DETAILED ACTION
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 06/22/2026 has been entered.
Response to Amendment
In response to the amendment received 06/22/2026, the 35 U.S.C. 103 rejections of the claims have been maintained from the previous office action.
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.
Claim(s) 1-2, 4-5, 7-17, 22, 24, and 26 is/are rejected under 35 U.S.C. 103 as being unpatentable over Published Application US20120015229A1, hereafter Ohashi, as stated above for claim 1, and further in view of Published Application US20150155538A1, hereafter Tang.
Regarding claim 1, Ohashi discloses a multilayer battery separator (abstract, [0001]) comprising:
a first outer layer ([0070] first polyolefin microporous membrane) comprising a coextruded ([0043] extruding into sheet) blend of a polypropylene ([0076]) and a first nanoparticle inorganic filler ([0070] inorganic filler with 1-89 nm particle size); and
a second outer layer laminated to the first outer layer ([0070] second polyolefin microporous membrane laminated on the first microporous layer).
Ohashi is silent on wherein the first nanoparticle inorganic filler has an average pore size of 2-15 nm.
In the analogous art of battery separators, Tang discloses wherein the first nanoparticle inorganic filler ([0044] such as silica or titania) has an average pore size of 2-15 nm ([0043] 2-50 nm, which overlaps with the claimed range of 2-15 nm. In the case where the claimed ranges overlap or lie inside ranges disclosed by the prior art a prima facie case of obviousness exists (MPEP 2144.05 (I)). Tang further discloses the mesopores of the fine particles in the separator suction the electrolyte by a capillary action, firmly holding the electrolyte solution in the mesopores ([0043]).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the present invention, to select pore diameters of 2-15nm for the nanoparticles as disclosed by Tang in order to suction the electrolyte by a capillary action, firmly holding the electrolyte solution in the mesopores. Further, one skilled in the art would have found it obvious to select a known material based on its suitability for the intended purpose (MPEP 2144.07), and because in the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists (MPEP 2144.05 (I)).
Regarding the remaining limitation, that the first outer layer is “formed by a dry process”, the examiner notes that the patentability of a product does not depend on its method of production (MPEP 2113 (I)). As such, since the structural limitations of the claimed product are met by modified Ohashi, the claim is considered to be met by the combination.
Regarding claim 2, Ohashi discloses wherein the first nanoparticle inorganic filler comprises SiO, TiO2, or any combination thereof ([0024] one or two or more of silicon oxide and titanium oxide).
Regarding claim 4, Ohashi discloses wherein a ratio of first nanoparticle inorganic filler to polypropylene comprises 1% ([0155]), which lies inside the range of 0.1-10% (MPEP 2131.03).
Regarding claim 5, Ohashi wherein the first nanoparticle inorganic filler has an average size in three dimensions of 50-300 nm ([0070] inorganic filler with 1-89 nm particle size, which overlaps with the range of 50-300 nm, see MPEP 2131.03 (II)).
Regarding claim 7, Ohashi discloses wherein the blend of polypropylene and first nanoparticle inorganic filler is coextruded ([0178] layers formed by coextrusion).
Regarding claim 8, Ohashi discloses wherein the second outer layer (second polyolefin microporous layer) comprises a blend of a polypropylene ([0076] polyolefin is polypropylene) and a second nanoparticle inorganic filler ([0101] inorganic filler in second polyolefin microporous layer).
Regarding claim 9, Ohashi discloses wherein the first nanoparticle inorganic filler comprises SiO, TiO2, or any combination thereof ([0024] one or two or more of silicon oxide and titanium oxide).
Regarding claim 10, Ohashi discloses wherein the first nanoparticle inorganic filler and the second nanoparticle inorganic filler are the same type ([0074] layers are different from each other in porosity or pore structure, but not raw materials).
Regarding claim 11, Ohashi discloses wherein the first nanoparticle inorganic filler and the second nanoparticle inorganic filler are different types ([0074] layers are different from each other in raw materials).
Regarding claim 12, Ohashi discloses one or more inner layers positioned between the first outer layer and the second outer layer ([0090] first polyolefin microporous layers are surface layers and second polyolefin microporous layer is the intermediate layer), wherein at least one of the inner layers comprises a polypropylene ([0076] polyolefin is polypropylene).
Regarding claim 13, Ohashi discloses wherein the one or more inner layers are free of a nanoparticle inorganic filler ([0098] polyolefin resin concentration of intermediate layer may be 100% by mass).
Regarding claim 14, Ohashi discloses wherein the one or more inner layers are blended with a nanoparticle inorganic filler, with the nanoparticle inorganic filler being present in an amount less than 10 wt.% based on a total weight of the inner layer ([0098] polyolefin resin concentration of intermediate layer may be 90% by mass or more).
Regarding claim 15, Ohashi discloses wherein the one or more inner layers comprise one or more polypropylene inner layers positioned between the first outer layer and the second outer layer ([0090] first polyolefin microporous layers are surface layers and second polyolefin microporous layer is the intermediate layer; [0076] polyolefin is polypropylene).
Regarding claim 16, Ohashi discloses wherein the one or more polypropylene inner layers is free of a nanoparticle inorganic filler ([0098] polyolefin resin concentration of intermediate layer may be 100% by mass); or wherein the one or more polypropylene inner layers is blended with a nanoparticle inorganic filler ([0070] inorganic filler in at least one of the layers, implying first and second layers; [0090] first polyolefin microporous layers are surface layers and second polyolefin microporous layer is the intermediate layer).
Regarding claim 17, Ohashi discloses wherein the separator has a porosity in the range of 35% to 65% ([0345] Table 1, porosities ranging from 53-61%)
Regarding claims 22 and 24, Ohashi discloses a lithium ion battery ([0452] lithium ion batteries) comprising the membrane of claims 1 and 2 (see rejections above).
Regarding claim 26, Ohashi discloses a multilayer battery separator (abstract, [0001]) comprising:
a first outer layer ([0070] first polyolefin microporous membrane) consisting essentially of a coextruded ([0043] extruding into sheet) blend of a polypropylene ([0076]) and a first nanoparticle inorganic filler ([0070] inorganic filler with 1-89 nm particle size); and
a second outer layer laminated to the first outer layer ([0070] second polyolefin microporous membrane laminated on the first microporous layer).
Ohashi is silent on wherein the first nanoparticle inorganic filler has an average pore size of 2-15 nm.
In the analogous art of battery separators, Tang discloses wherein the first nanoparticle inorganic filler ([0044] such as silica or titania) has an average pore size of 2-15 nm ([0043] 2-50 nm, which overlaps with the claimed range of 2-15 nm. In the case where the claimed ranges overlap or lie inside ranges disclosed by the prior art a prima facie case of obviousness exists (MPEP 2144.05 (I)). Tang further discloses the mesopores of the fine particles in the separator suction the electrolyte by a capillary action, firmly holding the electrolyte solution in the mesopores ([0043]).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the present invention, to select pore diameters of 2-15nm for the nanoparticles as disclosed by Tang in order to suction the electrolyte by a capillary action, firmly holding the electrolyte solution in the mesopores. Further, one skilled in the art would have found it obvious to select a known material based on its suitability for the intended purpose (MPEP 2144.07), and because in the case where the claimed ranges "overlap or lie inside ranges disclosed by the prior art" a prima facie case of obviousness exists (MPEP 2144.05 (I)).
The examiner notes that since the limitations of “one or more additives selected from the group consisting of: an ionomer, a cellulose nanofiber, a lubricating agent, a nucleating agent, a cavitation promoter, a fluoropolymer, a cross-linker, a lithium halide, a polymer processing agent, a high temperature melt index (HTMI) polymer, an electrolyte additive, and combinations thereof” are preceded by “optionally,” the claimed optional additive is considered not to be required by the claim.
Regarding the remaining limitation, that the first outer layer is “formed by a dry process”, the examiner notes that the patentability of a product does not depend on its method of production. As such, since the structural limitations of the claimed product are met by modified Ohashi, the claim is considered to be met by the combination.
Response to Arguments
Applicant's arguments filed 06 have been fully considered but they are not persuasive.
In response to applicant’s argument regarding claim 1 on pages 6-7 of applicant’s remarks that a skilled artisan in the separator arts would readily understand that “dry process” is not merely a process limitation but rather implies structure of the resulting membrane, the examiner disagrees. First, the examiner notes that [0051] of the present specification recites that the extrusion process can proceed with or without a solvent. This fact combined with the absence of any evidence in the present specification to suggest the claimed product would be different whether the process to produce it was a wet process or a dry process suggests that no significant structural difference would result from the use of one or the other. Furthermore, as stated in the rejection, the examiner notes that the patentability of a product does not depend on its method of production (MPEP 2113 (I)). As such, since the structural limitations of the claimed product are met by modified Ohashi, the claim is considered to be met by the combination.
In response to applicant’s argument regarding claim 1 on pages 7-8 of applicant’s remarks that Tang confirms that the manner of particle incorporation affects the resulting structure, since Tang states that “in the case where an electrical insulation layer is formed of only nanoparticles without using microparticles, nanoparticles having a small particle diameter are densely laminated (packed) inside the electrical insulation layer” and that “the distance required to pass through the electrical insulation layer becomes large and the amount of voids for the ion diffusion becomes small, thereby lowering the ion conductivity”, the examiner disagrees, and notes these passages from Tang appear to demonstrate only that the size of the particles affects the resulting structure and properties, and appear to say nothing regarding the process of producing the product.
In response to applicant’s argument regarding claim 1 on page 8 of applicant’s remarks that Tang fails to teach or disclose the present claims because Tang’s electrical insulation layer is formed from microparticles that are adhered together with a binder to form a separate electrical insulation layer and the particles are not blended with polypropylene and coextruded to form an outer layer of a multilayer battery separator by a dry process, the examiner notes that one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). In this case, Tang was relied upon for the pore size of the inorganic filler being between 2-15 nm ([0043]), while Ohashi was relied upon for the rest of the limitations of claim 1, as stated in the rejection.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to TIMOTHY HEMINGWAY whose telephone number is (571)272-0235. The examiner can normally be reached M-Th 6-4.
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/T.G.H./Examiner, Art Unit 1754
/SUSAN D LEONG/Supervisory Patent Examiner, Art Unit 1754
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