JPH04249106A - Manufacture of ceramic monolithic body - Google Patents

Abstract

PURPOSE:To prevent a ceramic monolithic body from being deformed in its shape by applying hydrostatic pressure to ceramic green sheets via a deformable wall on the basis of the application of pressure to a liquid in a pressure vessel and pressing uniformly the ceramic green sheets throughout the direction of their faces. CONSTITUTION:Pressure is applied to a liquid 18 by a pressurizing device through a pressure port 19 provided on a pressure vessel 11 so that a deformable wall 17 covers the opening 15 of a mold 10 containing a plurality of ceramic green sheets 12. By this method, pressure is uniformly applied to the side face walls 14 of the mold 10 and to an upper punch 16, whereby a plurality of the ceramic green sheets 12 in the mold 10 are pressed. Thus, a ceramic monolithic body is produced. Consequently, a cost which is required for manufacturing a ceramic monolithic body can be reduced.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] This invention relates to a method for manufacturing a ceramic laminate, and in particular, a pressing method for obtaining a ceramic laminate included in a ceramic laminate electronic component such as a multilayer ceramic capacitor or a ceramic multilayer substrate. It is related to.

0002

2. Description of the Related Art Conventionally, a method for manufacturing a ceramic laminate, more specifically a pressing method for obtaining a ceramic laminate, typically involves a rigid pressing method as shown in FIG. 3 or a method as shown in FIG. There is a hydrostatic press method as shown below.

[0003] In the rigid press method shown in FIG. 3, a rigid mold 1 is used, and a plurality of ceramic green sheets 2 are stored in a stacked state inside the mold 1. An upper punch 4 is fitted into the opening 3 of the mold 1, and through the upper punch 4, pressure is applied toward the stacked ceramic green sheets 2 by a suitable press machine, as shown by an arrow 5. .

In the hydrostatic press method shown in FIG. 4, a pressure vessel 7 in which a liquid 6 is sealed is used. On the other hand,
A plurality of ceramic green sheets 2 constituting a ceramic laminate are placed in a stacked state in a holder (not shown) as required, and further vacuum packed in a bag 8. In this way, the plurality of ceramic green sheets 2 vacuum-packed by the bag 8 are placed in the pressure vessel 7, and then the liquid 6 is pressurized, so that the ceramic green sheets 2 are evenly distributed from the periphery as shown by the arrow 9. is pressurized.

[0005]

However, both the rigid press method and the hydrostatic press method described above include problems that must be solved.

First, in the rigid press method shown in FIG.
As shown by the arrow 5, since a plurality of ceramic green sheets 2 are pressed only by pressure directed from top to bottom, the mold 1 must be able to withstand that pressure. This may lead to In addition, if the pressing direction of the press machine and the posture of the mold 1 and upper punch 4 are not properly aligned, pressure may not be applied evenly to the stacked ceramic green sheets 2, resulting in uneven pressure. As a result of pressing, undesirable deformation may occur in the obtained ceramic laminate.

On the other hand, the hydrostatic pressing method shown in FIG. 4 can solve the problems encountered in the rigid pressing method as described above. However, vacuum-packing the ceramic green sheet 2 to be pressed using the bag 8 is complicated, and this causes a decrease in production efficiency. Furthermore, since the bag 8 is relatively soft, it may be torn during pressing. In this way, when the bag 8 is torn, the ceramic green sheet 2 inside becomes unusable.

[0008] It is therefore an object of the present invention to provide a method for manufacturing ceramic laminates comprising a pressing process that can solve both the problems encountered in rigid pressing methods and the problems encountered in isostatic pressing methods. That's true.

[0009]

[Means for Solving the Problems] In the method for manufacturing a ceramic laminate according to the present invention, a rigid pressing method and a hydrostatic pressing method are advantageously combined in order to solve the above-mentioned technical problems.

That is, in this invention, first, like the rigid press method, a plurality of ceramic green sheets are stored in a stacked state, and a bottom wall and a bottom wall extending parallel to the extending direction of the ceramic green sheets are used. A mold made of a rigid body is prepared, and has a side wall rising from the peripheral edge of the bottom wall, and an opening whose peripheral edge is defined by the side wall at a position facing the bottom wall. A plurality of ceramic green sheets are stored in a stacked state.

On the other hand, in order to apply the hydrostatic pressing method,
A pressure vessel is prepared in which one wall surface is defined by a deformable wall made of a flexible material and a liquid is sealed inside. This pressure vessel is arranged so that its deformable wall covers the opening of a mold containing a plurality of ceramic green sheets. In this state, the liquid in the pressure vessel is pressurized,
Accordingly, the plurality of ceramic green sheets within the mold are pressurized via the deformable wall.

0012

[Effects of the Invention] According to the present invention, hydrostatic pressure is applied to a plurality of ceramic green sheets housed in a mold through the deformable wall based on the pressurization of the liquid in the pressure vessel. be done. Therefore, the plurality of ceramic green sheets are evenly pressed in the surface direction, so that the obtained ceramic laminate does not undergo undesirable deformation.

[0013] Furthermore, the deformable wall not only covers the opening of the mold but also tightly adheres to the periphery of the mold due to the pressurization of the liquid, so the mold is not required to have such high mechanical strength. First, the mold can be made smaller.

[0014] Also, like the conventional hydrostatic pressing method,
Since there is no need to vacuum pack a plurality of ceramic green sheets to be pressed using a bag, any inconvenience caused by bag breakage can be avoided.

Further, according to the present invention, the plurality of ceramic green sheets to be pressurized are processed in the air outside the pressure vessel, so that they are immersed in the liquid in the pressure vessel and taken out from the liquid. Since there is no need to do this, and there is no need to bag it, a large number of ceramic laminates can be manufactured efficiently based on an in-line process. Therefore, the cost required for manufacturing the ceramic laminate can be reduced.

[0016]

[Embodiment] FIG. 1 shows a mold 10 and a pressure vessel 11, which are used to carry out an embodiment of the present invention, in a state where they are separated from each other, and FIG. A state in which the ceramic green sheets 12 are pressed is shown.

The mold 10 is made of a rigid body and includes a bottom wall 13 extending parallel to the extending direction of the ceramic green sheet 12 and a side wall 14 rising from the peripheral edge of the bottom wall 13. Furthermore, the mold 10 has an opening 15 at a position facing the bottom wall 13, the peripheral edge of which is defined by the side wall 14. This opening 15 has an upper punch 1
6 may be fitted. Note that the upper punch 16 does not necessarily need to be used.

Inside the mold 10, a plurality of ceramic green sheets 12 to form a ceramic laminate are placed.
are stored in a stacked state, and the upper punch 16 is placed on top of it.
is placed.

On the other hand, the pressure vessel 11 is defined by a deformable wall 17 having one wall surface made of a flexible material. The flexible material constituting this deformable wall 17 is as follows:
Preferably, an elastic material such as rubber is used. A liquid 18 is sealed inside the pressure vessel 11 .

As shown in FIG. 2, the pressure vessel 11 is arranged so that the deformable wall 17 covers the opening 15 of the mold 10 containing a plurality of ceramic green sheets 12. In this state, pressure is applied to the liquid 18 from a pressurizing device (not shown) through a pressurizing port 19 provided in the pressure vessel 11 . As a result, as shown by the arrow 20, the mold 1
Pressure is evenly applied toward the side wall 14 of the mold 10 and the upper punch 16, and the plurality of ceramic green sheets 12 in the mold 10 are pressurized. In this way, a ceramic laminate is manufactured.

As can be seen from the pressurized state shown in FIG. 2, the adhesion to the mold 10 and the like is improved when the deformable wall 17 is allowed to loosen appropriately in its natural state. be able to. In addition, the mold 10 and the upper punch 1
It is better to chamfer the corners of 6 to make the deformable wall 1
7 can be used for many times.

As mentioned above, after the pressure on the ceramic green sheet 12 is finished, the pressure on the liquid 18 is released, the pressure vessel 11 is separated from the mold 10, and then another plurality of ceramic sheets are A similar pressurizing process is performed on the mold containing the green sheet.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a mold 10 and a pressure vessel 11, which are used to carry out an embodiment of the present invention, in a state where they are separated from each other.

FIG. 2 shows a plurality of ceramic green sheets 1 in a mold 10 using the mold 10 and pressure vessel 11 shown in FIG.
FIG. 2 is a cross-sectional view showing a state in which a pressurizing process is being performed on No. 2.

FIG. 3 is a cross-sectional view showing a state in which a conventional rigid press method is being carried out.

FIG. 4 is a cross-sectional view showing a state in which a conventional hydrostatic pressing method is being carried out.

[Explanation of symbols]

10 Mold 11 Pressure vessel 12 Ceramic green sheet 13 Bottom wall 14 Side wall 15 Opening 17 Deformable wall 18 Liquid 19 Pressure port 20 Arrow indicating the direction of pressure application

Claims (1)

[Claims] 1. A device for storing a plurality of ceramic green sheets in a stacked state, comprising a bottom wall extending parallel to the extending direction of the ceramic green sheets and a side wall rising from the peripheral edge of the bottom wall. A mold made of a rigid body having an opening whose peripheral edge is defined by the side wall at a position facing the bottom wall is prepared, and a plurality of ceramic green sheets are stacked in the mold. A pressure vessel is prepared, one wall of which is defined by a deformable wall made of a flexible material, and a liquid is sealed inside, and the opening of the mold containing the plurality of ceramic green sheets is The pressure vessel is arranged so that the deformable wall covers the liquid, and the liquid in the pressure vessel is pressurized to apply the plurality of ceramic green sheets in the mold through the deformable wall. A method for manufacturing a ceramic laminate, comprising pressing steps.