DETAILED ACTION
This detailed action is in response to the amendments and arguments filed on 07/11/2025, and any subsequent filings.
Notations “C_”, “L_” and “Pr_” are used to mean “column_”, “line_” and “paragraph_”.
Claim 12 is canceled. Claims 1-7, 10-11, 13-14, 17, 19-21, and 35-38 are pending.
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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 07/11/2025 has been entered.
Response to Arguments
Claim Rejections - 35 USC § 103
In response to applicant's argument that the present application does not involve an intention of performing froth flotation, a recitation of the intended use of the claimed invention must result in a structural difference between the claimed invention and the prior art in order to patentably distinguish the claimed invention from the prior art. If the prior art structure is capable of performing the intended use, then it meets the claim.
In response to applicant's argument that the references fail to show certain features of the invention, it is noted that the features upon which applicant relies (i.e., no intention of performing froth flotation) are not recited in the rejected claim(s). Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993).
Response to 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.
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, 7, 14 are rejected under 35 U.S.C. 103 as being unpatentable over Publication Quantitative Separation of Graphene Oxide Nanoribbon by Froth Flotation (‘Meisam’, Journal of Dispersion Science and Technology, 36:7, 924-931) in view of Publication Effect of nanobubbles on the flotation of different sizes of coal particle (‘Fan’, Minerals & Metallurgical Processing, 2013, Vol. 30, No. 3, pp. 157-161) and in further view of U.S. Publication US20190178773A1 (‘Tsai’).
The Applicant’s claims are directed towards a method.
Regarding Claims 1, 7, 14, Meisam teaches a method for redistributing a flake material (abstract), in particular a two-dimensional nano flake material, into at least two flake fractions (Fig. 2), the method comprising:
providing a dispersion of the flake material in a liquid, arranging the dispersion in a container (section 2.4. Froth Flotation Experiment),
percolating gas bubbles upwardly through the dispersion , for a time sufficient to allow the flake material to redistribute itself in the liquid (section 2.4. Froth Flotation Experiment), and
extracting at least one of the flake fractions from a limited vertical level of the container (Fig. 2, section 2.4. Froth Flotation Experiment).
Meisam does not teach that the at least two flake fractions are at least two flake size fractions, each of which having smaller flake size variance than the flake material, the flake material not being atomized in the liquid, larger sized flakes higher up in the liquid and smaller sized flakes lower down in the liquid, and the gas bubbles presenting an average diameter of 200 nm - 1000 nm on release to the dispersion.
Fan also relates to a method for redistributing a flake material (abstract), in particular a two-dimensional nano flake material, into at least two flake size fractions (Figs. 1 and 3), each of which having smaller flake size variance than the flake material (Fig. 3), the method comprising:
percolating gas bubbles upwardly through the dispersion (section Experimental), for a time sufficient to allow the flake material to redistribute itself in the liquid with larger sized flakes higher up in the liquid and smaller sized flakes lower down in the liquid (Fig. 3, pg. 159, larger particle sizes in recovered froth and smaller particle sizes in tailings), and
the gas bubbles presenting an average diameter of 200 nm - 1000 nm on release to the dispersion (abstract).
Tsai also relates to a flake material, in particular a two-dimensional nano flake material (abstract), wherein the flake material is not atomized in the liquid ([0019-0022]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the at least two flake fractions of Meisam can be at least two flake size fractions, each of which having smaller flake size variance than the flake material, wherein larger sized flakes are higher up in the liquid and smaller sized flakes are lower down in the liquid, wherein the gas bubbles present an average diameter of 200 nm – 1000 nm on release to the dispersion, as demonstrated by Fan, because both Meisam and Fan involve percolating gas bubbles upwardly through a dispersion (Meisam, section 2.4. Froth Flotation Experiment and Fan, section Experimental). It would have been obvious that the flake material of Meisam and Fan is not atomized in the liquid because Tsai teaches a separate atomization step to atomize graphene oxides in solution (Tsai, [0022]), thus the step of providing a dispersion of the flake material in a liquid does not include atomizing the flake material (Tsai, [0019]). Note that both Meisam and Tsai involve graphene oxide flake materials (Meisam, abstract and Tsai, abstract).
Additional Disclosures Included:
Claim 7: the flake material consists essentially of graphene and/or graphene oxide (Meisam, abstract).
Claim 10: the liquid comprises water (Meisam, section 2.1. Materials).
Claim 14: the gas bubbles are supplied in an amount of 5 to 25 ml/min/cm2 of cross-sectional area of the container (see Non-Final Rejection, dated 06/10/2024, for sample calculation).
Claims 2-4, 13 and 37 are rejected under 35 U.S.C. 103 as being unpatentable over Publication Quantitative Separation of Graphene Oxide Nanoribbon by Froth Flotation (‘Meisam’, Journal of Dispersion Science and Technology, 36:7, 924-931), Publication Effect of nanobubbles on the flotation of different sizes of coal particle (‘Fan’, Minerals & Metallurgical Processing, 2013, Vol. 30, No. 3, pp. 157-161) and U.S. Publication US20190178773A1 (‘Tsai’) as applied to claims 1 and 20 above, and further in view of U.S. Publication US20100028681A1 (‘Dai’).
The Applicant’s claims are directed towards a method.
Regarding Claims 2-4 and 13, the combination of Meisam, Fan and Tsai teaches the method of Claim 1, except that the flake material presents an average thickness of 0.1 to 2 nm, an average flake size, as measured by flake surface area, in the range of 25 to 2500 nm2 and a flake lateral dimension to thickness ratio of about 50 – 500.
Dai also relates to a flake material, in particular a two-dimensional nano flake material (abstract), wherein the flake material presents an average thickness of 0.1 to 2 nm (Fig. 13B, [0088]), an average flake size, as measured by flake surface area, in the range of 25 to 2500 nm2 (Fig. 13A, length between 0 and 600 nm, and [0041], width not more than about 100 nm) and a flake lateral dimension to thickness ratio of about 50 – 500 (Fig. 13A, length between 0 and 600 nm, and [0041], width as low as 10 nm and not more than about 100 nm).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the flake material of Meisam, Fan and Tsai can present an average thickness of 0.1 to 2 nm, an average flake size, as measured by flake surface area, in the range of 25 to 2500 nm2, and a flake lateral dimension to thickness ratio of about 50 – 500, as demonstrated by Dai, because Meisam and Dai are both concerned with nanoribbons (Meisam, abstract and Dai, [0019] and [0041]).
Additional Disclosures Included:
Claim 13: a flake size to gas bubble size ratio is 0.00005 to 0.025. It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the flake size to gas bubble size ratio of Meisam, Fan and Tsai can be 0.00005 to 0.025 because both Meisam and Dai are concerned with nanoribbons (Meisam, abstract and Dai, [0019] and [0041]) and Meisam and Fan are both concerned with froth flotation (Meisam, abstract and Fan, abstract). Sample calculation below:
Flake size: Dai, Fig. 13A, length between 0 and 600 nm, [0041], width as low as 10 nm and not more than about 100 nm, Fig. 13B, average thickness around 1 nm. (600 nm)(100 nm)(1 nm)=60,000 nm3.
Gas bubble size: Fan, abstract, nanobubble diameter is about 700 nm. Volume=4/3(pi)r3=179594380 nm3.
Flake size to gas bubble size ratio: 60,000/179594380=0.000334.
Claim 37: agitating the dispersion comprises vibrating the dispersion (Dai, [0019], agitation may comprise sonication to form dispersion).
Claims 5-6, 17, 19-21 and 35-36 are rejected under 35 U.S.C. 103 as being unpatentable over Publication Quantitative Separation of Graphene Oxide Nanoribbon by Froth Flotation (‘Meisam’, Journal of Dispersion Science and Technology, 36:7, 924-931), Publication Effect of nanobubbles on the flotation of different sizes of coal particle (‘Fan’, Minerals & Metallurgical Processing, 2013, Vol. 30, No. 3, pp. 157-161) and U.S. Publication US20190178773A1 (‘Tsai’) as applied to claim 1 above, and further in view of U.S. Publication US20160016796A1 (‘Hersam’).
The Applicant’s claims are directed towards a method.
Regarding Claims 5-6, 17, 19-21 and 35-36, the combination of Meisam, Fan and Tsai teaches the method of Claim 1, except that the flake material has a density which is equal to or lower than a density of the liquid, the flake material has a density which is equal to or higher than a density of the liquid, the flake material has a density which is 70 % - 100 % of the density of the liquid, and flake material has a density which is 100 % - 150 % of the density of the liquid.
Hersam also relates to a method for redistributing a flake material, in particular a two-dimensional nano flake material, into at least two flake size fractions, each of which having smaller flake size variance than the flake material (abstract), wherein the flake material has a density which is equal to or lower than a density of the liquid, the flake material has a density which is equal to or higher than a density of the liquid, the flake material has a density which is 70 % - 100 % of the density of the liquid, and flake material has a density which is 100 % - 150 % of the density of the liquid (Figs. 19A-19B, [0113], density of about 1.0 g/mL).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that the flake material of Meisam, Fan and Tsai can have a density which is equal to or lower than a density of the liquid, which is equal to or higher than a density of the liquid, which is 70 % - 100 % of the density of the liquid and which is 100 % - 150 % of the density of the liquid, as demonstrated by Hersam, because both Meisam and Hersam are concerned with redistributing a flake material, in particular a two-dimensional nano flake material, into at least two flake size fractions, each of which having smaller flake size variance than the flake material, wherein the flake material is nanoribbons (Meisam, abstract and Hersam, [0113]).
Additional Disclosures Included:
Claim 17: said extracting comprises extracting a first flake fraction by extracting the liquid dispersion down to a first vertical level in the container, and subsequently extracting a second flake fraction by further extracting the liquid dispersion down to a second vertical level in the container (Figs. 8A-8C, [0084-0085] and [0075]). (It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention for the extracting of Meisam, Fan and Tsai to comprise extracting a first flake fraction by extracting the liquid dispersion down to a first vertical level in the container, and subsequently extracting a second flake fraction by further extracting the liquid dispersion down to a second vertical level in the container, as demonstrated by Hersam, because nanomaterials in separation fractions can be sufficiently monodisperse and therefore, can be collected as used for processing (Hersam, [0075]). Note that froth flotation comprises extracting a first fraction and extracting a second fraction by further extracting down, as demonstrated by Fan (Fan, Fig. 1, section Experimental).
Claim 19: subjecting an extracted flakes fraction to a second redistribution step comprising: providing a second liquid dispersion of the flake fraction in a second liquid, arranging the second liquid dispersion in a second container, percolating gas bubbles upwardly through the second liquid dispersion, for a time sufficient to allow the flake material in the second liquid dispersion to redistribute itself in the second liquid with larger sized flakes higher up in the liquid and smaller sized flakes lower down in the liquid, and extracting at least one of the flake fractions from a limited vertical level of the second container. (It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention for the method of Meisam, Fan and Tsai to subject an extracted flakes fraction to a second redistribution step, as demonstrated by Hersam (Hersam, [0077] and [0115]), because separation fractions resulting from the second separation cycle can have higher monodispersity compared to the separation fractions resulting from the first separation cycle (Hersam, [0077])).
Claim 20: estimating a flake size or flake size distribution at a selected vertical level in the container, determining whether the flake size or flake size distribution meets a criterion, and if not, then: agitating the dispersion in at least part of the container, repeating the percolating step, repeating the estimating step and repeating the determining step. (It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to estimate a flake size or flake size distribution at a selected vertical level in the container of Meisam, Fan and Tsai, and if not, agitating the dispersion and repeating the separation cycle, as demonstrated by Hersam (Hersam, [0096-0098]), in order to attain significant differentiation (Hersam, [0097], Fig. 17).
Claim 21: agitating the dispersion comprises stirring the dispersion (Tsai, [0005], mixing).
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Publication Quantitative Separation of Graphene Oxide Nanoribbon by Froth Flotation (‘Meisam’, Journal of Dispersion Science and Technology, 36:7, 924-931), Publication Effect of nanobubbles on the flotation of different sizes of coal particle (‘Fan’, Minerals & Metallurgical Processing, 2013, Vol. 30, No. 3, pp. 157-161) and U.S. Publication US20190178773A1 (‘Tsai’) as applied to claim 1 above, and further in view of Publication Highly efficient recovery of graphene oxide by froth flotation using a common surfactant (‘McCoy’, Carbon 135 (2018) 164-170).
The Applicant’s claim is directed towards a method.
Regarding Claim 11, the combination of Meisam, Fan and Tsai teaches the method of Claim 1, except that the flake material is present in the liquid in an amount corresponding to 1 to 4 g/dm3 of the liquid.
McCoy also relates to a method for redistributing a flake material, in particular a two-dimensional nano flake material, into at least two flake size fractions (abstract), wherein the flake material is present in the liquid in an amount corresponding to 1 to 4 g/dm3 of the liquid (section 3. Results and discussion, 1 mg/mL or 1 g/dm3 when converted).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention for the flake material of Meisam, Fan and Tsai to be present in the liquid in an amount corresponding to 1 to 4 g/dm3 of the liquid, as demonstrated by McCoy, because both Meisam and McCoy are concerned with the froth flotation of graphene oxide sheets (Meisam, abstract and McCoy, abstract).
Claim 38 is rejected under 35 U.S.C. 103 as being unpatentable over Publication Quantitative Separation of Graphene Oxide Nanoribbon by Froth Flotation (‘Meisam’, Journal of Dispersion Science and Technology, 36:7, 924-931), Publication Effect of nanobubbles on the flotation of different sizes of coal particle (‘Fan’, Minerals & Metallurgical Processing, 2013, Vol. 30, No. 3, pp. 157-161) and U.S. Publication US20190178773A1 (‘Tsai’) as applied to claim 20 above, and further in view of Publication Effect of frother type and operational parameters on nano bubble flotation of quartz coarse particles (‘Nazari’, Journal of Mining & Environment, Vol.9, No.2, 2018).
The Applicant’s claim is directed towards a method.
Regarding Claim 38, the combination of Meisam, Fan and Tsai teaches the method of Claim 20, except that agitating the dispersion comprises adjusting a supply parameter of the gas bubbles.
Nazari also relates to redistributing a flake material (abstract), including that agitating the dispersion comprises adjusting a supply parameter of the gas bubbles (section 2. Materials and methods).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention that agitating the dispersion of Meisam, Fan and Tsai can comprise adjusting a supply parameter of the gas bubbles, as demonstrated by Nazari, because recovery decreases with air flow due to decrease in bubble sizes (Nazari, section 3.2.3. Effect of air flow rate).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to BOI-LIEN THI NGUYEN whose telephone number is (703)756-4613. The examiner can normally be reached Monday to Friday, 8 am to 6 pm.
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/BOI-LIEN THI NGUYEN/Examiner, Art Unit 1779
/Bobby Ramdhanie/Supervisory Patent Examiner, Art Unit 1779