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
Acknowledgment is made of applicant’s claim for foreign priority (EP20202296.8, filed 16 October 2020) under 35 U.S.C. 119 (a)-(d). Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Applicant’s claim for the benefit of a prior-filed application (CON of PCT/IB2021/059493, filed 15 October 2021) under 35 U.S.C. 119(e) or under 35 U.S.C. 120, 121, 365(c), or 386(c) is acknowledged.
Response to Amendment
Applicant’s amendments filed 02 June 2026 has been entered. Claims 1 and 4 have been amended; Claim 2 has been canceled; Claims 12-20 have been withdrawn; and new Claims 21-25 have been added. Claims 1 and 3-25 are pending.
Regarding the Claim Objection of Claim 1, Applicant’s amendments are sufficient; this objection has been withdrawn.
Regarding the rejections of Claim(s) 1 and 3-10 under 35 U.S.C. 103 as being unpatentable over OYAMA et al. (US 2005/0172811 A1) in view of ONOZUKA et al. (US 2017/0259214 A1), Applicant’s amendments are insufficient; the rejection of at least independent Claim 1 has been maintained.
Response to Arguments
Applicant's arguments filed 02 June 2026 have been fully considered but they are not persuasive. Regarding “Claim Rejections - 35 USC§ 103” (pg. 7-8) Applicant argues OYAMA is directed to membranes permeable to gas molecules whereas the claimed invention is directed toward liquid filtration; i.e., one of ordinary skill in the art would not consider the disclosure of OYAMA to address liquid filtration (par. spanning pg. 7-8). Applicant further argues “there is no teaching or suggestion in the cited art, alone or in combination, that the layers have a smaller pore size in every subsequent layer of the multilayer ceramic filtration element from the ceramic support structure to the at least one intermediate layer to the membrane layer” and further, OYAMA discloses adjacent layers having “a pore size difference that is not in the claimed range” (pg. 8, par. 2); therefore, Applicant argues Claim 1 as amended is patentable (pg. 8, par. 3).
Applicant further argues the cited art do not disclose or render obvious the limitations of new Claims 21-25 (pg. 9, par. 3).
The Examiner respectively disagrees.
Regarding OYAMA being directed to membranes permeable to gas molecules whereas the claimed invention is directed toward liquid filtration, it is noted that the claimed invention is directed to a filtration element, not the means or methods by which the claimed device is used. Furthermore, the added limitation of “[a] multilayered ceramic filtration element for liquid filtration” is merely considered a preamble limitation. No other limitation in the body of the claim references or requires the claimed filtration element be used for liquid filtration. As such, the as-amended “for liquid filtration” limitation is considered an intended use of the invention and has no patentable significance on the claimed invention. If the body of a claim fully and intrinsically sets forth all of the limitations of the claimed invention, and the preamble merely states, for example, the purpose or intended use of the invention, rather than any distinct definition of any of the claimed invention’s limitations, then the preamble is not considered a limitation and is of no significance to claim construction. Pitney Bowes, Inc. v. Hewlett-Packard Co., 182 F.3d 1298, 1305, 51 USPQ2d 1161, 1165 (Fed. Cir. 1999) (MPEP 2111.02 II).
Regarding the argument that the teaching or suggestion that the cited art is deficient in disclosing smaller pore sizes in every subsequent layer, it is initially noted that the added limitation is indefinite as rejected in the subsequent 35 USC 112(b) rejection. However, as argued (pg. 8, par. 2), it is believed that the added limitation is interpreted to require that the multilayered ceramic filtration element includes a decreasing gradient pore size from the ceramic support structure to the membrane layer. The Examiner respectfully disagrees that the cited art is deficient in disclosing such an interpreted limitation. As noted in the subsequent 35 USC 103 rejection, OYAMA certainly discloses a decreasing gradient pore size in the multilayered filters from the support layer to the surface layer (e.g., see cited examples). Further, regarding Applicant’s argument that the cited art fails to disclose “a pore size difference” within the claimed range, no such claimed “pore size difference” range is recited. 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).
Finally, regarding the limitations of the new Claims 21-25, the Examiner agrees with Applicant’s assertion that these limitations are not disclosed or made obvious by the cited art.
Claim Interpretation
The claims recite “Z-ratio” and the related terms “D90” and “D10”. As defined in the Specification p0034: “the Z-[ratio] of layer x, i.e., Zx, is the quotient of the particle size D90 of the particles composing the layer and the particle size D10 of the same particles composing the layer”. Further, the terms “D90” and “D10” or more broadly, “Dx”, are each defined in the context of a sample of particles having disparate sizes; Dx represents the diameter of particles at which x% of all particles in the sample have diameters smaller than or equal to that diameter Dx (see p0028).
The disclosure further states that the Dx value is “a number distribution of the particles” and indicates that the values of D10, D50, and D90 are determined by dynamic light scattering (p0028).
Even further, the disclosure states that “[b]y approximation, it is understood that the pore size of a layer is about one fifth (i.e., 1/5 or 20%) of the mean particle size D50 of the primary particles forming the layer” (p0030). Thus, it is interpreted that if a prior art discloses a layer comprising inorganic particles as claimed and further discloses a pore size of the layer, a mean particle size D50 of the particles forming that layer is inherently approximately five times the disclosed pore size.
Finally, it is noted that Claim 11 requires that the membrane layer (i.e., the separating layer or the discriminating layer) consists of either TiO2 particles or ZrO2 particles.
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.
Claims 1, 3-11, and 21-25 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 1, as constructed, the added limitation “wherein the multilayered ceramic filtration element has a smaller mean pore size from the ceramic support structure to the at least one intermediate layer to the membrane layer” renders the claim indefinite because the comparative adjective “smaller” is lacking a subject, i.e., no subject has been introduced to compare the mean pore size of the multilayered ceramic filtration element. However, in the remarks filed by Applicant (02 June 2026), it is interpreted that this limitation is directed as a decreasing mean pore size in each successive layer of the multilayered ceramic filtration element from the ceramic support structure to the membrane layer. Claims 3-11 and 21-25 are also rejected due to their dependence on Claim 1.
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 (i.e., changing from AIA to pre-AIA ) 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.
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 and 3-10 is/are rejected under 35 U.S.C. 103 as being unpatentable over OYAMA et al. (US 2005/0172811 A1) in view of ONOZUKA et al. (US 2017/0259214 A1).
Regarding Claim 1, OYAMA discloses a permselective asymmetric membrane comprising a set of graded porous intermediate layers between a porous support and a membrane material (p0035). The porous intermediate layers are produced from a plurality of graded ceramic sol solutions with narrow, well-defined particle size distributions and are overlaid with a selective silica layer (i.e., a multilayered ceramic filtration element comprising a ceramic support structure… a membrane layer and at least one intermediate layer between the ceramic support structure and the membrane layer; p0016). The intermediate layers comprise materials including zirconia, titania, silicon nitride, silicon carbide, and boron nitride (i.e., wherein at least the membrane layer and the at least one intermediate layer comprise particles of at least one ceramic compound selected from the group consisting of metal oxides, metal carbides and metal nitrides; p0052). OYAMA discloses the intermediate layer is produced from ceramic sols with median particle sizes of 630, 200, 55, and 40 nm (p0048; FIGs. 2-4), which reads on the limitation wherein the at least one intermediate layer comprises particles with a particle size of D10 in the range of from 70 to 250 nm. As shown in FIGs. 3 and 4, the particle size distribution of each sol layer satisfies the limitation requiring the at least one intermediate layer comprises particles of the at least one ceramic compound with a Z-ratio D90/D10 of up to 4.
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OYAMA further discloses the porous support is sequentially dipped in solutions comprising median particle sizes of 630, 200, 55, and 40 nm (sol solutions p0048, sequential dipping p0071) resulting in a decreasing pore size distribution as summarized in Table 1 (i.e., 5.11 nm, 4.56 nm, and 3.73 nm for sol solutions of 630 nm, 200 nm, and 40 nm, respectively), i.e., wherein the multilayered ceramic filtration element has a smaller mean pore size from the ceramic support structure to the at least one intermediate layer to the membrane layer.
OYAMA is deficient in disclosing a ceramic support structure having a mean pore size of 0.5 to 1.5 µm.
ONOZUKA discloses a porous support-zeolite membrane composite (abstract). The porous support is an inorganic porous support comprising a ceramic, including silica, alumina, zirconia, titania, etc. (p0036). Further, the prior art discloses the average pore size of the porous support is 0.5 µm or more and 1.5 µm or less (p0039), which reads upon the claimed range of a mean pore size of from 0.5 to 1.5 µm. ONOZUKA discloses that the average pore size is advantageously within the disclosed ranges to increase permeation while maintaining composite strength (p0039). Thus, prior to the effective filing date of the claimed invention, one of ordinary skill in the art would have found it obvious to provide a ceramic support structure having a mean pore size of from 0.5 to 1.5 µm as taught by ONOZUKA for the ceramic porous support taught by OYAMA.
Regarding the limitation “[a] multilayered ceramic filtration element for liquid filtration”, the phrase “for liquid filtration” is directed toward an intended use of the claimed ceramic filtration element and holds no patentable weight. If the body of a claim fully and intrinsically sets forth all of the limitations of the claimed invention, and the preamble merely states, for example, the purpose or intended use of the invention, rather than any distinct definition of any of the claimed invention’s limitations, then the preamble is not considered a limitation and is of no significance to claim construction. Pitney Bowes, Inc. v. Hewlett-Packard Co., 182 F.3d 1298, 1305, 51 USPQ2d 1161, 1165 (Fed. Cir. 1999) (MPEP 2111.02 II).
Regarding Claim 3, modified OYAMA makes obvious the multilayered ceramic filtration element of Claim 1. OYAMA further discloses ceramic materials include zirconia, titania, silicon nitride, silicon carbide, and boron nitride (p0052).
Regarding Claim 4, modified OYAMA makes obvious the multilayered ceramic filtration element of Claim 1. OYAMA further discloses the intermediate layer being produced from ceramic sols having median particle sizes of 630, 200, 55, and 40 nm (p0048) having the particle distributions shown in FIGs. 2-4 (circle line CH3COOH in FIG. 2, triangle line 0.07 in FIG. 3, and upside down triangle line 72 h in FIG. 4), which reads on the limitation requiring that the at least one intermediate layer comprises particles with a particle size in the range of from 200 to 500 nm.
Regarding Claim 5, modified OYAMA makes obvious the multilayered ceramic filtration element of Claim 1. OYAMA further describes that the intermediate sol layer was prepared by sequentially dipping the support in successive sol solutions having sequentially smaller particle diameters (p0047, p0049). Such a process would result in the claimed limitations of at least two intermediate layers, wherein a first intermediate layer is directly supported on the ceramic support structure and a second intermediate layer is directly supported on the first intermediate layer; or at least three intermediate layers, wherein a first intermediate layer is directly supported on the ceramic support structure, a second intermediate layer is directly supported on the first intermediate layer, and a third intermediate layer is directly supported on the second intermediate layer.
Regarding Claims 6, 8, and 10, modified OYAMA makes obvious the multilayered ceramic filtration element of Claims 5 and 1. OYAMA further discloses all sol solutions include ceramic materials including zirconia, titania, silicon nitride, silicon carbide, and boron nitride (p0052).
Regarding Claim 7, modified OYAMA makes obvious the multilayered ceramic filtration element of Claim 5. OYAMA further discloses the intermediate layer being produced from ceramic sols having median particle sizes of 630, 200, 55, and 40 nm (p0048) having the particle distributions shown in FIGs. 2-4 (circle line 1.5 in FIG. 3, circle line 24 hr in FIG. 4), which reads on the limitation requiring that wherein the second intermediate layer comprises particles with a Z-ratio D90/D10 of up to 3, a particle size of D10 in a range of from 50 to 170 nm and a particle size D90 in the range of from 150 to 350 nm.
Regarding Claim 9, modified OYAMA makes obvious the multilayered ceramic filtration element of Claim 5. OYAMA further discloses the intermediate layer is produced from ceramic sols having median particle sizes of 630, 200, 55, and 40 nm (p0048) with particle distributions shown in FIG. 4 (square line 0.5 h in FIG. 4), which reads on the limitation requiring that wherein the second intermediate layer comprises particles with a Z-ratio D90/D10 of up to 3, a particle size of D10 in a range of from 50 to 170 nm and a particle size D90 in the range of from 150 to 350 nm.
Claim(s) 11 is/are rejected under 35 U.S.C. 103 as being unpatentable over OYAMA et al. (US 2005/0172811 A1) in view of ONOZUKA et al. (US 2017/0259214 A1) as applied to Claim 1 above, and further in view of BENFER et al. (Separation and Purification Technology, 2001, 22-23, pg. 231-237).
Regarding Claim 11, modified OYAMA makes obvious the multilayered ceramic filtration element of Claim 1. OYAMA further discloses all sol solutions include ceramic materials including zirconia, titania, silicon nitride, silicon carbide, and boron nitride (p0052). OYAMA further shows in FIG. 6 that the pore sizes of each successive layer of ceramic sol decreases from 5.1 nm to 4.6 nm to 3.7 nm, and thus, the expected pore size of the discriminating membrane layer would at least be less than 3.7 nm. Nevertheless, the prior art is explicitly deficient in disclosing the membrane layer consists of TiO2 particles with a Z-ratio D90/D10 of less than 3, a particle size D10 being in a range of from 5 to 9 nm, and a particle size D90 being in a range of from 9 to 15 nm or the membrane layer consists of ZrO2 particles with a Z-ratio D90/D10 of less than 5, a particle size D10 being in a range of from 1 to 3 nm, and a particle size D90 being in a range of from 3 to 5 nm.
However, such TiO2 and ZrO2 membrane layers have long been known as taught by BENFER. Utilizing a polymeric sol-gel process, BENFER produced composite membranes having a nanofiltration active separating layer supported on zirconia or titania ultrafiltration membranes (§2.1, par. 2). The prior art further determined the pore size distribution of a TiO2 and a ZrO2 nanofiltration membrane as shown in FIG. 7.
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While the prior art did not explicitly disclose the zirconia or titania particle sizes, based on Applicant’s disclosure, the approximate particle sizes for these two membranes would be about five times (i.e., 5x) the reported pore diameter, i.e., the titania membrane would have a peak diameter D50 at about 7.3 nm with a distribution range from as low as 2.5 nm to as high as 12 nm, and the zirconia membrane would have a peak diameter D50 at about 6 nm with a distribution range from as low as 1.5 nm to as high as 10.5 nm. Furthermore, based on FIG. 7 (see annotations), the TiO2 membrane D10 and D90 values conservatively seem to be at about 5.8 nm (1.15 in FIG. 7) and 9.0 nm (1.8 in FIG. 7), respectively, i.e., a Z-ratio D90/D10 would be less than 3, a particle size D10 being in a range of from 5 to 9 nm, and a particle size D90 being in a range of from 9 to 15 nm as claimed. All claimed elements were known in the prior art and one of ordinary skill in the art could have combined the elements as claimed by known methods with no change in their respective, individual functions, and the combination would have yielded nothing more than predictable results (MPEP §2143.01 A). Thus, one of ordinary skill in the art prior to the effective filing date of the claimed invention would have found it obvious to adapt BENFER’s taught titania membrane having the claimed particle sizes and Z-ratio to modified OYAMA’s membrane as both disclosures are directed toward nano-sized pores in ceramic composite membranes.
Allowable Subject Matter
Claims 21-25 are 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:
Regarding Claim 21, while OYAMA discloses the selective silica layer deposited on the intermediate layers is prepared by a method described in US Patent 6,527,833 (p0052). As disclosed in ‘833, such selective silica layers have a pore size of 3.6 nm (c8/20-22; FIG. 8). As further disclosed by OYAMA, the intermediate layer prepared from 630 nm sol particles produces a layer having an average pore size of 5.11 nm (Table 1). As further disclosed by ONOZUKA, the average pore size of the porous support is 0.5 µm or more and 1.5 µm or less (p0039). Thus, these disclosed mean pore sizes of 0.5 µm to 1.5 µm (porous support), 5.11 nm (intermediate layer), and 3.6 nm (selective layer), exceed the claimed range of differing respective mean pore sizes by 50-95%.
Regarding Claim 22, while OYAMA discloses reduced particle sizes in each subsequent layer of the intermediate layers, the prior art is deficient in citing a thickness in each subsequent layer also being reduced.
Regarding Claim 23, as noted for Claim 21, the porous support layer and the first intermediate layer have respective mean pore sizes that exceed the required limitation whereby the first layer of the two or more intermediate layers reduces the mean pore size of the ceramic support structure 60-95%.
Regarding Claim 24, as noted in Claim 1, OYAMA discloses successive intermediate layers having 5.11 nm and 4.56 nm mean pore sizes (i.e., for the layers prepared by the 600 nm sol solution and the 200 nm sol solution, respectively), which is only a 10.7% decrease in pore size, i.e., outside the claimed range of 87-95%.
Regarding Claim 25, as noted in Claim 1, OYAMA discloses successive intermediate layers having 4.56 nm and 3.73 nm for sol solutions of 200 nm and 40 nm, respectively, which is an 18.2% reduction, i.e., outside the claimed range of 55-80%.
While the cited art certainly discloses a decreasing pore gradient through successive layers of ceramic support layer, intermediate porous layers, and selective layer, none of the art discloses the claimed respective size reduction percentages between successive layers. The cited art is also silent as to the reduced thicknesses in successive intermediate layers as required by Claim 22. A careful search of additional prior art indicates that while it is known to provide decreasing thicknesses in the porous support layer, intermediate porous layer, and selective layer of a composite ceramic membrane (EBRAHIM et al., US 2020/0353424 A1; p0012, FIG. 1), there lacks motivation or a suggestion to modify modified OYAMA’s composite ceramic filtration membrane in such a way that would be obvious to one of ordinary skill in the art.
Conclusion
THIS ACTION IS MADE FINAL. 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 RYAN B HUANG whose telephone number is (571)270-0327. The examiner can normally be reached 9 am-5 pm 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, Vickie Kim can be reached at (571)272-0579. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/Ryan B Huang/Primary Examiner, Art Unit 1777
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