DETAILED ACTION
Response to Amendment
Applicant’s amendment filed on December 30, 2025, has been entered. Claims 1-2 and 7-16 remain pending in the application. Applicant’s amendment to the claims has overcome the rejections under 35 U.S.C. 102 and 35 U.S.C. 112, as well as the claim objections of record.
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.
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, 2, 7, 8, 9, 10, 11, 12, and 16 are rejected under 35 U.S.C. 103 as being unpatentable over JP 2018166062 A (Imamura ‘062 – citing to the English translation from the IDS filed 7/14/25) in view of CN 105940530 A (Aoki ‘530 - citing to the attached English translation), and further in view of US 20030087152 A1 (Shindo ‘152).
Regarding claim 1, Imamura ‘062 teaches a coating liquid composition (applying a coating liquid to at least one surface of a polyolefin microporous membrane substrate, and drying the coating to form at least one coating layer; [0011]; a polyolefin resin composition; [0034]), comprising: a filler (the polyolefin resin composition may contain additives including inorganics fillers; [0034]), a solvent (the solvent for the coating liquid may be water or ethanol; [0052]), a dispersant (the coating liquid may contain a dispersant; [0054]; an aqueous solution of ammonium polycarboxylate (SN Dispersant 5468); [0104]), a thickener (the coating liquid may contain a water-soluble or water-insoluble thickener; [0051] & [0054]; 4.0 parts by mass of acrylic latex and 0.6 parts by mass of carboxymethyl cellulose (CMC) was added to the dispersion liquid; [0070], [0073], & [0104]), and a binder (the coating liquid contains inorganic particles and a binder; [0050]), wherein
when the coating liquid composition is applied to a substrate to form a coating film (applying a coating liquid to at least one surface of a polyolefin microporous membrane substrate, and drying the coating to form at least one coating layer film; [0011] & [0017]) having a thickness of 0.5 to 20 µm (the thickness of the coating layer is 1 to 10 µm; [0082]).
Imamura ‘062 does not disclose that the thickener comprises a poly-N-vinylcarboxylic acid amide and a salt of carboxymethylcellulose, the poly-N-vinylcarboxylic acid amide is poly-N-vinylacetamide, a mass ratio of the poly-N-vinylacetamide to the sodium salt of carboxymethylcellulose (poly-N-vinylacetamide/sodium salt of carboxymethylcellulose) is 0.0001 or more in terms of solid content, wherein a viscosity of the thickener is 75 mPa*s or more, and 100000 mPa*s or less.
Aoki ‘530 discloses a thickening and dispersing agent used to improve adhesion between the positive electrode active materials and to the current collector, as well as to improve the dispersibility and the stability of the positive electrode active materials in a lithium-ion secondary battery positive electrode slurry ([0057]).
The thickening and dispersing agent contains one or more of the following water-soluble polymers, including carboxymethyl cellulose and poly-N-vinyl acetamide ([0025]). Cellulose derivatives (including their salts) such as carboxymethyl cellulose, impart appropriate viscosity to the slurry used in the positive electrode of a lithium-ion secondary battery ([0059]). From the viewpoint of thickening and dispersing the slurry for the positive electrode, the viscosity is preferably 1 to 10,000 mPa*s ([0061]), overlapping with 75 mPa*s to 100000 mPa*s.
In paragraph [0028] of the PG Pub (US 20230352798 A1), the mass ratio of poly-N-vinylacetamide/sodium salt of carboxymethylcellulose) in the specified range is related to both components in the coating liquid composition having good dispersibility. Aoki ‘530 discloses that the thickener and dispersing agent containing one or more of carboxymethyl cellulose and poly-N-vinyl acetamide improves dispersibility ([0057] & [0061]). Thus, the thickener including a selection of poly-N-vinylacetamide and a salt of carboxymethylcelluloseis in a specific mass ratio is considered a results effective variable that is rendered obvious by Aoki ‘530.
“[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.” See In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). The discovery of an optimum value of a known result effective variable, without producing any new or unexpected results, is within the ambit of a person of ordinary skill in the art. See In re Boesch, 205 USPQ 215 (CCPA 1980) (see MPEP § 2144.05, II.).
Therefore, it would have been obvious to select both poly-N-vinyl acetamide and carboxymethyl cellulose, as the thickening and dispersing agents, within a specific mass ratio of one to the other, having the claimed viscosity, to improve dispersibility and stability in the coating, because the selection of a known material, which is based upon its suitability for the intended use, is within the ambit of one of ordinary skill in the art. See In re Leshin, 125 USPQ 416 (CCPA 1960) (see MPEP § 2144.07), and the specific mass ratio does not produce any new or unexpected results.
Further, as set forth in MPEP 2144.05, in the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art”, a prima facie case of obviousness exists (In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990)).
Aoki ‘530 does not disclose that the salt of carboxymethylcellulose is a sodium salt of carboxymethyl cellulose.
Shindo ‘132 discloses that in order to improve the binding ability of cohesiveness of an active material layer, it is preferred to incorporate a thickener, wherein specific examples of the thickener include a sodium salt of carboxymethylcellulose (CMC).
Therefore, it would have been obvious to a person of ordinary skill in the art to select a sodium salt of CMC as the salt of CMC, as suggested by Shindo ‘132, in the coating liquid composition, as taught by Imamura ‘062, because the selection of a known material, which is based upon its suitability for the intended use, is within the ambit of one of ordinary skill in the art. See In re Leshin, 125 USPQ 416 (CCPA 1960) (see MPEP § 2144.07).
While the cited references do not explicitly disclose a shrinkage rate of 15% or less after heating at 170 °C for 15 minutes, the limitation of the shrinkage rate being 15% or less after heating at 170°C for 15 minutes is presumed to be an inherent property of the coating liquid composition.
As discussed in [0011] of the present specification, the coating film having the claimed shrinkage rate appears to be based upon the materials of the coating liquid composition and the thickness of the coating film when the coating liquid composition is applied to the substrate. The cited references teach all of the recited materials/elements of the coating liquid composition in claim 1, including the coating film thickness. Accordingly, the coating liquid composition taught by the cited references would be expected to have the same shrinkage rate property, because the structure taught by the cited references is identical to the structure recited in the claims.
Regarding product and apparatus claims, when the structure recited in the reference is substantially identical to that of the claims, claimed properties or functions are presumed to be inherent. The Courts have held that it is well settled that where there is a reason to believe that a functional characteristic would be inherent in the prior art, the burden of proof then shifts to the applicant to provide objective evidence to the contrary. See In re Schreiber, 128 F.3d at 1478, 44 USPQ2d at 1478, 44 USPQ2d at 1432 (Fed. Cir. 1997) (see MPEP § 2114 I.).
Regarding claim 2, Imamura ‘062 teaches the coating liquid composition according to claim 1, wherein a content of the filler is 20% by mass or more and 70% by mass or less (the inorganic particles, corresponding to the filler, may be alumina or aluminum hydroxide oxide; [0059]; wherein the aluminum hydroxide oxide is contained in an amount of 95 parts based on a total of 200 parts in example 1, which is about 47.5%, falling within the claimed range; [0104]).
Regarding claim 7, Imamura ‘062 teaches the coating liquid composition according to claim 1, wherein the solvent is water (the solvent for the coating liquid may be water; [0052] of Imamura ‘062).
Regarding claim 8, Imamura ‘062 teaches the coating liquid composition according to claim 1, wherein the binder is an emulsion selected from an acrylic emulsion and a styrene-butadiene polymer emulsion (examples of resin binders include styrene-butadiene copolymers, acrylonitrile-butadiene copolymers, acrylonitrile-butadiene-styrene copolymers; [0070]; from the viewpoint of improving electrochemical stability and binding properties, the resin latex binder is preferably one obtained by emulsion polymerization; [0074] of Imamura ‘062).
Regarding claim 9, Imamura ‘062 teaches the coating liquid composition according to claim 1, wherein an amount of the binder is 1 part by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the filler (4.0 parts by mass of acrylic latex and 95.0 parts of aluminum hydroxide oxide, which falls within the claimed range; [0104] of Imamura ‘062).
Regarding claim 10, Imamura ‘062 teaches a substrate with a coating film, comprising a coating film formed from the coating liquid composition according to claim 1 and a substrate (applying a coating liquid to at least one surface of a polyolefin microporous membrane substrate, and drying the coating to form at least one coating layer; [0011]; a polyolefin resin composition; [0034] of Imamura ‘062; see claim 1 above).
Regarding claim 11, Imamura ‘062 teaches the substrate with the coating film according to claim 10, wherein the substrate is a polyolefin film (applying a coating liquid to at least one surface of a polyolefin microporous membrane substrate, and drying the coating to form at least one coating layer; [0011]; a polyolefin resin composition; [0034] of Imamura ‘062).
Regarding claim 12, Imamura ‘062 teaches the substrate with the coating film according to claim 11, wherein the polyolefin film is at least one selected from a polyethylene film and a polypropylene film (when the polyolefin microporous membrane substrate is used as a battery separator, polyethylene may be used as the polyolefin resin; [0032] of Imamura ‘062).
Regarding claim 16, Imamura ‘062 teaches an electrode material comprising a coating film formed from the coating liquid composition according to claim 1 on a surface of a polypropylene substrate (applying a coating liquid to at least one surface of a polyolefin microporous membrane substrate, and drying the coating to form at least one coating layer; [0011]; a polyolefin resin composition; [0034]; as the polyolefin resin, polypropylene may be used; [0029] of Imamura ‘062; see claim 1 above; also see [0012] of the PG Pub stating that the coating film can be used as an electrode material, thus the coating layer disclosed by Imamura ‘062 is being interpreted as the electrode material that can be used in a secondary battery).
Claims 13, 14, and 15 are rejected under 35 U.S.C. 103 as being unpatentable over JP 2018166062 A (Imamura ‘062 – citing to the English translation from the IDS filed 7/14/25) in view of CN 105940530 A (Aoki ‘530 - citing to the attached English translation) and US 20030087152 A1 (Shindo ‘152), and further in view of US 20160056435 A1 (Takeda ‘435).
Regarding claim 13, Imamura ‘062 teaches the substrate with a coating film according to claim 12, wherein the polyolefin resins may be used alone or in combination of two or more, for example polyethylene and polypropylene ([0027] – [0029] of Imamura ‘062), but does not explicitly disclose that the substrate is a three-layer laminated film of polypropylene, polyethylene, and polypropylene.
Takeda ‘435 discloses a separator substrate that may be used in a nonaqueous electrolyte secondary battery ([0027]). The separator substrate may include a porous resin sheet (film) formed of a resin such as polyethylene (PE), polypropylene (PP), polyester, cellulose, or polyamide ([0027]). The porous resin sheet may have a single-layer structure, or a multilayer structure including two or more layers (for example, a three-layer structure (that is, a PP/PE/PP structure) in which a PP layer is laminated on opposite surfaces of a PE layer) ([0027]).
Therefore, it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention, to modify the structure of the substrate with the coating film, as taught by Imamura ‘062, to be a three-layer laminated film of polypropylene, polyethylene, and polypropylene, as suggested by Takeda ‘435, because the simple substitution of one known element for another is likely to be obvious when predictable results are achieved. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395 – 97 (2007) (see MPEP § 2143, B.).
Further, the selection of a known material, which is based upon its suitability for the intended use, is within the ambit of one of ordinary skill in the art. See In re Leshin, 125 USPQ 416 (CCPA 1960) (see MPEP § 2144.07).
Regarding claim 14, modified Imamura ‘062 teaches a separator comprising the substrate with the coating film according to claim 13 (after coating, a separator was obtained; [0001] & [0104] – [0107] of Imamura ‘062).
Regarding claim 15, modified Imamura ‘062 teaches a secondary battery using the separator according to claim 14 (after coating, a separator was obtained for an electricity storage device, i.e., a secondary battery; [0001], [0002], & [0105] of Imamura ‘062).
Response to Arguments
Applicant's arguments filed on December 30, 2025, have been fully considered.
Applicant asserts that Imamura ‘062 only lists CMC, and there is no mention of combining CMC with other thickeners. Thus, Imamura ‘062 does not disclose the mass ratio of the solids of the poly-N-vinyl acetamide to the sodium salt of carboxymethyl cellulose. The arguments directed to Matsumoto ‘183 are moot, because Matsuomoto ‘183 is not relied on in this Office action. Instead, Aoki ‘530 and Shindo ‘132 are relied on in this Office action to remedy the asserted deficiencies of Imamura ‘062.
Aoki ‘530 discloses that the thickening and dispersing agent contains one or more of the following water-soluble polymers, including carboxymethyl cellulose and poly-N-vinyl acetamide ([0025]). Cellulose derivatives (including their salts) such as carboxymethyl cellulose, impart appropriate viscosity to the slurry used in the positive electrode of a lithium-ion secondary battery ([0059]). From the viewpoint of thickening and dispersing the slurry for the positive electrode, the viscosity is preferably 1 to 10,000 mPa*s ([0061]).
Therefore, it would have been obvious to select both poly-N-vinyl acetamide and carboxymethyl cellulose, as the thickening and dispersing agents, within a specific mass ratio of one to the other, having the claimed viscosity, to improve dispersibility and stability in the coating, because the selection of a known material, which is based upon its suitability for the intended use, is within the ambit of one of ordinary skill in the art. See In re Leshin, 125 USPQ 416 (CCPA 1960) (see MPEP § 2144.07), without unexpected results.
Shindo ‘132 discloses that in order to improve the binding ability of cohesiveness of an active material layer, it is preferred to incorporate a thickener, wherein specific examples of the thickener include a sodium salt of carboxymethylcellulose (CMC).
Therefore, it would have been obvious to a person of ordinary skill in the art to select a sodium salt of CMC as the salt of CMC, as suggested by Shindo ‘132, in the coating liquid composition, as taught by Imamura ‘062, because the selection of a known material, which is based upon its suitability for the intended use, is within the ambit of one of ordinary skill in the art. See In re Leshin, 125 USPQ 416 (CCPA 1960) (see MPEP § 2144.07).
While the cited references do not explicitly disclose a shrinkage rate of 15% or less after heating at 170 °C for 15 minutes, the limitation of the shrinkage rate being 15% or less after heating at 170°C for 15 minutes is presumed to be an inherent property of the coating liquid composition.
As discussed in [0011] of the present specification, the coating film having the claimed shrinkage rate appears to be based upon the materials of the coating liquid composition and the thickness of the coating film when the coating liquid composition is applied to the substrate. The cited references teach all of the recited materials/elements of the coating liquid composition in claim 1, including the coating film thickness. Accordingly, the coating liquid composition taught by the cited references would be expected to have the same shrinkage rate property, because the structure taught by the cited references is identical to the structure recited in the claims.
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 TAYLOR H KRONE whose telephone number is (571)270-5064. The examiner can normally be reached Monday through Friday from 9:00 AM - 6:00 PM EST.
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/TAYLOR HARRISON KRONE/Examiner, Art Unit 1725
/NICOLE M. BUIE-HATCHER/ Supervisory Patent Examiner, Art Unit 1725