JPH106289A - Ceramic green sheet cutting/laminating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate of ceramic green sheets which has high laminating accuracy and is unlikely to exfoliate by preventing elongation of the green sheet as under-layer when the sheets are subjected to pressure attachment while they are being piled up. SOLUTION: A cutting head 11 is equipped with cutter blades 12, 12 on both sides of a suction head 13 in such a way as capable of elevating and sinking, and using this head 11 each ceramic green sheet 27 is sucked fast by the suction surface of the suction head 13 before the sheet 27 is cut. The sheet 27 in the fixed condition is cut by the cutter blades 12, 12. When the cut sheets 21 are laminated on a stage 30, a pressure as small as practicable is applied to sheets 21 as they are being piled up one by one, and after the last sheet 21 is laid, a further strong pressure is applied to the whole laminate of sheets 21 so that a provisional attachment by pressure is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to cutting ceramic green sheets when manufacturing electronic parts such as multilayer ceramic capacitors and multilayer ceramic inductors by laminating ceramic green sheets partially having electrode patterns. , Laminating and crimping methods.

[0002]

2. Description of the Related Art In a multilayer ceramic capacitor, which is the most typical example of a multilayer electronic component, a large number of dielectric ceramic layers having internal electrodes are stacked, and the internal electrodes are alternately drawn to the end faces of the multilayer body. External electrodes are formed on the end faces of the laminate from which these internal electrodes are drawn.

[0003] Such a multilayer ceramic capacitor includes:
For example, it has a layer structure as shown in FIG. That is, the dielectric layers 51, 51,.
Are stacked in the order shown in FIG. 11, and a plurality of dielectric layers 57 and 58 on which no internal electrodes are formed are stacked on both sides. And the internal electrode 5 of such a laminate is
External electrodes (not shown) are formed on the exposed end surfaces of the electrodes 5 and 56.

Such a multilayer ceramic electronic component is not usually manufactured individually as shown in FIG. 11, but is actually manufactured by the following manufacturing method. That is, first, a fine ceramic powder and an organic binder are kneaded to prepare a slurry, which is thinly spread on a carrier film made of a polyethylene terephthalate film or the like by a doctor blade method, and dried to produce a ceramic green sheet. Next, while the ceramic green sheet is placed on the support film, a conductive paste is printed on one surface of the support film by a screen printing method and dried. Thereafter, the sheet is cut into a desired size by a cutting head and is separated from the support film. As a result, as shown in FIG. 12, ceramic green sheets 1a and 1b in which a plurality of sets of internal electrode patterns 2a and 2b are arranged vertically and horizontally are obtained.

Next, as shown in FIG. 12, a plurality of ceramic green sheets 1a and 1b having the internal electrode patterns 2a and 2b are laminated, and some ceramic green sheets 1a and 1b having no internal electrode patterns 2a and 2b are stacked. The ceramic green sheets 1 and 1 are stacked one on top of the other, and these are further crimped,
Make a laminate. Here, the ceramic green sheets 1a and 1b are alternately stacked such that the internal electrode patterns 2a and 2b are shifted by a half length in the longitudinal direction. Thereafter, the laminate is cut into a desired size to produce a laminated green chip, and the green chip is fired.
The chip-shaped laminate thus obtained is of a cubic shape having internal electrodes alternately exposed at both end faces. Next, a conductive paste is applied to both ends of the fired laminate, and baked to form electrode terminals at both ends,
The multilayer ceramic capacitor is completed.

Here, in the step of laminating and compressing the ceramic green sheets 1, first, before the ceramic green sheets 1 are fully compressed, displacement of the ceramic green sheets 1 caused during conveyance of the laminate is prevented. In order to stack the ceramic green sheets 1 with high accuracy, the ceramic green sheets 1 are temporarily stacked and then pressurized to temporarily press them. For example, a pressing plate is arranged on the lamination stage, and the pressing plate is raised and lowered by hydraulic pressure or the like, and the stacked ceramic green sheets 1 are sequentially stacked and pressed, and the ceramic green sheets 1 are stacked and temporarily pressed at the same time.

[0007] The press plate and the lamination stage are each provided with a heater, whereby the plate surfaces are heated to a temperature of, for example, about 70 to 80 ° C during lamination and temporary compression. When the ceramic green sheets are heated, the flexibility increases and the adhesiveness also improves, so that the laminated ceramic green sheets are securely adhered. The laminated body that has been provisionally press-bonded while being stacked in this way is fully press-bonded with a higher pressure using a pressing mold or the like.

[0008]

When the ceramic green sheets are laminated and temporarily compressed by the above-described conventional laminating method and apparatus, the lower ceramic green sheet is repeatedly pressurized while being heated. Therefore, FIG.
As shown in FIG. 10, the lower ceramic green sheet 1 greatly differs between the central portion and the peripheral portion in the rate of extension, as shown in FIG. The pattern shifts, so-called stacking shift occurs. Generally, in the laminate of FIG. 10, the outer internal electrode pattern 2 a printed on the lower ceramic green sheet 1 is shifted outward from the ideal laminate of FIG. 9.

When such a stacking shift occurs, the shift cannot be confirmed from the appearance. Then, when this laminate is cut at regular intervals at a predetermined size, the internal electrode patterns 1a and 1b in the individually cut chips are not located at the center of the chip. 1b may be exposed on the side of the chip. Even if the internal electrode patterns 1a and 1b are not exposed on the side surfaces of the chips, they are too close to one of the chips and close to the external electrodes on the other side. However, there has been a problem that the reliability of the product deteriorates.

Further, in such a laminated body in which only the lower layer is stretched and laminated, a difference occurs in the adhesive strength between the layers of the ceramic green sheet 1, and after lamination, a part of the ceramic green sheet 1 is peeled off or burrs are formed. There is also a problem that it is easy to occur. Further, in the conventional method for cutting and laminating ceramic green sheets, when the ceramic green sheets are cut by a cutting head, the ceramic green sheets may be partially peeled off from the carrier film and may be deformed. As a result, wrinkles and partial elongation occur in the cut ceramic green sheet, which may cause the same lamination displacement as described above.
In view of the above-mentioned problems of the prior art, the present invention prevents the lower ceramic green sheet from being stretched when the ceramic green sheets are pressed together while being laminated, has a high lamination accuracy, and is capable of preventing lamination of the laminated ceramic green sheets. An object of the present invention is to provide a method for cutting and laminating a ceramic green sheet from which a body can be obtained.

[0011]

In the present invention, in order to solve the above-mentioned problems, the ceramic green sheet 27 is cut by using the cutting head 11 in which the cutter blades 12, 12 are provided on both sides of the suction head 13 so as to be able to move up and down. First, the ceramic green sheet 27 is sucked and held by the suction surface of the suction head 13, the ceramic green sheet 27 is fixed, and the ceramic green sheet 27 is cut by the cutter blades 12 and 12 in this state. I made it. Thereby, the ceramic green sheet 27 is cut when the ceramic green sheet 27 is cut.
Prevention of deformation, etc., so that cutting can be performed accurately.

Further, in the present invention, when stacking the ceramic green sheets 21 cut on the stacking stage 30 using the cutting head 11 as described above, each time the ceramic green sheets 21 are stacked, pressure is applied with a pressure as small as possible. Last ceramic green sheet 2
After stacking No. 1, the entire ceramic green sheet 21 was pressurized with a stronger pressure, and temporarily pressed.
Thereby, the ceramic green sheet 21 of the lower layer is formed.
The variation in the extension of the ceramic green sheet 21 with the upper layer of the ceramic green sheet 21 is suppressed, and the extension of the laminated ceramic green sheet 21 becomes uniform.

In other words, the cutting and laminating method of the ceramic green sheet includes a step of cutting the ceramic green sheet 27 placed on the cutting stage 28 into a predetermined shape by the cutting head 11, and a step of applying the cut ceramic green sheet 21 to the cutting head 11. The method includes a step of transporting the ceramic green sheet 21 onto the stacking stage 30 while adsorbing and holding the same, and a step of pressing the ceramic green sheet 21 on the stacking stage 30. Are laminated.

In this case, the suction head 1 having a suction surface for sucking the ceramic green sheet 27 on the lower surface.
A cutting head 11 having cutter blades 12, 12 provided on both sides of the cutting head 3 so as to be able to move up and down is used.
The ceramic green sheet 27 is cut by the cutter blades 12 while holding and holding the sheet.

Thus, the ceramic green sheet 2
7 is cut in a state in which the cut portion is fixed in advance by the suction head 13, so that wrinkles and deformation do not occur, and the cut 7 can be cut accurately. Here, vacuum suction is generally used as a means for sucking the ceramic green sheet 27. However, if the ceramic green sheet 27 and the internal electrode pattern are made of a magnetic material, magnetic suction can also be used.

Further, using the cutting head 11 as described above, the ceramic green sheets 21 stacked on the stacking stage 30 are stacked while being pressed by the suction head 13, and after the last ceramic green sheets 21 are stacked, All the ceramic green sheets 21 are pressed with a stronger pressure, and they are temporarily pressed. Thereby, the lower ceramic green sheet 21
Of the ceramic green sheet 21 of the lower layer is prevented from being extended.

The suction surface of the suction head 13 of the cutting head 11 is set at a temperature lower than the glass transition point of the ceramic green sheet 21, while the stacking surface of the stacking stage 30 is set at a temperature higher than the glass transition point. Is temporarily crimped. Thereby, the elongation of the ceramic green sheet 21 is reduced, and the deformation of the ceramic green sheet 21 can be prevented.

[0018]

Embodiments of the present invention will now be described specifically and in detail with reference to the drawings. 1 and 2 show a cutting head 11 used in the method of the present invention. This cutting head 11
Includes a cubic suction head 13 and cutter blades 12, 12 provided to slide up and down along the side and end surfaces of the head 13. The suction surface that is the lower surface of the suction head 13 has a size corresponding to the planar size of the ceramic green sheets 21 to be stacked. Air passages 15 connected to a vacuum source (not shown) are dispersedly opened in the suction surface, and the suction surface is brought into a negative pressure by sucking air from the suction surface side through the air passage 15. Ceramic green sheet 21, 2
7 can be adsorbed and held. This suction head 13
Has a built-in heater 34, whereby the suction surface of the suction head 13 is heated.

The cutter blades 12 are slid up and down along the side and end surfaces of the suction head 13 by an actuator 33 such as an air cylinder or a screw mechanism. When the cutter blades 12 slide downward, the cutting edge of the tip protrudes from the suction surface of the suction head 13 by a predetermined amount. Then, when sliding upward, the blade edges of the cutter blades 12, 12 are pulled in from the suction surface of the suction head 13. As described above, the suction surface of the suction head 13 has a plane size of the ceramic green sheets 21 to be laminated, that is, a size corresponding to a size at which the ceramic green sheets 27 are to be cut.
The cutting edges 2 and 12 are arranged along the edge of the suction surface.

On the other hand, FIG. 2 shows a lamination stage 30 for laminating the ceramic green sheets 21 cut as described above. In the lamination stage 30 shown, the region for laminating the ceramic green sheets 21 is one step lower. It is a recess. The stacking stage 30 is provided with a heater 3
7, which can heat the laminated surface. The concave portion in the region where the ceramic green sheets 21 are laminated is for maintaining the laminating position accuracy. Instead of providing such a concave portion, a positioning pin is set up in the laminating region of the laminating stage 30 to laminate the laminating position. There are also methods to ensure accuracy. In this case, when cutting the ceramic green sheet 21, a positioning hole is formed in the ceramic green sheet 21 corresponding to the positioning pin, and the positioning hole is inserted into the positioning pin for positioning.

Next, the ceramic green sheet 21 is sucked by the suction head 13 of the cutting head 11,
The ceramic green sheet 27 is cut by the cutter blade 12 and the cut ceramic green sheet 21 is cut.
The method of laminating on the lamination stage 30 will be described. First, as shown in FIG. 1, the ceramic green sheet 27 is held on a carrier film 28 made of a polyethylene terephthalate film or the like.
It is supplied on the cutting stage 26. An electrode pattern is printed on the surface of the ceramic green sheet 21 as necessary.

Here, the cutting head 11 is moved above the cutting stage 26, and the cutting head 11 is lowered from above the cutting stage 26 to the position shown in FIG. Abuts on 21. Here, air is sucked through the air passage 15, the suction surface of the suction head 13 is set to a negative pressure, and a part of the surface of the ceramic green sheet 27 is suctioned there. After that, the cutter blades 12, 12 are lowered by the actuators 33, 33, and the cutting edges thereof are cut into the ceramic green sheets 27.
Thereafter, as the cutting head 11 is raised, the ceramic green sheet 21 cut by the cutter blades 12 is adsorbed on the suction surface of the suction head 13.
While being held, it is cut off, peeled off the carrier film 28 and raised.

Thus, the ceramic green sheet 21
The cutting head 11 that has sucked and held is moved to the next stacking stage 30 side, and is positioned just above the stacking area of the same stage 30. Thereafter, the cutting head 11 is lowered, and the ceramic green sheet 21 held on the suction surface of the suction head 13 is placed on the stacking stage 30.
And pressurized. In this state, the air flow in the air passage 15 is stopped or slightly reversed. Thereby, the ceramic green sheet 2
The suction state of 1 is released, or the suction surface of the suction head 13 is in a weakly pressurized state, and the ceramic green sheet 21 is pushed away by the pressure. Also, the cutter blade 12
Is slid upward by the actuator 33,
The blade edge escapes so as not to hit the stacking stage 30.

In this operation, the pressure applied to the ceramic green sheet 21 from the suction head 13 is made as small as possible, and almost no pressure is applied to the first ceramic green sheet 21. Thereafter, when the cutting head 11 is raised, only the ceramic green sheets 21 are left stacked on the ceramic green sheets 31. Hereinafter, by repeating this cycle several times,
A desired number of cut ceramic green sheets 21 are cut and laminated. Also in this case, the pressure applied from the suction head 13 to the ceramic green sheets 21 when stacking the ceramic green sheets 21 is made as small as possible. Then, after the last ceramic green sheets 21 are stacked, the stacked body of the ceramic green sheets 21 is pressurized with a stronger pressure, and temporarily pressed.

In the laminating step, the suction surface of the suction head 13 is heated by the heater 34, and the temperature is set to a temperature lower than the glass transition point of the ceramic green sheet 21. On the other hand, the lamination surface of the lamination stage 30 is heated by the heater 37, and the temperature is set to a temperature higher than the glass transition point. For example, when the glass transition point of the glass component of the organic binder contained in the ceramic green sheet 21 is 70 ° C., the suction surface of the suction head 13 is set to 65 ° C., and the stacking surface of the stacking stage 30 is set to 75 ° C. Thereby, the elongation of the ceramic green sheet 21 is reduced, and the deformation of the ceramic green sheet 21 can be prevented.

A predetermined number of ceramic green sheets 21
Are laminated in a predetermined order, and then the laminate is sent to a pressure-bonding mold and subjected to full-pressure bonding. Thereafter, the multilayer body is cut into a single chip of a single multilayer ceramic inductor, the multilayer chip is baked, a conductive paste is applied to the end face, and baked to form external electrodes. Then, by plating or insulating coating the necessary parts, multilayer electronic components such as multilayer ceramic capacitors and multilayer ceramic inductors are manufactured.

Next, an example shown in FIGS. 3 and 4 will be described. In this example, instead of the actuator 33 for sliding the cutter blade 12 up and down, elastic force is urged so as to always push the cutter blade 12 downward. An elastic body 35 such as a spring is used. In this example, the cutter blade 12 cannot be forcibly moved up and down, but the cutter blade 12 can be slid up and down according to the reaction force applied to the cutting edge of the cutter blade 12. The elasticity of the elastic body 35 is set such that the suction surface of the suction head 13 comes into contact with the ceramic green sheet 27 and, after sucking it, is cut into the ceramic green sheet 27.

Next, the example shown in FIGS. 5 and 6 will be described.
This is an example in which a magnetic material sheet containing a magnetic material such as ferrite is adsorbed, cut, and laminated. Here, a magnetic force is used as means for adsorbing the ceramic green sheets 21 and 27 on the adsorption surface of the adsorption head 13. That is, in the example of FIG. 5 and FIG.
The ceramic green sheets 21 and 27 are adsorbed and released by supplying a current to or interrupting the current. It should be noted that also in this example, FIG.
And the cutter blade 12 as in the example shown in FIG.
And an elastic body 35 is provided.

Next, the example shown in FIGS. 7 and 8 will be described.
Examples 1 and 27 are examples in which a magnetic sheet containing a magnetic substance such as ferrite is adsorbed, cut, and laminated. Here, a magnetic force is also used as a means for attracting the ceramic green sheets 21 and 27 to the attracting surface of the attracting head 13, but the permanent magnet is not attached to the electromagnet 36 but to the attracting head 13 as in the examples of FIGS. A magnet 32 is incorporated. The permanent magnet 32 is moved up and down in the suction head 13 by an actuator 31 such as a solenoid. Accordingly, the ceramic green sheets 21 and 27 are attracted and released by vertically moving the permanent magnet 32 by the actuator 31. In addition,
Also in this example, the cutter blade 12 is slid up and down by the actuator 33 similarly to the example shown in FIGS. 1 and 2 described above.

[0030]

As described above, according to the present invention, the lower ceramic green sheet is prevented from elongating when the ceramic green sheets are laminated and pressed while being laminated, and the laminated ceramic green sheet has high lamination accuracy and is hardly peeled off. Is obtained.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing a step of sucking and holding a ceramic green sheet with a cutting head in an example of a method for cutting and laminating a ceramic green sheet according to the present invention.

FIG. 2 is a schematic cross-sectional view showing a step of laminating ceramic green sheets on a lamination stage in an example of the method for cutting and laminating ceramic green sheets.

FIG. 3 is a schematic cross-sectional view showing a step of sucking and holding a ceramic green sheet with a cutting head in another example of the method for cutting and laminating a ceramic green sheet according to the present invention.

FIG. 4 is a schematic cross-sectional view showing a step of laminating ceramic green sheets on a lamination stage in the example of the method for cutting and laminating ceramic green sheets.

FIG. 5 is a schematic cross-sectional view showing a step of sucking and holding a ceramic green sheet by a cutting head in another example of the method for cutting and laminating a ceramic green sheet according to the present invention.

FIG. 6 is a schematic cross-sectional view showing a step of laminating ceramic green sheets on a lamination stage in an example of the method for cutting and laminating ceramic green sheets.

FIG. 7 is a schematic cross-sectional view showing a step of sucking and holding a ceramic green sheet by a cutting head in another example of the method for cutting and laminating a ceramic green sheet according to the present invention.

FIG. 8 is a schematic cross-sectional view showing a step of laminating ceramic green sheets on a lamination stage in the example of the method for cutting and laminating ceramic green sheets.

FIG. 9 is a schematic diagram showing a laminated state of an ideal ceramic green sheet laminate.

FIG. 10 is a schematic diagram of an apparatus for laminating and pressing a ceramic green sheet in which the lower layer has increased elongation.

FIG. 11 is an exploded perspective view showing an example of a multilayer structure of the multilayer ceramic capacitor.

FIG. 12 is a perspective view showing an example of a lamination order of ceramic green sheets for manufacturing the multilayer ceramic capacitor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Cutting head 12 Cutter blade of cutting head 13 Suction head of cutting head 21 Ceramic green sheet 27 Ceramic green sheet 28 Cutting stage 30 Stacking stage

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masakazu Seki 6-16-20 Ueno, Taito-ku, Tokyo Inside Taiyo Denki Co., Ltd. (72) Inventor Yutaka Shimo 6-16-20 Ueno, Taito-ku, Tokyo Taiyo Denki Co., Ltd. (72) Megumi Takayanagi Inventor Taiyo Denki Co., Ltd. 6-16-20 Ueno, Taito-ku, Tokyo

Claims (5)

[Claims] A ceramic green sheet (27) placed on a cutting stage (28) is cut by a cutting head (1).
1) cutting into a predetermined shape, and cutting the cut ceramic green sheet (21) into a cutting head (1).
1) a step of transporting the ceramic green sheet (21) onto the stacking stage (30) while adsorbing and holding it, and a step of pressing the ceramic green sheet (21) on the stacking stage (30). In a ceramic green sheet cutting and laminating method for repeatedly laminating a plurality of ceramic green sheets (21), cutter blades (12) are provided on both sides of a suction head (13) having a suction surface for suctioning a ceramic green sheet (27) on a lower surface. , (12)
Using a cutting head (11) provided to be able to move up and down, the ceramic green sheet (27) is sucked and held on the suction surface of the suction head (13), and then the cutter blade (12) is sucked and held. A ceramic green sheet cutting and laminating method, wherein the ceramic green sheet (27) is cut according to (12). 2. A vacuum suction means for adsorbing the ceramic green sheet (27).
3. The method for cutting and laminating ceramic green sheets according to 1.). 3. The method according to claim 1, wherein the means for attracting the ceramic green sheet is magnetic attraction.
3. The method for cutting and laminating ceramic green sheets according to 1.). 4. A ceramic green sheet (27) placed on a cutting stage (28) is cut by a cutting head (1).
1) cutting into a predetermined shape, and cutting the cut ceramic green sheet (21) into a cutting head (1).
1) a step of transporting the ceramic green sheet (21) onto the stacking stage (30) while adsorbing and holding it, and a step of pressing the ceramic green sheet (21) on the stacking stage (30). In a ceramic green sheet cutting and laminating method for repeatedly laminating a plurality of ceramic green sheets (21), cutter blades (12) are provided on both sides of a suction head (13) having a suction surface for suctioning a ceramic green sheet (27) on a lower surface. , (12)
The ceramic green sheets (21) stacked on the laminating stage (30) are attached to the suction head (13) by using a cutting head (11) provided so as to be movable up and down.
And stacking the last ceramic green sheets (21) while applying pressure, and then applying a stronger pressure to all the ceramic green sheets (21) and temporarily compressing them to obtain a ceramic green sheet cut and laminated. Method. 5. The suction head (13) of the cutting head (11) is provided with a ceramic green sheet (2).
The ceramic green sheet (21) is temporarily pressure-bonded at a temperature lower than the glass transition point of (1) and at a temperature higher than the glass transition point on the lamination surface of the lamination stage (30). Ceramic green sheet cutting lamination method.