JP3825487B2 - Transparent touch panel - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a transparent touch panel that is arranged on a screen such as an LCD (liquid crystal display) or a CRT (CRT) and performs position input by pressing from above with a finger or a pen in accordance with an instruction of the fluoroscopic screen. is there.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a transparent touch panel, as shown in FIG. 2 , a transparent conductive film 2 made of indium tin oxide (ITO) or the like and a parallel paste made of silver paste or the like are formed on the upper surface of a transparent insulating substrate 1 such as a glass plate. The lower electrode 4 having a pair of bus bars 3 and the upper electrode 8 having a conductive film 6 and a bus bar 7 similar to those described above formed on the lower surface of a transparent flexible insulating base material 5 such as a polyester film are connected to the conductive film 2. , 6 are interleaved with a spacer 9 such as a dot shape so that the direction between the bus bars 3 of the lower electrode 4 and the direction between the bus bars 7 of the upper electrode 8 are orthogonal to each other, and the peripheral portion is covered with an adhesive layer 10 such as a double-sided tape. There is a bonded analog resistive film type. The bus bars 3 and 7 are usually connected to the external terminals by providing a routing circuit 11 on the lower electrode 4 and / or the upper electrode 8 or the like.
[0003]
As shown in FIG. 3 , the principle of the analog resistive film type transparent touch panel is that a point P on both conductive films 6 and 2 is point-contacted by pressing an arbitrary point P on the upper electrode 8 with a finger or a pen. When a voltage is applied to the upper electrode 8 and no voltage is applied to the lower electrode 4, a potential gradient is generated in the X direction in the conductive film 6 of the upper electrode 8. voltage e x obtained by dividing the point P occurs, the voltage e x is detected from the divided voltage output terminal 12 of the lower electrode 4. Here, assuming that the coordinates of the point P are (x, y), the distance between the bus bars 7 of the upper electrode 8 is L 1 , and the voltage between the bus bars 7 is E, the relationship of e x / E = x / L 1 The x coordinate of the point P can be obtained from the voltage e x . Also, by not applying a voltage to the applied voltage and the upper electrode 8 with respect to the lower electrode 4, cause the voltage e y obtained by dividing the point P on the conductive film 2 of the lower electrode 4, the voltage e y in , Detected from the partial pressure output end 13 of the upper electrode 8. Here, if the distance between the bus bars 3 of the upper electrode 8 L 2, and E the voltage between the bus bars 3, the relationship of e y / E = y / L 2, determine the y-coordinate of the point P from the voltage e y be able to.
[0004]
Incidentally, as shown in FIG. 4 , the transparent touch panel is housed in the housing of the input device, and the upper surface of the upper electrode 8 is exposed from the window portion 14 of the housing. However, the adhesive layer 10 may be contaminated by taking in dust and bubbles, and the window portion 14 of the housing is positioned on the inner side of the adhesive layer 10 of the transparent touch panel in order to conceal this appearance defect. That is, the upper electrode 8 and the lower electrode 4 can be electrically connected under the window frame 15 of the housing. For this reason, if the user touches the window frame 15 of the housing when performing an input operation, the upper electrode 8 is pressed by the window frame 15 and an erroneous input may occur.
[0005]
Therefore, in order to prevent this erroneous input, an insulation having a substantially uniform thickness in a solid pattern is formed in a frame-like region that is adjacent to the inside of the adhesive layer 10 between the upper electrode 8 and the lower electrode 4 of the transparent touch panel. Layer 16 was provided (see FIGS . 5 and 6 ).
[0006]
[Problems to be solved by the invention]
However, when the transparent touch panel is slid with a finger or a pen at the position where the insulating layer 16 is formed or the vicinity thereof, the conductive film 6 of the upper electrode 8 exerts a strong pressure locally on the inner upper corner of the insulating layer 16. Although it is damaged by the addition, since this scratch is continuous, the conductivity of the conductive film 6 and its uniformity were easily impaired (see FIG. 7 ). Therefore, there is a problem that linearity (linearity) is impaired, and the finger or pen movement 17 on the transparent touch panel cannot be input as it is, resulting in a different input content 18 (see FIG. 8 ).
[0007]
Accordingly, an object of the present invention is to solve the above-described problem and to provide a transparent touch panel that does not lose linearity.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the transparent touch panel of the present invention is formed in a frame-shaped region adjacent to the inside of the adhesive layer between the upper electrode and the lower electrode, and the inner end is formed in an intermittent comb-tooth shape. The insulating layer was provided.
[00 09 ]
The transparent touch panel according to the present invention will be described in detail below.
[00 10 ]
FIG. 1 is a plan view showing a transparent touch panel according to the present invention. 3 is a bus bar, 7 is a bus bar, 10 is an adhesive layer, and 16 is an insulating layer.
[00 11 ]
Insulating substrates include glass plates such as soda glass, borosilicate glass, and tempered glass, engineering plastics such as polycarbonate, polyamide, and polyether ketone, acrylic, polyethylene terephthalate, and polybutylene terephthalate. A transparent resin plate or a transparent film is used.
[00 12 ]
As the flexible insulating substrate, engineering plastics such as polycarbonate, polyamide, and polyether ketone, transparent films such as acrylic, polyethylene terephthalate, and polybutylene terephthalate are used. A hard coat layer may be formed on the upper surface of the flexible insulating substrate. Examples of the hard coat layer include inorganic materials such as siloxane-based resins, and organic materials such as acrylic epoxy-based and urethane-based thermosetting resins and acrylate-based photocurable resins. The thickness of the hard coat layer is suitably about 1 to 7 μm. In addition, the flexible insulating base material may be subjected to non-glare treatment on the upper surface in order to prevent light reflection. For example, the flexible insulating base material or the hard coat layer is processed to have irregularities, or fine particles such as extender pigments, silica, and alumina are mixed in the hard coat layer. Furthermore, the flexible insulating base material may be a laminated body in which a plurality of films are overlapped instead of a single film.
[00 13 ]
As conductive films, metal oxide films such as tin oxide, indium oxide, antimony oxide, zinc oxide, cadmium oxide, indium tin oxide (ITO), composite films mainly composed of these metal oxides, gold, silver, copper There are metal films such as tin, nickel, aluminum and palladium. Further, the conductive film may be formed in multiple layers. As a method for forming the conductive film, vacuum deposition, sputtering, ion plating, CVD, or the like is used.
[00 14 ]
As the bus bars 3 and 7, a conductive paste such as a metal such as gold, silver, copper, nickel, or carbon is used. Examples of methods for forming the bus bars 3 and 7 include screen printing, offset printing, gravure printing, flexographic printing, and other printing methods, a photoresist method, and a brush coating method.
[00 15 ]
The spacer is formed on either the conductive film of the lower electrode or the conductive film of the upper electrode. For example, transparent photo-curing resins such as melamine acrylate resin, urethane acrylate resin, epoxy acrylate resin, methacryl acrylate resin, acrylate resin such as acrylic acrylate resin, and polyvinyl alcohol resin are formed into fine dots by a photo process. Can be obtained. Also, a large number of fine dots can be formed by a printing method to form a spacer.
[00 16 ]
As the adhesive layer 10, an insulating adhesive made of double-sided tape, acrylic resin, epoxy resin, phenol resin, vinyl resin, or the like is used. The two electrodes are bonded together after the adhesive layer 10 is formed on both or only one of the peripheral edge of the upper electrode and the peripheral edge of the lower electrode. In addition, when the routing circuit is formed as one electrode, the bus bar formed on the other electrode is connected to the routing circuit through a conductive substance, and therefore, an insulating adhesive layer is provided at the connection portion. 10 is not provided.
[00 17 ]
As the insulating layer 16, thermoplastic resin such as methacrylic acid ester resin, acrylic acid ester resin, polyethylene terephthalate resin, polybutylene terephthalate resin, polyamide resin, alkyd resin, melamine resin, urethane resin, epoxy resin, urea resin, poly Some are made of thermosetting resins such as siloxane resins, melamine acrylate resins, urethane acrylate resins, epoxy acrylate resins, acrylate resins such as methacryl acrylate resins, acrylic acrylate resins, and photo-curable resins such as polyvinyl alcohol resins. . Examples of the method for forming the insulating layer 16 include screen printing, offset printing, gravure printing, flexographic printing, and other printing methods, a photoresist method, a brush coating method, a coating method, and a dipping method. A single-sided adhesive tape may be used as the insulating layer 16. Further, the insulating layer 16 may be opaque if it is not exposed from the window portion 14 of the housing.
[00 18 ]
In addition, when coloring materials such as extender pigments, dyes, and pigments or inorganic compound particles such as silica, alumina, zirconia, and titanium oxide are added to the resin of the insulating layer 16, printing or coating suitability and aesthetic appearance can be improved. it can.
[00 19 ]
In the transparent touch panel of the present invention, the insulating layer 16 has a stripe or inner end portion as shown in FIG. 1 in a frame-like region that is adjacent to the inside of the adhesive layer between the upper electrode and the lower electrode . It has a feature of being formed in an intermittent comb-teeth shape (see FIG. 1).
[00 20 ]
In order to achieve the effect, it is preferable to set the ratio of the insulating layer 16 in the frame-shaped region to the portion without the insulating layer 16 in the range of 1:50 to 10: 1. In particular, the range of 3: 1 to 1: 5 is more preferable. preferable.
[00 21 ]
[Action]
Since the transparent touch panel of the present invention is configured as described above, the following effects are exhibited.
[00 22 ]
That is, even if the upper electrode conductive film is locally damaged by the inner upper corner of the insulating layer and the upper electrode conductive film is damaged, the upper electrode conductive film is only intermittently damaged.
[00 23 ]
Therefore, the conductive film of the upper electrode can maintain conductivity and uniformity even when sliding with a finger or pen near the position where the insulating layer is formed or in the vicinity thereof is repeated.
[00 24 ]
【Example】
Example 1
A lower electrode in which a pair of parallel bus bars made of a conductive film made of ITO and silver paste is formed on the upper surface of an insulating base material made of polyethylene terephthalate film, and a lower surface of a flexible insulating base material made of polycarbonate film A conductive film made of ITO and a pair of parallel bus bars made of silver paste are formed, and an upper electrode on which a hard coat layer containing ultrafine silica in urethane-based thermosetting resin is formed on the upper surface. A spacer made of urethane acrylate-based photo-curing resin is interposed between them so that the direction between the bus bars of the lower electrode and the direction of the bus bar of the upper electrode are orthogonal to each other, and the peripheral part is bonded with an adhesive layer made of double-sided tape. In the analog resistive film type transparent touch panel, a frame that is adjacent to the inside of the adhesive layer between the upper electrode and the lower electrode In the region, it provided with an insulating layer made of urethane-based thermosetting resin by a number of parallel stripes connecting the outside and inside of the frame-shaped region.
[00 25 ]
When the transparent touch panel thus configured was slid 10 times on or near the insulating layer with a polyacetal resin pen with a load of 4 kg and a radius of 0.8 mm, the linearity (linearity) was not impaired. For comparison, when a transparent touch panel in which a conventional insulating layer was substantially uniformly provided with a solid pattern was tested in the same manner at a load of 3 kg, linearity (linearity) was greatly impaired.
[00 26 ]
【The invention's effect】
Since the transparent touch panel of the present invention has the above configuration and operation, the following effects are exhibited.
[00 27 ]
That is, the conductive film of the upper electrode maintains its conductivity and uniformity even when sliding with a finger or a pen in the vicinity of the position where the insulating layer is formed or in the vicinity thereof, so that the linearity of the transparent touch panel is not impaired.
[Brief description of the drawings]
[Brief description of the drawings]
FIG. 1 is a plan view showing a transparent touch panel according to the present invention.
FIG. 2 is an exploded view showing a conventional transparent touch panel.
FIG. 3 is a principle diagram of a transparent touch panel.
FIG. 4 is a cross-sectional view showing a conventional transparent touch panel when the housing is housed.
FIG. 5 is a cross-sectional view showing a conventional transparent touch panel when the housing is housed.
FIG. 6 is a plan view showing a conventional transparent touch panel.
FIG. 7 is a partial enlarged view showing an input state of the transparent touch panel of FIG. 5;
FIG. 8 is a diagram showing linearity characteristics of a conventional transparent touch panel.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Insulation base material 2 Conductive film 3 Bus bar 4 Lower electrode 5 Flexible insulating base material 6 Conductive film 7 Bus bar 8 Upper electrode 9 Spacer 10 Adhesion layer 11 Route circuit 12 Divided voltage output terminal 13 Divided voltage output terminal 14 Window part 15 Window Frame 16 Insulating layer 17 Pen movement 18 Input content

Claims (1)

A lower electrode in which a transparent conductive film and a pair of parallel bus bars are formed on the upper surface of a transparent insulating base material, and an upper part in which a transparent conductive film and a pair of parallel bus bars are formed on the lower surface of the transparent flexible insulating base material In an analog resistance film type transparent touch panel in which a spacer is interposed between conductive films so that the direction between the bus bars of the lower electrode and the direction between the bus bars of the upper electrode are orthogonal to each other, and the peripheral part is bonded with an adhesive layer A transparent touch panel, wherein an insulating layer having an inner end formed in an intermittent comb shape is provided in a frame-like region that is adjacent to the inside of the adhesive layer between the upper electrode and the lower electrode.

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