SEPARATOR FOR POWER STORAGE DEVICE, AND POWER STORAGE DEVICE
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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 6/9/2026 has been entered.
Response to Amendment
In response to communication filed on 6/9/2026:
Claim 1 has been amended; claims 21-28 have been canceled. No new matter has been entered.
Previous rejections under 35 USC 103 have been upheld.
Response to Arguments
Applicant's arguments filed 5/1/2026 have been fully considered but they are not persuasive.
The Applicant discloses: “Amended claim 1 now specifies: "a melt flow rate (MFR) of the microporous layer (X) at a load of 2.16 kg and a temperature of 230 °C is 0.35 g/10 min or more and 0.6 g/10 min or less" and "in an MD-TD surface observation of the microporous layer (X) by a scanning electron microscope (SEM), an average long pore diameter of pores present in the microporous layer (X) is 100 nm or more and 300 nm or less and a maximum long pore diameter of pores present in the microporous layer (X) is 220 nm or more and 400 nm or less" (see lines 4 and 7 of amended claim 1).
The Examiner asserts that in order to demonstrate criticality of one variable, all others need to be constant with each other. See Office Action at Section No. 11. Here, as demonstrated by Tables 1 and 4 of the specification, among Examples 1 and 5 and Comparative 3 to 7 - all of which share identical values for MFR of the microporous layer (X), density of the polypropylene (PP), weight average molecular weight (Mw) of PP, molecular weight distribution (Mw/Mn) of PP, pentad fraction of PP, and melt tension of microporous layer (X) - only Example 1 satisfies both the requirement that the average long pore diameter of pores present in the microporous layer (X) is 100 nm or more and 300 nm or less; and the maximum long pore diameter of pores present in the microporous layer (X) is 220 nm or more and 400 nm or less.
In other words, both the average long pore diameter (100 nm or more and 300 nm or less), and the maximum long pore diameter (220 nm or more and 400 nm or less) are specifically limited in claim 1 as amended. The benefit of the claimed invention according to amended claim 1 is further supported by the Example section of the specification. As shown in the following table derived from Tables 1 and 4, Example 1 (which is the only Example in the table satisfying both the claimed average long pore diameter and the claimed maximum long pore diameter) exhibits superior puncture strength, superior cycle capacity retention rate, and an absence of clogging after cycling.
In contrast, Example 5, which satisfies the average long pore diameter limitation but not the maximum diameter limitation, exhibits inferior puncture strength (309 gf vs. 323 gf for Example 1). Furthermore, Comparative Examples 3-7, which satisfy the maximum long pore diameter limitation but not the average diameter limitation, universally exhibit inferior cycle capacity retention rates and clogging after cycling. Accordingly, amended claim 1 is specifically supported by a controlled, single-variable comparison that demonstrates the criticality of both average long pore diameter and maximum long pore diameter in combination with the claimed MFR and pentad fraction.”
The Examiner respectfully traverses. Example 5 shows a puncture strength within the 5% error margin despite the maximum long pore diameter being outside the claimed range. Further, Examples 6 and 9 disclose parameters identical to Example 1 except for a maximum long pore diameter showing puncture strength values equal to or better than Example 1. Therefore, displaying criticality has not been established due to lack of consistency.
Further, the Applicant is establishing criticality for the claimed ranges by using only one example (Example 1). This is not enough data to establish criticality. MPEP 716.02(d) II states to 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. In re Hill, 284 F.2d 955, 128 USPQ 197 (CCPA 1960). This has yet to be shown.
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 (i.e., changing from AIA to pre-AIA ) 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, 5, 7-8, 10, 14, and 17-20 are rejected under 35 U.S.C. 103 as being unpatentable over Hamasaki et al. (WO 2019/103947 A1 using US 2021/0367309 A as an English language translation.) and further in view Nemoto et al. (US 2013/0196208 A1).
Regarding claims 1, 19, and 20, Hamasaki et al. teach an electricity storage device separator comprising a microporous layer (X) mainly composed of a polyolefin (A) (Abstract; paragraph 0062 discloses a separator for an electric storage device comprising a microporous membrane comprising polyolefin. Further, claim 1 discloses the polyolefin is comprised of polypropylene.),
wherein a melt flow rate (MFR) of the microporous layer (X) at a load of 2.16 kg and a temperature of 230 °C is 0.35 g/10 min or more and 0.6 g/10min or less (Paragraph 0141 discloses determining melt flow rate at a load of 2.16 kg and a temperature of 230 °C. Claim 1 discloses a melt flow rate of 1.0 g/10 min or less.), and
in an MD-TD surface observation or an ND-MD cross-section observation of the microporous layer (X) by a scanning electron microscope (SEM) (Paragraph 0137), an average long pore diameter of pores present in the microporous layer (X) is 220 nm or more and 400 nm or less (Claim 28 discloses the average longest pore diameter is 100-2000 nm.).
However, Hamasaki et al. do not teach a pentad fraction of the polypropylene is 98.5% or greater.
Nemoto et al. teach a separator for a battery (Abstract). The separator can comprise a polypropylene resin having a pentad fraction of 80-99% (Paragraph 0045).
Therefore, it would have been obvious to one of ordinary skill in the art to modify the polypropylene material of the separator of Hamasaki with that of Nemoto in order to improve air permeability and mechanical strength.
Regarding claim 5, Hamasaki and Nemoto et al. teach the electricity storage device separator according to claim 1. Further, Hamasaki et al. teach wherein a ratio (SMD/STD) of tensile strength in machine direction (SMD) to tensile strength in width direction (STD) of the electricity storage device separator is SMD/STD > 5 (Table 7 discloses tensile strength results in MD and TD direction. The ratio of SMD/STD for example 1 is 13.).
Regarding claim 7, Hamasaki and Nemoto et al. teach the electricity storage device separator according to claim 1. Further, Hamasaki et al. teach wherein an air permeability of the electricity storage device separator when converted into a thickness of 14 µm (Paragraph 0129 discloses a separator thickness of 14 microns.) is 250 s/100 cm3 or less (Paragraph 0052 discloses an air permeability resistance of 100-500 seconds/100 mL.).
Regarding claim 8, Hamasaki and Nemoto et al. teach the electricity storage device separator according to claim 1. Further, Hamasaki et al. teach having a thickness of 8 µm or more and 18 µm or less and a puncture strength of 230 gf or more when the separator is converted into a thickness of 14 µm (Paragraph 0053 discloses the separator has a puncture strength of 400 gf or more, provided that the puncture strength is a value obtained by multiplying an actual measured puncture strength of the separator by 14 µm after dividing the actual measured puncture strength by a thickness of the separator.).
Regarding claims 10, Hamasaki and Nemoto et al. teach the electricity storage device separator according to claim 1. Further, Hamasaki et al. teach wherein a ratio of the polypropylene to the polyolefin (A) is 50 to 100% by mass. (Claim 1 discloses the microporous membrane comprises a polypropylene resin and a thermoplastic monomer. Claim 7 discloses the weight ratio of the polypropylene resin (A) to the thermoplastic elastomer (B) is 99.9:0.1 to 80:20.).
Regarding claims 14 and 17, Hamasaki and Nemoto et al. teach the electricity storage device separator according to claim 1. Further, Hamasaki et al. teach further comprising a microporous layer (Y) mainly composed of a polyolefin (B); wherein a main component of the polyolefin (A) is polypropylene, and a main component of the polyolefin (B) is polyethylene (Paragraph 0056 discloses a the separator comprises a microporous multi-layered membrane in which the microporous membrane comprising the polypropylene resin (A) and the thermoplastic elastomer (B) and a microporous membrane comprising a polyethylene as a major component.).
Regarding claim 18, Hamasaki and Nemoto et al. teach the electricity storage device separator according to claim 1. Further, Hamasaki et al. teach wherein a porosity of the electricity storage device separator is 20% or greater and 70% or less (Paragraph 0095 discloses a porosity of the microporous membrane is 30 to 80%.).
Claims 3 and 4 are rejected under 35 U.S.C. 103 as being unpatentable over Hamasaki et al. (WO 2019/103947 A1 using US 2021/0367309 A as an English language translation.) and Nemoto et al. (US 2013/0196208 A1) as applied to claim 1 above, and further in view of Obara et al. (JP 2012-092286 A).
Regarding claim 3 and 4, Hamasaki and Nemoto et al. teach the electricity storage device separator according to claim 1. Further, Hamasaki et al. disclose a melt tension of the microporous layer (X) is measured at a temperature of 230 °C (Paragraphs 0139-0141). However, they do not teach wherein the melt tension is 16 mN or more and 40 mN or less
Obara et al. teach a propylene-based resin micropore film for use in a lithium-ion battery (Abstract). Further, the melt tension is at 1.1-3.2 grams which would yield 11-31 mN (Abstract).
Therefore, it would have been obvious to one of ordinary skill in the art to modify Hamasaki with Obara in order to improve mechanical strength.
Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Hamasaki et al. (WO 2019/103947 A1 using US 2021/0367309 A as an English language translation.) and Nemoto et al. (US 2013/0196208 A1) as applied to claim 1 above, and further in view of Ishihara et al. (US 2013/0302696 A1), and further in view of Ohya et al. (US 2018/0233730 A1).
Regarding claim 6, Hamasaki and Nemoto et al. teach the electricity storage device separator according to claim 1. However, they do not teach wherein a heat shrinkage rate of the electricity storage device separator after 1 h of heat treatment at 105 °C is 1% or less in TD and 4% or less in MD, and a heat shrinkage rate of the electricity storage device separator after 1 h of heat treatment at 120 °C is 1% or less in TD and 10% or less in MD.
Ishihara et al. teach a microporous membrane comprising polyolefin materials (Abstract; claim 1) to be used in a separator for a battery device (Paragraph 0001). Further, the microporous membrane of the present invention preferably has a TD heat shrinkage rate at 105°C of 5% or less, more preferably 2.0%, and still more preferably 0.01 to 0.5%. The microporous membrane of the present invention preferably has a MD heat shrinkage at 105°C of 5% or less, and more preferably 0.5 to 5% (Paragraph 0103).
Therefore, it would have been obvious to one of ordinary skill in the art to modify Hamasaki with Ishihara in order to provide a microporous membrane having a high meltdown temperature, a low shutdown temperature, and resistance to heat shrinkage at high temperatures.
However, neither Hamasaki nor Ishihara et al. teach a heat shrinkage rate of the electricity storage device separator after 1 h of heat treatment at 120 °C is 1% or less in TD and 10% or less in MD.
Ohya et al. teach a porous film comprising a polyolefin such as polypropylene for use in a battery separator (Abstract; claim 1; paragraph 001). Further, the film has a heat shrinkage percentage in the machine direction is 1% or less at 110° C. and a heat shrinkage percentage in the direction substantially orthogonal to machine direction is −1.7% to −1.0% at 110° C (Claim 4). Further, while Ohya does not teach 120° C, this is merely an example of optimization within prior art conditions or through routine experimentation MPEP 2144.05 IIA: Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955).
Therefore, it would have been obvious to one of ordinary skill in the art to modify Hamasaki and Ishihara with Ohya in order to minimize warpage.
Claims 12 and 13 are rejected under 35 U.S.C. 103 as being unpatentable over Hamasaki et al. (WO 2019/103947 A1 using US 2021/0367309 A as an English language translation.) and Nemoto et al. (US 2013/0196208 A1) as applied to claim 1 above, and further in view of Mizuno et al. (US 2016/0013461 A1).
Regarding claims 12 and 13, Hamasaki and Nemoto et al. teach the electricity storage device separator according to claim 1. However, they do not teach wherein a weight average molecular weight (Mw) of the microporous layer (X) is 500,000 or greater and 1,500,000 or less; wherein a value (Mw/Mn) obtained by dividing a weight average molecular weight (Mw) by a number average molecular weight (Mn) of the microporous layer (X) is 6 or less.
Mizuno et al. teach a polyolefin porous membrane for use in a battery separator (Abstract). Further, the molecular weight of the microporous layer (X) is 500,000 or greater and 1,500,000 or less (Paragraph 0051) and wherein a value (Mw/Mn) obtained by dividing a weight average molecular weight (Mw) by a number average molecular weight (Mn) of the microporous layer (X) is 6 or less (Paragraph 0055 discloses a molecular weight distribution (Mw/Mn) of the polyethylene resin, namely, the ratio of weight average molecular weight (Mw) to number-average molecular weight (Mn), is preferably in the range from 5 to 200.).
Therefore, it would have obvious to one of ordinary skill in the art to modify Hamasaki with Mizuno in order to provide sufficient mechanical strength upon decreasing polyethylene porous membrane thickness.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DANIEL S GATEWOOD whose telephone number is (571)270-7958. The examiner can normally be reached M-F 8:00-5:30.
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Daniel S. Gatewood, Ph.D.
Primary Examiner
Art Unit 1729
/DANIEL S GATEWOOD, Ph. D/Primary Examiner, Art Unit 1729 July 17th, 2026
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