Gravure printing plate and method for manufacturing laminated electronic component

Abstract

The invention provides a gravure printing plate and a method for manufacturing a laminated electronic component, which can prevent linear paste from exceeding the printing range. A gravure printing plate (12) is a cylindrical or cylindrical printing plate for printing paste on a ceramic green sheet, and is provided with a peripheral surface on which one or more printing patterns are provided, each of the one or more printing patterns is provided with a plurality of recesses (42) partitioned by banks (41), and the outer edge of the printing pattern (121) has a rectangular shape having first corners (121c) having a circle at four corners.

Description

Technical Field

[0001] The present disclosure relates to a gravure printing plate used for gravure printing, and a method for producing a laminated electronic component using the gravure printing plate. Background Art

[0002] Conventionally, as described in Japanese Patent Application Publication No. 2012-66559 (Patent Document 1), when a laminated electronic component is manufactured using a gravure printing plate, the gravure printing plate is immersed in a paste tank storing a conductive paste or a dielectric paste, the concave portions provided in the gravure printing plate are filled with the paste, and the paste is transferred to a sheet.

[0003] Prior Art Literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2012-66559 Summary of the invention

[0006] Problem that the invention aims to solve

[0007] However, the printing pattern of the gravure printing plate described in Patent Document 1 has a rectangular shape with sharp corners. Therefore, when the paste is separated from the gravure printing plate, the paste may extend linearly from the corners and adhere to an area outside the printing range.

[0008] The present disclosure has been made in view of the above-mentioned problems, and an object of the present disclosure is to provide a gravure printing plate capable of suppressing linear paste from protruding outside the printing range, and a method for producing a laminated electronic component using the gravure printing plate.

[0009] Technical solutions to solve problems

[0010] The gravure printing plate disclosed in the present invention is a cylindrical or columnar printing plate for printing paste on a ceramic green sheet. The gravure printing plate has a peripheral surface provided with one or more printing patterns. Each of the one or more printing patterns is provided with a plurality of recesses separated by embankments. The outer edge of the printing pattern is a rectangular shape with four corners having a first corner portion with a round shape.

[0011] In the gravure printing plate based on the present disclosure, the outer edge of the concave portion defining the opening surface of the concave portion may also have a rectangular shape with four corners having a second corner portion with a rounded shape. When the radius of curvature of the first corner portion is set to R1 and the radius of curvature of the second corner portion is set to R2, the relationship of R1>R2 may also be satisfied.

[0012] In the gravure printing plate according to the present disclosure, the bank may be provided with a cutout portion for connecting mutually adjacent recessed portions, and the corner of the bank facing the cutout portion may be rounded.

[0013] In the gravure printing plate according to the present disclosure, the bottom surface portion of the concave portion may be formed of a curved surface.

[0014] In the gravure printing plate according to the present disclosure, the depth of the concave portion may be deeper than the depth of the cut portion.

[0015] In the gravure printing plate according to the present disclosure, the bank portion may include an outer bank portion located on the peripheral side of the printed pattern and an inner bank portion located on the inner side of the outer bank portion.

[0016] The method for producing a laminated electronic component according to the present disclosure comprises: a step of transferring a dielectric paste or a conductive paste using the gravure printing plate to form a sheet; a step of forming a laminate including the sheet; and a step of firing the laminate.

[0017] Effects of the Invention

[0018] According to the present disclosure, it is possible to provide a gravure printing plate capable of suppressing linear paste from protruding outside the printing range, and a method for producing a laminated electronic component using the gravure printing plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a diagram showing a gravure printing apparatus including the gravure printing plate according to the first embodiment.

[0020] Figure 2 This is a perspective view showing the intaglio printing plate according to the first embodiment.

[0021] Figure 3 This is a diagram showing an enlarged view of a printing pattern of the gravure printing plate according to the first embodiment.

[0022] Figure 4 It is along Figure 3 A cross-sectional view taken along line IV-IV is shown.

[0023] Figure 5 This is a diagram showing how the paste is peeled off from the concave portions in the gravure printing plate according to the first embodiment.

[0024] Figure 6 This is a diagram showing a production flow of a laminated electronic component using the gravure printing plate according to the first embodiment.

[0025] Figure 7 This is a diagram showing a cross section of a concave portion of a gravure printing plate according to a second embodiment.

[0026] Figure 8 This is a diagram showing an enlarged view of a printing pattern of a gravure printing plate according to the third embodiment.

[0027] Fig. 9 This is a diagram showing an enlarged view of a printing pattern of a gravure printing plate according to a fourth embodiment.

[0028] Description of Reference Numerals

[0029] 10: gravure printing device; 11: support roller; 12, 12A: gravure printing plate; 12p: peripheral surface; 13: scraper; 14: conductive paste; 15: paste groove; 25: dielectric sheet; 30: green sheet; 31: electrode pattern; 41: bank; 42: recess; 42c: second corner; 43: wall portion; 45, 45A: longitudinal bank; 46, 46A: transverse bank; 47, 48: cutting portion; 4 6c, 47c: corners; 121: printed pattern; 121c: 1st corner; 411: top; 421: bottom; 431: 1st wall; 432: 2nd wall; 433: 3rd wall; 434: 4th wall; 451, 461: both ends; C1, C2: center; CL: axial direction; T1, T2: connection position; TL1, TL2: wiring; VL: imaginary line. DETAILED DESCRIPTION

[0030] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the drawings. In the embodiments described below, the same or common parts are denoted by the same reference numerals in the drawings, and their description will not be repeated.

[0031] (Implementation Method 1)

[0032] Figure 1 This is a diagram showing a gravure printing apparatus including the gravure printing plate according to the first embodiment. Figure 2 1 is a perspective view showing a gravure printing plate according to Embodiment 1. Figure 1 as well as Figure 2 , the gravure printing device 10 and the gravure printing plate 12 are described.

[0033] The gravure printing apparatus 10 includes a backup roller 11 , a gravure printing plate 12 , a doctor blade 13 , and a paste tank 15 .

[0034] The support roll 11 and the gravure printing plate 12 are arranged to face each other so as to form a nip portion. The green sheet 30 is passed between the support roll 11 and the gravure printing plate 12 while being sandwiched by the nip portion.

[0035] The support roller 11 has a cylindrical shape or a cylindrical shape. Figure 1 Rotate in the direction of the arrow AR1.

[0036] like Figure 2 As shown, the gravure printing plate 12 has a cylindrical or cylindrical shape. The diameter of the gravure printing plate 12 is, for example, about 10 mm to 400 mm. The width of the gravure printing plate 12 parallel to the axial direction CL is, for example, about 150 mm to 300 mm. A plurality of printing patterns 121 are provided on the gravure printing plate 12. In addition, more than one printing pattern 121 may be provided.

[0037] Again Figure 1 As shown, the gravure printing plate 12 is configured to be able to Figure 1 The gravure printing plate 12 is provided to be rotatable in the direction opposite to the support roll 11 .

[0038] The conductive paste 14 is stored in the paste tank 15. A portion of the gravure printing plate 12 is immersed in the conductive paste 14, and when the gravure printing is performed, the conductive paste 14 is filled in a plurality of recesses 42 (see FIG. Figure 3 )Inside.

[0039] The scraper 13 is disposed on the downstream side of the paste tank 15 and is in contact with the gravure printing plate 12 at a given pressure. The scraper 13 is attached to the gravure printing plate 12 to scrape off excess conductive paste 14.

[0040] Next, when the gravure printing plate 12 holding an appropriate amount of the conductive paste 14 passes through the nip, the electrode pattern 31 corresponding to the printed pattern 121 is printed on the green sheet 30 .

[0041] Figure 3 This is a diagram showing an enlarged view of a printing pattern of the gravure printing plate according to the first embodiment. Figure 4 It is along Figure 3 More specifically, Figure 4 The cross section passes through the central portions C1 and C2 in the circumferential direction of each of the concave portions 42 adjacent to each other in the direction parallel to the axial direction CL and is parallel to the radial direction of the intaglio printing plate 12 and the axial direction CL. Figure 3 as well as Figure 4 , the detailed structure of the gravure printing plate 12 is described.

[0042] like Figure 3 As shown, the outer shape of each of the plurality of printed patterns 121 has a substantially rectangular shape. More specifically, the outer shape of the printed pattern 121 has a rectangular shape having rounded first corners 121 at four corners. In addition, the printed pattern 121 is not limited to a substantially rectangular shape, and can adopt an appropriate shape according to the shape of the electrode pattern 31.

[0043] A plurality of recessed portions 42 partitioned by banks 41 are arranged in each of the plurality of printed patterns 121. The banks 41 are provided in a lattice shape.

[0044] The embankment 41 includes a plurality of longitudinal embankments 45 and a plurality of transverse embankments 46. The plurality of longitudinal embankments 45 each extend in the circumferential direction of the peripheral surface 12p. The plurality of longitudinal embankments 45 are arranged at intervals in a direction parallel to the axial direction CL. The plurality of transverse embankments 46 each extend in a direction parallel to the axial direction CL. The plurality of transverse embankments 46 are arranged at intervals in the circumferential direction.

[0045] The plurality of recesses 42 are arranged in a matrix in a row direction parallel to the circumferential direction and in a column direction parallel to the axial direction. The outer edge of the recess 42 defining the opening surface of the recess 42 has a rectangular shape having rounded second corners 42c at four corners.

[0046] When the curvature radius of the first corner 121c is set to R1 and the curvature radius of the second corner 42c is set to R2, the relationship of R1>R2 is achieved. In addition, the curvature radius can be confirmed by peeling off a part of the peripheral surface 12p of the gravure printing plate 12, cutting off the peeled part and observing it with an optical microscope.

[0047] like Figure 3 as well as Figure 4 As shown, the dike 41 has a top 411 and a wall portion 43. The top 411 is substantially flat. The top 411 is substantially parallel to the opening surface of the recess 42. The wall portion 43 is connected to the bottom portion 421 of the recess 42 and defines the side surface of the recess 42. The wall portion 43 is connected to the periphery of the bottom portion 421 and has an annular shape. When the recess 42 is observed along the depth direction of the recess 42, the periphery of the bottom portion 421 is located at a position closer to the inside than the outer edge of the opening surface of the recess 42. The wall portion 43 has a curved surface shape that bends toward the periphery of the bottom portion 421 as it advances in the depth direction of the recess 42.

[0048] The wall surface portion 43 includes a first wall surface portion 431 and a second wall surface portion 432 that are opposite to each other in a direction parallel to the axial direction CL, and a third wall surface portion 433 and a fourth wall surface portion 434 that are opposite to each other in the circumferential direction. The first wall surface portion 431 and the second wall surface portion 432 are each formed of a curved surface that curves toward the peripheral edge of the bottom surface portion 421 as they advance in the depth direction of the recessed portion 42 as described above. The third wall surface portion 433 and the fourth wall surface portion 434 are each similarly formed of a curved surface that curves toward the peripheral edge of the bottom surface portion 421 as they advance in the depth direction of the recessed portion 42.

[0049] The bottom portion 421 of the recessed portion 42 is formed flat. In a cross section passing through the above-mentioned central portions C1 and C2 and parallel to the radial direction of the gravure printing plate 12 and the above-mentioned axial direction CL, the bottom portion 421 is located on an extension line of a tangent line TL1 of the first wall portion 431 at a connection position T1 between the first wall portion 431 and the bottom portion 421. In addition, in the above-mentioned cross section, the bottom portion 421 is located on an extension line of a tangent line TL2 of the second wall portion 432 at a connection position T2 between the second wall portion 432 and the bottom portion 421.

[0050] In a cross section of the gravure printing plate 12 that passes through the central portion of each of the concave portions 42 adjacent to each other in the circumferential direction in a direction parallel to the axial direction CL and is orthogonal to the axial direction CL, the bottom portion 421 is located on an extension line of a tangent to the third wall portion 433 at a connection position between the third wall portion 433 and the bottom portion 421. In addition, in the cross section, the bottom portion 421 is located on an extension line of a tangent to the fourth wall portion 434 at a connection position between the fourth wall portion 434 and the bottom portion 421.

[0051] The shape of the recessed portion 42 can be formed by adjusting the residence time of the etching solution when etching the peripheral surface 12p of the gravure printing plate 12. For example, the gravure plate can be moved obliquely so that the etching solution stays at a given position of the printed pattern 121 for a long time.

[0052] Figure 5 This is a diagram showing how the paste is peeled off from the concave portions in the gravure printing plate according to the first embodiment.

[0053] like Figure 5 As shown in the figure, the wall portion 43 is formed of a curved surface, and the bottom portion 421 is located on the extension of the tangent line at the connection position with each of the first wall portion 431 to the fourth wall portion 434, so that when the conductive paste 14 in the concave portion 42 is transferred, as shown by the arrow in the figure, the peeling force can be smoothly and continuously applied to the conductive paste 14 from the bottom portion 421 to the top portion 411. As a result, the conductive paste 14 can be smoothly transferred to the green sheet 30. Specifically, more than 60% of the conductive paste 14 filled in the concave portion 42 can be transferred to the green sheet 30, and the amount of the conductive paste 14 remaining in the concave portion 42 can be reduced.

[0054] The remaining amount of the paste can be calculated, for example, as follows. First, the shapes of the ten recesses 42 are measured in advance using a laser displacement meter or the like. Next, the printing pattern 121 is filled with the paste 14, and each of the ten recesses 42 after transfer is measured using a laser displacement meter or the like. Thus, the remaining amount of the paste 14 is calculated by measuring the remaining amount of the paste in each recess 42 and calculating the average value of the ten recesses 42. In addition, the amount of the transferred paste 14 can also be calculated based on the calculated remaining amount of the paste 14.

[0055] As described above, in the gravure printing plate 12 according to the first embodiment, the first corners 121c located at the four corners of the outer edge of the printing pattern 121 are rounded, so when the gravure printing plate 12 is separated from the raw sheet 30, the paste can be cut off from the gravure printing plate 12 along the outer edge of the printing pattern 121. Thus, it is possible to suppress the linear paste from extending outward from the first corners 121c.

[0056] (Verification experiment)

[0057] When printing was performed 100 times (shots) using the gravure printing plate 12 involved in Embodiment 1 and whether the paste adhered to the area outside the printing range was confirmed, the adhesion of the paste to the area outside the printing range was not confirmed. On the other hand, as a comparative example, when printing was performed 100 times using a gravure printing plate having angular corners at the four corners of the outer edge of the printing pattern 121, the adhesion of the paste to the area outside the printing range was confirmed in 13 times.

[0058] (Method for manufacturing laminated electronic component)

[0059] Figure 6 1 is a diagram showing a production flow of a laminated electronic component using the gravure printing plate according to the first embodiment. Figure 6 , a method for manufacturing a stacked electronic component according to Embodiment 1 is described.

[0060] like Figure 6 As shown in FIG. 1 , when manufacturing a laminated ceramic capacitor as a laminated electronic component, first, in step (S1), a green sheet 30 and a conductive paste for internal electrodes are prepared. The green sheet 30 is formed by kneading a ceramic powder represented by barium titanate, a binder, a dispersant, a plasticizer, etc. The conductive paste 14 is a conductive paste kneaded by a conductive powder, a solvent, a binder, and a ceramic powder. The green sheet 30 and the conductive paste 14 can use a known green sheet and conductive paste.

[0061] Next, in step (S2), Figure 1 As shown, the conductive paste 14 for internal electrodes is transferred to the green sheet 30 in a given pattern using the gravure printing plate 12. Thus, the dielectric sheet 25 having the electrode pattern 31 is formed. The gravure printing plate 12 can also be used when transferring the dielectric paste.

[0062] Next, in step (S3), a plurality of dielectric sheets are stacked to produce a stacked sheet. Specifically, a predetermined number of dielectric sheets for the outer layer without an electrode pattern printed thereon are stacked, a dielectric sheet 25 printed with an electrode pattern 31 is sequentially stacked thereon, and a predetermined number of dielectric sheets for the outer layer are stacked thereon.

[0063] Next, in step (S4), a stacked block is produced. Specifically, the stacked sheets are pressed in the stacking direction using a pressing device such as an isostatic press.

[0064] Next, in step (S5), a stacked chip is produced. Specifically, a cutting knife is used to cut the stacked block into a given size to cut out a stacked chip. At this time, the corners and ridges of the stacked chip may be rounded by roller grinding or the like.

[0065] Next, in step (S6), the stacked small pieces are fired. The firing temperature depends on the materials of the dielectric and the electrode pattern, but is, for example, about 900°C to 1300°C.

[0066] Next, in step (S7), external electrodes are formed. For example, by applying a conductive paste for external electrodes to both end faces of the stacked small pieces and sintering, a sintered layer is formed on the two end faces. At this time, the sintering temperature is, for example, 700°C to 900°C. Next, a plating layer is provided on the surface of the sintered layer as required. After the above steps, a stacked electronic component can be manufactured.

[0067] (Implementation Method 2)

[0068] Figure 7 2 is a diagram showing a cross section of a concave portion of a gravure printing plate according to Embodiment 2. Figure 7 , the gravure printing plate 12A involved in embodiment 2 is described.

[0069] like Figure 7 As shown, the gravure printing plate 12A according to the second embodiment is different in shape of the recessed portion 42 (more specifically, the bottom surface portion 421 ) when compared with the gravure printing plate 12 according to the first embodiment. The other structures are substantially the same.

[0070] In Embodiment 2, in addition to the wall surface 43, the bottom surface 421 is also composed of a curved surface. The bottom surface 421 has a shape that is curved toward the center of the recessed portion 42 as it moves toward the depth direction. The curvature radius of the bottom surface 421 may be larger than the curvature radius of the wall surface 43. The curvature radius can be confirmed by peeling off a part of the peripheral surface 12p of the gravure printing plate 12, cutting off the peeled part, and observing it with an optical microscope.

[0071] Even in such a configuration, the gravure printing plate 12A according to Embodiment 2 has substantially the same effects as those of Embodiment 1. Since the bottom surface portion 421 is formed of a curved surface, the conductive paste 14 can be easily separated from the gravure printing plate 12A during transfer.

[0072] Furthermore, by making the curvature radius of bottom surface portion 421 larger than the curvature radius of wall surface portion 43, a peeling force can be more smoothly applied to conductive paste 14. As a result, conductive paste 14 can be transferred to green sheet 30 more smoothly.

[0073] (Implementation 3)

[0074] Figure 8 This is a diagram showing an enlarged view of a printing pattern of a gravure printing plate according to Embodiment 3. Figure 8 , the gravure printing plate involved in embodiment 3 is described.

[0075] like Figure 8 As shown, the gravure printing plate according to the third embodiment is different from the gravure printing plate 12 according to the first embodiment in the printed pattern 121. The other structures are substantially the same.

[0076] In the third embodiment, a plurality of cutouts 47 and 48 are provided on the bank 41. The cutouts 47 and 48 are provided to connect mutually adjacent recesses 42. The depth of the recess 42 is deeper than the depth of the cutouts 47 and 48. The corners 46c and 47c of the bank facing the cutouts 47 and 48 are rounded.

[0077] A plurality of cutout portions 47 are provided on each of the longitudinal bank portions 45. In addition, a single cutout portion 47 may be provided on each of the longitudinal bank portions 45 instead of a plurality of cutout portions.

[0078] The cutouts 47 are provided in the longitudinal bank portion 45 between the adjacent recesses 42 in the direction parallel to the axial direction CL. The cutouts 47 provided in the portions between the plurality of recesses 42 arranged in the axial direction CL may be arranged in a row in the axial direction CL or may be arranged staggered in the circumferential direction.

[0079] A plurality of cutouts 48 are provided on each lateral bank 46. In addition, a single cutout 48 may be provided on each lateral bank 46 instead of a plurality of cutouts.

[0080] The cutouts 48 are provided in the portions of the transverse bank 46 between the adjacent recesses 42 in the direction parallel to the circumferential direction. The cutouts 48 provided in the portions between the plurality of recesses 42 arranged in the circumferential direction may be arranged in the circumferential direction or may be arranged staggered in the direction parallel to the axial direction CL.

[0081] Even when configured as described above, the gravure printing plate according to Embodiment 3 can achieve substantially the same effects as those of Embodiment 1. By providing the plurality of cutouts 47 and 48 , the fluidity of the conductive paste 14 can be improved.

[0082] The conductive paste 14 is transferred from the bank as a starting point, so the number of starting points for transfer can be increased by providing the cutouts 47 and 48. This allows the transfer to be performed evenly within the printed pattern 121, thereby improving printability.

[0083] Furthermore, since the corners 46c and 47c of the bank portions facing the cutout portions 47 and 48 are rounded, it is possible to suppress stringing at the corners 46c and 47c when the transferred intaglio printing plate 12 is separated from the sheet.

[0084] (Implementation 4)

[0085] Fig. 9 This is a diagram showing an enlarged view of a printing pattern of a gravure printing plate according to Embodiment 4. Fig. 9 , the gravure printing plate involved in embodiment 4 is described.

[0086] like Fig. 9 As shown, the gravure printing plate according to the fourth embodiment has a different printing pattern 121 when compared with the gravure printing plate according to the third embodiment. The other structures are substantially the same. In the fourth embodiment, the plurality of cutouts 47 and 48 may be omitted.

[0087] In the fourth embodiment, the bank 41 includes an outer bank located on the peripheral side of the printed pattern 121 and an inner bank located inside the outer bank, and the thickness (width) of the outer bank is smaller than that of the inner bank.

[0088] Specifically, for example, the outer bank portion is a portion of the bank portion 41 located outside the imaginary line VL in the figure. The outer bank portion is composed of, for example, both ends 451 of each longitudinal bank portion 45A in the circumferential direction and both ends 461 of each transverse bank portion 46A in a direction parallel to the axial direction CL.

[0089] The thickness (width W1) of both ends 451 of the longitudinal bank portion 45A is smaller than the thickness (width W3) of a portion 452 of the longitudinal bank portion 45A located between the both ends 451. Similarly, the thickness (width W2) of both ends 461 of the transverse bank portion 46A is smaller than the thickness (width W4) of a portion 462 of the transverse bank portion 46A located between the both ends 461.

[0090] In the case of such a configuration, the gravure printing plate involved in Embodiment 4 also has substantially the same effect as the gravure printing plate involved in Embodiment 3. In addition, since the thickness of the outer bank is thinner than that of the inner bank, the transfer can be promoted at the edge of the electrode pattern 31 during transfer, and blurring of printing can be suppressed.

[0091] (Other Modifications)

[0092] In addition, a groove having a width of 0.01 μm or more and 1 μm or less may be formed on the top 411 of the bank 41 and / or the peripheral surface 12p of the gravure printing plate. The groove portion may extend in a direction parallel to the axial direction CL or in the circumferential direction. By providing the groove portion, it becomes easy to scrape off excess conductive paste 14 with the scraper 13.

[0093] Furthermore, the size of the inner recess 42 in the printed pattern 121 may be smaller than the size of the outer recess 42 in the printed pattern 121. By reducing the inner recess 42, more bank 41 can be formed. The conductive paste 14 is transferred starting from the bank 41, so by arranging more bank 41, the transfer efficiency of the conductive paste 14 can be improved.

[0094] The embodiments disclosed herein are by way of illustration and non-restrictive in all aspects. The scope of the present invention is indicated by the claims, and all modifications within the meaning and scope equivalent to the claims are included.

Claims

1. A gravure printing plate, which is a cylindrical or columnar gravure printing plate for printing paste on a ceramic green sheet, wherein: The gravure printing plate has a peripheral surface provided with one or more printing patterns. Each of the one or more printed patterns is provided with a plurality of recessed portions separated by banks, The outer edge of the printed pattern is a rectangular shape having four rounded first corners.

2. The gravure printing plate according to claim 1, wherein The outer edge of the recessed portion defining the opening surface of the recessed portion has a rectangular shape with four corners having rounded second corners. When the curvature radius of the first corner portion is R1 and the curvature radius of the second corner portion is R2, the relationship of R1>R2 is satisfied.

3. The gravure printing plate according to claim 1, wherein The bank portion is provided with a cut-off portion for connecting mutually adjacent recessed portions. Corners of the bank of a portion facing the cutout portion are rounded.

4. The gravure printing plate according to claim 3, wherein The bottom surface portion of the recessed portion is formed of a curved surface.

5. The gravure printing plate according to claim 3, wherein The depth of the recessed portion is greater than the depth of the cutout portion.

6. The gravure printing plate according to claim 1, wherein The bank portion includes an outer bank portion located on the peripheral side of the printed pattern and an inner bank portion located on the inner side of the outer bank portion. The thickness of the outer bank is smaller than that of the inner bank.

7. A method for manufacturing a laminated electronic component, comprising: A step of forming a sheet by transferring a dielectric paste or a conductive paste using the gravure printing plate according to any one of claims 1 to 6; a step of forming a laminate including the sheet; and A step of firing the laminated body.

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