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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 June 12, 2026 has been entered.
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 2-22 are rejected under 35 U.S.C. 103 as being unpatentable over Naskar (US 2014/0265038 A1) in view of Xue (Nano Research 2009, 2, 242-253). Soehngen (US Patent Number 4,020,145) is included as an evidentiary reference.
Regarding claim 2, Naskar teaches a method for preparing carbon fibers from a fiber precursor (Abstract). The carbon fibers of Naskar read on the claimed “structure” because the instant Specification states that the structure may be a fiber (see instant Specification at [0060]). The fiber precursors of Naskar read on the claimed “template structure,” because Naskar teaches that the precursor fibers are converted into the carbon fiber structure (Abstract) – i.e., the precursors are templating the structure of the final material. Naskar further teaches that the fibers are carbonized and undergo thermo-oxidative crosslinking ([0054]), which reads on the claimed “carbonized material” as well as the limitation that the material has been crosslinked. Naskar also teaches that the fibers are produced from a precursor fiber ([0002]), which is made from a polymer ([0044]) which reads on the claimed “shape based on a polymer based template structure.”
Naskar differs from claim 2 because it is silent with regard to the incorporation of a resol coating from which the carbonized material is formed. Naskar does however explicitly state that the precursor fibers may have any composition known in the art prior as being capable of producing a carbon fiber upon carbonization ([0044]).
In the same field of endeavor, Xue teaches a macro-mesoporous structure produced from the carbonization of a polyurethane foam which has been coated in a phenol/formaldehyde resin (Abstract). Xue explicitly teaches that the phenol/formaldehyde resin is a carbon precursor (Abstract). It is prima facie obvious to select a known material based on its art-recognized suitability for its intended use (See MPEP 2144.07). Therefore, it would have been obvious to one of ordinary skill in the art before the time of filing to incorporate the phenol/formaldehyde coating of Xue into the polymer fibers of Naskar, as Xue recognizes phenol/formaldehyde resin as suitable for the production of a carbonized coating, which would hold true for the coating of any applicable structure. Xue further specifies that the phenol/formaldehyde (resol) coating is supplied as an ethanolic solution which coats the sample including the interior portion of the structure thereof (p. 245, Scheme 1), which prima facie will have the same effect as submerging the sample in the solution. The ethanol is subsequently evaporated, and the coated sample is heated, optionally to 130°C for 3 hours for thermopolymerization/calcination (p. 244, 1.3 Synthesis of Monoliths section). It therefore would have been obvious to one having ordinary skill in the art to heat the resol-coated carbon fibers of Naskar to this same temperature range for this same time frame for the purpose of thermopolymerizing/calcining the resol coating. As the applicant has argued in the response filed June 12, 2026, the process contemplated within the specification indicates that solvent evaporation and thermal heating to between 100 and 150°C for between 2 and 24 hours effects resol crosslinking (c.f. instant Specification at [0062]). The time and temperature values above fall within these ranges. Meanwhile, Xue specifically states contemplates thermopolymerizing/calcining and carbonization as separate steps (c.f. p. 244-245, 2.1 Fabrication of the Hierarchically Porous Monolith Materials section). The process of Naskar as modified by Xue therefore is substantially identical to the process within the instant Specification, and, prima facie, will result in the claimed “cross-linked resol coating.”
Regarding claims 3 and 4, Naskar teaches that the resulting carbonized carbon fiber has a surface area ranging from 5 to 3,000 m2/g ([0029]), which encompasses the claimed ranges of “about 2500 m2/g to about 2700 m2/g” and “about 500 m2/g to about 2500 m2/g,” establishing prima facie cases of obviousness. Naskar differs from claims 3 and 4 because it is silent with regard to the claimed average pore volumes. However, Naskar teaches that the surface area is strongly dependent on the level of porosity of the carbon fibers ([0029]). Naskar further teaches that the carbonized carbon fibers may be microporous, mesoporous, or microporous ([0025]), and teaches that mesopores may range from 2-50 nm in diameter ([0026]). These diameters correspond to a similar range expressed in the instant Specification as capable of producing the claimed “average pore volume” (c.f. Figure 19 of the instant Specification, which shows a distribution of pore widths in nm which roughly corresponds to the same range of mesopore sizes taught by Naskar). Naskar recognizes the pore size of a carbon fiber as a result-effective variable in tuning the surface area of said carbon fiber. Additionally, as expressed above, Naskar teaches a range of surface areas which encompasses (and therefore, surpasses) the maximum surface areas required by claims 3 and 4. It would therefore be obvious to one of ordinary skill in the art to perform routine optimization on the level of porosity of the carbon fiber for the purpose of achieving the range of surface areas taught by Naskar. The ranges of surface areas and pore volumes taught by Naskar, respectively, encompass and align with those of the instant claim set and Specification. Thus, It would be obvious for one of ordinary skill in the art to reach the claimed ranges of pore volumes within the teachings of Naskar.
Regarding claim 5, the claim is recognized as a product-by-process claim. Product-by-process claims are limited not by the process, but only by product structure implied by the process. In the case of claim 5, the product (i.e., the claimed “carbonized materials”) are limited by the structure implied by the process of producing the crosslinked structure as shown. In other words, prior art which may read on the claim will do so regardless of the provision of an identical chemical structure image, so long as the process steps taught by the prior art imply the same structural changes in the product. In the case of claim 5 in view of the instant Specification, the carbonized material is produced by sulfonating a polypropylene polymer, followed by a crosslinking (comprising olefination and addition/rearrangement) of the resulting sulfonated polypropylene to achieve the desired structure (c.f. instant Specification, Figure 8, as well as [0065] and [0067]). The instant Specification states that fuming sulfuric acid may be used for this process (see instant Specification at [0068]). Further, the instant specification supports simultaneous crosslinking and sulfonation steps (c.f. instant Specification at [0068]), which may be affected by submerging a polypropylene structure in sulfuric acid at an elevated temperature (100°C to 200°C) for a specified period of time (about 15 minutes to about 72 hours). Most saliently, the instant Specification states that a polypropylene structure may be effectively crosslinked during the sulfonation step (see instant Specification at [0068]). Thus, the claimed structure is reasonably expected to be achieved if a polypropylene structure is exposed to a substantially similar sulfonation process.
Naskar teaches that the inventive carbon fibers may be formed from polypropylene ([0044]), and teaches that the fibers may be subjected to chemical stabilization, and more particularly to a liquid-immersion sulfonation process ([0049]), as described in Soehngen, the subject matter of which is included within Naskar in its entirety by reference ([0049]). This sulfonation process involves the same kind of acid solution (fuming sulfuric acid), an overlapping temperature range (up to 100°C), and overlapping reaction times (30 to 400 minutes) (c.f. Soehngen, col. 5, lines 53-60), and is taught by Naskar to envision liquid-immersion ([0049]).
Thus, Naskar teaches a carbonized polypropylene which has been crosslinked via a sulfonation process (one substantially similar to the one described), and which therefore includes all of the structures implied by the product-by-process limitations of claim 5. The carbon fiber precursor materials taught by Naskar therefore read on the claimed “cross-linked polyolefin based structure” with the claimed chemical structure.
Regarding claim 6, Naskar teaches that the resulting carbonized carbon fiber has a surface area ranging from 5 to 3,000 m2/g ([0029]), which encompasses the claimed range of “about 250 m2/g to about 700 m2/g,” establishing a prima facie case of obviousness. Naskar differs from claim 6 because it is silent with regard to the claimed average pore volumes. However, Naskar teaches that the surface area is strongly dependent on the level of porosity of the carbon fibers ([0029]). Naskar further teaches that the carbonized carbon fibers may be microporous, mesoporous, or microporous ([0025]), and teaches that mesopores may range from 2-50 nm in diameter ([0026]). These diameters correspond to a similar range expressed in the instant Specification as capable of producing the claimed “average pore volume” (c.f. Figure 19 of the instant Specification, which shows a distribution of pore widths in nm which roughly corresponds to the same range of mesopore sizes taught by Naskar). Naskar recognizes the pore size of a carbon fiber as a result-effective variable in tuning the surface area of said carbon fiber. Additionally, as expressed above, Naskar teaches a range of surface areas which encompasses (and therefore, surpasses) the maximum surface area required by claim 6. It would therefore be obvious to one of ordinary skill in the art to perform routine optimization on the level of porosity of the carbon fiber for the purpose of achieving the range of surface areas taught by Naskar. The ranges of surface areas and pore volumes taught by Naskar, respectively, encompass and align with those of the instant claim set and Specification. Thus, It would be obvious for one of ordinary skill in the art to reach the claimed ranges of pore volume within the teachings of Naskar.
Regarding claim 7, Naskar teaches that the carbonized fibers may be formed from polyolefins such as polyethylene and polypropylene ([0044]), and also teaches that the polymers which form the carbon fibers may be stabilized via a sulfonation process prior to carbonization ([0049]); the teachings of Naskar therefore read on the claimed “sulfonated polyolefin.”
Regarding claim 8, Naskar teaches that the polymer precursor fibers (which read on the claimed “template structure,”) may be formed from a polyolefin ([0044]).
Regarding claim 9, Naskar teaches that precursor fibers are converted into carbon fibers during the inventive process (Abstract); thus, the fiber-like structure is retained during the conversion (carbonization) process, which reads on the claimed limitation wherein the “carbonized materials retain a shape and structure of the template material.”
Regarding claim 10, Naskar teaches that the inventive process is directed towards fiber structures (Abstract), which reads on the claimed list.
Regarding claim 11, Naskar teaches that the inventive process is directed towards fiber structures (Abstract), which reads on the claimed “structure.” Further, as described in the rejection of claim 5 above, Naskar teaches the formation of carbonized materials which have the same structure as claimed.
Naskar teaches that the inventive carbonized carbon fiber has a surface area ranging from 5 to 3,000 m2/g ([0029]), which encompasses the claimed range of “greater than 200 m2/g,” establishing a prima facie case of obviousness. Naskar differs from claim 11 because it is silent with regard to the claimed average pore volumes.
However, Naskar teaches that the surface area is strongly dependent on the level of porosity of the carbon fibers ([0029]). Naskar further teaches that the carbonized carbon fibers may be microporous, mesoporous, or microporous ([0025]), and teaches that mesopores may range from 2-50 nm in diameter ([0026]). These diameters correspond to a similar range expressed in the instant Specification as capable of producing the claimed “average pore volume” (c.f. Figure 19 of the instant Specification, which shows a distribution of pore widths in nm which roughly corresponds to the same range of mesopore sizes taught by Naskar). Naskar recognizes the pore size of a carbon fiber as a result-effective variable in tuning the surface area of said carbon fiber. Additionally, as expressed above, Naskar teaches a range of surface areas which encompasses (and therefore, surpasses) the maximum surface area required by claim 11. It would therefore be obvious to one of ordinary skill in the art to perform routine optimization on the level of porosity of the carbon fiber for the purpose of achieving the range of surface areas taught by Naskar. The ranges of surface areas and pore volumes taught by Naskar, respectively, encompass and align with those of the instant claim set and Specification. Thus, It would be obvious for one of ordinary skill in the art to reach the claimed ranges of pore volumes within the teachings of Naskar.
Regarding claim 12, Naskar teaches that an element other than carbon may be added to the inventive fibers in dopant amounts, including sulfur ([0023]).
Regarding claim 13, Naskar teaches that the inventive carbonization method may apply to a tow of carbon fiber ([0023]), which reads on the claimed “structure including a plurality of fibers.”
Regarding claim 14, Naskar teaches that the inventive carbonized carbon fiber has a surface area ranging from 5 to 3,000 m2/g ([0029]), which overlaps and anticipates the claimed range of “greater than about 600 m2/g.” Furthermore, as described above, the carbon fiber structure taught by Naskar is produced from the same polymers, via a substantially similar process, resulting in a product with the same surface area and porosity characteristics contemplated by the entirety of the instant specification. Finally, the instant Specification provides no controlling definition of “activated,” but does teach the activation of a carbonized product by reacting said product with potassium hydroxide to enhance porosity and surface area (see instant Specification at [00116]). Therefore, since the teachings of Naskar result in a substantially porous and high surface area product, which reaches all of the claimed surface area and pore volume limitations, the product of Naskar reads on the claimed “activated carbonized materials.”
Regarding claim 15, Naskar teaches that the inventive carbon fiber may possess a thermal conductivity ranging from 0.1 to 2500 W/m-K ([0021]), which encompasses the claimed approximate value of “about 150 W/mk) establishing a prima facie case of obviousness.
Regarding claim 16, Naskar is silent with regard to the claimed “CO-2 sorption capacity.” Nevertheless, Naskar as applied above results in a carbon fiber that is structurally identical to the claimed “carbonized materials,” which contains all of the same components, produced by a substantially identical process, and resulting in a product with anticipatory physical properties including surface area, porosity, and thermal conductivity. Products of identical chemical compositions cannot have mutually exclusive properties. Where the claimed and prior art products are identical or substantially identical in structure or composition, a prima facie case of obviousness has been established. See MPEP 2112.01. The claimed “CO2 sorption capacity” will therefore necessarily be present in Naskar as applied to claim 11, above.
Regarding claim 17, as described above, Naskar teaches that the carbonized fibers may be formed from polyolefins such as polyethylene and polypropylene ([0044]).
Regarding claim 18, Naskar as modified is silent with regard to the claimed shape retention characteristic; however, as described above, Naskar as modified results in a carbonized product which has been produced via a process which is substantially identical to that of the instant Application. Where the claimed and prior art products have been formed from a substantially identical process, a prima facie case of obviousness has been established. See MPEP 2112.01. The claimed shape retention characteristic will therefore necessarily be present in Naskar as modified and as applied above.
Regarding claim 19, Naskar specifically teaches the use of a fiber precursor (Abstract).
Regarding claims 20-22, Naskar teaches that the carbon fibers are generally produced from organic precursors by extrusion and filament generation followed by carbonization, etc. ([0054]). The fiber precursor or Naskar is therefore extruded, and therefore reads on the claimed “extruded structure.”
Response to Arguments
Applicant's arguments filed June 12, 2026 have been fully considered but they are not persuasive.
Applicant argues that Xue differs from claim 2 because it does not contemplate the use of a resol coating. However, the rejection of claim 2 is formed from the combination of Xue with Naskar as opposed to Xue alone. 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).
Applicant further argues that “Neither Naskar nor Xue disclose or provide motivation for one of ordinary skill in the art to perform submersion, evaporation, and cross-linking disclosed by Applicant to arrive at the structure of claim 2.” However, as described above, Xue specifically points out a process involving coating, which prima facie will be equivalent to submersion given the indication that the scaffold is completely coated (including coating on inside structures, see p. 245 scheme 1), solvent evaporation, and thermopolymerization/calcination a temperature and time which fall within the values stipulated within the instant Specification. Therefore, it would have been obvious to one having ordinary skill in the art at the time of filing to perform such steps, and prima facie the same crosslinking characteristic would be afforded during such a step because the processes are substantially identical, having the same time and temperature parameters.
Applicant continues to argue that the prior art documents, Naskar and Soehngen, fail to fully describe the process disclosed by the present application, asserting that “the structure of claim 5 is the result not just of the sulfonation step, but also olefination and subsequent addition/rearrangement.” Applicant additionally stipulates that de-sulfonation, secondary addition, rearrangement, and dissociation are not detailed by Naskar or Soehngen.
However as described previously, the secondary addition, rearrangement, and dissociation steps are specifically indicated in the instant Specification as part of the sulfonation process (c.f. [0070] of the instant Specification, where these steps are indicated as occurring during sulfonation, and [0068], where support for simultaneous sulfonation and crosslinking is supported). The stipulated steps of “de-sulfonation, secondary addition, rearrangement, and dissociation” are therefore capable of being performed during the sulfonation process occurring within the prior art, regardless of whether or not the prior art details these steps. As described above, the prior art describes a sulfonation process which is substantially identical to that which is described within the instant Specification.
Additionally, the instant Specification specifically refers to a purportedly-inventive example which merely includes the submersion of an initial structure into neat sulfuric acid at 155°C, which effects the sulfonation and subsequent crosslinking thereof ([0082]). The applicant appears to have additionally validated the formation of both double bonds and sulfonate groups during the sulfonation reaction via FTIR analysis conducted on purportedly inventive example 3 ([0092]).
As described above, the prior art teaches a sulfonation process which is substantially identical to the one contemplated by the instant Application. Where the claimed and prior art products have been formed from a substantially identical process, a prima facie case of obviousness has been established. See MPEP 2112.01. The pre-carbonized crosslinked structure implied by the claimed structure resulting from sulfonation will therefore necessarily be present in the prior art, as applied above.
Conclusion
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/JOSHUA CALEB BLEDSOE/Examiner, Art Unit 1762
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