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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 8/19/2026 has been entered.
Election/Restrictions
Claims 6 and 17-18 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention (17-18) and species (6), there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 10/24/2025.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 1-5, 7, and 13-16 are rejected under 35 U.S.C. 103 as being unpatentable over Zhamu (US 20170225233) in view of Mariusz (GB2541954A), Torobin (US 4303732) and Heston (Heston, The adsorption of hydroxyl ions from aqueous solution on the surface of amorphous silica, The Journal of Physical Chemistry, Vol 65 Issue 1, pg. 147, 1960).
Regarding Claims 1-3, 5, and 7, Zhamu teaches A method of making graphene coated glass microspheres (abstract) comprising: providing Pristine Graphene Particles having an average particle size of from about 200 nm to 20 microns ([0002], [0095]); providing glass microspheres ([0096]) having an average diameter of from about 10 nm to 10 mm and having an external surface (Zhamu Claims 7-8); and mixing the Pristine Graphene Particles with the glass microspheres under conditions to associate the Pristine Graphene Particles on the external surface of the glass microspheres ([0098-0101]). Zhamu teaches the Pristine Graphene Particles are mixed with the hollow glass microspheres under stirring conditions ([0074]). Zhamu teaches impacting balls are optional ([0055]). Zhamu does not teach the carrier particles are broken during preparation.
Zhamu teaches potential applications including heat sinks ([0020]). Zhamu does not explicitly teach the carrier particles being hollow glass microspheres; however, Mariusz teaches graphene coating on hollow glass microspheres for use in heat sink applications wherein the surface of the hollow elements are electrically charged prior to graphene application (abstract, Fig. 3 and discussion thereof, Claim 35). It would have been prima facie obvious to one of ordinary skill in the art at the time of the invention to modify the method of Zhamu to include an electrically charged hollow glass microsphere core, as taught by Mariusz, because it is a known particle for graphene coating in heat sink applications and one of ordinary skill in the art would have had a reasonable expectation of predictably achieving the particles of Zhamu with a hollow glass microsphere core, as in Mariusz.
The combined references are silent as to the wall thickness of the hollow glass microspheres; therefore, one of ordinary skill in the art would have been motivated to look to related art to determine a suitable wall thickness. Torobin teaches hollow glass microspheres having a wall thickness of 0.1 to 1000 microns (Torobin, Claim 1). Torobin teaches, depending on their diameter and wall thickness, the glass microspheres are capable of withstanding relatively high external pressures and/or weight (col. 2 ln. 11-19). It would have been prima facie obvious to one of ordinary skill in the art at the time of the invention to modify the wall thickness of the particles of the combined references to be a thickness, as taught in Torobin, because it is a known wall thickness and one of ordinary skill in the art would have had a reasonable expectation of predictably achieving the particles of the combined references with a wall thickness as in Torobin.
Regarding the claimed particle sizes, “In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).” MPEP 2144.05 I. It would have been prima facie obvious to one of ordinary skill in the art at the time of the invention to select the particle sizes to be any sizes, taught by the references, including those within the claimed range, because the references teach they are all suitable sizes for use with the invention.
Mariusz teaches graphene coating on hollow glass microspheres for use in heat sink applications wherein the surface of the hollow elements are electrically charged prior to graphene application (abstract, Fig. 3 and discussion thereof, Claim 35). The combined references are silent as to the method of charging the glass surfaces; therefore, one of ordinary skill in the art would have been motivated to look to related art to determine a suitable charging method. Heston teaches glass (amorphous silica) is treated with sodium hydroxide at a pH greater than 12 to confer a negative charge and hydroxyl functionality to the glass (abstract, pg. 147 col. 1 1st para., Table 1). It would have been prima facie obvious to one of ordinary skill in the art at the time of the invention to modify the method of the combined references to include a charging method, as taught in Heston, because it is a known method of glass surface charging and one of ordinary skill in the art would have had a reasonable expectation of predictably achieving the charged glass of the combined references with a method as in Heston.
Regarding Claim 4, Mariusz does not explicitly teach a negative charge; however, where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of obviousness has been established, In re Best, 195 USPQ 430, 433 (CCPA 1977).
With regard to the negative charge limitation, when the structure recited in the prior art is substantially identical to that of the claims, the claimed properties or function are presumed inherent. MPEP 2112. In this situation, the prior art exemplifies the applicant's claimed attraction of the graphene material, so the claimed charge relating to the attraction are present in the prior art. Absent an objective evidentiary showing to the contrary, the addition of the physical properties to the claim language fail to provide patentable distinction over the prior art of record.
Regarding Claim 13, Zhamu is silent as to the average graphene coating coverage of the external surface area of the hollow glass microspheres when evaluated by FESEM at 250x magnification; however, Zhamu teaches the graphene proportion is typically from 0.01% to 80% by weight based on the total weight of graphene and inorganic compound ([0053]). Zhamu teaches uniform dispersion of graphene in the composites ([0151]). Graphene proportion necessarily correlates to coating coverage. It would have been prima facie obvious to one of ordinary skill in the art at the time of the invention to modify the method of the combined references to include optimization of the graphene coating coverage, as suggested by Zhamu, in order to achieve a desirable properties, including percolation threshold, in the product composite and in such an optimization one of ordinary skill in the art would have arrived at applicant’s claimed coating coverage.
Regarding Claim 14, Zhamu teaches the Pristine Graphene Particles are mixed with the hollow glass microspheres under stirring conditions ([0074]). Zhamu teaches impacting balls are optional ([0055]). Zhamu does not teach the carrier particles are broken during preparation.
Regarding Claims 15-16, The combined references are silent as to the L*a*b*color value and electrical conductivity of the coated particles; however, where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of obviousness has been established, In re Best, 195 USPQ 430, 433 (CCPA 1977).
With regard to the L*a*b*color value and electrical conductivity limitation, when the structure recited in the prior art is substantially identical to that of the claims, the claimed properties or function are presumed inherent. MPEP 2112. In this situation, the prior art exemplifies the applicant's claimed materials and method , so the claimed properties relating to the particles produced by the claimed materials and method are present in the prior art. Absent an objective evidentiary showing to the contrary, the addition of the physical properties to the claim language fail to provide patentable distinction over the prior art of record.
Claim(s) 8 is rejected under 35 U.S.C. 103 as being unpatentable over Zhamu (US 20170225233), Mariusz (GB2541954A), Torobin (US 4303732) and Heston (Heston, The adsorption of hydroxyl ions from aqueous solution on the surface of amorphous silica, The Journal of Physical Chemistry, Vol 65 Issue 1, pg. 147, 1960) as applied to claims 1-5, 7, and 13-16, and further in view of Zhamu 2 (US 2011/0046027).
Regarding Claim 8, Zhamu teaches wherein the Pristine Graphene Particles have a carbon content of essentially 99% ([0002]), i.e. a non-carbon content of 1% or less.
Zhamu is silent as to the oxygen concentration; therefore, one of ordinary skill in the art would have been motivated to look to related art to determine a suitable impurity concentration. Zhamu 2 teaches pristine graphene with less than 0.05% by weight oxygen ([0023]). It would have been prima facie obvious to one of ordinary skill in the art at the time of the invention to modify the impurities of Zhamu to include an oxygen concentration, as suggested by Zhamu 2, because it is a known concentration in the art and one of ordinary skill in the art would have had a reasonable expectation of predictably achieving the product of Zhamu with an oxygen concentration as in Zhamu 2.
Claim(s) 9-12 are rejected under 35 U.S.C. 103 as being unpatentable over Zhamu (US 20170225233), Mariusz (GB2541954A), Torobin (US 4303732) and Heston (Heston, The adsorption of hydroxyl ions from aqueous solution on the surface of amorphous silica, The Journal of Physical Chemistry, Vol 65 Issue 1, pg. 147, 1960) as applied to claims 1-5, 7, and 13-16, and further in view of Nam (Nam, Monodispersed PtCo nanoparticles on hexadecyltrimethylammonium bromide treated graphene as an effective oxygen reduction reaction catalyst for proton exchange membrane fuel cells, Carbon, 50, 2012, pg. 3739-3747).
Regarding Claims 9 and 11-12, Zhamu teaches functional groups imparted to the graphene in situ, i.e. at the time of mixing, for the purpose of enhancing interfacial bonding ([0077]).
Zhamu does not explicitly teach a hexadecyltrimethylammonium bromide functionalized graphene; however, Nam teaches functionalized graphene for improved adhesion wherein hexadecyltrimethylammonium bromide is used as the functional group (abstract, 2.2). Nam teaches hexadecyltrimethylammonium bromide as an improved functional group compared to covalent bonding groups, which frequently damage graphene properties such as electrical conductivity (1. Introduction last two paragraphs). It would have been prima facie obvious to one of ordinary skill in the art at the time of the invention to modify the functional group of Zhamu to include hexadecyltrimethylammonium bromide, as suggested by Nam, for the benefit of maintaining properties such as electrical conductivity of the graphene.
Regarding Claim 10, Zhamu does not explicitly teach pre-treatment of the graphene; however, Nam teaches pre-treatment before mixing with particles for attachment (2.2). It would have been prima facie obvious to one of ordinary skill in the art at the time of the invention to modify the method of the combined references to include functionalizing before mixing, as suggested by Nam, because it is a known order of steps and one of ordinary skill in the art would have had a reasonable expectation of predictably achieving the product of Zhamu with functionalizing before mixing, as in Nam.
Response to Arguments
Applicant’s arguments, see amendment and remarks, filed 8/19/2026, with respect to the previous prior art rejection of the claims has been fully considered and is not persuasive.
Applicant argues although isolated aspects of the amended claim may be found individually among different references, none of the cited references teaches or suggests the claimed combination of alkaline pretreatment, hydroxyl functionalization, subsequent ionic association of Pristine Graphene Particles, and low-breakage stirring conditions recited in amended independent claim 1. Applicant argues the Office Action does not identify any reference that discloses or suggests this claimed sequence of surface preparation followed by ionic association. Applicant argues Zhamu neither teaches nor suggests the recited sequence of alkaline surface activation followed by ionic association, Heston does not teach treating the hollow glass microspheres to provide both a negative charge and a hydroxyl functionality prior to contact with the Pristine Graphene Particles, Mariusz contains no teaching or suggestion of pretreating hollow glass microspheres to generate hydroxyl-functionalized negatively charged surfaces for subsequent ionic association of preformed Pristine Graphene Particles, and Torobin merely provides a known hollow glass microsphere substrate with no teachings to the recited surface-chemistry- based coating mechanism. In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). Zhamu teaches a method of making Pristine graphene coated glass microspheres and does not teach glass particle breakage occurs, Mariusz teaches graphene coating on hollow glass microspheres for use in heat sink applications wherein the surface of the hollow elements are electrically charged prior to graphene application, Torobin teaches hollow glass microspheres having a wall thickness of 0.1 to 1000 microns, and Heston teaches a method of electrically charging glass (amorphous silica) by treatment with sodium hydroxide at a pH greater than 12 to confer a negative charge and hydroxyl functionality to the glass.
Applicant argues that the Office Action's proposed combination relies upon impermissible hindsight. Applicant argues nothing in Zhamu suggests abandoning its disclosed impact-based transfer process, nothing in Heston suggests using hydroxyl-functionalized silica surfaces to immobilize graphene particles, and neither Mariusz nor Torobin provides any motivation for making these modifications. 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). In response to applicants’ argument, Zhamu teaches impacting balls are optional ([0055]). Mariusz teaches graphene coating hollow glass microspheres by electrical charging prior to graphene application and Heston teaches sodium hydroxide treatment to confer a negative charge to glass.
Applicant argues the proposed combination still would not teach or suggest first hydroxyl-functionalizing the hollow glass microspheres by alkaline pretreatment, thereafter, contacting preformed Pristine Graphene Particles with the treated microspheres, and relying upon ionic interaction under low-breakage stirring conditions to produce the graphene coating. In response to applicant’s argument, Zhamu teaches a method of making Pristine graphene coated glass microspheres and does not teach glass particle breakage occurs, Mariusz teaches graphene coating on hollow glass microspheres for use in heat sink applications wherein the surface of the hollow elements are electrically charged prior to graphene application, Torobin teaches hollow glass microspheres having a wall thickness of 0.1 to 1000 microns, and Heston teaches a method of electrically charging glass (amorphous silica) by treatment with sodium hydroxide at a pH greater than 12 to confer a negative charge and hydroxyl functionality to the glass.
Applicant argues that the cited references do not recognize the breakage problem nor disclose the recited solution. Applicant argues Zhamu relies upon an energy impacting apparatus and one of ordinary skill would therefore have no motivation to replace Zhamu's disclosed impact milling with stirring selected specifically to avoid particle breakage. Applicant argues the Office Action has not identified any teaching or suggestion in the cited references that would have motivated one of ordinary skill in the art to employ stirring conditions specifically selected to maintain breakage below 30% while simultaneously achieving ionic attachment of Pristine Graphene Particles. In response to Applicant's argument, Zhamu teaches impacting balls are optional ([0055]) and does not teach the carrier particles are broken during preparation. In response to applicant's argument that the prior art does not recognize a breakage problem or disclose that no breakage occurs in the stirring, the fact that the inventor has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious. See Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to TABATHA L PENNY whose telephone number is (571)270-5512. The examiner can normally be reached M-F 8:00-5:00.
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/TABATHA L PENNY/Primary Examiner, Art Unit 1712
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