JPS62105948A - Manufacture of ceramic extrusion formed body and compositiontherefor - 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 producing a two-layer ceramic extrusion molded body, particularly a ceramic molded body for electronic materials, and a molding composition used therein.

(Prior art) The conventional method of manufacturing a ceramic extrusion molded body υ is Ceramic 7
The materials are mixed, calcined, and pulverized to form a non-plastic ceramic powder. A binder is added to this powder to give it plasticity, and then kneaded (mixed by tearing with a roll mill, continuous kneader, etc.) This method is used to produce an element body by extruding it and firing it after extrusion molding. However, this method is particularly useful when manufacturing an element body such as a ceramic sheet for electronic materials where high quality is essential. Water-soluble cellulose derivatives such as methyl cellulose containing methoxy groups are widely used as binders. This is done without any impurities being mixed into the clay.
This is because it increases the second water retention property and provides appropriate plasticity for extrusion molding at a small value. However, these water-soluble cellulose derivatives exhibit a hard jelly-like viscosity because the concentration of the paint-gu dispersion required to make extruded products is as high as 10%, and they cannot be mixed unless thoroughly kneaded. The dissolved cellulose and derivatives were not uniformly dispersed in the ceramic powder, and the added cellulose derivative powder often remained in a hydrated and swollen state.

Usually used binder powder always contains 5% or more of particles with a particle size of 150gm or more, and 300gm or more.
In some cases, it may contain about 400 pm.

When a binder with such a particle size is used for extrusion molding of a ceramic on an ICC substrate for electronic materials, the extruded product contains a considerable amount of binder with a particle size of about 300 to 400 uLm. When this is sintered, it becomes a hole of around 100 lumens, which is useful for preparing an IC board on which a circuit is formed by printing a conductor layer and an insulating layer with a thickness of about 1,107 tons on a sintered board. Therefore, it has been desired to develop a method for adjusting the plate by extrusion molding the plate without voids of at least around 1004 m.

(Structure of the Invention) As a result of careful study in view of this fact, the present inventors discovered that the conventional problems could be solved by specifying the particle size of the binder to be added, leading to the present invention.

That is, the first invention of the present invention relates to a method for producing a ceramic extrusion molded body, characterized in that a water-soluble cellulose derivative having particles with a particle size of 150 gm or more and 1 t% or less is used as a pinter, The second invention relates to an extrusion molding composition used in this method. To explain this in detail below, almost all ceramic materials such as alumina, barium titanate, PZT, zirconia, and zinc fermentation can be used as the ceramic material powder used for unreleased 151. It is most effective to apply the present invention to ceramic substrates for use in ceramic substrates. The particle size of the ceramic powder may vary from about 0.1 to 20 gm, and any particle size of a can be used.

Plasticizers represented by polyethylene glycol, glycerin, propylene glycol, ethylene glycol, l,4-butanediol, etc. are usually used in ceramic/reextrusion molding compositions, but these are not used in the present invention. There is no problem.

Water-soluble cellulose derivatives used for unreleased 1 include methylcellulose, hydroxypropylethylcellulose, hydroxyethylmethylcellulose, hydroxyethylethylcellulose, hydroxypropylcellulose,
Any water-soluble cellulose derivative such as hydroxypropylethyl cellulose, hydroxyethyl cellulose, and ethyl cellulose can be used.

In the uninvention, the particle size of the water-soluble cellulose derivative is
The content of particles with a particle diameter of 150 m or more is defined as 0.5% by weight or less, and the method for measuring this is as follows.

Measurement method: First, take 100 g of a water-soluble cellulose derivative sample, place it in the upper layer of a standard sieve specified in JI 5Za801, and place it in the upper layer of a sieve with mesh 11 in order of fineness, and cover the upper layer of the receiver. After setting the Kansai Kinami Co., Ltd. model 429 rotatable sieve shaker on the lower shelf, the number of shakes was 20.
0 times/min, number of strokes 1561i11/min, swing width 50mm
(7) Shake under the conditions for 30 minutes. The residue on the sieve 1'l is collected using a sieve to 0.1 g, and the % of each standard sieve 1'l kl calculated by the linear equation is taken as a measure of particle size.

Sieve (%) = Residue from sieve (g) / Sample <
100>gX 100 In the present invention, standard sieve 100'+(
The binder is a water-soluble cellulose derivative with a sieve L of 0.5i11J% or less.

If a powdered water-soluble cellulose derivative containing 0.5% or more of particles with a length of 15,071 m or more is used, there will always be 100 gm or more of undispersed cellulose derivative in the extruded product. It goes without saying that the smaller the particle size, the better.0 For example, JIS standard sieve No. 270 ([1 opening 5
If you use a fine powder binder that has less than 0.5% of residual material in the sintered ceramic,
There are substantially no pores larger than ~30 pm, resulting in a ceramic of even higher quality.

However, it is extremely difficult to produce such a fine powder binder, resulting in an expensive binder.

The ceramic extrusion molding composition used in the present invention can be obtained by mixing and kneading the above-mentioned ceramic base raw material powder with water, a water-soluble cellulose derivative having a particle size specified in the present invention, and, if necessary, a plasticizer such as glycerin. It will be done.

The amount of cellulose derivative added is determined by the degree of polymerization of the cellulose derivative itself, J
The optimum value for detection of IX material ceramic powder is determined by the particle size, etc., but it is usually about 3 to 1 part (lffi part) per 1 part of ceramic base material tooz, and the cellulose derivative used has a methoxy group or an ethoxy group. In this case, the solubility of these binders improves at low temperatures, usually below 20"C, and they have the property of being difficult to dissolve at high temperatures, so the temperature of the extrusion molding composition is always below 20"C in each step of mixing, kneading, and extrusion molding. It is desirable to manage it in such a way.

Examples and comparative examples of unreleased Ill will be described below.

Examples 1-3. Comparative Examples 1 to 2 (1) Alumina powder (particle size 2° to 0.0°) was used as process competitive ceramic material No. 1.
5 gm + average particle size 1 yen 2.8 gm), and added IK's methoxy-containing cellulose ether and talc (f average particle size 2.
．． 57° C.m) were mixed in the following proportions to obtain a compound.

Alumina (Kuchikaiko LS20V) 10 ([11
% Talc (Matsuzai Sangyo High Filler) 4 ``Cellulose Ether 6'' (Shin-Etsu Chemical 60SH-4000) Next, add the following glycerin 8 '' Wood
18.5" was mixed.

For N, use a Henschel mixer (for F Tsuki Seisakusho super mixer, jacket cooling, 20℃, 500JIiJ/min)
was used.

■ The above mixture was milled in a three-roll mill (Yodo Seisakusho 4 Sea-IIS).
The mixture was kneaded by cooling the mold jacket at 15°C.

A sheet with a thickness of 1 mm was extruded from the mixed wire using a Takuri Kitayama vacuum extrusion molding machine (Kajiwara Seisakusho TKV-50 jacket cooling 15° C.).

(2) Table 1 shows grains 1 and 1 of methoxy-containing cellulose ether 603H-4000 used as a binder in the mixing process of vacuum extrusion molded sheet production.
1 shows the results of a test conducted on an extruded sheet.

(Note) A is an extruded sheet that has been dried at 100℃ for 8 hours, dyed in a 3% methyl blue/methanol solution, and then immersed in acetone to clean the methyl blue that adhered to the ceramic base material (alumina). .

Observe with a 100x optical Wk mirror, and the sheet surface is 1 mrn.
' This shows the particle size and number of binder particles that are dyed blue due to undispersed or uneven distribution.

B is an extruded sheet heated at 1500°C for 2 hours, and the cross section of the sintered body was observed with an electron microscope at 500x magnification.
It shows the number of pores of uL particle size.

From Table 1, by using a binder containing 0.5% by weight or less of particles with a particle size of 150 μm or less, the undispersed Metrose becomes 1004 μm or less, and an extrusion molded substrate suitable for IC-S board can be obtained. Change.

Claims (1)

[Scope of Claims] 1. A method for producing a ceramic extrusion molded body, characterized in that a water-soluble cellulose derivative containing 0.5% by weight or less of particles with a particle size of 150 μm or more is used as a binder. 2. A ceramic extrusion molding composition comprising, as a binder, a water-soluble cellulose derivative containing 0.5% by weight or less of particles having a particle size of 150 μm or more.