JP2004266122A - Manufacturing method of ceramic electronic component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a ceramic electronic component capable of suppressing a structural defect caused by exfoliation of a ceramic sheet. <P>SOLUTION: The ceramic sheet 13 with a conductor layer 14 is formed on a carrier film 15. Then the ceramic sheet 13 with the conductor layer 14 is stacked on other ceramic sheet 13 of a support plate 11 together with the carrier film 15, and the upper side is entirely pressed. Then corners of the ceramic sheet 13 acting like separating points between the carrier film 15 and the ceramic sheet 13 are pressed and heated again by a press machine 17 via the carrier film 15, and thereafter the carrier film 15 is exfoliated. Similarly, the ceramic sheets 13 with the conductor layer 14 are stacked to produce a laminated body block 19. Then the block 19 is cut and sintered to form an external electrode. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing a ceramic electronic component such as a multilayer ceramic capacitor.
[0002]
[Prior art]
A method for manufacturing a conventional ceramic capacitor will be described.
[0003]
First, an organic binder or the like is added to ceramic powder containing barium titanate as a main component, kneaded and slurried, and then a ceramic sheet is formed on a carrier film using a doctor blade method or the like.
[0004]
Next, a metal paste is screen-printed on the ceramic sheet to prepare a plurality of rectangular ceramic sheets with conductor layers.
[0005]
Next, a predetermined number of ceramic sheets, a ceramic sheet with a conductor layer, and a ceramic sheet are laminated on the support plate in this order via an adhesive sheet. The lamination of the ceramic sheet and the ceramic sheet with a conductor layer is performed by arranging the carrier film side upward, pressing the entire surface with a rigid body, and repeating the step of peeling the carrier film.
[0006]
Next, a plurality of ceramic sheets with a conductor layer are similarly laminated thereon with the carrier film side facing upward, and after pressing, the carrier film is peeled off.
[0007]
Thereafter, similarly, the lamination of the ceramic sheet, the press bonding, and the peeling of the carrier film are repeated to produce a laminate.
[0008]
Next, the upper and lower portions of the laminate are pressed and sandwiched by a press plate, integrated, cut into a desired shape, and separated from the support plate to form a laminate of individual pieces.
[0009]
Thereafter, the laminate is fired to form external electrodes, thereby obtaining a multilayer ceramic capacitor.
[0010]
As prior art document information related to the invention of this application, for example, Patent Document 1 is known.
[0011]
[Patent Document 1]
JP-A-5-198459
[Problems to be solved by the invention]
According to the above method, a step occurs due to the presence or absence of the conductor layer at the outer peripheral portion of the laminate, which is the starting point of the carrier film peeling, and the pressure cannot be sufficiently applied. As a result, when the carrier film is peeled, there is a problem that the ceramic sheet is peeled off from the laminate and folded or cut, thereby causing a structural defect.
[0013]
Therefore, an object of the present invention is to provide a method for manufacturing a ceramic electronic component that can suppress structural defects due to peeling of a ceramic sheet.
[0014]
[Means for Solving the Problems]
The invention according to claim 1 of the present invention includes, in particular, a first step of laminating a ceramic sheet with a conductor layer formed on a carrier film on another ceramic sheet with a conductor layer and pressing the entire surface from above the carrier film; And a second step of repressing a part of the outer periphery of the ceramic sheet with the conductor layer from above the carrier film, and a third step of peeling off the carrier film from the repressed portion as a starting point. The ceramic sheet, which is the starting point of separation between the carrier film and the ceramic sheet, has a sufficient adhesive strength and can suppress the occurrence of structural defects due to the separation of the ceramic sheet when the carrier film is separated.
[0015]
In the invention according to claim 2 of the present invention, in particular, heating is also performed in the second step, and the ceramic sheet is softened by heating, and sufficient pressure can be applied between the ceramic sheets even if the pressure is shorter than normal temperature. High adhesive strength and improve productivity.
[0016]
In the invention according to claim 3 of the present invention, in particular, the pressing in the second step is performed using an elastic body, and even when there is a step due to the presence or absence of the conductor layer in the pressing portion, the pressing between the ceramic sheets is performed. Sufficient adhesive strength.
[0017]
According to the invention described in claim 4 of the present invention, in particular, in the second step, pressure is applied so that the side surfaces of the ceramic sheet are covered with the elastic body. Adhesion between the sheets is ensured, and peeling of the ceramic sheet can be suppressed when the carrier film is peeled.
[0018]
In the invention according to claim 5 of the present invention, in particular, the pressurization in the first step is performed by a rigid body, so that the elongation of the ceramic sheet can be suppressed, and the occurrence of structural defects can be suppressed.
[0019]
In the invention according to claim 6 of the present invention, in particular, the pressing force in the second step is made smaller than the pressing force in the first step. The transfer failure of the upper ceramic sheet, which is caused by excessively denting than the portion, can be suppressed.
[0020]
The invention as set forth in claim 7 of the present invention is particularly one in which, after the second step, the carrier film is separated after cooling, and the resin contained in the conductor layer and the ceramic sheet is cured, The film can be easily peeled off.
[0021]
The invention according to claim 8 of the present invention presses the entire outer periphery of the ceramic sheet particularly in the second step. Even if the ceramic sheet is thin, the carrier film can be peeled while suppressing the peeling of the ceramic sheet. .
[0022]
The invention according to claim 9 of the present invention is, in particular, laminating a ceramic sheet with a conductor layer formed on a carrier film on another ceramic sheet with a conductor layer, and from the carrier film on the outer periphery of the ceramic sheet with a conductor layer. A first step of partially pressing, and then a second step of pressing the entire surface of the ceramic sheet with a conductor layer from above the carrier film, and then starting with the part pressed in the first step as a starting point. The method includes a third step of peeling the carrier film, and has a sufficient adhesive strength between a portion of the ceramic sheet serving as a starting point of separation of the carrier film and the ceramic sheet. Generation of structural defects can be suppressed.
[0023]
In the invention according to claim 10 of the present invention, in particular, heating is also performed in the first step, and the ceramic sheet is softened by heating, and sufficient pressure can be applied between the ceramic sheets even with a short pressurization compared with normal temperature. High adhesive strength and improve productivity.
[0024]
In the invention according to claim 11 of the present invention, in particular, the pressing in the first step is performed by using an elastic body, and even if there is a step due to the presence or absence of the conductor layer in the pressing portion, the pressing between the ceramic sheets is performed. Sufficient adhesive strength.
[0025]
According to the twelfth aspect of the present invention, in particular, in the first step, the pressure is applied so that the side surfaces of the ceramic sheet are also covered with the elastic body. And the peeling of the ceramic sheet when the carrier film is peeled can be suppressed.
[0026]
In the invention according to claim 13 of the present invention, in particular, the pressurization in the second step is performed by a rigid body, so that the elongation of the ceramic sheet can be suppressed, and the occurrence of structural defects can be suppressed.
[0027]
In the invention according to claim 14 of the present invention, in particular, the pressing force in the second step is larger than the pressing force in the first step, and the portion pressurized in the first step is another part. It is possible to suppress transfer failure of the upper ceramic sheet, which is caused by excessively denting than the portion.
[0028]
In the invention according to claim 15 of the present invention, in particular, after the second step, the third step is performed after the cooling step, and the resin contained in the conductor layer and the ceramic sheet is cured, The carrier film can be easily peeled off.
[0029]
In the invention according to claim 16 of the present invention, in particular, in the first step, the entire outer periphery of the ceramic sheet is pressed. Even if the ceramic sheet is thin, the carrier film is separated while suppressing the separation of the ceramic sheet. it can.
[0030]
BEST MODE FOR CARRYING OUT THE INVENTION
(Embodiment 1)
Hereinafter, the first embodiment of the present invention will be described with reference to the first embodiment.
[0031]
1 to 3 are cross-sectional views for explaining a laminated block manufacturing process in the first embodiment, where 11 is a support plate, 12 is an adhesive sheet, 13 is a ceramic sheet, 14 is a conductor layer, and 15 is a carrier film. , 16 and 17 are press machines, 17a is an elastic body, 18 is a carrier film peeling device, and 19 is a laminate block.
[0032]
FIG. 4 is a partially cutaway perspective view of the multilayer ceramic capacitor according to the present embodiment, in which 31 is a ceramic layer, and 32 is an external electrode.
[0033]
First, a large number of rectangular conductor layers 14 are formed on a carrier film 15 via a release layer (not shown), and dried. The conductor layer 14 is formed by screen printing a metal paste in which a solvent such as a polyvinyl butyral-based organic binder, an aliphatic naphtha, an aromatic naphtha, and terpineol is mixed with a metal powder containing nickel as a main component.
[0034]
Next, a ceramic powder mainly composed of barium titanate is kneaded with a polyvinyl butyral-based organic binder, dibutyl phthalate as a plasticizer, and butyl acetate as a solvent to form a slurry. A quadrangular ceramic sheet 13 serving as a ceramic layer 31 is formed on the carrier film 15 on which the 14 is formed.
[0035]
In the ceramic sheet 13 with the conductor layer 14 thus manufactured, the thickness of the ceramic sheet 13 is about 10 μm, and the thickness of the conductor layer 14 is about 2.5 μm.
[0036]
Next, an adhesive sheet 12 having adhesiveness on both sides is attached on the support plate 11, and 20 ceramic sheets 13 on which the conductor layer 14 is not formed are laminated thereon. The adhesive force of the adhesive sheet 12 is necessary to such an extent that the ceramic sheet 13 and the support plate 11 are not separated. However, since it is necessary to separate the laminate block 19 after cutting, it has a function to lose the adhesiveness with the laminate block 19 at a temperature higher than the heating temperature at the time of producing the laminate block 19.
[0037]
Then, the ceramic sheet 13 with the conductor layer 14 is laminated together with the carrier film 15 on the laminated ceramic sheet 13 as shown in FIG. Press and heat.
[0038]
Next, as shown in FIG. 1, the corner of the ceramic sheet 13, which is the separation starting point between the carrier film 15 and the ceramic sheet 13, is pressed again at 1 MPa and 100 ° C. for 1 second by the press 17 via the carrier film 15. Heat.
[0039]
Next, after the organic material such as the binder contained in the conductor layer 14 and the ceramic sheet 13 is cured so that the carrier film 15 can be easily separated, the carrier film 15 is pressed by a press 17 as shown in FIG. The carrier film 15 is peeled while the portion (the corner of the ceramic sheet 13) is attached to the peeling device 18 and pulled up toward the facing corner. By peeling from the corner, the stress applied to the ceramic sheet 13 can be reduced, and peeling and damage can be suppressed.
[0040]
After that, similarly, 200 ceramic sheets 13 with the conductor layer 14 are laminated, and subsequently, 20 ceramic sheets 13 without the conductor layer 14 are laminated to obtain the laminate block 19.
[0041]
Next, the laminate block 19 is surely integrated by heating and pressing, and then cut to obtain a laminate in which the conductor layer 14 is exposed on both end surfaces.
[0042]
Then, the adhesive sheet 12 is heated to 150 ° C. to lose the adhesiveness, and the laminate is separated from the adhesive sheet 12.
[0043]
Next, the laminate is heat-treated in nitrogen gas to remove the binder, and then heated to 1300 ° C. in a mixed gas atmosphere of nitrogen and hydrogen in which nickel of the conductor layer 14 is not excessively oxidized. , To obtain a sintered body.
[0044]
Next, the outer peripheral surface of the sintered body is polished to completely expose the conductor layer 14 on both end surfaces. Subsequently, an electrode paste containing copper as a main component is applied to both end surfaces of the sintered body. Baking is performed in a nitrogen atmosphere at ℃.
[0045]
Next, nickel plating and solder plating are performed thereon to form external electrodes 32, and the multilayer ceramic capacitor shown in FIG. 4 is manufactured.
[0046]
The internal structure of the multilayer ceramic capacitor of the first embodiment was evaluated by evaluating the electrical characteristics and observing the cross section with a microscope. As a result, there was almost no occurrence of structural defects such as delamination, and the electrical characteristics were good.
[0047]
(Embodiment 2)
Hereinafter, a second embodiment of the present invention will be described with reference to FIG.
[0048]
The difference from the first embodiment is that the thickness of the ceramic sheet 13 used is about 5 μm, which is half the thickness of the first embodiment, that is, the strength of the ceramic sheet 13 is small. It is.
[0049]
First, a ceramic sheet 13 and a ceramic sheet 13 with a conductor layer 14 are prepared in the same manner as in the first embodiment.
[0050]
Next, 20 ceramic sheets 13 are laminated on the support plate 11 with the adhesive sheet 12 interposed therebetween, and the ceramic sheet 13 with the conductor layer 14 is laminated thereon as shown in FIG. Then, the entire ceramic sheet 13 is pressed and heated at 10 MPa and 80 ° C. for 1 second by the press 16 from above.
[0051]
Next, not only the portion serving as the separation starting point of the carrier film 15 but also the entire outer periphery of the ceramic sheet 13 is pressed and heated again at 1 MPa and 100 ° C. for 1 second by a press having a frame-shaped elastic pressing portion.
[0052]
Next, the carrier film 15 is peeled off in the same manner as in the first embodiment.
[0053]
On this, 200 ceramic sheets 13 with the conductor layer 14 on the carrier film 15 are similarly laminated.
[0054]
Further, 20 ceramic sheets 13 are stacked thereon to obtain a laminate block 19.
[0055]
Hereinafter, similarly, the multilayer ceramic capacitor shown in FIG. 4 is obtained.
[0056]
Similarly to the first embodiment, the multilayer ceramic capacitor of the present embodiment was free from structural defects and cutting defects due to peeling of the ceramic sheet 13.
[0057]
In the first and second embodiments, first, the entire surface of the ceramic sheet 13 is pressurized to remove the air in the laminate block 19, and then the separation starting point of the carrier film 15 is pressurized. As a result, it is possible to suppress the air from remaining in the laminate block 19.
[0058]
(Embodiment 3)
A third embodiment of the present invention will be described with reference to a third embodiment.
[0059]
The difference from the first embodiment is a lamination process of the ceramic sheet 13 and the ceramic sheet 13 with the conductor layer 14. Other than that, the description is omitted because it is the same.
[0060]
First, 200 ceramic sheets 13 are laminated on the support plate 11 via the adhesive sheet 12.
[0061]
Next, the ceramic sheet 13 with the conductor layer 14 is laminated thereon together with the carrier film 15, and as shown in FIG. 1, the corners of the ceramic sheet 13 serving as separation starting points of the carrier film 15 and the ceramic sheet 13 are separated by the carrier film 15. And pressurized and heated at 100 ° C. for 1 second at 1 MPa by a press machine 17.
[0062]
Next, as shown in FIG. 2, the entire surface of the ceramic sheet 13 is pressed and heated at 10 MPa and 80 ° C. for 1 second by the press 16 from above.
[0063]
Then, the carrier film 15 is peeled off as described in the first embodiment.
[0064]
Similarly, 200 ceramic sheets 13 with the conductor layer 14 are laminated, and subsequently 20 ceramic sheets 13 are laminated to obtain a laminate block 19.
[0065]
Subsequently, a multilayer ceramic capacitor is obtained in the same manner as in the first embodiment.
[0066]
This multilayer ceramic capacitor also had almost no occurrence of structural defects such as delamination, and also had good electrical characteristics.
[0067]
In the third embodiment as well, since only the corners of the ceramic sheet 13 are pressed and then the entire surface is pressed, it is possible to suppress the air from remaining in the laminate block 19.
[0068]
(Embodiment 4)
A fourth embodiment of the present invention will be described with reference to a fourth embodiment.
[0069]
The difference from the third embodiment is that the thickness of the ceramic sheet 13 to be used is about 5 μm, which is half the thickness of the first embodiment, that is, the ceramic sheet 13 having a small strength is used. It is.
[0070]
First, in the same manner as in the first embodiment, a ceramic sheet 13 with a conductor layer 14 is prepared.
[0071]
Next, 20 ceramic sheets 13 are laminated on the adhesive sheet 12 provided on the support plate 11.
[0072]
Next, the ceramic sheet 13 with the conductor layer 14 is laminated thereon together with the carrier film 15, and the entire outer periphery of the ceramic sheet 13 including the part that becomes the separation starting point between the carrier film 15 and the ceramic sheet 13 is framed through the carrier film 15. And pressurizing and heating at 1 MPa and 100 ° C. for 1 second by a press having an elastic pressing portion.
[0073]
Thereafter, the entire ceramic sheet 13 is pressed and heated from the upper surface of the carrier film 15 at 10 MPa and 80 ° C. for 1 second by the press machine 16.
[0074]
Next, after cooling the resin in the ceramic sheet 13 to a certain degree, the carrier film 15 is peeled off as described in the first embodiment. Then, 20 ceramic sheets 13 on the carrier film 15 are similarly laminated on the ceramic sheet 13.
[0075]
Hereinafter, similarly, the multilayer ceramic capacitor shown in FIG. 4 is obtained.
[0076]
Similarly to the first embodiment, the multilayer ceramic capacitor of the present embodiment was free from structural defects and cutting defects due to peeling of the ceramic sheet 13.
[0077]
In the fourth embodiment, first, the entire outer periphery of the ceramic sheet 13 is pressurized, and then the entire surface is pressurized. Therefore, there is a possibility that air remains in the laminate block 19. Since this air can cause structural defects, it is desirable to prevent air from remaining in the multilayer block 19 when the entire outer periphery is pressurized.
[0078]
Further, when the ceramic sheet 13 is thin and the strength is small as in the second and fourth embodiments, if the pressurized portion is only the corner which is the starting point of peeling, the two sides of the ceramic sheet 13 constituting this corner are Easy to damage. For this reason, there is a possibility that the broken piece may fall on the carrier film 15 in the peeling direction, that is, on the laminate block 19. However, even if the other two sides may be damaged, the carrier film 15 is not likely to fall on the laminate block 19 because the peeling direction of the carrier film 15 is outside the laminate block 19. . Therefore, it is preferable to press the outer periphery including two sides of the ceramic sheet 13 constituting at least the corner portion serving as the peeling starting point.
[0079]
Furthermore, static electricity is generated on the surface of the laminate block 19 when the carrier film 15 is peeled off. Therefore, when the ceramic sheet 13 is damaged, the pieces may be attracted by the static electricity and fall on the laminate block 19. Therefore, more preferably, the entire outer periphery of the ceramic sheet 13 is pressurized to improve the adhesive strength between the ceramic sheets 13 and suppress damage to the ceramic sheet 13.
[0080]
Pressing the entire outer periphery of the ceramic sheet 13 as in the second and fourth embodiments has a remarkable effect particularly on the ceramic sheet 13 having a thickness of 5 μm or less.
[0081]
In each of the above embodiments, the pressing of the corners or the outer periphery of the ceramic sheet 13 is performed by an elastic body, but may be performed by a rigid body. However, it is desirable to use an elastic body because it absorbs steps due to the presence or absence of the conductor layer 14 and can provide sufficient adhesiveness between the ceramic sheets 13. Further, even if the ceramic sheet 13 is displaced by pressing with the elastic body, the elastic body 17a also covers the side surface of the laminate block 19 and presses as shown in FIG. Damage can be suppressed.
[0082]
Further, when the entire surface of the ceramic sheet 13 and the ceramic sheet 13 with the conductor layer 14 are pressed, the pressing is performed by a rigid body. If there is a heat capacity, it may be performed with an elastic body. However, in the case of pressing the entire surface, it is preferable that the pressing be performed with a rigid body because pressing with an elastic body may cause elongation of the ceramic sheet 13 or the conductor layer 14.
[0083]
The pressurization may be performed at once or may be performed a plurality of times. By performing the pressing twice or more, the pressing can be performed at a lower temperature and a lower pressure than in the conventional single pressing, and the deformation and damage of the laminate can be reduced.
[0084]
In addition, when the peeling start point of the carrier film is pressurized (partial pressurization), the temperature of the laminate block 19 is higher and the pressure is lower than in the case of pressurizing the entire surface.
[0085]
This is because the partial pressure focuses on heating to further improve the adhesiveness. Specifically, the organic substances contained in the laminated ceramic sheets 13 are softened within the pressing time. However, it is necessary to set the temperature so that the ceramic sheet 13 and the conductor layer 14 are not excessively deformed. On the other hand, if the pressure is too high, the pressurized portion is significantly deformed, so that it is not possible to accurately laminate the ceramic sheet 13 with the conductor layer 14 to be laminated later.
[0086]
The pressing of the starting point of separation of the carrier film 15 was performed at all times when the ceramic sheet 13 and the ceramic sheet 13 with the conductor layer 14 were laminated. There is no need to perform this step if adhesiveness can be ensured. Heating during pressurization is not always necessary depending on the properties of the ceramic sheet 13.
[0087]
Further, first, the conductor layer 14 was formed on the carrier film 15, and then the ceramic sheet 13 was formed by forming the ceramic sheet 13. However, the ceramic sheet 13 was formed on the carrier film 15. The same effect can be obtained when the conductor layer 14 is manufactured by the above method.
[0088]
In each of the above embodiments, a multilayer ceramic capacitor has been described as an example. However, similar effects can be obtained in ceramic electronic components such as a multilayer varistor, a multilayer ceramic substrate, and a multilayer inductor.
[0089]
【The invention's effect】
As described above, the present invention can provide a method of manufacturing a ceramic electronic component that can suppress structural defects due to peeling of a ceramic sheet during lamination.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a laminated block manufacturing process according to Embodiments 1 and 3 of the present invention. FIG. 2 is a cross-sectional view illustrating a laminated block manufacturing process according to Embodiments 1 to 4 of the present invention. FIG. 3 is a cross-sectional view for explaining a laminated body block manufacturing process according to the first to fourth embodiments of the present invention; FIG. Perspective view [Description of reference numerals]
DESCRIPTION OF SYMBOLS 11 Support plate 12 Adhesive sheet 13 Ceramic sheet 14 Conductive layer 15 Carrier film 16 Press machine 17 Press machine 17a Elastic body 18 Peeling device 19 Laminate block 31 Ceramic layer 32 External electrode

Claims (16)

A first step of laminating a ceramic sheet with a conductor layer formed on a carrier film on another ceramic sheet with a conductor layer, and pressing the entire surface from above the carrier film; A second step of repressing a part of the outer periphery of the sheet, a third step of peeling the carrier film from the repressed part as a starting point, and the third step from the first step as desired. A method for manufacturing a ceramic electronic component, comprising: a fourth step of repeatedly producing a laminate, and a fifth step of firing the laminate. The method for manufacturing a ceramic electronic component according to claim 1, wherein heating is also performed in the second step. 2. The method according to claim 1, wherein the pressing in the second step is performed using an elastic body. 4. The method for manufacturing a ceramic electronic component according to claim 3, wherein in the second step, pressure is applied so that the side surface of the ceramic sheet is also covered with the elastic body. The method for manufacturing a ceramic electronic component according to claim 1, wherein the pressing in the first step is performed by a rigid body. 2. The method for manufacturing a ceramic electronic component according to claim 1, wherein the pressing force in the second step is smaller than the pressing force in the first step. The method for manufacturing a ceramic electronic component according to claim 1, wherein the third step is performed after the cooling step after the second step. 2. The method for manufacturing a ceramic electronic component according to claim 1, wherein the entire outer periphery of the ceramic sheet is pressed in the second step. A first step of laminating a ceramic sheet with a conductor layer formed on a carrier film on another ceramic sheet with a conductor layer, and pressing a part of the periphery of the ceramic sheet with a conductor layer from above the carrier film, A second step of pressing the entire surface of the ceramic sheet with a conductor layer from above the carrier film, a third step of peeling off the carrier film starting from the portion pressed in the first step, A method for manufacturing a ceramic electronic component, comprising: a fourth step of repeating the steps from step 3 to the desired number of times to produce a laminate; and a fifth step of firing the laminate. The method for manufacturing a ceramic electronic component according to claim 9, wherein heating is also performed in the first step. The method according to claim 9, wherein the pressing in the first step is performed using an elastic body. The method for manufacturing a ceramic electronic component according to claim 11, wherein in the first step, pressure is applied so that a side surface of the ceramic sheet is also covered with the elastic body. The method for manufacturing a ceramic electronic component according to claim 9, wherein the pressing in the second step is performed by a rigid body. The method for manufacturing a ceramic electronic component according to claim 9, wherein the pressing force in the second step is larger than the pressing force in the first step. The method according to claim 9, wherein the third step is performed after the cooling step after the second step. The method for manufacturing a ceramic electronic component according to claim 9, wherein the entire outer periphery of the ceramic sheet is pressed in the first step.

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