DETAILED ACTION
This action is in response to the remarks filed 10/24/2025, in which no claims have been amended, claims 1-10 are pending, claims 6-10 are withdrawn as directed to a non-elected invention and claims 1-5 are ready for examination.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
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 1-5 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 “island like microstructure” and “H-shaped ladder-like microstructure”. It is not clear how these terms are defined or differentiated, as they are not defined by the specification except as by the node size/shape and microfiber dimension as otherwise recited in the claims, including in the dependent claims. Thus the terms are not interpreted to add further structural limitation beyond the node size/shape and microfiber dimension as otherwise recited in the claims and that implied by the broadly defined shapes “island”, h” and “ladder”.
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 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 1 is rejected under 35 U.S.C. 102(a)(1) as being anticipated by US 4,248,924 (hereinafter “Okita’924”).
Regarding Claim 1 Okita’924 discloses a PTFE membrane (Abstract) having a “fiber structure including the length and thickness of the filaments in the porous polytetrafluoroethylene film and the state of the nodules linked by these filaments being unhomogeneous, wherein the fiber structure in the front surface is different from that in the back surface and, consequently, it provides films wherein the pore size in the front surface is different from that in the back surface, namely, asymmetric porous films”, C1/L37-44, and is thus seen to disclose a gradient pore structure (i.e. in a cross section), wherein a first porous outer surface has an island-like microstructure formed by a plurality of interconnected relatively-small nodes (as seen in Fig. 2, the nodes are generally circular and thus-island-like is a sea of fibers), and a second porous outer surface has an H-shaped ladder-like microstructure formed by a plurality of interconnected relatively-large nodes (as seen in Fig. 1, the larger nodes are oblong and generally parallel, connected by fibers and are thus “H-shaped ladder-like”), which , also see Figs. 1-2.
Claim 1 is rejected under 35 U.S.C. 102(a)(1) as being anticipated by US 4,234,535 (hereinafter “Okita’535”).
Regarding Claim 1 Okita’535 discloses a polytetrafluoroethylene (PTFE) membrane with larger pores on the outer surface (i.e. the second porous outer surface) and smaller pore on the inner surface (i.e. the first porous outer surface) (Abstract, C4/L60-66, i.e. a gradient pore structure, wherein a cross-section of the PTFE membrane has the gradient pore structure), and a first porous outer surface and a second porous outer surface of the PTFE membrane have fibers and nodes with different microstructures, the outer surface (the second porous outer surface) has ellipsoid nodes and inner surface (the first porous outer surface) has shorter (smaller) near spherical nodes (C3/L54-63) such that the first porous outer surface has an island-like microstructure formed by a plurality of interconnected relatively-small nodes (i.e. because the spherical nodes resemble islands in a sea of fibers), and the second porous outer surface has an H-shaped ladder-like microstructure formed by a plurality of interconnected relatively-large nodes (i.e. because of the ellipsoid nodes are oblong and generally parallel, connected by fibers and are thus “H-shaped ladder-like”); Figs. 4-8.
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.
Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Okita’535 in view of EP 0661336 A1 (hereinafter “Morishita”).
Regarding Claim 2 Okita’535 discloses the PTFE membrane with the gradient pore structure of claim 1, wherein each of the relatively-small nodes has a broadly circular structure (see Fig. 2), and while the nodes in Fig. 2 appear to be close to the size claimed they are not measured, and thus Okita’535 is silent to the diameters and thus does not disclose an average diameter of the relatively-small nodes is in a range of 0.30 μm to 1.50 μm.
However Morishita discloses a similar stretched PTFE membrane having a node/fibril structure wherein the nodes are disclosed to have an average diameter of not greater than that of a circle with a diameter of 1 micrometer (Abstract, P3/L43-45).
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to modify the PTFE membrane of Okita’535 by using a node diameter of not greater than that of a circle with a diameter of 1 micrometer for the circular (smaller) nodes as disclosed by Morishita because this involves the simple substitution of known circular node sizes in stretched PTFE membranes to obtain the predictable result of forming a successful PTFE membrane and because this range appears to be close to the smaller nodes disclosed by Okita’535 in Fig. 2.
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).
Claim 3 is rejected under 35 U.S.C. 103 as being unpatentable over Okita’535 in view of Morishita further in view of WO 2020131752 A1 (hereinafter “Suthar”).
Regarding Claim 3 Okita’535 discloses the PTFE membrane with the gradient pore structure of claim 2, wherein the relatively-small nodes are connected by a plurality of microfibers, having an average length of the short and thick microfibers is in a range of 0.1-10 micron (C3/L7-17) and are therefore “short”. Note: the term “short” is seen to be defined by the recited length range. Okita’535 is silent to the diameter and aspect ratio of the microfibers and thus does not disclose the microfibers have an average diameter of the microfibers is in a range of 0.05 μm to 0.2 μm, and an aspect ratio of the short and thick microfibers is in a range of 2 to 20.
However Suthar discloses a similar stretched PTFE membrane having a node/fibril structure wherein the fibrils (i.e. microfibers) have an average diameter in a range of 5-200 nm (0.05-0.2 micron), Abstract, P8/L4-7, Example 1.
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to modify the PTFE membrane of Okita’535 in view of Morishita by using a fiber diameter of 5-200 nm as disclosed by Morishita because this involves the simple substitution of known fibril diameters in stretched PTFE membranes to obtain the predictable result of forming a successful PTFE membrane.
This range of length and diameter results in an aspect ratio overlapping that claimed.
The microfibers are thus seen to be “short and thick microfibers”, where the terms “short” and “thick” are seen to be defined by the recited length and diameter ranges, respectively.
Since the range(s) disclosed overlaps the range(s) claimed, the range(s) recited in the claim is/are 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(s) that corresponds to the claimed range. See MPEP 2144.05(I).
Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over Okita’535 in view of CN 112717728 A (hereinafter “Lv”).
Regarding Claim 4 Okita’535 discloses the PTFE membrane with the gradient pore structure of claim 1, wherein each of the relatively-small nodes has a broadly elongated oval structure (see Fig. 2), and while the nodes in Fig. 1 appear to be close to the size claimed they are not measured, and thus Okita’535 is silent to the specific size and thus does not disclose wherein each of the relatively-large nodes has an average length of the relatively-large nodes is in a range of 0.5 μm to 10 μm, and an average width of the relatively-large nodes is in a range of 0.5 μm to 2 μm.
However Lv discloses a similar stretched PTFE membrane having a node/fibril structure wherein an average length of the nodes is in a range of 8-45 μm, and an average width of the nodes is in a range of 0.5-7 μm, in order to provide low pressure loss, high tensile strength and good mechanical properties; Abstract, Claim 2, pg. 3 para. starting “As a further development…”).
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to modify the PTFE membrane of Okita’535 by using for the relatively-large nodes an average length of the nodes in a range of 8-45 μm, and an average width of the nodes in a range of 0.5-7 μm, as disclosed by Morishita in order to provide low pressure loss, high tensile strength and good mechanical properties and because this range appears to be close to the larger nodes disclosed by Okita’535 in Fig. 1.
Since the range(s) disclosed overlaps the range(s) claimed, the range(s) recited in the claim is/are 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(s) that corresponds to the claimed range. See MPEP 2144.05(I).
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Okita’535 in view of Lv further in view of Suthar.
Regarding Claim 5 Okita’535 discloses the PTFE membrane with the gradient pore structure of claim 4, wherein the relatively-large nodes are connected by a plurality of microfibers, an average length of the microfibers is in a range of 1-100 μm (C3/L7-17) and they are therefore “long”. Note: the term “long” is seen to be defined by the recited length range.
Okita’535 is silent to the diameter and aspect ratio of the microfibers and thus does not disclose the microfibers having an average diameter of the long and thin microfibers is in a range of 5 nm to 200 nm, and an aspect ratio of the long and thin microfibers is in a range of 10 to 200.
However Suthar discloses a similar stretched PTFE membrane having a node/fibril structure wherein the fibrils (i.e. microfibers) have an average diameter in a range of 5-200 nm (0.05-0.2 micron), Abstract, P8/L4-7, Example 1.
Therefore, before the effective filing date, it would have been prima facie obvious to one of ordinary skill in the art to modify the PTFE membrane of Okita’535 in view of Lv by using a fiber diameter of 5-200 nm as disclosed by Morishita because this involves the simple substitution of known fibril diameters in stretched PTFE membranes to obtain the predictable result of forming a successful PTFE membrane.
This range of length and diameter results in an aspect ratio overlapping that claimed.
The microfibers are thus seen to be “long and thin microfibers”, where the terms “long” and “thin” are seen to be defined by the recited length and diameter ranges, respectively.
Since the range(s) disclosed overlaps the range(s) claimed, the range(s) recited in the claim is/are 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(s) that corresponds to the claimed range. See MPEP 2144.05(I).
Response to Arguments
Applicant's arguments filed 10/24/2025 have been fully considered but they are not persuasive.
In response to Applicants’ argument that the limitations “island like microstructure” and “H-shaped ladder-like microstructure” are not indefinite; the Examiner disagrees. While the Figures of the Application may be used to support amendments to the claims, the Figures cannot be read into the claims. The limitations of the claims do not make clear what the “island like microstructure” and “H-shaped ladder-like microstructure” are, besides that directly claimed, i.e. only to relative node size in claim 1. The differences seen in the Figures would suggest the H-like structure nodes have a higher degree of alignment over a longer distance than those of the “island-like” structure nodes and Applicant’s argue that ““H-shaped ladder-like microstructure" is a plurality of large elliptical nodes arranged in the shape of two vertical beams of a ladder … and a plurality of slender microfibers are connected between the two vertical beams”, however this is not claimed nor part of a special definition in the specification, and therefore the claim language needs to be amended to recite the more specific differences in structure. Thus the “island like microstructure” and “H-shaped ladder-like microstructure” terms/limitations are indefinite and are not interpreted to add further structural limitation beyond the node size/shape and microfiber dimension as otherwise recited in the claims and that implied by the broadly defined shapes “island”, h” and “ladder”.
In response to Applicants’ arguments directed to the production method of the PTFE membranes; the claims are to an apparatus (i.e. a membrane) whose method of production is not limited, and therefore arguments to the differences in the method of producing the prior art membrane(s) vs that of the instant disclosure are not persuasive against the rejections, which do not address the method of production.
In response to Applicants’ argument that Okita’924 does not disclose “island like microstructure” and “H-shaped ladder-like microstructure”; the Examiner disagrees. Applicants’ argue “Figure 1 of Okita'924, the node shape is unclear and the distribution is irregular. In Figure 2 of Okita'924, no nodes are even visible”. However it is first noted that the disclosure is not limited to the figures and their specific nodule and filament structures shown (C3/L28-45), but with regard to the figures, they are seen to show:
H-like microstructure, back surface: “the nodules in the back surface shown in FIG. 1 become long and slender independently, and the longer axis of the nodule is oriented perpendicularly to the stretching direction” – thus describing long, slender independent nodes which are seen in Fig. 1, and create the “H-like structure” – i.e. large nodes perpendicular to fibers.
Island-like, microstructure, front surface: “shown in FIG. 2, independent nodules are not observed, and the nodules are linked to one another such that the whole surface appears as if it were a mat” – while Fig. 2 is low quality, it appears to shown smaller nodes connected by smaller fibers to create a more regular mat-like appearance, and is specifically described to comprise nodules connected by filaments, where any nodes connected by filaments would broadly be “island like”, where the fibers are the “water” between the “island” nodes/nodules. Thus Okita’924 is seen to disclose the “island like microstructure” and “H-shaped ladder-like microstructure” as claimed.
In response to Applicants’ argument that the membrane of the instant disclosure possesses beneficial properties not provided by the prior art membrane, the data provided in the instant disclosure are not sufficient to show unexpected results of the claimed invention. Specifically:
It is well settled that evidence presented to rebut a prima facie case of obviousness must be commensurate in scope with the claims to which it pertains and that such evidence which is considerably narrower in scope than claimed subject matter is not sufficient to rebut a prima facie case of obviousness. See 2145 and 716.02(d) which states “[w]hether the unexpected results are the result of unexpectedly improved results or a property not taught by the prior art, the "objective evidence of nonobviousness must be commensurate in scope with the claims which the evidence is offered to support." In other words, the showing of unexpected results must be reviewed to see if the results occur over the entire claimed range” and “[t]o establish unexpected results over a claimed range, applicants should compare a sufficient number of tests both inside and outside the claimed range to show the criticality of the claimed range”.
As rejected claim 1 is significantly broader than examples in specification, which show specific nodule and filament structure, sizes and lengths which are not recited in the claims, and thus the evidentiary showing is far from being commensurate in scope with the degree of patent protection sought. Thus, at least for this reason, the claimed invention is not seen to possess unexpected results and is obvious in view of the cited art.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/ERIC J MCCULLOUGH/ Examiner, Art Unit 1773
/JOSEPH W DRODGE/ Primary Examiner, Art Unit 1773