JPS59222916A - Method of producing laminated capacitor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for manufacturing a multilayer capacitor, which makes it possible to manufacture the multilayer capacitor entirely in a dry process.

Conventional structure and its problems Traditionally, the manufacturing method for ceramic multilayer capacitors involves first creating a slurry (generally called a slip) consisting of dielectric powder, an organic binder, and an organic solvent, and then applying a slurry such as a doctor blade method. A film is formed on an organic film substrate using a method and dried to create a flexible film consisting of dielectric powder and an organic binder, and internal electrodes such as palladium (Pd) are screen printed on this film. Furthermore, a film consisting of a dielectric powder occupier binder on which these internal electrodes are printed is cut into a plurality of individual capacitor pieces, and then sintered at a high temperature.

According to this method, a sheet consisting of diluent powder and an organic binder is created by kneading it with an organic solvent, and in order to form a slurry on an organic film base, a large mixing machine, film forming machine, etc. is required. equipment and it takes a considerable amount of time to create the sheet.

Additionally, screen printing has conventionally been used to form electrodes (palladium). In this case, the conductor paste used for printing is made by dissolving an organic binder such as ethyl cellulose in a solvent such as turpentine and kneading this with conductor powder, and then applying this paste onto the dielectric sheet. A screen printing process is used. At this time,
The printed film thickness is closely related to the viscosity of the paste, and in order to obtain a uniform film thickness, it is important to adjust the paste viscosity. As the solvent in the paste evaporates and the viscosity changes over time, it is difficult to print using the screen printing method.
+lI has the disadvantage that it is difficult to stably obtain a uniform film thickness.

In addition, in terms of equipment and jigs, the screen printing method uses a screen made of a menon-shaped net, but it has the disadvantage that as it is used, some particles form on the screen, reducing printing accuracy. In addition, the principle of the screen printing method is to push the paste out of the screen mesh with a squeegee, which results in material loss such as paste adhering to the screen mesh. In particular, in the case of multilayer capacitors, since noble metal electrodes such as palladium are used for internal electrodes, the loss of electrode materials cannot be ignored economically.

Purpose of the Invention The present invention eliminates the above-mentioned drawbacks of the conventional technology, and eliminates the need for sheets and electrode pastes made of dielectric powder and organic binder, and does not require large-scale equipment for mixing materials, film forming, etc., or screen printing machines. The purpose of the present invention is to provide a method for easily manufacturing a multilayer capacitor in a dry process using a sleep inducer powder without using the whole material.

Structure of the Invention In order to achieve the above object, the present invention forms a bed of dielectric particles and conductive particles respectively to be charged particles, and 1j
ij. A laminate in which dielectric particles and conductor particles are deposited on a quiescent latent image formed on a dielectric material, and layers consisting of the dielectric particles and conductor particles are sequentially and alternately transferred onto an organic substrate film. The laminate is peeled off from the organic base film, the laminate is cut into individual pieces, and then sintered.

Description of Examples In general, electrophotographic techniques include the Carlson method, photoconductive toner method, photovoltaic method, TESI method (static or transfer method), permanent internal optical polarization method (PIP method), Cannon NP method, etc. ,
Among these methods, the Carlson method is the most representative method and has been greatly developed because it allows copying onto 7 iktsu papers.

The present invention relates to a manufacturing method in which a dielectric layer and an internal electrode layer are formed, laminated, and sintered to explode a multilayer capacitor using the electrophotographic technique described above.

Hereinafter, the configuration of the present invention will be explained based on the drawings.

First, the process of forming dielectric layers and internal electrode layers using electrophotographic technology will be explained based on its principles.

As shown in FIG. 1, a photosensitive substrate 1 is uniformly charged with a charger 3 and then exposed to a predetermined pattern (FIG. 2). The photosensitive portion of the photosensitive substrate is de-charged by photoconduction, and only the portion not exposed to light is recorded as an electrostatic latent image. Here, the photosensitive substrate 1 normally has properties as a dielectric material, and has such a property that when light hits the photosensitive substrate, only that portion has conductivity. A toner composed of sensitive powder and resin or dielectric powder and resin is deposited on the portion VLc where the electrostatic latent image is formed, and is developed into a photosensitive layer (FIG. 3). 8 shown in FIG. 3 is a single layer of developed toner; 6. γ is a developing device and its bias source.

The patterned toner is applied to the photosensitive substrate by passing the organic substrate film 11 or the organic substrate film 11 on which several dielectric layers and internal electrode layers have been formed from the back side while corona-covering the developed photosensitive substrate. 1 to the organic film substrate 11 (Fig. g4). Then, pressure is applied using rollers 12 and 13 (FIG. 5).

In this process, by sequentially and alternately transfer-printing the dielectric particle layer and the internal polarization layer, a laminate consisting of the dielectric particle layer and the conductor layer is formed on the organic film substrate. This laminate is peeled off from the organic film substrate and cut to the size of each laminated container piece.

Here, the dielectric layers of each piece are alternately sandwiched between polarized layers, and the positional relationship of the polarized layers is adjusted during transfer.

These pieces are sintered in a continuous furnace. In practice, the photosensitive transfer process described above is carried out in a continuous mechanical system.

More specific examples are shown below.

First, the dark resistance of the photoreceptor is 1012~1Q14Ω-
L: 1n, amorphous selenium having a resistance of 10 7 to 10 9 Ω-m when irradiated with light was used. Next is the developer, which consists of fine charged particles that make up the conductor layer or dielectric layer, and a carrier that gives appropriate triboelectrification to these particles and transports them in the latent image area. It can be divided into The charged particles constituting the conductor layer include 65 parts by weight of palladium (Pd) powder with an average particle size of 2 μm as the main component, 30 parts by weight of thermal UJP resin (styrene acrylic) as a binder, and charge control. A raw material consisting of 4 parts of chlorinated polyester as an agent is melt-kneaded, finely pulverized, and then spheroidized in an air stream at 150°C to reduce the particle size to 1Q~
The average particle size is O, as a fluidizing agent, to about 20 μm.
The material to which 1 part by weight of hydrophobic silica of about S μm was added was used.

In addition, the main component of the charged particles constituting the dielectric layer is barium titanate Ea Ti with an average particle size of 1.5 μm.
A raw material consisting of 76 parts by weight of ceramic powder mainly composed of O3, 20 parts by weight of thermoplastic resin (polyethylene) as a binder, and 3 parts by weight of chlorinated polyester as a charge control agent is melt-kneaded. After finely pulverizing 1
The particles were spheroidized in an air stream at 00°C to have a particle size of about 10 to 20 μm, and 1 part by weight of hydrophobic silica with an average particle size of about 1 μm was added as a fluidizing agent.

On the other hand, iron powder was used as a carrier (both in the case of conductor particles and dielectric cylinder particles), and the average particle size was determined by oxidizing the surface to form a stable oxide film of triiron tetroxide Fe 304. 70, Elm was used.

The development method was a magnetic brush development method. First, a Mylar film was used as an organic base film to be printed, and one dielectric layer and an internal electrode layer were alternately transfer-printed to form a laminate so that the topmost layer was the dielectric layer. Incidentally, in order to make the dielectric layer have a thickness of about 30 μm, transfer printing was performed twice for each layer. The thus obtained laminate was peeled off from the mylar film and cut into the size of a single multilayer capacitor. This green laminate was fired at 1350° C. for 2 hours. After firing, a silver-palladium external electrode was baked at 800° C. on the end of the laminate to evaluate its characteristics. As a result, the capacitance value of the laminate is 0.0
3μF, Lllllδ is 0.6%, insulation resistance is 1.5x1
It was 0.012Ω.

Effects of the Invention As described above, according to the present invention, there is no need to produce a sheet made of dielectric powder and an organic binder, and there is no need to screen print the electrode base.
It is possible to carry out the entire process of 'JJ layering in a dry process. That is, to create a capacitor structure using dielectric powder or direct conductor powder as charged particles, the processes of electrostatic latent image formation, particle deposition, and transfer are performed using so-called electrostatic printing technology. Therefore, unlike conventional methods, large equipment is not required for manufacturing, and the manufacturing process is extremely simplified. Furthermore, as mentioned above, since the present invention uses electrophotographic technology, it is possible to create internal electrode patterns with various interpole areas using one machine by changing the magnification of the optical system. This eliminates the hassle of having to change the screen printing plate each time depending on the type of product.

As described above, the present invention greatly simplifies the manufacturing process of a multilayer ceramic capacitor, and provides a method of manufacturing a multilayer capacitor that is industrially extremely advantageous.

[Brief explanation of the drawing]

FIG. 1, FIG. 2, FIG. 3, FIG. 4, and FIG. 5 are diagrams showing steps of a method for manufacturing a multilayer capacitor in an embodiment of the present invention. 1...Photosensitive substrate, 2...High voltage source for corona charger, 3... River f = sti, 4... River lens, 5... Group submergence Image, 6...Developer,
7...Bias power supply for developer, 8...
Toner image, 9...Corona charger, 10...
・High-pressure frame source for corona charging, 11... Transferred film, 12... Roller (thermal roller), 13...
...Roller (pressure roller).

Claims (1)

[Claims] forming dielectric particles and conductor particles to become charged particles; depositing the dielectric particles and conductor particles on electrostatic latent images formed on a dielectric substrate; A method for manufacturing a multilayer capacitor, in which a laminate is prepared by sequentially and alternately transferring one layer of particles onto an organic base film, the laminate is peeled off from the organic base film, the laminate is cut into individual pieces, and the laminate is sintered.