried to prepare a microcapsule.” (page 4).
It would have been prima facie obvious to one of ordinary skill in the art prior to the instant effective filing date to substitute drying at room temperature, as taught by Park, as a substitute for freeze-drying to the invention taught by Lee. Given that drying steps are routine in prior art, drying at room temp would have been an obvious choice, hence instant claim 7 can be considered obvious in view of Lee and Lee Chol-Tae and the alternative teaching of room temperature drying by Park.
New Rejections
The following new rejections are made from the previous Office Correspondence dated 22 September 2025, as the Applicant's amendment necessitated the new grounds of rejection presented below based on the amended/newly cited limitations.
Claim Rejections - 35 USC § 112(b)
The following is a quotation of 35 U.S.C. § 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. § 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which Applicant regards as his invention.
Claims 1, and 4-18 are rejected under 35 U.S.C. § 112(b) or 35 U.S.C. § 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor, regards as the invention.
Claim 1 recites, "phase-inverting the first surfactant remaining on a surface of the droplets into the second surfactant". The term “phase-inverting” is not defined with sufficient clarity. The specification does not identify whether this refers to a thermodynamic phase inversion, surfactant exchange, emulsion inversion, or another phenomenon, nor does it provide testable criteria to determine when “phase-inverting” has occurred. The description at ¶[0037] merely states that Tween 20 was used because, "the separation and precipitation reaction of the chitosan beads 130 proceeds faster than when sodium dodecyl sulfate (SDS) instead of Tween 20 is used". This describes a faster precipitation outcome but does not describe the purported "phase-inverting" step itself.
In addition, the mechanism of "phase-inverting" as applied to a surfactant, as opposed to an emulsion, unclear for the limitation of claim 1 and dependent claim 4. Surfactants are surface-active agents that adsorb at interfaces, they do not typically undergo "phase inversion" themselves. It is ambiguous whether this limitation intends to describe inversion of the emulsion type (e.g., from water-in-oil to oil-in-water) or displacement of one surfactant by another at the droplet interface. The specification at ¶[0038] describes that "the first surfactant 123 remaining on the surface of the droplets 110 is converted into the second surfactant 220 according to the above-described phase inversion," but this description does not clarify what "phase-inverting the first surfactant" means. One of ordinary skill in the art would not be able to determine with reasonable certainty when this limitation is met (see MPEP § 2173.02).
Claim 4, depending from claim 1, recites "during the producing the beads, the reaction of the droplets with the cross-linking agent is promoted by the phase-inverting." It is ambiguous whether "the phase-inverting" refers to the step of "phase-inverting the first surfactant" recited in claim 1. If so, the claim is indefinite because it is unclear how a step of phase-inverting can promote a reaction that occurs contemporaneously with or as part of the same step.
Claim 1 also recites, "generating oil emulsification, which is composed of a plurality of droplets, at an interface between the emulsion and the water phase solution." This phrase is indefinite. The term "oil emulsification" is not a standard term of art. It is unclear whether this refers to the formation of an emulsion of oil, the separation of oil as a distinct phase, or something else. Additionally, the phrase "which is composed of a plurality of droplets" modifies "oil emulsification," but "emulsification" is a process, not a composition. It is unclear whether the droplets being referred to are the chitosan droplets, new oil droplets, or something else.
Regarding the "freezing-resistant disinfectant" limitation in claim 1, the specification at ¶[0029] similarly recites that the water phase material includes a "freezing-resistant disinfectant", however, the specification provides no disclosure regarding what constitutes a "freezing-resistant disinfectant". No specific disinfectants are identified, no characteristics are described, no limitations are provided as to chemical class, composition, or freezing-resistance mechanism and no guidance is provided for selecting such a disinfectant to allow one of ordinary skill in the art to determine which disinfectants will successfully function in the claimed microfluidic encapsulation process. The Background section mentions the need for a freezing-resistant disinfectant and problems with using environmental pollutants such as antifreeze, but the specification fails to disclose any species of freezing-resistant disinfectant that would fall within the scope of the claim. While the claim recites specific ratios for purified water (1:1 with the disinfectant), acetic acid (1% v/v), and chitosan (1-3 wt%), the core freezing-resistant disinfectant component itself is completely undefined. One of ordinary skill would not understand from the specification what materials constitute a "freezing-resistant disinfectant" for purposes of the invention (see MPEP § 2163).
In addition, the phrases “predetermined flow ratio” and “predetermined diameter” are indefinite because the claims do not specify how or by whom the parameters are predetermined, nor do they require the parameters to be fixed, measurable, or reproducible at the time of infringement. The expressions “prompt a reaction” and “the reaction … is promoted by” are functional and result-oriented without reciting objective conditions, thresholds, or comparative baselines, also rendering the scope of the claims uncertain. Dependent claims 4-18 are included in the rejection of claim 1 because they do not cure the defect noted above.
Claim 6 recites, "moving oil remaining in the water phase solution to the interface by the second surfactant; and curing and precipitating the produced beads contemporaneous with the cross-linking between droplets and the cross-linking agent". The phrase "contemporaneous with the cross-linking" renders the claim indefinite because it lacks temporal precision and is unclear because it does not define whether the curing and precipitating occur complete simultaneity, requires partial overlap, or merely occurs during the same general processing step as cross-linking or whether these are separate sequential steps. The specification fails to describe whether the precipitating step occurs spontaneously, requires specific conditions, or how it is detected. The term "contemporaneous" is subjective and does not provide a clear boundary to the claim scope. The specification at ¶[0044] describes that "the produced beads are hard cured and precipitated as the cross-linking with the cross-linking agent 210 continues to proceed". However, the specification provides no description of what "curing" means in the context of chitosan beads, what parameters define when a bead is "cured" as opposed to merely cross-linked, or how one would distinguish between curing and cross-linking. Dependent claims 7, 9, 14, 15 and 17 are included in this rejection because they do not cure the defect noted above.
Claim 9 recites, "manufacturing dried beads into powders, wherein the powders can be rehydrated". The phrase "can be rehydrated" requires subjective determination without providing objective boundaries. The specification at ¶[0050] states that "the dried beads, that is, particles loaded with a freeze-resistant disinfectant, may be manufactured in the form of a powder that may be rehydrated, so that long-term stability or preservation of disinfectant performance may be ensured", however provides no description of how to achieve rehydratable powders, what conditions are required for rehydration (e.g., rehydration time, temperature, degree of reconstitution, stability upon rehydration), what degree of rehydration constitutes "can be rehydrated," or whether all powders produced by the method possess this property. One of ordinary skill would not understand from the original disclosure what is required to produce powders that "can be rehydrated" or how to determine whether a given powder meets this limitation. Dependent claim 17 is included in this rejection because they do not cure the defect noted above.
Claims 11-18 are drafted as, "An eco-friendly capsule by being manufactured by the method according to claim…". These claims are indefinite because the phrase "by being manufactured by" renders the scope of these claims unclear because one cannot determine with reasonable certainty whether a given capsule is covered by the claim merely by analyzing the capsule, without knowing the exact process by which it was made (see MPEP § 2173.05(f)). More standard product-by-process formats recite, "A product produced by the process of claim…" or "A product obtainable by the process of claim…", providing more clarity as to what is covered by the claim.
Claim 1 contains the trademark/trade name Span 80 and Tween 20. Where a trademark or trade name is used in a claim as a limitation to identify or describe a particular material or product, the claim does not comply with the requirements of 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph. See Ex parte Simpson, 218 USPQ 1020 (Bd. App. 1982). The claim scope is uncertain since the trademark or trade name cannot be used properly to identify any particular material or product. A trademark or trade name is used to identify a source of goods, and not the goods themselves. Thus, a trademark or trade name does not identify or describe the goods associated with the trademark or trade name. In the present case, the trademark/trade name is used to identify/describe particular surfactants and, accordingly, the identification/description is indefinite. Replacement of the trademarks with the chemical names of the surfactants would overcome this rejection.
Appropriate correction is required.
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, 5 and 10 are rejected under 35 U.S.C. § 103 as being unpatentable over Lee et al. (KR100306221B1; published 21 March 2002), hereinafter referred to as Lee and Lee Chol-Tae et al. (KR20160064906A; published 28 November 2014), hereinafter referred to as Lee Chol-Tae, in view of Yang et al. (Yang CH, Huang KS, Chang JY. Manufacturing monodisperse chitosan microparticles containing ampicillin using a microchannel chip. Biomed Microdevices, (2):253-9; published 09 April 2007), hereinafter referred to as Yang, and in further view of Ren and Zhang (Ren X, Zhang Y. Switching Pickering emulsion stabilized by Chitosan-SDS complexes through ion competition. Colloids and Surfaces A: Physicochemical and Engineering Aspects, volume 587, 2020, 124316; electronically published 05 December 2019), hereinafter referred to as Ren, and Azimi-Boulali et al. (Azimi-Boulali J, Madadelahi M, Madou MJ, Martinez-Chapa SO. Droplet and Particle Generation on Centrifugal Microfluidic Platforms: A Review. Micromachines (Basel),11(6):603; published 22 June 2020), hereinafter referred to as Azimi-Boulali.
Lee, Lee Chol-Tae, Yang, Ren and Azimi-Boulali teach the limitations of instant claims 1 and 5 (as described above), from which instant claim 10 depends.
Lee teaches centrifugation applied during microcapsule formation and separation, including centrifugal processing after cross-linking reactions (claim 6; page 3, ¶7-9). Lee Chol-Tae teaches continuous agitation during cross-linking to promote bead curing and precipitation, including high-speed rotational mixing for extended durations (Drawing; page 2, last paragraph).
Azimi-Boulali teaches that centrifugal force can be applied during droplet generation and cross-linking to enhance reaction kinetics, bead formation rate, and collection efficiency (Abstract; page 10, 6.2; Fig. 6), including applying defined rotational speeds for defined time periods to accelerate cross-linking reactions.
None of the cited references explicitly disclose a centrifugation condition of exactly 1200 rpm for exactly 30 minutes performed contemporaneously with cross-linking.
However, selection of a specific centrifugation speed and duration constitutes a result-effective variable, as the prior art establishes that centrifugation speed and time directly affect droplet transport, collision frequency, and cross-linking efficiency (see Azimi-Boulali, 6.1-6.2). Optimization of rotational speed and duration to achieve effective bead formation would have been a matter of routine experimentation within the ordinary skill in the art. Accordingly, claim 10 would have been prima facie obvious to one of skill in the art at the time of the invention.
Claims 1, and 4-18 are rejected under 35 U.S.C. § 103 as being unpatentable Lee et al. (KR100306221B1; published 21 March 2002), hereinafter referred to as Lee and Lee Chol-Tae et al. (KR20160064906A; published 28 November 2014), hereinafter referred to as Lee Chol-Tae, in view of Yang et al. (Yang CH, Huang KS, Chang JY. Manufacturing monodisperse chitosan microparticles containing ampicillin using a microchannel chip. Biomed Microdevices, (2):253-9; published 09 April 2007), hereinafter referred to as Yang, and in further view of Ren and Zhang (Ren X, Zhang Y. Switching Pickering emulsion stabilized by Chitosan-SDS complexes through ion competition. Colloids and Surfaces A: Physicochemical and Engineering Aspects, volume 587, 2020, 124316; electronically published 05 December 2019), hereinafter referred to as Ren, and Azimi-Boulali et al. (Azimi-Boulali J, Madadelahi M, Madou MJ, Martinez-Chapa SO. Droplet and Particle Generation on Centrifugal Microfluidic Platforms: A Review. Micromachines (Basel),11(6):603; published 22 June 2020), hereinafter referred to as Azimi-Boulali and Park et al. (KR100614609B1; published 21 August 2006), hereinafter referred to as Park.
Lee, Lee Chol-Tae, Yang, Ren, Azimi-Boulali and Park teach the limitations of instant claims 1 and 4-9 (as described above), from which instant claims 10-18 depend.
New claims 11-18 claim eco-friendly capsule manufactured by the method of claims 1, and 4-10. Lee teaches chitosan microcapsules produced by interfacial emulsion cross-linking, including capsules formed using oil/surfactant emulsions and glutaraldehyde cross-linking (claims 1-6; page 3, ¶8). Lee Chol-Tae teaches chitosan microcapsules produced using oil and surfactant systems, followed by cross-linking and curing to produce stable capsule particles (Drawing). Yang teaches that microfluidic generation of chitosan droplets followed by cross-linking produces monodisperse chitosan microparticles, which are structurally indistinguishable from bulk-produced particles except for size distribution (Abstract; pages 256-258). Ren teaches that surfactant phase inversion at droplet interfaces alters interfacial chemistry prior to stabilization, but does not change the fundamental chemical composition of the resulting chitosan beads once cross-linked (Abstract; section 3.1). Park teaches washing, curing, drying, and isolating chitosan-based microcapsules, yielding final capsule products suitable for storage and rehydration (Example 1).
The cited references do not explicitly label the final capsules as “eco-friendly,” nor do they expressly state that the capsules are “manufactured by” the specific claimed method steps of claims 4-10. However, claims 11-18 define the eco-friendly capsule solely by the process of manufacture. The patentability of such claims depends on the structure of the product, not on the process by which it is made. Where the product produced by the claimed process is the same or obvious over the product of the prior art, the claim is unpatentable even if the process differs.
The prior art teaches chitosan capsules formed by emulsion templating and glutaraldehyde cross-linking, which would inherently result in the same structural capsule regardless of whether the droplets are produced by bulk emulsification or microfluidic flow (Yang, page 258; Lee, page 3). The use of phase inversion (Ren), centrifugation (Azimi-Boulali), washing, and drying (Lee and Park) would not impart structural distinctions sufficient to distinguish the final capsule product. The prior art teaches chitosan capsules having the same structural and functional characteristics. Where the product is not shown to be structurally distinct from known capsules, patentability cannot rest on the process alone.
Further, merely describing the capsule as “eco-friendly” constitutes an intended use or subjective characterization and does not impose a structural limitation. Accordingly, claims 11-18 are obvious over the same combination of references that render the corresponding method claims obvious, because the resulting capsule products would have been inherently produced by the prior art methods.
Response to Arguments
Applicant Arguments/Remarks of the reply, filed 16 December 2025, have been fully considered.
As amended, the rejection of claim 1 under 35 U.S.C. § 103 over Lee, Lee Chol‑Tae, and Yang is maintained. The added compositional details in claim 1 (purified water, freezing-resistant disinfectant, acetic acid at 1% v/v, chitosan at 1–3 wt%, Span 80, Tween 20, glutaraldehyde) represent selection and optimization of known components routinely used in chitosan emulsion and crosslinking systems. Lee and Lee Chol-Tae teach chitosan aqueous phases, oil phases containing sorbitan surfactants, and glutaraldehyde crosslinking. Yang teaches performing these processes on a microfluidic chip with droplet size control via flow ratios. The recited concentrations and surfactant identities do not produce a structural or functional distinction sufficient to overcome obviousness, as no unexpected results are demonstrated.
The applicant argues that the examiner's reliance on Ren is an "over-generalization" because Ren teaches phase-inversion using ionic surfactants (SDS, CTAB). Since the claimed first and second surfactants (Span 80 and Tween 20) are non-ionic, the applicant contends a skilled artisan would have no reasonable expectation of success in applying Ren's teaching to achieve the claimed phase-inversion. The examiner disagrees with applicant's restrictive reading of Ren and finds that the combination of Ren with the primary references would have been obvious with a reasonable expectation of success.
While the specific examples in Ren utilize ionic surfactants, the underlying mechanism taught is not limited to ionic charge. Ren teaches the principle of competitive displacement at an oil-water interface. Ren teaches that surfactant switching at droplet interfaces alters interfacial stability, coverage, and reaction kinetics. While Ren’s exemplified systems use ionic surfactants, the principle relied upon in the rejection is not ionicity per se, but the general predictability that interfacial surfactant exchange affects emulsion stability and downstream reactions.
The abstract and conclusions clearly state the broader concept, the emulsion stability is switched by altering the composition of the interfacial layer through the introduction of a competitive surface-active agent. A person of ordinary skill in the art would recognize that this principle of competitive displacement is a fundamental interfacial phenomenon applicable to various surfactant classes, including non-ionic surfactants. The core teaching is that introducing a second surfactant (Tween 20 in the claimed invention) can displace a first surfactant (Span 80) from the droplet interface, leading to phase inversion or changes in stability.
The primary references, Lee and Lee Chol-Tae, specifically teach the use of non-ionic surfactants. Lee teaches sorbitan monooleate (Span 80). Lee Chol-Tae teaches the use of Span 80 in the oil phase. A person of ordinary skill in the art seeking to control the interfacial properties and cross-linking reaction of the chitosan droplets taught by Lee and Lee Chol-Tae would be motivated to apply the competitive displacement principle of Ren. Since the existing system already utilizes non-ionic surfactants (e.g., Span 80), it would be a routine design choice to select a compatible non-ionic surfactant (like Tween 20) for the aqueous phase to perform the displacement, as claimed. There is no teaching in Ren that its principle is only operable with ionic surfactants. The predictable result of introducing a different surfactant with a different HLB value into the continuous phase is an alteration of the interfacial tension and surfactant packing, which can lead to displacement or phase inversion. Therefore, a person of ordinary skill in the art would have had a reasonable expectation of successfully using non-ionic surfactants in this context.
A person of ordinary skill in the art would reasonably expect that introducing a second surfactant with different HLB and affinity (e.g., Tween 20) into the aqueous crosslinking phase would displace or reorganize a first surfactant (e.g., Span 80) at the droplet interface, and such displacement would predictably alter permeability and facilitate crosslinking. As noted in the previous Office Action, the claimed step of "phase-inverting the first surfactant... into the second surfactant" is an inherent result of the claimed process, providing droplets stabilized by Span 80 and then contacting them with a solution containing Tween 20. The very act of introducing a second, different surfactant into the continuous phase will alter the interfacial composition. Whether this is termed "phase inversion" or "surfactant displacement," it is an inevitable and predictable physicochemical outcome of the combination taught by Lee and Lee Chol-Tae (using Span 80) and Ren (introducing a competitive surfactant). As such, reciting this inherent result does not render the claim patentable.
Obviousness does not require certainty of success, only a reasonable expectation of success. The Examiner does not rely on Ren as teaching a specific non-ionic pair, but rather as providing motivation and predictability for surfactant-mediated interfacial modification. This is consistent with MPEP § 2143. Accordingly, the amended recitation of “phase-inverting the first surfactant … into the second surfactant” does not patentably distinguish claim 1. Since the argument regarding phase-inversion does not distinguish the claims, and because the other limitations of independent claim 1 are taught by the combination of Lee, Lee Chol-Tae, and Yang as previously detailed, the obviousness rejection is maintained.
The rejections of claims 4 and 6 remain maintained. Lee Chol-Tae teaches that crosslinking kinetics affect capsule formation quality. Ren teaches that surfactant switching affects stability and interfacial behavior. It would have been obvious to use surfactant-mediated interfacial changes to promote crosslinking efficiency or oil migration, as claimed. The applicant’s arguments regarding ionicity do not overcome the motivation to combine these teachings.
The rejection of claim 5 under §103 over Lee, Lee Chol-Tae, Yang, and Azimi‑Boulali is maintained, and extended to newly added claim 10. Azimi-Boulali expressly teaches centrifugal microfluidic techniques that enhance droplet formation and crosslinking reactions. Specifying centrifugation parameters (1200 rpm, 30 minutes) in claim 10 constitutes routine optimization of process conditions, which is prima facie obvious absent evidence of unexpected results.
The rejection of claim 7 remains maintained over Lee in view of Park. Substituting room-temperature drying for freeze-drying is a well-known alternative and represents an obvious process variation.
The new claims 10-18 are rendered obvious by the same combination of references, as they merely recite further limitations that are either obvious or taught by the secondary references.
Thus, in summary, the applicant’s arguments regarding non-ionic surfactant phase inversion are not persuasive. The amendments to claim 1 do not overcome the prior art combinations previously applied. All pending claims 1 and 4-18 remain rejected under 35 U.S.C. § 103 for the reasons stated above. No evidence of unexpected results or criticality has been provided.
Conclusion
No claims are allowed.
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 nonprovisional extension fee (87 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.
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/RL Scotland/
Examiner, Art Unit 1615
/Robert A Wax/Supervisory Patent Examiner, Art Unit 1615