DETAILED ACTION
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 .
StatusClaims(s) 18-35, is/are filed on 9/10/2026 are currently pending. Claim(s) 28-35 is/are withdrawn without traverse, 18-27 is/are rejected.
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.
Claim(s) 25 is/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 regards as the invention.
Claim 25 recites a film “having a Shore hardness of 30 or more and 50 or less” but does not identify the durometer scale (i.e. Shore A or Shore D) as different Shore scales give different readings for the same material. No support appears to be found in the specification therefore the claim is indefinite.
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 pre-AIA 35 U.S.C. 103(a) which forms the basis for all obviousness rejections set forth in this Office action:
(a) A patent may not be obtained though the invention is not identically disclosed or described as set forth in section 102 of this title, if the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter pertains. Patentability shall not be negatived by the manner in which the invention was made.
The factual inquiries set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied for establishing a background for determining obviousness under pre-AIA 35 U.S.C. 103(a) 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) 18-23, 25-27 is/are rejected under 35 U.S.C. 103 as being unpatentable over Keaney (US 20200268960 A1) in view of Li (US 20170173501 A1).
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Regarding claim 18, Keaney discloses a filter (filter membrane 212) having a plurality of filter pores (pores 214) penetrating one surface (second major surface 215) and another surface (first major surface 213) of the filter (Keaney [0048]: the pores 214 run through the thickness of membrane 212, from major surface 213 to major surface 215), wherein the filter pore (214) has a first opening (narrow end, nominal diameter d2) on the one surface (215) and a second opening (wide end, entrance diameter d1) on the another surface (213) (Keaney [0053]: the nominal diameter d2 is on the permeate side and the larger entrance diameter d1 is on the retentate side; [0014]–[0015]: FIGS. 3B and 3C show the wide end and the narrow end of the tapered round pores), a ratio (L1/W1) of a major axis diameter L1 to a minor axis diameter W1 of the first opening is 1.00 or more and 1.20 or less (Keaney [0051]: the pores can be round with a nominal diameter d2. For a round opening L1 = W1, so L1/W1 = 1.00), the minor axis diameter W1 is 7.0 μm or more and 9.0 μm or less (Keaney [0027]: "a nominal diameter of 6 um, 7 um, or 8 um". The 7 μm and 8 μm values fall within the claimed range; see also the 4–8 μm range at [0051]; MPEP 2131.03), a ratio (L2/W2) of a major axis diameter L2 to a minor axis diameter W2 of the second opening is 1.00 or more and 1.20 or less (Keaney [0014]: FIG. 3B shows that the wide end of each tapered pore is also round, so L2/W2 = 1.00).
Keaney does not disclose a ratio (W2/W1) of the minor axis diameter W2 to the minor axis diameter W1 and a ratio (L2/L1) of the major axis diameter L2 to the major axis diameter L1 are both 1.20 or more and 1.50 or less. Keaney does however give the dimensions that set these ratios. According to [0053], the membrane thickness t is 1–50 μm, and the taper angle θ, measured from the central axis 220 of pore 214, is 11°±3° (for example 11.31°). For a pore that tapers evenly around its axis, d1 = d2 + 2t·tanθ. This gives the following ratios: With d2 = 8 μm, t = 10 μm and θ = 11.31°, d1 = 12 μm and W2/W1 = 1.50. With d2 = 7 μm, t = 10 μm and θ = 8°, W2/W1 is about 1.40. Because both openings are round, L2/L1 equals W2/W1. Keaney's disclosed ranges therefore overlap the claimed range, which establishes a prima facie case of obviousness (MPEP 2144.05(I)).
Alternatively, Li also teaches this feature directly. Li is analogous art as it concerns filtration through perforated sheets with laser-formed tapered pores, and it addresses the same problem of pores becoming blocked. Li discloses a filter sheet (sheet 40) with laser-drilled conical pores (pores 44). Each pore has a larger opening (46) on one surface (outer surface 24) and a smaller opening (54) on the other surface (inner surface 22). According to Li [0069], the ratio of the larger opening to the smaller opening is "from about 1.1 to about 4:1, or from about 1.4:1 to about 3:1". It would have been obvious to one of ordinary skill in the art before the effective filing date to give Keaney's tapered pores an opening ratio in the range taught by Li, such as 1.2 to 1.5 to improve catching solids more efficiently without weaking the structure – Li [0069-0070]. Additionally, both references treat the taper as a design choice that involves trade-offs. The opening ratio is therefore a result-effective variable, and finding a workable range for it is routine optimization (MPEP 2144.05(II)).
Regarding claim 19, Keaney teaches having a thickness of 10 μm or more and 30 μm or less. Keaney [0053] and [0089] disclose a membrane thickness of 1–50 μm, which overlaps the claimed range. Keaney [0053] also allows the taper to extend only partway through the film, leaving a straight section of 1–10 μm at the narrow end, so a film in the claimed thickness range can keep the ratios of claim 18. See also Li [0068], which teaches a pore thickness starting at about 10 microns.
Regarding claim 20, Keaney teaches wherein a distance between a center of gravity C2 of the second opening and an intersection point C2′ between the another surface and a perpendicular line drawn from a center of gravity C1 of the first opening to the another surface is 3 μm or less. Keaney [0053] measures the taper angle from the central axis 220 of pore 214, and [0028] shows that this axis is perpendicular to the major surface. Centers C1 and C2 therefore both lie on axis 220, so C2 sits at C2′ and the distance is about 0 μm.
Regarding claim 21, Keaney teaches having a porosity rate of 10.5% or more and 25% or less. Keaney [0154] discloses an open area of 5 to 15 percent, or 8 to 12 percent, which overlaps the claimed range. For example, 8 μm pores on the 20 μm spacing of [0054] in a square array give an open area of about 12.6%. Li [0067] also caps hole voidage at 25%. MPEP 2144.05(I).
Regarding claim 22, Keaney teaches the plurality of filter pores (pores 214) are arranged at equal intervals. Keaney [0027] discloses pores that are uniformly sized and uniformly spaced, within 10%. Keaney [0013] describes FIG. 3A as a uniform array of tapered pores. See also Li [0058], which teaches pores 44 spaced at equal distances from one another.
Regarding claim 23, Keaney in view of Li teaches wherein an interval between the filter pores (pores 214) is 8 μm or more and 30 μm or less. Keaney [0054] discloses a pore spacing of 20–30 μm, or 23–27 μm, with examples made at 25 μm.
Regarding claim 25, Keaney teaches being a filter comprising a film in which the filter pores are provided. The film having a Shore hardness of 30 or more and 50 or less and a Young's modulus of 5 MPa or more and 25 MPa or less would be inherent as it teaches the same material i.e. polyethylene and similar process of making as the application.
Regarding claim 26, Keaney teaches the filter comprising a thermoplastic resin. Keaney [0052] discloses that filter membrane 212 can be made from a polyimide, polyethylene terephthalate, or polycarbonate film. PET and polycarbonate are thermoplastic resins.
Regarding claim 27, Keaney [0052] teaches wherein a main component of the thermoplastic resin is a polyethylene or a polypropylene.
Claim(s) 24 is/are rejected under 35 U.S.C. 103 as being unpatentable over Keaney (US 20200268960 A1) in view of Li (US 20170173501 A1), Kihara "Low-autofluorescence fluoropolymer membrane filters for cell filtration," Jpn. J. Appl. Phys. 57, 06JF03 (2018) and Tang, “Microfluidic device with integrated microfilter of conical-shaped holes for high efficiency and high purity capture of circulating tumor cells” Sci. Rep. 4, 6052 (2014).
Regarding claim 24, Keaney in view of Li teaches: a filter comprising a film (filter membrane 212) in which the filter pores (pores 214) are provided (Keaney [0052]: the membrane is a polymer film). It does not teach the film having a total light transmittance of 80% or more. However, Kihara teaches an optically transparent ETFE membrane filter with through-holes, used to capture circulating tumor cells in blood for fluorescence detection. Kihara (Introduction) reports that 25 µm ETFE film has a transmittance of "approximately 90% at a wavelength of 400 nm." Also see at least Tang (Introduction) states that CTC filters should be "optically transparent and biologically compatible" so that the captured cells can be analyzed afterward. It would have been obvious to one of ordinary skill in the art before the effective filing date to make Keaney's filter film with a total light transmittance of 80% or more, as taught by Kihara and Tang. A transparent film lets captured cells be viewed and analyzed right on the filter as Keaney [0040] itself contemplates collecting the captured CTCs for further analysis.
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It is noted that any citations to specific, pages, columns, lines, or figures in the prior art references and any interpretation of the reference should not be considered to be limiting in any way. A reference is relevant for all it contains and may be relied upon for all that it would have reasonably suggested to one having ordinary skill in the art. See MPEP 2123.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Waqaas Ali whose telephone number is (571) 270-0235. The examiner can normally be reached on M-F 9-5 PM.
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/WAQAAS ALI/Primary Examiner, Art Unit 1777
