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 .
Response to Amendment
The amendment dated 5/29/2026 has been considered and entered into the record. Claims 1–19 remain pending, while claims 8–19 are withdrawn from consideration. Claims 1–7 are examined below.
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) 1–6 are rejected under 35 U.S.C. 103 as being unpatentable over Maki (WO 2019/065535 A1) in view of Watanabe (US 2005/0170169 A1).
Maki teaches the formation of a prepreg composite material, wherein the material comprises a plurality of carbon nanotubes 14a that are directly attached to the surface of carbon fibers 12a in the form of a network. Maki abstract, Description of Embodiments. The nanotubes are attached to the surface of the carbon fibers using polymeric resin sizing agent 16a. Id. Description of Embodiments, Fig. 4. The mass of the sizing agent relative to the carbon fibers ranges from about 0.4 to 3 percent. Id. The carbon fibers and nanotubes are covered by a matrix resin layer 20 (second sizing agent) in a composite resin layer 18. Id. Description of Embodiments, Figs. 5, 7. The matrix resin layer 20 may comprise polymers such as epoxy and polyolefin resins. Id. Description of Embodiments. The Examiner notes that while the nanotubes are not described as having a “bent shape with a bent portion,” the nanotubes of Maki appear to have the required bent shape and bent portion based upon illustrations and pictures. See id. Figs. 7–9.
Maki fails to teach that the nanotubes form a network structure, wherein the nanotubes are sized and crosslinked together by a carbodiimide-derived structure and a functional group of the carbon nanotubes.
Watanabe teaches the formation of a nanotube structure and polymer composite in which the structure is formed by cross-linking functional groups bonded to multiple carbon nanotubes via chemical bonding of the functional groups. Watanabe abstract. The nanotubes within the structure 1 have a bent structure with bent portions and are in direct contact with each other, wherein cross-linked sites 12 connect functional groups bonded to the carbon nanotubes. Id. ¶ 67, Fig. 1. The cross-linked sites are formed using a first sizing agent such as polycarbodiimide and the carbon nanotube functional groups. Id. ¶¶ 26–27. The Examiner takes the position that because the polycarbodiimide is a carbodiimide-derived structure that reacts with functional groups of the carbon nanotube to cross-link the nanotubes it constitutes a “sizing agent” because it performs the claimed function and has the claimed composition of a “sizing agent.”
It would have been obvious to one of ordinary skill in the art to have replaced the nanotubes of Maki with the bent nanotube structure of Watanabe, wherein the nanotubes within the structure are in direct contact and are cross-linked to each other using carbodiimide to the carbon fibers in the Maki prepreg motivated by the desire to further reinforce the prepreg material using the entangled nanotube structure of Watanabe due to the cross-linked nanotube network structure.
Claim 6 is rejected as it would have been obvious to have selected a water-soluble polymer for the matrix resin layer 20 that creates a composite resin layer 18 and that covers the nanotube structure because as a solvent “water solvent is preferable in terms of handleability and safety.” Maki Description of Embodiments.
Claim(s) 7 is rejected under 35 U.S.C. 103 as being unpatentable over Maki and Watanabe as applied to claim 6 above, and further in view of Tomioka (US 2015/004470 A1).
Maki and Watanabe fail to teach the use of polyvinyl alcohol as a protection agent that adheres to the surface of the nanotube structure to cover the surface of the structure.
Tomioka teaches the creation of a carbon fiber resin prepreg, wherein the prepreg is obtained by covering the carbon fibers with resins such as polyolefin and polyvinyl alcohol resins. Tomioka ¶ 97.
It would have been obvious to one having ordinary skill in the art at the time the invention was made to substitute the polyolefin resin of Maki with polyvinyl alcohol because Tomioka teaches the functional equivalency of the two polymers for use in carbon fiber prepregs. Simple substitution of one known element for another to obtain predictable results is obvious. KSR International Co. v. Teleflex Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007).
Response to Arguments
Applicant's arguments filed 5/19/2026 have been fully considered but they are not persuasive.
Applicant argues that the nanotubes of Watanabe are not in direct contact with one another, but are instead separated by cross-linked sites. Applicant further contends that the residual cross-linking material prevents the carbon nanotubes from actually making direct contact with one another. These arguments are unpersuasive. Watanabe expressly teaches that the “carbon nanotubes are substantially in direct contact with each other.” Watanabe ¶ 149 (emphasis added). Accordingly, Applicant’s argument is unpersuasive because the nanotubes of Watanabe are in direct contact with each other.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MATTHEW D MATZEK whose telephone number is (571)272-5732. The examiner can normally be reached M-F 9:30-6.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Jennifer Boyd can be reached at 571.272.7783. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/MATTHEW D MATZEK/Primary Examiner, Art Unit 1786
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