JPH105563A - Wet fine grain dispersing and crushing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wet fine grain dispersing and crushing machine delivering a superfine grain diameter product continuously without increasing the number of treatments. SOLUTION: This wet superfine grain dispersing and crushing machine consists of a dispersing and crushing vessel 11 and a separation mechanism 12 connected to the opening of the vessel on the outlet side (on the right in the figure). A liq. mixture of the processing soln. and dispersant introduced into the vessel 11 from its inlet 15 is dispersed by plural agitating disks 14, crushed and agitated. The separation mechanism 12 consists of a separation cylinder 18, bearing holding cylinder 19, covering 21 and motor 22. An annular plate 24 is fixed within the central opening of the partition wall 27a of the separation cylinder 18 on the crushing vessel side. A rotary disk 25 having an outer diameter larger than the inner diameter of the annular plate 24 is opposed to the annular plate 24 with a 0.07mm clearance in between. A medium having 0.3mm initial diameter is charged into the vessel 11 and used until worn to 0.2mm diameter. A product (suspension) consisting of the dispersant having <=0.7μm grain diameter is obtained in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wet type fine particle dispersing and crushing machine for uniformly dispersing a suspension of fine particles such as pigments, magnetic agents, ceramics and organic substances and a resin solvent.

[0002]

2. Description of the Related Art Conventionally, there is a continuous dispersing apparatus which has a rotary stirrer in a fixed container, mixes fine particles in a liquid and uniformly disperses the liquid to form a suspension.

FIG. 3 is a diagram showing a configuration of a suspension extraction section of such a continuous dispersion apparatus (wet-type fine particle dispersion / pulverization apparatus). The continuous dispersion apparatus shown in FIG.
Inside, a rotating stirrer, not particularly shown, is provided, and contains a grinding aid generally called a medium or a medium made of beads such as glass, ceramics, metal, natural stone, and plastics, and contains a resin solvent and the like. The processing solution and the dispersant such as a chemically synthesized pigment, a magnetic agent, and an organic substance are fed and stirred at a high speed, so that the dispersant is pulverized into fine particles, mixed with the processing solution, uniformly dispersed, and suspended. Cloudy.

At the outlet of the fixed container 1, a separation annular plate 2 is fixedly mounted. In the ring, a rotating disk 4 fixed to the tip of a drive shaft 3 has an outer peripheral surface and the inside of the separation annular plate 2. It is rotatably arranged while keeping a slight gap A between itself and the peripheral surface uniform over the entire circumference. With this small gap A, the outflow of the grinding aid is stopped, and only the suspension is continuously extracted.
The extracted suspension is commercialized as a certain kind of emulsion or coating agent.

The rotary disk 4 is mounted on the same shaft as the drive shaft of the rotary stirring member in the fixed container 1, and FIG.
Some are mounted on separate rotating shafts as in (a),
The principle of extracting the suspension is the same in any structure.

[0006] In recent years, with the advancement of technology in the field of using such a suspension, the demand for the size of the dispersant in the suspension has been changing year by year. For example, in a conventional general-purpose suspension, the particle size of the dispersant was about 2 μm to 3 μm, but at present, the fine particle “3 μm to 0.7 μm” and the ultrafine particle “0.
7 μm or less ”, the area of micronization of the dispersant has been almost divided according to the field of use of the suspension.

By the way, the dispersant in such a suspension is not always fine from the beginning, but is trapped between the media in the above-mentioned fixed container and pulverized by stirring to be fine. The finer the particles of the medium used for this, the smaller the particle size of the product (suspension) (particle size of the dispersant). In addition, the size is reduced to some extent according to the number of processes (from injection into the fixed container to extraction from the outlet).

FIG. 4 is a characteristic diagram showing the correlation between the particle size of the product and the size of the medium contained in the fixed stirring container. This figure shows a characteristic curve for each particle diameter of the medium, in which the horizontal axis indicates the number of treatments and the vertical axis indicates the particle diameter of the product. The above characteristic curve is 1.0 to 1.5 mmφ, 0.8 to
1.25mmφ, 0.5-0.8mmφ, 0.42-
The graph shows the particle size reduction characteristics when a medium having a particle diameter of 0.6 mmφ and 0.35 to 0.59 mmφ is used.

For example, the relationship between the medium particle size and the product particle size when the number of times of processing is one is roughly, but roughly:
In order to obtain a product having a particle size of 0 μmφ, 1.0 to 1.5 mm
It is preferable to use a medium having a diameter of 0.8 to 1.25 mmφ to obtain a product having a particle diameter of 1.6 μmφ.
A medium of 0.5 to 0.8 mmφ to a product particle size of 2 μmφ,
Medium of 0.42 to 0.6 mmφ for product particle size of 1.0 μmφ, and 0.35 to 0.5 for product particle size of 0.9 μmφ
It turns out that it is better to use each medium of 9 mmφ.

When the number of times of processing is set to two, using the same medium, 1.5 μmφ, 1.2 μmφ,
It can be seen that products having particle diameters of 0.85 μmφ, 0.75 μmφ and 0.68 μmφ can be obtained. In any case, it is found that the product particle diameter converges to a constant value from the time when the number of treatments exceeds four, and that the miniaturization does not proceed. Therefore, the product particle sizes 0.91 μmφ, 0.77 μmφ, 0.57
μmφ, 0.52 μmφ and 0.44 μmφ can be seen as indicating the minimum product particle size corresponding to each of the above media.

From the above, it is assumed that a medium of 0.5 mmφ is used and the number of times of processing is two (three or more times have a problem in terms of a reduction in processing efficiency and an increase in cost) (see the bottom of FIG. 4). It can be seen that a product particle size of 0.7 μmφ can be obtained. The product particle size of 0.7 μmφ belongs to the region of ultrafine particles.

[0012]

Since the above-mentioned medium is worn, it must be replaced when the medium has been worn to some extent. If this replacement is neglected, there occurs a problem that the medium forms a nodule so as to close the gap at the outlet of the apparatus (see the gap A in FIG. 3) and hinders the extraction of the suspension. 0.7μmφ, which is the area of the ultrafine particles, which has been demanded in recent years
In order to obtain a product having a particle size of 0.5 mm, a medium having a diameter of 0.5 mm is usually supplied, and when the medium is worn down to 0.3 mm, the medium is replaced with a new medium having a diameter of 0.5 mm.

On the other hand, it has been empirically found that the gap A at the outlet of the apparatus is preferably not more than 1/3 of the medium particle size in order to efficiently separate the medium during the suspension extraction. Therefore, as described above, a medium having a diameter of 0.5 mm
When used until the media is worn down, the gap A at the outlet of the apparatus shown in FIG.
It is configured to form a gap of 1/3 of 0.3 mmφ, ie, 0.1 mm, corresponding to φ.

However, at present, in order to meet the demands for miniaturization and power saving of various OA devices, the particle size of products is further increased due to ink ribbons, filters, special papers and the like incorporated or used in these OA devices. There is a demand for miniaturization. As described above (see FIG. 4), the particle size of the medium must be reduced in order to efficiently reduce the product particle size. For example, a medium of 0.3 mmφ finer than the above-mentioned 0.5 mmφ is initially supplied, and when this medium is worn down to 0.2 mmφ, it must be replaced with a new medium. Then, the gap A at the apparatus outlet corresponds to 0.2 mmφ of the worn medium particle diameter immediately before replacement,
It must be configured to form a gap of 1/3, that is, 0.07 mm.

However, according to the current technology, no matter how precisely the separation annular plate 2 and the rotary disk 4 are formed, a certain degree of variation occurs in the mounting of the rotary disk 4 to the drive shaft 3. Cannot be avoided, and the eccentricity cannot be completely removed from the rotation of the drive shaft 3. Therefore, it is extremely difficult to rotate the rotating disk 4 while maintaining a gap of 0.07 mm from the inner peripheral surface of the separation annular plate 2. There was no way to cope with the problem other than increasing the number of times of processing using a relatively large medium. However, this causes a problem that not only the processing efficiency is reduced but also the processing cost is significantly increased, and the dissatisfaction is large, and some improvement has been desired.

It is an object of the present invention to provide a wet-type fine-particle dispersing and crushing machine for extracting a product having an ultra-fine particle size without lowering the processing efficiency and increasing the cost.

[0017]

The construction of the wet type fine particle dispersion and crusher according to the present invention will be described below. The wet-type fine particle dispersing and crushing machine of the present invention contains the treatment liquid, the dispersant, and the medium in a fixed container having a rotary stirrer, and crushes the dispersant while mixing and uniformly dispersing the dispersant. A wet-type fine particle dispersing and crushing machine for continuously extracting a suspension comprising the finely divided dispersant, and an annular plate fixed to an outlet of the fixed container, and having an inner diameter larger than the inner diameter of the annular plate. A rotating disk having an outer diameter and rotating with a predetermined gap between the rotating disk and the outer surface of the annular plate.

The predetermined gap is, for example, not more than 0.1 mm (millimeter) as described in claim 2, and the rotating disk is formed of a low expansion metal material, for example, as described in claim 3. It is configured to be driven to rotate by a shaft.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic side cross-sectional view of a horizontal wet ultrafine particle dispersion crusher according to an embodiment, and FIG. 2 is an enlarged view of a suspension extraction section as a main part thereof. In FIG. 1 and FIG.
Is composed of a dispersion and crushing vessel 11 fixed to a base (not shown) and a separation mechanism 12.

The dispersion and crushing vessel 11 has a plurality of agitating disks 14 mounted on a drive shaft 13 therein. One side (upper side in the figure) of the body wall near the bottom (left side in the figure) is provided with a processing liquid. And a dispensing agent. The drive shaft 13 is connected to a drive motor 16, and the drive motor 16 rotates the plurality of stirring disks 14 in a predetermined rotation direction via the drive shaft 13. A separation mechanism 12 is connected to an end opening on the extraction port side (right side in the figure) of the dispersion and crushing container 11.

The separating mechanism 12 includes a separating tube 18, a bearing holding tube 19, a covering 21, and a motor 22 for driving a rotating disk. The bearing holding cylinder 19 has a bolt 23 attached to the separation cylinder 18.
The cover 21 is fastened to the bearing holding cylinder 19 with a bolt 28.

The separation tube 18 is provided with a partition wall 27 on the dispersion / pulverization container side.
a large opening is formed at the center of the partition wall 27a, and an appropriate cavity 30 is formed between the partition wall 27a and the partition wall 27b on the motor side. A discharge cylinder 29 is provided on one side (the upper side in the figure) of the body wall. This separation tube 18
An appropriate number of bolt insertion holes are formed in a flange 31 extending outwardly from the partition wall 27a. Bolts 32 inserted into these bolt insertion holes are fastened to screw holes provided in the flange 33 of the dispersion and crushing vessel 11, so that the separation mechanism 12 is attached to the opening end of the dispersion and crushing vessel 11.
Are continuously installed.

The inside of the above-mentioned separation cylinder 18 has a partition wall 27a.
The annular plate 24 is fixedly disposed inside the opening (see also FIG. 2). Further, a rotating disk 25 is arranged close to the annular plate 24. The rotating disk 25 is formed to have an outer diameter larger than the inner diameter of the annular plate 24, and has a predetermined gap B between the inner surface of the annular plate 24 (the outer surface when viewed from the dispersion and crushing container side). Be placed. In this embodiment, the gap B is set to 0.07 mm. The rotating disk 25 is fixed to one end of a rotating shaft 26 disposed through the other partition wall 27 b (see FIG. 1) of the separation cylinder 18, the partition wall of the bearing holding cylinder 19, and the outer wall of the covering 21. I have. The rotary shaft 26 is provided with a mechanical seal or a gland seal 34 at an insertion portion of the other partition wall 27 b of the separation cylinder 18, is supported by a bearing 35 at a partition wall of the bearing holding cylinder 19, and is attached to a drive shaft of the motor 22. The ends are joined. The rotating disk 25 is driven to rotate by a motor 22 via a rotating shaft 26. Further, a free partition 35 having a diameter larger than the inner diameter of the annular plate 24 is disposed on the side of the dispersion and crushing container 11 so as to face the rotating disk 25 and to be slightly separated from one partition 27a of the separation cylinder 18. Note that the free partition wall 35 may not be provided in some cases.

With the above structure, the mixed liquid of the processing liquid and the dispersant sent from the inlet 15 is supplied to the dispersion / pulverization container 11 by the rotating stirring disk 14 with the appropriate particle size. (In the present embodiment, the initial input particle size is set to 0.3 mmφ) and the mixture is dispersed and stirred, whereby the dispersant is pulverized to a predetermined particle size (0.7 μmφ or less in the present embodiment). And uniformly suspended in the processing solution.

The suspension moves in the direction of the outlet as the mixed liquid of the processing liquid and the dispersant is sequentially fed from the inlet 15, and the suspension moves to the one partition 27 a of the separation cylinder 18 and the free partition 35. The rotating disk 25 and the annular plate 25 which enter the compartment 36 formed by
After being separated from the medium by a gap B (see FIG. 2) formed therebetween, the medium is discharged into the cavity chamber 30, and then discharged from the discharge tube 29 to the outside.

The gap between the rotating disk 25 and the annular plate 25 is a gap formed by facing the plate surfaces.
This gap can be easily formed to 0.07 mmφ by finely adjusting the rotation shaft 26 in a direction parallel to the axis as shown by a double-headed arrow C in FIG. 2 using an appropriate positioning mechanism. It is. Also, the rotating shaft 2
6 is made of a low expansion metal material,
It can easily be maintained in various environmental changes.

Since the plate surface is opposed to the plate surface and the outer peripheral surface and the inner peripheral surface are not rotated while facing each other, the outer peripheral surface and the inner peripheral shape are respectively formed. Even if there is some lack of alignment, or if there is some eccentricity in the rotation of the rotating disk 25, there is no influence on the axial direction of the rotating shaft forming the gap. There is no problem in extracting the liquid.

As described above, since the gap between the rotating disk 25 and the annular plate 25 is 0.07 mmφ, the medium having an initial input particle size of 0.3 mmφ can be used until it is worn down to 0.2 mmφ. The medium having a particle size can be used in an ideal state. Since the medium having such a small particle diameter can be used, a product (suspension) having a diameter of 0.7 μmφ or less can be obtained by the same usual number of treatments as in other cases without increasing the number of treatments.

Although the present embodiment has been described as a horizontal wet-type fine particle dispersion crusher, the present invention is not limited to the horizontal type and may be applied to a vertical wet-type fine particle dispersion crusher.

[0030]

As described above, according to the present invention,
Since the gap is formed by making the annular plate and the rotating disk face to face with each other, a gap that is narrower than the limit gap that can be formed between the inner peripheral surface of the annular plate and the outer peripheral surface of the rotating disk is formed. Can be
Therefore, a medium having a smaller diameter corresponding to the narrow gap can be used, whereby a suspension composed of a dispersant having a finer particle diameter can be continuously extracted without increasing the number of treatments. .

[Brief description of the drawings]

FIG. 1 is a schematic side cross-sectional view of a horizontal wet ultrafine particle dispersion crusher according to an embodiment.

FIG. 2 is an enlarged view of a main part of the suspension extraction unit of FIG. 1;

FIG. 3 is a diagram showing a configuration of a suspension extraction unit of a conventional wet-type fine particle dispersion / pulverization device.

FIG. 4 is a characteristic diagram showing a correlation between a product particle size and a medium size.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 wet ultrafine particle dispersing and crushing machine 11 dispersing and crushing container 12 separation mechanism 13 drive shaft 14 stirring disk 15 feeding port 16 drive motor 18 separation cylinder 19 bearing holding cylinder 21 covering 22 rotating disk driving motor 23, 28, 32 bolt 24 Annular plate 25 Rotating disk 26 Rotating shaft 27a, 27b Partition wall 29 Discharge cylinder 30, 31, 33 Flange 34 Mechanical seal (ground seal) 35 Free partition wall 36 Compartment

Claims (3)

[Claims] 1. A processing solution, a dispersant and a medium are accommodated in a fixed container having a rotary stirrer, and the dispersant is pulverized, mixed and uniformly dispersed, and the processing liquid and the pulverized product are pulverized. What is claimed is: 1. A wet fine particle dispersing and crushing machine for continuously extracting a suspension comprising a dispersant, comprising: an annular plate fixed to an outlet of the fixed container; and an outer diameter larger than the inner diameter of the annular plate. A rotating disk that rotates with a predetermined gap between it and the outer surface of the annular plate. 2. The wet type fine particle dispersing and grinding machine according to claim 1, wherein the predetermined gap is 0.1 mm (millimeter) or less. 3. The wet-type fine particle dispersing and grinding machine according to claim 1, wherein the rotating disk is driven to rotate by a drive shaft made of a low expansion metal material.