JP2671445B2 - Manufacturing method of multilayer ceramic electronic component - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a monolithic ceramic electronic component such as a monolithic ceramic capacitor that is widely used in electric products such as video tape recorders, liquid crystal televisions, and OA equipment. In addition, it can be widely used for manufacturing multilayer ceramic electronic components such as multilayer ceramic substrates, multilayer varistors, and multilayer piezoelectric elements.

2. Description of the Related Art In recent years, in the field of electronic components, with miniaturization of circuit boards, further miniaturization and higher performance of multilayer ceramic capacitors and the like have been desired. Here, a multilayer ceramic capacitor will be described as an example.

FIG. 6 is a view showing a part of a monolithic ceramic capacitor in a cross section. In FIG. 6, 1 is a ceramic dielectric layer, 2 is an internal electrode, and 3 is an external electrode. The internal electrodes 2 are alternately connected to two external electrodes 3.

Conventionally, a laminated ceramic capacitor has been manufactured by the following manufacturing method.

First, a predetermined electrode ink is printed on a ceramic raw sheet cut to a predetermined size, and the electrode ink is dried to form an electrode ink film. The required number of ceramic raw sheets on which the electrode ink film is formed is formed. Lamination was performed to obtain a ceramic green laminate, and this ceramic green laminate was cut into a desired shape, fired, and external electrodes were attached to complete the ceramic green laminate.

However, such a method of directly printing the electrode ink on the ceramic raw sheet is based on the solvent contained in the electrode ink when printing the electrode ink on the ceramic raw sheet (usually, in a commercially available electrode ink). Is 30% by weight
Contains a solvent such as diethylene glycol monobutyl ether to a certain extent)
Being invaded was a problem. Furthermore, as the ceramic raw sheet becomes thinner, pinholes are more likely to be generated in the ceramic raw sheet itself, so that there is a problem that a short circuit between the internal electrodes occurs.

Traditionally, several approaches have been taken to address this problem.

FIG. 7 is a diagram for explaining how electrode ink is printed on a green ceramic sheet by a screen printing method. In FIG. 7, 4 is a screen frame, 5 is a screen, 6 is electrode ink, 7 is a squeegee, 8 is a base, 9 is a base film, 10 is a ceramic green sheet, and 11 is a printed electrode. The arrow indicates the direction in which the squeegee 7 moves. As shown in FIG. 7, the required number of electrode-printed ceramic green sheets are laminated to form a ceramic green laminated body, and the ceramic green laminated body is cut into a desired shape and fired, and external electrodes are attached to complete the formation. It had been.

Conventionally, attempts have been made to reduce the thickness of the dielectric layer in an attempt to increase the capacitance of the monolithic ceramic capacitor. Here, in order to reduce the thickness of the dielectric layer,
It is necessary to thin the ceramic green sheet. However, when the ceramic green sheet becomes thin, the mechanical strength of itself decreases. Therefore, when the thickness of the ceramic green sheet is about 20 μm or less, there is a problem that the ceramic green sheet cannot be handled alone (hereinafter referred to as “Problem 1”), and there is a limit to thinning. . Furthermore, when the electrode ink is printed on the surface of the ceramic green sheet, the ceramic green sheet is swollen or dissolved by the electrode ink (or the electrode ink is soaked into the minute irregularities on the surface of the ceramic green sheet). There is also a problem (hereinafter referred to as problem 2) that the shorter the thickness, the more likely a short circuit is to occur.

Further, in the laminated ceramic capacitor, as the number of laminated layers increases, a partial thickness unevenness or a step difference occurs in the appearance of the laminated ceramic capacitor due to the internal electrodes. Next, this point will be described in more detail with reference to FIGS. 8 and 9.

FIG. 8 is a cross-sectional view of a monolithic ceramic capacitor when it is made into multiple layers. As can be seen from FIG. 8, the thickness B of the peripheral portion (the number of laminated internal electrodes 2 is small) is smaller than the thickness A of the central portion (the number of laminated internal electrodes 2 is large) of the multilayer ceramic capacitor.

FIG. 9 is a diagram for explaining a difference in thickness between a central portion and a peripheral portion with respect to the number of stacked layers. Here, the thickness of the green ceramic sheet used was 20 microns, and the thickness of the internal electrodes was 4 microns. From FIG. 9, it can be seen that when the number of laminated layers exceeds 10, the difference in thickness between the central portion and the peripheral portion exceeds 20 μm, that is, exceeds the thickness of the ceramic green sheet used.
Due to the unevenness due to this thickness unevenness (corresponding to the thickness of the electrode), uniform lamination as a monolithic ceramic capacitor cannot be performed, and problems such as delamination (delamination) and cracks (hereinafter referred to as problem 3) occur. Will occur.

Conventionally, several approaches have been taken for these problems (problem 1, problem 2, and problem 3).

First, as an approach considered for the problem 1, in Japanese Patent Laid-Open No. 62-63413, the surface of a ceramic green sheet is adhered to a base film so that the ceramic green sheet can be easily handled. A method has been proposed in which an electrode ink is printed on a substrate, and after lamination, the base film is peeled off. However, in this method, although the problem 1 can be solved to some extent, the problem 3 cannot be solved. Regarding problem 2, the solvent of the electrode ink soaked into the ceramic green sheet is covered by the base film on the opposite side of the ceramic green sheet (the side on which the electrode ink is not printed). Can no longer evaporate and remains in the ceramic green sheet. That is, the solvent of the electrode ink remains on the ceramic green sheet for a longer period of time than before, and the problem (problem 2) that the ceramic green sheet is more likely to be attacked by the electrode ink becomes larger than before.

Further, the method proposed in Japanese Patent Publication No. 59-172711 is to embed an electrode formed on a base film in a ceramic green sheet, and laminate and fire the entire base film to produce a multilayer ceramic capacitor. According to this proposal, although the problems 2 and 3 can be solved to some extent, the problem 1 remains. Further, in this proposal, in order to sinter the base film together, it is necessary to use a very thin base film having a thickness of about 1.5 to 14 microns. In addition, the amount of the base film to be fired increases in proportion to the number of layers, and delamination tends to occur. Therefore, it is necessary to make the base film thinner as the number of laminated layers increases. Further, such a thin base film is difficult to handle and has poor mechanical strength, so it cannot be said to be practical.

Another approach that has been considered for the problem 2 is to transfer electrodes. That is,
In JP-A-63-31104 and JP-A-63-32909, it is possible to prevent the adverse effect of the solvent of the electrode ink while preventing the adverse effect of the solvent of the electrode ink by thermally transferring the electrode ink instead of printing it on the surface of the ceramic green sheet. There has been proposed a method of forming the green sheet on a green sheet to increase the yield of the monolithic ceramic capacitor. However, in this method, both the ceramic green sheets and the electrodes are alternately laminated by thermal transfer. That is, for example, the number of stacked internal electrodes is
When the number of layers is 50, thermal transfer is repeated 50 times or more by stacking the ceramic green sheets, 50 times by stacking the electrodes, and at least 100 times or more in total. Also, if the ceramic green sheet has only one layer, there is a high possibility of pinholes,
In order to increase the yield, two-layer continuous transfer of a ceramic green sheet is considered. However, in this case, thermal transfer is repeated 150 times or more in total. Furthermore, the thermal history of each transferred layer is different. That is, the first thermally transferred layer is then subjected to a thermal history of nearly 150 times, while the last laminated layer is only subjected to a few subsequent thermal history. Generally, each time such a thermal history is applied, the ceramic green sheet gradually undergoes thermal deformation, so the thermal history becomes larger for the first thermal transferred layer,
The deformation is greater than that of the layers laminated towards the end.
For this reason, the raw ceramic sheet is deformed, the thickness is changed, the area of the electrodes is changed, the lamination position of the electrodes is shifted, and defects are easily generated at the time of cutting after lamination. Furthermore, the electrodes will be transferred later to the surface of the ceramic green sheet formed to have a uniform thickness, and uneven lamination will occur due to the thickness of the electrodes,
It does not solve problem 3.

Further, in JP-A-63-51616, after providing an electrode ink film on the film, the ceramic raw sheet is looked into so that the electrode ink film overlaps, and the electrode ink film is thermally transferred to the ceramic raw sheet, It has been proposed to stack and fire a plurality of this ceramic green sheets. However, in this method, the thermal transfer of the electrode ink film is required before the ceramic green sheets are laminated by the heat, and the thermal history is applied to the ceramic green sheets, resulting in poor accuracy. In addition, the electrodes are not transferred onto the dimensionally firm base film but transferred onto the ceramic green sheet having thermosetting property, and then transferred onto the ceramic green sheet.
At this time, not only the ceramic raw sheet but also the base film undergoes thermal deformation during the transfer of the electrodes, and the possibility of deteriorating the lamination accuracy increases. Therefore, in this method, it is indispensable to use a base film having excellent heat resistance (heat distortion resistance), which increases the manufacturing cost. Further, also in this proposal, the electrode is later transferred to the surface of the ceramic green sheet formed to have a uniform thickness, and the lamination unevenness due to the thickness of the electrode inevitably occurs, thereby solving the problem 3. It doesn't matter.

In JP-A-63-51617, the transfer of the electrode is
It has been proposed to heat and press the film on the ceramic green sheet with a pressing die having protrusions that match the electrode pattern to transfer the electrodes of a predetermined pattern from the electrode layer to the ceramic green sheet. However, in this case, if the protrusion is used, the thickness of the green ceramic sheet at that portion is inevitably changed. Further, as many protrusions as the number of electrodes are required, and the pressure in each protrusion inevitably varies. For this reason, the thickness or compression rate of the ceramic green sheet at the position of each electrode also varies. In addition, there is pressure distribution even in the protrusions that transfer one electrode (generally called the marginal zone, which causes uneven density of ink in letterpress printing), and the thickness of the ceramic green sheet Will change. In addition, since the ceramic green sheet itself and the base film on which the ceramic green sheet is formed are subjected to partial heat pressure before lamination, irregular deformation is likely to occur. Further, as in Japanese Patent Laid-Open No. 63-51616, the electrodes are not transferred onto the dimensionally firm base film, but are transferred onto a ceramic green sheet having a thermal softening property, and then transferred onto the ceramic green sheet. At this time, not only the ceramic green sheet but also the base film undergoes thermal deformation during thermal transfer of the electrodes, which deteriorates the stacking accuracy. Therefore, it is essential to use a base film having excellent heat resistance, which causes a problem of increasing manufacturing cost. Also in this proposal, the electrodes will be transferred later to the surface of the ceramic green sheet having a uniform film thickness.
Inevitably, stacking unevenness due to the thickness of the electrodes occurs, and the problem 3 cannot be solved.

Further, as in Japanese Patent Laid-Open No. 63-53912, there has been proposed a method of forming an internal electrode of a ceramic laminate in which an electrode ink film which is an internal electrode containing an ultraviolet curable resin is transferred and laminated on a ceramic green sheet. . However, in this method, only the carrier film side of the electrode ink is cured, and the surface side (the side not the carrier film) of the electrode ink is in an uncured or semi-cured state and has an adhesive property. Such a so-called raw dry electrode ink surface is easy to handle because dust and dirt easily adhere to it even if it is a little. Also, after printing the electrode ink, the carrier film cannot be wound up because the surface is dry. Furthermore, after transferring the electrode ink to the ceramic green sheet, the ceramic green sheet is laminated without being held by the carrier film. For this reason, when the thickness of the ceramic green sheet becomes about 20 microns or less, the mechanical strength of the ceramic green sheet itself is insufficient, and the ceramic raw sheet can no longer be handled. Therefore, there is a limit to how thin the green ceramic sheet can be made.

Further, as an approach that has been considered for the problem 2, there is one in which an electrode is formed on the base film in advance. For example, Japanese Patent Application Laid-Open No. 56-106244 is a method in which an electrode ink film is formed by printing on a base film and then a ceramic green sheet is formed on the electrode ink film by the casting method. In addition, as in Japanese Patent Publication No. 40-19975,
There is a method of obtaining an electrode-embedded ceramic green sheet by applying an electrode ink, drying it, and then continuously applying a dielectric slurry and peeling it from a support. According to this method, the problem 2 can be solved to some extent, but the problem 1 cannot be solved. That is, the electrode-embedded ceramic green sheet made by these methods is peeled from the base film and laminated, so that when the film thickness becomes thin, the mechanical strength extremely decreases. There was a problem (problem 1) that it could no longer be handled by itself. Further, there is a problem that irregularities due to the electrode ink film are likely to occur on the surface of the green electrode-embedded ceramic green sheet.

Further, as a method for manufacturing a monolithic ceramic capacitor in which electrodes are embedded in a ceramic green sheet, there is disclosed in JP-A-55-12.
There are methods proposed in Japanese Patent No. 4225 and Japanese Patent Publication No. 62-35255. However, in these manufacturing methods, dielectrics and electrodes are alternately printed and laminated on a single base film by a method such as gravure printing over a plurality of layers. Therefore, there is also a problem that the ceramic raw sheet is affected by the solvent contained in the electrode.

Further, as in Japanese Patent Publication No. Sho 60-49590, a first electrode is printed on the first ceramic green sheet, and then a paste containing ceramic powder is printed so as to cover the electrode.
It has been proposed to dry, form a first auxiliary ceramic layer and then stack a second green ceramic sheet. According to this method, the ceramic green sheets and the auxiliary ceramic layers are formed between the internal electrodes (that is, the ceramic green sheets are doubled). A similar method is proposed in Japanese Examined Patent Publication No. 62-21721. However, in any of the methods, the electrode-formed (or electrode-embedded) ceramic green sheet is laminated in a state of being separated from the base film. For this reason, when the thickness of the ceramic green sheet becomes about 20 microns or less, the mechanical strength of the ceramic green sheet itself is insufficient, and the ceramic raw sheet can no longer be handled. Therefore, there is a limit to how thin the green ceramic sheet can be made.

SUMMARY OF THE INVENTION Therefore, in the method for manufacturing a monolithic ceramic capacitor as described above, it is difficult to prevent the adverse effect of the solvent contained in the electrode ink. In addition, in the configuration of the multilayer ceramic capacitor that avoids the influence of the solvent of the electrode ink,
It was not possible to perform accurate lamination using thin ceramic green sheets of 20 microns or less. Furthermore, in order to prevent the influence of the solvent of the electrode ink, when the electrodes are formed on the ceramic raw sheet by thermal transfer, the ceramic raw sheet itself is easily deformed by heat and receives a complicated thermal history of more than one time, There was a limit to increasing the number of layers. Moreover, as the number of stacked layers increases, uneven stacking due to the internal electrodes occurs. Further, if the electrodes are simply embedded in the ceramic green sheet, it is difficult to handle when the ceramic green sheet becomes thin, and there is a limit to thinning the ceramic green sheet of 20 microns or less.

In view of the above-mentioned problems, the present invention forms a ceramic green sheet on an electrode that has been dried, so that a short circuit is unlikely to occur and the electrode can be embedded inside the ceramic green sheet. It can be flattened, and even a thin ceramic green sheet of 20 microns or less is laminated with the base film, so it can be handled while maintaining its mechanical strength. Furthermore, by including a tackifier in the ceramic green sheet, an electrode embedded ceramic green sheet The present invention provides a method for manufacturing a laminated ceramic electronic component, which can improve the transferability (or transferability) of (3) and can easily and accurately perform lamination.

Means for Solving the Problems In order to solve the problems, the method for manufacturing a multilayer ceramic electronic component of the present invention is to form an electrode on a base film, and the base film on which the electrode is formed, a tackifier. Is applied, and the ceramic slurry is dried to form an electrode-embedded ceramic green sheet on the base film. Then, the electrode-embedded ceramic green sheet is not peeled from the support. After thermocompression-bonding onto a ceramic green sheet or another electrode, only the support is peeled off, and the electrode-embedded ceramic green sheet is transferred onto the other ceramic green sheet or another electrode. It is a thing.

Effect of the Invention The present invention has the above-described structure, and by forming the ceramic green sheet on the dried electrode, the solvent contained in the electrode ink causes the ceramic green sheet to erode and swell, which causes a short circuit. Even when a multilayer ceramic capacitor having a multilayer structure is manufactured, by embedding the electrode in the ceramic green sheet, a step (unevenness) on the surface of the electrode-embedded ceramic green sheet due to the electrode can be prevented. Occurrence can be reduced. Also, without peeling the ceramic green sheet with the embedded electrodes from the support,
After thermocompression-bonding onto another ceramic green sheet or other electrode, only the support is peeled off and the electrode-embedded ceramic green sheet is transferred, so that the electrode-embedded ceramic green sheet can be handled when laminated. It will be easier and the stacking accuracy will be improved. Further, by including a tackifier in the electrode-embedded ceramic green sheet, more stable transfer can be achieved while preventing the transferability (or transferability) of the electrode-embedded ceramic green sheet from being varied during lamination. It will be possible.

EXAMPLES Hereinafter, a method for manufacturing a multilayer ceramic capacitor and a method for laminating the same according to one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 and FIG. 2 are views for explaining the state of laminating the electrode-embedded raw ceramic sheets in the first embodiment of the present invention. In FIGS. 1 and 2, 20 is a base, 21 and 21a are base films, 22 is a ceramic green laminate, 23 and 23a are electrodes, 24 is a ceramic green sheet, and 25 is an electrode-embedded ceramic green sheet. The electrode-embedded ceramic green sheet 25 includes an electrode 23 and a ceramic green sheet 24.
It is composed of 26 is a heater, 27 is a heating plate, 30 is a transferred electrode-embedded ceramic green sheet, and is composed of a transferred electrode 28 and a transferred ceramic green sheet 29. Arrows indicate the direction in which the hot platen 27 moves.

First, a description will be given with reference to FIG. First, a hot platen 27 heated by a heater 26 is placed on the side of the base film 21a on which the electrode-embedded ceramic raw sheet 25 is not formed. On the other hand, on the side of the base film 21a on which the electrode-embedded ceramic raw sheet 25 is formed, the base film 21 and the ceramic raw laminate 22 fixed on the table 20 are placed. At this time, as shown in FIG. 1, electrodes are formed on the surface of the ceramic green laminate 22.
23a or first ceramic green sheet (not shown)
May be formed in advance. Furthermore, the surface of the ceramic green laminate 22 may directly appear on the surface. Also,
The base film 21 may be omitted. Next, from the state shown in FIG. 1, the ceramic raw laminated body 22 (or the electrode 23 previously formed on the surface of the ceramic raw laminated body 22 by the heating plate 27 is used.
An electrode-embedded ceramic green sheet 25 formed on the surface of the base film 21a is thermocompression-bonded to the surface of (a surface).

Next, a description will be given with reference to FIG. This FIG.
FIG. 4 is a view after the electrode embedded ceramic raw sheet 25 shown in the figure has been transferred. That is, as shown in FIG. 2, the electrode-embedded ceramic green sheet 25 on the base film 21a is heated by the heating plate 27 so that the surface of the ceramic green laminate 22 (or the electrode 23a previously formed on the surface of the ceramic green laminate 22).
Surface), and thereby a transferred electrode-embedded ceramic green sheet 30 composed of the transferred electrode 28 and the transferred ceramic green sheet 29 is formed.

3 and 4 show a modification of the first embodiment, in which a ceramic green sheet 24a formed on the base film 21b is formed on the surface of the ceramic green laminate 22 having electrodes 23 formed thereon. A state is shown in which the electrode-embedded ceramic green sheet 25 is subjected to thermocompression bonding after being subjected to thermocompression bonding to form the transferred ceramic green sheet 24b. Here, FIG.
By repeating the steps of FIG. 2 and the steps of FIGS. 3 and 4, it is also possible to laminate over multiple layers.

Next, a more detailed description will be given. First, as the electrode ink for forming the electrodes, use a commercially available electrode ink,
It was used as an electrode ink after being diluted by adding a solvent for screen printing so as to have an appropriate viscosity (hereinafter, simply referred to as an electrode ink).

Next, how to make a dielectric slurry will be described. First, polyvinyl butyral resin (hereinafter referred to as PVB resin)
Add 9 parts by weight to a mixture of 23 parts by weight of solvent and 3 parts by weight of plasticizer, and further add tackifier (commonly called tack fire).
After thoroughly dissolving 0.5 parts by weight, 64 parts by weight of a dielectric powder mainly composed of barium titanate having a particle size of about 1 micron was added to this, and a grind meter (JIS-K -5701) was thoroughly kneaded while being evaluated to obtain a screen printing dielectric slurry (hereinafter referred to as a dielectric slurry). Further, a solvent for screen coating was changed from a solvent for screen coating to a mixed solvent for a reverse coating machine, and a dielectric slurry for a reverse coating machine (hereinafter, referred to as a dielectric slurry) in which the addition amount was increased was also prepared.

A polyethylene terephthalate film (hereinafter referred to as a PET film) having a film width of 200 mm, a film thickness of 75 μm, and a length of about 300 m was used as the base film 21a for electrode ink printing. Next, on this PET film, by the screen printing method,
The above electrode ink was continuously printed at regular intervals. Then, for drying the electrode ink of the printing paper, a far infrared belt furnace was connected next to the printing machine to evaporate the solvent in the electrode ink and use this as the electrode 23. Further, the above-mentioned dielectric slurry is double-printed on this with a solid pattern by a screen printing method as shown in FIG. 8 (the dielectric slurry is printed and dried, and then the dielectric slurry is further printed and dried. ) Printed. Here, when the film thickness of only the ceramic raw sheet 24 of the completed electrode-embedded ceramic raw sheet 25 was measured using an electronic micrometer, it was 16 microns.

Next, a method of manufacturing a multilayer ceramic capacitor using the electrode-embedded ceramic raw sheet 25 will be described. First, a ceramic green laminate 22 having a thickness of 200 μm and having no electrodes formed thereon was fixed together with the base film 21 on the table 20 shown in FIG. As shown in FIGS. 3 and 4, a necessary number of laminated ceramic raw sheets 25 with electrodes were transferred thereon. Here, the transfer is performed using a hot platen 27 from the side of the base film 21a under the conditions of a temperature of 150 ° C. and a pressure of 15 kilograms per square centimeter, and after transferring the electrode-embedded ceramic raw sheet 25, the base film 21a is peeled off. Was.

Hereinafter, this was repeated so that the electrodes were shifted alternately as shown in FIG. 7, and the electrodes were made into 51 layers. Finally, in order to prevent warpage during firing and increase mechanical strength, the ceramic raw sheet without electrodes
200 micron equivalent was transferred. After cutting the laminate thus obtained into chips of 2.4 x 1.6 mm, 1300
Calcination was carried out at ℃ for 1 hour.

Further, in order to investigate the influence of the solvent on the electrode, the electrode was directly printed on a ceramic green sheet as a conventional example (1). The electrode ink is directly applied onto a ceramic green sheet (dielectric slurry is printed, dried, and printed twice) formed on a PET film having the same composition and thickness as described above. By the screen printing method, the internal electrodes were printed and dried to obtain a ceramic green sheet having electrodes. Next, the ceramic raw sheet on which the electrodes were formed was transferred together with the PET film, the PET film was peeled off, and the electrodes were transferred and laminated so that the electrodes had 51 layers. Also, each condition was the same as that described above.

Here, the number of samples was n = 100. Next, external electrodes were formed using a usual method, and the occurrence ratio of short circuits was examined. The results are shown in Table 1 below.

As described above, if the method for manufacturing a multilayer ceramic electronic component according to the present invention is used, since the electrode ink is dried, both the occurrence rate of short-circuit and the incidence rate of delamination are reduced.
It can be seen that it is greatly improved as compared with the conventional method.

Here, the ceramic raw sheet portion of the electrode-embedded ceramic raw sheet used in the present invention is a PVB containing itself.
Due to the nature of the resin, it has transferability (or adhesiveness) due to heat. In addition, the transferability (or adhesiveness) of this electrode-embedded ceramic raw sheet due to heat varies greatly depending on the content of the PVB resin contained in the ceramic raw sheet. In other words, the higher the content of PVB resin in the ceramic green sheet, the better the transferability due to heat, but it is likely to cause delamination during sintering (because the content of ceramic powder decreases relatively). Can be considered.
So, about the ceramic powder of the particle size used in the experiment,
The results of the relationship between the transferability and the occurrence rate of delamination with respect to the amount of resin contained in the ceramic green sheet were determined, and the results of examining the electrode embedded ceramic green sheet of the present invention are shown in Table 2 below. .

From Table 2, it can be seen that if the PVB resin is about 10% to 40% by weight, the transferability is good and delamination is unlikely to occur. In particular, those with around 15% by weight have good transferability,
It can be seen that delamination is rare.

Here, when the PVB resin is reduced from 15% by weight to 10% by weight, the transferability of the electrode-embedded ceramic green sheet itself becomes weak (worse). For this reason, it was considered that delamination is likely to occur in the ceramic green laminated body formed by laminating the electrode green ceramic raw sheets without sufficient adhesion (because the incomplete adhesion remains). .

Next, a tackifier was added as in the present invention, and the transferability of the electrode-embedded ceramic green sheet was examined. By giving this ceramic green sheet adhesiveness (or tackiness), the transferability of this electrode-embedded ceramic green sheet can be further improved. A tackifier (tackfire) is added, and the delamination rate is increased. The results of the examination are shown in Table 3 below.

From Table 3, it is understood that the transferability of the electrode-embedded ceramic green sheet can be improved by adding the tackifier. That is, when the tackifier is not contained, the transferability is weak (PVB resin amount is 10% by weight) or even if the transferability is not present (PVB resin amount is 7% by weight). As a result, the delamination rate can be reduced. Further, addition of a tackifier not only improves the transferability of the electrode-embedded ceramic green sheet itself, but also improves the transferability of the electrode-embedded ceramic green sheet after being transferred. As a result, it was possible to more effectively improve the transferability. In addition, the transferability and transferability of the electrode-embedded ceramic green sheet can be improved by including a tackifier in the ceramic green sheet, and as a result, a ceramic green sheet with poor transferability (that is, a small amount of resin) can be obtained. It can be seen that transferability can be improved even when an electrode-embedded ceramic green sheet is manufactured using the same. This means that the minimum amount of resin required for transferring the electrode-embedded ceramic green sheet can be reduced. In other words, the resin contained in the ceramic green sheet can be decomposed more easily during firing, and the firing time can be reduced. Or shorten
Alternatively, the firing conditions can be made simple and stable. It is also effective to make the resin used for the ceramic green sheet mainly a tackifier.

Further, it is possible to further lower the transfer temperature of the electrode-embedded ceramic green sheet by adding a tackifier. Usually, the transfer temperature can be lowered by increasing the amount of resin contained in the electrode-embedded ceramic green sheet or increasing the amount of plasticizer. Further, by lowering the transfer temperature, it is possible to reduce the time and pressure required for transfer. In the present invention, the electrode-embedded ceramic green sheet can be transferred without increasing the resin amount (with the minimum required resin amount). As an example, Table 4 below shows the results of examining the transferability with respect to the transfer temperature of the electrode-embedded ceramic green sheet when the tackifier was added and when it was not added.

As described above, Table 4 shows the effect of the tackifier.
Furthermore, using a ceramic green sheet with embedded electrodes, which has weak transferability (PVB resin content of 10% by weight), and also examined transferability by changing the transfer temperature, the ceramic green sheet also contains a tackifier. The result is that the transfer temperature can be lowered by.

In addition, the tackifier may cause some stickiness on the surface of the electrode-embedded ceramic green sheet,
By peeling the base film (the surface of the base film that contacts the surface of the green electrode-embedded ceramic sheet),
There was no particular problem in handling.

Here, the PVB resin itself has a certain degree of tackifying property, but even if such a resin having poor transferability such as methyl cellulose or ethyl cellulose is used, it is easy to add the tackifier The transferability (and the transferability) can be improved. Further, the transferability (and transferability) can be easily improved even when a grade (type such as polymerization degree) having poor transferability (and transferability) is used depending on the resin.

Further, even if a curable resin or a polymerizable resin, after curing,
Even after the polymerization, the transferability is usually inferior to that of the thermoplastic resin, but the transferability can be easily improved by adding the tackifier.

Next, FIG. 5 is a view for explaining a method of transferring an electrode-embedded raw ceramic sheet using a heat roller in the second embodiment of the present invention. In FIG. 5, reference numeral 31 denotes a heat roller, which is set at a constant temperature by a heater 26a. Then, the electrode-embedded ceramic green sheet 25 is used as the ceramic green laminate 22 (or the ceramic green laminate 22).
Surface of electrode 23a previously formed on the surface of) and heat roller 31
When passing between, the electrode embedded ceramic green sheet 25,
The electrode-embedded ceramic green sheet 30 is transferred to the surface of the ceramic green laminate 22 and transferred. According to this method, the transfer of the electrode-embedded ceramic raw sheet can be continuously performed.

Further, although the screen printing method was used for manufacturing the ceramic green sheet in the examples, the electrode-embedded ceramic green sheet could also be manufactured by the gravure method by using the dielectric slurry. Also,
Needless to say, a commercially available coater such as a doctor blade method or a reverse method can be used in the production of the ceramic green sheet in addition to the gravure method which has been widely used in the ceramic industry or the magnetic tape industry.

In the present invention, the transfer may be performed by using heat, photoelectron beam, microwave, X-ray or the like. Also, by changing the type of PVB resin, the type and amount of the plasticizer, the storage stability, the lowering of the transfer temperature (room temperature), and the higher speed of lamination can be achieved. Further, as the tack fire (tackifier), one having viscoelasticity at room temperature, excellent adhesiveness and adherence, and maintaining cohesive force for a long time after the adhesion is preferable. Specifically, polyvinyl ether (including polyvinyl methyl ether, polyvinyl ethyl ether, isobutyl ether, etc.) system, polyisobutylene, styrene butadiene rubber (SBR), butyl rubber, chloroprene rubber,
Examples include vinyl chloride-vinyl acetate copolymer and chlorinated rubber.
It also includes polyvinyl butyral in a broad sense.

Further, the manufacturing method of the present invention can be applied not only to the monolithic ceramic capacitors described in the above embodiments but also to other monolithic ceramic electronic components such as a multi-layer ceramic substrate and a multi-layer varistor.

EFFECTS OF THE INVENTION As described above, according to the present invention, a ceramic slurry containing a tackifier is applied on an electrode formed on a base film, the ceramic slurry is dried, and an electrode is embedded on the base film. Making a ceramic green sheet, then without peeling the electrode-embedded ceramic green sheet from the support, after thermocompression bonding on another ceramic green sheet or another electrode, only peel the support, By transferring the electrode-embedded ceramic green sheet to another ceramic green sheet or another electrode, the electrode is dried, so that the adverse effect of the solvent contained in the electrode ink is minimized, and the ceramic green sheet is also used. Since it is handled together with the support, the electrode is embedded in the ceramic slurry without damage during handling. By doing so, it is possible to prevent the generation of irregularities on the surface of the electrode-embedded ceramic green sheet due to the electrode, and by adding a tackifier to the ceramic slurry, more stable transfer (and transferability) can be obtained, As a result, the transfer efficiency can be increased.

[Brief description of the drawings]

FIG. 1 and FIG. 2 are views for explaining a state of stacking an electrode-embedded ceramic green sheet according to the first embodiment of the present invention, and FIGS. 3 and 4 are modifications of the first embodiment. FIG. 5 is a diagram for explaining a method for transferring an electrode-embedded ceramic green sheet using a heat roller according to a second embodiment of the present invention, and FIG. 6 is an example of a monolithic ceramic capacitor. Fig. 7 is a diagram showing a section in section, Fig. 7 is a diagram for explaining a state in which an electrode ink is printed on a ceramic green sheet in a conventional example, and Fig. 8 is a sectional view of a monolithic ceramic capacitor in the same multi-layer structure. , 9th
The figure is also a diagram for explaining the difference in thickness between the central portion and the peripheral portion with respect to the number of stacked layers. 20 …… table, 21,21a, 21b …… base film, 22 …… ceramic green laminate, 23,23a …… electrode, 24,24a, 24b …… ceramic green sheet, 25 …… electrode embedded ceramic green sheet, 26, 26a …… Heater, 27 …… Hot plate, 28 …… Transferred electrode, 29 …… Transferred ceramic green sheet, 30 …… Transferred electrode embedded ceramic green sheet, 31 …… Heating roller.

Claims (2)

(57) [Claims] 1. A green electrode-embedded ceramic green sheet having electrodes formed on a base film, a ceramic slurry containing a tackifier applied to the base film having the electrodes formed thereon, and the slurry being dried. Make
Next, the electrode-embedded ceramic green sheet is thermocompression-bonded onto another ceramic green sheet or another electrode without peeling from the support, and then only the support is peeled off to form the electrode-embedded ceramic green sheet. Is transferred onto the other ceramic green sheet or other electrode, and a method for manufacturing a laminated ceramic electronic component is provided. 2. A tackifier comprising at least one selected from polyvinyl ether and its derivatives, polyisobutylene, butyl rubber, chloroprene rubber, vinyl chloride-vinyl acetate copolymer, and chlorinated rubber. 1
A method for manufacturing the multilayer ceramic electronic component described.