JPH0857409A - Coating method for paste - Google Patents

Abstract

PURPOSE: To provide a method for coating uniformly a conductive paste on the inner face of a through-hole of a recessed section of a ceramic sintered compact with a through-hole or a recessed section. CONSTITUTION: A ceramic sintered compact 1 after coated with a paste is out into a container 2 on a vibrator 4, and the container 2 is vibrated in one direction or more than one direction by using the vibrator 4 under the conditions of frequency of 20-200Hz and amplitude of 0.2-5mm, and excessive paste is removed by the impact force generated when the ceramic sintered compact collides with the container.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for coating a paste containing a metal as a main component with an organic vehicle on the inner surface of a through hole or a recess of a ceramics sintered body having a through hole or a recess, and in particular , A method of removing an excessive paste after coating to obtain a uniform coating thickness.

[0002]

2. Description of the Related Art When applying a paste to the entire surface of an object to be coated such as a ceramics sintered body, a method of applying by screen printing and a method of dipping the object to be coated in the paste are general. The application method by dipping is a method in which the paste can be applied at one time to the entire surface of the object to be coated of any shape, and in particular, the paste can be easily applied to the inside of the hole opened on the surface of the object to be coated.

[0003]

Conventionally, in the coating method by dipping, since the excess paste drips after the coating and the coating thickness is partially thickened, the excess paste is dropped from the lower part of the object to be coated. Alternatively, although excessive paste is absorbed, there are problems that the applied thickness of the paste is not uniform and large-scale processing is difficult.

[0004]

The present invention is a method for applying a paste containing an organic vehicle mainly containing a metal to the inner surface of a through hole or a recess of a ceramics sintered body having the through hole or the recess. The ceramic sintered body after the paste is applied is placed in a container on a shaker, and the container is vibrated in one or more directions with a frequency of 20 to 200 Hz and an amplitude of 0.5 to 5 mm, so that the ceramic sintered body is contained in the container. Is a method of applying a paste, which makes it possible to remove excess paste due to collision between the sintered bodies and impact force when the sintered bodies collide with the container.

Further, the inner surface of the container is resin-coated, or the bottom surface has an opening size of 0.5 × 0.5 mm.
As described above, the paste coating method is characterized in that a resin mesh having a size equal to or smaller than the outer shape of the object to be coated is provided.

[0006]

After the paste is applied by the dip method, the excess ceramic paste is removed by putting the ceramic sintered body after the paste application in a container on a shaker and setting the frequency of the container to 2
By vibrating at an amplitude of 0 to 200 Hz and an amplitude of 0.5 to 5 mm, the ceramic sintered bodies randomly move in the container, the sintered bodies collide with each other, and the impact force when the sintered body collides with the container. To remove excess paste. In this way, it becomes possible to easily form a large amount of a layer of the electrode paste having a uniform thickness on the inner surface of the through hole or the recess of the ceramic sintered body. Furthermore, the inner surface of the container is coated with a resin to prevent chipping of the ceramic sintered body,
Or the opening size made of resin on the bottom is 0.5 x 0.5 mm
As described above, by providing a mesh that is smaller than or equal to the outer shape of the ceramic sintered body, it is possible to prevent the removed paste from passing through the mesh, being collected at the bottom of the container, and being reattached to the ceramic sintered body.

[0007]

Embodiments of the present invention will be described below. In this embodiment, an electrode paste containing Ag as a main component is applied to a ceramics sintered body by a dipping method, the ceramics sintered body after dipping is placed in a container, and the container is vibrated to remove excess paste. The case of doing is described.

(Embodiment 1) In this embodiment, a barium titanate-based ceramics sintered body is used, and 5.8 × 5.8 ×
On the inner surface of the through hole of the coaxial type ceramics sintered body, which is a 7.8 mm prism, and which has a hole of φ1.8 × 7.8 mm that passes through the center of the 5.8 × 5.8 mm surface at both ends, The application of the electrodes was performed with 300 pieces as one lot. The Ag electrode paste is made of an organic component such as ethyl cellulose, α-terpineol, a plasticizer and has a viscosity of 10 to 80 dPa ·.
s. As shown in FIG. 1, the container is a cylindrical container 2 made of stainless steel and having a diameter of 200 mm and a height of 50 mm, and the inner surface of the container is coated with a silicone rubber 3 to prevent the ceramic sintered body from being applied. Was used.

The coaxial ceramic sintered body 1 is dipped in an Ag electrode paste, coated with the paste on the entire surface, and then placed in a container 2 with a frequency of 50 Hz and an amplitude of 0.2 to 3 m.
It was vibrated vertically on a shaker 4 at m to shake off the excessively applied paste, and the paste was collected by adhering to the surrounding wall surface. At that time, the hot air was blown into the container by the hot air blower 7 to accelerate the drying of the paste. By repeating this step, the Ag electrode was applied to a predetermined thickness, and then dry barrel polishing was performed to remove the Ag from the portion other than the inner surface of the through hole of the ceramic sintered body. after,
Baking of Ag was performed. Table 1 shows the coating thickness of Ag after six coatings.

[0010]

[Table 1]

As shown in Table 1, the coating thickness has an amplitude (0.
The larger 2 → 3 mm), the paste viscosity (80 → 10
The lower the dPa · s), the thinner the coating thickness. Moreover, the formed Ag electrode uniformly covered the entire inner surface of the through hole of the ceramic sintered body, and the variation in the film thickness was ± 20% under all conditions. Especially, 20
When the coating thickness was less than μm, the variation was ± 12% or less, and a very uniform film was obtained.

(Embodiment 2) In this embodiment, similarly to Embodiment 1, a barium titanate-based ceramics sintered body is used, and a prism of 5.0 × 5.0 × 8.2 mm is provided with 5 at both ends. 0.0 x
300 Ag electrodes were applied as one lot to the inner surface of the through hole of the coaxial type ceramics sintered body in which a hole of φ2.0 × 8.2 mm passing through the center of the surface of 5.0 mm was drilled. , Ag electrode paste is ethyl cellulose,
It is composed of an organic component such as α-terpineol and a plasticizer and has a viscosity of 10 to 80 dPa · s. As shown in FIG.
The container is made of stainless steel and has a diameter of 200 mm and a height of 50 mm.
A stainless steel mesh with an opening of 2 × 2 mm and a wire diameter of 0.3 mm was coated with Teflon to prevent the ceramics sintered body from being sprayed and to collect the removed paste at the bottom of the container with an interval of mm. The mesh 5 was provided.

The coaxial type ceramics sintered body 1 is dipped in an Ag electrode paste, coated with the paste on the entire surface, and then placed in a container 2 and is vertically moved on a shaker 4 at a frequency of 50 Hz and an amplitude of 1 to 5 mm. Then, the excessively applied paste was shaken off and collected at the bottom of the container below the mesh. Reference numeral 6 indicates the status of the recovered paste. At that time, the drying of the paste was promoted by sending warm air from the warm air fan 7 into the container. By repeating this step, the Ag electrode was applied to a predetermined thickness, and then dry barrel polishing was performed to remove the Ag from the portion other than the inner surface of the through hole of the ceramic sintered body. After that, A
b was baked. Table 2 shows the coating thickness of Ag after six coatings.

[0014]

[Table 2]

As shown in Table 2, the larger the amplitude of the coating, and the lower the paste viscosity, the thinner the coating thickness. Further, the formed Ag electrode uniformly covered the entire through hole of the ceramic sintered body, and the variation in the film thickness was ± 20% under all conditions. Especially, 20
When the coating thickness was less than μm, the variation was ± 12% or less, and a very uniform film was obtained.

Further, in the present embodiment, only the case of vibrating in the vertical direction has been described, but it goes without saying that the vibration can be applied in any direction of one or more directions.

[0017]

As described above, a ceramic sintered body having through holes or recesses is coated with a paste containing a metal as a main component and an organic vehicle by a dipping method, and then the ceramic sintered body is shaken. Put in a container on the machine, and move the container in one or more directions at a frequency of 20-2.
By vibrating at a frequency of 00 Hz and an amplitude of 0.2 to 5 mm, the ceramic sintered bodies move randomly inside the container, and the excessive paste is removed by the impact force when the sintered bodies collide with each other or the sintered body collides with the container. By doing so, it becomes possible to easily form a layer of the electrode paste having a uniform thickness on the inner surface of the through hole or the recess of a large amount of the ceramics sintered body.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an outline of a coating apparatus used in Example 1 in a cross section.

FIG. 2 is an explanatory view showing an outline of a coating apparatus used in Example 2 in section.

[Explanation of symbols]

 1 coated object (ceramics sintered body) 2 container (stainless steel) 3 silicone rubber 4 shaker 5 mesh 6 recovered paste 7 warm air blower

Claims (3)

[Claims] 1. A method of applying a paste comprising a metal as a main component and an organic vehicle to the inner surface of the through hole or the recess of a ceramic sintered body having the through hole or the recess, and the ceramic sintering to which the paste is applied. Place the body in a container and move the container in one or more directions at a frequency of 20.
A method for applying a paste, which comprises vibrating the ceramic sintered body at a frequency of 200 Hz and an amplitude of 0.2 to 5 mm to impact the ceramic sintered body to remove an excessive paste. 2. The paste applying method according to claim 1, wherein the inner surface of the container is resin-coated. 3. The paste application method according to claim 1, wherein the opening size is 0.5 × at the bottom of the container.
A method for applying a paste, which comprises providing a resin mesh having a size of 0.5 mm or more and having a size equal to or smaller than an outer shape of a ceramic sintered body as an object to be applied.