Electricity storage device binder aqueous solution, electricity storage device slurry, electricity storage device electrode, electricity storage device separator, electricity storage device separator / electrode laminate, and electricity storage device

Abstract

An aqueous binder solution for an electricity storage device, the aqueous binder solution containing a water-soluble polymer, (meth) acrylamide, and (meth) acrylonitrile, the water-soluble polymer containing 0.01% by mass to 1% by mass of a polymerization initiator unit, the (meth) acrylamide and the (meth) acrylonitrile being contained in the water-soluble polymer, the (meth) acrylamide being contained in the (meth) acrylonitrile being contained in the (meth) acrylonitrile; the content of the (meth) acrylamide is at least 0.01 mass ppm and less than 1000 mass ppm.

Description

Technical Field

[0001] The present disclosure relates to an aqueous solution of an electric storage device binder, an electric storage device slurry, an electric storage device electrode, an electric storage device separator, an electric storage device separator / electrode laminate, and an electric storage device. Background Art

[0002] The applicant is studying a method of using a water-soluble polymer as a binder for an electrical storage device. Prior art literature Patent Literature

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-006333 Summary of the invention Technical problem to be solved by the invention

[0004] The technical problem to be solved by the present invention is to provide an aqueous solution of a power storage device binder for producing a power storage device having excellent pencil hardness, breaking strength, first coulomb efficiency, and discharge capacity retention rate. Technical means of solving problems

[0005] The present inventors have found that the above-mentioned problems can be solved by using specific components.

[0006] The following items are provided according to the present disclosure. (Item 1) An aqueous solution of an adhesive for an electrical storage device, The storage device binder aqueous solution comprises: a water-soluble polymer, (meth)acrylamide and (meth)acrylonitrile, The water-soluble polymer contains 0.01% to 1% by mass of a polymerization initiator unit. The content of the (meth)acrylamide is 0.01 ppm by mass or more and less than 1000 ppm by mass relative to the water-soluble polymer. (Item 2) A slurry for an electric storage device, The electrical storage device slurry comprises: a water-soluble polymer, (meth)acrylamide, (meth)acrylonitrile and water. The water-soluble polymer contains 0.01% to 1% by mass of a polymerization initiator unit. The content of the (meth)acrylamide is 0.01 ppm by mass or more and less than 1000 ppm by mass relative to the water-soluble polymer. (Item 3) The electrical storage device slurry according to the above item contains an electrode active material. (Item 4) The electrical storage device slurry according to the above item contains non-conductive particles. (Item 5) An electric storage device electrode comprising a dried product of the electric storage device slurry according to any one of the above items on a current collector. (Item 6) An electric storage device separator comprising a dried product of the electric storage device slurry according to any one of the above items on a substrate. (Item 7) An electrical storage device separator / electrode laminate having a dried product of the electrical storage device slurry according to any one of the above items on an active material side of an electrode. (Item 8) An electric storage device comprises the electric storage device electrode described in the above item. (Item 9) An electric storage device comprises the electric storage device separator according to the above item. (Item 10) An electric storage device comprises the electric storage device separator / electrode stack according to the above item. (Project A1) The electrical storage device binder aqueous solution or the electrical storage device slurry according to the above item, wherein the water-soluble polymer contains 1 mol % to 99.998 mol % of (meth)acrylamide units. (Project A2) The electrical storage device binder aqueous solution or the electrical storage device slurry according to the above item, wherein the water-soluble polymer contains 10 mol % to 99.9 mol % of (meth)acrylamide units. (Item A3) The electrical storage device binder aqueous solution or the electrical storage device slurry according to the above item, wherein the water-soluble polymer contains 20 mol % or more and less than 99.65 mol % of (meth)acrylamide units. (Item A4) The electrical storage device binder aqueous solution or the electrical storage device slurry according to the above item, wherein the water-soluble polymer contains 55 mol % to 95 mol % of (meth)acrylamide units. (Item A5) The electrical storage device binder aqueous solution or the electrical storage device slurry according to the above item, wherein the water-soluble polymer contains 1% by mass to 99.998% by mass of (meth)acrylamide units. (Item A6) The electrical storage device binder aqueous solution or the electrical storage device slurry according to the above item, wherein the water-soluble polymer contains 10% by mass to 99.9% by mass of (meth)acrylamide units. (Item A7) The electrical storage device binder aqueous solution or the electrical storage device slurry according to the above item, wherein the water-soluble polymer contains 20 mass % or more and less than 99.65 mass % of (meth)acrylamide units. (Item A8) The electrical storage device binder aqueous solution or the electrical storage device slurry according to the above item, wherein the water-soluble polymer contains 55% by mass to 95% by mass of (meth)acrylamide units. (Item A9) The electrical storage device binder aqueous solution or the electrical storage device slurry according to the above item, wherein the water-soluble polymer contains 0 mol % to 80 mol % of N-substituted mono(meth)acrylamide units. (Item A10) The electrical storage device binder aqueous solution or the electrical storage device slurry according to the above item, wherein the water-soluble polymer contains 1 mol % to 70 mol % of N-substituted mono(meth)acrylamide units. (Item A11) The electrical storage device binder aqueous solution or the electrical storage device slurry according to the above item, wherein the water-soluble polymer contains 0% by mass to 80% by mass of N-substituted mono(meth)acrylamide units. (Item A12) The electrical storage device binder aqueous solution or the electrical storage device slurry according to the above item, wherein the water-soluble polymer contains 1% by mass to 70% by mass of N-substituted mono(meth)acrylamide units. (Item A13) In the electrical storage device binder aqueous solution or the electrical storage device slurry according to the above item, the water-soluble polymer contains N-monosubstituted mono(meth)acrylamide units, and the N-monosubstituted mono(meth)acrylamide is represented by the following structural formula.

Chemical m1

Chemical formula d1

[0007] One or more of the features described may also be provided in further combinations than those explicitly indicated. Beneficial Effects

[0008] By using the electrical storage device binder aqueous solution of the present disclosure, it is possible to produce an electrical storage device having excellent pencil hardness, breaking strength, initial coulombic efficiency, and discharge capacity retention rate. DETAILED DESCRIPTION

[0009] In the whole of the present disclosure, the range of the numerical values ​​of each physical property value, content, etc. can be set appropriately (for example, selected from the values ​​described in the following items). Specifically, with respect to the numerical value α, when A3, A2, and A1 (set as A3>A2>A1) are given as examples, the range of the numerical value α can be, for example, less than A3, less than A2, less than A3, less than A2, greater than A1, greater than A2, greater than A1, greater than A2, A1-A2 (Above A1 and below A2), A1-A3, A2-A3, greater than A1 and less than A3, greater than A1 and less than A2, greater than A2 and less than A3, greater than A1 and less than A3, greater than A1 and less than A2, greater than A2 and less than A3, greater than A1 and less than A3, greater than A1 and less than A2, greater than A2 and less than A3, greater than A1 and less than A3, greater than A1 and less than A3, greater than A2 and less than A3, greater than A1 and less than A3, greater than A1 and less than A2, greater than A2 and less than A3, greater than A1 and less than A3, greater than A1 and less than A2, greater than A2 and less than A3, greater than A1 and less than A3, greater than A1 and less than A2, greater than A2 and less than A3, etc.

[0010] As long as the problems to be solved by the present invention are solved, the components, conditions, quantities, etc. are not limited to those described in the specification.

[0011] "αβ amount (A / B)" means the β amount (α) of A relative to 100α% of B. Examples of α include mass %, mole %, and parts by mass. Examples of β amount include content and usage amount.

[0012] “γ ratio (A / B)” means the γ ratio calculated by the formula “A÷B”. Examples of the γ ratio include mass ratio and molar ratio.

[0013] In the present disclosure, "nonvolatile matter" refers to the total mass of components other than organic solvent and water. In one embodiment, "nonvolatile matter of object A" refers to the total mass of components remaining when 1 g of object A is heated at 105°C to a constant weight.

[0014] “(Meth)acrylic acid” means “at least one selected from the group consisting of acrylic acid and methacrylic acid”. “(Meth)acrylate” means “at least one selected from the group consisting of acrylate and methacrylate”. “(Meth)acryloyl” means “at least one selected from the group consisting of acryloyl and methacryloyl”.

[0015] Examples of the alkyl group include a linear alkyl group, a branched alkyl group, and a cycloalkyl group.

[0016] Examples of the straight-chain alkyl group include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, and n-decyl.

[0017] The "branched alkyl group" refers to a group in which at least one hydrogen atom of a linear alkyl group is substituted with an alkyl group and the group does not have a ring structure.

[0018] Examples of the branched alkyl group include isopropyl, diethylpentyl, trimethylbutyl, trimethylpentyl, and trimethylhexyl.

[0019] Examples of the cycloalkyl group include a monocyclic cycloalkyl group, a bridged ring cycloalkyl group, a condensed ring cycloalkyl group, etc. Furthermore, a group in which at least one hydrogen atom of a cycloalkyl group is substituted by an alkyl group is also considered to be a cycloalkyl group.

[0020] "Single ring" refers to a ring structure formed by covalent bonds of carbon and without a bridge structure inside. "Fused ring" refers to a ring structure in which two or more single rings share two atoms (i.e., only one side of each ring is shared (fused) with each other). "Bridged ring" refers to a ring structure in which two or more single rings share three or more atoms.

[0021] Examples of the monocyclic cycloalkyl group include cyclopentyl, cyclohexyl, cycloheptyl, cyclodecyl, and 3,5,5-trimethylcyclohexyl.

[0022] Examples of the bridged cycloalkyl group include tricyclodecanyl, adamantyl, and norbornyl.

[0023] In addition, the alkyl group also includes a group in which a linear alkyl group, a branched alkyl group, and a cycloalkyl group are combined. Examples of such a group in which a linear alkyl group, a branched alkyl group, and a cycloalkyl group are combined include a cycloalkylalkyl group and the like.

[0024] Examples of the salt include inorganic salts and organic salts.

[0025] "Inorganic salt" refers to a salt wherein the cationic portion is a metal cation.

[0026] Examples of the inorganic salt include sodium salt, lithium salt, calcium salt and the like.

[0027] Examples of the organic salt include ammonium salts and amine salts.

[0028] [Electric storage device binder aqueous solution: aqueous solution] The present invention relates to an aqueous solution of an electrical storage device binder. The storage device binder aqueous solution comprises: a water-soluble polymer, (meth)acrylamide and (meth)acrylonitrile, wherein the water-soluble polymer comprises 0.01 mass % to 1 mass % of a polymerization initiator unit, The content of the (meth)acrylamide is 0.01 ppm by mass or more and less than 1000 ppm by mass relative to the water-soluble polymer.

[0029] <Water-soluble polymer: polymer> The water-soluble polymers may be used alone or in combination of two or more.

[0030] The term "water-soluble" means that when 0.5 g of the compound is dissolved in 100 g of water at 25°C, the water-insoluble component is less than 0.5% by mass (less than 2.5 mg).

[0031] Examples of the water-insoluble component include less than 0.5 mass %, less than 0.4 mass %, less than 0.3 mass %, less than 0.2 mass %, less than 0.1 mass %, and 0 mass %.

[0032] ((Meth)acrylamide) The (meth)acrylamide may be used alone or in combination of two or more.

[0033] The mole % content ((meth) acrylamide unit / water-soluble polymer) includes, for example, 99.998 mol%, 99.99 mol%, 95 mol%, 90 mol%, 85 mol%, 80 mol%, 75 mol%, 70 mol%, 65 mol%, 60 mol%, 55 mol%, 50 mol%, 45 mol%, 40 mol%, 35 mol%, 30 mol%, 25 mol%, 20 mol%, 15 mol%, 10 mol%, 9 mol%, 5 mol%, 4 mol%, 2 mol%, 1 mol%, etc. In one embodiment, the content preferably includes 1 mol% to 99.998 mol%, more preferably 10 mol% to 99.9 mol%, further preferably 20 mol% or more and less than 99.65 mol%, and particularly preferably 55 mol% to 95 mol%. The preferred reasons include, for example, improved dispersibility and improved storage stability.

[0034] Mass% content ((meth) acrylamide unit / water-soluble polymer) for example includes 99.998 mass%, 99.99 mass%, 95 mass%, 90 mass%, 85 mass%, 80 mass%, 75 mass%, 70 mass%, 65 mass%, 60 mass%, 55 mass%, 50 mass%, 45 mass%, 40 mass%, 35 mass%, 30 mass%, 25 mass%, 20 mass%, 15 mass%, 10 mass%, 9 mass%, 5 mass%, 4 mass%, 2 mass%, 1 mass%, etc. In one embodiment, the content preferably includes 1 mass% to 99.998 mass%, more preferably includes 10 mass% to 99.9 mass%, further preferably includes 20 mass% or more and less than 99 mass%, and particularly preferably includes 55 mass% to 95 mass%. The preferred reasons include, for example, improved dispersibility and improved storage stability.

[0035] (N-substituted mono(meth)acrylamide) In one embodiment, the water-soluble polymer may optionally contain an N-substituted mono(meth)acrylamide unit. The N-substituted mono(meth)acrylamide may be used alone or in combination of two or more.

[0036] "N-substituted mono(meth)acrylamide" refers to a compound having one (meth)acrylamide group in which one or more hydrogen atoms on nitrogen are substituted with groups other than hydrogen atoms. [Chemistry 1] (Where R 1 is a hydrogen atom or a methyl group.)

[0037] Examples of N-substituted mono(meth)acrylamide include N-monosubstituted mono(meth)acrylamide and N,N-disubstituted mono(meth)acrylamide.

[0038] In one embodiment, N-monosubstituted mono(meth)acrylamide is represented by the following structural formula.

Chemical m1

[0039] Examples of N-monosubstituted mono(meth)acrylamide include monoalkyl(meth)acrylamide, N-hydroxymethyl(meth)acrylamide, hydroxyethyl(meth)acrylamide, dimethylaminopropyl(meth)acrylamide, diacetone(meth)acrylamide, dimethylaminopropyl(meth)acrylamide methyl chloride quaternary ammonium salt, and dimethylaminoethyl(meth)acrylate benzyl chloride quaternary ammonium salt.

[0040] “Monoalkyl (meth)acrylamide” refers to a compound in which one hydrogen atom directly bonded to the nitrogen atom of (meth)acrylamide is substituted with an unsubstituted alkyl group.

[0041] Examples of the monoalkyl (meth)acrylamide include N-methyl (meth)acrylamide, N-ethyl (meth)acrylamide, and N-propyl (meth)acrylamide.

[0042] In one embodiment, N,N-disubstituted mono(meth)acrylamide is represented by the following structural formula.

Chemistry d1

[0043] Examples of N-disubstituted mono(meth)acrylamide include dialkyl(meth)acrylamide and (meth)acryloylmorpholine.

[0044] “Dialkyl (meth)acrylamide” refers to a compound in which two hydrogen atoms directly bonded to the nitrogen atom of (meth)acrylamide are substituted with unsubstituted alkyl groups.

[0045] Examples of the dialkyl (meth)acrylamide include N,N-dimethyl (meth)acrylamide, N,N-diethyl (meth)acrylamide, and N,N-dipropyl (meth)acrylamide.

[0046] The mole % content (N-substituted mono(meth)acrylamide unit / water-soluble polymer) includes, for example, 80 mol%, 75 mol%, 70 mol%, 65 mol%, 60 mol%, 55 mol%, 50 mol%, 45 mol%, 40 mol%, 35 mol%, 30 mol%, 25 mol%, 20 mol%, 19 mol%, 17 mol%, 15 mol%, 13 mol%, 11 mol%, 10 mol%, 9 mol%, 7 mol%, 5 mol%, 4 mol%, 2 mol%, 1 mol% and so on. %, 0.9 mol%, 0.7 mol%, 0.5 mol%, 0.45 mol%, 0.4 mol%, 0.35 mol%, 0.3 mol%, 0.25 mol%, 0.20 mol%, 0.15 mol%, 0.10 mol%, 0.08 mol%, 0.06 mol%, 0.05 mol%, 0.03 mol%, 0.01 mol%, 0.009 mol%, 0.007 mol%, 0.005 mol%, 0.003 mol%, 0.001 mol%, 0 mol%, etc. In one embodiment, the content is preferably 0 mol% to 80 mol%, more preferably 1 mol% to 60 mol%, further preferably 0.001 mol% or more and less than 5 mol%, particularly preferably 0.001 mol% to 1 mol%.

[0047] The mass% content (N-substituted mono(meth)acrylamide unit / water-soluble polymer) includes, for example, 80 mass%, 75 mass%, 70 mass%, 65 mass%, 60 mass%, 55 mass%, 50 mass%, 45 mass%, 40 mass%, 35 mass%, 30 mass%, 25 mass%, 20 mass%, 19 mass%, 17 mass%, 15 mass%, 13 mass%, 11 mass%, 10 mass%, 9 mass%, 7 mass%, 5 mass%, 4 mass%, 2 mass%, 1 mass%, 2 mass%, 3 mass%, 4 mass%, 1 mass%, 2 mass%, 3 mass%, 4 mass%, 5 mass%, 5 mass%, 6 mass%, 7 mass%, 5 mass%, 6 mass%, 7 mass%, 5 mass%, 6 mass%, 6 mass%, 7 ... %, 0.9 mass %, 0.7 mass %, 0.5 mass %, 0.45 mass %, 0.4 mass %, 0.35 mass %, 0.3 mass %, 0.25 mass %, 0.20 mass %, 0.15 mass %, 0.10 mass %, 0.08 mass %, 0.06 mass %, 0.05 mass %, 0.03 mass %, 0.01 mass %, 0.009 mass %, 0.007 mass %, 0.005 mass %, 0.003 mass %, 0.001 mass %, 0 mass %, etc. In one embodiment, the content is preferably 0 mass % to 80 mass %, more preferably 1 mass % to 60 mass %, further preferably 0.001 mass % or more and less than 5 mass %, particularly preferably 0.001 mass % to 1 mass %.

[0048] The mole % content (N-monosubstituted mono(meth)acrylamide unit / water-soluble polymer) includes, for example, 0 mol%, 75 mol%, 70 mol%, 65 mol%, 60 mol%, 55 mol%, 50 mol%, 45 mol%, 40 mol%, 35 mol%, 30 mol%, 25 mol%, 20 mol%, 19 mol%, 17 mol%, 15 mol%, 13 mol%, 11 mol%, 10 mol%, 9 mol%, 7 mol%, 5 mol%, 4 mol%, 2 mol%, 1 mol% and 1 mol%. %, 0.9 mol%, 0.7 mol%, 0.5 mol%, 0.45 mol%, 0.4 mol%, 0.35 mol%, 0.3 mol%, 0.25 mol%, 0.20 mol%, 0.15 mol%, 0.10 mol%, 0.08 mol%, 0.06 mol%, 0.05 mol%, 0.03 mol%, 0.01 mol%, 0.009 mol%, 0.007 mol%, 0.005 mol%, 0.003 mol%, 0.001 mol%, 0 mol%, etc. In one embodiment, the content is preferably 0 mol% to 80 mol%, more preferably 0 mol% to 20 mol%, further preferably 0.001 mol% or more and less than 5 mol%, particularly preferably 0.001 mol% to 1 mol%.

[0049] The mass% content (N-monosubstituted mono(meth)acrylamide unit / water-soluble polymer) includes, for example, 80 mass%, 75 mass%, 70 mass%, 65 mass%, 60 mass%, 55 mass%, 50 mass%, 45 mass%, 40 mass%, 35 mass%, 30 mass%, 25 mass%, 20 mass%, 19 mass%, 17 mass%, 15 mass%, 13 mass%, 11 mass%, 10 mass%, 9 mass%, 7 mass%, 5 mass%, 4 mass%, 2 mass%, 1 mass%, 2 mass%, 3 mass%, 4 mass%, 1 mass%, 2 mass%, 3 mass%, 4 mass%, 5 mass%, 5 mass%, 6 mass%, 7 mass%, 5 mass%, 6 mass%, 7 mass%, 5 mass%, 6 mass%, 6 mass%, 7 ... %, 0.9 mass %, 0.7 mass %, 0.5 mass %, 0.45 mass %, 0.4 mass %, 0.35 mass %, 0.3 mass %, 0.25 mass %, 0.20 mass %, 0.15 mass %, 0.10 mass %, 0.08 mass %, 0.06 mass %, 0.05 mass %, 0.03 mass %, 0.01 mass %, 0.009 mass %, 0.007 mass %, 0.005 mass %, 0.003 mass %, 0.001 mass %, 0 mass %, etc. In one embodiment, the content is preferably 0 mass % to 80 mass %, more preferably 0 mass % to 20 mass %, further preferably 0.001 mass % or more and less than 5 mass %, particularly preferably 0.001 mass % to 1 mass %.

[0050] The mole % content (N-disubstituted mono(meth)acrylamide unit / water-soluble polymer) includes, for example, 0 mol%, 75 mol%, 70 mol%, 65 mol%, 60 mol%, 55 mol%, 50 mol%, 45 mol%, 40 mol%, 35 mol%, 30 mol%, 25 mol%, 20 mol%, 19 mol%, 17 mol%, 15 mol%, 13 mol%, 11 mol%, 10 mol%, 9 mol%, 7 mol%, 5 mol%, 4 mol%, 2 mol%, 1 mol% and 1 mol%. %, 0.9 mol%, 0.7 mol%, 0.5 mol%, 0.45 mol%, 0.4 mol%, 0.35 mol%, 0.3 mol%, 0.25 mol%, 0.20 mol%, 0.15 mol%, 0.10 mol%, 0.08 mol%, 0.06 mol%, 0.05 mol%, 0.03 mol%, 0.01 mol%, 0.009 mol%, 0.007 mol%, 0.005 mol%, 0.003 mol%, 0.001 mol%, 0 mol%, etc. In one embodiment, the content is preferably 0 mol% to 80 mol%, more preferably 0 mol% to 20 mol%, further preferably 0.001 mol% or more and less than 5 mol%, particularly preferably 0.001 mol% to 1 mol%.

[0051] The mass% content (N-disubstituted mono(meth)acrylamide unit / water-soluble polymer) includes, for example, 80 mass%, 75 mass%, 70 mass%, 65 mass%, 60 mass%, 55 mass%, 50 mass%, 45 mass%, 40 mass%, 35 mass%, 30 mass%, 25 mass%, 20 mass%, 19 mass%, 17 mass%, 15 mass%, 13 mass%, 11 mass%, 10 mass%, 9 mass%, 7 mass%, 5 mass%, 4 mass%, 2 mass%, 1 mass%, 2 mass%, 3 mass%, 4 mass%, 1 mass%, 2 mass%, 3 mass%, 4 mass%, 5 mass%, 5 mass%, 6 mass%, 7 mass%, 5 mass%, 6 mass%, 7 mass%, 5 mass%, 6 mass%, 6 mass%, 7 ... %, 0.9 mass %, 0.7 mass %, 0.5 mass %, 0.45 mass %, 0.4 mass %, 0.35 mass %, 0.3 mass %, 0.25 mass %, 0.20 mass %, 0.15 mass %, 0.10 mass %, 0.08 mass %, 0.06 mass %, 0.05 mass %, 0.03 mass %, 0.01 mass %, 0.009 mass %, 0.007 mass %, 0.005 mass %, 0.003 mass %, 0.001 mass %, 0 mass %, etc. In one embodiment, the content is preferably 0 mass % to 80 mass %, more preferably 0 mass % to 20 mass %, further preferably 0.001 mass % or more and less than 5 mass %, particularly preferably 0.001 mass % to 1 mass %.

[0052] (Unsaturated hydrocarbon sulfonic acid and / or its salt) In one embodiment, the water-soluble polymer may optionally contain an unsaturated hydrocarbon sulfonic acid and / or a salt thereof unit. The unsaturated hydrocarbon sulfonic acid and / or a salt thereof may be used alone or in combination of two or more.

[0053] The "unsaturated hydrocarbon sulfonic acid" refers to a sulfonic acid whose structure other than the sulfonic acid (salt) group is composed only of carbon atoms and hydrogen atoms.

[0054] Examples of the unsaturated hydrocarbon sulfonic acid or its salt include vinyl sulfonic acid, styrene sulfonic acid, (meth)allyl sulfonic acid, sodium vinyl sulfonate, sodium styrene sulfonate, sodium (meth)allyl sulfonate, and the like.

[0055] The mol% content (unsaturated hydrocarbon sulfonic acid and / or its salt unit / water-soluble polymer) is, for example, 1.0 mol%, 0.95 mol%, 0.9 mol%, 0.85 mol%, 0.8 mol%, 0.75 mol%, 0.7 mol%, 0.65 mol%, 0.6 mol%, 0.55 mol%, 0.5 mol%, 0.45 mol%, 0.4 mol%, 0.35 mol%, 0.3 mol%, 0.25 mol%, 0.20 mol%, 0.15 mol%, 0.10 mol%, 0.08 mol%, 0.06 mol%, 0.05 mol%, 0.03 mol%, 0.01 mol%, 0.009 mol%, 0.007 mol%, 0.005 mol%, 0.003 mol%, 0.001 mol%, 0 mol%, etc. In one embodiment, the content is preferably 0 mol% to 1.0 mol%, more preferably 0.001 mol% to 0.5 mol%, further preferably 0.001 mol% to 0.1 mol%, and particularly preferably less than 0.01 mol%. The reasons for this preference include, for example, improved pencil hardness and improved breaking strength.

[0056] Examples of the mass % content (unsaturated hydrocarbon sulfonic acid and / or salt thereof unit / water-soluble polymer) include 1.0 mass %, 0.95 mass %, 0.9 mass %, 0.85 mass %, 0.8 mass %, 0.75 mass %, 0.7 mass %, 0.65 mass %, 0.6 mass %, 0.55 mass %, 0.5 mass %, 0.45 mass %, 0.4 mass %, 0.35 mass %, 0.3 mass %, 0.25 mass %, 0.20 mass %, 0.15 mass %, 0.10 mass %, 0.08 mass %, 0.06 mass %, 0.05 mass %, 0.03 mass %, 0.01 mass %, 0.009 mass %, 0.007 mass %, 0.005 mass %, 0.003 mass %, 0.001 mass %, and 0 mass %. In one embodiment, the content is preferably 0% by mass to 1.0% by mass, more preferably 0.001% by mass to 0.5% by mass, and further preferably 0.001% by mass to 0.1% by mass. The reasons for this preference include, for example, improved pencil hardness and improved breaking strength.

[0057] The neutralization rate [unsaturated hydrocarbon sulfonate unit mass / (unsaturated hydrocarbon sulfonate unit mass+unsaturated hydrocarbon sulfonic acid unit mass)] includes, for example, 100%, 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, etc. In one embodiment, the neutralization rate is preferably 10% to 100%.

[0058] (Multifunctional monomer) In one embodiment, the water-soluble polymer may optionally include a multifunctional monomer unit. The multifunctional monomer may be used alone or in combination of two or more.

[0059] The "polyfunctional monomer" refers to a monomer having two or more ethylenically unsaturated double bonds.

[0060] Examples of the polyfunctional monomer include polyfunctional (meth)acrylamide compounds, tri(allyl)-containing monomers, and triazine containing tri((meth)acryloyl) groups.

[0061] The "polyfunctional (meth)acrylamide compound" refers to a compound having two or more (meth)acrylamide groups. [Chemistry 1] (Where R 1 is a hydrogen atom or a methyl group. )

[0062] Examples of the polyfunctional (meth)acrylamide compound include N,N'-methylenebis(meth)acrylamide, N,N'-ethylenebis(meth)acrylamide, N-[tris(3-(meth)acrylamidepropoxymethyl)methyl](meth)acrylamide, N,N-bis(2-(meth)acrylamideethyl)(meth)acrylamide, N,N-[oxybis(2,1-ethylenedioxy-3,1-propylenediyl)]bis(meth)acrylamide, and N,N-1,2-ethylenediylbis{N-[2-((meth)acrylamide)ethyl](meth)acrylamide}.

[0063] Examples of the tri(allyl) group-containing monomer include triallyl isocyanurate, triallyl trimellitate, triallylamine, and triallyl(meth)acrylamide.

[0064] Examples of the triazine containing a tri((meth)acryloyl group) include 1,3,5-tri((meth)acryloyl)-1,3,5-triazine and 1,3,5-tri((meth)acryloyl)hexahydro-1,3,5-triazine.

[0065] The mole % content (multifunctional monomer unit / water-soluble polymer) includes, for example, 10 mol%, 9 mol%, 8 mol%, 7 mol%, 6 mol%, 5 mol%, 4 mol%, 3 mol%, 2 mol%, 1 mol%, 0.9 mol%, 0.7 mol%, 0.5 mol%, 0.3 mol%, 0.1 mol%, 0.05 mol%, 0 mol%, etc. In one embodiment, the content is preferably 0 mass % to 10 mol%, more preferably 0.05 mol% to 2 mol%.

[0066] Examples of the mass % content (polyfunctional monomer unit / water-soluble polymer) include 10 mass %, 9 mass %, 8 mass %, 7 mass %, 6 mass %, 5 mass %, 4 mass %, 3 mass %, 2 mass %, 1 mass %, 0.9 mass %, 0.7 mass %, 0.5 mass %, 0.3 mass %, 0.1 mass %, 0.05 mass %, and 0 mass %. In one embodiment, the content is preferably 0% by mass to 10% by mass, and more preferably 0.05% by mass to 2% by mass.

[0067] (unsaturated carboxylic acid and / or its salt) In one embodiment, the water-soluble polymer may optionally contain an unsaturated carboxylic acid and / or a salt thereof unit. The unsaturated carboxylic acid and / or a salt thereof may be used alone or in combination of two or more.

[0068] Examples of the unsaturated carboxylic acid or its salt include (meth)acrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, sodium (meth)acrylate, sodium crotonate, sodium maleate, sodium fumarate, sodium itaconate, lithium (meth)acrylate, lithium crotonate, lithium maleate, lithium fumarate, lithium itaconate, calcium (meth)acrylate, calcium crotonate, calcium maleate, calcium fumarate, calcium itaconate, ammonium (meth)acrylate, ammonium crotonate, ammonium maleate, ammonium fumarate, and ammonium itaconate.

[0069] The mole % content (unsaturated carboxylic acid and / or its salt unit / water-soluble polymer) includes, for example, 70 mol%, 65 mol%, 60 mol%, 55 mol%, 50 mol%, 45 mol%, 40 mol%, 35 mol%, 30 mol%, 25 mol%, 20 mol%, 15 mol%, 10 mol%, 5 mol%, 4 mol%, 2 mol%, 1 mol%, 0 mol%, etc. In one embodiment, the content is preferably 0 mol% to 70 mol%, more preferably 2 mol% to 40 mol%.

[0070] The mass % content (unsaturated carboxylic acid and / or its salt unit / water-soluble polymer) includes, for example, 70 mass %, 65 mass %, 60 mass %, 55 mass %, 50 mass %, 45 mass %, 40 mass %, 35 mass %, 30 mass %, 29 mass %, 25 mass %, 20 mass %, 15 mass %, 10 mass %, 9 mass %, 5 mass %, 4 mass %, 2 mass %, 1 mass %, 0 mass %, etc. In one embodiment, the content preferably includes 0 mass % to 70 mass %, more preferably 0 mass % to 40 mass %, and further preferably 2 mass % to 40 mass %.

[0071] Neutralization rate [unsaturated carboxylate unit mass / (unsaturated carboxylate unit mass+unsaturated carboxylic acid unit mass)] includes, for example, 100%, 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, etc. In one embodiment, the neutralization rate is preferably 10% to 100%.

[0072] (α,β-unsaturated nitrile) In one embodiment, the water-soluble polymer may optionally contain an α,β-unsaturated nitrile unit. The α,β-unsaturated nitrile may be used alone or in combination of two or more.

[0073] Examples of the α,β-unsaturated nitrile include (meth)acrylonitrile, α-chloro(meth)acrylonitrile, α-ethyl(meth)acrylonitrile, and vinylidene cyanide.

[0074] The mole % content (α, β-unsaturated nitrile unit / water-soluble polymer) includes, for example, 50 mol%, 45 mol%, 40 mol%, 35 mol%, 30 mol%, 25 mol%, 20 mol%, 15 mol%, 10 mol%, 9 mol%, 5 mol%, 4 mol%, 2 mol%, 1 mol%, 0 mol%, etc. In one embodiment, the content is preferably 0 mol% to 50 mol%, more preferably 0 mol% to 40 mol%, and further preferably 10 mol% to 40 mol%.

[0075] The mass % content (α, β-unsaturated nitrile unit / water-soluble polymer) includes, for example, 50 mass %, 45 mass %, 40 mass %, 35 mass %, 30 mass %, 25 mass %, 20 mass %, 15 mass %, 10 mass %, 9 mass %, 5 mass %, 4 mass %, 2 mass %, 1 mass %, 0 mass %, etc. In one embodiment, the content is preferably 0 mass % to 50 mass %, more preferably 0 mass % to 30 mass %, and further preferably 5 mass % to 30 mass %.

[0076] (Alkoxyalkyl (meth)acrylate unit) In one embodiment, the water-soluble polymer may optionally include an alkoxyalkyl(meth)acrylate unit. The alkoxyalkyl(meth)acrylate may be used alone or in combination of two or more.

[0077] Examples of the alkoxyalkyl (meth)acrylate include methoxymethyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 1-methoxyethyl (meth)acrylate, 3-methoxypropyl (meth)acrylate, 2-methoxypropyl (meth)acrylate, 1-methoxypropyl (meth)acrylate, 4-methoxybutyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, 2-methoxybutyl (meth)acrylate, 1-methoxybutyl (meth)acrylate, ethoxymethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 1-ethoxyethyl (meth)acrylate, 3-ethoxypropyl (meth)acrylate, 2-ethoxypropyl (meth)acrylate, 1-ethoxypropyl (meth)acrylate, propoxymethyl (meth)acrylate, 2-propoxyethyl (meth)acrylate, 1-propoxyethyl (meth)acrylate, and butoxymethyl (meth)acrylate.

[0078] Examples of the mole % content (alkoxyalkyl (meth)acrylate unit / water-soluble polymer) include 40 mol %, 35 mol %, 30 mol %, 25 mol %, 20 mol %, 15 mol %, 10 mol %, 9 mol %, 5 mol %, 4 mol %, 2 mol %, 1 mol %, 0 mol %, etc. In one embodiment, the content is preferably 0 mol % to 40 mol %.

[0079] The mass % content ((meth) alkoxyalkyl acrylate unit / water-soluble polymer) includes, for example, 60 mass %, 55 mass %, 50 mass %, 45 mass %, 40 mass %, 35 mass %, 30 mass %, 25 mass %, 20 mass %, 15 mass %, 10 mass %, 9 mass %, 5 mass %, 4 mass %, 2 mass %, 1 mass %, 0 mass %, etc. In one embodiment, the content is preferably 0 mass % to 60 mass %.

[0080] (Hydroxy-containing monomers) In one embodiment, the water-soluble polymer may optionally contain a hydroxyl group-containing monomer unit. The hydroxyl group-containing monomer may be used alone or in combination of two or more.

[0081] Examples of the hydroxyl group-containing monomer include hydroxyl group-containing (meth)acrylates and hydroxyl group-containing vinyl ethers.

[0082] Examples of the hydroxyl group-containing (meth)acrylate include hydroxyl group-containing linear (meth)acrylate and hydroxyl group-containing branched (meth)acrylate.

[0083] Examples of the hydroxyl group-containing linear (meth)acrylate include 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate.

[0084] Examples of the hydroxyl-containing branched (meth)acrylate include 1-hydroxyethyl (meth)acrylate, 1-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxy-1-methylethyl (meth)acrylate, 1-hydroxy-2-methylethyl (meth)acrylate, 1-hydroxybutyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 1-hydroxy-1-methyl-propyl (meth)acrylate, 2-hydroxy-1-methyl-propyl (meth)acrylate, 3-hydroxy-1-methyl-propyl (meth)acrylate, 1-ethyl-2-hydroxyethyl (meth)acrylate, 1-hydroxy-2-methyl-propyl (meth)acrylate, 2-hydroxy-2-methyl-propyl (meth)acrylate, 3-hydroxy-2-methyl-propyl (meth)acrylate, and 1,1-dimethyl-2-hydroxyethyl (meth)acrylate.

[0085] Examples of the hydroxyl group-containing vinyl ether include hydroxyalkyl vinyl ether and polyalkylene glycol monovinyl ether.

[0086] Examples of the hydroxyalkyl vinyl ether include hydroxy linear alkyl vinyl ether, hydroxy branched alkyl vinyl ether, and hydroxy cycloalkyl vinyl ether.

[0087] Examples of the hydroxy linear alkyl vinyl ether include 2-hydroxyethyl vinyl ether, 3-hydroxypropyl vinyl ether, 4-hydroxybutyl vinyl ether, and 5-hydroxypentyl vinyl ether.

[0088] Examples of the hydroxy-branched alkyl vinyl ether include 2-hydroxypropyl vinyl ether, 2-hydroxy-2-methylpropyl vinyl ether, and 4-hydroxy-2-methylbutyl vinyl ether.

[0089] Examples of the hydroxycycloalkyl vinyl ether include 4-hydroxycyclopentyl vinyl ether.

[0090] Examples of the polyalkylene glycol monovinyl ether include polymethylene glycol monovinyl ether, polyethylene glycol monovinyl ether, and polypropylene glycol monovinyl ether.

[0091] Examples of the polymethylene glycol monovinyl ether include dimethylene glycol monovinyl ether, trimethylene glycol monovinyl ether, tetramethylene glycol monovinyl ether, pentamethylene glycol monovinyl ether, hexamethylene glycol monovinyl ether, heptamethylene glycol monovinyl ether, octamethylene glycol monovinyl ether, nonamethylene glycol monovinyl ether and decamethylene glycol monovinyl ether.

[0092] Examples of polyethylene glycol monovinyl ether include diethylene glycol monovinyl ether, triethylene glycol monovinyl ether, tetraethylene glycol monovinyl ether, pentaethylene glycol monovinyl ether, hexaethylene glycol monovinyl ether, heptaethylene glycol monovinyl ether, octaethylene glycol monovinyl ether, nonaethylene glycol monovinyl ether and decaethylene glycol monovinyl ether.

[0093] Examples of the polypropylene glycol monovinyl ether include dipropylene glycol monovinyl ether, tripropylene glycol monovinyl ether, tetrapropylene glycol monovinyl ether, pentapropylene glycol monovinyl ether, hexapropylene glycol monovinyl ether, heptapropylene glycol monovinyl ether, octapropylene glycol monovinyl ether, nonapropylene glycol monovinyl ether and decapropylene glycol monovinyl ether.

[0094] The mole % content (hydroxyl-containing monomer unit / water-soluble polymer) includes, for example, 80 mol%, 75 mol%, 70 mol%, 65 mol%, 60 mol%, 55 mol%, 50 mol%, 45 mol%, 40 mol%, 35 mol%, 30 mol%, 25 mol%, 20 mol%, 15 mol%, 10 mol%, 9 mol%, 5 mol%, 4 mol%, 2 mol%, 1 mol%, 0 mol%, etc. In one embodiment, the content preferably includes 0 mol% to 80 mol%, more preferably 5 mol% to 50 mol%, and further preferably 20 mol% to 40 mol%.

[0095] The mass % content (hydroxyl-containing monomer unit / water-soluble polymer) includes, for example, 85 mass %, 80 mass %, 75 mass %, 70 mass %, 65 mass %, 60 mass %, 55 mass %, 50 mass %, 45 mass %, 40 mass %, 35 mass %, 30 mass %, 25 mass %, 20 mass %, 15 mass %, 10 mass %, 9 mass %, 5 mass %, 4 mass %, 2 mass %, 1 mass %, 0 mass %, etc. In one embodiment, the content preferably includes 0 mass % to 85 mass %, more preferably 10 mass % to 70 mass %, and further preferably 25 mass % to 45 mass %.

[0096] (Polymerization initiator) The polymerization initiator may be used alone or in combination of two or more.

[0097] Examples of the polymerization initiator include azo initiators.

[0098] Examples of the azo initiator include 2,2′-azobis(2-amidinopropane) dihydrochloride and the like.

[0099] The mole % content (polymerization initiator unit / water-soluble polymer) includes, for example, 1 mol%, 0.95 mol%, 0.9 mol%, 0.85 mol%, 0.8 mol%, 0.75 mol%, 0.7 mol%, 0.65 mol%, 0.6 mol%, 0.55 mol%, 0.5 mol%, 0.45 mol%, 0.4 mol%, 0.35 mol%, 0.3 mol%, 0.25 mol%, 0.2 mol%, 0.15 mol%, 0.1 mol%, 0.07 mol%, 0.05 mol%, 0.03 mol%, 0.01 mol%, etc. In one embodiment, the content is preferably 0.01 mol% to 1 mol%.

[0100] The mass % content (polymerization initiator unit / water-soluble polymer) includes, for example, 1 mass %, 0.95 mass %, 0.9 mass %, 0.85 mass %, 0.8 mass %, 0.75 mass %, 0.7 mass %, 0.65 mass %, 0.6 mass %, 0.55 mass %, 0.5 mass %, 0.45 mass %, 0.4 mass %, 0.35 mass %, 0.3 mass %, 0.25 mass %, 0.2 mass %, 0.15 mass %, 0.1 mass %, 0.07 mass %, 0.05 mass %, 0.03 mass %, 0.01 mass %, etc. In one embodiment, the content is preferably 0.01 mass % to 1 mass %.

[0101] (Monomers other than any of the above: other components) The water-soluble polymer may optionally contain monomer (other component) units that are not any of (meth)acrylamide, N-substituted mono(meth)acrylamide, unsaturated hydrocarbon sulfonic acid and / or its salt, multifunctional monomer, unsaturated carboxylic acid and / or its salt, α,β-unsaturated nitrile, (meth)acrylic acid alkoxyalkyl ester, and hydroxyl-containing monomer. Other components may be used alone or in combination of two or more.

[0102] Examples of other components include unsaturated phosphoric acid and / or its salt, alkyl (meth)acrylate, conjugated diene, aromatic vinyl compound, and the like.

[0103] Examples of the unsaturated phosphoric acid include vinylphosphonic acid, vinyl phosphate, bis((meth)acryloyloxyethyl)phosphate, diphenyl-2-(meth)acryloyloxyethyl phosphate, dibutyl-2-(meth)acryloyloxyethyl phosphate, dioctyl-2-(meth)acryloyloxyethyl phosphate, monomethyl-2-(meth)acryloyloxyethyl phosphate, and 3-(meth)acryloyloxy-2-hydroxypropane phosphate.

[0104] Examples of the alkyl (meth)acrylate include linear alkyl (meth)acrylate, branched alkyl (meth)acrylate, and alicyclic alkyl (meth)acrylate.

[0105] Examples of the linear alkyl (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, n-pentyl (meth)acrylate, hexyl (meth)acrylate, n-octyl (meth)acrylate, nonyl (meth)acrylate, and decyl (meth)acrylate.

[0106] Examples of the branched alkyl (meth)acrylate include isopropyl (meth)acrylate, isobutyl (meth)acrylate, isoamyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate.

[0107] Examples of the alicyclic alkyl (meth)acrylate include cyclohexyl (meth)acrylate and the like.

[0108] Examples of the conjugated diene include 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 2-chloro-1,3-butadiene, substituted straight-chain conjugated pentadiene, and substituted conjugated hexadiene having a side chain.

[0109] Examples of the aromatic vinyl compound include styrene, α-methylstyrene, p-methylstyrene, vinyltoluene, chlorostyrene, and divinylbenzene.

[0110] The mass % content (other component units / water-soluble polymer) includes, for example, less than 10 mass %, less than 9 mass %, less than 7 mass %, less than 5 mass %, less than 4 mass %, less than 2 mass %, less than 1 mass %, less than 0.9 mass %, less than 0.7 mass %, less than 0.5 mass %, less than 0.4 mass %, less than 0.2 mass %, less than 0.1 mass %, 0 mass %, etc. In one embodiment, the content is preferably less than 10 mass %, more preferably less than 5 mass %, further preferably less than 1 mass %, and particularly preferably 0 mass %.

[0111] The mole % content (other component units / water-soluble polymer) is, for example, less than 10 mol %, less than 9 mol %, less than 7 mol %, less than 5 mol %, less than 4 mol %, less than 3 mol %, less than 2 mol %, less than 1 mol %, or 0 mol %. In one embodiment, the content is preferably less than 10 mol %, more preferably less than 5 mol %, further preferably less than 1 mol %, and particularly preferably 0 mol %.

[0112] <Production method (water-soluble polymer)> In one embodiment, the production method (water-soluble polymer) includes a pre-polymerization step and a post-polymerization step.

[0113] (Pre-polymerization process) The "prepolymerization step" refers to a step of producing (polymerizing) a water-soluble polymer.

[0114] The mass % usage amount (radical polymerization initiator / monomer group) in the pre-polymerization step is, for example, 1.0 mass %, 0.9 mass %, 0.8 mass %, 0.7 mass %, 0.6 mass %, 0.5 mass %, 0.4 mass %, 0.3 mass %, 0.2 mass %, 0.1 mass %, 0.05 mass %, etc. In one embodiment, the usage amount in the pre-polymerization step is preferably 0.05 mass % to 1.0 mass %.

[0115] Examples of the prepolymerization temperature include 100° C., 95° C., 90° C., 85° C., 80° C., 75° C., 70° C., 65° C., 60° C., 55° C., and 50° C. In one embodiment, the prepolymerization temperature is preferably 50° C. to 100° C.

[0116] Examples of the prepolymerization time include 10 hours, 9 hours, 8 hours, 7 hours, 6 hours, 5 hours, 4 hours, 3 hours, 2 hours, 1.5 hours, and 1 hour. In one embodiment, the prepolymerization time is preferably 1 to 10 hours, more preferably 2 to 10 hours.

[0117] (Post-polymerization process) The "post-polymerization step" refers to a step of further adding a polymerization initiator to allow the reaction to proceed after the pre-polymerization step.

[0118] The post-polymerization step may be performed once or twice or more.

[0119] The mass % usage (radical polymerization initiator / monomer group) in the post-polymerization step is, for example, 1.0 mass %, 0.9 mass %, 0.8 mass %, 0.7 mass %, 0.6 mass %, 0.5 mass %, 0.4 mass %, 0.3 mass %, 0.2 mass %, 0.1 mass %, 0.05 mass %, etc. In one embodiment, the usage is preferably 0.05 mass % to 1.0 mass %.

[0120] Examples of the post-polymerization temperature include 100° C., 95° C., 90° C., 85° C., 80° C., 75° C., 70° C., 65° C., 60° C., 55° C., and 50° C. In one embodiment, the post-polymerization temperature is preferably 50° C. to 100° C.

[0121] Examples of the post-polymerization time include 10 hours, 9 hours, 8 hours, 7 hours, 6 hours, 5 hours, 4 hours, 3 hours, 2 hours, 1.5 hours, and 1 hour. In one embodiment, the post-polymerization time is preferably 1 to 10 hours, more preferably 2 to 10 hours.

[0122] In one embodiment, in either the post-polymerization step or the pre-polymerization step, a persulfate or a redox polymerization initiator may be used as a radical polymerization initiator.

[0123] Examples of the persulfate include potassium persulfate and ammonium persulfate.

[0124] Examples of the redox polymerization initiator include a combination system (persulfate and reducing agent) and the like.

[0125] Examples of the reducing agent include sodium bisulfite and the like.

[0126] <Physical properties (water-soluble polymers), etc.> The weight average molecular weight (water-soluble polymer: Mw) includes, for example, 6 million, 5.5 million, 5 million, 4.5 million, 4 million, 3.5 million, 3 million, 2.5 million, 2 million, 1.5 million, 1 million, 950,000, 900,000, 850,000, 800,000, 750,000, 700,000, 650,000, 600,000, 550,000, 500,000, 450,000, 400,000, 350,000, 300,000, 250,000, 200,000, 150,000, 100,000, etc. In one embodiment, the weight average molecular weight (Mw) is preferably 100,000 to 6 million, and more preferably 350,000 to 6 million.

[0127] The number average molecular weight (water-soluble polymer: Mn) includes, for example, 6 million, 5.5 million, 5 million, 4.5 million, 4 million, 3.5 million, 3 million, 2.5 million, 2 million, 1.5 million, 1 million, 950,000, 900,000, 850,000, 800,000, 750,000, 700,000, 650,000, 600,000, 550,000, 500,000, 450,000, 400,000, 300,000, 200,000, 100,000, 50,000, 10,000, etc. In one embodiment, the number average molecular weight (Mn) is preferably 10,000 or more.

[0128] Examples of the molecular weight distribution (water-soluble polymer: Mw / Mn) include 15, 14, 13, 11, 10, 9, 7.5, 5, 4, 3, 2.9, 2.5, 2, 1.5, and 1.1. In one embodiment, the molecular weight distribution (Mw / Mn) is preferably 1.1-15.

[0129] The measurement conditions (weight average molecular weight, number average molecular weight) are as follows. ·Measurement instrument: GPC (model: HLC-8420) manufactured by Tosoh Corporation · Column: TSKgel guardcolum PWXL, TSK-GEL G4000, TSK-GELα-M (all manufactured by Tosoh Corporation) · Eluent: 0.2M NaNO3 50mM phosphate buffer / acetonitrile = 90 / 10 (v / v) aqueous solution Column temperature: 40℃ Standard curve: Standard polyethylene oxide-polyethylene glycol ·Measurement concentration: 0.10 mass % (water-soluble polymer concentration) Filter: Cellulose acetate cartridge filter (manufactured by Tosoh Corporation, Microdiesk W-13-2, pore size 0.2 μm)

[0130] The content ((meth)acrylamide / water-soluble polymer) in parts by mass is, for example, less than 1000 ppm by mass, 9 99 mass ppm, 950 mass ppm, 900 mass ppm, 850 mass ppm, 800 mass ppm, 750 mass ppm, 700 mass ppm, 650 mass ppm, 600 mass ppm, 550 mass ppm, 500 mass ppm, 450 mass ppm, 400 mass ppm, 350 mass ppm, 300 mass ppm, 250 mass ppm, 200 mass ppm, 150 mass ppm, 100 mass ppm, 50 mass ppm, 25 mass ppm, 10 mass ppm, 5 mass ppm, 1 mass ppm, 0.9 mass ppm, 0.7 mass ppm, 0.5 mass ppm, 0.3 mass ppm, 0.1 mass ppm, 0.09 mass ppm, 0.07 mass ppm, 0.05 mass ppm, 0.03 mass ppm, 0.01 mass ppm, etc. In one embodiment, the content is preferably 0.01 mass ppm or more and less than 1000 mass ppm.

[0131] Examples of the content ((meth)acrylonitrile / water-soluble polymer) include less than 1000 mass ppm, 999 mass ppm, 950 mass ppm, 900 mass ppm, 850 mass ppm, 800 mass ppm, 750 mass ppm, 700 mass ppm, 650 mass ppm, 600 mass ppm, 550 mass ppm, 500 mass ppm, 450 mass ppm, 400 mass ppm, 350 mass ppm, 300 mass ppm, 250 mass ppm, 200 mass ppm, 150 mass ppm, 100 mass ppm, 50 mass ppm, 25 mass ppm, 10 mass ppm, 5 mass ppm, 1 mass ppm, 0.9 mass ppm, 0.7 mass ppm, 0.5 mass ppm, 0.3 mass ppm, 0.1 mass ppm, 0.09 mass ppm, 0.07 mass ppm, 0.05 mass ppm, 0.03 mass ppm, 0.01 mass ppm, and 0 mass ppm. In one embodiment, the content is preferably 0 mass ppm or more and less than 1000 mass ppm.

[0132] The content (monomer / water-soluble polymer) by mass is, for example, less than 2000 mass ppm, 1999 mass ppm, 1950 mass ppm, 1900 mass ppm, 1850 mass ppm, 1800 mass ppm, 1750 mass ppm, 1700 mass ppm, 1650 mass ppm, 1600 mass ppm, 1550 mass ppm, 1500 mass ppm, 1450 mass ppm, 1400 mass ppm, 1350 mass ppm, 1300 mass ppm, 1250 mass ppm, 1200 mass ppm, 1150 mass ppm, 1100 mass ppm, 1050 mass ppm, 1000 mass ppm, ppm, 999 mass ppm, 950 mass ppm, 900 mass ppm, 850 mass ppm, 800 mass ppm, 750 mass ppm, 700 mass ppm, 650 mass ppm, 600 mass ppm, 550 mass ppm, 500 mass ppm, 450 mass ppm, 400 mass ppm, 350 mass ppm, 300 mass ppm, 250 mass ppm, 200 mass ppm, 150 mass ppm, 100 mass ppm, 50 mass ppm, 25 mass ppm, 10 mass ppm, 5 mass ppm, 1 mass ppm, 0.9 mass ppm, 0.7 mass ppm, 0.5 mass ppm, 0.3 mass ppm, 0.1 mass ppm, 0.09 mass ppm, 0.07 mass ppm, 0.05 mass ppm, 0.03 mass ppm, 0.01 mass ppm, etc. In one embodiment, the content is preferably 0.01 mass ppm or more and less than 1000 mass ppm, more preferably 0.01 mass ppm or more and less than 100 mass ppm.

[0133] The monomer content can be measured under the following conditions. (1) Preparation (standard solution) Monomers ((meth)acrylamide, (meth)acrylonitrile) were collected in 20 mL spiral tubes and diluted with ultrapure water to prepare standard aqueous solutions of 2000 ppm, 1000 ppm, 500 ppm, 100 ppm, 10 ppm, 1 ppm, and 0.5 ppm. (2) Calibration curve of (meth)acrylamide The standard solution was used to perform measurement under the following conditions to prepare a calibration curve. Measurement instrument: HPLC (Agilent 1260Infinity2 PrimeLC) Column: InertSustain AQ-C18 Column oven temperature: 40°C Eluent: Phosphate buffer (sodium dihydrogen phosphate / ultrapure water = 8 / 1000 (v / v) aqueous solution) Measurement concentration: 0.20 mass% (water-soluble polymer concentration) Injection volume: 4 μL (3) (Meth)acrylonitrile calibration curve The standard solution was used to perform measurement under the following conditions to prepare a calibration curve. Measuring instrument: GC (Agilent 7890B)-MS (Agilent 5977A) Column: InertCap AQUATIC-2 Carrier gas: Helium Measurement concentration: 1 mass % (water-soluble polymer concentration) Measurement conditions: 50℃(2min.)→230℃(5min. / min.) Injection volume: 1000μL (4) Preparation (sample) Each sample was diluted 50 times in a spiral tube. The measurement was performed under the above conditions, and the monomer content in the sample was calculated based on the calibration curve.

[0134] (Meth)acrylamide can be produced by hydrolyzing (meth)acrylonitrile. Therefore, even when (meth)acrylonitrile is not used as a monomer, (meth)acrylonitrile may be present in the reaction system.

[0135] The mass ppm content (sulfur / storage device binder aqueous solution) includes, for example, 1000ppm, 950ppm, 900ppm, 850ppm, 800ppm, 750ppm, 700ppm, 650ppm, 600ppm, 550ppm, 500ppm, 450ppm, 400ppm, 350ppm, 300ppm, 250ppm, 200ppm, 150ppm, 100ppm, 90ppm, 75ppm, 50ppm, 25ppm, 15ppm, 14ppm, 13ppm, 11ppm, 10ppm, 9ppm, 7ppm, 5ppm, 3ppm, 1ppm, 0ppm, etc. In one embodiment, the content is preferably 1000ppm or less. The preferred reasons include, for example, improved pencil hardness and improved breaking strength.

[0136] The sulfur content can be measured under the following conditions. The measurement was performed using a fluorescent X-ray analyzer (ZSX Primus IV manufactured by Rigaku Corporation). The content was calculated as a value converted into oxides. <Measurement conditions> Measurement atmosphere: Helium Sample form: liquid Measuring range: F~U Measuring diameter: 30mm Measuring time: Standard Pre-treatment: Place in a liquid sample container and cover with polypropylene (PP) film Quantitative method: Semi-quantitative analysis using fundamental parameter method When no content was detected (0 ppm) by a fluorescent X-ray analyzer, the content was measured using combustion ion chromatography (AQF-2100H manufactured by Nitto Seiko Analytical Science Co., Ltd.). <Measurement conditions> Separation column: Product name "IonPac AS12A", manufactured by DIONEX (inner diameter 4 mm, length 200 mm) Guard column: Product name "IonPac AG12A", manufactured by DIONEX (inner diameter 4 mm, length 50 mm) ·Pre-treatment: None Quantitative method: Quantitative analysis using a calibration curve using a standard sample (Na2SO4) Solid weight of burning sample: 50 mg ·Gas absorption liquid volume after combustion: 10mL Internal standard sample (sodium tartrate dihydrate) concentration of absorption liquid: 10ppm (tartrate ion concentration) · Hydrogen peroxide concentration in the absorption liquid (hydrogen peroxide aqueous solution): 90ppm Eluent: 2.7mmol / L sodium carbonate + 0.3mmol / L sodium bicarbonate aqueous solution · The absorption solution is prepared by diluting it in ultrapure water

[0137] Examples of the type B viscosity (electrical storage device binder aqueous solution) include 100,000 mPa·s, 90,000 mPa·s, 80,000 mPa·s, 70,000 mPa·s, 60,000 mPa·s, 50,000 mPa·s, 40,000 mPa·s, 30,000 mPa·s, 20,000 mPa·s, 10,000 mPa·s, 9000 mPa·s, 8000 mPa·s, 7000 mPa·s, 6000 mPa·s, 5000 mPa·s, 4000 mPa·s, 3000 mPa·s, 2000 mPa·s, and 1000 mPa·s. In one embodiment, the type B viscosity is preferably 1000 mPa·s to 1000,000 mPa·s.

[0138] The measurement conditions (B-type viscosity) are as follows. Non-volatile content: 15% by mass Measurement temperature: 25℃ B-type viscometer: manufactured by Toki Sangyo Co., Ltd. (Toki Sangyo Co., Ltd.) Product name: "B-type viscometer model TVB-10" Viscosity 100 to 10,000 mPa·s: No. 3 rotor, speed 12 rpm Viscosity over 10000-20000 mPa·s: No.3 rotor, speed 6 rpm Viscosity over 20000100000 mPa·s: No.4 rotor, speed 6 rpm

[0139] The glass transition temperature (water-soluble polymer) includes, for example, 160°C, 155°C, 150°C, 145°C, 140°C, 135°C, 130°C, 125°C, 120°C, 115°C, 110°C, 105°C, 100°C, 95°C, 90°C, 85°C, 80°C, 75°C, 70°C, 65°C, 60°C, 55°C, 50°C, 45°C, 40°C, 35°C, 30°C, 25°C, 20°C, 15°C, 10°C, 5°C, 0°C, etc. In one embodiment, the glass transition temperature is preferably 0°C or higher, more preferably 30°C or higher.

[0140] Based on the glass transition temperature (homopolymer) and the mass fraction (monomer), the glass transition temperature (water-soluble polymer) can be calculated using the Fox equation. 1 / Tg=(W1 / Tg1)+(W2 / Tg2)+(W3 / Tg3)+···+(W n / Tg n) [Fox formula, Tg represents the glass transition temperature of the polymer to be obtained (K), W1~W n Indicates the mass fraction of each monomer, Tg1~Tg n represents the glass transition temperature of each monomer (homopolymer) (K)]

[0141] The glass transition temperature can be measured by DSC (differential scanning calorimeter), DTA (differential thermal analyzer), TMA (thermomechanical analyzer) or the like. The measurement conditions (glass transition temperature) are as follows. Temperature range: -100℃~300℃ Heating rate: 10℃ / min

[0142] The glass transition temperature (homopolymer) may also be a value described in the literature. Examples of the literature include "Basic Chemical Handy Manual II, edited by the Chemical Society of Japan (revised 5th edition)", p325. Examples of the glass transition temperature (homopolymer) include the following temperatures. Examples of the glass transition temperature (homopolymer) include the following temperatures. Acrylamide: 165℃ Acrylic acid: 106°C Hydroxyethyl acrylate: -15°C Acrylonitrile: 105℃

[0143] Examples of the mass % content (water-soluble polymer / electrical storage device binder aqueous solution) include 25 mass %, 20 mass %, 19 mass %, 15 mass %, 14 mass %, 12 mass %, 10 mass %, 9 mass %, 7 mass %, 6 mass %, 5 mass %, 4 mass %, 3 mass %, 2 mass %, 1 mass %, etc. In one embodiment, the content is preferably 1 mass % to 25 mass %.

[0144] <Water> Examples of water include ultrapure water, pure water, distilled water, ion-exchanged water, and tap water.

[0145] Examples of the mass % content (water / electrical storage device binder aqueous solution) include 99.9 mass %, 99 mass %, 95 mass %, 90 mass %, 85 mass %, 80 mass %, 75 mass %, etc. In one embodiment, the content is preferably 75 mass % to 99.9 mass %.

[0146] Examples of the mass ratio (water-soluble polymer / water) include 0.33, 0.30, 0.25, 0.24, 0.22, 0.20, 0.18, 0.15, 0.12, 0.10, 0.09, 0.07, and 0.05. In one embodiment, the mass ratio is preferably 0.05 to 0.33.

[0147] <Hydrolysis partial condensate of polyalkoxysilane: Hydrolysis partial condensate> In one embodiment, the aqueous solution of the electrical storage device binder may optionally contain a hydrolyzed partial condensate of polyalkoxysilane. The hydrolyzed partial condensate may be used alone or in combination of two or more.

[0148] Examples of the polyalkoxysilane include trialkoxysilane and tetraalkoxysilane.

[0149] In one embodiment, the trialkoxysilane is represented by the following formula.

Chemical Si1

[0150] The "substituted alkyl group" means a group in which a hydrogen atom constituting an alkyl group is substituted with a group other than a hydrogen atom and an alkyl group.

[0151] Examples of the substituent include an amino group, a mercapto group, an isocyanate group, and a (meth)acryloyloxy group.

[0152] The amino group (amino group-containing group) is represented by the following formula. -NR am1 R am2 (R am1 ~R am2 Each independently represents a hydrogen atom, an alkyl group or an aryl group. )

[0153] Examples of the amino group-containing trialkoxysilane include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-2(aminoethyl)3-aminopropyltrimethoxysilane, N-2(aminoethyl)3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylene)propylamine, and N-phenyl-3-aminopropyltrimethoxysilane.

[0154] Examples of the mercapto group-containing trialkoxysilane include 3-mercaptopropyltrimethoxysilane.

[0155] Examples of the isocyanate group-containing trialkoxysilane include 3-isocyanatepropyltriethoxysilane.

[0156] Examples of the (meth)acryloyloxy group-containing trialkoxysilane include 3-(meth)acryloyloxypropyltrimethoxysilane and 3-(meth)acryloyloxypropyltriethoxysilane.

[0157] Examples of the alkenyl group include vinyl and allyl.

[0158] Examples of the alkenyl group-containing trialkoxysilane include vinyltrimethoxysilane and vinyltriethoxysilane.

[0159] Examples of the tetraalkoxysilane include tetramethoxysilane, tetramethoxysilane oligomer, tetraethoxysilane, and tetraethoxysilane oligomer.

[0160] The "hydrolysis partial condensate of polyalkoxysilane" refers to a hydrolysis condensate in which an alkoxy group is present. From the viewpoint of preventing gelation, the hydrolysis partial condensate of polyalkoxysilane is used instead of the hydrolysis complete condensate of polyalkoxysilane.

[0161] Examples of the degree of condensation (hydrolysis partial condensate) include 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 19, 17, 15, 14, 13, 12, 11, 10, 9, 5, 3, 2, 1.7, 1.5, 1.4, 1.2, 1.1, 1.01, etc. In one embodiment, the degree of condensation is preferably 1.01 to 1000, more preferably 1.01 to 100.

[0162] Examples of the weight average molecular weight (hydrolysis partial condensate) include 190,000, 170,000, 150,000, 130,000, 100,000, 90,000, 70,000, 50,000, 30,000, 20,000, 10,000, 9000, 7500, 5000, 2500, 1000, 900, 750, 500, 250, 200, 175, 160, 150, 125, 110, 100, etc. In one embodiment, the weight average molecular weight is preferably 100 to 190,000.

[0163] The hydrolysis partial condensate of polyalkoxysilane can be produced by hydrolyzing 100 parts by mass of polyalkoxysilane at a reaction temperature of 30°C to 60°C for 0.5 to 5.0 hours in the presence of 0 to 5 parts by mass of an acid catalyst or a base catalyst (preferably an acid catalyst) to partially condense the polyalkoxysilane.

[0164] Examples of the acid catalyst include nitric acid, hydrochloric acid, sulfurous acid, phosphoric acid, formic acid, and acetic acid.

[0165] Examples of the alkaline catalyst include sodium hydroxide, lithium hydroxide, potassium hydroxide, calcium hydroxide, and amine compounds.

[0166] Examples of the mass % content (hydrolysis partial condensate / electrical storage device binder aqueous solution) include 10 mass %, 9 mass %, 8 mass %, 7 mass %, 6 mass %, 5 mass %, 4.5 mass %, 4 mass %, 3.5 mass %, 3 mass %, 2.5 mass %, 2 mass %, 1.5 mass %, 1 mass %, 0.9 mass %, 0.5 mass %, 0.1 mass %, 0.09 mass %, 0.05 mass %, 0.03 mass %, 0.01 mass %, etc. In one embodiment, the content is preferably 0.01 mass % to 10 mass %.

[0167] <Other adhesives> In one embodiment, the electrical storage device binder aqueous solution may optionally contain a binder other than the water-soluble polymer (other binder). Other binders may be used alone or in combination of two or more.

[0168] Examples of other binders include diene copolymers, fluorine copolymers, amide-imide copolymers, and copolymers other than those listed above.

[0169] Examples of the diene copolymer include styrene-butadiene copolymers, polybutadiene polymers, acrylonitrile-butadiene copolymers, methyl methacrylate-butadiene copolymers, and carboxyl-modified styrene-butadiene copolymers.

[0170] Examples of the fluorine-based copolymer include polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), and ethylene-tetrafluoroethylene copolymer (ETFE).

[0171] Examples of the amide-imide copolymer include polyamide (PA), polyimide (PI), polyamideimide (PAI), and aromatic polyamide.

[0172] Examples of copolymers other than those mentioned above include polyurethane polymers, poly(meth)acrylate polymers, vinyl chloride polymers, vinyl acetate polymers, vinyl acetate-ethylene copolymers, polyethylene, polypropylene, polyethylene terephthalate, polystyrene polymers, alginic acid and / or its salts.

[0173] The content (other binders / water-soluble polymers) in parts by mass includes, for example, 100 parts by mass, 95 parts by mass, 90 parts by mass, 85 parts by mass, 80 parts by mass, 75 parts by mass, 70 parts by mass, 65 parts by mass, 60 parts by mass, 55 parts by mass, 50 parts by mass, 45 parts by mass, 40 parts by mass, 35 parts by mass, 30 parts by mass, 25 parts by mass, 20 parts by mass, 19 parts by mass, 17 parts by mass, 15 parts by mass, 13 parts by mass, 10 parts by mass, 9 parts by mass, 7 parts by mass, 5 parts by mass, 4 parts by mass, 2 parts by mass, 1 part by mass, 0 parts by mass, etc. In one embodiment, the content preferably includes 0 parts by mass to 100 parts by mass.

[0174] <Dispersion (emulsion)> In one embodiment, the aqueous solution of the electrical storage device binder may optionally contain a dispersion (emulsion). The dispersions (emulsions) may be used alone or in combination of two or more.

[0175] Examples of the dispersion (emulsion) include styrene-butadiene copolymer latex, polystyrene polymer latex, polybutadiene polymer latex, acrylonitrile-butadiene copolymer latex, polyurethane polymer latex, polymethyl methacrylate polymer latex, methyl methacrylate-butadiene copolymer latex, polyacrylate polymer latex, vinyl chloride polymer latex, vinyl acetate polymer latex, vinyl acetate-ethylene copolymer latex, polyethylene latex, carboxyl-modified styrene-butadiene copolymer resin latex, acrylic resin emulsion, polyethylene, polypropylene, polyethylene terephthalate, polyamide (PA), polyimide (PI), polyamideimide (PAI), aromatic polyamide, alginic acid and its salts, polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), ethylene-tetrafluoroethylene copolymer (ETFE), and the like.

[0176] The mass content (dispersion (emulsion) / water-soluble polymer) includes, for example, 100 mass parts, 95 mass parts, 90 mass parts, 85 mass parts, 80 mass parts, 75 mass parts, 70 mass parts, 65 mass parts, 60 mass parts, 55 mass parts, 50 mass parts, 45 mass parts, 40 mass parts, 35 mass parts, 30 mass parts, 25 mass parts, 20 mass parts, 19 mass parts, 17 mass parts, 15 mass parts, 13 mass parts, 10 mass parts, 9 mass parts, 7 mass parts, 5 mass parts, 4 mass parts, 2 mass parts, 1 mass part, 0 mass part, etc. In one embodiment, the content preferably includes 0 mass parts to 100 mass parts.

[0177] <Thickener> In one embodiment, the aqueous solution of the electrical storage device binder may optionally contain a thickener. The thickener may be used alone or in combination of two or more.

[0178] Examples of the thickener include cellulose polymers and / or salts thereof, polyvinyl alcohols, (modified) poly(meth)acrylic acid and / or salts thereof, polyethylene glycol, polyethylene oxide, polyvinyl pyrrolidone, oxidized starch, starch phosphate, casein, modified starch, hydrogenated acrylonitrile-butadiene copolymer, and the like.

[0179] Examples of the cellulose-based polymer and / or its salt include carboxymethyl cellulose, methyl cellulose, and hydroxypropyl cellulose.

[0180] Examples of the polyvinyl alcohols include copolymers of maleic acid (anhydride) and / or fumaric acid and vinyl alcohol.

[0181] The content (thickener / water-soluble polymer) in parts by mass includes, for example, 100 parts by mass, 95 parts by mass, 90 parts by mass, 85 parts by mass, 80 parts by mass, 75 parts by mass, 70 parts by mass, 65 parts by mass, 60 parts by mass, 55 parts by mass, 50 parts by mass, 45 parts by mass, 40 parts by mass, 35 parts by mass, 30 parts by mass, 25 parts by mass, 20 parts by mass, 19 parts by mass, 17 parts by mass, 15 parts by mass, 13 parts by mass, 10 parts by mass, 9 parts by mass, 7 parts by mass, 5 parts by mass, 4 parts by mass, 2 parts by mass, 1 part by mass, 0 parts by mass, etc. In one embodiment, the content is preferably 0 to 100 parts by mass.

[0182] <Additives> The aqueous solution of the electrical storage device binder may optionally contain an agent other than a water-soluble polymer, water, a partially hydrolyzed condensate of polyalkoxysilane, another binder, a dispersion (emulsion), or a thickener as an additive. The additive may be used alone or in combination of two or more.

[0183] Examples of the additives include a dispersant, a leveling agent, and an antioxidant.

[0184] Examples of the dispersant include anionic dispersants, cationic dispersants, nonionic dispersants, and polymer dispersants.

[0185] Examples of the leveling agent include surfactants and the like.

[0186] Examples of the surfactant include alkyl surfactants, silicone surfactants, fluorine surfactants, and metal surfactants.

[0187] Examples of the antioxidant include phenol compounds, hydroquinone compounds, organic phosphine compounds, sulfur compounds, phenylenediamine compounds, and polymer-type phenol compounds.

[0188] The "polymer type phenol compound" refers to a polymer having a phenol structure. The weight average molecular weight (polymer type phenol compound) is preferably 200 to 1,000, more preferably 600 to 700.

[0189] Examples of the content (additive / water-soluble polymer) include less than 5 parts by mass, less than 4 parts by mass, less than 2 parts by mass, less than 1 part by mass, less than 0.9 parts by mass, less than 0.5 parts by mass, less than 0.4 parts by mass, less than 0.2 parts by mass, less than 0.1 parts by mass, less than 0.09 parts by mass, less than 0.05 parts by mass, less than 0.04 parts by mass, less than 0.02 parts by mass, less than 0.01 parts by mass, and 0 parts by mass.

[0190] Examples of the mass % content (additive / electrical storage device binder aqueous solution) include less than 5 mass %, less than 4 mass %, less than 2 mass %, less than 1 mass %, less than 0.9 mass %, less than 0.5 mass %, less than 0.4 mass %, less than 0.2 mass %, less than 0.1 mass %, less than 0.09 mass %, less than 0.05 mass %, less than 0.04 mass %, less than 0.02 mass %, less than 0.01 mass %, and 0 mass %.

[0191] Examples of pH (electrical storage device binder aqueous solution) include 9, 8.9, 8.5, 8, 7.9, 7.5, 7, 6.9, 6.5, 6, 5.9, 5.6, 5.5, 5.4, 5.2, 5.1, and 5. In one embodiment, the pH is preferably 5-9, more preferably 5-7.

[0192] The measurement conditions (pH) are as follows. Measuring instrument: HORIBA, Ltd. (HORIBA, Ltd.) product name "pH meter D-52" Measurement temperature: 25℃

[0193] Applications (aqueous solution of binder for power storage devices) include, for example, aqueous solution of binder for power storage device electrodes, aqueous solution of binder for battery electrodes, aqueous solution of binder for non-aqueous secondary battery electrodes, aqueous solution of binder for lithium ion battery electrodes, aqueous solution of binder for sodium ion battery electrodes, aqueous solution of binder for negative electrode of power storage device, aqueous solution of binder for negative electrode of battery, aqueous solution of binder for negative electrode of non-aqueous secondary battery electrodes, aqueous solution of binder for negative electrode of lithium ion battery electrodes, aqueous solution of binder for negative electrode of sodium ion battery, aqueous solution of binder for positive electrode of power storage device, aqueous solution of binder for positive electrode of battery, aqueous solution of binder for positive electrode of non-aqueous secondary battery electrodes, aqueous solution of binder for positive electrode of lithium ion battery electrodes, aqueous solution of binder for positive electrode of sodium ion battery, aqueous solution of binder for separator of power storage device, aqueous solution of binder for separator of battery, aqueous solution of binder for separator of non-aqueous secondary battery electrodes, aqueous solution of binder for separator of lithium ion battery electrodes, aqueous solution of binder for separator of sodium ion battery electrodes, etc.

[0194] [Electricity storage device slurry: slurry] The present invention relates to a slurry for an electric storage device. The electrical storage device slurry comprises: a water-soluble polymer, (meth)acrylamide, (meth)acrylonitrile and water. The water-soluble polymer contains 0.01% to 1% by mass of a polymerization initiator unit. The content of the (meth)acrylamide is 0.01 ppm by mass or more and less than 1000 ppm by mass relative to the water-soluble polymer.

[0195] In this disclosure, "slurry" refers to a suspension of liquid and solid particles.

[0196] Examples of the water-soluble polymer, water, other binders, dispersions (emulsions), and thickeners include those mentioned above.

[0197] The mass % content (water-soluble polymer / slurry) includes, for example, 10 mass %, 9 mass %, 8 mass %, 7 mass %, 6 mass %, 5 mass %, 4 mass %, 3 mass %, 2 mass %, 1 mass %, 0.9 mass %, 0.7 mass %, 0.5 mass %, 0.3 mass %, 0.1 mass %, etc. In one embodiment, the content is preferably 0.1 mass % to 10 mass %.

[0198] Examples of the mass % content (water / slurry) include 80 mass %, 75 mass %, 70 mass %, 65 mass %, 60 mass %, 55 mass %, 50 mass %, 45 mass %, 40 mass %, 35 mass %, 30 mass %, etc. In one embodiment, the content is preferably 30 mass % to 80 mass %.

[0199] The mass % content (hydrolysis partial condensate / slurry) includes, for example, 5 mass %, 4.5 mass %, 4 mass %, 3.5 mass %, 3 mass %, 2.5 mass %, 2 mass %, 1.5 mass %, 1 mass %, 0.9 mass %, 0.5 mass %, 0.1 mass %, 0.09 mass %, 0.05 mass %, 0.03 mass %, 0.01 mass %, etc. In one embodiment, the content is preferably 0.01 mass % to 5 mass %.

[0200] The mass ppm content (sulfur / slurry) includes, for example, 1000 ppm, 950 ppm, 900 ppm, 850ppm, 800ppm, 750ppm, 700ppm, 650ppm, 600pp m, 550ppm, 500ppm, 450ppm, 400ppm, 350ppm, 300ppm, 250ppm, 200ppm, 150ppm, 100ppm, 90ppm, 75ppm, 50ppm, 25ppm, 15ppm, 14ppm, 13ppm, 11ppm, 10ppm, 9ppm, 7ppm, 5ppm, 3ppm, 1ppm, 0ppm, etc. In one embodiment, the content is preferably 1000ppm or less. The reasons for this are, for example, improved pencil hardness and improved breaking strength.

[0201] Examples of the content (polymerization initiator unit), the content ((meth)acrylamide), the content ((meth)acrylonitrile), the content (monomer), the content (other binders), the content (dispersion (emulsion)), and the content (thickener) include the above-mentioned contents.

[0202] <Electrode Active Material> In one embodiment, the electrical storage device slurry contains an electrode active material. Examples of the electrode active material include a negative electrode active material and a positive electrode active material. The electrode active material may be used alone or in combination of two or more.

[0203] (Negative electrode active material) Examples of the negative electrode active material include carbon materials, materials that can be alloyed with lithium, silicon materials, and oxides containing lithium atoms.

[0204] Examples of the carbon material include graphite, low-crystalline carbon, carbon black, fullerene, carbon nanotube, carbon nanofiber, carbon nanohorn, carbon fibril, mesocarbon microbeads (MCMB), pitch-based carbon fibers, and activated carbon.

[0205] Examples of graphite include natural graphite and artificial graphite.

[0206] Examples of low-crystalline carbon include soft carbon and hard carbon.

[0207] Examples of carbon black include Ketjen black, acetylene black, channel black, lamp black, oil furnace black, thermal black, and the like.

[0208] Examples of the material that alloys with lithium include lead compounds, tin compounds, arsenic compounds, antimony compounds, and aluminum compounds.

[0209] Silicon materials include silicon, silicon oxide, silicon alloy, SiC, SiO x C y (0<x≤3, 0<y≤5), Si3N4, Si2N2O, SiO z (0<z≤2) etc.

[0210] Silicon oxide preferably has a composition formula SiO z Silicon oxide represented by (0<z≤2, preferably 0.1≤z≤1).

[0211] Examples of silicon alloys include silicon-titanium alloys, silicon-zirconium alloys, silicon-nickel alloys, silicon-copper alloys, silicon-iron alloys, silicon-molybdenum alloys, etc. In one embodiment, the silicon alloy preferably includes silicon-nickel alloys and silicon-titanium alloys, and more preferably includes silicon-titanium alloys.

[0212] The mol% content (silicon atoms / total metal elements) is preferably 10 mol% or more, more preferably 20 mol% to 70 mol%.

[0213] Examples of the shape of the silicon material include single crystal, polycrystalline, and amorphous.

[0214] When a silicon material is used as the electrode active material, an electrode active material other than the silicon material may be used in combination.

[0215] Examples of electrode active materials other than silicon materials include carbon materials, conductive polymers, and composite metal oxides.

[0216] Examples of the conductive polymer include polyacene and the like.

[0217] The composite metal oxide is represented by, for example, the following general formula. A α B β O γ (A represents an alkali metal or a transition metal. B represents at least one transition metal selected from cobalt, nickel, aluminum, tin, manganese and the like. O represents an oxygen atom. α, β and γ are independently 0.05<α<1.10, 0.85<β<4.00, and 1.5<γ<5.00.)

[0218] Carbon materials have a small volume change associated with the absorption and release of lithium. Therefore, when a silicon material is used as an electrode active material, it is preferably used in combination with a carbon material.

[0219] In one embodiment, the silicon material preferably includes silicon covered with a carbon layer and silicon oxide covered with a carbon layer.

[0220] Examples of the lithium atom-containing oxide include lithium-transition metal composite oxides, lithium-transition metal phosphate compounds, and lithium-transition metal sulfate compounds.

[0221] Examples of the lithium-transition metal composite oxide include lithium-manganese composite oxide, lithium-nickel composite oxide, lithium-cobalt composite oxide, lithium-iron composite oxide, lithium-titanium composite oxide, lithium-nickel-manganese composite oxide, and lithium-nickel-cobalt composite oxide.

[0222] In one embodiment, mass % content (carbon material and / or material / negative electrode active material alloyed with lithium) for example, 100 mass %, 95 mass %, 90 mass %, 85 mass %, 80 mass %, 75 mass %, 70 mass %, 65 mass %, 60 mass %, 55 mass %, 50 mass %, 45 mass %, 40 mass %, 35 mass %, 30 mass %, 25 mass %, 20 mass %, 15 mass %, 10 mass %, 5 mass %, 0 mass %, etc. In one embodiment, the content preferably cites more than 50 mass %, more preferably cites more than 80 mass %, further preferably cites more than 90 mass %, and particularly preferably cites 100 mass %.

[0223] In one embodiment, the mass % content (silicon covered by the carbon layer and / or silicon oxide covered by the carbon layer / negative electrode active material) is, for example, 100 mass %, 90 mass % or more, 75 mass % or more, 50 mass % or more, 25 mass % or more, 10 mass % or more, 5 mass % or more, 2 mass % or more, 1 mass % or more, 0 mass %, etc.

[0224] In one embodiment, the mass % content (silicon material / negative electrode active material) is, for example, 100 mass %, 95 mass %, 90 mass %, 85 mass %, 80 mass %, 75 mass %, 70 mass %, 65 mass %, 60 mass %, 55 mass %, 50 mass %, 45 mass %, 40 mass %, 35 mass %, 30 mass %, 25 mass %, 20 mass %, 15 mass %, 10 mass %, 5 mass %, 0 mass %, etc.

[0225] (Positive electrode active material) Examples of the positive electrode active material include positive electrode inorganic active materials and positive electrode organic active materials.

[0226] Examples of the positive electrode inorganic active material include transition metal oxides, lithium-transition metal composite oxides, transition metal sulfides, activated carbon, and the like.

[0227] The inorganic active material may be partially substituted with an element. By allowing a carbon source material to be present during reduction firing, the inorganic active material can be used as an electrode active material covered with a carbon material.

[0228] Examples of the positive electrode organic active material include conductive polymers.

[0229] Examples of the conductive polymer include polyacetylene and poly-p-phenylene.

[0230] (Physical properties, etc. (electrode active material)) Examples of the shape (electrode active material) include fine particle shape and thin film shape.

[0231] The average particle size (electrode active material) is preferably 0.1 to 50 μm, more preferably 0.1 to 45 μm, further preferably 1 to 10 μm, and particularly preferably 5 μm.

[0232] In the present disclosure, "particle size" refers to the maximum distance between any two points on the contour line of a particle. "Average particle size" refers to a value calculated as the average value of the particle sizes of particles observed in several to dozens of fields of view using an observation method such as a scanning electron microscope (SEM) or a transmission electron microscope (TEM).

[0233] The content (water-soluble polymer / electrode active material) in parts by mass includes 15 parts by mass, 14 parts by mass, 13 parts by mass, 12 parts by mass, 11 parts by mass, 10 parts by mass, 9 parts by mass, 8 parts by mass, 7 parts by mass, 6 parts by mass, 5 parts by mass, 4 parts by mass, 3 parts by mass, 2 parts by mass, 1.5 parts by mass, 1 part by mass, 0.5 parts by mass, etc. In one embodiment, the content is preferably 0.5 parts by mass to 15 parts by mass.

[0234] (Conductive additive) In one embodiment, the slurry may optionally include a conductive additive. The conductive additive may be used alone or in combination of two or more.

[0235] Examples of the conductive additive include fibrous carbon, carbon black, and metal fine powder.

[0236] Examples of fibrous carbon include vapor grown carbon fibers (VGCF), carbon nanotubes (CNTs), and carbon nanofibers (CNFs).

[0237] Examples of carbon black include graphite particles, acetylene black, Ketjen black, furnace black, and the like.

[0238] Examples of the metal fine powder include copper fine powder, nickel fine powder, aluminum fine powder, silicon fine powder, and alloy fine powder.

[0239] In one embodiment, the average particle size (metal fine powder) is preferably 10 μm.

[0240] The content (conductive aid / electrode active material) is preferably 0 to 10 parts by mass, more preferably 0 to 6 parts by mass.

[0241] <Non-conductive particles> In one embodiment, the electrical storage device slurry contains non-conductive particles. The non-conductive particles may be used alone or in combination of two or more.

[0242] Examples of the non-conductive particles include oxide particles, hydroxide particles, nitride particles, covalent crystal particles, poorly soluble ion crystal particles, clay fine particles, aluminum particles, barium particles, and calcium particles.

[0243] Examples of oxide particles include aluminum oxide (alumina), aluminum oxide hydrate (boehmite (AlOOH), gibbsite (Al(OH)3), bakelite), iron oxide, silicon oxide, magnesium oxide (magnesia), calcium oxide, titanium oxide (titanium oxide), BaTiO3, ZrO, aluminum oxide-silicon dioxide composite oxides, etc.

[0244] Examples of the hydroxide particles include calcium hydroxide and magnesium hydroxide.

[0245] Examples of nitride particles include aluminum nitride, silicon nitride, and boron nitride.

[0246] Examples of covalent crystals include silicon and diamond.

[0247] Examples of the poorly soluble ion crystals include barium sulfate, calcium fluoride, and barium fluoride.

[0248] Examples of the clay fine particles include clay fine particles such as silica, talc, and montmorillonite.

[0249] Examples of aluminum particles include alumina (alumina), alumina hydrate (boehmite (AlOOH), gibbsite (Al(OH) 3 ), and aluminum nitride.

[0250] Examples of the barium particles include barium sulfate and barium fluoride.

[0251] Examples of the calcium particles include calcium hydroxide, magnesium hydroxide, and calcium fluoride.

[0252] In one embodiment, preferred non-conductive particles include boehmite, aluminum oxide, magnesium oxide, and barium sulfate.

[0253] Examples of the average particle size (non-conductive particles) include 30 μm, 25 μm, 20 μm, 15 μm, 10 μm, 5 μm, 1 μm, 0.5 μm, 0.1 μm, 0.05 μm, and 0.01 μm. In one embodiment, the average particle size is preferably 0.01 μm to 30 μm.

[0254] The mass % content (non-conductive particles / paste) includes, for example, 99.9 mass %, 95 mass %, 90 mass %, 80 mass %, 70 mass %, 60 mass %, 50 mass %, 40 mass %, 30 mass %, 20 mass %, 10 mass %, 5 mass %, 1 mass %, 0.5 mass %, 0.2 mass %, 0.1 mass %, etc. In one embodiment, the content is preferably 0.1 mass % to 99.9 mass %.

[0255] The content (water-soluble polymer / non-conductive particles) in parts by mass includes, for example, 15 parts by mass, 14 parts by mass, 13 parts by mass, 12 parts by mass, 11 parts by mass, 10 parts by mass, 9 parts by mass, 8 parts by mass, 7 parts by mass, 6 parts by mass, 5 parts by mass, 4 parts by mass, 3 parts by mass, 2 parts by mass, 1.5 parts by mass, 1 part by mass, etc. In one embodiment, the content is preferably 1 to 15 parts by mass, more preferably 1.5 to 14 parts by mass, and even more preferably 2 to 12 parts by mass.

[0256] <Slurry Viscosity Adjusting Solvent> The slurry viscosity adjusting solvent may be used alone or in combination of two or more.

[0257] Examples of the slurry viscosity adjusting solvent include amide solvents, hydrocarbon solvents, alcohol solvents, ketone solvents, ether solvents, ester solvents, amine solvents, lactone solvents, sulfoxide / sulfone solvents, and water.

[0258] Examples of the amide solvent include N-methylpyrrolidone, dimethylformamide, and N,N-dimethylacetamide.

[0259] Examples of the hydrocarbon solvent include toluene, xylene, n-dodecane, and tetralin.

[0260] Examples of the alcohol solvent include methanol, ethanol, 2-propanol, isopropanol, 2-ethyl-1-hexanol, 1-nonanol, and lauryl alcohol.

[0261] Examples of the ketone solvent include acetone, methyl ethyl ketone, cyclohexanone, phorone, acetophenone, and isophorone.

[0262] Examples of the ether solvent include dioxane and tetrahydrofuran (THF).

[0263] Examples of the ester solvent include benzyl acetate, isoamyl butyrate, methyl lactate, ethyl lactate, and butyl lactate.

[0264] Examples of the amine solvent include o-toluidine, m-toluidine, and p-toluidine.

[0265] Examples of the lactone solvent include γ-butyrolactone and δ-butyrolactone.

[0266] Examples of the sulfoxide / sulfone solvent include dimethyl sulfoxide and sulfolane.

[0267] In one embodiment, the slurry viscosity adjusting solvent is preferably N-methylpyrrolidone.

[0268] Examples of the mass % content (slurry viscosity adjusting solvent / slurry) include 10 mass %, 9 mass %, 8 mass %, 7 mass %, 6 mass %, 5 mass %, 4 mass %, 3 mass %, 2 mass %, 1 mass %, 0 mass %, etc. In one embodiment, the content is preferably 0 to 10 mass %.

[0269] <Additives> The slurry may optionally contain an agent other than a water-soluble polymer, water, other binders, dispersions (emulsions), thickeners, electrode active materials, non-conductive particles, and slurry viscosity adjusting solvents as additives. Examples of the additives include the above-mentioned agents.

[0270] Examples of the mass % content (additive / slurry) include 0 mass % to 5 mass %, less than 1 mass %, less than 0.1 mass %, less than 0.01 mass %, and 0 mass %.

[0271] The content by mass of (additive / water-soluble polymer), the content by mass of (additive / water), the content by mass of (additive / hydrolyzed partial condensate of polyalkoxysilane), the content by mass of (additive / other binders), the content by mass of (additive / dispersion (emulsion)), the content by mass of (additive / thickener), the content by mass of (additive / electrode active material), the content by mass of (additive / non-conductive particles), the content by mass of (additive / slurry viscosity adjusting solvent) includes, for example, 0 to 5 parts by mass, less than 1 part by mass, less than 0.1 part by mass, less than 0.01 part by mass, 0 part by mass, etc.

[0272] The slurry can be produced by mixing a water-soluble polymer, water, an electrode active material or non-conductive particles, and, if necessary, a hydrolyzed partial condensate of polyalkoxysilane, other binders, a dispersion (emulsion), a thickener, a slurry viscosity adjusting solvent, and additives.

[0273] Examples of the mixing means (slurry) include a ball mill, a sand mill, a pigment disperser, a pounder, an ultrasonic disperser, a homogenizer, a planetary mixer, and a Hobart mixer.

[0274] Examples of the use (electrical storage device slurry) include electrical storage device electrode slurry, battery electrode slurry, non-aqueous secondary battery electrode slurry, lithium ion battery electrode slurry, sodium ion battery electrode slurry, electrical storage device negative electrode slurry, battery negative electrode slurry, non-aqueous secondary battery negative electrode slurry, lithium ion battery negative electrode slurry, sodium ion battery negative electrode slurry, electrical storage device positive electrode slurry, battery positive electrode slurry, non-aqueous secondary battery positive electrode slurry, lithium ion battery positive electrode slurry, sodium ion battery positive electrode slurry, electrical storage device diaphragm slurry, battery diaphragm slurry, non-aqueous secondary battery diaphragm slurry, lithium ion battery diaphragm slurry, sodium ion battery diaphragm slurry, etc.

[0275] [Electrodes for power storage devices: Electrodes] The present disclosure relates to an electric storage device electrode having a dried product of the electric storage device slurry on a current collector.

[0276] The electric storage device electrode is obtained by applying the electric storage device slurry onto a current collector and drying the slurry.

[0277] Examples of the current collector include metal materials and carbon materials.

[0278] Examples of the metal material include copper, iron, aluminum, nickel, stainless steel, and nickel-plated steel.

[0279] Examples of the form of the metal material include metal foil, metal cylinder, metal coil, and metal plate.

[0280] Examples of the carbon material include carbon cloth and carbon paper.

[0281] Examples of the form (carbon material) include a carbon plate, a carbon film, and a carbon cylinder.

[0282] Examples of coating means include a comma coater, a gravure coater, a micro gravure coater, a die coater, and a rod coater.

[0283] The drying temperature is preferably 60°C to 200°C, more preferably 70°C to 195°C.

[0284] Examples of the dry atmosphere include dry air and an inert atmosphere.

[0285] The thickness (electrode (cured product)) is preferably 5 μm to 300 μm, more preferably 10 μm to 250 μm.

[0286] Examples of uses (electrical storage device electrodes) include electric storage device positive electrodes, electric storage device negative electrodes, battery electrodes, battery positive electrodes, battery negative electrodes, non-aqueous secondary battery electrodes, non-aqueous secondary battery positive electrodes, non-aqueous secondary battery negative electrodes, lithium ion battery electrodes, lithium ion battery positive electrodes, lithium ion battery negative electrodes, sodium ion battery electrodes, sodium ion battery positive electrodes, sodium ion battery negative electrodes, etc.

[0287] [Electricity storage device diaphragm: diaphragm] The present disclosure relates to an electric storage device separator having a dried product of the electric storage device slurry on a substrate.

[0288] The electrical storage device separator can be produced by applying the electrical storage device separator slurry on one side or both sides of a substrate and drying the slurry.

[0289] Examples of the substrate include porous polyolefin resin substrates and plastic nonwoven fabrics.

[0290] (Porous polyolefin resin substrate) The “porous polyolefin resin substrate” refers to a microporous film containing 30% by mass or more of a resin such as polyolefin or a mixture or copolymer thereof.

[0291] The polyolefin resin may be used alone or in combination of two or more. Examples of the polyolefin resin include homopolymers and copolymers of ethylene, propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, and 1-octene.

[0292] Examples of the stereostructure (polyolefin) include isotactic, syndiotactic and atactic.

[0293] In one embodiment, the polyolefin resin preferably includes high-density polyethylene, and more preferably includes high-density polyethylene and polypropylene.

[0294] In one embodiment, the mass % content (polyolefin resin / substrate) is preferably 30 mass % to 100 mass %, more preferably 40 mass % to 100 mass %, and further preferably 50 mass % to 100 mass %.

[0295] The porous polyolefin resin substrate may optionally contain fillers and fiber compounds. The strength, hardness and thermal shrinkage of the porous polyolefin resin substrate may be controlled by fillers and fiber compounds.

[0296] The porous polyolefin resin substrate may be surface-treated as necessary.

[0297] Examples of the surface treatment include coating treatment, electromagnetic wire treatment, and plasma treatment.

[0298] In one embodiment, the surface treatment preferably includes coating treatment with a polymer containing a polar group. The coating treatment can improve the electrolyte impregnation and adhesion to the dried slurry. Examples of polar groups include carboxylic acid groups, hydroxyl groups, and sulfonic acid groups.

[0299] In one embodiment, the thickness (porous polyolefin resin substrate) is preferably 2 μm to 100 μm, more preferably 5 μm to 50 μm.

[0300] (Plastic non-woven fabric) Examples of the plastic nonwoven fabric include nonwoven fabrics made of only synthetic fibers.

[0301] Examples of synthetic fibers include polyolefin resins, polyester resins, acrylonitrile resins, polyamide resins, polyvinyl acetate resins, ethylene-vinyl acetate copolymer resins, acrylic resins, polyvinyl chloride resins, polyvinylidene chloride resins, polyvinyl ether resins, polyvinyl ketone resins, polyether resins, polyvinyl alcohol resins, diene resins, polyurethane resins, phenol resins, melamine resins, furan resins, urea resins, aniline resins, unsaturated polyester resins, alkyd resins, fluorine resins, silicone resins, polyamide-imide resins, polyphenylene sulfide resins, polyimide resins, polycarbonate resins, polyazine resins, polyesteramide resins, polyetheretherketone resins, polyparaphenylenebenzobisoxazole resins, polybenzimidazole resins, and ethylene-vinyl alcohol copolymer resins.

[0302] Examples of the polyolefin-based resin include polypropylene, polyethylene, polymethylpentene, ethylene-vinyl alcohol copolymer, and olefin-based copolymers.

[0303] Examples of the polyester resin include polyethylene terephthalate (PET) resin, polybutylene terephthalate (PBT) resin, polypropylene terephthalate (PPT) resin, polyethylene naphthalate (PEN) resin, polybutylene naphthalate resin, polyethylene isonaphthalate resin, and wholly aromatic polyester resins.

[0304] Examples of the acrylonitrile-based resin include polyacrylonitrile and copolymers of acrylonitrile and a (meth)acrylic acid derivative, vinyl acetate, and the like.

[0305] Examples of the polyamide-based resin include aliphatic polyamide, wholly aromatic polyamide, and semi-aromatic polyamide.

[0306] Examples of aliphatic polyamide include nylon and the like.

[0307] Examples of the wholly aromatic polyamide include poly(p-phenylene terephthalamide), poly(p-phenylene terephthalamide-3,4-diphenyl ether terephthalamide), and poly(meta-phenylene isophthalamide).

[0308] The "semi-aromatic polyamide" refers to a polyimide in which a part of the main chain of the aromatic polyamide is an aliphatic chain.

[0309] The plastic nonwoven fabric fibers may optionally contain fibers other than synthetic resin fibers.

[0310] Examples of fibers other than synthetic resin fibers include solvent-spun cellulose, fibrillated products of solvent-spun cellulose, regenerated cellulose, fibrillated products of regenerated cellulose, natural cellulose fibers, pulped products of natural cellulose fibers, fibrillated products of natural cellulose fibers, and inorganic fibers.

[0311] The mass % content (fibers other than synthetic fibers / nonwoven fabric) is preferably 50 mass % or less, more preferably 30 mass % or less, and further preferably 10 mass % or less.

[0312] Examples of the form (form) include single fibers and composite fibers.

[0313] "Single fiber" refers to a fiber formed of a single resin. "Conjugate fiber" refers to a fiber formed of two or more resins.

[0314] Examples of the form (composite fiber) include core-sheath type, eccentric core type, side-by-side type, island-in-the-sea type, segmented-orange type, and bimetallic laminated type (multiple bimetallic type).

[0315] In one embodiment, the average fiber diameter (plastic nonwoven fabric) is preferably 1 μm to 15 μm, more preferably 1 μm to 10 μm.

[0316] The “average fiber diameter” refers to the average value of the fiber diameters of 20 fibers randomly selected from a scanning electron microscope photograph.

[0317] In one embodiment, the average pore diameter (plastic nonwoven fabric) is preferably 1 μm to 20 μm, more preferably 3 μm to 20 μm, and even more preferably 5 μm to 20 μm.

[0318] The "pore size" refers to the width of the gap between fibers. The "average pore size" refers to the average value of the pore sizes of 20 fibers randomly selected from a scanning electron microscope photograph.

[0319] In one embodiment, the thickness (plastic nonwoven fabric) is preferably 5 μm to 25 μm, more preferably 5 μm to 15 μm.

[0320] <Manufacturing method (electricity storage device diaphragm)> Examples of the production method (electrical storage device separator) include a method including a coating step of coating an electric storage device separator slurry on a substrate and a drying step of drying the coated electric storage device separator slurry.

[0321] (Coating process) Examples of the coating method include a coating method, a printing method, a transfer method, and a dipping method.

[0322] Examples of coating methods include a doctor blade, a rod, a reverse roll, a lip, a die, a curtain, and an air knife.

[0323] Examples of printing methods include flexographic printing, screen printing, offset printing, gravure printing, and inkjet printing.

[0324] Examples of the transfer method include roller transfer and film transfer.

[0325] Examples of the impregnation method include dipping.

[0326] (Drying process) Examples of the drying method include air drying, irradiation drying, and vacuum drying.

[0327] Examples of air drying include warm air drying, hot air drying, and low-humidity air drying.

[0328] Examples of irradiation drying include infrared irradiation drying, far infrared irradiation drying, and electron beam irradiation drying.

[0329] The drying temperature is preferably 40°C to 90°C, more preferably 50°C to 80°C.

[0330] The drying time is preferably 5 seconds to 3 minutes, more preferably 15 seconds to 2 minutes.

[0331] The manufacturing method (electrical storage device separator) may optionally include a pressing step.

[0332] Examples of the pressing means include die pressing and roll pressing.

[0333] The electrical storage device separator can be used as, for example, a battery separator, a non-aqueous secondary battery separator, a lithium ion battery separator, a sodium ion battery separator, and the like.

[0334] [Electrode stack for power storage devices] The present disclosure relates to an electric storage device separator / electrode stack having a dried product of the electric storage device slurry on an active material side of an electrode.

[0335] The electric storage device separator / electrode laminate is obtained by applying the electric storage device slurry onto an electrode and drying the resultant.

[0336] The production method (electrical storage device separator / electrode stack) includes, for example, a method including the following steps. (1) Step of coating a slurry containing an electrode material on a current collector (2) Step of drying the slurry containing the electrode material (3) Step of pressing the dried product of the slurry containing the electrode material (4) Step of applying the electrical storage device separator slurry onto the dried product of the slurry containing the electrode material (5) Step of drying the electrical storage device diaphragm slurry

[0337] Examples of the coating method, drying method and pressing method include the above-mentioned methods.

[0338] Uses (electrical storage device separator / electrode stack) include, for example, battery separator / electrode stack, battery separator / negative electrode stack, battery separator / positive electrode stack, non-aqueous secondary battery separator / electrode stack, non-aqueous secondary battery separator / negative electrode stack, non-aqueous secondary battery separator / positive electrode stack, lithium ion battery separator / electrode stack, lithium ion battery separator / negative electrode stack, lithium ion battery separator / positive electrode stack, sodium ion battery separator / electrode stack, sodium ion battery separator / negative electrode stack, sodium ion battery separator / positive electrode stack, etc.

[0339] [Electricity storage equipment] The present disclosure relates to an electric storage device.

[0340] In one embodiment, the electrical storage device includes the electrical storage device electrode.

[0341] In one embodiment, the electric storage device includes the electric storage device separator.

[0342] In one embodiment, the electrical storage device includes the electrical storage device separator / electrode stack.

[0343] (Electrolyte) The power storage device may optionally contain an electrolyte solution. Examples of the electrolyte solution include a solution in which a supporting electrolyte is dissolved in a non-aqueous solvent.

[0344] The non-aqueous solvents may be used alone or in combination of two or more.

[0345] Examples of the non-aqueous solvent include chain carbonate solvents, cyclic carbonate solvents, chain ether solvents, cyclic ether solvents, chain ester solvents, cyclic ester solvents, and acetonitrile.

[0346] Examples of the chain carbonate solvent include diethyl carbonate, dimethyl carbonate, and ethyl methyl carbonate.

[0347] Examples of the cyclic carbonate solvent include ethylene carbonate, propylene carbonate, and butylene carbonate.

[0348] Examples of the chain ether solvent include 1,2-dimethoxyethane.

[0349] Examples of the cyclic ether solvent include tetrahydrofuran, 2-methyltetrahydrofuran, sulfolane, and 1,3-dioxolane.

[0350] Examples of the chain ester solvent include methyl formate, methyl acetate, and methyl propionate.

[0351] Examples of the cyclic ester solvent include γ-butyrolactone and γ-valerolactone.

[0352] In one embodiment, the non-aqueous solvent preferably includes a combination of a cyclic carbonate and a chain carbonate.

[0353] The supporting electrolyte may be used alone or in combination of two or more.

[0354] Examples of supporting electrolytes include lithium salts. Examples of lithium salts include LiPF6, LiAsF6, LiBF4, LiS bF6, LiAlCl4, LiClO4, CF3SO3Li, C4F9SO3Li, CF3COOL i, (CF3CO)2NLi, (CF3SO2)2NLi, (C2F5SO2)NLi, etc. In one embodiment, the supporting electrolyte preferably includes LiPF6, LiClO4, and CF3SO3Li.

[0355] In one embodiment, the non-aqueous electrolyte solution may optionally contain a coating film forming agent. The coating film forming agent may be used alone or in combination of two or more.

[0356] Examples of the film-forming agent include carbonates, cyclosulfides, sultones, and acid anhydrides.

[0357] Examples of the carbonate ester include vinylene carbonate, vinylethylene carbonate, vinylethyl carbonate, methylphenyl carbonate, fluoroethylene carbonate, and difluoroethylene carbonate.

[0358] Examples of alkyl sulfides include ethylene sulfide and propylene sulfide.

[0359] Examples of sultone include 1,3-propane sultone and 1,4-butane sultone.

[0360] Examples of the acid anhydride include maleic anhydride and succinic anhydride.

[0361] In one embodiment, the mass % content (film forming agent / electrolyte) is preferably 10 mass % or less, more preferably 8 mass % or less, further preferably 5 mass % or less, and particularly preferably 2 mass % or less.

[0362] Examples of the form (electricity storage device) include a cylindrical type in which an electrode sheet and a separator are spirally formed; a cylindrical type with an inside-out structure in which a plate electrode and a separator are combined; and a button type in which a plate electrode and a separator are stacked.

[0363] As a manufacturing method (electricity storage device), for example, there is a method described in Japanese Patent Application Laid-Open No. 2013-089437.

[0364] Examples of applications (electricity storage devices) include batteries, non-aqueous secondary batteries, lithium ion batteries, sodium ion batteries, and the like. Example

[0365] The present invention is specifically described below by way of examples and comparative examples. However, the above description and the following examples are not intended to limit the purpose of the present invention. The present invention is limited to the scope of the claims. Unless otherwise specified, the values ​​of parts, % and the like are by mass.

[0366] Example 1 733.6 g of ion exchange water, 100 g (40 mol%) of 50% acrylamide, 47.5 g (30 mol%) of 80% acrylic acid, and 28.0 g (30 mol%) of acrylonitrile were added to a reaction apparatus equipped with a stirrer, a thermometer, a reflux cooling tube, a nitrogen inlet tube, and three dropping funnels. After removing oxygen from the reaction system by nitrogen, the temperature was raised to 55°C. 0.116 g (0.1 mass%) of 2,2'-azobis-2-amidinopropane dihydrochloride (product name "NC-32P" manufactured by Nihon Chemical Co., Ltd.) and 5 g of ion exchange water were added thereto, and the temperature was raised to 80°C for 3 hours of reaction. Next, 1.16 g (1% by mass) of 2,2′-azobis-2-amidinopropane dihydrochloride (product name “NC-32P” manufactured by Nihon Chemical Co., Ltd.) was added and reacted at 80° C. for 2 hours to prepare an aqueous solution of a power storage device binder.

[0367] Unless otherwise specified, the following examples were carried out in the same manner as in Example 1 except that the changes were made as shown in the table.

[0368] <Production of Hydrolyzed Partial Condensate of Polyalkoxysilane> In a reaction apparatus equipped with a stirrer, a thermometer, a reflux cooling tube, and a nitrogen inlet tube, 100 g of ion exchange water, 100 g of methanol, and 200 g of 3-aminopropyltrimethoxysilane (product name "KBM-903" manufactured by Shin-Etsu Chemical Co., Ltd.) were added, and the reaction was carried out at 25°C for 0.5 hour to obtain a uniform aqueous solution of a hydrolyzed partial condensate of polyalkoxysilane having a condensation degree of 1.4 and a weight average molecular weight of 160.

[0369] When the amount of Si-HC in the table is not 0, the hydrolyzed partial condensate of the polyalkoxysilane was added to the aqueous solution in the amount described in the following table, and then stirred for 30 minutes to obtain an aqueous solution.

[0370] [Table 1]

[0371] AM: Acrylamide AA: Acrylic acid AN: Acrylonitrile SMAS: Sodium methallyl sulfonate ·Na: sodium hydroxide ·Ca: Calcium hydroxide ·Si-HC: Hydrolysis partial condensation product of polyalkoxysilane ·APS: Ammonium Persulfate ·SPS: Sodium Persulfate ·KPS: Potassium Persulfate The "neutralization ratio" refers to a ratio relative to 100 mol% of the carboxyl groups in the acrylic acid unit.

[0372] The monomer content was determined as follows. (1) Preparation (standard solution) Monomers ((meth)acrylamide, (meth)acrylonitrile) were collected in 20 mL spiral tubes and diluted with ultrapure water to prepare standard aqueous solutions of 2000 ppm, 1000 ppm, 500 ppm, 100 ppm, 10 ppm, 1 ppm, and 0.5 ppm. (2) Calibration curve of (meth)acrylamide The standard solution was used to perform measurement under the following conditions to prepare a calibration curve. Measurement instrument: HPLC (Agilent 1260Infinity2 PrimeLC) Column: InertSustain AQ-C18 Column oven temperature: 40°C Eluent: Phosphate buffer (sodium dihydrogen phosphate / ultrapure water = 8 / 1000 (v / v) aqueous solution) Measurement concentration: 0.20 mass% (water-soluble polymer concentration) Injection volume: 4 μL (3) Preparation (sample) Each sample was diluted 50 times in a spiral tube and measured under the conditions of (2), and the monomer content in the sample was calculated based on the calibration curve.

[0373] <Breaking strength> The aqueous solution of the power storage device binder was applied on the surface of a polypropylene flat plate, and heated in an oven at 120° C. until the weight reached a constant, thereby obtaining a non-volatile component of the aqueous solution of the power storage device binder as a residue. The obtained non-volatile component was formed into a size of 50 mm in length, 20 mm in width, and 50 μm in thickness, thereby preparing a formed film composed of the non-volatile component of the aqueous solution of the power storage device binder. The breaking strength of the produced formed film was measured at a tensile speed of 50 mm / min using a universal testing machine (AGX-V, manufactured by Shimadzu Corporation). A:30MPa or above B: less than 30MPa

[0374] <Pencil hardness> The adhesive aqueous solution was applied under the following conditions and dried to produce a film. The pencil hardness (film) was measured by the following test method. Substrate: Glass plate Coating method: Coater (thickness 200μm) Drying conditions: 100°C, 30 minutes Test method: General test method of JIS K-5401 A: 3 hours or more B: 2 hours or less

[0375] <Operation evaluation (electricity storage device electrodes)> (1-1) Manufacturing (Electrode slurry for power storage devices) Using a commercially available planetary mixer (product name: "Awatori Ren Tarou", manufactured by Thinky Corporation), 7 parts by mass of the aqueous solution of the power storage device adhesive obtained in the examples (in terms of non-volatile components), 50 parts by mass of silicon oxide particles with a D50 of 5 μm, and 50 parts by mass of natural graphite (product name: "Z-5F", manufactured by Ito Graphite Industry Co., Ltd.) were mixed in a container dedicated to this mixer. Ion-exchanged water was added thereto to make the non-volatile component concentration 40%, and the container was placed in the above-mentioned mixer. Then, after kneading at 2000 rpm for 10 minutes, defoaming was carried out for 1 minute to obtain the power storage device electrode paste.

[0376] (1-2) Manufacturing (Power Storage Device Electrode) On the surface of the current collector composed of a copper foil, the above-mentioned power storage device electrode paste was uniformly coated by the doctor blade method so that the dried film thickness was 25 μm. After drying at 80 °C for 30 minutes, heat treatment was carried out at 100 °C for 60 minutes to obtain the electrode. Then, pressing was carried out by a roll press so that the density of the film (electrode active material layer) was 1.2 g / cm 3 , thereby obtaining the electrode.

[0377] (1-3) Manufacturing (Power Storage Device) Inside a glove box purged with argon, the above-mentioned electrode was punched into a component with a diameter of 16 mm and placed on a bipolar button cell (manufactured by Hokuen Co., Ltd., product name: "HS Flat Cell"). Then, a separator composed of a porous polypropylene film punched into a diameter of 24 mm (manufactured by CS TECH CO., LTD, product name: "SelionP2010") was placed, and further 500 μL of electrolyte was injected in a manner that no air entered. Then, a component obtained by punching a commercially available lithium metal foil into 16 mm was placed, and the outer package body of the above-mentioned bipolar button cell was sealed with a screw, thereby assembling the power storage device (lithium half-cell). The electrolyte used here is a solution in which LiPF6 is dissolved at a concentration of 1 mol / L in a solvent of ethylene carbonate / dimethyl carbonate = 3 / 7 (volume ratio).

[0378] (1-4) Charge and Discharge Measurement The lithium half-cell was placed in a thermostat at 25 °C, and charging was started at a constant current (0.1C) and completed (cut off) at the time point when the voltage reached 0.01V. Then, discharging was started at a constant current (0.1C) and completed (cut off) at the time point when the voltage reached 1.0V, and such charge and discharge were repeated 30 times. In addition, "1C" in the above measurement conditions refers to the current value when a battery with a certain capacitance is discharged at a constant current for 1 hour. For example, "0.1C" refers to the current value when the discharge takes 10 hours, and "10C" refers to the current value when the discharge takes 0.1 hour.

[0379] <First Coulombic efficiency> The first coulombic efficiency was calculated from the first charge capacity (mAh) and the first discharge capacity (mAh) in the charge-discharge cycle test at room temperature (25° C.) using the following formula. First coulombic efficiency = (first discharge capacity) / (first charge capacity) × 100 (%) A:More than 65% B: 60% or more and less than 65% C: Less than 60%

[0380] <Discharge capacity maintenance rate> The discharge capacity retention rate was calculated by the following formula. Discharge capacity retention rate = {(discharge capacity at the 30th cycle) / (discharge capacity at the 1st cycle)}×100 (%) A:More than 80% B: 75% or more and less than 80% C: less than 75%

[0381] <Operational evaluation (electrical storage device diaphragm)> (2-1) Manufacturing (slurry for diaphragm of power storage device) 5 parts by mass of the storage device binder aqueous solution (calculated as non-volatile components) obtained in the example and 113 parts by mass of water were stirred and mixed, 100 parts by mass of boehmite (average particle size 0.8 μm) as non-conductive particles were added, and the mixture was dispersed and stirred at 15000 rpm for 60 minutes using a homogenizer (T25 digital ULTRA-TURRAX manufactured by IKA). Ion exchange water was further added to adjust the viscosity to prepare a storage device diaphragm slurry.

[0382] (2-2) Manufacturing (Separator): Lamination of Separator Slurry Layers (Coating Layers) A single-layer polyethylene separator substrate (PE substrate) having a width of 250 mm, a length of 200 mm, and a thickness of 6 μm was prepared by a wet process. The storage device separator slurry was applied to one surface of the separator using a gravure coater to a thickness of 3.0 μm after drying, and dried to obtain a storage device separator.

[0383] (2-3) Manufacturing (electricity storage equipment) In the above (1-3) Production (Electricity Storage Device), an electricity storage device is produced by the same method except that the separator produced above is used.

[0384] The electrical storage device having the electrical storage device separator produced using the electrical storage device binder aqueous solution of the example functioned without any problem.

Claims

1. An aqueous solution of an electrical storage device binder, The storage device binder aqueous solution comprises: a water-soluble polymer, (meth)acrylamide and (meth)acrylonitrile, The water-soluble polymer contains 0.01% to 1% by mass of a polymerization initiator unit. The content of the (meth)acrylamide is 0.01 ppm by mass or more and less than 1000 ppm by mass relative to the water-soluble polymer.

2. A slurry for an electrical storage device, The electrical storage device slurry comprises: a water-soluble polymer, (meth)acrylamide, (meth)acrylonitrile and water. The water-soluble polymer contains 0.01% to 1% by mass of a polymerization initiator unit. The content of the (meth)acrylamide is 0.01 ppm by mass or more and less than 1000 ppm by mass relative to the water-soluble polymer. The electrical storage device slurry according to claim 2 , comprising an electrode active material. The electrical storage device slurry according to claim 2 , comprising non-conductive particles. 5 . An electric storage device electrode comprising a dried product of the electric storage device slurry according to claim 2 or 3 on a current collector. 6 . An electric storage device separator comprising a dried product of the electric storage device slurry according to claim 2 or 4 on a substrate. 7 . An electrical storage device separator / electrode laminate comprising a dried product of the electrical storage device slurry according to claim 2 or 4 on an active material side of an electrode. 8 . An electric storage device comprising the electric storage device electrode according to claim 5 . 9 . An electric storage device comprising the electric storage device separator according to claim 6 . 10 . An electric storage device comprising the electric storage device separator / electrode laminate according to claim 7 .

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