Gravure printing plate and method for manufacturing laminated electronic component

Abstract

To provide a gravure printing plate capable of suppressing wear, and a method for manufacturing an electronic component using the printing plate.SOLUTION: A gravure printing plate has a cylindrical or columnar shape and includes: a base member 50 provided with a printing pattern on its outer peripheral surface, the printing pattern comprising a plurality of recesses 42 separated by a plurality of bank portions 41; a Cr plating layer 51 formed on a surface of the base member 50 so as to cover the plurality of recesses 42 and the plurality of bank portions 41; and a DLC layer 52 formed on the Cr plating layer 51.SELECTED DRAWING: Figure 4

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, and the paste is filled into recesses in the gravure printing plate and transferred to the paste 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] When filling the recesses of the gravure printing plate with paste, excess paste adheres to the outer peripheral surface of the gravure printing plate. For this reason, a blade is abutted against the outer peripheral surface to scrape off the excess paste, but this can cause the gravure printing plate to wear down with use.

[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 suppressing wear, and a method for manufacturing electronic components using the printing plate. [Means for solving the problem]

[0006] A gravure printing plate according to the present disclosure comprises a substrate having a cylindrical or columnar shape and having a printing pattern on its outer peripheral surface composed of a plurality of recesses separated by a plurality of bank portions, a Cr plating layer provided on the surface of the substrate so as to cover the plurality of recesses and the plurality of bank portions, and a DLC layer provided on the Cr plating layer.

[0007] In the gravure printing plate according to the present disclosure, the surface of the substrate may have a first portion constituting the top of the bank, a second portion constituting the bottom of the recess, and a third portion constituting the side of the bank and connecting the first portion and the second portion. The thickness of the portion of the DLC layer covering the top of the third portion may be greater than the thickness of the portion of the DLC layer covering the first portion and the thickness of the portion of the DLC layer covering the second portion.

[0008] In the gravure printing plate according to the present disclosure, the third portion may include a curved surface portion that curves from the first portion toward the second portion in a depth direction of the recess.

[0009] In the gravure printing plate according to the present disclosure, the portion of the Cr plating layer that covers the first portion may have a thickness of 3 μm or more.

[0010] In the gravure printing plate according to the present disclosure, the portion of the DLC layer that covers the first portion may include a flat portion.

[0011] A method for producing a laminated electronic component according to the present disclosure includes the steps of transferring a dielectric paste or a conductive paste using the gravure printing plate described above to form a sheet, forming a laminate including the sheet, and firing the laminate. Effect of the Invention

[0012] According to the present disclosure, it is possible to provide a gravure printing plate capable of suppressing wear, and a method for manufacturing electronic components using the printing plate. [Brief description of the drawings]

[0013] [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 part of the 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] 2 is a diagram for explaining a flat portion in the gravure printing plate according to the first embodiment. [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 cross-sectional view showing the shape of recesses in a gravure printing plate according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, a first embodiment of the present disclosure will be described in detail with reference to the drawings. In the first embodiment 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.

[0015] (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.

[0016] The gravure printing apparatus 10 includes a backup roll 11 , a gravure printing plate 12 , a blade 13 , and a paste tank 15 .

[0017] The backup roll 11 and the gravure printing plate 12 are arranged to face each other so that a nip portion is formed. The green sheet 30 passes through the nip portion with the dielectric sheet 25 sandwiched therebetween.

[0018] The backup roll 11 has a cylindrical shape or a tubular shape. The backup roll 11 is provided rotatably in the direction of arrow AR1 in FIG. 1.

[0019] As shown in FIG. 2, the gravure printing plate 12 has a cylindrical shape or a tubular shape. The diameter of the gravure printing plate 12 is, for example, about 10 mm to 400 mm. The width parallel to the axial direction of the gravure printing plate 12 is, for example, about 150 mm to 300 mm. A plurality of printing patterns 121 are provided on the gravure printing plate 12.

[0020] As shown in FIG. 1 again, the gravure printing plate 12 is provided rotatably in the direction of AR2 in FIG. 1.

[0021] The conductive paste 14 is stored in the paste tank 15. A part of the gravure printing plate 12 is immersed in the conductive paste 14, and when gravure printing is performed, by rotating in the direction of AR2 in the figure, the conductive paste 14 is filled into a plurality of recesses 42 (see FIG. 3) described later.

[0022] The blade 13 is disposed on the downstream side 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.

[0023] Subsequently, when the gravure printing plate 12 holding an appropriate amount of the conductive paste 14 passes through the nip portion, the conductive paste 14 filled in the recess 42 is transferred to the green sheet 30, and an electrode pattern 31 corresponding to the printing pattern 121 is printed on the green sheet 30.

[0024] Fig. 3 is an enlarged view of a portion 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 of the gravure printing plate parallel to the depth direction of a recess 42 (described below) in the central portion of a vertical bank portion (described below) in the circumferential direction and the axial direction. The detailed structure of gravure printing plate 12 will be described with reference to Figs. 3 and 4.

[0025] 3, the print pattern 121 is composed of a plurality of recesses 42 separated by a plurality of bank portions 41. The plurality of recesses 42 are provided on the outer surface of a substrate 50 described below. The plurality of bank portions 41 are provided, for example, in a lattice pattern, and include vertical bank portions 45 extending in the circumferential direction and horizontal bank portions 46 extending in a direction parallel to the axial direction.

[0026] 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 printed pattern 121 has a substantially rectangular shape, but is not limited thereto, and an appropriate shape can be adopted depending on the shape of the electrode pattern 31.

[0027] As shown in a cross section of the gravure printing plate 12 parallel to the axial direction of the gravure printing plate 12 in FIG. 4, the gravure printing plate 12 includes a substrate 50, a Cr plating layer 51, and a DLC (Diamond-Like Carbon) layer 52.

[0028] For example, a metal roll can be used as the base material 50. The material of the metal roll can be an appropriate metal such as stainless steel. The metal roll may be columnar or cylindrical.

[0029] The surface of the base material 50 has a first portion 411, a second portion 412, and a third portion 413. The first portion 411 constitutes the top of the bank portion 41. The first portion 411 includes a flat portion. The second portion 412 constitutes the bottom of the recess 42. The third portion 413 connects the first portion 411 and the second portion 412. An upper portion 414 of the third portion 413 is approximately parallel to the depth direction of the recess 42. It is to be noted that the second portion does not necessarily have to include a flat portion.

[0030] The depth direction is a direction perpendicular to the opening surface OP of the recess 42. A lower portion 415 of the third portion 413 has a curved shape that curves toward the second portion 412 as it approaches the depth direction of the recess 42.

[0031] The depth of the recess 42 (specifically, the depth h from the opening surface OP of the recess 42 to the DLC layer 52) is about 5 μm to 40 μm. In the present embodiment 1, the opening surface OP has a rectangular shape, but is not limited to a rectangular shape and any appropriate shape can be adopted. The recess 42 is formed, for example, by etching the surface of the base material 50.

[0032] The Cr plating layer 51 is provided on the surface of the base material 50 so as to cover the multiple banks 41 and the multiple recesses 42. The Cr plating layer 51 is disposed with a uniform thickness. Here, the uniform thickness means a thickness variation within 0.1 μm to 0.3 μm.

[0033] The thickness of the Cr plating layer 51 is preferably 3 μm or more. If the thickness of the Cr plating layer 51 is 3 μm or more, the DLC layer 52 can be firmly fixed. The thickness of the Cr plating layer 51 is preferably 10 μm or less. If the thickness of the Cr plating layer 51 exceeds 10 μm, the portions covering the tops (first portions 411) of the banks 41 (more specifically, the vertical banks and the horizontal banks) will be rounded. In this case, printability will be reduced.

[0034] The DLC layer 52 is provided on the Cr plating layer 51. The DLC layer 52 is provided so as to cover the Cr plating layer 51.

[0035] The thickness of the DLC layer 52 is, for example, about 1 μm to 10 μm. If the thickness of the DLC layer 52 is less than 1 μm, the thickness of the DLC layer 52 varies greatly. If the thickness of the DLC layer 52 is more than 10 μm, the portion covering the top (first portion 411) becomes rounded. In this case, printability decreases.

[0036] The thickness of DLC layer 52 can be observed with a microscope such as an SEM by extracting the surface of gravure printing plate 12. DLC layer 52 can be formed by a method such as vapor deposition from the outside toward the peripheral surface of substrate 50 in a direction parallel to the radial direction of gravure printing plate 12.

[0037] A thickness T1 of a portion of the DLC layer 52 covering an upper portion 414 of the third portion 413 is greater than a thickness T2 of a portion of the DLC layer 52 covering the first portion 411 and a thickness T3 of a portion of the DLC layer 52 covering the second portion 412. In addition, the thickness of the upper portion 414 of the third portion 413 is thinner than a lower portion 415 of the third portion 413.

[0038] In this way, by thinning the DLC layer 52 in the portion covering the upper portion 414 of the third portion 413, which is not related to wear, the volume of the cell defined by the DLC layer 52 and the opening surface OP can be increased, thereby improving printability.

[0039] The DLC layer 52 may be a single layer or may be composed of multiple layers. When the DLC layer 52 is composed of multiple layers, Si may be blended into the interface between adjacent layers. The DLC layer 52 may also contain fluorine. Si and fluorine can be detected using EDX or the like.

[0040] The portion of DLC layer 52 that covers first portion 411 has a flat portion. In the portion corresponding to the vertical bank portion, the length of the flat portion in the direction parallel to the axial direction of gravure printing plate 12 is about 1 μm to 5 μm. Similarly, in the portion corresponding to the horizontal bank portion, the length of the flat portion in the direction parallel to the circumferential direction of gravure printing plate 12 is about 1 μm to 5 μm.

[0041] 5 is a diagram for explaining a flat portion in the gravure printing plate according to the first embodiment. In the above, the flat portion of the portion of the DLC layer 52 covering the first portion 411 means that, as shown in FIG. 5, the DLC layer 52 located at a depth of h1 from the topmost portion of the portion of the DLC layer 52 covering the first portion 411 includes a flat portion, with respect to a cell depth h from the opening surface OP of the recess 42 to the portion of the DLC layer 52 covering the third portion 413. In other words, the portion of the DLC layer 52 covering the first portion 411 may include an uneven portion, and this indicates that the flatness of the portion of the DLC layer 52 covering the first portion 411 is equal to or greater than a predetermined value.

[0042] As described above, in the gravure printing plate 10 according to the present embodiment, the DLC layer 52, which has low friction and a considerable degree of hardness, is provided so as to cover the Cr plating layer 51. This makes it possible to suppress wear of the gravure printing plate 10 even when the blade 13 is in sliding contact with the gravure printing plate 10.

[0043] (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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] (Embodiment 2) Fig. 7 is a cross-sectional view showing the shape of recesses in a gravure printing plate according to embodiment 2. Note that for convenience, the Cr plating layer and DLC layer are omitted in Fig. 7, but the gravure printing plate according to embodiment 2 includes a Cr plating layer 51 and a DLC layer 52, similar to embodiment 1. The gravure printing plate according to embodiment 2 will be described with reference to Fig. 7.

[0052] 7, the gravure printing plate according to the second embodiment differs from the gravure printing plate 12 according to the first embodiment mainly in the shape of the recesses 42A, but the other configurations are substantially the same.

[0053] Compared to embodiment 1, recess 42A has a longer length parallel to the axial direction of the gravure printing plate, and the length of the top (first portion 411) of bank portion 41 parallel to the axial direction is also longer. The length of the top parallel to the circumferential direction may be shorter than the length of the top parallel to the axial direction.

[0054] More specifically, for example, in a cross section of the gravure printing plate parallel to the axial direction and in the depth direction of recess 42A at the center of the vertical bank portion in the circumferential direction, lower portion 415 of third portion 413 has a substantially arc shape. The radius of curvature R of lower portion 415 and the length L of the top portion (first portion 411) of bank portion 41 parallel to the axial direction are substantially equal to each other.

[0055] Even when substrate 50 has banks 41 and recesses 42A as described above, gravure printing plate 10 according to the second embodiment achieves substantially the same effects as gravure printing plate 12 according to the first embodiment.

[0056] In the above-described embodiment 1-2, the gravure printing plate 12 is exemplified as being formed by etching the surface of the substrate 50, plating it with Cr, and then forming the DLC layer 52, but the present invention is not limited to this. After etching the substrate 50, the surface of the substrate 50 may be etched before plating it with Cr.

[0057] The embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, and includes all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0058] 10 gravure printing device, 11 backup roll, 12 gravure printing plate, 13 blade, 14 conductive paste, 15 paste tank, 25 dielectric sheet, 30 green sheet, 31 electrode pattern, 41 bank portion, 42, 42A recess, 45 vertical bank portion, 46 horizontal bank portion, 50 substrate, 51 plating layer, 52 DLC layer, 121 printing pattern, 411 first portion, 412 second portion, 413 third portion, 414 upper portion, 415 lower portion, OP opening surface, R radius of curvature.

Claims

1. A substrate having a cylindrical or columnar shape and a printing pattern formed on an outer circumferential surface thereof, the printing pattern being composed of a plurality of recesses separated by a plurality of banks; a Cr plating layer provided on a surface of the base material so as to cover the recesses and the banks; and a DLC layer provided on the Cr plating layer.

2. the surface of the base material has a first portion constituting a top of the bank portion, a second portion constituting a bottom of the recess portion, and a third portion constituting a side surface of the bank portion and connecting the first portion and the second portion; 2. The gravure printing plate of claim 1, wherein a thickness of the portion of the DLC layer covering the top of the third portion is greater than a thickness of the portion of the DLC layer covering the first portion and a thickness of the portion of the DLC layer covering the second portion.

3. The gravure printing plate according to claim 2 , wherein the third portion includes a curved surface portion that curves from the first portion toward the second portion in a depth direction of the recess.

4. The gravure printing plate according to claim 2 , wherein the thickness of the portion of the Cr plating layer covering the first portion is 3 μm or more.

5. The gravure printing plate of claim 4 , wherein the portion of the DLC layer covering the first portion includes a flat portion.

6. 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 5; forming a laminate including the sheet; and firing the laminate.

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