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
To summarize the current election, the applicant elected group II and the species where the polymer is a polyamide and the metal salt precursor is silver nitrate, with traverse.
The requirement is still deemed proper and is therefore made FINAL.
Claims 4-5, 8, and 11-16 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention and species, there being no allowable generic or linking claim.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1-3, 6-7, and 9-10 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Claim 1 recites a method whose required equipment configurations were not disclosed. The disclosure only details configurations of equipment that combine a polymer dissolved in a solvent and a metal salt precursor dissolved in a solvent that is miscible with the polymer solution solvent (as recited in steps (a) and (b) of claim 1) via two syringes into a three way connector that is followed by a connector which dispenses the result into a coiled flow reactor (see figure 1b and specification page 5 lines 12-28). In figure 1b, the three-way connector component 7 enters the reactor component 4 which is inside microwave heating source 3, while an unlabeled length of connector extends from the three-way connector to the reactor and is depicted as being mostly outside the microwave heating source and thereby subject to the ambient temperature conditions.
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Thus the disclosed design has the solution from steps (a) and (b) of claim 1 combined in the space between the three-way connector 7 and the reactor 4, yet claim 1 appears to preclude this occurrence because it states that solutions are only combined in the three-way connector. It is not clear how the disclosed configurations provide basis for the configuration now claimed
In addition, the design of figure 1b is stated to “ensure the NPs were only produced in the reactor under microwave flow conditions” (see specification page 2 lines 28-29). The heating zone is not shown or detailed to abut the three way connector nor is a three way connector/connection described as the inlet into the reactor. Several of the disclosed components of the polymer solution and metal salt precursor solution are also disclosed to react at room temperature when combined. For example. dimethyl formamide is noted instantly to be able to act as a reducing agent at ambient conditions on silver nitrate and generate silver nanoparticle (see page 14 lines 16-23). This solvent is claimed as the polymer solvent and is also exemplified in this role in a reaction conducted with silver nitrate dissolved in dimethyl sulfoxide (see instant claim 7). While the metal salt precursor solution is generated with a non-reducing solvent in the example, practice of the claimed method requires homogeneous mixing prior to entry into the reactor. Once mixing occurs, reaction of the metal precursor can occur with a solvent or any other component that can act as a reducing agent at ambient conditions. Another example employs a reducing agent initially solubilized in a reducing solvent separate from the silver nitrate metal precursor solution, but they too also would combine prior to the reactor and are able to react (see specification page 14 lines 3-14). In addition, most of the short listing of disclosed solvents do not dissolve the elected polymer (see specification page 11 lines 23-29 and Dimethyl sulfoxide solubility data 2007 table 3). One example suggests a combination that may not be reactive between the three-way connector and coiled reactor of figure 1b, namely the combination of N-methyl-2-pyrrolidone (NMP) with silver nitrate and polyamide. Beyond the example of NMP and nylono-6, it is not clear which polymers, solvents, and production equipment configurations combine to operate as instantly claimed. Most of the examples would not function as instantly claimed in the production equipment configuration that is disclosed. There is no generalized discussion to fill the void to delineate the combination of reactants, solvents, and equipment that extend the singular disclosed embodiment such that others with the claimed operation/function could be elucidated. As a result the artisan of ordinary skill would not have deemed the applicant to be in possession of the invention as claimed at the time of filing.
This is a new matter rejection.
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 1-3, 6-7, and 9-10 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.
Claim 1 still appears to recite a conflicting/contradictory scope. In light of the amendment to claim 1, the claims require a homogeneous mixture of the solutions from step (a) and step (b) after mixing in a three-way connector, and before reaching the coiled flow reactor. The amendment now recites that, at the same time, the solutions from step (a) and step (b) are only combined with each other in the three way connector. This seems to imply that there is no permitted flow path/length after the three-way connector to complete the formation of the homogeneous mixture. The scope of three-way connectors that are able to produce instantaneous homogeneity is not detailed.
Claims that are included in the rejection but are not elaborated upon are also indefinite because they depend from an indefinite claim and do not add clarity.
For the sake of application of prior art, whatever degree of mixture of two liquids exiting a three-way connector will be deemed sufficient to meet the instant claim limitation of “homogeneous”. Clarification is still required.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-3, 6-7, and 9-10 are rejected under 35 U.S.C. 103 as being unpatentable over Manno et al. (previously cited) in view of Sasmito et al. (Industrial and Engineering Chemistry Research 2012 51:1970–1980), Karandikar et al. (US PGPub No. 2007/0003603), Shi et al. (previously cited), Deadman et al. (previously cited).
Manno et al. teach preparing silver nanoparticles in a helical (coiled) microfluidic reactor by applying constant microwave heating to the reactor (see abstract, page 12704 second column last partial paragraph-12705 first column fist partial paragraph, and figure 1; instant claim 1). A solution of polyvinyl pyrrolidone, as a polymer stabilizer, dissolved in ethylene glycol as a reducing agent is placed in one syringe and a solution of silver nitrate in water (non-reducing aqueous solvent) is placed in second syringe (see page 12703 second column last partial paragpah-12704 second column first partial paragraph and figure 1; instant claim 1). A syringe pump feeds the two solutions into a three way connector which then feeds into the helical (coiled) flow reactor (see page 12703 second column last partial paragraph-12704 second column first partial paragraph and figure 1; instant claim 1). A single concentration for each solution is employed and they are fed at the same flow rate that is varied to assess the impact on the final product (see page 12703 second column last partial paragpah-12704 second column first partial paragraph; instant claim 1). Manno et al. teach that the microwave heated reactor yielded a narrower size distribution of silver nanoparticles as compared to conventional heating and that the particle size decreased with increasing flowrate (see figure 5 and table 2). In addition, the highest tested flowrate produced a set of particles that included particles sized less than 5 nm (see figure 5). The concentration of polymeric stabilizer is 240 mg/ml and is combined at an equal flowrate with a 15.7 mg/ml silver nitrate solution (see figure 1). An example detailed in the instant specification employed a 4 mg/ml solution of polyamide polymeric stabilizer and a 0.001 M (0.17 mg/ml) solution of silver nitrate to prepare their nanocomposite composed of a polymer matrix in which nanoparticles are distributed (see page 14 lines 1-14). Since the concentration of polymer in the product of Manno et al. exceeds that employed in the instant example, the product has sufficient polymer to form a matrix in which the formed silver nanoparticles are homogeneously distributed and qualifies as an instant “nanocomposite”. They note the possibility of a small occurrence of reaction at room temperature in the short distance between the three-way connector and the heating zone which they neglect as having little contribution to particle formation due to its small volume and short length (see page 12707 second column last partial paragraph). Manno et al. do not teach a polyamide as a stabilizing polymer, an instantly claimed solvent, or controlled pressure via a pressure regulator and pressurized gas.
Sasmito et al. teach alternative designs for three-way connectors/junctions (see abstract). They detail a design where a T-junction immediately exits into a coiled “reactor” (see figure 1d).
Karandikar et al. teach the production of silver nanoparticles from a combination of a silver salt, a reducing agent, a stabilizing agent, and a solvent (see abstract). Here stabilizing agents are envisioned as a polymer or surfactant (see abstract). They teach contemplated varieties of stabilizing agents to include polyamides as well as homopolymers of monomers that include 2-vinyl pyrrolidone (polyvinyl pyrrolidone) (see paragraph 69). An example employs microwave heat and polyvinyl pyrrolidone as a polymer stabilizer that is dissolved along with the other components in a solvent (see paragraph 270).
Shi et al. teach of the production of antimicrobial polymer nanocomposite that is converted into nanofibers for biomedical materials (see abstract and page 10330). They detail combining silver nitrate with a solution of nylon-6 as a stabilizer in the reducing solvent formic acid with (see abstract page 10331 first column first and third full paragraphs; instant claims 2-3, 7, and 9-10). The product is electrospun into nano fibers (polymer nanocomposite) and the nanoparticles are present uniformly in the nanofibers (see page 10331 first column fourth full paragraph, page 10332 second column last paragraph and figures 2-4).
Deadman et al. teach of the benefit of employing a pressurized collection vessel for chemical reactions in microfluidic reactors that produce a slurry, in order to reduce blockages in the reactor that commonly occur in tubular flow reactors (see page 259). They detail a collector where the outlet of the reactor feeds through a junction of a pressurized gas feed and pressure regulator, and then empties into the collection chamber (see figure 1; instant claim 1).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to prepare a silver nanoparticle-polymer nanocomposite via a modified procedure of Manno et al., where the apparatus is modified to eliminate the length between the three-way connector and the coiled flow reactor such that the three-way connector is immediately followed by the microwave exposed coiled flow reactor. This modification would have been obvious because Manno et al. find it prudent to ignore any small contribution the region prior to the microwave zone makes to reaction nucleation, which implies a preference that the post-mixing/pre-microwave region is not present. Toward this end Sasmito et al. teach a three-way connector terminating at a coiled reactor, indicating that such a serial arrangement of components was already appreciated to be useful in the art. It additionally would have been obvious to perform the nanoparticle reaction with other known combinations of stabilizing polymer dissolved in a reducing solvent, namely the formic acid and nylon-6 (polyamide) taught by Shi et al. These modification are obvious as the simple substitution of one known known element for another in order to yield a predictable outcome. Karandikar et al. further support the obviousness of the substitution via their teaching of polyamides and polyvinylpyrrolidone as alternative stabilizers as well as the utility of a general reducing agent for such reactions. It also would have been obvious to employ a pressurized collection vessel configuration of Deadman et al. since the reaction produces a slurry in a microfluidic reactor as the application of the same technique to a similar product in order to yield the same improvement. The particle size is a result-effective variable based upon solution flowrate; therefore, it would have been obvious to optimize as a matter of routine experimentation. Therefore claims 1-3, 6-7, and 9-10 are obvious over Manno et al. in view of Sasmito et al., Karandikar et al., Shi et al., and Deadman et al.
Response to Arguments
Applicant's arguments filed July 7, 2026 have been fully considered. In light of the amendment to the claims, the rejections under 35 USC 112 and objections are hereby withdrawn. The rejection under 35 USC 103 is modified in light of the amendment and new grounds of rejection are detailed to address the new claim scope. The arguments still pertinent to the rejection are addressed below.
The applicant argues that Manno et al. teach away from sequestering the reaction of the metal precursor to the reactor. While Manno et al. note the possibility of the occurrence of a small degree of reaction before their heated reactor is entered, they do not teach away from limiting the reaction to occur in the reactor. Their focus is on microwave assisted reaction and they ultimately view the pre-reactor reaction as negligible or, in other words, preferably not present (see page 12707 second column last partial paragraph). Thus their discussion supports the minimization or eradication of pre-reactor reaction, given the benefits they tout for the control of the product via the microwave assisted process (see page 12708 second column last partial parapah-12709 second column).
The applicant argues that the heat assisted reductive process in Manno et al. would not predictably occur if other reducing agents were present. To the contrary, prior art already recognized the continued utility of formic acid as a reducing agent in silver nanoparticle preparation at elevated temperatures (e.g., about 80⁰C) (see Yoon et al. Scientific Reports 2015 5(14177):1-10, page 9 third full paragraph).
The applicant also argues that the process of Manno et al. does not form a slurry, but instead makes a colloid. Thus the collection apparatus configuration of Deadman et al. would not be applicable. In contrast to the applicant’s argument, a colloid can be considered a slurry (see Kumar et al. US Patent No. 6,726,990 column 10 lines 20-23). Both are terms that describe a collection of particles dispersed in a liquid medium. Thus one would expect common issues when either is produced in tubular reactors.
In response to applicant's argument that the examiner's conclusion of obviousness is based upon improper hindsight reasoning, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. But so long as it takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper. See In re McLaughlin, 443 F.2d 1392, 170 USPQ 209 (CCPA 1971).
The applicant also argues that the modification set forth in the rejection destroys the function of Manno et al. because the room temperature reaction of Shi et al. is run for 24 hours. This argument is unpersuasive because heat is well known to increase the pace of chemical reactions. There is no evidence based reason of record to expect the increased rate of reaction that heat addition provides to the reductive process of Manno et al. to no longer occur when another known reductant is employed.
The applicant also argue that the pressurized collection of Deadman et al. would not apply to the microfluidic device of Manno because the reactor of Deadman et al. is much larger. The test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference; nor is it that the claimed invention must be expressly suggested in any one or all of the references. Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981). The concept of the pressurized collection system of Deadman et al., adjusted for scale, would reasonably apply to the dispersion/slurry/colloid generating system of Manno et al. (see page 262 second column). Its application to the end of the system would not require the omission of a quenching step at the end of the process of Manno et al., contrary the applicant argument. Further, prior art had already recognized more deliberate means of quenching at the end of processes like that of Manno et al. by incorporating a water cooled quenching stage (see Manno et al. Chemistry of Materials 2020 32:2874−2883, abstract and figure 1). Thus the modification set forth in the rejection would have been well within the skills of the artisan of ordinary skill.
The applicant additionally argues that the modifications set forth in the rejection change the principle of operation of Manno et al. To the contrary, the principle of operation of Manno et al. is the preparation of a monodisperse small sized population of silver nanoparticles stabilized by a polymer and generated via a microwave assisted reductive reaction with silver nitrate as the metal precursor. While their focus is on a category of this process that employs polyvinylpyrrolidone as a stabilizer, they acknowledge the utility of others in the field (see page 12602 second column last partial paragaph-page12704 first column).
Conclusion
No claim is 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 (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 CARALYNNE E HELM whose telephone number is (571)270-3506. The examiner can normally be reached Mon-Fri 9-5.
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/CARALYNNE E HELM/Examiner, Art Unit 1615
/MELISSA S MERCIER/Primary Examiner, Art Unit 1615
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