JPS63314889A - Manufacture of porcelain wiring substrate - Google Patents

Abstract

PURPOSE:To reduce a manufacturing cost and to improve quality by transferring an organic material which contains metal and is charged in polarity reverse to that of charge on an unsintered magnetic substrate in a predetermined shape to the substrate, fixing and then sintering it. CONSTITUTION:A charging brush 3 is brought into contact with the conductive layer 1 of a drumlike photosensitive unit 1, and a DC voltage of a DC power supply 4 is applied between the brush 3 and the layer 1. With the brush as a negative electrode the surface of the unit 2 which rotates in a direction of an arrow is corona charged to negative. The unit 2 is irradiated with the light 6 of a fluorescent lamp 5 through a liquid crystal shutter 7 to form an electrostatic latent image. An organic material 10 which contains PdO and is charged to positive is covered on the unit 2, and developed. The negative potential of a power supply 40 is applied to an unsintered porcelain substrate 11 to conduct a corona discharge while moving the substrate 11 in a direction of an arrow 12, thereby transferring the organic material to the surface of the unit 2. The substrate 11 is heated by an infrared ray 14 to be fixed, and sintered in an electric furnace.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a method of manufacturing a ceramic wiring board used for, for example, a multilayer ceramic wiring board, a laminated ceramic capacitor, and the like.

(Prior Art) Conventionally, a ceramic wiring board is produced by first forming a mixture of a ceramic composition raw material and an organic binder onto a polyester film using a doctor blade method or the like to obtain an unsintered ceramic substrate called a green sheet. Further, a mixture of an electrode material, a resistor material, and an organic binder is coated on the unsintered ceramic substrate by screen printing, and laminated.
After crimping, it was cut into a predetermined shape and sintered.

(Problem to be solved by the invention) Electrode on an unsintered porcelain substrate by the above method.

In order to form resistors and the like, it is necessary to use a screen printing method, and for this it is necessary to prepare in advance a plate that matches the printing shape. For this reason, in the past, costs have been forced to increase during small-volume production or custom production, and there have been other inconveniences such as longer delivery times. Furthermore, there are large variations depending on the printing method, and it is necessary to strictly control the conditions.

SUMMARY OF THE INVENTION The present invention aims to eliminate the above-mentioned drawbacks, and its purpose is to provide a manufacturing method capable of producing a ceramic wiring board of high quality and low cost.

[Configuration of the Invention (Means for Solving the Problems)] The present invention provides a method in which the surface of a corona-charged unsintered porcelain substrate is
Transferring an organic substance containing a metal compound and charged with a charge of opposite polarity to the surface charge of the unsintered porcelain substrate into a predetermined shape, fixing the bond, and sintering the unsintered porcelain substrate. At the same time, the organic matter is burned away.

(Function) According to the above manufacturing method, organic matter is burned out at the firing temperature of the ceramic substrate, and electrodes, resistors, etc. made of metal compounds can be formed on the surface or inside of the ceramic substrate, and the ceramic wiring board can be manufactured. It is possible to reduce costs and improve quality.

(Example) Hereinafter, the present invention will be specifically explained with reference to Examples.

1 to 7 show one embodiment of the present invention.

First, in a dark place, as shown in FIG. 1, a charging brush 3 is brought into contact with the surface of a drum-shaped photoreceptor (hereinafter referred to as "photoreceptor") 2 provided with a conductive layer 1 made of AJ2 (aluminum). A DC power source 4 is provided between the charging brush 3 and the conductive layer 1.
A higher DC voltage is applied (step 31). Ground side (
The conductive layer 1) is used as a positive electrode, and the brush 3 side is used as a negative electrode. Further, an optical semiconductor (α-3i) is applied to the photoreceptor 2.

When the photoreceptor 2 is thus rotated in the direction of the arrow shown in the figure, the surface of the photoreceptor 2 is negatively charged with corona.

Next, the surface of the photoreceptor 2 is irradiated with fluorescent light (step 32). At this time, as shown in FIG. 2, a liquid crystal shutter 7 is interposed between the fluorescent lamp 5 and the photoreceptor 2, and this liquid crystal shutter 7 allows the fluorescent light to be applied to a portion of the ceramic wiring board corresponding to the desired electrode formation location. The photoreceptor 2 is optically masked so that the lamp light 6 does not hit it. The blackening control of the liquid crystal shutter 7 is electrically performed by a control means (not shown). The portion irradiated with the fluorescent lamp light (indicated by 8) changes from insulating to conductive due to the properties of α-3i, which is a photosemiconductor, and the charge previously charged on the surface is lost. The portion (indicated by 9) that is not exposed to the fluorescent lamp light due to the optical masking maintains insulation and does not lose charge. This is called an electrostatic latent image.

Next, as shown in FIG. 3, an organic substance 10 containing PdO (palladium M) and positively charged in advance is photographed on the surface of the rotating photoreceptor 2, and the electrostatic latent image is developed. (Step S3).

On the other hand, BaT! 03 (Dielectric) A mixture of raw materials and an organic vibrator is formed into a sheet by a doctor blade method, and this is prepared as an unsintered ceramic substrate.

Then, as shown in FIG. 4, this unsintered porcelain substrate 11 is brought into contact with the surface of the photoreceptor 2 (on which the electrostatic latent image has been developed), and as the photoreceptor 2 rotates, Move in 12 directions. At this time, the power source 4 is connected via the charging brush 30.
By applying a negative potential of 0 to the unsintered ceramic substrate 11, a negative corona discharge is performed, and the organic matter (subjected to development) on the surface of the photoreceptor 2 is transferred to the unsintered ceramic substrate 11 ( Step 34). Even after this transfer is completed, organic substances and residual charges still exist on the surface of the photoreceptor 20.

Therefore, as shown in FIG. 5, the surface of the rotating photoreceptor 2 is irradiated with fluorescent light from a fluorescent lamp 50 to eliminate static electricity, and then cleaned with a brush 13. Then, the process returns to step S1.

Next, as shown in FIG. 6, the unsintered porcelain substrate 11 on which the transfer was performed in step S4 is conveyed by the roller 15 in the direction of the arrow 17, and the substrate surface temperature is lowered to 120.
It is heated by the infrared heater 14 to about 0.degree. C. (step S5). This heating fixes the organic matter on the unsintered ceramic substrate 11. This is called an unsintered porcelain wiring board.

In particular, when manufacturing a multilayer capacitor using a plurality of ceramic wiring boards, j
For example, 50 unsintered porcelain wiring boards are stacked and 1
After thermocompression bonding at 20° C. and 100:3/cat, it is cut into a predetermined shape (step 36), and then baked in an electric firing furnace with an internal temperature of 1350° C. for 2 hours (step 37). Thereafter, as shown in FIG. 7, a mixture of Ag (silver) and an organic binder is applied to both ends of the stacked unsintered ceramic wiring board group 18, and the end electrodes 19a, 19 are coated with a mixture of Ag (silver) and an organic binder.
form b. This end electrode formation can be performed, for example, by a screen printing method. In FIG. 7, reference numeral 20 indicates an internal electrode made of PdO, and reference numeral 21 indicates a dielectric material (Ba T! 03 ). and make it 12
After drying in an atmosphere of 0°C, a multilayer capacitor is obtained by sintering at 800°C (step 39).

Here, a comparison is made between the screen printing method used in the conventional manufacturing method of a ceramic wiring board and the electrostatic fixing printing method in this embodiment.

First, in the screen printing method, the pattern to be printed is fixed by stretching Tetoron fibers onto a metal frame, and then a plate film is created using an optical method on top of the pattern to cover the areas other than the necessary image lines. The fixed printing method can be easily carried out by controlling the liquid crystal shutter 7 according to a preset program.

Furthermore, while the screen printing method requires the plate to be attached to the printing machine, the electrostatic fixing printing method does not require such an attachment step.

Next, in the screen printing method, ink is poured into a frame, and a spatula-shaped rubber plate is pressed against the inner surface of the screen to allow the ink to pass to the outer surface of the screen, and printing is performed with this passing ink. However, in the electrostatic fixing printing method, such an operation is not necessary and, as is clear from step 4, it is performed by negative corona discharge.

Furthermore, while screen printing requires plate replacement and ink viscosity adjustment, electrostatic fixing printing does not require these.

Furthermore, screen printing requires drying at a temperature of 120°C to remove the solvent after printing, whereas electrostatic printing requires heat treatment at approximately 120°C for fixing, but does not use solvents. (Rather than ink, a powder mixture of metal compounds and organic substances is used.) No drying is required.

As described above, in this example, a ceramic wiring board is created using the electrostatic fixing printing method, and the organic matter is burned off at the firing temperature of the ceramic board, and electrodes made of metal compounds are formed on the surface or inside of the ceramic board. , resistors, etc. can be formed, and for example, cost increases can be suppressed even during small-volume production or custom production, and desired ceramic wiring boards can be manufactured at low cost. In addition, the quality of the product is high because there is no large variation in the product unlike when screen printing is used.

In the above embodiment, a case was explained in which a multilayer capacitor was obtained, but by laminating a plurality of ceramic wiring boards obtained by the manufacturing method according to the present invention, a multilayer ceramic board of 1 q.
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Although one embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to the above embodiment, and that various modifications can be made.

[Effects of the Invention] As detailed above, according to the present invention, it is possible to provide a method for manufacturing a ceramic wiring board that can easily improve quality and reduce costs.

[Brief explanation of drawings]

1 to 7 do not show one embodiment of the present invention.
Figure 2 is an illustration of corona charging on the surface of a photoreceptor, Figure 2 is an illustration of irradiation of fluorescent light onto the surface of the photoreceptor, Figure 3 is an illustration of development of an electrostatic latent image, and Figure 4 is an illustration of the developed electrostatic latent image. An explanatory diagram of the transfer of an electrostatic latent image, Fig. 5 is an explanatory diagram of the removal of organic substances and residual charges on the surface of the photoreceptor, Fig. 6 is an explanatory diagram of the fixation of organic substances, and Fig. 7 is an explanatory diagram of the formation of end electrodes of a multilayer capacitor. It is a diagram. 2...Photoreceptor, 10...Organic substance, 11
...Unsintered porcelain substrate. Seventh cause

Claims (1)

[Claims] An organic substance containing a metal compound and charged with a charge of opposite polarity to the surface of the unsintered ceramic substrate is transferred to a predetermined shape on the surface of the corona-charged unsintered ceramic substrate, and the organic substance is fixed. 1. A method for manufacturing a ceramic wiring board, comprising: sintering the unsintered ceramic substrate and burning out the organic matter.