JP2020055257A - Method for manufacturing group of fine particles and group of fine particles manufactured by the same method - Google Patents

Abstract

To provide a method for manufacturing a group of fine particles that can be effectively used for a wide range of applications, and which has several characteristics such as less manufacturing cost, suitable inclusion of carbon fiber resin, and the fact that the fine particles can be obtained by controlling the ratio of carbon fiber to epoxy resin.SOLUTION: The invention is related to a method for manufacturing a group of fine particles, wherein the carbon fiber-containing epoxy resin body is crushed and the carbon fiber is coated with epoxy resin around the carbon fiber, and the epoxy resin content (CER[mass%]) expressed in the following formula has a specific value, and wherein the CER is reduced (increased) by increasing (decreasing) the rotational speed or circumferential speed of the impeller 14 and/or widening (narrowing) the impeller spacing D of the two impellers 14 when grinding is performed by using an airflow grinder 11. CER[mass%]=100×[mass of epoxy resin in particulate group (g)/[mass of particulate group (g)]SELECTED DRAWING: Figure 2

Description

  The present invention provides a method of manufacturing a fine particle group which is an aggregate of fine particles in which an epoxy resin is coated around a carbon fiber by crushing a carbon fiber-containing epoxy resin body. Mass%]) is controlled by decreasing or increasing the mass.

BACKGROUND ART Carbon fiber reinforced plastics (CFRP) (carbon fiber reinforced plastics) are plastics containing a carbon fiber as a reinforcing material in a matrix resin, and are used in many applications because they have both strength and lightness.
Carbon fiber reinforced plastic (CFRP) is widely used for various applications by dispersing and containing carbon fibers in a matrix resin such as epoxy resin and heating it under pressure or heating it using microwaves. Have been.

  However, scraps produced by the above-mentioned molding; prototypes including failed products; used molded products; etc. are carbon fiber harmful, and the matrix resin is often a thermosetting resin. Recycling is difficult due to difficulties in separating the matrix resin from the matrix resin, and with few exceptions (recycling), landfill disposal is mainly performed.

For example, the following is known as the recycling method.
Patent Document 1 discloses that a matrix resin of carbon fiber reinforced plastic (CFRP) is burned into a flaky carbon fiber mass, which is kneaded with a thermoplastic resin chip while being melted, extruded, cut, and cut into pellets. A technique for performing this is disclosed.
Patent Literature 2 discloses a crushed waste carbon fiber reinforced plastic processed so as to have a large constant direction diameter of 3 mm or more and to have a specific radius of curvature.
Further, Patent Document 3 discloses a method for treating waste plastic in which a fiber-reinforced plastic (FRP) chip and a thermoplastic plastic material are kneaded while being heated and melted, and then cooled and cured to form a dumpling-like solid containing fibers. ing.
Patent Document 4 discloses a first step of producing a detoxifying material by heat-treating a carbon fiber reinforced plastic and burning a matrix resin, and applying a sizing agent to the detoxifying material and kneading the carbon fiber while kneading. There is disclosed a method of recycling a fiber-reinforced plastic, which comprises a second step of pulverizing a recycled material and a third step of pelletizing the recycled material.

The method of separating carbon fiber of carbon fiber reinforced plastic (CFRP) from its matrix resin is extremely difficult by both combustion treatment and chemical treatment, and even if separation is possible, the separated carbon fiber is a harmful substance. As described above, landfill disposal has been mainly performed with the carbon fiber reinforced plastic as it is for reasons such as increased cost of separation.
Further, even if the matrix resin is heated and melted, the matrix resin is often a thermosetting resin such as an epoxy resin. In addition, even if the combustion treatment can render the carbon fiber harmless and the resulting treated product finer, the cost increase due to the burning treatment is unavoidable. there were.
Further, as described in Patent Literature 2, for example, even if it is attempted to crush and recycle it largely, its application range (usage range and application) is extremely limited due to its size.

Patent Document 5 discloses "manufacture of recycled filled fine particles" in which unnecessary carbon fiber reinforced plastic (CFRP) is converted into fine particles having a wide range of application without exposing (detoxifying) carbon fibers by a specific grinding method without exposing carbon fibers. Methods "are described.
However, in order to broaden the application (utilization) range and application of the fine particles, it is necessary to freely control the “existence ratio of the carbon fiber and the epoxy resin” in the fine particles.

  The demand for recycling of carbon fiber reinforced plastics (CFRP) is increasing, but in such known techniques, the production cost including pulverization is high for various re-uses; application of recycled products (fine particles) Insufficient for reasons such as narrow range; remaining harmfulness of carbon fiber; difficulty in adjusting the “content ratio of carbon fiber and epoxy resin” in fine particles or high cost required for adjustment; There was room.

JP-A-7-118440 JP 2000-254919 A JP 2001-030245 A JP 2009-138143 A JP 2018-020500A

The present invention has been made in view of the above background art, and a problem thereof is a type of carbon fiber reinforced plastics (CFRP) (hereinafter sometimes simply referred to as “CFRP”). An object of the present invention is to provide a method for producing a group of fine particles for effectively utilizing a carbon fiber-containing epoxy resin body in a wider field of use.
In addition, the manufacturing cost including pulverization is not required, the apparatus is not large and complicated, the detoxification of carbon fiber is achieved, the carbon fiber is appropriately included by resin, and the proportion of carbon fiber and epoxy resin is controlled. It is an object of the present invention to provide a method for producing a group of fine particles having some of the following characteristics:

  The present inventor has conducted intensive studies to solve the above-mentioned problems, and as a result, using a specific crusher having two or more impellers, and increasing or decreasing the peripheral speed and the rotation speed of the impeller. When the carbon fiber-containing epoxy resin body is pulverized by expanding and / or narrowing the impeller interval between the two impellers, the epoxy resin content (CER [mass%]) of the obtained fine particles is reduced. I found that I can raise and lower it.

  By producing fine particles having different epoxy resin contents (CER [% by mass]) in this manner, the obtained “fine particles having various defined epoxy resin contents (CER [% by mass]) are obtained. Means that the scope of re-use (application fields, types of objects, etc.) has been greatly expanded, and the inventors have found that the above-mentioned problems can be solved, thereby completing the present invention.

That is, the present invention, when pulverizing a carbon fiber-containing epoxy resin body to produce a fine particle group that is an aggregate of fine particles coated with an epoxy resin around the carbon fiber, in the fine particles, the carbon fiber and the carbon fiber A method for producing a fine particle group in which an epoxy resin content (CER [% by mass]) represented by the following formula (1) indicating the proportion of an epoxy resin has a specific value,
When pulverizing the carbon fiber-containing epoxy resin body using a “air current pulverizer that has two or more impellers and pulverizes the particles to be pulverized by colliding them with a swirling air current generated by rotation of the impellers”, The epoxy resin content (CER [% by mass]) is reduced (increased) by increasing (decreasing) the rotation speed or the peripheral speed of the impeller and / or widening (narrowing) the impeller interval between the two impellers. To provide a method for producing a group of fine particles.
CER [% by mass]
= 100 x [mass of epoxy resin in particle group (g) / [mass of particle group (g)]
... (1)

    Further, the present invention relates to a fine particle group obtained by using the above production method, wherein the “epoxy resin content (CER [% by mass])” represented by the above formula (1) is 0.5% by mass. % To 15% by mass or less.

  The present invention also provides a film, a sheet, and a nonwoven fabric, wherein the fine particles produced using the method for producing the fine particles are filled in a resin, laminated or molded, or dispersed in a dispersion medium. , A battery negative electrode, a paint, a building material, furniture, or an electric product housing.

  Further, the present invention is directed to a film or sheet for filling particles, a nonwoven fabric material, a battery negative electrode material, or a dispersed particle for paint, a filling particle for building materials or furniture, or a filling particle for an electric appliance housing. The above-mentioned fine particle group is provided.

According to the present invention, the above-mentioned problems and the above-mentioned problems are solved, and a carbon fiber-containing epoxy resin body, which is a kind of CFRP, which had to be mainly landfilled until now, is reclaimed as a useful material at a sufficiently low cost. it can.
Further, there is no need for a dangerous carbon fiber isolation step, and there is no practical separation or separation of carbon fibers, so there is no problem in safety.
The conventional complete combustion treatment method of CFRP requires enormous energy costs and cannot be reused, and the semi-combustion treatment method as a method of separating CFRP into carbon fiber and a matrix resin (epoxy resin) also requires energy. The cost is high, and the chemical treatment of CFRP is such that the matrix resin (epoxy resin) remains halfway.
For this reason, CFRP recycling has not been put to practical use. However, according to the present invention, CFRP (carbon fiber-containing epoxy resin body) recycling becomes practical.

The production method of the present invention is extremely advantageous in terms of energy cost because it is not burned, and since there is no step of actively separating carbon fibers and matrix resin in the first place, the danger of carbon fibers may become a problem. I can't get it. Also, since the carbon fiber and the matrix resin are not separated, the cost is extremely advantageous.
In addition, the technology of processing particles from "several hundred microns or more to millimeters or more" into regenerated fine particles is not practical because practical applications of the reclaimed products are extremely limited, and landfill disposal is ultimately better. However, if the production method of the present invention is used, the particle size distribution of the fine particle group is preferable (for example, the particle size distribution of a part thereof in the range of 1 μm or more and 120 μm or less). (Distribution)), the particles can be obtained easily and inexpensively while maintaining good physical properties.
Further, according to the present invention, the carbon fibers contained therein do not become too short, and the "characteristics such as an increase in strength unique to carbon fibers" can be utilized even in a reuse destination.

When the fine particle group is produced according to the present invention, the fine particle (group) can be made to have the preferable physical properties described above, and the epoxy resin content (CER [% by mass]) of the fine particle group can be easily reduced at low cost. It can be adjusted safely and accurately without exposure or scattering of carbon fiber.
In particular, in the present invention, it is preferable to reuse the existing carbon fiber-containing epoxy resin body as a raw material.In that case, it is meaningless if the production cost is increased, but in the method for producing the fine particle group of the present invention, it is meaningless. In the pulverization process, a "particle group in which the epoxy resin content (CER [mass%]) is set to an arbitrary value" is obtained, so that an extra sorting step is not required, and the fine particles are produced at a low production cost matched to reuse. Groups can be manufactured.
According to the present invention, fine particles having various epoxy resin contents (CER [% by mass]) can be easily obtained, so that they can be suitably used (reused) as filler particles, dispersed particles, and the like for various applications. It is.

  Since the fine particle group obtained by the production method of the present invention can have an arbitrary epoxy resin content (CER [% by mass]), its use is extremely wide. That is, since the dispersibility in a liquid dispersion medium (such as a solvent for paint) and the dispersibility in a solid dispersion medium (embedding resin, binder resin, etc.) can be improved, the resulting fine particles can be dispersed in a new binder resin. If the film, sheet, structure or the like is (reused as), the applicable range is extremely wide.

FIG. 2 is a schematic diagram illustrating an example of an apparatus used in the present invention. It is the schematic which shows an example of the aspect of two impellers of the airflow crusher used for this invention. 5 is a scanning electron microscope (SEM) photograph showing an example of a fine particle group obtained by the production method of the present invention. (A) Fine particles that have not undergone a classification operation after grinding (b) Large particles that have undergone classification operation after grinding (c) Small particles that have undergone classification operation after grinding 5 is a graph showing an example of a typical particle size distribution of a group of fine particles obtained by the production method of the present invention. (A) (b) Fine particles not particularly classified after pulverization (Examples 1 to 9) (c) (d) (e) Large fine particles subjected to classification after pulverization (Examples 1 to 9) (F) Smaller fine particle group subjected to classification operation after pulverization (Examples 10 to 17)

  Hereinafter, the present invention will be described, but the present invention is not limited to the following specific embodiments, and can be arbitrarily modified within the scope of the technical idea.

The production method of the fine particle group of the present invention is to pulverize the carbon fiber-containing epoxy resin body to produce “a fine particle group that is an aggregate of fine particles in which an epoxy resin is coated around carbon fibers”. "Epoxy resin content (CER [% by mass])" represented by the following formula (1) indicating "the existing ratio of the carbon fiber and the epoxy resin" (hereinafter, "" is simply abbreviated as "CER". May be adjusted to a specific value. In other words, the present invention is a method for producing a fine particle group in which the CER is defined.
CER [% by mass]
= 100 x [mass of epoxy resin in particle group (g) / [mass of particle group (g)]
... (1)

<Carbon fiber-containing epoxy resin body>
Here, the “carbon fiber-containing epoxy resin body” refers to a structure in which carbon fibers are dispersed in “epoxy resin that is a matrix resin”.
It is essential that the matrix resin contains an epoxy resin, but other resins may be mixed therein. Examples of other resins include thermosetting resins such as unsaturated polyester resin, vinyl ester resin, phenol resin, cyanate ester resin, and polyimide resin; polyamide resin (PA), polycarbonate resin (PC), and polyphenylene sulfide resin (PPS). ), Thermoplastic resins such as polyetheretherketone resin (PEEK); and the like.

The “carbon fiber-containing epoxy resin body” used as a raw material in the present invention is not limited, but is preferably carbon fiber reinforced plastics (CFRP), which is no longer required, from the viewpoint of cost reduction.
Here, the term "CFRP that is no longer needed" refers to CFRP that is generally used and sold, which is no longer needed, CFRP that is waste, CFRP that has come out as a prototype (including failed products) by manufacturers, etc. Is mentioned. Specific examples include, but are not limited to, golf club shafts; tennis racket frames; fishing rods; automobile frames and various parts; airplane wings and various parts; Parts; musical instruments, cases of portable goods, etc .;

  The `` carbon fiber-containing epoxy resin body '' as a raw material in the present invention is obtained by heating a prepreg or the like in which carbon fibers are contained and coexisting in an epoxy resin under pressure in an autoclave, or by heating using a microwave or the like. Any of those molded by molding may be used.

<Production method>
The method for producing the fine particle group of the present invention requires a “pulverizing step” of pulverizing the carbon fiber-containing epoxy resin body, but is preferably a “crushing step” of the carbon fiber-containing epoxy resin body, which is obtained in the crushing step. And a "recovery step" for the fine particle group B obtained in the pulverization step. FIG. 1 schematically shows the production method of the present invention and an apparatus used for the production method. Hereinafter, the present invention will be described in the order of the above steps.

<Crushing process>
In the “production method of fine particle group” of the present invention, it is preferable to include a crushing step of crushing the carbon fiber-containing epoxy resin body before the crushing step described later. In other words, before the carbon fiber-containing epoxy resin body is introduced into the airflow pulverizer 11, the carbon fiber-containing epoxy resin body is crushed to a range allowable as a size to be charged into the airflow pulverizer 11, and “the crushed product A of the carbon fiber-containing epoxy resin body” is obtained. It is preferable to keep
The apparatus used for the crushing is not particularly limited, and examples thereof include a cutter mill, a crusher mill, a hammer mill, and an axial flow mill.

The crushing size of the crushed material A depends on the airflow crusher 11 to be used, but as the maximum crossing length of the crushing object, a size in the range of 0.2 cm to 5 cm is preferable, and a size in the range of 0.5 cm to 3 cm is preferable. Particularly preferred.
If the size is too large, there are cases where the pulverizer 11 cannot satisfactorily pulverize; the case where the fine particles B cannot be obtained by adjusting the CER; On the other hand, if the size is too small, there is no need to reduce the size to that extent, which is disadvantageous in terms of cost; if the merits of the airflow crusher 11 cannot be obtained, that is, if the carbon fiber and the epoxy resin are separated, The fine particle group B cannot be obtained by adjusting the CER (when the CER cannot be crushed while controlling the CER);

<Pulverization process>
The “method of producing a group of fine particles” of the present invention includes “an airflow crusher 11 that has two or more impellers 14 and crushes and crushes particles to be crushed by swirling airflow generated by rotation R of the impeller 14”. When the carbon fiber-containing epoxy resin body is crushed by using, the rotation speed or the peripheral speed of the impeller 14 and / or the impeller interval D between the two impellers 14 is adjusted (adjusted), whereby the above-mentioned “ Epoxy resin content (CER [% by mass]) "is arbitrarily adjusted (adjusted).
Here, the "air flow crusher" refers to a device that generates an air flow by the rotation R of the impeller (rotary wing) 12 and crushes an object put in the air flow in a dry manner to produce fine particles.
FIG. 1 shows a schematic view of an example of an apparatus used in the manufacturing method of the present invention.

In the above-mentioned pulverization step, the carbon fiber-containing epoxy resin body is pulverized using the airflow pulverizer 11, and the upper limit is preferably not more than 200 μm, more preferably not more than 100 μm, particularly preferably not more than 100 μm. A fine particle group B having a diameter distribution of 70 μm or less is obtained.
The lower limit of the particle size distribution can be set to preferably 1 μm or more, more preferably 2 μm or more, and particularly preferably 3 μm or more, as the particle size distribution after collecting the ultrafine particles (group) by the dust collector 42 in the collecting step described later. And crush.
Within this range, the particles are easily pulverized by the airflow pulverizer 11, the carbon fibers are not exposed or liberated (separated), and the “defined (desired) CER fine particle group B” is easily obtained (the CER can be controlled). ), The finally obtained fine particle group B has the above-mentioned effect.

  When pulverized by the airflow pulverizer 11, it is easy to pulverize in the range of the particle size distribution described above; the carbon fibers are not exposed on the surface of the pulverized fine particles and / or the carbon fibers are not released from the fine particles (group); The temperature rise of the target object is suppressed by the pulverization by the collision; mainly, the pulverization is performed by the collision of the particles, so that the above-mentioned various effects can be easily exerted (for example, a form having suitability as filled fine particles and dispersed fine particles). It is crushed; it is crushed mainly by collision between particles, not by shearing with a metal blade, so that the obtained fine particles (group) have very little metal contamination.

  In particular, as a further application, when the obtained fine particle group B is dispersed in a binder resin to produce a film, sheet, structure, or the like, the fine particles (group) are excellent in dispersibility and aggregation is suppressed. With respect to films, sheets, structures, etc., surface color unevenness prevention (color uniformity); excellent in conductivity, antistatic properties, jet-blackness, anticorrosion properties, extrusion suitability, etc .; Bleeding of carbon fibers to the surface is suppressed, and it is difficult to contaminate articles, limbs, clothes, etc., which are in contact with the surface, with black; it is safe without scattering and separation of carbon fibers. can get.

  For example, when a crusher mill, a pin mill, a cutter mill, a hammer mill, an axial flow mill, or the like is used, it is difficult to sufficiently reduce the average particle diameter while suppressing costs (for example, it is difficult to pulverize until the particle diameter becomes 120 μm or less to 90 μm or less). Difficult), the particles obtained by pulverizing with these pulverizers were obtained because the average particle size was too large or the particle size distribution was too wide and the maximum particle size was too large (fine). The use of the particles is limited, that is, there is almost no use of the structure obtained by dispersing the obtained (fine) particles in the binder resin, or the range of use of the structure is limited.

  For example, as described above, a crusher such as a rotary collision type that collides with a rotating body, a roll type, a medium type, a millstone type, a cutter type, etc., applies mechanical stress such as impact, compression, friction, and shear to a crushed object. Since it is added excessively, it is difficult to sufficiently reduce the (average) particle size, and the obtained “fine particle group B” cannot achieve the “effect when using the airflow pulverizer” of the present invention. There are cases.

  On the other hand, a jet mill or the like, which crushes an object by colliding the object with a collision plate, can reduce the average particle size to a sufficiently small value, but the needle-like carbon fibers are exposed or separated, and the crushing operator and the obtained fine particle group are separated. It is extremely dangerous for the user of B. Further, there is a case where the pulverization processing efficiency (speed) is too low to increase the cost.

The airflow pulverizer 11 is used for pulverizing foodstuffs / feedstuffs containing components such as starch and protein that are easily degraded by heat, components that easily emit fragrance by heat, and components that easily adhere to the inside of the pulverizer by heat. Are particularly preferably used.
In the pulverization step of the present invention, the airflow pulverizer used for pulverizing foodstuffs / feeds, etc., obtains the fine particle group B, the particle size distribution, the average particle size, the pulverization efficiency (speed), and the pulverization target. It is particularly preferable in terms of suppression of temperature rise.

  Further, as the airflow crusher 11, a commercially available device can be suitably used. Commercial products include, for example, a cyclone mill manufactured by Shizuoka Plant Co., Ltd., a cyclone mill manufactured by Shizuoka Machinery Co., Ltd., a super powder mill manufactured by Nishimura Machinery Co., Ltd., a tornado mill manufactured by Sanjo Industry Co., Ltd., and Furukawa Soki Dream Mill manufactured by Systems Co., Ltd., and the like.

The structure of the airflow pulverizer 11 is not particularly limited, but has two or more impellers 14, and mainly generates particles to be pulverized by a swirling airflow generated when the impeller 14 is rotated by the motor 13 or the like. It is preferable that the particles be made to collide to form fine particles from the viewpoint of easily obtaining the above-mentioned effects by using the airflow crusher 11 (FIGS. 1 and 2).
In particular, specifically, the temperature rise of the object to be crushed is suppressed; separation of “carbon fiber” and “epoxy resin as a matrix resin” in the carbon fiber-containing epoxy resin body to be crushed is suppressed ( It is preferable from the viewpoints that release of carbon fibers is suppressed); exposure of carbon fibers to the surface of the fine particles is suppressed; and metal contamination caused by materials used for the impeller 14, the blade, and the like is extremely small.
By using the airflow pulverizer 11, the carbon fibers covered with the epoxy resin can be obtained by suppressing the separation of the carbon fibers and the epoxy resin, or by suppressing the carbon fibers from being exposed to the surface of the fine particles. The effects described above are particularly exhibited, and the quality is also stabilized. In addition, since the release of carbon fibers is suppressed, it is safe for workers, users, and the like.

The “production method of fine particle group” of the present invention is to increase (decrease) the rotation speed or the peripheral speed of the impeller 14 when pulverizing the carbon fiber-containing epoxy resin body using the airflow pulverizer 11, and And / or increasing (decreasing) the impeller distance D between the two impellers 14 to reduce (increase) the epoxy resin content (CER [mass%]) represented by the following formula (1). Features.
However, the parentheses of “raise (lower)”, “widen (narrow)” and “reduce (raise)” are in the same order in the three descriptions.
CER [% by mass]
= 100 x [mass of epoxy resin in particle group (g) / [mass of particle group (g)]
... (1)

  The present invention has been made by newly finding the above fact. In other words, the existing carbon fiber-containing epoxy resin body can be pulverized while arbitrarily adjusting the "CER suitable for the use of the obtained fine particles". It has been found that "fine particles" can be obtained.

When the fine particles (group) are produced by pulverization as described above, the CER of the obtained fine particle group B is “Ceramic resin containing epoxy resin contained in carbon fiber-containing epoxy resin used as raw material”. It becomes smaller (can be made smaller) than the content ratio to “the whole body”.
That is, according to the present invention, the content of epoxy resin (CER [mass%]) of the fine particle group B to be produced is such that the epoxy resin contained in the carbon fiber-containing epoxy resin body is contained in the entire carbon fiber-containing epoxy resin body. This is also a method for producing the above-mentioned fine particle group smaller than the ratio [mass%].

FIG. 2 shows a schematic diagram of an example of the airflow crusher 11 having two impellers 14.
The number of the impellers 14 provided in the airflow crusher 11 is preferably two or more from the viewpoint of the crushing efficiency, and two impellers 14 among them can be rotated in the same direction or in the opposite direction. You may.

The rotation speed of the impeller 14 also depends on the diameter of the impeller 14, but (for example, when using an impeller having a diameter of 150 mm to 600 mm) is preferably 3000 rpm or more and 14000 rpm or less, more preferably 4000 rpm or more and 12000 rpm or less, and more preferably 5000 rpm or more. Particularly preferred is 10,000 rpm or less (FIG. 2). Within the above range, a good swirling airflow can be easily generated in the apparatus, and efficient pulverization can be performed. In particular, CER can be easily adjusted to any suitable value (range).
The peripheral speed of the impeller 14 hardly depends on the diameter of the impeller 14, and is preferably from 60 m / s to 300 m / s, more preferably from 80 m / s to 260 m / s, and particularly preferably from 100 m / s to 220 m / s. (FIG. 2). Within the above range, a good swirling airflow can be easily generated in the apparatus, and efficient pulverization can be performed. In particular, CER can be easily adjusted to any suitable value (range).

  The distance D between the two impellers 14 is preferably adjusted within the range of 15 mm to 60 mm for pulverization, more preferably 18 mm to 50 mm, and particularly preferably 20 mm to 40 mm (FIG. 2). Within the above range, a good swirling airflow can be easily generated in the apparatus, and efficient pulverization can be performed. In particular, CER can be easily adjusted to any suitable value (range).

If the rotation speed and the peripheral speed of the impeller 14 are too slow and / or the impeller interval D between the two impellers 14 is too narrow, the particles cannot be sufficiently crushed, especially the particle size cannot be made sufficiently small (for example, 70 μm or less). In some cases, the CER may become too large.
On the other hand, when the rotation speed and the peripheral speed of the impeller 14 are too high, and / or the impeller interval D between the two impellers 14 is too wide, the production (crushing) efficiency is too low, and the operation cost is too high. , Time and cost may be wasted, and the CER may be too small.

  The operation method of the airflow crusher 11 may be a continuous charging (continuous feed) method or a batch (batch) method. In the case of the continuous charging method, the charging speed (feed speed) of the carbon fiber-containing epoxy resin body to be crushed is set. ) Is preferably 0.5 [(kg / min) / L] or more and 3 [(kg / min) / L] or less, preferably 1 [(kg / min) / L] per volume (L) of the airflow pulverizer. It is more preferably at least 2.5 [(kg / min) / L] and particularly preferably at least 1.5 [(kg / min) / L] and 2 [(kg / min) / L].

  When the charging speed is too high, there are cases where the pulverization cannot be performed sufficiently, particularly when the particle size cannot be sufficiently reduced (for example, 70 μm or less). In addition, when the charging speed is too slow, the production (crushing) efficiency is too low, the operation cost is too high, and the time and cost are wasted.

  Although not particularly limited, the airflow pulverizer 11 has a classification function inside, and the classified coarse powder side is pulverized again inside the airflow pulverizer 11, and the classified fine powder side is used as a fine particle group B. It is particularly preferable that the particles are transferred to the collection device 20 through the transfer pipe 22 from the viewpoint of removing coarse powder, giving a suitable particle size distribution to the finally obtained fine particle group B, and the like.

The upper limit of the temperature of the object to be pulverized during the pulverization is preferably maintained at 70 ° C. or lower, more preferably 60 ° C. or lower, still more preferably 50 ° C. or lower, and particularly preferably 40 ° C. or lower. If the temperature is too high, the effect of using the airflow crusher 11 may not be obtained.
The lower limit of the temperature is not particularly limited, and is preferably room temperature at the time of pulverization. That is, 0 ° C. or higher is preferable, and 10 ° C. or higher is particularly preferable.

As shown in FIG. 3, the fine particle group B obtained as described above is rounded by the impact at the time of pulverization using the airflow pulverizer 11, rather than being fibrous or acicular. Note that the shape of the fine particle group B that has undergone a collecting step described later is the same, as shown in FIG.
At the time of pulverization by the airflow pulverizer 11, the epoxy resin contained in the raw material extends so as to coat the surface of the carbon fiber, and embeds and covers the carbon fiber.

<Recovery process>
The method for producing a group of fine particles of the present invention includes a step of collecting fine particles. The recovery device 20 used in the recovery step is not particularly limited, and may be, for example, simply recovered in a container as it is, may be recovered using a filter, or may be recovered using a cyclone device 21. By using (at the end of) each recovery method, using a bag filter or the like, the average particle diameter is smaller than the fine particle group B, or even if it is large, the CER is extremely large (for example, the CER is 100 [% by mass]). May be collected. The collection of the ultrafine particles (group) is also a kind of the collecting method (step) (included in the collecting method).
Among the recovery steps, a preferred embodiment is that the carbon fiber-containing epoxy resin body is pulverized using the airflow pulverizer 11 and then the fine particle group B is recovered using the cyclone device 21.

FIG. 1 shows an example of an embodiment in which the cyclone device 21 is used in the recovery step. In FIG. 1, the cyclone device 21 includes a transfer pipe 22, a cyclone part 23, a damper 24, and a final recovery container 25 in this order from the side of the above-described airflow crusher 11.
The cyclone device 21 is suctioned (S), and the fine particle group obtained in the pulverizing step is transferred to the cyclone site 23, and the cyclone device 21 is operated (by suction S) to remove the fine particle group B from the pulverization process. Collected in the final collection container 25.

In the cyclone portion 23, the heavy (large) particles are pressed against the outer periphery (near the periphery) of the cyclone by centrifugal force, and fall while rotating (circulating) downward along the outer periphery.
On the other hand, the light (small) particles, after falling, move upward near the center axis of the cyclone portion 23. The fine particles that have moved to the upper part fall again on the cyclone part 23, but the ultrafine particles pass through the cyclone part 23 and are collected by the ultrafine particle collection device 41.
Here, the “ultra-fine particle group C” collected by the ultra-fine particle collecting device 41 (preferably) mainly contains fine particles having a particle diameter of 1 μm or less, and substantially does not contain carbon fibers, or Some include very small amounts of carbon fibers. In this case, even if the particle size is not smaller than that of the fine particle group B, it is included in the ultra fine particle group C as a definition.

The damper 24 located below the cyclone portion 23 is normally opened, and the fine particle group B that has fallen around the cyclone portion 23 during operation of the cyclone device 21 is collected in the final collection container 25.
The supply (feed) speed of the fine particle group to the cyclone device 21 is substantially the same as the feed speed (feed speed) of the raw material in the above-described pulverization step when the process is performed continuously.

The ultrafine particle collecting device 41 preferably has a bag filter, and preferably collects the ultrafine particle group C having a particle size of 1 μm or less.
In FIG. 1, among the fine particles that have moved to the upper part of the cyclone part 23, the ultrafine particles that have penetrated upward without returning to the cyclone part 23 are collected by an ultrafine particle collection device 41 including a dust collector 42.
The obtained ultrafine particles may be discarded, or relatively rich in epoxy resin (because of a large CER), and may be reused by utilizing it.
According to the present invention, using the dust collector 42, the average particle size is smaller than the fine particles contained in the fine particle group B, or the epoxy resin content (CER [% by mass]) is the epoxy resin content of the fine particle group B. (CER [mass%]) It is also the above-mentioned "method of producing fine particle group" for collecting ultra fine particles (group) of not less than (CER [% by mass]).

The particle size distribution of the fine particles obtained in the collection step is, as for the upper limit, the same as the “fine particle group to be subjected to the cyclone device 21 after the pulverization”, preferably 200 μm or less, more preferably 100 μm or less, particularly preferably 70 μm or less. It is.
The lower limit of the particle size distribution is preferably 1 μm or more, more preferably 2 μm or more, and particularly preferably 3 μm or more as the particle size distribution after the ultrafine particles (group) are collected by the dust collector 42 or the like.
Further, the present invention is also preferably the method for producing a fine particle group described above, wherein the average particle diameter of the fine particle group B is 2 μm or more and 70 μm or less, and the average particle diameter of the fine particle group B is 3 μm or more and 50 μm or less. This is also a method for producing the above-described fine particle group.
FIG. 4 shows an example of the particle size distribution of the fine particle group B produced by the production method of the present invention.

  According to the present invention, the pulverization / classification / recovery can be performed so that the particle size distribution and the average particle size described above are obtained by using the airflow pulverizer 11 and particularly using the cyclone device 21 in the recovery step. The fine particle group B having the above-mentioned particle size distribution and average particle size that is classified is suitable because it is particularly widely used as filler particles and dispersed particles.

In the present invention, “particle size distribution” refers to a range (μm) in which 80% by mass (volume%) or more of the fine particles fall.
The particle size distribution and the average particle size in the present invention are defined as those measured by a wet method using a laser diffraction / scattering type particle size distribution measuring device Microtrack manufactured by Nikkiso Co., Ltd. and measured by the measuring device (method). You.
The vertical axis of the particle size distribution in the present invention is mass (volume), and the “average particle size” refers to the volume (mass) average particle size measured by the above apparatus.

<Mixing process>
Although not limited, that is, the fine particle group B obtained by the above-described manufacturing method may be used as it is, or may be transferred or sold as a product. When not obtained, it is also preferable to mix the separately produced fine particle groups B to obtain an optimum CER and particle size distribution so as to obtain an optimum CER and particle size distribution.
In particular, the CER has an optimum point depending on the subsequent use, and often needs to be adjusted at the stage of manufacturing the fine particle group B.

The present invention provides an epoxy resin content (CER [CER [CER [%]) by mixing two or more types of fine particle groups B having different epoxy resin contents (CER [% by mass]) obtained by the above-mentioned "method of producing fine particle group". Mass%]) is also adjusted.
Here, the ultrafine particle group C can also be mixed with the fine particle group B by utilizing the fact that the CER is usually large.
The mixing ratio of the two or more kinds of fine particle groups B can be calculated by calculating the CER of each fine particle group B, and the particle size distribution is usually calculated because it has additive properties.

<Particle group>
The present invention relates to a fine particle group obtained by using the above-mentioned “method of producing a fine particle group”, wherein the “epoxy resin content (CER [% by mass])” represented by the above formula (1) is 0. It is also a group of fine particles characterized by being in a range of from 0.5% by mass to 15% by mass.
The CER of the fine particle group of the present invention is more preferably 1% by mass to 14% by mass, further preferably 2% by mass to 13% by mass, and particularly preferably 3% by mass to 12% by mass. is there.

Although it depends on the content of the epoxy resin in the carbon fiber-containing epoxy resin body as the raw material, as long as it is within the above range, various methods can be used while suitably controlling the CER using the “method for producing fine particle groups” of the present invention. Fine particle group B can be produced.
Further, when the CER is in the above range, the use as the fine particle group B is wide; the filling property into the binder resin and the dispersibility in the dispersion medium are good in the application; the carbon fibers are hardly exposed and isolated from the fine particles; effective. As the fine particle group B of the present invention, “these fine particle groups having different CERs” can be properly used depending on the application.

As described above, the fine particle group B of the present invention can have a particle size distribution of 1 μm or more and 200 μm or less, and 2 μm or more and 100 μm or less in the pulverization step by the airflow pulverizer 11 and the recovery step (by the cyclone device 21 or the like), 3 μm or more and 70 μm or less.
After that, the fine particle groups B within the above range are subjected to a classification operation or the like to obtain a plurality of fine particle groups B having different particle size distributions (for example, “a fine particle group B having a particle size distribution of 1 μm or more and 40 μm or less, A large particle group B having a diameter distribution of 3 μm or more and 120 μm or less ”) can be obtained, and these can be used properly depending on the application.

Apart from the classification in the airflow pulverizer 11, a scanning electron microscope (SEM) photograph of the fine particles that have not been subjected to the classification operation after the pulverization is shown in FIG. FIG. 3 (b) shows a photograph, and FIG. 3 (c) shows an SEM photograph of a group of small particles subjected to the classification operation. The fine particles shown in FIG. 3 have a rounded surface.
4 (a) and 4 (b) show the particle size distribution of the fine particles that have not been subjected to the classification operation after the pulverization, and FIGS. 4 (c), (d), and (e) show the particle size distribution of the large fine particles that have been subjected to the classification operation. FIG. 4 (f) shows the particle size distribution of the group of small particles subjected to the classification operation.

As described above, when the carbon fiber-containing epoxy resin body is pulverized by the airflow pulverizer 11, the objects to be pulverized collide with each other to produce fine particles having a rounded surface. In addition, there are few carbon fibers exposed on the surface, and there is no mixing of metal elements derived from the pulverizer. Also, the temperature rise during pulverization is small. From the above, it is considered that the obtained fine particles (group) are in a special mode.
However, it is almost impossible to directly specify the shape of such fine particles by parameters, etc., and to directly specify the form and amount of the carbon fiber exposed on the surface, or to quantify the trace amount of metal contained. Is impossible or almost impractical.

  In addition, the CER of the obtained fine particle group B usually changes from the epoxy resin content of the carbon fiber-containing epoxy resin used as a raw material (the CER is shifted to a lower one), and differs for each fine particle. Therefore, it is impossible or almost impractical to directly specify the component composition of the microparticle (s).

<Application>
The present invention is for a filler particle for a film or sheet, a nonwoven fabric material, a battery negative electrode material, or a dispersed particle for a paint, a filler particle for a building material or furniture, or a filler particle for a housing of an electric product. This is also the above-mentioned fine particle group B.
Further, the present invention is characterized in that the fine particle group B manufactured by using the above-mentioned “method of manufacturing fine particle group” is filled in a resin, laminated or molded, or dispersed in a dispersion medium, a film, It is also a method for producing a sheet, a nonwoven fabric, a battery negative electrode, a paint, a building material, furniture, or an electric product housing.

That is, the fine particle group B of the present invention can be classified into functions according to functions, as an anti-slip member, an antistatic member, a visible light blocking member, an ultraviolet blocking member, a strength reinforcing member, a flame retardant imparting member, a coloring member, a waterproof member, and the like. Useful.
In addition, since the fine particle group B of the present invention has many excellent physical properties due to carbon fibers, the carbon fibers themselves can be filled in an already used product (application) and reused. .

The fine particle group B of the present invention can be formed into a film, a sheet, or a structure by adding a binder resin to the epoxy resin (raw material matrix resin) derived from the raw material contained therein, and further adding a binder resin later.
Such binder resins are not particularly limited, but include hard polyvinyl chloride, soft polyvinyl chloride, thermoplastic polyurethane, polyamide, polyester, polycarbonate, ethylene vinyl acetate copolymer (EVA), polyethylene, polypropylene, poly (meth) acrylate, and polystyrene. And thermoplastic resins such as copolymers thereof; and thermosetting resins such as epoxy resins, unsaturated polyesters, phenolic resins and polyimides.

Since the fine particle group B of the present invention can adjust the particle size distribution for each application, for example, the fine particle group B having a particle size distribution of 1 μm or more and 30 μm or less is used for filling particles for a film having a film thickness of 40 μm or less, for a fiber material, It can be suitably used for a battery negative electrode material or as a dispersed particle for a paint.
Specifically, it is preferably used as a filler particle in a film such as an electromagnetic wave shielding film, an electronic substrate shielding cover film, a conductive film, a metal oxidation preventing film, an agricultural multi-film, a transparent member smoke film, and an antistatic film. Can be used.
Further, it can be suitably used as a material for fibers such as an agricultural non-woven fabric, a speaker non-woven fabric and an insect net.
Further, it can be suitably used as a battery negative electrode material instead of graphite. Further, it can be suitably used as a dispersed particle for paints such as conductive paints, antistatic paints and antioxidant paints.

  The fine particle group B having a large particle size of 5 μm or less (distributed on the small particle size side) is particularly a particle filled in a film such as an electromagnetic wave shielding film, an electronic substrate shielding cover film, a conductive film, and a film for preventing metal oxidation. Can be suitably used.

Further, since the particle size distribution of the fine particle group B of the present invention can be adjusted for each application, for example, the fine particle group B having a particle size distribution of 3 μm or more and 120 μm or less has a thickness of 1000 μm or less (preferably a 100 μm or less sheet). ), For dispersed particles for paints, for filled particles for building materials or furniture, or for filled particles for housings of electric appliances.
Specifically, it can be suitably used as a filler particle for sheets such as a conductive sheet, a heat conductive sheet, a snow melting sheet, a ground heating sheet (such as a livestock hut), an anti-slip sheet, and an anti-static sheet. In addition, it can be suitably used as a dispersed particle for paints such as rust preventive paints, anticorrosive paints, and heat resistant paints. Further, it can be suitably used as a reinforcing material such as a fortified composite material (casting press method), a reinforcing material such as a lightweight and reinforced plate (by extrusion molding), and a rail for furniture. Further, it can be suitably used as a filling particle for a housing of an electric product such as a housing of a home appliance.

  In addition, those generally used as carbon fiber reinforced plastic (CFRP) are also suitably used as filler particles. As such, specifically, (a part of) sports equipment such as, for example, golf club shafts, tennis racket frames, fishing rods; various parts of vehicles such as automobiles, bicycles, airplanes, and ships; Musical instruments, portable goods, and fragile cases; and the like.

  As described above, in the film, sheet, structure, etc., in addition to the fine particle group B of the present invention and the binder resin, a plasticizer of the binder resin, a dispersant of the fine particles, a heat stabilizer, a foaming agent, a coloring agent, Lubricants, antistatic agents, other inorganic or organic fillers, flame retardants / flame retardants, surfactants, release agents, thickening stabilizers and the like can be contained. Each of these may be used alone or in combination of two or more.

The method for producing the film, sheet, structure, and the like described above is not particularly limited, and is determined based on the structure and physical properties of the binder resin. Known methods can be used, but before the fine particle group B of the present invention is blended. It is also preferable that a sol compound containing a binder resin, a plasticizer, a dispersant, and the like be prepared in advance and the fine particle group B of the present invention be blended therein. It is also preferable to mix some of the above components in advance and then mix and mix the other components. It is also preferable to dissolve and disperse in a solvent / dispersant before mixing.
For preparation and mixing, a known device such as a stirrer can be used, and the device is not limited, but can be produced by a known method. For example, it is produced by solventless molding; distilling and drying the solvent or dispersant after coating with a solvent or dispersant; removing after pouring into a mold; spraying; Furthermore, you may bake after forming and forming a coating film.

  Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples as long as the gist of the present invention is not exceeded.

Example 1
<Crushing process>
From the carbon fiber reinforced plastic (CFRP) which has been a waste material, 5 kg of the carbon fiber-containing epoxy resin body is about 0.7 cm to about 2 cm by using a cutter mill (manufactured by Makino Sangyo Co., Ltd., small low-speed crusher GSL). Crushed to a corner.
Here, the carbon fiber-containing epoxy resin body used as a raw material is obtained by forming a carbon fiber into a plate-like layer, infiltrating a thermosetting epoxy resin as a matrix resin therein, and thermosetting under pressure. And 85 parts by mass of carbon fiber and 15 parts by mass of a thermosetting epoxy resin.

<Pulverization process>
Next, the obtained “crushed product containing 85 parts by mass of carbon fibers and 15 parts by mass of a thermosetting epoxy resin” is put into a crusher using a hopper 12 or the like. As a pulverizer, an air current pulverizer (Cyclone Mill 400S, manufactured by Shizuoka Plant Co., Ltd.) was used and pulverized at room temperature (25 ° C.) under conditions in the normal range of the air current pulverizer to obtain fine particles.

The airflow pulverizer 11 has two impellers 14 having a diameter of 150 mm inside the apparatus. Large particles are coarsely pulverized by the first impeller 14 and moved to the second impeller 14 side. In the (high-speed) swirling airflow around the first and second impellers 14, they collide with each other and are pulverized. That is, the particles to be pulverized are mainly collided with each other by the swirling airflow and pulverized.
Further, the airflow crusher 11 has a classification function inside the apparatus, and the classified coarse powder is crushed again inside, and the classified fine powder can be taken out, that is, the classification is performed by centrifugal force. The fine powder thus obtained was taken out by the airflow of the blower.

At the time of pulverization, the interval D between the two impellers 14 of the airflow pulverizer 11 was set to 30 mm, the rotation speed of the impeller 14 was 8000 rpm, and the peripheral speed at that time was 168 m / s.
The collision between the particles to be pulverized and the impeller 14 is small, and since the particles are mainly pulverized by collision between the particles and cooled by a large amount of airflow, the temperature rise of the particles during the pulverization is suppressed. I couldn't see it.

FIG. 4A shows the particle size distribution of the obtained fine particle group B. The particle size distribution of the obtained fine particle group B (range in which 80% is included) was 1 μm or more and 200 μm or less. The volume average particle size of the fine particle group B was 70 μm. FIG. 4B shows the particle size distribution of the broad fine particle group similarly obtained by using another CFRP than in Example 1.
The particle size distribution and the average particle size in the present invention are defined as those measured by a wet method using a laser diffraction / scattering type particle size distribution measuring device Microtrack manufactured by Nikkiso Co., Ltd. and measured by the measuring device (method). You. All are distributions or average particle diameters based on volume (mass).

The carbon fibers of the carbon fiber-containing epoxy resin body as the raw material were not exposed on the surface of the obtained fine particles, and the carbon fibers were covered with the epoxy resin.
Further, from the beginning to the end of the pulverization, the fibrous carbon fibers were not separated and taken out (discharged) from the airflow pulverizer 11.

<Recovery process>
The fine particle group B obtained in the above-mentioned pulverizing step was collected in the final collection container 25 using a cyclone device 21 as schematically shown in FIG.
The cyclone device 21 was equipped with the transfer pipe 22, the cyclone part 23, the damper 24, and the final collection container 25 in this order from the side of the airflow crusher 11. The diameter at the midpoint of the height of the cyclone part 23 was 150 mm, the height was 300 mm, and the volume was L.

  The fine particle group obtained in the pulverizing step was supplied to the cyclone device 21 at a rate of 3 kg / min. The crushing speed was adjusted to such a speed, and the fine particles were transferred from the airflow crusher 11 to the cyclone device 21 through the transfer pipe 22.

FIG. 4C shows the particle size distribution of the obtained fine particle group B. The particle size distribution of fine particle group B (a range in which 80% is included) was 2 μm or more and 300 μm or less, and the CER was 7.0% by mass. FIGS. 4D and 4E show the particle size distribution of the fine particle group B similarly obtained by using a different CFRP from that of Example 1, and FIG. Is the particle size distribution of the fine particle group B similarly obtained by using another cyclone apparatus.
FIG. 3 shows a scanning electron microscope (SEM) photograph of the fine particle group B.

  The ultrafine particle group C that could not be captured by the cyclone device 21 was collected by an ultrafine particle collection device 41 having a dust collector 42 using a bag filter. The particle size distribution of the obtained ultrafine particle group C was less than 1 μm, and the CER was 98% by mass.

Example 2
Using an apparatus shown in FIG. 1 and FIG. 2 using the “carbon fiber-containing epoxy resin body containing 85% by mass of carbon fiber and 15% by mass of epoxy resin”, which is a recycled carbon fiber reinforced plastic (CFRP), Except for the conditions, a fine particle group B was produced in the same manner as in Example 1.
That is, in the pulverizing process, three types of fine particle groups B were produced by varying the conditions relating to the impeller 14 in the following three stages. However, the condition of the impeller of << condition 2 >> was the same as in Example 1.

<< Condition 1 >>
Rotation speed: 10000 rpm
Peripheral speed: 209 [m / s]
Impeller gap: 40mm
<< Condition 2 (same as Example 1) >>
Rotation speed: 8000 rpm
Peripheral speed: 168 [m / s]
Impeller gap: 30mm
<< Condition 3 >>
Rotation speed: 5000 rpm
Peripheral speed: 105 [m / s]
Impeller gap: 20mm

The “epoxy resin content (CER)” of the resulting fine particle group B is shown below.
Under condition 1, the CER is not more than 2.5% by mass. Under condition 2, the CER is not more than 7.0% by mass. Under condition 3, the CER is not more than 12% by mass.

The same operation as described above was repeated five times while changing the batch, and the range of “epoxy resin content (CER)” was determined. The results are shown below.
In condition 1, the CER is 0.5% by mass or more and 5% by mass or less In condition 2, the CER is 5% by mass or more and 10% by mass or less In condition 3, the CER is 10% by mass or more and 15% by mass or less Particle group B It has been found that the proportion of the epoxy resin covering the carbon fiber can be adjusted according to the use of the resin.

Comparative Example 1
The pulverization was performed in the same manner as in Example 1 except that a crusher mill, a pin mill, a cutter mill, a hammer mill, or an axial mill was used in place of the airflow pulverizer 11 used in Example 1, but each was pulverized. Under the usual grinding conditions of the apparatus, it was difficult to grind the main particle size to 100 μm or less.
In addition, attempts were made to form fine particles over a long period of time, but the temperature of the particles was excessively increased, or the particles could not be suitably pulverized. In addition, there were particles having no rounded particle shape and exposed carbon fibers. Therefore, a suitable fine particle group B could not be produced.

Comparative Example 2
The pulverization was performed in the same manner as in Example 1 except that a jet mill was used instead of the airflow pulverizer 11 used in Example 1. Although the particle size distribution of the fine particle group was almost the same as in Example 1, the cost was increased because the pulverization efficiency was extremely poor.
In addition, since the carbon fibers were exposed or the carbon fibers became fibrous and were taken out (discharged), even sampling was dangerous, and fine particles could not be produced without danger, and there was no danger. Fine particles could not be produced.

Example 3
<Production of structure containing fine particle group>
A sol compound having the following formulation containing "polyvinyl chloride having a polymerization degree of 860 obtained by emulsion polymerization" as a binder resin was prepared. Hereinafter, polyvinyl chloride may be abbreviated as “PVC”.

[Sol compound formulation]
Binder resin: Paste resin of PVC (degree of polymerization 860) 100.0 parts by mass Plasticizer: Diisononyl Phthalate (DINP) 35.0 parts by mass Dispersant: Higher fatty acid type, sorbitan monooleate 0.5 parts by mass Dispersant : Aliphatic hydrocarbon / carboxylic acid derivative carboxylic acid-based dispersant (BYK5125, manufactured by BYK) 0.5 part by mass Blowing agent: azodicarbonamide (manufactured by Otsuka Pharmaceutical Co., Ltd.) 2.0 parts by mass

30 parts by mass of the fine particle group B obtained in Example 1 was added to 100 parts by mass of the sol compound, and the mixture was stirred for 30 seconds with a mixer manufactured by ASONE Corporation.
The stirred “fine particle mixed sol compound” was coated on a backing paper for wallpaper with a thickness of 0.8 mm, placed in a normal air oven, and heated (baked) at 200 ° C. for 60 seconds. Became. Next, by cooling to room temperature, a 2 mm-thick “structure that is a foamed coated film-like (layered) foamed PVC sheet” containing the fine particle group B was obtained.

Evaluation example 1
The structure (sheet) obtained in Example 3 was evaluated as follows. The evaluation results are also described below.

<Dispersibility>
The evaluation was performed in the state of a “fine particle mixed sol compound”.
A double groove grind meter manufactured by Daiyu Co., Ltd. was used to check for any aggregates.
As a result, there was no aggregate, and the particle size distribution of the fine particle group B used was maintained.

<Bubble burn, discoloration, uneven color>
A test piece (150 mm × 150 mm × 2 mm in thickness) of the structure (sheet) was visually observed from above.
As a result, any of foaming burn, discoloration, and color unevenness could not be confirmed. No burning due to heat storage was observed. The coarse particles in which the fine particles were aggregated could not be detected visually.
The center and four corners of the sheet were measured with a colorimeter manufactured by Konica Minolta, Inc.
As a result, the color difference ΔE was within 0.2 (a color difference that cannot be determined with the naked eye).

<Color development>
Regarding the color development of the structure (sheet), a fixed color development (color development from black to dark gray) was obtained by adjusting the content of fine particles and the like and controlling the color tone for each lot.

<Fragility>
A test piece (150 mm × 150 mm × 2 mm thick) of the structure (sheet) was bent outward by 90 ° to check whether a crack was formed on the surface.
As a result, four cracks having a length of 3 mm were confirmed at the center, but it was determined that there was no problem because the cracks were not normally bent by 90 °.
If there is non-dispersion even in a normal processed pigment, such pinholes and cracks caused by such pinholes are generated, so it was considered that there was no problem in the fine particles themselves.

<Bleedability>
A “sol compound sheet” for evaluation was produced in the same manner as in the production of the structure (sheet) of Example 3 except that a mirror-surface iron plate was used to produce a sol compound containing no fine particles.
A test piece (150 mm × 150 mm × 2 mm in thickness) of the structure (sheet), which is the foamed PVC sheet obtained in Example 3, was sandwiched between the sheets, and was heated at 60 ° C. at 120 ° C. using a heating and pressing press. For 10 minutes, a weight of 10 kgf was applied.
After release, it was confirmed whether or not the black color of the carbon fibers in the fine particles in the structure (sheet) of Example 3 was transferred to the sol compound sheet.
As a result, no black color was visually observed.

Example 4
<Evaluation of fine particles B as “filled particles” for “sheet having a thickness of 70 μm”>
5 parts by mass of the fine particle group B obtained in Example 1, 1 part by mass of a sodium salt of carboxymethyl cellulose, 1 part by mass of a sodium salt of a polymethacrylic acid copolymer, and 15 parts by mass of a styrene-methacrylic acid copolymer. The mixture was charged into 70 parts by mass of N-methyl-2-pyrrolidone as a solvent, stirred with a magnetic stirrer, and then dispersed with a ball mill for 3 hours.
The obtained dispersion was applied onto a polyethylene terephthalate (PET) film using a bar coater so as to have a dry film thickness of 70 μm, and dried at 80 ° C. (the solvent was distilled off) to obtain a sheet.

The obtained sheet was useful as a conductive sheet, an antistatic sheet, and the like because of its large surface and bulk conductivity.
In addition, the obtained sheet is excellent in thermal conductivity and mechanical strength, and is excellent in absorbing radiant heat because it is black, so it is extremely useful as a heat conductive sheet, snow melting sheet, ground heating sheet, slip prevention sheet, etc. Was useful.

Example 5
<Evaluation of fine particles B as “filled particles” for “sheet having a thickness of 70 μm”>
A dispersion was obtained in the same manner as in Example 4, except that “15 parts by mass of the styrene-methacrylic acid copolymer” in Example 4 was changed to “15 parts by mass of the main component of the epoxy resin”.
Thereafter, 3 parts by mass of a curing agent of an epoxy resin was added, and after stirring well, a sheet having a thickness of 70 μm was obtained.

The obtained sheet was useful as a conductive sheet, an antistatic sheet, and the like because of its large surface and bulk conductivity.
In addition, the obtained sheet is excellent in thermal conductivity and mechanical strength, and is excellent in absorbing radiant heat because it is black, so it is extremely useful as a heat conductive sheet, snow melting sheet, ground heating sheet, slip prevention sheet, etc. Was useful.

Example 6
<Evaluation of fine particles B as “filled particles” for “sheet having a thickness of 70 μm”>
Using the fine particle group B obtained in Example 1 and polypropylene as a binder, the mixture was heated without solvent and kneaded with a three-roll mill to disperse the fine particle group B, and a sheet having a thickness of 70 μm was obtained according to a conventional method.
The obtained sheet is black, absorbs radiant heat, is excellent in strength, and is inexpensive, and thus was extremely useful as a snow melting sheet, a ground heating sheet, an anti-slip sheet, an antistatic sheet, and the like.

Example 7
<Evaluation of Fine Particle Group B as Dispersed Particles in Paint>
The dispersions of Examples 4 and 5 containing the fine particle group B obtained in Example 1 can be used as a paint or a base material of the paint by blending a compounding agent or the like according to the application.

Further, 7 parts by mass of the fine particle group B obtained in Example 1, 15 parts by mass of a novolak type epoxy oligomer, and 4 parts by mass of sedimentable barium sulfate were stirred by a stirrer, and then dispersed by a ball mill for 3 hours.
By mixing (by combining) the obtained dispersion with an epoxy curing agent, excellent rust preventive paint, anticorrosive paint, heat resistant paint and the like can be provided.

Example 8
<Evaluation of Fine Particle Group B as Dispersed Particles in Paint>
A dispersion was obtained in the same manner as in Example 7, except that toluene diisocyanate was used instead of the novolak epoxy oligomer.
By mixing the obtained dispersion with a curing agent containing a polyhydric alcohol, excellent rust preventive paints, anticorrosive paints, heat-resistant paints and the like could be obtained.

Example 9
<Evaluation of fine particle group B as packing particles for housings of building materials, furniture, and electrical products>
By using styrene-butadiene rubber, elastomer, polyurethane, polyamide, polyphenol, polyester, and polycarbonate as binders, reinforced building materials and automotive materials such as “Forged Composites (registered trademark), casting press method”, and “furniture” , "Electric product housing" was obtained.
They can be extruded, and have achieved weight reduction, high strength, and low cost.

Example 10
The fine particle group B obtained in Example 1 was classified using a cyclone classifier to obtain a fine particle group B ′ having a particle size distribution of 30 μm or less. In the following examples, as the “fine particle group B”, the fine particle group B ′ having a small particle size distribution obtained here was used.

Example 11
<Evaluation of Fine Particle Group B ′ as Filled Particles for “Film with 40 μm Thickness”>
5 parts by mass of fine particle group B 'obtained in Example 10, 1 part by mass of sodium salt of carboxymethyl cellulose, 1 part by mass of sodium salt of polymethacrylic acid copolymer, 15 parts by mass of styrene-methacrylic acid copolymer Was added to 70 parts by mass of N-methyl-2-pyrrolidone as a solvent, stirred with a magnetic stirrer, and then dispersed for 3 hours with a ball mill.
The resulting dispersion was applied on a polyethylene terephthalate (PET) film using a bar coater to a dry film thickness of 40 μm, and dried at 80 ° C. (solvent was distilled off) to obtain a conductive film. .

  The obtained conductive film had a large surface conductivity, and was useful as an electromagnetic wave shielding film, an electronic substrate shielding cover film, a metal oxidation preventing film, and an antistatic film.

Example 12
<Evaluation of Fine Particle Group B ′ as Filling Particles for “Film with a Film Thickness of 40 μm”>
A dispersion was obtained in the same manner as in Example 11, except that “15 parts by mass of the styrene-methacrylic acid copolymer” in Example 11 was changed to “15 parts by mass of the main component of the epoxy resin”.
Thereafter, 3 parts by mass of a curing agent of an epoxy resin was added, and the mixture was sufficiently stirred, and then applied on a polyimide film using a bar coater to a dry film thickness of 40 μm to obtain a conductive film.

  The obtained conductive film was extremely useful as an electromagnetic wave shielding film, an electronic substrate shielding cover film, a film for preventing metal oxidation, an antistatic film, a transparent conductive film, and the like because of its large surface conductivity.

Example 13
<Evaluation of Fine Particle Group B ′ as Filled Particles for “Film with 40 μm Thickness”>
The used amount (parts by mass) of the fine particle group B ′ obtained in Example 10 was appropriately adjusted, and the fine particle group B ′ was dispersed by using polypropylene as a binder, heating without solvent, and kneading with a three-roll mill.
The film was cast to a film thickness of 40 μm and cooled to obtain a film.

The resulting film was black, absorbing solar heat, and not transmitting sunlight, thereby suppressing the growth of weeds, and was useful as an agricultural mulching film.
Also, by reducing the amount (parts by mass) of the fine particle group B ′, it was useful as a smoke film for a transparent member.

Example 14
<Evaluation of Fine Particle Group B 'as Filling Particles for "Fibers and Nonwovens">
5 parts by mass of the “fine particle group B ′ obtained in Example 10” was kneaded with 20 parts by mass of polyethylene terephthalate, and then fiberized according to a conventional method to obtain a fiber. The obtained fiber was useful as a fiber of a nonwoven fabric to be described later, as a fiber for an insect-proof net, and the like.

  The fiber obtained above was made into a nonwoven fabric according to a conventional method. Since the nonwoven fabric had high mechanical strength and blackness, it was useful as a heat insulating nonwoven fabric for agricultural use and a nonwoven fabric for speakers.

Example 15
<Evaluation of fine particle group B ′ as packing particles for packing>
The fine particle group B ′ obtained in Example 10 was heated and kneaded together with a silicone resin to obtain a packing for stopping electric water. The obtained packing for waterproofing electric materials had excellent strength and water resistance.

Example 16
<Evaluation of Fine Particle Group B 'as Negative Electrode (Material)>
The fine particle group B ′ obtained in Example 10 was added to a carbonaceous material (such as graphite particles) and molded to obtain a negative electrode of a lithium ion secondary battery. Since a suitable conductive network can be formed, by using it as a negative electrode, a lithium ion secondary battery having excellent battery characteristics can be provided.

  The above electrode is useful as a negative electrode (anode) for a lithium secondary battery, and also useful as a negative electrode (anode) for a fuel cell, a negative electrode (cathode) for an electrolytic cell, and the like.

Example 17
<Evaluation of Fine Particle Group B ′ as Dispersed Particles in Paint>
The dispersions of Examples 11 and 12 containing the fine particle group B 'obtained in Example 10 can be used as a paint or a base material of a paint by further blending a compounding agent suitable for the intended use therewith. Can be.

7 parts by mass of the fine particle group B ′ obtained in Example 10, 1 part by mass of a sodium salt of carboxymethyl cellulose, 1 part by mass of a sodium salt of a polymethacrylic acid copolymer, 15 parts by mass of a novolak-type epoxy oligomer, After stirring 4 parts by mass of the silica powder with a stirrer, the mixture was dispersed with a ball mill for 3 hours.
The resulting dispersion is mixed with an epoxy curing agent and applied to a substrate. The resulting film exhibits excellent conductivity, waterproofness, and strength. It was extremely useful as a paint, a waterproof paint and the like.

Example 18
<Evaluation of Fine Particle Group B ′ as Dispersed Particles in Paint>
A dispersion was obtained in the same manner as in Example 17, except that toluene diisocyanate was used instead of the novolak epoxy oligomer.
The resulting dispersion is mixed with a curing agent containing a polyhydric alcohol and applied to a substrate, and the resulting film exhibits excellent conductivity, waterproofness, and strength. It was useful as an antioxidant paint, an antioxidant paint, a waterproof paint and the like.

The method for producing a fine particle group of the present invention can use a carbon fiber-containing epoxy resin body which is CFRP as a raw material, can be recycled as a useful compound to be blended with a binder resin or the like, and contains substantially bare carbon fibers. And the surface is coated with the matrix resin in the raw material, which is excellent in safety and physical properties. Further, since the CER can be manufactured (crushed) by adjusting the CER to a suitable range, manufacturing of resin compounds, films, sheets, carbon fiber-containing structures, paints, so-called castings, building materials / furniture, containers / housings, electrodes, etc. It is widely used in the field or use field; in the field of waste treatment;
The fine particle group of the present invention can be adjusted to a “preferred CER” having a wide field of application, and can have a suitable particle size distribution, so that it can be regarded as a black pigment, a processed pigment, an extender pigment, a filler, and the like. They are widely used in the fields where they are used.

REFERENCE SIGNS LIST 11 air flow crusher 12 hopper 13 motor 14 impeller 20 recovery device 21 cyclone device 22 transfer pipe 23 cyclone site 24 damper 25 final recovery container 41 ultrafine particle recovery device 42 dust collector A crushed material B fine particle group C ultrafine particle group D impeller distance R impeller Rotation S suction

Claims (12)

When the carbon fiber-containing epoxy resin body is pulverized to produce a fine particle group that is an aggregate of fine particles coated with an epoxy resin around the carbon fiber, the content ratio of the carbon fiber and the epoxy resin in the fine particles is determined. A method for producing a group of fine particles such that the epoxy resin content (CER [% by mass]) represented by the following formula (1) has a specific value:
When the carbon fiber-containing epoxy resin body is pulverized using a “air current pulverizer having two or more impellers and crushing particles to be pulverized by a swirling air flow generated by rotation of the impeller”, the impeller The epoxy resin content (CER [mass%]) is reduced (increased) by increasing (decreasing) the rotational speed or the peripheral speed of the impeller and / or increasing (narrowing) the impeller interval between the two impellers. A method of producing a group of fine particles.
CER [% by mass]
= 100 x [mass of epoxy resin in particle group (g) / [mass of particle group (g)]
... (1)   The epoxy resin content (CER [% by mass]) of the manufactured fine particle group is higher than the content ratio [% by mass] of the epoxy resin contained in the carbon fiber-containing epoxy resin body with respect to the entire carbon fiber-containing epoxy resin body. The method for producing a group of fine particles according to claim 1, which is small.   The method for producing fine particles according to claim 1 or 2, wherein the impeller of the air-flow crusher is crushed by adjusting the rotation speed of the impeller within a range of 3000 rpm or more and 14000 rpm or less.   The method for producing fine particles according to any one of claims 1 to 3, wherein pulverization is performed by adjusting a peripheral speed of an impeller of the airflow pulverizer within a range of 60 m / sec or more and 300 m / sec or less.   The method for producing fine particles according to any one of claims 1 to 4, wherein pulverization is performed by adjusting an interval between impellers of the airflow pulverizer within a range of 15 mm or more and 60 mm or less.   The production of the fine particle group according to any one of claims 1 to 5, wherein the carbon fiber-containing epoxy resin body is pulverized using the airflow pulverizer, and then the fine particle group is recovered using a cyclone device. Method.   The method for producing a fine particle group according to any one of claims 1 to 6, wherein the fine particle group is produced so that the average particle diameter is 1 µm or more and 120 µm or less.   Using a dust collector, the average particle diameter is smaller than the fine particles contained in the fine particle group, and the epoxy resin content (CER [% by mass]) is the epoxy resin content of the fine particle group (CER [% by mass]). The method for producing a group of fine particles according to claim 1, wherein the ultrafine particles (group) are collected.   By mixing two or more types of fine particles having different epoxy resin contents (CER [% by mass]) obtained by the method of manufacturing fine particles according to any one of claims 1 to 8, A method for producing a fine particle group, comprising adjusting an epoxy resin content (CER [% by mass]).   A fine particle group obtained by using the method for producing a fine particle group according to any one of claims 1 to 9, wherein the content of the epoxy resin (CER [CER [ Mass%]) is from 0.5% by mass to 15% by mass.   A method of manufacturing a fine particle group according to any one of claims 1 to 9, wherein the fine particle group is filled in a resin, laminated or molded, or dispersed in a dispersion medium. A method for producing a film, sheet, nonwoven fabric, battery negative electrode, paint, building material, furniture, or electrical product housing. 11. The filler according to claim 10, wherein the filler is for a film or a sheet, for a nonwoven fabric material, for a battery negative electrode material, or for a dispersion particle for a paint, for a filler particle for a building material or furniture, or for a filler particle for a housing of an electric product. The microparticles described.