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 .
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Information Disclosure Statement
The information disclosure statement(s) (IDS) submitted on 8/29/24 and 6/5/25 have been considered by the examiner.
Election/Restrictions
Applicant’s election of claims 5-7 in the reply filed on 7/16/26 is acknowledged. Because applicant did not distinctly and specifically point out the supposed errors in the restriction requirement, the election has been treated as an election without traverse (MPEP § 818.01(a)).
Claims 1-4 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected group, there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 7/16/26.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
Language from the reference(s) is shown in quotations. Limitations from the claims are shown in quotations within parentheses. Examiner explanations are shown in italics.
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.
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 set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied 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.
Claims 5-7 are rejected under 35 U.S.C. 103 as being unpatentable over Spitsberg et al. (US 20060210800 A1), previously cited, in view of Hinoki et al. US 20200071236 A1).
Regarding claims 5-6, Spitsberg teaches “a process for reacting a metal source and a silica source over the silicon carbide and/or silicon metal alloy-containing substrate to form a relatively thin environmental barrier layer comprising the reaction-generated corrosion resistant metal silicate” (which reads upon “a method for producing silicon carbide ceramics comprising a silicon carbide ceramic substrate and a coating layer coating a surface of the silicon carbide ceramic substrate, the method comprising”, as recited in the instant claim; paragraph [0002]). Spitsberg teaches “(a) providing a silicon carbide and/or silicon metal alloy-containing substrate” (paragraph [0014]). Spitsberg teaches “(b) reacting a metal source and a silica source to form over the substrate an environmental barrier layer comprising a reaction-generated corrosion resistant metal silicate” (which reads upon “(C) applying a coating layer precursor containing a metal oxide onto a surface of a sintered product obtained in step (B) and then heat-treating the sintered product and the coating layer precursor”, as recited in the instant claim; paragraph [0015]). Spitsberg teaches that “the corrosion resistant metal silicate of this invention is formed as a reaction product between a metal source (e.g., a metal oxide, metal nitrate, metal chloride, etc.) and a silica source” (which reads upon “containing a metal oxide”, as recited in the instant claim; paragraph [0020]). Spitsberg teaches that “EBL 58 is prepared by reacting a metal source (e.g., a metal oxide such as yttria, a metal nitrate, a metal halide, such as a metal chloride, metal fluoride, metal bromide, etc.) with a silica source” (which reads upon “yttrium oxide (Y203)”, as recited in instant claim 6; paragraph [0036]; yttria is yttrium oxide (Y203)). Spitsberg teaches “a process for reacting a metal source and a silica source over the silicon carbide and/or silicon metal alloy-containing substrate to form a relatively thin environmental barrier layer comprising the reaction-generated corrosion resistant metal silicate” (which reads upon “heat-treating the sintered product and the coating layer precursor at a temperature equal to or higher than a eutectic temperature between silicon dioxide derived from the sintered product, the metal oxide derived from the sintered product, and the metal oxide derived from the coating layer precursor to convert the coating layer precursor to a coating layer containing a silicate”, as recited in the instant claim; paragraph [0002]; one of ordinary skill in the art would understand that in order to obtain the reaction-generated corrosion resistant metal silicate, the reactants must be heated to a temperature equal to or higher than a eutectic temperature, because at a temperature equal to or higher than a eutectic temperature, the eutectic liquid lowers the activation energy for ion transport, enabling rapid silicate formation; additionally, a eutectic temperature between Y₂O₃–SiO₂ is about 1100 °C).
Additionally, or alternatively, Spitsberg is silent regarding the temperature of the reaction step.
Regarding the subject limitation, in order to carry out the method of Spitsberg, it would have been necessary and obvious to look to the prior art for exemplary temperatures used in reacting a metal source and a silica source to form a corrosion resistant metal silicate. Hinoki provides this teaching. Hinoki is similarly concerned with providing SiC ceramics having excellent environmentally resistant coating (paragraph [0009]). Hinoki teaches “(3) a step of heat-treating the sintered product obtained in step (2) to form a surface modification layer containing a silicate on a silicon carbide ceramics” (paragraph [0027]). Hinoki teaches “the silica (SiO2) reacts with the metal oxide (such as Yb2O3) contained in the matrix; as a result, a surface modification layer of silicate (such as Yb2SiO5, Yb2Si2O7, or the like) is formed in the vicinity of the ceramics surface” (paragraph [0049]). Hinoki teaches “the silicate preferably has excellent heat resistance and environmental resistance” (paragraph [0056]). Hinoki teaches “an oxidation heat treatment, which is performed after a dispersion step and a sintering step” (which reads upon “heat-treating the sintered product”, as recited in the instant claim; paragraph [0049]). Hinoki teaches that “the temperature during the heat treatment is preferably about 800 to 1700° C., more preferably about 1100 to 1500° C” (which reads upon “at a temperature equal to or higher than a eutectic temperature between silicon dioxide derived from the sintered product, the metal oxide derived from the sintered product, and the metal oxide derived from the coating layer precursor to convert the coating layer precursor to a coating layer containing a silicate”, as recited in the instant claim; paragraph [0079]; a eutectic temperature between Y₂O₃–SiO₂ is about 1100 °C). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to form the silicate of the prior art combination, and adjusting and varying the temperature, such as within the claimed ranges, as taught by Hinoki, motivated to form a conventional corrosion resistant metal silicate using known and tested reaction temperatures predictably suitable for reacting a metal source and a silica source to form a corrosion resistant metal silicate.
Spitsberg teaches “(a) providing a silicon carbide and/or silicon metal alloy-containing substrate” (paragraph [0013]). Spitsberg teaches that “the environmental barrier layer of this invention is useful with silicon carbide and/or silicon metal alloy-containing substrates used in a wide variety of turbine engine (e.g., gas turbine engine) parts and components operated at, or exposed to, high temperatures, especially higher temperatures that occur during normal engine operation” (paragraph [0032]).
Spitsberg is silent regarding how the substrate is made. Spitsberg is silent regarding (A) dispersing at least a silicon carbide-forming raw material and a metal oxide in a dispersion medium and (B) sintering a dispersion product obtained in step (A).
Hinoki is similarly concerned with providing SiC ceramics having excellent environmentally resistant coating (paragraph [0009]). Hinoki teaches “(1) a step of dispersing a raw material for forming silicon carbide, and a metal oxide in a dispersion medium” (which reads upon “(A) dispersing at least a silicon carbide-forming raw material and a metal oxide in a dispersion medium”, as recited in the instant claim; paragraph [0025]). Hinoki teaches “(2) a step of sintering the dispersion product obtained in step (1)” (which reads upon “(B) sintering a dispersion product obtained in step (A)”, as recited in the instant claim; paragraph [0026]). Hinoki teaches “wherein the metal oxide is at least one oxide selected from the group consisting of scandium oxide (Sc2O3), yttrium oxide (Y2O3), erbium oxide (Er2O3), ytterbium oxide (Yb2O3), alumina (Al2O3), and lutetium oxide (Lu2O3)” (which reads upon instant claim 6; paragraph [0033]).
Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the method of Spitsberg to include forming the substrate by (A) dispersing at least a silicon carbide-forming raw material and a metal oxide in a dispersion medium;(B) sintering a dispersion product obtained in step (A), as taught by Hinoki because Spitsberg is silent as to how the substrate is made and Hinoki provides this teaching. The rationale to support a conclusion that the claim would have been obvious is that all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination yielded nothing more than predictable results to one of ordinary skill in the art (MPEP § 2143.A.).
Regarding claim 7, modified Spitsberg teaches the method of claim 1 as stated above. Spitsberg teaches that “the reaction between the metal source and the silica source is typically carried out under conditions that allow for the formation of an EBL 58 that is relatively thin, i.e., up to a thickness of about 5 mils (127 microns), and that typically, EBL 58 is formed to have a thickness of from about 0.5 to about 5 mils (from about 13 to about 127 microns), more typically from about 1 to about 2.5 mils (from about 25 to about 64 microns)” (paragraph [0036]).
Contact Information
Any inquiry concerning this communication or earlier communications from the examiner should be directed to REBECCA JANSSEN whose telephone number is (571)272-5434. The examiner can normally be reached on Mon-Thurs 10-7 and alternating Fri 10-6.
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. The Examiner requests that interviews not be scheduled during the last week of each fiscal quarter or the last half of September, which is the end of the fiscal year. Q4: 9/21-9/30/26; Q1: 1/4-1/8/27.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Keith Hendricks can be reached on (571)272-1401. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/REBECCA JANSSEN/Primary Examiner, Art Unit 1733
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