JP6115196B2 - Touch panel sensor and input / output device - Google Patents

Description

  The present invention relates to a touch panel sensor including sensor electrodes formed in a predetermined pattern, and an input / output device including a touch panel sensor and a display device.

  Today, touch panel devices are widely used as input means. The touch panel device includes a touch panel sensor, a control circuit that detects a contact position on the touch panel sensor, wiring, and the like. In many cases, the touch panel device is used in combination with an output unit capable of displaying information, and functions as an input unit for the output unit. Examples of the output means include display devices such as a liquid crystal display and a plasma display, and examples of input / output devices that combine a touch panel device and a display device include ticket machines, ATM devices, mobile phones, and game machines. . In the input / output device, the touch panel sensor is disposed on the display surface of the display device, whereby the touch panel device enables extremely direct input to the display device. Therefore, the area | region which faces the display area of a display apparatus among touch panel sensors is transparent, and this area | region of a touch panel sensor comes to comprise the active area which can detect a contact position.

  The touch panel device can be classified into various types based on the principle of detecting the contact position with the touch panel sensor. In recent years, as represented by a projected capacitively coupled touch panel device, touch panel sensors including sensor electrodes formed in a predetermined pattern are widely used. Such a touch panel sensor is preferable in that a plurality of contact positions can be detected simultaneously.

JP 2012-071422 A

  By the way, since the patterned sensor electrode comes to be located in the active area, it is manufactured using a transparent conductor. However, the transparent conductor generally has a high refractive index as compared with other materials used for manufacturing a touch panel sensor. Therefore, the reflectance at each position of the touch panel sensor changes depending on the presence or absence of the sensor electrode, and as a result, the pattern of the sensor electrode is visually recognized. As a result of extensive studies by the present inventors, it has been confirmed that the occurrence of such a problem becomes more prominent when an antireflection layer is provided at a position that is the outermost surface of the touch panel sensor. When the sensor electrode pattern is detected on the display device, the display quality of the display device is significantly deteriorated.

  In Patent Document 1, the ratio of the refractive index of the patterned optical thin film and the refractive index of the layer adjacent to the optical thin film is set to a predetermined value, thereby preventing the optical thin film pattern from being visualized. Trying to. However, if the ratio of the refractive indices of two adjacent layers is limited, the range of materials that can be selected becomes narrow, which is not preferable.

  The present invention has been made in consideration of the above points, and an object of the present invention is to provide a touch panel sensor that can effectively make a sensor electrode pattern inconspicuous.

The touch panel sensor according to the present invention includes:
A touch panel sensor including sensor electrodes formed in a predetermined pattern,
A protective sheet body;
A sensor laminate including the sensor electrode;
An intermediate layer laminate provided between the protective sheet body and the sensor laminate,
The intermediate laminate includes a first layer disposed adjacent to the protective sheet body, and a second layer disposed adjacent to the first layer and positioned between the first layer and the sensor laminate. And having
The refractive index n ₁ of the first _layer, the refractive index n ₂ of the second _layer, and the refractive indices n _x of the portion adjacent to the first layer of said protective sheet member is,
n _x > n ₁ and n ₁ <n ₂ ... condition (a)
n _x <n ₁ and n ₁ > n ₂ ... condition (b)
Either one of the following conditions (a) or (b)
The thickness of the first layer is 30 nm or less.

  In the touch panel sensor according to the present invention, the thickness of the second layer may be 10 μm or more.

  In the touch panel sensor according to the present invention, the protective sheet body may include an antireflection layer.

An input / output device according to the present invention comprises:
Any of the touch panel sensors according to the invention described above;
A display device on which the touch panel sensor is stacked.

  According to the touch panel sensor of the present invention, the pattern of the sensor electrode can be effectively made inconspicuous.

FIG. 1 is a perspective view schematically illustrating an input / output device for explaining an embodiment of the present invention. FIG. 2 is a cross-sectional view showing the touch panel sensor in a cross section corresponding to the line II-II in FIG. FIG. 3 is a plan view showing a sensor laminate of the touch panel sensor. FIG. 4 is a cross-sectional view corresponding to FIG. 2 and showing a conventional touch panel sensor.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to the present specification, for the sake of illustration and ease of understanding, the scale, the vertical / horizontal dimension ratio, and the like are appropriately changed and exaggerated from those of the actual product.

  1 to 4 are diagrams for explaining an embodiment according to the present invention. 1 is a perspective view schematically showing an input / output device including a touch panel device and a display device, FIG. 2 is a diagram for explaining a layer structure of the touch panel sensor, and FIG. 3 is a touch panel. It is a figure for demonstrating an example of the pattern of the sensor electrode contained in a sensor.

  As shown in FIGS. 1 and 2, the input / output device 10 includes a display device 12 having a display surface 12 a and a touch panel device 20. The display device 12 can be composed of various known display devices such as a liquid crystal display device, a plasma display device, and an organic EL display device. The display device 12 includes a display area A1 that can display an image and a non-display area A2 that is disposed outside the display area A1 so as to surround the display area A1. The display device 12 displays a predetermined image on the display surface 12a according to a control signal from the display control unit 13. That is, the display device 12 plays a role as an output device that outputs information such as characters and drawings as an image.

  Next, the touch panel device 20 will be described. The touch panel device 20 includes a touch panel sensor 30 including sensor electrodes 61 and 62 formed in a predetermined pattern, and a detection control unit 21 electrically connected to the touch panel sensor 30. For example, the information detected by the detection control unit 21 is transmitted to the display control unit 13, and the display control unit 13 displays an image corresponding to the detection result of the detection control unit 21 on the display surface 12 a of the display device 12. . That is, the touch panel device 20 plays a role as an input device for inputting information.

  The touch panel sensor 30 is disposed at a position facing the display surface 12 a of the display device 12. The touch panel sensor 30 includes an active area Aa1 corresponding to an area where the touch position can be detected, and an inactive area Aa2 adjacent to the active area Aa1. The active area Aa1 of the touch panel sensor 30 occupies an area facing the display area A1 of the display device 12. On the other hand, the non-active area Aa2 is formed so as to surround the rectangular active area Aa1 from the four sides. The inactive area Aa2 is formed in a region facing the non-display region A2 of the display device 12.

  In the example described below, the touch panel device 20 is configured as a projected capacitively coupled touch panel device. When the detection sensitivity of the capacitively coupled touch panel device 20 is excellent, it is possible to detect which region of the touch panel device the external conductor is approaching just by approaching the external conductor to the touch panel device. . Along with such a phenomenon, the “contact position” used here is a concept including an approach position that is not actually in contact but can be detected.

  As shown in FIG. 2, the touch panel sensor 30 is positioned between the protective sheet 40 that forms the outermost surface, the sensor laminate 60 including the sensor electrodes 61 and 62, and the protective sheet 40 and the sensor laminate 60. Intermediate laminate 50. In the illustrated touch panel sensor 30, an adhesive layer 71 and a support base 72 are provided on the opposite side of the sensor laminate 60 from the intermediate laminate 50. Since each layer included in the touch panel sensor 30 is disposed on the display device 12, it is preferably transparent. In this specification, “adhesion” is used as a concept including adhesion.

The protective sheet body 40 forms not only the outermost surface of the touch panel sensor 30 but also the input surface of the input / output device 10. The touch panel device 20 is configured to detect contact with the protective sheet body 40. In the illustrated example, the protective sheet body 40 includes an antireflection layer 41, a protective material 42, and an adhesive layer 43 from the side opposite to the intermediate laminate 50. The antireflection layer 41 is formed, for example, as a layer having a refractive index lower than that of the protective material 42 and having a thickness of about 50 nm to 200 nm. The protective material 42 is a layer for protecting the sensor laminate 60 and the display device 12 and is formed as a layer having a thickness of about 100 μm to 1 mm using, for example, a resin such as glass, polyethylene terephthalate, or triacetyl cellulose. Can be done. The adhesive layer 43 is a layer for joining the protective sheet body 40 to the intermediate laminate 50. Refractive indices n _x of the adhesive layer 43, as will be described later, is set.

  The intermediate laminated body 50 has a first layer 51 disposed adjacent to the protective sheet body 40 and a second layer 52 disposed adjacent to the first layer 51. The first layer 51 is adjacent to the adhesive layer 43 of the protective sheet body 40. On the other hand, the second layer 52 is disposed between the first layer 51 and the sensor stack 60, and in particular, in the illustrated example, the second layer 52 of the intermediate stack 50 is connected to the sensor stack 60. Adjacent to each other.

As will be described later, the intermediate stacked body 50 adjusts the amount of reflection of light incident on the touch panel sensor 30, thereby observing the active area Aa 1 of the touch panel sensor 30 between the regions in the active area Aa 1. It is possible to suppress the occurrence of different colors. In other words, by adjusting the amount of reflection of light incident on the touch panel sensor 30 by the intermediate laminate 50, the color difference ΔE ^* corresponding to the presence or absence of the sensor electrodes 61 and 62 between the respective areas in the active area Aa1 is effective. Can be reduced.

However, providing the intermediate laminate 50 on the touch panel sensor 30 increases the number of interfaces of the touch panel sensor 30. Therefore, the light reflected by the touch panel sensor 30 among the light incident on the touch panel sensor 30 increases. However, when the display surface 12a is observed brightly due to the reflected light, the contrast of the image displayed by the display device 12 is lowered. To avoid such an inconvenience, the refractive index n ₁ of the first layer _51, the refractive index n ₂ of the second layer _52, and the refractive index of the part adjacent to the first layer 51 of the protective sheet member 40 n _x, the refractive indices n _x of the adhesive layer 43 in the example illustrated is,
n _x > n ₁ and n ₁ <n ₂ ... condition (a)
n _x <n ₁ and n ₁ > n ₂ ... condition (b)
One of the following conditions (a) and (b) is satisfied, and the thickness t of the first layer 51 is set to 30 nm or less.

In addition, the refractive index of each layer and each part uses Abbe refractometer (NAGO-4T made by Atago Co., Ltd.), "Ellipsometer M150" made by JASCO Corporation, "KOBRA-WR" made by Oji Scientific Instruments, etc. Can be measured. The refractive index _n 1 to be _measured, n 2, _{n x} is the average in-plane refractive index. Then, a layer of interest, if the site is optically isotropic, it is also possible to measure the refractive index n _1, n _2, n _x as follows. First, the cured film of each layer is scraped off with a cutter or the like to produce a powder sample. Next, the Becke method according to JISK7142 (2008) B method (for powder or granular transparent material) can be used. Here, the Becke method uses a Cargill reagent having a known refractive index, places the powdered sample on a slide glass or the like, drops the reagent on the sample, and immerses the sample in the reagent. This is observed by using a microscope, and this is a method in which the refractive index of the sample is the refractive index of the reagent in which the bright line generated in the sample outline due to the difference in refractive index between the sample and the reagent;

  When the condition (a) or the condition (b) is satisfied and the thickness t of the first layer 51 is 30 nm or less, reflection at the interface between the adhesive layer 43 and the first layer 51 and the first layer 51 are performed. However, it is possible to effectively reduce the intensity of the reflected light, that is, effectively prevent the reflected light from being viewed brightly.

  When one of the condition (a) and the condition (b) is satisfied, the light incident on the touch panel sensor 30 from the protective sheet body 40 side is the interface between the adhesive layer 43 and the first layer 51 and the first layer 51 and the first layer 51. Free end reflection is performed at one of the interfaces with the two layers 52, and fixed end reflection is performed at the other interface. That is, when one of the condition (a) and the condition (b) is satisfied, reflection is performed at one of the interface between the adhesive layer 43 and the first layer 51 and the interface between the first layer 51 and the second layer 52. The reflected light is reflected at the free end to maintain the phase, but the light reflected at the other interface is reflected at the fixed end to shift the phase by π [rad].

  Accordingly, when the thickness t of the first layer 51 is sufficiently small with respect to the wavelength, the light reflected at the interface between the adhesive layer 43 and the first layer 51, the first layer 51, and the second layer The light reflected at the interface with 52 cancels each other. That is, the combined reflected light of the reflected light at the interface between the adhesive layer 43 and the first layer 51 and the reflected light at the interface between the first layer 51 and the second layer 52 has a reduced intensity and is brightly observed. Disappear. Typically, when the thickness t of the first layer 51 is in the vicinity of 0 nm, the combined reflected light is the darkest. Then, as the thickness t of the first layer 51 is increased within a predetermined range, for example, in a range greater than 0 and equal to or less than 60 nm, the combined reflected light becomes brighter.

  As a result of extensive research conducted by the present inventor, when one of the conditions (a) and (b) is satisfied and the thickness t of the first layer 51 is set to 30 nm or less, the intermediate laminate 50 is attached to the touch panel sensor 30. It was possible to effectively prevent a decrease in contrast due to the addition to the above. When one of the condition (a) and the condition (b) is satisfied and the thickness t of the first layer 51 is set to 15 nm or less, the case where the intermediate laminate 50 is provided on the touch panel sensor 30 and the case where the intermediate laminate 50 is The difference in brightness due to reflected light from the case where the touch panel sensor 30 is not provided cannot be grasped by visual observation.

The first layer 51 and the second layer 52 can be manufactured as follows. For example, in order to satisfy the above-described condition (a), the first layer 51 is formed by forming a low refractive index layer made of MgF ₂ and having a thickness of about 10 nm by vapor deposition or ion plating. In addition, a high refractive index layer made of an acrylic resin and having a thickness of about 20 μm can be formed by coating to form the second layer 52. Further, in order to satisfy the above-mentioned condition (b), a high refractive index layer made of niobium oxide Nb ₂ O ₅ and having a thickness of about 5 nm can be formed by sputtering to form the first layer 51, and The second layer 52 can be formed by coating a low refractive index layer made of acrylic resin and having a thickness of about 20 μm.

  Note that the thickness of the second layer 52 does not strongly affect the intensity of the combined reflected light resulting from the provision of the intermediate laminate 50. However, from the viewpoint of effectively preventing interference between the reflected light at the interface between the first layer 51 and the second layer 52 and the reflected light at the interface between the second layer 52 and the sensor stack 60, the first The thickness of the two layers 52 is preferably 10 μm or more. As a result of extensive research conducted by the present inventors, when the thickness of the second layer 52 is 10 μm or more, the problematic interference does not stand out, thereby avoiding a change in color caused by the interference. I was able to.

  Since the thickness of the first layer 51 is set to be thin, the transmittance is not significantly reduced by being greatly affected by the extinction coefficient k. On the other hand, since the thickness of the second layer 52 is set to be relatively thick, the second layer 52 is preferably formed using a material having a small extinction coefficient k. In this respect, it is preferable to form the second layer 52 from an acrylic resin transparent to the visible light region, coated glass, or the like.

  Next, the sensor laminate 60 will be described. The sensor laminate 60 includes a sensor base 65, a first sensor electrode 61 provided on a surface of the sensor base 65 on the intermediate laminate 50 side, and a side opposite to the intermediate laminate 50 of the sensor base 65. And a second sensor electrode 62 provided on the surface. The sensor base 65 can be formed as a layer having a thickness of about 20 μm to 1 mm using, for example, a resin such as glass, polyethylene terephthalate, or cycloolefin polymer.

  The first sensor electrode 61 is formed by a plurality of transparent conductors arranged in a stripe pattern on one surface of the sensor substrate 65. The first sensor electrode 61 is mainly formed in the active area Aa1. On the other hand, in the non-active area Aa2 on one surface of the sensor base 65, a first extraction wiring 61a is provided. The first extraction wiring 61a includes a plurality of conductors. Each conductor extends from each transparent conductor constituting the first sensor electrode 61. Each conductor constituting the first extraction wiring 61 a extends to the edge of one surface of the sensor base 65 and is connected to the display control unit 13.

  The second sensor electrode 62 is formed of a plurality of transparent conductors arranged in a stripe pattern on the other surface of the sensor substrate 65. The transparent conductor that forms the second sensor electrode 62 may have the same configuration except that the longitudinal direction of the transparent conductor that forms the first sensor electrode 61 intersects, in particular, perpendicularly. On the other surface of the sensor base 65, a second extraction wiring 62a is provided. The second extraction wiring 62a includes a plurality of conductors. The conductor forming the second extraction wiring 62a may have the same configuration as the conductor forming the first extraction wiring 61a.

  In the illustrated example, each transparent conductive material that forms the first sensor electrode 61 and the second sensor electrode 62 so that a wider area of the active area Aa1 is covered with the first sensor electrode 61 or the second sensor electrode 62. The body has a widened bulge. Specifically, each of the transparent conductors forming the first sensor electrode 61 has a square-shaped bulging portion in plan view between the two intersecting adjacent transparent conductors forming the second sensor electrode 62. Have. Similarly, each of the transparent conductors forming the second sensor electrode 62 has a square-shaped bulge in a plan view between the portions intersecting with two adjacent transparent conductors forming the first sensor electrode 61. ing.

  As the material of the sensor electrodes 61 and 62, a material having transparency and required conductivity is used. Examples of such materials include indium tin oxide (ITO), zinc oxide, indium oxide, antimony-added tin oxide, fluorine-added tin oxide, aluminum-added zinc oxide, potassium-added zinc oxide, silicon-added zinc oxide, and zinc oxide-oxide Examples thereof include metal oxides such as tin-based, indium oxide-tin oxide-based, and zinc oxide-indium oxide-magnesium oxide-based, and two or more of these metal oxides may be combined. The formation method of the sensor electrodes 61 and 62 is not particularly limited, and a sputtering method, a vacuum deposition method, an ion plating method, a CVD method, a coating method, a printing method, or the like can be used. On the other hand, the extraction wirings 61 a and 62 a can be manufactured using the same material as the sensor electrodes 61 and 62 and using the same method as the sensor electrodes 61 and 62. However, since it is provided in the non-active area Aa2, it may be produced by a coating method such as screen printing using a non-transparent material such as silver paste.

  By the way, in the touch panel sensor 30 including the sensor stack 60 shown in FIGS. 2 and 3, the active area Aa1 includes the first region Z1 in which both the first sensor electrode 61 and the second sensor electrode 62 exist, the first A second region Z2 in which the first sensor electrode 61 exists and the second sensor electrode 62 does not exist; a third region Z3 in which the first sensor electrode 61 does not exist and the second sensor electrode 62 exists; and the first sensor electrode 61 and the second sensor electrode 62 are divided into the fourth region Z4. In the conventional touch panel sensor, the way in which the reflected light from the first region is observed is different from the way in which the reflected light from the second region Z2 or the third region Z3 is sensed. The pattern of the sensor electrodes 61 and 62 is visually recognized due to the difference between the way the reflected light from the four regions Z4 is observed and the way the reflected light from the second region Z2 or the third region Z3 is observed. There was a case. When the patterns of the sensor electrodes 61 and 62 are visually recognized, the display quality of the display device 12 is significantly deteriorated. And as demonstrated also in the following experimental examples, such a problem becomes more prominent when an antireflection layer is provided on the outermost surface of the touch panel sensor 30.

Although details of the reason why the defect becomes conspicuous by providing the antireflection layer is unknown, the a ^* b ^* plane expands as the reflectivity decreases (≈L ^* decreases). It is inferred that one of the factors is that color differences are easily identified as the brightness of light decreases.

On the other hand, according to the touch panel sensor 30 described above, the intermediate laminate 50 is provided as described above. Then, the refractive index n ₁ of the first layer _51, the refractive index n ₂ of the second layer _52, and the refractive indices n _x a portion adjacent to the first layer 51 of the protective sheet _40, in the example shown is refractive indices _{n x} of the adhesive layer 43,
n _x > n ₁ and n ₁ <n ₂ ... condition (a)
n _x <n ₁ and n ₁ > n ₂ ... condition (b)
One of the following conditions (a) and (b) is satisfied, and the thickness t of the first layer 51 is set to 30 nm or less. As a result of extensive research conducted by the present inventors, according to the touch panel sensor 30 including such an intermediate laminated body 50, the pattern of the sensor electrodes 61 and 62 is effectively made inconspicuous, and further made invisible. I was able to.

  Although the detailed mechanism by which the pattern of the sensor electrodes 61 and 62 can be effectively inconspicuous by the intermediate laminate 50 is not clear, it is assumed that the following is one factor. However, the present invention is not limited to the following inference.

  That is, by providing the intermediate laminate 50, at least a part of the light that enters the touch panel sensor 30 and travels toward the sensor laminate 60 is reflected by the intermediate laminate 50. However, as long as the condition (a) or the condition (b) is satisfied and the thickness t of the first layer 51 is reduced to 30 nm or less, both the incident side and the outgoing side of the first layer 51 have interfaces. The reflected lights will cancel each other out. For this reason, the intensity | strength of synthetic | combination reflected light falls and this synthetic | combination reflected light is not observed too brightly. And by adjusting the intensity | strength of synthetic | combination reflected light with the film thickness of the 1st layer 51, as a result, reflected light is not conspicuous and a color difference can be suppressed.

Specifically, in the light reflected from the first to fourth regions Z1-Z4, although there is ^a possibility ^{that L *} is increased at a defined ^L * ^a * ^{b *} color system in JISZ8729, to be contrasted The difference “Δa ^* ” and “Δb ^* ” between “a ^* ” and “b ^* ” between regions can be reduced. Intuitively, color differences are less likely to be identified as the brightness increases. As a result, the difference "[Delta] L ^*" in the "L ^*" in the area to be contrasted, "a ^*" difference ".DELTA.a ^*", and "b ^*" difference "[Delta] b ^*", respectively squaring in addition the value the color difference Delta] E * represented by the square root ^of, that is, to reduce the color difference Delta] E ^* which is expressed by the following equation (1).
ΔE ^* = ((ΔL ^* ) ² + (Δa ^* ) ² + (Δb ^* ) ² ) ^1/2 ... Formula (1)

  Here, an example of the experimental results actually performed by the inventors will be described.

  First, a touch panel sensor having the configuration described with reference to FIGS. A touch panel sensor different from sample 1 only in that the antireflection layer was omitted was prepared as sample 2. A touch panel sensor different from Sample 1 only in that the intermediate laminate was omitted was prepared as Sample 3 for comparison. A touch panel sensor different from Sample 2 only in that the intermediate laminate was omitted was prepared as Sample 4 for comparison. Between each sample, a common layer was manufactured using the same material and having the same structure. Sample 3 has the same configuration as the touch panel sensor actually incorporated in a commercially available smartphone.

Specifically, each layer of each sample was configured as follows.
○ Protective sheet 40
-Antireflection layer 41
And a layer thickness of 100nm composed of MgF ₂ formed by vapor deposition.
・ Protective material 42
A 1 mm thick film made of polycarbonate was used.
・ Adhesive layer 43
A layer made of acrylic resin and having a thickness of 50 μm was used. Refractive indices _{n x} was 1.46. The value 1.46 of the refractive indices _{n x} is a value of wavelength 589nm to light.
○ Intermediate laminate 50
・ First layer 51
A 5 nm thick layer of niobium oxide Nb ₂ O ₅ formed by sputtering was used. The refractive index n ₁ was 2.20 for light with a wavelength of 589 nm.
・ Second layer 52
It was set as the 25-micrometer-thick layer which consists of acrylic resin formed by coating. The refractive index n ₁ was 1.51 for light with a wavelength of 589 nm.
○ Sensor stack 60
Sensor substrate 65
A film made of polyethylene terephthalate and having a thickness of 100 μm was used.
First sensor electrode 61 and second sensor electrode 62
It was formed from indium tin oxide (ITO) by sputtering. The thickness was 20 nm and the refractive index was 1.80 for light with a wavelength of 589 nm.
○ Adhesive layer 71
A layer made of acrylic resin and having a thickness of 50 μm was used.
○ Support base 72
A 1 mm thick film made of polyethylene terephthalate was used.

Regarding the reflected light from the first to fourth regions Z1 to Z4 of each sample, “L ^* ”, “a ^* ” and “b ^* ” in the L ^* a ^* b ^* color system were measured. The measurement was performed according to JISZ8729, and a D65 light source was used. Further, [Delta] L ^* a fourth region Z4 is the difference in ^{L *} between the first region Z1, ^{a *} is the difference .DELTA.a ^*, and, [Delta] b ^* was calculated as the difference of ^{b *.} Similarly, [Delta] L ^* between the fourth region Z4 and the second region Z2, the .DELTA.a ^* and Δb ^{*, ΔL *} between the fourth region Z4 and the third region Z3, and .DELTA.a ^* and [Delta] b ^*, a Asked. Furthermore, based on Equation (1) described above, the color difference between the fourth region Z4 and the first region Z1 Delta] E ^* color difference between the fourth region Z4 and the second region Z2 Delta] E ^*, and fourth The color difference ΔE ^* between the region Z4 and the third region Z3 was determined. The results for Sample 1 are shown in Table 1, the results for Sample 2 are shown in Table 2, the results for Sample 3 are shown in Table 3, and the results for Sample 4 are shown in Table 4.

The color difference between Sample 1 and Sample 2 provided with the intermediate laminate 50 was much smaller than the color difference between Sample 3 and Sample 4 where the intermediate laminate 50 was not provided. Actually, when the sensor electrodes 61 and 62 of each sample were observed with the naked eye, almost no pattern of the sensor electrodes 61 and 62 could be found in the samples 1 and 2. On the other hand, in the sample 3 and the sample 4, when carefully observed, the patterns of the sensor electrodes 61 and 62 were visually recognized. Further, when the antireflection layer 41 is provided on the outermost surface of the touch panel sensor 30, the color difference ΔE ^* is increased.

  Samples 1 to 4 were placed on the display surface of a commercially available television receiver, and the display quality of the television receiver was confirmed. There was no difference in display quality between samples 1-4.

According to the present embodiment as described above, the refractive index n ₁ of the first layer _51, the refractive index n ₂ of the second layer _52, and, the portion adjacent to the first layer 51 of the protective sheet 40 Refractive index _nx is
n _x > n ₁ and n ₁ <n ₂ ... condition (a)
n _x <n ₁ and n ₁ > n ₂ ... condition (b)
One of the following conditions (a) and (b) is satisfied, and the thickness t of the first layer 51 is set to 30 nm or less. As a result, the pattern of the sensor electrodes 61 and 62 can be effectively made inconspicuous.

  Note that various modifications can be made to the above-described embodiment. For example, instead of the antireflection layer 41, an antiglare layer having an antiglare function may be provided. Moreover, you may make it provide various functions, such as an antistatic function, in any layer.

DESCRIPTION OF SYMBOLS 10 Input / output device 12 Display device 13 Display control unit 20 Touch panel device 21 Detection control unit 30 Touch panel sensor 40 Protective sheet body 41 Antireflection layer 42 Protective material 43 Adhesive layer 50 Intermediate layer 51 First layer 52 Second layer 60 Sensor laminated body 61 First sensor electrode 62 Second sensor electrode 65 Sensor base material 71 Adhesive layer 72 Support base material A1 Display area A2 Non-display area Aa1 Active area Aa2 Inactive area

Claims (3)

A touch panel sensor including sensor electrodes formed in a predetermined pattern,
A protective sheet body;
A sensor laminate including the sensor electrode;
An intermediate laminate provided between the protective sheet body and the sensor laminate,
The intermediate laminate includes a first layer disposed adjacent to the protective sheet body, and a second layer disposed adjacent to the first layer and positioned between the first layer and the sensor laminate. And having
The refractive index n ₁ of the first _layer, the refractive index n ₂ of the second _layer, and the refractive indices n _x of the portion adjacent to the first layer of said protective sheet member is,
n _x > n ₁ and n ₁ <n ₂ ... condition (a)
n _x <n ₁ and n ₁ > n ₂ ... condition (b)
Either one of the following conditions (a) or (b)
The thickness of the first layer state, and are less 30 nm,
The touch panel sensor , wherein the second layer has a thickness of 10 μm or more . The touch panel sensor according to claim 1 , wherein the protective sheet body includes an antireflection layer. A touch panel sensor including sensor electrodes formed in a predetermined pattern;
A display device laminated with the touch panel sensor,
The touch panel sensor has a protective sheet body, a sensor laminated body including the sensor electrode, and an intermediate laminated body provided between the protective sheet body and the sensor laminated body,
The intermediate laminate includes a first layer disposed adjacent to the protective sheet body, and a second layer disposed adjacent to the first layer and positioned between the first layer and the sensor laminate. And having
The refractive index n ₁ of the first _layer, the refractive index n ₂ of the second _layer, and the refractive indices n _x of the portion adjacent to the first layer of said protective sheet member is,
n _x > n ₁ and n ₁ <n ₂ ... condition (a)
n _x <n ₁ and n ₁ > n ₂ ... condition (b)
Either one of the following conditions (a) or (b)
The thickness of the first layer state, and are less 30 nm,
The input / output device , wherein the second layer has a thickness of 10 µm or more .

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