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 .
This action is responsive to Applicant’s amendment/remarks filed 12/04/2025.
Claims 1-9, 11-14, 16, and 18-23 are currently pending.
Response to Amendment
The objection of claims 12 and 20 is withdrawn in view of the above amendment. However, the amendment/claims as presented raise new objectionable issues. See the new claim objections, below.
The amendment also raises new 112(b) indefiniteness issues. See the new 112(b) rejections, below.
The 103 rejections over or based-on Withers et al. (US 6,695,974 B2) or Withers et al. in view of Gogotsi et al. (US 8,137,650 B2) are withdrawn in view of the above amendment.
The 103 rejection over Hwang et al. (US 7,727,414 B2) is withdrawn in view of the above amendment.
The 103 rejections over or based-on Hong et al. (US 8,075,799 B2) or Hong et al. in view of Gogotsi et al. (US 8,137,650 B2) as set forth in the previous Office action mailed 09/05/2025 are maintained and have been revised below to reflect the changes in claim scope made by Applicant’s present claim amendments.
Claim Objections
Claims 5-8 and 21 are objected to because of the following informalities:
Claims 5-8 recite various chemical compounds by their chemical formulae, e.g., “H2SO4”, “H3PO4”, “KMnO4”. The recitations of these chemical formulae are objected to due to the molar/atomic numbers not being in a subscript form, e.g., “H2SO4”, “H3PO4”, “KMnO4”. Applicant is suggested to present the numbers properly as subscripts in order to improve clarity in the claim. Note that the previous set of claims filed on 12/14/2022 correctly recited the numbers as subscripts.
Claim 21 is objected to because the claim fails to end with a period and is therefore not in proper form. Applicant is required to amend the claim such that it properly ends with a period. Each claim begins with a capital letter and ends with a period. Periods may not be used elsewhere in the claims except for abbreviations. See also MPEP 608.01(m).
Appropriate correction is required.
Claim Rejections - 35 USC § 112
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 20, 22, and 23 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 pre-AIA the applicant regards as the invention.
Claim 20 as amended recites, "The nanofluid of claim 1[[7]]13,", indicating the claim is dependent on claim 113. "The nanofluid of claim 1[[7]]13," without the markup reads as "The nanofluid of claim 113,". However, there is no claim 113. The highest claim number is 23. Thus, it is seriously unclear what the claimed nanofluid of claim 20 entails. Appropriate correction is required.
For purposes of compact prosecution of claim 20 (or else claim 20 would not be considered relative to prior art), claim 20 is construed as if it were dependent on claim 13, the independent claim reciting a "nanofluid".
Claim 23 is also indefinite for its dependency on claim 20.
Newly added claim 22 recites “The nanofluid of claim 1,” as its preamble followed by a carbon nanoparticle concentration in its body. However, it is unclear under an indefiniteness rationale whether claim 22 actually further limits and/or includes all the limitations of its parent claim 1 because claim 1 is drawn to a “method” not a “nanofluid”. Claim 1 is a method claim that requires formation of a nanofluid with particular components via particular steps and recitation of a dependent claim to claim 1’s nanofluid (rather than claim 1’s method) renders it unclear if the dependent claim actually requires/includes the particular steps of the parent claim.
For further examination of claim 22, claim 22 is construed as if it recited “The method of claim 1”. However, Applicant is cautioned that an amendment to claim 22 to recite “The method of claim 1” would cause claim 22 to be a substantial duplicate of claim 21 (see 37 CFR 1.75 and MPEP § 608.01(m)).
Appropriate correction/clarification is required.
Claim Interpretation
The claim interpretation set forth in the previous Office action mailed 09/05/2025 still applies:
The claims generally recite nanofluid compositions and methods of preparing nanofluid compositions comprising “carbide-derived carbon nanoparticles” as a component therein. While the component must contain some sort of “carbon nanoparticles”, the term “carbide-derived” describes a process of how the carbon nanoparticles are prepared and therefore constitutes a product-by-process limitation. Product-by-process limitations do not require the recited steps except to the extent they suggest structure of the product.
In the instant case, the “carbide-derived carbon nanoparticles” is a very broad limitation that does not necessarily require the carbon nanoparticles actually be made from a carbide-containing/based precursor. Note the specification provides very few, if any, details to specific structure(s) required by the recited product-by-process limitation that the carbon nanoparticles are “carbide-derived”; [0036] appears to be the only description of and it is very open-ended: “Carbide-derived carbon (CDC) is a carbon generation material that has a wide range of properties depending on experimental conditions. It is a nanoporous carbon derived from different precursors such as SiC, TiC, and polymer derived ceramics such as Ti-C or Si-O-C. CDC is a material with an amorphous to crystalline structure demonstrating unique properties which can include: high specific surface area, high stability, controllable pore size distribution and conductivity.” For purposes of further examination, carbon nanoparticles having any one or more of nano/mesoporosity, a relatively or even subjectively high specific surface area, a relatively or even subjectively high stability, a controllable pore size distribution, or conductivity very fairly read on the claimed “carbide-derived carbon nanoparticles” per Applicant’s broad, open-ended discussion of structure that carbide-derived carbon nanoparticles may exhibit. Alternatively, carbon nanoparticles comprising some portion of a carbide or carbon nanoparticles explicitly taught as comprising a carbide in its precursor of course also reads on the claimed “carbide-derived carbon nanoparticles” even if it does not explicitly or even intrinsically have the property(ies) listed by Applicant in the specification.
"[E]ven though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process." In re Thorpe, 777 F.2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985).
The structure implied by the process steps should be considered when assessing the patentability of product-by-process claims over the prior art, especially where the product can only be defined by the process steps by which the product is made, or where the manufacturing process steps would be expected to impart distinctive structural characteristics to the final product. See, e.g., In re Garnero, 412 F.2d 276, 279, 162 USPQ 221, 223 (CCPA 1979).
"The Patent Office bears a lesser burden of proof in making out a case of prima facie obviousness for product-by-process claims because of their peculiar nature" than when a product is claimed in the conventional fashion. In re Fessmann, 489 F.2d 742, 744, 180 USPQ 324, 326 (CCPA 1974). Once the examiner provides a rationale tending to show that the claimed product appears to be the same or similar to that of the prior art, although produced by a different process, the burden shifts to applicant to come forward with evidence establishing an nonobvious difference between the claimed product and the prior art product. In re Marosi, 710 F.2d 799, 803, 218 USPQ 289, 292-33 (Fed. Cir. 1983).
"[T]he lack of physical description in a product-by-process claim makes determination of the patentability of the claim more difficult, since in spite of the fact that the claim may recite only process limitations, it is the patentability of the product claimed and not of the recited process steps which must be established. We are therefore of the opinion that when the prior art discloses a product which reasonably appears to be either identical with or only slightly different than a product claimed in a product-by-process claim, a rejection based alternatively on either section 102 or section 103 of the statute is eminently fair and acceptable. As a practical matter, the Patent Office is not equipped to manufacture products by the myriad of processes put before it and then obtain prior art products and make physical comparisons therewith." In re Brown, 459 F.2d 531, 535, 173 USPQ 685, 688 (CCPA 1972).
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.
Claims 1-4, 11, 13, 14, 16, 18, 19, 21, and 22 are rejected under 35 U.S.C. 103 as being unpatentable over Hong et al. (US 8,075,799 B2) or Hong et al. in view of Gogotsi et al. (US 8,137,650 B2).
As to claim 1, Hong et al. teach a process for producing a nanofluid (abstract). The nanofluid comprises carbon nanoparticles and a surfactant in a base fluid (thermal transfer fluid) (abstract). The nanofluid is made by dispersing a mixture of the carbon nanoparticles in the base fluid by a physical mixing method, such as sonication (ultrasonication) to form a stable suspension (col. 12 line 62 to col. 13 line 5) which reads on the claimed steps of mixing a predetermined amount of carbon nanoparticles in a base fluid thereby forming a mixture and subjecting the mixture to sonication for a predetermined amount of time. If this were not enough, see the carbon nanoparticle concentrations at col. 13 line 65 to col. 14 line 4 that certainly read on a predetermined amount of carbon nanoparticles and the ultrasonication times at col. 13 lines 6-27 that certainly read on a sonication for a predetermined amount of time; see also the working examples. Hong et al. further teach the carbon nanoparticles may be present in an amount within 0-30 wt.% of the nanofluid and subsets thereof, e.g., 0-10 wt.%, 0-2.5 wt.%, 0-5 wt.%, etc. (col. 13 line 65 to col. 14 line 4) that overlaps and encompasses the claimed 0.05 to 0.3 wt.% range.
Besides Hong et al. teaching their concentration of carbon nanoparticles in overlapping amounts (rather than anticipatory amounts), the only difference between Hong et al. and the claimed method is that Hong et al. does not exemplify the carbon nanoparticles are “carbide-derived carbon nanoparticles” under the meaning of anticipation.
However, at the time of the effective filing date it would have been obvious to a person of ordinary skill in the art to provide and/or arrive at the claimed limitation that the carbon nanoparticles are “carbide-derived” as Hong et al. teaches selecting various carbon nanoparticles for inclusion in their fluid, including carbon nanotubes that may encapsulate various elements and/or molecules within their structure including, among others, carbide compounds in order to enhance the thermal conductivity of the nanotubes (col. 5 lines 34-46). Carbon nanotubes having a carbide encapsulated therein read on the claimed “carbide-derived carbon nanoparticles”. This rejection is only made under an obviousness rationale because there are a number of carbon nanoparticles encompassed by the reference (see, e.g., col. 4 line 43+) such that a carbide-derived carbon nanoparticle requires selection from a list/genera of alternatives rather than would be at once envisaged from a short list of alternatives.
Alternatively regarding the claimed carbide-derived carbon nanoparticles, note that carbon nanotubes, such as single wall carbon nanotubes (SWNTs) are generally one of Hong et al.’s preferred carbon nanoparticles for the nanofluid (Id. such as col. 4 lines 44-50 and col. 6 lines 36-44). However, note that Gogotsi et al. teach a nanoporous carbide-derived carbon (abstract) where, because of their tunable porous structures, controlled surface chemistry, and other properties, they may be used in applications where single wall carbon nanotubes are provided (col. 5 lines 46-60). In other words, Gogosti et al. recognize and teach provision of carbide-derived carbon as a suitable alternative to single wall carbon nanotubes.
Accordingly, alternative to Hong et al.’s own carbide-derived/containing/based carbon nanoparticles, at the time of the effective filing date it would have also been obvious to a person of ordinary skill in the art to provide Gogotsi et al.’s carbide-derived carbon as the carbon nanoparticle of Hong et al. in order to obtain a nanofluid with a reasonable expectation of success because Gogotsi et al. strongly teach and motivate substitution of carbide-derived carbon in place of single wall carbon nanotubes.
As to claim 2, Hong et al. teach water is a preferred base fluid (col. 3 lines 25-26).
As to claims 3 and 4, Hong et al. teach the carbon nanoparticles may be functionalized that affects the hydrophilicity of the carbon nanoparticles (col. 5 line 47 to at least col. 6 line 50) and may contain a carboxyl group as the functionalization (col. 5 line 47 to col. 6 line 10). Carbon nanoparticles functionalized with carboxyl groups are indeed functionalized with a carboxylation process as claimed and the functionalization would need to occur prior to the mixing in making the nanofluid as claimed.
As to claim 11, Hong et al. teach the carbon nanoparticles may be present in an amount within 0-30 wt.% of the nanofluid and subsets thereof, e.g., 0-10 wt.%, 0-2.5 wt.%, 0-5 wt.%, etc. (Id., e.g., col. 13 line 65 to col. 14 line 4) and the surfactant may be present in an amount within 0-10 wt.% of the nanofluid and subsets thereof, e.g., 0-1 wt.%, or 0.1-30 wt.% of the nanofluid and subsets thereof, e.g., 1-20 wt.%, 1-10 wt.%, etc. (col. 14 lines 5-11). While Hong et al. fail to meet the claimed relative weight amounts/ratios of carbon nanoparticles to surfactant of 1:1 or 1:2 under the meaning of anticipation, the concentrations of carbon nanoparticles and surfactant permitted by Hong et al.’s ranges of the components overlap and encompass the claimed 1:1 or 1:2 relative weight amounts/ratios.
As to claims 21 and 22, Hong et al. teach the carbon nanoparticles may be present in an amount within 0-30 wt.% of the nanofluid and subsets thereof, e.g., 0-10 wt.%, 0-2.5 wt.%, 0-5 wt.%, etc. (Id.) that overlaps and encompasses the claimed 0.1 to 0.3 wt.% range.
As to claim 13, Hong et al. teach a nanofluid comprising carbon nanoparticles and a surfactant in a base fluid (thermal transfer fluid) (abstract). The nanoparticles are stably suspended in the nanofluid (col. 12 line 62 to col. 13 line 5). The nanoparticles may very clearly be functionalized (col. 5 line 47 to at least col. 6 line 50). Hong et al. further teach the carbon nanoparticles may be present in an amount within 0-30 wt.% of the nanofluid and subsets thereof, e.g., 0-10 wt.%, 0-2.5 wt.%, 0-5 wt.%, etc. (col. 13 line 65 to col. 14 line 4) that overlaps and encompasses the claimed 0.05 to 0.3 wt.% range.
Besides Hong et al. teaching their concentration of carbon nanoparticles in overlapping amounts (rather than anticipatory amounts), the only difference between Hong et al. and the claimed method is that Hong et al. does not exemplify the carbon nanoparticles are “carbide-derived carbon nanoparticles” under the meaning of anticipation.
However, at the time of the effective filing date it would have been obvious to a person of ordinary skill in the art to provide and/or arrive at the claimed limitation that the carbon nanoparticles are “carbide-derived” as Hong et al. teaches selecting various carbon nanoparticles for inclusion in their fluid, including carbon nanotubes that may encapsulate various elements and/or molecules within their structure including, among others, carbide compounds in order to enhance the thermal conductivity of the nanotubes (col. 5 lines 34-46). Carbon nanotubes having a carbide encapsulated therein read on the claimed “carbide-derived carbon nanoparticles”. This rejection is only made under an obviousness rationale because there are a number of carbon nanoparticles encompassed by the reference (see, e.g., col. 4 line 43+) such that a carbide-derived carbon nanoparticle requires selection from a list/genera of alternatives rather than would be at once envisaged from a short list of alternatives.
Alternatively regarding the claimed carbide-derived carbon nanoparticles, note that carbon nanotubes, such as single wall carbon nanotubes (SWNTs) are generally one of Hong et al.’s preferred carbon nanoparticles for the nanofluid (Id. such as col. 4 lines 44-50 and col. 6 lines 36-44). However, note that Gogotsi et al. teach a nanoporous carbide-derived carbon (abstract) where, because of their tunable porous structures, controlled surface chemistry, and other properties, they may be used in applications where single wall carbon nanotubes are provided (col. 5 lines 46-60). In other words, Gogosti et al. recognize and teach provision of carbide-derived carbon as a suitable alternative to single wall carbon nanotubes.
Accordingly, alternative to Hong et al.’s own carbide-derived/containing/based carbon nanoparticles, at the time of the effective filing date it would have also been obvious to a person of ordinary skill in the art to provide Gogotsi et al.’s carbide-derived carbon as the carbon nanoparticle of Hong et al. in order to obtain a nanofluid with a reasonable expectation of success because Gogotsi et al. strongly teach and motivate substitution of carbide-derived carbon in place of single wall carbon nanotubes.
As to claim 14, Hong et al. teach water is a preferred base fluid (col. 3 lines 25-26).
As to claim 16, Hong et al. teach the carbon nanoparticles may be present in an amount within 0-30 wt.% of the nanofluid and subsets thereof, e.g., 0-10 wt.%, 0-2.5 wt.%, 0-5 wt.%, etc. (Id.) that overlaps and encompasses the claimed 0.3 wt.% amount.
As to claims 18 and 19, Hong et al. teach the carbon nanoparticles may be present in an amount within 0-30 wt.% of the nanofluid and subsets thereof, e.g., 0-10 wt.%, 0-2.5 wt.%, 0-5 wt.%, etc. and the surfactant may be present in an amount within 0-10 wt.% of the nanofluid and subsets thereof, e.g., 0-1 wt.%, or 0.1-30 wt.% of the nanofluid and subsets thereof, e.g., 1-20 wt.%, 1-10 wt.%, etc. (Id.). While Hong et al. fail to meet the claimed relative weight amounts/ratios of carbon nanoparticles to surfactant of 1:1 or 1:2 under the meaning of anticipation, the concentrations of carbon nanoparticles and surfactant permitted by Hong et al.’s ranges of the components overlap and encompass the claimed 1:1 or 1:2 relative weight amounts/ratios.
Claims 5-9 are rejected under 35 U.S.C. 103 as being unpatentable over Hong et al. (US 8,075,799 B2) or Hong et al. in view of Gogotsi et al. (US 8,137,650 B2) as applied to claims 1-4, 11, 13, 14, 16, 18, 19, 21, and 22 above, and further in view of Al-Gaashani et al. (“XPS and structural studies of high quality graphene oxide and reduced graphene oxide prepared by different chemical oxidation methods”, Ceramics International, 45, 2019, 14439-14448).
The disclosures of Hong et al. and Hong et al. in view of Gogotsi et al. are relied upon as set forth above. Hong et al. and Hong et al. in view of Gogotsi et al. teach nanofluids and methods of making thereof comprising carboxyl-functional carbide-derived carbon nanoparticles, as described above.
As to claims 5 and 9, while Hong broadly teach the carbon nanoparticles may be chemically functionalized with, for example, carboxyl groups which encompass a carboxylation process (Id.), the references fail to teach or meet the specific sequence of steps as instantly claimed.
However, Al-Gaashani et al. teach a process of chemically oxidizing carbon nanoparticles via an acid-based process in order to functionalize the carbon nanoparticles with carboxyl groups (abstract and Fig. 1), i.e., a carboxylation process. Per § 2.2 and 2.3 on p.14442 to 14445 of Al-Gaashani et al., the process comprises a sequence of the following steps:
1) dispersing carbon particles in an acid mixture comprising H2SO4 and H3PO4 and stirring to form a mixture/dispersion (this step would obviously occur while the acid mixture is positioned in an ice bath as the left col. of p.14442 teaches temperature was maintained below 5°C during the addition of different reactants with the use of ice baths),
2) slowly add KMnO4 to the mixture while maintaining the temperature below 5°C using an ice bath (a person of ordinary skill in the art would obviously continue stirring the mixture from the prior step for the added permanganate to be dispersed/reacted; if this were not enough, it is later described in the left col. of p.14443 that stirring occurs throughout the experiment),
3) positioning the mixture in an oil bath at a temperature of 45±5°C for 2h (a person of ordinary skill in the art would obviously continue stirring from the prior steps for the reactants to be sufficiently mixed/dispersed/reacted; in any event, the reference otherwise teach stirring occurs throughout the experiment, Id.),
4) positioning the mixture back in the ice bath and adding deionized water,
5) positioning the mixture back in the oil bath at a temperature at 85°C for 1h (a person of ordinary skill in the art would obviously continue stirring from the prior steps for the reactants to be sufficiently mixed/dispersed/reacted; in any event, the reference otherwise teach stirring occurs throughout the experiment, Id.),
6) adding deionized water and H2O2 to the mixture (the addition obviously occurs while the mixture is positioned in the ice bath as the left col. of p.14442 teaches temperature was maintained below 5°C during the addition of different reactants with the use of ice baths, Id.),
7) washing the mixture with HCl,
8) centrifuging the mixture,
9) repeating the washing many times with deionized water to wash out the acid while continually checking the pH and stopping washing once the solution reaches a neutral pH (i.e., 7). While Al-Gaashani et al. does not explicitly teach isolating or drying the finally obtained neutral suspension, carbon nanoparticles can obviously be isolated by drying the obtained suspension consisting of carbon nanoparticles and water. If this were not enough, while not explicitly taught Al-Gaashani et al. nevertheless implicitly require some sort of isolating/drying after the described process as Al-Gaashani et al. perform various studies on the obtained carbon nanoparticles (SEM, XPS, etc.) that would require a dry, isolated product. The carboxylation process steps taught by Al-Gaashani et al. directly read on and correspond to the carboxylation process steps instantly claimed.
At the time of the effective filing date it would have been obvious to a person of ordinary skill in the art to provide the acid-based oxidation/carboxylation process taught by Al-Gaashani et al. as the carboxyl-functionalizing process of Hong et al. and Hong et al. in view of Gogotsi et al. in order to obtain a nanofluid having sufficiently dispersed/suspended carboxyl-functional carbon nanoparticles with a reasonable expectation of success.
As to claim 6, note that Example 1 in Al-Gaashani et al. provides a 70:20 mixture of H2SO4 and H3PO4 (§ 2.2) while Example 2 in Al-Gaashani et al. provides a 90:10 mixture of H2SO4 and H3PO4 (§ 2.3). While these mixtures do not precisely correspond to the claimed volumetric ration of 60:40 H2SO4:H3PO4, they nevertheless demonstrate the ratio of the acids may be sufficiently varied and still obtain a carboxyl-functional carbon nanomaterial. At the time of the effective filing date it would have been obvious to a person of ordinary skill in the art to vary/tailor the relative amount of H2SO4 and H3PO4 in order to obtain an oxidized/carboxyl-functional carbon nanomaterial with a reasonable expectation of success.
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) (Claimed process which was performed at a temperature between 40°C and 80°C and an acid concentration between 25% and 70% was held to be prima facie obvious over a reference process which differed from the claims only in that the reference process was performed at a temperature of 100°C and an acid concentration of 10%.). See also Peterson, 315 F.3d at 1330, 65 USPQ2d at 1382 ("The normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages."). See also In re Hoeschele, 406 F.2d 1403, 160 USPQ 809 (CCPA 1969) (Claimed elastomeric polyurethanes which fell within the broad scope of the references were held to be unpatentable thereover because, among other reasons, there was no evidence of the criticality of the claimed ranges of molecular weight or molar proportions.).
As to claims 7 and 8, note the steps “3)” and “5)” above where 3) positions the mixture in an oil bath at a temperature of 45±5°C for 2h and stirs and 5) positions the mixture back in the oil bath at a temperature at 85°C for 1h and stirs (Id.). “3)” reads on stirring the mixture in the oil bath at the recited temperature of claim 7 but falls short of the claimed time (2h disclosed but 2.5h claimed). “5)” reads on stirring the mixture in the oil bath at the recited temperature of claim 8 but falls short of the claimed time (1h disclosed but 2h claimed). However, these minor differences in duration do not patentably distinguish over the reference(s) and the differences in duration would nevertheless have been obvious to a person of ordinary skill in the art. Absent of a showing to the contrary, it would have been obvious to a person of ordinary skill in the art to stir the mixture for a longer duration in order to ensure sufficient dispersion, mixing, and/or reaction with a reasonable expectation of success.
Claims 12, 20, and 23 are rejected under 35 U.S.C. 103 as being unpatentable over Hong et al. (US 8,075,799 B2) or Hong et al. in view of Gogotsi et al. (US 8,137,650 B2) as applied to claims 1-4, 11, 13, 14, 16, 18, 19, 21, and 22 above, and further in view of Rashmi et al. (“Stability and thermal conductivity enhancement of carbon nanotube nanofluid using gum arabic,” Journal of Experimental Nanoscience, 6:6, 2011, 567-579) or Alvarado et al. (US 2011/0220840 A1).
The disclosures of Hong et al. and Hong et al. in view of Gogotsi et al. are relied upon as set forth above. Hong et al. and Hong et al. in view of Gogotsi et al. teach nanofluids and methods of making thereof comprising carbide-derived carbon nanoparticles and a surfactant, as described above.
As to claims 12 and 20, while Hong et al. teach various compounds for provision as a surfactant (Id.; see col. 8 line 13 to col. 11 line 32), the references fail to specify the surfactant is gum arabic, as claimed.
However, Rashmi et al. teach nanofluids that comprise carbon nanoparticles and water, with and without gum arabic as a dispersant therein (abstract). Rashmi et al. demonstrates the nanofluids exhibit improved stability, i.e., prevention of the carbon nanoparticles from aggregation and formation of clusters, when they contain gum arabic versus when the nanofluids exclude gum arabic without detrimentally impacting the thermal conductivity of the nanofluid (abstract and conclusion section on p.577).
Accordingly, at the time of the effective filing date it would have been obvious to a person of ordinary skill in the art to provide gum arabic as taught by Rashmi et al. as the surfactant in Hong et al. or in Hong et al. in view of Gogotsi et al. in order to obtain a nanofluid having sufficiently dispersed/suspended carbon nanoparticles with an improved stability with a reasonable expectation of success.
Alternatively, Alvarado et al. teach nanofluids that comprise carbon nanoparticles and a surfactant mixed into a fluid such as water (abstract) where gum arabic is provided as the surfactant (abstract and para. 0024). Alvarado et al. teach surfactants changes the surface wetting or adhesion behavior of carbon nanoparticles reducing the tendency for the carbon nanoparticles to self-agglomerate or clump and to sufficiently disperse the carbon nanoparticles (para. 0003).
Accordingly, at the time of the effective filing date it would have been obvious to a person of ordinary skill in the art to provide gum arabic as taught by Alvarado et al. as the surfactant in Hong et al. or in Hong et al. in view of Gogotsi et al. in order to obtain a nanofluid having sufficiently dispersed/suspended carbon nanoparticles with a reduced tendency to self-agglomerate or clump with a reasonable expectation of success.
As to claim 23, Hong et al. teach the carbon nanoparticles may be present in an amount within 0-30 wt.% of the nanofluid and subsets thereof, e.g., 0-10 wt.%, 0-2.5 wt.%, 0-5 wt.%, etc. (Id.) that overlaps and encompasses the claimed 0.3 wt.% amount.
Response to Arguments
Applicant's arguments filed 12/04/2025 have been fully considered but they are not persuasive.
Regarding the 103 rejections based on Hong et al. (US 8,075,799 B2) Applicant argues the specification demonstrates the claimed nanofluids comprising carbide-derived nanoparticles at a concentration of 0.05-0.3% by weight and a surfactant possess enhanced properties of an increased viscosity and thermal conductivity.
In response, while obviousness rejections can be withdrawn if there is a showing that a concentration is critical or possesses unexpected results, Applicant’s argument and the comparative showing of record is insufficient to withdraw the 103 rejections of record because superiority (i.e., enhanced properties) alone is not sufficient to show that the result is unexpected, Pfizer, Inc. v. Apotex, Inc., 480 F.3d 1348, 1371 (Fed. Cir. 2007) (“[A]ny superior property must be unexpected to be considered as evidence of non-obviousness.”), Applicant has not provided evidence of the unexpected nature of the observed results.
Additionally, to establish the existence of unexpected results, Applicant must establish through the introduction of evidence both that (1) there is actually a difference between the results obtained through the claimed invention and those of closest prior art and (2) the observed difference would have been unexpected by a person having ordinary skill in the art. In re Freeman, 474 F.2d 1318, 1324 (CCPA 1973). In this case, Applicant has not provided evidence that, as of the application's effective filing date, a person having ordinary skill in the art would have considered the results presented in the data to have been unexpected or surprising. The arguments do not cite evidence regarding the unexpected nature of the observed differences.
Applicant has also not demonstrated the claimed concentration range is critical. To establish unexpected results over a claimed range, applicants should compare a sufficient number of tests both inside and outside the claimed range to show the criticality of the claimed range. In re Hill, 284 F.2d 955, 128 USPQ 197 (CCPA 1960).
While Applicant also contends Hong et al. does not disclose the claimed weight percentage of carbide-derived carbon nanoparticles alongside a surfactant, this is not persuasive because Hong et al. teach a surfactant is a required component of their composition per the abstract, Hong et al. teach the carbon nanoparticles may be present in an amount within 0-30 wt.% of the nanofluid and subsets thereof, e.g., 0-10 wt.%, 0-2.5 wt.%, 0-5 wt.%, etc. (col. 13 line 65 to col. 14 line 4) that overlaps and encompasses the claimed 0.05 to 0.3 wt.% range, and Applicant has ultimately not perfected a showing of unexpected results commensurate in scope with the claims.
Applicant further argues Hong et al. fails to teach or suggest carbide-derived carbon nanoparticles.
In response, this argument is not persuasive because Hong et al. indeed teach carbon nanoparticles that read on the claimed “carbide-derived carbon nanoparticles”. As thoroughly described in the Claim Interpretation sections of record, the “carbide-derived carbon nanoparticles” is a very broad, open-ended product-by-process limitation that does not necessarily require the carbon nanoparticles actually be made from a carbide-containing/based precursor. Please see the Claim Interpretation sections of record. However, commensurate under the broadest reasonable interpretation of the claimed “carbide-derived carbon nanoparticles”, Hong et al. teaches selecting various carbon nanoparticles for inclusion in their fluid, including carbon nanotubes that may encapsulate various elements and/or molecules within their structure including, among others, carbide compounds in order to enhance the thermal conductivity of the nanotubes (col. 5 lines 34-46). Carbon nanotubes having a carbide encapsulated therein as taught by Hong et al. read on and meet the claimed “carbide-derived carbon nanoparticles”.
In any event, in response to Applicant's arguments against the Hong et al. reference individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. The rejection also optionally relies on Gogotsi et al. (US 8,137,650 B2) as a secondary reference combined with Hong et al. which sets forth a rationale that at the time of the effective filing date it would have also been obvious to a person of ordinary skill in the art to provide Gogotsi et al.’s carbide-derived carbon as the carbon nanoparticle of Hong et al. in order to obtain a nanofluid with a reasonable expectation of success because Gogotsi et al. strongly teach and motivate substitution of carbide-derived carbon in place of single wall carbon nanotubes. 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).
Accordingly, the rejection is maintained for the reasons of record.
The remaining references listed on Forms 892 and 1449 have been reviewed by the examiner and are considered to be cumulative to or less material than the prior art references relied upon or described above.
Conclusion
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.
Correspondence
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/MATTHEW R DIAZ/Primary Examiner, Art Unit 1761
/M.R.D./
February 11, 2026