JP6214058B2 - Touch panel - Google Patents

Description

  The present invention relates to a projected capacitive touch panel capable of detecting multiple fingertips.

  In recent years, electronic devices such as mobile phones, smart devices (for example, tablet-type terminals and electronic book readers), car navigation systems, etc. have the advantage that they can be operated intuitively and have excellent durability as a form of interface. A display device having a touch panel function (display device with a touch panel: touch panel device) is mounted.

  The touch panel is a position input device that detects a touch by an indicator such as a finger or a stylus and specifies coordinates of the touch position. The detection method is a resistive film method comprising an analog resistive film method and a matrix resistive film method, a capacitive method comprising a surface capacitive method and a projected capacitive method, an optical comprising a infrared scanning method and a retroreflective method. There are broadly divided into an ultrasonic method consisting of a method, a surface acoustic wave method and a plate wave method, and various methods are put into practical use.

  Incidentally, in recent years, among the detection methods described above, in particular, the demand for a projected capacitive touch panel has increased. The projected capacitive touch panel detects a change in electrostatic capacitance of an electrode in the vicinity of a fingertip as position coordinates on the touch panel from two vertical and horizontal electrode rows.

  FIG. 4 is a partial sectional view showing an example of this type of projected capacitive touch panel. The projected capacitive touch panel 51 shown in FIG. 4 is provided in a first direction (for example, a lateral direction) on one surface (a back surface opposite to the surface on the operation surface side) of one substrate 52 having translucency. A plurality of rows of first electrodes (for example, X electrodes) made of a transparent conductive film extending and a plurality of rows of second electrodes made of a transparent conductive film extending in a second direction (for example, a vertical direction) intersecting the first electrodes. A configuration in which a sensor portion 54 having an electrode portion 53 in which electrodes (for example, Y electrodes) are stacked is formed, and the sensor portion 54 is fitted into an engagement recess 55a of the housing portion 55 via an adhesive material 56 such as a double-sided tape. Is produced as a basic structure. In addition, on the substrate 52, lead-out wiring portions 57 that are led out from the respective end portions of the electrode portions (first electrode, second electrode) 53 are formed via a decorative layer 58. Further, a protective layer 59 made of a transparent insulating film is formed so as to cover the entire electrode part 53 and the lead-out wiring part 57 of the sensor part 54. A display device 60 such as a liquid crystal display is bonded and fixed to a position of the substrate 52 facing the sensor unit 54 via an adhesive 61 such as a transparent adhesive tape. As such a projected capacitive touch panel, for example, the one disclosed in Patent Document 1 below is known.

JP 2011-90443 A

  By the way, when the projection capacitive touch panel 51 described above is attached to a mounted body 62 such as a back case or a printed circuit board, a mounting boss 63 is separately provided on the back side of the housing portion 55 of the touch panel 51. Provided. The mounting bosses 63 are provided by being adhesively fixed to a plurality of portions of the frame-like portion 55b on the back surface side of the housing portion 55 through an adhesive 64 such as an adhesive or a double-sided tape. Then, the touch panel 51 is attached to the mounted body 62 by engaging and fixing the mounting boss 63 to the receiving hole 62 a of the mounted body 62.

  For this reason, in the conventional touch panel 51, it is necessary to fix the mounting boss 63 to the housing portion 55, and there is a problem that it takes troublesome work and labor for fixing the mounting boss 63 to the housing portion 55. was there. In addition, the mounting boss 63 is bonded and fixed to the frame-like portion 55b on the back surface side of the housing portion 55 via an adhesive 64 such as an adhesive or a double-sided tape. There is a problem that the fixing position varies and the positional accuracy is poor, the adhesive strength decreases with use, and it cannot withstand long-term use.

  Further, the electrode part (first electrode, second electrode) 53 of the sensor part 54 of the touch panel 51 is connected to a control IC (not shown) from the end via the lead wiring part 57, but the lead wiring part 57 is external. As a countermeasure, a protective layer 59 made of a transparent insulating film has been conventionally formed so as to cover the entire surface of the lead-out wiring portion 57. It was.

  However, when a performance evaluation test was performed on the touch panel 51 on which the protective layer 59 of the transparent insulating film was formed under conditions of high temperature and high humidity (for example, 85 ° C., 85%), depending on the specifications of the protective layer, the time passed. It has been found that there is a risk that moisture from outside reaches the lead-out wiring part 57 through the protective layer 59 having moisture permeability and corrodes the lead-out wiring part 57. For this reason, the structure in which the lead wiring part 57 is simply covered with the protective layer 59 is required to further improve the corrosion resistance of the lead wiring part 57.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a touch panel that can improve the positional accuracy when attached to a mounted body and can withstand long-term use.

In order to achieve the above-described object, according to the first aspect of the present invention, a first electrode and a second electrode, each comprising a plurality of electrode rows, intersect each other, and the intersecting portions are insulated so as to be insulated. A projected electrostatic capacitance comprising a sensor part in which the first electrode and the second electrode are formed on the back surface of a substrate having optical properties, and a casing part that is insert-injection-molded while sandwiching the sensor part. In the touch panel of the method,
The housing portion is insert injection molded from a resin material so as to sandwich the outer edge portion of the substrate from above and below with the operation region of the sensor portion as a surface side,
The touch panel is characterized in that a mounting boss for mounting on a mounted body is formed integrally with the housing part at a position below the operation area on the substrate.

According to a second aspect of the present invention, in the touch panel according to the first aspect,
The casing is a touch panel, characterized in that it is formed so as to cover at least a region where a lead wiring portion of the first electrode and the second electrode is formed.

  According to the present invention, the mounting boss is molded integrally with the insert injection molded casing, so that there is no variation in the fixing position of the mounting boss with respect to the casing compared to the conventional structure. , Position accuracy is also improved and can withstand long-term use. In addition, since the mounting boss is located below the operation area on the substrate and is molded integrally with the casing, the mounting boss does not interfere with the operation of the touch panel without causing sink marks during insert injection molding. Can be formed integrally with the casing.

  Also, if the casing is insert injection molded so as to cover at least the area of the lead wiring part of each electrode, the entire lead wiring part is covered with resin, so that moisture from the outside is difficult to pass and corrosion of the lead wiring part is caused. A sufficient effect can be exhibited.

(A) It is the top view which looked at the sensor part of the touchscreen which concerns on this invention from the back surface side. (B) It is an AA line expanded sectional view of (a). (A) It is a top view of the touchscreen which concerns on this invention. (B) It is a BB partial expanded sectional view of (a), Comprising: It is a figure which shows an example when the mounting boss | hub is integrally molded in the housing | casing part. It is a partial expanded sectional view which shows an example of the structure which a sink occurs when the mounting boss | hub is integrally molded in a housing | casing part. It is a partial expanded sectional view which shows an example of the attachment structure of the conventional touch panel.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited by this embodiment, and other forms, examples, operational techniques, and the like that can be considered by those skilled in the art based on this form are all included in the scope of the present invention. To do.

  In the present specification, in the following description with reference to the accompanying drawings, when the words “up”, “down”, “left”, and “right” are used to indicate directions and positions, this is shown in FIG. Matches top, bottom, left, and right.

  The touch panel 1 according to the present embodiment is a projected capacitance that can detect multi-points of a fingertip by detecting a position coordinate on the touch panel from two vertical and horizontal electrode rows when a fingertip approaches the touch panel 1. The method is adopted.

  First, the configuration of the touch panel according to the present invention will be described with reference to FIGS. Note that the touch panel 1 of the present embodiment is illustrated and described as a rectangular shape in plan view, but the shape is not limited and may be, for example, a square, a circle, an ellipse, a polygon, or the like. May be.

  As shown to Fig.1 (a), the touch panel 1 of this embodiment is the 1st electrode 13 and 2nd electrode which are formed in the back surface (surface which opposes the surface used as an operation surface) of the board | substrate 11 which has translucency. The sensor part 2 which arrange | positions the electrode part 12 which consists of 14, and the housing | casing part 3 insert-insert-molded in the state which pinched | interposed the sensor part 2 in the up-down direction (front-and-back direction of the board | substrate 11) is comprised roughly. Is done.

  As shown in FIG. 1B, the sensor unit 2 has a rectangular plate-like substrate 11 as a base. The board | substrate 11 is formed with the insulating material which has translucency, for example, a glass type or a film type is used. As the glass substrate 11, for example, alkali-free glass, soda lime glass, aluminosilicate glass, or the like is used. Moreover, as the film-type substrate 11, for example, a resin film such as polyethylene terephthalate (PET) is used.

  A first electrode 13 and a second electrode 14 as electrode portions 12 are formed on the back surface (a surface opposite to the surface operated by the fingertip: hereinafter referred to as an operation facing surface) 11 a of the substrate 11. The first electrode 13 is, for example, a column in which a transparent conductive film such as ITO (Indium Tin Oxide) is patterned by a resist using a photolithography technique or the like and then subjected to an etching process, for example, a plurality of rows arranged in the vertical direction (X direction) in FIG. It is formed as an electrode.

  Similarly to the first electrode 13, the second electrode 14 is formed by etching a transparent conductive film such as ITO (Indium Tin Oxide) after patterning a resist using a photolithography technique or the like, for example, in the lateral direction (Y direction in FIG. 1). Are formed as a plurality of column electrodes.

  Further, the method for forming the electrode portion 12 will be described. First, the plurality of first electrodes 13 extending in the vertical direction (X direction) in FIG. In this state, a plurality of electrode films 14a arranged in the horizontal direction (Y direction) in FIG. Next, the insulating layer 16 is formed on the first electrode 13 at the intersection 15 between the first electrode 13 and the second electrode 14. The insulating layer 16 electrically insulates between the 1st electrode 13 and the 2nd electrode 14, for example, consists of insulating materials, such as an acrylic resin. Next, as shown in FIG. 1B, a plurality of electrode films 14a are connected by bridge wiring (jumper wiring) 17 across the first electrode 13 in the horizontal direction (Y direction) of FIG. Then, the second electrode 14 is formed. At this time, the bridge wiring 17 that connects the electrode films 14 a and 14 a constituting the second electrode 14 is wired so as to pass over the insulating layer 16. In this example, the inner rectangular portion in FIG. 2A where the electrode portion 12 is formed by the first electrode 13 and the second electrode 14 is used as the operation region E1 of the sensor portion 2.

  In the above-described method for forming the electrode portion 12, the bridge wiring 17 is used for the second electrode 14. However, the first electrode 13 and the second electrode 14 are reversed, and the first electrode 13 is connected to the bridge wiring 17. May be used. Moreover, since the 1st electrode 13 and the 2nd electrode 14 should just insulate the crossing part 15 at least, the insulating layer 16 is formed in the whole surface of one electrode (the 1st electrode 13 or the 2nd electrode 14), The other electrode (the second electrode 14 or the first electrode 13) may be formed on the insulating layer 16.

  As shown in FIG. 1A, each of the first electrode 13 and the second electrode 14 formed on the substrate 11 by the above-described forming method reaches the end of the substrate 11 by the lead-out wiring portion 18. It is drawn out and connected to a control IC (control circuit) (not shown).

  As shown in FIG. 2A, the lead-out wiring section 18 includes a first electrode 13 and a second electrode 14 in a lead-out wiring area E2 (shaded area in the drawing) outside the operation area E1. For example, a metal film such as MAM (Mo / Al / Mo), APC (Ag, Pd, Cu, etc.) is formed by sputtering, and a predetermined pattern is formed by etching. It is formed up to the end of the substrate 11.

  In addition, between the board | substrate 11 and the drawer | drawing-out wiring part 18, it is shielding so that the drawer | drawing-out wiring part 15 permeate | transmits from the surface 11b (surface operated with a fingertip: Hereafter, operation surface) side of the board | substrate 11 and cannot observe. The decorative layer 19 having a gap is formed.

  Thus, in order to maintain accuracy as a position sensor, the sensor unit 2 has an XY matrix on the substrate 11 in a state where the first electrode 13 and the second electrode 14 made of linear electrodes are electrically insulated. It is possible to independently detect which X direction electrode and which Y direction electrode, not where on which electrode, and calculate the position from the intersection.

  The housing | casing part 3 is comprised with thermoplastic synthetic resins, such as general purpose plastics and engineering plastics, for example. The housing unit 3 has the operation region E1 (region where the fingertip is operated) of the sensor unit 2 as a front surface side (operation surface 11b side of the substrate 11), and the operation facing surface 11a side of the outer edge portion of the substrate 11 is cut obliquely. Thus, the notch portion 11c is formed, the outer edge portions (four sides) of the substrate 11 are sandwiched from the top and bottom (front and back), and the surface 3a of the housing portion 3 and the operation surface 11b of the substrate 11 are flush with each other to be seamless. Thus, insert injection molding is performed using a resin material. Thereby, there is no fear that the board | substrate 11 will detach | leave from the housing | casing part 3 by strong impacts, such as dropping, like the fitting structure using the contact bonding layer like the conventional apparatus, and a reliable touch panel can be provided.

  In that case, the housing | casing part 3 is an area | region facing the extraction | drawer wiring area | region E2 of the extraction | drawer wiring part 18 of the electrode part 12 (1st electrode 13, 2nd electrode 14) formed in the operation opposing surface 11a side of the board | substrate 11. Insert injection molding to cover at least. Thereby, since the lead-out wiring part 18 is directly covered by the housing | casing part 3, it can ensure the reliability of a product, without the lead-out wiring part 18 corroding also under severe conditions like a performance evaluation test.

  At the time of insert injection molding of the casing 3, the plurality of mounting bosses 20 are molded integrally with the casing 3. The mounting bosses 20 are formed, for example, in a columnar shape or a prismatic shape, and are formed at the four corners on the back surface side of the housing portion 3, for example, located below the operation area E <b> 1 on the substrate 11 and integrally with the housing portion 3. . The mounting boss 20 is used when, for example, the housing 3 is fixedly attached to the mounted body 21 by being inserted into and engaged with a receiving hole 21a provided in the mounted body 21 such as a back case or a printed board. It is done.

  Note that the mounting of the mounting boss 20 to the mounted body 21 is not limited to the engagement by insertion into the receiving hole 21a. For example, the mounting boss 20 is fixed by screwing or the like. What is necessary is just a structure attached to. Further, the mounting boss 20 is not limited to a columnar or prismatic shape, and may be any shape or configuration that allows the housing 3 to be fixed to the mounted body 21.

  In addition, although not particularly illustrated, a configuration in which a metal is inserted into the mounting boss 20 may be employed according to the mounted body 21 to be mounted.

  In the touch panel 1 configured as described above, the operation facing surface 11a (surface on which the sensor unit 2 is formed) of the substrate 11 is, for example, an adhesive layer 22 such as a transparent adhesive tape, as shown in FIG. Is attached and fixed to a display device 23 (for example, various display devices such as a liquid crystal display and an EL display).

  Thereby, the display apparatus 23 can be functioned as a display apparatus with a touch panel (touch panel device) by mounting the touch panel 1 on the display apparatus 23 as one form of the input device.

  As described above, the touch panel 1 according to the present embodiment is inserted in the resin material so that the casing 3 sandwiches the outer edges (four sides) of the substrate 11 from above and below with the operation area E1 of the sensor unit 2 as the front side. Injection molded. At that time, the mounting boss 20 for mounting on the mounted body 21 is formed integrally with the housing unit 3 so as to be positioned below the operation region E1 on the substrate 11. Thereby, compared with the conventional structure, the position accuracy of the mounting boss 20 with respect to the housing 3 is not varied, the positional accuracy is improved, and it can withstand long-term use.

  Here, when the mounting boss 20 is formed integrally with the housing 3, when the mounting boss 20 is formed outside the substrate 11 as shown in FIG. 3, the housing 3 is insert-molded. As a defect at the time of contraction, sink marks 24 are generated on the surface 3a of the casing 3 facing the mounting boss 20.

  On the other hand, in the touch panel 1 of the present embodiment, the molding position of the mounting boss 20 is below the operation area E1 on the substrate 11, and the substrate 11 is positioned above the mounting boss 20, so FIG. Sink 24 does not occur on the surface of the casing 3 as shown in FIG. Accordingly, the mounting boss 20 can be integrally formed with the housing 3 at a position that does not interfere with the operation of the touch panel 1 without causing sink marks 24 during insert injection molding.

  The casing 3 is insert injection molded so as to cover at least the region of the lead wiring portion 18 of each electrode of the first electrode 13 and the second electrode 14, and the entire lead wiring portion 18 is covered with resin. It is difficult for moisture from passing through, and a sufficient effect against corrosion of the lead-out wiring portion 18 can be exhibited.

DESCRIPTION OF SYMBOLS 1 ... Touch panel 2 ... Sensor part 3 ... Housing | casing part 3a ... Front surface 11 ... Board | substrate 11a ... Back surface (operation opposing surface)
11b ... surface (operation surface)
12 ... Electrode part
DESCRIPTION OF SYMBOLS 13 ... 1st electrode 14 ... 2nd electrode 14a ... Electrode film 15 ... Intersection 16 ... Insulating layer 17 ... Bridge wiring 18 ... Lead-out wiring part 19 ... Decorating layer 20 ... Mounting boss 21 ... Mounted object 21a ... Receiving hole 22 ... Adhesive layer 23 ... Display device 24 ... Sink E1 ... Operation area E2 ... Lead-out wiring area

Claims (2)

The first electrode and the second electrode are each formed on a back surface of a light-transmitting substrate so that the first electrode and the second electrode each composed of a plurality of electrode rows intersect each other, and the intersecting portions are insulated. In a projected capacitive touch panel comprising a sensor unit to be formed and a casing unit that is insert injection molded with the sensor unit being sandwiched,
The housing portion is insert injection molded from a resin material so as to sandwich the outer edge portion of the substrate from above and below with the operation region of the sensor portion as a surface side,
A touch panel, wherein a mounting boss for mounting on a mounted body is formed integrally with the housing portion at a position below the operation area on the substrate. The touch panel as set forth in claim 1, wherein the casing is formed so as to cover at least a region where the lead wiring portion of the first electrode and the second electrode is formed.

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