JP6692634B2 - Touch panel - Google Patents

Description

This invention relates to the touch panel where the conductive layer is formed by printing.

  In recent years, a printing method which is excellent in productivity and advantageous in terms of manufacturing cost has come to be used for forming an electrode pattern and a wiring pattern of various electronic devices such as a touch panel, a membrane switch, and a liquid crystal display. Of these, gravure offset printing is drawing attention as being suitable for forming fine patterns.

  In gravure offset printing, a gravure plate with recesses corresponding to the desired print pattern, a doctor blade that fills the recesses of the gravure plate with ink, and a blanket that rotates while contacting the gravure plate and receives ink are used. Be done. The ink transferred to the blanket is transferred to the print target, whereby a desired print pattern is printed on the print target.

  The blade of the doctor blade is pressed against the gravure plate with the required pressure and slides relative to the gravure plate, filling the recesses of the gravure plate with ink and scraping off excess ink on the surface of the gravure plate (squeezing). ) Is performed, for example, when the direction in which the recess of the print pattern formed on the gravure plate extends and the direction of the doctor blade (arrangement direction) match, the tip of the doctor blade falls into the recess. Can occur.

  When such a drop of the doctor blade occurs, uneven scraping or a part of the ink in the recess may be scraped off, which causes printing defects such as untransferred and defective shapes.

  Patent Document 1 describes a method (inking method) for avoiding a printing failure due to such a drop of the doctor blade. FIG. 8 and FIG. 9 show a state of performing inking described in Patent Document 1 and a device configuration used for performing inking.

  In FIG. 9, 11 is a base, 12 is a linear guide, 13 is a movable table that can travel (reciprocate) along the linear guide 12, and an angle can be changed (turned) on the movable table 13 in a horizontal plane. An alignment mechanism 14 is provided, and a plate fixing stage 15 is provided thereon. The plate fixing stage 15 can hold a plate-shaped plate (gravure plate) 16. When the plate 16 moves along with the travel of the linear guide 12 of the moving table 13, a blade (doctor blade) 17 extending in the horizontal direction orthogonal to the longitudinal direction of the linear guide 12 is brought into contact with the plate surface of the plate 16 from above. On the other hand, the blade 17 is relatively slid to perform inking.

  In Patent Document 1, in inking, first, the printing pattern 18 of the plate 16 is divided into a plurality of areas in the moving direction (X direction) of the moving table 13 during inking to set divided areas. In FIG. 8, divided regions 18a and 18b divided into two are set, and the main groove pattern direction (direction in which the angles of the plate grooves match most) 19a, with respect to the plate grooves provided in each divided region 18a and 18b, 19b is calculated for each of the divided areas 18a and 18b based on data such as the groove angle (direction in which the plate groove extends), the number of grooves, and the groove width.

  Then, when the blade 17 is slid to perform inking, when the blade 17 contacts the divided region 18a as shown in FIG. 8A, the main groove pattern direction 19a is at an angle larger than 0 degree with the longitudinal direction of the blade 17. The plate 16 is rotated together with the plate fixing stage 15 by the alignment mechanism 14 so as to be arranged. This allows the blade 17 to slide in an angular posture in which the longitudinal direction of the blade 17 deviates from the main groove pattern direction 19a, so that the tip of the blade 17 can be prevented from being caught in the plate groove.

  When the blade 17 comes into contact with the divided region 18b as the moving table 13 travels, the main groove pattern direction 19b is aligned with the longitudinal direction of the blade 17 at an angle larger than 0 degree, as described above. The mechanism 16 rotates the plate 16. Thereby, similarly to the above, the tip of the blade 17 can be prevented from being caught in the plate groove.

  As described above, in Patent Document 1, the printing pattern of the plate is divided into a plurality of divided regions in the relative movement direction with the blade at the time of inking, the main groove pattern direction is obtained for each divided region, and the inking is performed. By performing relative rotation between the plate and the blade so that the main groove pattern direction obtained for the divided area where the blade is in contact with the divided area of the print pattern is larger than 0 degree, It is possible to prevent the tip of the blade from falling into the plate groove and being caught, thereby preventing the occurrence of printing defects.

Japanese Patent No. 5347990

  By the way, the inking method as described in the above-mentioned Patent Document 1 requires a troublesome work of dividing the print pattern of the gravure plate and obtaining the main groove pattern direction for each divided area. The printing device of No. 1 cannot be used as it is, and it is necessary to prepare a new printing device having an alignment mechanism. In addition, there is a problem that it cannot be applied to roll type gravure offset printing.

  Furthermore, since the blade is not parallel to the main groove pattern direction of the gravure plate, the parallel relationship between the blade and the groove pattern is not completely eliminated, so that the blade does not drop or get caught. It is something that cannot be avoided.

The purpose of the present invention has been made in view of such circumstances, without the defective printing caused by grayed Labia printing satisfactorily to provide a touch panel that is to be able to form a conductive layer.

According to this invention, consists film of the cured conductive ink, a rectangular sensor area Princesa electrode rows arranged in configured to include a conductive layer and a lead-out wiring led out from the sensor electrode array panel The sensor electrode array is formed by a mesh of fine lines composed of line segments that obliquely intersect both the short side and the long side of the rectangle, and the short side of the lead wiring that extends in parallel with the short side. At least one of the parallel portion and the long-side parallel portion extending in parallel to the long side, the wiring not formed by the thin wire mesh is formed by the wavy line, and at least 1 included in the wiring formed by the wavy line It is assumed that each wavy line is provided with a W-shaped notch at the apex of the folded portion protruding in at least one of two directions in a direction orthogonal to the extension direction of the wavy line. .

By the this invention lever, without print failure occurs, it is Rukoto give a touch panel conductive layer is made form a good good.

FIG. 3 is a schematic diagram for explaining the outline of a roll type gravure offset printing apparatus. The figure for explaining the outline of composition of the touch panel which is the subject of this invention. 2A is a partially enlarged view showing details of a first sensor electrode array of the touch panel shown in FIG. 2, and B is a partially enlarged view showing details of a second sensor electrode array of the touch panel shown in FIG. The elements on larger scale which show the 1st sensor electrode row | line in one Example of the touch panel by this invention, and the drawing-out wiring pulled out from the 1st sensor electrode row | line. The elements on larger scale which show the extraction wiring pulled out from the 1st sensor electrode row | line in one Example of the touch panel by this invention. A is a diagram showing a first example of a wavy line shape of a wiring pattern, and B is a diagram for explaining tailing and bleeding of ink. A is a diagram showing a second example of the wavy line shape of the wiring pattern, B is a diagram showing a third example of the wavy line shape of the wiring pattern, and C is a diagram showing a fourth example of the wavy line shape of the wiring pattern. A is a plan view showing a state where the blade is in contact with the first divided area of the print pattern in the conventional inking method in the gravure offset printing, and B is a second divided area of the print pattern after the state of A. The top view which shows the state which is contacting with. The side view which shows the apparatus structure used for implementation of the conventional inking method in gravure offset printing.

  First, the outline of roll-type gravure offset printing applied to the present invention will be described.

  FIG. 1 shows the configuration of a gravure offset printing apparatus. Ink 24 is supplied by a dispenser 23 to a cylindrical gravure plate 22 attached to a gravure cylinder 21. The ink 24 is filled by the doctor blade 25 into the concave portion 22a that defines the printing pattern formed on the gravure plate 22, and the excess ink 24 is scraped off by the doctor blade 25 so that the ink 24 is uniformly contained in the concave portion 22a. Be blunted. The ink 24 filled in the concave portion 22a of the gravure plate 22 is attached to the blanket cylinder 26, and the blanket 27 that rotates while being pressed against the gravure plate 22 is pulled out and transferred onto the blanket 27. The ink 24 transferred onto the blanket 27 Is retransferred (transferred) to the flown substrate (printing substrate) 28 and printed.

  In the gravure offset printing, the present invention can eliminate printing defects caused by the doctor blade 25 dropping into the concave portion 22a of the gravure plate 22 by using the conventional gravure offset printing apparatus as it is. Yes, a specific example will be described below.

  FIG. 2 shows an outline of the configuration of a capacitive touch panel. In FIG. 2, 30 indicates a transparent substrate. The capacitive touch panel has a structure in which, for example, a first conductor layer, an insulating layer, a second conductor layer, and a protective film are sequentially laminated on a transparent substrate 30.

  Although not illustrated in detail in FIG. 2, the sensor electrode array is composed of a plurality of first sensor electrode arrays and a plurality of second sensor electrode arrays, and the plurality of first sensor electrode arrays are the first conductors. The plurality of second sensor electrode arrays are formed by layers, and are formed by a second conductor layer that is insulated from the first conductor layer by an insulating layer. In FIG. 2, a portion surrounded by a rectangular frame shows the sensor region 40 in which the sensor electrode array is located.

  FIG. 3A shows details of the first sensor electrode row 51 formed by the first conductor layer, and FIG. 3B shows the second sensor electrode row 61 formed by the second conductor layer. It shows the details.

  The first sensor electrode array 51 includes a plurality of island-shaped electrodes 52 arranged in the X direction parallel to the long sides 41 of the rectangular sensor region 40, and a connecting portion 53 that connects adjacent island-shaped electrodes 52. .. A plurality of first sensor electrode rows 51 are arranged in parallel in the Y direction parallel to the short side 42 of the rectangular sensor region 40. The second sensor electrode array 61 includes a plurality of island-shaped electrodes 62 arranged in the Y direction, and a connecting portion 63 that connects adjacent island-shaped electrodes 62. A plurality of second sensor electrode arrays 61 are arranged in parallel in the X direction. The first sensor electrode row 51 and the second sensor electrode row 61 intersect with each other while being insulated from each other, and the connecting portions 53 and 63 are located at positions overlapping with each other. As shown in FIGS. 3A and 3B, the first sensor electrode array 51 and the second sensor electrode array 61 are composed of line segments that obliquely intersect both the long sides 41 and the short sides 42 of the sensor region 40, and The island-shaped electrodes 52 and 62 are formed of a fine mesh that forms a large number of cell-shaped voids, and the outer shape of the island-shaped electrodes 52 and 62 is a rhombus shape.

  The lead wires 71 and 72 and the terminal portion 73 shown in FIG. 2 are formed by the first conductor layer, and the ground wire 74 is formed on both the first and second conductor layers. The lead wires 71 are led out from both ends in the X direction of each first sensor electrode row 51, and the lead wires 72 are led out from one end in the Y direction of each second sensor electrode row 61. Note that, in FIG. 2, the lead wires 71 and 72 arranged in a plurality and led out from the sensor region 40 are shown only at the both ends of the array, and the ones other than those at the both ends are not shown.

  The terminal portion 73 is arranged and formed in the central portion of one long side of the transparent substrate 30 having a rectangular shape, and the lead wires 71 and 72 extend to the terminal portion 73 and are connected to the terminal portion 73. The ground wiring 74 is formed on the peripheral portion of the transparent substrate 30 so as to surround the sensor region 40 and the lead wirings 71 and 72. The ground wiring 74 is also connected to the terminal portion 73.

  Although not shown in detail, the thick terminal portion 73 and the ground wiring 74 are diagonally intersected with both the long side 41 and the short side 42 of the sensor region 40, like the first and second sensor electrode rows 51 and 61. It is composed of line segments, and is formed of a fine wire mesh including a large number of cellular voids in the extension direction and the width direction. The thin lead wires 71, 72 are line-shaped (line-shaped) wires.

  When the first and second conductor layers having the above structure are formed by printing with the gravure offset printing apparatus shown in FIG. 1 using a conductive ink containing conductive particles such as silver, a pattern of the conductor layers is defined. The squeezing direction of the doctor blade with respect to the gravure plate having the concave portion is parallel to the long side 41 of the sensor region 40, that is, parallel to the long side of the transparent substrate 30, or parallel to the short side 42 of the sensor region 40, that is, It is either in the Y direction parallel to the short side of the transparent substrate 30.

  Since the first and second sensor electrode rows 51 and 61, the terminal portion 73 and the ground wiring 74 are formed by a mesh diagonally intersecting in both the X direction and the Y direction, these first and second sensor electrode rows The doctor blade does not fall into the concave portion of the gravure plate that defines the patterns of 51, 61, the terminal portion 73 and the ground wiring 74. On the other hand, since the lead wires 71 and 72 are composed of line segments extending in the X and Y directions, respectively, the doctor blade may fall into the concave portion of the gravure plate that defines the pattern of the lead wires 71 and 72. You can

  In order to eliminate such a drop of the doctor blade into the concave portion of the gravure plate, in the present invention, a long side parallel portion of the lead wires 71, 72 extending in the X direction parallel to the long side 41 of the sensor region 40. And one of the short side parallel portions extending in the Y direction parallel to the short side 42 of the sensor region 40 is constituted by a wavy line.

  As shown in FIG. 2, the lead wiring 71 extends from the connection portion with the first sensor electrode row 51 toward the connection portion with the terminal portion 73 in a long side parallel portion 71a, a short side parallel portion 71b, and a long side parallel portion. It has a portion 71c and a short side parallel portion 71d, and the lead wiring 72 extends from the connection portion with the second sensor electrode row 61 toward the connection portion with the terminal portion 73, and is parallel to the short side 72a and parallel to the long side. It has a portion 72b and a short side parallel portion 72c. In this example, a long short side parallel portion 71b of the lead wiring 71 is formed by a wavy line with respect to these portions.

  FIG. 4 shows in detail the short side parallel portions 71b of the lead wires 71 arranged in a large number, which are constituted by wavy lines. FIG. 5 shows the short side parallel portions 71b of the lead wires 71 to the long side parallel. The transition to the portion 71c is shown in more detail. In this example, the short long-side parallel portion 71a of the lead-out wiring 71, which is a connecting portion with the first sensor electrode array 51, is a mesh diagonally intersecting with both the X direction and the Y direction as shown in FIG. Is formed by.

  As described above, in this example, the long short side parallel portion 71b of the lead-out wiring 71 is formed by a wavy line. The long side parallel portion 72b of the lead wiring 72 is formed by a normal straight line. Although other short side parallel portions 71d of the lead wiring 71 and short short side parallel portions 72a and 72c of the lead wiring 72 are not shown in detail, in this example, like the long side parallel portion 71a of the lead wiring 71, It is made of mesh.

  In this way, the short-side parallel portion 71b of the lead-out wiring 71 is formed by the wavy line, and the first conductor layer is printed by gravure offset printing. At the time of printing, the conductive ink is extended to the gravure plate having the concave portion defining the pattern of the first conductor layer so as to be parallel to the extension direction of the wavy line, that is, by the doctor blade installed in the Y direction. It is filled by squeezing in a direction (X direction) orthogonal to the direction. As a result, it is possible to prevent the doctor blade from falling into the concave portion of the gravure plate, and it is possible to eliminate the occurrence of printing defects due to the doctor blade falling and being caught.

  6A and 7A to 7C show various examples of wavy line shapes applied to the wiring pattern.

  In the wiring pattern 100 having the wavy line shown in FIG. 6A, the wavy line has a triangular wave. FIG. 6B shows a shape defect that may occur in the printed wiring pattern 100 when the gravure offset printing is performed with the wavy line as a triangular wave. In FIG. 6B, the arrow S indicates the squeezing direction of the doctor blade. The tailing of the ink marked with a may occur from the folded portion (corner) of the triangular wave located on the front side with respect to the squeezing direction, and the bleeding of the ink marked with b may occur in the folded portion of the triangular wave. ..

  If such tailing or bleeding of the ink becomes large, it may come into contact with an adjacent wiring pattern and cause a circuit failure, which becomes a factor to prevent the arrangement pitch of the wiring pattern from being narrowed.

  The wavy lines of the wiring patterns 110, 120, and 130 shown in FIGS. 7A to 7C are located on the front side with respect to the squeezing direction in order to reduce the risk of the tailing or bleeding contacting the adjacent wiring patterns as described above. A notch is formed at the top of the folded portion of the triangular wave.

  The wiring pattern 110 shown in FIG. 7A has a V-shaped cutout 111 formed in the folded portion, and the wiring pattern 120 shown in FIG. 7B has a cutout 121 formed by cutting the folded portion in a straight line. It was done. Further, the wiring pattern 130 shown in FIG. 7C has a W-shaped notch 131 formed at the folded portion. By providing the notch in this way, even if ink tailing or bleeding occurs, the size of them becomes small, so that the risk of contact with an adjacent wiring pattern can be reduced, and thus the arrangement of the wiring patterns can be reduced. The pitch can be narrowed. The wiring patterns 110, 120, and 130 shown in FIGS. 7A to 7C are notched with straight lines even at the folded-back portions protruding in the opposite direction from the folded-back portions where the notches 111, 121, and 131 are formed. 112, 122 and 132 are formed respectively.

  The wavy line shape of the wiring pattern is not limited to the triangular wave as described above, and may be a wavy line shape composed of a curved line such as a sine wave, and if the doctor blade is sufficiently short so as not to fall, the wavy line extension direction It may have a wavy line shape such as a trapezoidal wave including a line segment element parallel to the.

  The wavy line shape shown in FIG. 7A is applied to the short side parallel portion 71b of the lead wiring 71 of the touch panel shown in detail in FIGS.

  In the touch panel shown in FIG. 2, the long short side parallel portion 71b of the lead-out wiring 71 parallel to the short side 42 of the sensor region 40 is formed by a wavy line. The long long-side parallel portion 71c of the parallel lead-out wiring 71 and the long long-side parallel portion 72b of the lead-out wiring 72 may be formed by wavy lines, and either the short-side parallel portion or the long-side parallel portion is formed by wavy lines. It Then, in the gravure offset printing, the conductive ink is squeezed in a direction orthogonal to the extending direction of the wavy line by a doctor blade installed so as to be parallel to the extending direction of the wavy line. In addition, when a notch is provided at the apex of the folded portion projecting in one specific direction out of two directions in the direction orthogonal to the extending direction of the wavy line, as shown in FIGS. Squeeze the conductive ink in the direction with a doctor blade.

  As still another form, the long short side parallel portion 71b of the lead wiring 71 parallel to the short side 42 of the sensor region 40, the long long side parallel portion 71c of the lead wiring 71 parallel to the long side 41, and the lead wiring 72 are provided. All the long long-side parallel portions 72b may be formed by wavy lines so that the squeegee can be squeezed well in both the directions parallel to the short sides 42 and the long sides 41 of the sensor region 40.

  In addition, as still another embodiment, the notches of the vertices of the folded portion of the wavy line shown in FIGS. 7A to 7C are formed at the vertices on both sides of the wavy line in any of two directions opposite to each other. You may be able to squeeze well. This is useful, for example, when the ink is thoroughly filled by performing squeezing twice in a single direction.

  Although the touch panel has been described above as an example, in a printed wiring having a wiring pattern made of a cured conductive ink film on a base material, the wiring pattern extending in one or more specific directions on the surface of the base material. All of the wiring patterns are formed by wavy lines, or at least all the wiring patterns that are extended in one or more specific directions and are not formed by the fine mesh are formed by wavy lines. When a wiring pattern is printed, conductive ink is squeezed in a direction orthogonal to the direction of the doctor blade by a doctor blade installed so as to be parallel to a specific direction of one or more of the wiring patterns. This will prevent the doctor blade from falling into the concave part of the gravure plate, and Drop in coater blades, it is possible to eliminate the occurrence of printing failure attributed to snag. Also, for example, when the device for printing the wiring has a square outer shape, two orthogonal directions parallel to the respective sides are set as the specific directions, and when notches are provided at the folded portions of the wavy lines, they are provided at the apexes on both sides. Every other side, you should be able to perform good squeezing even if you install it on the printing machine in any direction along each side, or select one from multiple specific directions depending on the situation and use it. Is also possible. The present invention is directed to an electronic device such as a printed wiring and a touch panel including the printed wiring, which can eliminate the occurrence of the print defect in this way.

  The printing used is not limited to roll-type gravure offset printing, and may be flat-plate gravure offset printing or gravure printing.

11 Base 12 Linear Guide 13 Moving Table 14 Alignment Mechanism 15 Plate Fixed Stage 16 Plate 17 Blade 18 Printing Patterns 18a, 18b Divided Areas 19a, 19b Main Groove Pattern Direction 21 Gravure Cylinder 22 Gravure Plate 22a Recess 23 Dispenser 24 Ink 25 Doctor Blade 26 Blanket cylinder 27 Blanket 28 Base material 30 Transparent substrate 40 Sensor area 41 Long side 42 Short side 51 First sensor electrode row 52 Island electrode 53 Connecting portion 61 Second sensor electrode row 62 Island electrode 63 Connecting portion 71 Lead-out wiring 71a, 71c Long-side parallel part 71b, 71d Short-side parallel part 72 Lead-out wiring 72a, 72c Short-side parallel part 72b Long-side parallel part 73 Terminal 74 Ground wiring 100, 110, 120, 130 Wiring pattern 111, 1 2,121,122,131,132 notch

Claims (1)

A touch panel composed of a cured conductive ink film, comprising a sensor electrode array arranged in a rectangular sensor region, and a conductor layer having lead wires drawn from the sensor electrode array,
The sensor electrode array is formed by a thin wire mesh composed of line segments obliquely intersecting both the short side and the long side of the rectangle,
Of the lead-out wiring, at least one of a short-side parallel portion extending parallel to the short side and a long-side parallel portion extending parallel to the long side is not formed of a thin wire mesh. The wiring is composed of wavy lines,
The at least one wavy line included in the wiring formed by the wavy line has a W-shape at the apex of the folded portion protruding in at least one of two directions in a direction orthogonal to the extension direction of the wavy line. A touch panel having a cutout.

Images