DETAILED ACTION
The claims 1-20 are pending and presented for the examination.
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 .
Information Disclosure Statement
The information disclosure statements (IDS) submitted on 02/23/2024 and 09/03/2025 are being considered by the examiner.
Claim Rejections - 35 USC § 101
35 U.S.C. 101 reads as follows:
Whoever invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof, may obtain a patent therefor, subject to the conditions and requirements of this title.
Claims 9-16 are rejected under 35 U.S.C. 101 because the claimed invention is directed to an abstract idea without significantly more. Independent claim 9 recites that an “expected anisotropic shrinkage is characterized”, and that an initial model is “elongated”. These concepts of somehow determining what shrinkage is expected, and elongating a model in a manner that is not specified or quantified, are abstract ideas about how the green body should be shaped. This judicial exception is not integrated into a practical application because it is not clear what, if any, model is actually being produced based on the metal concepts of characterizing expected shrinkage and elongating an axial dimension. Because no actual physical or representative model is actual being made by these aforementioned two processes, they are mental exercises only as written in the instant claims. The claim does not include additional elements that are sufficient to amount to significantly more than the judicial exception because the further limitations pertaining to the preparation of the 3D model generation provide no more specificity as to how the aforementioned mental processes are used to carry out physical steps in the claimed process.
Claims 10-16 are also rejected under USC 101 as depending from and thus containing the same limitations as claim 9 from which they depend.
Claim Rejections - 35 USC § 112
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 7, 15, and 19 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.
Claims 7 and 15 recite that the sacrificial powder is densified or sintered during the DCS process, however, it is unclear how this could occur, as a sacrificial powder is by definition removed to form the intended porosity. As such, sintering or densification of the pore-former (sacrificial) powder that would integrate said powder into the ceramic would counteract the functioning of this component. Because of this ambiguity, it is unclear how the further steps of claims 7 and 15 can operate, and the claims are indefinite under USC 112.
Claim 19 is indefinite because the term “tortuous pathway” is ambiguous and it the nature of the intended pore shape/size is unclear from this wording.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claims 1-2, 4, 6-8, 17-18, and 20 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Liu (CN 108191453 A).
Regarding claim 1, Liu teaches a method of forming a porous silicon carbide ceramic comprising the steps of preparing pore-forming agents, preparing a mixture of short fibers and silicon carbide powder and ball milling, mixing the pore-forming agents and powder to form a green body, pressing, and sintering by discharge plasma sintering (see claim 1). The discharge plasma sintering is a direct current sintering process. The pressing step of Liu inherently loads the green body along a first axis, and the elevated sintering temperature is sufficient to sinter the green body. The resultant sintered body then constitutes an intermediate body according to the instant claim, in that it comprises a sintered ceramic material formed from the primary silicon carbide ceramic powder, and further contains the pore-forming agent (sacrificial) powder.
After sintering, the Liu method comprises oxidizing the sintered body. Liu teaches that oxidizing is undertaken “to obtain the porous silicon carbide ceramic material” from the silicon carbide body produced in the sintering step (see example 1). This indicates that this step removes the sacrificial body and leaves voids/pathways in the sintered silicon carbide.
The limitation stating that the green body is elongated relative to a first axis to account for anisotropic shrinkage does not impart any necessarily present shape limitations on the green body. The phrase “elongated relative to a first axis” describes a dimension based on a hypothetical different instance of the axis length. As such, any dimension of the green body axis would be “elongated” depending on which dimension it is being compared to. In the instant claim, there is no specifics as to which dimension the “elongated” dimension is being compared to, and as such any dimension would meet this claim limitation. The limitation that the dimension is to account for shrinkage is based on an intended result from a sintering process, and as the limitation does not quantitatively or relatively specify the dimension, any green body axis would similarly meet the instant claim limitations.
Each limitation of claim 1 is therefore met by Liu, and the claim is anticipated by the prior art of record.
Regarding claim 2, as discussed above, Liu teaches an oxidation process that removes the pore-forming agents to form the inventive porous silicon carbide.
Regarding claim 4, Liu teaches a process for producing a carbide.
Regarding claim 6, Liu teaches that the inventive green body comprises fibers along with the pore-forming agent. These constitute filler material according to the instant claim. The instant claim limitation that the filler is included as a part of the sacrificial powder is met by the Liu method because Liu teaches the mixing together of all components. In this resultant state, the Liu fiber component would be intermixed with the pore-forming agent in a manner that is indistinguishable from the claimed method wherein the sacrificial agent includes a filler material.
Regarding claim 7, Liu teaches sintering by a plasma discharge sintering process, which is a direct current process.
Regarding claim 8, the limitation that the component is “configured” to be install on an aircraft does not impart any necessary structural details on the claimed component. Because the Liu component would be capable of some use as a component of an aircraft (for instance, as a filter component), it is “configured” such that this further limitation of claim 8 is met.
Regarding claim 17, the Liu ceramic component is porous and, as discussed above, is produced by a process that meets each limitation of the instant claim. Any porosity would be able to allow fluid passage to a certain extent, and thus the configurational limitation of the claim is met by the Liu ceramic. Each limitation of the instant product claim is thus taught by Liu, and the claim is anticipated by the prior art of record.
Regarding claim 18, the Liu ceramic is silicon carbide.
Regarding claim 20, the limitation that the component is “configured” to be install on an aircraft does not impart any necessary structural details on the claimed component. Because the Liu component would be capable of some use as a component of an aircraft (for instance, as a filter component), it is “configured” such that this further limitation of claim 8 is met.
Claims 1-2, 4, 8-10, 12, 16-18, and 20 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Wu et al (CN 115536401 A).
Regarding claim 1, Wu et al teaches a method of forming a shaped ceramic component by first forming and printing a mixture of ceramic powder and spherical pore-forming agent PMMA. This constitutes producing a green body through deposition according to the instant claim limitation. Said green body is sintered by spark plasma sintering, which is a direct current sintering method, and said sintering is carried out with mechanical pressure being applied to the mold into which the green body is placed. This pressure is applied along an axis and thus constitutes axial loading. The pore-forming agent component is removed through degreasing, with embodiments taught wherein said degreasing is carried out in an air environment, and is thus an oxidation process. The removal of the pore-forming agent inherently leads voids within the sintered body.
The limitation stating that the green body is elongated relative to a first axis to account for anisotropic shrinkage does not impart any necessarily present shape limitations on the green body. The phrase “elongated relative to a first axis” describes a dimension based on a hypothetical different instance of the axis length. As such, any dimension of the green body axis would be “elongated” depending on which dimension it is being compared to. In the instant claim, there is no specifics as to which dimension the “elongated” dimension is being compared to, and as such any dimension would meet this claim limitation. The limitation that the dimension is to account for shrinkage is based on an intended result from a sintering process, and as the limitation does not quantitatively or relatively specify the dimension, any green body axis would similarly meet the instant claim limitations.
Therefore, each patentably weighted limitation of the instant claim 1 is met by the Wu et al teachings, and the claim is anticipated by the prior art of record.
Regarding claim 2, Wu et al teaches pore-forming agent removal by a degreasing process carried out in air, and thus an oxidation process.
Regarding claim 4, Wu et al teaches that the ceramic powder component is silicon nitride.
Regarding claim 8, Wu et al teaches that the inventive ceramic components are used in aerospace applications, and thus as a component of an aircraft. Further, the limitation that the component is “configured” to be install on an aircraft does not impart any necessary structural details on the claimed component. Because the Wu et al component would be capable of some use as a component of an aircraft, it is “configured” such that this further limitation of claim 8 is met.
Regarding claim 9, Wu et al teaches a method of forming a shaped ceramic component by modeling the component using software and forming a structure using 3D printing. The material that is printed is a mixture of ceramic powder and spherical pore-forming agent PMMA. This constitutes producing a green body through deposition according to the instant claim limitation. Said green body is sintered by spark plasma sintering, which is a direct current sintering method, and said sintering is carried out with mechanical pressure being applied to the mold into which the green body is placed. This pressure is applied along an axis and thus constitutes axial loading. The pore-forming agent component is removed through degreasing, with embodiments taught wherein said degreasing is carried out in an air environment, and is thus an oxidation process. The removal of the pore-forming agent inherently leads voids within the sintered body.
The limitations to characterizing an expected anisotropic shrinkage and elongating the 3D model are mental processes and do not lead to any actual physical products or representations being formed. As such, they cannot hold patentable weight in distinguishing the claimed method over a prior art method meeting each limitation of the instant claim but not stating that these characterizing and elongating steps are carried out. Wu et al provides such a teaching, in that each process limitation of the instant claim that represents a physical step is met by the Wu et al method. Therefore, each patentably weighted limitation of the instant claim 9 is met by the Wu et al teachings, and the claim is anticipated by the prior art of record.
Regarding claim 10, Wu et al teaches pore-forming agent removal by a degreasing process carried out in air, and thus an oxidation process.
Regarding claim 12, Wu et al teaches that the ceramic powder component is silicon nitride.
Regarding claim 16, Wu et al teaches that the inventive ceramic components are used in aerospace applications, and thus as a component of an aircraft. Further, the limitation that the component is “configured” to be install on an aircraft does not impart any necessary structural details on the claimed component. Because the Wu et al component would be capable of some use as a component of an aircraft, it is “configured” such that this further limitation of claim 16 is met.
Regarding claim 17, the Wu et al ceramic component is porous and, as discussed above, is produced by a process that meets each limitation of the instant claim. Any porosity would be able to allow fluid passage to a certain extent, and thus the configurational limitation of the claim is met by the Wu et al ceramic. Each limitation of the instant product claim is thus taught by Wu et al, and the claim is anticipated by the prior art of record.
Regarding claim 18, Wu et al teaches a silicon nitride ceramic.
Regarding claim 20, Wu et al teaches that the inventive ceramic components are used in aerospace applications, and thus as a component of an aircraft. Further, the limitation that the component is “configured” to be install on an aircraft does not impart any necessary structural details on the claimed component. Because the Wu et al component would be capable of some use as a component of an aircraft, it is “configured” such that this further limitation of claim 20 is met.
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.
Claims 5 and 13 are rejected under 35 U.S.C. 103 as being unpatentable over Wu et al (CN 115536401 A) in view of Gong et al (CN 107573080 A).
Regarding claim 5, the claim differs from Wu et al as applied above because Wu et al does not teach that the pore-former is graphite. However, it would have been obvious to one of ordinary skill in the art to modify Wu et al in view of Gong et al in order to use such a graphite pore-former. Gong et al teaches a porous silicon nitride ceramic component prepared by adding a pore-former to a starting ceramic powder, uniaxial pressing of the green body, and sintering. Gong et al teaches that the pore-forming agent can be selected as graphite from a list of four materials that includes PMMA. This teaching would indicate to one of ordinary skill in the art that the selection of graphite or PMMA as the pore-forming agent would be a matter of using equivalent components to produce equivalent and expected porosity results. As such, the choice by a skilled artisan of graphite as pore-former could be made by such factors as material cost and availability. Because Wu et al and Gong et al each teach porous silicon nitride ceramics made by similar methods, one would have had a reasonable expectation of success in the modification. Each limitation of claim 5 is therefore met by the teachings of the prior art of record, and the claim is obvious and not patentably distinct.
Regarding claim 13, the claim differs from Wu et al as applied above because Wu et al does not teach that the pore-former is graphite. However, it would have been obvious to one of ordinary skill in the art to modify Wu et al in view of Gong et al in order to use such a graphite pore-former. Gong et al teaches a porous silicon nitride ceramic component prepared by adding a pore-former to a starting ceramic powder, uniaxial pressing of the green body, and sintering. Gong et al teaches that the pore-forming agent can be selected as graphite from a list of four materials that includes PMMA. This teaching would indicate to one of ordinary skill in the art that the selection of graphite or PMMA as the pore-forming agent would be a matter of using equivalent components to produce equivalent and expected porosity results. As such, the choice by a skilled artisan of graphite as pore-former could be made by such factors as material cost and availability. Because Wu et al and Gong et al each teach porous silicon nitride ceramics made by similar methods, one would have had a reasonable expectation of success in the modification. Each limitation of claim 13 is therefore met by the teachings of the prior art of record, and the claim is obvious and not patentably distinct.
Conclusion
14. No claim is allowed.
15. The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
16. Any inquiry concerning this communication or earlier communications from the examiner should be directed to NOAH S WIESE whose telephone number is (571)270-3596. The examiner can normally be reached on Monday-Friday, 7:30am-4:30pm.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Amber Orlando can be reached on 571-270-3149. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/NOAH S WIESE/Primary Examiner, Art Unit 1731
NSW5 June 2026
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