JPS6247185A - Drying of thick film circuit part - 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] [Summary] In the drying process after screen-printing a desired circuit pattern on the surface of a substrate, the width of the circuit pattern is reduced by drying while discharging steam from the heating chamber of the drying oven. Prevent it from expanding.

[Industrial application field]

The present invention relates to a method for manufacturing thick film circuit components, and particularly to an improvement in a drying method.

In manufacturing thick film circuit components, a desired paste-like conductor, resistor, dielectric, etc. is screen printed on the surface of the substrate, placed in a drying oven, and heated at a low temperature (for example, 150℃).
It is common practice to dry the material at a temperature of 0.degree.

[Conventional technology]

FIG. 2 shows a drying characteristic diagram of a thick film circuit component, FIG. 3 is a side sectional view of a conventional drying oven, and FIG. 4 is a partially cutaway perspective view of the thick film circuit component.

As shown in FIG. 4, the thick film circuit component 1 is produced by screen-printing a circuit pattern on the surface of a substrate 2 such as an alumina substrate by pasting a desired paste-like conductor, resistor, dielectric material, etc. It is then dried at a low temperature, then fired at a high temperature, and this process is repeated.

However, in FIG. 4, one type of circuit pattern 3
(The circuit pattern in the figure shows a conductor pattern made of Ag--Pd.) only. The film thickness of circuit pattern 3 is 2
The film width is, for example, 200 μm, and the film interval between adjacent circuit patterns 3 is a desired distance B.

The drying characteristics of the drying process carried out after screen printing this circuit pattern 3 are as shown in FIG.

In Fig. 2, the vertical axis shows the drying temperature, and the horizontal axis shows the drying time. Immediately after putting the thick film circuit component l into the drying oven, a minute (for example, 2 minutes) is the temperature raising step 14A, which is a straight line from normal temperature. The temperature is then raised to a predetermined temperature T'C (for example, 150° C.).

In the heat retention step 15A, the temperature is maintained at T'C for b minutes (for example, 10 minutes), and in the next temperature drop step 16A, the temperature is gradually lowered for 0 minutes (for example, 2 minutes). (I'm making a sea urchin.

In order to dry the thick film circuit component 1 according to the above-mentioned temperature characteristics, conventionally, as shown in FIG. This is done to streamline drying work.

In FIG. 3, an elongated drying oven 10 has an outer wall formed of an oven wall 11, and is provided with a kidney chamber 14, a heat preservation chamber 15, and a cooling chamber 16 from the oven inlet 20 side, and a cooling chamber 16 at the oven outlet 21 side.

The container 5 on which the thick film circuit component 1 is placed is installed so as to run horizontally from the furnace inlet 20 toward the furnace outlet 121 at a desired speed.

At the bottom of the heating chamber 14, there is a heater 17A for lower temperature increase control, and at the upper part, a -L section temperature control heater 1 is installed.
7B, a heat-retaining heater 18 is installed in the insulating room 15, a temperature-lowering heater 19 is installed in the cooling room 16, a partition wall 12 is installed between the greenhouse 14 and the insulating room 15, and a partition wall 12 is installed in the insulating room 15.
A partition wall 13 is provided between the cooling chamber 16 and the cooling chamber 16, and the structure facilitates temperature control.

In such a drying oven 10, the thick circuit component 1 is placed on the conhair 5 and placed in the oven [12o, then put into the drying oven 1o,
The temperature is raised to a predetermined temperature T"C for a minutes in the heating chamber 14, held at T"C for b minutes while passing through the insulating chamber 15, and then sent to the cooling chamber 16, where the temperature is gradually lowered for C minutes. , the thick film circuit component l is dried by removing it at the furnace outlet 21.

[Problem that the invention seeks to solve]

However, in the above-mentioned conventional drying method for thick film circuit components, a large amount of volatile components of the printed paste-like circuit pattern evaporates in the heating chamber. Therefore, by continuously drying the thick film circuit component 1, this vapor fills around the thick film circuit component 1, preventing evaporation, and the paste becomes fluidized due to the high temperature. Therefore, as shown in FIG.
It becomes a.

The width of the circuit pattern 3 is expanded by this protrusion 3a. Furthermore, the distance B between adjacent circuit patterns 3 is reduced to a distance of 0. That is, there is a problem that it becomes difficult to obtain desired characteristics of the thick film enclosure component 1.

[Means for solving problems]

In order to solve the above-mentioned conventional problems, the present invention screen-prints a circuit pattern of a paste-like conductor, resistor, or dielectric material on the surface of a substrate, and then performs a drying process and a baking process to form a thick film circuit component. During manufacturing, as shown in Figure 1,
An air duct 25 is provided in the Jil chamber 1 and 4 of the continuous drying oven 30 to dry the thick film circuit component 1 while discharging the vapor emitted by the paste-like circuit pattern.

[Effect]

According to the means of the present invention, the exhaust duct 25 is provided in the warming chamber 14 of the drying oven 30, and the steam inside the warming chamber 14 is discharged to the outside of the oven, so that the evaporation of the paste-like circuit pattern 3 progresses. Hardening of the circuit pattern 3 is promoted. Therefore, the circuit pattern 3 does not hang down to the periphery, and a predetermined pattern width is maintained.

〔Example〕

The present invention will be specifically explained below with reference to illustrated examples. Note that the same reference numerals indicate the same objects throughout the figures.

FIG. 1 is a sectional side view of a drying oven according to an embodiment of the present invention.

The drying oven 30 shown in FIG. 1 is different from the conventional drying oven 10 shown in FIG. This is what we have set up.

Furthermore, since the steam in the heating chamber 14 is exhausted together with air through the exhaust duct 25, the amount of cold air flowing into the four greenhouses through the furnace inlet 20 increases. Since this cold air makes it difficult to control the temperature of the heating chamber 14, a guide plate 12a is provided near the furnace inlet 20.

Due to the action of the guide plate 12a, the inflowing air from the furnace inlet 20 is detoured along the side wall of the furnace, is preheated, and enters the heating chamber 14. Therefore, the ambient temperature of the thick film circuit component 1 can be easily controlled.

As described above, the exhaust duct 25 is installed in the heating chamber 14.

By drying the thick film circuit component 1 while discharging the vapor evaporated from the printed paste-like circuit pattern, the area around the thick film circuit component 1 is always maintained in an unsaturated state.

Therefore, the evaporation of the evaporative components of the paste progresses, and the curing of the circuit pattern 3 is promoted, so that the circuit pattern 3 does not sag around the periphery, and a predetermined pattern width can be maintained.

〔Effect of the invention〕

As explained below, the present invention allows the printed paste-like circuit pattern to be dried while exhausting the steam in the heating chamber of the drying oven, thereby preventing the peripheral edges of the circuit pattern from sagging and forming the circuit. This has excellent practical effects in that the pattern can maintain a predetermined width and desired characteristics of thick film circuit components can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view of a drying oven according to an embodiment of the present invention, Fig. 2 is a drying characteristic diagram of thick film circuit components, Fig. 3 is a side sectional view of a conventional drying oven, and Fig. 4 is a side sectional view of a drying oven according to an embodiment of the present invention. FIG. 2 is a perspective view of a thick film circuit component. In the figure, 1 is a thick film circuit component, 2 is a board, 3 is a circuit pattern, 5 is a conveyor, 10.30 is a drying oven,
14 is a warming room, 15 is a heating room, 16 is a cooling room, 25 is an exhaust duct, and 26 is an exhaust fan. /6--Kojiken-W-Kan, Droji H-Kenyosu publication rules

Claims (1)

[Claims] In manufacturing a thick film circuit component by screen-printing a circuit pattern of a paste-like conductor, resistor, dielectric, etc. on the surface of a substrate, and going through a drying process and a baking process, the drying process An exhaust duct is provided in the heating chamber (14) of the drying oven (10), and the thick film circuit component (1) is dried while exhausting steam generated from the paste-like circuit pattern. Method for drying thick film circuit components.