DETAILED ACTION
Response to Amendment
Applicant's amendment filed 4/28/2026 has been entered. Currently, claims 1-9, 11-20 are pending, claim 10 is canceled and claims 8, 9 and 14-20 are withdrawn.
Please note that the text of canceled claims should not be shown, see 37 CFR 1.121(c)(4).
Drawings
The drawings were received on 4/28/2026. These drawings are acceptable.
Claim Rejections - 35 USC § 102
Claims 1-3, 6 and 11-13 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Subramanian et al. (7,942,988).
With regard to claims 1-3, 6, 12 and 13, Subramanian et al. teach a fuel system that includes a flexible fuel that reads on applicants’ printable composite ink and includes porous silicon particles having mean pore sizes in the range of from 4-7 nm, which read on applicants’ plurality of metalloid fuel particles having a plurality of internal pores and being nano-porous, and a polymeric binding material, which reads on applicants’ polymeric binder that is permeable to a desired solvent (col. 3, lines 28-45). The methanol solvent acts as a carrier for carrying the oxidizer into the pores of the silicon particles, which means the composition of Subramanian et al. reads on the functional limitations that the polymeric binder is permeable to methanol (col. 6, lines 43-45). There is no metal oxide present and the particle have a hydrogen terminated surface, which means it will inherently have hydrogen termination on an internal surface of the pores (col. 4, lines 28-31). The flexible fuel may be shaped by melting the polymeric binding material, which means the flexible fuel reads on a printable solid ink, and can be formed without the addition of an oxidizer, which reads on applicants’ inert configuration (col. 5, lines 34-47).
With specific regard to claim 13, there may also be an oxidizer mixed with methanol solvent that acts as a carrier for carrying the oxidizer into the pores of the silicon particles, which with the plastic mass of Example 1 reads on applicants’ kit including oxidizer solution and desired solvent (col. 4, lines 54-65 and col. 6, lines 19-26 and 43-45).
With regard to claim 11, the mixture of Example 1 formed into a plastic mass has a ratio of porous silicon powder to PTFE polymeric binder of 10:1, which would be a weight ratio of approximately 91%:9% (col. 6, lines 18-26).
Claim Rejections - 35 USC § 103
Claim 4 and 5 are rejected under 35 U.S.C. 103 as being unpatentable over Subramanian et al. (7,942,988).
With regard to claim 4, Subramanian et al. teach all of the limitations of claim 1 above. They also teach that the average pore size is from 4-7 nm (col. 3, lines 30-33).
This value overlaps with the range claimed, which means a prima facie case of obviousness exists.
It has been held that “[i]n the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists.” Please see MPEP 2144.05, In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); and In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).
With regard to claim 5, Subramanian et al. teach pore volumes of up to “about 0.5 cc/g”, wherein the term “about” would include amounts slightly above this value (col. 3, lines 30-33). The density of solid silicon in cc/g is approximately 0.429. They also teach that porosity can be adjusted to tailor the reaction rate (col. 5, lines 18-20); however, Subramanian et al. does not specifically teach the porosity claimed.
It would have been obvious to one having ordinary skill in the art to have made the pore volumes slightly higher than 0.5, such as 0.525, as suggested by the reference in order to increase the reaction rate of the fuel. This pore volume would be approximately a porosity of 55%, i.e. = 0.525/(0.525+0.429). One of ordinary skill would understand that a higher porosity would have a higher surface area and would lead to a higher reaction rate.
Potential Allowable Subject Matter
Claim 7 is objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter:
The prior art does not teach or suggest a printable composite ink comprising the metal or metalloid fuel particles each having a plurality of internal pores, a polymeric binder that is permeable to methanol and may, or may not, have an oxidizer present in the fuel, and wherein “each metal or metalloid fuel particle has a diameter of 25 to 100 nm” in combination with the rest of the limitations claimed. Subramanian et al. cannot teach such a particle diameter for each of the fuel particles, and there would no rationale save improper hindsight to have made their particle have the particle diameter claimed.
Response to Arguments
Applicant’s arguments, see Remarks, filed 4/28/2026, with respect to the objection to the drawings, the claim objections, the 112(b) rejections and the prior art rejections over Abe and Zhou have been fully considered and are persuasive. The relevant objections/rejections have been withdrawn.
Applicant's arguments filed 4/28/2026 have been fully considered but they are not persuasive.
Applicants argue on pages 6-7 of their Remarks that the preamble limitations of “printable composite ink” is not taught in Subramanian et al. and applicants are claiming an ink with “fluid properties”.
The Examiner respectfully disagrees and 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., an ink with “fluid properties”) 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). The preamble limitations of “printable composite ink” does not require the ink to be fluid at room temperature or to comprise a solvent.
Additionally, the Examiner is interpreting the limitations of the preamble to be functional limitations of the composition that is recited in the body of the claim. The claims are broad enough that a solid ink that is melted prior to usage would read on a printable composite ink. The fuel of Subramanian et al. can be shaped by heating the fuel such that it is melted and cast into a mold (col. 5, lines 34-38). It is also noted that applicants state at [0041] of their specification that their printable composite ink can be used in a 3D printer. A type of known 3D printer is fused deposition modeling, which uses melted plastic compositions. Given the context in applicants’ specification and the teachings of the prior art, the flexible fuel of Subramanian et al. that can be melted reads on the functional limitations of a “printable composite ink” as claimed.
Applicants argue on pages 9-10 of their Remarks that Subramanian et al. does not render obvious claims 4 and 5 because there is no reason to substitute kerosene with methanol.
The Examiner respectfully disagrees for multiple reasons. First, it is noted that the features upon which applicant relies (i.e., using “methanol as its solvent”) 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). Methanol is not required in the printable composite ink of claims 1, 4 or 5.
Second, the basis of the rejection of claims 4 and 5 has nothing to do with the solvent, and the Examiner never proposed or rendered obvious substituting solvents in Subramanian et al.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to GERARD T HIGGINS whose telephone number is (571)270-3467. The examiner can normally be reached M-F 9:30-6pm.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Mark Ruthkosky can be reached at (571) 272-1291. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/Gerard Higgins/Primary Examiner, Art Unit 1785
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