JP2009023364A - High-pressure loading pump apparatus and high-pressure dispersing apparatus using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-pressure loading pump apparatus which can maintain high sealing performance for a long period of time and has high reliability, and to provide a high-pressure dispersing apparatus using the same. <P>SOLUTION: The high-pressure loading pump apparatus is equipped with a rod 1 which performs reciprocating movement in a shaft direction, a high-pressure loading chamber 3 which loads high pressure by extruding the rod 1, a rod washing chamber 4 which is provided in a direction reverse to the direction where the rod 1 is extruded at the time of high pressure loading so as to adjoin the high-pressure loading chamber 3, a high-pressure seal 5 which carries out liquid-tight partition by sealing slurry 2 pressurized with high pressure and a washing liquid supply mechanism 7 which carries out circulation supply of the washing liquid 6 to the rod washing chamber 4 when the rod is moved from the high-pressure loading chamber side to the rod washing chamber side. Circulation supply of the washing liquid 6 to the rod washing chamber 4 is carried out and when the rod 1 is moved from a high-pressure loading chamber 3 side to a rod washing chamber 4 side, solid particles stuck to the rod 1 are removed by the washing liquid 6. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a high-pressure load pump device, and more specifically, a high-pressure load pump device used for high-pressure dispersion of a slurry containing ceramic powder or metal powder used as a solid particle as a solid particle, and the like. The present invention relates to the high-pressure dispersion apparatus used.

For example, a ceramic green sheet used when manufacturing multilayer ceramic electronic components such as multilayer ceramic capacitors and multilayer substrates uses a slurry in which solid particles having a function corresponding to each application are dispersed in a solvent. These slurries are usually produced by dispersing ceramic powder in a solvent (dispersion medium) using a dispersing device such as a bead mill, a ball mill, an attritor, a paint shaker, a sand mill, or a homogenizer.
And the ceramic green sheet is manufactured by shape | molding the slurry manufactured as mentioned above into a sheet | seat of predetermined thickness by methods, such as a doctor blade method, and making it dry.

Conventionally, using the ceramic green sheet manufactured as described above, a multilayer ceramic electronic component (here, a multilayer ceramic capacitor will be described as an example) is manufactured by the following method.
(1) First, a predetermined number of electrode-arranged sheets in which a capacitance forming internal electrode (a conductive paste containing a metal powder as a conductive component) is formed by a method such as a screen printing method are laminated on a ceramic green sheet. An outer layer ceramic green sheet having no electrode disposed on the side is laminated and pressure-bonded to form a laminate.
(2) Next, this laminated body is cut at a predetermined position and divided to form elements (unfired elements) in which one end side of each internal electrode is alternately drawn to the end face on a different side.
(3) This element is fired under predetermined conditions to sinter the ceramic to obtain a ceramic element.
(4) By applying and baking a conductive paste on both ends of this ceramic element to form external electrodes, internal electrodes alternately drawn on the end faces on different sides are formed on both ends of the ceramic element. A ceramic capacitor having a structure connected to the external electrode is obtained.

  In the above description, a case where a multilayer ceramic capacitor is manufactured has been described as an example. However, other multilayer ceramic electronic components such as a multilayer ceramic multilayer substrate are also manufactured through a process of stacking ceramic green sheets.

By the way, in recent years, various multilayer ceramic electronic components such as a multilayer ceramic capacitor are required to be downsized and have high performance in the same manner as other electronic components.
For this purpose, it is necessary to reduce the thickness of the ceramic green sheet used in the production of the multilayer ceramic electronic component. In recent years, it has become necessary to use an extremely thin ceramic green sheet having a thickness of 10 μm or less.

  Thus, when trying to produce a ceramic green sheet having a small thickness, it is necessary to use a ceramic slurry that is sufficiently dispersed as a ceramic slurry used in the production of the ceramic green sheet. As the ceramic raw material powder, it is necessary to use a fine ceramic raw material having an average particle diameter of 0.01 to 1.0 μm.

  In addition, when trying to reduce the size and thickness of a multilayer ceramic electronic component, not only a ceramic green sheet using the above-mentioned fine powder ceramic raw material is required, but also to form internal electrodes on the ceramic green sheet. The conductive paste used is also a fine powder having an average particle size of 0.01 to 1.0 μm or less as a metal powder (for example, a powder of silver, copper, nickel, palladium, etc.) as a conductive component. A conductive paste using is required.

  Therefore, in recent years, as a dispersion device for obtaining a slurry in which solid particles are sufficiently dispersed in a solvent (dispersion medium), solid particles such as ceramic powder are caused to flow into the solvent (dispersion medium) by flowing the slurry at a high pressure. Dispersing devices that disperse uniformly (hereinafter referred to as “high-pressure homogenizer”) are used, and this high-pressure homogenizer is used for producing a slurry (solid particle dispersion) in comparison with other dispersing devices. It has excellent particle dispersibility and is characterized by very little contamination from the apparatus as compared with a dispersing apparatus such as a ball mill.

  In a high-pressure homogenizer, a plunger pump or an intensifier is generally used as a high-pressure load device for applying a high pressure to the slurry. The high-pressure load device loads a high pressure of 10 to 400 MPa to the slurry. Has been.

However, when a high pressure load operation in which a high pressure is applied to the slurry by the above high pressure load device is performed continuously for a long period of time in order to disperse ceramic powder (solid particles) having a particle size of 1.0 μm or less in a solvent, Such a problem occurs.
(1) For example, in order to perform the operation at a high pressure of 10 to 400 MPa, the high-pressure load device reciprocates the rod that functions to load the slurry with a high pressure at a rate of several to several tens of times per minute. At this time, the solid particles in the slurry get caught in the gap (sliding part) between the high-pressure seal and the rod for sealing the high-pressure slurry, and the seal member that constitutes the high-pressure seal is worn or damaged. Easily leaking liquid,
(2) Especially in the case of ceramic slurry used for the production of ceramic green sheets for multilayer ceramic electronic parts such as multilayer capacitors and multilayer substrates, sealing is performed in an extremely short time due to the characteristics of the ceramic powder (solid particles) used. The member wears and breaks, causing liquid leakage.
In other words, the ceramic powder (solid particles) used in these applications is fine, so that it easily enters and accumulates between the high-pressure seal and the rod, and it is extremely hard, so it easily wears seal members made of resin, for example. The seal performance is impaired.

  In addition, when manufacturing a slurry (for example, conductive paste) containing metal powder as solid particles, if the metal powder is dispersed by a high-pressure dispersion method, the high-pressure seal and the rod are not formed due to the ductility of the metal powder. There are problems such as increasing the frictional resistance between them, reducing the rigidity of the resin seal member due to frictional heat, or causing the seal member to be greatly deformed due to frictional stress, which can easily lead to breakage. The current situation has not yet been reached.

  The present invention solves the above-mentioned problems, and aims to provide a high-pressure load pump device that can maintain high sealing performance for a long period of time and has high reliability, and a high-pressure dispersion device using the same. To do.

In order to achieve the above object, the high-pressure load pump device of the present invention (Claim 1)
A high-pressure load pump device used for applying a high pressure to a slurry containing ceramic powder and / or metal powder as solid particles used in the production of a ceramic electronic component,
An axially reciprocating rod;
A high-pressure load chamber in which a high pressure is applied to the internal slurry by pushing the rod;
A rod cleaning chamber provided adjacent to the high-pressure load chamber on the opposite side to the direction in which the rod is pushed during high-pressure load;
A high-pressure seal that partitions the high-pressure load chamber and the rod cleaning chamber in a liquid-tight manner without interfering with the operation of the rod;
A cleaning liquid supply mechanism for circulating and supplying the cleaning liquid for cleaning the rod to the rod cleaning chamber when the rod moves from the high pressure load chamber side to the rod cleaning chamber side;
When the rod moves from the high-pressure load chamber side to the rod cleaning chamber side, solid particles adhering to the rod are removed by circulating and supplying cleaning liquid to the rod cleaning chamber. It is characterized by.

A rod that reciprocates in the axial direction, a high-pressure load chamber that loads high pressure by pushing out the rod, and a rod cleaning chamber that is adjacent to the high-pressure load chamber on the opposite side to the direction in which the rod is pushed during high-pressure loading A high-pressure seal that liquid-tightly partitions the high-pressure load chamber and the rod cleaning chamber, and a cleaning liquid supply mechanism that circulates and supplies the cleaning liquid to the rod cleaning chamber when the rod moves from the high-pressure load chamber to the rod cleaning chamber. When the rod moves from the high pressure load chamber side to the rod cleaning chamber side, the cleaning liquid is circulated and supplied to the rod cleaning chamber. In the rod cleaning chamber, the solid particles attached to the rod are removed by the cleaning liquid. As a result, it is possible to suppress the intrusion of solid particles between the high-pressure seal and the rod, and to maintain necessary sealing performance for a long period of time, so that stable operation can be performed.
That is, as a method for supplying the cleaning liquid, it is desirable to supply the cleaning liquid to the rod cleaning chamber in the step of pushing the rod into the rod cleaning chamber as in the present invention.

  In the high-pressure load pump device according to the present invention (Claim 1), the high-pressure seal for sealing the high-pressure slurry is in contact with the rod from the viewpoint of reducing the amount of solid particles deposited between the rod and the rod. A lip seal having a small area, a U-shaped seal, a Bridgeman-type seal, and the like are preferable. Note that a gland packing or a block type having a large contact area with the rod is not so preferable.

  Moreover, there is no special restriction | limiting also about the material which comprises a high pressure seal, Although various things can be used, Resin materials, such as ultrahigh density polyethylene and ultrahigh molecular weight polyethylene, are illustrated as a suitable material. .

  Further, in the high pressure load pump device according to claim 2, a U-shaped seal is used as the high-pressure seal, the U-shaped seal is disposed so that an opening thereof faces the high-pressure load chamber side, and It is characterized by being supported by a backup ring disposed on the rod cleaning chamber side with respect to the U-shaped seal.

  By configuring as described above, as described in the embodiment, it is possible to perform a stable seal, which is significant.

  The high-pressure load pump device according to claim 3 is characterized in that the cleaning liquid circulated and supplied to the rod cleaning chamber is introduced in the vicinity of the high-pressure seal in the rod cleaning chamber.

  By introducing the cleaning liquid in the vicinity of the high pressure seal in the rod cleaning chamber, after moving into the rod cleaning chamber, the solid particles adhering to the rod that will be pushed back into the high pressure load chamber by operating in the opposite direction are cleaned efficiently. It becomes possible. In order to increase the cleaning efficiency, it is desirable to increase the supply amount of the cleaning liquid as much as possible.

  The high-pressure load pump device according to claim 4 is characterized in that the cleaning liquid is substantially the same solvent as the slurry solvent (dispersion medium).

  When a solvent substantially the same as the slurry solvent (dispersion medium) is used as the cleaning liquid, even when the cleaning liquid is mixed with the slurry, no foreign components are mixed into the slurry or the composition does not fluctuate. The invention can be made more effective.

  Moreover, the high-pressure dispersion device of the present invention (Claim 5) uses a high-pressure load pump device according to any one of Claims 1 to 4 to apply high pressure to a slurry containing ceramic powder and / or metal powder as solid particles. It is characterized in that ceramic powder and / or metal powder is dispersed by loading.

  By using the high-pressure load pump device according to any one of claims 1 to 4, it is possible to load high-pressure to a slurry containing ceramic powder and / or metal powder as solid particles stably over a long period of time. In addition, a high-pressure dispersion apparatus capable of efficiently dispersing the metal powder in the slurry can be provided.

  The high-pressure dispersion apparatus according to claim 6 is characterized in that the ceramic powder and / or the metal powder has an average particle diameter of 0.01 to 1.0 μm.

  Hereinafter, the features of the present invention will be described in detail with reference to embodiments of the present invention.

[Embodiment 1]
FIG. 1 is a cross-sectional view showing a configuration of a high-pressure load pump device according to an embodiment (Embodiment 1) of the invention of claim 1 of the present application, and FIG. 2 is a cross-sectional view showing an enlarged main portion.
The high-pressure load pump device according to the first embodiment includes a rod 1 that reciprocates in the axial direction, and a high-pressure load that includes a slurry outflow / inflow port 9 in which high pressure is loaded on the internal slurry 2 when the rod 1 is pushed out. Washing rod provided adjacent to the high-pressure load chamber 3 in the load chamber 3 and in the direction (arrow B direction) opposite to the direction in which the rod 1 is pushed out when a high pressure is applied (direction of arrow A) The chamber 4, the high-pressure load chamber 3, and the rod cleaning chamber 4 are liquid-tightly partitioned without interfering with the operation of the rod 1, the bup-up ring 8 that holds the high-pressure seal 5, and the rod 1 is cleaned. The cleaning fluid supply mechanism 7 for circulating and supplying the cleaning fluid 6 to the rod cleaning chamber 4 is provided. The high-pressure load chamber 3 and the rod cleaning chamber 4 are divided into two regions by the high-pressure seal 5 inside the main body housing 10. Split It is formed by.

  The cleaning liquid supply mechanism 7 also circulates and supplies the cleaning liquid, an inlet port 11 for supplying the cleaning liquid 6 to the rod cleaning chamber 4, an outlet port 12 for discharging the cleaning liquid used for cleaning from the rod cleaning chamber 4. A circulation line 13 for circulation and a circulation pump (a tubing pump in the first embodiment) 14 for circulating and supplying the cleaning liquid are formed.

  Further, the rod 1 is configured to reciprocate in the A direction and the B direction. When the rod 1 is moved in the direction of arrow A, the distal end side 1a of the rod 1 is pushed out to the high pressure load chamber 3, and the high pressure load When a high pressure is applied to the slurry 2 in the chamber 3, and the slurry 2 loaded with the high pressure is discharged from the slurry outflow / inflow port 9, and the rod 1 is moved in the direction of arrow B, the tip end side 1 a of the rod 1. Retreats from the high pressure load chamber 3, and the slurry 2 flows into the high pressure load chamber 3 from the slurry outflow / inflow port 9.

  In the first embodiment, a U-seal made of ultra-high density polyethylene is used as the high-pressure seal 5, and a PEEK product is used as the backup ring 8.

  In the first embodiment, the inlet port 11 for supplying the cleaning liquid 6 to the rod cleaning chamber 4 and the outlet port 12 for discharging the cleaning liquid used for cleaning from the rod cleaning chamber 4 increase the cleaning efficiency. It is provided in the vicinity of the high-pressure seal 5 and in the vicinity of the backup ring 8.

  In the high-pressure load pump device according to the first embodiment configured as described above, the rod 1 moves in the direction of the arrow A, and the slurry 2 in the high-pressure load chamber 3 is loaded with high pressure, and the slurry flows out and flows in. After discharging from the port 9, the rod 1 is moved in the direction of arrow B (that is, the slurry 2 flows into the high-pressure load chamber 3 from the slurry outflow / inflow port 9), and then the rod cleaning chamber from the inlet port 11. The slurry (solid particles) adhering to the rod is removed by supplying the cleaning liquid 6 into the nozzle 4, and the cleaning liquid used for cleaning is discharged to the outside from the outlet port 12, and again through the circulation line 13. It will be supplied to the rod cleaning chamber 4.

<High pressure load test 1>
Next, using the high-pressure load pump device of Embodiment 1 described above, the operation (loading time) until the high-pressure seal 5 is broken by continuously performing the operation of loading and dispersing the high-pressure to the slurry under the following conditions is performed. It was measured.

  In this high-pressure load test 1, as slurry, 100 parts by weight of a commercially available ceramic powder (average particle size 0.2 μm), 2 parts by weight of an anionic dispersant, 10 parts by weight of an acrylic binder, and 100 parts by weight of toluene are blended. A ceramic slurry was used.

The configuration and other conditions of the high-pressure load pump device were as follows.
(1) Volume of rod cleaning chamber 4: 3cc
(2) Supply amount of cleaning liquid to the rod cleaning chamber 4: 300cc / min
(3) Cleaning solution 6: Toluene
(4) Rod 1: Diameter 10mm, 1 stroke volume 5cc
(5) Load pressure to slurry: 100 MPa

Under the above conditions, when continuous operation was performed in which high pressure was applied to the ceramic slurry, continuous operation for 450 hours could be performed before the high-pressure seal was broken.
For comparison, when a continuous operation was performed under the same conditions using a high-pressure load pump device not provided with a rod cleaning chamber, the continuous operation time until the high-pressure seal was broken was 11 hours. From this, it can be seen that the durability of the high-pressure load pump device of the first embodiment is significantly improved as compared with the comparative device.

  In the first embodiment, since the same solvent (toluene) as the cleaning liquid used in the ceramic slurry is used as the cleaning liquid, there is no problem that the cleaning liquid is mixed with the slurry.

<High pressure load test 2>
In this high-pressure load test 2, a metal powder slurry comprising 100 parts by weight of commercially available Ni metal powder (average particle size 0.5 μm), 45 parts by weight of alphaterpineol and 100 parts by weight of toluene is used as the slurry. A continuous operation was performed under the same conditions as in the high-pressure load test 1 except for the above.
As a result, 380 hours of continuous operation could be performed before the high-pressure seal 5 was broken.
For comparison, when a continuous operation was performed under the same conditions using a high-pressure load pump device without a rod cleaning chamber, the continuous operation time until the high-pressure seal was broken was 4 hours. From this, it can be seen that the durability of the high-pressure load pump device of the first embodiment is significantly improved as compared with the comparative device.

  In addition, by using the high-pressure load pump device of the present invention for a high-pressure dispersion device for dispersing a slurry containing ceramic powder and / or metal powder as solid particles, ceramic powder and / or It is possible to provide a high-pressure dispersion apparatus capable of applying high pressure to a slurry containing metal powder as solid particles and capable of efficiently dispersing ceramic powder and / or metal powder.

  The invention of the present application is not limited to the first embodiment, and various applications and modifications are made within the scope of the invention regarding the types of ceramic powder and metal powder, or the type of solvent (dispersion medium). It is possible.

[The invention's effect]
As described above, the high-pressure load pump device according to the present invention (Claim 1) includes a rod that reciprocates in the axial direction, a high-pressure load chamber that loads high pressure by pushing the rod, and a direction in which the rod is pushed during high-pressure loading. On the opposite side, a rod cleaning chamber provided adjacent to the high pressure load chamber, a high pressure seal that liquid-tightly partitions the high pressure load chamber and the rod cleaning chamber, and a cleaning liquid supply that circulates and supplies cleaning liquid to the rod cleaning chamber Since the cleaning liquid is circulated and supplied to the rod cleaning chamber, when the rod moves from the high pressure load chamber side to the rod cleaning chamber side, the solid particles adhering to the rod are removed by the cleaning liquid. It becomes possible to remove efficiently. As a result, it is possible to suppress the intrusion of solid particles between the high-pressure seal and the rod, and to maintain necessary sealing performance for a long period of time, so that stable operation can be performed.

  As in the high-pressure load pump device according to claim 2, a U-type seal is used as the high-pressure seal, the U-type seal is disposed so that its opening faces the high-pressure load chamber side, and more than the U-type seal. When the U-shaped seal is supported by the backup ring disposed on the rod cleaning chamber side, stable sealing can be performed.

  Further, when the cleaning liquid is introduced in the vicinity of the high pressure seal in the rod cleaning chamber as in the high pressure load pump device of claim 3, it becomes possible to more efficiently clean the solid particles attached to the rod, The invention can be made more effective.

  Further, as in the high-pressure load pump device according to claim 4, when a solvent substantially the same as the slurry solvent (dispersion medium) is used as the cleaning liquid, even when the cleaning liquid is mixed with the slurry, different components are mixed into the slurry. In other words, the present invention can be made more effective without any composition fluctuations.

  In addition, the high-pressure dispersing device according to the present invention (Claim 5) applies high pressure to the slurry containing ceramic powder and / or metal powder as solid particles. Therefore, it is possible to stably apply a high pressure to a slurry containing ceramic powder and / or metal powder as solid particles over a long period of time, and to put ceramic powder and / or metal powder in the slurry. It is possible to provide a high-pressure dispersion device that can be dispersed efficiently.

  Moreover, the high-pressure dispersion apparatus of the present invention is particularly significant when dispersing ceramic powder and / or metal powder having an average particle diameter of 0.01 to 1.0 μm as in claim 6.

It is sectional drawing which shows the structure of the high pressure load pump apparatus concerning embodiment (Embodiment 1) of this invention. It is sectional drawing which expands and shows the principal part of the high-pressure load pump apparatus of Embodiment 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rod 1a Rod tip 2 Slurry 3 High pressure load chamber 4 Rod cleaning chamber 5 High pressure seal 6 Cleaning liquid 7 Cleaning liquid supply mechanism 8 Bup-up ring 9 Slurry outflow / inflow port 10 Main body housing 11 Inlet port 12 Outlet port 13 Circulation line 14 Circulation Pump (tubing pump)
A Arrow indicating the direction in which the rod is pushed out under high pressure load B Arrow showing the direction opposite to the direction in which the rod is pushed out under high pressure load

Claims (6)

A high-pressure load pump device used for applying a high pressure to a slurry containing ceramic powder and / or metal powder as solid particles used in the production of a ceramic electronic component,
An axially reciprocating rod;
A high-pressure load chamber in which a high pressure is applied to the internal slurry by pushing the rod;
A rod cleaning chamber provided adjacent to the high-pressure load chamber on the opposite side to the direction in which the rod is pushed during high-pressure load;
A high-pressure seal that partitions the high-pressure load chamber and the rod cleaning chamber in a liquid-tight manner without interfering with the operation of the rod;
A cleaning liquid supply mechanism for circulating and supplying the cleaning liquid for cleaning the rod to the rod cleaning chamber when the rod moves from the high pressure load chamber side to the rod cleaning chamber side;
When the rod moves from the high-pressure load chamber side to the rod cleaning chamber side, solid particles adhering to the rod are removed by circulating and supplying cleaning liquid to the rod cleaning chamber. High-pressure load pump device characterized by. A U-shaped seal is used as the high-pressure seal, and the U-shaped seal is disposed so that an opening thereof faces the high-pressure load chamber side, and closer to the rod cleaning chamber side than the U-shaped seal. The high-pressure load pump device according to claim 1, wherein the high-pressure load pump device is supported by a backup ring provided.   The high-pressure load pump device according to claim 1 or 2, wherein the cleaning liquid circulated and supplied to the rod cleaning chamber is introduced in the vicinity of the high-pressure seal in the rod cleaning chamber.   The high-pressure load pump device according to any one of claims 1 to 3, wherein the cleaning liquid is substantially the same solvent as the slurry solvent (dispersion medium).   Dispersing ceramic powder and / or metal powder by applying high pressure to a slurry containing ceramic powder and / or metal powder as solid particles using the high-pressure load pump device according to claim 1. A high-pressure dispersion apparatus characterized in that   6. The high-pressure dispersion apparatus according to claim 5, wherein the ceramic powder and / or the metal powder has an average particle diameter of 0.01 to 1.0 [mu] m.

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