WO2018101294A1

WO2018101294A1 - Conductive carbon material dispersion

Info

Publication number: WO2018101294A1
Application number: PCT/JP2017/042729
Authority: WO
Inventors: 辰也畑中; 佑紀柴野; 卓司吉本
Original assignee: 日産化学工業株式会社
Priority date: 2016-12-02
Filing date: 2017-11-29
Publication date: 2018-06-07
Also published as: JPWO2018101294A1; JP7081493B2; TW201833203A

Abstract

Provided is a conductive carbon material dispersion comprising a conductive carbon material and at least one defoaming agent selected from among acetylene-based surfactants, silicone-based surfactants, metal soap-based surfactants, and acrylic surfactants. The conductive carbon material dispersion can suppress the generation of bubbles in the conductive carbon material dispersion, can be uniformly applied, and can provide a uniform conductive thin film, even when a dispersant having a surfactant activity is used.

Description

Conductive carbon material dispersion

The present invention relates to a conductive carbon material dispersion, and more specifically, relates to a conductive carbon material dispersion containing a conductive carbon material and an antifoaming agent and suitable as a composition for a conductive thin film.

In recent years, development of high-performance batteries has been actively promoted in response to demands for reducing the size and weight of mobile electronic devices such as smartphones, digital cameras, and portable game machines, and secondary batteries that can be used repeatedly by charging. Demand is growing significantly.
Among them, a lithium ion secondary battery is a secondary battery that has been developed most vigorously at present because it has a high energy density and a high voltage and has no memory effect during charging and discharging.
In addition, the development of electric vehicles has been actively promoted due to recent efforts to deal with environmental problems, and higher performance has been demanded for secondary batteries as a power source.

By the way, a lithium ion secondary battery contains a positive electrode and a negative electrode capable of occluding and releasing lithium, and a separator interposed therebetween in a container, and an electrolyte solution (liquid in the case of a lithium ion polymer secondary battery) therein. It has a structure filled with a gel-like or all solid electrolyte instead of the electrolyte.
For the positive and negative electrodes, an active material capable of occluding and releasing lithium, a conductive material mainly composed of a carbon material, and a composition containing a polymer binder are generally applied on a current collector such as a copper foil or an aluminum foil. It is manufactured by doing. This binder is used to bond an active material and a conductive material, and further to the metal foil, and is a fluorine-based resin soluble in N-methylpyrrolidone (NMP) such as polyvinylidene fluoride (PVdF) or an olefin-based heavy polymer. Combined aqueous dispersions are commercially available.

As described above, the lithium ion secondary battery is also expected to be applied as a power source for electric vehicles and the like, and a longer life and safety than ever before are required.
However, the adhesive strength of the binder to the current collector cannot be said to be sufficient, and part of the active material or conductive material is peeled off from the current collector during the manufacturing process such as the cutting process or winding process of the electrode plate. However, this may cause a minute short circuit and a variation in battery capacity.
Furthermore, the contact resistance between the electrode mixture and the current collector increases due to the volume change of the electrode mixture due to the swelling of the binder due to the electrolytic solution and the volume change due to the lithium occlusion and release of the active material after long-term use. In addition, there is a problem that battery capacity is deteriorated due to part of the active material or conductive material peeling off from the current collector or dropping off, and further, there is a problem in terms of safety.
In particular, in recent years, development of active materials such as solid solution systems in the positive electrode system and alloy systems such as silicon in the negative electrode system is larger than the existing ones, and therefore the volume change due to charge and discharge is large. It can be said that peeling of the electrode mixture from the current collector is a problem to be solved immediately.

As an attempt to solve the above problem, a method of inserting a conductive binder layer between a current collector and an electrode mixture has been developed.
For example, in Patent Document 1, a conductive carbon material is dispersed by using a surfactant-containing polymer having an oxazoline group as a dispersant, and a conductive thin film (hereinafter, referred to as a conductive thin film) obtained from this conductive carbon material dispersion. Current collector (hereinafter also referred to as a composite current collector) can reduce the contact resistance between the current collector and the electrode mixture, and reduce the capacity during high-speed discharge. It has been shown that the degradation of the battery can also be suppressed.

However, when using the conductive carbon material dispersion liquid as described above, bubbles are easily generated in the coating process, and the operation becomes complicated when the coating liquid is manufactured. As a result, paint defects such as repelling derived from bubbles were generated, and new problems such as the point that the appearance of the paint and the performance as a battery were significantly impaired occurred. In particular, in an aqueous dispersion, when carbon nanotubes are used as the conductive carbon material, a polymer having an oxazoline group is used as the dispersant, and the conductive binding layer has a low basis weight, this problem becomes significant.

In order to solve these problems, attempts have been made to suppress the generation of bubbles by adding an antifoaming agent to a conductive carbon material dispersion using a dispersing agent having a surface active action. However, the defoaming agent does not interact with the dispersing agent or conductive carbon material, and the conductive carbon material aggregates and cannot maintain a uniform dispersed state. As a result, a uniform conductive thin film cannot be prepared. There was a case.

Japanese Patent No. 5773097

The present invention has been made in view of such circumstances, and even when a dispersant having a surface-active action is used, the generation of bubbles in the conductive carbon material dispersion liquid can be suppressed and coating can be performed uniformly. An object of the present invention is to provide a conductive carbon material dispersion that can produce a uniform conductive thin film.

As a result of intensive studies to achieve the above object, the present inventors have determined that an acetylene-based surfactant, a silicone-based surfactant, a metal soap-based surfactant, and an acrylic interface with respect to a conductive carbon material. By adding at least one antifoaming agent selected from activators, it is possible to suppress the generation of bubbles, and in particular, by adding an acetylene-based surfactant, specifically a uniformly dispersed state of the conductive carbon material The present inventors have found that a conductive carbon material dispersion liquid that can suppress the generation of bubbles while maintaining the viscosity and can be applied uniformly is obtained.

That is, the present invention
1. It includes a conductive carbon material and one or more antifoaming agents selected from acetylene surfactants, silicone surfactants, metal soap surfactants, and acrylic surfactants. Conductive carbon material dispersion,
2. 1 conductive carbon material dispersion liquid in which the antifoaming agent contains an acetylene-based surfactant;
3. Furthermore, 1 or 2 conductive carbon material dispersion liquid containing the conductive carbon material dispersing agent which has surface active action, and a dispersion medium,
4). The conductive carbon material dispersion liquid according to any one of 1 to 3, wherein the conductive carbon material includes one or more selected from graphite, carbon black, and carbon nanotubes,
5). The conductive carbon material is a conductive carbon material dispersion liquid of any one of 1 to 4, wherein the conductive carbon material contains carbon nanotubes,
6). The dispersion medium is any one of 3 to 5 conductive carbon material dispersion liquid containing water,
7). The conductive carbon material dispersion liquid according to any one of 3 to 6, wherein the conductive carbon material dispersant contains a polymer having an oxazoline group in a side chain;
8). The conductive carbon material dispersion liquid of 7, wherein the polymer having an oxazoline group in the side chain is a polymer of an oxazoline monomer represented by the following formula (1):

(Wherein X represents a polymerizable carbon-carbon double bond-containing group, and R ¹ to R ⁴ each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or a carbon number of 6 Represents an aryl group having ˜20 or an aralkyl group having 7 to 20 carbon atoms.)
9. A conductive carbon material dispersion of 8, wherein the chain hydrocarbon group containing a polymerizable carbon-carbon double bond is an alkenyl group having 2 to 8 carbon atoms;
10. The oxazoline monomer is 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-4-ethyl-2-oxazoline, 2-vinyl-4-propyl-2-oxazoline, 2 -Vinyl-4-butyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-vinyl-5-ethyl-2-oxazoline, 2-vinyl-5-propyl-2-oxazoline, 2-vinyl -5-butyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-4-ethyl-2-oxazoline, 2-isopropenyl-4 -Propyl-2-oxazoline, 2-isopropenyl-4-butyl-2-oxazoline, 2-isopropenyl-5-methyl 1 selected from the group consisting of -2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline, 2-isopropenyl-5-propyl-2-oxazoline and 2-isopropenyl-5-butyl-2-oxazoline 8 conductive carbon material dispersions that are seeds or two or more kinds,
11. 10 conductive carbon material dispersions wherein the oxazoline monomer is 2-isopropenyl-2-oxazoline;
12 Any one of the conductive carbon material dispersions 1 to 11 containing a crosslinking agent;
13. 12 conductive carbon material dispersions, wherein the crosslinking agent comprises a compound that causes a crosslinking reaction with an oxazoline group,
14 A compound that undergoes a crosslinking reaction with the oxazoline group exhibits a crosslinking reactivity in the presence of an acid catalyst, a synthetic polymer metal salt and a natural polymer metal salt, and exhibits a crosslinking reactivity when heated. 13 conductive carbon material dispersions containing a compound selected from ammonium salts of molecules and ammonium salts of natural polymers,
15. 14 conductive substances, wherein the compound causing a crosslinking reaction with the oxazoline group includes a compound selected from lithium polyacrylate, sodium polyacrylate, ammonium polyacrylate, lithium carboxymethylcellulose, sodium carboxymethylcellulose, ammonium carboxymethylcellulose, and ammonium alginate. Carbon material dispersion,
16. 1 to 15 of a conductive carbon material dispersion containing a polymer to be a matrix,
17. A conductive binder layer obtained from the conductive carbon material dispersion liquid of any one of 1 to 16,
18. 17 conductive binder layers having a thickness of 5 μm or less,
19. 17 conductive binder layers having a thickness of 1 μm or less,
20. 17 conductive binder layers having a thickness of 0.5 μm or less,
21. A composite current collector for an electrode of an energy storage device, comprising: a current collecting substrate; and any one of conductive bonding layers 17 to 20 formed on the substrate,
22. An electrode for an energy storage device comprising a composite current collector for an electrode of 21 energy storage devices,
23. 22 energy storage device electrodes comprising 21 energy storage device electrode composite current collectors and an active material layer formed on the conductive binder layer of the composite current collectors,
24. An energy storage device comprising 22 or 23 electrodes for energy storage devices,
25. 24 energy storage devices which are lithium ion secondary batteries,
26. A method for producing a conductive carbon material dispersion liquid with suppressed foaming, comprising mixing a conductive carbon material, a conductive carbon material dispersant having a surface-active action, a dispersion medium, and an acetylene-based surfactant;
27. Provided is a method for defoaming a conductive carbon material dispersion, comprising mixing a conductive carbon material, a conductive carbon material dispersant having a surface active action, a dispersion medium, and an acetylene surfactant.

Since the conductive carbon material dispersion of the present invention is difficult to foam, its preparation and uniform coating are easy, and a uniform thin film can be easily obtained by coating the dispersion on a substrate.
Since the obtained thin film exhibits high conductivity, it is suitable for the production of a conductive thin film and not only provides a thin film with excellent adhesion to a substrate, but also efficiently by a wet method with good reproducibility. Since a thin film having a large area can be formed, it can be suitably used not only for energy storage devices but also for various applications such as various semiconductor materials and conductor materials.
In particular, since a conductive thin film having excellent adhesion to the current collector substrate can be formed, the conductive thin film for forming a conductive binder layer for joining the current collector substrate constituting the energy storage device electrode and the active material, etc. It is suitable as a composition for use.
By using this conductive binder layer, the electrical resistance of the energy storage device can be lowered, so that current can be taken out without causing a voltage drop, especially in applications that require a large current instantaneously, such as in electric vehicles. At the same time, the service life can be extended.

Hereinafter, the present invention will be described in more detail.
The conductive carbon material dispersion according to the present invention is one or two selected from conductive carbon materials, acetylene surfactants, silicone surfactants, metal soap surfactants, and acrylic surfactants. The above-mentioned antifoaming agent is included.
In particular, in consideration of maintaining the uniform dispersibility by suppressing aggregation of the conductive carbon material, an antifoaming agent containing an acetylene surfactant is preferable, and an antifoaming agent containing 50% by mass or more of an acetylene surfactant is preferable. Preferably, an antifoaming agent containing 80% by mass or more of an acetylenic surfactant is more preferable, and an antifoaming agent consisting of only an acetylenic surfactant (100% by mass) is optimal.
Further, in the conductive carbon material dispersion of the present invention, the amount of the antifoaming agent is not particularly limited, but while sufficiently exerting the foaming suppression effect, the aggregation of the conductive carbon material is suppressed. In view of maintaining uniform dispersibility, the content is preferably 0.001 to 1.0 mass%, more preferably 0.01 to 0.5 mass%, based on the entire dispersion.

Specific examples of the acetylene-based surfactant used as an antifoaming agent in the present invention are not particularly limited, but a surfactant containing an ethoxylated acetylene glycol represented by the following formula (A) is used. It is preferable to use it.

In the formula (A), R ⁵ to R ⁸ each independently represents an alkyl group having 1 to 10 carbon atoms, and n and m each independently represent an integer of 0 or more, but n + m = 0 to 40.
Specific examples of the alkyl group having 1 to 10 carbon atoms may be linear, branched, or cyclic. For example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec -Butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group and the like.

Specific examples of the acetylene glycol represented by the above formula (A) include 2,5,8,11-tetramethyl-6-dodecin-5,8-diol, 5,8-dimethyl-6-dodecin-5, 8-diol, 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 4,7-dimethyl-5-decyne-4,7-diol, 2,3,6,7-tetra Methyl-4-octyne-3,6-diol, 3,6-dimethyl-4-octyne-3,6-diol, 2,5-dimethyl-3-hexyne-2,5-diol, 2,4,7, Ethoxylate of 9-tetramethyl-5-decyne-4,7-diol (number of moles of ethylene oxide added: 1.3), 2,4,7,9-tetramethyl-5-decyne-4,7-diol Of ethoxylate (added moles of ethylene oxide) 4), Ethoxylated form of 3,6-dimethyl-4-octyne-3,6-diol (number of moles of ethylene oxide added: 4), 2,5,8,11-tetramethyl-6-dodecin-5,8 -Ethoxylated form of diol (ethylene oxide addition moles: 6) 2,4,7,9-tetramethyl-5-decyne-4,7-diol ethoxylated form (ethylene oxide addition moles: 10), 2 , 4,7,9-Tetramethyl-5-decyne-4,7-diol ethoxylate (ethylene oxide addition moles: 30), 3,6-dimethyl-4-octyne-3,6-diol ethoxyl (Emethylene oxide addition mole number: 20) etc. are mentioned, These may be used individually by 1 type, or may be used in combination of 2 or more type.

The acetylene-based surfactant that can be used in the present invention can also be obtained as a commercial product. Examples of such a commercial product include Olphine D-10PG (manufactured by Nissin Chemical Industry Co., Ltd., active ingredient 50 mass). %, Pale yellow liquid), Olphine E-1004 (manufactured by Nissin Chemical Industry Co., Ltd., active ingredient 100% by mass, pale yellow liquid), Olphine E-1010 (manufactured by Nissin Chemical Industry Co., Ltd., active ingredient 100% by mass) %, Pale yellow liquid), Olphine E-1020 (manufactured by Nissin Chemical Industry Co., Ltd., active ingredient 100% by mass, pale yellow liquid), Olphine E-1030W (manufactured by Nissin Chemical Industry Co., Ltd., active ingredient 75 masses) %, Light yellow liquid), Surfynol 420 (manufactured by Nissin Chemical Industry Co., Ltd., active ingredient 100 mass%, pale yellow viscous substance), Surfynol 440 (manufactured by Nissin Chemical Industry Co., Ltd., active ingredient 100 mass) %, Yellow viscous 稠体), SURFYNOL 104E (Nisshin Chemical Industry Co., Ltd., effective component 50 mass%, light yellow viscous 稠体), and the like.

The silicone surfactant used as an antifoaming agent in the present invention is not particularly limited, and may be linear, branched, or cyclic as long as it contains at least a silicone chain. Either a hydrophobic group or a hydrophilic group may be contained.
Specific examples of the hydrophobic group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group, n-hexyl group, n- Examples thereof include alkyl groups such as heptyl group, n-octyl group, n-nonyl group and n-decyl group; cyclic alkyl groups such as cyclohexyl group; aromatic hydrocarbon groups such as phenyl group.
Specific examples of hydrophilic groups include amino groups, thiol groups, hydroxyl groups, alkoxy groups, carboxylic acids, sulfonic acids, phosphoric acids, nitric acids and their organic and inorganic salts, ester groups, aldehyde groups, glycerol groups, heterocyclic rings. Groups and the like.

Specific examples of silicone surfactants include dimethyl silicone, methylphenyl silicone, chlorophenyl silicone, alkyl modified silicone, fluorine modified silicone, amino modified silicone, alcohol modified silicone, phenol modified silicone, carboxy modified silicone, epoxy modified silicone, fatty acid. Examples thereof include ester-modified silicone and polyether-modified silicone.

Silicone-based surfactants that can be used in the present invention can also be obtained as commercial products, such as BYK-300, BYK-301, BYK-302, BYK-306, BYK-307, BYK-310, BYK-313, BYK-320BYK-333, BYK-341, BYK-345, BYK-346, BYK-347, BYK-348, BYK-349 (above trade names, manufactured by BYK Japan KK) , KM-80, KF-351A, KF-352A, KF-353, KF-354L, KF-355A, KF-615A, KF-945, KF-640, KF-642, KF-643, KF-6020, X -22-4515, KF-6011, KF-6012, KF-6015, KF-6017 (Manufactured by Gaku Kogyo Co., Ltd.), SH-28PA, SH8400, SH-190, SF-8428 (trade name, manufactured by Toray Dow Corning Co., Ltd.), Polyflow KL-245, Polyflow KL-270, Polyflow KL-100 (The trade name, manufactured by Kyoeisha Chemical Co., Ltd.), Silface SAG002, Silface SAG005, Silface SAG0085 (The trade name, manufactured by Nissin Chemical Industry Co., Ltd.) and the like.

The metal soap surfactant used as an antifoaming agent in the present invention is not particularly limited, and includes any of linear, branched, and cyclic containing at least a polyvalent metal ion such as calcium and magnesium. It may be a structured metal soap.
More specifically, fatty acids having 12 to 22 carbon atoms such as aluminum stearate, manganese stearate, cobalt stearate, copper stearate, iron stearate, nickel stearate, calcium stearate, zinc laurate, magnesium behenate and the like And salts with metals (alkaline earth metals, aluminum, manganese, cobalt, copper, iron, zinc, nickel, etc.).
The metal soap-based surfactant that can be used in the present invention can also be obtained as a commercial product. Examples of such a commercial product include Nopco NXZ (trade name, manufactured by San Nopco Co., Ltd.).

The acrylic surfactant used as an antifoaming agent in the present invention is not particularly limited as long as it is a polymer obtained by polymerizing at least an acrylic monomer, but is obtained by polymerizing at least an alkyl acrylate. The polymer obtained is preferably a polymer obtained by polymerizing an alkyl acrylate having at least 2 to 9 carbon atoms in the alkyl group.
Specific examples of the acrylic acid alkyl ester having 2 to 9 carbon atoms in the alkyl group include acrylic acid ethyl ester, acrylic acid n-propyl ester, acrylic acid isopropyl ester, acrylic acid n-butyl ester, acrylic acid isobutyl ester, Examples thereof include t-butyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, isononyl acrylate and the like.

The acrylic surfactant that can be used in the present invention can also be obtained as a commercially available product. Examples of such commercially available products include 1970, 230, LF-1980, LF-1982 (-50), LF- 1983 (-50), LF-1984 (-50), LHP-95, LHP-96, UVX-35, UVX-36, UVX-270, UVX-271, UVX-272, AQ-7120, AQ-7130 ( As mentioned above, trade names manufactured by Enomoto Kasei Co., Ltd.), BYK-350, BYK-352, BYK-354, BYK-355, BYK-358, BYK-380, BYK-381, BYK-392 (above, Big Chemie Japan ( Product name), Polyflow No. 7, Polyflow No. 50E, Polyflow No. 85, Polyflow No. 90, polyflow no. 95, Florene AC-220F, Polyflow KL-800 (above, trade name, manufactured by Kyoeisha Chemical Co., Ltd.), New Coal series (produced by Nippon Emulsifier Co., Ltd.)

The conductive carbon material is not particularly limited, but when used for forming a binding layer of a secondary battery, a fibrous conductive carbon material, a layered conductive carbon material, a particulate conductive carbon material. Is preferred. These conductive carbon materials can be used alone or in combination of two or more.

Specific examples of the fibrous conductive carbon material include carbon nanotubes (CNT) and carbon nanofibers (CNF). CNT is preferable from the viewpoint of conductivity, dispersibility, availability, and the like.
CNTs are generally produced by arc discharge, chemical vapor deposition (CVD), laser ablation, etc., but the CNTs used in the present invention may be obtained by any method. . In addition, single-walled CNT (hereinafter referred to as SWCNT) in which one carbon film (graphene sheet) is wound in a cylindrical shape and two-layered CNT in which two graphene sheets are wound in a concentric shape. (Hereinafter referred to as DWCNT) and multi-layer CNT (hereinafter referred to as MWCNT) in which a plurality of graphene sheets are concentrically wound, but in the present invention, SWCNT, DWCNT, and MWCNT are each a single unit, Or a combination of several can be used.
In addition, when producing SWCNT, DWCNT and MWCNT by the above method, catalyst metals such as nickel, iron, cobalt, yttrium may remain, so that removal or purification of this impurity may be required. is there. In order to remove impurities, it is effective to perform ultrasonic treatment together with acid treatment with nitric acid, sulfuric acid or the like. However, acid treatment with nitric acid, sulfuric acid or the like destroys the π-conjugated system constituting CNT and may impair the original characteristics of CNT. Therefore, it is desirable to purify and use under appropriate conditions.

Specific examples of CNTs that can be used in the present invention include spar gloss CNT (made by National Research and Development Corporation, Shinshin Energy and Industrial Technology Development Organization), eDIPS-CNT (made by National Research and Development Corporation, Shinshin Energy and Industrial Technology Development Organization). ], SWNT series [made by Meijo Nanocarbon Co., Ltd .: trade name], VGCF series [made by Showa Denko Co., Ltd .: trade name], FloTube series [made by CNano Technology Co., Ltd .: trade name], AMC [Ube Industries, Ltd.] Manufactured: trade name], NANOCYL NC7000 series [manufactured by Nanocyl. SA Ltd .: trade name], Baytubes [manufactured by BAYER: trade name], GRAPHISTRENGTH [manufactured by Arkema: trade name], MWNT7 [Hodogaya Chemical Co., Ltd. ): Product name], Hyperion CNT [Hyperion® Catalysis® International: product name].

Specific examples of the layered conductive carbon material include graphite and graphene. The graphite is not particularly limited, and various commercially available graphites can be used.
Graphene is a sheet of sp2 bonded carbon atoms with a thickness of 1 atom, and has a hexagonal lattice structure like a honeycomb made of carbon atoms and their bonds, and its thickness is about 0.38 nm. It is said. In addition to commercially available graphene oxide, graphene oxide obtained by processing graphite by the Hummers method may be used.

Specific examples of the particulate conductive carbon material include carbon black such as furnace black, channel black, acetylene black, and thermal black. These carbon blacks are not particularly limited, and various commercially available carbon blacks can be used, and the particle diameter is preferably 5 to 500 nm.

Solvents include pure water; ethers such as tetrahydrofuran (THF), diethyl ether, 1,2-dimethoxyethane (DME); halogenated hydrocarbons such as methylene chloride, chloroform, 1,2-dichloroethane; N, N Amides such as dimethylformamide (DMF), N, N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP); ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone; methanol, ethanol, Alcohols such as isopropanol and n-propanol; aliphatic hydrocarbons such as n-heptane, n-hexane and cyclohexane; aromatic hydrocarbons such as benzene, toluene, xylene and ethylbenzene; ethylene glycol monoethyl ether, ethylene glycol Glycol ethers such as coal monobutyl ether and propylene glycol monomethyl ether; organic solvents such as glycols such as ethylene glycol and propylene glycol can be used alone or in combination of two or more, but they are inexpensive and safe. From the viewpoint of high performance and low environmental burden, a solvent containing at least pure water is preferable, and a pure water single solvent is more preferable.

The conductive carbon material dispersant used in the present invention is not particularly limited as long as the conductive carbon material can be dispersed in a solvent. However, the conductive thin film obtained by drying can have strength. A polymer dispersant having a surface active action is preferred.

Specific examples of the polymeric dispersant having a surface active action include oxazoline polymers; polyalkylene glycols such as polyethylene glycol and polypropylene glycol; polyacrylamide; polystyrene sulfonic acid; poly (meth) acrylic acid, poly (meth) acrylic Poly (meth) acrylic acid derivatives such as sodium acid and ammonium poly (meth) acrylate; polyvinyl alcohol derivatives such as polyvinyl alcohol and polyvinyl acetal; cellulose derivatives such as methylcellulose, carboxycellulose and hydroxymethylcellulose; starch, lignin sulfonate, Natural polymers such as sodium alginate and derivatives thereof, copolymers of polymerizable monomers that are constituent units of these polymers, or copolymers with other monomers Examples include phase transfer catalysts such as crown ethers, etc., but when used for forming a binding layer of a secondary battery, viewpoints such as dispersibility, solubility, and adhesion to a current collector substrate To oxazoline polymers are preferred.

The oxazoline polymer is not particularly limited as long as it is a polymer in which an oxazoline group is bonded directly to a repeating unit constituting the main chain or via a spacer group such as an alkylene group. A repeating unit bonded to a polymer main chain or a spacer group at the 2-position of the oxazoline ring, obtained by radical polymerization of an oxazoline monomer having a polymerizable carbon-carbon double bond-containing group at the 2-position as shown in 1) A vinyl polymer having an oxazoline group in the side chain is preferred.

X represents a polymerizable carbon-carbon double bond-containing group, and R ¹ to R ⁴ are independently of each other a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or a 6 to 20 carbon atoms. An aryl group or an aralkyl group having 7 to 20 carbon atoms is represented.
The polymerizable carbon-carbon double bond-containing group of the oxazoline monomer is not particularly limited as long as it contains a polymerizable carbon-carbon double bond, but a chain containing a polymerizable carbon-carbon double bond. And a hydrocarbon group having 2 to 8 carbon atoms such as vinyl group, allyl group and isopropenyl group is preferable.
Here, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
The alkyl group having 1 to 5 carbon atoms may be linear, branched or cyclic, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group. Tert-butyl group, n-pentyl group, cyclohexyl group and the like.
Specific examples of the aryl group having 6 to 20 carbon atoms include phenyl group, xylyl group, tolyl group, biphenyl group, naphthyl group and the like.
Specific examples of the aralkyl group having 7 to 20 carbon atoms include benzyl group, phenylethyl group, phenylcyclohexyl group and the like.

Specific examples of the oxazoline monomer having a polymerizable carbon-carbon double bond-containing group at the 2-position represented by the formula (1) include 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-4-ethyl-2-oxazoline, 2-vinyl-4-propyl-2-oxazoline, 2-vinyl-4-butyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2- Vinyl-5-ethyl-2-oxazoline, 2-vinyl-5-propyl-2-oxazoline, 2-vinyl-5-butyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-4- Methyl-2-oxazoline, 2-isopropenyl-4-ethyl-2-oxazoline, 2-isopropenyl-4-propyl-2-oxazoline, 2- Sopropenyl-4-butyl-2-oxazoline, 2-isopropenyl-5-methyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline, 2-isopropenyl-5-propyl-2-oxazoline, 2 -Isopropenyl-5-butyl-2-oxazoline and the like can be mentioned, but 2-isopropenyl-2-oxazoline is preferable from the viewpoint of availability.

In consideration of preparing the conductive carbon material dispersant using an aqueous solvent, the oxazoline polymer is also preferably water-soluble.
Such a water-soluble oxazoline polymer may be a homopolymer of the oxazoline monomer represented by the above formula (1), but has a oxazoline monomer and a hydrophilic functional group in order to further enhance the solubility in water (meta ) It is preferable to be obtained by radical polymerization of at least two monomers with an acrylate monomer.

Specific examples of the (meth) acrylic monomer having a hydrophilic functional group include (meth) acrylic acid, 2-hydroxyethyl acrylate, methoxypolyethylene glycol acrylate, monoesterified product of acrylic acid and polyethylene glycol, acrylic acid 2-aminoethyl and its salt, 2-hydroxyethyl methacrylate, methoxypolyethylene glycol methacrylate, monoesterified product of methacrylic acid and polyethylene glycol, 2-aminoethyl methacrylate and its salt, sodium (meth) acrylate, ( Ammonium methacrylate, (meth) acrylonitrile, (meth) acrylamide, N-methylol (meth) acrylamide, N- (2-hydroxyethyl) (meth) acrylamide, sodium styrenesulfonate, etc. The like, which may be used singly or may be used in combination of two or more. Among these, (meth) acrylic acid methoxypolyethylene glycol and monoesterified products of (meth) acrylic acid and polyethylene glycol are preferable.

In the present invention, the oxazoline monomer and other monomers other than the (meth) acrylic monomer having a hydrophilic functional group are used in combination as long as the conductive carbon material dispersibility of the obtained oxazoline polymer is not adversely affected. be able to.
Specific examples of other monomers include methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, stearyl (meth) acrylate, (meth) acrylic. (Meth) acrylic acid ester monomers such as perfluoroethyl acid and phenyl (meth) acrylate; α-olefin monomers such as ethylene, propylene, butene and pentene; haloolefins such as vinyl chloride, vinylidene chloride and vinyl fluoride Monomers: Styrene monomers such as styrene and α-methyl styrene; Vinyl ester monomers such as vinyl acetate and vinyl propionate; Vinyl ether monomers such as methyl vinyl ether and ethyl vinyl ether, and the like. But two or more A combination of the above may also be used.

In the monomer component used in the production of the oxazoline polymer used in the present invention, the content of the oxazoline monomer is preferably 10% by mass or more, more preferably 20% by mass or more from the viewpoint of further increasing the CNT dispersibility of the obtained oxazoline polymer. Preferably, 30% by mass or more is even more preferable. In addition, the upper limit of the content rate of the oxazoline monomer in a monomer component is 100 mass%, and the homopolymer of an oxazoline monomer is obtained in this case.
On the other hand, the content of the (meth) acrylic monomer having a hydrophilic functional group in the monomer component is preferably 10% by mass or more, more preferably 20% by mass or more from the viewpoint of further increasing the water solubility of the obtained oxazoline polymer. 30% by mass or more is even more preferable.
In addition, as described above, the content of other monomers in the monomer component is a range that does not affect the CNT dispersibility of the obtained oxazoline polymer, and since it varies depending on the type, it cannot be determined unconditionally. What is necessary is just to set suitably in the range of 5-95 mass%, Preferably it is 10-90 mass%.

The average molecular weight of the oxazoline polymer is not particularly limited, but the weight average molecular weight is preferably 1,000 to 2,000,000. When the weight average molecular weight of the polymer is less than 1,000, there is a possibility that the dispersibility of the conductive carbon material is remarkably lowered or the dispersibility is not exhibited. On the other hand, if the weight average molecular weight exceeds 2,000,000, handling in the dispersion treatment may become extremely difficult. An oxazoline polymer having a weight average molecular weight of 2,000 to 1,000,000 is more preferable.
In addition, the weight average molecular weight in this invention is a measured value (polystyrene conversion) by gel permeation chromatography.

The oxazoline polymer that can be used in the present invention can be synthesized by a conventional radical polymerization of the above-mentioned monomers, but can also be obtained as a commercial product, and as such a commercial product, for example, Epocross WS-300 (Manufactured by Nippon Shokubai Co., Ltd., solid content concentration 10% by mass, aqueous solution), Epocross WS-700 (manufactured by Nippon Shokubai Co., Ltd., solid content concentration 25% by mass, aqueous solution), Epocross WS-500 (manufactured by Nippon Shokubai Co., Ltd.) Manufactured, solid content concentration 39% by mass, water / 1-methoxy-2-propanol solution), Poly (2-ethyl-2-oxazoline) (Aldrich), Poly (2-ethyl-2-oxazoline) (AlfaAesar), Poly (2-ethyl-2-oxazole) (VWR International, LLC) etc. Is mentioned.
In addition, when it is marketed as a solution, it may be used as it is, or it may be used after substituting with the target solvent.

In the present invention, the mixing ratio of the conductive carbon material dispersant to the conductive carbon material can be about 100: 1 to 1: 100 by mass ratio.
The concentration of the surfactant in the dispersion is not particularly limited as long as the conductive carbon material can be dispersed in a solvent. In the present invention, the concentration of the surfactant is 0.001 to 50. It is preferably about mass%, more preferably about 0.01 to 40 mass%.
Furthermore, the concentration of the conductive carbon material in the dispersion changes in the mechanical, electrical, and thermal characteristics required for the thin film, and at least a part of the conductive carbon material is isolated and dispersed. In the present invention, it is preferably about 0.001 to 50% by mass, more preferably about 0.01 to 40% by mass, and more preferably 0.02 to More preferably, it is about 30% by mass.

The conductive carbon material dispersion of the present invention may contain a crosslinking agent that is soluble in the above-described solvent. The crosslinking agent may be either a compound that causes a crosslinking reaction with the dispersant to be used or a compound that self-crosslinks, but reacts with the dispersant to form a crosslinked structure from the viewpoint of further improving the solvent resistance of the resulting thin film. A crosslinking agent is preferred.

As the compound that causes a crosslinking reaction with the dispersant, for example, if the dispersant is an oxazoline polymer, a functional group having reactivity with an oxazoline group such as a carboxyl group, a hydroxyl group, a thiol group, an amino group, a sulfinic acid group, and an epoxy group. Although it will not specifically limit if it is a compound which has two or more groups, The compound which has two or more carboxyl groups is preferable. In addition, a compound having a functional group that causes a crosslinking reaction by heating during thin film formation or in the presence of an acid catalyst, such as a sodium salt, potassium salt, lithium salt, or ammonium salt of a carboxylic acid is also crosslinked. It can be used as an agent.
Specific examples of these compounds include metal salts of synthetic polymers such as polyacrylic acid and copolymers thereof and natural polymers such as carboxymethylcellulose and alginic acid that exhibit crosslinking reactivity in the presence of an acid catalyst, and crosslinking reaction by heating. Examples include ammonium salts of the above-described synthetic polymers and natural polymers that exhibit the properties, in particular, sodium polyacrylate, lithium polyacrylate, which exhibit crosslinking reactivity in the presence of an acid catalyst or under heating conditions, Ammonium polyacrylate, sodium carboxymethyl cellulose, lithium carboxymethyl cellulose, carboxymethyl cellulose ammonium and the like are preferable.

The compound that causes a crosslinking reaction with the oxazoline group can also be obtained as a commercial product. Examples of such a commercial product include sodium polyacrylate (manufactured by Wako Pure Chemical Industries, Ltd., degree of polymerization 2,700). -7,500), sodium carboxymethylcellulose (manufactured by Wako Pure Chemical Industries, Ltd.), sodium alginate (manufactured by Kanto Chemical Co., Ltd., deer grade 1), Aron A-30 (ammonium polyacrylate, Toagosei Co., Ltd.) Manufactured, solid content concentration 32% by mass, aqueous solution), DN-800H (carboxymethyl cellulose ammonium, manufactured by Daicel Finechem Co., Ltd.), ammonium alginate (produced by Kimika Co., Ltd.), and the like.

Examples of the self-crosslinking compound include an aldehyde group, an epoxy group, a vinyl group, an isocyanate group, an alkoxy group, and a carboxyl group with respect to a hydroxyl group, an aldehyde group, an amino group, an isocyanate group, an epoxy group, and an amino group. Compounds that have crosslinkable functional groups that react with each other in the same molecule, such as isocyanate groups and aldehyde groups, hydroxyl groups that react with the same crosslinkable functional groups (dehydration condensation), mercapto groups (disulfide bonds), esters And compounds having a group (Claisen condensation), a silanol group (dehydration condensation), a vinyl group, an acrylic group, and the like.
Specific examples of the self-crosslinking compound include polyfunctional acrylate that exhibits crosslinking reactivity in the presence of an acid catalyst, tetraalkoxysilane, a monomer having a blocked isocyanate group, and at least one of a hydroxyl group, a carboxylic acid, and an amino group. Examples include monomer block copolymers.

Such a self-crosslinking crosslinking agent can also be obtained as a commercial product. Examples of such a commercial product include A-9300 (ethoxylated isocyanuric acid triacrylate, Shin-Nakamura Chemical ( ), A-GLY-9E (Ethoxylatedｉｎglycerine triacrylate (EO9 mol), Shin-Nakamura Chemical Co., Ltd.), A-TMMT (pentaerythritol tetraacrylate, Shin-Nakamura Chemical Co., Ltd.), tetraalkoxysilane In the case of tetramethoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.), tetraethoxysilane (manufactured by Toyoko Chemical Co., Ltd.), and polymers having a blocked isocyanate group, Elastron series E-37, H-3, H38, BAP, NEW BAP-15, C-52, F-2 9, W-11P, MF-9, MF-25K (Daiichi Kogyo Seiyaku Co., Ltd.).

Each of the above-mentioned crosslinking agents may be used alone or in combination of two or more.
The addition amount of the crosslinking agent varies depending on the solvent used, the substrate used, the required viscosity, the required film shape, etc., but is preferably 0.001 to 80% by mass with respect to the dispersant, Is more preferably from 50 to 50% by mass, and even more preferably from 0.05 to 40% by mass.
In the present invention, as a catalyst for accelerating the crosslinking reaction, p-toluenesulfonic acid, trifluoromethanesulfonic acid, pyridinium p-toluenesulfonic acid, salicylic acid, sulfosalicylic acid, citric acid, benzoic acid, hydroxybenzoic acid, naphthalenecarboxylic acid And / or a thermal acid generator such as 2,4,4,6-tetrabromocyclohexadienone, benzoin tosylate, 2-nitrobenzyl tosylate, and organic sulfonic acid alkyl ester can be added. .
The addition amount of the catalyst is 0.0001 to 20% by mass, preferably 0.0005 to 10% by mass, and more preferably 0.001 to 3% by mass with respect to the dispersant.

Furthermore, a polymer serving as a matrix may be added to the conductive carbon material dispersion of the present invention.
Examples of the matrix polymer include polyvinylidene fluoride (PVdF), polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, vinylidene fluoride-hexafluoropropylene copolymer [P (VDF-HFP)], Fluorine resin such as vinylidene fluoride-trichloroethylene copolymer [P (VDF-CTFE)], polyvinyl pyrrolidone, ethylene-propylene-diene terpolymer, PE (polyethylene), PP (polypropylene), Polyolefin resins such as EVA (ethylene-vinyl acetate copolymer), EEA (ethylene-ethyl acrylate copolymer); PS (polystyrene), HIPS (high impact polystyrene), AS (acrylonitrile-styrene copolymer), ABS (Acry Polystyrene resins such as nitrile-butadiene-styrene copolymer), MS (methyl methacrylate-styrene copolymer), styrene-butadiene rubber; polycarbonate resin; vinyl chloride resin; polyamide resin; polyimide resin; (Meth) acrylic resins such as PMMA (polymethyl methacrylate); PET (polyethylene terephthalate), polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, PLA (polylactic acid), poly-3-hydroxybutyric acid, polycaprolactone, poly Polyethylene resins such as butylene succinate and polyethylene succinate / adipate; polyphenylene ether resin; modified polyphenylene ether resin; polyacetal resin; polysulfone resin Polyphenylene sulfide resin; polyvinyl alcohol resin; polyglycolic acid; modified starch; cellulose acetate, carboxymethyl cellulose, cellulose triacetate; chitin, chitosan; thermoplastic resin such as lignin, emeraldine base that is polyaniline and its half-oxidized body; polythiophene; Polypyrrole; polyphenylene vinylene; polyphenylene; conductive polymer such as polyacetylene; and epoxy resin; urethane acrylate; phenol resin; melamine resin; urea resin; thermosetting resin such as alkyd resin; In the conductive carbon material dispersion liquid of the present invention, it is preferable to use water as a solvent, so that the matrix polymer is also water-soluble, such as sodium polyacrylate, calcium carbonate. Examples thereof include sodium boxymethylcellulose, water-soluble cellulose ether, sodium alginate, polyvinyl alcohol, polystyrene sulfonic acid, polyethylene glycol and the like, and particularly, sodium polyacrylate and sodium carboxymethylcellulose are preferable.

The matrix polymer can also be obtained as a commercial product. Examples of such a commercial product include sodium polyacrylate (manufactured by Wako Pure Chemical Industries, Ltd., degree of polymerization 2,700 to 7,500), carboxy Sodium methylcellulose (manufactured by Wako Pure Chemical Industries, Ltd.), sodium alginate (manufactured by Kanto Chemical Co., Ltd., deer grade 1), Metrol's SH series (hydroxypropylmethylcellulose, Shin-Etsu Chemical Co., Ltd.), Metrolose SE series (hydroxyl) Ethyl methyl cellulose, manufactured by Shin-Etsu Chemical Co., Ltd.), JC-25 (completely saponified polyvinyl alcohol, manufactured by Nippon Vineyard Poval Co., Ltd.), JM-17 (intermediate saponified polyvinyl alcohol, Nippon Vinegared / Poval) Manufactured by Co., Ltd.), JP-03 (partially saponified polyvinyl alcohol, Nippon Vinegar Poval) Ltd.), polystyrene sulfonic acid (Aldrich Corp., solid concentration 18 wt%, aqueous solution), and the like.
The content of the matrix polymer is not particularly limited, but is preferably about 0.0001 to 99% by mass, more preferably about 0.001 to 90% by mass in the dispersion. .

The method for preparing the conductive carbon material dispersion of the present invention is arbitrary, and the surfactant, the conductive carbon material, the solvent and the antifoaming agent, and the cross-linking agent and matrix polymer used as necessary are in any order. A dispersion may be prepared by mixing.
At this time, it is preferable to disperse a mixture of a surfactant, a conductive carbon material and a solvent, and this treatment can further improve the dispersion ratio of the conductive carbon material. Examples of the dispersion treatment include mechanical treatment, wet treatment using a ball mill, bead mill, jet mill, etc., and ultrasonic treatment using a bath-type or probe-type sonicator. In particular, wet treatment using a jet mill. Or sonication is preferred.
An antifoaming agent is preferable because it can suppress foaming during the dispersion treatment by adding it before the dispersion treatment, but it may inhibit the dispersion of the conductive carbon material by the surfactant. It may be added after processing.
Moreover, you may add a crosslinking agent and a matrix polymer, after preparing the dispersion liquid containing components other than these.
In the conductive carbon material dispersion prepared as described above, it is presumed that the dispersant is physically adsorbed on the surface of the conductive carbon material to form a composite.

In producing a conductive thin film using the conductive carbon material dispersion liquid of the present invention, the conductive carbon material dispersion liquid (composition for conductive thin film) described above is applied onto a substrate or a product on which a thin film is to be formed. This can be produced by natural or heat drying to form a conductive binder layer.
The substrate and the formed product are not particularly limited. For example, metals such as copper, aluminum, nickel, gold, silver, and alloys thereof; carbon materials; metal oxides; conductive polymers; Synthetic polymers such as tarate, polypropylene and polyimide; natural polymers such as cellulose and chitosan can be used.
The thickness is not particularly limited, but is preferably 1 to 100 μm in the present invention.

The conductive thin film obtained from the conductive carbon material dispersion of the present invention is interposed between the current collecting substrate constituting the electrode of the energy storage device and the active material layer, and is formed into a conductive binding layer that binds both. Especially suitable.
In the present invention, as the energy storage device, various energy storage devices such as an electric double layer capacitor, a lithium secondary battery, a lithium ion secondary battery, a proton polymer battery, a nickel metal hydride battery, an aluminum solid capacitor, an electrolytic capacitor, and a lead storage battery. Although mentioned, the electroconductive thin film obtained from the electroconductive carbon material dispersion liquid of this invention can be applied suitably for the electrode of an electrical double layer capacitor and a lithium ion secondary battery especially.

In preparing an electrode using the composition for conductive thin film of the present invention, it is preferable to first prepare a composite current collector comprising a current collector substrate and a conductive binder layer. In this composite current collector, the conductive carbon material dispersion liquid (composition for conductive thin film) described above is applied onto a current collector substrate, and this is naturally or heat-dried to form a conductive binder layer. Can be produced.
The current collecting substrate may be appropriately selected from those conventionally used as a current collecting substrate for electrodes for energy storage devices. For example, copper, aluminum, nickel, gold, silver, alloys thereof, carbon materials, metals A thin film such as an oxide or a conductive polymer can be used.
The thickness is not particularly limited, but is preferably 1 to 100 μm in the present invention.

The thickness of the conductive binder layer in the present invention is preferably 5 μm or less, more preferably 1 μm or less, in consideration of improving the energy density of the battery and reducing the bulk resistance of the conductive binder layer. 5 μm or less is even more preferable.
The thickness of the conductive binder layer can be calculated by observing the cross section of the conductive binder layer with a scanning microscope (hereinafter referred to as SEM) or by dividing the basis weight by the specific gravity of the conductive binder layer. it can.
The cross section of the conductive binder layer can be obtained, for example, by tearing the composite current collector or processing with an ion beam.

The basis weight is the ratio of the mass (g) of the conductive binder layer to the area (m ² ) of the conductive binder layer, and when the conductive binder layer is formed in a pattern, the area is conductive It is the area of only the conductive binding layer, and does not include the area of the current collector substrate exposed between the conductive binding layers formed in a pattern.
For the mass of the conductive binder layer, for example, a test piece of an appropriate size is cut out from the composite current collector, its mass W0 is measured, and then the conductive binder layer is peeled off from the composite current collector. Measure the mass W1 after peeling off the conductive binder layer, and calculate from the difference (W0-W1), or measure the mass W2 of the current collector substrate in advance, and then form the conductive binder layer The mass W3 of the composite current collector measured can be measured and calculated from the difference (W3-W2).
As a method of peeling the conductive binder layer, for example, a method of immersing the conductive binder layer in a solvent in which the conductive binder layer is dissolved or swells and wiping the conductive binder layer with a cloth or the like is available. Can be mentioned.

The specific gravity of the conductive binder layer can be calculated, for example, by dividing the basis weight by the film thickness. Further, it can be measured by a bead replacement method, a tap density measurement or the like.

The film thickness can be adjusted by a known method. For example, when a conductive binder layer is formed by coating, the solid content concentration of the coating liquid (CNT-containing composition) for forming the conductive binder layer, the number of coating times, and the coating liquid inlet of the coating machine It can be adjusted by changing the clearance.
To increase the weight per unit area, increase the solid content concentration, increase the number of coatings, or increase the clearance. When it is desired to reduce the basis weight, the solid content concentration is decreased, the number of coatings is decreased, or the clearance is decreased.

Examples of coating methods include spin coating, dip coating, flow coating, ink jet, spray coating, bar coating, gravure coating, slit coating, roll coating, flexographic printing, transfer printing, Brush coating, blade coating method, air knife coating method, etc. are mentioned, but from the viewpoint of work efficiency etc., inkjet method, casting method, dip coating method, bar coating method, blade coating method, roll coating method, gravure coating method, A flexographic printing method and a spray coating method are suitable.
The temperature for drying by heating is also arbitrary, but is preferably about 50 to 200 ° C, more preferably about 80 to 150 ° C.

Furthermore, the energy storage device electrode can be produced by forming an active material layer on the conductive binding layer of the composite current collector.
Here, as an active material, the various active materials conventionally used for the electrode for energy storage devices can be used.
For example, in the case of a lithium secondary battery or a lithium ion secondary battery, a chalcogen compound capable of adsorbing / leaving lithium ions or a lithium ion-containing chalcogen compound, a polyanion compound, a simple substance of sulfur and a compound thereof may be used as a positive electrode active material. it can.
Specific examples of the chalcogen compound that can adsorb and desorb lithium ions include FeS ₂ , TiS ₂ , MoS ₂ , V ₂ O ₆ , V ₆ O ₁₃ , and MnO ₂ .
Specific examples of the lithium ion-containing chalcogen compound include LiCoO ₂ , LiMnO ₂ , LiMn ₂ O ₄ , LiMo ₂ O ₄ , LiV ₃ O ₈ , LiNiO ₂ , Li _x Ni _y M _1-y O ₂ (where M is Represents at least one metal element selected from Co, Mn, Ti, Cr, V, Al, Sn, Pb, and Zn, and 0.05 ≦ x ≦ 1.10, 0.5 ≦ y ≦ 1. 0) and the like.
Specific examples of the polyanionic compound include LiFePO ₄ .
Specific examples of the sulfur compound include Li ₂ S and rubeanic acid.

On the other hand, as the negative electrode active material constituting the negative electrode, at least one element selected from alkali metals, alkali alloys, and elements of Groups 4 to 15 of the periodic table that occlude / release lithium ions, oxides, sulfides, nitrides Or a carbon material capable of reversibly occluding and releasing lithium ions can be used.
Examples of the alkali metal include Li, Na, and K. Specific examples of the alkali metal alloy include metals Li, Li—Al, Li—Mg, Li—Al—Ni, Na, Na—Hg, and Na—Zn. Etc.
Specific examples of at least one element selected from Group 4 to 15 elements of the periodic table that store and release lithium ions include silicon, tin, aluminum, zinc, and arsenic.
Similarly, specific examples of the oxide include tin silicon oxide (SnSiO ₃ ), lithium bismuth oxide (Li ₃ BiO ₄ ), lithium zinc oxide (Li ₂ ZnO ₂ ), lithium titanium oxide (Li ₄ Ti ₅ O ₁₂ ), and the like. Is mentioned.
Similarly, specific examples of sulfides include lithium iron sulfide (Li _x FeS ₂ (0 ≦ x ≦ 3)), lithium copper sulfide (Li _x CuS (0 ≦ x ≦ 3)), and the like.
The same nitride, lithium-containing transition metal nitrides and the like, and specific examples _{_{thereof, Li x M y N (M}} = Co, Ni, Cu, 0 ≦ x ≦ 3,0 ≦ y ≦ 0.5) And lithium iron nitride (Li ₃ FeN ₄ ).
Specific examples of the carbon material capable of reversibly occluding and releasing lithium ions include graphite, carbon black, coke, glassy carbon, carbon fiber, carbon nanotube, or a sintered body thereof.

In the case of an electric double layer capacitor, a carbonaceous material can be used as an active material.
Specific examples of the carbonaceous material include activated carbon and the like, for example, activated carbon obtained by carbonizing a phenol resin and then activating treatment.

In addition to the above active material, a conductive additive can also be added to the electrode of the present invention. Specific examples of the conductive aid include carbon black, ketjen black, acetylene black, carbon whisker, carbon fiber, natural graphite, artificial graphite, titanium oxide, ruthenium oxide, aluminum, nickel and the like.

The active material layer can be formed by applying the electrode slurry containing the active material, the binder polymer, and, if necessary, the solvent described above onto the conductive binder layer and naturally or by heating and drying.
The binder polymer can be appropriately selected from known materials and used, for example, polyvinylidene fluoride (PVdF), polyvinylpyrrolidone, polytetrafluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, vinylidene fluoride- Hexafluoropropylene copolymer [P (VDF-HFP)], vinylidene fluoride-trichloroethylene copolymer [P (VDF-CTFE)], polyvinyl alcohol, polyimide, ethylene-propylene-diene ternary copolymer Examples thereof include conductive polymers such as coalescence, styrene-butadiene rubber, carboxymethyl cellulose (CMC), polyacrylic acid (PAA), and polyaniline.
The added amount of the binder polymer is preferably 0.1 to 20 parts by mass, particularly 1 to 10 parts by mass with respect to 100 parts by mass of the active material.
Examples of the solvent include those exemplified for the above oxazoline polymer, and may be appropriately selected according to the type of the binder, but in the case of a water-insoluble binder such as PVdF, NMP is preferable, and PAA In the case of a water-soluble binder such as water, water is preferred.

Examples of the method for applying the electrode slurry include the same method as that for the conductive binder layer forming composition described above.
The temperature for drying by heating is also arbitrary, but is preferably about 50 to 200 ° C, more preferably about 80 to 150 ° C.

An energy storage device according to the present invention includes the above-described electrodes, and more specifically, includes at least a pair of positive and negative electrodes, a separator interposed between these electrodes, and an electrolyte. At least one of the positive and negative electrodes is composed of the above-described electrode for energy storage device.
Since this energy storage device is characterized by the use of the above-mentioned electrode for energy storage device as an electrode, other device constituent members such as separators and electrolytes may be appropriately selected from known materials and used. it can.
Specific examples of the separator include a cellulose separator and a polyolefin separator.
The electrolyte may be either liquid or solid, and may be either aqueous or non-aqueous. The electrode for an energy storage device of the present invention is practically sufficient even when applied to a device using a non-aqueous electrolyte. Performance can be demonstrated.

Examples of the non-aqueous electrolyte include a non-aqueous electrolyte obtained by dissolving an electrolyte salt in a non-aqueous organic solvent.
Examples of electrolyte salts include lithium salts such as lithium tetrafluoroborate, lithium hexafluorophosphate, lithium perchlorate, and lithium trifluoromethanesulfonate; tetramethylammonium hexafluorophosphate, tetraethylammonium hexafluorophosphate, tetrapropylammonium hexa Examples thereof include quaternary ammonium salts such as fluorophosphate, methyltriethylammonium hexafluorophosphate, tetraethylammonium tetrafluoroborate, and tetraethylammonium perchlorate.
Examples of the non-aqueous organic solvent include alkylene carbonates such as propylene carbonate, ethylene carbonate, and butylene carbonate; dialkyl carbonates such as dimethyl carbonate, methyl ethyl carbonate, and diethyl carbonate; nitriles such as acetonitrile; and amides such as dimethylformamide. .

EXAMPLES Hereinafter, although a manufacture example, an Example, and a comparative example are given and this invention is demonstrated more concretely, this invention is not limited to the following Example. The measuring devices used are as follows.
(1) Probe-type ultrasonic irradiation device Device: manufactured by Hielscher Ultrasonics, UIP1000
(2) Wire bar coater (thin film production)
Equipment: PM-9050MC manufactured by SMT Co., Ltd.
(3) Select Roller Matsuo Sangyo Co., Ltd. OSP-30, OSP-13, OSP-8

[1] Preparation of precursor dispersion [Production Example 1-1]
Epocross WS-700 (produced by Nippon Shokubai Co., Ltd., solid concentration 25 mass%, weight average molecular weight 4 × 10 ⁴ , oxazoline group amount 4.5 mmol / g) 2.0 g which is an aqueous solution containing an oxazoline polymer, and distilled water 47.5 g was mixed, and further, 0.5 g of multi-walled CNT (“NC7000” manufactured by Nanocyl), which is a conductive carbon material, was mixed therewith. The obtained mixture was subjected to ultrasonic treatment at room temperature for 30 minutes using a probe type ultrasonic irradiation device to prepare a precursor dispersion A in which CNTs were uniformly dispersed.

[Production Example 1-2]
Aron A-30 (Toagosei Co., Ltd., solid concentration 31.6% by mass) 0.7 g which is an aqueous solution containing ammonium polyacrylate (PAA-NH ₄ ) and ammonium alginate (alginate NH ₄ ) ((stock ) 20 g of 1% aqueous solution of Kimika) and 29.3 g of distilled water were mixed. The obtained solution was mixed with 50 g of the precursor dispersion A of Production Example 1-1 to prepare a precursor dispersion B in which CNTs were uniformly dispersed.

[Production Example 1-3]
A precursor dispersion C was prepared in the same manner as in Production Example 1-1 except that the conductive carbon material was changed to 0.5 g of acetylene black (“DENKA BLACK” manufactured by Denki Kagaku Kogyo Co., Ltd.).

[Production Example 1-4]
A conductive precursor dispersion D was prepared in the same manner as in Production Example 1-2 except that the precursor dispersion A was changed to the precursor dispersion C.

[2] Preparation of conductive carbon material dispersion [Example 1-1]
50 g of the precursor dispersion B prepared in Production Example 1-2 and 25 mg of acetylene surfactant (antifoaming agent) Olphine E-1004 (manufactured by Nissin Chemical Industry Co., Ltd., solid content concentration: 100% by mass) are mixed. Thus, a conductive carbon material dispersion was prepared.

[Example 1-2]
Example 1-1, except that acetylene surfactant Olfine E-1004 was changed to 25 mg of acetylene surfactant Surfynol 420 (manufactured by Nissin Chemical Industry Co., Ltd., solid concentration 100 mass%). A conductive carbon material dispersion was prepared by the method described above.

[Example 1-3]
50 g of the precursor dispersion D prepared in Production Example 1-4 and 25 mg of acetylene surfactant Olfine E-1004 (manufactured by Nissin Chemical Industry Co., Ltd., solid content concentration: 100% by mass) are mixed to form conductive carbon. A material dispersion was prepared.

[Example 1-4]
Except for changing the acetylene surfactant Olphine E-1004 to 25 mg of acetylene surfactant Surfynol 420 (manufactured by Nissin Chemical Industry Co., Ltd., solid content concentration: 100% by mass), the same as in Example 1-3 A conductive carbon material dispersion was prepared by the method described above.

[Example 1-5]
Except for changing the acetylene surfactant Olphine E-1004 to 25 mg of a silicone antifoaming agent Polyflow KL100 (manufactured by Kyoeisha Chemical Co., Ltd., solid content concentration: 100% by mass), the same method as in Example 1-1. A conductive carbon material dispersion was prepared.

[Example 1-6]
The same method as in Example 1-1, except that the acetylene-based surfactant Olphine E-1004 was changed to 25 mg of a metal soap-based antifoaming agent Nopco NXZ (manufactured by San Nopco, solid content concentration 100% by mass). A conductive carbon material dispersion was prepared.

[Example 1-7]
Except for changing the acetylene surfactant Olphine E-1004 to 26.9 mg of acrylic antifoaming agent Polyflow KL800 (manufactured by Kyoeisha Chemical Co., Ltd., solid content concentration: 93 mass%) 26.9 mg, the same as Example 1-1 A conductive carbon material dispersion was prepared by the method.

[Comparative Example 1-1]
The same method as in Example 2-1, except that the acetylene surfactant Olfine E-1004 was changed to 25 mg of the polyether antifoam SN deformer 170 (manufactured by San Nopco, solid content concentration 100% by mass). A conductive carbon material dispersion was prepared.

[Comparative Example 1-2]
The same method as in Example 1-1, except that the acetylene surfactant Olphine E-1004 was changed to 25 mg of the polyether antifoam SN deformer 260 (manufactured by San Nopco, solid concentration 100% by mass). A conductive carbon material dispersion was prepared.

[Comparative Example 1-3]
Example 1-1 and Example 1-1 were used except that the acetylene surfactant Olfine E-1004 was changed to 25 mg of the polyether antifoam Disperse CC-438 (manufactured by NOF Corporation, solid content concentration: 100% by mass). A conductive carbon material dispersion was prepared in the same manner.

[Comparative Example 1-4]
Example 1-1 is the same as Example 1-1 except that the acetylene surfactant Olfine E-1004 was changed to 25 mg of a polyether antifoaming agent Distro CD-432 (manufactured by NOF Corporation, solid content concentration: 100% by mass). A conductive carbon material dispersion was prepared in the same manner.

[Comparative Example 1-5]
Example 1-1 and Example 1-1 except that the acetylene surfactant Olphine E-1004 was changed to 25 mg of a polyether antifoaming agent Disform CE-457 (manufactured by NOF Corporation, solid content concentration: 100% by mass). A conductive carbon material dispersion was prepared in the same manner.

[Comparative Example 1-6]
Example 1 except that the acetylene surfactant Olphine E-1004 was changed to 25 mg of a polyether antifoaming agent, an antifoaming agent PF-H (manufactured by Wako Pure Chemical Industries, Ltd., solid content concentration: 100% by mass). A conductive carbon material dispersion was prepared in the same manner as in -1.

[Comparative Example 1-7]
Example 1 except that the acetylene surfactant Olfine E-1004 was changed to 25 mg of a polyether antifoaming agent, an antifoaming agent PF-M (manufactured by Wako Pure Chemical Industries, Ltd., solid content concentration: 100% by mass). A conductive carbon material dispersion was prepared in the same manner as in -1.

[Comparative Example 1-8]
Example 2 except that the acetylene surfactant Orphine E-1004 was changed to 25 mg of a polyether antifoaming agent, an antifoaming agent PF-L (manufactured by Wako Pure Chemical Industries, Ltd., solid content concentration: 100% by mass). A conductive carbon material dispersion was prepared in the same manner as in -1.

[Comparative Example 1-9]
Example 1-1, except that the acetylene surfactant Olfine E-1004 was changed to 25 mg of the fluorine-based antifoaming agent Floren AO-82 (manufactured by San Nopco, solid concentration 1.8% by mass). A conductive carbon material dispersion was prepared by the method described above.

[Comparative Example 1-10]
Except that the acetylene surfactant Olphine E-1004 was changed to 25 mg of a polyether antifoam Disperse CD-432 (manufactured by NOF Corporation, solid content concentration 100% by mass), Example 1-3 and A conductive carbon material dispersion was prepared in the same manner.

[3] Evaluation of conductive carbon material dispersion [Example 2-1]
The conductive carbon material dispersion prepared in Example 1-1 was added to a screw tube (manufactured by Maruemu Co., Ltd., No. 8), and shaken vigorously for 30 seconds to generate bubbles. After standing for 300 seconds, the liquid state of the conductive carbon material dispersion and the amount of bubbles on the liquid surface were visually confirmed. As a result, the liquid state of the conductive carbon material dispersion was maintained, the bubbles disappeared, and the liquid surface was exposed.

[Example 2-2]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the conductive carbon material dispersion prepared in Example 1-2. As a result, the liquid state of the conductive carbon material dispersion was maintained, the bubbles disappeared, and the liquid surface was exposed.

[Example 2-3]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the conductive carbon material dispersion prepared in Example 1-3. As a result, the liquid state of the conductive carbon material dispersion was maintained, the bubbles disappeared, and the liquid surface was exposed.

[Example 2-4]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the conductive carbon material dispersion prepared in Example 1-4. As a result, the liquid state of the conductive carbon material dispersion was maintained, the bubbles disappeared, and the liquid surface was exposed.

[Example 2-5]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the conductive carbon material dispersion prepared in Example 1-5. As a result, although the liquid state of the conductive carbon material dispersion changed and the CNTs aggregated, the bubbles disappeared and the liquid surface was exposed.

[Example 2-6]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the conductive carbon material dispersion prepared in Example 1-6. As a result, although the liquid state of the conductive carbon material dispersion changed and aggregated, the bubbles disappeared and the liquid surface was exposed.

[Example 2-7]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the conductive carbon material dispersion prepared in Example 1-7. As a result, although the liquid state of the conductive carbon material dispersion changed and the CNTs aggregated, the bubbles disappeared and the liquid surface was exposed.

[Comparative Example 2-1]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the conductive carbon material dispersion prepared in Comparative Example 1-1. As a result, the liquid state of the conductive carbon material dispersion changed, the CNTs aggregated, and the liquid surface was covered with bubbles.

[Comparative Example 2-2]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the conductive carbon material dispersion prepared in Comparative Example 1-2. As a result, the liquid state of the conductive carbon material dispersion changed, the CNTs aggregated, and the liquid surface was covered with bubbles.

[Comparative Example 2-3]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the conductive carbon material dispersion prepared in Comparative Example 1-3. As a result, the liquid state of the conductive carbon material dispersion changed, the CNTs aggregated, and the liquid surface was covered with bubbles.

[Comparative Example 2-4]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the conductive carbon material dispersion prepared in Comparative Example 1-4. As a result, the liquid state of the conductive carbon material dispersion changed, the CNTs aggregated, and the liquid surface was covered with bubbles.

[Comparative Example 2-5]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the conductive carbon material dispersion prepared in Comparative Example 1-5. As a result, the liquid state of the conductive carbon material dispersion changed, the CNTs aggregated, and the liquid surface was covered with bubbles.

[Comparative Example 2-6]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the conductive carbon material dispersion prepared in Comparative Example 1-6. As a result, the liquid state of the conductive carbon material dispersion liquid was maintained, but the liquid surface was covered with bubbles.

[Comparative Example 2-7]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the conductive carbon material dispersion prepared in Comparative Example 1-7. As a result, the liquid state of the conductive carbon material dispersion liquid was maintained, but the liquid surface was covered with bubbles.

[Comparative Example 2-8]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the conductive carbon material dispersion prepared in Comparative Example 1-8. As a result, the liquid state of the conductive carbon material dispersion liquid was maintained, but the liquid surface was covered with bubbles.

[Comparative Example 2-9]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the conductive carbon material dispersion prepared in Comparative Example 1-9. As a result, the liquid state of the conductive carbon material dispersion changed, the CNTs aggregated, and the liquid surface was covered with bubbles.

[Comparative Example 2-10]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the conductive carbon material dispersion prepared in Comparative Example 1-10. As a result, the liquid state of the conductive carbon material dispersion changed, acetylene black aggregated, and the liquid surface was covered with bubbles.

[Comparative Example 2-11]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the precursor dispersion B prepared in Production Example 1-2. As a result, the liquid state of the conductive carbon material dispersion liquid was maintained, but the liquid surface was covered with bubbles.

[Comparative Example 2-12]
Evaluation was made in the same manner as in Example 2-1, except that the conductive carbon material dispersion was changed to the precursor dispersion D prepared in Production Example 1-4. As a result, the liquid state of the conductive carbon material dispersion liquid was maintained, but the liquid surface was covered with bubbles.
A summary of Examples 2-1 to 2-7 and Comparative Examples 2-1 to 2-12 is shown in Table 1.

As shown in Table 1, conductive carbon material dispersions prepared in Comparative Examples 2-1 to 2-8, 2-10 containing a polyether surfactant and Comparative Example 2-9 containing a fluorosurfactant In the conductive carbon material dispersion liquids prepared in Comparative Examples 2-11 and 12 to which no surfactant as a liquid or an antifoaming agent was added, when bubbles are generated, the bubbles do not disappear immediately.
On the other hand, Examples 2-1 to 2-4 containing an acetylene-based antifoaming agent, Examples 2-5 containing a silicone-based surfactant, Example 2-6 containing a metal soap-based antifoaming agent, acrylic-based antifoaming In the conductive carbon material dispersion prepared in Example 2-7 containing the agent, the bubbles disappear immediately.
Furthermore, the conductive carbon material dispersion prepared in Example 2-5 containing a silicone surfactant, Example 2-6 containing a metal soap antifoaming agent, and Example 2-7 containing an acrylic antifoaming agent Then, the bubbles disappear immediately, but the liquid state of the conductive carbon material dispersion changes and aggregates. In contrast, in the conductive carbon material dispersion liquid prepared in Examples 2-1 to 2-4 containing an acetylene-based antifoaming agent, the bubbles disappeared immediately and a uniform dispersion state can be maintained.

[4] Coating of conductive carbon material dispersion [Example 3-1]
The conductive carbon material dispersion prepared in Example 1-1 was uniformly spread on an aluminum foil (thickness 15 μm) with a wire bar coater (select roller: OSP-30), and then dried at 150 ° C. for 20 minutes. An aluminum foil (hereinafter referred to as a composite current collector) having a uniform conductive binder layer free from coating defects was obtained. The obtained composite current collector was cut into an area of 120 cm ² and weighed, and then washed with a 0.1 mol / L dilute hydrochloric acid aqueous solution to remove the conductive binder layer. As a result of measuring the mass of the remaining aluminum foil and dividing the mass change before and after the removal of the conductive binder layer by the area, the basis weight of the conductive binder layer was determined and found to be 268 mg / m ² .
Moreover, as a result of observing the cross section produced by tearing a composite electrical power collector by SEM, the film thickness was 0.199 micrometer. The specific gravity of the conductive binder obtained from these values was 1.35 g / cm ³ .

[Example 3-2]
A composite current collector was obtained in the same manner as in Example 3-1, except that the selection roller: OSP-30 was changed to the selection roller: OSP-13. As a result of obtaining the basis weight of the obtained conductive binder layer, it was 147 mg / m ² . The film thickness calculated from the basis weight and the specific gravity obtained in Example 3-1 was 0.109 μm.

[Example 3-3]
A composite current collector was obtained in the same manner as in Example 3-1, except that the selection roller: OSP-30 was changed to the selection roller: OSP-8. As a result of obtaining the basis weight of the obtained conductive binder layer, it was 93 mg / m ² . The film thickness calculated from the basis weight and the specific gravity obtained in Example 3-1 was 0.069 μm.

[Example 3-4]
A composite current collector was obtained in the same manner as in Example 3-1, except that 10 g of the conductive carbon material dispersion prepared in Example 1-1 was diluted by adding 50 g of pure water. As a result of obtaining the basis weight of the obtained conductive binder layer, it was 19 mg / m ² . The film thickness calculated from the basis weight and the specific gravity obtained in Example 3-1 was 0.014 μm.

Claims

It includes a conductive carbon material and one or more antifoaming agents selected from acetylene surfactants, silicone surfactants, metal soap surfactants, and acrylic surfactants. Conductive carbon material dispersion.
The conductive carbon material dispersion according to claim 1, wherein the antifoaming agent contains an acetylene surfactant.
The conductive carbon material dispersion liquid according to claim 1 or 2, further comprising a conductive carbon material dispersant having a surface active action and a dispersion medium.
The conductive carbon material dispersion according to any one of claims 1 to 3, wherein the conductive carbon material contains one or more selected from graphite, carbon black, and carbon nanotubes.
The conductive carbon material dispersion according to any one of claims 1 to 4, wherein the conductive carbon material contains carbon nanotubes.
The conductive carbon material dispersion according to any one of claims 3 to 5, wherein the dispersion medium contains water.
The conductive carbon material dispersion liquid according to any one of claims 3 to 6, wherein the conductive carbon material dispersant contains a polymer having an oxazoline group in a side chain.
The conductive carbon material dispersion liquid according to claim 7, wherein the polymer having an oxazoline group in the side chain is a polymer of an oxazoline monomer represented by the following formula (1).

(Wherein X represents a polymerizable carbon-carbon double bond-containing group, and R 1 to R 4 each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 5 carbon atoms, or a carbon number of 6 Represents an aryl group having ˜20 or an aralkyl group having 7 to 20 carbon atoms.)
The conductive carbon material dispersion according to claim 8, wherein the chain hydrocarbon group containing a polymerizable carbon-carbon double bond is an alkenyl group having 2 to 8 carbon atoms.
The oxazoline monomer is 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-4-ethyl-2-oxazoline, 2-vinyl-4-propyl-2-oxazoline, 2 -Vinyl-4-butyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2-vinyl-5-ethyl-2-oxazoline, 2-vinyl-5-propyl-2-oxazoline, 2-vinyl -5-butyl-2-oxazoline, 2-isopropenyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-4-ethyl-2-oxazoline, 2-isopropenyl-4 -Propyl-2-oxazoline, 2-isopropenyl-4-butyl-2-oxazoline, 2-isopropenyl-5-methyl Selected from the group consisting of ru-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline, 2-isopropenyl-5-propyl-2-oxazoline and 2-isopropenyl-5-butyl-2-oxazoline The conductive carbon material dispersion according to claim 8, which is one type or two or more types.
11. The conductive carbon material dispersion according to claim 10, wherein the oxazoline monomer is 2-isopropenyl-2-oxazoline.
The conductive carbon material dispersion according to any one of claims 1 to 11, comprising a crosslinking agent.
The conductive carbon material dispersion according to claim 12, wherein the crosslinking agent contains a compound that causes a crosslinking reaction with an oxazoline group.
A compound that undergoes a crosslinking reaction with the oxazoline group exhibits a crosslinking reactivity in the presence of an acid catalyst, a synthetic polymer metal salt and a natural polymer metal salt, and exhibits a crosslinking reactivity when heated. The conductive carbon material dispersion according to claim 13, comprising a compound selected from an ammonium salt of a molecule and an ammonium salt of a natural polymer.
The compound that causes a crosslinking reaction with the oxazoline group includes a compound selected from lithium polyacrylate, sodium polyacrylate, ammonium polyacrylate, lithium carboxymethylcellulose, sodium carboxymethylcellulose, carboxymethylcellulose ammonium, and ammonium alginate. Conductive carbon material dispersion liquid.
The conductive carbon material dispersion liquid according to any one of claims 1 to 15, comprising a polymer to be a matrix.
A conductive tie layer obtained from the conductive carbon material dispersion according to any one of claims 1 to 16.
The conductive binding layer according to claim 17, wherein the thickness is 5 μm or less.
The conductive binder layer according to claim 17, wherein the thickness is 1 μm or less.
The conductive binding layer according to claim 17, wherein the thickness is 0.5 μm or less.
21. A composite current collector for an electrode of an energy storage device, comprising: a current collecting substrate; and the conductive binder layer according to any one of claims 17 to 20 formed on the substrate.
The electrode for energy storage devices provided with the composite electrical power collector for electrodes of the energy storage device of Claim 21.
The electrode for energy storage devices of Claim 22 provided with the composite electrical power collector for electrodes of the energy storage device of Claim 21, and the active material layer formed on the said electroconductive binding layer of this composite current collector. .
An energy storage device comprising the electrode for an energy storage device according to claim 22 or 23.
The energy storage device according to claim 24, which is a lithium ion secondary battery.
A method for producing a conductive carbon material dispersion liquid in which foaming is suppressed, comprising mixing a conductive carbon material, a conductive carbon material dispersant having a surfactant activity, a dispersion medium, and an acetylene surfactant.
A method for defoaming a conductive carbon material dispersion, comprising mixing a conductive carbon material, a conductive carbon material dispersant having a surface-active action, a dispersion medium, and an acetylene surfactant.