DETAILED ACTION
This action is in response the RCE amendments and remarks dated 12/02/2025 in which claims 1, 10 and 12 have been amended, claims 27-29 have been newly added, and claims 1-2, 6-13, 18, 22, 24 and 27-29 are pending, claims 9-13, 18, 24 and 28 are withdrawn as directed to a non-elected invention and thus claims 1-2, 6-8, 22, 27 and 29 are ready for examination. Note: new claim 28 depends from claim 10 and is therefore withdrawn along with claim 10.
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 12/02/2025 has been entered.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
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 1-2, 6-8, 22, 27 and 29 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention. Claim 1 recites the limitation “a concentration of polyethylene forming the tight side being greater than a concentration of polyethylene forming the open side”. This limitation is so broad as to make it unclear if this refers to the concentrations of polyethylene in the formed membrane sides (i.e. a structural limitation) or the concentrations of polyethylene in the solutions used to form the different membrane sides (a product-by-process limitation). The specification only discusses concertation of polyethylene in the solutions used to form the membrane sides, thus the specification does not support this limitation which may be interpreted more broadly. Claims 2, 6-8, 22, 27 and 29 are rejected for depending from claim 1.
Claims 1-2, 6-8, 22, 27 and 29 are rejected under 35 U.S.C. 112(b) 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.
Claim 1 recites the limitation “a concentration of polyethylene forming the tight side being greater than a concentration of polyethylene forming the open side”. It is not clear if this refer to the concentrations of polyethylene in the formed membrane sides (i.e. a structural limitation) or the concentrations of polyethylene in the solutions used to form the different membrane sides (a product-by-process limitation). As the specification only discusses concertation of polyethylene in the solutions used to form the membrane sides, this is how it will be interpreted, i.e. as a functional limitation, because the alternative would not be supported by the specification.
Claims 2, 6-8, 22, 27 and 29 are rejected for depending from an indefinite claim.
Claim Interpretation
“Mean Bubble Point Test" ” is defined in the instant specification [0042] to mean: “A dry sample of a membrane is placed on a holder a gas pressure is gradually applied to the tight side of the dry membrane using compressed air. The air flow rate through the dry membrane is measured as a function of pressure. Next the membrane is wetted with ethoxy-nonafluorobutane HFE-7200 (available from 3M). Gas pressure is gradually applied to the tight side of the wetted membrane using compressed air. The air flow rate through the wetted membrane is measured as a function of pressure. This test is performed at ambient temperature (e.g., at approximately 25 degrees Celsius, but is not temperature controlled). The mean bubble point is the pressure at which the ratio of the air flow of the wet membrane to the air flow of the dry membrane is 0.5.”
“Flow Time Test” is defined in the instant specification [0046] to mean: “To measure the flow time, isopropyl alcohol (IPA) is applied to the open side (larger pore size) of a 47 mm membrane disc at a pressure of 14.2 psi. If the pressure is different than 14.2 psi, the flow time is normalized to 14.2 psi. The time required to flow a certain volume of fluid through the membrane is measured and the time required to flow 500 mL is calculated.”
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 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.
Claims 1-2, 6-7, 22, 27 and 29 are rejected under 35 U.S.C. 103 as being unpatentable over US 2008/0020192 Al (hereinafter “Yen”) in view of US 2012/0061314 A1 (hereinafter “Choi”) and US 2008/0057389 Al (hereinafter “Kono”).
Regarding Claim 1-2 and 6-7 Yen discloses a porous polyethylene membrane comprises:
two or more layers, said layers have different average pore size, i.e. having a first side being a tight side and an opposing second side being an open side, wherein the open side has an average size of pores greater than an average size of pores of the tight side, (Abstract, [0036], [0038]); and
a thickness between the first and second sides (Examples 1-3, Table [0101]-[0115]),
wherein the thickness of the membrane may be from “about 20 microns to about 70 microns” [0085], and
wherein the mean bubble point is at greater than 100 psi (claim 23), and 140 psi or greater [0098].
Wherein the membrane may comprise two or more layers, wherein “individual layers or regions of the membrane can have a thickness that is about 50 percent or less of the total membrane thickness”, and including a specific example where there are two layers, one having larger pores is 45 micron thick, the other having smaller pores is 5 microns thick, [0085], and wherein, one of the two or more regions having different pore sizes has a thickness less than 20 percent of the total membrane thickness (claims 17 and 22). Thus it is obvious that the membrane may have two layers having different pore sizes, one of which is 50 percent or less, or 20 percent or less, of the total membrane thickness, and the other layer is the remainder of the membrane thickness; wherein the smaller membrane thickness layer may be the smaller pore size layer. Thus a tight side thickness of the first side is in a range from 50 percent or less and an open side thickness of the opposing second side is in a range from 50 percent or more of the thickness between the first side and the second side; this overlaps the range claimed.
Wherein “the difference in weight% polymer used to make adjacent layers should be maintained between about 0 weight % and about 10 weight %” [0086], it is not disclosed which side/layer may be the greater or smaller concentration and thus it would have been obvious to form either side using a greater or smaller concentration than the other side; and thus it is obvious to have a concentration of polyethylene in the solution forming the tight side be greater than a concentration of polyethylene in the solution forming the open side. It is noted that this is a product-by-process limitation, even though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process. See MPEP 2113.
Yen does not disclose (1) a log 10 flow time (seconds) relative to mean bubble point (pounds per square inch) that is less than a log 10 flow time relative to mean bubble point according to the equation: log 10(flow time)= 2.757 + 0.007105 * (mean bubble point) wherein: flow time is measured using the Flow Time Test, and mean bubble point is measured using the Mean Bubble Point Test; or (2) the thickness between the first side and the second side is in a range from 80 µm to 200 µm.
However, with regard to (1) IPA flow time, this is a measure of IPA permeability/flux of the membrane, where Yen discloses is obvious to adjust permeability and flux through at least choice of polymer, choice of porogen, cooling rates, and parameters during the extrusion and membrane forming process, [0063]-[0064], [0073], [0085], [0089], [0096], [0099] and where permeability and flux are known to effect what applications the membrane can be used for due to backpressure and filtration speed and are thus variables which achieve a recognized result. Thus the permeability and flux of the membrane are variables which achieve a recognized result, and the change in IPA flow time is merely optimization of the permeability or flux of the membrane.
Further Choi discloses a polyethylene/UPE microporous membrane wherein the IPA flow time may be 500 to 6500 seconds [0052].
It would therefore have been obvious for one of skill in the art to optimize IPA flow time through routine experimentation, including by using values including those disclosed by Choi and within the scope of the present claims, so as to produce desired filtration properties. See MPEP § 2144.05 (B).
This range of IPA flow time overlaps the range of less than the flow time equations as claimed. Since the range disclosed overlaps the range claimed, the range recited in the claim is considered prima facie obvious. Overlapping ranges are prima facie evidence of obviousness. It would have been obvious to one having ordinary skill in the art to have selected the portion of the disclosed range that corresponds to the claimed range. See MPEP 2144.05(I).
With regard to (2) the thickness, Kono discloses a similar multilayer, microporous polyolefin membrane formed from ultra-high-molecular-weight polyethylene (Abstract, [0012]), which may be formed via co-extrusion [0093], and which may have a thickness of from 3-200 µm [0111], and has layers with different thickness [0112].
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to modify the membrane of Yen in view of Choi by forming it to have a thickness of from 3-200 µm as disclosed by Kono because this is a known useful thickness range for similar co-extruded, multilayer UHMWPE membranes and thus this involves the simple substitution of known thickness ranges for similar co-extruded, multilayer UHMWPE membranes to obtain the predictable result of a functional membrane.
Regarding Claims 22 Yen in view of Choi and Kono discloses the porous polyethylene membrane of claim 1, wherein the thickness between the first side and the second side is in a range from 3-200 µm, supra.
Since the range disclosed overlaps the range claimed, the range recited in the claim is considered prima facie obvious. Overlapping ranges are prima facie evidence of obviousness. It would have been obvious to one having ordinary skill in the art to have selected the portion of the disclosed range that corresponds to the claimed range. See MPEP 2144.05(I).
Regarding Claim 27 Yen in view of Choi and Kono discloses the membrane of claim 1, wherein the first side comprises polyethylene having a first average molecular weight, the second side comprises polyethylene having a second average molecular weight, and the first molecular weight is equal to the second molecular weight; both sides are the same Yen UHMW-PE [0101]-[0109], and include polyethylene with a weight average molecular weight of 1 million and higher [0075]. Since the range disclosed overlaps the range claimed, the range recited in the claim is considered prima facie obvious. Overlapping ranges are prima facie evidence of obviousness. It would have been obvious to one having ordinary skill in the art to have selected the portion of the disclosed range that corresponds to the claimed range. See MPEP 2144.05(I).
Regarding Claim 29 Yen in view of Choi and Kono discloses the porous polyethylene membrane of claim 1, wherein the membrane is disclosed to have an IPA bubble point of 10 psi or greater, 100 psi or greater, Yen [0098], which inherently corresponds to pore sizes which overlap the range claimed. Further, this is expected, and obvious, for this to be the pore size of the smallest pores side of the membrane, i.e. the tight side, since they will be the most restrictive.
Overlapping ranges are prima facie evidence of obviousness. It would have been obvious to one having ordinary skill in the art to have selected the portion of the disclosed range that corresponds to the claimed range. See MPEP 2144.05(I).
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Yen in view of Choi and Kono further in view of US 2016/0096152 A1 (hereinafter “Ohno”).
Regarding Claim 8 Yen in view of Choi and Kono discloses the membrane of claim 1, which is used in filtration, Yen [0057], but no specific disclosure is given concerning the apparatus, and thus does not disclose its use in a filter cartridge as claimed.
However Ohno who discloses a similar polyolefin membrane, teaches that the membrane may be used in a filter housing that has fluid passed through it [0028]-[0029], [0046]-[0047], [0068].
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to use the membrane of Yen in view of Choi and Kono discloses in a filter cartridge having a housing as disclosed by Ohno as this is a known obvious means to effectively use the membrane for filtration. Where it would have been obvious and necessary that said housing have an inlet and an outlet for filtered fluid and the membrane supported within the housing between the inlet and the outlet such that liquid entering the inlet passes through the membrane before passing through the outlet i.e. to achieve continuous filtration.
Claims 1-2, 6-8, 22, 27 and 29 are rejected under 35 U.S.C. 103 as being unpatentable over US 2008/0020192 Al (hereinafter “Yen”) in view of US 2016/0096152 A1 (hereinafter “Ohno”) and Kono.
Regarding Claim 1-2 and 6-7 Yen discloses a porous polyethylene membrane comprises:
two or more layers, said layers have different average pore size, i.e. having a first side being a tight side and an opposing second side being an open side, wherein the open side has an average size of pores greater than an average size of pores of the tight side, (Abstract, [0036], [0038]); and
a thickness between the first and second sides (Examples 1-3, Table [0101]-[0115]),
wherein the thickness of the membrane may be from “about 20 microns to about 70 microns” [0085], and
wherein the mean bubble point is at greater than 100 psi (claim 23), and 140 psi or greater [0098].
Wherein the membrane may comprise two or more layers, wherein “individual layers or regions of the membrane can have a thickness that is about 50 percent or less of the total membrane thickness”, and including a specific example where there are two layers, one having larger pores is 45 micron thick, the other having smaller pores is 5 microns thick, [0085], and wherein, one of the two or more regions having different pore sizes has a thickness less than 20 percent of the total membrane thickness (claims 17 and 22). Thus it is obvious that the membrane may have two layers having different pore sizes, one of which is 50 percent or less, or 20 percent or less, of the total membrane thickness, and the other layer is the remainder of the membrane thickness; wherein the smaller membrane thickness layer may be the smaller pore size layer. Thus a tight side thickness of the first side is in a range from 50 percent or less and an open side thickness of the opposing second side is in a range from 50 percent or more of the thickness between the first side and the second side; this overlaps the range claimed.
Wherein “the difference in weight% polymer used to make adjacent layers should be maintained between about 0 weight % and about 10 weight %” [0086], it is not disclosed which side/layer may be the greater or smaller concentration and thus it would have been obvious to form either side using a greater or smaller concentration than the other side; and thus it is obvious to have a concentration of polyethylene in the solution forming the tight side be greater than a concentration of polyethylene in the solution forming the open side. It is noted that this is a product-by-process limitation, even though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process. See MPEP 2113.
Yen does not disclose (1) a log 10 flow time (seconds) relative to mean bubble point (pounds per square inch) that is less than a log 10 flow time relative to mean bubble point according to the equation: log 10(flow time)= 2.757 + 0.007105 * (mean bubble point) wherein: flow time is measured using the Flow Time Test, and mean bubble point is measured using the Mean Bubble Point Test; or (2) the thickness between the first side and the second side is in a range from 80 µm to 200 µm.
However, with regard to (1) IPA flow time, this is a measure of IPA permeability/flux of the membrane, where Yen discloses is obvious to adjust permeability and flux through at least choice of polymer, choice of porogen, cooling rates, and parameters during the extrusion and membrane forming process, [0063]-[0064], [0073], [0085], [0089], [0096], [0099] and where permeability and flux are known to effect what applications the membrane can be used for due to backpressure and filtration speed.
Further Ohno, who discloses a similar polyolefin membrane, teaches that the membrane bubble point and permeability (see as equivalent to the claimed flow time) are variables which are known to be adjusted, together and separately, to achieved desired filtration goals [0023]-[0025]. Ohno is seen to disclose generally that for similar polyolefin membranes, it is known to adjust the membrane bubble point and permeability/flow time because they effect particle collection and efficiency [0023]-[0025], and one would not be limited to the specific values given for the specific application on Ohno, as the application in Yen is not the limited to the same application, but would rather be motivated to try values ranging around and outside those disclosed in Yen, which would clearly including small deviations such as those that result in the membrane exhibiting the flow times claimed.
Thus the permeability and flux of the membrane are variables which achieve a recognized result, and it would therefore have been obvious for one of skill in the art to optimize this variable through routine experimentation, by using values including those within the scope of the present claims, so as to produce desired end results. See MPEP § 2144.05 (B).
With regard to (2) the thickness, Kono discloses a similar multilayer, microporous polyolefin membrane formed from ultra-high-molecular-weight polyethylene (Abstract, [0012]), which may be formed via co-extrusion [0093], and which may have a thickness of from 3-200 µm [0111], and has layers with different thickness [0112].
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to modify the membrane of Yen in view of Choi by forming it to have a thickness of from 3-200 µm as disclosed by Kono because this is a known useful thickness range for similar co-extruded, multilayer UHMWPE membranes and thus this involves the simple substitution of known thickness ranges for similar co-extruded, multilayer UHMWPE membranes to obtain the predictable result of a functional membrane.
Regarding Claim 8 Yen in view of Ohno and Kono discloses the membrane of claim 1, which is used in filtration, Yen [0057], but no specific disclosure is given concerning the apparatus, and thus does not disclose its use in a filter cartridge as claimed.
However Ohno who discloses a similar polyolefin membrane, teaches that the membrane may be used in a filter housing that has fluid passed through it [0028]-[0029], [0046]-[0047], [0068].
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to use the membrane of Yen in view of Ohno and Kono in a filter cartridge having a housing as disclosed by Ohno as this is a known obvious means to effectively use the mermen for filtration. Where is would have been obvious and necessary that said housing have an inlet and an outlet for filtered fluid and the membrane supported within the housing between the inlet and the outlet such that liquid entering the inlet passes through the membrane before passing through the outlet i.e. to achieve continuous filtration.
Regarding Claims 22 Yen in view of Ohno and Kono discloses the porous polyethylene membrane of claim 1, wherein the thickness between the first side and the second side is in a range from 3-200 µm, supra.
Since the range disclosed overlaps the range claimed, the range recited in the claim is considered prima facie obvious. Overlapping ranges are prima facie evidence of obviousness. It would have been obvious to one having ordinary skill in the art to have selected the portion of the disclosed range that corresponds to the claimed range. See MPEP 2144.05(I).
Regarding Claim 27 Yen in view of Ohno and Kono discloses the membrane of claim 1, wherein the first side comprises polyethylene having a first average molecular weight, the second side comprises polyethylene having a second average molecular weight, and the first molecular weight is equal to the second molecular weight; both sides are the same Yen UHMW-PE [0101]-[0109], and include polyethylene with a weight average molecular weight of 1 million and higher [0075]. Since the range disclosed overlaps the range claimed, the range recited in the claim is considered prima facie obvious. Overlapping ranges are prima facie evidence of obviousness. It would have been obvious to one having ordinary skill in the art to have selected the portion of the disclosed range that corresponds to the claimed range. See MPEP 2144.05(I).
Regarding Claim 29 Yen in view of Ohno and Kono discloses the porous polyethylene membrane of claim 1, wherein the membrane is disclosed to have an IPA bubble point of 10 psi or greater, 100 psi or greater, Yen [0098], which inherently corresponds to pore sizes which overlap the range claimed. Further, this is expected, and obvious, for this to be the pore size of the smallest pores side of the membrane, i.e. the tight side, since they will be the most restrictive.
Overlapping ranges are prima facie evidence of obviousness. It would have been obvious to one having ordinary skill in the art to have selected the portion of the disclosed range that corresponds to the claimed range. See MPEP 2144.05(I).
Response to Arguments
Applicant's arguments filed 12/02/2025 have been fully considered but they are not persuasive.
Regarding Applicants’ arguments directed toward the membrane thickness range of Yen, Choi and Ohno, these arguments are moot as Kono is now cited with regard to the membrane thickness.
Regarding Applicants’ arguments directed to the individual layer thicknesses, that Yen only discloses individual layers which have a thickness that is about 50 percent or less of the total membrane thickness; the Examiner disagrees. Yen discloses the membrane may comprise two or more layers, wherein “individual layers or regions of the membrane can have a thickness that is about 50 percent or less of the total membrane thickness”, and including a specific example where there are two layers, one is 45 micron thick, the other is 5 microns thick, [0085], and wherein, one of the two or more regions having different pore sizes has a thickness less than 20 percent of the total membrane thickness (claims 17 and 22). Thus it is obvious that the membrane may have two layers having different pore sizes, one of which is 50 percent or less, or 20 percent or less, of the total membrane thickness, and the other layer is the remainder of the membrane thickness.
Applicants’ request for Rejoinder will be held in abeyance until claims are found allowable.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Eric J. McCullough whose telephone number is (571)272-8885. The examiner can normally be reached Monday-Friday 10:00-6:00.
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/ERIC J MCCULLOUGH/ Examiner, Art Unit 1773
/BENJAMIN L LEBRON/ Supervisory Patent Examiner, Art Unit 1773