KR20160010399A - Carbon black, electrically conductive resin composition, and electrode mixture - Google Patents

Abstract

The carbon black of the present invention has a BET specific surface area of 350 to 650 m 2 / g, a DBP oil absorption of 270 to 340 cm 3/100 g, and a mode diameter measured by a measurement method of aggregate diameter described in JIS K6217-6 the ratio (D ₉₀ / D _mod) is 1.90 to 2.20 of the D90 diameter (D ₉₀₎ to (D _mod). The conductive resin composition of the present invention contains the carbon black of the present invention and a resin. The electrode material of the present invention contains the carbon black of the present invention, a composite metal oxide, and a binder resin.

Description

TECHNICAL FIELD [0001] The present invention relates to a carbon black, a conductive resin composition, and an electrode composite,

The present invention relates to a carbon black and a conductive resin composition and an electrode composite (electrode composite) containing the carbon black.

Priority is claimed on Japanese Patent Application No. 2013-102327, No. 2013-102328, and Japanese Patent Application No. 2013-102329, filed on May 14, 2013, the contents of which are incorporated herein by reference.

It has been widely practiced to mix carbon black for the purpose of imparting conductivity to a resin material which is an electric insulator. Further, in various fields such as an electrode material, a conductive material for automobiles, a semiconductor package, etc., a conductive resin composition in which carbon black is blended with a thermoplastic resin as an electrical insulator to impart conductivity is widely used. In order to obtain a conductive article having excellent conductivity by the conductive resin composition, the conductivity of the carbon black is important. Examples of the electrode material of the battery include a current collector and an active material layer (active material layer) formed of an electrode material including a composite metal oxide, a conductive material, and a binder resin on the current collector have. As the conductive material, carbon black is widely used. In order to obtain excellent cell performance, it is important that the effect of imparting conductivity of carbon black is excellent.

As the carbon black which can obtain excellent conductivity, for example, those shown below are known.

(i) a partial oxidation reaction of a liquid hydrocarbon (raw material oil) in a furnace in the presence of molecular oxygen and water vapor to produce a synthesis gas and a DBP oil absorption (oil absorption amount) of 290 to 640 cm 3/100 g (For example, Patent Documents 1 to 4).

(Ii) a partial oxidation reaction of a liquid hydrocarbon (raw material oil) in the presence of molecular oxygen and water vapor in a furnace to produce a synthesis gas, a DBP oil absorption of 400 cm 3/100 g or more and a specific surface area (For example, Patent Document 5).

However, the carbon black having a high DBP oil absorption and an excellent conductivity-imparting effect has a poor dispersibility in a dispersion medium such as a solvent and is difficult to uniformly give to a polymer material or the like. Further, when the carbon black is used in the conductive resin composition, the surface smoothness of the produced conductive article tends to be lowered. Further, when this carbon black is used for an electrode material, nonconformity such as an internal short circuit tends to occur.

On the other hand, acetylene black or the like is known as carbon black having a small specific surface area and excellent dispersibility in a dispersion medium. However, when acetylene black or the like is used, it is difficult to obtain a conductive material having a low conductivity-imparting effect and having excellent conductivity. Further, when acetylene black or the like is used for the conductive resin composition, it is difficult to obtain high mechanical strength in the produced conductive article. Further, when acetylene black or the like is used for an electrode material, it is difficult to obtain sufficient battery performance.

Japanese Patent Application Laid-Open No. 60-60912 Japanese Patent Application Laid-Open No. 60-67564 Japanese Patent Laid-Open No. 60-88073 Japanese Patent Application Laid-Open No. 60-152569 Japanese Patent Laid-Open No. 60-197763

The present invention provides a carbon black that is compatible with good dispersibility and conductivity. Further, the present invention provides a conductive resin composition capable of producing a conductive article having high mechanical strength, excellent surface smoothness and conductivity. Further, the present invention provides an electrode material capable of producing an electrode material which is less likely to cause inadequacies such as an internal short circuit and can obtain excellent cell performance.

The carbon black of the present invention satisfies the following conditions (1) to (3).

(1) BET specific surface area is 350 to 650 m2 / g.

(2) the DBP oil absorption is 270 to 340 cm 3/100 g.

(3) non-(D ₉₀ / D _mod) is 1.90 of the diameter D90 (徑) (D ₉₀₎ to a mode diameter (徑) _(mod D) measured by the measuring method described in JIS K6217-6 of aggregate diameter ~ 2.20.

The conductive resin composition of the present invention contains the carbon black and a resin.

The electrode material of the present invention contains the carbon black, the composite metal oxide, and the binder resin.

The carbon black of the present invention can achieve good dispersibility and conductivity. Further, when the conductive resin composition of the present invention is used, a conductive article having high mechanical strength, excellent surface smoothness and conductivity can be produced. Further, by using the electrode material of the present invention, it is possible to manufacture an electrode material which is less likely to cause incompatibility such as short-circuiting and can obtain excellent cell performance.

1 is a graph for explaining a method for obtaining a mode diameter (D _mod ) and a D90 diameter (D ₉₀ ).

[Carbon black]

The carbon black of the present invention satisfies the following conditions (1) to (3). In the carbon black satisfying the following conditions (1) to (3), good dispersibility in a dispersion medium and good conductivity are both satisfied. Further, since the conductive resin composition of the present invention contains the carbon black, it becomes a conductive resin composition capable of producing a conductive article having high mechanical strength, excellent surface smoothness and conductivity. Further, since the electrode material of the present invention contains the carbon black, an electrode material capable of obtaining excellent cell performance can be produced.

(1) BET specific surface area is 350 to 650 m2 / g.

(2) the DBP oil absorption is 270 to 340 cm 3/100 g.

(3) non-(D ₉₀ / D _mod) is 1.90~ the D90 diameter (D ₉₀₎ to a mode diameter (D _mod) as measured by the method of the aggregate diameter (凝集體徑) described in JIS K6217-6 2.20.

The BET specific surface area of the carbon black of the present invention is preferably 350 to 650 m 2 / g, more preferably 350 to 550 m 2 / g, and still more preferably 350 to 500 m 2 / g. When the BET specific surface area of carbon black is not less than the lower limit value, good conductivity tends to be obtained at the time of addition. When this carbon black is added to the conductive resin composition, the conductivity of the conductive resin composition becomes good, and a conductive article having excellent conductivity can be produced. In addition, a conductive article having a high mechanical strength can be produced. Further, when this carbon black is added to the electrode material, excellent battery performance can be obtained. When the BET specific surface area of the carbon black is not more than the upper limit, it is easy to obtain good dispersibility at the time of addition. When the carbon black is added to the conductive resin composition, the dispersibility of the carbon black in the resin becomes good, and a conductive article having excellent surface smoothness can be produced. Further, when this carbon black is added to the electrode material, the dispersibility of the carbon black in the electrode material becomes good, and inconvenience such as short-circuiting in the electrode material is less likely to occur.

The BET specific surface area of carbon black is measured by a method in accordance with ASTM D 3037.

The carbon black of the present invention is a powder composed of a secondary particle composed of a chain member in which a primary particle is grape-wise connected. Since DBP (n-dibutyl phthalate) is absorbed in the void portion of the vesicle-like chain substance, the DBP oil absorption is an important index value of carbon black.

The DBP oil absorption of the carbon black of the present invention is 270 to 340 cm 3/100 g, preferably 270 to 320 cm 3/100 g, and more preferably 285 to 315 cm 3/100 g. If the DBP oil absorption of the carbon black is not less than the lower limit value, good conductivity tends to be obtained at the time of addition. Further, when this carbon black is added to the conductive resin composition, carbon black can efficiently form a network in the resin, and a conductive article having excellent conductivity can be produced. If the DBP oil absorption of the carbon black is below the upper limit, it is easy to obtain carbon black having good dispersibility. Further, when this carbon black is added to the conductive resin composition, the dispersibility in the resin becomes good, and a conductive article having excellent surface smoothness can be produced.

The DBP oil absorption of the carbon black is a value measured at a sample amount of 9 g under the conditions in accordance with ASTM D 2414.

Furthermore, in the carbon black of the present invention, the ratio (D ₉₀ / D _mod) is 1.90 of the D90 diameter (D ₉₀₎ to a mode diameter (D _mod) as measured by the measuring method described in JIS K6217-6 of aggregate diameter To 2.20, preferably 2.00 to 2.20, and more preferably 2.10 to 2.20. If the ratio (D ₉₀ / D _mod) is the lower limit or more, it is possible to obtain a conductive resin composition excellent dispersibility. If less than or equal to the ratio (D ₉₀ / D _mod) is the upper limit, it is possible to obtain a conductive resin composition excellent in conductivity. In addition, by making the amount fall within the above range, a conductive resin composition having high mechanical strength in addition to dispersibility and conductivity can be obtained. Further, the ratio (D ₉₀ / D _mod) that if in the above range, exhibits a stable conductivity.

The D90 diameter (D ₉₀ ) means a particle diameter of a point which is 90% of a cumulative volume distribution curve in which the entire volume of a particle size distribution obtained on a volume basis is taken as 100%, that is, a volume-based cumulative 90% diameter do. Further, the mode diameter (D _mod ) means a particle diameter with the largest appearance ratio in the particle size distribution, that is, a particle diameter at the maximum value of the distribution.

The ratio (D ₉₀ / D _mod ) is an index indicating the spread of the particle size distribution. When the ratio (D ₉₀ / D _mod ) is large, that is, when the particle size distribution becomes broad, good dispersing performance tends to be obtained at the time of addition to a resin or the like. Therefore, in order to achieve both the conductive performance and the dispersion performance, the control of the ratio (D ₉₀ / D _mod ) becomes important.

The D _mod of the carbon black of the present invention is preferably 0.110 to 0.140 占 퐉, and more preferably 0.115 to 0.135 占 퐉. When the D _mod is within the above range, good dispersibility and conductivity tend to be compatible. Further, the ratio (D ₉₀ / D _mod) that if in the above range, exhibits a stable conductivity.

The D ₉₀ of the carbon black of the present invention is preferably 0.230 to 0.300 μm, more preferably 0.250 to 0.290 μm. When D ₉₀ is within the above range, good dispersibility and conductivity tend to be compatible at the same time. In addition, it is easy to obtain a conductive resin composition excellent in conductivity and surface smoothness.

In the present invention, it is preferable that the BET specific surface area is 350 to 550 m 2 / g, the DBP oil absorption amount is 270 to 320 cm 3/100 g, and the ratio (D ₉₀ / D _mod ) of 1.90 to 2.20 is particularly preferable.

The average primary particle size of the carbon black of the present invention is preferably 30 to 55 nm, more preferably 35 to 50 nm. When the average primary particle size of the carbon black is not less than the lower limit value, the dispersibility into the dispersion medium becomes better. When the average primary particle size of the carbon black is not more than the upper limit, good conductivity tends to be obtained at the time of addition. In addition, it is easy to obtain a good conductive resin composition and a good conductive electrode material.

The average primary particle diameter of the carbon black is measured by the method described in the embodiment.

The volatile content of the carbon black of the present invention is preferably 0.8 mass% or less, more preferably 0.5 mass% or less. When the volatile content of carbon black is less than the upper limit value, it is easy to obtain good conductivity performance at the time of addition. In addition, it is easy to obtain a good conductive resin composition and a good conductive electrode material.

The volatile content of the carbon black is measured by the method described in the embodiment.

The ash content of the carbon black of the present invention is preferably 0.05 mass% or less, more preferably 0.03 mass% or less. When the ash content of the carbon black is less than the upper limit, it is easy to obtain stable conductive performance at the time of addition. In addition, the strength of the resin is easily suppressed from lowering. In addition, it is easy to obtain an electrode material that exhibits stable conductive performance.

Also, the ash content of the carbon black is measured by a method in accordance with ASTM D 1506.

The 24M4DBP oil absorption of the carbon black of the present invention (the amount of compressed oil absorbed four times by 165 MPa of carbon black) is preferably 130 to 200 cm 3/100 g, more preferably 140 to 180 cm 3/100 g. If the 24M4DBP oil absorption is below the lower limit, it is easy to obtain a stable conductive performance upon addition. In addition, it is easy to obtain an electrode material having a stable conductive performance. If the 24M4DBP oil absorption is below the upper limit, it is easy to obtain good dispersibility when added. In addition, it is easy to obtain an electrode material having good dispersibility.

The 24M4DBP oil absorption was measured using a sample amount of 20 g under the conditions described in JIS K 6217-4.

In the carbon black of the present invention, the iodine adsorption amount is preferably 420 to 660 mg / g, and the pH of the 1 mass% aqueous solution is preferably 9 to 11. This makes it easy to obtain stable conductivity at the time of addition. In addition, it is easy to obtain a conductive resin composition excellent in conductivity and surface smoothness. In addition, it is easy to obtain an electrode material having a stable conductive performance.

The iodine adsorption amount is measured by the method described in JIS K 6217-1.

The ratio (CTAB / BET) to the CTAB (cetyltrimethylammonium bromide) adsorption specific surface area to the BET specific surface area in the carbon black of the present invention is preferably 0.3 to 0.8, more preferably 0.6 to 0.8. If the ratio (CTAB / BET) is within the above range, stable dispersion performance tends to be obtained. In addition, it is easy to obtain a conductive resin composition excellent in conductivity and surface smoothness.

The CTAB adsorption specific surface area is measured under the conditions described in JIS K 6217-3.

(Production method of carbon black)

As a production method of the carbon black of the present invention, an oil-furnace method can be mentioned.

As a specific example of the oil furnace method, there can be mentioned, for example, a method in which a raw material oil is partially oxidized in the presence of molecular oxygen and water vapor in a furnace to produce a synthesis gas and simultaneously produce carbon black have.

Examples of the carbon furnace include a general electric furnace (GE) furnace and a shell gasification furnace (SG) furnace, and an SG furnace is particularly preferable.

In order to obtain the carbon black satisfying the above conditions (1) to (3), the ratio of the steam (steam ratio) supplied into the furnace per 1 ton of the raw material oil, the molecular oxygen (Acid consumption) of the raw material oil, and the supply amount of the raw material oil supplied into the furnace per unit time, and does not emulsify the raw material oil. That is, it is important to control all manufacturing conditions corresponding to these four items. Particularly, in order to satisfy the condition (3), control of the supply amount of the raw material oil and suppression of emulsification of the raw material oil become particularly important.

The steam ratio is preferably 200 to 450 kg / t, more preferably 250 to 300 kg / t per ton of raw material oil. If the steam ratio is within the above range, it is easy to obtain carbon black satisfying the conditions (1) to (3).

The acid consumption is preferably 500 to 650 Nm 3 per 1 ton of raw material oil, more preferably 550 to 600 Nm 3. If the oxygen ratio is within the above range, it is easy to obtain carbon black satisfying the conditions (1) to (3).

The supply amount of the raw material oil supplied into the furnace per unit time is preferably 1000 to 1800 kg / hr, more preferably 1200 to 1600 kg / hr. If the supply amount of the raw oil supplied in the furnace per unit time is within the above range, it is easy to obtain carbon black satisfying the conditions (1) to (3).

The feed oil is preferably fed without being emulsified. Thereby, it is easy to obtain carbon black satisfying the conditions (1) to (3).

The internal temperature is preferably 1250 to 1350 캜, and more preferably 1300 to 1350 캜.

The internal pressure is preferably 15 to 45 kg / cm2, more preferably 25 to 35 kg / cm2.

The obtained carbon black is preferably dried under a nitrogen gas atmosphere. The drying temperature is preferably 300 to 900 占 폚, more preferably 350 to 700 占 폚, and particularly preferably 400 to 600 占 폚. When the drying temperature is 300 DEG C or higher, volatile matter is reduced and good conductive performance is easily obtained at the time of addition. If the drying temperature is 900 DEG C or less, the degree of graphitization becomes small and it is easy to obtain a good dispersion performance for a resin or a solvent.

As the raw material oil, those generally used for production of carbon black can be used, and liquid hydrocarbons are preferable. For example, petroleum hydrocarbons such as coal-based hydrocarbons such as creosote oil and ethylene bottom oil (EHE oil) . Among them, EHE oil is preferable.

The BMCI value of the raw material oil is preferably 100 to 200, more preferably 120 to 180, and particularly preferably 130 to 160. When the BMCI value is 100 or more, the yield is hardly lowered and is economically preferable. If the BMCI value is 200 or less, stable supply of raw materials is easy.

Further, the BMCI value of the raw material oil is obtained by the following formula.

BMCI value = 48640 / K + 473.7S-456.8

Where K is the average boiling point of the raw oil and S is the specific gravity of the raw oil.

The C / H ratio of the raw material oil is preferably 5 to 20, more preferably 10 to 18. When the C / H ratio is 5 or more, the yield is hardly lowered, and it is preferable from an economical point of view. If the C / H ratio is 20 or less, stable supply of raw material oil is easy.

As the impurity of the raw material oil, the sodium content (minute) is preferably 10 mass ppm or less, more preferably 5 mass ppm or less, and particularly preferably 3 mass ppm or less. When the sodium content is 10 mass ppm or less, it is easy to suppress the metal component such as iron from remaining in the produced carbon.

The iron content of the raw material oil is preferably 10 mass ppm or less, more preferably 8 mass ppm or less, and particularly preferably 4 mass ppm or less. When the iron content is 10 mass ppm or less, it is easy to suppress the adverse effect on the resin composition and the battery characteristics due to the metal remaining in the carbon.

The content of nickel, copper and manganese in the raw material oil is preferably 8 mass ppm or less, more preferably 4 mass ppm or less, and particularly preferably 2 mass ppm or less. When the content of nickel, copper and manganese is 8 mass ppm or less, it is easy to suppress the adverse effect on the resin composition and the battery characteristics due to the metal remaining in the carbon.

The sulfur content of the raw material oil is preferably 1 mass% or less, more preferably 0.5 mass% or less, and particularly preferably 0.01 mass% or less. If the sulfur content is 1% by mass or less, adverse effects on the resin composition and the battery characteristics can be easily suppressed.

The carbon black of the present invention described above satisfies the conditions (1) to (3), so that good dispersibility and conductivity are both satisfied. Further, since the conductive resin composition of the present invention uses carbon black satisfying the conditions (1) to (3), it is possible to produce a conductive article having high mechanical strength, excellent surface smoothness and conductivity. In addition, since the electrode composite of the present invention uses carbon black satisfying the conditions (1) to (3), it is possible to manufacture an electrode material which is less likely to be incompatible, such as an internal short circuit, can do. Further, in the electrode material of the present invention, since the ratio of the composite metal oxide can be increased, the energy density of the battery can be easily improved. Further, the electrode material manufactured using the electrode material of the present invention is excellent in battery performance at least in terms of the amount of carbon black used.

Carbon black having a DBP oil absorption of less than 270 cm 3/100 g and a BET specific surface area of less than 350 m 2 / g (hereinafter referred to as "carbon black (a)") such as acetylene black, , But the effect of imparting conductivity to the resin of the carbon black (a) is low. Carbon black (hereinafter referred to as " carbon black (b) ") having a DBP oil absorption of more than 340 cm 3/100 g and a BET specific surface area of more than 650 m 2 / g is commercially available However, the dispersibility of the carbon black (b) is low. The carbon black of the present invention has a better dispersibility and a better dispersibility than the intermediate performance assumed from the dispersibility and conductivity of the carbon black (a) and the dispersibility and conductivity of the carbon black (b) And has conductivity.

The carbon black of the present invention can be suitably used in fields such as an electrode material, a conductive material for an automobile, a semiconductor package, and the like, which are required to have high dispersion performance in addition to conductivity of a power cable and the like.

[Conductive resin composition]

The conductive resin composition of the present invention contains the carbon black of the present invention and a resin. The conductive resin composition of the present invention may contain components other than carbon black and resin, if necessary.

The proportion of the carbon black in the conductive resin composition (100 mass%) of the present invention is preferably 0.5 to 40 mass%, more preferably 3.0 to 30 mass%. When the proportion of the carbon black is a lower limit value or more, it is easy to obtain a conductive resin composition having excellent conductivity. If the proportion of the carbon black is not more than the upper limit, the strength of the conductive resin composition tends to be lowered.

[Suzy]

The resin is not particularly limited and may be thermoplastic resin or thermosetting resin.

Examples of the thermosetting resin include phenol, melamine, epoxy, and the like.

Examples of the thermoplastic resin include a polyolefin resin, an elastomer resin, a polystyrene resin, a general-purpose resin, an engineering plastic, and a super engineering plastic.

Examples of the polyolefin thermoplastic resin include homopolymers and copolymers of olefins, and copolymers of olefins and other monomers. Specifically, for example, a polyethylene resin such as high density polyethylene, medium density polyethylene or low density polyethylene and linear low density polyethylene produced by a low pressure method, a medium pressure method or a high pressure method; Polypropylene resin; Poly-1,2-butadiene resin; Ethylene-butene copolymer, and the like. Further, copolymers of ethylene, propylene or butylene with acrylate or methacrylate, and those obtained by chlorinating these compounds, respectively, can be mentioned. And mixtures of two or more of the above polymers. Of the polyolefin-based thermoplastic resins, polyethylene resins and polypropylene resins are preferred.

Examples of the elastomeric thermoplastic resin include olefinic elastomers such as ethylene propylene elastomer and ethylene-propylene-diene rubber (EPDM) elastomer; Styrene-based elastomers such as styrene-butadiene-styrene and styrene-isoprene-styrene; Polyamide-based elastomer; Urethane based elastomer; And polyester-based elastomer.

Examples of the polystyrene-based thermoplastic resin include polystyrene, acrylonitrile-butadiene-styrene (ABS) resin, acrylonitrile-styrene (AS) resin and acrylonitrile-acrylic rubber-styrene (AAS) resin.

Examples of other general-purpose resins include polyvinyl chloride (PVC) resins, ethylene-ethyl acrylate (EEA) resins, ethylene-vinyl acetate (EVA) resins, acrylonitrile- Alcohol resins and polylactic acid.

Examples of engineering plastics include polyamide resins such as 6-nylon, 6,6-nylon, 6,10-nylon, 12-nylon and MXD-nylon resins; Polyester resins such as polycarbonate resin, polyethylene terephthalate resin and polybutylene terephthalate resin; Polyacetal resin; And modified polyphenylene ether resins.

Examples of super engineering plastics include polysulfone resins, modified polysulfone resins, polyphenylene sulfone resins, polyketone resins, polyetherimide resins, polyarylate resins, polyphenylene sulfide resins, liquid crystal polymers, polyether sulfone resins, Ether ketone resin, polyimide resin, polyamideimide resin and fluorine resin.

Examples of the polycarbonate resin include an aromatic polycarbonate resin obtained by reacting an aromatic dihydroxy compound with a diester of phosgene or carbonic acid, and an aromatic polycarbonate resin obtained by reacting an aromatic dihydroxy compound with an alicyclic (alicyclic) And an alicyclic polycarbonate resin obtained by using a hydroxy compound.

Examples of the aromatic dihydroxy compound include 2,2-bis (4-hydroxyphenyl) propane, bis (4-hydroxyphenyl) methane, 1,1- Bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane and 4,4'-hydroxybiphenyl.

Examples of the alicyclic dihydroxy compound include isosorbide, spiroglycol, and cyclohexyldiol.

These resins may be blended for the purpose of securing physical properties in accordance with applications. Specifically, a blend of ABS / polycarbonate resin, a blend of polybutylene terephthalate resin / polycarbonate resin, and a blend of polyphenylene ether resin / polyamide resin / styrene-butylene-styrene elastomer .

The proportion of the resin in the conductive resin composition (100 mass%) of the present invention is preferably 60.0 to 99.5 mass%, more preferably 70.0 to 97.0 mass%. When the ratio of the resin is not less than the lower limit value, the strength of the conductive resin composition is prevented from being lowered. If the proportion of the resin is not more than the upper limit, it is easy to obtain a conductive resin composition having excellent conductivity.

[Other Ingredients]

As other components, for example, in order to improve heat resistance, dimensional stability, rigidity, toughness, impact resistance, or mechanical strength, it is possible to use a resin such as a mother glass fiber, silica, talc, calcium carbonate, zinc oxide, barium sulfate, Nickel, nickel oxide, or silicate zirconia. A molding aid or a processing aid may also be added for the purpose of preventing deterioration due to kneading (mixing) or aging of the thermoplastic resin and carbon black and improving moldability. Specific examples include known phenolic antioxidants and lubricants such as phosphorus-based antioxidants, metal soaps, and fatty acid amide derivatives. In addition, known flame retardants, plasticizers and the like may be used depending on the use.

When the conductive resin composition of the present invention contains other components, the proportion of other components in the conductive resin composition (100 mass%) of the present invention is preferably 0.1 to 40.0 mass%, more preferably 1.0 to 30.0 mass% desirable.

The method for preparing (preparing) the conductive resin composition of the present invention is not particularly limited, and a method for mixing and kneading, for example, resin, carbon black, and other components to be used in accordance with necessity, .

The conductive resin composition of the present invention may be, for example, a compound in the form of a pellet by melting and kneading each component. As a method for forming the pelletized compound logo of the conductive resin composition of the present invention, there is no particular limitation, and a method using a known apparatus or equipment can be employed. For example, there may be mentioned a method in which each component is supplied to a kneader, melted and kneaded, extruded from a die, and pelletized using a pelletizer or the like.

Each component of the conductive resin composition of the present invention may be kneaded after homogeneously mixed with a premixer such as a tumbler or a Henschel mixer, for example. In addition, specific components may be supplied to the kneader using a constant amount feeder, a capacity feeder, or the like and kneaded.

Examples of the kneader include a twin-screw extruder with a vent, a twin-screw extruder with a different direction, a twin-screw extruder in the same direction (same direction), a super mixer, a Banbury mixer, a kneader, a tumbler, have.

In the present invention, since the dispersibility of carbon black is good, a conductive resin composition in which carbon black is well dispersed in a resin can be easily prepared even by a known kneading method.

The method for producing a conductive article using the conductive resin composition of the present invention is not particularly limited, and for example, injection molding, extrusion molding, and the like can be appropriately selected depending on the application.

The use of the conductive resin composition of the present invention is not particularly limited, and examples thereof include conductive materials for automobiles, semiconductor packages, and power cables.

[Electrode mixture (electrode mixture)]

The electrode material of the present invention is, for example, an electrode material used for forming an electrode material of a non-aqueous battery, and contains the carbon black of the present invention, a composite metal oxide, and a binder resin.

The proportion of the carbon black in the electrode material (100 mass%) of the present invention is preferably 0.05 to 15 mass%, more preferably 0.5 to 12 mass%, further preferably 1 to 10 mass% By mass to 8% by mass. If the proportion of the carbon black is a lower limit value or more, stable battery performance is easily obtained. If the ratio of the carbon black is less than the upper limit, stable battery performance is easily obtained. Further, by decreasing the proportion of the carbon black, it becomes possible to increase the ratio of the composite metal oxide in the electrode material, so that the improvement of the energy density and the stable battery performance are both easily achieved.

The composite metal oxide is not particularly limited, and a composite metal oxide which is generally used as an electrode active material can be used.

As the composite metal oxide, for example, a lithium transition metal composite oxide represented by Li _x MO ₂ (wherein M represents at least one transition metal and 0.05? _X? 1.10) can be given. As M, at least one species selected from the group consisting of Mn, Co, and Ni is preferable.

As the specific example of the lithium transition metal complex oxide, for _{example, LiCoO 2, LiNiO 2, LiMnO} 2, LiMn 2 O 4, Li 2 MnO 3, LiMn 1/2 Ni 1/2 O 2 , and LiNi _1/3 Co ₁ and the like can be given _{/ 3 Mn 1/3 O 2} .

As the composite metal oxide, for example, an oxide such as LiFePO ₄ , LiFeP ₂ O ₇ , LiMnPO ₄ , LiCoPO ₄ , LiNiPO ₄ , Li ₂ FeSiO ₄ , Li ₂ MnSiO ₄ , Li ₂ NiSiO ₄ and Li ₂ CoSiO ₄ , Bent metal lithium salts may also be used.

The composite metal oxide contained in the electrode material of the present invention may be one kind or two or more kinds.

The proportion of the composite metal oxide in the electrode material (100 mass%) of the present invention is preferably 70 to 99.9 mass%, more preferably 76 to 99 mass%. If the ratio of the composite metal oxide is at least the lower limit value, stable battery performance can be easily obtained. If the ratio of the composite metal oxide is less than the upper limit value, stable battery performance can be easily obtained.

[Binder Resin]

The binder resin is not particularly limited, and a binder resin usually used for an electrode material can be used.

Specific examples of the binder resin include a fluorine resin such as polyvinylidene fluoride and polytetrafluoroethylene, and a polymer having an unsaturated bond such as styrene · butadiene rubber, isoprene rubber and butadiene rubber.

The binder resin contained in the electrode composite of the present invention may be one kind or two or more kinds.

The proportion of the binder resin in the electrode material (100 mass%) of the present invention is preferably 0.05 to 15 mass%, more preferably 0.5 to 12 mass%. If the ratio of the binder resin is at least the lower limit value, stable battery performance can be easily obtained. If the ratio of the binder resin is below the upper limit value, stable battery performance can be easily obtained.

[Other Ingredients]

The electrode material of the present invention may contain other components than the carbon black, the composite metal oxide and the binder resin, if necessary.

Examples of other components include surfactants and the like.

When the electrode material of the present invention contains other components, the proportion of other components in the electrode material (100 mass%) of the present invention is preferably 0.05 to 15 mass%, more preferably 0.5 to 12 mass% .

The method for producing the electrode material using the electrode material of the present invention is not particularly limited and includes, for example, a method in which a slurry obtained by dissolving or dispersing an electrode material in a solvent is applied on a current collector and then the solvent is volatilized , And a method of applying a kneaded kneaded product obtained by kneading each component of the electrode material onto the current collector.

As the current collector, those conventionally used as the current collector of the electrode material can be used, and for example, metal foil made of an alloy mainly containing aluminum and aluminum and the like can be given.

As the solvent, a solvent commonly used in the production of an electrode material can be used. Examples of the solvent include alkyl alcohols such as methyl alcohol, ethyl alcohol and propyl alcohol, alkyl ketones such as acetone and methyl ethyl ketone, (Such as tetrahydrofuran, dioxane, and diglyme), and amides (such as diethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, and dimethylimidazolidinone).

Example

Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited by the following description.

[How to measure]

(DPB oil absorption amount of carbon black)

The DPB oil absorption of carbon black was measured under the conditions in accordance with ASTM D 2414 at a sample amount of 9 g.

(BET specific surface area of carbon black)

The BET specific surface area of carbon black was measured according to ASTM D 3037.

(Ratio of carbon black (D ₉₀ / D _mod ))

The ratio of carbon black (D ₉₀ / D _mod ) was calculated from the results of measurement by the method for measuring aggregate diameters described in JIS K6217-6.

Concretely, carbon black precisely weighed was added to a 20 volume% ethanol aqueous solution to which 3 drops of a surfactant ("NONIDET P-40" manufactured by SIGMA CHEMICAL CO., LTD.) Was added to obtain a carbon black concentration of 0.01 mass% A sample solution was prepared. The sample liquid was subjected to dispersion treatment for 20 minutes by using an ultrasonic cleaner (made by ULTRASONIC STIRRING BATH: LAKOMANUFACTURING CO.) To obtain a carbon black slurry. 10 mL of a spin liquid (pure water) was injected into a centrifugal sedimentation type particle size analyzer ("BI-DCP PARTICLSIZER" manufactured by BROOK HAVEN INSTRUMENTS), and 1 mL of a buffer solution (20% by volume aqueous ethanol solution) was injected. Thereafter, 1 ml of the above-described carbon black slurry was poured in, centrifugally settled at a revolution of 10000 rpm, and the equivalent diameter of the Stokes was calculated with a true specific gravity of 1.78. As shown in Fig. 1, a histogram of the occurrence frequency relative to the Stokes equivalent diameter was made.

The straight line B was drawn parallel to the Y axis from the peak A of the histogram and the intersection with the X axis of the histogram was taken as C. At this time, the diameter of the Stokes in C becomes the mode diameter (D _mod ). In this histogram, the straight line E is drawn parallel to the Y-axis from the point (D) at which the total amount is 90%, and the intersection with the X-axis of the histogram is F. At this time, the diameter of the Stokes in F becomes D90 diameter (D ₉₀ ).

(Average primary particle size of carbon black)

The average primary particle size of the carbon black was determined using a transmission electron microscope. Specifically, a carbon black sample was dispersed in chloroform for 10 minutes by an ultrasonic dispersing machine of 150 kHz and 0.4 kW to prepare a dispersion sample, which was sprayed and fixed on a carbon-reinforced support membrane. This was photographed with a transmission electron microscope, and a particle diameter of 1000 or more carbon blacks was randomly measured from an image enlarged to 50,000 to 200,000 times using an Endter apparatus, and the average value was determined as an average primary particle diameter.

(Volatile matter of carbon black)

First, a magnetic crucible (15 mm in diameter, 30 mm in height, and a capacity of 10 ml) and a lid (lid lid) were preliminarily calcined at 950 賊 20 캜 for 30 minutes and then cooled in a desiccator at room temperature ), And the mass (M _A ) of the magnetic crucible and the lid was precisely weighed to 0.1 mg unit. Subsequently, 2 g of carbon black was filled in the magnetic crucible so as not to exceed 2 mm under the lid, and the lid was weighed so that the mass (MB) was precisely weighed to 0.1 mg unit. Thereafter, heating in an electric furnace of 950 ± 20 ℃ 7 minutes and cooled to room temperature (25 ℃) in the desiccator, once again, the mass (M _C) of carbon by the following equation accurately weighed, and to 0.1㎎ unit The volatile content of black was calculated.

Volatile matter (mass%) = (M _B -M _C ) / (M _B -M _A )

(Ash of carbon black)

The ash content of the carbon black was measured in accordance with ASTM D 1506.

(24M4DBP oil absorption of carbon black)

The measurement was carried out under the conditions described in JIS K 6217-4 using a sample amount of 20 g.

(CTAB adsorption specific surface area of carbon black)

Measurement was carried out under the conditions described in JIS K 6217-3.

(Iodine adsorption amount of carbon black)

Measurement was carried out by the method described in JIS K 6217-1.

(PH measurement method of carbon black)

1 g 占 0.01 g of carbon black was precisely weighed to 0.01 g and collected in a 20 ml beaker. Thereafter, 1 ml of ethyl alcohol and 10 ml of distilled water preliminarily boiled were added to make a dispersion of carbon black. The dispersion was capped with a watch glass and allowed to stand for 60 minutes in a constant temperature room at 25 ° C. It was confirmed that the dispersion liquid was at 25 占 폚 and the readings were read after one minute from the start of the measurement by using a pH meter which was (fair) equilibrated with the pH standard solutions 4, 7 and 9.

[Performance evaluation of carbon black]

(Slurry viscosity of carbon black)

Carbon black and n-methyl-2-pyrrolidone were added in this order under the conditions of a kneading temperature of 25 DEG C and a rotation speed of 300 rpm using a planetary rotating ball mill (manufactured by TOITO KOGYO CO., LTD.) And kneaded for 10 minutes, A slurry having a black concentration of 5% by mass was obtained. Subsequently, the viscosity of the slurry was measured using a rotary viscometer (Physica MCR301, manufactured by Anton Parr) under conditions of 25 DEG C and a shear rate of 1/13 / second for 5 minutes.

(Dispersion performance of carbon black)

Carbon black and n-methyl-2-pyrrolidone were added in this order under the conditions of a kneading temperature of 25 DEG C and a rotation speed of 300 rpm using a planetary rotating ball mill (manufactured by TOITO KOGYO CO., LTD.) And kneaded for 10 minutes, A slurry having a black concentration of 5% by mass was obtained. A polyethylene (PE) coating frame (thickness 0.2 mm) was placed on a high-quality paper (30 mm x 100 mm), and the dispersibility at the time of coating the slurry using a glass rod was measured. And evaluated according to the following criteria.

A: There are no projections that can be visually confirmed.

B: Less than 10 protrusions can be visually confirmed.

C: The number of protrusions that can be visually confirmed is 10 or more and less than 100.

D: More than 100 protrusions can be visually confirmed.

(Surface resistance value of carbon black)

1.2 g of LiFePO ₄ as active material, 0.12 g of carbon black, 0.12 g of polyvinylidene fluoride as a binder, and 0.12 g of polyvinylidene fluoride as a binder were mixed under the conditions of kneading temperature of 25 캜 and rotation speed of 300 rpm using a planetary rotating ball mill and 1.7 g of n-methyl-2-pyrrolidone were placed in this order and kneaded for 10 minutes to obtain a slurry. A PET coating frame (0.2 mm thick) was placed on a high-quality paper (30 mm x 100 mm), and the slurry was coated using a glass rod. Thereafter, the coated paper having the slurry coated thereon was heated at 80 DEG C for 30 minutes to Fotostarra HS-5BH (manufactured by Eiwa Co., Ltd.) to volatilize n-methyl-2-pyrrolidone. After the surface was flattened using a SUS roller, the coated paper was cut to 20 mm x 20 mm, and the cut pieces were flattened by using a SUS roller. The hand press SSP- (Press temperature of 25 占 폚, press pressure of 370 MPa, press time of 1 minute) was carried out using 10A (Shimadzu Corporation). The film was dried under reduced pressure at 60 DEG C for 6 hours using a vacuum oven (Isotemp Vacuum Oven Model 280A, manufactured by Fischer Scientific) to obtain a model positive film composition film (composition film). The surface resistance of the model positive electrode composition film was measured by a resistivity meter (Loresta GP MCP-T610, manufactured by Mitsubishi Chemical Corporation).

[Raw material (oil)]

The characteristics of the raw material used in this Ordinance are shown below.

Type: EHE Yu

Initial temperature: 198 ℃

10% distillation temperature: 220 ° C

50% Effluent temperature: 279 ° C

C / H ratio (ratio): 13.5

Impurities: 3 mass ppm of sodium, 4 mass ppm of iron, 2 mass ppm of nickel, 2 mass ppm of copper, 2 mass ppm of manganese, 10 mass ppm of sulfur

BMCI value: 145

[Ordinance 1]

(Steam feed rate) supplied to the furnace per 1 ton of the raw material oil was 250 kg / t, and the feed rate of the feed oil (feed rate)

Carbon black was obtained by setting the acid consumption (oxygen ratio) to 570 Nm 3 / t, the methane concentration to 0.70 vol%, the internal temperature to 1335 ° C, and the internal pressure to 30 kg / cm 2. The obtained carbon black was dried at 450 캜 in a nitrogen atmosphere. The recovered amount of carbon black per 1 ton of raw oil was 223 kg / t.

[Ordinances 2-4]

Carbon black was obtained in the same manner as in Example 1 except that the oil supply amount, the steam ratio, the acid consumption, the methane concentration, the internal temperature and internal pressure were changed as shown in Table 1, respectively.

[Article 5 of the Ordinance]

The feed rate of the emulsion feed oil in the furnace was 2222 kg / hour (the feed rate as the feed oil of 2000 kg / hr), the steam ratio (steam ratio) supplied into the furnace per 1 ton of the feed oil was 515 kg / Carbon black was obtained with an acid consumption of 635 Nm 3 / t, a methane concentration of 0.83 vol%, an internal temperature of 1305 캜, and an internal pressure of 30 kg / cm 2. The obtained carbon black was dried at 450 캜 in a nitrogen atmosphere. The recovery of carbon black per ton of raw oil was 130 kg / t.

The DBP oil absorption, the BET specific surface area, the D _mod , the D ₉₀ , the ratio (D ₉₀ / D _mod ), the average primary particle size, the recovery amount, the ash, the CTAB adsorption specific surface area, the ratio / BET), 24M4DBP oil absorption, iodine adsorption amount and pH of 1 mass% aqueous solution are shown in Table 1.

[Table 1]

[Examples 1 to 4]

The performance of slurry viscosity, dispersibility and surface resistivity was evaluated for the carbon blacks obtained in the first to fourth embodiments.

[Comparative Example 1]

As the carbon black to be compared, the DBP oil absorption obtained in the Example 5 was 324 cm 3/100 g, the BET specific surface area was 800 m 2 / g, the ratio D ₉₀ / D _mod was 1.80 (D ₉₀ = 0.200 μm, D _mod = 0.111 Mu] m) of carbon black was evaluated.

[Comparative Example 2]

Carbon black having a DBP oil absorption of 193 cm 3/100 g, a BET specific surface area of 55 m 2 / g and a ratio (D ₉₀ / D _mod ) of 3.47 (D ₉₀ = 0.406 μm, D _mod = 0.117 μm) The performance of black was evaluated.

[Comparative Example 3]

Carbon black having a DBP oil absorption of 166 cm 3/100 g, a BET specific surface area of 256 m 2 / g and a ratio (D ₉₀ / D _mod ) of 1.70 (D ₉₀ = 0.292 μm, D _mod = 0.172 μm) The performance of black was evaluated.

[Comparative Example 4]

Comparative carbon black of Example 1, the carbon black as in Comparative Example 3 obtained by blending in a mass ratio of 59/41, DBP oil absorption is 280㎤ / 100g, a BET specific surface area of 576㎡ / g, ratio (D ₉₀ / D _mod) 1.75 (D ₉₀ = 0.238 탆, D _mod = 0.136 탆).

[Comparative Example 5]

A DBP oil absorption of 280 cm 3/100 g, a BET specific surface area of 443 m 2 / g and a ratio (D ₉₀ / D _mod ) of 2.62 (D ₉₀ / D _mod ) obtained by blending the carbon black of Comparative Example 1 and the carbon black of Comparative Example 2 in a mass ratio of 52/48 (D ₉₀ = 0.299 탆, D _mod = 0.114 탆).

Table 2 shows DBP oil absorption, BET specific surface area, ratio (D ₉₀ / D _mod ), and evaluation results of carbon black in Examples and Comparative Examples.

[Table 2]

As shown in Table 2, in the carbon blacks of Examples 1 to 4 satisfying the conditions (1) to (3), the dispersibility was good, the surface resistivity was low, and the conductivity was good.

On the other hand, in the carbon black of Comparative Example 1 which satisfies the condition (2) but does not satisfy the conditions (1) and (3), the conductivity is good, but the slurry viscosity is remarkably high and the dispersibility is poor. The carbon blacks of Comparative Examples 2 and 3 which did not satisfy all of the conditions (1), (2) and (3) had a large surface resistivity and poor conductivity.

In Comparative Examples 4 and 5 in which the two types of carbon black were blended while satisfying the conditions (1) and (2) but did not satisfy the condition (3), the conductivity was inferior to that in Examples, The saints were not obtained.

[Practical example 1a]

10 parts by mass of the carbon black obtained in Example 1 and 90 parts by mass of a polycarbonate resin (trade name: "U.Philon S-3000", manufactured by Mitsubishi Enzianering Plastics Co., Ltd.) were fed to a twin-screw extruder at a cylinder temperature of 260 to 290 ° C Kneaded, extruded, and cooled. Thereafter, a pelletizer was used to obtain a conductive resin composition in the form of a columnar pellet-like compound.

[Examples 2a-4a]

A conductive resin composition was obtained in the same manner as in Example 1a except that the used carbon black was changed as shown in Table 2.

[Comparative Example 1a]

As the carbon black to be compared, the DBP oil absorption obtained in the Example 5 was 324 cm 3/100 g, the BET specific surface area was 800 m 2 / g, the ratio D ₉₀ / D _mod was 1.80 (D ₉₀ = 0.200 μm, D _mod = 0.111 Mu] m) of carbon black and 92 parts by mass of a polycarbonate resin was obtained in the same manner as in Example 1a.

[Comparative Example 2a]

As the carbon black to be compared, a commercially available carbon black having a DBP oil absorption of 193 cm 3/100 g, a BET specific surface area of 55 m 2 / g and a ratio (D ₉₀ / D _mod ) of 3.47 (D ₉₀ = 0.406 μm, D _mod = 0.117 μm) A conductive resin composition was obtained in the same manner as in Example 1a except that 10 parts by mass of carbon black was used.

[Comparative Example 3a]

As the carbon black to be compared, a commercially available carbon black having a DBP oil absorption of 193 cm 3/100 g, a BET specific surface area of 55 m 2 / g and a ratio (D ₉₀ / D _mod ) of 3.47 (D ₉₀ = 0.406 μm, D _mod = 0.117 μm) A conductive resin composition was obtained in the same manner as in Example 1a except that 17 parts by mass of carbon black and 83 parts by mass of a polycarbonate resin were used.

[Comparative Example 4a]

The carbon black to be compared was a commercially available carbon black having a DBP oil absorption of 166 cm 3/100 g, a BET specific surface area of 256 m 2 / g and a ratio (D ₉₀ / D _mod ) of 1.70 (D ₉₀ = 0.292 μm, D _mod = 0.172 μm) A conductive resin composition was obtained in the same manner as in Example 1a except that 17 parts by mass of carbon black and 83 parts by mass of a polycarbonate resin were used.

[Comparative Example 5a]

A DBP oil absorption of 280 cm 3/100 g, a BET specific surface area of 576 m 2 / g and a ratio (D ₉₀ / D _mod ) of 1.75 _{(D 90 = 0.238㎛, D mod} = 0.136㎛) is other than the carbon black with 12 parts by mass, 88 parts by mass of the polycarbonate resin is, similarly to obtain the conductive resin composition as in Example 1a.

[Comparative Example 6a]

A DBP oil absorption of 280 cm 3/100 g, a BET specific surface area of 443 m 2 / g and a ratio (D ₉₀ / D _mod ) of 2.62 (D ₉₀ / D _mod ) obtained by blending the carbon black of Comparative Example 1a and the carbon black of Comparative Example 2a at a mass ratio of 52/48 A conductive resin composition was obtained in the same manner as in Example 1a except that 14 parts by mass of carbon black and 86 parts by mass of a polycarbonate resin were used, which had a melting point (D ₉₀ = 0.299 탆, D _mod = 0.114 탆).

[Volume resistivity]

A plate-shaped evaluation test body having a thickness of 3.2 mm, a length of 76 mm, and a width of 76 mm was produced by injection molding using the pellets of the conductive resin composition obtained in each example, The volume resistivity was measured according to ISO1853 using a digital multimeter Model 2506A. The smaller the value of the volume resistivity, the better the conductivity.

[Surface smoothness]

A film having a thickness of 80 to 100 m, a width of 10 cm, and a length of 10 cm was produced by inflation molding using pellets of the conductive resin composition obtained in each example. The surface of the film was visually observed, and the number of carbon aggregates of 0.2 mm or more was measured, and the surface smoothness was evaluated by the following evaluation criteria. In addition, the smaller the number of the carbon aggregates, the better the dispersibility of the carbon black.

&Quot; B ": the number of carbon aggregates is less than 10;

&Quot; D ": the number of carbon flocculation is 10 or more.

[Mechanical Strength]

A Type 1 test piece (80 mm long × 10 mm wide × 4 mm thick, notch) according to ISO 179 was produced by the injection molding using the pellets of the conductive resin composition obtained in each example. Charpy impact according to ISO179 / 1eA Test was carried out. The higher the Charpy impact strength, the better the mechanical strength.

The DBP oil absorption, BET specific surface area, ratio (D ₉₀ / D _mod ), and evaluation results of the carbon black used in the examples and comparative examples are shown in Table 2a.

[Table 2a]

As shown in Table 2a, in the conductive resin compositions of Examples 1a to 4a using the carbon black satisfying the conditions (1) to (3), high mechanical strength, good surface smoothness and conductivity were obtained.

On the other hand, Comparative Example 1a using the carbon black which satisfies the condition (2) but does not satisfy the conditions (1) and (3) has insufficient dispersibility of the carbon black, and the surface smoothness is inferior. In Comparative Examples 2a to 4a using carbon black not satisfying all of the conditions (1) to (3), at least one of conductivity, surface smoothness and mechanical strength was inferior.

In Comparative Examples 5a and 6a which satisfied the conditions (1) and (2) but did not satisfy the condition (3) and in which two types of carbon black were blended, the dispersibility of the carbon black was not sufficient, The surface smoothness is inferior.

[Example 1b]

(Preparation of electrode material)

100 parts by mass of LiFePO ₄ as a composite metal oxide and 10 parts by mass of carbon black obtained in Example ₁ were mixed under the conditions of a kneading temperature of 25 ° C and a rotation speed of 300 rpm using a planetary rotating ball mill LP-1 (manufactured by Ito KK) , 10 parts by mass of polyvinylidene fluoride as a binder resin, and 170 parts by mass of n-methyl-2-pyrrolidone were added in this order and kneaded for 10 minutes to obtain a slurry of electrode composite. A polyethylene (PE) coating frame (0.2 mm thick) was placed on an aluminum foil (30 mm x 140 mm), and the slurry was coated using a glass rod. Thereafter, the aluminum foil coated with the slurry was heated at 110 DEG C for 1 hour in Fotosutara HS-5BH (manufactured by Ajukawa Co., Ltd.) to volatilize n-methyl-2-pyrrolidone. The surface was flattened using a SUS roller, and then the coated aluminum foil was cut into 20 mm x 20 mm. Thereafter, the cut out portion was flattened using a SUS roller, and pressed (press temperature: 25 DEG C, press pressure: 370 MPa and press time: 1 minute) using a hand press SSP-10A (Shimadzu Corporation). Further, using a vacuum oven (Isotemp Vacuum Oven Model 280A, manufactured by Fischer Scientific), vacuum drying was carried out at 110 DEG C for 5 hours to obtain an electrode material. A plurality of electrode materials were manufactured, and those having a thickness of 25 3 mm measured in a dry box in an argon atmosphere were used for evaluation of battery characteristics.

(Preparation of Evaluation Cell)

The assembly of the evaluation cells was carried out in a dry box in an argon atmosphere. Lithium foil (25 mm x 25 mm) was fixed to a nickel plate (25 mm x 25 mm) by a resin roller. Subsequently, a separator (26 mm x 26 mm) was laminated on the lithium foil, and an electrode material (20 mm x 20 mm) was laminated so that the slurry-coated surface was on the separator side. An aluminum plate (22 mm x 22 mm ). Subsequently, a laminate of a nickel plate, a lithium foil, a separator, an electrode material and an aluminum plate was sandwiched between two pieces of a 26 mm x 55 mm packaging material having the same material as the separator, And inserted into a body having a part. At this time, the resistance in the circuit was measured using a digital tester CDM-03D (manufactured by CUSTOM CORPORATION), and it was confirmed that the resistance value was less than 0.001 OMEGA for short circuit.

After sealing the portion other than the electrolyte injecting portion in the body by using a heat sealer FT-130 (manufactured by Fuji Impulse Co., Ltd.), an electrolytic solution (1M LiPF ₆ -containing ethylene carbonate (EC) / dimethyl carbonate (DMC) = 1/2), and the mixture was allowed to stand at 90 Torr for 5 minutes so that the electrolyte solution was introduced into the electrode material to sufficiently diffuse the electrolyte solution inside the battery. Thereafter, the electrolyte injection portion of the body was sealed with a heat sealer FT-130 to obtain an evaluation cell.

[Examples 2b to 11b]

An evaluation cell was prepared in the same manner as in Example 1b except that carbon black, the composite metal oxide and the binder resin were changed as shown in Table 2b.

[Comparative Example 1b]

As the carbon black to be compared, the DBP oil absorption obtained in the Example 5 was 324 cm 3/100 g, the BET specific surface area was 800 m 2 / g, the ratio D ₉₀ / D _mod was 1.80 (D ₉₀ = 0.200 μm, D _mod = 0.111 Mu] m) of carbon black was used in place of the carbon black of Example 1b.

[Comparative Example 2b]

Carbon black having a DBP oil absorption of 193 cm 3/100 g, a BET specific surface area of 55 m 2 / g and a ratio (D ₉₀ / D _mod ) of 3.47 (D ₉₀ = 0.406 μm, D _mod = 0.117 μm) An evaluation cell was obtained in the same manner as in Example 1b except that black was used.

[Comparative Example 3b]

Carbon black having a DBP oil absorption of 166 cm 3/100 g, a BET specific surface area of 256 m 2 / g and a ratio (D ₉₀ / D _mod ) of 1.70 (D ₉₀ = 0.292 μm, D _mod = 0.172 μm) An evaluation cell was obtained in the same manner as in Example 1b except that black was used.

[Comparative Example 4b]

A DBP oil absorption of 280 cm 3/100 g, a BET specific surface area of 576 m 2 / g and a ratio (D ₉₀ / D _mod ) of 1.75 _{(D 90 = 0.238㎛, D mod} = 0.136㎛) was used as the carbon black is.

[Comparative Example 5b]

A DBP oil absorption of 280 cm 3/100 g, a BET specific surface area of 443 m 2 / g and a ratio (D ₉₀ / D _mod ) of 2.62 (D ₉₀ / D _mod ) obtained by blending the carbon black of Comparative Example 1b and the carbon black of Comparative Example 2b in a mass ratio of 52/48 _{(D 90 = 0.299㎛, D mod} = 0.114㎛) was used as the carbon black is.

[Comparative Examples 6b to 8b]

An evaluation cell was obtained in the same manner as in Example 1b except that carbon black of Comparative Example 2b was used and carbon black, a composite metal oxide and a binder resin were changed as shown in Table 3b.

[Battery characteristics]

The evaluation cell was taken out from the dry box, and the battery electrode portion was fixed with a torque of 15 Nm with an SUS plate. The open circuit voltage was measured using a pocket tester (manufactured by CUSTOM CORPORATION), and the charge / discharge measurement was performed with respect to the evaluation cell showing a voltage of 3.4 V by using the charge / discharge device HJ1001SD8 (manufactured by Hokuto Co., Ltd.) . In the charging / discharging measurement, charging was performed at a constant current of 0.2 C for 5 hours, and then charged at a constant voltage of 4.1 V for 2.5 hours and stopped for 30 minutes. Thereafter, discharging was performed up to 2.0V at a rate of 30C. The ratio of the discharge capacity in the discharge at the rate of 30 C to the theoretical capacity of the evaluation cell was defined as the capacity retention ratio (capacity retention ratio).

The rate 1C indicates a current value capable of discharging the theoretical capacity of the evaluation cell in one hour.

[Battery resistance]

Evaluation cells were prepared in the same manner as in the evaluation of the battery characteristics.

The evaluation cell was taken out from the dry box, and the battery electrode portion was fixed with a torque of 15 Nm with an SUS plate. The open circuit voltage was measured using a pocket tester (manufactured by CUSTOM CORPORATION), and an evaluation cell exhibiting a voltage of 3.4 V was made to have an SOC of 50% by using a charge / discharge device HJ1001SD8 (manufactured by Hokuto Kogyo Co., Ltd.). Thereafter, an AC impedance measurement was carried out using a frequency response analyzer Model 1260 (manufactured by Soradon Corporation), Potensho / Galvanostat Model 1287 (manufactured by Soradoran Corporation). Measurement conditions were amplitude AC potential 2 mV, DC potential 0 CV, and measurement frequency 25 mHz to 100 kHz.

[Dispersion Performance]

In the electrode material obtained in each example, the number of protrusions was observed with naked eyes, and the dispersibility was evaluated according to the following criteria.

A: There are no visible protrusions.

B: Less than 10 protrusions can be visually confirmed.

C: The number of protrusions that can be visually confirmed is 10 or more and less than 100.

D: More than 100 protrusions can be visually confirmed.

[Ratio of composite metal oxide]

The ratio of the composite metal oxide in the electrode composite obtained in each example was calculated by the following formula.

Ratio of composite metal oxide [mass%] = composite metal oxide [parts by mass] / (composite metal oxide [parts by mass] + carbon black [parts by mass] + binder resin [parts by mass]) x 100

The DBP oil absorption, BET specific surface area, ratio (D ₉₀ / D _mod ), and evaluation results of the carbon black used in the examples and comparative examples are shown in Tables 2b and 3b.

[Table 2b]

[Table 3b]

[Table 4b]

[Table 5b]

As shown in Tables 2b and 3b, in Examples 1b to 11b using the carbon black satisfying the conditions (1) to (3), the dispersibility of the carbon black was good and the capacity retention ratio at the rate of 30C was Sufficiently high, low battery resistance, and excellent battery performance were obtained. Further, in Examples 9b and 11b, the battery performance in which the content of carbon black was at least stable was obtained. As a result, it has become clear that by increasing the proportion of the composite metal oxide, it is possible to increase the energy density of the battery while obtaining stable battery performance.

On the other hand, as shown in Tables 4b and 5b, in Comparative Example 1b which satisfies the condition (2) but uses the carbon black which does not satisfy the conditions (1) and (3), the dispersibility of the carbon black is not sufficient , The battery resistance is extremely low, and there is a fear of an internal short circuit. In Comparative Examples 2b and 3b in which carbon black not satisfying all of the conditions (1) to (3) were used, the capacity retention rate at a rate of 30 C was low and battery performance was inferior to those of Examples 1 b to 8 b.

In Comparative Examples 4b and 5b which satisfied the conditions (1) and (2) but did not satisfy the condition (3) and used two kinds of carbon black blended, the dispersibility of the carbon black was not sufficient.

In Comparative Examples 6 to 8 in which carbon black which does not satisfy all of the conditions (1) to (3) were used, in comparison with Examples 9 to 11 in which an electrode composite of the same composition was used except for the carbon black, The capacity retention rate of the battery is low and battery performance is inferior.

Claims (3)

A carbon black characterized by satisfying the following conditions (1) to (3).
(1) BET specific surface area is 350 to 650 m2 / g.
(2) the DBP oil absorption is 270 to 340 cm 3/100 g.
(3) The ratio (D ₉₀ / D _mod) is 1.90 to 2.20 of the D90 diameter (D ₉₀₎ to a mode diameter (D _mod) as measured by the method of measuring diameter of the aggregates according to JIS K6217-6. A conductive resin composition comprising the carbon black according to claim 1 and a resin. An electrode assembly comprising the carbon black according to claim 1, a composite metal oxide, and a binder resin.

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