Power storage device aqueous solution, power storage device slurry, power storage device electrode, power storage device separator, power storage device separator / electrode laminate, power storage device electrolyte, and power storage device

Abstract

Disclosed is a power storage device aqueous solution which contains a water-soluble polymer, wherein: the water-soluble polymer contains 20% by mole to 95% by mole of an alkyl (meth)acrylamide unit, 0.1% by mole to 40% by mole of an unsaturated carboxylic acid unit, and 2.5% by mole to 79.9% by mole of an unsaturated carboxylic acid salt unit; and a B-type viscosity (at 25°C with a nonvolatile content of 3% by mass) is 155 mPa∙s to 10,000 mPa∙s.

Description

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

[0001] The present disclosure relates to an aqueous solution for an electricity storage device, a slurry for an electricity storage device, an electrode for an electricity storage device, a separator for an electricity storage device, a separator / electrode laminate for an electricity storage device, an electrolyte for an electricity storage device, and an electricity storage device.

[0002] The applicant is investigating the use of water-soluble polymers as binders in electricity storage devices.

[0003] Japanese Patent Application Laid-Open No. 2018-006333

[0004] The problem to be solved by the present invention is to provide an aqueous solution for an electricity storage device for producing an electricity storage device having excellent adhesion (after electrode production and after electrolyte impregnation).

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

[0006] The present disclosure provides the following: (Item 1) An aqueous solution for an electricity storage device, the aqueous solution for an electricity storage device comprising a water-soluble polymer, the water-soluble polymer comprising 20 mol % to 95 mol % of alkyl(meth)acrylamide units, 0.1 mol % to 40 mol % of unsaturated carboxylic acid units, and 2.5 mol % to 79.9 mol % of unsaturated carboxylate units, and the aqueous solution for an electricity storage device has a Brookfield viscosity (25°C, non-volatile content 3% by mass) of 155 mPa·s to 10,000 mPa·s. (Item 2) An electricity storage device slurry comprising a water-soluble polymer and water, wherein the water-soluble polymer comprises 20 mol % to 95 mol % of alkyl(meth)acrylamide units, 0.1 mol % to 40 mol % of unsaturated carboxylic acid units, and 2.5 mol % to 79.9 mol % of unsaturated carboxylate units, and wherein the water-soluble polymer has a Brookfield viscosity (25°C, non-volatile content 3% by mass) of 155 mPa·s to 10,000 mPa·s. (Item 3) The electricity storage device slurry according to the above item, comprising an electrode active material. (Item 4) The electricity storage device slurry according to the above item, comprising non-conductive particles. (Item 5) An electricity storage device electrode having a current collector formed from a dried product of the electricity storage device slurry according to any one of the above items. (Item 6) An electricity storage device separator having a substrate formed from a dried product of the electricity storage device slurry according to any one of the above items. (Item 7) An electricity storage device separator / electrode laminate having a dried product of the electricity storage device slurry according to any one of the above items on the active material side of an electrode. (Item 8) An electricity storage device electrolyte which is a gelled product of the electricity storage device aqueous solution according to the above items. (Item 9) An electricity storage device comprising the electricity storage device electrode according to the above items. (Item 10) An electricity storage device comprising the electricity storage device separator according to the above items. (Item 11) An electricity storage device comprising the electricity storage device separator / electrode laminate according to the above items. (Item 12) An electricity storage device comprising the electricity storage device electrolyte according to the above items. (Item A1) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the above items, in which the mol % content (alkyl(meth)acrylamide units / water-soluble polymer) is 25 mol % to 90 mol %.(Item A2) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mole percent content (alkyl(meth)acrylamide units / water-soluble polymer) is 30 mole percent to 85 mole percent. (Item A3) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mole percent content (alkyl(meth)acrylamide units / water-soluble polymer) is 55 mole percent to 80 mole percent. (Item A4) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass percent content (alkyl(meth)acrylamide units / water-soluble polymer) is 20 mass percent to 95 mass percent. (Item A5) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass percent content (alkyl(meth)acrylamide units / water-soluble polymer) is 25 mass percent to 90 mass percent. (Item A6) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content (alkyl(meth)acrylamide units / water-soluble polymer) is 30 mass % to 85 mass %. (Item A7) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content (alkyl(meth)acrylamide units / water-soluble polymer) is 55 mass % to 80 mass %. (Item A8) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the molar content (unsaturated carboxylic acid units / water-soluble polymer) is 0.2 mol % to 35 mol %. (Item A9) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the molar content (unsaturated carboxylic acid units / water-soluble polymer) is 0.3 mol % to 10 mol %. (Item A10) The electrical storage device aqueous solution or electrical storage device slurry according to any one of the preceding items, wherein the mole percent content (unsaturated carboxylic acid units / water-soluble polymer) is 0.4 mole percent to 5 mole percent. (Item A11) The electrical storage device aqueous solution or electrical storage device slurry according to any one of the preceding items, wherein the mass percent content (unsaturated carboxylic acid units / water-soluble polymer) is 0.1 mass percent to 40 mass percent.(Item A12) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content (unsaturated carboxylic acid units / water-soluble polymer) is 0.2 mass % to 35 mass %. (Item A13) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content (unsaturated carboxylic acid units / water-soluble polymer) is 0.3 mass % to 10 mass %. (Item A14) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content (unsaturated carboxylic acid units / water-soluble polymer) is 0.4 mass % to 5 mass %. (Item A15) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mol % content (unsaturated carboxylic acid salt units / water-soluble polymer) is 4 mol % to 70 mol %. (Item A16) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mol% content (unsaturated carboxylate units / water-soluble polymer) is 5 mol% to 20 mol%. (Item A17) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mol% content (unsaturated carboxylate units / water-soluble polymer) is 10 mol% to 17 mol%. (Item A18) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass% content (unsaturated carboxylate units / water-soluble polymer) is 2.5 mass% to 79 mass%. (Item A19) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass% content (unsaturated carboxylate units / water-soluble polymer) is 4 mass% to 70 mass%. (Item A20) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content (unsaturated carboxylate units / water-soluble polymer) is 5 mass % to 20 mass %. (Item A21) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content (unsaturated carboxylate units / water-soluble polymer) is 10 mass % to 17 mass %. (Item A22) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mole % content ((meth)acrylamide units / water-soluble polymer) is 0 mole % to 99.998 mole %.(Item A23) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mole percent content ((meth)acrylamide units / water-soluble polymer) is 10 mole percent to 99.9 mole percent. (Item A24) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mole percent content ((meth)acrylamide units / water-soluble polymer) is 20 mole percent or more and less than 99.65 mole percent. (Item A25) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mole percent content ((meth)acrylamide units / water-soluble polymer) is 55 mole percent to 95 mole percent. (Item A26) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass percent content ((meth)acrylamide units / water-soluble polymer) is 0 mass percent to 99.998 mass percent. (Item A27) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content ((meth)acrylamide units / water-soluble polymer) is 10 mass % to 99.9 mass %. (Item A28) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content ((meth)acrylamide units / water-soluble polymer) is 20 mass % or more and less than 99.65 mass %. (Item A29) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content ((meth)acrylamide units / water-soluble polymer) is 55 mass % to 95 mass %. (Item A30) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the molar content (unsaturated hydrocarbon sulfonic acid (salt) units / water-soluble polymer) is 0 mol % to 1.0 mol %. (Item A31) The electrical storage device aqueous solution or electrical storage device slurry according to any one of the preceding items, wherein the mol % content (unsaturated hydrocarbon sulfonic acid (salt) units / water-soluble polymer) is less than 0.1 mol %. (Item A32) The electrical storage device aqueous solution or electrical storage device slurry according to any one of the preceding items, wherein the mol % content (unsaturated hydrocarbon sulfonic acid (salt) units / water-soluble polymer) is less than 0.01 mol %.(Item A33) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mole percent content (unsaturated hydrocarbon sulfonic acid (salt) units / water-soluble polymer) is 0 mole percent. (Item A34) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass percent content (unsaturated hydrocarbon sulfonic acid (salt) units / water-soluble polymer) is 0 mass % to 1.0 mass %. (Item A35) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass percent content (unsaturated hydrocarbon sulfonic acid (salt) units / water-soluble polymer) is less than 0.1 mass %. (Item A36) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass percent content (unsaturated hydrocarbon sulfonic acid (salt) units / water-soluble polymer) is less than 0.01 mass %. (Item A37) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content (unsaturated hydrocarbon sulfonic acid (salt) units / water-soluble polymer) is 0 mass %. (Item A38) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mol % content (polyfunctional monomer units / water-soluble polymer) is 0 mol % to 10 mol %. (Item A39) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mol % content (polyfunctional monomer units / water-soluble polymer) is 0 mol % to 0.05 mol %. (Item A40) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mol % content (polyfunctional monomer units / water-soluble polymer) is 0.01 mol % to 0.02 mol %. (Item A41) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content (polyfunctional monomer unit / water-soluble polymer) is 0 mass % to 10 mass %. (Item A42) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content (polyfunctional monomer unit / water-soluble polymer) is 0 mass % to 0.05 mass %. (Item A43) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content (polyfunctional monomer unit / water-soluble polymer) is 0.01 mass % to 0.04 mass %.(Item A44) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mol % content (α,β-unsaturated nitrile units / water-soluble polymer) is 0 mol % to 50 mol %. (Item A45) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mol % content (α,β-unsaturated nitrile units / water-soluble polymer) is 10 mol % to 40 mol %. (Item A46) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mol % content (α,β-unsaturated nitrile units / water-soluble polymer) is 0 mol % or more and less than 10 mol %. (Item A47) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content (α,β-unsaturated nitrile units / water-soluble polymer) is 0 mass % to less than 50 mass %. (Item A48) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content (α,β-unsaturated nitrile units / water-soluble polymer) is 5 mass % to less than 30 mass %. (Item A49) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the mass % content (α,β-unsaturated nitrile units / water-soluble polymer) is 0 mass % or more and less than 10 mass %. (Item A50) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the molar content (alkoxyalkyl (meth)acrylate units / water-soluble polymer) is 0 mol % to 40 mol %. (Item A51) The electricity storage device aqueous solution or electricity storage device slurry according to any one of the preceding items, wherein the molar content (alkoxyalkyl (meth)acrylate units / water-soluble polymer) is 5 mol % to 35 mol %. (Item A52) The electrical storage device aqueous solution or electrical storage device slurry according to any one of the preceding items, wherein the mass % content (alkoxyalkyl (meth)acrylate units / water-soluble polymer) is 0 mass % to 60 mass %. (Item A53) The electrical storage device aqueous solution or electrical storage device slurry according to any one of the preceding items, wherein the mass % content (alkoxyalkyl (meth)acrylate units / water-soluble polymer) is 5 mass % to 35 mass %.

[0007] One or more of the features described above may be provided in further combinations in addition to the combinations specified.

[0008] By using the electricity storage device aqueous solution of the present disclosure, an electricity storage device having excellent adhesion (after electrode production and after impregnation with an electrolyte solution) can be manufactured.

[0009] Throughout this disclosure, the range of the numerical values ​​of each physical property, content, etc. can be set as appropriate (for example, by selecting from the values ​​described in each item below). Specifically, when A3, A2, and A1 (where A3 > A2 > A1) are exemplified as the numerical value α, the range of the numerical value α can be, 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 less than A2), 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 less than A2, greater than A2 ... and the like.

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

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

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

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

[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 the alkyl group include a linear alkyl group, a branched alkyl group, and a cycloalkyl group.

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

[0017] A "branched alkyl group" means a group that does not have a cyclic structure, in which at least one hydrogen atom of a straight-chain alkyl group is replaced with an alkyl group.

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

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

[0020] "Monocyclic ring" means a ring structure formed by covalent carbon bonds and having no internal bridges. "Fused ring" means a ring structure in which two or more monocyclic rings share two atoms (i.e., each ring shares only one edge (fused) with another). "Bridged ring" means a ring structure in which two or more monocyclic rings share three or more atoms.

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

[0022] Examples of the bridged ring cycloalkyl group include a tricyclodecyl group, an adamantyl group, and a norbornyl group.

[0023] The alkyl group also includes a group formed by combining a linear alkyl group, a branched alkyl group, and a cycloalkyl group, and examples of such a combined group include a cycloalkylalkyl group.

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

[0025] Examples of inorganic salts include sodium salts, lithium salts, calcium salts, and ammonium salts.

[0026] Examples of organic salts include amine salts.

[0027] [Electricity Storage Device Aqueous Solution: Aqueous Solution] The present disclosure relates to an electricity storage device aqueous solution, the electricity storage device aqueous solution comprising a water-soluble polymer, the water-soluble polymer comprising 20 mol % to 95 mol % of alkyl(meth)acrylamide units, 0.1 mol % to 40 mol % of unsaturated carboxylic acid units, and 2.5 mol % to 79.9 mol % of unsaturated carboxylate units, and having a Brookfield viscosity (25°C, non-volatile content 3% by mass) of 155 mPa·s to 10,000 mPa·s.

[0028] <Water-soluble polymer: polymer> The water-soluble polymers may be used alone or in combination of two or more.

[0029] "Water-soluble" means that when 0.5 g of the compound is dissolved in 100 g of water at 25°C, the water-insoluble content is less than 0.5 mass % (less than 2.5 mg).

[0030] The water-insoluble content may be, for example, 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, or 0% by mass.

[0031] (Alkyl(meth)acrylamide Unit) The alkyl(meth)acrylamides may be used alone or in combination of two or more.

[0032] "Alkyl(meth)acrylamide" means a compound in which one or more hydrogen atoms directly bonded to the nitrogen atom of (meth)acrylamide are substituted with an unsubstituted alkyl group.

[0033] Examples of alkyl(meth)acrylamides include dialkyl(meth)acrylamides and monoalkyl(meth)acrylamides.

[0034] The term "monoalkyl(meth)acrylamide" refers to a compound in which one hydrogen atom directly bonded to the nitrogen atom of (meth)acrylamide is substituted with an unsubstituted alkyl group.

[0035] Examples of the monoalkyl(meth)acrylamide include N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide, and N-propyl(meth)acrylamide.

[0036] "Dialkyl(meth)acrylamide" means a compound in which two hydrogen atoms directly bonded to the nitrogen atom of (meth)acrylamide are substituted with unsubstituted alkyl groups.

[0037] Examples of dialkyl(meth)acrylamides include N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, and N,N-dipropyl(meth)acrylamide.

[0038] Examples of the mol% content (alkyl(meth)acrylamide units / water-soluble polymer) include 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%, and 20 mol%. In one embodiment, the content is preferably 20 mol% to 95 mol%, more preferably 25 mol% to 90 mol%, even more preferably 30 mol% to 85 mol%, and particularly preferably 55 mol% to 80 mol%.

[0039] Examples of the mass% content (alkyl(meth)acrylamide units / water-soluble polymer) include 95 mass%, 90 mass%, 85 mass%, 80 mass%, 75 mass%, 70 mass%, 65 mass%, 60 mass%, 55 mass%, 50 mass%, 45 mass%, 40 mass%, 35 mass%, 30 mass%, 25 mass%, and 20 mass%. In one embodiment, the content is preferably 20 mass% to 95 mass%, more preferably 25 mass% to 90 mass%, even more preferably 30 mass% to 85 mass%, and particularly preferably 55 mass% to 80 mass%.

[0040] (Unsaturated Carboxylic Acid Unit) The unsaturated carboxylic acids may be used alone or in combination of two or more.

[0041] Examples of the unsaturated carboxylic acid include (meth)acrylic acid, crotonic acid, maleic acid, fumaric acid, and itaconic acid.

[0042] Examples of the mol% content (unsaturated carboxylic acid units / water-soluble polymer) include 40 mol%, 37 mol%, 35 mol%, 33 mol%, 30 mol%, 25 mol%, 20 mol%, 15 mol%, 10 mol%, 5 mol%, 4 mol%, 3 mol%, 2 mol%, 1 mol%, 0.9 mol%, 0.7 mol%, 0.5 mol%, 0.4 mol%, 0.2 mol%, and 0.1 mol%. In one embodiment, the content is preferably 0.1 mol% to 40 mol%, more preferably 0.2 mol% to 35 mol%, even more preferably 0.3 mol% to 10 mol%, and particularly preferably 0.4 mol% to 5 mol%.

[0043] Examples of the mass% content (unsaturated carboxylic acid unit / water-soluble polymer) include 40 mass%, 37 mass%, 35 mass%, 33 mass%, 30 mass%, 25 mass%, 20 mass%, 15 mass%, 10 mass%, 5 mass%, 4 mass%, 3 mass%, 2 mass%, 1 mass%, 0.9 mass%, 0.7 mass%, 0.5 mass%, 0.4 mass%, 0.1 mass%, etc. In one embodiment, the content is preferably 0.1 mass% to 40 mass%, more preferably 0.2 mass% to 35 mass%, even more preferably 0.3 mass% to 10 mass%, and particularly preferably 0.4 mass% to 5 mass%.

[0044] (Unsaturated Carboxylate Unit) The unsaturated carboxylate may be used alone or in combination of two or more kinds.

[0045] Examples of the unsaturated carboxylic acid salt include inorganic unsaturated carboxylic acid salts and organic unsaturated carboxylic acid salts.

[0046] Examples of the inorganic salt of unsaturated carboxylic acid include alkali metal salt of unsaturated carboxylic acid, alkaline earth metal salt of unsaturated carboxylic acid, and ammonium salt of unsaturated carboxylic acid.

[0047] Examples of the alkali metal salt of unsaturated carboxylic acid include sodium salt of unsaturated carboxylic acid and lithium salt of unsaturated carboxylic acid.

[0048] Examples of the unsaturated carboxylic acid sodium salt include sodium (meth)acrylate, sodium crotonate, sodium maleate, sodium fumarate, and sodium itaconate.

[0049] Examples of the lithium salt of unsaturated carboxylic acid include lithium (meth)acrylate, lithium crotonate, lithium maleate, lithium fumarate, and lithium itaconate.

[0050] Examples of the alkaline earth metal salt of an unsaturated carboxylic acid include calcium salt of an unsaturated carboxylic acid.

[0051] Examples of the calcium salt of unsaturated carboxylic acid include calcium (meth)acrylate, calcium crotonate, calcium maleate, calcium fumarate, and calcium itaconate.

[0052] Examples of the unsaturated carboxylic acid ammonium salt include ammonium (meth)acrylate, ammonium crotonate, ammonium maleate, ammonium fumarate, and ammonium itaconate.

[0053] Examples of the mol% content (unsaturated carboxylate units / water-soluble polymer) include 79.9 mol%, 75 mol%, 70 mol%, 67 mol%, 65 mol%, 60 mol%, 55 mol%, 50 mol%, 45 mol%, 40 mol%, 35 mol%, 30 mol%, 25 mol%, 20 mol%, 17 mol%, 15 mol%, 14.5 mol%, 14 mol%, 12 mol%, 10 mol%, 5 mol%, 4.5 mol%, 4 mol%, 3 mol%, and 2.5 mol%. In one embodiment, the content is preferably 2.5 mol% to 79 mol%, more preferably 4 mol% to 70 mol%, even more preferably 5 mol% to 20 mol%, and particularly preferably 10 mol% to 17 mol%.

[0054] Examples of the mass% content (unsaturated carboxylate unit / water-soluble polymer) include 79.9 mass%, 75 mass%, 70 mass%, 67 mass%, 65 mass%, 60 mass%, 55 mass%, 50 mass%, 45 mass%, 40 mass%, 35 mass%, 30 mass%, 25 mass%, 20 mass%, 17 mass%, 15 mass%, 14.5 mass%, 14 mass%, 12 mass%, 10 mass%, 5 mass%, 4.5 mass%, 4 mass%, 3 mass%, 2.5 mass%, etc. In one embodiment, the content is preferably 2.5 mass% to 79 mass%, more preferably 4 mass% to 70 mass%, even more preferably 5 mass% to 20 mass%, and particularly preferably 10 mass% to 17 mass%.

[0055] ((Meth)acrylamide Unit) In one embodiment, the water-soluble polymer may optionally contain a (meth)acrylamide unit. The (meth)acrylamides may be used alone or in combination of two or more.

[0056] Examples of the 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%, and 0 mol%. In one embodiment, the content is preferably 0 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%.

[0057] Examples of the mass% content ((meth)acrylamide units / water-soluble polymer) include 99.998 mass%, 99.99 mass%, 95 mass%, 90 mass%, 85 mass%, 80 mass%, 75 mass%, 70 mass%, 65 mass%, 60 mass%, 55 mass%, 50 mass%, 45 mass%, 40 mass%, 35 mass%, 30 mass%, 25 mass%, 20 mass%, 15 mass%, 10 mass%, 9 mass%, 5 mass%, 4 mass%, 2 mass%, 1 mass%, and 0 mass%. In one embodiment, the content is preferably 0 mass% to 99.998 mass%, more preferably 10 mass% to 99.9 mass%, even more preferably 20 mass% or more but less than 99 mass%, and particularly preferably 55 mass% to 95 mass%.

[0058] (Unsaturated Hydrocarbon Sulfonic Acid (Salt)) In one embodiment, the water-soluble polymer may optionally contain an unsaturated hydrocarbon sulfonic acid (salt) unit. The unsaturated hydrocarbon sulfonic acid (salt) may be used alone or in combination of two or more kinds.

[0059] The term "unsaturated hydrocarbon sulfonic acid" refers to a sulfonic acid whose structure other than the sulfonic acid (salt) group is composed solely of carbon atoms and hydrogen atoms.

[0060] Examples of the unsaturated hydrocarbon sulfonic acid (salt) include vinyl sulfonic acid, styrene sulfonic acid, (meth)allyl sulfonic acid, sodium vinyl sulfonate, sodium styrene sulfonate, and sodium (meth)allyl sulfonate.

[0061] Examples of the mol% content (unsaturated hydrocarbon sulfonic acid (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%, and 0 mol%. In one embodiment, the content is preferably 0 mol % to 1.0 mol %, more preferably less than 0.1 mol %, even more preferably less than 0.01 mol %, and particularly preferably 0 mol %.

[0062] The mass% content (unsaturated hydrocarbon sulfone (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 mass% Mass%, 0.3 mass%, 0.25 mass%, 0.20 mass%, 0.15 mass%, 0.10 mass%, 0.08 mass%, 0.06 mass%, 0.05 mass%, 0.0 Examples include 3% 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 content is preferably 0% by mass to 1.0% by mass, more preferably less than 0.1% by mass, even more preferably less than 0.01% by mass, and particularly preferably 0% by mass.

[0063] (Multifunctional Monomer) In one embodiment, the water-soluble polymer may optionally contain a multifunctional monomer unit. The multifunctional monomer may be used alone or in combination of two or more types.

[0064] "Polyfunctional monomer" means a monomer having two or more ethylenically unsaturated double bonds.

[0065] Examples of the polyfunctional monomer include polyfunctional (meth)acrylamide compounds, tri(allyl group)-containing monomers, and tri((meth)acryloyl group)-containing triazines.

[0066] The term "polyfunctional (meth)acrylamide compound" refers to a compound having two or more (meth)acrylamide groups. (In the formula, R １ is a hydrogen atom or a methyl group.

[0067] Examples of polyfunctional (meth)acrylamide compounds include N,N'-methylenebis(meth)acrylamide, N,N'-ethylenebis(meth)acrylamide, N-[tris(3-(meth)acrylamidopropoxymethyl)methyl](meth)acrylamide, N,N-bis(2-(meth)acrylamidoethyl)(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}.

[0068] Examples of tri(allyl group)-containing monomers include triallyl isocyanurate, triallyl trimellitate, triallylamine, and triallyl(meth)acrylamide.

[0069] 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.

[0070] Examples of the mol% content (polyfunctional monomer unit / 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%, 0.02 mol%, 0.01 mol%, and 0 mol%. In one embodiment, the content is preferably 0 mol% to 10 mol%, more preferably 0 mol% to 0.05 mol%, and even more preferably 0.01 mol% to 0.02 mol%.

[0071] Examples of the mass% content (polyfunctional monomer unit / water-soluble polymer) include 10 mass%, 9 mass%, 8 mass%, 7 mass%, 6 mass%, 5 mass%, 4 mass%, 3 mass%, 2 mass%, 1 mass%, 0.9 mass%, 0.7 mass%, 0.5 mass%, 0.3 mass%, 0.1 mass%, 0.05 mass%, 0.04 mass%, 0.02 mass%, 0.01 mass%, 0 mass%, etc. In one embodiment, the content is preferably 0 mass% to 10 mass%, more preferably 0 mass% to 0.05 mass%, and even more preferably 0.01 mass% to 0.04 mass%.

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

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

[0074] Examples of the 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 content is preferably 0 mol% to 50 mol%, more preferably 10 mol% to 40 mol%, and even more preferably 0 mol% or more and less than 10 mol%.

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

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

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

[0078] Examples of the mol% 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 content is preferably 0 mol% to 40 mol%, and more preferably 5 mol% to 35 mol%.

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

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

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

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

[0083] Examples of hydroxyl group-containing linear (meth)acrylic 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-methyl-propyl (meth)acrylate, 2-hydroxy-1-methyl-propyl (meth)acrylate, 3-hydroxy-1-methyl-propyl (meth)acrylate, 1-ethyl-2-hydroxyethyl (meth)acrylate, 1-hydroxy-2-methyl-propyl (meth)acrylate, 2-hydroxy-2-methyl-propyl (meth)acrylate, 3-hydroxy-2-methyl-propyl (meth)acrylate, and 1,1-dimethyl-2-hydroxyethyl (meth)acrylate.

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

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

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

[0088] Examples of 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 the hydroxycycloalkyl vinyl ether 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, and decamethylene glycol monovinyl ether.

[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, and decaethylene glycol monovinyl ether.

[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, and decapropylene glycol monovinyl ether.

[0094] Examples of the mol% content (hydroxyl group-containing monomer unit / 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 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 the mass% content (hydroxyl group-containing monomer unit / water-soluble polymer) include 85 mass%, 80 mass%, 75 mass%, 70 mass%, 65 mass%, 60 mass%, 55 mass%, 50 mass%, 45 mass%, 40 mass%, 35 mass%, 30 mass%, 25 mass%, 20 mass%, 15 mass%, 10 mass%, 9 mass%, 5 mass%, 4 mass%, 2 mass%, 1 mass%, 0 mass%, etc. In one embodiment, the content is preferably 0 mass% to 85 mass%, more preferably 10 mass% to 70 mass%, and even more preferably 25 mass% to 45 mass%.

[0096] (Monomers other than those mentioned above: other components) The water-soluble polymer may optionally contain units of monomers other than those mentioned above (other components). The other components may be used alone or in combination of two or more.

[0097] Examples of other components include unsaturated phosphoric acid (salts), alkyl (meth)acrylic acid esters, conjugated dienes, aromatic vinyl compounds, and heteroatom-containing group-substituted (meth)acrylamide group-containing compounds.

[0098] Examples of unsaturated phosphoric acid (salts) include vinylphosphonic acid, vinyl phosphate, bis((meth)acryloxyethyl)phosphate, diphenyl-2-(meth)acryloyloxyethyl phosphate, dibutyl-2-(meth)acryloyloxyethyl phosphate, dioctyl-2-(meth)acryloyloxyethyl phosphate, monomethyl-2-(meth)acryloyloxyethyl phosphate, and 3-(meth)acryloxy-2-hydroxypropanephosphoric acid.

[0099] Examples of the alkyl(meth)acrylate include linear alkyl(meth)acrylate, branched alkyl(meth)acrylate, and alicyclic alkyl(meth)acrylate.

[0100] 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.

[0101] 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.

[0102] Examples of the alicyclic alkyl (meth)acrylate include cyclohexyl (meth)acrylate.

[0103] Examples of conjugated dienes include 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene, 2-chloro-1,3-butadiene, substituted straight-chain conjugated pentadiene, and substituted and side-chain conjugated hexadiene.

[0104] Examples of aromatic vinyl compounds include styrene, α-methylstyrene, p-methylstyrene, vinyltoluene, chlorostyrene, and divinylbenzene.

[0105] Examples of the heteroatom-containing group-substituted (meth)acrylamide group-containing compound include N-methylol(meth)acrylamide, hydroxyethyl(meth)acrylamide, dimethylaminopropyl(meth)acrylamide, diacetone(meth)acrylamide, dimethylaminopropyl(meth)acrylamide methyl chloride quaternary salt, dimethylaminoethyl(meth)acrylate benzyl chloride quaternary salt, and (meth)acryloylmorpholine.

[0106] Examples of the mass% content (other component units / water-soluble polymer) include less than 10 mass%, less than 9 mass%, less than 7 mass%, less than 5 mass%, less than 4 mass%, less than 2 mass%, less than 1 mass%, less than 0.9 mass%, less than 0.7 mass%, less than 0.5 mass%, less than 0.4 mass%, less than 0.2 mass%, less than 0.1 mass%, and 0 mass%, etc. In one embodiment, the content is preferably less than 10 mass%, more preferably less than 5 mass%, even more preferably less than 1 mass%, and particularly preferably 0 mass%.

[0107] The mol% content (other component units / water-soluble polymer) is, for example, less than 10 mol%, less than 9 mol%, less than 7 mol%, less than 5 mol%, less than 4 mol%, less than 3 mol%, less than 2 mol%, less than 1 mol%, or 0 mol%. In one embodiment, the content is preferably less than 10 mol%, more preferably less than 5 mol%, even more preferably less than 1 mol%, and particularly preferably 0 mol%.

[0108] <Production Method (Water-Soluble Poly(meth)acrylamide)> Examples of the production method (water-soluble poly(meth)acrylamide) include radical polymerization. In one embodiment, the polymerization temperature is preferably 50°C to 100°C. In one embodiment, the polymerization time is preferably 1 hour to 10 hours.

[0109] Examples of the radical polymerization initiator include an azo-based initiator, a persulfate, and a redox-based polymerization initiator.

[0110] Examples of the azo initiator include 2,2'-azobis-2-amidinopropane dihydrochloride.

[0111] Examples of persulfates include potassium persulfate and ammonium persulfate.

[0112] Examples of the redox polymerization initiator include a system in which the above-mentioned persulfate is combined with a reducing agent.

[0113] The reducing agent may, for example, be sodium hydrogen sulfite.

[0114] The amount used in mass % (radical polymerization initiator / monomer group) is preferably 0.05 mass % to 5.0 mass %, more preferably 0.1 mass % to 3.0 mass %.

[0115] <Physical Properties (Water-Soluble Polymer), etc.> Examples of the weight-average molecular weight (water-soluble polymer: Mw) include 6,000,000, 5,500,000, 5,000,000, 4,500,000, 4,000,000, 3,500,000, 3,000,000, 2,000,000, 1,500,000, 1,000,000, 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 weight-average molecular weight (Mw) is preferably 100,000 to 6,000,000, and more preferably 350,000 to 6,000,000.

[0116] Examples of number average molecular weights (water-soluble polymer: Mn) include 6,000,000, 5,500,000, 5,000,000, 4,500,000, 4,000,000, 3,500,000, 3,000,000, 2,000,000, 1,500,000, 1,000,000, 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 number average molecular weight (Mn) is preferably 10,000 or more.

[0117] Examples of the molecular weight distribution (water-soluble polymer: Mw / Mn) include 15, 14, 13, 11, 10, 9, 7.5, 5, 4, 3, 2.9, 2.5, 2, 1.5, and 1.1. In one embodiment, the molecular weight distribution (Mw / Mn) is preferably 1.1 to 15.

[0118] 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 Column: TSKgel guardcolumn PWXL, TSK-GEL G4000, TSK-GEL α-M (all manufactured by Tosoh Corporation) Eluent: 0.2 M NaNO ３ 50 mM phosphate buffer / acetonitrile = 90 / 10 (v / v) aqueous solution Column temperature: 40°C Calibration curve: standard polyethylene oxide-polyethylene glycol Measured concentration: 0.10 mass% (water-soluble polymer concentration) Filter: cellulose acetate cartridge filter (Tosoh Corporation, Myshoridisc W-13-2, pore size 0.2 μm)

[0119] The Brookfield viscosity (electrical storage device aqueous solution, 25°C, non-volatile content 3% by mass) is, for example, 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, 2,500 mPa·s, 2,250 mPa·s, 2,000 mPa·s, and 1,890 mPa·s. , 1600 mPa·s, 1200 mPa·s, 1000 mPa·s, 900 mPa·s, 750 mPa·s, 700 mPa·s, 660 mPa·s, 500 mPa·s, 310 mPa·s, 300 mPa·s, 275 mPa·s, 250 mPa·s, 225 mPa·s, 200 mPa·s, 175 mPa·s, 155 mPa·s, etc. In one embodiment, the Brookfield viscosity is preferably 155 mPa·s to 10,000 mPa·s, more preferably 155 mPa·s to 2,500 mPa·s, even more preferably 300 mPa·s to 10,000 mPa·s, and still more preferably 300 mPa·s to 2,500 mPa·s.

[0120] The measurement conditions (B-type viscosity) are as follows: Non-volatile content: 3% by mass Measurement temperature: 25°C B-type viscometer: Toki Sangyo Co., Ltd., product name "B-type viscometer model TVB-10" Viscosity less than 100 mPa·s: No. 1 rotor, rotation speed 60 rpm Viscosity 100 mPa·s to 1000 mPa·s: No. 2 rotor, rotation speed 30 rpm Viscosity 1000 mPa·s to 2500 mPa·s: No. 2 rotor, rotation speed 12 rpm Viscosity over 2500 mPa·s to 10000 mPa·s: No. 3 rotor, rotation speed 12 rpm

[0121] Examples of the glass transition temperature (water-soluble polymer) 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.

[0122] Based on the glass transition temperature (homopolymer) and mass fraction (monomer), the glass transition temperature (water-soluble polymer) can be calculated by the Fox formula: 1 / Tg=(W １ / Tg １ ) + (W ２ / Tg ２ ) + (W ３ / Tg ３ ) + ... + (W ｎ / Tg ｎ ) [In Fox's formula, Tg is the glass transition temperature (K) of the polymer to be determined, W １ ~W ｎ is the mass fraction of each monomer, Tg １ ~Tg ｎ indicates the glass transition temperature (homopolymer) (K) of each monomer.

[0123] The glass transition temperature can be measured by a DSC (differential scanning calorimeter), a DTA (differential thermal analyzer), a TMA (thermomechanical analyzer), etc. The measurement conditions (glass transition temperature) are as follows: Temperature range: -100°C to 300°C Heating rate: 10°C / min

[0124] The glass transition temperature (homopolymer) may also be a value described in a literature. Examples of the literature include "Chemical Handbook, Basics II, Edited by the Chemical Society of Japan (Revised 5th Edition)", p. 325. Examples of the glass transition temperature (homopolymer) include the following temperatures: Acrylamide: 165°C Acrylic acid: 106°C Hydroxyethyl acrylate: -15°C Acrylonitrile: 105°C

[0125] Examples of the mass % content (water-soluble polymer / electrical storage device aqueous solution) include 25 mass %, 20 mass %, 19 mass %, 15 mass %, 14 mass %, 12 mass %, 10 mass %, 9 mass %, 7 mass %, 6 mass %, 5 mass %, 4 mass %, 3 mass %, 2 mass %, 1 mass %, etc. In one embodiment, the content is preferably 1 mass % to 25 mass %.

[0126] <Water> Examples of water include ultrapure water, pure water, distilled water, ion-exchanged water, and tap water.

[0127] Examples of the mass % content (water / electrical storage device aqueous solution) include 99.9 mass %, 99 mass %, 95 mass %, 90 mass %, 85 mass %, 80 mass %, 75 mass %, etc. In one embodiment, the content is preferably 75 mass % to 99.9 mass %.

[0128] Examples of the mass ratio (water-soluble polymer / water) include 0.33, 0.30, 0.25, 0.24, 0.22, 0.20, 0.18, 0.15, 0.12, 0.10, 0.09, 0.07, 0.05, etc. In one embodiment, the mass ratio is preferably 0.05 to 0.33.

[0129] <Hydrolyzed partial condensate of polyalkoxysilane: Hydrolyzed partial condensate> In one embodiment, the aqueous solution for an electricity storage device may optionally contain a hydrolyzed partial condensate of polyalkoxysilane. The hydrolyzed partial condensates may be used alone or in combination of two or more.

[0130] Examples of polyalkoxysilanes include trialkoxysilanes and tetraalkoxysilanes.

[0131] In one embodiment, the trialkoxysilane is represented by the formula: (In the formula, R ｓ１ represents a substituted or unsubstituted alkyl or alkenyl group. ｓ２ ~R ｓ４ each independently represents an alkyl group.

[0132] The term "substituted alkyl group" refers to a group in which a hydrogen atom constituting an alkyl group is substituted with a group other than a hydrogen atom or an alkyl group.

[0133] Examples of the substituent include an amino group, a mercapto group, an isocyanate group, and a (meth)acryloyloxy group.

[0134] The amino group (amino group-containing group) is represented by the following formula: ａｍ１ R ａｍ２ (R ａｍ１ ~R ａｍ２ each independently represents a hydrogen atom, an alkyl group, or an aryl group.

[0135] 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-dimethyl-butylidene)propylamine, and N-phenyl-3-aminopropyltrimethoxysilane.

[0136] An example of the mercapto group-containing trialkoxysilane is 3-mercaptopropyltrimethoxysilane.

[0137] An example of the isocyanate group-containing trialkoxysilane is 3-isocyanatepropyltriethoxysilane.

[0138] Examples of the (meth)acryloyloxy group-containing trialkoxysilane include 3-(meth)acryloxypropyltrimethoxysilane and 3-(meth)acryloxypropyltriethoxysilane.

[0139] Examples of the alkenyl group include a vinyl group and an allyl group.

[0140] Examples of alkenyl group-containing trialkoxysilanes include vinyltrimethoxysilane and vinyltriethoxysilane.

[0141] Examples of the tetraalkoxysilane include tetramethoxysilane, tetramethoxysilane oligomer, tetraethoxysilane, and tetraethoxysilane oligomer.

[0142] The term "partial hydrolyzed condensate of polyalkoxysilane" refers to a hydrolyzed condensate in which an alkoxy group is present. In order to prevent gelation, the partial hydrolyzed condensate of polyalkoxysilane is used instead of the complete hydrolyzed condensate of polyalkoxysilane.

[0143] Examples of the condensation degree (hydrolyzed partial condensate) include 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 19, 17, 15, 14, 13, 12, 11, 10, 9, 5, 3, 2, 1.7, 1.5, 1.4, 1.2, 1.1, and 1.01. In one embodiment, the condensation degree is preferably 1.01 to 1000, and more preferably 1.01 to 100.

[0144] Examples of the weight average molecular weight (hydrolysis partial condensate) include 190,000, 170,000, 150,000, 130,000, 100,000, 90,000, 70,000, 50,000, 30,000, 20,000, 10,000, 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 weight average molecular weight is preferably 100 to 190,000.

[0145] A hydrolyzed partial condensate of polyalkoxysilane can be produced by hydrolyzing and partially condensing 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 to 60°C for 0.5 to 5.0 hours.

[0146] Examples of the acid catalyst include nitric acid, hydrochloric acid, sulfurous acid, phosphoric acid, formic acid, and acetic acid.

[0147] Examples of the base catalyst include sodium hydroxide, lithium hydroxide, potassium hydroxide, calcium hydroxide, and amine compounds.

[0148] Examples of the mass % content (hydrolyzed partial condensate / electrical storage device aqueous solution) include 10 mass %, 9 mass %, 8 mass %, 7 mass %, 6 mass %, 5 mass %, 4.5 mass %, 4 mass %, 3.5 mass %, 3 mass %, 2.5 mass %, 2 mass %, 1.5 mass %, 1 mass %, 0.9 mass %, 0.5 mass %, 0.1 mass %, 0.09 mass %, 0.05 mass %, 0.03 mass %, 0.01 mass %, etc. In one embodiment, the content is preferably 0.01 mass % to 10 mass %.

[0149] <Other Binders> In one embodiment, the electricity storage device aqueous solution may optionally contain a binder other than the water-soluble polymer (other binder). The other binders may be used alone or in combination of two or more.

[0150] Other binders include, for example, diene copolymers, fluorine-based copolymers, amide-imide copolymers, and copolymers other than those mentioned above.

[0151] Examples of the diene copolymer include styrene-butadiene copolymer, polybutadiene polymer, acrylonitrile-butadiene copolymer, methyl methacrylate-butadiene copolymer, and carboxy-modified styrene-butadiene copolymer.

[0152] 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).

[0153] Examples of the amide-imide copolymer include polyamide (PA), polyimide (PI), polyamideimide (PAI), and aromatic polyamide.

[0154] Examples of copolymers other than those mentioned above include polyurethane polymers, poly(meth)acrylate polymers, vinyl chloride polymers, vinyl acetate polymers, vinyl acetate-ethylene copolymers, polyethylene, polypropylene, polyethylene terephthalate, polystyrene polymers, and alginic acid and / or a salt thereof.

[0155] Examples of the part by mass content (other binder / 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, and 0 parts by mass. In one embodiment, the content is preferably 0 parts by mass to 100 parts by mass.

[0156] <Dispersion (Emulsion)> In one embodiment, the aqueous solution for an electricity storage device may optionally contain a dispersion (emulsion). The dispersion (emulsion) may be used alone or in combination of two or more kinds.

[0157] Examples of the dispersion (emulsion) include styrene-butadiene copolymer latex, polystyrene polymer latex, polybutadiene polymer latex, acrylonitrile-butadiene copolymer latex, polyurethane polymer latex, polymethyl methacrylate polymer latex, methyl methacrylate-butadiene copolymer latex, polyacrylate polymer latex, vinyl chloride polymer latex, vinyl acetate polymer emulsion, vinyl acetate-ethylene copolymer emulsion, polyethylene emulsion, and carboxy-modified styrene. Examples of the polymerizable polymer 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), and ethylene-tetrafluoroethylene copolymer (ETFE).

[0158] Examples of the content in parts by mass (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, and 0 parts by mass. In one embodiment, the content is preferably 0 parts by mass to 100 parts by mass.

[0159] <Thickener> In one embodiment, the electricity storage device aqueous solution may optionally contain a thickener. The thickeners may be used alone or in combination of two or more.

[0160] Examples of thickeners include cellulose-based polymers (salts), polyvinyl alcohols, (modified) poly(meth)acrylic acid (salts), polyethylene glycol, polyethylene oxide, polyvinylpyrrolidone, oxidized starch, starch phosphate, casein, modified starch, and hydrogenated acrylonitrile-butadiene copolymers.

[0161] Examples of the cellulose-based polymer (salt) include carboxymethyl cellulose, methyl cellulose, and hydroxypropyl cellulose.

[0162] Examples of polyvinyl alcohols include copolymers of maleic acid (anhydride) and / or fumaric acid with vinyl alcohol.

[0163] Examples of the content in parts by mass (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 content is preferably 0 parts by mass to 100 parts by mass.

[0164] <Additives> The aqueous solution for an electricity storage device may optionally contain, as additives, a water-soluble polymer, water, a hydrolyzed partial condensate of polyalkoxysilane, or other agents that do not fall into the category of binders, dispersions (emulsions), or thickeners. The additives may be used alone or in combination of two or more.

[0165] Examples of the additives include dispersants, leveling agents, and antioxidants.

[0166] Examples of the dispersant include anionic dispersants, cationic dispersants, nonionic dispersants, and polymer dispersants.

[0167] The leveling agent may be, for example, a surfactant.

[0168] Examples of surfactants include alkyl surfactants, silicone surfactants, fluorine surfactants, and metal surfactants.

[0169] Examples of the antioxidant include phenol compounds, hydroquinone compounds, organic phosphorus compounds, sulfur compounds, phenylenediamine compounds, and polymeric phenol compounds.

[0170] The "polymeric phenol compound" refers to a polymer having a phenol structure. The weight average molecular weight (polymeric phenol compound) is preferably 200 to 1,000, and more preferably 600 to 700.

[0171] Examples of the content in parts by mass (additive / water-soluble polymer) include less than 5 parts by mass, less than 4 parts by mass, less than 2 parts by mass, less than 1 part by mass, less than 0.9 parts by mass, less than 0.5 parts by mass, less than 0.4 parts by mass, less than 0.2 parts by mass, less than 0.1 parts by mass, less than 0.09 parts by mass, less than 0.05 parts by mass, less than 0.04 parts by mass, less than 0.02 parts by mass, less than 0.01 parts by mass, and 0 parts by mass.

[0172] Examples of the mass % content (additive / electrical storage device aqueous solution) include less than 5 mass %, less than 4 mass %, less than 2 mass %, less than 1 mass %, less than 0.9 mass %, less than 0.5 mass %, less than 0.4 mass %, less than 0.2 mass %, less than 0.1 mass %, less than 0.09 mass %, less than 0.05 mass %, less than 0.04 mass %, less than 0.02 mass %, less than 0.01 mass %, and 0 mass %.

[0173] Examples of the pH (of the electricity storage device aqueous solution) include 9, 8.9, 8.5, 8, 7.9, 7.5, 7, 6.9, 6.5, 6, 5.9, 5.6, 5.5, 5.4, 5.2, 5.1, and 5. In one embodiment, the pH is preferably 5 to 9, and more preferably 5 to 7.

[0174] The measurement conditions (pH) are as follows: Measuring equipment: Horiba Ltd., product name "pH meter D-52" Measurement temperature: 25°C

[0175] Examples of uses (electricity storage device aqueous solutions) include electricity storage device electrode binder aqueous solutions, battery electrode binder aqueous solutions, non-aqueous secondary battery electrode binder aqueous solutions, lithium ion battery electrode binder aqueous solutions, sodium ion battery electrode binder aqueous solutions, electricity storage device negative electrode binder aqueous solutions, battery negative electrode binder aqueous solutions, non-aqueous secondary battery negative electrode binder aqueous solutions, lithium ion battery negative electrode binder aqueous solutions, sodium ion battery negative electrode binder aqueous solutions, electricity storage device positive electrode binder aqueous solutions, battery positive electrode binder aqueous solutions, non-aqueous secondary battery positive electrode binder aqueous solutions, lithium ion battery positive electrode binder aqueous solutions, sodium ion battery positive electrode binder aqueous solutions, electricity storage device separator binder aqueous solutions, battery separator binder aqueous solutions, non-aqueous secondary battery separator binder aqueous solutions, lithium ion battery separator binder aqueous solutions, sodium ion battery separator binder aqueous solutions, electricity storage device electrolyte aqueous solutions, battery electrolyte aqueous solutions, non-aqueous secondary battery electrolyte aqueous solutions, lithium ion battery electrolyte aqueous solutions, and sodium ion battery electrolyte aqueous solutions.

[0176] [Electricity Storage Device Slurry: Slurry] The present disclosure relates to an electricity storage device slurry, the electricity storage device slurry comprising a water-soluble polymer and water, the water-soluble polymer comprising 20 mol % to 95 mol % of alkyl(meth)acrylamide units, 0.1 mol % to 40 mol % of unsaturated carboxylic acid units, and 2.5 mol % to 79.9 mol % of unsaturated carboxylate units, and the water-soluble polymer having a Brookfield viscosity (25°C, non-volatile content 3% by mass) of 155 mPa·s to 10,000 mPa·s.

[0177] In this disclosure, "slurry" means a suspension of liquid and solid particles.

[0178] Examples of the water-soluble polymer, water, other binders, dispersions (emulsions), and thickeners include the substances described above.

[0179] Examples of the mass % content (water-soluble polymer / slurry) include 10 mass %, 9 mass %, 8 mass %, 7 mass %, 6 mass %, 5 mass %, 4 mass %, 3 mass %, 2 mass %, 1 mass %, 0.9 mass %, 0.7 mass %, 0.5 mass %, 0.3 mass %, 0.1 mass %, etc. In one embodiment, the content is preferably 0.1 mass % to 10 mass %.

[0180] The content (other binder), content (dispersion (emulsion)), and content (thickener) may be, for example, the contents described above.

[0181] <Electrode Active Material> In one embodiment, the electricity storage device slurry contains an electrode active material. Examples of the electrode active material include a negative electrode active material and a positive electrode active material. The electrode active materials may be used alone or in combination of two or more.

[0182] (Negative Electrode Active Material) Examples of the negative electrode active material include carbon materials, materials that can be alloyed with lithium, silicon materials, and oxides containing lithium atoms.

[0183] Examples of carbon materials include graphite, low-crystalline carbon, carbon black, fullerene, carbon nanotubes, carbon nanofibers, carbon nanohorns, carbon fibrils, mesocarbon microbeads (MCMB), pitch-based carbon fibers, and activated carbon.

[0184] Examples of graphite include natural graphite and artificial graphite.

[0185] Examples of low crystalline carbon include soft carbon and hard carbon.

[0186] Examples of carbon black include ketjen black, acetylene black, channel black, lamp black, oil furnace black, and thermal black.

[0187] Examples of materials that can be alloyed with lithium include lead compounds, tin compounds, arsenic compounds, antimony compounds, and aluminum compounds.

[0188] Silicon materials include silicon, silicon oxide, silicon alloys, SiC, and SiOｘ C ｙ (0<x≦3, 0<y≦5), Si ３ N ４ , Si ２ N ２ O, SiO ｚ (0<z≦2), etc.

[0189] The silicon oxide preferably has the formula SiO ｚ (0<z≦2, preferably 0.1≦z≦1) is an example of a silicon oxide.

[0190] Examples of the silicon alloy include a silicon-titanium alloy, a silicon-zirconium alloy, a silicon-nickel alloy, a silicon-copper alloy, a silicon-iron alloy, a silicon-molybdenum alloy, etc. In one embodiment, the silicon alloy is preferably a silicon-nickel alloy or a silicon-titanium alloy, and more preferably a silicon-titanium alloy.

[0191] The molar content (silicon atoms / total metal elements) is preferably 10 mol % or more, and more preferably 20 mol % to 70 mol %.

[0192] The silicon material may be in the form of, for example, single crystal, polycrystal, or amorphous.

[0193] When a silicon material is used as the electrode active material, an electrode active material other than a silicon material may be used in combination.

[0194] Examples of electrode active materials other than silicon materials include carbon materials, conductive polymers, and composite metal oxides.

[0195] The conductive polymer may be, for example, polyacene.

[0196] The composite metal oxide is represented by, for example, the following general formula: α B β O γ(A represents an alkali metal or a transition metal. B represents at least one transition metal selected from cobalt, nickel, aluminum, tin, manganese, etc.; O represents an oxygen atom; α, β, and γ each independently satisfy the conditions 0.05<α<1.10, 0.85<β<4.00, and 1.5<γ<5.00.)

[0197] Carbon materials undergo small volume changes during lithium absorption and desorption, and therefore, when a silicon material is used as an electrode active material, it is preferable to use the silicon material in combination with a carbon material.

[0198] In one embodiment, the silicon material is preferably silicon covered with a carbon layer, or silicon oxide covered with a carbon layer.

[0199] Examples of the lithium atom-containing oxide include lithium-transition metal composite oxides, lithium-transition metal phosphate compounds, and lithium-transition metal sulfate compounds.

[0200] Examples of the lithium-transition metal composite oxide include lithium-manganese composite oxide, lithium-nickel composite oxide, lithium-cobalt composite oxide, lithium-iron composite oxide, lithium-titanium composite oxide, lithium-nickel-manganese composite oxide, and lithium-nickel-cobalt composite oxide.

[0201] In one embodiment, the mass% content (carbon material and / or material alloyed with lithium / negative electrode active material) is, for example, 100 mass%, 95 mass%, 90 mass%, 85 mass%, 80 mass%, 75 mass%, 70 mass%, 65 mass%, 60 mass%, 55 mass%, 50 mass%, 45 mass%, 40 mass%, 35 mass%, 30 mass%, 25 mass%, 20 mass%, 15 mass%, 10 mass%, 5 mass%, 0 mass%, etc. In one embodiment, the content is preferably 50 mass% or more, more preferably 80 mass% or more, even more preferably 90 mass% or more, and particularly preferably 100 mass%.

[0202] In one embodiment, the mass % content (silicon covered with a carbon layer and / or silicon oxide covered with a carbon layer / negative electrode active material) is, for example, 100 mass %, 90 mass % or more, 75 mass % or more, 50 mass % or more, 25 mass % or more, 10 mass % or more, 5 mass % or more, 2 mass % or more, 1 mass % or more, 0 mass %, etc.

[0203] In one embodiment, the mass% content (silicon material / negative electrode active material) may be, for example, 100 mass%, 95 mass%, 90 mass%, 85 mass%, 80 mass%, 75 mass%, 70 mass%, 65 mass%, 60 mass%, 55 mass%, 50 mass%, 45 mass%, 40 mass%, 35 mass%, 30 mass%, 25 mass%, 20 mass%, 15 mass%, 10 mass%, 5 mass%, 0 mass%, or the like.

[0204] (Positive Electrode Active Material) Examples of the positive electrode active material include an inorganic positive electrode active material and an organic positive electrode active material.

[0205] Examples of the positive electrode inorganic active material include transition metal oxides, lithium-transition metal composite oxides, transition metal sulfides, and activated carbon.

[0206] The inorganic active material can be partially substituted with an element. The inorganic active material can be used as an electrode active material covered with a carbon material by making a carbon source material present during reduction firing.

[0207] The positive electrode organic active material may be, for example, a conductive polymer.

[0208] Examples of the conductive polymer include polyacetylene and poly-p-phenylene.

[0209] (Physical Properties, etc. (Electrode Active Material)) The shape (electrode active material) may be, for example, a fine particle shape, a thin film shape, or the like.

[0210] 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.

[0211] The "particle diameter" refers to the maximum distance between any two points on the contour of a particle. The "average particle diameter" refers to a value calculated as the average particle diameter of particles observed within several to several tens of fields of view using an observation means such as a scanning electron microscope (SEM) or a transmission electron microscope (TEM).

[0212] Examples of the content in parts by mass (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, etc. In one embodiment, the content is preferably 0.5 parts by mass to 15 parts by mass.

[0213] (Conductive Aid) In one embodiment, the slurry may optionally contain a conductive aid. The conductive aid may be used alone or in combination of two or more kinds.

[0214] Examples of the conductive aid include fibrous carbon, carbon black, and metal fine powder.

[0215] Examples of fibrous carbon include vapor grown carbon fiber (VGCF), carbon nanotube (CNT), and carbon nanofiber (CNF).

[0216] Examples of carbon black include graphite particles, acetylene black, ketjen black, and furnace black.

[0217] Examples of the metal fine powder include copper fine powder, nickel fine powder, aluminum fine powder, silicon fine powder, and alloy fine powder.

[0218] In one embodiment, the average particle size (fine metal powder) is preferably 10 μm.

[0219] The content in parts by mass (conductive assistant / electrode active material) is preferably 0 to 10 parts by mass, and more preferably 0 to 6 parts by mass.

[0220] <Non-conductive particles> In one embodiment, the electricity storage device slurry contains non-conductive particles. The non-conductive particles may be used alone or in combination of two or more kinds.

[0221] Examples of non-conductive particles include oxide particles, hydroxide particles, nitride particles, covalently bonded crystal particles, sparingly soluble ionic crystal particles, clay fine particles, aluminum particles, barium particles, and calcium particles.

[0222] The oxide particles include, for example, 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), BaTiO ３ , ZrO, alumina-silica composite oxide, etc.

[0223] Examples of hydroxide particles include calcium hydroxide and magnesium hydroxide.

[0224] Examples of nitride particles include aluminum nitride, silicon nitride, and boron nitride.

[0225] Examples of covalently bonded crystal particles include silicon and diamond.

[0226] Examples of the sparingly soluble ionic crystal particles include barium sulfate, calcium fluoride, and barium fluoride.

[0227] Examples of the clay particles include silica, talc, montmorillonite, and the like.

[0228] The aluminum particles may be, for example, aluminum oxide (alumina), aluminum oxide hydrate (boehmite (AlOOH)), gibbsite (Al(OH) ３ ), aluminum nitride, etc.

[0229] Examples of barium particles include barium sulfate and barium fluoride.

[0230] Examples of calcium particles include calcium hydroxide, magnesium hydroxide, and calcium fluoride.

[0231] In one embodiment, the non-conductive particles are preferably boehmite, alumina, magnesium oxide, or barium sulfate.

[0232] Examples of the average particle size (non-conductive particles) include 30 μm, 25 μm, 20 μm, 15 μm, 10 μm, 5 μm, 1 μm, 0.5 μm, 0.1 μm, 0.05 μm, and 0.01 μm. In one embodiment, the average particle size is preferably 0.01 μm to 30 μm.

[0233] Examples of the mass % content (non-conductive particles / slurry) include 99.9 mass %, 95 mass %, 90 mass %, 80 mass %, 70 mass %, 60 mass %, 50 mass %, 40 mass %, 30 mass %, 20 mass %, 10 mass %, 5 mass %, 1 mass %, 0.5 mass %, 0.2 mass %, 0.1 mass %, etc. In one embodiment, the content is preferably 0.1 mass % to 99.9 mass %.

[0234] Examples of the content in parts by mass (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, and 1 part by mass. In one embodiment, the content is preferably 1 part by mass to 15 parts by mass, more preferably 1.5 parts by mass to 14 parts by mass, and even more preferably 2 parts by mass to 12 parts by mass.

[0235] <Slurry Viscosity Adjusting Solvent> The slurry viscosity adjusting solvent may be used alone or in combination of two or more kinds.

[0236] Examples of the slurry viscosity adjusting solvent include amide solvents, hydrocarbon solvents, alcohol solvents, ketone solvents, ether solvents, ester solvents, amine solvents, lactone solvents, sulfoxide / sulfone solvents, and water.

[0237] Examples of the amide solvent include N-methylpyrrolidone, dimethylformamide, and N,N-dimethylacetamide.

[0238] Examples of hydrocarbon solvents include toluene, xylene, n-dodecane, and tetralin.

[0239] Examples of the alcohol solvent include methanol, ethanol, 2-propanol, isopropyl alcohol, 2-ethyl-1-hexanol, 1-nonanol, and lauryl alcohol.

[0240] Examples of the ketone solvent include acetone, methyl ethyl ketone, cyclohexanone, phorone, acetophenone, and isophorone.

[0241] Examples of the ether solvent include dioxane and tetrahydrofuran (THF).

[0242] Examples of the ester solvent include benzyl acetate, isopentyl butyrate, methyl lactate, ethyl lactate, and butyl lactate.

[0243] Examples of the amine solvent include o-toluidine, m-toluidine, and p-toluidine.

[0244] Examples of lactone solvents include γ-butyrolactone and δ-butyrolactone.

[0245] Examples of sulfoxide / sulfone solvents include dimethyl sulfoxide and sulfolane.

[0246] In one embodiment, the slurry viscosity adjusting solvent preferably includes N-methylpyrrolidone.

[0247] Examples of the mass % content (slurry viscosity adjusting solvent / slurry) include 10 mass %, 9 mass %, 8 mass %, 7 mass %, 6 mass %, 5 mass %, 4 mass %, 3 mass %, 2 mass %, 1 mass %, 0 mass %, etc. In one embodiment, the content is preferably 0 to 10 mass %.

[0248] <Additives> The slurry may optionally contain an additive that does not fall into any of the above categories. Examples of additives include the above-mentioned agents.

[0249] The mass % content (additive / slurry) may be, for example, 0 mass % to 5 mass %, less than 1 mass %, less than 0.1 mass %, less than 0.01 mass %, or 0 mass %.

[0250] The content in parts by mass (additive / water-soluble polymer), the content in parts by mass (additive / water), the content in parts by mass (additive / hydrolyzed partial condensate of polyalkoxysilane), the content in parts by mass (additive / other binder), the content in parts by mass (additive / dispersion (emulsion)), the content in parts by mass (additive / thickener), the content in parts by mass (additive / electrode active material), the content in parts by mass (additive / non-conductive particles), the content in parts by mass (additive / slurry viscosity adjusting solvent) can be, for example, 0 parts by mass 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, 0 parts by mass, etc.

[0251] A slurry can be produced by dispersing and mixing the above agents.

[0252] Examples of mixing means (slurry) include a ball mill, a sand mill, a pigment disperser, a crusher, an ultrasonic disperser, a homogenizer, a planetary mixer, and a Hobart mixer.

[0253] Examples of uses (electricity storage device slurries) include electricity storage device electrode slurries, battery electrode slurries, non-aqueous secondary battery electrode slurries, lithium ion battery electrode slurries, sodium ion battery electrode slurries, electricity storage device negative electrode slurries, battery negative electrode slurries, non-aqueous secondary battery negative electrode slurries, lithium ion battery negative electrode slurries, sodium ion battery negative electrode slurries, electricity storage device positive electrode slurries, battery positive electrode slurries, non-aqueous secondary battery positive electrode slurries, lithium ion battery positive electrode slurries, sodium ion battery positive electrode slurries, electricity storage device separator slurries, battery separator slurries, non-aqueous secondary battery separator slurries, lithium ion battery separator slurries, and sodium ion battery separator slurries.

[0254] [Electricity Storage Device Electrode: Electrode] The present disclosure relates to an electricity storage device electrode having a dried product of the electricity storage device slurry on a current collector.

[0255] The electricity storage device electrode is obtained by applying the electricity storage device slurry to a current collector and drying it.

[0256] Examples of the current collector include metal materials and carbon materials.

[0257] Examples of metal materials include copper, iron, aluminum, nickel, stainless steel, and nickel-plated steel.

[0258] Examples of the form of the metal material include metal foil, metal cylinder, metal coil, and metal plate.

[0259] Examples of the carbon material include carbon cloth and carbon paper.

[0260] Examples of the form (carbon material) include a carbon plate, a carbon thin film, and a carbon cylinder.

[0261] Examples of the coating means include a comma coater, a gravure coater, a microgravure coater, a die coater, and a bar coater.

[0262] The drying temperature is preferably 60°C to 200°C, and more preferably 70°C to 195°C.

[0263] The dry atmosphere may be, for example, dry air or an inert atmosphere.

[0264] The thickness (electrode (cured product)) is preferably 5 μm to 300 μm, and more preferably 10 μm to 250 μm.

[0265] Examples of uses (electricity storage device electrodes) include electricity storage device positive electrodes, electricity storage device negative electrodes, battery electrodes, battery positive electrodes, battery negative electrodes, non-aqueous secondary battery electrodes, non-aqueous secondary battery positive electrodes, non-aqueous secondary battery negative electrodes, lithium ion battery electrodes, lithium ion battery positive electrodes, lithium ion battery negative electrodes, sodium ion battery electrodes, sodium ion battery positive electrodes, and sodium ion battery negative electrodes.

[0266] [Electricity Storage Device Separator: Separator] The present disclosure relates to an electricity storage device separator having a dried product of the electricity storage device slurry on a substrate.

[0267] The electricity storage device separator can be produced by applying the electricity storage device separator slurry to one or both surfaces of a substrate and drying it.

[0268] Examples of the substrate include a porous polyolefin resin substrate and a plastic nonwoven fabric.

[0269] (Porous Polyolefin Resin Substrate) The term "porous polyolefin resin substrate" refers to a microporous film containing 30% by mass or more of a resin such as a polyolefin or a mixture or copolymer thereof.

[0270] The polyolefin resin may be used alone or in combination of two or more thereof. Examples of the polyolefin resin include homopolymers and copolymers of ethylene, propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, and the like.

[0271] The three-dimensional structure (polyolefin) may be, for example, isotactic, syndiotactic, or atactic.

[0272] In one embodiment, the polyolefin resin preferably includes high density polyethylene, and more preferably includes high density polyethylene and polypropylene.

[0273] In one embodiment, the mass% content (polyolefin resin / substrate) is preferably 30 mass% to 100 mass%, more preferably 40 mass% to 100 mass%, and even more preferably 50 mass% to 100 mass%.

[0274] The porous polyolefin resin substrate may optionally contain a filler or a fiber compound, and the strength, hardness, and heat shrinkage rate of the porous polyolefin resin substrate can be controlled by the filler or fiber compound.

[0275] The porous polyolefin resin substrate may be subjected to a surface treatment, if necessary.

[0276] Examples of the surface treatment include coating treatment, electromagnetic radiation treatment, and plasma treatment.

[0277] In one embodiment, the surface treatment is preferably a coating treatment with a polar group-containing polymer. The coating treatment can improve the electrolyte impregnation property and adhesion to the dried slurry. Examples of the polar group include a carboxylic acid group, a hydroxyl group, and a sulfonic acid group.

[0278] 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.

[0279] (Plastic Nonwoven Fabric) Examples of plastic nonwoven fabric include nonwoven fabrics made only of synthetic fibers.

[0280] 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-containing resins, silicone resins, polyamideimide resins, polyphenylene sulfide resins, polyimide resins, polycarbonate resins, polyazomethine resins, polyesteramide resins, polyether ether ketone resins, poly-p-phenylene benzobisoxazole resins, polybenzimidazole resins, and ethylene-vinyl alcohol copolymer resins.

[0281] Examples of polyolefin resins include polypropylene, polyethylene, polymethylpentene, ethylene-vinyl alcohol copolymers, and olefin copolymers.

[0282] Examples of polyester-based resins include polyethylene terephthalate (PET)-based resins, polybutylene terephthalate (PBT)-based resins, polytrimethylene terephthalate (PPT)-based resins, polyethylene naphthalate (PEN)-based resins, polybutylene naphthalate-based resins, polyethylene isonaphthalate-based resins, and wholly aromatic polyester-based resins.

[0283] Examples of the acrylonitrile resin include polyacrylonitrile, copolymers of acrylonitrile with (meth)acrylic acid derivatives, vinyl acetate, and the like.

[0284] Examples of polyamide-based resins include aliphatic polyamides, wholly aromatic polyamides, and semi-aromatic polyamides.

[0285] Examples of aliphatic polyamides include nylon.

[0286] Examples of wholly aromatic polyamides include poly-p-phenylene terephthalamide, poly-p-phenylene terephthalamide-3,4-diphenyl ether terephthalamide, and poly-m-phenylene isophthalamide.

[0287] "Semi-aromatic polyamide" means a polyimide in which part of the main chain of an aromatic polyamide is an aliphatic chain.

[0288] The plastic nonwoven fabric may optionally include fibers other than synthetic resin fibers.

[0289] Examples of fibers other than synthetic resin fibers include solvent-spun cellulose, fibrillated solvent-spun cellulose, regenerated cellulose, fibrillated regenerated cellulose, natural cellulose fibers, pulped natural cellulose fibers, fibrillated natural cellulose fibers, and inorganic fibers.

[0290] The mass % content (fibers other than synthetic fibers / nonwoven fabric) is preferably 50 mass % or less, more preferably 30 mass % or less, and even more preferably 10 mass % or less.

[0291] The form (morphology) may be, for example, a single fiber, a composite fiber, or the like.

[0292] "Monofilament" means a fiber made of a single resin. "Conjugate fiber" means a fiber made of two or more resins.

[0293] Examples of the form (composite fiber) include a core-sheath type, an eccentric type, a side-by-side type, an island-in-the-sea type, an orange type, and a multi-bimetal type.

[0294] 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.

[0295] "Average fiber diameter" means the average fiber diameter of 20 fibers randomly selected from a scanning electron micrograph.

[0296] 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.

[0297] "Pore diameter" means the width of the gap between fibers. "Average pore diameter" means the average value of the pore diameters of 20 fibers randomly selected from a scanning electron microscope photograph.

[0298] In one embodiment, the thickness (plastic nonwoven fabric) is preferably 5 μm to 25 μm, and more preferably 5 μm to 15 μm.

[0299] <Method for Manufacturing Electricity Storage Device Separator> Examples of methods for manufacturing an electricity storage device separator include a coating step of coating an electricity storage device separator slurry onto a substrate, and a drying step of drying the coated electricity storage device separator slurry.

[0300] (Coating Step) Examples of the coating method include a coating method, a printing method, a transfer method, and a dipping method.

[0301] Examples of the coating method include a blade, a rod, a reverse roll, a lip, a die, a curtain, and an air knife.

[0302] Examples of printing methods include flexography, screen printing, offset printing, gravure printing, and inkjet printing.

[0303] Examples of the transfer method include roll transfer and film transfer.

[0304] The immersion method may be, for example, dipping.

[0305] (Drying Step) Examples of the drying method include air drying, irradiation drying, and vacuum drying.

[0306] Examples of the air drying include warm air drying, hot air drying, and low-humidity air drying.

[0307] Examples of irradiation drying include infrared irradiation drying, far-infrared irradiation drying, and electron beam irradiation drying.

[0308] The drying temperature is preferably 40°C to 90°C, more preferably 50°C to 80°C.

[0309] The drying time is preferably from 5 seconds to 3 minutes, and more preferably from 15 seconds to 2 minutes.

[0310] The manufacturing method (electrical storage device separator) may optionally include a pressing step.

[0311] Examples of the pressing means include a mold press and a roll press.

[0312] The electricity 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, or the like.

[0313] [Electricity Storage Device Separator / Electrode Laminate] The present disclosure relates to an electricity storage device separator / electrode laminate having the dried electricity storage device slurry on the active material side of the electrode.

[0314] The electricity storage device separator / electrode laminate is obtained by applying the electricity storage device slurry to an electrode and drying it.

[0315] The production method (electricity storage device separator / electrode laminate) may include, for example, a method including the following steps: (1) a step of applying an electrode material-containing slurry to a current collector, (2) a step of drying the electrode material-containing slurry, (3) a step of pressing the dried electrode material-containing slurry, (4) a step of applying an electricity storage device separator slurry to the dried electrode material-containing slurry, and (5) a step of drying the electricity storage device separator slurry.

[0316] Examples of the coating method, drying method, and pressing method include the methods described above.

[0317] Examples of uses (electricity storage device separator / electrode laminates) include battery separator / electrode laminates, battery separator / negative electrode laminates, battery separator / positive electrode laminates, nonaqueous secondary battery separator / electrode laminates, nonaqueous secondary battery separator / negative electrode laminates, nonaqueous secondary battery separator / positive electrode laminates, lithium ion battery separator / electrode laminates, lithium ion battery separator / negative electrode laminates, lithium ion battery separator / positive electrode laminates, sodium ion battery separator / electrode laminates, sodium ion battery separator / negative electrode laminates, and sodium ion battery separator / positive electrode laminates.

[0318] [Electricity Storage Device Electrolyte] The present disclosure relates to an electricity storage device electrolyte, which is a gel of the electricity storage device aqueous solution.

[0319] The production method (electricity storage device electrolyte) may include the following steps: (1) drying step: drying the electricity storage device aqueous solution to obtain a dried product; and (2) swelling step: swelling the dried product in a dispersion medium.

[0320] The drying conditions include, for example, the conditions described above.

[0321] The dispersion medium may be, for example, an electrolyte solution.

[0322] Examples of the electrolyte include the solutions described below.

[0323] Examples of applications (electricity storage device electrolytes) include battery electrolytes, non-aqueous secondary battery electrolytes, lithium ion battery electrolytes, and sodium ion battery electrolytes.

[0324] [Electricity Storage Device] The present disclosure relates to an electricity storage device.

[0325] In one embodiment, the power storage device includes the power storage device electrode.

[0326] In one embodiment, the power storage device includes the power storage device separator.

[0327] In one embodiment, the electrical storage device includes the electrical storage device separator / electrode laminate.

[0328] In one embodiment, the power storage device includes the power storage device electrolyte.

[0329] (Electrolyte Solution) The electricity storage device may optionally contain an electrolyte solution. Examples of the electrolyte solution include a solution in which a supporting electrolyte is dissolved in a non-aqueous solvent.

[0330] The non-aqueous solvents may be used alone or in combination of two or more.

[0331] Examples of the non-aqueous solvent include chain carbonate solvents, cyclic carbonate solvents, chain ether solvents, cyclic ether solvents, chain ester solvents, cyclic ester solvents, and acetonitrile.

[0332] Examples of the chain carbonate solvent include diethyl carbonate, dimethyl carbonate, and ethyl methyl carbonate.

[0333] Examples of cyclic carbonate solvents include ethylene carbonate, propylene carbonate, and butylene carbonate.

[0334] The chain ether solvent may, for example, be 1,2-dimethoxyethane.

[0335] Examples of the cyclic ether solvent include tetrahydrofuran, 2-methyltetrahydrofuran, sulfolane, and 1,3-dioxolane.

[0336] Examples of the chain ester solvent include methyl formate, methyl acetate, and methyl propionate.

[0337] Examples of the cyclic ester solvent include γ-butyrolactone and γ-valerolactone.

[0338] In one embodiment, the non-aqueous solvent preferably includes a combination of a cyclic carbonate and a chain carbonate.

[0339] The supporting electrolytes may be used alone or in combination of two or more.

[0340] The supporting electrolyte may be, for example, a lithium salt. The lithium salt may be, for example, LiPF ６ , LiAsF ６ , LiBF ４ , LiSbF ６ , LiAlCl ４ , LiClO ４ , C.F. ３ SO ３ Li, C ４ F ９ SO ３ Li, CF ３ COOLi, (CF ３ CO) ２ NLi, (CF ３ SO ２ ) ２ NLi, (C ２ F ５ SO ２ In one embodiment, the supporting electrolyte is preferably LiPF ６ , LiClO ４ , C.F. ３ SO ３ Examples of such metals include Li.

[0341] In one embodiment, the non-aqueous electrolyte may optionally contain a film-forming agent. The film-forming agents may be used alone or in combination of two or more.

[0342] Examples of the film-forming agent include carbonates, alkene sulfides, sultones, and acid anhydrides.

[0343] Examples of carbonates include vinylene carbonate, vinyl ethylene carbonate, vinyl ethyl carbonate, methyl phenyl carbonate, fluoroethylene carbonate, and difluoroethylene carbonate.

[0344] Examples of the alkene sulfide include ethylene sulfide and propylene sulfide.

[0345] Examples of the sultone include 1,3-propane sultone and 1,4-butane sultone.

[0346] Examples of the acid anhydride include maleic anhydride and succinic anhydride.

[0347] In one embodiment, the mass % content (film-forming agent / electrolyte solution) is preferably 10 mass % or less, more preferably 8 mass % or less, even more preferably 5 mass % or less, and particularly preferably 2 mass % or less.

[0348] Examples of the form (electricity storage device) include a cylindrical type in which a sheet electrode and a separator are spirally wound, a cylindrical type with an inside-out structure in which a pellet electrode and a separator are combined, and a coin type in which a pellet electrode and a separator are stacked.

[0349] Examples of the manufacturing method (electricity storage device) include the method described in JP 2013-089437 A.

[0350] Examples of applications (electricity storage devices) include batteries, non-aqueous secondary batteries, lithium ion batteries, and sodium ion batteries.

[0351] The present invention will be described in detail 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 by the claims. Unless otherwise specified below, numerical values ​​such as parts and % are based on mass.

[0352] Example 1: 575 g of ion-exchanged water, 63 g (0.63 mol) of dimethylacrylamide, 11 g (0.13 mol) of an 80% aqueous acrylic acid solution, and 5.7 g (0.08 mol) of acrylamide were placed in a reaction apparatus equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube. After removing oxygen from the reaction system by passing nitrogen gas through the reaction system, the temperature was raised to 55°C. 0.66 g of 2,2'-azobis-2-amidinopropane dihydrochloride as an initiator and 6.6 g of ion-exchanged water were added, and the temperature was raised to 80°C and the reaction was carried out for 3 hours. After completion of the reaction, 10.0 g (0.12 mol) of a 48% aqueous sodium hydroxide solution was added to obtain an aqueous solution for an electricity storage device.

[0353] Unless otherwise stated, the following examples were carried out in the same manner as above, except for the changes shown in the table.

[0354] DMAA: Dimethylacrylamide AA: Acrylic acid AANa: Sodium acrylate AM: Acrylamide SMAS: Sodium methallylsulfonate 2MTA: 2-Methoxyethyl acrylate

[0355] The measurement conditions (B-type viscosity) were as follows: Non-volatile content: 3% by mass Measurement temperature: 25°C B-type viscometer: Toki Sangyo Co., Ltd., product name "B-type viscometer model TVB-10" Viscosity less than 100 mPa·s: No. 1 rotor, rotation speed 60 rpm Viscosity 100 mPa·s to 1000 mPa·s: No. 2 rotor, rotation speed 30 rpm Viscosity 1000 mPa·s to 2500 mPa·s: No. 2 rotor, rotation speed 12 rpm Viscosity over 2500 mPa·s to 10000 mPa·s: No. 3 rotor, rotation speed 12 rpm

[0356] <Evaluation of the Performance of Electricity Storage Device Electrodes> (1-1) Production of Electricity Storage Device Electrode Slurry Using a commercially available planetary centrifugal mixer (product name "Awatori Rentaro", manufactured by Thinky Corporation), 7 parts by mass of the electricity storage device aqueous solution, calculated as nonvolatile content, 50 parts by mass of silicon monoxide particles having a D50 of 5 μm, and 50 parts by mass of natural graphite (manufactured by Ito Graphite Industries Co., Ltd., product name "Z-5F") were mixed in a container designed specifically for the mixer. Ion-exchanged water was added thereto so that the nonvolatile content concentration was 40%, and the container was set in the mixer. Next, the mixture was kneaded at 2000 rpm for 10 minutes and then degassed for 1 minute to obtain an electricity storage device electrode slurry.

[0357] (1-2) Production of an Electrode for a Power Storage Device The electrode slurry for a power storage device was uniformly applied to the surface of a current collector made of copper foil by a doctor blade method so that the film thickness after drying would be 25 μm, and the resulting film was dried at 80° C. for 30 minutes and then heat-treated at 100° C. for 60 minutes to obtain an electrode. After that, the density of the film (electrode active material layer) was 1.2 g / cm ３ The electrode was obtained by pressing the electrode using a roll press machine.

[0358] (1-3) Production of an Electricity Storage Device In an argon-substituted glove box, the above electrode was punched out to a diameter of 16 mm and placed on a two-electrode coin cell (manufactured by Hosen Co., Ltd., trade name "HS Flat Cell"). Next, a separator made of a polypropylene porous membrane punched out to a diameter of 24 mm (manufactured by CS TECH CO., LTD., trade name "Selio P2010") was placed on top, and 500 μL of electrolyte was poured in to prevent air from entering. After that, a commercially available metallic lithium foil punched out to a diameter of 16 mm was placed on top, and the exterior body of the two-electrode coin cell was sealed with screws to assemble an electricity storage device (lithium half cell). The electrolyte used here was a solution of LiPF in a solvent of ethylene carbonate / dimethyl carbonate = 3 / 7 (volume ratio). ６ It is a solution in which the above is dissolved at a concentration of 1 mol / L.

[0359] The electricity storage device having the electricity storage device electrode functioned without any problems.

[0360] <Adhesion (after electrode production)> A test piece measuring 2 cm wide x 10 cm long was cut from the resulting electrode and fixed with the coating surface facing up. Next, a 15 mm wide adhesive tape ("Cellotape (registered trademark)" manufactured by Nichiban Co., Ltd.) (specified in JIS Z1522) was applied to the electrode layer surface of the test piece while pressing it, and the adhesive tape was then peeled from one end of the test piece in a 180° direction at a rate of 30 mm / min using a tensile tester ("AGX-1kNNVD" manufactured by Shimadzu Corporation) at 25°C, and the stress was measured when the adhesive tape was peeled off in a 180° direction at a rate of 30 mm / min. The measurement was performed five times, converted into a value per 15 mm width, and the average value was calculated as the peel strength.

[0361] <Adhesion (after electrolyte impregnation)> The test piece was placed in a Lamizip ("Lamizip AL-12 (registered trademark)" AS ONE Corporation), and an amount of electrolyte (EC / DMC / EMC = 1 / 1 / 1 (v / v)) was poured into it so that the test piece was fully immersed. The Lamizip was sealed by heat sealing and kept warm at 80°C for 24 hours in a dryer. The test piece was taken out, and the surface was lightly washed with DMC and then lightly wiped, and the peel strength was calculated by the method described above.

[0362] <Evaluation of the Performance of Electricity Storage Device Separator> (2-1) Production of Electricity Storage Device Separator Slurry Five parts by mass, calculated as nonvolatile content, of the above-described electricity storage device aqueous solution and 113 parts by mass of water were stirred and mixed, and 100 parts by mass of boehmite (average particle size 0.8 μm) as non-conductive particles were added, followed by dispersion and stirring for 60 minutes at 15,000 rpm using a homogenizer (T25 digital ULTRA-TURRAX manufactured by IKA Corporation). Ion-exchanged water was further added to adjust the viscosity, thereby producing an electricity storage device separator slurry.

[0363] (2-2) Separator Production: Lamination of Separator Slurry Layer (Coating Layer) A single-layer polyethylene separator substrate (PE substrate) produced by a wet method was prepared, measuring 250 mm in width, 200 mm in length, and 6 μm in thickness. The electricity storage device separator slurry was applied to one side of the separator using a gravure coater so that the thickness after drying was 3.0 μm, and then dried to obtain an electricity storage device separator.

[0364] (2-3) Production of Electricity Storage Device An electricity storage device was produced in the same manner as in (1-3) Production of Electricity Storage Device, except that the separator was changed to the separator produced above.

[0365] The electricity storage device having the electricity storage device separator functioned without any problems.

[0366] Reference Production Example 1: A reaction apparatus equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube was charged with 1,200 g of ion-exchanged water, 100 g (0.70 mol) of a 50% aqueous acrylamide solution, 63.4 g (0.70 mol) of 80% acrylic acid, 69.8 g (0.60 mol) of 2-hydroxyethyl acrylate, and 0.32 g (0.0020 mol) of sodium methallylsulfonate. After removing oxygen from the reaction system by passing nitrogen gas through the reaction system, the temperature was raised to 55° C. Then, 1.7 g of 2,2′-azobis-2-amidinopropane dihydrochloride (manufactured by Nippoh Chemical Co., Ltd., product name "NC-32") and 15 g of ion-exchanged water were added, and the temperature was raised to 80° C., followed by a reaction for 3 hours. Thereafter, 52.7 g (0.63 mol) of a 48% aqueous solution of sodium hydroxide was added as a neutralizing agent and stirred, and ion-exchanged water was added to adjust the solid content to 13%, to obtain an aqueous solution containing water-soluble polyacrylamide. The pH of this solution at 25° C. was 6.0.

[0367] <Evaluation of the Electrolyte for Electricity Storage Device> Reference Example 1 The aqueous solutions obtained in Example 8 and Reference Production Example 1 were uniformly mixed so that the solid weight ratio was 7:3, and the resulting aqueous solution for electricity storage device was dried at 80°C for 1.5 hours and then further dried at 120°C for 1 hour to prepare a film. The prepared film was then washed with an electrolyte solution (1 mol / L LiPF ６ The sample was immersed in a solution of ethylene carbonate:ethyl methyl carbonate:dimethyl carbonate = 1:1:1 (volume ratio) at 60°C for 1 hour, and the swelling ratio was measured. Swelling ratio = [(mass after swelling - mass before swelling) / mass before swelling] x 100

[0368] Unless otherwise stated, the following examples were carried out in the same manner as above, except for the changes shown in the table. SBR: Styrene butadiene rubber CMC: Carboxymethyl cellulose

Claims

1. An aqueous solution for an electricity storage device, the aqueous solution for the electricity storage device comprising a water-soluble polymer, the water-soluble polymer comprising 20 mol % to 95 mol % of alkyl(meth)acrylamide units, 0.1 mol % to 40 mol % of unsaturated carboxylic acid units, and 2.5 mol % to 79.9 mol % of unsaturated carboxylate units, and having a Brookfield viscosity (25°C, non-volatile content 3% by mass) of 155 mPa·s to 10,000 mPa·s.

2. An electricity storage device slurry, the electricity storage device slurry comprising a water-soluble polymer and water, the water-soluble polymer comprising 20 mol % to 95 mol % of alkyl(meth)acrylamide units, 0.1 mol % to 40 mol % of unsaturated carboxylic acid units, and 2.5 mol % to 79.9 mol % of unsaturated carboxylate units, and the water-soluble polymer has a Brookfield viscosity (25°C, non-volatile content 3% by mass) of 155 mPa·s to 10,000 mPa·s.

3. The electric storage device slurry according to claim 2, which contains an electrode active material.

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

5. An electric storage device electrode having a current collector on which is disposed a dried product of the electric storage device slurry according to claim 2 or 3.

6. An electricity storage device separator having the dried electricity storage device slurry according to claim 2 or 4 on a substrate.

7. An electric storage device separator / electrode laminate having the dried electric storage device slurry according to claim 2 or 4 on the active material side of an electrode.

8. An electricity storage device electrolyte, which is a gel of the electricity storage device aqueous solution according to claim 1.

9. An electricity storage device comprising the electricity storage device electrode according to claim 5.

10. An electricity storage device comprising the electricity storage device separator according to claim 6.

11. An electricity storage device comprising the electricity storage device separator / electrode laminate of claim 7.

12. An electricity storage device comprising the electricity storage device electrolyte according to claim 8.

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