JP2017068819A - Touch panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a touch panel excellent in shock resistance and design on the side of an operation surface without arranging a decorative part.SOLUTION: On an operation surface 11b of a substrate 11, a cover member 19 is arranged on the inward side of a lead-out wiring area E2 so as to avoid the lead-out wiring area E2 of a lead-out wiring part 18 of a first electrode 13 and a second electrode 14. An outer edge of the substrate 11 is vertically held by a housing 3 which is manufactured by insert injection molding with a resin material, so that the surface of the cover member 19 and the surface 3a of the housing 3 are flush with each other up to a step difference formed with the substrate 11, which is generated due to arrangement of the cover member 19.SELECTED DRAWING: Figure 2

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. 5 is a partial cross-sectional view showing an example of this type of projected capacitive touch panel. The projected capacitive touch panel 51 shown in FIG. 5 has a translucent substrate 52 on one side (back side opposite to the operation side) and in a first direction (for example, lateral direction). 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, in the touch panel disclosed in Patent Document 1, the lead-out wiring portion 57 of the electrode portion 53 provided on the back surface of the substrate 52 is disposed in a region (outer periphery) other than the operation region, and the user touches from the operation surface side of the touch panel. A decorative layer 58 is provided so as not to touch the eyes.

  However, it is necessary to match the color of the decorative layer 58 in accordance with the color of the housing portion 55 so as not to hinder the design of the electronic device on which the touch panel is mounted. Is very difficult. In addition, since the number of touch panel processes increases because the decoration layer 58 is provided, there is a problem that the manufacturing cost increases.

  Furthermore, since the touch panel of Patent Document 1 is constructed such that the sensor unit 54 is fitted into the housing unit 55 and bonded and fixed via an adhesive 61, the sensor unit 54 is exposed to a strong impact such as dropping. There is a problem of leaving.

  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 thereof is to provide a touch panel that is excellent in impact resistance and excellent in design from the operation surface side without providing a decorative layer.

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,
A cover member is provided on the surface of the substrate so as to cover at least a part of the operation region while avoiding the lead-out wiring portion of the first electrode and the second electrode,
The casing portion is insert injection molded with a resin material so as to sandwich the outer edge portion of the substrate from above and below so as to be flush with the cover member without a step between the cover member and the substrate. It is a touch panel characterized by this.

  According to a second aspect of the present invention, there is provided the touch panel according to the first aspect, wherein the housing portion is formed so as to cover at least a surface of the lead-out wiring portion.

  According to a third aspect of the present invention, in the touch panel according to the first or second aspect, the cover member is a glass material.

  A fourth aspect according to the present invention is the touch panel according to the first or second aspect, wherein the cover member is a transparent resin material.

  According to a fifth aspect of the present invention, in the touch panel according to the fourth aspect, a protrusion is formed in a contact portion of the cover member with the casing.

  According to the present invention, the lead-out wiring portion can be shielded without the need to provide a decorative layer that shields the lead-out wiring portion from being visible from the outside, leading to a reduction in manufacturing costs. In addition, since the housing portion is insert-injection-molded with respect to the substrate, it is possible to provide a highly reliable touch panel that does not cause the substrate to be detached from the housing portion due to a strong impact such as dropping. Furthermore, if the shape of the cover member is designed to be an arbitrary shape such as a circle or a polygon, the design design can be arbitrarily changed by changing only the shape of the cover member while sharing the sensor portion.

  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) is the top view which looked at the sensor part of the touch panel concerning the present invention from the back side, and (b) is an AA line expanded sectional view of (a). (A) is a figure which shows an example of the plane of the touchscreen which concerns on this invention, (b) is the BB line | wire partial expanded sectional view of (a). It is a figure which shows the example of a mode when the protrusion for a removal | release prevention is provided in the cover member. (A), (b) is a figure which shows the example of formation of the notch part formed in a board | substrate. 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 projection type electrostatic that can detect multi-points of the fingertip by detecting the position coordinate on the touch panel 1 from two vertical and horizontal electrode rows, as the fingertip approaches the touch panel 1. The capacity method is adopted.

  First, the configuration of the touch panel 1 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 in any one of FIGS. 1 and 2, the touch panel 1 of the present embodiment includes a first electrode 13 and a first electrode 13 formed on the back surface (surface facing the operation surface) of the substrate 11 having translucency. A sensor unit 2 in which an electrode unit 12 including two electrodes 14 is arranged; and a housing unit 3 that is insert injection molded in a state in which the sensor unit 2 is sandwiched in the vertical direction (front and back direction of the substrate 11). Generally composed.

  As shown in FIG. 1A, 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.

  Thus, in order to maintain the accuracy as the position sensor, the sensor unit 2 has an XY matrix shape 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.

  Further, when the casing 3 is subjected to insert injection molding, the drawer is drawn on the surface side of the substrate 11 (the operation surface 11b side of the substrate 11) so that at least the operation surface 11b side of the substrate 11 facing the lead-out wiring portion 18 is covered. A cover member 19 is disposed with an adhesive layer 20 inward of the lead-out wiring area E2 so as to avoid the lead-out wiring area E2 of the wiring portion 18.

  The cover member 19 has a shape that avoids the lead-out wiring area E2 disposed on the operation facing surface 11a side when the casing 3 is insert injection molded. By disposing the cover member 19 on the operation surface 11b of the substrate 11, a step portion is formed between the cover 11 and the operation surface 11b of the substrate 11, and the resin material of the housing portion 3 is filled so that the step portion is filled at the time of insert injection molding. Can advance. Thereby, when it becomes the touch panel 1, since it can cover the lead-out wiring area | region E2 with the housing | casing part 3, when it becomes the touch panel 1, it is not necessary to provide the process of the board | substrate 11 itself, or a decoration layer, As with the conventional product, the lead-out wiring portion 18 can be shielded from the outside.

  When the cover member 19 is formed of a glass material, it is highly transparent and can be used for various purposes such as chemical resistance, weather resistance, wear resistance, etc. The point which can respond to environment is excellent.

  In addition, when the cover member 19 is formed of a transparent resin material (for example, polycarbonate, triacetyl cellulose, acrylic resin, etc.), the surface of the member has various coatings (one example) in that fragments caused by dropping damage are less likely to scatter than glass materials. AR coating (anti-reflection coating), AG coating (anti-glare coating), AFP coating (anti-fingerprint coating), etc.), and since the casing 3 is a resin material, the affinity between the resins is good Excellent in terms.

  Further, when a transparent resin material is used for the cover member 19, as shown in FIG. 3, a projection 19 a that functions as a fitting portion with the housing portion 3 is formed by resin molding at the contact portion with the housing portion 3. It can be easily formed in any shape. As described above, since the bonding area (contact area) with the housing portion 3 is increased by providing the protrusion 19a, it is possible to prevent the cover member 19 from falling out of the housing portion 3 when the touch panel 1 is dropped. it can. Note that the shape and number of the protrusions 19a shown in FIG. 3 are merely examples, and are not particularly limited as long as they have a shape, size, and number that are fitted to the housing 3 and have an effect of preventing removal.

  By the way, in order to prevent the touch panel 1 itself from becoming too thick when the cover member 19 is disposed on the substrate 11, the thickness of the substrate 11 and the thickness of the cover member 19 according to the thickness of the touch panel 1. Can be adjusted as appropriate. As an example, when the thickness of the conventional substrate 11 is 1.1 mm, for example, if the thickness of the substrate 11 is 0.5 mm and the thickness of the cover member 19 is 0.6 mm, the total thickness is 1.1 mm. Thus, the thickness is equivalent to the thickness of the substrate 11 that is generally used. Further, the cover member 19 is not limited to one sheet, and may be divided into a plurality of sheets (for example, if the target thickness is 0.6 mm, 0.2 mm is divided into three sheets) and may be overlapped.

  As described above, when the cover 3 is disposed on the operation surface 11b side of the substrate 11 so as to avoid at least the lead-out wiring area E2 and inward of the lead-out wiring area E2, the case 3 is subjected to insert injection molding. In addition, since the step portion generated between the cover member 19 and the substrate 11 is covered with the resin material, the decoration is provided without providing a decoration layer for shielding the lead-out wiring portion 18 as in the conventional device. An effect equivalent to the provision of the layer can be obtained. Further, since the resin material can advance to the stepped portion generated by the cover member 19, the surface of the cover member 19 and the housing portion 3 can be seamlessly made flush with each other.

  The cover member 19 may be disposed on the operation surface 11b of the substrate 11 after being processed into a shape such that at least the lead-out wiring region E2 is covered with the resin material of the housing 3 at the time of insert injection molding. For example, as shown to Fig.4 (a), what processed into the shape where the resin material of the housing | casing part 3 reaches in the operation area | region E1 can also be arrange | positioned.

  Since the resin material used for the housing part 3 has a high dielectric constant, the position of the fingertip can be detected by the electrode part 12 even from the surface 3a of the housing part 3 extending over the operation region E1. . Therefore, when the cover member 19 is arranged as shown in FIG. 4A, a part of the operation region E1 is covered with the resin material of the housing portion 3, and the portion covering the operation region E1 is, for example, shown in FIG. ) Are printed, and the electrode unit 12 is set so that each button functions, so that the operation function can be easily performed without forming a separate push button on the housing unit 3. Can be added.

  Moreover, since the shape of the cover member 19 can be designed in an arbitrary shape such as a circle or a polygon, the design design can be arbitrarily set by changing only the shape of the cover member 19 while keeping the sensor unit 2 in common. Can be changed.

  The housing | casing part 3 is comprised with thermoplastic synthetic resins, such as general purpose plastics and engineering plastics, for example. The casing 3 has a stepped portion caused by the cover member 19 disposed on the operation surface 11b of the substrate 11 with the operation surface 11b side serving as the operation region E1 (region where the fingertip is operated) of the sensor unit 2 as a surface. The outer edge of the substrate 11 is sandwiched from above and below (front and back) so as to cover, and insert injection molding is performed with a resin material so that the surface 3a of the housing 3 and the surface of the cover member 19 are flush with each other.

  Further, the housing 3 is inserted so as to cover at least the lead-out wiring region E2 of the lead-out wiring part 18 of the electrode part 12 (first electrode 13 and second electrode 14) formed on the operation facing surface 11a side of the substrate 11. Injection molding. Thereby, since the lead-out wiring part 18 is directly covered with the housing | casing part 3, the reliability of a product can be ensured also under severe conditions like a performance evaluation test.

  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 21 such as a transparent adhesive tape, as shown in FIG. And is bonded and fixed to a display device 22 (for example, various display devices such as a liquid crystal display and an EL display).

  Thereby, the display apparatus 22 can be functioned as a display apparatus with a touch panel (touch panel device) by mounting the touch panel 1 on the display apparatus 22 as one form of the input device.

  As described above, the touch panel 1 of the present embodiment avoids the lead-out wiring region E2 of the lead-out wiring portion 18 of the first electrode 13 and the second electrode 14 on the operation surface 11b of the substrate 11 and at least the operation region E1. The cover member 19 is disposed so as to cover a part of the cover member 19, and the surface of the cover member 19 and the surface 3 a of the housing portion 3 are flush with each other up to a step portion with the substrate 11 generated by the placement of the cover member 19. The outer edge of the substrate 11 is sandwiched from above and below by insert injection molding using a resin material.

  As a result, it is possible to shield the lead-out wiring portion 18 without providing a decorative layer that shields the lead-out wiring portion 18 from being visible from the outside, leading to a reduction in manufacturing cost and an adhesive layer as in the conventional device. Thus, a highly reliable touch panel can be provided that does not cause the substrate 11 to be detached from the housing 3 due to a strong impact such as a drop, as in the fitting structure by.

  Moreover, if the shape of the cover member 19 is designed to be an arbitrary shape such as a circle or a polygon, the design design can be arbitrarily changed by changing only the shape of the cover member 19 while the sensor unit 2 is shared. Can do.

  Further, 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 whole 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.

Further, in the conventional structure, it is necessary to provide a decorative portion so that the lead-out wiring portion 18 is not visually recognized from the outside and to have a shape in which the outer shape of the cover member 19 is extended to the location of the decorative portion. Since the cover member 19 is sandwiched so as to cover the portion of the wiring portion 18 with the housing portion 3, the size of the cover member 19 can be reduced.
In particular, when the cover member 19 is made of a glass material, a plurality of pieces are taken from a single glass plate. However, since the cover member 19 itself can be made smaller, the number of pieces that can be taken increases and the manufacturing cost can be reduced.

  Further, when a transparent resin material is used for the cover member 19, a protrusion 19a that functions as a fitting portion with the housing portion 3 is easily formed in an arbitrary shape by resin molding at the contact portion with the housing portion 3. Therefore, when the touch panel 1 is dropped, it is possible to prevent the cover member 19 from falling off from the casing 3 when the projection 19a increases the bonding area (contact area) with the casing 3. .

DESCRIPTION OF SYMBOLS 1 ... Touch panel 2 ... Sensor part 3 ... Housing | casing part 3a ... Front surface 3b ... Operation button 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 ... Crossing part 16 ... Insulating layer 17 ... Bridge wiring 18 ... Lead-out wiring part 19 ... Cover member (19a ... protrusion)
20 ... Adhesive layer E1 ... Operation area E2 ... Lead-out wiring area

Claims (5)

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,
A cover member is provided on the surface of the substrate so as to cover at least a part of the operation region while avoiding the lead-out wiring portion of the first electrode and the second electrode,
The casing portion is insert injection molded with a resin material so as to sandwich the outer edge portion of the substrate from above and below so as to be flush with the cover member without a step between the cover member and the substrate. Touch panel characterized by. The touch panel as set forth in claim 1, wherein the housing portion is formed so as to cover at least a surface of the lead-out wiring portion. The touch panel according to claim 1, wherein the cover member is a glass material. The touch panel according to claim 1, wherein the cover member is a transparent resin material. The touch panel according to claim 4, wherein a protrusion is formed at a contact portion of the cover member with the housing portion.

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