JPH0845773A - Method for manufacturing laminated body - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a method for manufacturing a small-sized laminated body at low cost. A slurry composed of ceramic powder and an organic binder is printed and laminated by a screen printing method several times as a protective layer 4, and an internal electrode paste 3 and the slurry are screen-printed on the slurry so as to be laminated alternately.
The counter electrode layer 5 is formed, and a protective layer 6 is printed and laminated thereon several times. Further, compared with the screen used for the dielectric effective layer, the screen for printing the protective layer has a large aperture ratio, a thick mesh, and a thick emulsion, and is thickly coated by one printing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a laminate produced by screen printing.

[0002]

2. Description of the Related Art In a laminated body such as a laminated ceramic capacitor or laminated inductor having a structure in which a metal conductor layer and a dielectric layer are alternately laminated, a ceramic powder is conventionally manufactured by a doctor blade method. Slurry mixed with and an organic binder is formed into a sheet, that is, a green sheet, on which a metal conductor paste is screen-printed, a plurality of layers are superposed, and a conductor paste to be a protective layer is printed above and below the metal conductor paste. There is known a method of obtaining a laminated body by laminating a plurality of green sheets which are not formed and pressing them.

Further, in recent years, there has been a great demand for miniaturization of chips, and in order to meet these demands, thinning of the ceramic effective layer (or green sheet) and more multilayers are essential conditions. Is coming.

When the film thickness of the green sheet is set to 10 μm or less by using the conventional doctor blade method, there are problems such as generation of static electricity and breakage due to weak strength due to the thinness of the green sheet when handling the green sheet. there were.
In addition, it was difficult to establish mass production conditions, including problems such as equipment. On the other hand, as a method for manufacturing a green sheet having a film thickness of 10 μm or less, there is a screen printing method. Therefore, the screen printing method is generally applied to laminate the ceramic effective layer and the internal electrode pattern to manufacture the laminated body, and the sheet lamination method is applied to manufacture the ceramic protective layer.

[0005]

However, since the laminated body produced by this method is a film forming method in which the ceramic effective layer and the protective layer are different, compared with the case where the ceramic effective layer is also sheet laminated, However, there is a problem in that the cost is high, the production space needs to be large, and the stacking takes time, resulting in high cost.

The object of the present invention is to make equipment inexpensive and
It is an object of the present invention to provide a method for manufacturing a laminated body, which has advantages such as good productivity and can be obtained at a low cost and in a small size.

[0007]

According to the present invention, a ceramic effective layer, an internal electrode pattern and a ceramic protective layer are formed, and the ceramic effective layer and the internal electrode pattern are printed and laminated by a screen printing method. A method of manufacturing a laminated body can be obtained.

According to the present invention, in the above-mentioned method for producing a laminated body, screen printing is used, and the thickness of one screen printing is 30 μm when laminating the ceramic protective layer.
It is possible to obtain a method for manufacturing a laminated body, which has a thickness of 200 μm or less.

According to the present invention, in the above-mentioned method for producing a laminate, 4.5 wt% of polyvinyl butyral to the ceramic powder is added to the ceramic powder as a binder, and the solvent is ethyl cellosolve or butyl carbitol. A method for producing a laminate, characterized in that the ceramic protective layer is printed by a stainless screen having a mesh size of 40 to 150 mesh using a ceramic paste mixed and dispersed and having a viscosity adjusted to 50 to 400 poise. .

[0010]

According to the manufacturing method of the present invention, the protective layer and the dielectric effective layer can be laminated by screen printing in a consistent manner, so that the conventionally required steps such as film formation and punching and related equipment are unnecessary. Becomes Therefore, there are advantages that the productivity is improved, the cost of equipment and the like is eliminated, and the laminate can be manufactured at low cost. In addition, in the print lamination of the protective layer, a screen having a large aperture ratio, a large mesh thickness, and a thick emulsion thickness is used as compared with the screen used for forming the dielectric effective layer. Since the coating is applied, the number of times of lamination is small, the productivity is high at high speed, and the laminate can be mass-produced.

[0011]

Embodiments of the present invention will be described with reference to the drawings.

In the present invention, first, in order to measure the thickness in one screen printing, the number of meshes of the stainless screen is 40, 60, 80, 100, 150, 20.
0,250,300, the viscosity of the ceramic paste is 5
Prepare 0, 100, 200, 400 poises,
A printing experiment was conducted. The particle size of ceramic paste is 1
Polyvinyl butyral as a binder is added to a ceramic powder having a size of less than or equal to μm, and 4.5 wt.
%, And mixed and dispersed with a solvent of ethyl cellosolve and butyl carbitol. The results are shown in FIG. 1 as the relationship between the number of screen meshes and the printing thickness.

From FIG. 1, it can be seen that the higher the viscosity, the smaller the number of screen meshes and the greater the printing thickness. In Fig. 1, the thickest printing thickness is 400 poise, which has the highest viscosity, and the smallest mesh number, 40 (lines /
Inch), a printing thickness of 200 μm is possible. On the other hand, in order to secure 30 μm or more, the viscosity should be 5
It can be seen that the mesh number is required to be 100 (lines / inch) or less at 0 poise, and the mesh number is 200 (lines / inch) or less when the viscosity is 100 poise. Therefore, 2
To secure a printing thickness of 00 μm or less and 30 μm or more, a stainless screen mesh size of 40 to 150 (lines / i
nch), using a ceramic paste having a viscosity of 50 to 400 poise.

In FIG. 1, in the respective viscosity curves, the right end is not printable because the number of meshes is large, the ceramic paste on the mesh does not come off easily, and the printed surface becomes a pinhole. Some areas are not printed,
It means that the printing surface has a failure, which is an unsuitable condition for printing and stacking. Also, at the left end of the curve of viscosity 50,100 poise, printing is not possible because the viscosity is low.
Since the mesh is rough, it means that the ceramic paste is likely to come off from the mesh, which is an obstacle to printing, which is an unsuitable condition for print lamination.

Next, the present invention will be described in detail with reference to FIG. 2 using the results of FIG. 1 as an example of the production of a laminated ceramic capacitor having a counter electrode structure.

Dielectric constant ε = having a lead-based perovskite structure
A solvent having ethyl cellosolve or butyl carbitol and a binder of polyvinyl butyral were mixed and dispersed in a powder of 14,000 ferroelectric ceramics having a particle size of 1 μm or less to prepare a screen-printable ceramic slurry.

When the ceramic slurry is printed and dried by screen printing to form a ceramic laminate, 1
After screen-printing a single time, the protective layer 1 becomes 100 after drying.
The thickness of the dielectric effective layer 2 is 10 μm so that the screen mesh 100 from FIG.
Using a combination of 0 poise, the protective layer 1 screen has a stainless steel 100 mesh, a mesh thickness of 200 μm,
The emulsion thickness was 40 μm, the ceramic paste had a viscosity of 400 poise, while the dielectric effective layer 2 screen had a stainless 200 mesh, a mesh thickness of 60 μm, the emulsion thickness was 10 μm, and the ceramic paste had a viscosity of 50 poise.
Both screen patterns are 100mm x 100m
m.

Further, as the internal electrodes, Ag and Pd are 70:
By using a commercially available alloy paste of No. 30, printing conditions are set so that printing can be performed on a dielectric effective layer with a stainless steel 400 mesh screen, and printing and drying are performed.
An internal electrode pattern 3 having a length of 3.89 mm, a width of 1.39 mm, and a thickness of 2 μm was formed.

Next, the manufacturing procedure will be described. First, the ceramic slurry was printed and laminated three times on the screen for the protective layer 1 to form the protective layer 4 having a thickness of 300 μm, and then the internal electrode paste was shifted by 0.26 mm each in the length direction of the pattern to obtain the dielectric layer. The opposing electrode layer 5 of the capacitor was formed by alternately printing and laminating the body effective layer 2, and 100 layers of the dielectric effective layer 2 were printed and laminated on the screen for the dielectric effective layer 2.

After that, the ceramic slurry was printed and laminated three times on the screen for the protective layer 1 to give a thickness of 300.
A protective layer 6 having a thickness of μm was provided to obtain a laminated body which was a ceramic capacitor having a design of 4.7 μF.

This laminate was cut, debindered at 400 ° C. for 7 hours, and after removing the binder, it was dried at 900 ° C. for 4 hours.
It was fired for a time to obtain a sintered body.

An Ag-Pd paste is applied as a terminal electrode to the end surface of this sintered body, which is the internal electrode take-out port.
Sintering was performed at 50 ° C. to obtain a ceramic capacitor.

As described above, in this embodiment, the process and the lamination time of the monolithic ceramic capacitor can be shortened and the productivity can be improved. Also, a small monolithic ceramic capacitor could be manufactured. Even if the protective layer 4 is formed by the doctor blade method and only the protective layer 6 is formed by the screen printing method, the sheet stacking step can be omitted.

The method for producing a laminated body of the present invention can be applied to the production of laminated bodies such as laminated inductors and laminated varistors in addition to this embodiment.

[0025]

According to the method for manufacturing a laminate of the present invention, it is possible to obtain an inexpensive and small-sized laminate because it is not necessary to laminate sheets.

[Brief description of drawings]

FIG. 1 is a diagram showing the relationship between the number of screen meshes and the print thickness depending on the viscosity.

FIG. 2 is a perspective view illustrating the structure of a monolithic ceramic capacitor according to an embodiment of the present invention.

[Explanation of symbols]

 1 Protective layer (per screen printing) 2 Dielectric effective layer (per screen printing) 3 Internal electrode pattern 4, 6 Protective layer 5 Counter electrode layer

Claims (3)

[Claims] 1. A method for manufacturing a laminate, comprising a ceramic effective layer, an internal electrode pattern and a ceramic protective layer, wherein the ceramic effective layer and the internal electrode pattern are printed and laminated by a screen printing method. 2. The method for manufacturing a laminate according to claim 1, wherein the thickness of one screen printing when laminating the ceramic protective layer is 30 μm or more by screen printing.
A method for producing a laminated body, which has a thickness of 00 μm or less. 3. The method for producing a laminate according to claim 1, wherein 4.5 wt% of polyvinyl butyral is added to the ceramic powder as a binder, and ethylcellosolve and butylcarbitol are added to the ceramic powder. 40-150 by using a ceramic paste that is mixed and dispersed with the above solvent and the viscosity is adjusted to 50-400 poise.
A method for manufacturing a laminate, comprising forming the ceramic protective layer by printing with a stainless screen having a mesh range.