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
Applicant’s claim for the benefit of a prior-filed application (PRO 63/303,571, filed 01/27/2022) under 35 U.S.C. 119(e) or under 35 U.S.C. 120, 121, 365(c), or 386(c) is acknowledged.
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 23 December 2025 has been entered.
Claim Interpretation
Claims 1 and 20 recite the phrase “wherein the liquid infused membrane does not exhibit gating upon removal of the transmembrane pressure”. As explained in p0041 of the Specification:
The term "gating" as used herein refers to refilling of the pores with the oil to effectively seal the pore when flow of a fluid through the membrane is stopped (i.e., the pressure is decreased). In a gating system, a minimum (threshold) pressure will be required each time flow is started through the membrane in order to open the pores and allow transport of the fluid. The liquid infused membranes disclosed herein do not exhibit gating when the system pressure is decreased.
And further, in p0081, “‘Gating mechanism’ refers to on applying pressure, the liquid is pressed against the pore walls allowing the filtration liquid to pass and when this pressure is released, the pores can be refilled by the liquid”. Thus, as described, the claimed liquid infused membrane is interpreted to not require a minimum/threshold pressure to open the pores of the membrane to allow for the transport of fluid due to a combination of the pores having a sufficient size and the liquid having a sufficient viscosity so as to prevent the liquid from sealing the pores. Such pore sizes and liquid viscosities are considered “sufficient” within their respective claimed ranges, i.e., Claims 1 and 20 (0.1 to 0.25 µm average pore diameter) and Claim 12 (75 to 90 cSt at 20°C).
Response to Amendment
Applicant’s amendments filed 08 December 2025 have been fully considered.
Regarding the rejection of Claim 3 under 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, 4th paragraph, as being of improper dependent form, Applicant’s amendments are sufficient; this rejection has been withdrawn. Specifically, amending “threshold pressure” to specify “an initial threshold pressure” obviates the confusion with the requirement in Claim 1 that the liquid infused membrane does not exhibit gating upon removal of a transmembrane pressure.
Regarding the rejections of Claim(s) 1-8, 11, 14, 15, 19, and 20 under 35 U.S.C. 102(a)(1)/(a)(2) as being anticipated by AIZENBERG et al. (US 2014/0187666 A1) and Claim(s) 10 and 12 under 35 U.S.C. 103 as being unpatentable over AIZENBERG et al. (US 2014/0187666 A1), Applicant’s amendments are not sufficient to overcome the rejections except for Claim 15, which has been canceled; the rejections are maintained for Claim(s) 1-8, 11, 14, 19, and 20 under 35 U.S.C. 102(a)(1)/(a)(2) as being anticipated by AIZENBERG et al. (US 2014/0187666 A1) and Claim(s) 10 and 12 under 35 U.S.C. 103 as being unpatentable over AIZENBERG et al. (US 2014/0187666 A1).
The declaration under 37 CFR 1.132 filed 08 December 2025 is insufficient to overcome the rejection of Claims 1 and 20 (incorporating relevant limitations from now-canceled Claim 15) based upon 35 U.S.C. 102(a)(1)/(a)(2) as being anticipated by AIZENBERG et al. (US 2014/0187666 A1) as set forth in the last Office action because: the disclosure of AIZENBERG is not subject to the exceptions of 35 USC 102(b)(1)(A) or 35 USC 102(b)(2)(A), i.e., the prior art disclosure is a US patent or US patent application publication that was made more than one year before the effective filing date of the claimed invention. See MPEP 717.01 subsection II(B). Furthermore, the disclosure of AIZENBERG is not subject to the exceptions of 35 USC 102(b)(2)(A), i.e., the prior art disclosure does not include subject matter obtained directly or indirectly from the inventor or a joint inventor.
Response to Arguments
Applicant’s arguments filed 08 December 2025 with respect to the anticipation rejections over AIZENBERG (pg. 8-11) and the obviousness rejections over AIZENBERG (pg. 11-13) have been fully considered but are not persuasive.
Regarding the anticipation rejections over AIZENGERG (pg. 8-11), Applicant argues that as-amended Claims 1 and 20 now at least require the limitation that an average pore diameter of 0.1 to 0.25 µm is not taught by AIZENBERG and thus, the claims are not anticipated by AIZENBERG (pg. 10, top). Applicant further argues previous Claim 15 (now canceled) had claimed a range of 0.1 to 20 µm and the now claimed range of 0.1 to 0.25 µm is a “significantly narrowed range” renders AIZENBERG’s disclosure of pore sizes “spanning 50 nanometers to 100 micrometers is not sufficiently specific to anticipate Applicants’ claimed range of 0.1 to 0.25 micrometers” (pg. 10, middle). Further, Applicant argues amended Claim 20 additionally requires the plurality of pores are interconnected and that “there is nothing in Aizenberg to specifically lead the skilled person to an interconnected porous structure as required by present claim 20. Rather, at best, Aizenberg discloses the columnar porous structure in FIG. 5B, where these pores are expressly not interconnected” (pg. 11, top). For these reasons, Applicant argues Claims 1-8, 11, 14, 19, and 20 are not anticipated by AIZENBERG.
Regarding the obviousness rejections over AIZENGERG (pg. 11-13), Applicant argues that Claims 10 and 12 would not have been obvious over AIZENBERG because Claim 1 from which both Claims 10 and 12 depend would not have been obvious over AIZENBERG (pg. 12, top). Applicant references the same arguments presented for the rejection of Claim 1 and further discusses the Declaration under 37 CFR 1.132 wherein the inventors “surprisingly found that membranes with average pore diameters in the claimed range exhibit superior lubricant retention and pressure stability” demonstrating that the claimed range “is not arbitrary” (pg. 12, bottom). Further, Applicant argues the declaration showed data establishing a nexus between the recited average pore diameter range and observed oil retention and pressure stability, i.e., features not observed for pore sizes above the claimed range (pg. 12-13). For these reasons, Applicant argues the claims are patentable over AIZENBERG.
The Examiner respectfully disagrees.
Arguments pertaining to both the anticipation rejections and obviousness rejections over AIZENBERG will be addressed concurrently. As noted in the subsequent prior art rejection, AIZENBERG does in fact explicitly disclose a pore size of 0.2 µm, which is entirely within the claimed range of 0.1 to 0.25 µm. Thus, Applicants’ arguments, which are predicated on the basis of AIZENBERG not teaching the as-amended narrower claimed range, are obviated. The prior art is indeed “sufficiently specific” to anticipate Applicants’ claimed pore size range. Even further, AIZENBERG also explicitly discloses the pores have an interconnected structure; thus, Applicants’ arguments with respect to amended Claim 20 are also obviated.
With respect to the 37 CFR 1.132 declaration b the inventors, it is noted that the claimed invention has been rejected under 35 USC 102(a)(1)/(a)(2). As such, the disclosure of AIZENBERG (having no common inventors) is not subject to 102(b)(1)(A) nor 102(b)(2)(A) exceptions, and therefore, the 37 CFR 1.132 is inappropriate as no obviousness rejection has been put forth for independent Claims 1 and 20.
Applicant’s request for rejoinder of withdrawn Claims 9, 13, and 16 (pg. 13) has been considered but is moot given that independent Claim 1 remains rejected as noted.
Claim Rejections - 35 USC § 102
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 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.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claim(s) 1-8, 11, 14, 19, and 20 is/are rejected under 35 U.S.C. 102(a)(1)/(a)(2) as being anticipated by AIZENBERG et al. (US 2014/0187666 A1).
Regarding Claims 1 and 20, AIZENBERG discloses slippery liquid-infused porous surfaces (SLIPS; abstract, p0013). The prior art discloses an article comprising a substrate having an upper surface and a lubricating fluid adhered to/wetting the substrate to form a liquid upper surface (p0014-0020). The substrate is porous (p0039, p0115-0118) and comprises a polymer including polyvinylidene fluoride (i.e., a porous fluorine-containing polymer membrane having a first surface and a second surface and comprising a plurality of pores; p0051, p0127). The prior art discloses that the substrate has a plurality of three-dimensionally interconnected network of pores (i.e., wherein one or more of the plurality of pores extend from the first surface to the second surface of the porous fluorine-containing membrane to provide at least one continuous path from the first surface to the second surface; p0049, p0117). While the prior art is deficient in explicitly disclosing that each pore is defined by a pore wall, such a structural requirement is inherent in any pore and is anticipated by the mere disclosure of a pore (i.e., each pore defined by a pore wall). Even further, the requirement that the pore wall comprises a fluorine-containing polymer is also anticipated by the disclosure that the substrate comprises porous structures comprising polymers including polyvinylidene fluoride (i.e., the pore wall comprises a fluorine-containing polymer; p0127). The prior art further discloses the substrate as having pore size ranges of from about 50 nm to about 100 µm (p0214), e.g., 0.2 µm (p0275), which reads upon the claimed range of an average pore diameter of 0.1 to 0.25 µm.
AIZENBERG further discloses the lubricating fluid includes perfluoropolyethers, such as KRYTOX 103 (Table 1; p0152); said lubricating fluid creates a fluid surface on the substrate and may further infiltrate into the pores (i.e., a perfluoropolyether oil coating on at least a portion of the first surface and at least a portion of the pore wall; p0148, p0160, p0161).
The limitation “wherein a fluid can pass through the membrane when a transmembrane pressure is applied” is directed toward intended uses, a material and article worked upon, and a manner or method of using the claimed membrane. 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). The inclusion of material or article worked upon by a structure being claimed does not impart patentability to the claims (In re Young, 75 F.2d 996, 25 USPQ 69 (CCPA 1935); MPEP §2115). 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). Such a limitation further only requires the membrane to have the capability to allow a fluid to pass through.
It is noted that the disclosed lubricating fluid, i.e., KRYTOX 103 (see Table 1, p0156), has a viscosity at 20°C of 0.82 cm2/sec (i.e., 82 cSt) and that the prior art discloses pore size ranges of from about 50 nm to about 100 µm (p0214), e.g., 0.2 µm (p0275), which when combined are considered to have sufficient viscosity and sufficient pore size so as to enable the liquid-infused membrane to not exhibit gating as described in the Specification and as explained in §Claim Interpretation. Furthermore, the limitation requiring “the liquid-infused membrane to not exhibit gating upon removal of the transmembrane pressure” is directed toward an intended result necessarily expected from the use of the membrane and is not subject to patentability. Claim scope is not limited by claim language that suggests or makes optional but does not limit a claim to a particular structure. Because the prior art, singly or in combination, teaches all claimed structural language, the “adapted to” or “adapted for” clause in question is optional and does not limit the claim. The clause expresses the intended use of the claimed structural element and thereby, does not further limit the claim (MPEP §2111.04). Even further, because the prior art discloses all structural and functional limitations of the claim, this intended result is necessarily expected.
Regarding Claim 2, AIZENBERG discloses the liquid infused membrane of Claim 1. Any transmembrane pressure applied to the membrane is considered an initial threshold pressure and thus, reads on the claimed limitation exhibiting an initial threshold pressure above which at least a portion of the perfluoropolyether oil coating is displaced to allow the fluid to pass through the membrane. Further, a zero pressure is also considered to read on the claimed “initial threshold pressure”.
Regarding Claim 3, AIZENBERG discloses the liquid infused membrane of Claim 1. The instant limitation requiring “the liquid infused membrane does not exhibit an initial threshold pressure to allow the fluid to pass through the liquid infused membrane” is directed toward an intended result necessarily expected from the use of the membrane and is not subject to patentability. Claim scope is not limited by claim language that suggests or makes optional but does not limit a claim to a particular structure. Because the prior art, singly or in combination, teaches all claimed structural language, the “adapted to” or “adapted for” clause in question is optional and does not limit the claim. The clause expresses the intended use of the claimed structural element and thereby, does not further limit the claim (MPEP §2111.04). Even further, because the prior art discloses all structural and functional limitations of the claim, i.e., the porous fluorine-containing polymer membrane comprising a plurality of pores of an average pore diameter of 0.1 to 0.25 µm, and a perfluoropolyether oil coating on at least a portion of the first surface and pore walls wherein said perfluoropolyether oil coating includes properties that when combined with the claimed membrane are admitted by Applicant to not exhibit gating, this intended result is necessarily expected.
Regarding Claims 4 and 5, AIZENBERG discloses the liquid infused membrane of Claim 1. The instant limitations “wherein the liquid infused membrane exhibits pure water permeance at a transmembrane pressure of greater than or equal to 1 bar, pure oil permeance at a transmembrane pressure of less than or equal to 5 bar, or both” (Claim 4) and “wherein the pure water permeance is less than the pure water permeance of the porous fluorine-containing polymer membrane not including the perfluoropolyether oil, wherein the pure oil permeance is less than the pure oil permeance of the porous fluorine-containing polymer membrane not including the perfluoropolyether oil, or both” (Claim 5) are directed toward intended uses, materials and articles worked upon, and manners or methods of using the claimed membrane. 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). The inclusion of material or article worked upon (pure water and pure oil) by a structure being claimed does not impart patentability to the claims (In re Young, 75 F.2d 996, 25 USPQ 69 (CCPA 1935); MPEP §2115). 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).
Regarding Claim 6, AIZENBERG discloses the liquid infused membrane of Claim 1. AIZENBERG further discloses the substrate comprises a polymer including polyvinylidene fluoride (i.e., wherein the fluorine-containing polymer membrane comprises polyvinylidene fluoride; p0051).
Regarding Claims 7, 8, and 11, AIZENBERG discloses the liquid infused membrane of Claim 1. AIZENBERG further discloses KRYTOX 103 as one of the liquids (p0156, Table 1), which has a structure of F-(CF(CF3)-CF2-O)n-CF2CF3 where n ranges from 10 to 60 and a viscosity of 82 cSt at 20°C.
Regarding Claim 14, AIZENBERG discloses the liquid infused membrane of Claim 1. The instant limitation “wherein the liquid infused membrane reduces adhesion of bacteria by at least 45% relative to a porous fluorine-containing polymer membrane not including the perfluoropolyether oil” is directed toward an intended use, materials and articles worked upon, and manners or methods of using the claimed membrane. 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). The inclusion of material or article worked upon by a structure being claimed does not impart patentability to the claims (In re Young, 75 F.2d 996, 25 USPQ 69 (CCPA 1935); MPEP §2115). 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).
Regarding Claim 19, AIZENBERG discloses a liquid infused membrane as described in the rejection of Claim 1. Some applications of the disclosed membrane include filter papers (p0126), i.e., which is usable for water purification and/or oil purification. Furthermore, the limitation “[a] water purification system or an oil purification system” is directed toward a preamble limitation having no patentable weight and merely states the purpose or intended use of the claimed membrane. 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).
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) 10 and 12 is/are rejected under 35 U.S.C. 103 as being unpatentable over AIZENBERG et al. (US 2014/0187666 A1).
Regarding Claim 10, AIZENBERG discloses a liquid infused membrane of Claim 1. AIZENBERG further discloses that the amount of lubricating fluid provided to the surface is at a “sufficient quantity” to “wet the entire roughened surface structure and form an ultra-smooth film over the underlying roughened surface” (p0160). AIZENBERG further discloses “wicking 100 µL” of lubricating fluid onto 30 mm round TEFLON filter membranes (p0275); while weights are not disclosed, the prior art nevertheless discloses amounts from which a weight ratio of perfluoropolyether oil to membrane can be calculated. 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). Thus, the claimed weight ratio of oil:membrane of 0.2:1 to 1.5:1 would be obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention.
Regarding Claim 12, AIZENBERG discloses a liquid infused membrane of Claim 11. AIZENBERG further discloses KRYTOX 103 as one of the liquids (p0156, Table 1), which has a structure of F-(CF(CF3)-CF2-O)n-CF2CF3 where n ranges from 10 to 60 and a viscosity of 82 cSt at 20°C, which read on the claimed perfluoropolyether oil having a viscosity of 75 to 90 cSt at a temperature of 20°C.
AIZENBERG further discloses that the amount of lubricating fluid provided to the surface is at a “sufficient quantity” to “wet the entire roughened surface structure and form an ultra-smooth film over the underlying roughened surface” (p0160). AIZENBERG further discloses “wicking 100 µL” of lubricating fluid onto 30 mm round TEFLON filter membranes (p0275); while weights are not disclosed, the prior art nevertheless discloses amounts from which a weight ratio of perfluoropolyether oil to membrane can be calculated. 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). Thus, the claimed weight ratio of oil:membrane of 0.3:1 to 0.5:1 would be obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention.
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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