JP2021144868A - Slurry, method for manufacturing the same, separator for nonaqueous electrolyte battery, and nonaqueous electrolyte battery - Google Patents

Abstract

To provide slurry suitably used for manufacturing a separator for a nonaqueous electrolyte battery, which is superior in the stability of the shape at a temperature of about 160°C.SOLUTION: A slurry comprises: an inorganic filler containing at least one kind selected from a group consisting of alumina, barium sulfate, boehmite, calcium carbonate, calcium phosphate, calcium sulfate, calcium oxide, magnesium hydroxide, magnesium carbonate, magnesium oxide, magnesium sulfate, kaolin, talc, titanium dioxide, calcium fluoride, lithium fluoride, zeolite, molybdenum sulfide and mica; a solvent; and a polyamide resin having, in its main chain, such a structure that a hydrogen atom binding to a nitrogen atom of an amide group is substituted with another group, and including, in its side chain, at least one anion selected from a group consisting of a phenoxide anion, a carboxylate anion and a sulfonate anion, and a counter cation to the anion.SELECTED DRAWING: None

Description

The present invention relates to slurries, methods for producing slurries, separators for non-aqueous electrolyte batteries and non-aqueous electrolyte batteries.

In recent years, non-aqueous electrolyte batteries such as lithium-ion secondary batteries have been widely used as power sources for portable electronic devices and transportation devices, and in particular, because they are lightweight and have a high energy density, they can be used as high-output power sources for driving vehicles. Demand is expected to grow.

The non-aqueous electrolyte battery is arranged in the cell so that the positive electrode and the negative electrode face each other, and has an ion-permeable separator between the two electrodes in order to prevent a short circuit between the two electrodes. As the separator, a porous film made of polyolefin is preferably used. The porous polyolefin membrane is excellent in electrical insulation, ion permeability, electrolytic solution resistance and oxidation resistance. Further, the porous polyolefin membrane can block the current and suppress an excessive temperature rise by closing the pores at a temperature of about 100 to 150 ° C., which is assumed at the time of abnormal temperature rise. However, if the temperature continues to rise even after the pores are closed for some reason, the porous polyolefin membrane may shrink, causing a short circuit between the electrodes and causing the non-aqueous electrolyte battery to ignite.

So far, as a separator that can constitute a non-aqueous electrolyte battery having excellent safety, a resin porous film containing a thermoplastic resin as a main component and having a heat shrinkage rate of 10% or more at 150 ° C. and heat-resistant fine particles have been used. Separator for non-aqueous electrolyte battery having a heat-resistant porous layer containing (see, for example, Patent Document 1), separator for non-aqueous electrolyte secondary battery in which a porous film of a water-soluble polymer and a porous film of polyolefin are laminated. (See, for example, Patent Document 2), a separator for a lithium ion battery (for example, a separator for a lithium ion battery) having a polymer microporous film and a coating layer formed of a slurry composition containing inorganic fine particles, a water-soluble polymer, water-insoluble organic fine particles, and water. Patent Document 3), a separator for a lithium ion battery having a layer containing a heat-resistant nitrogen-containing aromatic polymer and a ceramic powder (see, for example, Patent Document 4) have been proposed.

Japanese Unexamined Patent Publication No. 2008-123996 JP-A-2009-224343 Japanese Unexamined Patent Publication No. 2016-25093 Japanese Unexamined Patent Publication No. 2000-30686

Although the techniques described in Patent Documents 1 to 4 are excellent in shape stability at a temperature of about 100 to 150 ° C., they are suitable for shape stability under high temperature conditions of about 160 ° C., which may occur in high-power power supply applications required in recent years. However, there were still issues. Therefore, an object of the present invention is to provide a slurry that is suitably used for producing a separator for a non-aqueous electrolyte battery having excellent shape stability at a temperature of about 160 ° C.

In order to solve the above problems, the present invention
The inorganic filler contains an inorganic filler, a solvent and a water-soluble polymer, and the inorganic filler is alumina, barium sulfate, boehmite, calcium carbonate, calcium phosphate, calcium sulfate, calcium oxide, magnesium hydroxide, magnesium carbonate, magnesium oxide, magnesium sulfate, kaolin, One or more selected from the group consisting of talc, titanium dioxide, calcium fluoride, lithium fluoride, zeolite, molybdenum sulfide and mica, and the water-soluble polymer is (a) a polyamide resin and (a) a polyamide resin. However, at least one selected from the group consisting of a phenoxide anion, a carboxylate anion and a sulfonate anion, having a structure in which a hydrogen atom bonded to a nitrogen atom of an amide group is substituted with another group in the main chain. A slurry which is a resin containing an anion and a countercation for the anion in a side chain.

The present invention also has a porous membrane (I) containing a polyolefin resin and a particle layer (II) containing an inorganic filler, a water-soluble polymer and a water-insoluble polymer.
The water-soluble polymer is (a) a polyamide resin, and (a) the polyamide resin has a structure in which a hydrogen atom bonded to a nitrogen atom of an amide group is substituted with another group in the main chain, and phenoxide. A separator for a non-aqueous electrolyte battery, which is a resin containing at least one anion selected from the group consisting of an anion, a carboxylate anion, and a sulfonic acid anion and a counter cation with respect to the anion in a side chain, and is 1 at 160 ° C. A separator for a non-aqueous electrolyte battery having a heat shrinkage rate of 10% or less when heated for an hour.

By using the slurry and separator of the present invention, it is possible to provide a separator having excellent shape stability at a temperature of about 160 ° C.

<Slurry>
The slurry of the present invention contains an inorganic filler, a solvent and a water-soluble polymer, and the inorganic filler is alumina, barium sulfate, boehmite, calcium carbonate, calcium phosphate, calcium sulfate, calcium oxide, magnesium hydroxide, magnesium carbonate, magnesium oxide. , Magnesium sulfate, kaolin, talc, titanium dioxide, calcium fluoride, lithium fluoride, zeolite, molybdenum sulfide and mica, and the water-soluble polymer is (a) polyamide resin. , (A) From the group consisting of a phenoxide anion, a carboxylate anion and a sulfonic acid anion, in which the polyamide resin has a structure in which the hydrogen atom bonded to the nitrogen atom of the amide group is substituted with another group in the main chain. A slurry which is a resin containing at least one selected anion and a counter cation for the anion in a side chain.

The inorganic filler has the effect of improving the shape stability of the separator when it is heated when the separator is produced.

Since the inorganic filler has insulating properties, alumina, barium sulfate, boehmite, calcium carbonate, calcium phosphate, calcium sulfate, calcium oxide, magnesium hydroxide, magnesium carbonate, magnesium oxide, magnesium sulfate, kaolin, talc, titanium dioxide, and foot One or more selected from the group consisting of calcium phosphate, lithium fluoride, zeolite, molybdenum sulfide and mica. Among these, an inorganic filler selected from alumina and barium sulfate is preferable. Alumina is more preferable from the viewpoint that the surface is highly hydrophilic and the inorganic filler and the water-soluble polymer can be firmly bonded with a small amount of addition.

The average particle size of the inorganic filler is preferably 0.1 μm or more. When the average particle size is 0.1 μm or more, the specific surface area of the inorganic filler can be appropriately suppressed and the surface adsorbed water can be reduced, so that the water content as a separator can be reduced and the battery characteristics can be further improved. Is possible. On the other hand, the average particle size of the inorganic filler is preferably 2.0 μm or less, more preferably 1.0 μm or less. When the average particle size is 2.0 μm or less, the film thickness of the particle layer (II) described later can be easily adjusted to a desired range described later.

The average particle size referred to here is a flow rate of a liquid obtained by adding an inorganic filler to water using a laser scattering particle size distribution meter (“MT3300EXII” manufactured by Microtrac Bell Co., Ltd. (formerly Nikkiso Co., Ltd.)). It refers to a particle size (D50) of 50% in a volume-based integrated fraction measured within 10 minutes after being circulated for 3 minutes while irradiating ultrasonic waves under the conditions of 45% and an output of 25 W.

The slurry of the present invention contains a solvent. Examples of the solvent include alcohols such as methanol, ethanol and isopropanol, water, acetone, toluene, xylene, hexane, N-methylpyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide and the like, and water is preferable.

The water-soluble polymer contained in the slurry of the present invention is (a) a polyamide resin described later. The slurry of the present invention preferably contains 0.4 to 5.0 parts by mass of the (a) polyamide resin with respect to 100 parts by mass of the inorganic filler. (A) By setting the content of the polyamide resin to 0.4 parts by mass or more, the inorganic filler can be firmly bound and the shape stability of the separator during heating can be further improved. The content of the polyamide resin (a) is more preferably 1.0 part by mass or more. On the other hand, by setting the content of the polyamide resin (a) to 5.0 parts by mass or less, clogging of the porous membrane (I) described later can be reduced and an increase in the air permeation resistance of the separator can be suppressed. can.

Here, the air permeability resistance means how much the air permeability of the separator having the porous membrane (I) and the particle layer (II) described later increases with respect to the air permeability of only the porous membrane (I). It is a value indicating whether or not it is. The air permeability is the time required for a certain amount of air to pass through a certain area of a membrane under a constant pressure, and this value determines the porosity of the membrane.

The slurry of the present invention preferably further contains a water-insoluble polymer. In this case, the content of the water-insoluble polymer is preferably 0.5 to 5.0 parts by mass with respect to 100 parts by mass of the inorganic filler. By setting the content of the water-insoluble polymer to 0.5 parts by mass or more, the particle layer (II) described later is strongly bonded to the porous film (I) even during heating, so that the shape stability of the separator can be improved. It can be improved further. The content of the water-insoluble polymer is more preferably 1.5 parts by mass or more with respect to 100 parts by mass of the inorganic filler. On the other hand, by setting the content of the water-insoluble polymer to 5.0 parts by mass or less, clogging of the porous membrane (I) described later can be reduced and an increase in the air permeation resistance of the separator can be suppressed. can. Specific examples of the water-insoluble polymer preferably used in the slurry of the present invention will be shown in the description of "Separator for non-aqueous electrolyte battery" described later.

The slurry of the present invention preferably further contains one or more polymers selected from the group consisting of cellulose ether, polyvinyl alcohol and sodium alginate. By including these polymers, the viscosity of the slurry can be increased, and the dispersion of the inorganic filler in the slurry can be kept more stable. Among them, the cellulose ether is preferably carboxylmethyl cellulose, which is less deteriorated by long-term use and has excellent chemical stability.

<Separator for non-aqueous electrolyte batteries>
The separator for a non-aqueous electrolyte battery of the present invention has a porous film (I) containing a polyolefin resin and a particle layer (II) containing an inorganic filler, a water-soluble polymer and a water-insoluble polymer. It is preferable to have the particle layer (II) on one side or both sides of the porous membrane (I). Here, having the particle layer (II) on one side of the porous film (I) means that the particle layer (II) is formed on one surface of the porous film (I). Further, having the particle layers (II) on both sides of the porous film (I) means that the particle layers (II) are formed on both surfaces of the porous film (I).

1. 1. Porous membrane (I)
The porous membrane (I) in the present invention contains a polyolefin resin. Since the porous membrane (I) contains a polyolefin resin, it has a function of blocking the current by closing the pores when the temperature rises abnormally and preventing a short circuit between the two electrodes in the non-aqueous electrolyte battery.

Examples of the polyolefin resin include polyethylene resin and polypropylene resin. Two or more of these may be included. Among these, polyethylene resin is preferable because it has higher electrical insulating property, ion permeability, and pore closing effect. The porous membrane (I) may contain other resins as well as the polyolefin resin.

The melting point (softening point) of the resin constituting the porous membrane (I) is preferably 150 ° C. or lower, preferably 140 ° C. or lower, from the viewpoint of the function of closing the pores (pore closing function) when the temperature rises abnormally during the charge / discharge reaction. More preferably, 130 ° C. or lower is further preferable. On the other hand, from the viewpoint of suppressing pore blockage in the normal state, the melting point (softening point) is preferably 70 ° C. or higher, more preferably 80 ° C. or higher, and even more preferably 100 ° C. or higher. Here, the melting point (softening point) can be determined by differential scanning calorimetry (DSC) based on JIS K7121: 2012.

The weight average molecular weight of the polyolefin resin is preferably 300,000 or more from the viewpoint of process workability and mechanical strength (for example, tensile strength, elastic modulus, elongation, piercing strength) that can withstand various external pressures generated during rotation with the electrode. , More preferably 400,000 or more, still more preferably 500,000 or more.

The pore size of the porous membrane (I) is preferably 0.01 μm or more, more preferably 0.05 μm or more, still more preferably 0.1 μm or more, from the viewpoint of ensuring ion permeability and suppressing deterioration of battery characteristics. On the other hand, from the viewpoint of increasing the response of the hole closing function to the temperature, 1.0 μm or less is preferable, 0.5 μm or less is more preferable, and 0.3 μm or less is further preferable.

The air permeability of the porous membrane (I) is preferably 500 s / 100 ccAir or less, more preferably 400 s / 100 ccAir or less, still more preferably 300 s / 100 ccAir, from the viewpoint of ensuring ion permeability and suppressing deterioration of battery characteristics. It is preferably 50 s / 100 cc Air or more, more preferably 70 s / 100 cc Air or more, and further preferably 100 s / 100 cc Air or more in order to obtain sufficient insulating property in the battery. Here, the air permeability can be determined by a Garley type densometer B type manufactured by Tester Sangyo Co., Ltd. based on JIS P8117: 2009.

2. Particle layer (II)
The particle layer (II) has a shape in which most of the inorganic filler is bonded with a trace amount of resin, and has a function of improving the shape stability of the separator during heating. The particle layer (II) contains an inorganic filler, a water-soluble polymer and a water-insoluble polymer. The water-soluble polymer is (a) a polyamide resin, and (a) the polyamide resin has a structure in which a hydrogen atom bonded to a nitrogen atom of an amide group is substituted with another group in the main chain, and a phenoxide anion. , A resin containing at least one anion selected from the group consisting of a carboxylate anion and a sulfonic acid anion and a counter cation to the anion in the side chain. Other components may be contained as required.

The particle layer (II) is formed by preparing a slurry containing an inorganic filler, a water-soluble polymer and a water-insoluble polymer and a solvent as essential components, and coating and drying the slurry on the porous layer (I). be able to.

The details of each component will be described below.

[1] Inorganic Filler The particle layer (II) has an effect of improving the shape stability of the separator during heating by containing the inorganic filler.

Examples of the inorganic filler include an inorganic filler generally called a filler. For example, alumina, barium sulfate, boehmite, calcium carbonate, calcium phosphate, calcium sulfate, calcium oxide, magnesium hydroxide, magnesium carbonate, magnesium oxide, magnesium sulfate, amorphous silica, crystalline glass filler, kaolin, talc, titanium dioxide, Examples thereof include silica-alumina composite oxide particles, calcium fluoride, lithium fluoride, zeolite, molybdenum sulfide, and mica. Two or more of these may be included. Among these, alumina or barium sulfate is preferable. Alumina is more preferable from the viewpoint that the surface is highly hydrophilic and the inorganic filler and the water-soluble polymer can be firmly bonded with a small amount of addition.

The average particle size of the inorganic filler is preferably 0.1 μm or more. When the average particle size is 0.1 μm or more, the specific surface area of the inorganic filler can be appropriately suppressed and the surface adsorbed water can be reduced, so that the water content as a separator can be reduced and the battery characteristics can be further improved. Is possible. On the other hand, the average particle size of the inorganic filler is preferably 2.0 μm or less, more preferably 1.0 μm or less. When the average particle size is 2.0 μm or less, the film thickness of the particle layer (II) can be easily adjusted to a desired range described later.

[2] Water-soluble polymer The water-soluble polymer has the effect of improving the shape stability of the separator during heating by binding the inorganic fillers to each other.

The (a) polyamide resin used in the present invention has a structure in which a hydrogen atom bonded to a nitrogen atom of an amide group is substituted with another group in the main chain, and a phenoxide anion, a carboxylate anion and a sulfonic acid anion. The side chain contains at least one anion selected from the group consisting of the above anion and a counter cation with respect to the anion. (A) The polyamide resin has at least one anion selected from the group consisting of a phenoxide anion, a carboxylate anion, and a sulfonic acid anion, and a counter cation to the anion in the side chain, so that the polyamide resin becomes soluble in water. Excellent.

Having the anion and its countercation in the side chain means, in other words, having the structure of at least one salt selected from the group consisting of phenol salts, carboxylates and sulfonates in the side chain. Can be done.

Here, the main chain is a linear molecular chain that serves as a trunk in a polymer constituting a resin, and mainly refers to a chain in which carbon atoms are connected. The side chain refers to a part other than the main chain. When a benzene ring is contained in the polymer structure, the part contained in the main chain in the benzene ring is the portion constituting the linear molecular chain at the shortest distance, and the portion thereof is the side chain.

(A) A structure containing at least one anion selected from the group consisting of a phenoxide anion, a carboxylate anion and a sulfonic acid anion contained in a polyamide resin and a counter cation to the anion in a side chain has a rigid main chain structure. Therefore, the heat resistance can be improved.

The fact that the hydrogen atom bonded to the nitrogen atom of the amide group has a structure in which the hydrogen atom is substituted with another group in the main chain is paraphrased as follows. Normally, the amide group as a repeating structure in the polyamide resin is represented by -CO-NH-, but in the (a) polyamide resin used in the present invention, the hydrogen atom (H) in the above structure is any other option. Including those substituted with the group of.

(A) The polyamide resin has a structure in which the hydrogen atom bonded to the nitrogen atom of the amide group is replaced with another group in the main chain, so that the number of hydrogen bonding sites is smaller than that of the normal polyamide resin. Therefore, it is considered that the intermolecular interaction between the polyamide resins becomes small and the solubility in a solvent, particularly water, is improved. In addition, since the interaction between molecules is small, (a) when a resin composition containing a polyamide resin is applied to form a thick film, the resin component may rapidly shrink even if the solvent is volatilized by prebaking. It is considered that cracks are unlikely to occur.

Further, although the detailed mechanism is unknown, (a) the polyamide resin has a small electrochemical deterioration, so that when it is used as a separator for a non-aqueous electrolyte battery, the initial efficiency of the battery is improved.

The (a) polyamide resin used in the present invention is preferably a resin containing a structure represented by the following general formula (1) as a repeating unit.

R ¹ represents an organic group having 2 to 30 carbon atoms. R ² represents an organic group having 3 to 30 carbon atoms. R ³ and R ⁴ each independently represent a halogen atom or an organic group having 1 to 10 carbon atoms. At least one of ^{R 3} and R ^{4 may be connected to a part of R 1} to form an annular structure. Further, R ³ and R ⁴ may be directly bonded to form an annular structure. R ^5- and R ^6- each independently represent at least one anion selected from the group consisting of phenoxide anions, carboxylate anions and sulfonic acid anions. M ⁺ represents the counter cation to the anion. a ₁ and a ₂ are integers from 0 to 4, and a ₁ + a ₂ > 0.

-R ¹ (-R ^5- M ⁺ ) a ₁ -is a diamine residue. From the viewpoint of solubility in water, R ¹ is preferably a hydrocarbon group, more preferably a hydrocarbon group having 2 to 15 carbon atoms, and further preferably a hydrocarbon group having 2 to 10 carbon atoms. preferable. Further, from the viewpoint of the initial efficiency of the battery when used as a separator for a non-aqueous electrolyte battery, R ¹ is preferably an aliphatic group.

R ^5- is preferably a carboxylate anion from the viewpoint of adhesiveness to the substrate. a ₁ is preferably 0 to 2.

Specific examples of the R ¹ portion of the diamine giving −R ¹ (−R ^5-5 M ⁺ ) a ₁ − include benzidine, diaminodiphenyl ether, diaminodiphenylmethane, diaminodiphenylsulfone, diaminodiphenylsulfide, bis (4-aminophenoxy). Benzene, bis (3-aminophenoxy) benzene, phenylenediamine, naphthalenediamine, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, 4,4'- Bis (4-aminophenoxy) biphenyl, bis [4- (4-aminophenoxy) phenyl] ether, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-diethyl-4,4'- Diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-diethyl-4,4'-diaminobiphenyl, 2,2', 3,3'-tetramethyl-4,4' -Diaminobiphenyl, 3,3', 5,5'-tetramethyl-4,4'-diaminobiphenyl, 2,2'-di (trifluoromethyl) -4,4'-diaminobiphenyl and their aromatic rings Residues of hydrogenated compounds, residues of ethylenediamine, propanediamine, butanediamine, cyclobutanediamine, cyclopentanediamine, decanediamine, cyclononandimine, hexamethylenediamine and the like can be mentioned.

Further, in order to improve the adhesion to the substrate, ₁ ^{to 10 mol% of −R 1} (−R ^5-5 M ⁺ ) a 1 − may be a residue of a diamine containing a siloxane bond. Specific diamines that give residues of diamines containing a siloxane bond include 1,3-bis (3-aminopropyl) tetramethyldisiloxane.

Specific examples of R ³ and R ⁴ include fluoro group, chloro group, bromo group, iodo group, methyl group, ethyl group, propyl group, butyl group, isopropyl group, isobutyl group, t-butyl group, isopentyl group and hexyl. Examples thereof include a group, a trifluoromethyl group, a pentafluoroethyl group, a cyclobutyl group, a cyclohexyl group, a cyclopentyl group, a phenyl group and a naphthyl group.

Further, at least one of ^{R 3} and R ^{4 may be connected to a part of R 1} to form an annular structure. Specific examples of -N (R ³ ) -R ¹ (-R ^5- M ⁺ ) a ₁ -N (R ⁴ )-in that case include a residue of bipiperidine when _{a 1 is 0.} Be done. When a ₁ is an integer of 1 to 4, residues of 3,3'-bipiperidin-4,4'-disodium dicarboxylic acid and the like can be mentioned.

Further, R ³ and R ⁴ may be directly bonded to form an annular structure. As a specific example of -N (R ³ ) -R ¹ (-R ^5- M ⁺ ) a ₁ -N (R ⁴ _{)-in that case, when a 1} is 0, piperazine, homopiperazin, and methyl Examples thereof include residues of piperazine and dimethylpiperazine. When a ₁ is an integer of 1 to 4, residues of sodium piperazine-2-carboxylate, sodium homopiperazin-2-carboxylate, and the like can be mentioned.

^{More preferable -N (R 3} ) -R ¹ (-R ^5- M ⁺ ) a _1- N (R) from the viewpoint of crack resistance and initial efficiency of the battery when used as a separator for a non-aqueous electrolyte battery. ⁴ )-Examples of-have the following structure.

R ^{7 to} R ¹⁰ are independently methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group or t-butyl group. R ^11- , R ^13- , R ^15- , R ^17- , R ^19- and R ^21- each independently represent at least one anion selected from the group consisting of carboxylate anions and sulfonic acid anions. M ⁺ represents the counter cation to the anion. R ¹² , R ¹⁴ , R ¹⁶ , R ¹⁸ , R ²⁰ and R ²² each independently represent a hydrocarbon group having 1 to 4 carbon atoms. a ₃ represents an integer of 1 to 6. a ₄ , a ₆ , a ₈ , a ₁₀ , a ₁₂ and a ₁₄ each independently represent an integer of _{0 to 4, and when a 2} = 0, they represent an integer of 1 to 4. a ₅ , a ₇ , a ₉ , a ₁₁ , a ₁₃ and a ₁₅ each independently represent an integer of 0-4. a ₄ + a ₅ , a ₆ + a ₇ , a ₁₂ + a ₁₃ and a ₁₄ + a ₁₅ each independently represent an integer of 0-4. a ₈ + a ₉ represents an integer from 0 to 5. a ₁₀ + a ₁₁ represents an integer from 0 to 6.

-N (R ³ ) -R ¹ (-R ^5- M ⁺ ) a ₁ -N (R ⁴ )-is more preferably having the following structure from the viewpoint of higher crack resistance.

-R ² (-R ^6- M ⁺ ) a _2- is a residue of a dicarboxylic acid, a tricarboxylic acid, a tetracarboxylic acid, or the like. From the viewpoint of the solubility of the aqueous solution, R ² is preferably a hydrocarbon group, more preferably a hydrocarbon group having 2 to 15 carbon atoms, and further preferably a hydrocarbon group having 2 to 10 carbon atoms. preferable. Further, from the viewpoint of the initial efficiency of the battery when used as a separator for a non-aqueous electrolyte battery, R ² is preferably an aliphatic group.

R ^6- is preferably a carboxylate anion from the viewpoint of adhesiveness to the substrate. a ₂ is preferably an integer of 0 to 2 from the viewpoint of crack resistance.

Examples of R ² _{when a 2} is 0 include a residue of a dicarboxylic acid. Preferably, terephthalic acid, isophthalic acid, diphenyl ether dicarboxylic acid, diphenylsulfonedicarboxylic acid, diphenylmethanedicarboxylic acid, biphenyldicarboxylic acid, 2,2'-bis (carboxyphenyl) propane, 2,2'-bis (carboxyphenyl) hexafluoro Residues of propane, adipic acid, fumaric acid, succinic acid, oxalic acid, cyclohexane-decarboxylic acid, cyclopentanedicarboxylic acid and the like can be mentioned.

Specific examples of -R ² (-R ^6- M ⁺ )-when a ₂ is 1 include tricarboxylic acids such as trimellitic acid, trimesic acid, diphenyl ether tricarboxylic acid, and biphenyl tricarboxylic acid, in addition to dicarboxylic acid residues. Examples include acid residues.

Specific examples of −R ² (−R ⁶⁻ M ⁺ ) ₂ − when a ₂ is 2 include a residue of dicarboxylic acid, a residue of tricarboxylic acid, and a residue of tetracarboxylic acid. More preferably, pyromellitic acid, biphenyltetracarboxylic acid, benzophenone tetracarboxylic acid, 2,2-bis (dicarboxyphenyl) hexafluoropropane, 1,1-bis (dicarboxyphenyl) ethane, bis (dicarboxyphenyl). Residues of aromatic tetracarboxylic acids such as methane, bis (dicarboxyphenyl) sulfone, bis (dicarboxyphenyl) ether, naphthalenetetracarboxylic acid, pyridinetetracarboxylic acid, perylenetetracarboxylic acid, cyclobutanetetracarboxylic acid, cyclo Examples thereof include residues of aliphatic tetracarboxylic acids such as pentantetracarboxylic acid, cyclohexanetetracarboxylic acid, bicycloheptanetetracarboxylic acid, adamatanetetracarboxylic acid and butanetetracarboxylic acid.

Crack resistance, in view of the initial efficiency of the battery when used in a separator for a nonaqueous electrolyte ^{battery, -R 2 (R 6- M +} ) a 2 - and more preferably the following structure as a specific example of R ² parts of Can be mentioned.

The above is the structure when _{a 2 = 0.} R ^{23 to} R ³² are independently methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group or t-butyl group, respectively. From the viewpoint of crack resistance, it is preferably a methyl group or an ethyl group.

a ₁₆ , a ₁₇ and a _{20 to} a ₂₆ represent an integer from 0 to 4. From the viewpoint of crack resistance, it is preferably 0. a ₁₈ represents an integer of 1 to 10. From the viewpoint of crack resistance, it is preferably 1 to 4. a ₁₉ represents an integer from 0 to 3. From the viewpoint of crack resistance, it is preferably 0.

X _{1 to} X ₄ are independently single-bonded, -O-, -S-, -CH _2- , -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -CO- or-. It is a group represented by SO _2-.

The above is the structure when _{a 2 = 1.} R ^{33 to} R ⁴² are independently methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group or t-butyl group. From the viewpoint of crack resistance, it is preferably a methyl group or an ethyl group.

a ₂₇ , a ₂₈ , a ₃₁ , a ₃₃ and a ₃₅ each independently represent an integer of 0 to 3. From the viewpoint of crack resistance, it is preferably 0.

a ₃₂ , a ₃₄ , a ₃₆ and a ₃₇ each independently represent an integer of 0-4. From the viewpoint of crack resistance, it is preferably 0.

a ₂₉ represents an integer of 1 to 10. From the viewpoint of crack resistance, it is preferably 1 to 4. a ₃₀ represents an integer from 0 to 3. From the viewpoint of crack resistance, it is preferably 0.

X _{5 to} X ₈ are independently single-bonded, -O-, -S-, -CH _2- , -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -CO- or-. It is a group represented by SO _2-.
<When a _{2 = 2>}

The above is the structure when _{a 2 = 2.} R ^{43 to} R ⁵² are independently methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group or t-butyl group, respectively. From the viewpoint of crack resistance, it is preferably a methyl group or an ethyl group.

a ₃₈ and a ₃₉ each independently represent an integer of 0 to 2. From the viewpoint of crack resistance, it is preferably 0.

a _{40 to} a ₄₄ and a ₄₆ each independently represent an integer of 0 to 3. From the viewpoint of crack resistance, it is preferably 0.

a ₄₅ and a ₄₇ each independently represent an integer from 0 to 4. From the viewpoint of crack resistance, it is preferably 0.

X _{9 to} X ₁₂ are independently single-bonded, -O-, -S-, -CH _2- , -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -CO- or-, respectively. It is a group represented by SO _2-.

R ^{53 to} R ⁶² each independently represent a hydrogen atom, a halogen atom, or an organic group having 1 to 6 carbon atoms. Preferred specific examples of R ^{53 to} R ⁶² include hydrogen atom, chlorine atom, fluorine atom, saturated hydrocarbon group having 1 to 4 carbon atoms, cyclic saturated hydrocarbon group having 4 to 6 carbon atoms, trifluoromethyl group and the like. Can be mentioned. From the viewpoint of crack resistance, R ^{53 to} R ⁶² are more preferably methyl groups or ethyl groups.

a ₄₈ and a ₄₉ are independently integers from 0 to 4, and a ₄₈ + a ₄₉ <5. a ₅₁ is an integer from 0 to 6. a ₅₀ and a ₅₂ are each independently an integer of 0 to 2.

From the viewpoint of crack resistance, a ₄₈ + a ₄₉ <2 is preferable, a ₅₁ is preferably 0 to 2, more preferably 0, and a _{50 and a 52} are 0 to 1. It is preferable, and it is more preferable that it is 0.

From the viewpoint of crack resistance _{, it is more preferable that a 2} = 2 in _{the general formula (1) and R 2} is at least one selected from the following structures.

From the viewpoint of the initial efficiency of the battery when used as a separator for a non-aqueous electrolyte battery, ^{it is more preferable that R 2} is at least one selected from the following structures in the general formula (1).

The above is the structure when _{a 2 = 0.} a ₅₃ represents an integer of 1 to 10. From the viewpoint of crack resistance, it is preferably 1 to 4.

The above is the structure when _{a 2 = 1.}

The above is the structure when _{a 2 = 2.}

From the viewpoint of crack resistance improvement, in the general formula (1), in R ^1, the carbon atom to carbon atom and an amide group in which the -R ^{5-M +} is bound is bonded are adjacent (This is referred to as "bonding condition A") is preferable. Further, in R ² , ^{it is preferable that the carbon atom to which the −R 6-} M ⁺ is bonded and the carbon atom to which the amide group is bonded are adjacent to each other (this is referred to as “bonding condition B”). Then, it is particularly preferable that both the binding condition A and the binding condition B are satisfied. By satisfying at least one of the binding condition A and the binding condition B, the interaction between the molecules is weakened, and the rapid shrinkage during solvent evaporation is suppressed.

The unit structure represented by the general formula (1) is, for example, [1] a structure obtained by reacting a diamine composed of a secondary amine having a bifunctional group with a dicarboxylic acid having an acidic functional group or a derivative thereof, [1]. 2] A structure obtained by reacting a diamine composed of a secondary amine with a difunctional group and a tetracarboxylic acid or a derivative thereof, and [3] reacting a diamine composed of a secondary amine with a difunctional group with a tricarboxylic acid or a derivative thereof. [4] A structure obtained by reacting a diamine having an acidic functional group with a dicarboxylic acid or a derivative thereof, in which both the difunctional groups are composed of a secondary amine, and [5] a structure obtained by reacting the dicarboxylic acid or a derivative thereof. A structure obtained by reacting a diamine having an acidic functional group with a dicarboxylic acid having an acidic functional group or a derivative thereof, which is composed of a secondary amine and has an acidic functional group. A structure obtained by reacting a diamine having a group with a tetracarboxylic acid or a derivative thereof. [7] A diamine having an acidic functional group and having a secondary amine in both of the bifunctional groups is reacted with a tricarboxylic acid or a derivative thereof. It is preferable that the structure is obtained by subjecting the mixture, but the structure is not limited thereto.

From the viewpoint of improving crack resistance, the unit structure represented by the general formula (1) is preferably contained in an amount of 50 mol% or more, preferably 70 mol% or more, in the total repeating unit structure contained in the (a) polyamide resin. It is more preferably contained, and more preferably 90 mol% or more.

The content of the unit structure represented by the general formula (1) in the resin can be estimated by the following method. One is infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), thermal weight measurement-mass spectrometry (TG-MS), time-of-flight secondary ion mass spectrometry (TOF-SIMS), etc. It is a method of analysis with. Another method is to decompose the resin into each component and then analyze it by gas chromatography (GC), high performance liquid chromatography (HPLC), mass spectrometry (MS), FT-IR, NMR or the like. Yet another method is to incinerate the resin at a high temperature and then analyze it by elemental analysis or the like.

In particular, in the present invention, the resin is decomposed into each component and then analyzed by combining high performance liquid chromatography (HPLC) and mass spectrometry (MS).

(A) As the unit structure other than the unit structure represented by the general formula (1), which may be contained in the polyamide resin, the unit structures represented by the following general formulas (2) to (4) are preferable.

R ⁶³ , R ⁶⁷ and R ⁷⁰ each independently represent an organic group having 2 to 30 carbon atoms. From the viewpoint of solubility in water, it is preferably a hydrocarbon group, more preferably a hydrocarbon group having 2 to 15 carbon atoms, and further preferably a hydrocarbon group having 2 to 10 carbon atoms. Further, from the viewpoint of the initial efficiency of the battery when used as a separator for a non-aqueous electrolyte battery, it is preferable that ^{R 63} , R ⁶⁷ and R ^{70 are aliphatic groups.}

R ^65- , R ^69- and R ^72- each independently represent at least one anion selected from the group consisting of phenoxide anions, carboxylate anions and sulfonic acid anions. M ⁺ represents the counter cation to the anion.

a ₅₄ , a ₅₆ and a ₅₇ are independently integers from 0 to 4. Since a ₅₄ + a ₅₅ is> 0, when a ₅₅ is 0, a ₅₄ is an integer of 1 to 4. From the viewpoint of solubility in water, a ₅₄ , a ₅₆ and a ₅₇ are preferably integers of 0 to 4 independently of each other.

Specific examples of R ⁶³ , R ⁶⁷ and R ⁷⁰ include the same as those listed ^{in R 1.}

Furthermore, to improve adhesion to the _{^{substrate, -R 63 (-R 65- M +}} ) a 54 -, - R 67 (-R 69- M +) a 56 - and ^-R 70 ^{(-R 72-} 1 to 10 mol% of M ⁺ ) a ₅₇ − may be independently diamine residues containing a siloxane bond.

R ⁶⁴ , R ⁶⁸ and R ⁷¹ each independently represent an organic group having 3 to 30 carbon atoms. From the viewpoint of solubility in water, it is preferably a hydrocarbon group, more preferably a hydrocarbon group having 2 to 15 carbon atoms, and further preferably a hydrocarbon group having 2 to 10 carbon atoms. Further, from the viewpoint of the initial efficiency of the battery when used as a separator for a non-aqueous electrolyte battery, ^{it is preferable that R 64} , R ⁶⁸ and R ⁷¹ each independently have an aliphatic skeleton.

R ^66- represents at least one anion selected from the group consisting of phenoxide anions, carboxylate anions and sulfonic acid anions. M ⁺ represents the counter cation to the anion. a ₅₅ is an integer from 0 to 4. Since a ₅₄ + a ₅₅ is> 0, when a ₅₄ is 0, a ₅₅ is an integer of 1 to 4. From the viewpoint of crack _{resistance, a 55} is preferably an integer of 0 to 2.

Specific examples of R ⁶⁴ include the same as those listed in R ² _{when a 2 is 0 to 1.}

Specific examples of R ⁶⁸ include the same as those listed in R ² _{when a 2 is 2.}

Specific examples of R ⁷¹ include residues of trimellitic acid, trimesic acid, diphenyl ether tricarboxylic acid, and biphenyl tricarboxylic acid.

Further, the resin composition containing (a) a polyamide resin may be used by being mixed with a resin other than (a) a polyamide resin (hereinafter, referred to as “another resin”). Preferred specific examples of other resins include polyimide, (a) polyamides that do not correspond to polyamide resins, polyamideimides, polybenzoxazoles, acrylic resins, methacrylic resins, vinyl resins, phenol resins, cellulose resins and the like. Particularly preferred examples include polyvinyl alcohol, polyvinylpyrrolidone and carboxymethyl cellulose.

At this time, from the viewpoint of the strength and elastic modulus of the resin composition, the (a) polyamide resin is preferably contained in an amount of 80 mol% or more, more preferably 85 mol% or more, and further preferably 90 mol% or more. % Or more, most preferably 95 mol% or more.

(End sealant)
From the viewpoint of the stability of the aqueous solution and the dispersibility of the filler, the terminal skeleton of the resin containing the structure represented by the general formula (1) as a repeating unit is represented by the following general formulas (5), (6) and (7). It is preferable to include at least one selected from the structures to be used. These structures are introduced into the (a) polyamide resin by using an end-capping agent such as an acid anhydride, a monocarboxylic acid, and a monoamine compound when the (a) polyamide resin is polymerized.

R ⁷³ , R ⁷⁶ and R ⁷⁸ each independently represent an organic group having 3 to 30 carbon atoms. From the viewpoint of solubility in water, it is preferably a hydrocarbon group, more preferably a hydrocarbon group having 2 to 15 carbon atoms, and further preferably a hydrocarbon group having 2 to 10 carbon atoms. Further, from the viewpoint of initial efficiency when used as a negative electrode binder, it is preferably an aliphatic group.

R ^75- , R ^77- and R ^79- each independently represent at least one anion selected from the group consisting of phenoxide anions, carboxylate anions and sulfonic acid anions. M ⁺ represents the counter cation to the anion.

a _{58 to} a ₆₀ are independently integers of 0 to 3. From the viewpoint of solubility in water, a _{58 to} a ₆₀ are preferably integers of 1 to 3 independently of each other.

R ⁷⁴ represents a halogen atom or an organic group having 1 to 10 carbon atoms. Preferred specific examples of R ⁷⁴ include a fluoro group, a chloro group, a bromo group, an iodo group, a methyl group, an ethyl group, a propyl group, a butyl group, an isopropyl group, an isobutyl group, a t-butyl group, an isopentyl group and a hexyl group. Examples thereof include a trifluoromethyl group, a pentafluoroethyl group, a cyclobutyl group, a cyclohexyl group, a cyclopentyl group, a phenyl group and a naphthyl group. Further, R ⁷⁴ may be connected to a part of R ⁷³ to form an annular structure.

Specific examples of the amine giving the terminal structure represented by the general formula (5) include disodium 3,3'-iminodipropionate, sodium 3-piperidinecarboxylate, sodium azetidine-3-carboxylate, and 4-piperidinecarboxylic acid. Examples thereof include sodium acid and sodium 2-piperidine carboxylate.

Specific examples of the acid giving the terminal structure represented by the general formula (6) include sodium succinate, sodium maleate, sodium fumarate, sodium adipate, benzoic acid-4-sodium hydroxide, sodium nadicate, and cyclohexanedicarboxylic acid. Examples thereof include sodium acid and sodium phthalate-3-carboxylic acid.

Specific examples of the acid giving the terminal structure represented by the general formula (7) include sodium phthalic acid-3-carboxylate, phthalic acid-3-sodium hydroxide and the like.

The end sealant can be used alone or in combination of two or more. Moreover, you may use the terminal encapsulant other than these in combination.

(A) The content of the terminal encapsulant in the polyamide resin is preferably in the range of 0.1 to 60 mol% of the number of moles of the component monomers constituting the carboxylic acid residue and the amine residue, and is 5 to 5 50 mol% is more preferable. Within such a range, it is possible to obtain a resin composition having an appropriate viscosity of the solution at the time of coating and having excellent film physical characteristics.

A method for forming a structure containing an anion and a cation is preferably a method in which a basic compound is allowed to act on a phenolic hydroxyl group, a carboxylic acid and / or a sulfonic acid contained in a polyamide.

Examples of the basic compound include hydroxides and carbonates of alkali metals and alkaline earth metals, organic amines and the like. When these basic compounds are used, the counter cations in the present invention are alkali metal cations, alkaline earth metal cations, and ammonium cations, respectively.

In particular, a compound containing an alkali metal element is preferable from the viewpoint of further improving the strength and chemical resistance of the coating film prepared from the resin composition. ^{In this case, M +} in the general formula (1) is an alkali metal cation.

Crack resistance improvement, from the viewpoint of long term storage stability of the aqueous solution, in the general formula (1), a ^{2 =} 2 with R ² resin is a tetracarboxylic acid residue, and a base compound containing an alkali metal element Since it is a compound, ^{it is more preferable that R 6-} is a carboxylate anion and M ⁺ is an alkali metal cation. With such a tetracarboxylic acid residue, the carbon to which the amide group contained in the main chain is bonded and the R ^6- M ^{+ in the} side chain are adjacent to each other, and the crack resistance is improved. Further, by using a salt with an alkali metal, side reactions such as imidization and cross-linking may be further suppressed, which contributes to the improvement of long-term storage stability of the aqueous solution.

Examples of alkali metal hydroxides include lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide and cesium hydroxide. Two or more kinds of these may be contained. Lithium hydroxide, sodium hydroxide and potassium hydroxide are preferred from the viewpoint of improving the solubility and dispersion stability of the resin composition in water.

Examples of alkali metal carbonates include lithium carbonate, lithium hydrogen carbonate, sodium carbonate, sodium hydrogen carbonate, potassium carbonate, potassium hydrogen carbonate, rubidium hydrogen carbonate, cesium carbonate, cesium hydrogen carbonate and potassium sodium carbonate. can. Two or more kinds of these may be contained. From the viewpoint of solubility and dispersion stability of the resin composition in water, sodium carbonate, sodium hydrogen carbonate, potassium carbonate, potassium hydrogen carbonate and sodium potassium carbonate are preferable, sodium carbonate and sodium hydrogen carbonate are more preferable, and sodium carbonate is preferable. More preferred.

Examples of organic amines include aliphatic tertiary amines such as trimethylamine, triethylamine, triisopropylamine, tributylamine, triethanolamine and N-methylethanolamine, and aromatics such as pyridine, N, N-dimethylaminopyridine and rutidin. Examples thereof include quaternary ammonium salts such as amines, tetramethylammonium hydroxides and tetraethylammonium hydroxides. Two or more of these may be used.

Among the above, sodium carbonate is most preferable as the basic compound. That is, it is preferable that ^{M +} is Na ^+.

The amount of the basic compound to be blended is preferably 20 mol% or more in that the resin can be sufficiently dissolved with respect to 100 mol% of the total amount of the phenoxide anion, the carboxylate anion and the sulfonic acid anion in the (a) polyamide resin. , 50 mol% or more is more preferable. Further, 450 mol% or less is preferable, 400 mol% or less is more preferable, 300 mol% or less is preferable, and 250 mol% or less is most preferable, in that cracks can be prevented from being decomposed of the resin or formed into a coating film. ..

The solvent used in the polycondensation reaction is not particularly limited as long as the produced resin dissolves, but N-methyl-2-pyrrolidone, N-methylcaprolactam, N, N-dimethylacetamide, and the like. Aprotic polar solvents such as N, N-dimethylformamide, dimethyl sulfoxide, γ-butyrolactone and dimethylimidazoline, phenolic solvents such as phenol, m-cresol, chlorophenol and nitrophenol, polyphosphoric acid and phosphorus pentaoxide in phosphoric acid. A phosphorus-based solvent or the like to which the above is added can be preferably used.

Generally, a polyimide polymer is obtained by reacting an acid anhydride or a dicarboxylic acid diester with a diamine or a diisocyanate at a temperature of 150 ° C. or higher in these solvents. Further, in order to promote the reaction, bases such as triethylamine and pyridine can be added as a catalyst. Then, it is put into water or the like to precipitate a resin and dried to obtain a polymer as a solid, and then mixed with a basic compound to form a salt in a side chain.

In order to avoid contamination with impurities in the process, it is preferable to react in water in the presence of a basic compound. More preferably, a dicarboxylic acid or a derivative thereof, a tricarboxylic acid or a derivative thereof, a tetracarboxylic acid or a derivative thereof is added to water containing a basic compound or a diamine for polymerization.

((B) Water)
The resin composition containing (a) a polyamide resin preferably contains (b) water as a solvent. From the viewpoint of the stability of the aqueous solution, the water (b) in the solvent preferably occupies 80% by mass or more of the solvent contained in the resin composition. It is more preferably 90% by mass or more, and most preferably 99% by mass or more. Generally, in terms of suppressing gelation, (a) water is preferably 50 parts by mass or more, and more preferably 100 parts by mass or more with respect to 100 parts by mass of the polyamide resin. Further, in terms of suppressing decomposition, the amount of water (b) is preferably 100,000 parts by mass or less, and more preferably 3,000 parts by mass or less, based on 100 parts by mass of the resin of (a). ..

Further, the viscosity of the resin composition (a) containing the polyamide resin is preferably in the range of 1 mPa · s to 100 Pa · s at 25 ° C. from the viewpoint of workability.

(A) The resin composition containing the polyamide resin may contain a surfactant or the like from the viewpoint of further improving the coatability. Further, an organic solvent such as a lower alcohol such as ethanol or isopropyl alcohol or a polyhydric alcohol such as ethylene glycol or propylene glycol may be contained. The content of the organic solvent in the resin composition is preferably 50% by mass or less, more preferably 10% by mass or less of the entire resin composition.

(A) The method for preparing the resin composition containing the polyamide resin is not particularly limited, but it is safe to dissolve the resin powder little by little after dissolving a predetermined amount of the basic compound in water. Preferred from the point of view. When the neutralization reaction is slow, it may be heated in a water bath or an oil bath at about 30 to 110 ° C., or may be ultrasonically treated. After dissolution, water may be further added or concentrated to adjust the viscosity to a predetermined value.

As described above, in order to avoid contamination with impurities in the process, it is preferable to carry out the polymerization reaction of the resin in water in the presence of the basic compound. More preferably, a dicarboxylic acid or a derivative thereof, a tricarboxylic acid or a derivative thereof, a tetracarboxylic acid or a derivative thereof is added to water containing a basic compound or a diamine for polymerization.

The content of the (a) polyamide resin in the particle layer (II) is preferably 0.4 to 5.0 parts by mass with respect to 100 parts by mass of the inorganic filler. (A) By setting the content of the polyamide resin to 0.4 parts by mass or more, the inorganic filler can be firmly bound and the shape stability of the separator during heating can be further improved. The content of the polyamide resin (a) is more preferably 1.0 part by mass or more. On the other hand, by setting the content of the polyamide resin (a) to 5.0 parts by mass or less, clogging of the porous membrane (I) can be reduced and an increase in the air permeation resistance of the separator can be suppressed.

[3] Water-insoluble polymer The water-insoluble polymer has an effect of suppressing the desorption of the particle layer (II) from the porous film (I).

As the water-insoluble polymer, an electrochemically stable material that has electrical insulation, is stable against a non-aqueous electrolyte, and is not easily redox-reduced in the operating voltage range of the battery is preferable. Examples of such materials include styrene resin [polystyrene (PS), etc.], styrene-butadiene rubber (SBR), acrylic resin (PMMA, etc.), polyalkylene oxide [polyethylene oxide (PEO), etc.], and fluororesin (PVDF). Etc.), and derivatives thereof and the like. These resins may be crosslinked with urea resin, polyurethane or the like. Two or more of these may be used. Among these, styrene resin, acrylic resin and fluororesin are preferable, and acrylic resin is more preferable. Since the acrylic resin has a low glass transition temperature (Tg) and is highly flexible, it is possible to more effectively suppress the desorption of the particle layer (II) from the porous film (I). Resins with low Tg and high flexibility tend to have low shape stability during heating, but by containing the above-mentioned water-soluble polymer in the particle layer (II), softening at high temperatures is suppressed and softening during heating is suppressed. Desorption of the particle layer (II) from the porous film (I) can be further suppressed while improving the shape stability.

The content of the water-insoluble polymer in the particle layer (II) is preferably 0.5 to 5.0 parts by mass with respect to 100 parts by mass of the inorganic filler. By setting the content of the water-insoluble polymer to 0.5 parts by mass or more, the particle layer (II) is strongly bonded to the porous film (I) even during heating, so that the shape stability of the separator is further improved. Can be made to. The content of the water-insoluble polymer is more preferably 1.5 parts by mass or more with respect to 100 parts by mass of the inorganic filler. On the other hand, by setting the content of the water-insoluble polymer to 5.0 parts by mass or less, clogging of the porous membrane (I) can be reduced and an increase in the air permeation resistance of the separator can be suppressed.

If necessary, the particle layer (II) may contain various additives other than the above, such as antioxidants, preservatives, and surfactants.

The film thickness of the particle layer (II) is preferably 1 μm or more, more preferably 2 μm or more, and 3 More preferably, it is 5.5 μm or more. On the other hand, from the viewpoint of increasing the capacity of the non-aqueous electrolyte battery and reducing the air permeation resistance described later, the film thickness is preferably 10 μm or less, more preferably 5 μm or less, still more preferably 4.5 μm or less.

3. 3. Separator for non-aqueous electrolyte battery The air permeability resistance of the separator for non-aqueous electrolyte battery is preferably less than 150 s / 100 cc Air, more preferably less than 100 s / 100 cc Air, and even more preferably less than 45 s / 100 cc Air. When the air permeation resistance is 150 s / 100 ccAir or less, ion permeability can be ensured and deterioration of battery characteristics can be suppressed.

As described above, as for the air permeability resistance, how much the air permeability of the separator having the porous membrane (I) and the particle layer (II) increases with respect to the air permeability of only the porous membrane (I). It is a value indicating whether or not. The air permeability is measured according to JIS P-8117: 2009 using a Garley type densometer B type manufactured by Tester Sangyo Co., Ltd. The porous membrane (I) and the separator can be fixed between the clamping plate and the adapter plate so as not to have wrinkles, the air permeability can be measured, and the air permeability resistance can be calculated from the following formula. ..

Air permeability resistance (s / 100ccAir) = {Separator air permeability (s / 100ccAir)}-{Porous membrane (I) air permeability (s / 100ccAir)}
As a means for setting the air permeation resistance to 150 s / 100 ccAir or less, for example, by adjusting the contents of the water-soluble polymer and the water-insoluble polymer to the above-mentioned preferable ranges, the pores of the porous membrane (I) are formed. Examples include methods for reducing clogging.

The heat shrinkage of the separator for a non-aqueous electrolyte battery when heated at 160 ° C. for 1 hour is 10% or less, more preferably 5% or less, still more preferably less than 3%. The heat shrinkage rate is an index of shape stability during heating, and if the heat shrinkage rate when heated at 160 ° C. for 1 hour is 10% or less, even when the battery generates abnormal heat, the heat shrinkage of the separator causes the positive electrode. It is possible to prevent the negative electrodes from coming into contact with each other and causing a short circuit.

Here, the heat shrinkage rate refers to the ratio of the length of the separator after heating at a predetermined temperature to the length of the separator at room temperature. After cutting out a separator for a non-aqueous electrolyte battery to 45 mm × 45 mm, markings with a length of 35 mm are placed on the porous membrane (I) side of each of the mechanical direction (MD) side and the width direction (TD) side. .. The separator with the marking is placed in an oven heated to a predetermined temperature (150 ° C., 160 ° C., 180 ° C., 200 ° C.) while being sandwiched between papers, and heated for 1 hour. Then, the separator for a non-aqueous electrolyte battery is taken out from the oven, cooled to room temperature, the length of the MD and TD markings is measured, and the length of the shorter marking portion is d (mm). Calculate the shrinkage rate.
Heat shrinkage rate (%) = {(35-d) / 35} x 100.

Examples of means for reducing the heat shrinkage rate when heated at 160 ° C. for 1 hour include a method of adjusting the content of the water-soluble polymer to the above-mentioned preferable range.

More preferably, the separator for a non-aqueous electrolyte battery has a heat shrinkage rate when heated at 180 ° C. for 1 hour and a heat shrinkage rate when heated at 200 ° C. for 1 hour, both of which are 10% or less.

4. Method for Producing Separator for Non-Aqueous Electrolyte Battery The separator for non-aqueous electrolyte battery of the present invention has, for example, the above-mentioned inorganic filler, water-soluble polymer, water-insoluble polymer and solvent on at least one side of the porous film (I). It can be obtained by applying the slurry containing the above-mentioned material, removing the solvent, and forming the particle layer (II). The details will be described below.

[1] Method for producing slurry The method for producing a slurry of the present invention is a step of mixing at least an inorganic filler and water to obtain a dispersion, and the above-mentioned (a) polyamide prepared by using the dispersion and water as a solvent. The step of mixing with an aqueous solution of the resin is included.

The method for producing a slurry of the present invention includes at least a step of mixing an inorganic filler and water to obtain a dispersion. Examples of the method of mixing the inorganic filler and water to obtain a dispersion include a mechanical stirring method, an ultrasonic dispersion method, a high-pressure dispersion method, and a media dispersion method. Among these, a media dispersion method capable of dispersing the inorganic filler at a high level and in a short time is preferable.

Prior to the step of obtaining the dispersion, there may be a step of dissolving one or more polymers selected from the group consisting of cellulose ether, polyvinyl alcohol and sodium alginate in water. Further, from the viewpoint of dryness and coatability to the porous layer (I), a small amount of alcohol may be added to water.

The method for producing a slurry of the present invention includes a step of mixing the obtained dispersion with an aqueous solution of (a) a polyamide resin prepared using water as a solvent.

(A) The polyamide resin is reacted in water from the viewpoint of preventing impurities from being mixed in the process, simplifying the process, and reducing the raw material cost. Further, a method in which a dicarboxylic acid or a derivative thereof, a tricarboxylic acid or a derivative thereof, a tetracarboxylic acid or a derivative thereof is charged into water containing a basic compound or a diamine and polymerized is preferable.

[2] Method for producing porous membrane (I) Examples of the method for producing the porous membrane (I) include a foaming method, a phase separation method, a dissolution recrystallization method, a stretch opening method, and a powder sintering method. Be done. Among these, the phase separation method is preferable from the viewpoint of uniformity of fine pores and cost.

As a method for producing the porous film (I) by the phase separation method, for example, polyethylene and a molding solvent are heat-melted and kneaded, and the obtained melt mixture is extruded from a die and cooled to form a gel-like molded product. Then, a method of obtaining a porous film by stretching the obtained gel-like molded product in at least the uniaxial direction and removing the molding solvent can be mentioned.

[3] Method for Forming Particle Layer (II) The slurry obtained in [1] is applied to at least one surface of the porous film (I) obtained in [2], and the solvent is removed to remove the particle layer (2). It is preferable to form II).

Examples of the method for applying the slurry to the porous membrane (I) include a gravure coater method, a small diameter gravure coater method, a reverse roll coater method, a transfer roll coater method, a kiss coater method, a dip coater method, a knife coater method, and an air doctor coater. Examples include the method, blade coater method, rod coater method, squeeze coater method, cast coater method, die coater method, screen printing method, and spray coating method.

Examples of the method for removing the solvent include a method of fixing the porous membrane (I) and drying it by heating at a temperature below its melting point, a method of drying under reduced pressure, and the like. Among these, the method by heating and drying is preferable because it leads to simplification of the process.

The heat-drying temperature is preferably 70 ° C. or lower, more preferably 60 ° C. or lower, still more preferably 50 ° C. or lower, from the viewpoint of suppressing the expression of the pore closing function of the porous membrane (I) and reducing the amount of heat used. .. The heating and drying time is preferably several seconds to several minutes.

5. Non-aqueous electrolyte battery The separator for a non-aqueous electrolyte battery of the present invention can be suitably used for a battery using a non-aqueous electrolyte. Specifically, it is preferable as a separator for secondary batteries such as nickel-hydrogen batteries, nickel-cadmium batteries, nickel-zinc batteries, silver-zinc batteries, lithium secondary batteries, lithium ion secondary batteries, and lithium polymer secondary batteries. Can be used. Above all, it is preferable to use it as a separator for a lithium ion secondary battery.

In a non-aqueous electrolyte battery, a positive electrode and a negative electrode are laminated via a separator. The separator contains an electrolytic solution (electrolyte). The structure of the electrode is not particularly limited, and for example, an electrode structure (coin type) in which disk-shaped positive electrodes and negative electrodes are arranged so as to face each other, and an electrode structure in which flat plate-shaped positive electrodes and negative electrodes are alternately laminated (laminated type). ), An electrode structure in which a laminated strip-shaped positive electrode and a negative electrode are wound (wound type) and the like. The current collector, the positive electrode, the positive electrode active material, the negative electrode, the negative electrode active material, and the electrolytic solution used in the non-aqueous electrolyte battery are not particularly limited, and conventionally known materials can be appropriately combined and used.

Next, examples of the present invention will be described, but the present invention is not limited to these examples.

(Preparation of water-soluble polymer)
Synthesis Example 1: Synthesis of Resin A In a well-dried four-necked flask, 119.48 g of water and 8.815 g (100 mmol) of N, N'-dimethylethylenediamine (manufactured by Tokyo Chemical Industry Co., Ltd., hereinafter DMEDA) ), Sodium carbonate 10.60 g (100 mmol) was dissolved at room temperature with stirring under a nitrogen atmosphere. Then, 44.42 g (100 mmol) of 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride (manufactured by Tokyo Chemical Industry Co., Ltd., hereinafter, 6FDA) and 15.00 g of water were added. On the way, the polymerization reaction was carried out at 80 ° C. for 6 hours, paying attention to the generation of carbon dioxide. After completion of the reaction, the temperature was lowered to room temperature to obtain an aqueous solution A of a polyamide resin A having a sodium carboxylate in the side chain having a concentration of 30% by mass.

Synthesis Example 2: Synthesis of resin B Synthetic except that 119.01 g of water and 8.614 g (100 mmol) of piperazine (manufactured by Tokyo Chemical Industry Co., Ltd.) were used instead of 119.48 g of water and 8.815 g (100 mmol) of DMEDA. An aqueous solution B of a polyamide resin B having a sodium carboxylate in a side chain having a concentration of 30% by mass was obtained in the same manner as in Example 1.

Synthesis Example 3: Synthesis of resin C 87.75 g of water, bis (3,4-dicarboxyphenyl) ether dianhydride (manufactured by Tokyo Chemical Industry Co., Ltd.) instead of 119.01 g of water and 44.42 g (100 mmol) of 6FDA. Hereinafter, an aqueous solution C of a polyamide resin C having a sodium carboxylate in the side chain having a concentration of 30% by mass was obtained in the same manner as in Synthesis Example 2 except that 31.02 g (100 mmol) of ODPA) was used.

Synthesis Example 4: Synthesis of Resin D Instead of water 119.01 g and 6FDA 44.42 g (100 mmol), water 66.26 g and pyromellitic anhydride (manufactured by Tokyo Chemical Industry Co., Ltd., hereinafter PMDA) 21.81 g (100 mmol) ) Was used, and an aqueous solution D of a polyamide resin D having a sodium carboxylate in the side chain having a concentration of 30% by mass was obtained in the same manner as in Synthesis Example 2.

Synthesis Example 5: Synthesis of Resin E Instead of water 119.01 g, 6FDA 44.42 g (100 mmol), water 84.01 g, 3,3', 4,4'-biphenyltetracarboxylic acid dianhydride (Tokyo Chemical Industry (Tokyo Chemical Industry) An aqueous solution E of a polyamide resin E having a sodium carboxylate in a side chain having a concentration of 30% by mass was obtained in the same manner as in Synthesis Example 2 except that 29.42 g (100 mmol) of BPDA) manufactured by Tokyo Chemical Industry Co., Ltd. was used.

Synthesis Example 6: Synthesis of Resin F Instead of water 119.01 g, 6FDA 44.42 g (100 mmol), water 101.75 g, 3,3', 4,4'-terphenyltetracarboxylic acid dianhydride (Tokyo Kasei Kogyo) An aqueous solution F of a polyamide resin F having a sodium carboxylate in a side chain having a concentration of 30% by mass was obtained in the same manner as in Synthesis Example 2 except that 37.02 g (100 mmol) of TPDA (manufactured by TPDA) was used.

Synthesis Example 7: Synthesis of resin G Instead of 119.48 g of water, 8.815 g (100 mmol) of DMEDA, and 44.42 g (100 mmol) of 6FDA, 103.18 g of water, 4,4'-bipiperidine (manufactured by Tokyo Chemical Industry Co., Ltd.) An aqueous solution G of a polyamide resin G having a sodium carboxylate in a side chain having a concentration of 30% by mass was obtained in the same manner as in Synthesis Example 1 except that 16.83 g (100 mmol) and BPDA 29.42 g (100 mmol) were used.

Synthesis Example 8: Synthesis of Resin H 64.39 g of water, 1,2,3,4-cyclopentanetetracarboxylic acid dianhydride instead of 119.01 g of water and 44.42 g (100 mmol) of 6FDA (Tokyo Kasei Kogyo Co., Ltd.) ), Hereinafter, an aqueous solution H of a polyamide resin H having a sodium carboxylate in a side chain having a concentration of 30% by mass was obtained in the same manner as in Synthesis Example 2 except that 21.01 g (100 mmol) of CPDA) was used.

Synthesis Example 9: Synthesis of Resin I Instead of water 119.01 g, 6FDA 44.42 g (100 mmol), water 61.59 g, 1,2,3,4-butanetetracarboxylic acid dianhydride (manufactured by Wako Chemical Co., Ltd.) Hereinafter, an aqueous solution I of a polyamide resin I having a sodium carboxylate in the side chain having a concentration of 30% by mass was obtained in the same manner as in Synthesis Example 2 except that 19.81 g (100 mmol) of BTA) was used.

Synthesis Example 10: Synthesis of Resin J In a well-dried four-necked flask, 20.31 g (100 mmol) of 2-piperazin carboxylic acid dihydrochloride (manufactured by Tokyo Kasei Kogyo Co., Ltd., hereinafter 2PC) in 100 g of water. , Sodium carbonate 26.50 g (250 mmol) was dissolved at room temperature with stirring under a nitrogen atmosphere. 15.50 g (100 mmol) of succinic acid dichloride (manufactured by Tokyo Chemical Industry Co., Ltd.) dissolved in 30 g of methylene chloride was added dropwise thereto so that the temperature of the reaction vessel did not exceed 10 ° C. After completion of the dropping, the aqueous layer and the oil layer were separated, and 1N hydrochloric acid was dropped into the water tank. The precipitate obtained by dropping was separated into a furnace, washed repeatedly with pure water, and dried in a vacuum oven at 80 ° C. for 50 hours to obtain a powder of resin J.

2.65 g (25 mmol) of sodium carbonate was dissolved in 27.30 g of water at room temperature with stirring under a nitrogen atmosphere. 10.60 g of the above resin J powder was added thereto to obtain an aqueous solution J of the polyamide resin J having a sodium carboxylate in the side chain having a concentration of 30% by mass.

Synthesis Example 11: Synthesis of Resin K In a well-dried four-necked flask, 20.31 g (100 mmol) of 2-piperazinecarboxylic acid dihydrochloride (manufactured by Tokyo Kasei Kogyo Co., Ltd., hereinafter 2PC) in 100 g of water. , Sodium carbonate 26.50 g (250 mmol) was dissolved at room temperature with stirring under a nitrogen atmosphere. 18.30 g (100 mmol) of adipoyl dichloride (manufactured by Tokyo Chemical Industry Co., Ltd.) dissolved in 30 g of methylene chloride was added dropwise thereto so that the temperature of the reaction vessel did not exceed 10 ° C. After completion of the dropping, the aqueous layer and the oil layer were separated, and 1N hydrochloric acid was dropped into the water tank. The precipitate obtained by dropping was separated into a furnace, washed repeatedly with pure water, and dried in a vacuum oven at 80 ° C. for 50 hours to obtain a powder of resin K.

2.65 g (25 mmol) of sodium carbonate was dissolved in 30.58 g of water at room temperature with stirring under a nitrogen atmosphere. To this, 12.00 g of the above resin K powder was added to obtain an aqueous solution K of the polyamide resin K having a sodium carboxylate in the side chain having a concentration of 30% by mass.

Synthesis Example 12: Synthesis of resin L In a well-dried four-necked flask, 3,3'-dicarboxy-4,4'-diaminodiphenylmethane (manufactured by Wakayama Seika Kogyo Co., Ltd., product) was added to 131.79 g of NMP. Name "MBAA") 27.20 g (95 mmol) and para-phenylenediamine (manufactured by Tokyo Chemical Industry Co., Ltd., hereinafter, PDA) 0.54 g (5 mmol) were dissolved at room temperature with stirring under a nitrogen atmosphere. Then, 19.81 g (100 mmol) of BTA and 15.00 g of NMP were added, and the mixture was reacted at 40 ° C. for 2 hours. Then, the polymerization reaction was carried out at 200 ° C. for 6 hours while distilling off the water generated during the reaction. After completion of the reaction, the temperature was lowered to room temperature, the solution was poured into 3 L of water, the obtained precipitate was filtered off, and washed 3 times with 1.5 L of water. The washed solid was dried in a ventilation oven at 50 ° C. for 3 days to obtain a resin L solid.

5.3 g (50 mmol) of sodium carbonate was dissolved in 56.37 g of water at room temperature with stirring under a nitrogen atmosphere. 21.98 g of the above resin L powder was added thereto to obtain an aqueous solution L of the polyimide resin L having a sodium carboxylate in the side chain having a concentration of 30% by mass.

Synthesis Example 13: Synthesis of Resin M In a well-dried four-necked flask, 28.63 g (100 mmol) of MBAA was dissolved in 131.79 g of NMP with stirring under a nitrogen atmosphere. Then, the flask was ice-cooled, and 20.30 g (100 mmol) of isophthaloyl chloride (manufactured by Tokyo Chemical Industry Co., Ltd., hereinafter, IPC) dissolved in 15.00 g of NMP was added dropwise while keeping the temperature of the solution at 30 ° C. or lower. bottom. After charging the whole amount, it was reacted at 30 ° C. for 4 hours. This solution was poured into 3 L of water, the obtained precipitate was filtered off, and washed 3 times with 1.5 L of water. The washed solid was dried in a ventilation oven at 50 ° C. for 3 days to obtain a resin M solid.

5.3 g (50 mmol) of sodium carbonate was dissolved in 53.69 g of water at room temperature with stirring under a nitrogen atmosphere. To this, 20.82 g of the above resin M powder was added to obtain an aqueous solution M of the polyamide resin M having a sodium carboxylate in the side chain having a concentration of 30% by mass.

Synthesis Example 14: Synthesis of Resin N In a well-dried four-necked flask, 280.0 g of NMP and 14.44 g (95 mmol) of 3,5-diaminobenzoic acid (manufactured by Tokyo Kasei Co., Ltd., hereinafter DAB), 1.240 g (5 mmol) of 1,3-bis-3-aminopropyltetramethyldisiloxane (manufactured by Toray Dow Corning Silicone Co., Ltd., hereinafter APDS) was dissolved in a nitrogen atmosphere with stirring. Then, 31.02 g (100 mmol) of ODPA and 15.00 g of NMP were added and reacted at 50 to 60 ° C. for 1 hour, then 0.1 g of isoquinoline and 30 mL of toluene were added, the temperature of the solution was raised to 180 ° C., and distillation was performed. The reaction was carried out while removing the water to be added. After completion of the reaction, the solution temperature was lowered to room temperature, and then this solution was poured into 5 L of water to obtain a yellowish white solid. This was collected by filtration, further washed with 1 L of water, filtered, and dried in a ventilation oven at 50 ° C. for 72 hours to obtain a solid resin N.

5.3 g (50 mmol) of sodium carbonate was dissolved in 55.42 g of water at room temperature with stirring under a nitrogen atmosphere. To this, 21.55 g of the above resin N powder was added to obtain an aqueous solution N of the polyimide resin N having a sodium carboxylate in the side chain having a concentration of 30% by mass.

(Preparation of aqueous resin solution)
Resin aqueous solution 1
100.00 g of water was added to 10.00 g of carboxymethyl cellulose and stirred at 23 ° C. to obtain a resin aqueous solution 1.

(Evaluation method)
1. 1. Observation of coating film surface The appearance of the separator for a non-aqueous electrolyte battery obtained in each Example and Comparative Example was visually observed, and it was evaluated as good when there was no unevenness or streaks, and as defective when there was unevenness or streaks.

2. Air Permeation Resistance Evaluation Using a Garley type densometer B type manufactured by Tester Sangyo Co., Ltd., the porous membrane (I) used in each Example and Comparative Example and the obtained separator were clan, respectively. It was fixed between the ping plate and the adapter plate so as not to have wrinkles, the air permeability was measured according to JIS P-8117: 2009, and the air permeability resistance was calculated from the following formula.

Air permeability resistance (s / 100ccAir) = {Separator air permeability (s / 100ccAir)}-{Porous membrane (I) air permeability (s / 100ccAir)}
Less than 45s / 100ccAir was evaluated as A, 45s / 100ccAir or more and less than 100s / 100ccAir was evaluated as B, 100s / 100ccAir or more and less than 150s / 100ccAir was evaluated as C, and 150s / 100ccAir or more was evaluated as D.

3. 3. Evaluation of shape stability during heating After cutting out the separator for non-aqueous electrolyte battery obtained in each Example and Comparative Example to 45 mm × 45 mm, the sides in the mechanical direction (MD) and the sides in the width direction (TD) are porous. Markings with a length of 35 mm were placed on the quality film (I) side. The marking separator was placed in an oven heated to temperatures of 150 ° C., 180 ° C. and 200 ° C., respectively, while being sandwiched between papers, and heated for 1 hour. Then, the separator for a non-aqueous electrolyte battery is taken out from the oven, cooled to room temperature, the length of the MD and TD markings is measured, and the length of the shorter marking portion is d (mm). The shrinkage rate was calculated.

Heat shrinkage rate (%) = {(35-d) / 35} x 100
The heat shrinkage was measured at each temperature of 150 ° C., 180 ° C. and 200 ° C., and less than 5% was evaluated as A, 5% or more and 10% or less was evaluated as B, and a value greater than 10% was evaluated as C.

Example 1
Alumina having an average particle size of 0.5 μm and an aqueous resin solution 1 were mixed with 100 parts by mass of alumina so that the resin solid content was 0.5 parts by mass to obtain a ceramic slurry. Further, the concentration was adjusted with water so that the content of alumina in the ceramic slurry was 50% by mass. This ceramic slurry was mixed using a high-speed shearing stirrer (DESPA, manufactured by Asada Iron Works Co., Ltd.), and further dispersed using a continuous media disperser (NANO GRAIN MILL, manufactured by Asada Iron Works Co., Ltd.).

Aqueous solution A was added to this dispersion so that resin A was 1.5 parts by mass with respect to 100 parts by mass of alumina and mixed using a three-one motor with propeller blades to obtain a ceramic slurry containing resin A.

Next, a monomer mixture was prepared by mixing 78 parts by mass of 2-ethylhexyl acrylate, 19.8 parts by mass of acrylonitrile, and 2 parts by mass of methacrylic acid and 0.2 parts by mass of allyl methacrylate (AMA). In a separate container, 70 parts by mass of ion-exchanged water, 0.2 parts by mass of sodium dodecylbenzene sulfonate, 0.3 parts by mass of ammonium perfluate, and sodium polyoxyethylene alkyl ether sulfate as an emulsifier (manufactured by Kao Chemical Co., Ltd., "Emar" (Registered Trademark) D-3-D ") 0.82 parts by mass and polyoxyethylene lauryl ether (manufactured by Kao Chemical Co., Ltd.," Emargen (registered trademark) -120 ") 0.59 parts by mass are mixed and combined. The phase part was replaced with nitrogen gas, and the temperature was raised to 60 ° C. The above-mentioned monomer mixture was added to the container and emulsion polymerization was carried out to prepare an aqueous dispersion of an acrylic resin.

The aqueous dispersion of the acrylic resin was added to the ceramic slurry containing the resin A so that the amount of the acrylic resin was 2.0 parts by mass with respect to 100 parts by mass of alumina, and the particles were mixed using a three-one motor with propeller blades. A slurry for forming the layer (II) was obtained.

Next, as the porous membrane (I), a polyethylene porous membrane (thickness 12 μm, air permeability 160 s / 100 ccAir, heat shrinkage rate of 150 ° C. 80%) was prepared. The particle layer (II) forming slurry is applied to one side of the porous film (I) using a gravure coating machine, and dried at 50 ° C. for 1 minute to form a particle layer on the porous film (I). (II) was formed to obtain a separator for a non-aqueous electrolyte battery. The film thickness of the particle layer (II) in the obtained separator for a non-aqueous electrolyte battery was 4.0 μm.

Examples 2-11
A slurry was obtained in the same manner as in Example 1 except that the aqueous resin solution was changed as shown in Table 1. Using the obtained slurry, a particle layer (II) was formed on the porous film (I) in the same manner as in Example 1 to obtain a separator for a non-aqueous electrolyte battery. The film thickness of the particle layer (II) of the obtained separator for a non-aqueous electrolyte battery was 4.0 μm.

Example 12
Barium sulfate having an average particle size of 0.5 μm and the resin aqueous solution 1 were mixed with 100 parts by mass of barium sulfate so that the resin solid content was 0.43 parts by mass to obtain a barium sulfate slurry. Further, the concentration was adjusted with water so that the content of barium sulfate in the barium sulfate slurry was 50% by mass. This barium sulfate slurry was mixed using a high-speed shearing stirrer (DESPA, manufactured by Asada Iron Works Co., Ltd.), and further dispersed using a continuous media disperser (NANO GRAIN MILL, manufactured by Asada Iron Works Co., Ltd.). ..

Aqueous solution E was added to the dispersion liquid so that the amount of resin E was 1.3 parts by mass with respect to 100 parts by mass of barium sulfate, and the mixture was mixed using a three-one motor with propeller blades to obtain a barium sulfate slurry containing resin E.

Next, an aqueous dispersion of acrylic resin was prepared in the same manner as in Example 1.

The aqueous dispersion of the acrylic resin was added to the barium sulfate slurry containing the resin E so that the amount of the acrylic resin was 1.7 parts by mass with respect to 100 parts by mass of the barium sulfate, and the mixture was mixed using a three-one motor with propeller blades. , A slurry for forming the particle layer (II) was obtained.

Next, using the obtained slurry, a particle layer (II) was formed on the porous film (I) in the same manner as in Example 1 to obtain a separator for a non-aqueous electrolyte battery. The film thickness of the particle layer (II) of the obtained separator for a non-aqueous electrolyte battery was 4.0 μm.

Example 13
The slurry for forming the particle layer (II) was prepared in the same manner as in Example 1 except that the ceramic slurry and the resin aqueous solution E were mixed so that the resin E was 0.5 parts by mass with respect to 100 parts by mass of alumina. Obtained. Using the obtained slurry, a particle layer (II) was formed on the porous film (I) in the same manner as in Example 1 to obtain a separator for a non-aqueous electrolyte battery. The film thickness of the particle layer (II) of the obtained separator for a non-aqueous electrolyte battery was 4.0 μm.

Example 14
The slurry for forming the particle layer (II) was prepared in the same manner as in Example 1 except that the ceramic slurry and the resin aqueous solution E were mixed so that the resin E was 3.0 parts by mass with respect to 100 parts by mass of alumina. Obtained. Using the obtained slurry, a particle layer (II) was formed on the porous film (I) in the same manner as in Example 1 to obtain a separator for a non-aqueous electrolyte battery. The film thickness of the particle layer (II) of the obtained separator for a non-aqueous electrolyte battery was 4.0 μm.

Example 15
The slurry for forming the particle layer (II) was prepared in the same manner as in Example 1 except that the ceramic slurry and the resin aqueous solution E were mixed so that the resin E was 4.5 parts by mass with respect to 100 parts by mass of alumina. Obtained. Using the obtained slurry, a particle layer (II) was formed on the porous film (I) in the same manner as in Example 1 to obtain a separator for a non-aqueous electrolyte battery. The film thickness of the particle layer (II) of the obtained separator for a non-aqueous electrolyte battery was 4.0 μm.

Example 16
The slurry for forming the particle layer (II) was prepared in the same manner as in Example 1 except that the ceramic slurry and the resin aqueous solution E were mixed so that the resin E was 6.0 parts by mass with respect to 100 parts by mass of alumina. Obtained. Using the obtained slurry, a particle layer (II) was formed on the porous film (I) in the same manner as in Example 1 to obtain a separator for a non-aqueous electrolyte battery. The film thickness of the particle layer (II) of the obtained separator for a non-aqueous electrolyte battery was 4.0 μm.

Example 17
A slurry for forming the particle layer (II) was obtained in the same manner as in Example 1 except that the amount of the acrylic resin added was 0.8 parts by mass with respect to 100 parts by mass of alumina. Using the obtained slurry, a particle layer (II) was formed on the porous film (I) in the same manner as in Example 1 to obtain a separator for a non-aqueous electrolyte battery. The film thickness of the particle layer (II) of the obtained separator for a non-aqueous electrolyte battery was 4.0 μm.

Example 18
A slurry for forming the particle layer (II) was obtained in the same manner as in Example 1 except that the amount of the acrylic resin added was 3.0 parts by mass with respect to 100 parts by mass of alumina. Using the obtained slurry, a particle layer (II) was formed on the porous film (I) in the same manner as in Example 1 to obtain a separator for a non-aqueous electrolyte battery. The film thickness of the particle layer (II) of the obtained separator for a non-aqueous electrolyte battery was 4.0 μm.

Example 19
A slurry for forming the particle layer (II) was obtained in the same manner as in Example 1 except that the amount of the acrylic resin added was 4.5 parts by mass with respect to 100 parts by mass of alumina. Using the obtained slurry, a particle layer (II) was formed on the porous film (I) in the same manner as in Example 1 to obtain a separator for a non-aqueous electrolyte battery. The film thickness of the particle layer (II) of the obtained separator for a non-aqueous electrolyte battery was 4.0 μm.

Example 20
A slurry for forming the particle layer (II) was obtained in the same manner as in Example 1 except that the amount of the acrylic resin added was 6.0 parts by mass with respect to 100 parts by mass of alumina. Using the obtained slurry, a particle layer (II) was formed on the porous film (I) in the same manner as in Example 1 to obtain a separator for a non-aqueous electrolyte battery. The film thickness of the particle layer (II) of the obtained separator for a non-aqueous electrolyte battery was 4.0 μm.

Comparative Examples 1 to 3
A slurry was obtained in the same manner as in Example 1 except that the aqueous resin solution was changed as shown in Table 1. Using the obtained slurry, a particle layer (II) was formed on the porous film (I) in the same manner as in Example 1 to obtain a separator for a non-aqueous electrolyte battery. The film thickness of the particle layer (II) of the obtained separator for a non-aqueous electrolyte battery was 4.0 μm.

Comparative Example 4
A slurry was obtained in the same manner as in Example 1 except that the aqueous solution A was not added. Using the obtained slurry, a particle layer (II) was formed on the porous film (I) in the same manner as in Example 1 to obtain a separator for a non-aqueous electrolyte battery. The film thickness of the particle layer (II) of the obtained separator for a non-aqueous electrolyte battery was 4.0 μm.

Comparative Example 5
Weigh the resin aqueous solution 1, aqueous solution E, and acrylic resin so that the ratio of each solid content to the mass is 1: 3: 4, add water so that the total concentration of the aqueous solution is 10% by mass, and propeller. Mixing was performed using a three-one motor with blades to obtain a slurry for forming a particle layer (II).

Next, using the obtained slurry, a particle layer (II) was formed on the porous film (I) in the same manner as in Example 1 to obtain a separator for a non-aqueous electrolyte battery. The film thickness of the particle layer (II) of the obtained separator for a non-aqueous electrolyte battery was 0.5 μm.

The compositions of Examples 1 to 20 and Comparative Examples 1 to 5 are shown in Table 1, and the evaluation results are shown in Table 2.

The separators for non-aqueous electrolyte batteries of Examples 1 to 20 had small heat shrinkage rates at 150 ° C. and 180 ° C., and were excellent in shape stability at 160 ° C. On the other hand, the separators for non-aqueous electrolyte batteries of Comparative Examples 1 to 5 had a large heat shrinkage rate at 150 ° C. or higher and did not have shape stability. From Table 2, Examples 1 to 20 have a heat shrinkage rate of 10% or less when heated at 160 ° C. for 1 hour, and Comparative Examples 1 to 5 have a heat shrinkage rate when heated at 160 ° C. for 1 hour. It is clear that it is 10% or more.

Claims (29)

The inorganic filler contains an inorganic filler, a solvent and a water-soluble polymer, and the inorganic filler is alumina, barium sulfate, boehmite, calcium carbonate, calcium phosphate, calcium sulfate, calcium oxide, magnesium hydroxide, magnesium carbonate, magnesium oxide, magnesium sulfate, kaolin, One or more selected from the group consisting of talc, titanium dioxide, calcium fluoride, lithium fluoride, zeolite, molybdenum sulfide and mica, and the water-soluble polymer is (a) a polyamide resin and (a) a polyamide resin. However, at least one selected from the group consisting of a phenoxide anion, a carboxylate anion and a sulfonate anion, having a structure in which a hydrogen atom bonded to a nitrogen atom of an amide group is substituted with another group in the main chain. A slurry which is a resin containing an anion and a countercation for the anion in a side chain. (A) The slurry according to claim 1, wherein the polyamide resin contains a structure represented by the following general formula (1) as a repeating unit.

(R ¹ represents an organic group having 2 to 30 carbon atoms. R ² represents an organic group having 3 to 30 carbon atoms. R ³ and R ⁴ are independently halogen atoms or organic groups having 1 to 10 carbon atoms, respectively. A group is shown. At least one of R ³ and R ^{4 may be connected to a part of R 1} to form an annular structure, and R ³ and R ⁴ may be directly bonded to form an annular structure. R ^5- and R ^6- may each independently represent at least one anion selected from the group consisting of a phenoxide anion, a carboxylate anion and a sulfonic acid anion. M ⁺ represents a counter cation to the anion. Represented. A ₁ and a ₂ are integers from 0 to 4, and a ₁ + a ₂ > 0.) The slurry according to claim 2, wherein in the general formula (1), -N (R ³ ) -R ¹ (R ⁵ ) a _1- N (R ^{4)-is at least one selected from the following structures.}

(R ^{7 to} R ¹⁰ are each independently a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group or a t-butyl group. R ^11- and R ^13- , R ^15- , R ^17- , R ^19- and R ^21- , respectively, independently represent at least one of a carboxylate anion and a sulfonate anion. M ⁺ represents a counter cation to the anion. R ^12,, R ¹⁴ , R ¹⁶ , R ¹⁸ , R ²⁰ and R ²² each independently represent a hydrocarbon group having 1 to 4 carbon atoms. A ₃ represents an integer of 1 to _{6. a 4} , a 6, a. ₈ , a ₁₀ , a ₁₂ and a ₁₄ each independently represent an integer of _{0 to 4, and when a 2} = 0, they represent an integer of 1 to 4. a ₅ , a ₇ , a ₉ , a ₁₁ , A ₁₃ and a ₁₅ each independently represent an integer of 0 to _4. a 4 + a ₅ , a ₆ + a ₇ , a ₁₂ + a ₁₃ and a ₁₄ + a ₁₅ are independent integers of 0 to 4, respectively. A ₈ + a ₉ represents an integer from 0 to 5. a ₁₀ + a ₁₁ represents an integer from 0 to 6.) In the general formula ^{(1), -R 2 (R} 6) a 2 - R 2 parts of at least one selected from the following structures, a slurry of claim 2 or 3.

(The above is the structure when _{a 2} ^{= 0. R 23 to} R ³² are independently methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group or It is a t-butyl group. A ₁₆ , a ₁₇ and a _{20 to} a ₂₆ represent an integer of 0 to 4. a ₁₈ represents an integer of 1 to 10. A ₁₉ represents an integer of 0 to 3. X. _{1 to} X ₄ are independently single-bonded, -O-, -S-, -CH _2- , -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -CO- or -SO. It is a group indicated by _2-)

(The above is the structure when _{a 2} ^{= 1. R 33 to} R ⁴² are independently methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group or The t-butyl groups a ₂₇ , a ₂₈ , a ₃₁ , a ₃₃ and a ₃₅ each independently represent an integer of 0 to 3. a ₃₂ , a ₃₄ , a ₃₆ and a ₃₇ are independent, respectively. _{, A 29} represents an integer of 1 to 10. a ₃₀ represents an integer of 0 to 3. X _{5 to} X ₈ represent butyl, -O-, respectively. -S-, -CH _2- , -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -CO- or -SO _2- )

(The above is the structure when _{a 2} ^{= 2. R 43 to} R ⁵² are independently methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group or The t-butyl groups a ₃₈ and a ₃₉ each independently represent an integer of 0 to 2. a _{40 to} a ₄₄ and a ₄₆ each independently represent an integer of 0 to 3. a _45. And a ₄₇ each independently represent an integer of 0 to 4. X _{9 to} X ₁₂ are independently single-coupled, -O-, -S-, -CH _2- , -C (CH ₃ ). _2- , -C (CF ₃ ) _2- , -CO- or -SO _2-. R ^{53 to} R ⁶² are independently hydrogen atoms, halogen atoms or 1 to 6 carbon atoms. Indicates an organic group. A ₄₈ and a ₄₉ are independently integers from 0 to 4, and a ₄₈ + a ₄₉ <5. A ₅₁ is an integer from 0 to 6. a ₅₀ and a _52. Are independently integers from 0 to 2.) Any one of claims 2 to 4 in the general formula (1), wherein a ₂ = 2 and the R ^{2 portion of −R 2} (R ⁶ ) a ₂ − is at least one selected from the following structures. The slurry described in.

The slurry according to any one of claims 2 to 5, wherein in the general formula (1), the R ^{2 portion of −R 2} (R ⁶ ) a _{2 − is at least one selected from the following structures.}

(The above is the structure when _{a 2 = 0. A 53} represents an integer of 1 to 10.)

(The above is the structure when _{a 2 = 1.)}

(The above is the structure when _{a 2 = 2.)} The slurry according to any one of claims 2 to 6, which satisfies at least one of the following binding conditions A and B;
^{Bonding condition A: In R 1} in the general formula (1), the ^{carbon atom to which the −R 5-} M ⁺ is bonded and the carbon atom to which the amide group is bonded are adjacent to each other;
Coupling conditions B: In the general formula (1), in R ^2, the carbon atom to which the -R ^6- M carbon atoms and an amide ^{group +} is bonded is bonded are adjacent. The slurry according to any one of claims 2 to 7, wherein the M ^{+ is an alkali metal cation.} The slurry according to any one of claims 1 to 8, wherein the inorganic filler contains alumina or barium sulfate. The slurry according to any one of claims 1 to 9, which contains 0.4 to 5.0 parts by mass of (a) a polyamide resin with respect to 100 parts by mass of the inorganic filler. The slurry according to any one of claims 1 to 10, which contains 0.5 to 5.0 parts by mass of a water-insoluble polymer with respect to 100 parts by mass of the inorganic filler. The slurry according to any one of claims 1 to 11, wherein the solvent is water. The slurry according to any one of claims 1 to 12, further comprising one or more polymers selected from the group consisting of cellulose ether, polyvinyl alcohol and sodium alginate. The slurry according to claim 13, wherein the cellulose ether is carboxymethyl cellulose. 13. Slurry manufacturing method. It has a porous membrane (I) containing a polyolefin resin and a particle layer (II) containing an inorganic filler, a water-soluble polymer and a water-insoluble polymer.
The water-soluble polymer is (a) a polyamide resin, and (a) the polyamide resin has a structure in which a hydrogen atom bonded to a nitrogen atom of an amide group is substituted with another group in the main chain, and phenoxide. A separator for a non-aqueous electrolyte battery, which is a resin containing at least one anion selected from the group consisting of an anion, a carboxylate anion, and a sulfonic acid anion and a counter cation with respect to the anion in a side chain, and is 1 at 160 ° C. A separator for a non-aqueous electrolyte battery having a heat shrinkage rate of 10% or less when heated for an hour. The separator for a non-aqueous electrolyte battery according to claim 16, wherein the heat shrinkage rate when heated at 180 ° C. for 1 hour and the heat shrinkage rate when heated at 200 ° C. for 1 hour are both 10% or less. (A) The separator for a non-aqueous electrolyte battery according to claim 16 or 17, wherein the polyamide resin contains a structure represented by the following general formula (1) as a repeating unit.

(R ¹ represents an organic group having 2 to 30 carbon atoms. R ² represents an organic group having 3 to 30 carbon atoms. R ³ and R ⁴ are independently halogen atoms or organic groups having 1 to 10 carbon atoms, respectively. A group is shown. At least one of R ³ and R ^{4 may be connected to a part of R 1} to form an annular structure, and R ³ and R ⁴ may be directly bonded to form an annular structure. R ^5- and R ^6- may each independently represent at least one anion selected from the group consisting of a phenoxide anion, a carboxylate anion and a sulfonic acid anion. M ⁺ represents a counter cation to the anion. Represented. A ₁ and a ₂ are integers from 0 to 4, and a ₁ + a ₂ > 0.) The non-aqueous electrolyte according to claim 18, wherein in the general formula (1), -N (R ³ ) -R ¹ (R ⁵ ) a _1- N (R ^{4)-is at least one selected from the following structures.} Battery separator.

(R ^{7 to} R ¹⁰ are each independently a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group or a t-butyl group. R ^11- and R ^13- , R ^15- , R ^17- , R ^19- and R ^21- , respectively, independently represent at least one of a carboxylate anion and a sulfonate anion. M ⁺ represents a counter cation to the anion. R ^12,, R ¹⁴ , R ¹⁶ , R ¹⁸ , R ²⁰ and R ²² each independently represent a hydrocarbon group having 1 to 4 carbon atoms. A ₃ represents an integer of 1 to _{6. a 4} , a 6, a. ₈ , a ₁₀ , a ₁₂ and a ₁₄ each independently represent an integer of _{0 to 4, and when a 2} = 0, they represent an integer of 1 to 4. a ₅ , a ₇ , a ₉ , a ₁₁ , A ₁₃ and a ₁₅ each independently represent an integer of 0 to _4. a 4 + a ₅ , a ₆ + a ₇ , a ₁₂ + a ₁₃ and a ₁₄ + a ₁₅ are independent integers of 0 to 4, respectively. A ₈ + a ₉ represents an integer from 0 to 5. a ₁₀ + a ₁₁ represents an integer from 0 to 6.) The separator for a non-aqueous electrolyte battery according to claim 18 or 19, wherein in the general formula (1), the R ^{2 portion of −R 2} (R ⁶ ) a _{2 − is at least one selected from the following structures.}

(The above is the structure when _{a 2} ^{= 0. R 23 to} R ³² are independently methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group or It is a t-butyl group. A ₁₆ , a ₁₇ and a _{20 to} a ₂₆ represent an integer of 0 to 4. a ₁₈ represents an integer of 1 to 10. A ₁₉ represents an integer of 0 to 3. X. _{1 to} X ₄ are independently single-bonded, -O-, -S-, -CH _2- , -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -CO- or -SO. It is a group indicated by _2-)

(The above is the structure when _{a 2} ^{= 1. R 33 to} R ⁴² are independently methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group or The t-butyl groups a ₂₇ , a ₂₈ , a ₃₁ , a ₃₃ and a ₃₅ each independently represent an integer of 0 to 3. a ₃₂ , a ₃₄ , a ₃₆ and a ₃₇ are independent, respectively. _{, A 29} represents an integer of 1 to 10. a ₃₀ represents an integer of 0 to 3. X _{5 to} X ₈ represent butyl, -O-, respectively. -S-, -CH _2- , -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -CO- or -SO _2- )

(The above is the structure when _{a 2} ^{= 2. R 43 to} R ⁵² are independently methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group or The t-butyl groups a ₃₈ and a ₃₉ each independently represent an integer of 0 to 2. a _{40 to} a ₄₄ and a ₄₆ each independently represent an integer of 0 to 3. a _45. And a ₄₇ each independently represent an integer of 0 to 4. X _{9 to} X ₁₂ are independently single-coupled, -O-, -S-, -CH _2- , -C (CH ₃ ). _2- , -C (CF ₃ ) _2- , -CO- or -SO _2-. R ^{53 to} R ⁶² are independently hydrogen atoms, halogen atoms or 1 to 6 carbon atoms. Indicates an organic group. A ₄₈ and a ₄₉ are independently integers from 0 to 4, and a ₄₈ + a ₄₉ <5. A ₅₁ is an integer from 0 to 6. a ₅₀ and a _52. Are independently integers from 0 to 2.) Any of claims 18 to 20, wherein in the general formula (1), a ₂ = 2 and the R ^{2 portion of −R 2} (R ⁶ ) a _{2 − is at least one selected from the following structures.} Separator for non-aqueous electrolyte battery described in.

The separator for a non-aqueous electrolyte battery according to any one of claims 18 to 21, wherein ^{the R 2 portion of −R 2} (R ⁶ ) a ₂ − in the general formula (1) is at least one selected from the following structures. ..

(The above is the structure when _{a 2 = 0. A 53} represents an integer of 1 to 10.)

(The above is the structure when _{a 2 = 1.)}

(The above is the structure when _{a 2 = 2.)} The separator for a non-aqueous electrolyte battery according to any one of claims 18 to 22, which satisfies at least one of the following coupling conditions A and B;
^{Bonding condition A: In R 1} in the general formula (1), the ^{carbon atom to which the −R 5-} M ⁺ is bonded and the carbon atom to which the amide group is bonded are adjacent to each other;
Coupling conditions B: In the general formula (1), in R ^2, the carbon atom to which the -R ^6- M carbon atoms and an amide ^{group +} is bonded is bonded are adjacent. The separator for a non-aqueous electrolyte battery according to any one of claims 18 to 23, wherein M ^{+ is an alkali metal cation.} The separator for a non-aqueous electrolyte battery according to any one of claims 16 to 24, wherein the inorganic filler contains alumina or barium sulfate. The separator for a non-aqueous electrolyte battery according to any one of claims 16 to 25, wherein the particle layer (II) contains 0.4 to 5.0 parts by mass of (a) a polyamide resin with respect to 100 parts by mass of the inorganic filler. The separator for a non-aqueous electrolyte battery according to any one of claims 16 to 26, wherein the particle layer (II) contains 0.5 to 5.0 parts by mass of a water-insoluble polymer with respect to 100 parts by mass of an inorganic filler. The separator for a non-aqueous electrolyte battery according to any one of claims 16 to 27, which has the particle layer (II) on one side of the porous membrane (I). A non-aqueous electrolyte battery in which a positive electrode and a negative electrode are laminated via a separator, wherein the separator is a separator for a non-aqueous electrolyte battery according to any one of claims 16 to 28.