JP5331034B2 - Green sheet manufacturing apparatus and manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device and a method for manufacturing a green sheet capable of preventing a carrier film from warping and capable of uniforming the thickness of a liquid slurry when regulating the thickness of the liquid slurry with a doctor blade. <P>SOLUTION: The device 101 for manufacturing the green sheet includes a liquid reservoir 2 for accumulating the liquid slurry 4a, a belt-like carrier film 6 which travels in one direction and wherein the liquid slurry is continuously coated on the own upper surface from the liquid reservoir, the doctor blade 7 which is disposed with a definite gap G from the upper surface of the carrier film, and regulates the thickness of the liquid slurry continuously coated on the carrier film depending on the gap G, a drying furnace 8 for drying the liquid slurry having the thickness regulated with the doctor blade, and warpage pressing members 10 which are disposed at the position of both ends 6e of the carrier film having no liquid slurry coated thereon and overlapped with at least a doctor blade in the traveling direction L, and prevents the both ends from warping upward by contacting to the upper surface of the both ends. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a manufacturing apparatus and a manufacturing method of a green sheet used for a heater element, a sensor element, a ceramic capacitor, a substrate for a ceramic package, and the like.

  Conventionally, a method for producing a ceramic sheet using a doctor blade is known (see, for example, Patent Documents 1 and 2). This method is performed as follows. First, the slurry liquid (slurry) formed by mixing and dispersing the raw material powder, the solvent and the binder material is continuously applied on the traveling carrier film. Then, the thickness of the slurry is adjusted by scraping off the slurry with a doctor blade arranged with a certain gap from the upper surface of the carrier film. The slurry whose thickness is adjusted is conveyed on a carrier film and introduced into a drying furnace, and the slurry is heated and dried to produce a green sheet.

JP-A-7-187803 JP 2009-208395 A

However, when the carrier film is repeatedly used, there is a problem that both ends of the carrier film warp toward the side (upper side) on which the slurry is applied. This is because the solvent in the slurry is volatilized and removed in the drying furnace, and the slurry shrinks when changing to a green sheet, and the carrier film is pulled to the upper side of the film on which the slurry is applied. It is. In particular, the both ends of the film are more likely to warp than the center. When the slurry is applied again on the warped carrier film, the gap between the warped portion of the film and the doctor blade becomes narrower than before the film warps. For this reason, the thickness of the slurry becomes non-uniform before and after warping, and the thickness of the slurry becomes non-uniform even between the center of the film and both ends of the film after the warping occurs.
On the other hand, if the carrier film is replaced every time warping occurs, the productivity of the green sheet is significantly reduced.

In the technique described in Patent Document 1, the green sheet is rolled in a drying furnace to make the film thickness uniform after drying. However, if both ends of the carrier film are warped when the slurry passes through the doctor blade, the thickness of the slurry becomes thin at both ends of the carrier film, so it is difficult to recover the thickness at both ends even when rolling in a drying furnace. There is a case. Further, since the slurry before drying in the drying furnace is viscous and adheres to the rolling roll, it is difficult to roll the slurry before drying to make the thickness uniform.
Therefore, the present invention provides a green sheet manufacturing apparatus and manufacturing method capable of preventing the carrier film from warping and adjusting the thickness of the slurry when adjusting the thickness of the slurry with a doctor blade. The purpose is to do.

In order to solve the above-described problems, the green sheet manufacturing apparatus of the present invention includes a liquid reservoir for storing slurry liquid obtained by mixing and dispersing raw material powder, a solvent and a binder material, and traveling in one direction, and the upper surface of itself. A belt-like carrier film on which the slurry solution is continuously applied from the liquid reservoir, and a fixed gap from the upper surface of the carrier film, and a continuous gap is formed on the carrier film based on the gap. A doctor blade that adjusts the thickness of the mud serum applied to the surface, and the mud fluid adjusted in thickness by the doctor blade is heated and dried, and is disposed downstream of the doctor blade in the traveling direction of the carrier film. And a drying furnace, wherein the carrier film is not coated with the slurry solution at both ends, and In serial running direction is arranged at least in the overlap with the doctor blade position, the contact with the upper surface of the carrier film provided with a warp pressing member to prevent the said end portion is warped upward, further wherein the warp holding member, the traveling A plurality of or all of the intermediate region between the doctor blade and the inlet of the drying furnace is in contact with the upper surfaces of the both end portions along the direction .
In this case, the warp holding member prevents the both end portions of the carrier film from warping at the position where the thickness of the slurry fluid is adjusted by the doctor blade, so that the gap between the carrier film and the doctor blade is increased. The central portion and both end portions can be kept constant, and the thickness of the slurry can be made uniform. Even if the carrier film is already warped, it can be applied so that the thickness of the slurry is uniform between the center and both ends of the carrier film. Longer and more productive.
Further, it is possible to prevent the thickness of the slurry from changing due to warping of both ends in the intermediate region. In particular, the slurry fluid before being heated and dried in a drying furnace has low shape retention, and if the carrier film is warped after adjusting the thickness with a doctor blade, the slurry fluid coated at positions close to both ends of the carrier film is carrier. Although there is a possibility that the film flows to the center of the film and the thickness becomes non-uniform, according to this manufacturing apparatus, it is possible to prevent the mud from flowing before drying.

The warp holding member is an intermediate region between the doctor blade and the inlet of the drying furnace, and is in surface contact or point contact with the upper surface of the both ends in the width direction perpendicular to the traveling direction of the carrier film. It may be.
If it does in this way, if it is a surface contact, both ends can be certainly pressed down with a curvature pressing member, and prevention of curvature can be performed more certainly. If it is point contact, the frictional force between the warp pressing member and the carrier film can be reduced, and the carrier film can be smoothly run.

It is preferable that a lubricant is present in a portion of the warp pressing member that contacts the both end portions.
If it does in this way, the frictional force between a curvature pressing member and a carrier film can be reduced, and a carrier film can run smoothly.

The warp pressing member may be in contact with the upper surfaces of the both end portions in the drying furnace.
If it does in this way, the curvature of a carrier film can be prevented in the inside of the drying furnace which is in the state in which the solvent in mud liquid is easy to volatilize because of high temperature.
Also, since the mud liquid hardly shrinks after drying, if the warp holding member is provided until the mud liquid dries and keeps its shape, the carrier film may warp after passing through the warp holding member, Almost eliminated. Therefore, it becomes possible to increase the use frequency of a carrier film more by using this manufacturing apparatus.
The warp holding member may be disposed entirely or partially within the drying furnace, but the warp holding member is disposed inside the drying furnace where drying of the slurry liquid is likely to occur, and the drying furnace. Preferably in the vicinity of the inlet. More preferably, the warp pressing member may be disposed over the entire interior of the drying furnace.

The green sheet manufacturing method of the present invention includes a doctor blade having a certain gap provided on the upper surface of a traveling carrier film, and continuously mixes and disperses the slurry powder, solvent and binder material from the gap. A coating adjusting step of adjusting the thickness of the applied slurry solution while coating on the carrier film, and the slurry solution adjusted in thickness by the doctor blade is heated and dried in a drying furnace to obtain a green sheet. A heating and drying step of forming a carrier film, and when the carrier film passes through a doctor blade, the upper surface of both ends of the carrier film to which the slurry is not applied, and the traveling direction of the carrier film together with the pressing of the doctor blade and the overlapping position, the both end portions can be prevented from warping upward in the carrier film Serial even at a plurality of positions or all of the intermediate region between from passing through the doctor blade is introduced into the inlet of the drying furnace, holding the upper surface of said end portions, said end portions can be prevented from warping upward.
This prevents both ends of the carrier film from warping at the position of the doctor blade that adjusts the thickness of the slurry, so that the gap between the carrier film and the doctor blade is set at the center and both ends of the carrier film. The thickness of the slurry can be made uniform. Even if the carrier film has already warped, the slurry can be applied so that the thickness of the slurry is uniform at the center and both ends of the carrier film. The use of film is possible.
Also, it is possible to prevent the mud from changing in thickness due to warping of both ends in an intermediate region between the doctor blade and the inlet of the drying furnace. In particular, the slurry fluid before being heated and dried in a drying furnace has low shape retention, and if the carrier film is warped after adjusting the thickness with a doctor blade, the slurry fluid coated at positions close to both ends of the carrier film is carrier. Although there is a possibility that the film flows to the center of the film and the thickness becomes non-uniform, in the present production method, it is possible to prevent the slurry from flowing before drying.

In the green sheet manufacturing method of the present invention, it is preferable that the upper surfaces of the both end portions introduced into the drying furnace are pressed to prevent the both end portions from warping upward.
If it does in this way, the curvature of a carrier film can be prevented in the inside of the drying furnace which is in the state in which the solvent in mud liquid is easy to volatilize because of high temperature.
In addition, since the mud liquid hardly shrinks after drying, the carrier film can be warped upward by preventing both ends from warping upward until the mud liquid dries and maintains its shape. Disappear. Therefore, it becomes possible to increase the use frequency of a carrier film more by using this manufacturing apparatus.
It should be noted that when preventing warping in the drying furnace, warping may be prevented while passing through the drying furnace, and some warping in the drying furnace may be prevented. It is preferable to prevent upward warping in the drying furnace where the liquid tends to dry and in the vicinity of the inlet of the drying furnace. More preferably, it is good to prevent upward warping throughout the interior of the drying furnace.

  According to the present invention, it is possible to prevent the both ends of the carrier film from warping upward when the thickness of the slurry is adjusted with the doctor blade or until the slurry applied on the carrier film is dried. . And the thickness of the slurry liquid coated on a carrier film can be made uniform.

It is a perspective view which shows schematic structure of the manufacturing apparatus of the green sheet which concerns on the 1st Embodiment of this invention. It is a side view of the manufacturing apparatus of the green sheet which concerns on the 1st Embodiment of this invention. It is sectional drawing which follows the AA line of FIG. It is a perspective view which shows schematic structure of the manufacturing apparatus of the green sheet which concerns on the 2nd Embodiment of this invention. It is a side view of the manufacturing apparatus of the green sheet which concerns on the 2nd Embodiment of this invention. It is sectional drawing which follows the BB line of FIG. It is a perspective view which shows schematic structure of the manufacturing apparatus of the green sheet which concerns on the 3rd Embodiment of this invention. It is sectional drawing which follows the CC line of FIG.

Hereinafter, embodiments of the present invention will be described.
FIG. 1 is a perspective view showing a schematic configuration of a green sheet manufacturing apparatus 101 according to the first embodiment of the present invention, and FIG. 2 is a side view of the green sheet manufacturing apparatus 101 according to the first embodiment of the present invention. 3 is a cross-sectional view taken along the line AA of FIG.
In FIG. 1, a green sheet manufacturing apparatus 101 has a loop shape and a plurality of rollers 70 that support and run a belt-like carrier film 6 while applying tension, and a slurry liquid placed on the carrier film 6. (Slurry) A substantially box-shaped liquid reservoir 2 for storing 4a, a doctor blade 7 attached to the right side plate of the liquid reservoir 2, a drying furnace 8, and a pair of warp pressing members 10 are provided.
The bottom of the right side plate (the side plate on the downstream side in the running direction L of the carrier film 6) 2p of the liquid reservoir 2 is provided with an elongated opening 2s having a length W in the longitudinal direction, and the carrier located below the liquid reservoir 2. The slurry 4a is continuously applied to the upper surface of the film 6 with a width W. On the other hand, the width of the carrier film 6 is wider than W, and the slurry 4a is not applied to both end portions 6e of the carrier film 6 so that the film is exposed. The slurry 4a is obtained by mixing and dispersing raw material powder, a solvent, and a binder material. The raw material powder is, for example, alumina powder.

  The doctor blade 7 is attached to the upper end of the opening 2 s of the liquid reservoir 2, and the upper surface of the carrier film 6 and the lower end surface of the doctor blade 7 form a certain gap G. At the point where the gap G becomes the smallest (the point where the distance between the carrier film 6 and the doctor blade 7 becomes the smallest), the doctor blade 7 adjusts the thickness of the slurry 4a while scraping off the excess slurry 4a on the carrier film. . The slurry 4a whose thickness is adjusted by the doctor blade 7 is introduced into the drying furnace 8 together with the carrier film 6, and after the slurry 4a is heated and dried, it becomes a green sheet 4 and is taken out from the drying furnace 8.

Each warp pressing member 10 is formed in a plate shape elongated in the running direction L, and the plate surface is in contact with both ends 6e, which are both ends of the carrier film 6, so as to prevent upward warping of both ends 6e. It has become. One end of the long side of the warp pressing member 10 is attached on a support plate 12 extending in the running direction L, and the warp pressing member 10 and the support plate 12 have an L-shaped cross section. The support plate 12 is supported by a plurality of support columns 14 erected in the vertical direction, and finely adjusts the mounting position of the support plate 12 and the support columns 14 so that the distance between the warp pressing member 10 and the carrier film 6 can be adjusted. ing.
Specifically, in the traveling direction L, the warp pressing member 10 is disposed at least at a position overlapping with the doctor blade, and is in contact with the upper surfaces of both end portions 6e at this portion.
Here, in the present embodiment, the lower surface of the doctor blade 7 has a width (thickness) in the traveling direction L (the lower surface of the doctor blade 7 forms a triangular bottom surface), and the lower surface is parallel to the upper surface of the carrier film 6. It has become. In this case, the “overlapping position” refers to all the portions where the gap between the doctor blade 7 and the upper surface of the carrier film 6 is the smallest and parallel to the upper surface of the carrier film 6. Further, each warp pressing member 10 is intermediate between the doctor blade 7 in the traveling direction L of the carrier film 6 and the inlet 8i of the drying furnace 8 (the portion of the outer edge of the drying furnace 8 on the most upstream side in the traveling direction L). It extends to the region M (see FIG. 2), and further extends beyond the intermediate region M to the inside of the drying furnace 8 and the right side plate 2p of the liquid reservoir 2.

As shown in FIG. 2, a flat base 80 on which the carrier film 6 is placed is disposed between the liquid reservoir 2 and the drying furnace 8 along the running direction L. The plane shape is maintained.
Further, the mounting position of the warp pressing member 10 is adjusted so that the lower surface 10 a of the warp pressing member 10 is substantially flush with the upper surfaces of both end portions 6 e, and the carrier film 6 has an upper surface of the base 80 and the warp pressing member 10. While traveling through the gap with the lower surface 10a, the lower surface 10a of the warp pressing member 10 is pressed by the lower surface 10a to prevent both end portions 6e from warping upward.

As shown in FIG. 3, a pair of support plates 12 and struts 14 are arranged so as to sandwich the carrier film 6, and each warp pressing member 10 extends from each support plate 12 toward the carrier film 6. The lower surface 10a is in surface contact with the upper surfaces of both ends 6e.
Here, since silicone as a lubricant is applied to the lower surface 10a of the warp holding member 10 and the frictional force with the carrier film 6 is reduced, the carrier film runs smoothly.

As described above, in the traveling direction L, the warp pressing member 10 is in contact with the upper surfaces of both end portions 6e at least at a position overlapping with the doctor blade 7. For this reason, since both ends 6e are prevented from warping just at the position where the thickness of the slurry 4a is adjusted by the doctor blade 7, the gap between the carrier film 6 and the doctor blade 7 is kept constant, and the thickness of the slurry Can be made uniform. Also, even if the carrier film has already warped, the slurry can be applied so that the thickness of the slurry is uniform at the center and both ends of the carrier film, so the carrier film replacement period becomes longer. , Improve productivity.
Further, not only at the same position as the doctor blade 7, but also when the warp pressing member 10 is in contact with the upper surfaces of both ends 6e in at least a part of the intermediate region M, both end portions 6e warp again in the intermediate region M and the slurry 4a. It is preferable because the thickness can be prevented from changing. In particular, the slurry 4a before being heated and dried in the drying furnace 8 has low shape retention, and when the carrier film 6 warps again after adjusting the thickness by the doctor blade 7, the slurry 4a flows to the center of the carrier film 6 and becomes thick. May become non-uniform.
Furthermore, it is more preferable that the warp pressing member 10 is in contact with the upper surfaces of both ends 6e even inside the drying furnace 8, because the carrier film 6 can be prevented from warping until the slurry 4a is dried and maintains its shape.

  In the case of the first embodiment, the warp pressing member 10 is in surface contact with both end portions 6e in the entire intermediate region M along the traveling direction L, and both ends 6e in a plane perpendicular to the traveling direction L. Surface contact. For this reason, it can prevent that the curvature pressing member 10 presses the both ends 6e reliably, and a carrier film warps upward.

Next, the configuration of the green sheet manufacturing apparatus 102 according to the second embodiment of the present invention will be described with reference to FIGS. The green sheet manufacturing apparatus 102 is the same as that of the first embodiment except that the configuration of the warp pressing member 20 is different. Therefore, the same components as those of the first embodiment are denoted by the same reference numerals and detailed. The detailed explanation is omitted.
4 is a perspective view showing a schematic configuration of the green sheet manufacturing apparatus 102, FIG. 5 is a side view of the green sheet manufacturing apparatus 102, and FIG. 6 is a cross-sectional view taken along line BB in FIG.

In FIG. 4, the warp pressing member 20 is a plurality (three in this example) pivotally supported on each inner side surface (side surface facing the carrier film 6) of a pair of elongated support plates 22 extending in the running direction L. The wheels 20 are arranged in a line at equal intervals along the traveling direction L. Further, the vicinity of the center of the support plate 22 is supported by one support column 24 erected in the vertical direction, and the attachment position between the support plate 22 and the support column 24 is finely adjusted, so that the warp pressing member 20 and the carrier film 6 are adjusted. The interval can be adjusted.
And each wheel 20 pivotally supported by the inner surface of each support plate 22 touches on both ends 6e, and both wheels come into point contact while each wheel 20 rotates as the carrier film 6 travels. Yes.

As shown in FIG. 5, the contact point 20 a between the most upstream wheel 20 in the traveling direction L (the left wheel 20 in FIG. 5) and the both end portions 6 e is in a position overlapping the doctor blade 7 in the traveling direction L. Further, the contact points 20a between the other two wheels 20 and both end portions 6e are in two places in the intermediate region M.
In addition, the support plate 22 and the support | pillar 24 are not displayed in FIG. 5 so that the contact 20a may become clear.

As shown in FIG. 6, a pair of support plates 22 and support columns 24 are arranged so as to sandwich the carrier film 6, and the wheels 20 that are pivotally supported on the inner surface of each support plate 22 protrude toward the carrier film 6. 20 is in point contact with the upper surfaces of both end portions 6e.
Here, the surface of the wheel (warp pressing member) 20 that comes into contact with the carrier film is made of Teflon (registered trademark) having lubricity, and reduces the frictional force between the carrier film 6 and the traveling carrier film 6.
Further, the mounting position of the wheel 20 is adjusted so that the wheel 20 is in point contact with the upper surfaces of both ends 6e, and the carrier film 6 is pressed by the wheel 20 while traveling through the gap between the upper surface of the base 80 and the wheel 20. The upper end of the both ends 6e is prevented.

Thus, also in the case of the second embodiment, in the traveling direction L, the warp pressing member 20 is in contact with the upper surfaces of the both end portions 6e at least at a position overlapping the doctor blade 7. For this reason, the gap between the carrier film 6 and the doctor blade 7 can be kept constant, and the thickness of the slurry can be made uniform.
In the case of the second embodiment, the wheel (warp holding member) 20 is in point contact with both end portions 6e along the traveling direction L at three positions of the intermediate region M and the doctor blade 7, and the traveling direction L Even in a plane perpendicular to the both ends 6e, point contact is made. For this reason, compared with a surface contact, the frictional force of the curvature pressing member 20 and the both ends 6e is low, and the carrier film 6 can be smoothly run.

Next, the configuration of the green sheet manufacturing apparatus 103 according to the third embodiment of the present invention will be described with reference to FIGS. The green sheet manufacturing apparatus 103 is the same as that of the first embodiment except that the configuration of the warp pressing member 30 is different. Therefore, the same components as those of the first embodiment are denoted by the same reference numerals and detailed. The detailed explanation is omitted.
7 is a perspective view showing a schematic configuration of the green sheet manufacturing apparatus 103, and FIG. 8 is a sectional view taken along the line CC of FIG.

In FIG. 7, the pair of warp pressing members 30 have a plate shape elongated in the traveling direction L, and one end of the long side of the warp pressing member 30 is attached on a support plate 32 extending in the traveling direction L. Further, when viewed from the direction perpendicular to the running direction L, the warp pressing member 30 is disposed so that the plate surface of the warp pressing member 30 is inclined downward from the outside to the inside of the carrier film 6. And the other end of the long side of the warp pressing member 30 falling toward the carrier film 6 is in contact with the both ends 6e at points to prevent upward warping of both ends 6e.
Further, the support plate 32 is supported by a plurality of support columns 34 erected in the vertical direction, and the attachment position between the support plate 32 and the support columns 34 can be finely adjusted, and the distance between the warp pressing member 30 and the carrier film 6 can be adjusted. It has become.
In the running direction L, the warp pressing member 30 is disposed at the same position as the warp pressing member 10.

As shown in FIG. 8, a pair of support plates 32 and columns 34 are arranged so as to sandwich the carrier film 6, and each warp pressing member 30 extends from each support plate 32 toward the carrier film 6, and the warp pressing member 30 plate surfaces are slantingly descending from the outside to the inside of the carrier film 6. Then, the long side end 30a of the warp pressing member 30 is in point contact with the upper surfaces of both end portions 6e.
The mounting position of the warp pressing member 30 is adjusted so that the end 30a of the warp pressing member 30 is at the same height as the upper surfaces of both end portions 6e. While traveling through the gap with the end 30a, it is pressed by the end 30a to prevent both end portions 6e from warping.

Thus, also in the case of the third embodiment, in the traveling direction L, the warp pressing member 30 is in contact with the upper surfaces of the both end portions 6e at a position at least overlapping with the doctor blade 7. For this reason, the gap between the carrier film 6 and the doctor blade 7 can be kept constant, and the thickness of the slurry can be made uniform.
In the case of the third embodiment, the warp pressing member 30 is in surface contact with both end portions 6e along the traveling direction L, and is in point contact with both end portions 6e in a plane perpendicular to the traveling direction L. . For this reason, the warp pressing member 30 reliably presses the both end portions 6e by surface contact along the traveling direction L, and the frictional force with the both ends 6e is low on a plane perpendicular to the traveling direction L, so that the carrier film 6 travels. Can be performed smoothly.

It goes without saying that the present invention is not limited to the above-described embodiment, but extends to various modifications and equivalents included in the spirit and scope of the present invention.
For example, a lubricant may be laminated on a portion of the warp pressing member 10 that contacts the both ends of the carrier film 6. The carrier film 6 itself may be used as this lubricant.

Further, in the present invention, it is defined that at least the warp pressing member 10 is disposed at a position overlapping with the doctor blade 7 in the traveling direction of the carrier film 6, but this “overlapping position” means that the doctor blade 7 is in the traveling direction L. In the case where the mud fluid on 6 is substantially in contact with only one point (for example, a doctor blade has a knife shape or the like), this contact point is obtained.
On the other hand, as shown in FIGS. 1 and 2, the lower surface of the doctor blade 7 has a width (thickness) in the traveling direction L (in FIGS. 1 and 2, the lower surface of the doctor blade 7 forms a triangular bottom surface). When the lower surface is parallel to the upper surface of the carrier film 6, the thickness of the slurry is first adjusted on the most upstream side of the doctor blade 7. Therefore, the uppermost stream side of the doctor blade 7 is an “overlapping position”, and at least the uppermost stream side of the doctor blade 7 needs to be provided with a warp pressing member. However, even if the warp of the film is suppressed only on the uppermost stream side of the doctor blade 7 (on the side opposite to the drying furnace along the running direction L), and then the lower surface of the doctor blade 7 travels while returning the warp of the film, There may be a problem that the thickness of the slurry is adjusted while the film is warped. Therefore, in this case, it is more preferable that the warp pressing member is disposed in all the portions where the gap between the doctor blade 7 and the upper surface of the carrier film 6 is the smallest and parallel to the upper surface of the carrier film 6. .
Even if the lower surface of the doctor blade 7 has a width (thickness) in the traveling direction L, the gap between the doctor blade 7 and the upper surface of the carrier film 6 is the smallest when the lower surface is not parallel to the upper surface of the carrier film 6. The thickness of the slurry is adjusted only in the part. When there is only one point of contact between the doctor blade 7 and the slurry fluid on the carrier film 6 in the traveling direction L, this point of contact corresponds to the “overlapping position”. When there are a plurality of contacts between the doctor blade 7 and the slurry fluid on the carrier film 6 in the traveling direction L, the most upstream contact among these contacts corresponds to the “overlapping position”. The warp pressing member needs to be disposed, but more preferably, the warp pressing member is disposed at all the contacts.

  Furthermore, the present invention is particularly suitable for a method for producing a green sheet for a gas sensor element or a heater element. This is because when a green sheet for a gas sensor element or a heater element is made, the slurry shrinks greatly during drying because it contains more volatile solvent than when a green sheet used for a ceramic package substrate or the like is made. This is because the carrier film is more likely to warp.

2 Liquid reservoir 4 Green sheet 4a Mud liquid 6 Carrier film 6e Both ends 7 Doctor blade 7a Tip of doctor blade 8 Drying furnace 8i Drying furnace inlet 10, 20, 30 Warp holding member 101-103 Green sheet manufacturing apparatus G Carrier film And doctor blade gap L Carrier film travel direction M Middle area

Claims (6)

A liquid reservoir for storing slurry liquid obtained by mixing and dispersing raw material powder, solvent and binder material;
A belt-like carrier film that travels in one direction and is continuously coated with the slurry from the reservoir on its upper surface;
A doctor blade that is arranged with a certain gap from the upper surface of the carrier film, and based on the gap, adjusts the thickness of the slurry liquid continuously applied on the carrier film;
Heat drying the slurry whose thickness is adjusted by the doctor blade, a drying furnace disposed downstream of the doctor blade in the traveling direction of the carrier film,
In an apparatus for producing a green sheet having
The both ends of the carrier film to which the slurry is not applied are disposed at positions overlapping at least the doctor blade in the running direction, and the both ends warp upward in contact with the upper surface of the carrier film. comprising a warp pressing member to prevent,
Further, the warp pressing member is a green sheet manufacturing apparatus that is in contact with the upper surfaces of the both ends at a plurality of or all of the intermediate region between the doctor blade and the inlet of the drying furnace along the traveling direction . The warp pressing member is an intermediate region between the doctor blade and the inlet of the drying furnace, and is in surface contact or a point on the upper surface of the both ends in the width direction perpendicular to the traveling direction of the carrier film, respectively. The green sheet manufacturing apparatus according to claim 1, which is in contact with the green sheet. The green sheet manufacturing apparatus according to claim 1 , wherein a lubricant is present in a portion of the warp pressing member that contacts the both end portions . The apparatus for producing a green sheet according to any one of claims 1 to 3, wherein the warp pressing member is in contact with the upper surfaces of the both end portions even inside the drying furnace .   A doctor blade is provided with a certain gap from the upper surface of the carrier film traveling in one direction, and the slurry liquid obtained by mixing and dispersing the raw material powder, the solvent and the binder material from the gap is continuously provided on the upper surface of the carrier film. A coating adjustment step of adjusting the thickness of the applied slurry fluid while coating
  A heating and drying step of forming a green sheet by heating and drying the slurry whose thickness is adjusted by the doctor blade in a drying furnace;
  In the manufacturing method of the green sheet having
  When the carrier film passes through the doctor blade, the upper surface of both ends of the carrier film to which the slurry is not applied, and a position overlapping with the doctor blade in the traveling direction of the carrier film, While preventing both ends warping upward,
  Even at a plurality of or all of the intermediate region between the carrier film passing through the doctor blade and being introduced into the inlet of the drying furnace, the upper surfaces of the both end portions are pressed and the both end portions warp upward. Green sheet manufacturing method that prevents Furthermore, the manufacturing method of the green sheet of Claim 5 which presses down the upper surface of the said both ends introduced into the inside of the said drying furnace, and prevents that the said both ends warp upwards.

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