Gravure printing plate and method for manufacturing laminated electronic component

Abstract

To provide a gravure printing plate capable of suppressing threadlike paste from protruding beyond a printing area.SOLUTION: A gravure printing plate 12 is a cylindrical or columnar printing plate for printing paste onto a ceramic green sheet, and includes a circumferential surface on which one or more printing patterns are provided. Each of the one or more printing patterns comprises a plurality of recesses 42 arranged and partitioned by bank portions 41. The outer edge of a printing pattern 121 has a rectangular shape with first corner portions 121c rounded at the four corners.SELECTED DRAWING: Figure 3

Description

[Technical field]

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

[0002] Conventionally, as described in JP 2012-66559 A (Patent Document 1), when manufacturing laminated electronic components using a gravure printing plate, the gravure printing plate is immersed in a paste tank containing a conductive paste or a dielectric paste, the recesses in the gravure printing plate are filled with the paste, and the paste is transferred to a sheet. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-66559 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the printing pattern of the gravure printing plate described in Patent Document 1 has a rectangular shape with sharp corners, which means that when the paste leaves the gravure printing plate, the paste may stretch like threads from the corners and adhere to areas outside the printing range.

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and an object of the present disclosure is to provide a gravure printing plate capable of preventing thread-like paste from spilling outside the printing area, and a method for manufacturing a laminated electronic component using the gravure printing plate. [Means for solving the problem]

[0006] A gravure printing plate according to the present disclosure is a cylindrical or columnar printing plate for printing a paste onto a ceramic green sheet. The gravure printing plate has a peripheral surface on which one or more printing patterns are provided. Each of the one or more printing patterns has a plurality of recesses separated by banks. The outer edge of the printing pattern is rectangular in shape and has first corners with rounded corners.

[0007] In the gravure printing plate according to the present disclosure, the outer edge of the recess that defines the opening of the recess may have a rectangular shape having second corners with rounded corners. When the radius of curvature of the first corners is R1 and the radius of curvature of the second corners is R2, the relationship R1>R2 may be satisfied.

[0008] In the gravure printing plate according to the present disclosure, the bank portion may be provided with a notch that connects adjacent recesses to each other. Corners of the bank portion facing the notch may be rounded.

[0009] In the gravure printing plate according to the present disclosure, the bottom surface of the recess may be configured as a curved surface.

[0010] In the gravure printing plate according to the present disclosure, the depth of the recess may be greater than the depth of the cutout.

[0011] In a gravure printing plate based on the present disclosure, the bank portion may include an outer bank portion located on the peripheral side of the printing pattern, and an inner bank portion located more inward than the outer bank portion.

[0012] The method for manufacturing a laminated electronic component based on the present disclosure includes the steps of transferring a dielectric paste or a conductive paste using the gravure printing plate to form a sheet, forming a laminate including the sheet, and firing the laminate. Effect of the Invention

[0013] According to the present disclosure, it is possible to provide a gravure printing plate capable of preventing thread-like paste from spilling out of a printing area, and a method for manufacturing a laminated electronic component using the gravure printing plate. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a diagram showing a gravure printing apparatus equipped with a gravure printing plate according to a first embodiment. [Diagram 2] FIG. 1 is a perspective view showing a gravure printing plate according to a first embodiment. [Diagram 3] FIG. 2 is an enlarged view showing a printing pattern of the gravure printing plate according to the first embodiment. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV shown in FIG. [Diagram 5] 4 is a diagram showing a state in which paste is peeled off from recesses in the gravure printing plate according to the first embodiment. FIG. [Figure 6] 5 is a diagram showing a manufacturing flow for manufacturing a laminated electronic component using the gravure printing plate according to the first embodiment. FIG. [Figure 7] FIG. 11 is a diagram showing a cross section of a recessed portion of a gravure printing plate according to a second embodiment. [Figure 8] FIG. 11 is an enlarged view showing a printing pattern of a gravure printing plate according to a third embodiment. [Figure 9] FIG. 11 is an enlarged view showing a printing pattern of a gravure printing plate according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, 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 characters in the drawings, and the description thereof will not be repeated.

[0016] (Embodiment 1) Fig. 1 is a diagram showing a gravure printing apparatus equipped with a gravure printing plate according to embodiment 1. Fig. 2 is a perspective view showing the gravure printing plate according to embodiment 1. A gravure printing apparatus 10 and a gravure printing plate 12 will be described with reference to Figs. 1 and 2.

[0017] The gravure printing apparatus 10 includes a backup roll 11 , a gravure printing plate 12 , a blade 13 , and a paste tank 15 .

[0018] The backup roll 11 and the gravure printing plate 12 are disposed opposite each other so as to form a nip portion. The green sheet 30 passes between the backup roll 11 and the gravure printing plate 12 so as to be sandwiched in the nip portion.

[0019] The backup roll 11 has a columnar or cylindrical shape and is provided so as to be rotatable in the direction of an arrow AR1 in FIG.

[0020] As shown in Fig. 2, the gravure printing plate 12 has a columnar 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. The gravure printing plate 12 has a plurality of printing patterns 121 provided thereon. It is sufficient that one or more printing patterns 121 are provided.

[0021] As shown in Figure 1 again, the gravure printing plate 12 is provided so as to be rotatable in the direction AR2 in Figure 1. The gravure printing plate 12 is provided so as to be rotatable in the opposite direction to the backup roll 11.

[0022] Conductive paste 14 is stored in paste tank 15. A portion of gravure printing plate 12 is immersed in conductive paste 14, and when gravure printing is performed, the plate is rotated in the direction AR2 in the drawing, so that the conductive paste 14 fills a plurality of recesses 42 (see FIG. 3), which will be described later.

[0023] The blade 13 is disposed downstream of the paste tank 15, and is in contact with the gravure printing plate 12 with a predetermined pressure. The blade 13 scrapes off the excess conductive paste 14 adhering to the gravure printing plate 12.

[0024] Subsequently, when the gravure printing plate 12 holding an appropriate amount of conductive paste 14 passes through the nip portion, an electrode pattern 31 corresponding to the printing pattern 121 is printed on the green sheet 30 .

[0025] Fig. 3 is an enlarged view of the printing pattern of the gravure printing plate according to embodiment 1. Fig. 4 is a cross-sectional view taken along line IV-IV shown in Fig. 3. More specifically, Fig. 4 is a cross-section passing through central portions C1 and C2 in the circumferential direction of each of recesses 42 adjacent to each other in a direction parallel to the axial direction CL, and parallel to the radial direction of gravure printing plate 12 and the axial direction CL. The detailed structure of gravure printing plate 12 will be described with reference to Figs. 3 and 4.

[0026] 3, the outer shape of each of the multiple printed patterns 121 is substantially rectangular. More specifically, the outer shape of the printed patterns 121 is a rectangle having first corners 121 that are rounded at the four corners. Note that the printed patterns 121 are not limited to a substantially rectangular shape, and an appropriate shape can be adopted depending on the shape of the electrode pattern 31.

[0027] Each of the plurality of print patterns 121 has a plurality of recesses 42 separated by banks 41. The banks 41 are provided in a lattice pattern.

[0028] The bank portion 41 includes a plurality of vertical bank portions 45 and a plurality of horizontal bank portions 46. Each of the plurality of vertical bank portions 45 extends in the circumferential direction of the peripheral surface 12p. The plurality of vertical bank portions 45 are arranged side by side at intervals in a direction parallel to the axial direction CL. Each of the plurality of horizontal bank portions 46 extends in a direction parallel to the axial direction CL. The plurality of horizontal bank portions 46 are arranged side by side at intervals in the circumferential direction.

[0029] The recesses 42 are arranged in a matrix, for example, with a row direction parallel to the circumferential direction and a column direction parallel to the axial direction. The outer edge of the recess 42 that defines the opening surface of the recess 42 has a rectangular shape with second corners 42c that are rounded at the four corners.

[0030] If the radius of curvature of first corner 121C is R1 and the radius of curvature of second corner 42c is R2, then the relationship is R1>R2. Note that the radius of curvature can be confirmed by peeling off a portion of peripheral surface 12p of gravure printing plate 12, cutting the peeled off portion, and observing it under an optical microscope.

[0031] As shown in FIG. 3 and FIG. 4, the bank portion 41 has a top portion 411 and a wall portion 43. The top portion 411 is configured to be substantially flat. The top portion 411 is substantially parallel to the opening surface of the recess 42. The wall portion 43 is connected to the bottom surface 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 surface portion 421 and has an annular shape. When the recess 42 is viewed along the depth direction of the recess 42, the periphery of the bottom surface portion 421 is located inside the outer edge of the opening surface of the recess 42. The wall portion 43 has a curved shape that curves toward the periphery of the bottom surface portion 421 as it progresses in the depth direction of the recess 42.

[0032] The wall surface portion 43 has a first wall surface portion 431 and a second wall surface portion 432 that face 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 face each other in the circumferential direction. As described above, each of the first wall surface portion 431 and the second wall surface portion 432 is configured with a curved surface that curves toward the periphery of the bottom surface portion 421 as it progresses in the depth direction of the recessed portion 42. Similarly, each of the third wall surface portion 433 and the fourth wall surface portion 434 is configured with a curved surface that curves toward the periphery of the bottom surface portion 421 as it progresses in the depth direction of the recessed portion 42.

[0033] The bottom surface portion 421 of the recess 42 is configured to be flat. In a cross section passing through the above-mentioned central portions C1, C2 and parallel to the radial direction of the gravure printing plate 12 and the above-mentioned axial direction CL, the bottom surface portion 421 is located on an extension line of a tangent line TL1 of the first wall surface portion 431 at a connection position T1 between the first wall surface portion 431 and the bottom surface portion 421. In addition, in the above cross section, the bottom surface portion 421 is located on an extension line of a tangent line TL2 of the second wall surface portion 432 at a connection position T2 between the second wall surface portion 432 and the bottom surface portion 421.

[0034] In a cross section of the gravure printing plate 12 that passes through a center in a direction parallel to the axial direction CL of each of the circumferentially adjacent recesses 42 and is perpendicular to the axial direction CL, the bottom surface portion 421 is located on an extension of a tangent to the third wall surface portion 433 at a connection position between the third wall surface portion 433 and the bottom surface portion 421. Also, in the cross section, the bottom surface portion 421 is located on an extension of a tangent to the fourth wall surface portion 434 at a connection position between the fourth wall surface portion 434 and the bottom surface portion 421.

[0035] The shape of the recesses 42 described above can be achieved by adjusting the residence time of the etching solution when etching the peripheral surface 12p of the gravure printing plate 12. For example, a method can be adopted in which the gravure plate is moved obliquely so that the etching solution remains at a predetermined position of the printing pattern 121 for a long time.

[0036] FIG. 5 is a diagram showing a state in which paste is peeled off from recesses in the gravure printing plate according to the first embodiment.

[0037] 5, the wall surface portion 43 is formed of a curved surface, and the bottom surface portion 421 is located on an extension of the tangent line at the connection position with each of the first wall surface portion 431 to the fourth wall surface portion 434. Therefore, when the conductive paste 14 in the recess 42 is transferred, as shown by the arrow in the figure, a peeling force can be applied to the conductive paste 14 smoothly and continuously from the bottom surface portion 421 to the top portion 411. This allows the conductive paste 14 to be smoothly transferred to the green sheet 30. Specifically, 60% or more of the conductive paste 14 filled in the recess 42 can be transferred to the green sheet 30, and the amount of conductive paste 14 remaining in the recess 42 can be reduced.

[0038] The remaining amount of 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 print pattern 121 is filled with paste 14, and each of the ten recesses 42 after transfer is measured using a laser displacement meter or the like. In this way, the remaining amount of paste in each recess 42 is measured, and the remaining amount of paste 14 is calculated by calculating the average value of the ten recesses. Furthermore, the amount of transferred paste 14 can also be calculated based on the calculated remaining amount of paste 14.

[0039] 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 that when the gravure printing plate 12 is pulled away from the green sheet 30, the paste can be separated from the gravure printing plate 12 along the outer edge of the printing pattern 121. This makes it possible to prevent thread-like paste from extending outward from the first corners 121c.

[0040] (Verification experiment) When 100 shots were printed using the gravure printing plate 12 according to embodiment 1 and the presence or absence of paste adhesion to the area outside the printing range was confirmed, no paste adhesion to the area outside the printing range was confirmed. On the other hand, as a comparative example, when 100 shots were printed using a gravure printing plate having sharp corners at the four outer corners of the printing pattern 121, adhesion of paste to the area outside the printing range was confirmed in the 13th shot.

[0041] (Manufacturing method for laminated electronic components) 6 is a diagram showing a manufacturing flow for manufacturing a laminated electronic component using the gravure printing plate according to embodiment 1. The manufacturing method for the laminated electronic component according to embodiment 1 will be described with reference to FIG.

[0042] As shown in Fig. 6, when manufacturing a multilayer ceramic capacitor as a multilayer 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 from a dielectric paste obtained by kneading ceramic powder, such as barium titanate, a binder, a dispersant, a plasticizer, and the like. The conductive paste 14 is obtained by kneading conductive powder, a solvent, a binder, ceramic powder, and the like. The green sheet 30 and the conductive paste 14 may be publicly known ones.

[0043] 1, the conductive paste 14 for the internal electrodes is transferred in a predetermined pattern onto the green sheet 30 using a gravure printing plate 12. This results in a dielectric sheet 25 having an electrode pattern 31 formed thereon. The gravure printing plate 12 may be used when transferring the dielectric paste.

[0044] Subsequently, in step (S3), a plurality of dielectric sheets are laminated to produce a laminated sheet. Specifically, a predetermined number of dielectric sheets for outer layers on which no electrode pattern is printed are laminated, dielectric sheets 25 on which electrode pattern 31 is printed are laminated in sequence thereon, and a predetermined number of the dielectric sheets for outer layers are laminated thereon.

[0045] Subsequently, in step (S4), a laminated block is produced by pressing the laminated sheets in the lamination direction using a pressing device such as a hydrostatic press.

[0046] Next, in step (S5), a laminated chip is produced. Specifically, the laminated block is cut into a predetermined size using a cutting blade to cut out the laminated chip. At this time, the corners and ridges of the laminated chip may be rounded by barrel polishing or the like.

[0047] Next, in step (S6), the laminated chip is sintered at a sintering temperature of, for example, about 900° C. to 1300° C., depending on the materials of the dielectric material and the electrode pattern.

[0048] Next, in step (S7), external electrodes are formed. For example, a conductive paste for external electrodes is applied to both end surfaces of the laminated chip and baked to form baked layers on the end surfaces. At this time, the baking temperature is, for example, 700°C to 900°C. Next, a plating layer is provided on the surface of the baked layer as necessary. Through the above steps, a laminated electronic component can be manufactured.

[0049] (Embodiment 2) 7 is a diagram showing a cross section of a recessed portion of a gravure printing plate according to embodiment 2. Gravure printing plate 12A according to embodiment 2 will be described with reference to FIG.

[0050] 7, the gravure printing plate 12A according to the second embodiment differs from the gravure printing plate 12 according to the first embodiment in the shape of the recesses 42 (more specifically, the bottom surface portions 421). The other configurations are substantially the same.

[0051] In the second embodiment, in addition to wall surface portions 43, bottom surface portion 421 is also formed of a curved surface. Bottom surface portion 421 has a shape that curves toward the center of recess 42 as it extends in the depth direction. The radius of curvature of bottom surface portion 421 may be larger than the radius of curvature of wall surface portions 43. The radius of curvature can be confirmed by peeling off a portion of peripheral surface 12p of gravure printing plate 12, cutting the peeled off portion, and observing it under an optical microscope.

[0052] Even when configured in this manner, the gravure printing plate 12A according to embodiment 2 achieves substantially the same effects as those of embodiment 1. Because the bottom surface portion 421 is configured as a curved surface, the conductive paste 14 becomes more likely to separate from the gravure printing plate 12A during transfer.

[0053] In addition, by making the radius of curvature of bottom surface portion 421 larger than the radius of curvature of wall surface portion 43, the peeling force can be applied more smoothly to conductive paste 14. As a result, conductive paste 14 can be transferred to green sheet 30 more smoothly.

[0054] (Embodiment 3) 8 is an enlarged view of a printing pattern of a gravure printing plate according to embodiment 3. The gravure printing plate according to embodiment 3 will be described with reference to FIG.

[0055] 8, the gravure printing plate according to the third embodiment differs from the gravure printing plate 12 according to the first embodiment in terms of the printing pattern 121. The other configurations are almost the same.

[0056] In the third embodiment, a plurality of cutouts 47, 48 are provided in the bank portion 41. The cutouts 47, 48 are provided so that adjacent recesses 42 communicate with each other. The depth of the recesses 42 is greater than the depth of the cutouts 47, 48. Corners 46c, 47c of the bank portion facing the cutouts 47, 48 are rounded.

[0057] A plurality of cutouts 47 are provided in each vertical bank portion 45. Note that each vertical bank portion 45 may be provided with a single cutout portion 47 instead of a plurality of cutouts 47.

[0058] The cutout portion 47 is provided in a portion of the vertical bank portion 45 located between adjacent recesses 42 in a direction parallel to the axial direction CL. The cutout portions 47 provided in the portions located between the plurality of recesses 42 aligned in the axial direction CL may be arranged side by side in the axial direction CL or may be arranged offset in the circumferential direction.

[0059] A plurality of cutouts 48 are provided in each of the lateral banks 46. Note that each of the lateral banks 46 may be provided with a single cutout 47 instead of a plurality of cutouts 47.

[0060] The cutout portion 48 is provided in a portion of the lateral bank portion 46 that is located between adjacent recesses 42 in a direction parallel to the axial direction CL. The cutout portions 48 provided in the portions that are located between each of the multiple recesses 42 that are lined up in the circumferential direction may be arranged side by side in the circumferential direction, or may be arranged offset in a direction parallel to the axial direction CL.

[0061] Even when configured as described above, the gravure printing plate according to embodiment 3 achieves substantially the same effects as embodiment 1. By providing a plurality of cutout portions 47, 48, the fluidity of conductive paste 14 can be improved.

[0062] Since the conductive paste 14 is transferred from the bank starting points, the number of transfer starting points can be increased by providing the cutouts 47 and 48. This allows the transfer to be performed evenly within the print pattern 121, improving printability.

[0063] Furthermore, by rounding the corners 46c, 47c of the bank portion facing the cutouts 47, 48, stringing can also be suppressed at the corners 46c, 47c when the transferred gravure printing plate 12 is separated from the sheet.

[0064] (Embodiment 4) 9 is an enlarged view of a printing pattern of a gravure printing plate according to embodiment 4. The gravure printing plate according to embodiment 4 will be described with reference to FIG.

[0065] 9, the gravure printing plate according to the fourth embodiment has a different printing pattern 121 compared to the gravure printing plate according to the third embodiment. The other configurations are almost the same. Note that in the fourth embodiment, the plurality of cutouts 47, 48 may be omitted.

[0066] In embodiment 4, the bank portion 41 includes an outer bank portion located on the peripheral side of the printing pattern 121 and an inner bank portion located more inward than the outer bank portion, and the thickness (width) of the outer bank portion is thinner than the thickness (width) of the inner bank portion.

[0067] Specifically, for example, the outer bank portion is a portion of the bank portion 41 that is located outside the imaginary line VL in the figure. The outer bank portion is composed of, for example, both end portions 451 of each vertical bank portion 45A in the circumferential direction and both end portions 461 of each horizontal bank portion 46A in the direction parallel to the axial direction CL.

[0068] The width (width W1) of both ends 451 of the vertical bank portion 45A is smaller than the width (width W3) of a portion 452 of the vertical bank portion 45A located between both ends 451. Similarly, the width (width W2) of both ends 461 of the horizontal bank portion 46A is smaller than the width (width W4) of a portion 462 of the horizontal bank portion 46A located between both ends 461.

[0069] Even when configured in this manner, the gravure printing plate according to embodiment 4 achieves substantially the same effects as the gravure printing plate according to embodiment 3. In addition, since the outer bank portion is thinner than the inner bank portion, transfer is promoted at the edges of the electrode pattern 31 during transfer, and smearing of the print can be suppressed.

[0070] (Other variations) Note that grooves with a width of 0.01 μm or more and 1 μm or less may be formed on the top 411 of the earthen part 41 and / or on the peripheral surface 12p of the gravure printing plate. The groove portion may extend in a direction parallel to the axial direction CL or may extend in the circumferential direction. By providing the groove portion, it becomes easier to scrape off the excess conductive paste 14 with the blade 13.

[0071] Also, the size of the recess 42 located inside the printing pattern 121 may be smaller than the size of the recess 42 located outside the printing pattern 121. By making the recess 42 located inside smaller, more earthen parts 41 can be formed. Since the conductive paste 14 is transferred starting from the earthen part 41, the transfer efficiency of the conductive paste 14 can be improved by arranging more earthen parts 41.

[0072] As described above, all aspects of the embodiments disclosed this time are illustrative and not restrictive. The scope of the present invention is indicated by the claims, and includes all modifications within the meaning and scope equivalent to the claims.

Explanation of Reference Numerals

[0073] 10 Gravure printing apparatus, 11 Backup roll, 12, 12A Gravure printing plate, 12p Peripheral surface, 13 Blade, 14 Conductive paste, 15 Paste tank, 25 Dielectric sheet, 30 Green sheet, 31 Electrode pattern, 41 Earthen part, 42 Recess, 42c Second corner part, 43 Wall surface part, 45, 45A Vertical earthen part, 46, 46A Horizontal earthen part, 47, 48 Notch, 47c, 48C Corner, 121 Printing pattern, 121c First corner part, 411 Top, 421 Bottom surface part, 431 First wall surface part, 432 Second wall surface part, 433 Third wall surface part, 434 Fourth wall surface part, 451, 461 Both ends, C1, C2 Central part, CL Axial direction, T1, T2 Connection position, TL1, TL2 Tangent line, VL Virtual line.

Claims

1. A cylindrical or columnar gravure printing plate for printing a paste on a ceramic green sheet, a peripheral surface provided with one or more printed patterns; Each of the one or more printing patterns has a plurality of recesses separated by bank portions arranged therein; The outer edge of the printing pattern is a rectangle having first corners whose four corners are rounded.

2. an outer edge of the recess that defines an opening surface of the recess has a rectangular shape having second corners whose four corners are rounded; The gravure printing plate according to claim 1 , wherein when the radius of curvature of the first corner portion is R1 and the radius of curvature of the second corner portion is R2, a relationship of R1>R2 is satisfied.

3. The bank portion is provided with a notch portion that connects adjacent recesses to each other, 2. The gravure printing plate according to claim 1, wherein corners of the bank portion facing the cutout portion are rounded.

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

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

6. the bank portion includes an outer bank portion located on the peripheral side of the print pattern and an inner bank portion located more inward than the outer bank portion, The gravure printing plate according to claim 1 , wherein the outer bank portion is thinner than the inner bank portion.

7. A step of transferring a dielectric paste or a conductive paste to form a sheet using the gravure printing plate according to any one of claims 1 to 6; forming a laminate including the sheet; and firing the laminate.

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