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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 April 27, 2026 has been entered.
Summary
The Applicant’s arguments and claim amendments received April 27, 2026 have been entered into the file. Currently, claims 1, 6, 11-12, and 17-19 are amended; and claims 2, 4-5, and 10 are cancelled; resulting in claims 1, 3, 6-9, and 11-19 pending for examination.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(d):
(d) REFERENCE IN DEPENDENT FORMS.—Subject to subsection (e), a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
The following is a quotation of pre-AIA 35 U.S.C. 112, fourth paragraph:
Subject to the following paragraph [i.e., the fifth paragraph of pre-AIA 35 U.S.C. 112], a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
Claim 6 is rejected under 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, 4th paragraph, as being of improper dependent form for failing to further limit the subject matter of the claim upon which it depends, or for failing to include all the limitations of the claim upon which it depends.
Regarding claim 6, in the claim set filed April 27, 2026, claim 5 is cancelled and claim 6 is written as being dependent on claim 5. Therefore, claim 6 is of improper dependent form for being dependent upon a cancelled claim. For the purposes of examination, claim 6 will be treated as being dependent upon claim 1.
Applicant may cancel the claim(s), amend the claim(s) to place the claim(s) in proper dependent form, rewrite the claim(s) in independent form, or present a sufficient showing that the dependent claim(s) complies with the statutory requirements.
Claim Rejections - 35 USC § 102
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 the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1, 3, 7-9, and 12-14 are rejected under 35 U.S.C. 102(a)(1) and 102(a)(2) as being anticipated by Sasaki, et al. (US 10,193,119 B2).
Regarding claim 1, Sasaki teaches a non-aqueous secondary battery functional layer that may be coated on a separator (Col. 4, Ln. 21-28), further teaching that the functional layer functions as a porous membrane and an adhesive (porous coating layer) (Col. 2, Ln. 15-21). Sasaki teaches that the separator substrate is a porous membrane made of polyolefinic resin (Col. 23, Ln. 5-9). The functional layer includes non-conductive inorganic particles, organic particles, and optionally a particulate polymer (Col. 4, Ln. 33-36). Sasaki teaches that the organic particles have a core-shell structure wherein the core is made of a polymer having a degree of swelling in electrolysis solution of 5-30 times and the shell is made of polymer having a degree of swelling in electrolysis solution of 1-4 times (Col. 2, Ln. 44-51). Additionally, the shell polymer has a glass transition temperature of preferably 90 °C or higher (Col. 15, Ln. 30-32), indicating a melting point of higher than 90 °C. The particulate polymer prevents components contained in the functional layer from coming off and exerts higher adhesion than the organic particles when the organic particles are not swollen with electrolyte (binder polymer disposed on a surface of the core-shell polymer particles such that the core-shell polymer particles are interconnected and fixed) (Col. 17, Ln. 14-23). Specifically, in Example 6, Sasaki teaches a functional layer including barium titanate non-conductive inorganic particles, an acrylonitrile/butyl acrylate particulate polymer, and core-shell structure organic particles. The core-shell structure organic particles include a core polymer having a degree of swelling of 9.6, within the claimed range of 2-50, and a shell polymer having a degree of swelling of 1.3, within the claimed range of 2 or less, and a glass transition temperature of 105 °C, meeting the limitation of having a melting temperature of 80 °C or higher (Table 2). The shell polymer includes styrene and methacrylic acid, both of which contain an olefin (olefin-based polymer) (Table 2).
Regarding claim 3, Sasaki teaches all of the limitations of claim 1 above and further teaches that the core polymer preferably contains a cross-linkable monomer (Col. 12, Ln. 34-35). In Example 6, the core polymer contains methyl methacrylate, methacrylic acid, and ethylene glycol dimethacrylate (crosslinked polymer selected from the group including acrylic polymer) (Table 2).
Regarding claim 7, Sasaki teaches all of the limitations of claim 1 above and further teaches that the core-shell particles of Example 6 have a weight ratio of the core portion to the shell portion of 80:20, within the claimed range of 84:16 to 40:60. Specifically, Sasaki teaches that the core polymer contains 75 parts methyl methacrylate, 4 parts methacrylic acid, and 1 part ethylene glycol dimethacrylate, and the shell portion contains 19 parts styrene and 1 part methacrylic acid (Table 2).
Regarding claim 8, Sasaki teaches all of the limitations of claim 1 above and further teaches that the shell has an average thickness in percentage relative to the volume-average particle diameter D50 of the core-shell particles is preferably 5-20% (Col. 15, Ln. 49-57). Specifically, the core-shell ratio of the core-shell particles of Example 6 is 10% (Table 2), resulting in an average diameter of the core portion of 90% of the average diameter of the core-shell polymer particles, within the claimed range of 10-90%.
Regarding claim 9, Sasaki teaches all of the limitations of claim 1 above and further teaches that the separator substrate used in Example 6 is polyethylene porous material (polyolefin-containing porous polymer substrate) (Col. 28, Ln. 46).
Regarding claim 12, Sasaki teaches all of the limitations of claim 1 above including that the inorganic particles used in Example 6 are barium titanate (Table 2), having a dielectric constant of more than 5.
Regarding claims 13-14, Sasaki teaches a separator meeting the limitations of claim 1 above and further teaches that the separator is used in a lithium ion secondary battery including a positive electrode, negative electrode, and the separator interposed between the positive electrode and negative electrode (Col. 30, Ln. 5-14).
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.
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Sasaki, et al. (US 10,193,119 B2), as applied to claim 1 above.
Regarding claim 11, Sasaki teaches all of the limitations of claim 1 above. Sasaki further teaches that particulate polymer (binder polymer) preferably includes an acrylic polymer (Col. 17, Ln. 28-35). Specifically, Sasaki teaches that the acrylic polymer preferably contains a (meth)acrylonitrile monomer unit, teaching that it increases the strength of the functional layer (Col. 17, Ln. 51-54). Sasaki does not expressly teach that the particulate polymer is one of the polymers included in claim 11.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to include polyacrylonitrile in the particulate polymer based on the teachings of Sasaki. As Sasaki teaches that (meth)acrylonitrile monomer units are preferred in the particulate polymer, one of ordinary skill in the art would find it obvious to polymerize acrylonitrile monomers, forming a polyacrylonitrile particulate polymer. One of ordinary skill in the art would be motivated to polymerize acrylonitrile monomers, forming a polyacrylonitrile particulate polymer in order to strengthen the functional layer.
Claims 6 and 15-16 are rejected under 35 U.S.C. 103 as being unpatentable over Sasaki, et al. (US 10,193,119 B2) as applied to claim 1 above, and further in view of Fan (US 2021/0234233 A1).
Regarding claim 6, Sasaki teaches all of the limitations of claim 1 above. Sasaki further teaches that the core-shell polymer properties exert superior adhesion in electrolysis solution (Col. 7, Ln. 3-4). Sasaki does not expressly teach that the shell polymer is a non-crosslinked or crosslinked polymer comprising at least one of the monomers included in claim 6.
Fan teaches a separator including a porous substrate and a first coating disposed on at least a surface of the porous substrate, wherein the first coating includes a first polymer binder and first inorganic particles, further teaching that the first polymer binder includes core-shell structured particles (¶ [0005], Ln. 1-6). The porous substrate includes a polymer film, multilayer polymer film, or a non-woven fabric formed of polymers (porous polymer substrate) (¶ [0023], Ln. 1-3). Fan teaches that the core of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of ethyl acrylate, butyl acrylate, ethyl methacrylate, styrene, chlorostyrene, fluorobenzene ethylene, methylstyrene, acrylic acid, methacrylic acid, maleic acid, and any combination thereof, and that the shell of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene, chlorostyrene, fluorostyrene, methylstyrene, acrylonitrile, methyl acrylonitrile, and any combination thereof (¶ [0024], Ln. 1-15). Fan teaches that by adopting the core-shell particle structure, the uniformity of the particles is improved and, in the post-heating process, the shell of the first polymer binder may be softened first, and then the core of the first polymer binder may have bonding function (¶ [0024], Ln. 15-21).
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 shell polymer of Sasaki to include a polymer taught by Fan, such as methyl methacrylate. In polymerizing methyl methacrylate, a polymethyl methacrylate shell polymer would be formed. One of ordinary skill in the art would be motivated to modify the shell polymer based on the teachings of Fan such that the shell polymer may be softened first, increasing adhesion with the substrate.
Regarding claim 15, Sasaki teaches all of the limitations of claim 1 above. Sasaki further teaches that the core-shell polymer properties exert superior adhesion in electrolysis solution (Col. 7, Ln. 3-4). Sasaki does not expressly teach that the shell polymer comprises polymethyl methacrylate-co-n-butyl acrylate.
Fan teaches a separator including a porous substrate and a first coating disposed on at least a surface of the porous substrate, wherein the first coating includes a first polymer binder and first inorganic particles, further teaching that the first polymer binder includes core-shell structured particles (¶ [0005], Ln. 1-6). The porous substrate includes a polymer film, multilayer polymer film, or a non-woven fabric formed of polymers (porous polymer substrate) (¶ [0023], Ln. 1-3). Fan teaches that the core of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of ethyl acrylate, butyl acrylate, ethyl methacrylate, styrene, chlorostyrene, fluorobenzene ethylene, methylstyrene, acrylic acid, methacrylic acid, maleic acid, and any combination thereof, and that the shell of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene, chlorostyrene, fluorostyrene, methylstyrene, acrylonitrile, methyl acrylonitrile, and any combination thereof (¶ [0024], Ln. 1-15). In the first polymer binder of Example 1, Fan teaches that the shell includes a copolymer of methyl methacrylate and methyl styrene (¶ [0079], Ln. 1-3). Fan teaches that by adopting the core-shell particle structure, the uniformity of the particles is improved and, in the post-heating process, the shell of the first polymer binder may be softened first, and then the core of the first polymer binder may have bonding function (¶ [0024], Ln. 15-21).
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 shell polymer of Sasaki to include a polymer taught by Fan. As Fan teaches methyl methacrylate in the list of possible monomers and in the example, one of ordinary skill in the art would find it obvious to include methyl methacrylate in the shell polymer. Additionally, as Fan teaches butyl acrylate as a monomer that can be used to form the shell of the first polymer binder, one of ordinary skill in the art would find it obvious to include butyl acrylate in the shell polymer. In polymerizing methyl methacrylate and butyl acrylate, the resulting shell polymer would comprise polymethyl methacrylate-co-n-butyl acrylate. One of ordinary skill in the art would be motivated to modify the shell polymer based on the teachings of Fan such that the shell polymer may be softened first, increasing adhesion with the substrate.
Regarding claim 16, Sasaki in view of Fan teaches all of the limitations of claim 15 above. Sasaki further teaches that the core polymer preferably contains a cross-linkable monomer (Col. 12, Ln. 34-35). Sasaki teaches that the core polymer may contain an acid group-containing monomer including carboxylic acid group-containing monomers such as acrylic acid and methacrylic acid (Col. 11, Ln. 59-67). Sasaki further teaches that of the acid group-containing monomers, carboxylic acid group-containing monomers are preferred (Col. 12, Ln. 17-20). Sasaki does not expressly teach that the core polymer includes a polyacrylic acid crosslinked polymer.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to include polyacrylic acid crosslinked polymer in the core polymer based on the teachings of Sasaki. As Sasaki teaches that acrylic acid monomer units may be included in the core polymer and that it is preferred to have crosslinked polymer in the core polymer, one of ordinary skill in the art would find it obvious to polymerize acrylic acid monomers, forming a polyacrylic acid crosslinked polymer. One of ordinary skill in the art would be motivated to include polymerize acrylic acid monomers, forming a polyacrylic acid crosslinked polymer as the reference teaches that carboxylic acid group-containing monomers and cross-linkable monomers are preferred in the core polymer.
Claims 17-19 are rejected under 35 U.S.C. 103 as being unpatentable over Sasaki, et al. (US 10,193,119 B2) in view of Fan (US 2021/0234233 A1).
Regarding claim 17, Sasaki teaches a non-aqueous secondary battery functional layer that may be coated on a separator (Col. 4, Ln. 21-28), further teaching that the functional layer functions as a porous membrane and an adhesive (porous coating layer) (Col. 2, Ln. 15-21). Sasaki teaches that the separator substrate is a porous membrane made of polyolefinic resin (Col. 23, Ln. 5-9). The functional layer includes non-conductive inorganic particles, organic particles, and optionally a particulate polymer (Col. 4, Ln. 33-36). Sasaki teaches that the organic particles have a core-shell structure wherein the core is made of a polymer having a degree of swelling in electrolysis solution of 5-30 times and the shell is made of polymer having a degree of swelling in electrolysis solution of 1-4 times (Col. 2, Ln. 44-51). Additionally, the shell polymer has a glass transition temperature of preferably 90 °C or higher (Col. 15, Ln. 30-32), indicating a melting point of higher than 90 °C. The particulate polymer prevents components contained in the functional layer from coming off and exerts higher adhesion than the organic particles when the organic particles are not swollen with electrolyte (binder polymer disposed on a surface of the core-shell polymer particles such that the core-shell polymer particles are interconnected and fixed) (Col. 17, Ln. 14-23). Specifically, in Example 6, Sasaki teaches a functional layer including barium titanate non-conductive inorganic particles, an acrylonitrile/butyl acrylate particulate polymer, and core-shell structure organic particles. The core-shell structure organic particles include a core polymer having a degree of swelling of 9.6, within the claimed range of 2-50, and a shell polymer having a degree of swelling of 1.3, within the claimed range of 2 or less, and a glass transition temperature of 105 °C, meeting the limitation of having a melting temperature of 80 °C or higher (Table 2). Sasaki further teaches that the core-shell polymer properties exert superior adhesion in electrolysis solution (Col. 7, Ln. 3-4). Sasaki does not expressly teach that the shell polymer is a non-crosslinked or crosslinked polymer comprising at least one of the monomers included in claim 17.
Fan teaches a separator including a porous substrate and a first coating disposed on at least a surface of the porous substrate, wherein the first coating includes a first polymer binder and first inorganic particles, further teaching that the first polymer binder includes core-shell structured particles (¶ [0005], Ln. 1-6). The porous substrate includes a polymer film, multilayer polymer film, or a non-woven fabric formed of polymers (porous polymer substrate) (¶ [0023], Ln. 1-3). Fan teaches that the core of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of ethyl acrylate, butyl acrylate, ethyl methacrylate, styrene, chlorostyrene, fluorobenzene ethylene, methylstyrene, acrylic acid, methacrylic acid, maleic acid, and any combination thereof, and that the shell of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene, chlorostyrene, fluorostyrene, methylstyrene, acrylonitrile, methyl acrylonitrile, and any combination thereof (¶ [0024], Ln. 1-15). Fan teaches that by adopting the core-shell particle structure, the uniformity of the particles is improved and, in the post-heating process, the shell of the first polymer binder may be softened first, and then the core of the first polymer binder may have bonding function (¶ [0024], Ln. 15-21).
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 shell polymer of Sasaki to include a polymer taught by Fan, such as methyl methacrylate. In polymerizing methyl methacrylate, a polymethyl methacrylate shell polymer would be formed. One of ordinary skill in the art would be motivated to modify the shell polymer based on the teachings of Fan such that the shell polymer may be softened first, increasing adhesion with the substrate.
Regarding claim 18, Sasaki teaches a non-aqueous secondary battery functional layer that may be coated on a separator (Col. 4, Ln. 21-28), further teaching that the functional layer functions as a porous membrane and an adhesive (porous coating layer) (Col. 2, Ln. 15-21). Sasaki teaches that the separator substrate is a porous membrane made of polyolefinic resin (Col. 23, Ln. 5-9). The functional layer includes non-conductive inorganic particles, organic particles, and optionally a particulate polymer (Col. 4, Ln. 33-36). Sasaki teaches that the organic particles have a core-shell structure wherein the core is made of a polymer having a degree of swelling in electrolysis solution of 5-30 times and the shell is made of polymer having a degree of swelling in electrolysis solution of 1-4 times (Col. 2, Ln. 44-51). Additionally, the shell polymer has a glass transition temperature of preferably 90 °C or higher (Col. 15, Ln. 30-32), indicating a melting point of higher than 90 °C. The particulate polymer prevents components contained in the functional layer from coming off and exerts higher adhesion than the organic particles when the organic particles are not swollen with electrolyte (binder polymer disposed on a surface of the core-shell polymer particles such that the core-shell polymer particles are interconnected and fixed) (Col. 17, Ln. 14-23). Sasaki further teaches that the core-shell polymer properties exert superior adhesion in electrolysis solution (Col. 7, Ln. 3-4). Sasaki does not expressly teach that the shell polymer comprises polymethyl methacrylate-co-n-butyl acrylate.
Fan teaches a separator including a porous substrate and a first coating disposed on at least a surface of the porous substrate, wherein the first coating includes a first polymer binder and first inorganic particles, further teaching that the first polymer binder includes core-shell structured particles (¶ [0005], Ln. 1-6). The porous substrate includes a polymer film, multilayer polymer film, or a non-woven fabric formed of polymers (porous polymer substrate) (¶ [0023], Ln. 1-3). Fan teaches that the core of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of ethyl acrylate, butyl acrylate, ethyl methacrylate, styrene, chlorostyrene, fluorobenzene ethylene, methylstyrene, acrylic acid, methacrylic acid, maleic acid, and any combination thereof, and that the shell of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene, chlorostyrene, fluorostyrene, methylstyrene, acrylonitrile, methyl acrylonitrile, and any combination thereof (¶ [0024], Ln. 1-15). In the first polymer binder of Example 1, Fan teaches that the shell includes a copolymer of methyl methacrylate and methyl styrene (¶ [0079], Ln. 1-3). Fan teaches that by adopting the core-shell particle structure, the uniformity of the particles is improved and, in the post-heating process, the shell of the first polymer binder may be softened first, and then the core of the first polymer binder may have bonding function (¶ [0024], Ln. 15-21).
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 shell polymer of Sasaki to include a polymer taught by Fan. As Fan teaches methyl methacrylate in the list of possible monomers and in the example, one of ordinary skill in the art would find it obvious to include methyl methacrylate in the shell polymer. Additionally, as Fan teaches butyl acrylate as a monomer that can be used to form the shell of the first polymer binder, one of ordinary skill in the art would find it obvious to include butyl acrylate in the shell polymer. In polymerizing methyl methacrylate and butyl acrylate, the resulting shell polymer would comprise polymethyl methacrylate-co-n-butyl acrylate. One of ordinary skill in the art would be motivated to modify the shell polymer based on the teachings of Fan such that the shell polymer may be softened first, increasing adhesion with the substrate.
Regarding claim 19, Sasaki teaches a non-aqueous secondary battery functional layer that may be coated on a separator (Col. 4, Ln. 21-28), further teaching that the functional layer functions as a porous membrane and an adhesive (porous coating layer) (Col. 2, Ln. 15-21). Sasaki teaches that the separator substrate is a porous membrane made of polyolefinic resin (Col. 23, Ln. 5-9). The functional layer includes non-conductive inorganic particles, organic particles, and optionally a particulate polymer (Col. 4, Ln. 33-36). Sasaki teaches that the organic particles have a core-shell structure wherein the core is made of a polymer having a degree of swelling in electrolysis solution of 5-30 times and the shell is made of polymer having a degree of swelling in electrolysis solution of 1-4 times (Col. 2, Ln. 44-51). Additionally, the shell polymer has a glass transition temperature of preferably 90 °C or higher (Col. 15, Ln. 30-32), indicating a melting point of higher than 90 °C. The particulate polymer prevents components contained in the functional layer from coming off and exerts higher adhesion than the organic particles when the organic particles are not swollen with electrolyte (binder polymer disposed on a surface of the core-shell polymer particles such that the core-shell polymer particles are interconnected and fixed) (Col. 17, Ln. 14-23).
Sasaki further teaches that the core polymer preferably contains a cross-linkable monomer (Col. 12, Ln. 34-35). Sasaki teaches that the core polymer may contain an acid group-containing monomer including carboxylic acid group-containing monomers such as acrylic acid and methacrylic acid (Col. 11, Ln. 59-67). Sasaki further teaches that of the acid group-containing monomers, carboxylic acid group-containing monomers are preferred (Col. 12, Ln. 17-20). Sasaki does not expressly teach that the core polymer includes a polyacrylic acid crosslinked polymer.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to include polyacrylic acid crosslinked polymer in the core polymer based on the teachings of Sasaki. As Sasaki teaches that acrylic acid monomer units may be included in the core polymer and that it is preferred to have crosslinked polymer in the core polymer, one of ordinary skill in the art would find it obvious to polymerize acrylic acid monomers, forming a polyacrylic acid crosslinked polymer. One of ordinary skill in the art would be motivated to include polymerize acrylic acid monomers, forming a polyacrylic acid crosslinked polymer as the reference teaches that carboxylic acid group-containing monomers and cross-linkable monomers are preferred in the core polymer.
Sasaki further teaches that the core-shell polymer properties exert superior adhesion in electrolysis solution (Col. 7, Ln. 3-4). Sasaki does not expressly teach that the shell polymer comprises polymethyl methacrylate-co-n-butyl acrylate.
Fan teaches a separator including a porous substrate and a first coating disposed on at least a surface of the porous substrate, wherein the first coating includes a first polymer binder and first inorganic particles, further teaching that the first polymer binder includes core-shell structured particles (¶ [0005], Ln. 1-6). The porous substrate includes a polymer film, multilayer polymer film, or a non-woven fabric formed of polymers (porous polymer substrate) (¶ [0023], Ln. 1-3). Fan teaches that the core of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of ethyl acrylate, butyl acrylate, ethyl methacrylate, styrene, chlorostyrene, fluorobenzene ethylene, methylstyrene, acrylic acid, methacrylic acid, maleic acid, and any combination thereof, and that the shell of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene, chlorostyrene, fluorostyrene, methylstyrene, acrylonitrile, methyl acrylonitrile, and any combination thereof (¶ [0024], Ln. 1-15). In the first polymer binder of Example 1, Fan teaches that the shell includes a copolymer of methyl methacrylate and methyl styrene (¶ [0079], Ln. 1-3). Fan teaches that by adopting the core-shell particle structure, the uniformity of the particles is improved and, in the post-heating process, the shell of the first polymer binder may be softened first, and then the core of the first polymer binder may have bonding function (¶ [0024], Ln. 15-21).
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 shell polymer of Sasaki to include a polymer taught by Fan. As Fan teaches methyl methacrylate in the list of possible monomers and in the example, one of ordinary skill in the art would find it obvious to include methyl methacrylate in the shell polymer. Additionally, as Fan teaches butyl acrylate as a monomer that can be used to form the shell of the first polymer binder, one of ordinary skill in the art would find it obvious to include butyl acrylate in the shell polymer. In polymerizing methyl methacrylate and butyl acrylate, the resulting shell polymer would comprise polymethyl methacrylate-co-n-butyl acrylate. One of ordinary skill in the art would be motivated to modify the shell polymer based on the teachings of Fan such that the shell polymer may be softened first, increasing adhesion with the substrate.
Claims 1, 3, 7-9, and 12-14 are rejected under 35 U.S.C. 103 as being unpatentable over Suminosuke, et al. (JP 2015/088253 A).
Regarding claims 1, 9, and 12, Suminosuke teaches a separator for a lithium ion secondary battery, comprising a separator substrate and an adhesive layer (coating layer), wherein the adhesive layer contains a particulate polymer, and the particulate polymer has a core-shell structure (¶ [0010], Ln. 14-16). Examples of separator substrates include porous substrates made of resins containing polyolefins such as polyethylene, polypropylene, polybutene, and polyvinyl chloride, mixtures thereof, and copolymers thereof (porous polymer substrate having a plurality of pores) (¶ [0135], Ln. 1-3). Suminosuke teaches that pores are provided in the adhesive layer to increase ion diffusibility (porous coating layer) (¶ [0102], Ln. 2-3). The adhesive layer preferably further contains a binder in addition to the particulate polymer (¶ [0087], Ln. 1-2). Suminosuke teaches that by using the binder, the particulate polymer can be bonded to each other both in a state where it is swollen in the electrolytic solution and in a state where it is not swollen (binder polymer disposed partially or totally on a surface of the core-shell polymer particles and core-shell polymer particles are interconnected and fixed) (¶ [0087], Ln. 3-5).
Suminosuke teaches that the core portion of the particulate polymer is made of a polymer having a swelling degree in an electrolytic solution of 5 to 30 times (first polymer absorbs an electrolyte in an amount corresponding to 2-50 times a weight of the first polymer) and the shell portion is made of a polymer (second polymer) having a swelling degree in an electrolytic solution of more than 1 to 4 and preferably 1.2 to 3 times (¶ [0055], Ln. 4-6), overlapping the claimed range of 2 times or less. 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)). Additionally, Suminosuke teaches that the glass transition temperature of the shell polymer is preferably 70 °C or higher (¶ [0067], Ln. 1-3). The melting point temperature is higher than the glass transition temperature. A general rule of thumb is that the glass transition temperature of a polymer is 2/3 the melting point temperature, resulting in a general melting point temperature of 104 °C for the shell polymer of Suminosuke (melting point of 80 °C or higher). Suminosuke teaches that the polymer of the shell portion preferably includes an aromatic vinyl monomer (¶ [0060], Ln. 1) and additionally preferably contains amide monomer units (amide-based polymer) (¶ [0064], Ln. 1-9), further teachings that the polymer may contain crosslinkable monomer units (¶ [0062], Ln. 1). For example, the shell polymer of example 1 includes styrene and acrylamide (¶ [0224], Ln. 1).
Suminosuke teaches that the adhesive may contain non-conductive particles, which increase the mechanical strength of the adhesive layer (¶ [0114], Ln. 1-8). In referencing the non-conductive particles, Suminosuke points to the disclosure regarding non-conductive particles included in the porous membrane. The non-conductive particles may be inorganic or organic, with inorganic particles being preferred (¶ [0140], Ln. 1-6). As examples of inorganic particles, Suminosuke teaches oxide particles including titanium oxide, aluminum oxide, aluminum oxide hydrate, magnesium oxide, and magnesium hydroxide (¶ [0140], Ln. 14-16). Suminosuke does not expressly teach an embodiment in which inorganic particles are included in the adhesive layer.
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 adhesive layer of Suminosuke to include inorganic particles such as titanium oxide, which has a dielectric constant of more than 5. One of ordinary skill in the art would find it obvious to include titanium oxide in the adhesive layer as Suminosuke teaches the inclusion of non-conductive particles in the adhesive layer, and further teaches preferred examples of non-conductive particles including inorganic oxide particles, and specifically titanium oxide. One of ordinary skill in the art would be motivated to include inorganic oxide particles in the adhesive layer in order to increase the mechanical strength.
Regarding claim 3, Suminosuke teaches all of the limitations of claim 1 above and further teaches that the core polymer preferably contains a crosslinkable monomer unit (¶ [0047], Ln. 1). Specifically, in example 1, the core polymer includes 74.5 parts methyl methacrylate, 4 parts methacrylic acid, 1 part ethylene dimethacrylate, and 0.5 parts acrylamide (crosslinked polymer selected from the group including acrylic polymer) (¶ [0223], Ln. 1-3).
Regarding claim 7, Suminosuke teaches all of the limitations of claim 1 above. In looking to the examples for teachings of the weight ratio of core portion to shell portion, the core polymer of example 1 includes 74.5 parts methyl methacrylate, 4 parts methacrylic acid, 1 part ethylene dimethacrylate, and 0.5 parts acrylamide (¶ [0223], Ln. 1-3) and the shell polymer includes 19.5 parts styrene and 0.5 parts acrylamide (¶ [0224], Ln. 1), resulting in a weight ratio of the core portion to the shell portion of 80:20, within the claimed range of 84:16 to 40:60.
Regarding claim 8, Suminosuke teaches all of the limitations of claim 1 above and further teaches that diameter of the core portion is particularly preferably 70% or more and 98% or less, relative to 100% of the volume average particle diameter of the particulate polymer (¶ [0053], Ln. 1-4), overlapping the claimed range of 10% to 90%. 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 claims 13-14, Suminosuke teaches a lithium-ion secondary battery including a positive electrode, a negative electrode, an electrolyte, and the separator described above (meeting the limitations of claim 1) (¶ [0163], Ln. 1-4). The lithium-ion secondary battery is manufactured by stacking a positive electrode, a separator, and a negative electrode in this order (separator interposed between the cathode and anode) (¶ [0165], Ln. 1-3).
Claims 6, 11, and 15-16 are rejected under 35 U.S.C. 103 as being unpatentable over Suminosuke, et al. (JP 2015/088253 A) as applied to claim 1 above, and further in view of Fan (US 2021/0234233 A1).
Regarding claim 6, Suminosuke teaches all of the limitations of claim 1 above. Suminosuke does not expressly teach that the shell polymer is a non-crosslinked or crosslinked polymer comprising at least one of the monomers included in claim 6.
Fan teaches a separator including a porous substrate and a first coating disposed on at least a surface of the porous substrate, wherein the first coating includes a first polymer binder and first inorganic particles, further teaching that the first polymer binder includes core-shell structured particles (¶ [0005], Ln. 1-6). The porous substrate includes a polymer film, multilayer polymer film, or a non-woven fabric formed of polymers (porous polymer substrate) (¶ [0023], Ln. 1-3). Fan teaches that the core of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of ethyl acrylate, butyl acrylate, ethyl methacrylate, styrene, chlorostyrene, fluorobenzene ethylene, methylstyrene, acrylic acid, methacrylic acid, maleic acid, and any combination thereof, and that the shell of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene, chlorostyrene, fluorostyrene, methylstyrene, acrylonitrile, methyl acrylonitrile, and any combination thereof (¶ [0024], Ln. 1-15). Fan teaches that by adopting the core-shell particle structure, the uniformity of the particles is improved and, in the post-heating process, the shell of the first polymer binder may be softened first, and then the core of the first polymer binder may have bonding function (¶ [0024], Ln. 15-21).
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 shell polymer of Suminosuke to include a polymer taught by Fan, such as methyl methacrylate. In polymerizing methyl methacrylate, a polymethyl methacrylate shell polymer would be formed. One of ordinary skill in the art would be motivated to modify the shell polymer based on the teachings of Fan such that the shell of the first polymer binder may be softened first, and then the core of the first polymer binder may have bonding function.
Regarding claim 11, Suminosuke teaches all of the limitations of claim 1 above. Suminosuke does not expressly teach that the binder polymer comprises at least one of the polymers listed in claim 11.
Fan teaches that the first coating further includes an auxiliary binder, which may be selected from the group consisting of copolymer of vinylidene fluoride-hexafluoropropylene, copolymer of vinylidene fluoride-trichloroethylene, polystyrene, polyacrylate, polyacrylic acid, polyacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyacetic acid vinyl ester, copolymer of ethylene-vinyl acetate, polyimide, polyethylene oxide, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl amylopectin, cyanoethyl poly copolymerization of vinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, amylopectin, carboxymethyl cellulose, sodium carboxymethyl cellulose, lithium carboxymethyl cellulose, acrylonitrile-styrene-butadiene polymers, polyphthalamide, polyvinyl alcohol, styrene-butadiene copolymers, polyvinylidene fluoride, and any combination thereof (¶ [0028], Ln. 4-19). Fan teaches that the auxiliary binder helps to improve a bonding performance of the first coating (¶ [0028], Ln. 26-27).
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 binder polymer of Suminosuke to comprise one of the auxiliary binder polymers taught by Fan. One of ordinary skill in the art would find it obvious to select any polymer taught by Fan, including a copolymer of vinylidene fluoride-hexafluoropropylene, a copolymer of vinylidene fluoride-trichloroethylene, a polyacrylate, polyacrylonitrile, polyvinylpyrrolidone, a copolymer of ethylene-vinyl acetate, polyethylene oxide, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl poly copolymerization of vinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, or carboxymethyl cellulose. One of ordinary skill in the art would be motivated to include one of these polymers in the adhesive layer of Suminosuke in order to improve the bonding performance of the adhesive layer and the separator.
Regarding claim 15, Suminosuke teaches all of the limitations of claim 1 above. Suminosuke does not expressly teach that the shell polymer comprises polymethyl methacrylate-co-n-butyl acrylate.
Fan teaches a separator including a porous substrate and a first coating disposed on at least a surface of the porous substrate, wherein the first coating includes a first polymer binder and first inorganic particles, further teaching that the first polymer binder includes core-shell structured particles (¶ [0005], Ln. 1-6). The porous substrate includes a polymer film, multilayer polymer film, or a non-woven fabric formed of polymers (porous polymer substrate) (¶ [0023], Ln. 1-3). Fan teaches that the core of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of ethyl acrylate, butyl acrylate, ethyl methacrylate, styrene, chlorostyrene, fluorobenzene ethylene, methylstyrene, acrylic acid, methacrylic acid, maleic acid, and any combination thereof, and that the shell of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene, chlorostyrene, fluorostyrene, methylstyrene, acrylonitrile, methyl acrylonitrile, and any combination thereof (¶ [0024], Ln. 1-15). In the first polymer binder of Example 1, Fan teaches that the shell includes a copolymer of methyl methacrylate and methyl styrene (¶ [0079], Ln. 1-3). Fan teaches that by adopting the core-shell particle structure, the uniformity of the particles is improved and, in the post-heating process, the shell of the first polymer binder may be softened first, and then the core of the first polymer binder may have bonding function (¶ [0024], Ln. 15-21).
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 shell polymer of Suminosuke to include a polymer taught by Fan. As Fan teaches methyl methacrylate in the list of possible monomers and in the example, one of ordinary skill in the art would find it obvious to include methyl methacrylate in the shell polymer. Additionally, as Fan teaches butyl acrylate as a monomer that can be used to form the shell of the first polymer binder, one of ordinary skill in the art would find it obvious to include butyl acrylate in the shell polymer. In polymerizing methyl methacrylate and butyl acrylate, the resulting shell polymer would comprise polymethyl methacrylate-co-n-butyl acrylate. One of ordinary skill in the art would be motivated to modify the shell polymer based on the teachings of Fan such that the shell of the first polymer binder may be softened first, and then the core of the first polymer binder may have bonding function.
Regarding claim 16, Suminosuke in view of Fan teaches all of the limitations of claim 15 above. Suminosuke further teaches that the core polymer preferably contains a crosslinkable monomer unit so that the swelling degree can be easily controlled (¶ [0047], Ln. 1-7) and that acrylic acid is included in the list of possible monomers used to produce a core polymer with the desired swelling degree (¶ [0044], Ln. 1-7). Suminosuke does not expressly teach that the core polymer comprises polyacrylic acid crosslinked polymer.
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 core polymer of Suminosuke to crosslink acrylic acid, forming a crosslinked polyacrylic acid, based on the teachings of Suminosuke. As the reference teaches that it is preferred to include crosslinkable monomers in the core portion and provides acrylic acid in the list of possible monomers, one of ordinary skill in the art would find it obvious to include polyacrylic acid crosslinked polymer in the core polymer. One would be motivated to include crosslinked acrylic acid monomers in order to control the swelling degree.
Claims 17-19 are rejected under 35 U.S.C. 103 as being unpatentable over Suminosuke, et al. (JP 2015/088253 A) in view of Fan (US 2021/0234233 A1).
Regarding claim 17, Suminosuke teaches a separator for a lithium ion secondary battery, comprising a separator substrate and an adhesive layer (coating layer), wherein the adhesive layer contains a particulate polymer, and the particulate polymer has a core-shell structure (¶ [0010], Ln. 14-16). Examples of separator substrates include porous substrates made of resins containing polyolefins such as polyethylene, polypropylene, polybutene, and polyvinyl chloride, mixtures thereof, and copolymers thereof (porous polymer substrate having a plurality of pores) (¶ [0135], Ln. 1-3). Suminosuke teaches that pores are provided in the adhesive layer to increase ion diffusibility (porous coating layer) (¶ [0102], Ln. 2-3). The adhesive layer preferably further contains a binder for the in addition to the particulate polymer (¶ [0087], Ln. 1-2). Suminosuke teaches that by using the binder, the particulate polymer can be bonded to each other both in a state where it is swollen in the electrolytic solution and in a state where it is not swollen (binder polymer disposed partially or totally on a surface of the core-shell polymer particles and core-shell polymer particles are interconnected and fixed) (¶ [0087], Ln. 3-5).
Suminosuke teaches that the core portion of the particulate polymer is made of a polymer having a swelling degree in an electrolytic solution of 5 to 30 times (first polymer absorbs an electrolyte in an amount corresponding to 2-50 times a weight of the first polymer) and the shell portion is made of a polymer (second polymer) having a swelling degree in an electrolytic solution of more than 1 to 4 and preferably 1.2 to 3 times (¶ [0055], Ln. 4-6), overlapping the claimed range of 2 times or less. 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)). Additionally, Suminosuke teaches that the glass transition temperature of the shell polymer is preferably 70 °C or higher (¶ [0067], Ln. 1-3). The melting point temperature is higher than the glass transition temperature. A general rule of thumb is that the glass transition temperature of a polymer is 2/3 the melting point temperature, resulting in a general melting point temperature of 104 °C for the shell polymer of Suminosuke (melting point of 80 °C or higher). Suminosuke teaches that the polymer of the shell portion preferably includes an aromatic vinyl monomer (¶ [0060], Ln. 1) and additionally preferably contains amide monomer units (amide-based polymer) (¶ [0064], Ln. 1-9), further teachings that the polymer may contain crosslinkable monomer units (¶ [0062], Ln. 1). For example, the shell polymer of example 1 includes styrene and acrylamide (¶ [0224], Ln. 1).
Suminosuke teaches that the adhesive may contain non-conductive particles, which increase the mechanical strength of the adhesive layer (¶ [0114], Ln. 1-8). In referencing the non-conductive particles, Suminosuke points to the disclosure regarding non-conductive particles included in the porous membrane. The non-conductive particles may be inorganic or organic, with inorganic particles being preferred (¶ [0140], Ln. 1-6). As examples of inorganic particles, Suminosuke teaches oxide particles including titanium oxide, aluminum oxide, aluminum oxide hydrate, magnesium oxide, and magnesium hydroxide (¶ [0140], Ln. 14-16). Suminosuke does not expressly teach an embodiment in which inorganic particles are included in the adhesive layer.
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 adhesive layer of Suminosuke to include inorganic particles such as titanium oxide. One of ordinary skill in the art would find it obvious to include titanium oxide in the adhesive layer as Suminosuke teaches the inclusion of non-conductive particles in the adhesive layer, and further teaches preferred examples of non-conductive particles including inorganic oxide particles, and specifically titanium oxide. One of ordinary skill in the art would be motivated to include inorganic oxide particles in the adhesive layer in order to increase the mechanical strength.
Suminosuke does not expressly teach that the shell polymer is a non-crosslinked or crosslinked polymer comprising at least one of the monomers included in claim 17.
Fan teaches a separator including a porous substrate and a first coating disposed on at least a surface of the porous substrate, wherein the first coating includes a first polymer binder and first inorganic particles, further teaching that the first polymer binder includes core-shell structured particles (¶ [0005], Ln. 1-6). The porous substrate includes a polymer film, multilayer polymer film, or a non-woven fabric formed of polymers (porous polymer substrate) (¶ [0023], Ln. 1-3). Fan teaches that the core of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of ethyl acrylate, butyl acrylate, ethyl methacrylate, styrene, chlorostyrene, fluorobenzene ethylene, methylstyrene, acrylic acid, methacrylic acid, maleic acid, and any combination thereof, and that the shell of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene, chlorostyrene, fluorostyrene, methylstyrene, acrylonitrile, methyl acrylonitrile, and any combination thereof (¶ [0024], Ln. 1-15). Fan teaches that by adopting the core-shell particle structure, the uniformity of the particles is improved and, in the post-heating process, the shell of the first polymer binder may be softened first, and then the core of the first polymer binder may have bonding function (¶ [0024], Ln. 15-21).
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 shell polymer of Suminosuke to include a polymer taught by Fan, such as methyl methacrylate. In polymerizing methyl methacrylate, a polymethyl methacrylate shell polymer would be formed. One of ordinary skill in the art would be motivated to modify the shell polymer based on the teachings of Fan such that the shell of the first polymer binder may be softened first, and then the core of the first polymer binder may have bonding function.
Regarding claim 18, Suminosuke teaches a separator for a lithium ion secondary battery, comprising a separator substrate and an adhesive layer (coating layer), wherein the adhesive layer contains a particulate polymer, and the particulate polymer has a core-shell structure (¶ [0010], Ln. 14-16). Examples of separator substrates include porous substrates made of resins containing polyolefins such as polyethylene, polypropylene, polybutene, and polyvinyl chloride, mixtures thereof, and copolymers thereof (porous polymer substrate having a plurality of pores) (¶ [0135], Ln. 1-3). Suminosuke teaches that pores are provided in the adhesive layer to increase ion diffusibility (porous coating layer) (¶ [0102], Ln. 2-3). The adhesive layer preferably further contains a binder for the in addition to the particulate polymer (¶ [0087], Ln. 1-2). Suminosuke teaches that by using the binder, the particulate polymer can be bonded to each other both in a state where it is swollen in the electrolytic solution and in a state where it is not swollen (binder polymer disposed partially or totally on a surface of the core-shell polymer particles and core-shell polymer particles are interconnected and fixed) (¶ [0087], Ln. 3-5).
Suminosuke teaches that the core portion of the particulate polymer is made of a polymer having a swelling degree in an electrolytic solution of 5 to 30 times (first polymer) and the shell portion is made of a polymer (second polymer) having a swelling degree in an electrolytic solution of more than 1 to 4 and preferably 1.2 to 3 times (¶ [0055], Ln. 4-6). Additionally, Suminosuke teaches that the glass transition temperature of the shell polymer is preferably 70 °C or higher (¶ [0067], Ln. 1-3). The melting point temperature is higher than the glass transition temperature. A general rule of thumb is that the glass transition temperature of a polymer is 2/3 the melting point temperature, resulting in a general melting point temperature of 104 °C for the shell polymer of Suminosuke (melting point of 80 °C or higher).
Suminosuke teaches that the adhesive may contain non-conductive particles, which increase the mechanical strength of the adhesive layer (¶ [0114], Ln. 1-8). In referencing the non-conductive particles, Suminosuke points to the disclosure regarding non-conductive particles included in the porous membrane. The non-conductive particles may be inorganic or organic, with inorganic particles being preferred (¶ [0140], Ln. 1-6). As examples of inorganic particles, Suminosuke teaches oxide particles including titanium oxide, aluminum oxide, aluminum oxide hydrate, magnesium oxide, and magnesium hydroxide (¶ [0140], Ln. 14-16). Suminosuke does not expressly teach an embodiment in which inorganic particles are included in the adhesive layer.
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 adhesive layer of Suminosuke to include inorganic particles such as titanium oxide. One of ordinary skill in the art would find it obvious to include titanium oxide in the adhesive layer as Suminosuke teaches the inclusion of non-conductive particles in the adhesive layer, and further teaches preferred examples of non-conductive particles including inorganic oxide particles, and specifically titanium oxide. One of ordinary skill in the art would be motivated to include inorganic oxide particles in the adhesive layer in order to increase the mechanical strength.
Suminosuke does not expressly teach that the shell polymer comprises polymethyl methacrylate-co-n-butyl acrylate.
Fan teaches a separator including a porous substrate and a first coating disposed on at least a surface of the porous substrate, wherein the first coating includes a first polymer binder and first inorganic particles, further teaching that the first polymer binder includes core-shell structured particles (¶ [0005], Ln. 1-6). The porous substrate includes a polymer film, multilayer polymer film, or a non-woven fabric formed of polymers (porous polymer substrate) (¶ [0023], Ln. 1-3). Fan teaches that the core of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of ethyl acrylate, butyl acrylate, ethyl methacrylate, styrene, chlorostyrene, fluorobenzene ethylene, methylstyrene, acrylic acid, methacrylic acid, maleic acid, and any combination thereof, and that the shell of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene, chlorostyrene, fluorostyrene, methylstyrene, acrylonitrile, methyl acrylonitrile, and any combination thereof (¶ [0024], Ln. 1-15). In the first polymer binder of Example 1, Fan teaches that the shell includes a copolymer of methyl methacrylate and methyl styrene (¶ [0079], Ln. 1-3). Fan teaches that by adopting the core-shell particle structure, the uniformity of the particles is improved and, in the post-heating process, the shell of the first polymer binder may be softened first, and then the core of the first polymer binder may have bonding function (¶ [0024], Ln. 15-21).
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 shell polymer of Suminosuke to include a polymer taught by Fan. As Fan teaches methyl methacrylate in the list of possible monomers and in the example, one of ordinary skill in the art would find it obvious to include methyl methacrylate in the shell polymer. Additionally, as Fan teaches butyl acrylate as a monomer that can be used to form the shell of the first polymer binder, one of ordinary skill in the art would find it obvious to include butyl acrylate in the shell polymer. In polymerizing methyl methacrylate and butyl acrylate, the resulting shell polymer would comprise polymethyl methacrylate-co-n-butyl acrylate. One of ordinary skill in the art would be motivated to modify the shell polymer based on the teachings of Fan such that the shell of the first polymer binder may be softened first, and then the core of the first polymer binder may have bonding function.
Regarding claim 19, Suminosuke teaches a separator for a lithium ion secondary battery, comprising a separator substrate and an adhesive layer (coating layer), wherein the adhesive layer contains a particulate polymer, and the particulate polymer has a core-shell structure (¶ [0010], Ln. 14-16). Examples of separator substrates include porous substrates made of resins containing polyolefins such as polyethylene, polypropylene, polybutene, and polyvinyl chloride, mixtures thereof, and copolymers thereof (porous polymer substrate having a plurality of pores) (¶ [0135], Ln. 1-3). Suminosuke teaches that pores are provided in the adhesive layer to increase ion diffusibility (porous coating layer) (¶ [0102], Ln. 2-3). The adhesive layer preferably further contains a binder for the in addition to the particulate polymer (¶ [0087], Ln. 1-2). Suminosuke teaches that by using the binder, the particulate polymer can be bonded to each other both in a state where it is swollen in the electrolytic solution and in a state where it is not swollen (binder polymer disposed partially or totally on a surface of the core-shell polymer particles and core-shell polymer particles are interconnected and fixed) (¶ [0087], Ln. 3-5).
Suminosuke teaches that the core portion of the particulate polymer is made of a polymer having a swelling degree in an electrolytic solution of 5 to 30 times (first polymer) and the shell portion is made of a polymer (second polymer) having a swelling degree in an electrolytic solution of more than 1 to 4 and preferably 1.2 to 3 times (¶ [0055], Ln. 4-6). Additionally, Suminosuke teaches that the glass transition temperature of the shell polymer is preferably 70 °C or higher (¶ [0067], Ln. 1-3). The melting point temperature is higher than the glass transition temperature. A general rule of thumb is that the glass transition temperature of a polymer is 2/3 the melting point temperature, resulting in a general melting point temperature of 104 °C for the shell polymer of Suminosuke (melting point of 80 °C or higher).
Suminosuke teaches that the adhesive may contain non-conductive particles, which increase the mechanical strength of the adhesive layer (¶ [0114], Ln. 1-8). In referencing the non-conductive particles, Suminosuke points to the disclosure regarding non-conductive particles included in the porous membrane. The non-conductive particles may be inorganic or organic, with inorganic particles being preferred (¶ [0140], Ln. 1-6). As examples of inorganic particles, Suminosuke teaches oxide particles including titanium oxide, aluminum oxide, aluminum oxide hydrate, magnesium oxide, and magnesium hydroxide (¶ [0140], Ln. 14-16). Suminosuke does not expressly teach an embodiment in which inorganic particles are included in the adhesive layer.
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 adhesive layer of Suminosuke to include inorganic particles such as titanium oxide. One of ordinary skill in the art would find it obvious to include titanium oxide in the adhesive layer as Suminosuke teaches the inclusion of non-conductive particles in the adhesive layer, and further teaches preferred examples of non-conductive particles including inorganic oxide particles, and specifically titanium oxide. One of ordinary skill in the art would be motivated to include inorganic oxide particles in the adhesive layer in order to increase the mechanical strength.
Suminosuke does not expressly teach that the core polymer comprises polyacrylic acid crosslinked polymer.
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 core polymer of Suminosuke to crosslink acrylic acid, forming a crosslinked polyacrylic acid, based on the teachings of Suminosuke. As the reference teaches that it is preferred to include crosslinkable monomers in the core portion and provides acrylic acid in the list of possible monomers, one of ordinary skill in the art would find it obvious to include polyacrylic acid crosslinked polymer in the core polymer. One would be motivated to include crosslinked acrylic acid monomers in order to control the swelling degree.
Suminosuke does not expressly teach that the shell polymer comprises polymethyl methacrylate-co-n-butyl acrylate.
Fan teaches a separator including a porous substrate and a first coating disposed on at least a surface of the porous substrate, wherein the first coating includes a first polymer binder and first inorganic particles, further teaching that the first polymer binder includes core-shell structured particles (¶ [0005], Ln. 1-6). The porous substrate includes a polymer film, multilayer polymer film, or a non-woven fabric formed of polymers (porous polymer substrate) (¶ [0023], Ln. 1-3). Fan teaches that the core of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of ethyl acrylate, butyl acrylate, ethyl methacrylate, styrene, chlorostyrene, fluorobenzene ethylene, methylstyrene, acrylic acid, methacrylic acid, maleic acid, and any combination thereof, and that the shell of the first polymer binder is formed by polymerizing of monomers selected from a group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, ethylene, chlorostyrene, fluorostyrene, methylstyrene, acrylonitrile, methyl acrylonitrile, and any combination thereof (¶ [0024], Ln. 1-15). In the first polymer binder of Example 1, Fan teaches that the shell includes a copolymer of methyl methacrylate and methyl styrene (¶ [0079], Ln. 1-3). Fan teaches that by adopting the core-shell particle structure, the uniformity of the particles is improved and, in the post-heating process, the shell of the first polymer binder may be softened first, and then the core of the first polymer binder may have bonding function (¶ [0024], Ln. 15-21).
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 shell polymer of Suminosuke to include a polymer taught by Fan. As Fan teaches methyl methacrylate in the list of possible monomers and in the example, one of ordinary skill in the art would find it obvious to include methyl methacrylate in the shell polymer. Additionally, as Fan teaches butyl acrylate as a monomer that can be used to form the shell of the first polymer binder, one of ordinary skill in the art would find it obvious to include butyl acrylate in the shell polymer. In polymerizing methyl methacrylate and butyl acrylate, the resulting shell polymer would comprise polymethyl methacrylate-co-n-butyl acrylate. One of ordinary skill in the art would be motivated to modify the shell polymer based on the teachings of Fan such that the shell of the first polymer binder may be softened first, and then the core of the first polymer binder may have bonding function.
Response to Arguments
Response-Claim Rejections – 35 U.S.C. 103
In light of the Applicant’s amendments to claim 1 and cancellation of claims 5 and 10, the previous rejections of claims 1, 3, 7-9, and 12-14 under 35 U.S.C. 103 over Suminosuke, et al. (JP 2015/088253 A) have been modified above.
The Applicant's arguments filed April 27, 2026 with respect to Suminosuke have been fully considered but they are not persuasive. The Applicant argues that Suminosuke does not teach a shell polymer (second polymer) comprising at least one selected from the group consisting of an acrylate polymer, an ester-based polymer, an olefin-based polymer, a vinyl fluoride-based polymer, a fluoroolefin-based polymer, a urethane-based polymer, a phenolic resin, an amide-based polymer, and an aramid-based polymer; that the core and shell of the particulate polymer taught by Suminosuke functions differently from the core and shell polymer particles of the instant invention; and that Suminosuke does not contemplate the unexpected advantages resulting from the claimed separator.
With respect to the argument, see pages 1-2 of the remarks, that Suminosuke does not teach a shell polymer (second polymer) comprising at least one selected from the group consisting of an acrylate polymer, an ester-based polymer, an olefin-based polymer, a vinyl fluoride-based polymer, a fluoroolefin-based polymer, a urethane-based polymer, a phenolic resin, an amide-based polymer, and an aramid-based polymer, this argument is not persuasive. Suminosuke teaches that the shell polymer preferably contains amide monomer units (amide-based polymer) (¶ [0064], Ln. 1-9), specifically teaching that the shell polymer of example 1 includes styrene and acrylamide (¶ [0224], Ln. 1). Thus, Suminosuke teaches a shell polymer comprising an amide-based polymer. Further, it is noted that styrene and acrylamide both contain an olefin (olefin-based polymer).
With respect to the argument, see pages 2-3 of the remarks, that the core and shell of the particulate polymer taught by Suminosuke functions differently from the core and shell polymer particles of the instant invention, this argument is not persuasive. It is noted that the feature which the Applicant relies upon, the core-shell structure of the polymer particles, is taught by the reference applied. The reference teaches a core-shell particulate polymer structure meeting the melting point limitations and swelling degree limitations of the claimed polymer particles. In response to the Applicant's argument that the claimed separator delays or prevents ignition or thermal runaway, 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).
With respect to the argument, see page 3 of the remarks, that Suminosuke does not contemplate the unexpected advantages resulting from the claimed separator, this argument is not persuasive. As stated above, 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). Further, in the event that the Applicant intends to present a showing of unexpected results, a detailed description of the reasons and evidence supporting Applicant’s position is necessary. See MPEP 716.02(b). Applicants may compare the claimed invention with prior art that is more closely related to the invention than the prior art relied upon by the examiner. See MPEP 716.02(e).
Conclusion
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