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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 08/13/2026 has been entered.
Allowable Subject Matter
Claims 7-11, 14-15, 19 and 21-24 are allowed.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1-2 and 5-6 are rejected under 35 U.S.C. 103 as being unpatentable over Keith (EP 3042763) in view of Fletcher et al. (PG Pub. 2010/0304041).
Regarding claim 1, Keith teaches a ceramic matrix composite sandwich comprising a ceramic honeycomb core [Title, 0022 and Fig. 2] having oppositely disposed first and second surfaces [Fig. 7]. A first facesheet (16) is taught on the first surface of the honeycomb ceramic core structure and a second facesheet (14) is taught on the second surface of the honeycomb ceramic core structure [Fig, 2]. Keith teaches an interface sheet disposed between the ceramic honeycomb structure and at least one of the first facesheet and the second facesheet as Keith teaches first and second facesheets can be made of one or more prepreg layers wherein one prepreg layer can be construed as the interface layer and the other can be construed as the first or second facesheet [0014]. [0007]. The first facesheet or the second facesheet comprise a ceramic matrix composite [0005]. The interface layer comprises chopped ceramic fibers (short ceramic fibers are taught) [0014]. Keith is silent regarding the interface layer being derived from a paste. However, Fletcher et al. teaches a paste as an interface layer in order to provide one thicker coating layer in less layers without dripping. It would have been obvious to one of ordinary skill in the art to use the paste in the interface layer of Fletcher et al. in Keith in order to provide one thicker coating layer in less layers without dripping and arrive at the claimed invention.
Regarding claim 2, Keith teaches the fibers are oxides ceramics [0017] and the matrix is composed of oxide ceramics [0014] and therefore is an oxide-oxide ceramic material. Paragraph 0022 states “the core 12 may be formed from a CMC having the same or similar chemical composition (i.e., the same filament and matrix composition) as the first facesheet 14 and the second facesheet 16.” and therefore the ceramic honeycomb core structure is also an oxide-oxide ceramic material.
Regarding claim 5, Keith is silent regarding the claimed stabilized compression strength. However, the present claim recites a broad range of stabilized compressive strength and it would have been obvious to one of ordinary skill in the art to arrive at the claimed stabilized compressive strength to improve the strength of the ceramic honeycomb structure core.
Regarding claim 6, the ceramic matrix composite comprises a sintered oxide-oxide ceramic matrix composite [0026].
Claims 3-4 are rejected under 35 U.S.C. 103 as being unpatentable over Keith (EP 3042763) in view of Fletcher et al. (PG Pub. 2010/0304041) in view of Petrisko et al. (US Pat. 5,851,403).
Regarding claims 3-4, The previous combination is silent regarding the claimed nominal cell size and density of the ceramic honeycomb core structure. However, Petrisko et al. teaches ceramic honeycomb core structure with a nominal cell size and density in the claimed range in order to tailor and control mechanical and electrical and chemical properties needed in the end use product. Further, Petrisko et al. teaches the cell size and density as results effective variables that affect the mechanical and electrical and chemical properties. It would have been obvious to one of ordinary skill in the art to arrive at the claimed nominal cell size and density of the ceramic honeycomb structure core in order to tailor the mechanical and electrical and chemical properties to the end use requirements through routine experimentation and arrive at the claimed invention. It would have been obvious to one of ordinary skill in the art to use the nominal cell size and density of the ceramic honeycomb core structure of Petrisko et al. in the previous combination in order to tailor mechanical and electrical and chemical properties and arrive at the claimed invention.
Art Not Cited but Relevant
US Pat. 5,632,834 teaches a sandwich structure with a honeycomb core and facesheets applied to the core.
Response to Arguments
Applicant's arguments filed 08/13/2026 have been fully considered but they are not persuasive. Applicant argues Keith does not teach the claimed paste. However, newly cited Fletcher teaches the claimed paste in the interlayer. Therefore, the present claims are not allowable. Claims 7-11, 14-15, 19 and 21-24 h.ve been found to be allowable.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SHAWN MCKINNON whose telephone number is (571)272-6116. The examiner can normally be reached Monday thru Friday generally 8:00am-5:00pm EST.
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, Marla McConnell can be reached at 571-270-7692. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/Shawn Mckinnon/Examiner, Art Unit 1789
Prosecution Insights