DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Election/Restrictions and Status of Claims
Applicant’s election of Group I in the reply filed on 11/03/2025 is acknowledged. Because applicant did not distinctly and specifically point out the supposed errors in the restriction requirement, the election has been treated as an election without traverse (MPEP § 818.01(a)).
Applicant was further contacted via telephone since the original restriction requirement contained an error in that claims 15-18 were grouped in the invention of Group I (i.e., composition) rather than Group II (i.e., process). During a telephone conversation with Shenbin Wu on 12/10/2025 a provisional election was made without traverse to prosecute the invention of new Group I, claims 1-5 and 10-14. Affirmation of this election must be made by applicant in replying to this Office action. Claims 6-9 and 15-18 are withdrawn from further consideration by the examiner, 37 CFR 1.142(b), as being drawn to a non-elected invention. Given Applicant’s election of Group I (i.e., the microcapsule itself), claims 10-14 which contain unconventional US claim language, are treated herein as being drawn to the microcapsule product in accordance with Group I.
Claims 1-5 and 10-14 are examined on the merits herein.
Priority
The instant application filed 11/08/2023, claims foreign priority to CN202311160919.2, filed 09/08/2023.
Claim Objections
Claim 3 is objected to because of the following informalities: “Polydimethylsiloxane” is unnecessarily capitalized. Please remove capitalization.
Claim Rejections - 35 USC § 101
35 U.S.C. 101 reads as follows:
Whoever invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof, may obtain a patent therefor, subject to the conditions and requirements of this title.
1. Claims 10-14 are rejected under 35 U.S.C. 101 because the claimed invention is directed to non-statutory subject matter. The claims do not fall within at least one of the four categories of patent eligible subject matter because they recite a “use” rather than a process, machine, manufacture, or composition of matter. Given that the claims fail to define any positively recited, active steps that would properly define a process claim within the meaning of 35 U.S.C. §101, the use claims are being interpreted in line with the election of Group I which is to the microcapsule itself (i.e., a composition).
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 the applicant regards as his invention.
Claims 1, 5, and 10-14 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 (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
It is unclear what the term “active substance” refers to in claim 1. For example, is it a pharmaceutical active, cosmetic active, agrochemical active, surface active, a dye for visualization, a flavor agent, etc.? Furthermore, claims 10-14 define the use of the composition in various fields without defining the active agent. It is unclear if a different active is used in different applications or if one active is applicable to the fields of cosmetics, pharmaceuticals, and foods at the same time.
Claim 1 recites several percentages without reciting the basis for such amounts. For example, are they based on the weight of the core, the shell, or the microcapsule as a whole? As such, the claim is indefinite. For the sake of compact prosecution wt% will be interpreted as being based on the total weight of the phase in which the component is contained.
The term “residual” in claim 1 is a relative term which renders the claim indefinite. The term “residual” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. The Examiner has no means of determining what qualifies as a “residual” amount of water, especially given that the microcapsules are prepared by using an aqueous solution as the core phase as defined in embodiments 1-3 of the instant specification. Step 6 of the preparation defines incubating the microcapsules at elevated temperatures for 2.5 to 2.5 hours, however, it is unclear if the water in the aqueous core is removed during this step, and if so, to what extent.
Claim 1 and 2 recite the abbreviations “PVA” and “PEG” without defining the full name of the compound which is being referred to, thereby rendering the claims indefinite. Please write out the full compound name in addition to or in place of the abbreviation.
Claim 5 recites wherein the microcapsule has an inflated degree (alpha) of more than 1.63. The instant specification defines “inflated degree” as a volume ratio of an inflated microcapsule to a microcapsule before inflation (p. 4 of instant specification). Inflating treatment, as defined by the instant specification, comprises transferring the microcapsules to an aqueous solution, and adjusting an osmotic pressure of the aqueous solution until the microcapsules have an inflated degree α more than 1.63. When the osmotic pressure of the aqueous solution is much less than the osmotic pressure of the core phase of the microcapsules, and internal flow is formed in water (p. 6 of instant spec.). Thus, it is unclear how the microcapsules can contain a residual amount of water and also be inflated with water.
Claims 10-14 recite a “use”, making it unclear if the claims are drawn to a composition or a method of using said composition. As set forth above, and for the purpose of compact prosecution, claims 10-14 are interpreted as being directed to a composition since the claims fail to define any positively recited, active steps that would properly define a process claim within the meaning of 35 U.S.C. §101. The recited limitations directed to the “use” of the microcapsule will be interpreted as an intended use of the composition per se.
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.
1. Claims 1, 3-5, 10, and 12-14 are rejected under 35 U.S.C. 103 as being unpatentable over Guo, J., et al. (2020). Generation of Ultra-Thin-Shell Microcapsules Using Osmolarity-Controlled Swelling Method. Micromachines, 11(4), 444 (PTO-892), hereinafter Guo.
Guo teaches an osmolarity-controlled swelling method for the mass production of monodisperse microcapsules with ultra-thin shells via water-in-oil-in-water (W/O/W) double-emulsion drops templating with a capillary microfluidic device (abstract).
Regarding claim 1: The inner phase, which corresponds to the core phase, comprises an aqueous solution of PVA. KCl is added into the inner phase and suspending medium to adjust the osmotic pressure between the inner and outer phase of the shell, therefore reading on a density enhancer. Methylene blue is also added to the inner core as a dye for better visualization, therefore reading on an active substance (p. 3, section 2.1). The middle oil phase, which corresponds to the shell phase, comprises a mixture of PDMS (i.e., an elastomer precursor) and silicone oil, to which a curing agent is added for solidifying the double-emulsion drops into microcapsules (p. 3, section 2.1).
Regarding claim 3, the elastomer precursor is polydimethylsiloxane as discussed above.
Regarding claim 4, the curing agent is added for solidifying the double-emulsion drops into microcapsules (p. 3, section 2.1). The PDMS shell is cured at 37 °C for 24 h to obtain the microcapsules (p. 7, section 3.3), meaning that the curing agent is capable of curing PDMS (i.e., the elastomer precursor).
The teachings of Guo differ from that of the instantly claimed invention in that Guo does not explicitly teach the various ratios and amounts of each component in claim 1 nor does Guo explicitly teach an inflated degree of more than 1.63 as defined in claim 5.
Regarding the volume ratio of the core phase to the shell phase as defined in claim 1: Guo teaches that the core volume of the microcapsules can be controlled by changing the salt concentration of the suspending medium and therefore inducing osmolarity-controlled swelling (p. 5, Section 3.1). See diagram below:
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Likewise, when the ultra-thin-shell microcapsules are placed in a suspending medium with KCl concentration of 0.5 mol/L, the inner aqueous phase diffuses out from the PDMS microcapsules, resulting in a volume shrinkage of the microcapsules (p. 7, Section 3.3, para. 2). Thus, it would have been obvious to one of ordinary skill in the art to selectively adjust the volume ratio of the core phase to the shell phase depending on the desired structure of the final microcapsule. As such, one of ordinary skill in the art would have arrived at the instantly claimed ratio through no more than routine experimentation by adjusting KCl concentration in the suspending medium as taught by Guo. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Regarding the “residual amount” of water in the core phase as defined in claim 1: For the same reasoning discussed above, it would have been obvious and within the skills of an ordinary artisan to adjust the amount of water in the core phase by adjusting the osmotic pressure between the suspending medium and the core phase as taught by Guo. Thus, one of ordinary skill in the art would have arrived at the instantly claimed invention through no more than routine experimentation regardless of the amount of water needed to be considered “residual”.
Regarding the amount of the other agents in the core phase as defined in claim 1: PVA is provided in the inner phase at 1 wt% (p. 3, 2.1) and KCl at 0.25 mol/L (p. 6, para. 1). The amount of methylene blue is not explicitly taught but it is necessarily present at some amount that provides a visual effect. While such amounts do not fall within the instantly claimed ranges of claim 1, it is well within the abilities of an ordinary artisan to optimize the amount of each component in the core phase depending on the desired properties and structure of the final product. As such, one of ordinary skill in the art would have arrived at the instantly claimed ranges of PVA, KCl (i.e., density enhancer), and methylene blue (i.e., active substance) through no more than routine experimentation. Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Regarding the mass ratio of each agent in the shell phase as defined in claim 1: PDMS (i.e., elastomer precursor) and silicone oil are provided at a volume ratio of 3:1, into which the curing agent is added at 10 wt% (p. 3, section 2.1). While such amounts do not directly align with the instantly claimed ratio, which is a mass ratio between all three components, it is well within the abilities of an ordinary artisan to optimize the amount of each component in the shell phase depending on the desired properties (i.e., shell hardness) of the final product. As such, one of ordinary skill in the art would have arrived at the instantly claimed ratio of elastomer to curing agent to silicone oil through no more than routine experimentation. Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Regarding claim 5: The instant specification defines “inflated degree” as a volume ratio of an inflated microcapsule to a microcapsule before inflation (p. 4 of instant specification). Guo teaches that the core volume of the microcapsules can be modulated via the KCl concentration in the suspending medium which can induce an osmolarity-controlled swelling behavior (p. 5, Section 3.1). See the figure below:
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As such, it would have been obvious to one of ordinary skill in the art to selectively adjust the degree of swelling (i.e., inflated degree) depending on the desired structure of the final microcapsule. As such, one of ordinary skill in the art would have arrived at the instantly claimed inflated degree (alpha) through no more than routine experimentation by simply adjusting KCl concentration in the suspending medium as taught by Guo. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Regarding claims 10 and 12-14: The microcapsules of claims 1 and 3-5 are rendered obvious above, thereby rendering the microcapsules of claims 10 and 12-14 obvious. Given that the microcapsules of the prior art meet all of the structural limitations as defined in claims 1 and 3-5, the microcapsules of Guo are inherently capable of performing the claimed intended use. Furthermore, Guo teaches that microcapsules can serve as model systems in various applications such as drug delivery (i.e., pharmaceuticals) and food (p. 1, intro., para. 1).
Claims 1-5 and 10-14 are rejected under 35 U.S.C. 103 as being unpatentable over Guo as applied to claims 1, 3-5, 10, and 12-14 above, and further in view of Feng C, et al. (2022) Simple One-Step and Rapid Patterning of PDMS Microfluidic Device Wettability for PDMS Shell Production. Front. Bioeng. Biotechnol. 10:891213 (PTO-892), hereinafter Feng.
The teachings of Guo are discussed above.
The teachings of Guo differ from that of the instant invention in that Guo does not teach wherein the density enhancer comprises one of those selected from claim 2.
Feng teaches double emulsion (DE) droplets with controlled size and internal structure (abstract). Solidified PDMS microcapsules were generated by preparing w/o/w DE droplets. The inner phase (i.e., core) comprises PBS, 5% w/v glycerol and 1% w/v PVA. The middle phase (i.e., shell) comprises a mixture of PDMS and silicone oil and a reticulating agent which is used to solidify the PDMS layer (i.e., curing agent) (p. 3, Double emulsion Droplets Generation, para. 2). The glycerol of Feng reads on the density enhancer of claim 2 while 5% reads on the amount of density enhancer defined in claim 1.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to add the glycerol of Feng into the core phase of Guo, specifically at a concentration of 5 wt%, since 5% glycerol in an aqueous PVA core phase is known and routine in the art as taught by Feng. Generally, the combination of prior art elements according to known methods to yield predictable results is considered prima facie obvious. In the instant case, both Guo and Feng teach solidified PDMS microcapsules formed from w/o/w double-emulsion droplets. The combination of Guo and Feng which contains glycerol in the core, renders the density enhancer of claims 1 and 2 obvious.
One of ordinary skill in the art would have had a reasonable expectation of success in adding 5% glycerol to the core phase of Guo since Feng teaches 5% glycerol to be compatible in an aqueous PVA core in microcapsules further comprising a PDMS, silicone oil, and curing agent shell.
Regarding claim 11: The microcapsule of claim 2 is rendered obvious above, thereby rendering the microcapsule of claim 11 obvious as well. Given that the microcapsules of the prior art meet all of the structural limitations as defined in claims 1-2, the microcapsules of Guo are inherently capable of performing the claimed intended use. Furthermore, Guo teaches that microcapsules can serve as model systems in various applications such as drug delivery (i.e., pharmaceuticals) and food (p. 1, intro., para. 1). And Feng teaches that water-in-oil (w/o) droplets generated by microfluidic devices have been widely applied in pharmaceuticals, foods, and cosmetics (p. 1, intro).
Conclusion
No claims allowed.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SUSANNAH S ARMSTRONG whose telephone number is (571)272-0112. The examiner can normally be reached Mon-Fri 7:30-5 (Flex).
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/SUSANNAH S ARMSTRONG/Examiner, Art Unit 1616
/Mina Haghighatian/Primary Examiner, Art Unit 1616