JPH03151258A - Manufacture method for anisotropic electrically conductive ceramic composite - Google Patents

Abstract

PURPOSE:To make it possible to obtain an anisotropic electrically conductive ceramic composite easily by a method wherein after laminating a plurality of green sheets of which main component is a ceramic powdery having insulating properties and a plurality of fabrics which have electrical conductivity only in a designated direction after sintering, they are pressed and sintered under an air atmosphere. CONSTITUTION:A green sheet 1 is a forming body before sintering, which consists of a ceramic powder, organic bonding medium and a plasticizer, etc., it necessary. A fabric 2 has electrical conductivity only in a designated direction after sintering, and is constituted by weaving a fiber 2a which extends in A direction and a fiber 2b which extends in B direction which is rectangular to the direction A. After laminating the green sheets 1 and the fabrics 2 by an optional quantity, they are pressed, and the fabrics 2 are buried in the green sheets 1, and a laminated body 3 with a designated thickness is obtained. Then, the laminated body 3 is heated in a heating oven, and is degreased under an air atmosphere and sintered to obtain an anisotropic electrically conductive ceramic composite. By this method, an anisotropic electrically conductive ceramic composite can be easily obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention is... Insulating (-A conductor or resistor is arranged at high density in a laminate.)Relates to a method for manufacturing an anisotropically conductive ceramic composite having conductivity only in a predetermined direction.

(Prior Art) "Ceramics 201986" is a composite of electrically insulating ceramics and conductive materials.

No. 7, page 603'' describes a β-3i, N, /TiN composite synthesized by a chemical vapor deposition method (CVD method). The composite contains C in amorphous silicon nitride (Si, N4).
It is made by decomposing titanium nitride (TiN) using the VD method. TiN with a diameter of about 5 nm is oriented in one direction. Therefore.

The composite has anisotropic conductivity in that it exhibits no conductivity in one direction.

Also, JP-A-62-101454, JP-A-63-
Publication No. 99955. JP-A-63-99956 and JP-A-63-99957 disclose that a pattern of a predetermined shape made of a photosensitive resin is formed on a substrate such as a ceramic green sheet, and then this pattern is formed. By sintering a paddle layered body obtained by laminating a ceramic green sheet and another ceramic green sheet, the photosensitive resin is disappeared by thermal decomposition, and a ceramic sintered body having pores of a predetermined shape is obtained. A method is disclosed. As an application of this method, an anisotropically conductive ceramic composite can be obtained by injecting molten metal into the pores after the pores are formed.

(Problem to be solved by the invention) The ceramic composite disclosed in the above document is.

Because it is created using the CVD method, the conductor may be cut in the middle of the composite, or it may be in contact with another conductor, and it may not exhibit conductivity in the plane direction of the composite. be.

In addition, with the CVD method, a composite material with a thickness of about 2 mm (R)
Because I can't create 2 or L.

The resulting ceramic composite was of poor practical use.

Also. In the manufacturing method disclosed in the above-mentioned publication, the step of forming a dry fill resist on a green sheet is complicated, and a high temperature process for press-fitting molten metal cannot be avoided.

The present invention solves the problems of the conventional art, and its purpose is to provide an anisotropically conductive material in which a conductor or a resistor is densely arranged in a ceramic having a desired thickness. An object of the present invention is to provide a method for easily manufacturing a ceramic composite.

(Failure to solve the problem) The method for producing anisotropically conductive ceramics of the present invention is as follows.

The method is characterized in that a plurality of green sheets containing insulating ceramic powder as a main component and a fabric that is conductive only in a predetermined direction after sintering are laminated and then pressed together and sintered in an air atmosphere. First method.

After sintering, one or more fabrics that are conductive only in a predetermined direction are laminated in a mold with voids, and then the voids of the mold are filled with a slurry mainly composed of insulating ceramic powder (
- make a green body including the fabric, and make the green body 1
A second method characterized in that two or more pieces are laminated, crimped, and sintered in an air atmosphere, and a fabric that has conductivity only in a predetermined direction after sintering is placed in a slurry containing insulating ceramic powder as a main component. - one or more sheets of the fabric, a green body containing the fabric is made, one or more of the green bodies are laminated and crimped,
A third method is included, characterized in that the sintering is carried out in an air atmosphere, whereby the above object is achieved.

The means will be explained in the order of methods 1, 2 and 3 with reference to two drawings.

First, manufacturing method 1 will be explained.

Green sheet 1 shown in FIG. 1 used in the present invention
is a pre-sintered compact made of ceramic powder, an organic binder, a plasticizer if necessary, and the like.

Examples of the ceramic powders mentioned above include alumina, zirconia, magnesia, and spinel.

Mullite, crystallized glass, etc. or Ban-31o2-B*
Oa-[:an system, Mg[]-5i02-Can system,
B2 [335102 series, Ph1l B2L Sin
system, Can-3iO2Can-3iO2- system, Pb
O5iO2BJ3-4: The main component is glass frit such as aO type.

They may be used alone or in combination of two or more.

, and the organic binder 2f described in h. For example, unsaturated polyester 2 polyurekne. Polyvinyl butyral.

Polyvinyl alcohol 9 polymethacrylate.

Cellulose, dextrin polyethylene, wax 7 starch. Examples include polymeric materials such as casein. Examples of the plasticizer include dioctyl phthalate, dibutyl phthalate, and polyethylene glycol.

Any method may be used to produce the green sheet. For example, the green sheet may be made of the above-mentioned ceramic powder. Mix organic binder, plasticizer, and solvent.

The resulting mixture was injection molded, extrusion molded, and compression molded.

Preferably, it is molded by a molding method such as casting.

In particular, a slurry-like mixture is applied onto a substrate such as a polyester film or glass plate using a doctor blade method, and then dried. Preferably, the molding is performed by a so-called doctor blade method.

Examples of the above-mentioned solvents include methanol, ethanol, butanol, propatool, ethyl acetate, benzene, toluene, xylene, water, and the like.

The amount of the organic binder and solvent to be added may be determined as appropriate depending on the manufacturing conditions of the green sheet, etc., but preferably the amount of the organic binder is 5 to 30 parts by weight per 100 parts by weight of the ceramic powder.
Add 20-100 parts by weight of Part 9 solvent.

The fabric 2 shown in FIG. 1 used in the present invention has conductivity only in a predetermined direction after sintering.

This fabric 2 is constructed by weaving together a fabric 2a extending in the entry direction and fibers 2b extending in the direction B orthogonal to the entry direction. The fibers 2a in the incoming direction are each fiber independent (7
Has electrical conductivity.

Conductive transverse fibers 2a in the entrance direction of the fabric 2 shown in FIG.

Fibers that exhibit non-conductivity after sintering or fibers that disappear after sintering may be woven between 2a. Examples of fibers that are electrically conductive after sintering and fibers that are electrically non-conductive after sintering include fibers such as those made of nickel, nine inconel alloys, and molybdenum.

For example, 5iC-TiC system. Examples include Al2O3-based fibers and glass-based fibers. Fibers that disappear after sintering include carbon fiber, nylon type, polyester type,
Examples include organic synthetic fibers such as vinylon type and acrylic type fibers, and these fibers become carbon dioxide gas and are released into the air when sintered.

As the fibers 2b in direction B in FIG. 1, the above-mentioned fibers 9 that exhibit non-conductivity after sintering or fibers that disappear after sintering can be used. The fibers 2a in the input direction and the fibers 2b in the B direction may be appropriately determined depending on the sintering temperature used and the like.

Obtained using the method described above. A desired number of green sheets 1 and woven fabrics 2, which are conductive only in the inward direction after sintering, are laminated and then pressed together to bury the woven fabrics 2 in the green sheets 1 to form a laminate 3 having a predetermined thickness.

The number of stacked green sheets 1 and fabric 2 is as follows.

It may be determined as appropriate depending on the size of the desired ceramic composite, but if it is too thick, it will be difficult to pressure bond, so the thickness of the green sheet 1 and the fabric 2 should be 10~=
In the case of an order of 100 tomo, approximately 10 to 1000 pieces is recommended. If it is desired to obtain a thicker layer, a plurality of laminates that have been laminated and crimped together may be laminated again and crimped. The conditions for crimping may be determined as appropriate. Preferably 30~
It is appropriate to apply pressure at 120° C. and a pressure of 1 to 100 kg/em for 1 to 10 minutes. Through this step, a ceramic composite 3 before sintering can be obtained. Next, the laminate 3 is heated in a heating furnace, degreased and sintered in an air atmosphere to obtain an anisotropically conductive ceramic composite as shown in FIG. The sintering temperature depends on the ceramic powder used.

It may be determined as appropriate depending on the type of fiber. Preferably 1
~b By heating up to 400-600°C while turning.

The laminate 3 is degreased and then heated again to 700-16
Sinter at 50°C for 1-24 hours.

Second method The second method will be explained.

As a textile that is conductive only in a certain direction.

The one used in the first method can be used.

First, a plurality of fabrics 4-1 are laminated in a mold having a void. In order to prevent the conductive fabrics from coming into contact with each other, a fabric that becomes entirely non-conductive after sintering may be sandwiched between the conductive fabrics. After that, the cavity of the mold is filled with a green slurry whose main component is insulating ceramic powder. A green body containing the fabric is formed. As for its formation method. Examples include pressure molding and injection molding under reduced pressure. If necessary,
After the green body is formed in the cavity of the mold, a part of the mold may be removed to scatter the solvent, etc. in the molded body.

The green slurry forming the green body used in the method includes ceramidox powder, an organic binder, a solvent,
If necessary, it consists of a plasticizer, etc. Ceramic powder, organic binder, solvent 1 The plasticizer can be of the type used to create the green sheet in the first method, and the organic binder Also, the amount of solvent used can be the same as that used to create the green sheet. One or more of the obtained green bodies are laminated and then press-bonded.

As the conditions for crimping, the same conditions as in the first method can be used.

Then degreasing as in the first method. By sintering method, degreasing,
It is possible to perform sintering.

Third method next. The third method will be explained.

First, a mold is filled with a green slurry whose main component is ceramic powder. For the purpose of easily embedding the fabric, the temperature of the slurry may be increased to lower the viscosity in step 17. The slurry above is ceramic powder. It consists of an organic binder, a solvent, a plasticizer, etc. if necessary, and the ceramic powder, organic binder9 solvent, and plasticizer are of the type used to create the green sheet in the first method. Also, the amounts of the organic binder and solvent used for producing the green sheet can be used. Furthermore, the fabric used in the first method can be used as the fabric having conductivity only in a predetermined direction.

One or more pieces of the fabric are buried in the slurry by any method, but with the aim of preventing the conductive fibers from connecting with each other after sintering, a fabric woven with fibers that are not conductive in both directions after sintering is used. It may also be placed between conductive fabrics.Then, the slurry is dried and smoked.

After forming a green body containing fabric, it is removed from the mold. An upper layer 1j l of the obtained green body is then crimped.

What are the conditions for crimping? In the first method, conditions 1 to 1 can be used. Next, degreasing as in the first method 1.

Degreased using sintering method. Sintering can be carried out 1-j.

By using the method of the present invention, an anisotropically conductive ceramic composite having an arbitrary thickness and a high conductive density can be easily produced.

In addition, fabrics that have conductivity only in a predetermined direction after sintering, fibers that are made of a resistor with a relatively large resistivity (-), and fibers that disappear after sintering or become non-conductive (7+) are woven. Fibers obtained in can also be used.

(Function) By using a fabric that is conductive only in a predetermined direction after sintering, it is possible to reliably insert a conductor that is conductive in a predetermined direction into an insulating ceramic without the need to form a bag in a predetermined shape as in the past. It can also form the fiber diameter of the fabric. By changing the spacing etc., the conductive density of the composite can also be changed arbitrarily.

(Example) Next, nine detailed explanations of the present invention will be given. In addition, below, "1 part" means "part by weight."

Example 1 30 parts of alumina powder with an average particle size of 2 mm, B with an average particle size of 3 mm
70 parts of an S+0a-B20a-Can glass frit powder, 12 parts of polyvinibutyral, 1-4.8i1ffi of dibutyl fucury, 24 parts of luene, 18 parts of methyl ethyl ketone, and 18 parts of isopropyl alcohol were fed into an alumina ball mill for 3 hours. A slurry was obtained by kneading I-.

The obtained slurry was supplied to a doctor blade type green sheet making machine, coated on a polyethylene terephthalate film and dried to form a sheet with a thickness of 200 is and a length and width of 100 x.
A 150 mm green sheet was obtained.

On the other hand, a conductive fiber and a nickel thin wire (φ10 (ba)
), and nylon fiber (φ200
) J■) by knitting both η′9 fibers.
A knitted fabric having conductivity in only one direction was obtained.

The green sheets and the fabric were cut into 5 (1") widths, and each sheet was laminated with 220 sheets, then 1
Pressing was carried out for 10 minutes at 60° C. and 100 kgf/eat to obtain a laminate of 50×50×5Il]IiI.

The straw layered body was supplied to a heating furnace in an air atmosphere, and a heating rate of 1.5t/
Degrease by holding at 500 t for 2 hours.

Next, the temperature was raised at 100°C/11r and sintered at 700°C for 2 hours to obtain an anisotropically conductive ceramic composite.

Two walls perpendicular to the conduction direction of the obtained anisotropically conductive ceramic composite were polished, and then the specific resistance in the conduction direction was measured at three points using a high resistance measuring device. The average of the measurement results was 1°6×10″Ωcm.Also.

The specific resistance in the direction in which the nylon fibers were present was measured at three points.

The average of the measurement results was 6.8×10'4.

Example 2 Inconel heat-resistant alloy thin wire (φ100
By using nylon fibers (φ200 diameter) as fibers that extend in the direction perpendicular to the conductive fibers and are burnt out after sintering, the fabric is conductive in only one direction. Obtained textiles.

The green sheet and the fabric obtained in the same manner as in Example 1 were cut into a width of 50 x 5, and each sheet was cut into 2 pieces.
Laminated 20 sheets, then 160℃, 101001c/
cn! Press for 10 minutes under the conditions of 50X50X5mm
A laminate was obtained.

The laminate was degreased and sintered in the same manner as in Example 1 to obtain an anisotropically conductive ceramic composite.

Polish the two walls perpendicular to the conduction direction of the obtained anisotropically conductive ceramic composite, and then measure the specific resistance in the conduction direction at three points using a high-resistance measuring device.1-3The average of the measurement results is It was 1.4X 10-'ΩCI++. Furthermore, in the presence of nylon fibers, the specific resistance in one direction was measured at three points. The average of the measurement results is 6. IX 10”.

Example 3 30 parts of alumina powder with an average particle size of 2 noura, average particle size of 3 μm
Ban-3i02-82[]]3-Ca1lBaO-
70 parts of SiOa glass frit powder 12 parts of polyvinyl butyral. 498 parts of dibutyl phthalate, 30 parts of toluene, and 30 parts of butanol were supplied to an alumina ball mill and kneaded for 3 hours to obtain a slurry.

A woven fabric having conductivity in only one direction obtained in the same manner as in Example 1 was made into a 50×1. After cutting to a width of 0mm,
5Qx iox 3 mm 117) Seven layers were laminated in the cavity of a vacuum injection molding mold. The inside of the mold in which the fabric is laminated is heated to 0. After reducing the pressure to ITorr, the slurry was sucked into the mold to fill the void, and then only the L part was removed.

A molded product was obtained by dry smoke I2.

The above process was repeated to produce 10 molded bodies, and 1
160℃, 100kgf/c after laminating 0 molded bodies
n! Press for 10 minutes under the conditions of 50X IOX 2
A laminate of 0+[1[+1] was obtained.

The molded body was degreased and sintered in the same manner as in Example IL to obtain an anisotropically conductive ceramic composite.

Two walls perpendicular to the conductive direction of the obtained anisotropically conductive ceramic composite were polished (2°), and then the specific resistance in the conductive direction was measured at three points with a high resistance measuring device (-).The average of the measurement results was 1.5xlO-'Ωcm. Also, the specific resistance in the direction in which the nylon fiber existed was measured at one point.The average of the measurement results was 7.7x10"1""t), 1゜Example 4 The slurry obtained in the same manner as in Example 3 was mixed with 51)×1
Filled into a 083 mm mold (after that, J- was obtained in the same manner as in Example 1. After cutting the fabric having conductivity in only one direction to a width of 50 x 10 ffllll,
Seven pieces were buried in a mold filled with the slurry and dried to obtain a molded article.

Repeat the above process to create 10 molded bodies,
After laminating 10 molded bodies] 60℃, 100kgf
/eIIi condition for 10 minutes, 50X I
Obtain a laminate of OX 20a+m.

Two walls perpendicular to the conduction direction of the obtained anisotropic conductive ceramic composite were polished, and then the specific resistance in the conduction direction was measured at three points using a high resistance measuring device.1. Ta. The average of the measurement results is 1
．． It was 7×10-'Ωcm. Further, the specific resistance in the direction in which the nylon fibers were present was measured at three points. The average of the measurement results was 7.0×10”.

(Effects of the invention) The present invention has the following features. 1-2. Forming a woven fabric having conductivity only in a predetermined direction into a green body mainly composed of paramix powder (insulating) 1-2. Since the conductor is then sintered in an air atmosphere, the conductor can be easily buried in the insulating material (-), which eliminates the need for the process of forming a conductive pattern as in conventional methods. Anisotropically conductive ceramic composites can be obtained.

[Brief explanation of the drawing]

FIGS. 1 and 2 are perspective views schematically showing one step of the method of the present invention. DESCRIPTION OF SYMBOLS 1... Green sheet, 2... Fabric that has conductivity only in a predetermined direction after sintering, 3... Laminated body. that's all

Claims (1)

[Claims] 1. A plurality of green sheets mainly composed of insulating ceramic powder and a woven fabric that is conductive only in a predetermined direction after sintering are laminated and pressed together, and then sintered in an air atmosphere. A method for producing an anisotropically conductive ceramic composite comprising: 2. After sintering, one or more fabrics that are conductive only in a predetermined direction are laminated in a mold with voids, and then the voids of the mold are filled with a slurry containing insulating ceramic powder as the main component. A method for producing an anisotropically conductive ceramic composite, which comprises making a green body including a woven fabric, laminating and pressing one or more of the green bodies, and sintering the green body in an air atmosphere. 3. bury one or more fabrics that are conductive only in a predetermined direction after sintering in a slurry containing insulating ceramic powder as a main component to create a green body containing the fabric; A method for producing an anisotropically conductive ceramic composite, characterized by laminating, pressing, and sintering in an air atmosphere.