JPH0426308B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing a ceramic laminate used, for example, in a multilayer capacitor or a multilayer coil, and particularly relates to a method that makes it possible to laminate thin ceramic green sheets. .

[Prior Art] For example, a conventional method for manufacturing a ceramic laminate used in manufacturing a multilayer ceramic capacitor is as follows.

A ceramic green sheet is applied to one or both sides of a support film made of synthetic resin, etc.
Only this ceramic green sheet is peeled off from the support film, and first, ceramic green sheets punched to a predetermined size to be laminated are prepared, and these are laminated and pressure-bonded.

In manufacturing a multilayer capacitor, predetermined internal electrodes are printed on the ceramic green sheet prior to the above-mentioned lamination step, and after the above-mentioned laminate is obtained, firing is performed. Furthermore, external electrodes are provided.

[Problems to be Solved by the Invention] However, in the above-described lamination method, when the thickness of the ceramic green sheet is reduced in order to achieve high capacity, the sheet strength decreases and the ceramic green sheet is damaged during handling. It may tear or stretch, making it extremely difficult to handle.

Also, for example, when holding a ceramic green sheet using a suction chuck,
Holes may occur in the ceramic green sheet, and wrinkles may occur in the ceramic green sheet.

Therefore, an object of the present invention is to provide a method for manufacturing a ceramic laminate that allows thinner ceramic green sheets to be laminated easily and stably.

[Means for Solving the Problems] The method for manufacturing a ceramic laminate of the present invention includes the following steps.

A green sheet supply belt having a support film and a ceramic green sheet sheeted on the support film is prepared, and a ceramic green sheet of the size to be laminated is placed on the outer periphery of the ceramic green sheet portion of the green sheet supply belt. A cut is formed along the ceramic green sheet, the green sheet supply strip with the cut is pressed against the adhesive surface from the ceramic green sheet side, and then the green sheet supply strip is separated from the adhesive surface to form a cut on the adhesive surface. Each step includes stacking the ceramic green sheet portions surrounded by the notches.

The term "adhesive surface" is used to include the outer surface of laminated ceramic green sheets as well as the synthetic resin film with an adhesive surface; in the latter case, the above-mentioned process By repeating this step, a laminate consisting of a plurality of ceramic green sheets can be obtained.

[Action and Effect of the Invention] In this invention, the ceramic green sheet has the following properties:
Since the ceramic green sheets are used for lamination work while being supported without being peeled off from the support film, even if the thickness of the ceramic green sheets is made considerably thinner, the ceramic green sheets can be laminated without tearing or elongating the parts to be laminated. It becomes possible to do so.
Similarly, since the ceramic green sheets to be laminated are not directly held by a suction chuck or the like, holes are not formed in the ceramic green sheets.

In addition, in conventional lamination methods, the warpage of ceramic green sheets was controlled based on temperature and humidity, but in the method of this invention, since the sheets are supported by a support film, the warpage of the sheets can be ignored. This eliminates the need for complicated temperature and humidity adjustment operations.

Furthermore, during lamination, the green sheet supply band is pressed against the adhesive surface, and the green sheet supply band is further separated from the adhesive surface to laminate the ceramic green sheet portions surrounded by the notches. , lamination and crimping can be carried out simultaneously, thus simplifying the overall process and also simplifying the equipment required for the lamination work. In addition, since the green sheet is handled in the form of a supply belt supported by a support film, it is easy to detect the position.
Therefore, it is also possible to easily position the green sheets during the lamination work.

Note that this invention can be used in general manufacturing methods for ceramic laminates such as multilayer capacitors and multilayer coils, and therefore, it is possible to apply an internal electrode paste or the like to the ceramic green sheet in advance if necessary. good.

[Description of Example] Hereinafter, a manufacturing method of an example of the present invention will be described.

First, as shown in FIG. 2, a green sheet supply belt 3 in which ceramic green sheets 2 are supported on a support film 1 is prepared. Support film 1
can be constructed using, for example, a synthetic resin film such as polypropylene, and the ceramic green sheet 2 can be supported by, for example, applying ceramic slurry to one side using a doctor blade. In the manufacturing method of this embodiment, the ceramic green sheets 2 are supported by the support film 1 until they are laminated,
That is, since the green sheet supply belt 3 is handled, the thickness of the ceramic green sheet 2 can be made considerably thinner.

Next, as shown in FIG. 1, a presser plate 4 and a cutting blade 5 are prepared which are arranged at a predetermined distance apart, and the green sheet supply belt 3 is positioned between them. The press plate 4 is configured to be movable in the vertical direction as shown by the arrow in the figure. Here, the presser plate 4 is moved downward and the cutting blade 5 is
The ceramic green sheet 2 is cut to form a cut in the ceramic green sheet 2.
This cut is formed along the outer periphery of the ceramic green sheet portion of the size to be laminated in the following process. Therefore, the planar shape of the cutting blade 5 is such that it follows the outer periphery of the ceramic green sheet portions to be laminated. Note that when forming this cut, the cutting blade 5 cuts the ceramic green sheet 2 but bites into the green sheet supply band 3 to the extent that it does not punch out the support film 1. Therefore, as shown in FIG. 3, which will be described later, the notch 6 does not reach the top surface of the support film 1, so even if the notch 6 is formed, the ceramic surrounded by the notch 6 will not reach the top surface of the support film 1. The green sheet portion 2a is still supported by the support film 1.

In addition, in FIG. 1, the presser plate 4 is configured to be movable in the vertical direction, but the presser plate 4 is fixed and the cutting blade 5 is configured to be movable in the vertical direction to form the cut 6. Alternatively, the notch 6 may be formed by making both the presser plate 4 and the cutting blade 5 movable in the vertical direction.

Next, as shown in FIG. 3, a support stand 7 and a press die 8 are prepared, which are placed facing each other at a predetermined distance. An adhesive sheet 9 having an adhesive upper surface is laid on the upper surface of the support base 7. Further, a suction port 10 is formed in the support base 7, and the suction port 10 is connected to a suction means (not shown). Then,
The adhesive sheet 9 is fixed on the support base 7 by suction using a suction means.

On the other hand, a suction port 12 is also formed in the presser mold 8, and the suction port 12 is connected to a suction means (not shown). In this embodiment, the green sheet supply belt 3 in which the notches 6 are formed is placed between the presser die 8 and the support stand 7, and the presser die 8 is moved downward as shown in FIG. supply zone 3
is pressed against the adhesive surface 9a of the adhesive sheet 9 from the ceramic green sheet 2 side. Through this pressure-welding operation, the ceramic green sheet portion 2a surrounded by the notch 6 is stuck to the upper surface of the adhesive sheet 9 by the adhesiveness of the adhesive surface 9a. Since it is attached using the adhesive surface 9a,
This adhesion is due to the ceramic green sheet portion 2a.
This is stronger than the adhesion between the support film 1 and the support film 1.

Therefore, by moving the press die 8 upward while operating the suction means connected to the suction port 10, the ceramic green sheet portion 2a is left on the upper surface of the adhesive sheet 9, as shown in FIG. The remaining green sheet supply band 3 can be separated as it is.

Next, by repeating the steps shown in FIGS. 2 to 5, a plurality of ceramic green sheet parts 2b...2d can be laminated on the ceramic green sheet part 2a, as shown in FIG. In this case, instead of the adhesive surface of the adhesive sheet 9,
The upper surfaces of the previously laminated ceramic green sheet portions 2a...2c function as adhesive surfaces. This is because the ceramic green sheets 2 contain a binder or the like, and when pressed against the lower adhesive surface by the press die 8 as shown in FIG. 4, they can be brought into close contact with each other.

As described above, by repeating the steps shown in FIGS. 1 to 6, the ceramic green sheet 2
can be sequentially stacked to a predetermined size. In this case, the ceramic green sheet portions 2a to 2d to be laminated are always supported by the support film 1 during the lamination operation. Therefore, it can be seen that even when the thickness of the ceramic green sheets 2 is made considerably thinner, the laminated ceramic green sheet portions 2a to 2d do not break or elongate.

In order to obtain a multilayer capacitor or a multilayer coil, an electrode paste serving as an internal electrode may be appropriately printed on the lower surface of the ceramic green sheet 2 in advance in the green sheet supply belt 3 shown in FIG.

Further, in the above embodiment, the adhesive sheet 9 was fixed on the support base 7 using the suction port 10 and suction means, but if double-sided adhesive tape is used, the adhesive sheet 9 can be fixed on the support base 7 without using the suction port and suction means. It can be fixed on 7.

FIG. 7 is a sectional view for explaining a modification of the above embodiment. Here, instead of the cutting blade 5 shown in FIG. 1, a cutting blade 25 is attached to the base plate 21 via a compression spring 22. Therefore, when the plate 24 moves downward and a cut is formed in the ceramic green sheet 2 by the cutting blade 25, the depth of the cut can be controlled by adjusting the elastic force of the pressing spring 23. can. Furthermore, if a suction means is disposed within the cutting blade 25, the cut ceramic green sheet portions 2a can be stored in the cutting blade 25 in a stacked state. In this case as well, an adhesive sheet 9 having an adhesive surface on the upper surface is stored in advance in the cutting blade 25, and the cut ceramic green sheet portions 2a are laminated using the adhesive surface of the adhesive sheet 9. .

FIG. 8 is a sectional view for explaining still another embodiment of the invention. In the steps shown in FIGS. 3 to 5, the green sheet supply strip 3 is separated using the suction port 12 of the pressing die 8 and the suction means.
However, in the configuration shown in FIG. 8, the remaining green sheet supply band 3 is separated from the ceramic green sheet portion 2a laminated on the adhesive surface by utilizing the elasticity of the support film 1. That is,
Rollers 31 and 32 are arranged above both sides of the support stand 7, and the green sheet supply belt 3 in which the notches 6 are formed is stretched over the rollers 31 and 32.
The press die 38 is moved toward the support base 7 from above. In this case, the press die 38 presses the ceramic green sheet portion 2a surrounded by the cut 6 against the adhesive sheet 9 against the tension of the support film 1. Therefore, if the press die 38 is moved upward after pressing, the remaining green sheet supply belt 3 including the support film 1 will be returned to its original state due to the tension of the support film 1, that is, the rollers 31 and 32 will not loosen. The ceramic green sheet portion 2a tends to return to its original state and is thereby separated from the ceramic green sheet portion 2a.

In addition, in each of the above-mentioned embodiments, the press die 8,
38 may be constructed of a rigid body or of a somewhat elastic material.

[Brief explanation of drawings]

Figures 1 to 6 are diagrams for explaining one embodiment of the present invention, with Figure 1 being a sectional view showing the step of forming a cut, and Figure 2 being a sectional view showing a green sheet supply band. , FIGS. 3 to 5 are cross-sectional views showing the process of press-contacting the green sheet supply strip with notches to the adhesive surface, and FIG. 6 is a cross-sectional view showing a state in which a plurality of ceramic green sheet parts are laminated. be. FIG. 7 is a sectional view for explaining another embodiment of the invention, and FIG. 8 is a sectional view for explaining still another embodiment of the invention. In the figure, 1 is a support film, 2 is a ceramic green sheet, 2a...2b is a ceramic green sheet part, 3 is a green sheet supply belt, 6
indicates the depth of cut.

Claims (1)

[Claims] A green sheet supply belt consisting of a support film and a ceramic green sheet supported by the support film is prepared, and ceramic green sheets of a size to be laminated are placed on the ceramic green sheets of the green sheet supply belt. A notch is formed along the outer periphery of the sheet portion, the green sheet supply strip with the notch formed is pressed against the adhesive surface from the ceramic green sheet side, the green sheet supply strip is separated from the adhesive surface, and the green sheet supply strip with the notch formed is pressed against the adhesive surface. A method for producing a ceramic laminate comprising the steps of overlapping ceramic green sheet portions surrounded by notches.