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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 25 November 2025 has been entered.
Priority
Applicant’s claim for the benefit of a prior-filed application (DIV of 17/115,054, filed 08 December 2020) under 35 U.S.C. 119(e) or under 35 U.S.C. 120, 121, 365(c), or 386(c) is acknowledged.
Claim Interpretation
The claims recite the abbreviation “CTE”. Although nowhere explicitly defined in the disclosure, CTE is accepted in the art to represent the coefficient of thermal expansion and is a measure of how much a material expands as its temperature changes in units of ppm/°C. Further, CTE is considered a material property; therefore, a specific CTE value is inherent for any given material.
The claims recite a phrase “tear-resistance” with respect to a “tear-resistant boundary region” wherein “the tear-resistant boundary region has a tear-resistance that is greater than that of the pore region” in Claim 1. This implies that “tear-resistance” is a measurable quantity useful for comparing between the boundary region and the pore region. However, the disclosure of the invention fails to provide any quantifiable means of measuring “tear-resistance”. Paragraph 0005 suggests that “[t]he greater tear resistance can come from one or more factors including the region having no pores, the region having a lower density of pores, and/or a region having thicker structures between pore regions”. No other disclosure provides indications of how “tear-resistance” can be quantified. As such, the Examiner interprets “tear-resistance” to be based on the presence of pores in a region, i.e., the more pores, the lower the “tear-resistance”; the higher the pore density, the lower the “tear-resistance”. So long as a “boundary region” has fewer pores or a lower pore density than a “pore region”, then the boundary region will be considered to have greater “tear-resistance”.
The claims recite a phrase “aspect ratio” with respect to the pores in Claims 3 and 4: “wherein the pores have an aspect ratio ranging from 0.5:1 to 20:1” and “wherein the pores have an aspect ratio ranging from 2:1 to 5:1”. The specification discusses “aspect ratio” and identifies it to be related to the thickness of the membrane and the diameter of the pores: “The thickness of the membrane together with the diameter of the pores determines the aspect ratio of the pores. The thickness of the membrane will often be within the range of 5 to 25 microns” (p0040) and further states “the pores are designed to have dimensions ranging from 1-100 microns…. [o]ne preferred membrane filter has a membrane thickness of 10 microns with pores that have an exit diameter of 2 microns” (p0039). This indicates that the claimed “aspect ratio” is the ratio of membrane thickness to pore diameter.
Response to Amendments
Applicant’s amendments filed 27 October 2025 have been entered.
Applicant indicated Claim 1 has been amended; however, there appears to be no amendments filed for Claim 1. Claims 7 and 8 have been canceled; and new Claims 26-29 have been added. Claims 1-7 and 25-29 are pending.
Applicant’s amendments have been fully considered, but are not persuasive. To further advance prosecution, the prior art rejections have been slightly modified to include evidentiary support; however, the grounds of rejection remain the same. Claims 1-7 and 25-29 are rejected under 35 U.S.C. 103 as being unpatentable over ZHENG et al. (US 2009/0188864 A1) in view of GRILLE et al. (US 9,610,543 B2) with evidentiary support from LIU et al. (RSC Adv., 2018, 8, 19034).
Response to Arguments
Applicant’s arguments filed 27 October 2025 have been fully considered.
Regarding the rejections of Claim(s) 1-9 and 25 under 35 U.S.C. 103 as being unpatentable over ZHENG in view of GRILLE, Applicant argues the presently amended claims includes the limitation: "a polymeric film on a support substrate, the polymeric film comprising polyimide having a CTE that is within ±25% of 3.2 ppm/°C and having a plurality of liquid-filtering tear-resistant porous membrane filters”; i.e., such a limitation allows for the removal of the polymer from the substrate without curling upon delamination (pg. 6, par. 1-2). For this reason, Applicant argues the present invention is non-obvious over the prior art.
The Examiner respectfully disagrees.
It is noted that independent Claim 1 does not recite the argued limitations. Thus, at least for independent Claim 1, Applicant’s arguments are not in commensurate with the scope of the recited invention. In effect, the argued limitations are merely disclosed in the Specification, and not in Claim 1. 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).
Further, Applicant argues the “concept” of the claimed CTE limitation is not taught or suggested by the prior art. However, CTE is a material property of the claimed polymeric film; because Applicant has only claimed “polymeric film” in Claim 1 and has not provided any further limitation or specificity beyond “polymeric film”, so long as the prior art teaches the same claimed polymeric film, the recited CTE limitation is inherent. The claiming of a new use, new function or unknown property which is inherently present in the prior art does not necessarily make the claim patentable (In re Best, 562 F.2d 1252, 1254, 195 USPQ 430, 433 (CCPA 1977)).
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) 1-7 and 25-29 is/are rejected under 35 U.S.C. 103 as being unpatentable over ZHENG et al. (US 2009/0188864 A1) in view of GRILLE et al. (US 9,610,543 B2) with evidentiary support from LIU et al. (RSC Adv., 2018, 8, 19034).
Regarding Claim 1, ZHENG discloses a microfabricated porous membrane comprising multiple filter patches arranged in microfiltration arrays (i.e., porous membrane filters; p0051, p0100; FIGs. 13, 14). The porous membrane 511, 521 is prepared on a substrate 601 (i.e., on a support substrate; p0104; p0105; FIGs. 15A-D) and is prepared from polyimide, polycarbonate, TEFLON, polysiloxane, and polyacrylate (i.e., a polymeric film; p0094). Each filter patch 500 comprises a filter array having multiple pores 513, 523 (p0100).
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Said pores are defined by photolithography (i.e., a photolithographically defined pore region defining a central region of the membrane filter, the pore region comprising a plurality of pores; p0104); during lithography, membrane layers 521 and 511 are etched to produce the pores 513, 523 to expose the underlying substrate 601 on which the membrane is prepared (i.e., the plurality of pores extending through the polymeric film and exposing the support substrate; p0104, FIG. 5A-D).
ZHENG further discloses the pores 513, 523 are circular and have diameters 40 µm and 8 µm, respectively (p0102), which reads on the claimed range of a plurality of pores having a minimum dimension of less than 100 microns. As further shown in FIG. 13 the edges of each filter patch lack pores or have lower pore density than the central region of the filter patch (i.e., a tear-resistant boundary region, the tear-resistant boundary region substantially surrounding the pore region, wherein the tear-resistant boundary region has a tear-resistance that is greater than that of the pore region; FIG. 13).
ZHENG is deficient in explicitly disclosing a photolithographically defined segmentation region surrounding both the pore region and the tear-resistant boundary region such that the tear-resistant boundary region is between the pore region and the segmentation region, the segmentation region being defined by holes extending through the polymeric film and exposing the support substrate.
GRILLE discloses methods for structuring a substrate utilizing photolithographic techniques and providing perforation structures to kerf regions to obtain shaped individual chips from the larger substrate (abstract). Said perforation structures comprise a plurality of through-holes exposing the substrate (c2/1-2; c5/46-50). The method involves performing photolithography to mark a plurality of sites corresponding to perforation structures and kerf regions to prepare a plurality of individual chip to be obtained from the substrate (c4/65-c5/9). Advantageously, such a procedure yields substantially stress-free substrates and avoids the potentially structurally damaging mechanical separation of individual chips from other chips on the substrate (c5/10-17). 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 perforation region surrounding individual chips as taught by GRILLE for each filter patch taught by ZHENG to provide for damage-free more easily separated filter patches.
Furthermore, regarding the limitation “liquid-filtering tear resistant”, such a limitation is directed toward uses (i.e., “liquid-filtering”) and properties (i.e., “tear resistant”) of the claimed polymeric membrane substrate. 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); i.e., whether the claimed substrate is used to filter liquids has no bearing on the patentability of the substrate itself. The claiming of a new use, new function or unknown property which is inherently present in the prior art does not necessarily make the claim patentable (In re Best, 562 F.2d 1252, 1254, 195 USPQ 430, 433 (CCPA 1977)); i.e., the prior art of record discloses or makes obvious all structural and functional limitations and thus, the cited properties are necessarily and inherently present.
Finally, regarding the recited limitation “the polymeric film having a CTE that is within 25% of that of the support substrate”, although the prior art is deficient in explicitly disclosing CTE values for the polymeric film or the support substrate, ZHENG discloses the preparation of filtration membranes via microfluidic techniques (p0013) wherein the polymeric membrane 511, 521 comprises polyimide material (p0094) and the support substrate 601 is silicon (p0104). As evidenced by LIU, to maintain mechanical properties and thermal stability for polyimide-based films supported on silicon substrates and to further prevent “cracking or peeling of the PI film”, it is advantageous to minimize “the mismatch in the CTE between the PI film and substrate”, e.g., maintain a CTE of less than 10 ppm °C-1 for PI films (§1. Introduction, pg. 19034, par. 1). Thus, one of ordinary skill in the art, as evidenced by LIU, would find it obvious to maintain a polymeric film having a CTE that is within 25% of that of the support substrate, especially the polyimide membrane and silicon substrate taught by ZHENG.
Regarding Claim 2, modified ZHENG makes obvious the membrane of Claim 1. ZHENG further discloses the membrane is dual layered and each layer is 10 µm thick (p0104), which reads on the claimed range of a thickness that ranges between 5 to 25 microns.
Regarding Claims 3 and 4, modified ZHENG makes obvious the membrane of Claim 1. ZHENG further discloses the pores 513, 523 are circular and have diameters 40 µm and 8 µm, respectively (p0102), and that the membrane is dual layered and each layer is 10 µm thick (p0104), which corresponds with a thickness:diameter aspect ratio of 20:40 and 20:8 (i.e., 0.5:1 and 2.5:1), which reads on the claimed range of an aspect ratio ranging from 0.5:1 to 20:1 (Claim 3) and overlaps with the claimed aspect ratio ranging from 2:1 to 5:1 (Claim 4), thereby establishing a case of prima facie obviousness (MPEP 2144.05).
Regarding Claim 5, modified ZHENG makes obvious the membrane of Claim 1. As noted earlier, ZHENG shows circular pores 513 with diameter 40 µm (p0102), which reads on the claimed range of the minimum dimension being at least 20 nm.
Regarding Claims 6 and 7, modified ZHENG makes obvious the membrane of Claim 1. While ZHENG does not explicitly disclose a central pore region having a “circular shape” or that the tear-resistant boundary region has a “ring shape” in the instant embodiment, other embodiments by ZHENG does show filter patches being generally a hexagonal shape (e.g., FIGs. 2, 3, and 4c), which is considered by one of ordinary skill in the art to be “a ring shape” and “circular shape” as claimed. Even further, ZHENG does disclose that “other embodiments may have filter patches having different shapes” (p0048). The configuration of the claimed invention is a matter of choice which one of ordinary skill in the art prior to the effective filing date of the invention would have found obvious absent persuasive evidence that the claimed particular configuration was significant and would yield unexpected results (In re Dailey, 357 F.2d 669, 149 USPQ 47 (CCPA 1966); MPEP §2144.04). Thus, the claimed “circular shape” and “ring shape” would have been obvious to one of ordinary skill in the art.
Regarding Claim 25, modified ZHENG makes obvious the membrane of Claim 1. ZHENG is deficient in explicitly disclosing the polymeric film has a surface area of 4,000 mm2 or greater. However, such a disclosure is merely directed toward a difference in dimension between the prior art and the claimed invention. 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 ZHENG, 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 Claims 26-28, modified ZHENG makes obvious the membrane of Claim 6. ZHENG is deficient in explicitly disclosing “the pore region has a diameter ranging between 0.5 to 25 cm” (Claim 26) or “the tear prevention region has a width within the range of 0.5 and 5 mm” (Claims 27 and 28). However, such disclosures are merely directed toward differences in dimension between the prior art and the claimed invention. 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 ZHENG, 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 29, modified ZHENG makes obvious the membrane of Claim 1. Regarding the limitation "the polymeric film is polyimide having a CTE that is within ±25% of 3.2 ppm/°C”, it is noted that ZHENG discloses the porous membrane is prepared from polyimide (p0094). Although the prior art is deficient in explicitly disclosing CTE values for the polyimide, as evidenced by LIU, it would be advantageous to maintain the mechanical properties and thermal stability for polyimide-based films supported on silicon substrates and to further prevent “cracking or peeling of the PI film” by minimizing“the mismatch in the CTE between the PI film and substrate”, e.g., maintain a CTE of less than 10 ppm °C-1 for PI films (§1. Introduction, pg. 19034, par. 1). Thus, one of ordinary skill in the art, as evidenced by LIU, would find it obvious to maintain a polymeric film having a CTE that is within ±25% of 3.2 ppm/°C, especially the polyimide membrane and silicon substrate taught by ZHENG.
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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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, In Suk Bullock can be reached at 571-272-5954. 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
Prosecution Insights