JP2006029611A - Tabular structure, and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tabular structure suitable as a setter for baking providing compatibility between degreasing and surface smoothness of a burned product, and its manufacturing method. <P>SOLUTION: Since a ventilation passage 32 communicated with an outer circumference is formed by protrudedly providing a columnar protrusion 16 on one face of a porous tabular part 12 provided with minute communication pores, a passage for air passing through the tabular part 12 from its another face to a one face side in a thickness direction and reaching the outer circumference via the ventilation passage 32 is formed in the setter 10 for baking. Thereby, despite the flatness of the other face mounted with a sheet like forming body 28, degreasing gas is suitably exhausted, and uniformity of temperature distribution can be enhanced. In other words, compatibility between degreasing and surface smoothness can be provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a porous plate-shaped structure suitable for a setter for firing.

  For example, when manufacturing plate-shaped ceramics, a ceramic raw material powder is formed into a plate shape having a predetermined planar shape and subjected to a firing treatment. According to such a powder sintering technique, it is easy to obtain a dense ceramic or a porous ceramic having a desired porosity, and there is an advantage that the degree of freedom of the shape is high.

  Molding of the plate-shaped molded body is, for example, a powder prepared by mixing an appropriate synthetic resin (that is, a molding binder) in a solvent and a ceramic raw material powder, slurry (slurry), clay, paste, etc. Is used in various methods such as press molding, mud casting, injection molding, extrusion molding, and screen printing. In preparing powders and slurries, a dispersant, a plasticizer, a lubricant, and the like are appropriately used in addition to a molding binder. Many of these are organic substances, and a large amount of organic substances are contained in the molded body. Is included.

  Therefore, when performing the firing treatment on the molded body as described above, for example, after removing or degreasing organic components by evaporating or decomposing at a low temperature up to about 600 (° C.), the raw material is continuously or in a separate process. It is held at a suitable high temperature and sintered. In the degreasing step, first, a high boiling point compound such as a plasticizer is volatilized, and then the polymer compound is thermally decomposed or thermally polymerized. The low molecular weight compound is generally volatilized and disappeared as it is, and the polymer is carbonized after taration and further oxidized at a high temperature to be lost as carbon dioxide gas. Therefore, in order to reliably remove unnecessary organic components from the sintered body and obtain uniform shrinkage, it is necessary for the organic components to escape from the molded body uniformly and quickly.

  As a setter for firing for firing the plate-shaped molded body as described above, there are known ones provided with a large number of mutually independent depressions (that is, recesses) on the placing surface of the fired product (for example, patents). Reference 1, 3, 7 etc.). According to this setter, since the contact area between the fired product and the setter becomes small while keeping the mounting surface of the molded body substantially flat, there is an advantage that they are difficult to adhere even if the firing temperature is high. In addition, there are a plurality of grooves provided on the mounting surface and a through-hole penetrating the back surface on the bottom surface of the groove (see, for example, Patent Document 2). According to this setter, it is said that warpage or the like is unlikely to occur because temperature variation in the molded body during firing is suppressed. In addition, there are some in which a large number of grooves are provided vertically and horizontally on the mounting surface (for example, see Patent Document 4). According to this setter, the decomposition gas generated from the molded body escapes through the groove, so that it is possible to prevent the cracking from occurring in the fired product by sufficiently degassing. Moreover, although it is for baking processing of the glass substrate for PDP, there exist some which provided the through-hole in the flat mounting surface (for example, refer patent document 5 etc.). According to this setter, since the heat capacity becomes small, heating and cooling of the substrate are facilitated. In addition, there are those in which a large number of fine linear through holes are provided on the mounting surface (see, for example, Patent Document 6). According to this setter, it is said that decomposition gas etc. are suitably discharged | emitted through the linear through-hole. Some porous ceramic plates are provided with a large number of through holes penetrating from the mounting surface to the back surface (see, for example, Patent Document 8). According to this setter, since it is lightweight and excellent in air permeability, it is difficult to cause cracks and cracks due to repeated thermal cycles.

Japanese Patent Application Laid-Open No. 11-077982 Japanese Utility Model Publication No. 5-010998 JP-A-9-278517 JP 2003-221281 A JP 2000-304458 A JP 2002-145672 A JP 11-335179 A JP 2002-265281 A

  By the way, when firing the plate-like molded body, generally, it is laminated and put into a firing furnace for the purpose of improving the firing efficiency. One type of lamination is a method in which fine sand particles (laying sand), etc., are laid on the surface of each of the shaped bodies to be laminated, and this shaped sand prevents the shaped bodies from joining to each other. In addition, a space for degreasing is secured between the molded bodies. However, in order to ensure the flatness of the mounting surface of the molded body, it is necessary to uniformly disperse the mesh sand, which takes a lot of labor, and a binder for temporarily fixing the mesh sand is necessary, which also takes time for application. At the same time, the amount of organic matter increases, and the sand is attached to the surface of the fired product, so the surface becomes rough and the work to remove the attached sand is necessary. Since the sand creates a dent on the surface of the fired product, the surface becomes rougher. In addition, when using sand with a large particle diameter to facilitate degreasing and increasing the distance between the sand, the mounting surface is substantially reduced. Further, since the flatness of the fired product is lowered due to the uneven surface, there is a disadvantage that it is impossible to achieve both degreasing and flatness. As a result, as the number of stacked layers is increased, non-uniform warpage and undulation increase, and there is a problem that the number of stacked layers is limited.

  On the other hand, for example, a method of laminating the molded body through the setter of Patent Document 4 in which the decomposition gas discharge performance is improved by providing a groove, the setter of Patent Document 8 made of porous ceramics, or the like is considered. It is done. However, in the former setter, since the groove forms large irregularities on the mounting surface of the molded body, it is impossible to achieve both degreasing and flatness as in the case of using sand. Moreover, in the latter setter, since the mounting surface is substantially flat, the flatness of the fired product is ensured, but since the molded body is sandwiched between the substantially flat setters from both sides, the flow of cracked gas, etc. A path is formed between the surface of the setter and its outer peripheral end surface via the inside thereof. For this reason, the flow resistance from the inner peripheral portion to the outer peripheral end surface is remarkably increased, so that the degreasing property when laminated is insufficient.

  The present invention has been made in the background of the above circumstances, and its purpose is to provide a plate-like structure suitable as a setter for firing that achieves both degreasing and flatness of a fired product and a method for producing the same. There is to do.

  In order to achieve such an object, the gist of the plate-like structure of the first invention is that: (a) a porous plate-like portion having a large number of fine communication holes communicating from one surface to a flat other surface; (B) A predetermined-shaped air passage that communicates from the outer peripheral edge to the inner peripheral portion by projecting on the one surface so that the front end surface is located on one plane parallel to the other surface. A plurality of support portions to be formed.

  The gist of the manufacturing method of the plate-like structure of the second invention is that (a) a sheet forming step of producing a green sheet using a predetermined ceramic raw material, and (b) the green sheet on the one surface Forming a plurality of protrusions using a predetermined ceramic raw material to form a recess having a predetermined shape that communicates from the outer peripheral edge to the inner peripheral portion on one surface thereof; and (c) the plurality of the plurality of protrusions. By firing the green sheet on which the protrusions are formed, a porous plate-like portion having a large number of fine communication holes communicating from the one surface to the other surface is generated from the green sheet, and at the same time, a plurality of them are formed on the one surface. And a firing step of generating a plurality of support portions from the protrusions.

  Further, the gist of the manufacturing method of the plate-like structure according to the third aspect of the invention is that (a) a long hole portion in which one long side is constituted by a straight line and a plurality of portions on the other long side of the long hole portion. By extruding a clay of a predetermined ceramic raw material from a die provided with a plurality of branch holes formed on the tip surface on a straight line parallel to the other long side, A molding step of obtaining a plate-shaped molded body having a plurality of protrusions parallel to each other on one surface of the plate-shaped portion and having a flat other surface; and (b) by firing the plate-shaped molded body, And a firing step of generating a plate-like portion and a plurality of protrusions provided on one surface thereof.

  According to the first aspect of the present invention, since the support portion projects from the one surface of the porous plate-like portion having the fine communication holes, the air passage communicating with the outer peripheral edge is formed. The body is formed with a gas passage that passes through the plate-like portion in the thickness direction from the other surface to the one surface side, and reaches the outer peripheral edge via the air passage. That is, it is possible to obtain a plate-like structure from which gas generated on the other surface side is quickly discharged from the one surface side.

  By the above, for example, if the baking treatment is performed in a state where the plate-like molded body is in close contact with the other flat surface of the plate-like structure, the degreasing gas etc. that has escaped from the molded body permeate the plate-like structure in the thickness direction. Then, it flows on the one surface and is discharged from the outer peripheral edge. Therefore, it is possible to obtain a firing setter capable of suitably discharging the degreasing gas even though the mounting surface of the plate-like molded body is flat. In addition, since a good gas flow state is obtained on the one surface side of the plate-like portion in this way, the uniformity of the temperature distribution is improved.

  Therefore, it is possible to achieve both degreasing and flatness by using a plate-like structure as a setter for firing and sandwiching the plate-like molded body between the other surface and the flat surface of another setter. It becomes. In addition, although the fine communication hole opens on the other surface of the plate-like part, the size thereof depends on the flatness required for the fired product and the degree of softness of the fired product in the process from firing to sintering. If the dimensions are sufficiently small, the flatness of the fired product is not affected at all.

  In addition, tar generated by thermal polymerization on the surface of the plate-shaped molded body is sucked by capillary action into fine through-holes opened on a flat surface, so that no liquid pool is generated and it is easily decomposed on one side. The

  Further, since a plurality of support portions are distributed over the entire surface in order to form the air passage, the plate-like portion is supported by the support portions at both the outer peripheral edge portion and the inner peripheral portion. Therefore, since it is not necessary to increase the thickness of the plate-like portion in order to ensure the mechanical strength and flatness of the plate-like portion, the plate-like portion can be made thinner, and thus the thickness dimension of the entire plate-like structure is reduced. can do. Therefore, when it is used as a setter for firing, there is an advantage that the kiln filling efficiency is increased.

  The other setters may be plate-like structures having the same shape, but may be flat thin plates. In the latter case, a porous material is preferable, but a dense material can also be used.

  According to the second invention, when a green sheet is produced in the sheet forming step, a plurality of protrusions are formed on one surface in the protrusion forming step. A plate-like structure having a plurality of support portions on one surface, that is, the plate-like structure of the first invention is obtained.

  According to the third aspect of the invention, the molded body extruded from the die having the long hole portion and the plurality of branch hole portions has a plurality of protrusions parallel to each other on one surface of the plate-like portion. Therefore, by firing this, a plate-like structure having a plurality of protrusions on one surface of the porous plate-like portion, that is, the plate-like structure of the first invention is obtained.

  Here, preferably, the plate-like structure of the first invention has a first surface parallel and flat to the other surface, and is connected to the tips of the plurality of columns on the second surface on the back surface side. The second plate-shaped portion is provided. In this way, the other surface and the first surface, which are flat and parallel to each other, are provided, and an air passage having a predetermined shape is provided between them. Therefore, since both surfaces of the plate-like structure are configured to be flat, the plate-like molded body can be laminated and fired without requiring any other setter or the like. In addition, since both ends of the support portion are connected to the plate-like portion and the second plate-like portion, respectively, the advantage that the support portion is less likely to be damaged compared to the case where the second plate-like portion is not provided. There is also.

  In the above aspect, the second plate-like portion is preferably a porous body having a large number of fine communication holes communicated from the first surface to the second surface, but may be dense. Absent.

Preferably, in the plate-like structure according to the first aspect of the present invention, a minimum value of a ventilation cross-sectional area between a plane passing through the front end surfaces of the plurality of support portions and one surface of the plate-like portion is 0.004 (mm ² That's it. In this way, since the ventilation cross-sectional area is sufficiently large (that is, the size and density of the support portion are determined as such), when used as a firing setter, the degreasing gas, etc. Is more easily discharged. More preferably, the minimum value of the ventilation cross-sectional area is 0.04 (mm ² ) or more, and more preferably 0.1 (mm ² ) or more.

  Moreover, it is used suitably as a setter for baking for baking a thin plate-shaped ceramic molded object.

  Preferably, in the method for manufacturing a plate-like structure according to the second aspect of the present invention, another green sheet produced in the same manner as the green sheet is formed on the plurality of protrusions after the protrusion forming step. It includes a laminating step of laminating. In this way, by laminating the laminated green sheets, a plate-like structure having flat surfaces that can be brought into close contact with each other when the plate-like molded body is fired can be obtained. .

  Preferably, in the method for manufacturing a plate-like structure according to the third aspect of the invention, the forming step includes a second long hole parallel to the long hole portion and connected to the tips of the plurality of branch hole portions. The clay of the predetermined ceramic raw material is extruded by a die having a portion. In this way, a molded body of a plate-like structure in which flat plate-like portions are joined with protrusions is obtained. By firing this, a plate having the above-mentioned air passages inside and flat on both sides is obtained. A shaped structure is obtained.

  Further, the size and distribution density of the fine communication holes provided in the plate-like portion and the second plate-like portion are appropriately determined in consideration of the balance between air permeability and mechanical strength. That is, if the hole diameter of the fine communication holes is reduced or the distribution density is reduced, high mechanical strength can be obtained, but the air permeability is lowered. In this case, it is desirable to increase the air permeability as much as possible, for example, by thinning the plate-like portion. On the other hand, if the hole diameter is increased or the distribution density is increased, high air permeability is obtained, but the mechanical strength is lowered. In this case, it is desirable to increase the mechanical strength as much as possible, for example, by increasing the thickness of the plate-like portion. The thickness dimension of the plate-like portion is determined according to the area of the other surface, the mechanical strength of the constituent material, and the like, but a range of, for example, about 0.05 to 1 (mm) is preferable.

  Preferably, the plate-like portion and the second plate-like portion are made of various oxide ceramics such as alumina, mullite, zirconia, magnesia, rare earth metal oxide, various metal carbides such as carbon and silicon carbide, carbonized. Boron, borides of various metals, nitrides of various metals such as boron nitride and silicon nitride, refractory metals such as tungsten, molybdenum, platinum and iridium, mixtures, compounds or composites thereof.

  Preferably, the plate-like portion has a porosity of 15 to 50 (%) and an average pore diameter of 0.5 to 10 (μm). When smaller than these lower limits, the effect of promoting tar adsorption and degreasing becomes insufficient. Moreover, when it becomes larger than the upper limit value, the mechanical strength becomes insufficient. More preferably, the porosity is in the range of 30 to 45 (%).

  In addition, although the said fine communicating hole can be formed by the space | gap between the constituent particles of a plate-shaped part, you may perforate | pierce and form in the range which does not impair the flatness of the said other surface. In addition, for the purpose of controlling the communication holes formed by the voids, a pore-forming agent that disappears by thermal decomposition can be added.

  Preferably, the average particle diameter of the constituent particles of the plate-like portion is in the range of 1 to 50 (μm). If it becomes smaller than this lower limit value, it becomes difficult to control the communication holes, and if it becomes larger than the upper limit value, the surface roughness of the plate-like portion becomes rough and the strength also decreases.

  The relationship between the thickness dimension t (mm) of the plate-like portion and the maximum width w (mm) in the direction along the one surface of the gas passage formed on the one surface is w / t ≦ 30. It is preferable. If this ratio is larger than this, the other surface will bend and the mechanical strength of the plate-like portion will be insufficient. More preferably, the value of w / t is 20 or less.

  Preferably, a mutual distance between adjacent ones of the support portions, that is, a width dimension of the air passage is in a range of 0.05 to 2 (mm). If it is smaller than 0.05 (mm), gas flow is inhibited, and if it is larger than 2 (mm), the strength of the support part becomes insufficient and the plate-like part is swelled.

  Preferably, the support portion has an aspect ratio (cross-sectional difference dimension, for example, a ratio of a height dimension to a diameter) of 2 or less. When the aspect ratio exceeds 2, the strength of the support becomes insufficient. Further, the height of the support portion, that is, the height of the air passage is preferably in the range of 0.02 to 1.0 (mm). If it is smaller than 0.02 (mm), gas flow is hindered, and if it exceeds 1.0 (mm), the support part is easily broken.

  In addition, the support portion may have an appropriate shape so that a gas flow path is suitably formed, but as a shape that is intermittent in each direction on one surface, a column shape such as a column shape or a prism shape, A frustum shape such as a truncated cone or a truncated pyramid whose cross-sectional area changes continuously or stepwise in the height direction is preferable. Moreover, as a shape which continues along one direction on one surface, the protrusion which the cross section perpendicular | vertical to the longitudinal direction forms a rectangle, trapezoid, etc. is suitable. Moreover, in any case, it is preferable to be provided at a constant center interval along one direction. Preferably, the support portion is integrally projected on the one surface.

  Further, the support portion may be porous like the plate-like portion, but since it does not function as a gas passage, it is configured densely so that the mechanical strength is as high as possible. It is preferable to do.

  The support portion can be made of a material different from that of the plate-like portion. However, the support portion can be made of the same or the same material in order to minimize the stress caused by the difference in thermal expansion. preferable.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the following embodiments, the drawings are appropriately simplified or modified, and the dimensional ratios, shapes, and the like of the respective parts are not necessarily drawn accurately.

  FIG. 1 is a diagram showing an entire firing setter 10 which is an example of a plate-like structure of the present invention. The firing setter 10 is made of alumina, for example, and includes a plate-like portion 12 and a large number of columnar protrusions 16 protruding from one surface 14 thereof. In this embodiment, the columnar protrusion 16 corresponds to a support portion.

  The plate-like portion 12 is, for example, a rectangular thin plate having a thickness of about 0.2 (mm) and a size of about 60 × 80 (mm). For example, as schematically shown in FIG. 2 with the cross-section enlarged, the plate-like portion 12 is obtained by sintering the constituent particles 18 with a gap between them. A large number of fine communication holes 22 communicating with the back surface, that is, the other surface 20 are provided. Therefore, the plate-like portion 12 is a porous body having a porosity of about 35 (%), for example, and the average pore diameter is about 1.9 (μm), but the other surface 20 is substantially smooth and flat. In FIG. 1, the thickness dimension, the size of the columnar protrusions 16, the pitch, and the like are exaggerated with respect to the vertical and horizontal dimensions of the plate-like portion 12, and the gap is exaggerated in FIG. 2. Yes.

  The columnar protrusions 16 have, for example, a cylindrical shape having a diameter of about 0.5 (mm) and a height of about 0.1 (mm), and are provided in a grid pattern along the edge of the plate-like portion 12. It has been. The center interval between the columnar protrusions 16 is, for example, about 1.0 (mm) in both the vertical and horizontal directions. The porosity of the columnar protrusions 16 is substantially 0 (%), and the columnar protrusions 16 are densely configured. Note that the columnar protrusion 16 has a tip surface 24 located on a plane parallel to the surface 14. As is clear from the above numerical values, the porosity in the space where the columnar protrusions 16 are formed is, for example, about 78 (%).

  The firing setter 10 is manufactured, for example, according to the steps shown in FIG. In FIG. 3, in a sheet forming step P1, a green sheet is formed by a sheet casting method using a separately prepared slurry. The thickness of the green sheet was set in two ways so that the thickness after firing would be about 0.2 (mm) and 0.3 (mm) in consideration of firing shrinkage. Hereinafter, the former is referred to as green sheet A and the latter is referred to as green sheet B. As will be apparent from the following description, the green sheet B does not constitute the firing setter 10 but is used at the same time. The slurry is, for example, 100 parts by weight of alumina powder having an average particle size of about 7 (μm), 5 parts by weight of alumina powder having an average particle size of about 0.2 (μm), and 1 part by weight of talc. The mixed powder and, for example, a polyacrylate binder are dispersed in, for example, an alcohol solvent, and the viscosity is adjusted to about 4 (Pa · s), for example.

  Next, in the firing step P2, the green sheets A and B are fired at a temperature of about 1630 (° C.), for example. As a result, the organic components of the green sheets A and B are burned off and the alumina particles and the like are sintered, and a porous flat alumina plate is obtained from each. That is, the porous alumina plate A constituting the porous plate-like portion 12 and the porous alumina plate B constituting the second setter 30 described later having the same configuration except for the thickness dimension are obtained.

  Next, in the protrusion forming step P3, columnar protrusions are thick-screen printed on the surface of the porous alumina plate A using a separately prepared printing ink. Each columnar protrusion has a cylindrical shape with a diameter of about 0.5 (mm) and a height of about 0.1 (mm) (both values after firing), and 1.0 along each of the vertical and horizontal sides of the rectangular porous alumina plate A. They were provided in a grid-like arrangement with a center interval of about (mm). The number of times of printing lamination was set to 5 times, for example. The printing ink is, for example, a mixture of 99 (wt%) alumina powder having an average particle size of about 0.3 (μm) and silica, magnesia, and calcia powder total 1 (wt%) as sintering aids. The mixed powder and the ethyl cellulose binder are dispersed in, for example, a butyl carbitol acetate solvent and prepared to have a viscosity of, for example, about 200 (Pa · s).

  Next, in the firing step P4, the protrusion provided on the porous alumina plate A is fired at a temperature of about 1580 (° C.), for example, lower than the firing temperature of the porous alumina plate A. As a result, the organic components of the protrusions are burned off and the alumina particles and the like are sintered, so that the firing setter 10 in which the dense columnar protrusions 16 protrude on the porous plate-like portion 12 is obtained. . The firing temperature is set to a temperature lower than the firing temperature of the porous alumina plate A so that deformation of the porous alumina plate A, reaction with the projection composition, and the like do not occur.

  FIG. 4 is a cross-sectional view illustrating an example of a usage state of the firing setter 10 described above. The setter 10 for baking is arrange | positioned on the baseplate 26 of a baking furnace, for example so that the front end surface 24 of the columnar protrusion 16 faces a lower side. On the other surface 20 of the setter 10 for firing, a sheet-like molded body 28 that is a fired product is placed. On the sheet-like molded body 28, a second setter 30 is further placed. The second setter 30 is produced from the green sheet B as described above, and is a flat porous plate having a thickness dimension of about 0.3 (mm). On the base plate 26, the fired product is placed, for example, in a three-stage stack, with the setter 10 for firing, the sheet-like molded body 28, and the second setter 30 as a set. Therefore, a space having a height equal to the height dimension of the columnar protrusion 16, that is, the air passage 32, is formed between the base plate 26 and the firing setter 10 and between the second setter 30 and the firing setter 10. ing. The firing setter 10 and the second setter 30 may be upside down.

  When firing is performed in this manner, the tar generated on the surface of the sheet-like molded body 28 by heating is sucked by the capillarity into the setters 10 and 30 in contact with the surface, so that a liquid pool is formed between them. Does not occur. Further, the tar that has entered the continuous air holes 22 oozes out into the air passage 32 and is easily decomposed in the wide space. Further, gas components generated from the sheet-like molded body 28 also flow into the ventilation path 32 through the continuous ventilation hole 22. Therefore, all of the decomposition gas and the like generated from the sheet-like molded body 28 is sent into the air passage 32. The air passages 32, that is, the gaps between the columnar protrusions 16 are formed on one side as shown in FIG. 14 is formed continuously from the inner peripheral part to the outer peripheral edge, and is open at the outer peripheral edge of the plate-like part 12, so that the gas flowing into the air passage 32 is as shown by arrows in FIGS. , All are quickly discharged to the outside of the setter 10 for firing. That is, degreasing is performed quickly despite the fact that the other surface 20 of the plate-like portion 12 with which the sheet-like molded body 28 is in contact is configured to be flat.

  In addition, since the cracked gas and the like are discharged at the same time, the atmospheric gas in the firing furnace enters the ventilation path 32, so that the temperature difference between the inner peripheral portion and the outer peripheral portion of the firing setter 10 is relaxed, Good temperature distribution is obtained. As is clear from the above description, in the present embodiment, the air passage 32 having an open upper surface is formed on the one surface 14.

  The result of firing the sheet-like molded body 28 using the firing setter 10 in this manner will be described. The fired product is, for example, a green sheet called a low-temperature fired substrate prepared by mixing glass and ceramic powder and having, for example, three layers each having a size of about 60 × 80 × 0.2 (mm). Is. Cu wiring is formed inside and on the surface of this laminated sheet, but is omitted in FIG. This is degreased at a temperature of about 200 (° C.) in air and then fired at a temperature of about 940 (° C.) in a non-oxidizing atmosphere, whereby a Cu wiring low-temperature fired substrate is obtained. In firing, when the above-mentioned sheet-like molded body 28 was fired using the firing setter 10, a flat substrate with a white color tone could be obtained.

  On the other hand, when the second setter 30 was stacked and fired with the sheet-like molded body 28 being sandwiched, the color tone of the fired product was gray and degreasing was insufficient. The gray color is due to a very small amount of carbon adhering to the substrate surface, but this carbon lowers the insulation resistance of the substrate surface and is harmful to subsequent processes such as mounting of components on the surface. Further, without using the setters 10 and 30, when fired with a mean particle size of about 0.1 (mm) between the sheet-like molded bodies 28, for example, a white fired product was obtained. A large amount of fine sand adhered to the surface, and it was necessary to remove the fine sand by liquid honing. Moreover, the surface unevenness was large and the flatness was insufficient.

Further, a green sheet having a thickness dimension of (La, Ca) MnO ₃ of about 0.8 (mm) was prepared as the sheet-like molded body 28, and similarly evaluated by performing a baking treatment at a temperature of about 1320 (° C.). . A good fired product was obtained when the setter 34 for firing was used, but the surface roughness was poor when using the mesh sand, and in the case where the sheet-shaped molded body 28 was sandwiched between the second setters 30, the binder A large number of small holes that were considered to be poor burnout were observed. The color tone after firing was dark gray and there was no difference.

  In short, according to the present embodiment, the air passage 32 communicating with the outer peripheral edge is formed by projecting the columnar protrusion 16 on the one surface 14 of the porous plate-like portion 12 having the fine continuous air holes 22. Therefore, the firing setter 10 is formed with a gas passage through the plate-like portion 12 from the other surface 20 to the one surface 14 side in the thickness direction and through the air passage 32 to the outer peripheral edge. . Therefore, although the other surface 20 on which the sheet-like molded body 28 is placed is flat, the degreasing gas is suitably discharged and the uniformity of the temperature distribution is improved. That is, it becomes possible to achieve both degreasing and flatness.

  Next, another embodiment of the present invention will be described. In the following description, parts common to the above-described embodiments are denoted by the same reference numerals and description thereof is omitted.

  FIG. 5 shows a stack of sheet-like molded bodies 28 using a setter 34 for firing instead of the setter 10 for firing. The setter 34 for firing corresponds to an integrated setter 10 for firing and the second setter 30. That is, a pair of plate-like parts 36 and 36 are connected to each other by a large number of columnar connecting parts 38. The plate-like portions 36 and 36 are configured in the same manner as the plate-like portion 12. Further, the columnar connecting portion 38 is configured in the same manner as the columnar protrusion 16 described above. Therefore, an air passage 42 similar to that formed at the time of firing in the above embodiment is formed between the inner surfaces 40, 40 of the plate-like portions 36, 36 facing each other. In this embodiment, the columnar connecting portion 38 corresponds to a support portion.

  Even when the setter 34 for firing thus configured is used, since the plate-like portions 36 and 36 are integrated in the same manner as the setter 10 for firing, the setter 10 for firing is used. The same effect as when used is obtained. In addition, the thickness dimension of the plate-like parts 36 and 36 is about 0.2 (mm), for example, the height dimension of the columnar connecting part 38 is about 0.1 (mm), and the thickness dimension of the entire setter 34 is 0.5 (mm), for example. ) Degree. That is, it is thinner by about 0.1 (mm), that is, 16 (%) than when the setters 10 and 30 are used in an overlapping manner, and the kiln packing efficiency is further enhanced. In addition, since it is only necessary to alternately stack the setter 34 and the fired product, there is an advantage that the labor of stacking is reduced.

  FIG. 6 is a process diagram for explaining a method of manufacturing the setter 34. Processes R1 to R3 and R5 are substantially the same as the processes P1 to P4 shown in FIG. 3, and only differences will be described. In the sheet forming step R1, only the green sheet A is formed, and in the firing step R2, only the green sheet A is fired to obtain the porous alumina plate A for constituting the plate-like portion 36. In the stacking step R4 subsequent to the protrusion forming step R3, another porous alumina plate A is stacked on the columnar protrusions formed on the porous alumina plate A, and the firing process is performed in the firing step R5 in that state. Apply. Thereby, the columnar protrusion and the pair of porous alumina plates A are joined to each other by the liquid phase generated in the process of densifying the columnar protrusion, and the setter 34 is obtained. In the lamination process, for example, a solvent such as terpineol is applied to the front end surface of the columnar protrusion and the inner surface of the plate-like portion 12 to be laminated, and is temporarily joined by pressurizing at a low pressure in a stacked state.

  When the columnar protrusions are made of the same material as the plate-like portion 36, that is, a slurry and printing ink prepared so as to be porous materials having the same porosity, the firing shrinkage rates of both are substantially the same. Therefore, the firing step R2 is unnecessary. That is, the columnar protrusions can be printed on the green sheet A that has not been fired, and the other green sheets A can be laminated and fired at once. The same applies to the firing setter 10 described above. As described above, when only columnar protrusions are densely formed, the shrinkage rate of firing of the columnar protrusions is relatively large. Therefore, when fired at the same time, contraction stress acts on the green sheet A, and flatness is obtained. Disappear. Therefore, the steps shown in FIGS. 3 and 6 are separately fired.

  FIG. 7 is a view showing a firing setter 44 of still another embodiment. On one surface 48 of the plate-like portion 46 of the setter 44 for firing, a plurality of protrusions 50 extending along one side of the plate-like portion 46 are arranged in parallel to each other at a constant central interval instead of the columnar protrusions 16. Is provided.

  The plate-like portion 46 has a thickness dimension of about 0.2 (mm), for example, and has the same porosity and average pore diameter as the plate-like portion 12, for example. Further, the protrusion 50 formed thereon has a height dimension of about 0.3 (mm) and a width dimension of about 0.3 (mm), and is provided at a center interval of about 0.3 (mm). Is located on the outer peripheral edge of the plate-like portion 46. Therefore, the overall thickness dimension of the setter 44 is about 0.7 (mm).

  The setter 44 is manufactured, for example, by preparing a clay for extrusion molding in which the amount of the binder and the amount of the solvent are smaller than those obtained by molding the green sheet, and firing the molded body that has been extrusion molded. At this time, the die of the extrusion molding machine having the shape of the left end face in FIG. 7 of the setter 44 where the tip of the protrusion 50 is located is used. That is, as shown in FIG. 8, a base 58 including a long hole portion 54 extending in the lateral direction and a plurality of branch hole portions 56 having the same length extending from a plurality of locations on one side perpendicularly to the one side. It is molded using.

  The setter 44 configured in this manner is used in a state where a linear air passage 52 is formed between the protrusions 50 by being overlapped with the flat second setter 30 similarly to the setter 10. Therefore, the gas that has entered the air passage 52 through the porous plate-like portion 46 is discharged from both ends of the protrusion 50 through the air passage 52. Therefore, according to the present embodiment, the opening surface of the air passage 52 is limited as compared with the setter 10, but the opening area of each air passage 52 is increased as is apparent from the above-described numerical values. Sufficient degreasing property is obtained.

  Note that the setter 44 may be one in which a plate-like portion 60 configured in the same manner as the plate-like portion 46 is integrally formed as shown by a one-dot chain line in FIG. As shown in FIG. 9, such a setter can be formed by extrusion using a base 64 provided with a long hole 62 on the distal end side of the branch hole 56. In this base 64, the portions between the branch holes 56 are connected on the back side by a back plate provided with a number of fine through holes, as is generally done with a base for extrusion molding.

  As mentioned above, although this invention was demonstrated in detail with reference to drawings, this invention can be implemented also in another aspect, A various change can be added in the range which does not deviate from the main point.

It is a perspective view which shows the setter for baking which is an example of the plate-shaped structure of this invention. It is a figure which expands and shows the principal part cross section of the setter for baking of FIG. It is process drawing explaining the manufacturing method of the setter for baking of FIG. It is sectional drawing explaining the use condition of the setter for baking of FIG. It is sectional drawing corresponding to FIG. 4 explaining the use condition of the setter for baking of the other Example of this invention. It is process drawing explaining the manufacturing method of the setter for baking of FIG. It is a perspective view which shows the setter for baking of the further another Example of this invention. It is a front view of an example of the nozzle | cap | die for extrusion-molding the setter for baking of FIG. It is a front view of the other example of a nozzle | cap | die for extruding the setter for baking of FIG.

Explanation of symbols

10: setter for firing, 12: plate-like portion, 14: one side, 16: columnar protrusion, 20: other side, 22: continuous vent

Claims (8)

A porous plate-like portion having a large number of fine communication holes communicating from one surface to a flat other surface;
A plurality of air passages having a predetermined shape communicating from the outer peripheral edge to the inner peripheral portion are formed on the entire surface by projecting on the one surface so that the front end surface is located on one plane parallel to the other surface. A plate-like structure provided with an air passage characterized by including a support part.   2. The plate according to claim 1, further comprising a second plate-like portion having a first surface parallel and flat to the other surface and connected to the tips of the plurality of support columns on a second surface on the back surface side. Structure. ^2. The plate-like structure according to claim 1, wherein a minimum value of a ventilation cross-sectional area between a plane passing through the front end surfaces of the plurality of support portions and one surface of the plate-like portion is 0.004 (mm ² ) or more.   The plate-like structure according to claim 1, which is used as a setter for firing for firing a thin plate-like ceramic molded body. A sheet forming step of producing a green sheet using a predetermined ceramic raw material;
A protrusion forming step of forming a plurality of protrusions on one surface of the green sheet using the predetermined ceramic raw material to form a recess having a predetermined shape communicating with the inner periphery from the outer peripheral edge;
By firing the green sheet on which the plurality of protrusions are formed, a porous plate-like portion having a large number of fine communication holes communicating from the one surface to the other surface is generated from the green sheet and at the same time And a firing step of generating a plurality of support portions from the plurality of protrusions.   6. The method for manufacturing a plate-like structure according to claim 5, further comprising a lamination step of laminating another green sheet produced in the same manner as the green sheet on the plurality of projections after the projection forming step. A plurality of holes formed such that the tip is located on a straight line parallel to the other long side from a plurality of long holes on one long side and the other long side of the long hole. By extruding a clay of a predetermined ceramic raw material from a base provided with a branch hole portion on the tip surface, a plurality of protrusions parallel to each other are provided on one surface of the plate-like portion and a flat other surface is provided. A molding step for obtaining a plate-like molded body;
A firing step of firing the plate-like formed body to produce a porous plate-like portion and a plurality of protrusions projecting on one surface of the porous plate-like portion. Production method. The forming step is to extrude the clay of the predetermined ceramic raw material with a die having a second long hole portion that is parallel to the long hole portion and connected to the tips of the plurality of branch hole portions. A method for producing a plate-like structure according to claim 7.

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