JP2002069755A - Filler of gas phase-grown carbon fiber and method for manufacturing filler of gas phase-grown carbon fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filler consisting of a carbon nanofiber which can be filled at such a large bulk-density that the filler can be efficiently transported or the like, and whose bulk-density does not return to the original level at once after removing the pressure, but finally returns to the level substantially same as or close to the original bulk-density, and a method for manufacturing the same. SOLUTION: A filler consisting of gas-phase grown carbon fiber comprising a gas-phase grown carbon fiber having an average diameter of 3-200 nm and capable of being compressed up to a bulk density of 0.1-0.5 g/cm3. A manufacturing method comprising compressing a gas-phase growing carbon fiber having an average diameter of 3-200 nm together with a liquid at 0.2-50 MPa to a bulk density of 0.1-0.5 g/cm3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vapor-grown carbon fiber filler and a method for producing the vapor-grown carbon fiber filler.
More specifically, a vapor-grown carbon fiber filler that is easy to handle and can easily return to its original bulk over time after the pressure is removed, and such a vapor-grown carbon fiber filler It relates to a method that can be easily manufactured.

[0002]

2. Description of the Related Art There is a vapor-grown carbon fiber called a carbon nanofiber because it has a smaller diameter than a vapor-grown carbon fiber having a larger diameter. The aggregate of carbon nanofibers is generally very bulky (low bulk density) immediately after its production.

[0003] Transporting bulky aggregates of carbon nanofibers is inefficient because the amount of carbon nanofibers contained per unit volume is small. To increase transport efficiency, it is necessary to increase the bulk density of the aggregate of carbon nanofibers. However, when the aggregate of carbon nanofibers with a low bulk density is compressed in a container and then the compression force is removed to cover the container, the entire aggregate of compressed carbon nanofibers immediately swells. Would. In other words, the aggregate of carbon nanofibers compressed in the container expands in a short period of time after removing the pressing force and closing the container, so that the container is tightly loaded with the lid. In order to do so, there is a restriction that the lid must be closed very quickly after the pressure is released.

[0004] Further, even if a lid can be quickly loaded into a container filled with carbon nanofibers in a very short time, when the lid is removed from the container next time,
There is a problem that the carbon nanofibers in the container do not return to the original bulk density. For example, if the average fiber diameter is 20n
m, the aggregate of carbon nanofibers having an aspect ratio of 50 or more is pressed in a dry state at about 10 MP, and when the pressure is released, the aggregate of compressed carbon nanofibers expands, but The bulk density is restored only to about 0.03 g / cm ³ . Pressurized from about 50MP the aggregate of the carbon nano fiber, restoring its when the pressure is released, the bulk density although aggregates swell the carbon nanofibers that have been compressed only about 0.05 g / cm ³ Not done. The reason that the aggregate of carbon nanofibers is not restored to its original bulk density when the pressure is released after being once pressed is that part of the carbon nanofibers is broken by the pressurization. Conceivable.

[0005] Further, even when a composite material formed by dispersing broken carbon nanofibers shorter than before pressurization into a synthetic resin is used for conductive applications, the composite material shows good conductivity. There is also a problem that there is no.

[0006] When using carbon nanofibers for specific applications, various surface treatments are sometimes performed after the carbon nanofibers are manufactured. From an industrial point of view, it is desired that carbon nanofibers for specific applications be manufactured with as few steps as possible.

An object of the present invention is to solve the above problems. In other words, an object of the present invention is to fill with a bulk density large enough to allow efficient transportation and storage, and not to return to the original bulk density immediately after removing the pressing force, but ultimately It is an object of the present invention to provide a carbon nanofiber packing capable of returning to a bulk density substantially equal to or close to the original bulk density.

Another object of the present invention is to provide a method for easily producing the carbon nanofiber packing.

[0009]

The present invention for solving the above-mentioned problems contains a vapor-grown carbon fiber having an average diameter of 3 to 200 nm, and contains 0.1 to 0.5 g / cm in the presence of a liquid.
A vapor-grown carbon fiber filler characterized by being compressed to a bulk density of ³ , wherein a vapor-grown carbon fiber having an average diameter of 3 to 200 nm together with a liquid is 0.1 to 0.2 MPa at a pressure of 0.2 to 50 MPa.
The method for producing a vapor-grown carbon fiber filler according to the present invention, which comprises compressing to a bulk density of about 0.5 g / cm ³ .

Further, the present invention for solving the above problems contains a vapor grown carbon fiber having an average diameter of ³ to 50 nm and has a bulk density of 0.1 to 0.5 g / cm ^{3 in} the presence of a liquid. A vapor grown carbon fiber filler characterized by being compressed, wherein a predetermined amount of vapor grown carbon fiber having an average diameter of 3 to 50 nm is compressed together with a liquid at 0.2 to 50 MPa. This is a method for producing a vapor-grown carbon fiber filler.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION A vapor-grown carbon fiber filler according to the present invention is an aggregate of vapor-grown carbon fibers filled in a predetermined closed space, for example, in a container with a predetermined pressure and in the presence of a liquid. When the predetermined pressure is removed, the aggregate does not immediately return to the aggregate of vapor-grown carbon fibers having the original bulk density. It has the property of returning to an aggregate of vapor-grown carbon fibers of high density. Therefore, for example, immediately after removing the pressing force by the pressurizing means applied to the vapor-grown carbon fiber filled in the container, a closing member such as a lid can be easily placed on the opening of the container, When the lid is removed, the filling of the vapor-grown carbon fiber previously filled in the container expands and returns to the aggregate of vapor-grown carbon fibers having the original bulk density. Therefore, the vapor-grown carbon fiber filler according to the present invention is packed in a closed space, for example, a container with a large bulk density, so that the efficiency of transportation and storage is achieved,
In addition, the post-treatment of the vapor-grown carbon fiber, for example, the surface treatment of the vapor-grown carbon fiber can be efficiently performed.

The vapor-grown carbon fiber, which is an element of the aggregate called the vapor-grown carbon fiber filler, has a predetermined average diameter and is compressed and filled into a closed space, for example, a container at a predetermined bulk density. Become.

More specifically, the vapor-grown carbon fiber according to the present invention has an average diameter of 3 to 200 nm, preferably 3 to 50 nm. In other words, the average diameter is 3-50.
An aggregate of vapor-grown carbon fibers in the range of nm is preferable as the vapor-grown carbon fiber filler. Its average diameter is 3 ~
The aggregate of vapor-grown carbon fibers in the range of 50 nm is:
The object of the invention can be achieved particularly well.

However, by allowing the aggregate of vapor-grown carbon fibers having an average diameter of 3 to 50 nm to contain vapor-grown carbon fibers having an even larger diameter, the average diameter of the vapor-grown carbon fibers is increased to 5 nm.
An aggregate of vapor-grown carbon fibers having a thickness of 0 to 200 nm or less can be used as the vapor-grown carbon fiber filler in the present invention.

Here, the average diameter of the vapor grown carbon fiber is:
Scanning microscope (SEM) or transmission microscope (TEM)
It can be calculated by arbitrarily selecting 100 or more fibers from a photograph obtained at a magnification of 30,000 or more and measuring and averaging the outer diameters of the fibers.

The vapor-grown carbon fiber usually has an aspect ratio of not less than 50, preferably not less than 100.
This aspect ratio is an average value. As in the measurement of the average diameter of the vapor-grown carbon fiber, from a photograph obtained at a magnification of 30,000 or more with a scanning microscope or a transmission microscope,
It can be calculated by arbitrarily measuring and averaging the diameter and outer diameter of 100 or more fibers.

When the aspect ratio is at least 50,
In combination with the normal average diameter of the vapor grown carbon fiber, conductivity is well exhibited when the vapor grown carbon fiber is dispersed and mixed with a base material such as resin and ceramic.

The average diameter is from 3 to 200 nm, especially from 3 to 50 nm.
The vapor-grown carbon fiber having a diameter of nm is, for example,
It can be manufactured by the methods described in JP-A-54998, JP-B-62-49363, JP-B-5-36521, JP-A-9-324325, JP-A-9-78360 and the like.

Generally speaking, vapor-grown carbon fibers are produced as follows. That is, high temperature, for example, 90
A catalytic metal is generated by introducing a catalytic metal source, for example, an organic transition metal compound such as ferrocene, and a carbon source, for example, hydrocarbon, carbon dioxide, or carbon monoxide to the reaction region heated to 0 to 1200 ° C. And the carbon generated by the decomposition of the carbon source is grown on the surface of the catalytic metal.
The growth of carbon on the surface of the catalyst metal is performed in one direction, and also occurs in a direction perpendicular to the direction, that is, in a thickness direction. That is, the growth of carbon from the catalytic metal in the axial direction of the vapor grown carbon fiber, that is, the length growth, and the growth in the direction in which the thickness of the vapor grown carbon fiber increases, that is, the thickness growth occur. At this time, a suitable ultrafine vapor-grown carbon fiber according to the present invention can be manufactured by suppressing the thickness growth and selecting a condition in which the length growth is prioritized.

In the present invention, the vapor grown carbon fiber is filled in a closed space, for example, a container. The container is not particularly limited and may be a container provided with a closed space for filling the vapor grown carbon fiber. Further, there is no particular limitation on the use and function of the container. Suitable containers can include containers such as cans used to store or transport vapor grown carbon fibers.

Since the vapor-grown carbon fiber filler filled by the method of the present invention described below contains a liquid,
When the vapor-grown carbon fiber filling containing liquid is kept in a container for a long period of time, the vaporized carbon fiber filling returns to the original aggregate state before compression if the liquid volatilizes. Since the container will return, a pressure-resistant container such as a metal can such as a drum can or a plastic can such as a pail can can be used as the container. Also, as long as the vapor-grown carbon fiber filler contains a liquid, it does not try to return to the original aggregate of vapor-grown carbon fibers before compression as described above, so even if the pressure resistance is not as high as that of a metal can. A container having low pressure resistance may be used as long as the container can be hermetically sealed.

In the case where the vapor growth carbon fiber filler is further graphitized while being filled in a container, the container is required to have heat resistance. Such containers include, for example, graphite containers.

In the present invention, the vapor grown carbon fiber is filled in a closed space, for example, a container. The pressure during filling is 0.2 to 40 MPa (2 to 400 kg / cm
² ), preferably 0.5 to 20 MPa (5 to 200 kg
/ Cm ² ), more preferably 1 to 10 MPa (10 to 1 MPa).
00 kg / cm ² ).

When the pressure is within the above range and the average diameter of the vapor grown carbon fiber is within the above range, the bulk density of the vapor grown carbon fiber is 0.1 to 0.5 g / c.
It falls within the range of m ³ . If the applied pressure is larger than the above range, the aspect ratio of the vapor-grown carbon fiber may be reduced due to breakage or the like, and consequently the conductivity of the composite material may be reduced.

When the pressing force is smaller than the above range,
The bulk density of the vapor-grown carbon fiber does not increase, resulting in a bulky vapor-grown carbon fiber, for example, which lowers the efficiency of transportation and the like.

As a method for applying the pressing force, a method using a press device or the like as described below can be used.

As shown in FIG. 1, the pressing device 6
Is formed in the shape of a cylindrical body having an axis in the longitudinal direction, a piston insertion path 7 provided along the axial direction, and a container connected to the piston insertion path 7 and provided in a direction orthogonal to the axial direction. A mold 3 including an insertion path 4, a movable container 13 inserted into the container insertion path 4 and disposed immediately below the piston insertion path 7, and a movable container 13 inserted into the container insertion path 4, Bottom mold 1 placed directly below insertion path 7
1, and formed to be able to advance and retreat within the piston insertion path 7,
A piston 2 for pressing the vapor-grown carbon fiber inserted into the piston insertion path 7 into the moving container 13.

As shown in FIGS. 1 and 2, the mold 3 is arranged and fixed on a press table 5 supported by an upright press frame 1. The container insertion path 4 has an upper surface which is a surface of the press table 5, a vertical inner wall which is formed by cutting out a lower end surface of the mold 3 and faces in parallel with an axis of the mold 3, and which is orthogonal to the axis. A through hole 8 which is a space provided in the lower end of the mold 3 in a direction orthogonal to the axis of the mold 3 with the ceiling surface formed in the direction in which the mold 3 extends.
The space between the vertical inner walls facing each other in the through hole 8 is designed to have a size in which the bottom mold 11 can move.

The opening of the piston insertion path 7 is opened in the ceiling surface of the through hole 8, thereby connecting the piston insertion path 7 and the container insertion path 4.

The bottom mold 11 is put in and taken out of the container insertion path 4. The bottom mold 11 has, for example, an upper end surface having a diameter sufficient to close the opening. When the bottom die 11 is disposed in the container insertion path 4 so as to close the opening, the upper end surface of the bottom die 11 becomes a bottom surface in the cylindrical space formed by the piston insertion path 7. .

The bottom mold 11 can be advanced or retracted in the container insertion path 4 by a suitable bottom mold advance / retreat drive means (not shown) so that the opening can be closed or opened. I can do it.

The moving container 13 can be inserted into the container insertion path 4. When the moving container 13 is located immediately below the opening, the gas phase charged in the piston insertion path 7 can be inserted. Piston insertion path 7 for growing carbon fiber without hindrance
It has an upper opening and an internal shape sufficient to allow it to be dropped into the moving container 13 from the inside. Therefore, in many cases, the transfer container 13 is a circular bottomed cylinder having an upper opening. Moreover, the movable container 13 which is this bottomed cylindrical body
Is designed not to be smaller than the diameter of the opening, in other words, substantially the same as or slightly larger than the diameter of the opening.

The piston 2 is fitted in the piston insertion path 7 so as to be able to advance and retreat. The piston 2 can be advanced and retracted by a hydraulic cylinder attached to an upper frame of the press frame 1. In the figure, reference numeral 12 denotes a bottom mold 11.
, Which connects the bottom die 11 to the bottom die driving means for moving the bottom die 11 forward and backward.

Using the press apparatus 6 having the above-described configuration, a vapor-grown carbon fiber packing is produced as follows.

As shown in FIG. 3, the piston insertion path 7
The bottom mold 11 is arranged in the container insertion path 4 so as to close the opening of the bottom mold 11. An assembly 14 of vapor-grown carbon fibers is loaded into the piston insertion path 7. During this loading, a liquid described later is added to the aggregate 14 of the vapor-grown carbon fibers. The liquid may be added to the aggregate 14 of the vapor-grown carbon fibers loaded in the piston insertion path 7, but the vapor-grown carbon fibers and the liquid are mixed in advance in an appropriate container. Alternatively, the mixture may be loaded into the piston insertion path 7.
As shown in FIG. 4, the aggregate 2 of vapor-grown carbon fibers loaded in the piston insertion path 7 is compressed by the piston 2. As shown in FIG. 5, pressurization by the piston 2 is stopped. Although the piston 2 is removed from the piston insertion path 7 in FIG. 5, it is not always necessary to remove the piston 2 from the piston insertion path 7, and the vapor growth carbon fiber is not compressed. The piston 2 may be simply separated from the carbon fiber aggregate 14. Next, as shown in FIG.
Is removed, and the movable container 13 is inserted into the container insertion path 4,
The moving container 13 is located immediately below the opening. Even if the bottom mold 11 is moved from just below the opening, the compressed vapor-grown carbon fiber generates a force that tends to spread toward the inner peripheral surface of the piston insertion path 7. The aggregate of grown carbon fibers stays in the piston insertion path 7 even if the bottom mold 11 does not exist below the aggregate. Thereafter, as shown in FIG.
Is lowered to push down the compressed aggregate of vapor-grown carbon fibers into the moving container 13, and the compressed aggregate of vapor-grown carbon fibers is filled in the moving container 13. At this time, the aggregate 14 of the vapor-grown carbon fibers transferred into the moving container 13 is further pressed by the piston 2 so that the aggregate 14 of the vapor-grown carbon fibers And may be filled by compression. As shown in FIG. 8, the moving container 13 filled with the aggregate 14 of the vapor-grown carbon fibers is taken out from the container insertion path 4. By capping the moving container 13 taken out of the container insertion path 4, a vapor-grown carbon fiber filling filled in the moving container 13 is obtained.

In the present invention, a liquid is added to the vapor-grown carbon fiber when the vapor-grown carbon fiber loaded in the container is pressurized by the pressure. This liquid is a liquid at normal temperature and normal pressure, and preferably has a viscosity of 30 N · s / cm.
Liquid that does not exceed ² (300 poise). Specifically, examples of the liquid include an organic solvent, an organic solvent solution, water, and an aqueous solution. Examples of the organic solvent include polar solvents such as alcohols and ketones, benzene,
Aromatic organic solvents such as toluene and xylene, ligroin,
And petroleum solvents such as petroleum ether.

Of the various liquids, lower alcohols such as ethanol and ketones such as acetone well penetrate between the vapor-grown carbon fibers and are easily removed at the time of use of the vapor-grown carbon fibers. Is preferred. Also,
Petroleum such as kerosene and heavy oil, ethylene glycol, and the like are convenient for filling a vapor-grown carbon fiber in a container for a long period of time. That is, even if the aggregate of the vapor-grown carbon fiber filler is stored together with these liquids in a container for a long period of time, these liquids do not volatilize and volatilize. This is because the pressure for returning the aggregate to the original state is not applied to the container. The vapor-grown carbon fibers present together with these liquids are also advantageous in this respect, since it is not necessary to use an oil agent when dispersing them in a base material such as rubber.

Examples of the organic solvent solution include an organic solvent such as a mixed solution of alcohols and water.
When only an organic solvent is used as a liquid, the organic solvent is often flammable, so the mixed filling of the organic solvent and the vapor-grown carbon fiber is dangerous as a flammable substance. , Which reduces its flammability and is safe. In some cases, either water or an organic solvent can be employed as the liquid.

What kind of liquid is selected at the time of pressurization is appropriately determined according to the content and use of the post-treatment applied to the pressurized vapor-grown carbon fiber.

Examples of the method of adding a liquid to the vapor grown carbon fiber include a spraying operation, a liquid spraying operation, and an operation of immersing and stirring the vapor grown carbon fiber in the liquid.

As a post-treatment to be performed on the vapor-grown carbon fiber after the pressure treatment, a graphite container is once filled under pressure with ethanol, and then the ethanol is evaporated off to remove the vapor-grown carbon fiber in the graphite container. 2000-30 with high packing density
There is a graphitization treatment in which heat treatment is performed at 00 ° C.

In the present invention, the amount of the liquid added to 1 part by weight of the vapor grown carbon fiber is usually 0.3
To 3 parts by weight, preferably 0.5 to 2 parts by weight. When the amount of addition is within the above range, the pressure does not return to a bulky state immediately after the pressure is released after the compression. Further, when the container is filled and sealed in the above range, the compressed state is easily maintained. Unnecessarily increasing the amount of liquid is meaningless because the effect is not changed and only the weight is increased.

The temperature at which the vapor-grown carbon fiber is pressurized with the above-mentioned pressurizing force is appropriately selected within a temperature range in which the added liquid does not evaporate, volatilize or volatilize.

The pressurizing time depends on the amount of the vapor grown carbon fiber, but usually from several seconds to about 1 minute is sufficient. When pressurizing the aggregate of vapor-grown carbon fibers, it is preferable to shorten the pressurizing time and repeat the pressurizing operation so that the predetermined packing density is obtained many times, rather than prolonging the pressurizing time.

As described above, the vapor-grown carbon fiber according to the present invention contains a predetermined amount of the vapor-grown carbon fiber having a predetermined average diameter in a container, adds a liquid, and presses a predetermined pressure. Pressing this aggregate of vapor grown carbon fibers in
The bulk density is 0.1 to 0.5 g / cm ³ , preferably 0.1
~ 0.4 g / cm ³ of the filled state.

The use of the vapor grown carbon fiber according to the present invention filled to a specific bulk density as described above is as described above.

[0047]

EXAMPLES Example 1 150 g of carbon nanofibers (extremely fine vapor-grown carbon fibers) having an average diameter of 20 nm and an average aspect ratio of at least 100 when charged into a container having an internal volume of 20 liters were mixed with 150 g of ethanol.
Was added by spraying. Immediately after the addition by spraying, the opening of the container was covered with a lid to form a closed container, and the closed container was shaken to mix the inside vapor-grown carbon fiber and the liquid well to obtain a mixture.

Next, an inner diameter of 136 mm and a height of 200
The mixture obtained by dividing the mixture into 5 equal parts was charged into a cylinder having a diameter of 980.665 × 10 ⁻⁴ Pa (100 kg / c).
cylinder (bottom type) with piston with pressure of m ² )
The mixture inside was compressed and pressed several times. As a result, the compressed mixture was transferred to a graphite container having an inner diameter of 140 mm and a height of 60 mm while applying a slight pressure. This operation was repeated five times to fill the inside of the graphite container with the compressed mixture, and then the opening of the graphite container was closed. The lid has a through hole 8 having a diameter of 3 mm at the center, and is screwed into the opening of the graphite container with a groove screw.

The bulk density of the vapor-grown carbon fibers in the graphite container was 0.19 g / cm ³ .

Sixteen samples prepared under the above conditions were prepared.

All 16 samples were placed in a vacuum dryer at 100 ° C. and left overnight. When the 16 samples were cooled after standing and the lids of the two samples were opened, the carbon nanofibers in each of them were swollen to 5 liters or more and returned to their original bulky state.

The above experimental facts indicate that the filling of the vapor-grown carbon fiber into the container facilitates the filling of the vapor-grown carbon fiber into the container when a liquid is present. This indicates that when the liquid in the container after the filling is no longer present due to volatilization or the like, a restoring force to increase the bulk of the filled and compressed vapor-grown carbon fibers acts.

The remaining 14 samples were placed in argon for 2800
Heat treatment was performed at 30 ° C. for 30 minutes. As a result, the carbon nanofibers in the container were graphitized. Even if the lid of the container was removed, the graphitized carbon nanofibers did not swell and remained inside the container.

The carbon nanofiber before graphitization had an incomplete crystal structure, but the carbon nanofiber after graphitization had an almost complete crystal structure.

(Example 2) Graphitized carbon nanofibers were taken out from each of 14 containers and lightly crushed, and then a water / ethanol (50:50 volume ratio) mixed solution was added in an amount of 80 g per 50 g of the graphitized carbon nanofibers. 147.09975 × 10 ⁻⁴ Pa (15 kg / cm ² ) with a press machine adjusted to the diameter of a 10-liter round can.
Compressed into a disk with a pressing force of Thereafter, the compact was placed in a round can. A total of about 2 kg of graphitized carbon nanofibers were put in a round can, the whole was lightly compressed, and then closed with a lid with styrofoam packing equivalent to about 2 liters interposed therebetween. The round can was filled with 2 kg of graphitized carbon nanofibers and 3.2 kg of a water / ethanol mixture. The bulk density of the carbon nanofiber is about 0.25 g / cm ³ .

After observing the inside of the container after a lapse of one month, there was no abnormality in the external appearance of the round can. Did not.

Comparative Example 1 An attempt was made to fill carbon nanofibers in a graphite container in the same manner as in Example 1 except that ethanol was not used.
0 g (0.05 g / cm ³ ) or more could not be packed.

(Example 3) The procedure of Example 1 was repeated except that 3.2 kg of carbon nanofibers having an average diameter of about 45 nm and an average aspect ratio of at least 100 were used, and 6.8 kg of ethanol were used. When a liter container was filled with carbon nanofibers, the bulk density was about 0.40 g / cm ³ .

[0059]

According to the present invention, without losing conductivity,
In addition, a vapor grown carbon fiber filled with a high bulk density can be provided, and a method for producing a vapor grown carbon fiber filled with a high bulk density can be provided.

Further, according to the present invention, when the pressure is released, the bulk of the vapor-grown carbon fiber restores its bulk with the passage of time and can be easily used for the next use.

According to the present invention, the aggregate of vapor-grown carbon fibers can be compressed and filled to a large bulk density, so that the transportation, transfer, transportation and storage of the aggregate of vapor-grown carbon fibers are efficient. It becomes.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing a front surface of a pressing device as an example for implementing a method according to the present invention.

FIG. 2 is a schematic explanatory view of a press device as an example for carrying out the method according to the present invention when viewed from above.

FIG. 3 is a schematic diagram illustrating a state in which an aggregate of vapor-grown carbon fibers is loaded in a mold in the press apparatus shown in FIG. 1;

FIG. 4 is a schematic diagram illustrating a state in which an aggregate of vapor-grown carbon fibers loaded in a mold in the press apparatus shown in FIG. 1 is pressurized by a piston.

FIG. 5 is a schematic explanatory view showing a state in which a piston is separated from an aggregate of vapor-grown carbon fibers compressed in a mold in the press apparatus shown in FIG. 1;

FIG. 6 is a schematic explanatory view showing a state in which a moving container is disposed immediately below an aggregate of vapor-grown carbon fibers compressed in a mold in the press apparatus shown in FIG. 1; .

FIG. 7 is a schematic diagram illustrating a state in which an aggregate of vapor-grown carbon fibers compressed in a mold in the press apparatus shown in FIG. 1 is pushed into a moving container by a piston.

FIG. 8 is a schematic diagram illustrating a state in which vapor-grown carbon fibers loaded in the moving container in the press device shown in FIG. 1 are taken out of the press device together with the moving container.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Press frame, 2 ... Piston, 3 ... type, 4 ... Container insertion path, 5 ... Press table, 6 ... Press device, 7 ... Piston insertion path, 8 ... Through hole, 11 ... Bottom type, 12 ... Support rod, 13: moving container, 14: aggregate of vapor grown carbon fiber.

Claims (5)

[Claims] 1. The method according to claim 1, which comprises vapor-grown carbon fibers having an average diameter of ³ to 200 nm and contains 0.1 to 0.5 g / cm ^{3 in} the presence of a liquid.
Vapor-grown carbon fiber packing, characterized by being compressed to a bulk density of: 2. A vapor-grown carbon fiber having an average diameter of 3 to 200 nm together with a liquid at 0.1 to 0.5 g at 0.2 to 50 MPa.
/ Cm ^{3, wherein} the bulk density is compressed to a bulk density of / ³ . 3. A gas phase comprising vapor-grown carbon fibers having an average diameter of 3 to 50 nm and compressed to a bulk density of 0.1 to 0.5 g / cm ^{3 in} the presence of a liquid. Growth carbon fiber filling. 4. A gas-grown carbon fiber having an average diameter of 3 to 50 nm together with a liquid at 0.2 to 50 MPa at 0.1 to 0.5 g / g.
A method for producing a vapor-grown carbon fiber filler, comprising compressing to a bulk density of cm ³ . 5. The method according to claim 2, wherein the liquid is water and / or alcohol.