JPH03193653A - Method for calcining glazed pottery - Google Patents

Abstract

PURPOSE:To prevent the reduction of the commodity value of glazed pottery by putting the glazed pottery with glaze stuck to the under or lateral surface on a shelf so that the glazed surface is brought into contact with a specified sheet, firing the pottery, causing expansion between the glaze and sheet and separating the fired pottery after cooling. CONSTITUTION:Glazed pottery 3 with glaze 4 stuck to the under or lateral surface is put on a shelf 1 so that the glazed surface is brought into contact with the SiC or Si3N4 sheet 2, the top of the pottery 3 is held by a comblike holder 5 as required and the pottery 3 is fired. LiCO3 or boric anhydride in the glaze 4 is allowed to react with the SiC or Si3N4 to cause expansion and the fired pottery is separated after cooling by utilizing the expanded part.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for firing glazed ceramics such as Noshi tiles, in which glaze is adhered to the lower surface or the lower end of the side surface.

(Prior Art) Shelf boards made of mullite refractories are generally used for firing glazed P4 porcelain such as roof tiles. However, if the glaze surface comes into direct contact with the shelf board, it will weld during firing, so
Conventionally, the following measures were taken.

The first method is to place a layer of clay on the surface of a refractory shelf, place glazed ceramics on top of it, and then fire it. However, since this method uses clay, it is necessary to frequently reapply the clay after each firing.

The second method, as shown in Japanese Utility Model Application Publication No. 54-118452, is to place a jig made of heat-resistant metal, and to support the glazed ceramics on this jig and fire the glazed ceramics. A third method, as shown in Japanese Utility Model Publication No. 60-27920, is to place a round rod made of heat-resistant metal on a shelf board, support the glazed ceramics thereon, and fire the glazed ceramics. However, in both methods, the lifespan of the heat-resistant metal is short and it is necessary to replace it every six months, making it uneconomical.The oxide of the heat-resistant metal tends to adhere to the glazed surface of the tile, reducing the commercial value. In particular, in the case of the third method, there were problems such as the round bar being prone to bending during firing and requiring frequent correction.

(Problems to be Solved by the Invention) The present invention solves these conventional problems and corrects jigs, etc. for glazed ceramics, such as roof tiles, in which the glaze is adhered to the lower surface or the lower end of the side surface. This was completed in order to provide a method for firing glazed ceramics that can be fired economically without requiring any additional labor and without reducing the commercial value of tiles.

(Means for Solving the Problem) The above problem is achieved by placing glazed ceramics with glaze attached to the lower or side surfaces on a shelf board made of SiC or Si3N4 so that the glazed surface is in contact with the shelf board. This problem can be solved by a method for firing glazed ceramics, which is characterized by firing, foaming between the glaze and SiC or Si3Nn, and peeling off using the foamed part after cooling.

(Example) The present invention will be explained in detail below along with illustrated embodiments.

In the first embodiment shown in FIG. 1, (1) is a shelf board made of mullite refractory, and (2) is a floor board made of SiC that is placed on the surface and constitutes a tile support part. (3) is a glazed ceramic such as a roof tile that has the glaze (4) adhered to the bottom surface, and is arranged so that the glazed surface is in direct contact with the SiC floor plate (2), and if necessary, Firing is performed with the upper end supported by a comb-shaped holder (5).

In the second embodiment shown in FIG. 2, the entire shelf board (1) is S
It is composed of i3Nn.

When fired in this way, the lithium carbonate and boric anhydride in the glaze (4) become
Or it reacts with Si+N4 to produce foaming. For this reason,
When the glazed ceramic (3) is lifted from the fence plate (1) after being cooled after firing, it is easily peeled off from the foamed portion, and welding as in the conventional case does not occur. Although marks remain on the peeled parts, most of the parts are covered with gas due to foaming, and the actual adhesion area is very small. It should be such that there is no risk of damage.

In the third embodiment shown in FIG. 3, SiC round rods (6) are placed on both sides of the upper surface of a shelf board (1) made of mullite refractories.
(6) is placed, and the glazed ceramics (3) are placed on top of it so that the glazed surface is in contact with the round bar (6), and firing is performed.

Further, in the fourth embodiment shown in FIG. 4, a support rod (7) made of SiC and having a triangular cross section is used in place of the round rod (6). Moreover, this support rod (7) may have a rectangular shape or the like. Furthermore, the number of these support rods (7) may be three.

In the third and fourth embodiments as well, foaming occurs between the glaze (4) of the glazed ceramics (3) such as roof tiles and the round rod (6) or support rod (7), resulting in the above-mentioned problems. Similarly, it can be easily peeled off. For this reason, unlike conventional stainless steel tile support rods, there is no need to avoid installing the glazed surface of the glazed ceramics (3), and it is possible to support the parts close to both ends of the glazed ceramics (3). Stability can be further improved.

Furthermore, as in the embodiment shown in FIG. 5, three rod-shaped projections (8
), it is also possible to make glazed ceramics (3) such as roof tiles free-standing without using the comb-shaped holders (5). In this case, it is effective to move the central rod-shaped projection (8) toward either the left or right direction in order to prevent the glazed ceramics (3) from collapsing.

Furthermore, as shown in Fig. 6, there are two rod-shaped protrusions (8),
A toothed holder (5) can also be used to support the glazed porcelain (3).

(Effects of the Invention) As described above, according to the present invention, at least the supporting portion is made of Si.
Since the glazed surface of the glazed ceramics is brought into direct contact with the shelf board made of C or 5isNa for firing, the following effects are produced.

■According to the present invention, there is no need to use heat-resistant metal jigs or round bars as in the past, and even when using SiC or 5i3Nn round bars as in the third and fourth embodiments. Since these can be used semi-permanently, glazed ceramics can be fired much more economically than before.

■According to the present invention, the round bar does not bend as in the past, and there is no need for troublesome maintenance such as frequent correction.

- According to the present invention, oxides of heat-resistant metals do not adhere to glazed ceramics and impair their commercial value, unlike in the past.

■According to the present invention, it is not necessary to support the tile avoiding the glazed surface of glazed ceramics as in the past, so stability can be improved.

Therefore, the present invention greatly contributes to the development of industry as a method for firing glazed ceramics such as roof tiles that solves the problems of the conventional methods.

[Brief explanation of drawings]

FIG. 1 is a perspective view illustrating the first embodiment of the present invention;
The figure is a perspective view for explaining the second embodiment, FIG. 3 is a perspective view for explaining the third embodiment, FIG. 4 is a perspective view for explaining the fourth embodiment, and FIG. 5 is a perspective view for explaining the fifth embodiment. FIG. 6 is a front view showing the sixth embodiment. (1): Shelf board, (2): Floor board, (3): Glazed ceramics, (
4): Glaze, (6): Round rod, (7): Support rod. Figure Figure Figure 4 Figure Figure

Claims (1)

[Claims] 1. Glazed ceramics with glaze attached to the bottom or side surfaces,
The glaze is placed on a shelf made of SiC or Si_3N_4 so that the glaze surface is in contact with the shelf and fired, and the glaze and SiC
Or, a method for firing glazed ceramics, characterized by foaming between Si_3N_4 and peeling using the foamed part after cooling. 2. The method for firing glazed ceramics according to claim 1, wherein only the support portion is made of SiC or Si_3N_4.