JP2015194799A - Substrate for touch panel sensor and touch panel sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate for a touch panel sensor being inexpensive and having an invisibility layer with excellent chemical resistance.SOLUTION: A substrate for a touch panel sensor includes: a glass substrate; and an invisibility layer formed on one surface of the glass substrate and including a laminate of a plurality of resin layers having different refractive indices and containing a transparent resin. In the invisibility layer, the top layer of the laminate includes a thermosetting resin.

Description

  The present invention relates to a touch panel sensor substrate that can suitably suppress the appearance of a transparent electrode layer when a touch panel sensor is used, and a touch panel sensor using the same.

  Today, touch panels are widely used as input means. In many cases, a touch panel is used together with a display device as an input means for various devices in which a display device such as a liquid crystal display or a plasma display is incorporated (for example, a ticket vending machine, an ATM device, a mobile phone, a game machine). Yes. In such a device, the touch panel is placed on the display surface of the display device, which allows the touch panel to make a very direct input to the display device.

  Various types of touch panels have been put into practical use. Among these, what is called a capacitance system has a sensor electrode having, for example, a first electrode and a second electrode insulated from the first electrode. Then, a weak current is passed through the touch panel surface of the touch panel to form an electric field, and the change in capacitance value when a finger or other conductor is lightly touched is converted into a voltage drop or the like and detected. The obtained contact position is output as a signal.

Since the touch panel sensor described above is used together with a display device, it is usually required to have transparency. As the sensor electrode described above, an inorganic transparent conductive material such as ITO is used, for example. Further, the first electrode and the second electrode of the sensor electrode are usually formed in a predetermined pattern shape on the transparent substrate.
In this case, in the touch panel sensor, a region in which the transparent electrode layer is formed (hereinafter sometimes referred to as a pattern formation region) and a region in which the transparent electrode layer is not formed (hereinafter, non-pattern formation). The pattern shape of the transparent electrode layer is observed by the touch panel operator because the optical characteristics such as light reflectance, transmittance, and color of transmitted light are different from each other. There is a problem that bone appearance of the transparent electrode layer occurs.

  For this problem, for example, it has been proposed to form an index matching layer (invisible layer) composed of a laminate of a high refractive index layer and a low refractive index layer on the entire surface of the transparent substrate ( Patent Document 1). The invisible layer is a functional layer that suppresses the bone appearance of the transparent electrode layer described above by adjusting the difference in optical characteristics between the pattern forming region and the non-pattern forming region described above.

As the invisible layer, for example, a layer formed by laminating a plurality of layers of inorganic materials such as Nb ₂ O ₅ , SiN, SiON, and SiO ₂ having different refractive indexes is preferably used. Such an inorganic material can be formed as a thin film, and can appropriately suppress the above-described bone appearance. However, when an invisible layer is formed using an inorganic material, for example, special equipment such as a vacuum deposition method or a sputtering method is required, and there is a problem that the method for forming the invisible layer becomes complicated. Therefore, there exists a problem that the manufacturing cost of a touch panel sensor becomes high.

Therefore, in recent years, a method for forming an invisible layer using an organic material has been studied. Such an invisible layer is formed using, for example, a resin material whose refractive index is adjusted. In the touch panel sensor, conventionally, a resin film has been suitably used as a substrate from the viewpoint of workability. As the invisible layer, a photocurable resin is suitably used from the viewpoint of the heat resistance of the resin film.
Here, since the invisible layer has a problem that rainbow unevenness is observed due to the influence of light interference when the thickness is thick, the thickness is required to be formed on the nano order. . However, when a thin film is formed using a photocurable resin, when the curing process is performed by exposure in an air atmosphere, the photocuring reaction may not sufficiently proceed due to oxygen inhibition on the surface of the film. Such an invisible layer becomes insufficient in chemical resistance against an acidic solution for etching and an alkaline solution for resist removal used for forming a transparent electrode layer by a photolithography method, and the invisible layer is deteriorated. In addition, there is a problem that the invisible layer itself may be peeled off from the transparent substrate.

  In order to suppress the above-described oxygen inhibition, for example, it is considered to expose a film containing a photocurable resin under a nitrogen atmosphere to form an invisible layer having good hardness and good chemical resistance. However, in this case, there is a problem that special equipment for performing exposure in a nitrogen atmosphere is required, resulting in an increase in manufacturing cost.

JP 2012-146217 A

  The present invention has been made in view of the above circumstances, and has as its main object to provide an inexpensive touch panel sensor substrate having an invisible layer with good chemical resistance and a touch panel sensor using the same.

  In order to achieve the above object, the present invention provides a glass substrate and an invisibility formed of a laminate of a plurality of resin layers formed on one surface of the glass substrate and including a transparent resin and having different refractive indexes. And the invisible layer provides a substrate for a touch panel sensor, wherein the uppermost layer of the laminate is a layer containing a thermosetting resin.

  According to the present invention, the invisible layer is an inexpensive touch sensor substrate having an invisible layer with good chemical resistance, because the uppermost layer of the laminate is a layer containing a thermosetting resin. be able to.

  In the above invention, it is preferable that the uppermost layer is a low refractive index layer and the resin layer in contact with the uppermost layer is a high refractive index layer. It is because it can be set as the board | substrate for touch panel sensors which can suppress suitably the bone | frame appearance of a transparent electrode layer when it is set as a touch panel sensor.

  In the said invention, the layer containing the photocurable resin may be sufficient as the said resin layer formed in the lower layer of the said uppermost layer. This is because it is easy to adjust the optical characteristics of the invisible layer using a general-purpose photocurable resin having an adjusted refractive index, and the material selectivity of the invisible layer can be widened.

  In the said invention, the layer containing a thermosetting resin may be sufficient as the said resin layer formed in the lower layer of the said uppermost layer. This is because the chemical resistance of the invisible layer can be improved.

  In the said invention, it is preferable that the said uppermost layer does not contain the particle | grains for adjusting a refractive index. This is because the chemical resistance of the invisible layer can be improved.

  In the said invention, it is preferable that the thickness of the said uppermost layer is 200 nm or less. This is because when the thickness of the uppermost layer is equal to or less than the above value, it is possible to obtain the uppermost layer having higher curability than in the case where the uppermost layer includes a photocurable resin.

  The present invention includes a glass substrate, an invisible layer formed on the glass substrate, including a transparent resin and composed of a laminate of a plurality of resin layers having different refractive indexes, and a pattern on the invisible layer. And a transparent electrode layer containing an inorganic conductive material, wherein the invisible layer is a layer containing a thermosetting resin as a top layer of the laminate. To do.

  According to this invention, it can be set as the cheap touch panel sensor with little deterioration of an invisible layer by having an invisible layer which has the said structure.

  In this invention, there exists an effect that it can be set as the cheap board | substrate for touchscreen sensors which has an invisible layer with favorable chemical resistance.

It is a schematic sectional drawing which shows an example of the board | substrate for touchscreen sensors of this invention. It is a schematic sectional drawing which shows the other example of the board | substrate for touchscreen sensors of this invention. It is the schematic plan view and schematic sectional drawing which show an example of the touchscreen sensor of this invention. It is the schematic plan view and schematic sectional drawing which show the other example of the touchscreen sensor of this invention. It is the schematic plan view and schematic sectional drawing which show the other example of the touchscreen sensor of this invention.

  Hereinafter, the substrate for a touch panel sensor and the touch panel sensor of the present invention will be described.

A. Touch Panel Sensor Substrate The touch panel sensor substrate according to the present invention is formed on a glass substrate and one surface of the glass substrate, includes a transparent resin, and includes a laminate of a plurality of resin layers having different refractive indexes. The invisible layer is characterized in that the uppermost layer of the laminate is a layer containing a thermosetting resin.

The touch panel sensor substrate of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic sectional view showing an example of a touch panel sensor substrate of the present invention. As shown in FIG. 1, a touch panel sensor substrate 1 of the present invention is formed on a glass substrate 2 and one surface of the glass substrate 2, a transparent resin containing a plurality of resin layers having different refractive indexes. And an invisible layer 3 composed of a body. The invisible layer 3 is characterized in that the uppermost layer of the laminate is a layer containing a thermosetting resin. In FIG. 1, the invisible layer 3 is a laminate of two resin layers, a high refractive index layer 31 formed on the glass substrate 2 and a low refractive index layer 32 formed on the high refractive index layer 31. It shows an example in which the uppermost layer is a low refractive index layer 32.

FIG. 2 is a schematic sectional view showing another example of the touch panel sensor substrate of the present invention.
In the present invention, the invisible layer 3 only needs to be formed on at least one surface of the glass substrate 2, and may be formed only on one surface of the glass substrate 2 as shown in FIG. As shown in FIG. 2, it may be formed on both surfaces of the glass substrate 2. Note that the reference numerals not described in FIG. 2 are the same as the contents described in FIG. 1 described above, and thus the description thereof is omitted here.

  According to the present invention, the invisible layer is an inexpensive touch sensor substrate having an invisible layer with good chemical resistance, because the uppermost layer of the laminate is a layer containing a thermosetting resin. be able to.

More specifically, according to the present invention, since the uppermost layer of the invisible layer is a layer containing a thermosetting resin, the forming step of the invisible layer contains a thermosetting resin. The uppermost layer-forming composition can be applied onto another resin layer of the invisible layer to form a coating film, and the coating film can be sufficiently cured by heat treatment to form the uppermost layer. Therefore, when the transparent electrode layer of the touch panel sensor is formed using a photolithography method because the uppermost layer of the invisible layer is sufficiently cured, the acidic solution used for etching the transparent electrode layer, the transparent electrode layer Deterioration of the uppermost layer due to the alkaline solution used for stripping the resist used for patterning can be suppressed.
Further, according to the present invention, since the uppermost layer of the invisible layer is a layer containing a thermosetting resin, in the step of forming the invisible layer, the above-described heat treatment of the coating film in an air atmosphere Since the uppermost layer can be formed by performing the above, no special equipment is required, and the invisible layer can be formed by a simple method. Therefore, the manufacturing cost of the touch panel sensor substrate can be reduced, and the cost can be reduced.

  Details of the touch panel sensor substrate of the present invention will be described below.

1. Invisible layer The invisible layer in the present invention is a layer formed on one surface of the glass substrate and composed of a laminate of a plurality of resin layers containing a transparent resin and having different refractive indexes. In the present invention, the uppermost layer of the laminate is a layer containing a thermosetting resin.

  The invisible layer suppresses the above-mentioned bone appearance of the transparent electrode layer by combining the optical characteristics of the pattern formation region and the non-pattern formation region in the touch panel sensor having the transparent electrode layer formed in a predetermined pattern. It is a layer formed for the purpose.

The invisible layer usually has at least one low refractive index layer and at least one high refractive index layer. The number of low refractive index layers, the number of high refractive index layers, and the low refractive index The order of stacking the layers and the high refractive index layer can be appropriately selected according to the inorganic conductive material used for the transparent electrode layer of the touch panel sensor, the thickness, and the like.
As the invisible layer in the present invention, the uppermost layer is preferably a low refractive index layer, and the resin layer in contact with the uppermost layer is preferably a high refractive index layer. This is because the bone appearance of the transparent electrode layer can be satisfactorily suppressed. The invisible layer in the present invention is a laminate of two resin layers having a high refractive index layer formed on a glass substrate and a low refractive index layer formed on the high refractive index layer. It is particularly preferred. This is because since the invisible layer can be configured with a small number of layers, the manufacturing process of the touch panel sensor substrate can be simplified, and the manufacturing cost can be reduced and the manufacturing cost can be reduced.

Here, the “low refractive index layer” in the present invention refers to a resin layer having a refractive index in the range of 1.40 or more and less than 1.65.
The “high refractive index layer” in the present invention refers to a resin layer having a refractive index in the range of 1.65 or more and 2.00 or less.

The refractive indexes of the low refractive index layer and the high refractive index layer described above are values calculated by measuring the resin layer using an ellipsometer at a wavelength of 550 nm.
Hereinafter, the configuration of the invisible layer will be described.

(1) Uppermost layer The uppermost layer of the invisible layer in the present invention is a layer located on the outermost surface on the side opposite to the glass substrate side of the substrate for touch panel among the laminate of a plurality of resin layers constituting the invisible layer. It is. The uppermost layer is a layer containing a thermosetting resin.

As the thermosetting resin, any resin may be used as long as it contains a component that is cured by heating to cause a polymerization reaction. For example, polymethyl methacrylate resin, polyacrylate resin, polycarbonate resin, polyvinyl alcohol resin, polyvinyl pyrrolidone resin, Examples thereof include hydroxyethyl cellulose resin, carboxymethyl cellulose resin, polyvinyl chloride resin, melamine resin, phenol resin, alkyd resin, epoxy resin, polyurethane resin, polyester resin, maleic acid resin, polyamide resin and the like.
Moreover, as said thermosetting resin, it is more preferable that it is a thing with higher chemical resistance at the time of hardening and setting it as a resin layer, and a thing with high alkali resistance is especially preferable. This is because when the transparent electrode layer is formed on the touch panel sensor substrate by using a photolithography method, the invisible layer is easily deteriorated by the alkaline solution used when the resist is peeled off.

  The uppermost layer may further contain a low molecular compound such as a carboxylic acid anhydride as an initiation aid for facilitating the initiation of the polymerization reaction. The content ratio of the initiation assistant composed of the low molecular weight compound can be appropriately selected according to the content ratio of the thermosetting resin, the formation condition of the uppermost layer, and the like. As the ratio of the above-mentioned starting aid, it is in the range of 0.5 to 15 parts by mass, particularly 1 to 10 parts by mass per 100 parts by mass of the solid content of the composition for forming the uppermost layer for forming the uppermost layer. It is preferably within the range of parts.

  The uppermost layer is not particularly limited as long as it contains the above-described thermosetting resin. For example, particles for adjusting the refractive index (hereinafter may be referred to as “refractive index adjusting particles”). It may be included, and the refractive index adjusting particles may not be included. In the present invention, it is more preferable that the uppermost layer contains no refractive index adjusting particles. This is because when the uppermost layer includes refractive index adjusting particles, the refractive index adjusting particles are exposed on the surface of the uppermost layer, and the chemical resistance of the surface of the uppermost layer may be lowered. The refractive index adjusting particles may be contained as long as the chemical resistance of the surface of the uppermost layer is not affected. The refractive index adjusting particles will be described later.

The thickness of the uppermost layer is not particularly limited as long as the invisible layer can be formed, but is preferably 200 nm or less from the viewpoint of the invisible effect, and particularly within the range of 5 nm to 100 nm, particularly 10 nm to 50 nm. It is preferable to be within the range.
When forming a layer using a photo-curing resin, if the thickness is less than the above-mentioned value, the curing reaction of the resin layer is less likely to proceed due to oxygen inhibition when exposure is performed in an air atmosphere. Cheap. Therefore, when the thickness of the uppermost layer is not more than the above value, the effects of the present invention can be suitably exhibited.
Moreover, if the thickness of the uppermost layer is large, the thickness of the invisible layer is increased, and for example, rainbow unevenness due to light interference may be observed.
The lower limit of the thickness of the uppermost layer is not particularly limited as long as the optical characteristics of the uppermost layer can be adjusted to a predetermined value, but is about 5 nm, for example, from the viewpoint of film formation.

  The thickness of the uppermost layer, the other resin layers described later, and the entire invisible layer in the present invention can be measured by a general measurement method. As a method of measuring the thickness, for example, a method of measuring using an observation image of a transmission electron microscope (TEM), a stylus type method of calculating the thickness by tracing the surface with a stylus and detecting irregularities, And an optical method for calculating the thickness based on the spectral reflection spectrum. Specifically, the thickness can be measured using a stylus type film thickness meter P-15 manufactured by KLA-Tencor Corporation. In addition, the average value of the thickness measurement result in several places of the member used as object may be used as thickness.

(2) Other resin layer The other resin layer of the invisible layer in this invention is a resin layer formed in the lower layer of the uppermost layer.
In the present invention, if the uppermost layer includes a thermosetting resin, the outermost surface of the invisible layer can be sufficiently cured, so that chemical resistance can be imparted to the invisible layer. Therefore, the resin layer formed in the lower layer of the uppermost layer may be a layer containing a photocurable resin or a layer containing a thermosetting resin. When the other resin layer is a layer containing a photocurable resin, it is easy to adjust the optical characteristics of the invisible layer using a general-purpose photocurable resin having an adjusted refractive index. The material selectivity can be widened. On the other hand, when the other resin layer is a layer containing a thermosetting resin, the chemical resistance of the invisible layer can be improved.

  The thermosetting resin used for the other resin layers can be the same as the contents described in the above-mentioned section “(1) Top layer”, and thus the description thereof is omitted here.

As a photocurable resin used for said other resin layer, what is used for a general touch panel sensor can be used. The photocurable resin is preferably an ultraviolet curable resin. Examples of the photocurable resin include photosensitive resins having a photoreactive group such as an acrylic resin, an epoxy resin, a polyimide resin, a polyvinyl cinnamate resin, and a cyclized rubber. One or more types can be used. In the acrylic resin, for example, a photosensitive resin composed of a polyfunctional acrylate monomer, a photopolymerization initiator, and other additives can be used as the resin component of the resin layer.
Examples of the polyfunctional acrylate monomers include trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and the like. The above can be used.
In the present invention, (meth) acrylate means either methacrylate or acrylate.

  As the photopolymerization initiator, one or more alkylphenone series, oxime ester series, triazine series, titanate series and the like can be used. For example, in the alkylphenone series, 2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropan-1-one (Irgacure (registered trademark) 907, manufactured by BASF Japan Ltd.), 2-benzyl- In 2-dimethylamino-1- (4-monofoliophenyl) butanone-1 (Irgacure (registered trademark) 369, manufactured by BASF Japan Ltd.), an oxime ester system, 1,2-octanedione, 1- [4- ( Phenylthio) phenyl]-, 2- (O-benzoyloxime) (Irgacure (registered trademark) OXE01, manufactured by BASF Japan Ltd.) and the like can be used.

  In addition, the other resin layer may include refractive index adjusting particles. As the refractive index adjusting particles, for example, it is preferable that the refractive index adjusting particles impart a refractive index corresponding to the above-described high refractive index layer to the resin layer.

Examples of the refractive index adjusting particles include metal oxide particles.
Examples of the metal oxide used for the metal oxide particles include zinc oxide, titanium oxide, cerium oxide, aluminum oxide, silane oxide, tantalum oxide, yttrium oxide, zirconium oxide, and antimony oxide. These metal oxides may be used alone or in combination of two or more.
Further, the surface of the refractive index adjusting particles can be modified with various coupling agents as required. Examples of the various coupling agents include metal alkoxides and organic acid salts obtained by organic substitution of silicon compounds, aluminum, titanium, zirconium, antimony, and the like.

The average particle diameter of the refractive index adjusting particles is not particularly limited as long as the resin layer constituting the invisible layer can be formed, but is within the range of 5 nm to 200 nm, particularly within the range of 10 nm to 100 nm. It is preferable to be within the range of 10 nm to 60 nm.
This is because if the average particle size of the refractive index adjusting particles is too small or too large, it may be difficult to adjust the refractive index of the resin layer. Further, when the average particle diameter of the refractive index adjusting particles is too large, there is a possibility that the strength of the resin layer is reduced or light scattering occurs.
Here, an average particle diameter is an average particle diameter by microscopic observation. The average particle diameter by microscopic observation is obtained, for example, by performing microscopic observation at a magnification of 100, measuring 100 particle diameters of arbitrary particles with image processing software or the like, and averaging the number. The particle diameter refers to the average value of the major axis diameter and minor axis diameter of the particles.

The content of the refractive index adjusting particles is not particularly limited as long as a predetermined refractive index can be imparted to the resin layer constituting the invisible layer, but per 100 parts by mass of the resin contained in the resin layer, It is preferably in the range of 20 parts by mass to 90 parts by mass, especially in the range of 40 parts by mass to 80 parts by mass, and particularly in the range of 60 parts by mass to 80 parts by mass.
This is because if the content of the refractive index adjusting particles is large, the resin layer may become brittle or it may be difficult to form the resin layer itself. Further, if the content of the refractive index adjusting particles is small, it may be difficult to sufficiently adjust the refractive index of the resin layer.

The thickness of the other resin layer is not particularly limited as long as the invisible layer can be formed. For example, the thickness is in the range of 5 nm to 200 nm, particularly in the range of 10 nm to 100 nm, particularly in the range of 10 nm to 50 nm. It is preferable that
This is because if the thickness of the other resin layer is too large, the thickness of the invisible layer itself increases, so that rainbow unevenness due to light interference may be observed. Moreover, it is because it may become difficult to form a resin layer favorable on the whole surface on a glass substrate when the thickness of said other resin layer is too thin.

(3) Invisible layer The thickness of the entire invisible layer in the present invention is not particularly limited as long as the bone appearance of the transparent electrode layer can be suppressed when it is used as a touch panel sensor, but in the range of 10 nm to 400 nm. However, it is preferably in the range of 20 nm to 200 nm, particularly in the range of 20 nm to 100 nm.
This is because if the thickness of the entire invisible layer is too thin, it may be difficult to form a good invisible layer on the glass substrate. If the entire thickness of the invisible layer is too thick, light interference may occur. This is because rainbow unevenness may occur.

The transmittance of the invisible layer is not particularly limited, but is preferably 80% or more, more preferably 90% or more, and particularly preferably 95% or more.
This is because if the transmittance of the invisible layer is small, the display image may be difficult to see when used with a display device as a touch panel.
The transmittance of the invisible layer is, for example, the total light transmittance measured using a haze meter (trade name: NDH2000, manufactured by Nippon Denshoku Industries Co., Ltd.).

As a method for designing the invisible layer, a known method can be used, and examples thereof include the following methods.
First, in the touch panel sensor, the optical characteristic target is set so that the difference in reflectance, the difference in transmittance, and the transmission color difference between the portion where the transparent electrode layer is formed and the portion where the transparent electrode layer is not formed are respectively desired values. Set the value. Next, based on the thickness and refractive index of each layer of the invisible layer and the thickness and refractive index of the transparent electrode layer used when the touch panel sensor is used, a difference in reflectance, a difference in transmittance, The optical characteristic value of the transmission color difference is obtained. Next, using the thickness and refractive index of each layer of the invisible layer as variable parameters, the thickness and refractive index of each layer of the invisible layer capable of achieving the target value of the optical property described above are calculated. A visualization layer can be designed. The simulation described above can be performed using, for example, thin film design software (OPTAS-FILM) manufactured by Cybernet Systems. The details of the design method of the invisible layer are the same as the contents described in Japanese Patent Application Laid-Open No. 2012-146217, and thus the description thereof is omitted here.

Moreover, as a formation method of an invisible layer, it can be made to be the same as the formation method of the resin layer used for a general touch panel sensor.
Specifically, a coating film is formed by applying a resin composition for forming the other layer on a glass substrate. Next, the coating film is cured to form the other layer. When the other layer is a layer containing a thermosetting resin, the curing process is performed by heating. On the other hand, when the other layer is a layer containing a photocurable resin, a curing process is performed by light irradiation. Under the present circumstances, you may heat-process the said coating film further as needed. Next, the uppermost layer-forming resin composition for forming the uppermost layer is applied on the other layers to form a coating film. Next, the uppermost layer is formed by heating and curing the coating film.

  The uppermost layer forming resin composition and the resin composition for forming other layers may contain a solvent as necessary. The solvent can be general.

  The coating method for the uppermost layer-forming resin composition or the like can be the same as the method used for a general resin layer forming method, for example, spin coating, die coating, spray coating, dip coating. Method, roll coating method, bead coating method, bar coating method and the like.

The heating temperature of the curing treatment by heating can be appropriately selected according to the type of the thermosetting resin, and is not particularly limited. For example, it is in the range of 150 ° C to 250 ° C, particularly 180 ° C to 240 ° C. It is preferable to be in the range, particularly in the range of 200 ° C to 230 ° C.
If the heating temperature is low, it may be difficult to sufficiently cure the uppermost layer, and if the heating temperature is high, the resin layer constituting the invisible layer may be modified. It is.

  About the photocuring process and the heat processing performed with a photocuring process, it can be made to be the same as that of the method used as a formation method of a general resin layer.

2. Glass substrate The glass substrate in this invention supports the invisible layer mentioned above.

  As the glass substrate, the type of glass is not particularly limited as long as the above-described invisibility layer can be formed and can be used as a support base material of the touch panel sensor.

The thickness of the glass substrate is not particularly limited as long as the above-described invisibility layer can be formed and can be used as a support base material of the touch panel sensor, but it is within a range of 50 μm to 1500 μm, and in particular, 400 μm. It is preferable to be within a range of ˜1000 μm, particularly within a range of 500 μm to 700 μm.
It is because it may become difficult to give sufficient intensity | strength to the board | substrate for touchscreen sensors of this invention when the thickness of a glass substrate is too thin. On the other hand, when the glass substrate is too thick, it may be difficult to reduce the thickness and weight of the touch panel sensor using the touch panel sensor substrate.

The refractive index of the glass substrate is appropriately determined according to the type of the glass substrate, and is not particularly limited, but is usually in the range of 1.40 to 1.60, particularly 1.45 to 1.5. It is preferable to be within the range of 55.
The refractive index of the glass substrate is a value calculated by measurement using an ellipsometer at a wavelength of 550 nm.

3. Other Configurations The touch panel sensor substrate of the present invention is not particularly limited as long as it can have the glass substrate and the invisible layer described above, and other configurations can be appropriately selected and added as necessary. As such a structure, for example, a full-surface transparent electrode layer formed on the entire surface of the invisible layer and containing an inorganic conductive material can be exemplified. The inorganic conductive material used for the entire transparent electrode layer and the thickness thereof can be the same as those used for the transparent electrode layer described in the section “B. Touch panel sensor” described later. Description of is omitted.

B. Touch Panel Sensor The touch panel sensor of the present invention includes a glass substrate, an invisible layer formed on the glass substrate, including a transparent resin, and made of a laminate of a plurality of resin layers having different refractive indexes, and the invisible A transparent electrode layer including an inorganic conductive material formed in a pattern on the layer, wherein the invisible layer is a layer in which the uppermost layer of the laminate includes a thermosetting resin. To do.

The touch panel sensor of this invention is demonstrated using figures.
FIG. 3A is a schematic plan view showing an example of the touch panel sensor of the present invention, and FIG. 3B is a cross-sectional view taken along line AA in FIG. As shown in FIGS. 3A and 3B, the touch panel sensor 10 of the present invention includes a glass substrate 2 and a plurality of resin layers formed on the glass substrate 2 and including a transparent resin and having different refractive indexes. It has the invisible layer 3 comprised by the laminated body, and the transparent electrode layer 4 formed in pattern shape on the invisible layer 3, and containing an inorganic electroconductive material. The invisible layer 3 can be the same as the content described with reference to FIG. 1 described above, and a description thereof is omitted here.
In the touch panel sensor 10 shown in FIGS. 3A and 3B, the transparent electrode layer 4 includes a sensor electrode having a first electrode 41 and a second electrode 42 formed in an active area, and the first electrodes 41. An example of a conductive part having a first conductive part 43 to be connected and a second conductive part 44 for connecting the second electrodes 42 to each other is shown. 3A and 3B, the first electrode 41 and the first conductive portion 43 are formed on the invisible layer 3 formed on one surface of the glass substrate 2, and the insulating layer 6 In this example, the second electrode 42 and the second conductive portion 44 are further formed via the. 3 (a) and 3 (b), the extraction wiring 51 connected to the first electrode 41 or the second electrode 42 on the outside of the active area on the invisibility layer 3 and the insulating layer 6, respectively, An example in which the external connection terminal 52 is formed is shown. For ease of explanation, the invisible layer and the insulating layer are omitted in FIG.

  According to this invention, it can be set as the cheap touch panel sensor with little deterioration of an invisible layer by having the invisible layer which has the said structure.

  Hereinafter, details of the touch panel sensor of the present invention will be described. In addition, about the glass substrate in this invention, and the invisible layer, since it can be made to be the same as that of the content demonstrated by the term of the "A. touch-panel sensor board | substrate" mentioned above, description here is abbreviate | omitted.

1. Transparent electrode layer The transparent electrode layer in this invention is a layer which is formed in a pattern shape on an invisible layer, and contains an inorganic electroconductive material.

  As the inorganic conductive material used in the present invention, those used for a general touch panel sensor can be used. For example, indium tin oxide (ITO), zinc oxide, indium oxide, antimony-added tin oxide, fluorine Additive tin oxide, aluminum-added zinc oxide, potassium-added zinc oxide, silicon-added zinc oxide, metal oxides such as zinc oxide-tin oxide system, indium oxide-tin oxide system, zinc oxide-indium oxide-magnesium oxide system, Examples thereof include materials in which two or more of these metal oxides are combined.

The conductivity of the transparent electrode layer used in the present invention is not particularly limited as long as it can function as an electrode of a touch panel sensor. In the present invention, the surface resistance of the transparent electrode layer is preferably in the range of, for example, 10Ω / □ to 100Ω / □, and more preferably in the range of 10Ω / □ to 30Ω / □. It is preferably within the range of 14Ω / □ to 22Ω / □. This is because the sensor electrode can be made highly sensitive by the sheet resistance.
The surface resistance of the transparent electrode layer can be confirmed using a Loresta GP MCP-T601 type (conforming to JIS K7194) by a four-terminal four-probe method and a constant current application method.

The thickness of the transparent electrode layer is not particularly limited as long as it can exhibit predetermined conductivity. For example, the thickness is in the range of 30 nm to 200 nm, particularly in the range of 100 nm to 180 nm, and particularly in the range of 130 nm to 150 nm. It is preferable. This is because if the thickness of the transparent electrode layer is too thin, it may not function sufficiently as an electrode. If the thickness of the transparent electrode layer is too thick, cracks, peeling, etc. may easily occur in the transparent electrode layer. Because there is.
About the thickness of a transparent electrode layer, it can measure using the observation image of a transmission electron microscope (TEM), for example.

The refractive index of the transparent electrode layer is appropriately determined according to the material of the transparent electrode layer, but is usually in the range of 1.70 to 2.20, particularly 1.80 to 2.00. It is preferable to be within the range.
The refractive index of the transparent electrode layer is a value calculated by measurement using an ellipsometer at a wavelength of 550 nm.

  As a method for forming the transparent electrode layer in the present invention, a photolithography method can be suitably used. Specifically, the touch panel sensor substrate described above is prepared, and a transparent electrode layer is formed on the entire surface of the invisible layer. Next, a resist is applied on the transparent electrode layer to form a coating film, and the coating film is exposed through a photomask or the like and then developed to form a resist layer having a predetermined pattern shape. Next, the exposed portion of the transparent electrode layer is etched to form the transparent electrode layer in a predetermined pattern shape. Next, the transparent electrode layer described above can be formed by peeling the resist layer.

As a method for forming the transparent electrode layer, a general method can be used, and examples thereof include a method using a dry process such as a vacuum deposition method, a sputtering method, a CVD method, and an ion plating method.
Moreover, as an etching liquid used for the etching of a transparent electrode layer, it sets suitably according to the inorganic electroconductive material etc. which comprise the said transparent electrode layer. Specifically, when the transparent electrode layer is made of ITO, a mixed aqueous solution of ferric chloride and hydrochloric acid, hydrochloric acid, oxalic acid, hydrobromic acid, or the like can be used.
The resist can be the same as that used in general photolithography. Examples of the resist developer and the resist stripper include an aqueous potassium hydroxide solution.

  Although it will not specifically limit if it is an electrode used for a touch panel sensor as a transparent electrode layer, It is preferable that it is a sensor electrode formed in an active area.

2. Electrode of touch panel sensor The electrode used in the touch panel sensor of the present invention can be appropriately selected according to the form of the touch panel sensor. If the touch panel sensor is of the capacitive type, it is formed in the active area. Sensor electrodes and conductive parts to be formed, lead wires formed outside the active area, and external connection terminals.

(1) Sensor electrode The sensor electrode in the present invention includes a first electrode and a second electrode insulated from the first electrode, is formed in the active area, and is used to detect a contact position.
In addition, the 2nd electrode insulated from the 1st electrode means that both electrodes are not electrically connected.

  The sensor electrode in the present invention may be the transparent electrode layer described above or not the transparent electrode layer, but is preferably a transparent electrode layer.

As the planar view shape and the planar view outer shape of the sensor electrode, for example, JP 2011-210176 A, JP 2010-238052 A, JP 4610416 A, JP 2010-286886 A, and JP 2004. Used for general touch panel sensors such as those described in JP-A-202093, JP-A 2010-277392, JP-A 2011-129501, JP-A 2013-156773, and JP-A 2013-143059 And can be similar.
In the present invention, the planar shape of the sensor electrode is preferably a planar shape that does not include an opening. Further, the outer shape of the sensor electrode in plan view can be specifically a polygonal shape such as a rectangle or a substantially square shape in plan view.

Moreover, as a formation location with respect to the glass substrate of the 1st electrode and 2nd electrode in this invention, if it is formed in the active area of a touch panel sensor and both are insulated, it will not specifically limit. For example, as shown in FIGS. 4A to 4C, both the first electrode 41 and the second electrode 42 are formed on the invisible layer 3 formed on one surface of the glass substrate 2. As shown in FIGS. 3A and 3B, the first electrode 41 is formed on the invisible layer 3 formed on one surface of the glass substrate 2, and the first electrode 41 is interposed through the insulating layer 6. Two electrodes 42 may be formed. Further, as shown in FIGS. 5A and 5B, when the invisible layer 3 is provided on both surfaces of the glass substrate 2, the first electrode 41 is formed on one of the invisible layers 3, and the other invisible A second electrode 42 may be formed on the visualization layer 3.
Although not shown, two touch panel sensor substrates described above may be prepared, and the first electrode and the second electrode may be separately formed on the invisible layer of each touch panel sensor substrate.
4A is a schematic plan view showing another example of the touch panel sensor of the present invention, FIG. 4B is a cross-sectional view taken along line AA of FIG. 4A, and FIG. ) Is a sectional view taken along line BB in FIG. FIG. 5A is a schematic plan view showing another example of the touch panel sensor of the present invention, and FIG. 5B is a cross-sectional view taken along line AA of FIG.

(2) Conductive part The conductive part in this invention contains the 1st conductive part and 2nd conductive part which connect between the 1st electrodes which comprise the said sensor electrode, and between 2nd electrodes, respectively.
Further, the first conductive portion and the second conductive portion are usually formed so that a part thereof overlaps in plan view.

  The above-mentioned conductive part may be the transparent electrode layer mentioned above, and may not be a transparent electrode layer. When the conductive part is not a transparent electrode layer, examples of the conductive material used for the conductive part include metals such as aluminum, molybdenum, silver, and chromium, and alloys thereof.

  The external shape of the conductive part in plan view can be the same as that of a general touch panel sensor. For example, the line shape is narrower than the external shape of the sensor electrode in plan view, and is equivalent to the external shape of the sensor electrode in plan view. A line shape having a width can be used.

In addition, the first conductive portion and the second conductive portion are formed so that the first electrode and the second electrode can be stably connected to each other and are insulated from each other. There is no particular limitation as long as it is present. For example, when the first electrode 41 and the second electrode 42 are formed on different surfaces or different members as shown in FIGS. 3 and 5, the first conductive portion 43 and the second conductive portion are formed. The portions 44 may be formed on the same surface as the first electrode 41 and the second electrode 42, respectively.
As shown in FIG. 4, when both the first electrode 41 and the second electrode 42 are formed on one surface of the same glass substrate 2, the first conductive portion 43 and the second conductive portion 44 are It can be formed via the insulating layer 6.

(3) Extraction wiring The extraction wiring in the present invention is connected to the sensor electrode. As the location where the lead-out wiring is formed, it is appropriately set according to the type and application of the touch panel sensor of the present invention, but when the touch panel sensor of the present invention is used for a display device with a touch panel, It is formed in an inactive area.
The extraction wiring may be the above-described transparent electrode layer, or may not be the above-described transparent electrode layer. Usually, it is preferable that the lead-out wiring is not the transparent electrode layer described above.
When the lead-out wiring is not the transparent electrode layer, the conductive material used to form the lead-out wiring is specifically composed of silver, gold, chromium, platinum, aluminum alone or any one of them. An alloy to be used can be exemplified. As the metal alloy, APC, that is, a silver / palladium alloy is generally used. Further, as the metal composite, MAM (Mo—Al—Mo, that is, a three-layer structure of molybdenum, aluminum, and molybdenum) can be used.

  The line width of the extraction wiring can be the same as that of a general touch panel sensor, and can be, for example, about 0.01 mm to 0.2 mm.

(4) External connection terminal The external connection terminal in this invention is connected to the said extraction wiring, for example, is used for connection with the external structure of touch panel sensors, such as a flexible printed wiring board.

As a conductive material in the case where the external connection terminal is formed and the external connection terminal is not a transparent electrode layer, it can be generally used for a touch panel sensor. The same can be said.
About the terminal width of the said external connection terminal, thickness, and planar view shape, and the space | interval between the external connection terminals in an external connection terminal part can be made to be the same as that of a general touch panel sensor. Specifically, it can be the same as that described in JP2011-210176A.

3. Other Configurations The touch panel sensor of the present invention is not particularly limited as long as it includes the glass substrate, the invisible layer, and the transparent electrode layer described above, and other configurations are appropriately selected and added as necessary. be able to.
Examples of such a configuration include an insulating layer and a coating layer.

(1) Insulating layer The insulating layer is formed to prevent a short circuit between the first electrode and the second electrode constituting the sensor electrode.
The details of the insulating layer can be the same as those described in JP 2013-210733 A, for example.

(2) Coating layer The coating layer is not particularly limited as long as it has insulating properties, but when it is formed so as to cover the wiring layer, it has transparency. It is preferable that
Examples of such an insulating and transparent coating layer include those made of an inorganic material such as an acrylic resin or SiO ₂ .

4). Manufacturing method The manufacturing method of the touch panel sensor of this invention will not be specifically limited if the touch panel sensor which has each structure mentioned above can be manufactured. Moreover, since the manufacturing method of each structure of the touchscreen sensor of this invention has already been demonstrated, description here is abbreviate | omitted.

5. Others The touch panel sensor of the present invention has the above-described invisible layer so that the optical characteristics of the pattern formation region and the non-pattern formation region are adjusted. About the optical characteristic of a pattern formation area | region and a non-pattern formation area | region, it can adjust suitably according to the use of the touch panel sensor of this invention.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  The details of the touch panel sensor substrate and touch panel of the present invention will be described below with reference to examples and comparative examples.

[Example 1]
(Preparation)
The following resin composition for high refractive index layers was prepared.
<Composition of resin composition for high refractive index layer>
-UV curable resin composition based on acrylic resin: 30% by mass
-Titanium oxide particles (average particle size 30 nm): 70% by mass
The refractive index of the high refractive index layer using the above resin composition for high refractive index layer was 1.75.

As the low refractive index layer resin composition, a thermosetting resin composition containing an epoxy resin as a main component was used.
The refractive index of the low refractive index layer using the above resin composition for low refractive index layer was 1.55.

  A glass substrate having a thickness of 0.55 mm and a refractive index of 1.51 was prepared as a glass substrate.

(Production of touch panel sensor substrate)
After spin-coating the resin composition for a high refractive index layer to a thickness of 30 nm on the glass substrate, it was cured at an exposure amount of 200 mJ / cm ² in an air atmosphere, and then dried at 230 ° C. for 25 minutes. A high refractive index layer was obtained.

Next, the low refractive index layer resin composition was spin-coated on the high refractive index layer to a thickness of 30 nm, and then dried at 230 ° C. for 25 minutes to obtain a low refractive index layer.
Through the above steps, a touch panel sensor substrate was obtained.

[Example 2]
A touch panel sensor substrate was produced in the same manner as in Example 1 except that the high refractive index layer was formed as follows.
The following high refractive index resin composition was prepared.
<Composition of resin composition for high refractive index layer>
-Thermosetting resin composition mainly composed of epoxy resin: 30% by mass
-Titanium oxide particles (average particle size 30 nm): 70% by mass
The refractive index of the high refractive index layer using the above resin composition for high refractive index layer was 1.75.

  The high refractive index layer resin composition was spin-coated on the glass substrate so as to have a thickness of 30 nm, and then dried at 230 ° C. for 25 minutes to obtain a high refractive index layer.

[Comparative example]
A touch panel sensor substrate was produced in the same manner as in Example 1 except that the low refractive index layer was formed as follows.
As a resin composition for a low refractive index layer, a UV curable resin composition mainly composed of an acrylic resin was prepared.
The refractive index of the low refractive index layer using the above resin composition for low refractive index layer was 1.55.

The low refractive index layer resin composition is spin-coated on the high refractive index layer so as to have a thickness of 30 nm, cured at an exposure amount of 200 mJ / cm ² in an air atmosphere, and then dried at 230 ° C. for 25 minutes. Thus, a low refractive index layer was obtained.
Through the above steps, a touch panel sensor substrate was obtained.

[Evaluation]
Each of the obtained touch panel sensor substrates was immersed in the following solutions maintained at a constant temperature, and the time until the peeling of the invisible layer could be confirmed visually was measured.
The results are shown in Table 1.
・ Alkaline solution: 2% KOH aqueous solution ・ Acid solution: 48% HBr aqueous solution

When the substrate for touch panel sensors of the comparative example was immersed in an alkaline aqueous solution, the invisible layer was peeled off in less than 1 minute.
It was confirmed that both the alkali resistance and acid resistance of the invisible layer can be improved in the touch panel sensor substrates of Examples 1 and 2 as compared with the comparative example.

DESCRIPTION OF SYMBOLS 1 ... Substrate for touch panel sensors 2 ... Glass substrate 3 ... Invisible layer 4 ... Transparent electrode layer 10 ... Touch panel sensor 31 ... High refractive index layer 32 ... Low refractive index layer 41 ... 1st electrode 42 ... 2nd electrode 43 ... 1st Conductive part 44 ... second conductive part

Claims (7)

A glass substrate;
An invisible layer formed on one surface of the glass substrate, comprising a transparent resin and composed of a laminate of a plurality of resin layers having different refractive indexes;
Have
The invisible layer is a touch panel sensor substrate, wherein an uppermost layer of the laminate includes a thermosetting resin.   The touch panel sensor substrate according to claim 1, wherein the uppermost layer is a low refractive index layer, and the resin layer in contact with the uppermost layer is a high refractive index layer.   The touch panel sensor substrate according to claim 1, wherein the resin layer formed in the lower layer of the uppermost layer is a layer containing a photocurable resin.   The touch panel sensor substrate according to claim 1, wherein the resin layer formed in the lower layer of the uppermost layer is a layer containing a thermosetting resin.   The touch panel sensor substrate according to any one of claims 1 to 4, wherein the uppermost layer does not contain particles for adjusting a refractive index.   The touch panel sensor substrate according to any one of claims 1 to 5, wherein the uppermost layer has a thickness of 200 nm or less. A glass substrate;
An invisible layer formed of a laminate of a plurality of resin layers formed on the glass substrate, including a transparent resin and having different refractive indexes;
A transparent electrode layer formed in a pattern on the invisible layer and containing an inorganic conductive material;
Have
The invisible layer is a touch panel sensor, wherein the uppermost layer of the laminate is a layer containing a thermosetting resin.

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