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 .
Summary
The Applicant’s arguments and claim amendments received April 15, 2026 have been entered into the file. Currently, claim 1 is amended; and claims 2 and 8 are cancelled; resulting in claims 1, 3-7, and 9-15 pending for examination.
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, 3-7, and 9-15 are rejected under 35 U.S.C. 103 as being unpatentable over Hyo, et al. (KR 20150059621 A), cited on IDS, in view of Yao, et al. (US 2021/0265702 A1).
Regarding claim 1, Hyo teaches a separation membrane used in batteries including a polyolefin-based substrate film (porous substrate) and a coating layer formed on one or both sides of the substrate film comprising an organic binder and inorganic particles (¶ [0008], Ln. 1-4). Hyo teaches that the organic binder includes an acrylic copolymer comprising a repeating unit derived from a (meth)acrylate-based monomer and a repeating unit derived from an acetate group-containing monomer (¶ [0008], Ln. 4-6). Hyo specifically teaches that the (meth)acrylate-based monomer is selected from the group consisting of butyl (meth)acrylate, propyl (meth)acrylate, ethyl (meth)acrylate, and methyl (meth)acrylate, and that the acetate group-containing monomer is selected from either vinyl acetate or allyl acetate (¶ [0018], Ln. 5-9). Thus, Hyo anticipates the combination of methyl acrylate and vinyl acetate, resulting in the claimed structure of Chemical Formula 1. As Hyo teaches a small list of possible (meth)acrylate-based monomers and only two acetate group-containing monomers, a person of ordinary skill in the art would ‘at once envisage’ the claimed arrangement or combination from the disclosure in the reference (MPEP 2131.02(III)). Hyo further teaches that the molar ratio of the (meth)acrylate-based monomer to the acetate group-containing monomer is within 3:7 to 7:3, within the claimed range of 80:20 to 20:80 (¶ [0024], Ln. 1-4). Hyo does not expressly teach that the weight average molecular weight of the copolymer is within 100,000 and 300,000.
Yao teaches a composite separator for a lithium battery including a base film and coating layer on one or both sides of the base film (¶ [0008], Ln. 1-4). Yao teaches that the coating layer is formed by a coating slurry which includes a fluorine resin polymer or acrylic resin polymer, inorganic nanoparticles, and an organic solvent (¶ [0009], Ln. 1-6). The fluorine resin polymer or acrylic resin polymer contains at least one selected from the group consisting of polyvinylidene fluoride, a polyvinylidene fluoride and hexafluoropropylene copolymer, a polyvinylidene fluoride and dichloroethylene copolymer, polystyrene, n-butyl polyacrylate, polymethyl methacrylate, polyethylmethacrylate, poly(t-butyl acrylate), polyvinyl acetate, polyacrylonitrile, polyvinyl acetate, acrylamide and polymethyl acrylate (¶ [0013], Ln. 1-9). Yao further teaches that the molecular weight of the fluorine resin polymer or acrylic resin polymer is preferably 200,000-300,000 (¶ [0013], Ln. 9-11).
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the weight average molecular weight of the copolymer of Hyo to be within the range of 200,000-300,000 based on the teachings of Yao. As Hyo teaches including methyl acrylate and vinyl acetate in a molar ratio of 3:7 to 7:3, one of ordinary skill in the art would reasonably expect to result in a copolymer having a molecular weight within the claimed range of 100,000-300,000. Further, as Yao teaches a similar coating layer on a separator for a lithium battery including a polymer and inorganic particles, with monomers for the polymer including methacrylates and polyvinyl acetate, one of ordinary skill in the art would find it obvious to apply the teachings of the preferred molecular weight of the polymer to the copolymer of Hyo. One of ordinary skill in the art would understand that heavier polymers provide better adhesion but can be more difficult to work with while lighter polymers can be easier to apply, and would be motivated to adjust the molecular weight of the polymer to produce a coating with high adhesion and that can be applied to the substrate film easily. Thus, one of ordinary skill in the art would find it obvious to modify the weight average molecular weight of the copolymer of Hyo to be within 200,000-300,000 based on the teachings of Yao that the molecular weight range is preferred for a polymer included in a separator coating.
Regarding claim 3, Hyo in view of Yao teaches all of the limitations of claim 1, including a copolymer of the humidification phase separable polymer methyl acrylate, having a glass transition temperature less than 100 °C, and vinyl acetate, having a glass transition temperature of 10 °C to 60 °C.
Regarding claim 4, Hyo in view of Yao teaches all of the limitations of claim 1 above and Hyo further teaches that the copolymer is produced by polymerizing the (meth)acrylate-based monomer and acetate group-containing monomer at a molar ratio of 3:7 to 7:3, within the claimed range of 80:20 to 20:80 (¶ [0024], Ln. 214-217).
Regarding claim 5, Hyo in view of Yao teaches all of the limitations of claim 1 above, including a copolymer of methyl acrylate and vinyl acetate having the structure of claimed Chemical Formula 1, and therefore, is a block copolymer.
Regarding claim 6, Hyo in view of Yao teaches all of the limitations of claim 1 above. The combination of reference does not expressly teach that the vinyl acetate has an adhesive force of 200 gf/25mm or more under conditions of 60 °C and 6.5 MPa, however, it would be obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to use vinyl acetate with an adhesive force of 200 gf/25mm or more under conditions of 60 °C and 6.5 MPa. One would be motivated to use vinyl acetate with a high adhesive force with respect to the separator in order to effectively adhere the separator to the electrodes.
Regarding claim 7, Hyo in view of Yao teaches all of the limitations of claim 1 above. While it is acknowledged that the humidification phase separable polymer being phase-separated at a temperature of 25 °C to 80 °C and a relative humidity of 40% to 80% is not expressly recited by the references, Hyo teaches the claimed composition, including a copolymer having the claimed structure of Formula 1 with similar glass transition temperatures. The phase separation at a temperature of 25 °C to 80 °C and a relative humidity of 40% to 80% would be implicitly achieved by a separator with the same copolymer composition and properties. The instant specification has not provided adequate teachings that the claimed property is only obtainable with the claimed material.
As evidence that the claimed property is inherent to the separator taught by Hyo, the reference teaches a separator with substantially the same composition and properties as the claimed separator. Paragraph [76] of the instant specification indicates that the acrylate-based binder is manufactured through copolymerization of a monomer having a low glass transition temperature and a monomer having a high glass transition temperature in a predetermined ratio. Specifically, examples 1-3 of the instant specification disclose a copolymer consisting of vinyl acetate and methyl acrylate in molar ratios of 80:20, 60:40, and 40:60, respectively.
With respect to the composition, Hyo teaches a copolymer of vinyl acetate and methyl acrylate in a molar ratio of 3:7 to 7:3, as described above. Thus, the humidification-phase separable polymer would achieve the claimed phase separation at a temperature of 25 °C to 80 °C and a relative humidity of 40% to 80%.
Regarding claim 9, Hyo in view of Yao teaches all of the limitations of claim 1 above and Hyo further teaches that the inorganic particles may be included in the coating layer in an amount of 70-99 wt% based on the total weight of the coating layer (¶ [0028], Ln. 263-265). Specifically, in Example 5, Hyo teaches a coating layer including a weight ratio of inorganic material to acrylic copolymer binder of 6:1 (approximately 86:14), within the claimed range of 60:40 to 90:10 (¶ [0065], Ln. 651-653).
Regarding claim 10, Hyo in view of Yao teaches a separator meeting the limitations of claim 1 as detailed above. Hyo further teaches a cell is manufactured by positioning the separator between the positive and negative electrodes of the cell, and filling the separator with electrolyte (¶ [0046], Ln. 468-471). Hyo teaches that the cell is particularly a lithium secondary battery (¶ [0010], Ln. 96-98).
Regarding claims 11-14, Hyo in view of Yao teaches all of the limitations of claim 10 above and Hyo further teaches that the coating layer may be formed on one or both sides of the base film (¶ [0013], Ln. 117-118). The combination of references does not expressly teach that the coating layer facing the positive electrode and the film facing the negative electrode have different constituents. Additionally, the combination of references does not expressly teach that the copolymer is only present in the coating layer facing the positive electrode. Hyo does not expressly teach that the composition ratio of the constituents in the film is different between the film facing the positive electrode and the film facing the negative electrode, or that the film facing the positive electrode comprises a larger amount of the copolymer than the film facing the negative electrode.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to modify the coating layer of Hyo to have different constituents and copolymer compositions for the side facing the positive electrode and the side facing the negative electrode. One of ordinary skill in the art would recognize that because the positive electrode and negative electrode have different compositions, alternate compositions of coating layer could be used to bond the separator to the negative electrode, including coating layers with a lower amount of copolymer, or no copolymer. It would be obvious to select a coating layer based on the composition of the electrode. One would be motivated to modify the coating film of Hyo to have different constituents and copolymer compositions for the side facing the positive electrode and the side facing the negative electrode in order to effectively bind the separator to the electrodes.
Regarding claim 15, Hyo in view of Yao teaches all of the limitations of claim 10 above. While it is acknowledged that a force of adhesion between the separator and the positive electrode of 50 gf/25mm or more under conditions of 60 °C and 6.5 MPa is not expressly recited by the references, Hyo teaches a separator and positive electrode with substantially the same compositions. A force of adhesion between the separator and the positive electrode of 50 gf/25mm or more under conditions of 60 °C and 6.5 MPa would be implicitly achieved by a separator and positive electrode with substantially the same compositions. The instant specification has not provided adequate teachings that the claimed property is only obtainable with the claimed material.
As evidence that the claimed property is inherent to the separator taught by Hyo in view of Yao, Hyo teaches a separator and positive electrode with substantially the same compositions as the separator and positive electrode as the instant specification. Paragraph [43] of the instant specification indicates that the substrate of the separator is a porous substrate that may include a polyolefin-based resin such as polyethylene, polypropylene, polybutene, polyisobutylene, or polymethylpentene. Paragraph [95] of the instant specification indicates that the positive electrode active material may be a lithium nickel oxide, lithium manganese oxide, lithium copper oxide, or vanadium oxide. Paragraphs [96]-[97] add that the conductive material may be graphite, carbon black, conductive fiber, metallic powder, conductive whisker, or a conductive metal oxide, and the binder may be polyvinylidene fluoride, polyvinyl alcohol, CMC, starch, hydroxypropyl cellulose, regenerated cellulose, polyvinyl pyrrolidone, tetrafluoroethylene, polyethylene, polypropylene, EPDM, sulfonated EPDM, styrene butylene rubber, or fluoro rubber.
With respect to the substrate, Hyo teaches that the separator may be a polyolefin-based substrate such as polyethylene, a polypropylene, or a polyethylene/polypropylene stacked film (¶ [0014], Ln. 122-129).
With respect to the positive electrode, Hyo teaches that the positive electrode active material may include a lithium manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium iron oxide, or a lithium composite oxide combining these (¶ [0048], Ln. 486-488). Hyo additionally teaches that the conductive agent included in the examples is carbon black and the binder is a combination of CMC and SBR (¶ [0082], Ln. 878-882).
Therefore, Hyo in view of Yao teaches a separator and positive electrode with substantially the same compositions, and thus would achieve the claimed force of adhesion between the separator and the positive electrode of 50 gf/25mm or more under conditions of 60 °C and 6.5 MPa.
Response to Arguments
Response-Claim Rejections – 35 U.S.C. 112
The previous rejections of claims 1, 3-7, and 9-15 under 35 U.S.C. 112(b) as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention are overcome by the Applicant’s amendments to claim 1 in the response filed April 15, 2026.
Response-Claim Rejections – 35 U.S.C. 103
In light of the Applicant’s amendments to claim 1, the previous rejections of claims 1, 3-7, and 9-15 under 35 U.S.C. 103 over Shon, et al. (US 2017/0149039 A1) have been withdrawn. Applicant’s arguments with respect to the rejections of claims 1, 3-7, and 9-15 over Shon 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.
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 SARAH J JACOBSON whose telephone number is (703)756-1647. The examiner can normally be reached Monday - Friday 8:00am - 5:00pm.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Mark Ruthkosky can be reached at (571) 272-1291.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/SARAH J JACOBSON/Examiner, Art Unit 1785
/MARK RUTHKOSKY/Supervisory Patent Examiner, Art Unit 1785
Prosecution Insights