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 .
Response to Amendment
This is a final office action in response to Applicant’s remarks and amendments filed on 03/12/2026. Claims 1, 2, 10, and 11 are currently amended. Claims 2, 9-11,13, 15-18, and 20 remain withdrawn. Claims 1, 4, 6-8, and 19 are presented for examination.
The 35 U.S.C. § 103 rejections in the previous office action are maintained.
Response to Arguments
Applicant's arguments filed 03/12/2026 have been fully considered but they are not persuasive.
Applicant argues the claimed ionic material content of more than 0 µmol/g and 22.5 µmol/g or less per unit mass of the separator required by amended claim 1 is nonobvious over the cited art. As demonstrated in the Examples of the instant disclosure, the separator of the claimed invention exhibits excellent viscosity suppression when the ionic material is present in an amount within the claimed range. This effect would not have been obvious to a person skilled in the art. In addition, Yoshitomi teaches away from the claimed range by disclosing in [0014] that when the calcium content is less than 1000 ppm (equivalent to an ionic material content of less than 25 µmol/g), hydrogen fluoride is not sufficiently supplemented.
Examiner respectfully disagrees. In response to applicant's argument that the prior art does not recognize the role of the ionic material in suppressing viscosity, the fact that the inventor has recognized another advantage which would flow naturally from following the suggestion of the prior art cannot be the basis for patentability when the differences would otherwise be obvious. See Ex parte Obiaya, 227 USPQ 58, 60 (Bd. Pat. App. & Inter. 1985).
The lower end of the content of the ionic material disclosed by Yoshitomi (1000 ppm or 25 µmol/g) is so mathematically close to the claimed higher end of the range of ionic material content (22.5 µmol/g) that the difference between the claimed range is virtually negligible absent any showing of unexpected results or criticality ([MPEP 2144.05(I)]). The Examples in the instant specification do not demonstrate the criticality of the claimed range because Table 1 shows the relative viscosity of the coating liquid appears to depend on factors other than the content of ionic material (Comparative Example 1 and Example 5, e.g., both include ionic material in the amount of 2.5 µmol/g and have different relative viscosities). Therefore, it would have been obvious to one of ordinary skill in the art to arrive at the claimed range, without undue experimentation, to arrive at the claimed range to achieve an optimized balance between gas reduction and cycle characteristics as taught by Yoshitomi and set forth in the below rejection of claim 1.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1, 4, 6, 8, and 19 are rejected under 35 U.S.C. 103 as being unpatentable over Kasamatsu (US 2021/0020889 A1; previously cited) in view of Yoshitomi (JP-2011216318-A, cited in the IDS filed 10/08/2021; the rejections below refer to the machine translation mailed 12/12/2025).
Regarding claim 1, Kasamatsu discloses a separator (13, Figure 1, [0012]) for a non-aqueous secondary battery (10, Figure 1, [0012]), the separator (13) comprising: a porous substrate (13a, Figure 1, [0031]); and a heat-resistant porous layer (13b, Figure 1, [0032]) that is formed on one side or on both sides of the porous substrate (13a) ([0032]), and that contains a wholly aromatic polyamide (polymetaphenylene isophthalamide, [0054]) and inorganic particles ([0033]), and wherein an average primary particle diameter of the inorganic particles is from 0.03 µm to less than 0.1 µm (overlapping range of 0.05 µm to 2 µm, [0044], establishes a prima facie case of obviousness [MPEP § 2144.05(I)]).
Kasamatsu does not disclose wherein the heat-resistant porous layer contains an ionic material, and wherein the ionic material is one or more selected from the group consisting of a metal nitrate, a metal chloride, a metal chlorate, a metal bromide, a metal iodide, a metal iodate, and a metal perchlorate, and wherein a content of the ionic material is more than 0 µmol/g and 25 µmol/g or less per unit mass of the separator for a nonaqueous secondary battery.
Yoshitomi teaches a separator for a non-aqueous secondary battery ([0001]), the separator comprising: a porous substrate (polyolefin porous substrate, [0009]); and a heat-resistant porous layer that is formed on one side or on both sides of the porous substrate ([0009]), and that contains a wholly aromatic polyamide ([0009]), inorganic particles ([0009]) and an ionic material (inorganic salt of calcium, [0015]; calcium chloride is added to the coagulation bath, [0047], and therefore present in the heat-resistant porous layer because the coagulation slurry is used to form the heat-resistant porous layer, [0031]), wherein the ionic material is a metal chloride (calcium chloride, [0015]), and wherein a content of the ionic material (calcium content) is more than 1000 g/g and less than 2000 g/g per unit mass of the separator and that the content is related to battery life and cycle performance ([0013]-[0014]; the disclosed range is equivalent to a range of 25 µmol/g – 50 µmol/g of calcium chloride per unit mass of the separator).
A person having ordinary skill in the art before the effective filing date of the invention would find it obvious to add an ionic material (inorganic salt of calcium) to the heat-resistant porous layer of Kasamatsu because Yoshitomi teaches that doing so improves battery life by reducing side reactions and gas generation in the battery ([0013]) and to optimize the content of the ionic material in the heat-resistant porous layer to an amount corresponding to more than 0 µmol/g and 22.5 µmol/g or less per unit mass of the separator for a nonaqueous secondary battery because Yoshitomi teaches that the calcium content should be high enough to prevent gas generation but not so high as to deteriorate the cycle characteristics of the battery ([0014]).
Regarding claim 4, Kasamatsu in view of Yoshitomi teaches wherein the inorganic particles are barium sulfate (Kasamatsu: [0044]-[0045]).
Regarding claim 6, Kasamatsu in view of Yoshitomi teaches wherein the wholly aromatic polyamide is a meta-wholly aromatic polyamide (Kasamatsu: polymetaphenylene isophthalamide, [0054]).
Regarding claim 8, Kasamatsu in view of Yoshitomi does not disclose wherein a mass per unit area of the heat-resistant porous layer is from 1.0 g/m2 to 30.0 g/m2.
However, Yoshitomi teaches that a mass per unit area of the heat-resistant porous layer is preferably about 2 to 10 g/m2 ([0023]). A person having ordinary skill in the art before the effective filing date of the invention would have found it obvious to have formed the heat-resistant porous layer of Kasamatsu in view of Yoshitomi to have a mass per unit area of 2 to 10 g/m2 because Yoshitomi teaches that such a configuration is preferable ([0023]).
Regarding claim 19, Kasamatsu in view of Yoshitomi teaches wherein the non-aqueous secondary battery is a lithium ion secondary battery (Kasamatsu: lithium salt in electrolyte and electrode assembly designed to prevent deposition of lithium, [0013]-[0014]).
Claim 7 is rejected under 35 U.S.C. 103 as being unpatentable over Kasamatsu (US 2021/0020889 A1) in view of Yoshitomi (JP-2011216318-A), as applied to claim 1 above, and further in view of Shinohara (US 2012/0251868 A1).
Regarding claim 7, Kasamatsu in view of Yoshitomi does not disclose wherein a content ratio of the inorganic particles in the heat-resistant porous layer is 30% by volume to 95% by volume with respect to a total amount of the wholly aromatic polyamide and the inorganic particles.
Shinohara teaches a separator (laminated film, [0001]) for a non-aqueous secondary battery ([0001]), the separator comprising: a porous substrate (porous film, [0019]); and a heat-resistant porous layer ([0019]) that is formed on one side or on both sides of the porous substrate ([0019]), and that contains a polymer ([0047]) and inorganic particles (filler, [0044]), wherein an average primary particle diameter of the inorganic particles is from 0.03 µm to less than 0.1 µm (overlapping range of 0.01 µm to 0.5 µm, [0046]) and wherein a content ratio of the inorganic particles in the heat-resistant porous layer is 30% by volume to 95% by volume with respect to a total amount of the polymer and the inorganic particles (overlapping range of not less than 20% by volume to less than 100% by volume, [0049]). A person having ordinary skill in the art before the effective filing date of the invention would find it obvious to have modified the separator of Kasamatsu in view of Yoshitomi such that a content ratio of the inorganic particles in the heat-resistant porous layer is 30% by volume to 95% by volume with respect to a total amount of the wholly aromatic polyamide and the inorganic particles because Shinohara teaches that such a configuration is known in the art and allows for adequate ion permeability ([0049]).
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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/C.C.D./Examiner, Art Unit 1723 /TIFFANY LEGETTE/Supervisory Patent Examiner, Art Unit 1723
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