JPS6025397B2 - Method for manufacturing glazed ceramic substrate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a so-called glazed ceramic substrate in which a ceramic substrate is coated with glass, and is intended to provide a glazed ceramic substrate with high surface flatness.

Glazed ceramics, which are ceramic substrates coated with glass, have come to be widely used as substrates for electric circuits such as integrated circuit boards and thermal head (thermal printing parts of thermal printers, etc.) substrates.

The electric circuit described above is produced by forming a thin film on a glazed ceramic substrate by vacuum evaporation, sputtering, etc.
It is formed by patterning it using photolithography or the like, and the glazed ceramic substrate is required to have high flatness. There are spray methods, roller methods, transfer methods, sedimentation methods, etc. as methods for coating glass on ceramic substrates, but the present invention uses screen printing, which is superior in terms of efficiency but lacks sufficient flatness. This makes it possible to manufacture glazed ceramic substrates with high productivity, and also significantly improves the reduction in flatness due to foaming, which was a common drawback of conventional methods.

That is, the method for manufacturing a glazed ceramic substrate of the present invention involves screen printing a paste-formed glass frit onto a ceramic substrate, then firing it, and printing the paste-formed glass frit again on the glass surface of the fired ceramic substrate. It is characterized in that it is then fired. The present inventors have conducted intensive research on glass coatings formed on ceramic substrates by screen printing,
The present invention was completed by obtaining the following knowledge.

That is, when coating glass on a ceramic substrate by screen printing, glass having the desired physical properties is first fritted, a kneading agent, a viscosity modifier, etc. are added to it to form a paste, and then it is screen printed on the ceramic substrate. However, if screen printing is performed only once, the glass and ceramic will react during the subsequent firing process and surface irregularities will occur, making it impossible to create a glazed ceramic substrate that can be put to practical use. When cooled, the surface irregularities caused by the reaction are corrected,
improved, resulting in very good surface flatness. The composition of the glass coated on the ceramic substrate is conventional S.
Although it may be of the i02-Pb○ series, Sj0250-60% by weight and AI20310-30 developed by the present inventors
Weight%, Ca○10 Mg015~30 Weight, Zr022~
6% by weight as main components, and Ti02, B20, Z
n0, PO0, P205, B203, Na20, K20
If one or more of these are used as a substitute for a part of the above main components or simply added, if necessary, the heat resistance and chemical resistance will be more effectively improved.

As the ceramic substrate, appropriate materials such as alumina, beryllia, magnesia, steatite, forsterite, and zirconia substrates can be used. The feature of the present invention is that after screen-printing a paste-formed glass frit on a ceramic substrate, it is heated and fired, and after cooling, the above-mentioned paste-formed glass frit is screen-printed again on top of it, and then heated and fired. be.

In this way, it is possible to eliminate the drawback of the conventional technology that surface irregularities occur due to foaming caused by the reaction between glass and ceramic, and to make the surface smooth. In other words, when manufacturing glazed ceramics, gas components such as bubbles contained in the glass during the manufacturing process of glass frit, or air mixed in during the firing process, may foam during the melting process and form recesses on the glass surface. can be,
This is one of the main deficiencies of the conventional method, but in the present invention, the molten glass layer is formed in two steps.
Each molten glass layer becomes thinner (1'2), and as a result, it is easily defoamed, and even if the first layer is uneven, the
By repairing this with layered coating, etc., the occurrence of defects can be significantly suppressed, which is a great effect. Further, according to the method of the present invention, a glass layer having a high transition temperature can be obtained. Note that when carrying out the present invention, the glass coating may be formed in multiple stages as necessary, and the thickness of the glass coating formed in each stage does not need to be the same, but may be formed as appropriate depending on the conditions. can be changed to

Claims (1)

[Claims] 1. A glazed ceramic product characterized by screen-printing paste-formed glass frit on a ceramic substrate, then firing it, screen-printing paste-formed glass frit again on the glass surface of the fired ceramic substrate, and then firing it. Substrate manufacturing method.