JPH0971475A - Production of ceramic substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the occurrence of defectives caused by unevenness of heating without deteriorating the productivity when baking a stack of green sheets in a heating and baking furnace at high temperatures and providing a ceramic substrate. SOLUTION: A stack 2 of green sheets is housed in each box unit 1 having the opened top surface and one opened side and the plural box units are stacked on the top surface of a bed plate 3 with the openings of one side properly arranged in the same direction. Furthermore, plural other box units 1' housing the stacks of the green sheets are stacked so as to face the opening on one side thereof to the openings on one side of the previously stacked box units 1. The box units in this state are then fed into a heating and baking furnace.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a ceramic substrate used for a chip resistor, a thermal print head, a hybrid integrated circuit or the like.

[0002]

2. Description of the Related Art In general, a ceramic substrate of this kind is still a soft green sheet, and a break groove for breaking the ceramic substrate into small substrate pieces on either or both of the front surface and the back surface thereof. Carving, then stacking a plurality of them in a laminated form, placing this green sheet laminate on a transfer means such as a belt conveyor, and sending it to a heating and firing furnace, and first, for example, about 100
It is manufactured by heating to a temperature of ˜500 ° C. for degreasing treatment, and then firing at a high temperature of, for example, about 1500˜1600 ° C.

In the prior art, when firing the green sheet laminate, a plurality of the green sheet laminates are placed on the upper surface of the base plate in order to improve productivity, and a plurality of the base plates are attached. The sheets are stacked in a plurality of stages with a block for spacing therebetween being sandwiched and fed into the heating and firing furnace in this state.

[0004]

However, in the above-mentioned conventional method, since the surface of each green sheet laminate placed on the upper surface of each base plate is directly exposed in the heating and firing furnace, each green sheet is exposed. Since it is not possible to heat the sheet laminate equally in each place, uneven heating is likely to occur, and in the portion that is heated strongly, it will shrink more than in the portion that is weakly heated, and each ceramic substrate will have an irregular shape. From
There was a problem that the incidence of defective products was high.

It is a technical object of the present invention to provide a method capable of reliably reducing the rate of occurrence of defective products during firing at high temperatures without lowering productivity. is there.

[0006]

In order to achieve this technical object, the present invention provides: "A plurality of clean sheets are stacked in a stack, and the green sheet laminate is sent to a heating and firing furnace by a transfer means; In the method for manufacturing a ceramic substrate that is fired at a high temperature, the green sheet laminate is housed in a box body formed so that an upper surface and one side surface are open, and the green sheet laminate box body is housed. On the upper surface of the base plate, the open portion on one side surface of each box body in one row and the open portion on one side surface of each box body in the other row face each other in a multi-tiered manner in two rows. It is characterized in that they are piled up so that they fit together, and in this state, they are sent to the heating and firing furnace. ”

[0007]

[Operation] By doing in this way, the open portion on the upper surface of each of the box bodies and the open portion on the one side surface can be closed by each of the box bodies. The entire surface of the green sheet laminate can be made to be almost completely surrounded by the box body, and in this state, the green sheet laminate in each box body is indirectly heated through the box body. As compared to the conventional case where the entire surface of the green sheet laminate is directly exposed in the heating and firing furnace as in the conventional case, it is possible to uniformly heat each place, and it is possible to ensure that heating unevenness occurs. It can be reduced to

In order to indirectly heat the green sheet laminate by accommodating the green sheet laminate in the box body, it is preferable that the box body is constructed so that only its upper surface is opened. However, when the box body is configured with only the upper surface open,
Inserting the green sheet laminate into the box body,
Also, it is necessary to take out after firing from the open part of the upper surface while sandwiching it from the left and right sides, so at this time, the green sheet may be deformed or the ceramic substrate after firing may be cracked or damaged. Is likely to occur, and it is necessary to provide a fairly large gap between the outer peripheral surface of the laminate and the inner surface of the box body so that a clamp body for sandwiching the laminate can be inserted. In other words, since the box body has to be considerably larger than the green sheet laminate, the number of green sheet laminates that can be sent to the heating and firing furnace per unit time is Since the box body for accommodating the sheet laminate becomes smaller, the productivity of the ceramic substrate is lowered.

On the other hand, according to the present invention, each box body is configured to open one side surface in addition to opening the top surface as described above. Since the sheet laminate can be inserted and taken out after firing by sliding laterally from the opening portion on one side surface of the box body, a green sheet can be inserted and taken out from the box body. It is possible to reliably reduce the deformation of the sheet and crack damage to the ceramic substrate after firing, and also to reduce the gap between the outer peripheral surface of the laminate and the inner surface of the box body to reduce the size of the box body. It can be realized.

[0010]

Therefore, according to the present invention, By indirectly heating the green sheet laminate in a state of being housed in the box body, it is possible to reduce heating unevenness that occurs during heating, and thus it is possible to reliably reduce the occurrence rate of defective products having an irregular shape. . By allowing the stacked body to be put in and taken out of the box body from the opening portion on one side surface of the box body, it is possible to surely reduce damage to the stacked body at the time of putting in and take out the box body, and to reduce the size of the box body. It is possible to prevent a decrease in productivity. Has the effect of saying.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. First, as shown in FIGS. 1 to 3, a box body 1 formed of a heat-resistant material so as to open an upper surface and one side surface is prepared, and a plurality of green sheets are provided in the box body 1. A green sheet laminate 2 formed by stacking the above is stored.

Next, as shown in FIG. 4, a plurality of box bodies 1 containing the green sheet laminate 2 are opened on the upper surface of the base plate (or pallet) 3 on one side surface of each box body 1. Parts are aligned in the same direction and stacked in multiple stages. Further, a lid plate 4 made of a heat resistant material is placed on the upper surface of the box body 1 at the uppermost stage. In addition, on the upper surfaces of the three side surfaces of each box body 1, there are recesses 1 for distributing hot air.
a is provided.

On the other hand, a portion of the upper surface of the base plate (or pallet) 3 near the stacked box bodies 1 is made of a heat resistant material similar to the box body 1 as shown in FIGS. 5 and 6. A plurality of other box bodies 1'formed to open the upper surface and one side surface and accommodating the green sheet laminates 2, and the opening portions on the one side surface of each of the other box bodies 1 are formed. Align in the same direction and stack in multiple stages. At this time, each of the separate boxes 1'is stacked in multiple stages such that the open portion on one side surface faces the open portion on the one side surface of each box body 1 that was previously stacked first, and then the uppermost one of them is stacked. A cover plate 4'made of a heat-resistant material is placed on the upper surface of the box body 1'in the upper stage.

As in the case of the box body 1, recesses 1a 'are provided on the upper surfaces of the three side surfaces of each of the different box bodies 1', as in the case of the box body 1 '. in this way,
On the upper surface of the base plate 2, a plurality of box bodies 1 containing the green sheet laminate 2 and a plurality of other box bodies 1 ′ also containing the green sheet laminate 2 are placed on the upper surface of the base plate 1. After stacking in two rows of multi-stages so that the open portions on one side face of one side face each other, a cover plate 4'made of a heat-resistant material is placed on the upper surface of the box body 1'in the uppermost stage. By arranging the box bodies 1 and 1 ′, the open portion on the upper surface and the open portion on one side surface of each of the box bodies 1 and 1 ′ can be closed to each other, so that the green housed in the box bodies 1 and 1 ′ can be closed. The entire surface of the sheet laminate 2 may be surrounded by the box bodies 1 and 1 '.

Therefore, in this state, the green sheet laminate 2 is fed into the heating and firing furnace together with the base plate 2 by a transfer means such as a belt conveyor so that the entire surface of each green sheet laminate 2 is a box body 1. In the state surrounded by 1 ', since it is indirectly heated via the box bodies 1 and 1', the entire surface of the green sheet laminate is directly exposed in the heating and firing furnace as in the conventional case. As compared with the case where the heating is performed, the heating can be performed equally at each place, and the occurrence of uneven heating can be reliably reduced.

The green sheet laminate 2 is inserted into each of the box bodies 1 and 1'and taken out after firing, by sliding the green sheet laminate 2 laterally from the opening on one side surface of the box body 1,1 '. To do so.

[Brief description of drawings]

FIG. 1 is a perspective view of a box body used in an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a perspective view showing a state in which the box bodies are stacked on a top surface of a base plate in a multi-step manner.

FIG. 5 is a perspective view showing a state in which the box bodies are stacked in two rows on a top surface of a base plate.

6 is a vertical front view of FIG.

[Explanation of symbols]

 1,1 'Box body 2 Green sheet laminate 3 Base plate 4,4' Lid plate

Claims (1)

[Claims] 1. A method for producing a ceramic substrate, comprising stacking a plurality of green sheets in a laminated form, feeding the green sheet laminate to a heating and firing furnace by a transfer means, and firing at a high temperature. The sheet laminated body is housed in a box body formed so that the upper surface and one side surface are opened, and a plurality of the box bodies containing the green sheet laminated body are arranged in two rows in a multi-stage manner on the upper surface of the base plate. , The open portion on one side surface of each box body in one row and the open portion on one side surface of each box body in the other row are stacked so as to face each other, and in this state, they are sent to the heating and firing furnace. A method of manufacturing a ceramic substrate, comprising: