JP2018112807A - Cover glass and touch panel device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cover glass having a region whose shape changes through a touch operation, in the cover glass which receives the touch operation from a user.SOLUTION: A cover glass 12 is the cover glass configured to receive a touch operation from a user on a first major surface 20, and includes at least one flexible operation part 30 formed at a position corresponding to a touch operation region on which the user performs some kind of touch operation. In the flexible operation part 30, a curved part 32 having a convex curved surface shape is formed on the first major surface side 20. On a second major surface 22 side of the flexible operation part 30, a first concave part 34 including at least a curved surface shape is formed. Further, the cover glass has a compression stress layer 24 formed on the first major surface 20 and the second major surface 22, and is curved convexly toward the first major surface 20 side.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a cover glass that can be applied to a touch panel or the like that receives a touch operation from a user, and more particularly to a cover glass that allows a user to obtain an operational feeling and a touch panel device including the same.

  In recent years, a touch panel has been adopted in a wide range of fields as an interface when a user operates a device because of an advantage that an intuitive operation is possible. The cover glass for the touch panel is arranged on the side where the touch panel is exposed to the user, and is configured to accept a touch operation performed while the user visually recognizes a touch operation area where icons and the like are displayed. Due to the improved design due to the flatness of the cover glass and high transparency, the movement to replace with a touch panel has spread to devices that conventionally used physical buttons and keyboards. For example, there are air conditioners installed in automobiles, center consoles for controlling audio, etc., and operation panels equipped with household electrical appliances that are operated by touch panels. In portable electronic devices such as smartphones, Most operations can be performed with the touch panel.

  However, a cover glass having a flat shape is often used, and it has been difficult to differentiate in terms of design. Furthermore, when a visually handicapped person operates, or when operating in a situation where the touch operation area cannot be viewed accurately, a malfunction may occur.

  Thus, there is a technique in the related art that allows a region touched by touch to be recognized by forming a recess in a cover glass disposed on the surface of the touch panel (for example, Patent Document 1). By forming such a recess, the user can easily recognize the area to be touched by the touch of a finger, so that it is possible to perform an accurate touch operation without looking at the screen.

Japanese Patent No. 5881414

  However, the glass substrate as described above can determine the area to be touched, but when the user touches the touch panel, it may not be known whether the device recognizes the touch operation. It was. Compared with a physical switch, the touch panel does not change the tactile sensation transmitted to the user's finger during a touch operation. For this reason, it is not known whether the touch operation is actually recognized by the device, or there is a risk of malfunction.

  The objective of this invention is providing the cover glass and touch panel apparatus which have the area | region where a shape change is carried out by touch operation in the cover glass used for the touch panel etc. which accept the touch operation from a user.

  The cover glass according to the present invention is a cover glass configured to receive a touch operation from a user on the first main surface, and is formed at a position corresponding to a touch operation area where the user performs some touch operation. And at least one flexible operation unit. The flexible operation part is formed with a curved part having a convex curved surface on the first main surface side. A first recess including at least a curved surface is formed on the second main surface side of the flexible operation unit. Further, the cover glass has a compressive stress layer formed on the first main surface and the second main surface, and is curved in a convex shape toward the first main surface.

  By forming the first recess, a difference occurs in compressive stress between the first main surface and the second main surface in the flexible operation unit. The compressive stress on the second main surface side of the flexible operation portion increases, and a convex curved portion is formed on the first main surface side. The user can visually or tactilely recognize the position to be touched by the bending portion. In addition, the bending portion has a thin plate thickness. When a load is applied from the first main surface side, the bending portion deforms by bending toward the second main surface side, and when the load is removed from the bending portion, the bending portion is spontaneously formed. It is configured to return to its original shape. By providing the flexible operation unit, the user can obtain feedback (click feeling) by tactile sensation like a push button switch such as a membrane switch even in a cover glass constituted by a single glass substrate. .

  Furthermore, by bending the cover glass itself in the same direction as the convex direction of the bending portion, the deformed bending portion is more likely to return to the original shape. In order to control the deformation of the curved portion, it is necessary to adjust the compressive stress and the size of the first concave portion as described above. However, the curved portion is easily deformed by curving the cover glass itself. For this reason, control of compressive stress becomes easy and the freedom degree of design of a cover glass can be raised.

  In addition, it is preferable that a second recess is further provided on the first main surface side of the flexible operation unit. The second recess has a curved portion formed on the bottom surface. Further, the surface area of the second recess is formed to be different from the surface area of the first recess. By forming the first concave portion and the second concave portion so as to have different surface areas, the compressive stress of the first main surface and the second main surface cannot be balanced, and a curved portion is formed on the bottom surface of the second concave portion. It is formed. The surface areas of the first recess and the second recess can be made different by changing the depth and shape of each recess. In addition, the surface area of the recessed part area | region in this invention is a total area of the bottom face and side surface of a recessed part.

  Moreover, it is preferable that the elastic member is arrange | positioned at the 1st recessed part. The elastic member is configured to be elastically deformed in accordance with the deformation of the flexible operation unit. By arranging the elastic member in this way, the ease of deformation of the flexible operation unit can be controlled. In addition, by using the restoration of the elastic member when the load from the flexible operation unit is removed, the flexible operation unit can easily return to the original shape. Furthermore, by disposing the elastic member, even if the cover glass is broken, it is possible to prevent the glass fragments from scattering by the glass fragments adhering to the elastic member.

  ADVANTAGE OF THE INVENTION According to this invention, in the cover glass which receives the touch operation from a user, it becomes possible to provide the cover glass and touch panel apparatus which have the area | region where a shape changes by touch operation.

It is a figure which shows the controller with which the cover glass which concerns on one Embodiment of this invention is arrange | positioned. It is a figure which shows a cover glass. It is a figure which shows another embodiment of a cover glass. It is a figure which shows the manufacturing method of a cover glass. It is a figure which shows the manufacturing method of a cover glass.

  From here, one Embodiment of this invention is described using drawing. FIG. 1A illustrates a touch panel controller 10 for operating an electronic device such as a television. The controller 10 includes at least a cover glass 12, a touch panel 14, and a display 16. Further, the controller 10 includes a flexible operation unit 30 and an information display unit 60 on the operation area. The information display unit 60 is an area where operation information is displayed by a flat panel display or the like. The flexible operation unit 30 is formed on the cover glass 12 and is an area for the user to perform some touch operation.

  Subsequently, each component will be described with reference to FIG. 1B which is a schematic sectional view of the controller 10. The cover glass 12 is a glass substrate disposed on the surface exposed to the user side of the controller 10. The cover glass 12 is a single glass substrate configured to protect the controller 10 from an impact or the like, and the user touches the cover glass 12 when operating the controller 10. The cover glass 12 is a glass substrate having a plate shape, and in this embodiment, an aluminosilicate glass is used. The plate thickness of the cover glass 12 is preferably 0.3 to 1.5 mm.

  The cover glass 12 has a first main surface 20 and a second main surface 22. The first main surface 20 is a main surface exposed to the user, and the second main surface 22 is a main surface opposite to the first main surface 20. A compressive stress layer 24 is formed on both the first main surface 20 and the second main surface 22. The compressive stress layer 24 is a layer having a higher compressive stress than the internal region of the cover glass 12 formed by a known method such as an ion exchange method. The compressive stress layer 24 formed on the first main surface 20 and the second main surface 22 is formed under the same conditions, and there is no substantial difference in the strength and depth of the compressive stress.

  Further, the cover glass 12 is curved in a convex shape toward the first main surface 20 side. The curvature radius of the cover glass 12 can be set as appropriate. Examples of the method of curving the cover glass 12 include a method in which the cover glass 12 is heated to the softening point and molded. Further, it is possible to bend along the curved display 16 and the touch panel 14.

  The touch panel 14 is arrange | positioned at the lower part of the cover glass 12, and is comprised so that the area | region which the user touched may be detected. As a detection method of the touch panel 14, a known detection method such as a resistance film method or a capacitance method can be adopted. The touch panel 14 can be formed integrally with the cover glass 12 and the display 16.

  The display 16 is a flat panel display such as a liquid crystal panel or an organic EL panel, and displays an image on the information display unit 60 or displays an icon indicating a touch area at a position corresponding to the flexible operation unit 30. Configured as follows. Alternatively, the icon may be displayed using a transparent substrate and a backlight on which the icon is printed in advance.

  The cover glass 12 has the flexible operation part 30 in the area | region where a user performs touch operation. The flexible operation unit 30 preferably displays an icon or the like so that the user can easily see it. The flexible operation unit 30 is configured to bend and deform when pressed with a finger or the like by a touch operation from a user. When the finger is removed, the original shape is restored.

  The flexible operation unit 30 has a curved portion 32 having a convex curved shape on the first main surface 20 side. The curved surface shape of the bending portion 32 allows the user to recognize the touch operation area visually or tactilely. In addition to the flexible operation unit 30, the touch operation region may be formed in the information display unit 60 or in the peripheral region of the flexible operation unit 30.

  A recess 34 is formed on the second main surface 22 side of the flexible operation unit 30. The recess 34 is a region recessed in a concave shape toward the first main surface 20 side, and is formed to include at least a curved surface shape. The concave portion 34 can be formed in a desired shape, and is preferably formed larger than the corresponding icon in consideration of visibility. Moreover, the recessed part 34 can be formed so that a taper shape may be included by forming by the etching process mentioned later, As a taper angle, 10-60 degrees is preferable. Here, the taper angle refers to the inclination angle of the rising surface (side surface) with respect to the bottom surface of the recess 34. By forming the taper shape, the possibility that the flexible operation unit 30 is damaged at the time of deformation can be reduced.

  By forming the recess 34, the area of the compressive stress layer forming region on the second main surface 22 side in the flexible operation unit 30 becomes larger than that on the first main surface 20 side. As a result, the total volume of the compressive stress layer is larger on the second main surface 22 side than on the first main surface 20 side, and the compressive stress generated on the second main surface 22 side is the first main surface. It becomes larger than the compressive stress generated on the 20 side. According to the applicant's research, the compression stress of the first main surface 20 and the second main surface 22 cannot be balanced in this way, so that the bottom surface of the concave portion 34 is curved convexly toward the first main surface side. In addition, it is known that the probability that the curved portion 32 is formed is high. At this time, the difference in compressive stress between the first main surface and the second main surface in the flexible operation unit 30 is preferably 10 to 1000 MPa, and the curvature radius of the curved portion 32 is adjusted by the difference in compressive stress. Is possible. Moreover, since the surface area of the recessed part 34 can be increased by forming the side surface of the recessed part 34 to have a tapered shape, the compression stress of the second principal surface 22 and the compression of the first principal surface 20 are achieved. It becomes easy to make a difference in stress.

  Since the thickness of the flexible operation unit 30 is smaller than that of the peripheral region due to the recess 34, when a load is applied to the flexible operation unit 30 from the first main surface 20 side by the user's touch operation, As shown in FIG. 2A, the bending portion 32 is deformed. At this time, since a space is formed in the lower portion by the concave portion 34, the flexible operation portion 30 is bent and deformed in a concave shape toward the second main surface 22 side. In order for the flexible operation unit 30 to be suitably deformed, the recess 34 is preferably formed so that the plate thickness of the flexible operation unit 30 is 50 to 200 μm. When the plate thickness of the flexible operation unit 30 is larger than 200 μm, the flexible operation unit 30 is hardly deformed due to the rigidity of the cover glass 12. Moreover, since the intensity | strength of the cover glass 12 will fall when the flexible operation part 30 becomes less than 50 micrometers, there exists a possibility that it may be damaged at the time of touch operation. In addition, the flexible operation unit 30 is extremely thin, but since the compressive stress layer 24 is formed, there is a low possibility of being damaged due to deformation.

  When the user removes his / her finger from the flexible operation unit 30, the flexible operation unit 30 spontaneously returns to the original shape from the deformed state (see FIG. 2B). For this reason, also in the cover glass 12 comprised with the single glass substrate, the user can obtain a click feeling like pushbutton switches, such as a membrane switch. The user can easily confirm whether the touch operation has been recognized due to the shape change of the flexible operation unit 30, and can prevent the controller 10 from being erroneously operated. Since the flexible operation unit 30 automatically restores the original shape after the deformation, the touch operation can be repeatedly performed. Further, it is possible to control the radius of curvature and the amount of bending deformation of the bending portion 32 by adjusting the plate thickness and compressive stress value of the flexible operation portion 30.

  Moreover, the restoring force of the flexible operation part 30 improves because the cover glass 12 is curving convexly toward the first main surface 20 side. In order to deform the flexible operation unit 30 so as to obtain a click feeling, it is necessary to make a difference in compressive stress between the first main surface 20 and the second main surface 22. The dimensions need to be controlled. By curving the cover glass 12, the above control is facilitated, and the degree of freedom in designing the flexible operation unit 30 can be increased.

  The controller 10 of this embodiment employs a resistive film type touch panel, and is designed so that it is difficult to react when the user's finger just touches the touch panel. By setting the controller 10 to recognize the touch operation when the cover glass 12 and the touch panel 14 come into contact with each other when the flexible operation unit 30 is deformed, the risk of malfunction is reduced. Note that the cover glass 12 can also be applied to a capacitive touch panel or other types of touch panels. For example, if programming is performed so that the touch panel 14 detects a touch operation only when the flexible operation unit 30 is deformed, or if a sensor layer or the like that senses the strength of pushing into the touch panel 14 is provided, static It can also be used for the capacitance method.

  The cover glass 12 can be applied not only to a touch panel but also to an external cover of a physical switch such as a membrane switch. For example, in the membrane switch, the flexible operation unit 30 may be deformed at the upper part of the switch mechanism to push the contacts arranged at the lower part so that the contacts are brought into contact with each other. By applying a cover glass composed of a single glass substrate to the physical switch, the design can be improved.

  From here, another embodiment of the cover glass will be described with reference to FIG. FIG. 3 is a view showing a cover glass 121 according to another embodiment of the present invention. The cover glass 121 has a compressive stress layer 24 formed on the first main surface 20 and the second main surface 22. The cover glass 121 has the flexible operation unit 30 in a touch operation area where a user performs a touch operation. The flexible operation unit 30 has an operation recess 40 formed on the first main surface 20 side and a recess 34 formed on the second main surface 22 side.

  The operation concave portion 40 is a region recessed in a concave shape on the second main surface 22 side, and the curved portion 32 is formed at the bottom thereof. Since the configuration of the bending portion 32 is substantially the same as that of the above embodiment, detailed description thereof is omitted. The operation concave portion 40 preferably includes a curved surface shape, and more preferably has a tapered side surface. Further, the surface area of the operation recess 40 is formed to be smaller than the surface area of the recess 34. By forming the operation concave portion 40 and the concave portion 34 so as to have different surface areas, the compressive stress of the first main surface 20 and the second main surface 22 cannot be balanced. For this reason, the bottom surface of the operation concave portion 40 is curved in a convex shape, and the curved portion 32 is formed. In this embodiment, the balance of the compressive stress is lost by making the depth of the operation recess 40 shallower than the depth of the recess 34, but the recess 34 is formed shallower than the operation recess 40, The recess 40 and the recess 34 may be formed in different shapes.

  An elastic member 42 is disposed in the recess 34. The elastic member 42 is configured to be deformed according to the elastic deformation of the flexible operation unit 30. Further, the elastic member 42 is preferably made of a transparent material so that an icon displayed on the display 16 can be visually recognized, and polyethylene, polypropylene, or silicon resin can be used. By adjusting the elasticity of the elastic member 42, it is possible to adjust the amount of bending of the flexible operation unit 30 and the load necessary for deformation. Further, when the finger is released from the flexible operation unit 30, there is an effect that the flexible operation unit 30 can easily return to the original shape by using the restoring force of the elastic member 42. In addition, by disposing the elastic member 42, even if the flexible operation unit 30 is damaged, it is difficult for the fragments to adhere to the elastic member 42 and scatter, thereby increasing safety.

  Further, by including a transparent conductive member in the elastic member 42, it is possible to support a capacitive touch panel. As the transparent conductive member, organic conductive materials such as ITO and polythiophene, and metal nanowires can be used. Moreover, you may arrange | position a spacer under the cover glass as needed. As the spacer, transparent silica used for a liquid crystal substrate or the like can be used. By arranging the spacer, it is possible to control the amount of bending of the flexible operation unit 30 and the touch to the touch panel 14.

  Further, in the present embodiment, since the operation concave portion 40 is formed, the touch operation area is more easily understood by tactile sense. Further, since the operation recess 40 has a curved surface shape and a taper shape, there is no possibility that the user's finger is damaged during the touch operation.

  From here, the manufacturing method of the cover glass 12 is demonstrated using FIG. 4 (A)-FIG. 4 (D). The manufacturing method of the cover glass 12 in this embodiment includes a protective member forming step, a patterning step, an etching step, a chemical strengthening treatment step, and a bending step.

  In the protective member forming step, the main surface of the glass substrate 50 is covered with a protective film 52 having etching resistance. The glass substrate 50 is aluminosilicate glass, and the plate thickness is preferably 0.3 to 1.5 mm. The protective film 52 is configured to protect the main surface of the glass substrate 50 in the etching process described later, and has at least resistance to hydrofluoric acid. In addition to the protective film, a protective material such as a photosensitive resist material can be used.

  In the patterning step, as shown in FIG. 4A, the protective film 52 is removed from one main surface corresponding to a region where a recess is to be formed, and an opening is formed. As the patterning means, any means may be used as long as the acid-resistant member can be removed from the region to be etched. In this embodiment, patterning is performed using a laser device. In this embodiment, a pulse laser is used to remove only the protective film 52 without damaging the glass substrate 50. When a photosensitive resist is used as the acid-resistant member, patterning can be performed using photolithography.

  In the etching step, the glass substrate 50 is brought into contact with the etching solution to etch the region where the opening is formed. When etching the glass substrate 50, a single-wafer type etching apparatus for injecting an etching solution onto the glass substrate 50 being conveyed by a desired conveyance mechanism or the glass substrate 50 is immersed in an etching tank containing the etching solution. A batch type etching apparatus or the like can be used. As the etchant, an etchant containing at least hydrofluoric acid is preferably used. In addition to hydrofluoric acid, an inorganic acid such as hydrochloric acid or a surfactant may be added. By the etching process, the region not protected by the protective film 52 is etched, and the recess 34 is formed. The etching process is preferably performed until the thickness of the recess 34 is 200 μm or less.

  After forming the recess 34 by etching, the protective film 52 is removed from the glass substrate 50. When removing the protective film 52, the protective film 52 can be peeled by applying a physical force to the protective film 52. In addition, when a resist material is used, it can be removed by immersing the glass substrate 50 in a stripping solution.

  The chemical strengthening treatment step is a step of forming a compressive stress layer on the glass substrate 50. A chemical strengthening process is performed by the well-known method by immersing a glass substrate in the molten salt containing an alkali ion. In this embodiment, the chemical strengthening treatment was performed by immersing the glass substrate in a potassium nitrate solution heated to 400 ° C. for 4 hours. The heating temperature of potassium nitrate is preferably adjusted to 350 to 450 ° C., and the immersion time of the glass substrate is preferably about 2 to 20 hours. The depth of the compressive stress layer 24 is preferably adjusted to 5 to 50 μm. The first main surface 20 and the second main surface 22 are chemically strengthened under the same conditions, and the depth of the compressive stress layer 24 is substantially the same.

  By forming the compressive stress layer 24, a region facing the concave portion 34 is curved in a convex shape, and a curved portion 32 is formed (see FIG. 4C). By forming the concave portion 34 by etching, the possibility that the glass substrate 50 is damaged when the curved portion 32 is formed is reduced. In particular, the intersection of the recess 34 and the second main surface 22 is formed in a curved surface, so that the glass substrate 50 can be prevented from being damaged even when the flexible operation unit 30 is deformed.

  In the bending step, the glass substrate 50 is heated to near the softening point and is thermally deformed by pressing it against a mold set to a desired radius of curvature. After thermal deformation, the glass substrate 50 can be cooled, and if the glass substrate 50 has a thickness of 500 μm or less, it can be laminated along a touch panel component such as a curved display. Therefore, it is not necessary to provide a bending process.

  Moreover, when forming the operation recessed part 40 in the 1st main surface 20, after forming the recessed part 34 in the 2nd main surface 22, the glass substrate 50 is again protected with the protective film 52 (FIG. 5A). )reference.). Further, as shown in FIG. 5B, the protective film 52 on the first main surface 20 side is patterned to form an opening in a region where the operation recess 40 is formed. In this state, a cover glass having recesses formed on both main surfaces can be manufactured by performing etching again. Then, the flexible operation part in which the recessed part was formed in both main surfaces can be formed by performing a chemical strengthening process and a bending process. In this embodiment, the curved portion 32 is formed on the bottom surface of the operation recess 34 by forming the depth of the operation recess 40 shallower than the depth of the recess 40.

  The above description of the embodiment is to be considered in all respects as illustrative and not restrictive. The scope of the present invention is shown not by the above embodiments but by the claims. Furthermore, the scope of the present invention is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

10-controller 12-cover glass 14-touch panel 16-display 20-first main surface 22-second main surface 24-compressive stress layer 30-flexible operation portion 32-curved portion 34-recess 40-for operation Recess 42-Elastic member

Claims (4)

A cover glass configured to accept a touch operation from a user on the first main surface side,
At least one flexible operation unit formed at a position corresponding to a touch operation area where the user performs some touch operation;
In the flexible operation portion, a curved portion having a convex curved shape formed on the first main surface side;
A first recess formed so as to include at least a curved surface shape on the second main surface side;
Have
The cover glass is characterized in that a compressive stress layer is formed on the first main surface and the second main surface, and further curved in a convex shape toward the first main surface side. The curved portion is disposed on a bottom surface of a second recess formed on the first main surface side,
The cover glass according to claim 1, wherein a depth of the second recess is different from a depth of the first recess.   The cover glass according to claim 1, wherein a transparent elastic member is disposed in the first recess. A sensor module in which a sensing unit for detecting a touch device from a user and a display unit for displaying a touch operation area are stacked;
The cover glass according to any one of claims 1 to 3, which is disposed on the touch panel unit,
Touch panel device with

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