JPS5899163A - Manufacture of ceramic substrate - 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] The present invention relates to a method for manufacturing a ceramic substrate.

Conventional ceramic substrates 9 For example, pure alumina [96] ceramic substrates are made by uniformly mixing an inder (an organic material for forming a polyethylene terephthalate sheet) and a plasticizer to impart plasticity to the raw ceramic sheet. A light slip is mixed with an organic swelling agent to form a slurry (hereinafter referred to as slip), and the organic solvent is removed by drying to form a raw ceramic sheet.9 This is then punched into a desired shape, colored, and painted on its surface. It was manufactured by applying mold release powder such as alumina, placing it on plywood and firing it at the required temperature. However, if raw ceramic sheets punched into desired shapes are mounted one by one on plywood, productivity is low and the unit price of the product is high.

To increase productivity, there is a method of stacking several ceramic substrates and firing them, but in this method, the ceramic substrates are fused together during firing. Therefore, in order to prevent fusion, a release powder such as alumina particles is applied to the surface of a raw ceramic sheet before firing. However, if the raw punched ceramic sheet has a complicated shape, it is difficult to apply the mold release powder evenly.If the applied mold release powder is not uniform, multiple raw punched ceramic sheets may be stacked. Therefore, there were drawbacks such as warping of the ceramic substrate after firing. Furthermore, when drying the slip using tape casting to form a raw ceramic sheet, the film is peeled off after drying and only the raw ceramic sheet is rolled up. When these foreign substances adhere, the ceramic substrate after firing is deformed and runs, causing problems such as adhesion of foreign substances.

It is an object of the present invention to provide a method for manufacturing a ceramic substrate free of such drawbacks.

The present invention relates to a method for producing a ceramic substrate, in which raw ceramic sheets are formed on a release powder-containing film by tape casting, and at least two sheets are stacked and fired without peeling off the release powder film.

The ceramic substrate in the present invention includes, for example, an alumina substrate with an alumina purity of 96% or more, but is not particularly limited. Alumina particles are generally used as the release powder, but there are no particular restrictions on the particle size or shape. The releasing powder may be incorporated into the film by uniformly mixing it with the film material to form a film, or by adhering it to two 2-ilms using an adhesive or the like. In any case, even if the film is made of a plurality of films pasted together, there is no restriction at all as long as it can be handled as a single film. Further, the amount of release powder contained in the film is not limited in any way as long as it functions as release powder. The material and thickness of the film are not limited either, and films such as polypropylene, polyester, and polyethylene phthalate are used.

There are no particular restrictions on the firing conditions, and the firing can be performed in an oxidizing, slightly reducing atmosphere, etc., and the firing temperature is not restricted at all as long as it is a temperature at which the ceramic substrate can be sintered.

The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples.

The rest below Table 1 20 times the amount of each of the compositions shown in the first example was blended.

The mixture was placed in a hard porcelain 6t bottom mill with three edges of an alumina goal (diameter 25-φ), and mixed for 100 hours to form a slip.

Separately, a piece of polyester film with a thickness of 25 μm (ffi
K, 8031 parts of alumina particles with a particle size of 5 μm, 20Ji parts of epoxy resin GY280 (manufactured by Ciba Geigy), and 6 parts of Bfi', -monoethylamine 0.61 parts.
The mixture was applied at -0°C to a thickness of 25 μm, and then the 25 μm thick polyester film described above was pasted and rolled into 9 rolls, and then aged at 60°C for 60 hours to semi-cure the epoxy resin. This was made into a release powder-containing film having a thickness of 75 μm.

The above-mentioned slip was coated onto the above-mentioned release powder-containing film using a doctor blade method with a gap of λ1, and then applied at 40°C for 3 hours, 60°C for 30 minutes, 70°C for 30 minutes, 80°C for 30 minutes, and 1 hour.
It was dried at 00° C. for 30 minutes to obtain a raw ceramic ivy sheet with a thickness of 1 sll, which was then rolled up together with a release powder-containing film.

Next, the nucleated ceramic sheet and the release powder-containing film were punched into 50s square pieces, and stacked together with the release powder-containing film, 15 sheets were stacked at room temperature to 300°C.
The temperature will rise in 2 hours.

After holding for 30 minutes, the temperature was raised to 1300°C at 30°C/hour, and further raised to 1600°C at 50°C/hour for 4C.
It was held for 0 minutes and fired to obtain a ceramic substrate.

These 15 ceramic substrates had release powder evenly interposed therein, so that they could be easily peeled off one by one without causing any fusion, and furthermore, the release powder could be easily removed from the ceramic substrates.

Comparative Example The slip described in Example was tape cast on a 75 μm thick polyester film under the same conditions.
After peeling off the polyester film and punching out the raw ceramic sheet, 20 parts by weight of alumina particles with a particle size of 5 μm as release powder, 4 parts by weight of Epicoat 1001 (Shell Co., Ltd.) and A slurry consisting of 76 parts by weight of methyl ethyl ketone was applied by spraying at a rate of 30% by weight at 80°C.
After drying for 1 minute to evaporate the methyl ethyl ketone and adhere mold release powder to the surface of the raw ceramic sheet, 15 of the ceramic sheets were stacked and fired under the same conditions as in the example. In addition, 1 out of 15 sheets had punch residue adhering to it, creating an uneven surface. 0 Partial fusion was able to be peeled off by hitting it with a plastic hammer, but at that time the ceramic substrate The end of the was damaged.

In the present invention, a slip is supplied onto a release powder-containing film, a raw ceramic sheet is formed by tape casting, and then the release powder-containing film and the raw ceramic sheet are integrated without peeling off the release powder-containing film. Since the object is punched into the desired shape, it is possible to prevent foreign matter from adhering to the film containing mold release powder and the raw ceramic sheet due to the static electricity generated when the film is peeled off. Since it is punched out in one piece, it is also possible to prevent punching debris from adhering to it.

Furthermore, since the mold release powder is contained on the film before punching out the raw ceramic sheet, the mold release powder can be applied uniformly, and a ceramic substrate can be manufactured without fusion, warpage, or deformation of the ceramic substrate. be able to.

Claims (1)

[Claims] 1.1 Two raw ceramic sheets were placed on the IiI type powder-containing film by tape casting. At least 2 times without peeling off the release powder-containing film.
A method of manufacturing a ceramic substrate, which involves stacking and firing two or more ceramic substrates.