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 .
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.
Claims 1, 5–7, and 9–12 are rejected under 35 U.S.C. 103 as being unpatentable over Yegya-Raman et al., US 2021/0370208 A1 in view of Wertz et al., US 2011/0259813 A1 and in further view of Suzuki et al., JP 2013094717 A1.
Regarding claims 1, 7, and 9, Yegya-Raman teaches a filter media that can be used for air filtration, which reads on the claimed “air filter medium.” See Yegya-Raman [0019]. The filter media comprises:
A porous additional layer, which is a porous resin membrane because it can be made from a meltblown material. See Yegya-Raman [0093], [0138].
A support layer that is formed of a fibrous material including glass fibers (the claimed “collection layer”) with a diameter ranging 0.15 to 30 microns (overlapping with the claimed range of 0.2 to 2.0 microns). See Yegya-Raman [0093], [0071].
An air-permeable adhesive layer with a basis weight of 0.05 to 10 gsm (g/m2). See Yegya-Raman [0109], [0127]–[0128].
The support layer, adhesive layer, and additional layer are placed in this order from upstream to downstream of the filter media configured to allow an air flow to pass through the filter media, as claimed. This is because the support layer (e.g., second layer 120) can be positioned upstream of first layer 110 with first layer 110 being upstream of additional layer (e.g., 130). See Yegya-Raman Fig. 1B, [0024], [0137].
An initial pressure drop of the filter media at a permeate flow rate of 0.67 cm/s is 0.01 to 80 kPa (10 to 80,000 Pa), which either overlaps with or is close enough to the claimed range of 250 Pa or less at a permeate flow rate of 5.3 cm/s, to establish a prima facie case of obviousness. See Yegya-Raman [0093].
Yegya-Raman differs from claim 1 because it fails to teach the additional layer comprising a fluorine resin (claim 1) with the additional layer being a polytetrafluoroethylene membrane (claim 7), as claimed. But Yegya-Raman teaches that the additional layer can be a meltblown layer manufactured from synthetic fibers of some, unspecified polymer material. See Yegya-Raman [0138]. With this in mind, Wertz teaches a filter media comprising a meltblown layer that is manufactured from a list of polymers including PTFE (polytetrafluoroethylene). See Wertz [0083]. It would have been obvious to use PTFE as the polymer of the additional (meltblown) layer of Yegya-Raman because this would merely represent the selection of a known material based on the suitability of its intended use. See MPEP 2144.07.
Yegya-Raman also differs from claim 1 because it is silent as to the adhesive layer being a fibrous adhesive that contains fibers having an average fiber diameter of 10 to 30 µm with the adhesive layer also having a thickness of 5.5 to 16 µm, as claimed.
But Suzuki teaches an air filter media comprising an adhesive layer 20 that attaches a pre-filter layer 30 to a fiber layer 12. See Suzuki Fig. 2, [0048]. The adhesive layer 20 comprises two adhesive layers: a first adhesive layer 21 (attached to the fiber layer 12) and a second adhesive layer 22 (attached to the pre-filter layer 30). Id. Each adhesive layer 21, 22 can have a basis weight of 5 g/m2, a thickness of 15 µm, and an average fiber diameter of 10 to 60 µm. Id. at [0045], [0061]. The adhesive layer 20 is beneficial because it makes clogging less likely to occur between the filter layers. Id. at [0043].
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It would have been obvious to use the adhesive layer 20 of Suzuki as the adhesive layer of Yegya-Raman to reduce the likelihood of clogging between the layers of the filter media.
With this modification one of the two layers 21, 22 of the adhesive layer 20 of Suzuki reads on the claimed “air-permeable adhesive layer.” The layer 21 or 22 has a basis weight of 5 g/m2 (within the claimed range of 4 to 6 g/m2), a thickness of 15 µm (within the claimed range of 5.5 to 16 µm) and fibers having an average fiber diameter of 10 to 60 µm (overlapping with the claimed range of 10 to 30 µm).
The filter media of Yegya-Raman as modified is presumed to exhibit the following properties because the filter media has substantially the same structure as claimed. See MPEP 2112.01, subsection I (when the structure recited in the reference is substantially identical to that of the claims, claimed properties or functions are presumed to be inherent).
“when a test is performed in which polyalphaolefin particles are allowed to pass through the air filter medium at a concentration of 0.2 to 0.5 g/m2 and a linear velocity of 5.3 cm/sec and a holding amount of the polyalphaolefin particles held by the air filter medium and a variation of a pressure drop of the air filter medium are evaluated, the holding amount is 43.0 g/m2 or more from a moment when the holding amount reaches 20 g/m2 to a moment when the pressure drop of the air filter medium reaches PD1 + 120 Pa, where PD1 is the pressure drop of the air filter medium at the moment when the holding amount reaches 20 g/m2, the polyalphaolefin particles being polydisperse particles having a peak in number in a particle size range of 0.1 to 0.2 um” (claim 1)
“wherein when the test is performed, the holding amount is 50 g/m2 or more from when the pressure drop of the air filter medium is an initial value PD0 to when the pressure drop of the air filter medium reaches PD0 + 250 Pa” (claim 9)
Note also that the filter media has a dust holding capacity of up to 400 g/m2. See Yegya-Raman [0102].
Regarding claim 5, Yegya-Raman teaches a fine fiber layer (e.g., first layer 110) (the claimed “first air-permeable supporting layer”) (capable of providing support as it is a layer of material) with the fine fiber layer being placed between “air-permeable adhesive layer” (adhesive layer 21 or 22 between support layer, e.g., 120, and additional layer, e.g., 130) and the “porous fluorine resin membrane” (additional layer, e.g., 130). See Yegya-Raman [0093], [0137].
Regarding claim 6, Yegya-Raman teaches that another additional layer (fourth layer) can be positioned adjacent to fine fiber layer (e.g., first layer 120), resulting in the fourth layer being positioned downstream of the additional layer (the additional layer is the “porous fluorine resin membrane”). See Yegya-Raman Fig. 1B, [0138]. The fourth layer reads on the claimed “second air-permeable supporting layer placed on a downstream side in a direction of the air flow with respect to the porous fluorine resin membrane.”
Regarding claim 10, Yegya-Raman teaches that the filter media can be pleated. See Yegya-Raman [0134]. This reads on a “filter pleat pack comprising an air filter medium folded into pleats, wherein the air filter medium is the air filter medium according to claim 1,” as claimed.
Regarding claims 11 and 12, Yegya-Raman teaches that the filter media can be incorporated into a filter element. See Yegya-Raman [0137]. The filter element reads on the “air filter unit comprising an air filter medium, wherein the air filter medium is the air filter medium according to” claims 1 or 10, as claimed.
Response to Arguments
Applicant’s arguments with respect to claims 1, 5–7, and 9–12 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
The Applicant argues that there is no factual evidence that the air filter medium of the prior art has the properties described in the last limitation of claim 1 (starting with “when a test is performed”). See Applicant Rem. filed May 28, 2026 (“Applicant Rem.”) 7. The Examiner respectfully disagrees. The prior art cited above is presumed to have this claimed property because it has substantially the same structure as the claimed air filter medium. See MPEP 2112.01, subsection I (when the structure recited in the reference is substantially identical to that of the claims, claimed properties or functions are presumed to be inherent). Note that when PTO has a sound basis for believing that the products of the applicant and the prior art are the same (as here), the Applicant has the burden of showing that they are not.
Also, note that the filter media of Yegya-Raman has a relatively high dust holding capacity of up to 500 g/m2. See Yegya-Raman [0102]. Therefore, while the reference is silent as to the filter media being tested in the claimed manner, the filter media is presumed to exhibit the claimed below, due to the high dust holding capacity of up to 500 g/m2:
“when a test is performed in which polyalphaolefin particles are allowed to pass through the air filter medium at a concentration of 0.2 to 0.5 g/m2 and a linear velocity of 5.3 cm/sec and a holding amount of the polyalphaolefin particles held by the air filter medium and a variation of a pressure drop of the air filter medium are evaluated, the holding amount is 43.0 g/m2 or more from a moment when the holding amount reaches 20 g/m2 to a moment when the pressure drop of the air filter medium reaches PD1 + 120 Pa, where PD1 is the pressure drop of the air filter medium at the moment when the holding amount reaches 20 g/m2, the polyalphaolefin particles being polydisperse particles having a peak in number in a particle size range of 0.1 to 0.2 µm.”
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to T. BENNETT MCKENZIE whose telephone number is (571)270-5327. The examiner can normally be reached Mon-Thurs 7:30AM-6:00PM.
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T. BENNETT MCKENZIE
Primary Examiner
Art Unit 1776
/T. BENNETT MCKENZIE/Primary Examiner, Art Unit 1776
1 Suzuki is in the record as the 42-page Foreign Reference filed April 18, 2023.
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