JP2002095943A - Dispersion method and dispersion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dispersion method and a dispersion device with a simple structure capable of dispersing much capacity of dispersion well, hardly influenced by a temperature and a humidity of an outer surrounding. SOLUTION: In the dispersion method of the present invention, a closed dispersion container in which a viscous liquid 3 and an additive 4 are mixed is placed on a hollow inner surface 1a of a hollow cylindrical outer rotation body 1 making a rotation axis as a horizontal direction. The outer rotation body 1 is rotated and a container is rotated by interlocking with a rotation of the outer rotation body 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a dispersion method and a dispersion apparatus for dispersing an additive in a viscous liquid.

[0002]

2. Description of the Related Art In an electrophotographic image forming apparatus such as a copying machine, a printer, and a facsimile, parts such as a charging roller, a developing roller, a transfer belt, and a fixing roller are used. These components are composed of resistance control,
For the purpose of controlling thermal conductivity, improving durability, improving abrasion resistance, etc., various fine particulate additives are dispersed and produced.

Conventionally, the dispersion method includes a sand mill stirring dispersion method, a desktop ball mill dispersion method, an ultrasonic dispersion method, and a centrifugal stirring dispersion method utilizing rotation and revolution.

[0004]

However, in the sand mill stirring and dispersing method, there is a disadvantage that the object to be dispersed (resin / additive mixture) is a so-called open system which is open to the surroundings and is easily affected by the external environment temperature and humidity. is there. Although a cooling device is used to prevent a rise in temperature due to high-speed rotation, the cooling water used in the cooling device raises the ambient humidity, and there is also a disadvantage that a solvent having high hygroscopicity cannot be used. In addition, the used disks, sands, and balls have complicated shapes, and thus have a disadvantage that maintenance is difficult.

In a dispersion method using a table-top ball mill,
Since the rotation speed of the container in which the object to be dispersed is enclosed cannot be so high, it is difficult to obtain good dispersion performance.

[0006] Ultrasonic dispersion cannot be performed well unless the positional relationship between the ultrasonic wave transmitter and the object to be dispersed is appropriate, and is not suitable when the capacity of the object to be dispersed is large.

In the centrifugal stirring and dispersion, there is a disadvantage that the apparatus becomes complicated because a mechanism for rotating and revolving is required. A dispersant having a large specific gravity, such as ITO or metal powder, has a disadvantage that it is settled if left after dispersion. In addition, since the device rotates at a high speed, the device generates a large amount of heat, so that the thermosetting resin or the like cannot be dispersed for a long time, which is not suitable for mass production.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has a simple structure, a large-capacity dispersion which can be satisfactorily affected by the temperature and humidity of the outside environment. It is an object to provide a dispersing device.

[0009]

In order to solve the above-mentioned problems, a dispersion method according to a first aspect of the present invention comprises mixing a viscous liquid and an additive in a container, and mixing the additive in the viscous liquid. In the dispersion method of uniformly dispersing the, in the hollow inner surface of the hollow cylindrical outer rotating body having a horizontal axis of rotation, a viscous liquid and additives are mixed and placed in a sealed dispersion container,
The outer rotating body is rotated, and the container is rotated in conjunction with the rotation of the outer rotating body.

[0010] According to the first aspect of the present invention, the apparatus is not affected by the temperature and humidity of the external environment, has a simple structure, and is excellent in quality.
Large capacity dispersion can be performed.

According to a second aspect of the present invention, there is provided the dispersing method according to the first aspect, wherein the dispersion container has a cylindrical shape having an outer diameter equal to or less than the hollow inner diameter of the outer rotating body. I do.

According to the second aspect of the present invention, since the dispersion container is cylindrical, dispersion can be performed smoothly while maintaining rolling contact with the hollow inner surface of the outer rotating body.

According to a third aspect of the present invention, in the dispersion method of the second aspect, a cylindrical rotor having a circumferential spiral groove formed on a surface thereof is charged into a dispersion container and hermetically sealed. The outer rotating body is rotated.

According to the third aspect of the present invention, the rotor having the circumferential spiral groove formed on the surface is also charged into the dispersion container and sealed, so that the dispersibility is further improved or the dispersion is improved. Time can be reduced.

According to a fourth aspect of the present invention, there is provided the dispersing method according to the first to third aspects, wherein the outer rotating body is rotated while heating the dispersing container.

According to the fourth aspect of the invention, the viscosity of the viscous resin can be reduced to improve the dispersibility or shorten the dispersion time.

A dispersing method according to a fifth aspect is characterized in that, in the dispersing method according to the first to fourth aspects, the outer rotating body is rotated while changing the number of rotations.

According to the fifth aspect of the present invention, since the rotation speed of the outer rotating body is changed, it is possible to promote the dispersion while changing the state of the viscous liquid and the additive so as not to be in a steady state. it can. Further, there is no possibility that the viscous liquid and the additive are centrifugally separated and adhere to the inner wall of the container.

According to a sixth aspect of the present invention, in the dispersion apparatus, a hollow cylindrical outer rotating body having a rotation axis in a horizontal direction, a viscous liquid and an additive mixed therein are hermetically sealed, and a hollow inner surface of the outer rotating body is provided. And a rotating means for rotating the outer rotating body.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a distribution apparatus according to the present invention will be described with reference to the drawings.

FIGS. 1A and 1B are schematic sectional views of a dispersion apparatus used in the dispersion method according to the present invention.
FIG. 1A is a side sectional view, and FIG. 1B is a front sectional view.

In FIG. 1, reference numeral 1 denotes a hollow cylindrical outer rotating body whose rotation axis is horizontal. A motor 7 as a rotating means is connected to the outer rotating body 1 via a belt 8 and a pulley 9, and the motor 7 is controlled by control means (not shown) to change the number of rotations while rotating the outer rotating body 1. Can be rotated.

On the hollow inner surface 1 a of the outer rotating body 1, a cylindrical dispersion container 2 is placed with its axial direction coinciding with the axial direction of the outer rotating body 1. Inside the dispersion container 2,
A viscous liquid 3 as an object to be dispersed and an additive 4 are mixed therein, and a rotor 5 is also charged and hermetically sealed.

The viscous liquid 3 is, for example, a thermoplastic resin raw material such as a polyamideimide solution which is used as a material for a charging roller and a transfer belt of an image forming apparatus. Additive 4 is
A viscous liquid 3 for the purpose of resistance control or thermal conductivity control
, Such as carbon black and titanium oxide fine powder.

As will be described later, the rotor 5 rotates in the dispersion container 2 with the rotation of the outer rotating body 1 to improve the dispersibility of the viscous liquid 3 and the additive 4. , A substantially cylindrical member having a circumferential spiral groove formed on the surface.

A heater 6 is provided near the outside of the outer rotating body 1, and when the viscous liquid 3 has thermoplasticity,
The viscous liquid 3 is heated to reduce its viscosity and improve dispersibility.

Next, a dispersing method using this dispersing apparatus will be described with reference to the drawings.

FIG. 2 is a flowchart of a distribution method using the distribution apparatus.

First, a viscous liquid 3 as an object to be dispersed and an additive 4 are mixed into a dispersion container 2 (S.1). Next, the rotor 5 is loaded with its axial direction coinciding with the axial direction of the dispersion container 2 (S.2). The rotor 5 is a substantially columnar member as shown in FIG. 3, and has a circumferential spiral groove 5a formed on the surface thereof. The rotator 5 is used for the dispersion container 2
When the viscous liquid 3 and the additive 4 are dispersed while being rotated, the dispersibility of the viscous liquid 3 and the additive 4 is improved.
And an additive 4 in the axial direction.

After the viscous liquid 3, the additive 4, and the rotor 5 are put in the dispersion container 2, the dispersion container 2 is sealed (S.
3). By sealing the dispersion container 2, the viscous liquid 3 and the additive 4 are hardly affected by the temperature and humidity of the external environment. For example, even when a highly water-absorbing solvent or the like is used,
It is possible to prevent the solid content from changing due to the absorption of moisture in the external air. In addition, since the container is sealed, there is no possibility that a highly volatile solvent or the like volatilizes.

After the dispersion container 2 is sealed, the dispersion container 2 is placed on the hollow inner surface 1a of the outer rotating body 1 with its axial direction coinciding with the axial direction of the outer rotating body 1 (see also S.4 and FIG. 1). Thereby, the axial direction of the dispersion container 2 and the axial direction of the rotor 5 become parallel to the axial direction of the outer rotating body 1 whose horizontal axis is the rotation axis.

As shown in FIG. 1B, the dispersion container 2 is located at the bottom of the hollow inner surface 1a of the outer rotating body 1 by its own weight.
The viscous liquid 3, the additive 4, and the rotor 5 in the dispersion container 2 are also located at the bottom of the inner wall of the dispersion container 2.

Next, the motor 7 is driven to rotate the outer rotating body 1 via the pulley 9 and the belt 8 (S.5). With the rotation of the outer rotating body 1, the dispersion container 2 placed on the hollow inner surface 1a rotates while maintaining rolling contact with the hollow inner surface 1a. At this time, the dispersion container 2 rotates while being positioned near the bottom of the hollow inner surface of the outer rotating body 1 by its own weight. As the dispersion container 2 rotates, the viscous liquid 3 and the additive 4 sealed therein are dispersed.

Further, as the dispersion container 2 rotates, the rotor 5 sealed therein also rotates. Here, since the circumferential spiral groove 5 a is formed on the outer peripheral surface of the rotor 5, the viscous liquid 3 and the additive 4 in the dispersion container 2 are stirred in the axial direction by the rotation of the rotor 5. When a force is applied, dispersion dispersion in the axial direction can be suppressed, and dispersibility can be further improved.

When the viscous liquid 3 is a thermoplastic resin raw material, the heater 6 is energized in order to reduce the viscosity by heating to further facilitate dispersion (S.6).

The number of rotations of the outer rotating body 1 is changed by changing the number of rotations of the motor 7 regularly or irregularly by means of a known inverter control or the like (S.
7). By changing the rotation speed of the outer rotating body 1, the dispersion state of the viscous liquid 3 and the additive 4 in the dispersion container 2 can also be changed, and the dispersion state becomes a steady state with dispersion dispersion. Can be prevented, and the dispersibility can be further improved.

In the dispersion of the viscous liquid 3 and the additive 4, the rotation speed of the dispersion container 2 is generally high,
Dispersibility improves as the centrifugal force acting on the viscous liquid 3 and the additive 4 therein increases.

As shown in FIG. 4, when the radius of the hollow inner surface 1a of the outer rotating body 1 is R, the rotation speed is ωR, and the outer radius of the dispersion container 2 is r, the rotation speed ωr of the dispersion container 2 is ωr = ω
It is given by R × R / r.

The centrifugal force Fr acting on the viscous liquid 3 and the additive 4 per unit mass in the dispersion container 2 is
Fr = ωr2 / r = ωR2 × R2 / r. That is, ωR (the rotation speed of the outer rotating body 1) and R /
As r (the radius ratio between the outer rotating body 1 and the dispersion container 2) increases, the rotation speed ωr of the dispersion container 2 can be increased, and the centrifugal force Fr acting on the viscous liquid 3 and the additive 4 also increases. And dispersibility can be improved.

Further, since the rotor 5 in the dispersion container 2 rotates at a high speed inside the container with the rotation of the dispersion container 2, a different rotational force and a different shear force are applied to each part of the viscous liquid 3 to be dispersed. Further, dispersibility can be improved.

Incidentally, a rubber layer such as urethane rubber or silicon rubber may be formed on the outer peripheral surface of the dispersion container 2 in order to increase the coefficient of friction with the hollow inner surface 1a of the outer rotating body 1.

Further, in this embodiment, one dispersion container is placed inside the outer rotating body, but when dispersing a plurality of different types of viscous liquids and additives, FIG.
As shown in (a) and (b), a plurality of dispersion containers 2 ′ may be placed in series or in parallel. This makes it possible to simultaneously disperse the viscous liquid and the additive in the plurality of dispersion containers, thereby shortening the dispersion time.

When a large amount of a viscous liquid and an additive are dispersed, the dispersion container can be easily changed to a large one.

Further, since a mold for forming a belt or the like can be used as the outer rotating body 1, for example, the cost of the apparatus can be reduced.

[Example 1] A holder having vent holes capable of sending and exhausting air was attached to both ends of a lathe-like horizontal rotation driving device (rotating means) having a rotation axis in the horizontal direction, and an aluminum material was attached to the holder. A rotation type (outside rotation body) having a hollow inner diameter of φ300 mm can be attached. Also, on the outside of the rotary type,
Attach a far-infrared external heater.

A solution (viscous liquid) of a polyimide precursor polyamic acid and carbon black (additive) are mixed into a plastic cylindrical container (dispersion container) of φ80 mm (capacity: 500 cc) filled with nitrogen gas in place of air beforehand. And seal.

One end of the rotary mold was fixed to the holder, the cylindrical container was inserted into the rotary mold from the other end, and the other end was fixed by the holder.

The rotation was started, and the rotation was continued at a rotation speed of 1000 rpm for about 30 minutes.

After that, the rotation was stopped, the cylindrical container inside the rotary mold was taken out, the dispersed solution was taken out from the inside of the cylindrical container, and applied to a flat plate of 1 m × 1 m, and dried and cured in a heating furnace to obtain a thick plate. A 50 μm thick film was obtained. There was no carbon dispersion unevenness or agglomeration, the appearance was smooth and good, and the variation in resistance value was as good as within one order over the entire film.

Example 2 A solution (viscous liquid) of a polyimide precursor polyamic acid and carbon black (added) were placed in a plastic cylindrical container (dispersion container) of φ80 mm (capacity: 500 cc) filled with nitrogen gas by replacing with air in advance. Agent) and hermetically sealed.

One end of a rotary mold (outer rotary body) similar to that of Example 1 was fixed to a holder, the cylindrical container was inserted into the rotary mold from the other end, and the other end was fixed by the holder.

The rotation was started, the rotation speed was once increased to 2000 rpm, then reduced to 100 rpm, and then the rotation was continued for approximately 20 minutes while periodically repeating the rotation speed of 2000 rpm and the rotation speed of 100 rpm.

Thereafter, the rotation was stopped, the cylindrical container inside the rotary mold was taken out, and the dispersed solution was taken out from the inside of the cylindrical container, applied to a flat plate of 1 mx 1 m, and dried and cured in a heating furnace to obtain a thick plate. A 50 μm thick film was obtained. There was no carbon dispersion unevenness or agglomeration, the appearance was smooth and good, and the variation in resistance value was as good as 0.7 order or less throughout the film.

Example 3 A thermoplastic polyamide-imide solution (viscous liquid) and titanium oxide fine powder (additive) were placed in a φ80 mm (capacity: 500 cc) plastic cylindrical container (dispersion container) filled with nitrogen gas by replacing with air in advance. )
And sealed.

One end of a rotary mold (outer rotary body) similar to that of Example 1 was fixed to a holder, the cylindrical container was inserted into the rotary mold from the other end, and the other end was fixed by the holder.

The rotation was started, and the rotation was continued at 1,000 rpm for 10 to 30 minutes. At that time, the dispersion state was compared between the case where the apparatus was rotated while heating with a far-infrared heater provided outside and the case where the apparatus was rotated without heating.

When heated, the temperature of the rotary mold is 100
The temperature was controlled by setting to ° C.

When the rotation was stopped, the cylindrical container inside the rotary mold was taken out, and the dispersed solution was taken out from the inside of the cylindrical container, and the state of the dispersion was observed. Although it was dispersed, non-uniformity was still observed after 20 minutes of rotation without heating, and rotation of 30 minutes or more was required to obtain uniformity of dispersion.

The uniformly dispersed solution was applied on a flat plate in an area of 1 mx 1 m, and dried in a heating furnace to obtain a film having a thickness of 50 µm. The conductive agent (titanium oxide fine powder) did not have dispersion unevenness, the appearance was smooth and good, and the variation in the resistance value was as good as 0.5 order or less in the entire region.

Example 4-1 A thermoplastic resin polyamide solution (a viscous liquid) and an indium oxide fine powder (a viscous liquid) were placed in a plastic cylindrical container (dispersion container) of φ80 mm (capacity: 500 cc) filled with nitrogen gas by replacing with air in advance. (Additives) and sealing.

One end of the same rotary mold (outer rotary body) as in Example 1 was fixed to a holder, the cylindrical container was inserted into the rotary mold from the other end, and the other end was fixed with the holder.

The rotation was started, the rotation was performed at a rotation speed of 1000 rpm, and the rotation was continued for 10 minutes while being heated by a far-infrared heater provided outside.

The rotation is stopped, the cylindrical container inside the rotary mold is taken out, and the dispersed solution is taken out from the inside of the cylindrical container, applied to a flat plate of 1 m × 1 m, dried in a heating furnace, and dried to a thickness of 50 μm. Was obtained. There was no uneven dispersion of the conductive agent (indium oxide fine powder), the appearance was smooth and good, and the variation in resistance value was as good as 0.5 order or less over the entire film.

Example 4-2 When the indium oxide dispersion uniformly dispersed in Example 4-1 was allowed to stand overnight in a cylindrical container, the indium oxide powder was precipitated at the bottom of the container. When the turbid liquid at the top of the container was applied in the same manner as in Example 4-1, the resistance value was increased by at least four orders of magnitude.

Then, the precipitation solution was again used in Example 4-1.
Then, the dispersed solution was taken out, applied to a flat plate in a size of 1 m × 1 m, and dried in a heating furnace to obtain a film having a thickness of 50 μm. This film also had no unevenness in dispersion of the conductive agent (indium oxide fine powder) and had a smooth and good appearance, and the variation in resistance was as good as 0.5 order or less throughout the film.

[Embodiment 4-3] In the above-described embodiment 4-1, the motor was rotated at a rotation speed of 1000 rpm, the rotation was continued for 10 minutes while heating with a heater, and then the heating was stopped and the rotation was stopped at a rotation speed of 100 rpm. The operation was continued overnight.

Thereafter, the rotation was stopped, the cylindrical container inside the rotary mold (outer rotary body) was taken out, and the dispersion solution in the container was observed. As a result, no precipitation of indium oxide powder was observed.

The dispersion solution was taken out from the inside of the cylindrical container, applied on a flat plate in a size of 1 m × 1 m, and dried in a heating furnace to obtain a film having a thickness of 50 μm. Conductive agent (indium oxide fine powder)
And the appearance was smooth and good, and the variation in resistance value was as good as 0.5 order or less throughout the film.

Example 5 A thermoplastic polyamide-imide solution (viscous liquid) and titanium oxide fine powder (added) were placed in a plastic cylindrical container (dispersion container) of φ80 mm (capacity: 500 cc) filled with nitrogen gas by replacing with air in advance. Agent), and a circumferential spiral groove (depth 5
cylindrical rotor with an outer diameter of φ
20 mm) and sealed.

One end of a rotary mold (outer rotary body) similar to that of Example 1 was fixed to a holder, the cylindrical container was inserted into the rotary mold from the other end, and the other end was fixed by the holder.

The rotation was started, the rotation was performed at a rotation speed of 1000 rpm, and the rotation was continued for 5 to 30 minutes.

The rotation was stopped, the cylindrical container inside the rotary mold was taken out, and the dispersion solution in the container was observed. As a result, the titanium oxide powder was uniformly dispersed by the rotation for 10 minutes without heating with a heater. . Furthermore, when rotated while heating with a heater, the particles were uniformly dispersed by rotation for 5 minutes.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a schematic structure of a dispersion apparatus according to an embodiment of the present invention, where (a) is a cross-sectional view as viewed from a side and (b) is a cross-sectional view as viewed from the front. .

FIG. 2 is a flowchart illustrating a distribution method using the distribution apparatus according to the embodiment of the present invention.

FIG. 3 is a schematic perspective view of a rotor used in the dispersion apparatus according to the embodiment of the present invention.

FIG. 4 is a schematic front cross-sectional view for explaining a dimensional relationship and the like of each part of the dispersion apparatus according to the embodiment of the present invention.

FIGS. 5A and 5B are perspective views showing a case where a plurality of dispersion containers are used, wherein FIG. 5A shows a case where dispersion containers are placed in series on a hollow inner surface of an outer rotating body, and FIG. In this case, the dispersion containers are placed side by side on the hollow inner surface.

[Explanation of symbols]

 Reference Signs List 1 outer rotating body 1a hollow inner surface 2 dispersion container 3 viscous liquid 4 additive 5 rotor 5a spiral groove 6 heater 7 motor (rotating means) 8 belt 9 pulley

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 15/08 501 G03G 15/08 501D 4G036 15/20 103 15/20 103 4G037 B29K 79:00 B29K 79: 00 F term (reference) 2H003 BB11 CC05 2H033 BA12 BB01 BB28 2H077 AD06 FA12 FA16 FA23 FA25 4F201 AA40 AB00 AB12 AB18 AK09 BA01 BC01 BC02 BC12 BC33 BC37 BK01 BK12 BK33 BK38 4G035 AB43 4G036 AA12 4G037

Claims (6)

[Claims] 1. A viscous liquid and an additive are mixed in a container,
In the dispersion method of uniformly dispersing the additive in the viscous liquid, the viscous liquid and the additive are mixed and hermetically sealed into a hollow inner surface of a hollow cylindrical outer rotating body having a rotation axis in a horizontal direction. A dispersing container mounted thereon, the outer rotating body is rotated, and the container is rotated in conjunction with the rotation of the outer rotating body. 2. The dispersion method according to claim 1, wherein the dispersion container has a cylindrical shape having an outer diameter equal to or less than a hollow inner diameter of the outer rotating body. 3. A cylindrical rotor having a circumferential spiral groove formed on a surface thereof is charged into the dispersion container and sealed therein.
3. The method according to claim 2, wherein the outer rotating body is rotated.
The method of dispersion described in 1. 4. The method according to claim 1, wherein the outer rotating body is rotated while heating the dispersion container.
The method of dispersion described in 1. 5. The dispersion method according to claim 1, wherein the outer rotating body is rotated while changing the number of rotations. 6. A dispersion container having a hollow cylindrical outer rotating body having a rotation axis in a horizontal direction, a viscous liquid and an additive mixed therein, hermetically sealed, and mounted on the hollow inner surface of the outer rotating body. And a rotating means for rotating the outer rotating body.