Energy storage device binder aqueous solution, energy storage device slurry, energy storage device electrode, energy storage device separator, energy storage device separator / electrode laminate and energy storage device

Abstract

Provided is a power storage device binder aqueous solution comprising: a water-soluble polymer; a (meth)acrylamide; and a (meth)acrylonitrile, wherein the water-soluble polymer includes 0.01-1 mass% of a polymerization initiator unit, and the content of the (meth)acrylamide with respect to the water-soluble polymer is 0.01-1,000 mass ppm (exclusive of 1,000 mass ppm).

Description

Technical Field

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

Background Art

[0002] The applicant is considering a method of using a water-soluble polymer as a binder for a power storage device.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The problem to be solved by the present invention is to provide an aqueous solution of a power storage device binder for manufacturing a power storage device having excellent pencil hardness, breaking strength, initial Coulomb efficiency, and discharge capacity retention rate.

Means for Solving the Problems

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

[0006] The following items are provided by the present disclosure. (Item 1) An aqueous solution of a power storage device binder, wherein the aqueous solution of the power storage device binder contains a water-soluble polymer, (meth)acrylamide, and (meth)acrylonitrile, the water-soluble polymer contains 0.01% by mass to 1% by mass of polymerization initiator units, An aqueous solution of a battery storage device binder, wherein the content of (meth)acrylamide relative to the water-soluble polymer is 0.01 ppm by mass or more and less than 1000 ppm by mass. (Item 2) Energy storage device slurry, The energy 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 polymerization initiator units. A slurry for an energy storage device, wherein the content of (meth)acrylamide relative to the water-soluble polymer is 0.01 ppm by mass or more and less than 1000 ppm by mass. (Item 3) A slurry for an energy storage device as described above, containing an electrode active material. (Item 4) A slurry for energy storage devices as described above, containing non-conductive particles. (Item 5) An energy storage device electrode having a dried material of the energy storage device slurry described in any one of the above items on a current collector. (Item 6) A storage device separator having a dried product of the storage device slurry described in any one of the above items on a substrate. (Item 7) A storage device separator / electrode laminate having a dried material of the storage device slurry described in any one of the above items on the active material side of the electrode. (Item 8) A storage device including the energy storage device electrodes described in the above items. (Item 9) Energy storage devices, including the energy storage device separator described in the above items. (Item 10) Energy storage device including the energy storage device separator / electrode laminate described in the above items. (Item A1) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 1 mol% to 99.998 mol% of (meth)acrylamide units. (Item A2) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 10 mol% to 99.9 mol% of (meth)acrylamide units. (Item A3) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 20 mol% or more and less than 99.65 mol% of (meth)acrylamide units. (Item A4) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 55 mol% to 95 mol% of (meth)acrylamide units. (Item A5) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 1% to 99.998% by mass of (meth)acrylamide units. (Item A6) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 10% to 99.9% by mass of (meth)acrylamide units. (Item A7) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, containing 20% ​​by mass or more and less than 99.65% by mass of (meth)acrylamide units, or an aqueous solution of the energy storage device slurry described in the above item. (Item A8) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 55% to 95% by mass of (meth)acrylamide units. (Item A9) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 0 mol% to 80 mol% of N-substituted mono(meth)acrylamide units. (Item A10) The aforementioned water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 1 mol% to 70 mol% of N-substituted mono(meth)acrylamide units. (Item A11) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 0% to 80% by mass of N-substituted mono(meth)acrylamide units. (Item A12) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 1% to 70% by mass of N-substituted mono(meth)acrylamide units. (Item A13) The water-soluble polymer contains an N-monosubstituted mono(meth)acrylamide unit, and the N-monosubstituted mono(meth)acrylamide is represented by the following structural formula, wherein the product is an aqueous solution of the energy storage device binder described in the above item or an energy storage device slurry described in the above item. [ka] (R m1 represents a hydrogen atom or a methyl group. R m2 This represents a substituted or unsubstituted alkyl group or acetyl group. R m3 and R m4 Each of these independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, a hydroxyl group, an amino group, or an acetyl group. The amino group is -NR ma R mb It is represented as follows. R ma and R mb Each of these independently represents a hydrogen atom or a substituted or unsubstituted alkyl group. Examples of substituents on substituted alkyl groups include hydroxyl groups, amino groups, acetyl groups, and sulfonic acid groups. (Item A14) The N-monosubstituted mono(meth)acrylamide is one or more selected from the group consisting of monoalkyl(meth)acrylamide, N-methylol(meth)acrylamide, hydroxyethyl(meth)acrylamide, dimethylaminopropyl(meth)acrylamide, diacetone(meth)acrylamide, dimethylaminopropyl(meth)acrylamide methyl chloride quaternary salt, and dimethylaminoethyl(meth)acrylate benzyl chloride quaternary salt, the aqueous solution of the power storage device binder described in the above item or the power storage device slurry described in the above item. (Item A15) The water-soluble polymer contains N-disubstituted mono(meth)acrylamide units, and the N-disubstituted mono(meth)acrylamide is represented by the following structural formula, the aqueous solution of the power storage device binder described in the above item or the power storage device slurry described in the above item. [Chemical formula] (R d1 represents a hydrogen atom or a methyl group. R d2 and R d3 are each independently a substituted or unsubstituted alkyl group or an acetyl group, or R 2 and R 3 together represent a group forming a ring structure. R d4 and R d5 are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a hydroxy group, an amino group, or an acetyl group. The amino group is represented by -NR da R db as shown. R da and R db are each independently a hydrogen atom or a substituted or unsubstituted alkyl group. Examples of the substituent of the substituted alkyl group include a hydroxy group, an amino group, an acetyl group, a sulfonic acid group, etc.) (Item A16) The N-disubstituted mono(meth)acrylamide is one or more selected from the group consisting of N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N,N-dipropyl(meth)acrylamide, and (meth)acryloylmorpholin, wherein the energy storage device binder aqueous solution or energy storage device slurry described in the above item is an aqueous solution of the energy storage device binder described in the above item. (Item A17) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 0 mol% to 1.0 mol% of unsaturated hydrocarbon sulfonic acid and / or its salt units. (Item A18) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 0.001 mol% to 0.5 mol% of unsaturated hydrocarbon sulfonic acid and / or its salt units. (Item A19) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 0.001 mol% to 0.1 mol% of unsaturated hydrocarbon sulfonic acid and / or its salt units. (Item A20) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, containing 0% to 1.0% by mass of unsaturated hydrocarbon sulfonic acid and / or its salt units, or an aqueous solution of the energy storage device slurry described in the above item. (Item A21) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an aqueous solution of the energy storage device slurry described in the above item, containing 0.001% to 0.5% by mass of unsaturated hydrocarbon sulfonic acid and / or salt units thereof. (Item A22) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an aqueous solution of the energy storage device slurry described in the above item, containing 0.001% to 0.1% by mass of unsaturated hydrocarbon sulfonic acid and / or salt units thereof. (Item A23) The unsaturated hydrocarbon sulfonic acid or its salt is one or more selected from the group consisting of (meth)allyl sulfonic acid and (meth)allyl sulfonate sodium, wherein the aqueous solution of the energy storage device binder or the energy storage device slurry described in the above item. (Item A24) The water-soluble polymer is an aqueous solution of the energy storage device binder or the energy storage device slurry described in the above item, comprising 0 mol% to 70 mol% of an unsaturated carboxylic acid and / or its salt units. (Item A25) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 2 mol% to 40 mol% of an unsaturated carboxylic acid and / or its salt units. (Item A26) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, containing 0% to 70% by mass of unsaturated carboxylic acid and / or salt units thereof, or an aqueous solution of the energy storage device slurry described in the above item. (Item A27) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, containing 2% to 40% by mass of unsaturated carboxylic acid and / or salt units thereof, or an aqueous solution of the energy storage device slurry described in the above item. (Item A28) The aforementioned unsaturated carboxylic acid and / or salt thereof is one or more selected from the group consisting of (meth)acrylic acid, sodium (meth)acrylate, lithium (meth)acrylate, calcium (meth)acrylate, and ammonium (meth)acrylate, wherein the aqueous solution of the energy storage device binder or the energy storage device slurry described in the above item is as described in the above item. (Item A29) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 0 mol% to 50 mol% of α,β-unsaturated nitrile units. (Item A30) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 10 mol% to 40 mol% of α,β-unsaturated nitrile units. (Item A31) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 0% to 50% by mass of α,β-unsaturated nitrile units. (Item A32) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 10% to 40% by mass of α,β-unsaturated nitrile units. (Item A33) The α,β-unsaturated nitrile is (meth)acrylonitrile, in the aqueous solution of the energy storage device binder described in the above item or the energy storage device slurry described in the above item. (Item A34) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 0 mol% to 40 mol% of alkoxyalkyl (meth)acrylate units. (Item A34) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 0% to 60% by mass of alkoxyalkyl (meth)acrylate units. (Item A35) The alkoxyalkyl (meth)acrylate is 2-methoxyethyl (meth)acrylate, wherein the aqueous solution of the energy storage device binder or the energy storage device slurry described in the above item is an aqueous solution of the energy storage device binder described in the above item. (Item A36) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 0 mol% to 80 mol% of hydroxyl group-containing monomer units. (Item A37) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 5 mol% to 50 mol% of hydroxyl group-containing monomer units. (Item A38) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 20 mol% to 40 mol% of hydroxyl group-containing monomer units. (Item A39) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 0% to 85% by mass of hydroxyl group-containing monomer units. (Item A40) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 10% to 70% by mass of hydroxyl group-containing monomer units. (Item A41) The water-soluble polymer is an aqueous solution of the energy storage device binder described in the above item, or an energy storage device slurry described in the above item, containing 25% to 45% by mass of hydroxyl group-containing monomer units. (Item A42) The hydroxyl group-containing monomer is one or more selected from the group consisting of 2-hydroxyethyl (meth)acrylate and 2-hydroxyethyl vinyl ether, wherein the aqueous solution of the energy storage device binder or the energy storage device slurry described in the above item is described in the above item.

[0007] The one or more of the features described above may be provided in combinations other than those explicitly stated. [Effects of the Invention]

[0008] By using the aqueous binder solution for energy storage devices disclosed herein, it is possible to manufacture energy storage devices with superior pencil hardness, fracture strength, initial Coulomb efficiency, and discharge capacity retention rate. [Modes for carrying out the invention]

[0009] Throughout this disclosure, the ranges of numerical values ​​such as physical properties and content may be set as appropriate (for example, by selecting from the values ​​listed in each of the items below). Specifically, when the numerical value α is given as A3, A2, A1 (A3 > A2 > A1), the range of the numerical value α may include, for example, A3 or less, A2 or less, less than A3, less than A2, A1 or more, A2 or more, greater than A1, greater than A2, A1 to A2 (A1 or more and A2 or less), A1 to A3, A2 to A3, A1 or more and less than A3, A1 or more and less than A2, A2 or more and less than A3, greater than A1 and less than A3, greater than A1 and A3 or less, greater than A1 and A2 or less, greater than A2 and A3 or less.

[0010] The components, conditions, numerical values, etc., are not limited to those described in the specification, as long as the problems that this invention aims to solve are resolved.

[0011] "αβ amount (A / B)" means the amount of β (α) of A relative to 100 α% of B. α can be expressed as mass%, mole%, or parts by mass, for example. β amount can be expressed as content, amount used, for example.

[0012] "γ ratio (A / B)" refers to the γ ratio calculated using the formula "A ÷ B". Examples of γ ratios include mass ratios and molar ratios.

[0013] In this disclosure, "non-volatile content" means the total mass of components other than organic solvents and water. In one embodiment, the non-volatile content of object A is the total mass of components remaining when 1 g of object A is heated at 105°C and a constant weight is reached.

[0014] "(Meth)acrylic" means "at least one selected from the group consisting of acrylic and methacrylic." "(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 alkyl groups include linear alkyl groups, branched alkyl groups, and cycloalkyl groups.

[0016] Examples of linear alkyl groups include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, and n-decamethyl group.

[0017] A "branched alkyl group" refers to a group that does not have a cyclic structure, in which at least one hydrogen atom of a linear alkyl group is substituted by an alkyl group.

[0018] Examples of branched alkyl groups include i-propyl group, diethylpentyl group, trimethylbutyl group, trimethylpentyl group, and trimethylhexyl group.

[0019] Examples of cycloalkyl groups include monocyclic cycloalkyl groups, crosslinked ring cycloalkyl groups, and fused ring cycloalkyl groups. Furthermore, a group in which at least one hydrogen atom of a cycloalkyl group is substituted by an alkyl group is also considered a cycloalkyl group.

[0020] A "monocyclic ring" refers to a cyclic structure formed by covalent bonds between carbon atoms that does not have an internal bridging structure. A "condensed ring" refers to a cyclic structure in which two or more monocyclic rings share two atoms (i.e., each ring shares only one edge with the others through condensation). A "bridging ring" refers to a cyclic structure in which two or more monocyclic rings share three or more atoms.

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

[0022] Examples of crosslinked ring cycloalkyl groups include tricyclodecyl groups, adamantyl groups, norbornyl groups, and the like.

[0023] Alkyl groups also include combinations of linear alkyl groups, branched alkyl groups, and cycloalkyl groups. Examples of such combinations include cycloalkylalkyl groups.

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

[0025] An "inorganic salt" refers to a salt in which the cation part is a metal cation.

[0026] Examples of inorganic salts include sodium salts, lithium salts, and calcium salts.

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

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

[0029] <Water-soluble polymer: polymer> Water-soluble polymers can be used individually or in combination of two or more types.

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

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

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

[0033] Examples of mol% content ((meth)acrylamide units / water-soluble polymer) include 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 above content is preferably 1 mol% to 99.998 mol%, more preferably 10 mol% to 99.9 mol%, even more preferably 20 mol% or more and less than 99.65 mol%, and particularly preferably 55 mol% to 95 mol%. Reasons for preference include, for example, improved dispersibility and improved storage stability.

[0034] Examples of mass% content ((meth)acrylamide units / water-soluble polymer) include 99.998% by mass, 99.99% by mass, 95% by mass, 90% by mass, 85% by mass, 80% by mass, 75% by mass, 70% by mass, 65% by mass, 60% by mass, 55% by mass, 50% by mass, 45% by mass, 40% by mass, 35% by mass, 30% by mass, 25% by mass, 20% by mass, 15% by mass, 10% by mass, 9% by mass, 5% by mass, 4% by mass, 2% by mass, and 1% by mass. In one embodiment, the above content is preferably 1% by mass to 99.998% by mass, more preferably 10% by mass to 99.9% by mass, even more preferably 20% by mass or more and less than 99% by mass, and particularly preferably 55% by mass to 95% by mass. Reasons for preference 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 N-substituted mono(meth)acrylamide units. The N-substituted mono(meth)acrylamides 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 the nitrogen atom are replaced by a group other than hydrogen. [ka] (In the formula, R 1 (This is either a hydrogen atom or a methyl group.)

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

[0038] In one embodiment, the N-monosubstituted mono(meth)acrylamide is represented by the following structural formula. [ka] (R m1 represents a hydrogen atom or a methyl group. R m2 This represents a substituted or unsubstituted alkyl group or acetyl group. R m3 and R m4 Each of these independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, a hydroxyl group, an amino group, or an acetyl group. The amino group is -NR ma R mb It is represented as follows. R ma and R mb Each of these independently represents a hydrogen atom or a substituted or unsubstituted alkyl group. Examples of substituents on substituted alkyl groups include hydroxyl groups, amino groups, acetyl groups, and sulfonic acid groups.

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

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

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

[0042] In one embodiment, the N,N-disubstituted mono(meth)acrylamide is represented by the following structural formula. [ka] (R d1 represents a hydrogen atom or a methyl group. R d2 and R d3 Each of these is independently a substituted or unsubstituted alkyl group or acetyl group, or R 2 and R 3 These represent groups that combine to form a ring structure. R d4 and R d5 Each of these independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, a hydroxyl group, an amino group, or an acetyl group. The amino group is -NR da R db It is represented as follows. R da and R db Each of these independently represents a hydrogen atom or a substituted or unsubstituted alkyl group. Examples of substituents on substituted alkyl groups include hydroxyl groups, amino groups, acetyl groups, and sulfonic acid groups.

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

[0044] "Dialkyl(meth)acrylamide" refers to a compound in which two hydrogen atoms directly bonded to the nitrogen atom of (meth)acrylamide are replaced by an unsubstituted alkyl group.

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

[0046] The mol% content (N-substituted mono(meth)acrylamide units / water-soluble polymer) is, 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% Examples include 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 above content is preferably 0 mol% to 80 mol%, more preferably 1 mol% to 60 mol%, even more preferably 0.001 mol% or more and less than 5 mol%, and particularly preferably 0.001 to 1 mol%.

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

[0048] The molar content (N-monosubstituted mono(meth)acrylamide units / water-soluble polymer) is, 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% Examples include 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 above content is preferably 0 mol% to 80 mol%, more preferably 0 mol% to 20 mol%, even more preferably 0.001 mol% or more and less than 5 mol%, and particularly preferably 0.001 to 1 mol%.

[0049] The mass% content (N-monosubstituted mono(meth)acrylamide unit / water-soluble polymer) is, for example, 80% by mass, 75% by mass, 70% by mass, 65% by mass, 60% by mass, 55% by mass, 50% by mass, 45% by mass, 4 0 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 quality Examples include % by mass, 0.9% by mass, 0.7% by mass, 0.5% by mass, 0.45% by mass, 0.4% by mass, 0.35% by mass, 0.3% by mass, 0.25% by mass, 0.20% by mass, 0.15% by mass, 0.10% by mass, 0.08% by mass, 0.06% by mass, 0.05% by mass, 0.03% by mass, 0.01% by mass, 0.009% by mass, 0.007% by mass, 0.005% by mass, 0.003% by mass, 0.001% by mass, 0% by mass, etc. In one embodiment, the above content is preferably 0% by mass to 80% by mass, more preferably 0% by mass to 20% by mass, even more preferably 0.001% by mass or more and less than 5% by mass, and particularly preferably 0.001% by mass to 1% by mass.

[0050] The mol% content (N-disubstituted mono(meth)acrylamide units / water-soluble polymer) is, 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% Examples include 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 above content is preferably 0 mol% to 80 mol%, more preferably 0 mol% to 20 mol%, even more preferably 0.001 mol% or more and less than 5 mol%, and particularly preferably 0.001 to 1 mol%.

[0051] The mass% content (N-disubstituted mono(meth)acrylamide units / water-soluble polymer) is, for example, 80% by mass, 75% by mass, 70% by mass, 65% by mass, 60% by mass, 55% by mass, 50% by mass, 45% by mass, 4 0 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 quality Examples include % by mass, 0.9% by mass, 0.7% by mass, 0.5% by mass, 0.45% by mass, 0.4% by mass, 0.35% by mass, 0.3% by mass, 0.25% by mass, 0.20% by mass, 0.15% by mass, 0.10% by mass, 0.08% by mass, 0.06% by mass, 0.05% by mass, 0.03% by mass, 0.01% by mass, 0.009% by mass, 0.007% by mass, 0.005% by mass, 0.003% by mass, 0.001% by mass, 0% by mass, etc. In one embodiment, the above content is preferably 0% by mass to 80% by mass, more preferably 0% by mass to 20% by mass, even more preferably 0.001% by mass or more and less than 5% by mass, and particularly preferably 0.001% by mass to 1% by mass.

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

[0053] "Unsaturated hydrocarbon sulfonic acid" refers to sulfonic acid whose structure, aside from the sulfonic acid (salt) group, consists only of carbon and hydrogen atoms.

[0054] Examples of unsaturated hydrocarbon sulfonic acids or their salts include vinyl sulfonic acid, styrene sulfonic acid, (meth)allyl sulfonic acid, sodium vinyl sulfonate, sodium styrene sulfonate, and sodium (meth)allyl sulfonate.

[0055] Examples of mol% content (unsaturated hydrocarbon sulfonic acid and / or its salt units / water-soluble polymer) include 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 above content is preferably 0 mol% to 1.0 mol%, more preferably 0.001 mol% to 0.5 mol%, even more preferably 0.001 mol% to 0.1 mol%, and particularly preferably less than 0.01 mol%. The reasons for preference include, for example, improved pencil hardness and improved fracture strength.

[0056] The mass% content (unsaturated hydrocarbon sulfonic acid and / or its salt unit / water-soluble polymer) is, for example, 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% by mass, 0.3% by mass, 0.25% by mass, 0.20% by mass, 0.15% by mass, 0.10% by mass, 0.08% by mass, 0.06% by mass, 0.05% by mass, 0 Examples include .03% by mass, 0.01% by mass, 0.009% by mass, 0.007% by mass, 0.005% by mass, 0.003% by mass, 0.001% by mass, and 0% by mass. In one embodiment, the above content is preferably 0% to 1.0% by mass, more preferably 0.001% to 0.5% by mass, and even more preferably 0.001% to 0.1% by mass. The reasons for preference include, for example, improved pencil hardness and improved fracture strength.

[0057] The neutralization rate [unit amount of unsaturated hydrocarbon sulfonate / (unit amount of unsaturated hydrocarbon sulfonate + unit amount of unsaturated hydrocarbon sulfonic acid)] can be, 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] (Polyfunctional monomers) In one embodiment, the water-soluble polymer may optionally contain polyfunctional monomer units. The polyfunctional monomers may be used alone or in combination of two or more.

[0059] A "polyfunctional monomer" refers to a monomer that has two or more ethylenically unsaturated double bonds.

[0060] Examples of polyfunctional monomers include polyfunctional (meth)acrylamide compounds, tri(allyl group)-containing monomers, and tri((meth)acryloyl group)-containing triazines.

[0061] A "polyfunctional (meth)acrylamide compound" refers to a compound having two or more (meth)acrylamide groups. [ka] (In the formula, R 1 (This is either a hydrogen atom or a methyl group.)

[0062] Examples of polyfunctional (meth)acrylamide compounds 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-ethanediyloxy-3,1-propanediyl)]bis(meth)acrylamide, and N,N-1,2-ethanediylbis{N-[2-((meth)acryloylamino)ethyl](meth)acrylamide}.

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

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

[0065] Examples of molar content (polyfunctional monomer units / water-soluble polymer) include 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%, and 0 mol%. In one embodiment, the above content is preferably 0 to 10 mol%, and more preferably 0.05 to 2 mol%.

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

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

[0068] Examples of unsaturated carboxylic acids or their salts include (meth)acrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, sodium (meth)acrylate, sodium crotonic acid, sodium maleate, sodium fumarate, sodium itaconic acid, lithium (meth)acrylate, lithium crotonic acid, lithium maleate, lithium fumarate, lithium itaconic acid, calcium (meth)acrylate, calcium crotonic acid, calcium maleate, calcium fumarate, calcium itaconic acid, ammonium (meth)acrylate, ammonium crotonic acid, ammonium maleate, ammonium fumarate, ammonium itaconic acid, and the like.

[0069] Examples of mol% content (unsaturated carboxylic acid and / or its salt units / water-soluble polymer) include 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%, and 0 mol%. In one embodiment, the above content is preferably 0 mol% to 70 mol%, and more preferably 2 mol% to 40 mol%.

[0070] Examples of mass% content (unsaturated carboxylic acid and / or its salt units / water-soluble polymer) include 70% by mass, 65% by mass, 60% by mass, 55% by mass, 50% by mass, 45% by mass, 40% by mass, 35% by mass, 30% by mass, 29% by mass, 25% by mass, 20% by mass, 15% by mass, 10% by mass, 9% by mass, 5% by mass, 4% by mass, 2% by mass, 1% by mass, 0% by mass, etc. In one embodiment, the above content is preferably 0% by mass to 70% by mass, more preferably 0% by mass to 40% by mass, and even more preferably 2% by mass to 40% by mass.

[0071] The neutralization rate [amount of unsaturated carboxylate per unit / (amount of unsaturated carboxylate per unit + amount of unsaturated carboxylic acid per unit)] can be, 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 between 10% and 100%.

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

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

[0074] Examples of mol% content (α,β-unsaturated nitrile units / water-soluble polymer) include 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%, and 0 mol%. In one embodiment, the above content is preferably 0 mol% to 50 mol%, more preferably 0 mol% to 40 mol%, and even more preferably 10 mol% to 40 mol%.

[0075] Examples of mass% content (α,β-unsaturated nitrile units / water-soluble polymer) include 50% by mass, 45% by mass, 40% by mass, 35% by mass, 30% by mass, 25% by mass, 20% by mass, 15% by mass, 10% by mass, 9% by mass, 5% by mass, 4% by mass, 2% by mass, 1% by mass, and 0% by mass. In one embodiment, the above content is preferably 0% by mass to 50% by mass, more preferably 0% by mass to 30% by mass, and even more preferably 5% by mass to 30% by mass.

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

[0077] Examples of alkoxyalkyl (meth)acrylates 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 ( Examples include 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, butoxymethyl (meth)acrylate, etc.

[0078] Examples of molar content (alkoxyalkyl (meth)acrylate units / 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%, and 0 mol%. In one embodiment, the above content is preferably 0 mol% to 40 mol%.

[0079] Examples of mass% content (alkoxyalkyl (meth)acrylate units / water-soluble polymer) include 60% by mass, 55% by mass, 50% by mass, 45% by mass, 40% by mass, 35% by mass, 30% by mass, 25% by mass, 20% by mass, 15% by mass, 10% by mass, 9% by mass, 5% by mass, 4% by mass, 2% by mass, 1% by mass, and 0% by mass. In one embodiment, the above content is preferably 0% by mass to 60% by mass.

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

[0081] Examples of hydroxyl group-containing monomers include hydroxyl group-containing (meth)acrylic acid esters and hydroxyl group-containing vinyl ethers.

[0082] Examples of hydroxyl group-containing (meth)acrylic acid esters include hydroxyl group-containing linear (meth)acrylic acid esters and hydroxyl group-containing branched (meth)acrylic acid esters.

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

[0084] Examples of hydroxyl group-containing branched (meth)acrylic acid esters 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-methylpropyl (meth)acrylate, 2-hydroxy-1-methylpropyl (meth)acrylate, 3-hydroxy-1-methylpropyl (meth)acrylate, 1-ethyl-2-hydroxyethyl (meth)acrylate, 1-hydroxy-2-methylpropyl (meth)acrylate, 2-hydroxy-2-methylpropyl (meth)acrylate, 3-hydroxy-2-methylpropyl (meth)acrylate, and 1,1-dimethyl-2-hydroxyethyl (meth)acrylate.

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

[0086] Examples of hydroxyalkyl vinyl ethers include hydroxylinear alkyl vinyl ethers, hydroxybranched alkyl vinyl ethers, and hydroxycycloalkyl vinyl ethers.

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

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

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

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

[0091] Examples of polymethylene glycol monovinyl ethers 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, decamethylene glycol monovinyl ether, and the like.

[0092] Examples of polyethylene glycol monovinyl ethers 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, decaethylene glycol monovinyl ether, and the like.

[0093] Examples of polypropylene glycol monovinyl ethers 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, decapropylene glycol monovinyl ether, and the like.

[0094] Examples of molar content (hydroxyl group-containing monomer units / water-soluble polymer) include 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%, and 0 mol%. In one embodiment, the above content is preferably 0 mol% to 80 mol%, more preferably 5 mol% to 50 mol%, and even more preferably 20 mol% to 40 mol%.

[0095] Examples of mass% content (hydroxyl group-containing monomer units / water-soluble polymer) include 85% by mass, 80% by mass, 75% by mass, 70% by mass, 65% by mass, 60% by mass, 55% by mass, 50% by mass, 45% by mass, 40% by mass, 35% by mass, 30% by mass, 25% by mass, 20% by mass, 15% by mass, 10% by mass, 9% by mass, 5% by mass, 4% by mass, 2% by mass, 1% by mass, and 0% by mass. In one embodiment, the above content is preferably 0% by mass to 85% by mass, more preferably 10% by mass to 70% by mass, and even more preferably 25% by mass to 45% by mass.

[0096] (Polymerization initiator) Polymerization initiators can be used alone or in combination of two or more.

[0097] Polymerization initiators include, for example, azo-based initiators.

[0098] Examples of azo initiators include 2,2'-azobis-2-amidinopropane dihydrochloride.

[0099] Examples of mol% content (polymerization initiator units / water-soluble polymer) include 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 above content is preferably 0.01 mol% to 1 mol%.

[0100] Examples of mass% content (polymerization initiator units / water-soluble polymer) include 1% by mass, 0.95% by mass, 0.9% by mass, 0.85% by mass, 0.8% by mass, 0.75% by mass, 0.7% by mass, 0.65% by mass, 0.6% by mass, 0.55% by mass, 0.5% by mass, 0.45% by mass, 0.4% by mass, 0.35% by mass, 0.3% by mass, 0.25% by mass, 0.2% by mass, 0.15% by mass, 0.1% by mass, 0.07% by mass, 0.05% by mass, 0.03% by mass, 0.01% by mass, and so on. In one embodiment, the above content is preferably 0.01% by mass to 1% by mass.

[0101] (Monomers other than those listed above: Other components) The above water-soluble polymer may optionally contain monomer units (other components) that are not (meth)acrylamide, N-substituted mono(meth)acrylamide, unsaturated hydrocarbon sulfonic acid and / or salts thereof, polyfunctional monomer, unsaturated carboxylic acid and / or salts thereof, α,β-unsaturated nitrile, alkoxyalkyl (meth)acrylate, or hydroxyl group-containing monomer. The other components may be used alone or in combination of two or more.

[0102] Other components include, for example, unsaturated phosphoric acid and / or its salts, alkyl (meth)acrylic acid esters, conjugated dienes, aromatic vinyl compounds, and the like.

[0103] Examples of unsaturated phosphoric acids 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 alkyl (meth)acrylic acid esters include linear alkyl (meth)acrylic acid esters, branched alkyl (meth)acrylic acid esters, and alicyclic alkyl (meth)acrylic acid esters.

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

[0106] Examples of branched alkyl (meth)acrylate esters include i-propyl (meth)acrylate, i-butyl (meth)acrylate, i-amyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate.

[0107] Examples of alicyclic alkyl (meth)acrylic acid esters include cyclohexyl (meth)acrylate.

[0108] Examples of conjugated dienes include 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 2-chlor-1,3-butadiene, substituted linear-conjugated pentadiene, and substituted and side-conjugated hexadiene.

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

[0110] Examples of mass % content (other component units / water-soluble polymer) include less than 10% by mass, less than 9% by mass, less than 7% by mass, less than 5% by mass, less than 4% by mass, less than 2% by mass, less than 1% by mass, less than 0.9% by mass, less than 0.7% by mass, less than 0.5% by mass, less than 0.4% by mass, less than 0.2% by mass, less than 0.1% by mass, and 0% by mass. In one embodiment, the above content is preferably less than 10% by mass, more preferably less than 5% by mass, even more preferably less than 1% by mass, and particularly preferably 0% by mass.

[0111] The mol% content (other component units / water-soluble polymer) can be, 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 above content is preferably less than 10 mol%, more preferably less than 5 mol%, even more preferably less than 1 mol%, and particularly preferably 0 mol%.

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

[0113] (Pre-polymerization step) The "pre-polymerization process" refers to the process of manufacturing (polymerizing) water-soluble polymers.

[0114] Examples of mass% usage amounts (radical polymerization initiator / monomer group) in the prepolymerization step include 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%, and 0.05 mass%. In one embodiment, the above usage amount in the prepolymerization step is preferably 0.05 mass% to 1.0 mass%.

[0115] Examples of prepolymerization temperatures 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 prepolymerization times 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, and more preferably 2 to 10 hours.

[0117] (Post-polymerization step) The "post-polymerization step" refers to the step after the pre-polymerization step in which a polymerization initiator is added and the reaction is carried out further.

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

[0119] In the post-polymerization step, the mass% usage amount (radical polymerization initiator / monomer group) can be, 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 above usage amount is preferably 0.05 mass% to 1.0 mass%.

[0120] Examples of post-polymerization temperatures 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 post-polymerization times 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, and more preferably 2 to 10 hours.

[0122] In one embodiment, persulfates and redox polymerization initiators may be used as radical polymerization initiators in either the post-polymerization step or the pre-polymerization step.

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

[0124] Examples of redox polymerization initiators include combination systems (persulfate and reducing agent).

[0125] Examples of reducing agents include sodium bisulfite.

[0126] <Physical properties (water-soluble polymers), etc.> Examples of weight-average molecular weight (water-soluble polymer: Mw) include 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, and 100,000. In one embodiment, the above weight-average molecular weight (Mw) is preferably between 100,000 and 6 million, and more preferably between 350,000 and 6 million.

[0127] Examples of number-average molecular weights (water-soluble polymers: Mn) include 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, and 10,000. In one embodiment, the above number-average molecular weight (Mn) is preferably 10,000 or more.

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

[0129] The measurement conditions (weight-average molecular weight, number-average molecular weight) are as follows: • Measuring instrument: GPC (model number: HLC-8420) manufactured by Tosoh Corporation • Columns: TSKgel Guardcolum PWXL, TSK-GEL G4000, TSK-GEL α-M (all manufactured by Tosoh Corporation) • Eluent: 0.2M NaNO3 50mM phosphate buffer / acetonitrile = 90 / 10 (v / v) aqueous solution Column temperature: 40°C • Calibration curve: Standard polyethylene oxide - polyethylene glycol • Measured concentration: 0.10% by mass (concentration of water-soluble polymer) • Filter: Cellulose acetate cartridge filter (manufactured by Tosoh Corporation, MyShori Disc W-13-2, pore size 0.2 μm)

[0130] The mass part content ((meth)acrylamide / water-soluble polymer) is, for example, 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 Examples include 250 ppm by mass, 200 ppm by mass, 150 ppm by mass, 100 ppm by mass, 50 ppm by mass, 25 ppm by mass, 10 ppm by mass, 5 ppm by mass, 1 ppm by mass, 0.9 ppm by mass, 0.7 ppm by mass, 0.5 ppm by mass, 0.3 ppm by mass, 0.1 ppm by mass, 0.09 ppm by mass, 0.07 ppm by mass, 0.05 ppm by mass, 0.03 ppm by mass, 0.01 ppm by mass, and so on. In one embodiment, the above content is preferably 0.01 ppm by mass or more and less than 1000 ppm by mass.

[0131] The mass part content ((meth)acrylonitrile / water-soluble polymer) is, for example, 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, 2 Examples include 50 ppm by mass, 200 ppm by mass, 150 ppm by mass, 100 ppm by mass, 50 ppm by mass, 25 ppm by mass, 10 ppm by mass, 5 ppm by mass, 1 ppm by mass, 0.9 ppm by mass, 0.7 ppm by mass, 0.5 ppm by mass, 0.3 ppm by mass, 0.1 ppm by mass, 0.09 ppm by mass, 0.07 ppm by mass, 0.05 ppm by mass, 0.03 ppm by mass, 0.01 ppm by mass, 0 ppm by mass, etc. In one embodiment, the above content is preferably 0 ppm by mass or more and less than 1000 ppm by mass.

[0132] The mass part content (monomer / water-soluble polymer) 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, 1 500 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, 999 mass ppm, 950 mass ppm, 900 mass ppm, 850 quality Quantity 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, Examples include 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. In one embodiment, the above content is preferably 0.01 ppm by mass or more and less than 1000 ppm by mass, and more preferably 0.01 ppm by mass or more and less than 100 ppm by mass.

[0133] The monomer content can be measured under the following conditions. (1) Preparation (standard solution) Monomers ((meth)acrylamide, (meth)acrylonitrile) are collected in 20 mL screw tubes and diluted with ultrapure water to prepare standard aqueous solutions at concentrations of 2000 ppm, 1000 ppm, 500 ppm, 100 ppm, 10 ppm, 1 ppm, and 0.5 ppm. (2) (meth)acrylamide calibration curve Using a standard solution, perform measurements under the following conditions and create a calibration curve. Measuring equipment: HPLC (Agilent 1260 Infinity2 PrimeLC) Column: InertSustain AQ-C18 Column oven temperature: 40℃ Eluent: Phosphate buffer (sodium dihydrogen phosphate / ultrapure water = 8 / 1000 (v / v) aqueous solution) Measured concentration: 0.20% by mass (concentration of water-soluble polymer) Injection volume: 4μL (3) (Meth)acrylonitrile calibration curve Using a standard solution, perform measurements under the following conditions and create a calibration curve. Measuring equipment: GC (Agilent 7890B)-MS (Agilent 5977A) Column: InertCap AQUATIC-2 Carrier gas: Helium Measured concentration: 1% by mass (concentration of water-soluble polymer) Measurement conditions: 50°C (2 min.) → 230°C (5 min. / min.) Injection volume: 1000μL (4) Preparation (sample) Dilute each sample 50 times using a screw-cap tube. Measure under the above conditions and determine the monomer content in the sample from the calibration curve.

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

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

[0136] The sulfur content can be measured under the following conditions. The measurement is performed using an X-ray fluorescence analyzer (ZSX PrimusIV, manufactured by Rigaku Corporation). The content is calculated using the oxide equivalent value. <Measurement conditions> Measurement atmosphere: Helium Sample form: Liquid Measurement range: F~U Measurement diameter: 30mm Measurement time: Standard Pre-measurement preparation: Place the liquid sample in a container and cover it with polypropylene (PP) film. Quantitative method: Semi-quantitative analysis using fundamental parameter method If the X-ray fluorescence analyzer shows no detection (0 ppm), the sample is measured using combustion ion chromatography (AQF-2100H, manufactured by Nitto Seiko Analytic Co., Ltd.). <Measurement conditions> • Separation column: Product name 'IonPac AS12A', manufactured by DIONEX (inner diameter 4mm, length 200mm) • Guard column: Product name 'IonPac AG12A', manufactured by DIONEX (inner diameter 4mm, length 50mm) • Pre-measurement processing: None • Quantitative method: Quantitative determination using a calibration curve with a standard sample (Na2SO4). • Solid weight of the sample to be burned: 50 mg • Amount of absorbent liquid used to absorb gas generated after combustion: 10 mL • Internal standard sample concentration of the absorption solution (sodium tartrate dihydrate): 10 ppm (tartrate ion concentration) • Hydrogen peroxide concentration in the absorption solution (aqueous solution of hydrogen peroxide): 90 ppm • Eluent: 2.7 mmol / L sodium carbonate + 0.3 mmol / L sodium bicarbonate aqueous solution • The absorbent solution is prepared by diluting it with ultrapure water.

[0137] Examples of type B viscosity (aqueous solution of energy storage device binder) 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, 9,000 mPa·s, 8,000 mPa·s, 7,000 mPa·s, 6,000 mPa·s, 5,000 mPa·s, 4,000 mPa·s, 3,000 mPa·s, 2,000 mPa·s, and 1,000 mPa·s. In one embodiment, the above type B viscosity is preferably between 1,000 mPa·s and 100,000 mPa·s.

[0138] The measurement conditions (Type B viscosity) are as follows: Non-volatile content concentration: 15% by mass Measurement temperature: 25℃ Type B Viscometer: Manufactured by Toki Sangyo Co., Ltd. Product name: "Type B Viscometer Model TVB-10" Viscosity 100-10000 mPa·s: No.3 rotor, rotation speed 12 rpm Viscosity over 10,000 mPa·s, 20,000 mPa·s: No. 3 rotor, rotation speed 6 rpm Viscosity over 20,000 mPa·s (100,000 mPa·s): No. 4 rotor, rotation speed 6 rpm

[0139] Examples of glass transition temperatures (for water-soluble polymers) include 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, and 0°C. In one embodiment, the glass transition temperature is preferably 0°C or higher, and more preferably 30°C or higher.

[0140] Based on the glass transition temperature (homopolymer) and mass fraction (monomer), the glass transition temperature (water-soluble polymer) can be calculated using Fox's formula. 1 / Tg=(W1 / Tg1)+(W2 / Tg2)+(W3 / Tg3)+···+(W n / Tg n ) [In Fox's formula, Tg is the glass transition temperature (K) of the polymer being sought, W1~W n These are the mass fractions of each monomer, Tg1~Tg n This indicates the glass transition temperature (homopolymer) (K) of each monomer.

[0141] The glass transition temperature can be measured using methods such as DSC (Differential Scanning Calorimetry), DTA (Differential Thermal Analysis), and TMA (Thermomechanical Analysis). The following are possible measurement conditions (glass transition temperature). Temperature range: -100℃ to 300℃ Heating rate: 10℃ / min

[0142] The glass transition temperature (for homopolymers) may also be based on values ​​found in the literature. Examples of such literature include "Chemical Handbook, Basic Edition II, edited by the Chemical Society of Japan (5th revised edition)," p. 325. Examples of glass transition temperatures (for homopolymers) include the following temperatures. Acrylamide: 165℃ Acrylic acid: 106℃ Hydroxyethyl acrylate: -15℃ Acrylonitrile: 105℃

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

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

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

[0146] Examples of mass ratios (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, 0.05, etc. In one embodiment, the above mass ratio is preferably 0.05 to 0.33.

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

[0148] Examples of polyalkoxysilanes include trialkoxysilanes and tetraalkoxysilanes.

[0149] In one embodiment, the trialkoxysilane is represented by the following formula. [ka] (In the formula, R s1 R represents a substituted or unsubstituted alkyl group or alkenyl group. s2 ~R s4 Each of these independently represents an alkyl group.

[0150] A "substituted alkyl group" refers to an alkyl group in which the hydrogen atoms constituting the alkyl group are replaced by groups other than hydrogen atoms or alkyl groups.

[0151] Examples of substituents include amino groups, mercapto groups, isocyanate groups, and (meth)acryloyloxy groups.

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

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

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

[0155] Examples of isocyanate group-containing trialkoxysilanes include 3-isocyanatetopropyltriethoxysilane.

[0156] Examples of trialksoxysilanes containing a (meth)acryloyloxy group include 3-(meth)acryloxypropyltrimethoxysilane and 3-(meth)acryloxypropyltriethoxysilane.

[0157] Examples of alkenyl groups include vinyl groups and allyl groups.

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

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

[0160] "Partial hydrolyzed condensate of polyalkoxysilane" refers to a hydrolyzed condensate that contains an alkoxy group. From the perspective of not gelling, the term "partial hydrolyzed condensate of polyalkoxysilane" is used instead of "complete hydrolyzed condensate of polyalkoxysilane."

[0161] Examples of condensation degrees (hydrolyzed partial condensates) 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, and 1.01. In one embodiment, the above condensation degrees are preferably 1.01 to 1000, and more preferably 1.01 to 100.

[0162] Examples of weight-average molecular weights (hydrolyzed partial condensates) include 190,000, 170,000, 150,000, 130,000, 100,000, 90,000, 70,000, 50,000, 30,000, 20,000, 10,000, 9,000, 7,500, 5,000, 2,500, 1,000, 900, 750, 500, 250, 200, 175, 160, 150, 125, 110, and 100. In one embodiment, the above weight-average molecular weight is preferably between 100 and 190,000.

[0163] A partially condensed hydrolyzed polyalkoxysilane can be produced by hydrolyzing 100 parts by mass of polyalkoxysilane in the presence of 0 to 5 parts by mass of an acid catalyst or a base catalyst (preferably an acid catalyst) at a reaction temperature of 30°C to 60°C for 0.5 to 5.0 hours, thereby partially condensing it.

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

[0165] Examples of base catalysts include sodium hydroxide, lithium hydroxide, potassium hydroxide, calcium hydroxide, and amine compounds.

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

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

[0168] Other binders include, for example, diene copolymers, fluorine copolymers, amide-imide copolymers, and copolymers other than those mentioned above.

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

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

[0171] Examples of amide-imide copolymers include polyamides (PA), polyimides (PI), polyamide-imides (PAI), and aromatic polyamides.

[0172] Other copolymers include, for example, 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 salts thereof.

[0173] Examples of parts by mass content (other binders / water-soluble polymers) include 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 above content is preferably 0 to 100 parts by mass.

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

[0175] Dispersions (emulsions) include, for example, 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 emulsion, vinyl acetate-ethylene copolymer emulsion, polyethylene emulsion, and carboxymodified styrene. Examples include butadiene copolymer resin emulsion, 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] Examples of the parts by mass content (dispersion (emulsion) / water-soluble polymer) include 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 above content is preferably 0 to 100 parts by mass.

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

[0178] Examples of thickeners include cellulose polymers and / or salts thereof, polyvinyl alcohols, (modified) poly(meth)acrylic acid and / or salts thereof, polyethylene glycol, polyethylene oxide, polyvinylpyrrolidone, starch oxide, starch phosphate, casein, modified starch, and acrylonitrile-butadiene copolymer hydrogenates.

[0179] Examples of cellulose-based polymers and / or salts thereof include carboxymethylcellulose, methylcellulose, hydroxypropylcellulose, and the like.

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

[0181] Examples of the parts by mass content (thickener / water-soluble polymer) include 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 above content is preferably 0 to 100 parts by mass.

[0182] <Additives> The aqueous solution of the energy storage device binder may optionally contain, as additives, water-soluble polymers, water, hydrolyzed partial condensates of polyalkoxysilanes, and other agents that do not fall under the categories of binders, dispersions (emulsions), or thickeners. The additives may be used individually or in combination of two or more.

[0183] Examples of additives include dispersants, leveling agents, and antioxidants.

[0184] Examples of dispersants include anionic dispersants, cationic dispersants, nonionic dispersants, and polymeric dispersants.

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

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

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

[0188] The "polymer-type phenol compound" means a polymer having a phenol structure. The weight average molecular weight (polymer-type phenol compound) is preferably 200 to 1000, more preferably 600 to 700.

[0189] Examples of the parts by mass 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, 0 parts by mass, and the like.

[0190] Examples of the mass% content (additive / aqueous solution of the power storage device binder) 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%, 0 mass%, and the like.

[0191] Examples of the pH (aqueous solution of the power storage device binder) 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, 5, and the like. In one embodiment, the pH is preferably 5 to 9, more preferably 5 to 7.

[0192] The following conditions can be used for measurement (pH). Measuring instrument: Manufactured by Horiba, Ltd. Product name: "pH meter D-52" Measurement temperature: 25℃

[0193] Applications (aqueous binder solutions for energy storage devices) include, for example, aqueous binder solutions for energy storage device electrodes, aqueous binder solutions for batteries, aqueous binder solutions for non-aqueous secondary batteries, aqueous binder solutions for lithium-ion batteries, aqueous binder solutions for sodium-ion batteries, aqueous binder solutions for negative electrodes of energy storage devices, aqueous binder solutions for negative electrodes of batteries, aqueous binder solutions for negative electrodes of non-aqueous secondary batteries, aqueous binder solutions for lithium-ion batteries, aqueous binder solutions for negative electrodes of sodium-ion batteries, aqueous binder solutions for positive electrodes of energy storage devices, aqueous binder solutions for positive electrodes of batteries, aqueous binder solutions for positive electrodes of non-aqueous secondary batteries, aqueous binder solutions for positive electrodes of lithium-ion batteries, aqueous binder solutions for positive electrodes of sodium-ion batteries, aqueous binder solutions for separators of energy storage devices, aqueous binder solutions for separators of batteries, aqueous binder solutions for separators of non-aqueous secondary batteries, aqueous binder solutions for lithium-ion batteries, aqueous binder solutions for separators of sodium-ion batteries, and so on.

[0194] [Energy storage device slurry: Slurry] This disclosure relates to an energy storage device slurry, The energy 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 polymerization initiator units. The present invention relates to an energy storage device slurry in which the content of (meth)acrylamide in the water-soluble polymer is 0.01 ppm by mass or more and less than 1000 ppm by mass.

[0195] In this disclosure, “slurry” means a suspension of liquid and solid particles.

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

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

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

[0199] Examples of mass% content (hydrolyzed partial condensate / slurry) include 5% by mass, 4.5% by mass, 4% by mass, 3.5% by mass, 3% by mass, 2.5% by mass, 2% by mass, 1.5% by mass, 1% by mass, 0.9% by mass, 0.5% by mass, 0.1% by mass, 0.09% by mass, 0.05% by mass, 0.03% by mass, 0.01% by mass, etc. In one embodiment, the above content is preferably 0.01% by mass to 5% by mass.

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

[0201] The content (polymerization initiator units), content ((meth)acrylamide), content ((meth)acrylonitrile), content (monomers), content (other binders), content (dispersion (emulsion)), and content (thickeners) are examples of the above-mentioned content.

[0202] <Electrode active material> In one embodiment, the energy storage device slurry includes 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 types.

[0203] (Negative electrode active material) Examples of negative electrode active materials include carbon materials, materials that alloy with lithium, silicon materials, and lithium atom-containing oxides.

[0204] Examples of carbon materials include graphite, low-crystalline carbon, carbon black, fullerenes, carbon nanotubes, carbon nanofibers, carbon nanohorns, carbon fibrils, mesocarbon microbeads (MCMBs), pitch-based carbon fibers, and activated carbon.

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

[0206] Low-crystalline carbon includes, for example, soft carbon, hard carbon, etc.

[0207] Carbon black includes, for example, Ketjen black, acetylene black, channel black, lamp black, oil furnace black, thermal black, etc.

[0208] Materials that alloy with lithium include, for example, lead compounds, tin compounds, arsenic compounds, antimony compounds, aluminum compounds, etc.

[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 includes silicon oxide represented by the composition formula SiO z (0 < z ≤ 2, preferably 0.1 ≤ z ≤ 1).

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

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

[0213] The shape of the silicon material includes, for example, single crystal, polycrystal, amorphous, etc.

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

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

[0216] Examples of conductive polymers include polyacene.

[0217] A composite metal oxide can be represented, for example, by the following general formula. A α B β O γ (A represents an alkali metal or transition metal. B represents at least one selected from transition metals such as cobalt, nickel, aluminum, tin, and manganese. 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, respectively.)

[0218] Carbon materials exhibit small volume changes associated with the intercalation and deintercalation of lithium. Therefore, when using silicon materials as electrode active materials, it is preferable to use them in combination with carbon materials.

[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 lithium atom-containing oxides include lithium-transition metal composite oxides, lithium-transition metal phosphate compounds, and lithium-transition metal sulfate compounds.

[0221] Examples of lithium-transition metal composite oxides 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, the mass% content (carbon material and / or material alloyed with lithium / negative electrode active material) can be, for example, 100% by mass, 95% by mass, 90% by mass, 85% by mass, 80% by mass, 75% by mass, 70% by mass, 65% by mass, 60% by mass, 55% by mass, 50% by mass, 45% by mass, 40% by mass, 35% by mass, 30% by mass, 25% by mass, 20% by mass, 15% by mass, 10% by mass, 5% by mass, 0% by mass, etc. In one embodiment, the above content can be preferably 50% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, and particularly preferably 100% by mass.

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

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

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

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

[0227] Inorganic active materials can be partially elementally substituted. By including a carbon source material during reduction firing, inorganic active materials can be used as electrode active materials covered with carbon materials.

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

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

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

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

[0232] In this disclosure, "particle diameter" means the maximum distance between any two points on the contour line of a particle. "Average particle diameter" means a value calculated as the average value of particle diameters of particles observed within several to tens of fields of view using observation means such as a scanning electron microscope (SEM) or a transmission electron microscope (TEM).

[0233] The amounts of parts by mass of the water-soluble polymer / electrode active material include 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, and the like. In one embodiment, the above amounts are preferably 0.5 to 15 parts by mass.

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

[0235] Examples of conductive additives include fibrous carbon, carbon black, and fine metal powders.

[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, and furnace black.

[0238] Examples of metal fine powders 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 mass content (conductive additive / electrode active material) is preferably 0 to 10 parts by mass, and more preferably 0 to 6 parts by mass.

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

[0242] Examples of non-conductive particles include oxide particles, hydroxide particles, nitride particles, covalent crystalline particles, poorly soluble ionic crystalline particles, clay microparticles, aluminum particles, barium particles, calcium particles, and the like.

[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 (titania), BaTiO3, ZrO, and alumina-silica composite oxides.

[0244] Examples of 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 crystalline particles include silicon and diamond.

[0247] Examples of sparingly soluble ionic crystal particles include barium sulfate, calcium fluoride, and barium fluoride.

[0248] Examples of clay microparticles include silica, talc, montmorillonite, and other clay microparticles.

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

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

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

[0252] In one embodiment, the non-conductive particles are preferably boehmite, alumina, magnesium oxide, and barium sulfate.

[0253] Examples of average particle diameters (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, 0.01 μm, etc. In one embodiment, the above average particle diameter is preferably 0.01 μm to 30 μm.

[0254] Examples of mass% content (non-conductive particles / slurry) include 99.9% by mass, 95% by mass, 90% by mass, 80% by mass, 70% by mass, 60% by mass, 50% by mass, 40% by mass, 30% by mass, 20% by mass, 10% by mass, 5% by mass, 1% by mass, 0.5% by mass, 0.2% by mass, 0.1% by mass, etc. In one embodiment, the above content is preferably 0.1% by mass to 99.9% by mass.

[0255] Examples of the parts by mass content (water-soluble polymer / non-conductive particles) include 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, and so on. In one embodiment, the above 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> Slurry viscosity adjusting solvents can be used alone or in combination of two or more.

[0257] Examples of slurry viscosity adjusting solvents 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 amide solvents include N-methylpyrrolidone, dimethylformamide, and N,N-dimethylacetamide.

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

[0260] Examples of alcoholic solvents include methanol, ethanol, 2-propanol, isopropyl alcohol, 2-ethyl-1-hexanol, 1-nonanol, and lauryl alcohol.

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

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

[0263] Examples of ester solvents include benzyl acetate, isopentyl butyrate, methyl lactate, ethyl lactate, and butyl lactate.

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

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

[0266] Examples of sulfoxide and sulfone solvents include dimethyl sulfoxide and sulfolane.

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

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

[0269] <Additives> The above slurry may optionally contain additives that do not fall under any of the following categories: water-soluble polymers, water, other binders, dispersions (emulsions), thickeners, electrode active materials, non-conductive particles, or slurry viscosity adjusting solvents. Examples of additives include the agents mentioned above.

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

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

[0272] The above slurry can be manufactured by mixing a water-soluble polymer, water, an electrode active material or non-conductive particles, and optionally a hydrolyzed partial condensate of polyalkoxysilane, other binders, dispersions (emulsions), thickeners, slurry viscosity adjusting solvents, and additives.

[0273] Mixing means (slurry) include, for example, ball mills, sand mills, pigment dispersers, grinders, ultrasonic dispersers, homogenizers, planetary mixers, Hobart mixers, and the like.

[0274] Applications (energy storage device slurry) include, for example, energy storage device electrode slurry, battery electrode slurry, non-aqueous secondary battery electrode slurry, lithium-ion battery electrode slurry, sodium-ion battery electrode slurry, energy 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, energy 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, energy storage device separator slurry, battery separator slurry, non-aqueous secondary battery separator slurry, lithium-ion battery separator slurry, sodium-ion battery separator slurry, etc.

[0275] [Energy storage device electrodes: electrodes] This disclosure relates to an electrode for an energy storage device having a dried material of the above-mentioned energy storage device slurry on a current collector.

[0276] The energy storage device electrode is obtained by applying the above-mentioned energy storage device slurry to a current collector and drying it.

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

[0278] Examples of metallic materials include copper, iron, aluminum, nickel, stainless steel, and nickel-plated steel.

[0279] Examples of metallic materials include metal foil, metal cylinders, metal coils, and metal plates.

[0280] Examples of carbon materials include carbon cloth and carbon paper.

[0281] Examples of forms (carbon materials) include carbon plates, carbon thin films, and carbon cylinders.

[0282] Coating methods include, for example, comma coaters, gravure coaters, microgravure coaters, die coaters, bar coaters, and the like.

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

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

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

[0286] Applications (electrodes for energy storage devices) include, for example, positive electrodes for energy storage devices, negative electrodes for energy storage devices, battery electrodes, positive electrodes for batteries, negative electrodes for batteries, electrodes for non-aqueous secondary batteries, positive electrodes for non-aqueous secondary batteries, negative electrodes for non-aqueous secondary batteries, electrodes for lithium-ion batteries, positive electrodes for lithium-ion batteries, negative electrodes for lithium-ion batteries, electrodes for sodium-ion batteries, positive electrodes for sodium-ion batteries, negative electrodes for sodium-ion batteries, and so on.

[0287] [Energy Storage Device Separator: Separator] This disclosure relates to an energy storage device separator having a dried material of the above-mentioned energy storage device slurry on a substrate.

[0288] The above-mentioned energy storage device separator can be manufactured by applying the energy storage device separator slurry to one or both sides of a substrate and drying it.

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

[0290] (Porous polyolefin resin substrate) "Porous polyolefin resin substrate" means a microporous membrane containing 30% by mass or more of a resin such as polyolefins and mixtures or copolymers thereof.

[0291] Polyolefin resins can be used alone or in combination of two or more types. Examples of polyolefin resins include homopolymers and copolymers of ethylene, propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, etc.

[0292] Examples of three-dimensional structures (polyolefins) include isotactic, syndiotactic, and atactic structures.

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

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

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

[0296] Porous polyolefin resin substrates may be surface-treated as needed.

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

[0298] In one embodiment, the surface treatment is preferably a coating treatment with a polymer containing polar groups. This coating treatment can improve electrolyte impregnation and adhesion to the slurry dry product. Examples of polar groups include carboxylic acid groups, hydroxyl groups, sulfonic acid groups, and the like.

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

[0300] (Plastic nonwoven fabric) Examples of plastic nonwoven fabrics include nonwoven fabrics composed solely of 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, phenolic 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, polyazomethine resins, polyesteramide resins, polyetheretherketone resins, poly-p-phenylenebenzobisoxazole resins, polybenzimidazole resins, and ethylene-vinyl alcohol copolymer resins.

[0302] Examples of polyolefin resins include polypropylene, polyethylene, polymethylpentene, ethylene-vinyl alcohol copolymers, and olefin copolymers.

[0303] Examples of polyester resins include polyethylene terephthalate (PET) resins, polybutylene terephthalate (PBT) resins, polytrimethylene terephthalate (PPT) resins, polyethylene naphthalate (PEN) resins, polybutylene naphthalate resins, polyethylene isonaphthalate resins, and fully aromatic polyester resins.

[0304] Examples of acrylonitrile resins include polyacrylonitrile, copolymers of acrylonitrile and (meth)acrylic acid derivatives, vinyl acetate, etc.

[0305] Examples of polyamide resins include aliphatic polyamides, fully aromatic polyamides, and semi-aromatic polyamides.

[0306] Examples of aliphatic polyamides include nylon.

[0307] Examples of fully aromatic polyamides include poly-p-phenylene terephthalamide, poly-p-phenylene terephthalamide-3,4-diphenyl ether terephthalamide, and poly-m-phenylene isophthalamide.

[0308] "Semi-aromatic polyamide" refers to a polyimide in which part of the main chain of an aromatic polyamide is a fatty acid chain.

[0309] Plastic nonwoven fabric fibers may optionally include fibers other than synthetic resin fibers.

[0310] Other fibers besides synthetic resin fibers include, for example, solvent-spun cellulose, solvent-spun cellulose fibrils, regenerated cellulose, regenerated cellulose fibrils, natural cellulose fibers, natural cellulose fiber pulps, natural cellulose fiber fibrils, and inorganic fibers.

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

[0312] Examples of forms include single fibers and composite fibers.

[0313] "Single fiber" refers to a fiber made of a single resin. "Composite fiber" refers to a fiber made of two or more types of resins.

[0314] Examples of morphologies (composite fibers) include core-sheath type, eccentric type, side-by-side type, sea-island type, orange type, and multi-bimetal type.

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

[0316] "Average fiber diameter" refers to the average fiber diameter of 20 fibers randomly selected from scanning electron microscope images.

[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] "Pore diameter" refers to the width of the gap between fibers. "Average pore diameter" refers to the average value of the pore diameters of 20 fibers randomly selected from scanning electron microscope images.

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

[0320] <Manufacturing Method (Energy Storage Device Separator)> A manufacturing method (for energy storage device separators) may include, for example, a coating step of coating a substrate with an energy storage device separator slurry, and a drying step of drying the coated energy storage device separator slurry.

[0321] (Coating process) Coating methods include, for example, coating methods, printing methods, transfer methods, and immersion methods.

[0322] Coating methods include, for example, blades, rods, reverse rolls, lips, dies, curtains, and air knives.

[0323] Printing methods include, for example, flexographic, screen printing, offset printing, gravure printing, and inkjet printing.

[0324] Examples of transfer methods include roll transfer and film transfer.

[0325] Immersion methods include, for example, dipping.

[0326] (drying process) Drying methods include, for example, air drying, irradiation drying, and vacuum drying.

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

[0328] Irradiation drying methods include, for example, infrared irradiation drying, far-infrared irradiation drying, and electron beam irradiation drying.

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

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

[0331] The manufacturing method (for the energy storage device separator) may optionally include a pressing process.

[0332] Examples of pressing methods include die presses and roll presses.

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

[0334] [Energy storage device separator / electrode stack] This disclosure relates to an energy storage device separator / electrode laminate having a dried material of the above-mentioned energy storage device slurry on the active material side of the electrode.

[0335] The energy storage device separator / electrode laminate is obtained by applying the above-mentioned energy storage device slurry to the electrodes and drying it.

[0336] Examples of manufacturing methods (energy storage device separator / electrode laminate) include methods that include the following steps. (1) Step of applying an electrode material-containing slurry to the current collector. (2) Step of drying the slurry containing electrode material (3) Process of pressing the dried slurry containing electrode material. (4) Step of applying energy storage device separator slurry to the dried slurry containing electrode material. (5) Process of drying the energy storage device separator slurry

[0337] Examples of application methods, drying methods, and pressing methods include the methods described above.

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

[0339] [Energy storage devices] This disclosure relates to an energy storage device.

[0340] In one embodiment, the energy storage device includes the energy storage device electrodes.

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

[0342] In one embodiment, the energy storage device includes the energy storage device separator / electrode laminate.

[0343] (electrolyte) The energy storage device may optionally include an electrolyte. Examples of the electrolyte include a solution obtained by dissolving a supporting electrolyte in a non-aqueous solvent.

[0344] Non-aqueous solvents can be used alone or in combination of two or more.

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

[0346] Examples of linear carbonate solvents include diethyl carbonate, dimethyl carbonate, and ethyl methyl carbonate.

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

[0348] Examples of chain-like ether solvents include 1,2-dimethoxyethane.

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

[0350] Examples of linear ester solvents include methyl formate, methyl acetate, and methyl propionate.

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

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

[0353] Supporting electrolytes can be used individually or in combination of two or more types.

[0354] Examples of supporting electrolytes include lithium salts. Examples of lithium salts include LiPF6, LiAsF6, LiBF4, LiSbF6, LiAlCl4, LiClO4, CF3SO3Li, C4F9SO3Li, CF3COOLi, (CF3CO)2NLi, (CF3SO2)2NLi, and (C2F5SO2)NLi. In one embodiment, the supporting electrolyte is preferably LiPF6, LiClO4, or CF3SO3Li.

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

[0356] Examples of film-forming agents include carbonates, alkenesulfides, sultones, and acid anhydrides.

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

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

[0359] Examples of sultones include 1,3-propanesultone and 1,4-butanesultone.

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

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

[0362] Examples of the forms (energy storage devices) include a cylinder type with sheet electrodes and separators arranged in a spiral, an inside-out cylinder type combining pellet electrodes and separators, and a coin type with stacked pellet electrodes and separators.

[0363] Examples of manufacturing methods (for energy storage devices) include the method described in Japanese Patent Publication No. 2013-089437.

[0364] Applications (energy storage devices) include, for example, batteries, non-aqueous secondary batteries, lithium-ion batteries, sodium-ion batteries, etc. [Examples]

[0365] The present invention will be specifically described below through examples and comparative examples. However, the above description and the following examples are not intended to limit the present invention. The present invention is limited only to the claims. Unless otherwise specified below, numerical values ​​such as parts and percentages are based on mass.

[0366] Example 1 In a reaction apparatus equipped with a stirrer, thermometer, reflux condenser, nitrogen gas inlet tube, and three dropping funnels, 733.6 g of deionized 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. After removing oxygen from the reaction system with nitrogen gas, the temperature was raised to 55°C. 0.116 g (0.1 mass%) of 2,2'-azobis-2-amidinopropane dihydrochloride (manufactured by Nippo Chemical Co., Ltd., product name "NC-32P") and 5 g of deionized water were added, and the temperature was raised to 80°C for 3 hours. Next, 1.16 g (1% by mass) of 2,2'-azobis-2-amidinopropane dihydrochloride (manufactured by Nippo Chemical Co., Ltd., product name "NC-32P") was added, and the reaction was carried out at 80°C for 2 hours to produce an aqueous solution of energy storage device binder.

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

[0368] <Preparation of hydrolyzed partial condensates of polyalkoxysilanes> In a reaction apparatus equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 100 g of deionized water, 100 g of methanol, and 200 g of 3-aminopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., product name "KBM-903") were added and the reaction was carried out at 25°C for 0.5 hours to obtain a homogeneous aqueous solution containing a hydrolyzed partial condensate of polyalkoxysilane with a degree of condensation of 1.4 and a weight-average molecular weight of 160.

[0369] If the amount of Si-HC in the table was not zero, the hydrolyzed partial condensate of the polyalkoxysilane described above was added to the aqueous solution in the amount shown in the table below. The aqueous solution was then obtained by stirring for 30 minutes.

[0370] [Table 1]

[0371] • AM: Acrylamide AA: Acrylic acid AN: Acrylonitrile • SMAS: Sodium methallyl sulfonate Na: Sodium hydroxide • Ca: Calcium hydroxide • Si-HC: Hydrolyzed partial condensate of polyalkoxysilane APS: Ammonium persulfate SPS: Sodium Persulfate • KPS: Potassium persulfate "Neutralization rate" refers to the ratio of carboxyl groups in an acrylic acid unit to 100 mole percent.

[0372] The monomer content was measured as follows. (1) Preparation (standard solution) Monomers ((meth)acrylamide, (meth)acrylonitrile) were collected in 20 mL screw-cap tubes and diluted with ultrapure water to prepare standard aqueous solutions at concentrations of 2000 ppm, 1000 ppm, 500 ppm, 100 ppm, 10 ppm, 1 ppm, and 0.5 ppm. (2) (meth)acrylamide calibration curve A calibration curve was created by measuring using a standard solution under the following conditions. Measuring equipment: HPLC (Agilent 1260 Infinity2 PrimeLC) Column: InertSustain AQ-C18 Column oven temperature: 40℃ Eluent: Phosphate buffer (sodium dihydrogen phosphate / ultrapure water = 8 / 1000 (v / v) aqueous solution) Measured concentration: 0.20% by mass (concentration of water-soluble polymer) Injection volume: 4μL (3) Preparation (sample) Each sample was diluted 50-fold in a screw-cap tube. Measurements were taken under the conditions of (2), and the monomer content in the sample was determined from the calibration curve.

[0373] <Breaking Strength> An aqueous solution of energy storage device binder was applied to the surface of a polypropylene plate and heated in an oven at 120°C until a constant weight was achieved, yielding the non-volatile residue of the energy storage device binder aqueous solution. The obtained non-volatile residue was molded into a shape measuring 50 mm in length, 20 mm in width, and with a film thickness of 50 μm, to produce a molded film composed of the non-volatile residue of the energy storage device binder aqueous solution. The tensile strength of the fabricated molded film was measured using a universal testing machine (AGX-V, manufactured by Shimadzu Corporation) at a tensile speed of 50 mm / min. A:30MPa or more B: Less than 30 MPa

[0374] <Pencil hardness> A film was manufactured by coating and drying a binder aqueous solution under the following conditions. The pencil hardness (of the film) was measured using the following test method. Substrate: Glass plate Coating method: Applicator (thickness 200 μm) Drying conditions: 100°C, 30 minutes Test method: General test method of JIS K-5401 A: 3H or more B: 2H or less

[0375] <Operational evaluation (electrodes of energy storage device)> (1-1) Manufacturing (Energy storage device electrode slurry) Using a commercially available rotary-orbit mixer (product name "Awatori Rentaro", manufactured by Thinky Co., Ltd.), 7 parts by mass of the energy storage device binder aqueous solution obtained in the example (calculated on a non-volatile content basis), 50 parts by mass of silicon monoxide particles with a D50 of 5 μm, and 50 parts by mass of natural graphite (manufactured by Ito Graphite Industry Co., Ltd., product name "Z-5F") were mixed in a container specifically for the mixer. Ion-exchanged water was added to the mixture to a non-volatile content concentration of 40%, and the container was set in the mixer. Next, the mixture was kneaded at 2000 rpm for 10 minutes, followed by degassing for 1 minute to obtain an energy storage device electrode slurry.

[0376] (1-2) Manufacturing (electrodes for energy storage devices) The above-mentioned energy storage device electrode slurry was uniformly applied to the surface of a current collector made of copper foil using the doctor blade method so that the film thickness after drying was 25 μm. After drying at 80°C for 30 minutes, the electrode was obtained by heat treatment at 100°C for 60 minutes. Subsequently, the density of the film (electrode active material layer) was 1.2 g / cm³. 3 The electrodes were obtained by press-forming them using a roll press machine.

[0377] (1-3) Manufacturing (energy storage devices) In an argon-purged glove box, the electrodes described above were punched out to a diameter of 16 mm and placed on a two-electrode coin cell (manufactured by Hosen Co., Ltd., product name "HS Flat Cell"). Next, a separator made of a porous polypropylene membrane punched out to a diameter of 24 mm (manufactured by CS TECH CO., LTD, product name "Selion P2010") was placed on top. Then, 500 μL of electrolyte was injected to prevent air from entering, and a commercially available metallic lithium foil punched out to 16 mm was placed on top. The outer body of the two-electrode coin cell was then closed with screws to seal it, thereby assembling the energy storage device (lithium half cell). The electrolyte used here was a solution of ethylene carbonate / dimethyl carbonate = 3 / 7 (volume ratio) in which LiPF6 was dissolved at a concentration of 1 mol / L.

[0378] (1-4) Charge / discharge measurement A lithium half-cell was placed in a constant temperature bath at 25°C, and charging was started at a constant current (0.1C). Charging was completed (cutoff) when the voltage reached 0.01V. Next, discharging was started at a constant current (0.1C), and the discharge was completed (cutoff) when the voltage reached 1.0V. This charge-discharge cycle was repeated 30 times. In the above measurement conditions, "1C" refers to the current value at which a cell with a certain electrical capacity will complete discharge in one hour. For example, "0.1C" refers to the current value at which discharge will be completed in 10 hours, and "10C" refers to the current value at which discharge will be completed in 0.1 hours.

[0379] <Initial Coulomb Efficiency> The initial Coulomb efficiency was determined using the following formula based on the initial charge capacity (mAh) and initial discharge capacity (mAh) values ​​obtained during charge-discharge cycle tests conducted at room temperature (25°C). Initial Coulomb Efficiency = (Initial Discharge Capacity) / (Initial Charge Capacity) × 100 (%) A: Over 65% B: 60% or more but less than 65% C: Less than 60%

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

[0381] <Operational evaluation (energy storage device separator)> (2-1) Manufacturing (Energy storage device separator slurry) 5 parts by mass of the energy storage device binder aqueous solution obtained in the example (calculated on a non-volatile content basis) 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 in a homogenizer (IKA T25 digital ULTRA-TURRAX) at 15,000 rpm for 60 minutes. Deionized water was then added to adjust the viscosity, and an energy storage device separator slurry was produced.

[0382] (2-2) Manufacturing (Separator): Lamination of separator slurry layers (coating layers) A single-layer polyethylene separator substrate (PE substrate) with a width of 250 mm, a length of 200 mm, and a thickness of 6 μm, manufactured by a wet process, was prepared. The above energy storage device separator slurry was coated onto one surface of the separator using a gravure coater so that the thickness after drying would be 3.0 μm, and then dried to obtain an energy storage device separator.

[0383] (2-3) Manufacturing (energy storage devices) In the above (1-3) manufacturing (energy storage device), the energy storage device was manufactured using the same method, except that the separator manufactured above was replaced.

[0384] The energy storage device having an energy storage device separator manufactured using the energy storage device binder aqueous solution of the example functioned without any problems.

Claims

1. Aqueous solution of a battery storage device binder, The aqueous solution of the energy storage device binder comprises a water-soluble polymer, (meth)acrylamide, and (meth)acrylonitrile. The water-soluble polymer contains 39.9 mol% or more of (meth)acrylamide units and 0.01% to 1% by mass of polymerization initiator units. An aqueous solution of a battery storage device binder, wherein the content of (meth)acrylamide relative to the water-soluble polymer is 0.01 ppm by mass or more and less than 1000 ppm by mass.

2. Energy storage device slurry, The energy storage device slurry comprises a water-soluble polymer, (meth)acrylamide, (meth)acrylonitrile, and water. The water-soluble polymer contains 39.9 mol% or more of (meth)acrylamide units and 0.01% to 1% by mass of polymerization initiator units. A slurry for an energy storage device, wherein the content of the (meth)acrylamide relative to the water-soluble polymer is 0.01 ppm by mass or more and less than 1000 ppm by mass.

3. A slurry for an energy storage device according to claim 2, comprising an electrode active material.

4. The energy storage device slurry according to claim 2, comprising non-conductive particles.

5. An electrode for a power storage device, having a dried material of the power storage device slurry described in claim 2 or 3 on a current collector.

6. A storage device separator having a dried product of the storage device slurry described in claim 2 or 4 on a substrate.

7. A storage device separator / electrode laminate having a dried product of the storage device slurry according to claim 2 or 4 on the active material side of the electrode.

8. A power storage device comprising the power storage device electrode described in claim 5.

9. A storage device comprising the energy storage device separator described in claim 6.

10. A storage device comprising the energy storage device separator / electrode laminate described in claim 7.

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