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 .
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 33-37 and 39 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Regarding claim 33, the limitation “wherein the ceramic particles distributed throughout the matrix form a chemically linked particle network” appears to be new matter unsupported by the written description as originally filed. Examiner notes [0024] of the PGPub of the instant specification recites “pre-ceramic precursor resin consisting of … novel functionalized ceramic nanoparticles … the particles have functional groups that can form chemically linked particle networks with functional groups on other particles or with the resin matrix.”. Examiner notes this chemically linked particle network referenced in [0024] concerns a resin containing precursor, and claim 1 from which claim 33 depends is a finished ceramic matrix composite which has already undergone pyrolysis to remove all resin and functional groups. As such, the ceramic matrix composite of claim 1 lacks written description support for this new limitation.
Regarding claim 34, the limitation “wherein the ceramic particles are directly bonded to the matrix” appears to be new matter unsupported by the written description as originally filed. The term “directly bonded” does not appear to be present in the original written description, nor does the written description appear to describe or provide support for “the ceramic particles are directly bonded to the matrix”.
Regarding claim 35, the limitation “wherein the ceramic particles distributed throughout the matrix form a chemically linked particle network comprising the ceramic particles chemically linked to one another” appears to be new matter unsupported by the written description as originally filed. As noted in the rejection of claim 33 above, the only support for a chemically linked particle network appears to be [0024] of the instant PGPub which is in reference to a resin containing precursor, not the finished ceramic matrix composite of claim 1. Examiner notes this new matter rejection is similar to the new matter rejection from the non-final rejection dated 11/09/2023.
Regarding claim 36, the limitation “wherein the ceramic particles distributed throughout the matrix form the chemically linked particle network with functional groups on other particles and with the matrix” appears to be new matter unsupported by the written description as originally filed. As similarly noted in the previous final rejection dated 02/28/2024, claim 1 is directed towards the ultimate structure, not the pre-ceramic precursor which contains functional groups. The pyrolization of the pre-ceramic precursor removes all functional groups, and therefore the written description lack support for a ceramic matrix composite final product of claim 1 which contains functionalized ceramic particles.
Regarding claim 37, the limitation “an absence of excess free silicon material” appears to be new matter unsupported by the written description as originally filed. The only reference to an absence of excess free silicon appears to be [0014] of the instant PGPub, which is part of the background of the instant specification and provides a survey of the state-of-the-art. The written description as originally filed does not appear to provide support for the ceramic matrix composite of claim 1 having an absence of excess free silicon.
Regarding claim 39, the limitation “wherein the ceramic matrix composite is corrosion resistant to molten salt at a temperate greater than 700 °C” appears to be new matter unsupported by the written description as originally filed. The only reference to corrosion resistance as well as molten salts with greater than 700°C appears to be [0014] of the instant PGPub, which is part of the background of the instant specification and provides a survey of the state-of-the-art. The written description as originally filed does not appear to provide support for the ceramic matrix composite of claim 1 having corrosion resistant to molten salt at a temperate greater than 700 °C.
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 37 and 39 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 applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Regarding claim 37, The term “an absence of excess free silicon material” in claim 37 is a relative term which renders the claim indefinite. The term “absence of excess silicon” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. For example, is 5% silicon excess silicon, or is 30% silicon required to be excess silicon? A person having ordinary skill in the arts would not reasonably know the boundaries without a clear definition of excess silicon. For the purposes of examination, excess silicone will be interpreted as meaning all silicon is present as free silicon unless otherwise clarified by Applicant during the course of prosecution.
Regarding claim 39, the term “corrosion resistant to molten salt at a temperature greater than 700°C” is unclear. The term corrosion resistant could mean that the material undergoes absolutely no corrosion over any timeframe, or instead could mean a corrosion rate of approximately 730 µm per year as noted by [0013] of the instant specification PGPub. For the purposes of examination, corrosion resistance will be interpreted as meaning any resistance to corrosion to molten salts at a temperature greater than 700°C unless otherwise clarified by Applicant during the course of prosecution.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claim(s) 1, 4-7, 29-30, 32-35 and 37-39 is/are rejected under 35 U.S.C. 103 as being unpatentable over Papenburg et al. (US5565052, hereinafter referred to as Papenburg).
Regarding claim 1, Papenburg discloses a ceramic matrix composite (see Papenburg at the Abstract, disclosing a CMC. Examiner notes CMC stands for ceramic matrix composite), comprising: carbon fibers (see Papenburg at Col. 6, lines 6-7 disclosing carbon fibers); a ceramic matrix directly bonded to the fibers (see Papenburg at Col. 8, lines 45-46, disclosing silicon carbide and silicon in the matrix. Examiner notes silicon carbide is a ceramic per instant claim 32), and ceramic particles (see Papenburg at Col. 14 at lines 12-14 disclosing molten silicon rises within the blank by capillary action, filling its pores almost entirely with silicon. When the temperature is raised further, to about 1750°C-1800°C, some of the metallic silicon is converted to silicon carbide by combination with pyrolytic carbon. Examiner notes this corresponds to SiC particles, which is a ceramic per instant claim 32), distributed throughout the matrix having a particle loading of 30 vol% to 70 vol% (See Papenburg at Col. 13, line 60-61, disclosing a porosity of about 70 vol.%. See also Papenburg at Col. 14 at lines 12-14, disclosing the pores are almost entirely filled with silicon which is at least partially converted to silicon carbide. Examiner notes this would correspond to a SiC particle content of up to 70 vol%, which overlaps with the claimed range.) In the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists (see MPEP 2144.05), wherein the ceramic matrix composite has a porosity of less than 15% vol (see Papenburg at Col. 14 at lines 12-14 disclosing the pores are almost entirely filled with silicon, which corresponds to a porosity of approximately 0%).
Regarding claim 4, Papenburg discloses the ceramic particles are at least one of the group consisting of: silicon carbide (SiC), titanium carbide (TiC), zirconium carbide (ZrC), chromium carbide (Cr2C3), carbon black, inorganic oxides, nitrile- based materials, titanium nitride (TiN), boron nitride (BN), silicon nitride (Si3N4), beryllium oxide (BeO), magnesium oxide (MgO), aluminum oxide (Al2O3), zirconium oxide (ZrO2), samarium oxide (Sm2O3), thorium oxide (ThO3), magnesium aluminum oxide (MgAl2O4), and molybdenum disilicide (see Papenburg at Col. 14 at lines 12-14 disclosing molten silicon rises within the blank by capillary action, filling its pores almost entirely with silicon. When the temperature is raised further, to about 1750°C-1800°C, some of the metallic silicon is converted to silicon carbide by combination with pyrolytic carbon. Examiner notes this corresponds to SiC particles, which is a ceramic per instant claim 32).
Regarding claim 5, Papenburg discloses the ceramic particles have a melting or decomposing temperature equal to or is higher than 1000 °C (See the rejection of claims 1 and 4 above, showing Papenburg discloses SiC as the ceramic. Examiner notes SiC inherently possesses the claimed melting or decomposing temperature equal to or is higher than 1000 °C as noted in [0025] of the instant specification). Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established (see MPEP 2112.01(I) first paragraph), and does not react with molten salt, nitrile, chloride, or fluoride salt (SiC inherently possesses the claimed non-reaction with molten salt, nitrile, chloride, or fluoride salt per [0014] of the instant specification).
Regarding claim 6, Papenburg discloses the fibers are coated (see Papenburg at claim 1, claiming coating the substrate element with a first silicon coating).
Regarding claim 7, Papenburg discloses the matrix and the particles are made of a same material (see the rejection of claim 1, disclosing the matrix of Papenburg corresponds to SiC, and the ceramic particles correspond to SiC).
Regarding claim 29, Papenburg discloses the ceramic matrix composite has a porosity of less than 12% vol (see Papenburg at Col. 14 at lines 12-14 disclosing the pores are almost entirely filled with silicon, which corresponds to a porosity of approximately 0%).
Regarding claim 30, Papenburg discloses the ceramic matrix composite has a porosity of less than 8% vol (see Papenburg at Col. 14 at lines 12-14 disclosing the pores are almost entirely filled with silicon, which corresponds to a porosity of approximately 0%).
Regarding claim 32, Papenburg discloses the ceramic particles are at least one of the group consisting of: silicon carbide (SiC), titanium carbide (TiC), zirconium carbide (ZrC), chromium carbide (Cr2C3), carbon black, nitrile-based materials, titanium nitride (TiN), boron nitride (BN), silicon nitride (Si3N4), and molybdenum disilicide (see Papenburg at Col. 14 at lines 12-14 disclosing molten silicon rises within the blank by capillary action, filling its pores almost entirely with silicon. When the temperature is raised further, to about 1750°C-1800°C, some of the metallic silicon is converted to silicon carbide by combination with pyrolytic carbon. Examiner notes this corresponds to SiC particles, which is a ceramic per instant claim 32).
Regarding claim 33, Papenburg discloses wherein the ceramic particles distributed throughout the matrix form a chemically linked particle network (see Papenburg at Fig. 1, showing the light filled pores within the dark matrix).
Regarding claim 34, Papenburg discloses wherein the ceramic particles are directly bonded to the matrix (see Papenburg at Fig. 1, showing the light particles directly bonded to the matrix).
Regarding claim 35, Papenburg discloses wherein the ceramic particles distributed throughout the matrix form a chemically linked particle network comprising the ceramic particles chemically linked to one another (see Papenburg at Fig. 1, showing the light particles distributed throughout the matrix forming a chemically linked particle network comprising the ceramic particles chemically linked to one another).
Regarding claim 37, Papenburg discloses wherein the ceramic matrix composite comprises an absence of excess free silicon material (see Papenburg at Col. 14 at lines 12-14 disclosing molten silicon rises within the blank by capillary action, filling its pores almost entirely with silicon. When the temperature is raised further, to about 1750°C-1800°C, some of the metallic silicon is converted to silicon carbide by combination with pyrolytic carbon. Examiner notes this corresponds to an absence of excess free silicon material).
Regarding claim 38, Papenburg discloses wherein the ceramic particles are distributed throughout the matrix such that the ceramic particles do not agglomerate (see Papenburg at Fig. 1, showing the light particles distributed throughout the matrix such that the ceramic particles do not agglomerate.).
Regarding claim 39, while Papenburg does not explicitly disclose the ceramic matrix composite is corrosion resistant to molten salt at a temperate greater than 700 °C, the corrosion resistance of a ceramic matrix composite is a function of the composition of the ceramic matrix composite as evidenced by the instant specification at [0014] of the PGPub, which states Carbon/Carbon-Silicon Carbide (C/C—SiC) CMCs made by liquid silicon infiltration (LSI) have shown good corrosion resistance to chloride molten salts. Because Papenburg is directed towards a CMC made by liquid silicon infiltration where some silicon is converted to SiC as detailed in the rejections above, it would inherently have the claimed corrosion resistance at a temperature of greater than 700°C. Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established (see MPEP 2112.01(I) first paragraph).
Response to Arguments
Applicants arguments concerning the 112(b) rejections of claims 4 and 32 are convincing and the 112(b) rejections of claims 4 and 32 are withdrawn.
Applicant's arguments filed 01/15/2026 concerning the 103 rejections over Papenburg have been fully considered but they are not persuasive. At the first paragraph of page 6 of the Remarks, Applicant argues that Papenburg does not teach or suggest the ceramic particles are distributed throughout the matrix. Examiner respectfully disagrees, and notes that the ceramic particles are distributed throughout the matrix in the same manner as the previous porosity is distributed. Additionally, the phrase “distributed throughout” does not appear to have any special technical definition; merely being inside of the matrix in multiple places means the particles are distributed throughout. Applicant further argues that Papenburg does not teach or suggest a particle loading of 30 vol% to 70 vol% because Papenburg discloses that only some of the silicon is converted to silicon carbide, and notes that col. 14, lines 19-21 of Papemburg states that 20% of the matrix is composed of unreacted, free metallic silicon. Examiner notes the section referred to in col. 14 of Papenburg corresponds to “Example 2” of Papenburg. Examiner additionally notes that per the rejections above, Papenburg discloses up to 70% porosity, with nearly complete silicon infiltration, and some conversion of silicon to silicon carbide. While Example 2 has 20% of the matrix composed of unreacted, free metallic silicon, this would leave approximately 50% silicon carbide, which is within the claimed range. Examiner notes that even if Example 2 is taken as the upper limit of what Papenburg is capable of achieving, up to 50% silicon carbide is well within the claimed range of 30-70%. Examiner additionally notes that Example 2 is merely one example within the broader teachings of Papenburg, and does not necessarily correspond with the maximum silicon carbide content achieved by Papenburg. As such, these arguments are not convincing.
At pages 6-7 of the Remarks, Applicant argues that Papenburg does not disclose the limitations of newly dependent claims 33-39. Examiner respectfully disagrees for the reasons stated above in the rejections of claims 33-35 and 37-39 above. Examiner further notes the subject matter of claim 36 appears to be new matter unsupported by the written description as originally filed as noted in the rejection of claim 36 under 112(a) above, as well as in the analogous rejection from a similar limitation in the final rejection dated 02/28/2024. As such, Examiner does not find claims 33-39 allowable.
At the second paragraph of page 7 of the Remarks, Applicant argues that Papenburg uses a silicon infiltration method while the instant invention uses a slurry method. Examiner notes this does not appear to be relevant to the instant question of patentability. "The patentability of a product does not depend upon its method of production. If the product in [a] product-by-process claim is the same as or obvious from a product of the prior art, [then] the claim is unpatentable even though the prior [art] product was made by a different process.” In re Thorpe, 227 USPQ 964, 966 (Fed. Cir. 1985) (citations omitted). 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 unobvious difference between the claimed product and the prior art product. In re Marosi, 218 USPQ 289, 292 (Fed. Cir. 1983) (see MPEP 2113(I)).
At the last paragraph of page 7 to the first paragraph of page 8, Applicant argues that the process of Papenburg results in excess free silicon in the CMC. Examiner notes that the phrase “excess free silicon” does not appear to be defined within Papenburg or the instant application. As such, one cannot reasonably determine whether the free silicon of Papenburg is excess without a clear definition of the mathematical boundaries of the term excess.
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 CAMERON K MILLER whose telephone number is (571)272-4616. The examiner can normally be reached M-F 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, Amber Orlando can be reached at (571) 270-3149. 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.
CAMERON K MILLER
Examiner
Art Unit 1731
/CAMERON K MILLER/Examiner, Art Unit 1731