JP2018106507A - Manufacturing method of three-dimensional shaped touch panel sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a three-dimensional shaped touch panel sensor capable of reducing cost and obtaining positional detecting accuracy in a favorable manner.SOLUTION: A manufacturing method of a three-dimensional shaped touch panel sensor includes procedures sequentially: a step 1 for forming a ground layer on a surface of a planar substrate 11 having plasticity that can follow the deformation of the planar substrate 11; a step 2 for forming electrode patterns 12, 13 on the ground layer; and a step 3 for forming the planar substrate 11 on which the ground layer and the electrode patterns 12, 13 are formed into a three-dimensional shape. The procedures can include a step 4 for forming a plating layer on the electrode patterns 12, 13.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for manufacturing a touch panel sensor having a three-dimensional touch surface.

  Touch panels are widely used for operation units of electronic devices and the like. In the touch panel for such applications, a touch panel in which the touch surface has a three-dimensional curved surface shape has been proposed for the purpose of improving the operability or improving the aesthetics of the electronic device. As a specific example of a touch panel sensor serving as an operation input unit of such a touch panel, one disclosed in Patent Document 1 can be cited.

JP2013-257796A

  The conventional three-dimensional shape touch panel sensor disclosed in Patent Document 1 described above includes a film with a conductive electrode in which a conductive electrode surface region is formed on a film substrate, and a shape forming material made of acrylic resin, polycarbonate, or the like. It is an aspect formed by laminating or bonding.

  However, the three-dimensional shape touch panel sensor having such a configuration has a complicated structure and inevitably has a large number of manufacturing processes, and cost reduction including the necessity of process management in each manufacturing process. It is difficult to meet market demands.

  In view of such a problem, an object of the present invention is to provide a method for manufacturing a three-dimensional shape touch panel sensor that enables cost reduction. Another object is to obtain good position detection accuracy when a three-dimensional touch panel sensor is used.

  The manufacturing method of the three-dimensional shape touch panel sensor according to the present invention includes a step 1 of forming a base layer capable of following the deformation of the planar base material on the surface of the planar base material having plasticity, and the base layer A step 2 of forming an electrode pattern on the substrate, and a step 3 of forming the planar substrate on which the base layer and the electrode pattern are formed into a three-dimensional shape in this order. .

  By forming an electrode pattern directly on the surface of a flat substrate through an underlayer, a film with a conductive electrode and a shape-forming material are laminated or bonded as in a conventional three-dimensional touch panel sensor. Since it is not necessary, the structure is simplified and the number of manufacturing steps is reduced, so that the cost can be greatly reduced.

  In addition, when an electrode pattern is formed directly on the surface of a planar substrate without forming an underlayer, the electrode pattern cannot follow the expansion when the substrate is deformed into a three-dimensional shape. Ruptures or peels from the substrate, impairing the conductivity of the electrode pattern.

  The underlayer is formed by printing, coating, or the like on a planar base material, and has a deformation followability that does not break even when the base material partially reaches 150% or more. Those are preferred. When an electrode pattern is formed on such an underlayer, even if the planar substrate (and the underlayer) is stretched by the interposition of the underlayer, the electrode pattern and the underlayer are Since the electrode pattern follows the deformation without causing peeling, the electrode pattern is not broken or peeled off.

  In this invention, after the said process 3, you may further include the process 4 which forms a plating layer on the said electrode pattern.

  By further forming a plating layer on the electrode pattern, the conductivity of the electrode pattern can be improved. As a result, a signal for position detection can be sensed with high sensitivity, so that the position detection accuracy when using the three-dimensional touch panel sensor can be improved as compared with the case where there is no plating layer.

  In the present invention, the electrode pattern may be formed by printing a conductive ink. Further, the conductive ink binder may contain a flexible material.

  By forming an electrode pattern by printing using a plate for forming an electrode pattern of a desired shape, the electrode pattern can be obtained easily and inexpensively, so that the manufacturing cost can be suitably reduced. it can.

  In the present invention, the foundation layer and the electrode pattern may be formed on both surfaces of the planar substrate.

  An undercoat layer is formed on both surfaces of the planar substrate, an X-direction electrode pattern for detecting an operation position in the X direction on one surface, and an operation position in the Y direction on the other surface. By forming the Y-direction electrode pattern for detecting a grid pattern, a capacitive touch panel can be suitably obtained.

  In the present invention, the electrode pattern may be formed on the planar substrate in such a manner that an amount of deformation when the planar substrate is deformed into a three-dimensional shape is expected in advance.

  Optimize the shape after three-dimensional shaping, such as by forming an electrode pattern that anticipates the amount of deformation in a flat state, so that the pitch of the electrode pattern after three-dimensional shaping can be made uniform Can do.

  In the present invention, the electrode pattern is linear and may include a wavy line, zigzag line, or serpentine line part.

  By forming the electrode pattern in such a shape, the electrode pattern can follow the elongation of the base material and the base layer when performing three-dimensional processing, so that the breakage and peeling of the electrode pattern are more effective. Can be prevented.

  In the present invention, the outer shape of the planar base material may be a shape corresponding to a three-dimensional shape to be molded.

  By reducing the difference in the distance from the end portion to the three-dimensionally processed portion, it is possible to suppress a difference in elongation caused by material removal of the planar base material.

  According to the manufacturing method according to the present invention, it is possible to manufacture a three-dimensional shape touch panel sensor whose cost is significantly reduced as compared with the conventional method. In addition, when a three-dimensional touch panel sensor is used, good position detection accuracy can be obtained.

The example of the three-dimensional shape touch panel sensor manufactured with the manufacturing method which concerns on this invention is shown. The expansion | extension difference in the case of shape | molding a spherical-shaped three-dimensional shaping | molding part on a square planar base material is shown. An example in which the outer shape of the planar substrate is a shape corresponding to the deformation direction of the three-dimensional shape to be molded will be shown. The another example of the electrode pattern which concerns on this invention is shown.

  A three-dimensional touch panel sensor 10 according to an embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 shows a three-dimensional touch panel sensor 10 according to an embodiment of the present invention. The three-dimensional shape touch panel sensor 10 has a hemispherical convex portion 11a on a rectangular base material 11, and uses a grid-like X-direction electrode pattern 12 and Y-direction electrode pattern 13, and is well-known. By performing detection based on the electrostatic capacity method, a sensor unit for detecting the position of the operating body in contact with or close to the convex portion 11a is obtained. In the following description, the X-direction electrode pattern 12 and the Y-direction electrode pattern 13 may be collectively referred to as “electrode patterns”.

  The planar base material 11 having plasticity for forming the three-dimensional shape touch panel sensor 10 is a sheet shape having plasticity that can be molded into a three-dimensional shape using a vacuum pressure molding die or a stamping molding die. Or it is a film-like base material. As the material for the planar substrate 11, for example, polycarbonate (PC), polyethylene terephthalate (PET), polypropylene (PP), polyethylene (PE), polyamide (PA), acrylic, and the like are suitable. In the three-dimensional touch panel sensor 10 according to the present embodiment, a PC is used as the base material 11.

  The underlayer is formed by printing or applying a transparent ink compatible with polyester-based insert molding, and its thickness is approximately 12 μm, so that it does not break even when the substrate partially reaches 150% or more. It has the following characteristics of deformation. When an electrode pattern is formed on such an underlayer, even if the planar substrate 11 (and the underlayer) is stretched due to the interposition of the underlayer, the electrode pattern and the underlayer are not separated. Since the electrode pattern follows the deformation without causing peeling, the electrode pattern does not break or peel off.

  Each of the X-direction electrode pattern 12 and the Y-direction electrode pattern 13 is formed by printing a conductive ink made of a silver paste using a plate for forming the shape shown in the figure, and its thickness is approximately 10 μm. is there. Thus, an electrode pattern can be obtained easily and inexpensively by forming an electrode pattern by printing. The conductive ink binder may contain a flexible material. By using such a conductive ink, it is possible to more effectively suppress breakage and peeling of the electrode pattern. In addition to printing, the electrode pattern may be formed by a method such as etching.

  In the three-dimensional shape touch panel sensor 10, the X-direction electrode pattern 12 is formed on one surface and the Y-direction electrode pattern 13 is formed on the other surface so as to form a lattice shape. When such a grid-like electrode pattern is formed on the three-dimensional shape touch panel sensor 10, when the electrode pattern is formed in parallel so that the straight line forms a grid shape when the base material 11 is in a planar state, the following is performed. Two problems arise.

  The first problem is the difference in the degree of expansion depending on the part during three-dimensional processing.

  There are the following two methods for forming the planar substrate 11 into a three-dimensional shape. One is a method in which the base material 11 is sucked from the mold side to form a concave spherical shape so that the base material 11 is in close contact with the concave spherical shape mold, and the other is a convex spherical shape. In this method, the base material 11 is brought into close contact with the mold, and the base material 11 is protruded by the mold to form a convex spherical shape.

  In the case of the method of forming into a concave spherical shape, since the base material 11, the underlayer, and the electrode pattern are stretched most at the top of the spherical surface, the pitch is wide near the top and the pitch is relatively near the periphery. Since it becomes narrow, the pitch after the three-dimensional forming process becomes non-uniform. On the other hand, in the case of the method of forming a convex spherical shape, the base material 11, the underlayer and the electrode pattern are stretched most in the peripheral portion of the spherical surface, so that the pitch is wide near the peripheral portion and relative to the top portion. The pitch becomes narrower.

  As a countermeasure to this first problem, in the case of the method of forming into a concave spherical shape, the pitch of the lattice located at the top is dense, and the pitch of the lattice located at the peripheral portion is coarsened, so that Can be made uniform in pitch. In the case of the method of forming into a convex spherical shape, on the contrary, the pitch of the grating located at the peripheral part is made dense, and the pitch of the grating located at the top part is made rough so that the pitch after forming becomes uniform. can do.

  The second problem is a difference in stretch caused by material removal of the planar substrate. For example, when the three-dimensional touch panel sensor 10 is formed from the rectangular base material 11 as shown in FIG. 2, the distance A from the corner portion to the three-dimensional (spherical) molded portion 14 is 3 from the side portion. Since the base material 11 is stretched more in the vicinity of the B portion than in the vicinity of the A portion due to being longer than the distance B to the dimension forming portion 14, the lattice pitch in the vicinity of the B portion becomes wider.

  As a countermeasure to this second problem, when forming the electrode pattern with the substrate 11 in a flat state, the amount of extension of the B portion is estimated in advance, and the pitch near the B portion is set to be greater than the pitch near the A portion. However, if a grid-like electrode pattern is formed by appropriately reducing the pitch, the pitch becomes uniform after the projections 11a are formed.

  The manufacturing method according to the present invention includes three-dimensional shapes such as a spherical convex shape and a concave shape, an elliptical convex shape and a concave shape, a truncated cone, a kamaboko shape, a square shape, a corrugated shape, and the like. Various shapes are targeted. When such a concavo-convex shape is formed, the electrode pattern formed on the surface of the base material 11 in a planar state is deformed along with the three-dimensionalization. When forming the electrode pattern, it is preferable to form a pattern on the planar substrate 11 in advance of the amount of deformation required to deform from the planar shape to these various three-dimensional shapes.

  Further, as another response to the second problem, the outer shape of the planar substrate is molded 3 for the purpose of reducing the difference in distance from such an end portion to the three-dimensional molded portion 14. The shape may correspond to a dimensional shape. That is, when the hemispherical convex portion 11a is formed as in the above-described embodiment, it is preferable to use the base material 11 formed in a circular shape in advance as shown in FIG. As described above, by setting the outer shape of the planar base material 11 to a shape corresponding to the shape of the three-dimensional molded portion 14, it is possible to suppress the influence of the expansion difference due to the shape of the base material 11.

The three-dimensional shape touch panel sensor 10 is obtained by the following process.
(Step 1) A transparent ink corresponding to polyester-based insert molding was printed on both sides of a square planar PC substrate as the planar substrate 11 to form an underlayer.
(Step 2) An X-direction electrode pattern 12 is printed on a base layer on one side using a conductive ink made of silver paste, and then silver is also applied on the base layer on the other side. Using the conductive ink made of paste, the above-described X-direction electrode pattern 12 and the Y-direction electrode pattern 13 having a lattice shape were printed.
(Step 3) The flat substrate 11 on which the electrode pattern obtained in Step 2 is formed is attached to a concave spherical mold (not shown), and the inside of the mold is sucked and depressurized, whereby the substrate 11 is obtained. Was formed into a hemispherical shape.

  In the present embodiment, since the method of forming into a three-dimensional shape by sucking into a concave spherical shape in Step 3 is adopted, the top of the hemispherical surface extends more than the surrounding area. Therefore, as shown in a partial enlarged view in FIG. 1B, in the planar state, the X-direction electrode pattern 12 and the central portion P0 have a pitch P1 that is smaller than the surrounding pitch P0. A Y-direction electrode pattern 13 was formed.

  As described above, instead of the molding method of sucking into the concave spherical shape, it can be molded by pushing with a convex spherical mold. In this case, unlike the case of the above-described embodiment, the peripheral portion of the hemispherical surface extends more greatly at the top portion. Therefore, contrary to the above-described embodiment, the pitch of the peripheral portion in the planar state [FIG. It is preferable to form a grid-like electrode pattern at a pitch smaller than that of the central part [part P1 in FIG. 1]] [part P0 in FIG.

  In addition, the curve was corrected in advance in consideration of the difference between the distance from the corner of the substrate and the distance from the side. As a result, when it is formed into a hemispherical shape, an electrode pattern having a pitch such as shown in FIG.

  When the three-dimensional shape touch panel sensor 10 thus obtained is connected to a known detection circuit (not shown) for detecting a capacitance value and operated as a capacitance touch panel, contact or proximity is obtained. The position of the operating body to be detected could be detected well.

  After forming into a hemispherical shape, if necessary, a copper plating layer may be formed on the surface of the electrode pattern by an electroless plating method. By doing so, the conductivity of the electrode pattern can be improved and a signal for position detection can be satisfactorily sensed, so that the position detection accuracy when using the three-dimensional shape touch panel sensor 10 is improved. Can do. Note that the plating on the electrode pattern is not limited to copper, and other metals can be plated.

  FIG. 4 is a diagram showing another example of the X-direction electrode pattern 12 and the Y-direction electrode pattern 13, and FIG. 4A shows an example in which the electrode pattern is a wavy line composed only of a curve. ) Shows an example in which the electrode pattern is a zigzag line formed by connecting relatively short straight lines, and FIG. 4C shows an example in which the electrode pattern is a meander line formed by a combination of a straight part and a curved part. ing. By forming the electrode pattern in such a shape, the electrode pattern better follows the extension of the base material 11 and the base layer during three-dimensional processing, so that the breakage and peeling of the electrode pattern are more effective. It is preferable at the point which can prevent.

  In the present embodiment, an example in which a spherical three-dimensional shape is formed is shown, but the three-dimensional shape is not limited and can correspond to various three-dimensional shapes.

  The present invention can be suitably used in the manufacture of a three-dimensional touch panel sensor used for an input operation to an electronic device or the like.

DESCRIPTION OF SYMBOLS 10 3D-shaped touch panel sensor 11 Base material 11a Convex part 12 X direction electrode pattern 13 Y direction electrode pattern 14 3D shaping part

Claims (7)

Forming a base layer capable of following the deformation of the planar substrate on the surface of the planar substrate having plasticity; and
Forming an electrode pattern on the underlayer; and
Step 3 of forming the planar substrate on which the base layer and the electrode pattern are formed into a three-dimensional shape;
A three-dimensional shape touch panel manufacturing method, comprising:   The method for manufacturing a three-dimensional touch panel according to claim 1, further comprising a step 4 of forming a plating layer on the electrode pattern after the step 3.   The method for manufacturing a three-dimensional touch panel according to claim 1, wherein the electrode pattern is formed by printing a conductive ink.   The method for manufacturing a three-dimensional touch panel according to any one of claims 1 to 3, wherein the base layer and the electrode pattern are formed on both surfaces of the planar substrate.   5. The electrode pattern according to claim 1, wherein an electrode pattern in which a deformation amount when the planar substrate is deformed into a three-dimensional shape is anticipated is formed on the planar substrate. The manufacturing method of the three-dimensional shape touch panel of any one of these.   6. The electrode pattern according to claim 1, wherein the electrode pattern is linear and includes a wavy line shape, a zigzag line shape, or a meandering line shape. A method for manufacturing a three-dimensional touch panel.   The method for manufacturing a three-dimensional touch panel according to any one of claims 1 to 6, wherein an outer shape of the planar base material is a shape corresponding to a three-dimensional shape to be molded. .

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