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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 30 January 2026 has been entered.
Priority
Applicant’s claim for the benefit of a prior-filed application (371 of PCT/JP2022/003206, filed 01/28/2022) under 35 U.S.C. 119(e) or under 35 U.S.C. 120, 121, 365(c), or 386(c) is acknowledged.
Acknowledgment is made of applicant’s claim for foreign priority (JP2021-027053, filed 02/24/2021) under 35 U.S.C. 119 (a)-(d). Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55. Should applicant desire to obtain the benefit of foreign priority under 35 U.S.C. 119(a)-(d) prior to declaration of an interference, a certified English translation of the foreign application must be submitted in reply to this action. 37 CFR 41.154(b) and 41.202(e).
Failure to provide a certified translation may result in no benefit being accorded for the non-English application.
Response to Amendments
Applicant’s amendments filed 30 January 2026 have been entered. Claims 2 and 15-22 have been canceled; Claims 11-14, 23, and 24 have been withdrawn; Claims 1, 6, and 11 have been amended; and new Claims 25-27 have been added. Overall, Claims 1, 3-14, and 23-27 are pending.
Applicant’s amendments with respect to the rejections of Claim(s) 1 and 3-10 under 35 U.S.C. 103 as being unpatentable over LONGO et al. (US 2018/0178149 A1) in view of ZHENG et al. (US 2022/0016570 A1) have been fully considered
Response to Arguments
Applicant’s arguments filed 30 January 2026 have been fully considered. Regarding the rejections of Claim(s) 1 and 3-10 under 35 U.S.C. 103 as being unpatentable over LONGO et al. (US 2018/0178149 A1) in view of ZHENG et al. (US 2022/0016570 A1), Applicant’s arguments have been fully considered and are persuasive.
Regarding LONGO, Applicant states that “claim 1 has been amended to recite that the coated solution can be left on the coated surface of the surface layer. This limitation clarifies that the coating solution for membrane formation is not intended to flow out through the back surface layer during membrane formation” (pg. 7, par. 2) and further “the coated solution substantially penetrates only into a surface layer region, so that the coated solution can be left on the coated surface (on a surface of the surface layer)” (pg. 7, par. 2). Applicant then states that comparatively, LONGO instead teaches a depth filter and that the intended use of LONGO contravenes the claimed pore sizes (pg. 8, par. 1): “contrary to the Examiner's assertions… a person having ordinary skill in the art understanding depth filters such as those taught in Longo would not have interpreted that a flow profile, in which inflow contacts a back layer support and exits an active layer, is common or expected” (pg. 8, par. 2). Applicant concludes arguing that such a modification renders LONGO “unsatisfactory for its intended purpose as a depth filter. See MPEP 2143.0l(V), which sets forth that "[i]f proposed modification would render the prior art invention being modified unsatisfactory for its intended purpose, then there is no suggestion or motivation to make the proposed modification. In re Gordon, 733 F.2d 900, 221 USPQ 1125 (Fed. Cir. 1984)” (pg. 8, par. 2).
The Examiner respectfully disagrees.
Applicant has recited intended uses (“the coating solution for membrane formation is not intended to flow out through the back surface layer during membrane formation”) of the claimed nonwoven fabric substrate. Intended uses are not given patentable weight. If a prior art structure is capable of performing the intended use as recited, then it meets the limitations of the claim (In re Schreiber, 128 F.3d 1473, 1477, 44 USPQ2d 1429, 1431 (Fed. Cir. 1997); MPEP §2111.02 II). Applicant has also recited features not actually claimed, i.e., that the coated solution penetrates only into a surface layer region. 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). Thus, Applicant’s argument that the intended use of LONGO and the proposed modification of LONGO by ZHENG renders the use of LONGO “unsatisfactory for its intended purpose” and thus would not be sufficient motivation for one of ordinary skill in the art to even contemplate is premised on features not claimed and on the intended use of the claimed substrate. Such an argument is misdirected; the modification of LONGO to include a protective coating resin is well-accepted in the art to be an obvious step in protecting membranes/filters from environmental conditions (as taught by ZHENG).
Regarding ZHENG, Applicant argues a “person having ordinary skill in the art would readily recognize that the dehydration membrane of Zheng is fundamentally different from the depth filter of Longo. In other words, a person having ordinary skill in the art would have lacked motivation to consider the features of the dehydration membrane of Zheng when researching the depth filter of Longo” (pg. 9, par. 2) and further that “thus from a practical standpoint, the thickness of the Longo' s depth filter is much larger than that of Zheng' s dehydration membrane. Therefore, a person having ordinary skill in the art would have readily recognized that the teachings of Zheng are incompatible with the depth filter of Long” (pg. 10, par. 1) and therefore, a person of ordinary skill in the art would not find it obvious to combine the cited references.
The Examiner agrees. It is noted that ZHENG discloses a protective coating for a separation membrane but does not indicate that such a separation membrane is a nonwoven fabric/filter. However, it is also noted that ZHENG discloses this protective coating can be applied to any composite membrane; while a nonwoven fabric/filter is not explicitly recited by ZHENG (as is required by the claimed invention and by LONGO), the claimed invention and the primary art do broadly require/disclose a composite membrane. As such, the original grounds of rejection are considered appropriate, and the claimed invention is unpatentable over the cited art. However, for the sake of compact prosecution and based on a new search and consideration, new grounds of rejection applying more relevant art has been made for Claim(s) 1, 3-10, and 25-27 under 35 U.S.C. 103 as being unpatentable over LONGO et al. (US 2018/0178149 A1) in view of TANIKAWA et al. (KR 20170131401 A).
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, 3-10, and 25-27 is/are rejected under 35 U.S.C. 103 as being unpatentable over LONGO et al. (US 2018/0178149 A1) in view of TANIKAWA et al. (KR 20170131401 A; machine translation provided and referenced herein).
Regarding Claim 1, LONGO discloses a multi-layer filter fabric having a first layer with a first non-woven fabric and a second layer having a second non-woven fabric, said filter fabrics having layers of differing median pore sizes (i.e., a nonwoven fabric substrate… including a nonwoven fabric; composed of two or more layers; abstract; p0002). In a filter fabric 10 shown in FIG. 1, fibers in layer 12 and fibers in layer 14 have different dtex (p0021-0022) ranging from about 0.4 denier to about 100 denier (p0012) and thereby, different median pore sizes (p0010, p0011). In one embodiment, layer 14 includes fibers of 5.9 dtex and fibers of 1.7 dtex (i.e., a surface layer), whereas layer 12 includes only fibers of 5.9 dtex (i.e., a back surface layer; the surface layer has an average pore diameter smaller than that of the back surface layer; p0021). Even further, LONGO discloses an embodiment with layer 12 having a thickness of about 0.030 inches to about 0.040 inches and layer 14 having a thickness of about 0.070 inches to about 0.090 inches for an overall filter fabric 10 thickness of 0.100 to about 0.130 inches (i.e., a thickness of the surface layer is 50% or more of the total thickness of the nonwoven fabric; p0023). LONGO further discloses the multi-layer filter fabric has a thickness in the range of about 0.005 inch to about 3.8 inches (p0015), which overlaps with the claimed range of a thickness of the nonwoven fabric is in a range of 30 to 300 µm and therefore, establishes a case of prima facie obviousness (MPEP 2144.05). LONGO is deficient in disclosing a surface of the surface layer is configured to be coated with a coating solution for membrane formation or that the coated solution can be left on the coated surface of the surface layer.
However, the recited limitation “a surface of the surface layer is configured to be coated with a coating solution” (emphases added) does not require the claimed nonwoven fabric substrate to include a coating solution. The instant limitation only requires that the surface of the surface layer be capable of being coated. There are no positively recited limitations requiring the presence of “a coated solution”. Similarly, the recited limitation of “so that the coated solution can be left on the coated surface of the surface layer” (emphases added) only requires the possibility of the coated solution being left on the surface. Such limitations are interpreted to only be optional limitations.
TANIKAWA discloses a composite film comprising a porous substrate and a porous layer containing a resin provided on one or both sides of the porous substrate (pg. 5, par. 5). The porous substrate itself is a composite microporous membrane comprising one or more laminated porous sheets on the microporous membrane (pg. 12, par. 8), e.g., two or more sheets (pg. 13, par. 2). The porous substrate is further disclosed to be a nonwoven fibrous material comprising one of polyethylene terephthalate, polyethylene, and polypropylene, etc. (pg. 13, par. 4) and further includes a functional layer laminated on the surface (pg. 13, par. 5). TANIKAWA discloses the porous substrate has a thickness ranging from 5 µm to 50 µm (pg. 13, par. 8) and that the overall composite film has a thickness of 5 µm to 100 µm (pg. 16, par. 1). Finally, TANIKAWA discloses the porous layer is applied as a coating liquid containing a resin onto one or both sides of the porous substrate (pg. 14, par. 6). 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).
The phrase “[a] nonwoven fabric substrate for a separation membrane” is directed toward a preamble that merely states the intended use of the claimed substrate. 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 limitation that “a difference between the average pore diameter of the surface layer and the average pore diameter of the back surface layer or the optional intermediate layer is 0.5 μm or more”, while LONGO is deficient in explicitly disclosing median pore sizes in layer 14 and layer 12, LONGO teaches that a desired pore size can be optimized by methods known in the art by selecting a denier and a density of the fibers in the layer (p0012). Further, because LONGO teaches the different layers of the filter fabric have different median pore sizes for the advantageous reasons of providing higher overall retention of particles and lower pressure drop compared with conventional filters (p0017, p0018) and further teaches the possible pore size range in each layer ranges from 0.010 µm to about 1.0 µm (p0017), the claimed limitation that “a difference between the average pore diameter of the surface layer and the average pore diameter of the back surface layer or the optional intermediate layer is 0.5 μm or more” would be obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention absent showings of criticality of such a 0.5 µm difference. Even further, such a difference is considered a matter of relative dimension. The only difference between the prior art and the claimed invention is a recitation of the relative dimensions of the devices. Because the claimed invention would not perform differently than that of modified LONGO, the claimed invention is not patentably distinct (Gardner v. TEC Syst., Inc., 725 F.2d 1338, 220 USPQ 777 (Fed. Cir. 1984), cert. denied, 469 U.S. 830, 225 USPQ 232 (1984); MPEP §2144.04).
Regarding Claim 3, modified LONGO makes obvious the nonwoven fabric substrate of Claim 1. As noted earlier, LONGO discloses layer 14 includes fibers of 5.9 dtex and fibers of 1.7 dtex, whereas layer 12 includes only fibers of 5.9 dtex (i.e., wherein the surface layer is composed of one or more kinds of fine fibers having a small fiber diameter and one or more kinds of thick fibers having a larger fiber diameter than the fine fibers; the back surface layer… are configured to include a portion consisting substantially of the thick fibers; p0021).
Regarding Claims 4 and 5, modified LONGO makes obvious the nonwoven fabric substrate of Claim 3. As noted earlier, LONGO discloses the fibers have various weights ranging from about 0.4 denier to about 100 denier (p0012). In one embodiment, layer 14 includes fibers of 5.9 dtex and fibers of 1.7 dtex, whereas layer 12 includes only fibers of 5.9 dtex (p0021). While this embodiment discloses fine fibers having a fiber diameter range outside the claimed ranges of 0.01 dtex or more and 0.5 dtex or less (Claim 4) and 0.05 dtex or more and 0.5 dtex or less (Claim 5) and a thick fiber having a fiber diameter range outside the claimed range of more than 0.5 dtex and 3.5 dtex or less (Claim 5), such differences between the prior art and the claimed invention are merely a matter of dimension. The only difference between the prior art and the claimed invention is a recitation of the relative dimensions of the devices. Because the claimed invention would not perform differently than the filter of the prior art given the same proportions and relative fiber diameter sizes and very similar two or more layer structure, the claimed invention is not patentably distinct (Gardner v. TEC Syst., Inc., 725 F.2d 1338, 220 USPQ 777 (Fed. Cir. 1984), cert. denied, 469 U.S. 830, 225 USPQ 232 (1984); MPEP §2144.04).
Regarding Claim 6, modified LONGO makes obvious the nonwoven fabric substrate of Claim 1. As noted earlier, LONGO discloses in an embodiment that the layer 12 has a thickness ranging from 0.030 inches to 0.040 inches and layer 14 has a thickness ranging from 0.070 inches to 0.090 inches (p0023), which yields a thickness composition ratio of 3:1 to 7:4, which reads on the claimed range of 5:5 to 9:1.
Regarding Claim 7, modified LONGO makes obvious the nonwoven fabric substrate of Claim 3. LONGO further discloses that the multi-layer fabric is produced such that each of the sublayers in the non-woven layers 12 and 14 are cross-lapped and even thermally bonded to adjacent layers (i.e., a portion in which fibers constituting the surface layer, the back surface layer… are continuously entangled between the layers; p0024).
Regarding Claim 8, modified LONGO makes obvious the nonwoven fabric substrate of Claim 1. LONGO further discloses the fibers comprise synthetic polymers including polyethylene, polypropylene, and bicomponent fibers such as polyethylene/polypropylene (p0013).
Regarding Claim 9, modified LONGO makes obvious the nonwoven fabric substrate of Claim 8. As noted earlier, LONGO discloses layer 14 includes fibers having different dtex, whereas layer 12 includes fibers having only one dtex (i.e., wherein materials of the surface layer, the back surface layer… are different from each other; p0021).
Regarding Claim 10, modified LONGO makes obvious the nonwoven fabric substrate of Claim 1. LONGO further discloses a chemical finish may be applied to the multi-layer filter fabric, thereby yielding increased pressure drop across the filter (i.e., wherein the nonwoven fabric substrate is subjected to a surface treatment for controlling wettability of the nonwoven fabric; p0026).
Furthermore, the limitation “wherein the nonwoven fabric substrate is subjected to a surface treatment for controlling wettability of the nonwoven fabric” is directed toward a manner or method by which the claimed substrate is used and is not subject to patentability. The manner or method in which an apparatus is to be utilized is not subject to the issue of patentability of the apparatus itself (In re Casey, 370 F.2d 576, 152 USPQ 235 (CCPA 1967); MPEP §2115). The claimed invention is directed to the substrate; not the subsequent surface treatments applied to the substrate thereafter.
Regarding Claim 25, modified LONGO makes obvious the nonwoven fabric substrate of Claim 1. TANIKAWA further discloses the porous layer is applied as a coating liquid containing a resin onto one or both sides of the porous substrate (i.e., wherein the coating solution for membrane formation is a resin solution; pg. 14, par. 6). Furthermore, LONGO discloses the median pore sizes of the fibrous fabric ranges from about 0.010 microns to about 1.0 microns, which is well within the claimed ranges of a microfiltration membrane (MF membrane), an ultrafiltration membrane (UF membrane), a nanofiltration membrane (NF membrane), or a reverse osmosis membrane (RO membrane).
Regarding Claim 26, modified LONGO makes obvious the nonwoven fabric substrate of Claim 1. LONGO further discloses the multi-layer filter fabric has a thickness in the range of about 0.005 inch to about 3.8 inches (p0015), which overlaps with the claimed range of the thickness of the nonwoven fabric is in a range of 60 to 200 µm and therefore, establishes a case of prima facie obviousness (MPEP 2144.05).
Regarding Claim 27, modified LONGO makes obvious the nonwoven fabric substrate of Claim 26. As noted, LONGO further discloses the multi-layer filter fabric has a thickness in the range of about 0.005 inch to about 3.8 inches (p0015). While this range just borders the claimed range of 60 to 126 µm, LONGO further teaches that the thickness of the multi-layer filter fabric is dependent on the expected use of the fabric, e.g., depending on the required mechanical strength, the desired pressure drop, and/or the expected particulate load to be retained by the filter fabric (p0015). As such, if these factors are considered, one of ordinary skill in the art would find the claimed thickness range of 60 to 126 µm obvious over the prior art. Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation absent unexpected results or evidence indicating such optimum or workable ranges are critical (In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955); MPEP§2144.05).
Conclusion
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.
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/Ryan B Huang/Primary Examiner, Art Unit 1777
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