JP2018136645A - Image display unit with position detection function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image display unit with a position detection function that never spoils writing properties based upon a touch pen, suppresses glaring, and has excellent visibility for a display image.SOLUTION: An image display unit 1A with a position detection function comprises at least a writing-property improvement layer 10 that a touch pen is brought into contact with, a display body module 4 having a color filter 44, and a light diffusion layer 30 provided at an arbitrary position between the writing-property improvement layer 10 and display body module 4. The total haze from the writing-property improvement layer 10 to the light diffusion layer 30 is 12-45%, and the distance between the light diffusion layer 30 and color filter 44 is 4 mm or less.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an image display device with a position detection function in which a touch pen is used.

  In recent years, in various electronic devices, an image display device with a position detection function (touch panel) that serves both as a display device and an input unit has been widely used. In such a touch panel, there is an input by a touch pen in addition to an input by a finger. According to the touch pen, an input operation that is finer and more accurate than a finger is possible. However, the display module of a touch panel is usually hard. Therefore, the writing taste with a touch pen is not good, unlike the writing taste when writing on paper with a pencil or pen.

  In order to solve the problem of writing quality with a touch pen in a touch panel, it has been studied to apply a film for improving writing quality (hereinafter sometimes referred to as “writing quality improving film”) on the outermost surface of the touch panel. Yes. As such a film, for example, Patent Document 1 includes a transparent base film and linear protrusions that form a network structure on at least one surface of the transparent base film, and the network structure is regularly arranged. There is disclosed a tactile film having a plurality of sections and having a linear convex portion occupying an area of 5 to 80% with respect to the entire tactile film surface.

JP2015-054417A

  However, the conventional writing quality improving film sometimes scatters the image light of the touch panel, and the phenomenon that the portion glitters and so-called “glare” sometimes occurs.

  The present invention has been made in view of such a situation, and provides an image display device with a position detection function in which glare is suppressed and visibility of a display image is good without impairing writing quality with a touch pen. The purpose is to do.

  In order to achieve the above object, firstly, the present invention provides at least a writing quality improving layer to which a touch pen comes in contact, a display module having a color filter, and an arbitrary combination between the writing quality improving layer and the display module. And a total haze from the writing quality improving layer to the light diffusing layer is not less than 12% and not more than 45%, and the distance between the light diffusing layer and the color filter Provides an image display device with a position detection function, characterized in that it is 4 mm or less (Invention 1). Here, the “writing quality improving layer” in the present specification refers to a layer in which the writing quality with a touch pen is improved as compared with the case without the writing quality improving layer. For example, the touch pen is used directly on the base film. A layer with improved writing quality.

  In the said invention (invention 1), the said total haze and the distance of a light-diffusion layer and a color filter are set as mentioned above, a glare is suppressed and the visibility of a display image becomes favorable. . Further, the above physical properties and configuration do not impair the writing quality of the touch pen by the writing quality improving layer.

  In the said invention (invention 1), the said image display apparatus with a position detection function is equipped with the base film, and the said writing quality improvement layer is provided in the one surface side of the said base film. Preferred (Invention 2).

  In the above inventions (Inventions 1 and 2), the pen tip of the hard felt core touch pen having a pen tip diameter of 0.5 mm is applied to the surface of the touch improvement layer of the writing quality improving layer in contact with a pressure of 3.92 N. The pen tip resistance was measured while contacting in the vertical direction and moving at a speed of 100 mm / min in any direction parallel to the surface of the writing quality improving layer, and a chart of the obtained moving distance-pen tip resistance was obtained. The average value of the amplitude in the frequency range of 1 to 2 Hz obtained from the frequency-amplitude chart obtained by performing Fourier transform and conversion is 1.0 or more and 10 or less, and the peak number of the amplitude is 4 As mentioned above, it is preferable that it is 30 or less (invention 3).

  In the said invention (invention 1-3), it is preferable that the said writing quality improvement layer is a layer formed by hardening | curing the coating composition containing a sclerosing | hardenable component and microparticles | fine-particles (invention 4).

  In the said invention (invention 1-4), it is preferable that the said light-diffusion layer is a layer formed from the adhesive composition containing an adhesion component and light-diffusion microparticles | fine-particles (invention 5).

  In the said invention (invention 1-5), it is preferable that the said light-diffusion layer is provided so that it may adjoin to the said display body module (invention 6).

  In the said invention (invention 2), it is preferable that the said light-diffusion layer is provided so that it may adjoin to the said base film in which the said writing quality improvement layer was provided (invention 7).

  The image display device with a position detection function according to the present invention is capable of suppressing glare without impairing the writing quality with a touch pen, and has good visibility of a display image.

It is sectional drawing of the image display apparatus with a position detection function which concerns on the 1st Embodiment of this invention. It is sectional drawing of the image display apparatus with a position detection function which concerns on the 2nd Embodiment of this invention. It is sectional drawing of the image display apparatus with a position detection function which concerns on the 3rd Embodiment of this invention. It is sectional drawing of the image display apparatus with a position detection function which concerns on the 4th Embodiment of this invention. It is sectional drawing of the image display apparatus with a position detection function which concerns on the 5th Embodiment of this invention. It is sectional drawing of the image display apparatus with a position detection function used by the comparative example. It is sectional drawing of the image display apparatus with a position detection function used by the comparative example.

Hereinafter, embodiments of the present invention will be described.
An image display device with a position detection function according to an embodiment of the present invention (hereinafter sometimes referred to as “touch panel”) includes at least a writing quality improving layer that a touch pen contacts, a display module having a color filter, and the above And a light diffusion layer provided at an arbitrary position between the writing quality improving layer and the display module. Below, it demonstrates, showing a specific example.

[First Embodiment]
As shown in FIG. 1, the touch panel 1 </ b> A according to the first embodiment of the present invention includes a writing quality improving layer 10 that is in contact with the touch pen and a side on which the touch pen of the writing quality improving layer 10 is not in contact (the lower side in FIG. 1). ), The base film 21 on which the writing quality improving layer 10 is formed, the first pressure-sensitive adhesive layer 22a for bonding the base film 21, and the first pressure-sensitive adhesive layer 22a to the above It was bonded to the cover material 23 via the cover material 23 to which the base film 21 was bonded, the second pressure-sensitive adhesive layer 22b for bonding the cover material 23, and the second pressure-sensitive adhesive layer 22b. Bonded to the first touch sensor 24a via the first touch sensor 24a, the third adhesive layer 22c for bonding the first touch sensor 24a, and the third adhesive layer 22c. A second touch sensor 24b and a second touch sensor; The light diffusion layer 30 having an adhesive for bonding the over 24b, constituted by a display body module 4 second touch sensor 24b via the light diffusing layer 30 is stuck.

  The display module 4 is not particularly limited as long as it has a color filter. Usually, a liquid crystal (LCD) module, a light emitting diode (LED) module, an organic electroluminescence (organic EL) module, or the like is used. . FIG. 1 shows a liquid crystal module as an example. The display module 4 according to the present embodiment includes a first glass substrate 41a adjacent to the light diffusion layer 30, a module adhesive layer 42 located below the first glass substrate 41a, and a module adhesive layer 42. A first polarizing plate 43a located below, a second glass substrate 41b located below the first polarizing plate 43a, and a color filter 44 located below the second glass substrate 41b, The liquid crystal layer 45 positioned below the color filter 44, the third glass substrate 41c positioned below the liquid crystal layer 45, and the second polarizing plate 43b positioned below the third glass substrate 41c. And a backlight 47 located below the second polarizing plate 43b.

1. Physical Properties In the touch panel 1A according to the present embodiment, the total haze from the writing quality improving layer 10 to the light diffusion layer 30 is 12% or more and 45% or less. When the total haze is 12% or more, glare in the touch panel can be suppressed. Further, when the total haze is 45% or less, it is possible to suppress white browning and blurring of the display image, and it is possible to maintain good visibility of the display image. In addition, the total haze from the writing quality improving layer 10 to the light diffusion layer 30 in the touch panel 1A according to the present embodiment is the writing quality improving layer 10, the base film 21, the first adhesive layer 22a, the cover material 23, the first. The haze of the entire laminate of the second pressure-sensitive adhesive layer 22b, the first touch sensor 24a, the third pressure-sensitive adhesive layer 22c, the second touch sensor 24b, and the light diffusion layer 30 (total of internal haze and external haze) is there. Moreover, the haze in this specification shall be the value measured according to JISK7136: 2000.

  From the viewpoint of suppressing glare, the total haze is preferably 14% or more, particularly preferably 16% or more, and more preferably 18% or more. Further, from the viewpoint of the visibility of the display image, the total haze is preferably 42% or less, particularly preferably 40% or less, and further preferably 38% or less.

  In the touch panel 1A according to the present embodiment, the distance between the light diffusion layer 30 and the color filter 44 is 4 mm or less. The distance between the light diffusion layer 30 and the color filter 44 refers to the distance between the surface of the light diffusion layer 30 on the color filter 44 side and the surface of the color filter 44 on the light diffusion layer 30 side. . When the distance exceeds 4 mm, the display image is whitened or blurred, and the visibility of the display image is reduced. That is, when the distance is 4 mm or less, the visibility of the display image can be maintained favorably.

  From the viewpoint of the visibility of the display image, the distance is preferably 3 mm or less. On the other hand, the lower limit of the distance is not particularly limited, but is usually 0.005 mm or more, preferably 0.01 mm or more.

  The physical properties related to the total haze and the configuration related to the distance between the light diffusion layer 30 and the color filter 44 do not impair the writing quality of the touch pen by the writing quality improving layer 10.

  Furthermore, in the touch panel 1A according to the present embodiment, the pen tip of a hard felt core touch pen having a pen tip diameter of 0.5 mm is pressed with a load of 3.92 N against the surface of the touch improving pen 10 of the writing quality improving layer 10 that comes into contact. The pen tip resistance (mN) was measured while moving at a speed of 100 mm / min in an arbitrary direction parallel to the surface of the writing quality improving layer 10 in contact with the surface in the vertical direction, and the obtained moving distance (mm) The frequency of the pen tip resistance (mN) is Fourier-transformed, and the frequency (Hz) obtained by the conversion is obtained. The average value of the amplitude in the frequency range of 1 to 2 Hz obtained from the amplitude chart (−) is 1 It is preferably 0.0 or more and 10 or less, and the number of amplitude peaks (amplitude number) is preferably 4 or more and 30 or less (the physical property by the pen sliding test is hereinafter referred to as “writing property”). If there is). Note that the Fourier transform is performed using software (product name “Excel” manufactured by Microsoft Corporation). When the average value of the amplitude and the number of amplitudes are in the above-described range, a favorable resistance feeling and friction feeling are imparted to the taste of writing with the touch pen. Together, these sensations make the touch pen writing feel close to the sensation of writing on paper with a pencil.

  The definition of the amplitude in the frequency range of 1 to 2 Hz is a characteristic that humans recognize as "writing taste" especially when the vibration at the time of writing is considered as a superposition of a plurality of vibrations having various frequencies. This is because the present inventors have empirically found that a simple vibration is a vibration having a frequency in the range of 1 to 2 Hz.

  In addition, as a touch pen, for example, a touch pen having a pen tip diameter of 0.1 to 5 mm, a polyacetal core touch pen, and the like can be used. Is obtained.

  Here, the “pen tip resistance” refers to the resistance applied to the pen tip when the touch pen is moved under the above conditions. The “number of peaks” refers to the number of peaks having an amplitude of 1.5 or more in a frequency range of 1 to 2 Hz.

  From the viewpoint of writing with a touch pen, the average value of the amplitude is preferably 1.5 or more. The average value of the amplitude is preferably 4 or less. The amplitude number is more preferably 5 or more, particularly preferably 6 or more, and more preferably 8 or more. The amplitude number is preferably 20 or less, more preferably 15 or less.

  From the viewpoint of further improving the writing quality with the touch pen, the maximum value of the amplitude (maximum amplitude value) is preferably 1.3 or more, particularly preferably 2.0 or more, and more preferably 2.4 or more. It is preferable that The maximum value of the amplitude is preferably 10 or less, particularly preferably 8 or less, and more preferably 5 or less.

  A specific method of obtaining the above moving distance (mm) -pen tip resistance force (mN) chart is as shown in a test example described later.

2. Each member (1) Writing quality improvement layer The writing quality improvement layer 10 in this embodiment is the layer which improved the writing quality of the touch pen rather than the case where a touch pen is used for the base film 21 directly. The writing quality improving layer 10 is preferably a coat layer formed on one surface side of the base film 21 by the coating composition, but is not limited thereto.

(1-1) Material of the writing quality improving layer The writing quality improving layer 10 of the touch panel 1A according to the present embodiment can improve the writing quality of the touch pen as compared with the case where the touch pen is directly used for the base film 21. In addition, any material may be used as long as it is made of a material having good optical characteristics, but it is preferably made of a material that satisfies the above-described writing taste properties. The writing quality improving layer 10 in the present embodiment is preferably formed by curing a coating composition C described below. According to the coating composition C, it is easy to form the writing quality improving layer 10 that satisfies the above-described writing quality properties.

  The coating composition C in this embodiment preferably contains a curable component and fine particles.

(1-1-1) Curable component A curable component is a component which hardens | cures with triggers, such as an active energy ray and a heat | fever, for example, an active energy ray curable component, a thermosetting component, etc. are mentioned. In the present embodiment, it is preferable to use an active energy ray-curable component from the viewpoint of the hardness of the writing quality improving layer 10 to be formed, the heat resistance of the base film 21 and the like.

  The active energy ray-curable component is preferably one that can be cured by irradiation with active energy rays to exhibit a predetermined hardness and achieve the above-mentioned writing properties in relation to the fine particles.

  Specific active energy ray curable components include polyfunctional (meth) acrylate monomers, (meth) acrylate prepolymers, active energy ray curable polymers, etc., among which polyfunctional (meth) acrylates. It is preferably a monomer and / or a (meth) acrylate prepolymer, and more preferably a polyfunctional (meth) acrylate monomer. The polyfunctional (meth) acrylate monomer and the (meth) acrylate prepolymer may be used alone or in combination. In the present specification, (meth) acrylate means both acrylate and methacrylate. The same applies to other similar terms.

  Examples of multifunctional (meth) acrylate monomers include 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, and polyethylene glycol diene. (Meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, caprolactone modified dicyclopentenyl di (meth) acrylate, ethylene oxide modified di (meth) acrylate phosphoric acid, allylation Cyclohexyl di (meth) acrylate, isocyanurate di (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, propionic acid modified dipenta Lithritol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, propylene oxide modified trimethylolpropane tri (meth) acrylate, tris (acryloxyethyl) isocyanurate, propionic acid modified dipentaerythritol penta (meth) acrylate, di Examples thereof include polyfunctional (meth) acrylates such as pentaerythritol hexa (meth) acrylate, ethylene oxide-modified dipentaerythritol hexa (meth) acrylate, and caprolactone-modified dipentaerythritol hexa (meth) acrylate. These may be used individually by 1 type and may be used in combination of 2 or more type.

  On the other hand, examples of the (meth) acrylate-based prepolymer include polyester acrylate-based, epoxy acrylate-based, urethane acrylate-based, polyol acrylate-based prepolymers, and the like.

  Examples of the polyester acrylate-based prepolymer include esterification of a hydroxyl group of a polyester oligomer having hydroxyl groups at both ends obtained by condensation of a polyvalent carboxylic acid and a polyhydric alcohol with (meth) acrylic acid, It can be obtained by esterifying the terminal hydroxyl group of an oligomer obtained by adding alkylene oxide to carboxylic acid with (meth) acrylic acid.

  The epoxy acrylate prepolymer can be obtained, for example, by reacting (meth) acrylic acid with an oxirane ring of a relatively low molecular weight bisphenol type epoxy resin or novolak type epoxy resin and esterifying it.

  The urethane acrylate-based prepolymer can be obtained, for example, by esterifying, with (meth) acrylic acid, a polyurethane oligomer obtained by a reaction between polyether polyol or polyester polyol and polyisocyanate.

  The polyol acrylate prepolymer can be obtained, for example, by esterifying the hydroxyl group of the polyether polyol with (meth) acrylic acid.

  The above prepolymers may be used alone or in combination of two or more.

  It is also preferable to use an organic-inorganic hybrid resin as the active energy ray-curable component. Preferred examples of the organic / inorganic hybrid resin include a substance obtained by bonding an organic compound having a polymerizable unsaturated group to silica fine particles via a silane coupling agent or the like. Note that the silica fine particles contained in the organic-inorganic hybrid resin have a binder function as a silica sol and are not included in the fine particles described later.

  When the organic-inorganic hybrid resin is used, the above-mentioned writing properties are easily obtained by the action of silica sol. Therefore, even if spherical organic fine particles are used as the fine particles to be described later, the writing quality properties can be easily obtained, whereby the optical properties of the formed writing quality improving layer 10 can be improved. .

(1-1-2) Fine particles The fine particles may be either inorganic fine particles or organic fine particles. For example, inorganic fine particles are preferable from the viewpoint of imparting a high surface hardness to the writing quality improving layer 10, and organic fine particles are preferable from the viewpoint of enhancing the optical properties of the writing quality improving layer 10. The shape of the fine particles may be spherical or non-spherical. When it is non-spherical, it may be indefinite, or may have a shape with a high aspect ratio such as a needle shape or a scale shape. The “indefinite shape” here is not a regular shape such as a spherical shape or an elliptical shape, but a shape having a large number of irregular corners or surfaces. The fine particles can be used singly or in combination of two or more.

  Examples of the inorganic fine particles include metal oxides such as silica, aluminum oxide, zirconium oxide, titanium oxide, zinc oxide, germanium oxide, indium oxide, tin oxide, indium tin oxide (ITO), antimony oxide, and cerium oxide; Examples thereof include fine particles made of metal fluorides such as magnesium fluoride and sodium fluoride. Among these, silica and aluminum oxide are preferable from the viewpoint of imparting high surface hardness and little influence on optical properties, silica is particularly preferable, and amorphous silica is more preferable. Note that the surface of the inorganic fine particles may be chemically modified with an organic compound or the like.

  Examples of organic fine particles include silicone fine particles, melamine resin fine particles, acrylic resin fine particles (for example, polymethyl methacrylate resin fine particles), acrylic-styrene copolymer fine particles, polycarbonate fine particles, polyethylene fine particles, polystyrene. Fine particles, benzoguanamine resin fine particles, and the like. Those resins may be cross-linked. Among the above, from the viewpoint of optical properties and hardness, acrylic resin fine particles are preferred, polymethyl methacrylate resin fine particles are particularly preferred, spherical polymethyl methacrylate resin fine particles are preferred, and true spherical crosslinked polymethyl methacrylate resin fine particles are preferred. Most preferred.

  In this embodiment, in order to obtain the above-described writing physical properties, it is preferable to use irregular fine particles having an average particle diameter of 0.5 μm or more and 15 μm or less, or spherical fine particles having an average particle diameter of 1.7 μm or more and 15 μm or less. .

  The average particle size of the amorphous fine particles is preferably 0.5 μm or more, particularly preferably 0.75 μm or more, and more preferably 1.0 μm or more. The average particle size of the amorphous fine particles is preferably 15 μm or less, more preferably 10 μm or less, particularly preferably 6 μm or less, and further preferably 3 μm or less. When the average particle size of the irregular fine particles is in the above range, the above-described writing physical properties are easily obtained. The average particle size of the fine particles in this specification is a value measured by a laser diffraction / scattering particle size distribution measuring device.

  The average particle diameter of the spherical fine particles is preferably 1.7 μm or more, particularly preferably 2.0 μm or more, and more preferably 2.5 μm or more. The average particle diameter of the spherical fine particles is preferably 15 μm or less, more preferably 10 μm or less, particularly preferably 7 μm or less, and further preferably 5 μm or less. When the average particle diameter of the spherical fine particles is in the above range, the above-mentioned writing physical properties are easily obtained.

As for the particle size distribution of the fine particles, the coefficient of variation (CV value) of the particle size represented by the following formula is preferably 20% or more from the viewpoint that the writing quality improving layer 10 forms the above-mentioned writing properties. In particular, it is preferably 40% or more, and more preferably 70% or more. From the same viewpoint, the CV value is preferably 200% or less, particularly preferably 175% or less, and more preferably 150% or less.
Coefficient of variation of particle size (CV value) (%) = (standard deviation particle size / average particle size) × 100
In addition, let the coefficient of variation (CV value) of a particle size be the value measured with the laser diffraction scattering type particle size distribution measuring apparatus (the product name "LA-920" by Horiba Ltd.).

  The content of the amorphous fine particles in the coating composition C is preferably 3% by mass or more, preferably 4% by mass or more, particularly preferably 5% by mass or more, and more preferably 7% by mass. The above is preferable. Further, the content of the amorphous fine particles is preferably 40% by mass or less, preferably 35% by mass or less, particularly preferably 30% by mass or less, and further preferably 20% by mass or less. Is preferred. When the content of the amorphous fine particles is in the above range, the above-described writing physical properties are easily obtained.

  The content of the spherical fine particles in the coating composition C is preferably 3% by mass or more, particularly preferably 4% by mass or more, and further preferably 5% by mass or more. The content of the spherical fine particles is preferably 40% by mass or less, particularly preferably 35% by mass or less, and further preferably 30% by mass or less. When the content of the spherical fine particles is in the above range, the above-mentioned writing physical properties are easily obtained.

(1-1-3) Photopolymerization initiator When ultraviolet rays are used as the active energy ray for curing the active energy ray-curable component, the coating composition C preferably contains a photopolymerization initiator. . By containing the photopolymerization initiator in this manner, the active energy ray-curable component can be efficiently polymerized, and the polymerization curing time and the amount of ultraviolet irradiation can be reduced.

  Examples of such a photopolymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylaminoacetophenone, 2,2-dimethoxy-2- Phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) Phenyl] -2-morpholino-propan-1-one, 4- (2-hydroxyethoxy) phenyl-2- (hydroxy-2-propyl) ketone, benzophenone, p-phenylbenzophenone, 4,4′-di Tylaminobenzophenone, dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 2-aminoanthraquinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone 2,4-diethylthioxanthone, benzyldimethyl ketal, acetophenone dimethyl ketal, p-dimethylaminobenzoate, oligo [2-hydroxy-2-methyl-1 [4- (1-methylvinyl) phenyl] propanone], 2 4,6-trimethylbenzoyl-diphenyl-phosphine oxide and the like. These may be used alone or in combination of two or more.

  The content of the photopolymerization initiator in the coating composition C is preferably 0.01 parts by mass or more, particularly 0.1 parts by mass or more with respect to 100 parts by mass of the active energy ray-curable component. It is preferable that it is 1 part by mass or more. In addition, the content of the photopolymerization initiator is preferably 20 parts by mass or less, particularly preferably 10 parts by mass or less, and further preferably 5 parts by mass or less.

(1-1-4) Other components The coating composition C may contain various additives in addition to the components described above. Examples of various additives include leveling agents, UV absorbers, antioxidants, light stabilizers, antistatic agents, silane coupling agents, anti-aging agents, thermal polymerization inhibitors, colorants, surfactants, and storage stability. Agents, plasticizers, lubricants, antifoaming agents, wettability improvers, coating surface improvers and the like.

(1-2) Thickness of the writing quality improving layer The thickness of the writing quality improving layer 10 is preferably 0.5 μm or more, more preferably 0.7 μm or more as a lower limit. It is preferably 0 μm or more, more preferably 1.3 μm or more. When the lower limit of the thickness of the writing quality improving layer 10 is as described above, the above-described writing physical properties are easily satisfied, and good scratch resistance is obtained. Further, the thickness of the writing quality improving layer 10 is preferably 20 μm or less as an upper limit, particularly preferably 15 μm or less, and further preferably 10 μm or less. When the upper limit of the thickness of the writing quality improving layer 10 is the above, mixing of residual solvent and bubbles resulting from the production process can be effectively prevented, and a good writing quality improving layer 10 can be obtained. The above-mentioned writing physical properties are easily satisfied.

(2) Substrate Film The substrate film 21 may be appropriately selected from those suitable for touch panels in which a touch pen is used, and a plastic film having good affinity with the writing quality improving layer 10 is preferably selected.

  Examples of such plastic films include polyester films such as polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate, polyolefin films such as polyethylene film and polypropylene film, cellophane, diacetyl cellulose film, triacetyl cellulose film, acetyl cellulose butyrate film, Polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene-vinyl acetate copolymer film, polystyrene film, polycarbonate film, polymethylpentene film, polysulfone film, polyether ether ketone film, polyether sulfone film, poly Etherimide film, fluororesin film Plastic films such as polyamide film, acrylic resin film, polyurethane resin film, norbornene polymer film, cyclic olefin polymer film, cyclic conjugated diene polymer film, vinyl alicyclic hydrocarbon polymer film, or laminates thereof A film is mentioned. Among these, a polyethylene terephthalate film, a polycarbonate film, a norbornene polymer film, and the like that can maintain the writing quality of the touch pen in the combination with the writing quality improving layer 10 described above are preferable, and a polyethylene terephthalate film is particularly preferable.

  Moreover, in the said base film 21, in order to improve adhesiveness with the layers (The writing quality improvement layer 10, the adhesive layer mentioned later, etc.) provided in the surface, a primer process on one side or both sides depending on necessity, Surface treatment can be performed by an oxidation method, an uneven method, or the like. Examples of the oxidation method include corona discharge treatment, chromic acid treatment, flame treatment, hot air treatment, ozone / ultraviolet treatment, and examples of the unevenness method include a sand blast method and a solvent treatment method. These surface treatment methods are appropriately selected according to the type of the base film 21. As an example, a plastic film, particularly a polyethylene terephthalate film, on which an easy adhesion layer is formed by primer treatment, is preferably used.

  The thickness of the base film 21 is preferably 15 to 300 μm, particularly preferably 30 to 200 μm, and more preferably 90 to 150 μm.

(3) Pressure-sensitive adhesive layer The first pressure-sensitive adhesive layer 22a, the second pressure-sensitive adhesive layer 22b, and the third pressure-sensitive adhesive layer 22c may be formed of a desired pressure-sensitive adhesive or pressure-sensitive adhesive sheet, respectively. As the pressure-sensitive adhesive constituting these pressure-sensitive adhesive layers, those usually used for optical applications can be used, for example, acrylic pressure-sensitive adhesives, rubber-based pressure-sensitive adhesives, silicone-based pressure-sensitive adhesives, urethane-based pressure-sensitive adhesives, Examples include polyester-based pressure-sensitive adhesives and polyvinyl ether-based pressure-sensitive adhesives. Among these, an acrylic pressure-sensitive adhesive that expresses desired adhesiveness and has excellent optical properties and durability is preferable.

  The thicknesses of the first pressure-sensitive adhesive layer 22a, the second pressure-sensitive adhesive layer 22b, and the third pressure-sensitive adhesive layer 22c are each preferably 5 to 1000 μm, particularly preferably 7 to 500 μm, It is preferable that it is 10-250 micrometers.

(4) Cover material The cover material 23 protects the touch sensors 24a and 24b and the display body module 4 of the touch panel 1A, and is generally composed mainly of a glass plate or a plastic plate. The glass plate is not particularly limited. For example, chemically strengthened glass, alkali-free glass, quartz glass, soda lime glass, barium / strontium-containing glass, aluminosilicate glass, lead glass, borosilicate glass, barium borosilicate glass. Etc. The plastic plate is not particularly limited, and examples thereof include an acrylic plate made of polymethyl methacrylate and the like, and a polycarbonate plate.

  In addition, a functional layer such as a hard coat layer, an antireflection layer, or an antiglare layer may be provided on one side or both sides of the glass plate or plastic plate, or a hard coat film, an antireflection film, or an antiglare film. Such optical members may be laminated.

  In the present embodiment, the cover material 23 may have a step due to a printing layer or the like on the surface on the second pressure-sensitive adhesive layer 22b side (not shown). This printed layer is generally formed in a frame shape in plan view.

  The thickness of the cover material 23 is preferably 10 to 3000 μm, particularly preferably 25 to 2000 μm, and further preferably 50 to 1500 μm.

(5) Touch sensor The 1st touch sensor 24a and the 2nd touch sensor 24b bear a function which detects the position of a touch location in touch panel 1A.

  Usually, the touch sensors 24a and 24b are preferably composed of a transparent film and a patterned transparent conductive film, but are not limited thereto. The positional relationship between the transparent film and the transparent conductive film is not particularly limited.

  Although it does not specifically limit as a transparent film, For example, a polyethylene terephthalate film, a polyethylene naphthalate film, a polycarbonate film, a polymethylmethacrylate film, a triacetylcellulose film, a polypropylene film etc. are used.

  Examples of the transparent conductive film include metals such as platinum, gold, silver and copper, oxides such as tin oxide, indium oxide, cadmium oxide, zinc oxide and zinc dioxide, tin-doped indium oxide (ITO), and zinc oxide-doped indium oxide. , Fluorine-doped indium oxide, antimony-doped tin oxide, fluorine-doped tin oxide, aluminum-doped zinc oxide and other complex oxides, non-oxidized compounds such as chalcogenides, lanthanum hexaboride, titanium nitride, titanium carbide, etc. Of these, those made of tin-doped indium oxide (ITO) are preferred.

  The thicknesses of the touch sensors 24a and 24b are each preferably 10 to 300 μm, particularly preferably 15 to 250 μm, and further preferably 20 to 200 μm.

(6) Light Diffusing Layer The light diffusing layer 30 in the present embodiment has adhesiveness for bonding the second touch sensor 24b and the display body module 4, and preferably has light diffusing property. Consists of agents. Such a light diffusion layer having adhesiveness can also be referred to as an “adhesive light diffusion layer”.

(6-1) Material of Light Diffusion Layer The light diffusion layer 30 is preferably formed from an adhesive composition containing an adhesive component and light diffusing fine particles (hereinafter referred to as “adhesive composition P”).

  The adhesive component is not particularly limited as long as it exhibits desired adhesiveness in a touch panel or the like, has light transmittance, and does not inhibit the effect of the light diffusing fine particles. Examples of the adhesive component include an acrylic adhesive component, a rubber adhesive component, a silicone adhesive component, a polyurethane adhesive component, and a polyester adhesive component. Among these, an acrylic adhesive component is preferable from the above viewpoint.

  As the acrylic pressure-sensitive adhesive component, those containing the (meth) acrylic acid ester polymer (A) are preferable, and in particular, the (meth) acrylic acid ester polymer (A) cross-linked by the cross-linking agent (B) is preferable. In the present specification, the term “polymer” includes the concept of “copolymer”.

(6-1-1) (Meth) acrylic acid ester polymer (A)
The (meth) acrylic acid ester polymer (A) preferably contains a (meth) acrylic acid alkyl ester having 1 to 20 carbon atoms in the alkyl group as a monomer constituting the polymer. Thereby, the obtained light-diffusion layer 30 can express favorable adhesiveness. The (meth) acrylic acid ester polymer (A) is a monomer having a functional group that reacts with the alkyl group (meth) acrylic acid alkyl ester having 1 to 20 carbon atoms and the crosslinking agent (B) (reactivity). Particularly preferred is a copolymer of a functional group-containing monomer) and other monomers used as desired.

  Examples of the (meth) acrylic acid alkyl ester having 1 to 20 carbon atoms in the alkyl group include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, and (meth) acrylic acid n-. Butyl, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, n-decyl (meth) acrylate, (meth) acrylic acid Examples include n-dodecyl, myristyl (meth) acrylate, palmityl (meth) acrylate, stearyl (meth) acrylate, and the like. Among these, from the viewpoint of further improving the tackiness, (meth) acrylic acid esters having 1 to 8 carbon atoms in the alkyl group are preferred, methyl (meth) acrylate, n-butyl (meth) acrylate and (meth) acrylic. The acid 2-ethylhexyl is particularly preferred. In addition, these may be used independently and may be used in combination of 2 or more type.

  The (meth) acrylic acid ester polymer (A) contains 30 to 95% by mass of a (meth) acrylic acid alkyl ester having 1 to 20 carbon atoms as the monomer unit constituting the polymer. The content is preferably 40 to 90% by mass, and more preferably 50 to 85% by mass.

  As the reactive functional group-containing monomer, a monomer having a hydroxyl group in the molecule (hydroxyl group-containing monomer), a monomer having a carboxyl group in the molecule (carboxyl group-containing monomer), a monomer having an amino group in the molecule (amino group-containing) Monomer) and the like.

  Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, (meth And (meth) acrylic acid hydroxyalkyl esters such as 3-hydroxybutyl acrylate and 4-hydroxybutyl (meth) acrylate. Among them, 2-hydroxyethyl (meth) acrylate is preferred from the viewpoint of the reactivity of the hydroxyl group in the resulting (meth) acrylic acid ester polymer (A) with the crosslinking agent (B) and the copolymerizability with other monomers. Is preferred. These may be used alone or in combination of two or more.

  Examples of the carboxyl group-containing monomer include ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, and citraconic acid. These may be used alone or in combination of two or more.

  Examples of the amino group-containing monomer include aminoethyl (meth) acrylate, n-butylaminoethyl (meth) acrylate, and the like. These may be used alone or in combination of two or more.

  When the (meth) acrylic acid ester polymer (A) contains a reactive functional group-containing monomer as a monomer constituting the polymer, the content is preferably 5 to 35% by mass, particularly 10 It is preferable that it is -30 mass%, Furthermore, it is preferable that it is 20-25 mass%.

  The (meth) acrylic acid ester polymer (A) may contain other monomers as monomer units constituting the polymer, if desired. The other monomer is preferably a monomer that does not contain a reactive functional group. Such other monomers include, for example, (meth) acrylic acid alkoxyalkyl esters such as methoxyethyl (meth) acrylate and ethoxyethyl (meth) acrylate, and aliphatic rings such as cyclohexyl (meth) acrylate (meta ) Acrylic acid ester, (meth) acrylic acid N, N-dimethylaminoethyl, (meth) acrylic acid N, N-dimethylaminopropyl, etc. (meth) acrylic acid ester having acetic acid tertiary amino group, acetic acid Examples include vinyl and styrene. These may be used alone or in combination of two or more.

  The polymerization mode of the (meth) acrylic acid ester polymer (A) may be a random copolymer or a block copolymer.

  The weight average molecular weight of the (meth) acrylic acid ester polymer (A) is preferably 100,000 to 2,000,000, particularly preferably 200,000 to 1,300,000, and more preferably 300,000 to 800,000. preferable. In addition, the weight average molecular weight in this specification is the value of standard polystyrene conversion measured by the gel permeation chromatography (GPC) method.

  In the adhesive composition P, the (meth) acrylic acid ester polymer (A) may be used alone or in combination of two or more.

(6-1-2) Crosslinking agent (B)
When the adhesive component of the adhesive composition P contains a (meth) acrylic acid ester polymer (A) containing a reactive functional group-containing monomer as a monomer unit constituting the polymer, and a crosslinking agent (B), When the adhesive composition P is heated or the like, the crosslinking agent (B) reacts with the reactive functional group of the reactive functional group-containing monomer constituting the (meth) acrylic acid ester polymer (A). Thereby, the structure by which the (meth) acrylic acid ester polymer (A) was bridge | crosslinked with the crosslinking agent (B) is formed, and the intensity | strength and durability of the light-diffusion layer 30 improve.

  The crosslinking agent (B) may be any one that reacts with the reactive functional group of the (meth) acrylic acid ester polymer (A). For example, an isocyanate crosslinking agent, an epoxy crosslinking agent, and an amine crosslinking agent. , Melamine crosslinking agent, aziridine crosslinking agent, hydrazine crosslinking agent, aldehyde crosslinking agent, oxazoline crosslinking agent, metal alkoxide crosslinking agent, metal chelate crosslinking agent, metal salt crosslinking agent, ammonium salt crosslinking agent, etc. Is mentioned. Among these, when the reactive functional group of the (meth) acrylic acid ester polymer (A) is a hydroxyl group, it is preferable to use an isocyanate-based crosslinking agent that is excellent in reactivity with the hydroxyl group, and (meth) acrylic acid When the reactive functional group which the ester polymer (A) has is a carboxyl group, it is preferable to use an epoxy-based crosslinking agent having excellent reactivity with the carboxyl group. In addition, a crosslinking agent (B) can be used individually by 1 type or in combination of 2 or more types.

  The isocyanate-based crosslinking agent contains at least a polyisocyanate compound. Examples of the polyisocyanate compound include aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate and xylylene diisocyanate, aliphatic polyisocyanates such as hexamethylene diisocyanate, alicyclic polyisocyanates such as isophorone diisocyanate and hydrogenated diphenylmethane diisocyanate, etc. , And their biuret bodies, isocyanurate bodies, and adduct bodies that are a reaction product with low molecular active hydrogen-containing compounds such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, and castor oil. Among these, trimethylolpropane-modified aromatic polyisocyanate, particularly trimethylolpropane-modified tolylene diisocyanate and trimethylolpropane-modified xylylene diisocyanate are preferable from the viewpoint of reactivity with hydroxyl groups.

  Examples of the epoxy crosslinking agent include 1,3-bis (N, N′-diglycidylaminomethyl) cyclohexane, N, N, N ′, N′-tetraglycidyl-m-xylylenediamine, ethylene glycol diglycidyl. Examples include ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane diglycidyl ether, diglycidyl aniline, diglycidyl amine and the like.

  It is preferable that content of the crosslinking agent (B) in the adhesive composition P is 0.001-10 mass parts with respect to 100 mass parts of (meth) acrylic acid ester polymer (A), especially 0. It is preferably 0.01 to 5 parts by mass, more preferably 0.02 to 1 part by mass.

(6-1-3) Light Diffusing Fine Particles As the light diffusing fine particles, any material can be used as long as the total haze described above can be in the above range. For example, silica, calcium carbonate, aluminum hydroxide, magnesium hydroxide, Inorganic fine particles such as clay, talc, titanium dioxide; Organic translucent fine particles such as acrylic resin such as polymethyl methacrylate resin, polystyrene resin, polymethyl methacrylate-polystyrene copolymer, polyethylene resin, epoxy resin; Examples thereof include fine particles (for example, Tospearl series manufactured by Momentive Performance Materials Japan) made of a silicon-containing compound having an intermediate structure between inorganic and organic, such as silicone resin. Among these, acrylic resin fine particles, polymethyl methacrylate-polystyrene copolymer fine particles, and fine particles comprising a silicon-containing compound having an intermediate structure between inorganic and organic have excellent dispersibility with respect to the above-mentioned adhesive component and uniform optical properties. Since it is obtained, it is preferable. The above light diffusing fine particles may be used alone or in combination of two or more.

  As the shape of the light diffusing fine particles, spherical fine particles with uniform light diffusion, particularly spherical fine particles are preferable. The average particle diameter of the light diffusing fine particles by the laser diffraction method is preferably 0.1 μm or more, particularly preferably 1 μm or more, and further preferably 2 μm or more. The average particle diameter is preferably 20 μm or less, particularly preferably 10 μm or less, and more preferably 8 μm or less. When the average particle size is within the above range, the total haze value can be easily set to the above-described range without hindering the light transmittance of the light diffusion layer 30.

  In addition, the average particle diameter by the said laser diffraction method is the value measured by the laser diffraction scattering type particle size distribution measuring device using a sample for which 1.2 g of fine particles and 98.8 g of isopropyl alcohol are sufficiently stirred as a measurement sample.

  When the adhesive composition P contains the (meth) acrylate polymer (A) as an adhesive component, the content of the light diffusing fine particles is 100 parts by mass of the (meth) acrylate polymer (A). , Preferably 0.01 parts by mass or more, particularly preferably 0.1 parts by mass or more. Further, the content of the light diffusing fine particles is preferably 15 parts by mass or less, particularly preferably 10 parts by mass or less, and further preferably 5 parts by mass or less. When the content of the light diffusing fine particles is within the above range, the total haze value can be easily set within the above-described range without disturbing the light transmittance of the light diffusing layer 30. Moreover, it becomes easy to fully exhibit adhesiveness with respect to the other member adjacent to the light-diffusion layer 30, and generation | occurrence | production of the malfunction that it peels unnecessarily can be prevented. Even when the adhesive component is other than the acrylic adhesive component, the content of the light diffusing fine particles is preferably within the above range with respect to 100 parts by mass of the adhesive component.

(6-1-4) Various Additives The adhesive composition P is optionally added to various additives such as silane coupling agents, refractive index adjusters, antistatic agents, tackifiers, antioxidants, ultraviolet absorbers. , Light stabilizers, softeners, fillers and the like may be included.

(6-2) Production of Adhesive Composition The adhesive composition P can be produced by mixing an adhesive component, light diffusing fine particles, and, if desired, an additive. When the pressure-sensitive adhesive component contains the (meth) acrylic acid ester polymer (A), the (meth) acrylic acid ester polymer (A) is prepared first, and a crosslinking agent (B) is blended if desired.

  The (meth) acrylic acid ester polymer (A) can be produced by polymerizing a mixture of monomer units constituting the polymer by an ordinary radical polymerization method. The polymerization of the (meth) acrylic acid ester polymer (A) can be performed by a solution polymerization method or the like using a polymerization initiator as desired. Examples of the polymerization solvent include ethyl acetate, n-butyl acetate, isobutyl acetate, toluene, acetone, hexane, methyl ethyl ketone, and the like. Two or more kinds may be used in combination.

  Examples of the polymerization initiator include azo compounds and organic peroxides, and two or more kinds may be used in combination. Examples of the azo compound include 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile), 1,1′-azobis (cyclohexane 1-carbonitrile), 2 , 2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (2,4-dimethyl-4-methoxyvaleronitrile), dimethyl 2,2′-azobis (2-methylpropionate) 4,4′-azobis (4-cyanovaleric acid), 2,2′-azobis (2-hydroxymethylpropionitrile), 2,2′-azobis [2- (2-imidazolin-2-yl) Propane] and the like.

  Examples of organic peroxides include benzoyl peroxide, t-butyl perbenzoate, cumene hydroperoxide, diisopropyl peroxydicarbonate, di-n-propyl peroxydicarbonate, and di (2-ethoxyethyl) peroxy. Examples include dicarbonate, t-butyl peroxyneodecanoate, t-butyl peroxybivalate, (3,5,5-trimethylhexanoyl) peroxide, dipropionyl peroxide, diacetyl peroxide and the like.

  In addition, in the said superposition | polymerization process, the weight average molecular weight of the polymer obtained can be adjusted by mix | blending chain transfer agents, such as 2-mercaptoethanol.

  When the (meth) acrylic acid ester polymer (A) is obtained, the light diffusing fine particles, and optionally the crosslinking agent (B), and additives are added to the solution of the (meth) acrylic acid ester polymer (A). By sufficiently mixing, an adhesive composition P (coating liquid) diluted with a solvent is obtained.

  Examples of the dilution solvent include aliphatic hydrocarbons such as hexane, heptane, and cyclohexane, aromatic hydrocarbons such as toluene and xylene, halogenated hydrocarbons such as methylene chloride and ethylene chloride, methanol, ethanol, propanol, butanol, Alcohols such as 1-methoxy-2-propanol, ketones such as acetone, methyl ethyl ketone, 2-pentanone, isophorone, and cyclohexanone, esters such as ethyl acetate and butyl acetate, and cellosolve solvents such as ethyl cellosolve are used.

  The concentration / viscosity of the coating solution thus prepared is not particularly limited as long as it can be coated, and can be appropriately selected according to the situation. For example, it dilutes so that the density | concentration of the adhesive composition P may be 10-40 mass%. In addition, when obtaining a coating liquid, addition of a dilution solvent etc. is not a necessary condition, and if a viscosity etc. which can be coated with the adhesive composition P are not necessary, it is not necessary to add a dilution solvent.

(6-3) Thickness of the light diffusion layer The thickness of the light diffusion layer 30 (value measured according to JIS K7130) is preferably 5 μm or more, particularly 7.5 μm or more, as a lower limit. And more preferably 10 μm or more. Further, the upper limit is preferably 500 μm or less, more preferably 250 μm or less, particularly preferably 100 μm or less, and further preferably 50 μm or less. When the lower limit value of the thickness of the light diffusion layer 30 is the above, it is possible to achieve both desired adhesiveness and optical characteristics. On the other hand, when the upper limit value of the thickness of the light diffusion layer 30 is the above, it is possible to prevent the obtained touch panel 1A from becoming unnecessarily thick. The light diffusion layer 30 may be formed as a single layer or may be formed by stacking a plurality of layers.

(7) Display body module The display body module 4 in this embodiment is a liquid crystal module which has the structure mentioned above as an example. Display body module 4 or each member constituting display body module 4, that is, first glass substrate 41a, module adhesive layer 42, first polarizing plate 43a, second glass substrate 41b, color filter 44, liquid crystal As the layer 45, the third glass substrate 41c, the second polarizing plate 43b, and the backlight 47, known ones can be used.

  As described above, in the touch panel 1A according to the present embodiment, the distance between the light diffusion layer 30 and the color filter 44 is 4 mm or less. When the display module 4 is used, the distance is the total thickness of the first glass substrate 41a, the module pressure-sensitive adhesive layer 42, the first polarizing plate 43a, and the second glass substrate 41b. The thickness of the 1st glass substrate 41a and the 2nd glass substrate 41b is 0.1-3000 micrometers normally, respectively, Preferably it is 0.3-1500 micrometers. The thickness of the module pressure-sensitive adhesive layer 42 is usually 1 to 1000 μm, preferably 5 to 750 μm. The thickness of the 1st polarizing plate 43a is 1-1000 micrometers normally, Preferably it is 3-750 micrometers. The thickness of each member is appropriately selected so that the distance between the light diffusion layer 30 and the color filter 44 is 4 mm or less.

3. Touch Panel Manufacturing Method The touch panel 1A according to the present embodiment can be manufactured by a conventional method, but an example of a preferable manufacturing method will be described.

(1) Formation of writing quality improving layer The writing quality improving layer 10 is formed on the base film 21. Specifically, a coating composition for the writing quality improving layer 10, preferably coating composition C, and a coating solution containing a solvent as required are applied to the base film 21 and cured to improve the writing quality. Layer 10 is formed.

  The solvent can be used for improving coating properties, adjusting the viscosity, adjusting the solid content concentration, etc., and can be used without particular limitation as long as the curable components are dissolved and the fine particles are dispersed. .

  Specific examples of the solvent include alcohols such as methanol, ethanol, isopropanol, butanol and octanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; esters such as ethyl acetate, butyl acetate, ethyl lactate and γ-butyrolactone Ethers such as ethylene glycol monomethyl ether (methyl cellosorb), ethylene glycol monoethyl ether (ethyl cellosorb), diethylene glycol monobutyl ether (butyl cellosorb), propylene glycol monomethyl ether; aromatic hydrocarbons such as benzene, toluene and xylene; dimethylformamide Amides such as dimethylacetamide and N-methylpyrrolidone.

  Application of the coating solution of the coating composition may be performed by a conventional method, for example, a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, or a gravure coating method. When the coating composition coating liquid is applied, the coating film is preferably dried at 40 to 120 ° C. for about 30 seconds to 5 minutes.

When the coating composition is active energy ray curable like the coating composition C, the coating composition is cured by irradiating the coating film of the coating composition with active energy rays such as ultraviolet rays and electron beams. . UV irradiation, high-pressure mercury lamp, a fusion H lamp, can be carried out by a xenon lamp or the like, the dose of ultraviolet ray is illuminance 50~1000mW / cm ^2, about the amount of light 50~1000mJ / cm ² is preferred. On the other hand, the electron beam irradiation can be performed by an electron beam accelerator or the like, and the irradiation amount of the electron beam is preferably about 10 to 1000 krad.

(2) Formation of light diffusing layer The light diffusing layer 30 is preferably formed on a release surface (a surface having releasability) of the release sheet to form a light diffusion layer sheet. The light diffusion layer 30 in the present embodiment is preferably formed from the adhesive composition P. Therefore, preferably, the coating liquid containing the adhesive composition P and, if desired, a solvent is applied to the release surface of the release sheet, and heat treatment is performed to form an application layer. When a curing period is required, a curing period is provided. When the curing period is not necessary, the coating layer becomes the light diffusion layer 30 as it is, and a light diffusion layer sheet is obtained. In addition, the said heat processing can also serve as the drying process at the time of volatilizing the solvent of the adhesive composition P, etc.

  When the adhesive composition P contains the (meth) acrylic acid ester polymer (A), the heating temperature of the heat treatment is preferably 50 to 150 ° C, particularly preferably 70 to 120 ° C. . The heating time is preferably 30 seconds to 10 minutes, particularly preferably 50 seconds to 2 minutes. After the heat treatment, if necessary, a curing period of about 1 to 2 weeks may be provided at room temperature (for example, 23 ° C., 50% RH). When this curing period is necessary, after the curing period has elapsed, when the curing period is unnecessary, the light diffusion layer 30 is formed after the heat treatment is completed.

  In addition, the application method of the coating liquid containing the solvent mixed with the adhesive composition P and the adhesive composition P is the same as the application method of the solvent and the coating liquid of the coating composition for the writing quality improving layer 10.

(3) Formation of pressure-sensitive adhesive layer The first pressure-sensitive adhesive layer 22a, the second pressure-sensitive adhesive layer 22b, and the third pressure-sensitive adhesive layer 22c are preferably formed on the release surface of the release sheet to form an adhesive sheet. For example, a coating solution containing a pressure-sensitive adhesive composition for each pressure-sensitive adhesive layer and, if desired, a solvent is applied to the release surface of the release sheet and dried to form a pressure-sensitive adhesive layer to obtain a pressure-sensitive adhesive sheet.

(4) Lamination of each member Lamination | stacking of each member may be performed manually using a press roller, and may be automatically performed using a laminator apparatus. The order in which the members are stacked is not particularly limited, and the method described below is merely an example.

  First, the first pressure-sensitive adhesive layer 22a in the pressure-sensitive adhesive sheet of the first pressure-sensitive adhesive layer 22a is opposite to the writing quality improving layer 10 side in the base film 21 on which the writing quality improving layer 10 is formed. Laminate on the surface. Then, the release sheet is peeled off, and the exposed first pressure-sensitive adhesive layer 22 a is bonded to the cover material 23.

  On the other hand, the 3rd adhesive layer 22c in the adhesive sheet of the 3rd adhesive layer 22c is laminated | stacked on the 1st touch sensor 24a. And the peeling sheet of the adhesive sheet of the 3rd adhesive layer 22c is peeled, and the exposed 3rd adhesive layer 22c is bonded to the 2nd touch sensor 24b. Subsequently, the 2nd adhesive layer 22b in the adhesive sheet of the 2nd adhesive layer 22b is bonded to the surface on the opposite side to the 3rd adhesive layer 22c side in the 1st touch sensor 24a. Further, the light diffusion layer 30 of the light diffusion layer sheet is bonded to the surface opposite to the third pressure-sensitive adhesive layer 22c side in the second touch sensor 24b.

  Next, the release sheet is peeled from the adhesive sheet of the second adhesive layer 22b, and the exposed second adhesive layer 22b is bonded to the opposite side of the cover material 23 from the first adhesive layer 22a side. To do. Finally, the release sheet is peeled from the light diffusion layer sheet, and the exposed light diffusion layer 30 is bonded to the first glass substrate 41 a of the display module 4. Thereby, the touch panel 1A shown in FIG. 1 is manufactured.

  The touch panel 1A described above is excellent in writing with a touch pen, is less glaring, and has good visibility of a display image.

[Second Embodiment]
In the touch panel 1A according to the first embodiment described above, the light diffusion layer 30 is provided at a position adjacent to the display body module 4, but the present invention is not limited to this, and the writing quality improving layer is not limited thereto. 10 and the display module 4 may be provided at an arbitrary position.

  For example, the light diffusion layer 30 may be provided between the base film 21 and the cover material 23 as in the touch panel 1B according to the second embodiment shown in FIG. In this case, in the touch panel 1A according to the first embodiment, the first pressure-sensitive adhesive layer 22a is replaced with the light diffusion layer 30, and the fourth pressure-sensitive adhesive layer 22d is provided at the position where the light diffusion layer 30 was present. Will be provided. The fourth pressure-sensitive adhesive layer 22d can have the same configuration as the first pressure-sensitive adhesive layer 22a, the second pressure-sensitive adhesive layer 22b, or the third pressure-sensitive adhesive layer 22c described above.

  Here, also in the touch panel 1B according to the present embodiment, the total haze from the writing quality improving layer 10 to the light diffusion layer 30 (in this embodiment, the total of the writing quality improving layer 10, the base film 21 and the light diffusion layer 30). Haze) is 12% or more and 45% or less, and the distance between the light diffusion layer 30 and the color filter 44 needs to be 4 mm or less.

  It is preferable that the light diffusion layer 30 in the touch panel 1B according to the present embodiment basically has the same configuration as the light diffusion layer 30 of the touch panel 1A according to the first embodiment. However, the light diffusing fine particles in the adhesive composition P are preferably light diffusing fine particles made of a silicon-containing compound having an intermediate structure between organic and inorganic, such as a silicone resin. Further, the content of the light diffusing fine particles in the adhesive composition P is preferably 0.01 parts by mass or more with respect to 100 parts by mass of the (meth) acrylic ester polymer (A). The amount is preferably 1 part by mass or more, and more preferably 0.5 part by mass or more. The content of the light diffusing fine particles is preferably 15 parts by mass or less, particularly preferably 12 parts by mass or less, and further preferably 10 parts by mass or less. When the content of the light diffusing fine particles is within the above range, the total haze value can be easily set within the above-described range without disturbing the light transmittance of the light diffusing layer 30. Moreover, it becomes easy to fully exhibit adhesiveness with respect to the other member adjacent to the light-diffusion layer 30, and generation | occurrence | production of the malfunction that it peels carelessly can be prevented.

  The touch panel 1B according to the present embodiment can be manufactured basically in the same manner as the touch panel 1A according to the first embodiment. Lamination | stacking to the base film 21 of the light-diffusion layer 30 can be performed using a light-diffusion layer sheet | seat similarly to the touchscreen 1A which concerns on 1st Embodiment.

  Further, the position of the light diffusion layer 30 in the touch panel is not limited to the position in the touch panel 1A according to the first embodiment and the touch panel 1B according to the second embodiment. For example, the second adhesive layer 22b or the third adhesive layer 22c in the touch panel 1A according to the first embodiment may be replaced with a light diffusion layer. In this case, the light diffusion layer 30 in the touch panel 1A according to the first embodiment can be the same adhesive layer as the first to third adhesive layers 22a to 22c.

  Further, for example, the light diffusion layer 30 may be provided between the writing quality improving layer 10 and the base film 21 so as to be adjacent to the writing quality improving layer 10. Such a touch panel can be manufactured basically in the same manner as the touch panel 1 </ b> A according to the first embodiment, but after the light diffusion layer 30 is laminated on the base film 21, the light diffusion layer 30 is written on the light diffusion layer 30. The point which forms the taste improvement layer 10 differs. Lamination | stacking to the base film 21 of the light-diffusion layer 30 can be performed using a light-diffusion layer sheet | seat similarly to the touchscreen 1A which concerns on 1st Embodiment. When the light diffusion layer 30 is provided between the writing quality improving layer 10 and the base film 21, the light diffusion layer 30 may not have adhesiveness. In this case, for example, the light diffusion layer 30 is formed using a coating composition containing a curable component such as an active energy ray-curable component and a thermosetting component and fine particles, like the writing quality improving layer 10. May be.

[Third Embodiment]
In the touch panel 1 </ b> A according to the first embodiment described above, the position detection function is performed by the first touch sensor 24 a and the second touch sensor 24 b that exist outside the display body module 4. However, the display module may have a position detection function.

  For example, like the touch panel 1C according to the third embodiment shown in FIG. 3, the writing quality improving layer 10 is located on the side where the touch pen of the writing quality improving layer 10 is not in contact (the lower side in FIG. 3). A base film 21 on which the taste improving layer 10 is formed, an adhesive layer 22 for pasting the base film 21, and a cover material 23 on which the base film 21 is pasted via the adhesive layer 22 And a light diffusion layer 30 having adhesive properties for bonding the cover material 23, and a display module 5 having a position detection function, to which the cover material 23 is bonded via the light diffusion layer 30. It may be configured.

  The display module 5 is not particularly limited as long as it has a color filter and a position detection function (touch sensor). Usually, a liquid crystal (LCD) module, a light emitting diode (LED) module, an organic electroluminescence (organic) EL) module or the like is used. FIG. 3 shows a liquid crystal module as an example. The display module 5 in the present embodiment includes a first glass substrate 51a adjacent to the light diffusion layer 30, a first module adhesive layer 52a located below the first glass substrate 51a, and a first A first polarizing plate 53a positioned below the module adhesive layer 52a, a second glass substrate 51b positioned below the first polarizing plate 53a, and a lower side of the second glass substrate 51b. The color filter 54 positioned, the liquid crystal layer 55 positioned below the color filter 54, the second module adhesive layer 52b positioned below the liquid crystal layer 55, and the second module adhesive layer 52b. The first touch sensor 56a located on the side, the third module adhesive layer 52c located on the lower side of the first touch sensor 56a, and the second located on the lower side of the third module adhesive layer 52c. No H sensor 56b, a fourth module adhesive layer 52d located below the second touch sensor 56b, a third glass substrate 51c located below the fourth module adhesive layer 52d, and a third The second polarizing plate 53b located on the lower side of the glass substrate 51c and the backlight 57 located on the lower side of the second polarizing plate 53b.

  The touch panel 1C according to the present embodiment can be manufactured basically in the same manner as the touch panel 1A according to the first embodiment.

[Fourth Embodiment]
In the touch panel 1C according to the third embodiment described above, the light diffusion layer 30 is provided at a position adjacent to the display body module 5, but the present invention is not limited to this, and the writing quality improving layer. 10 and the display module 5 may be provided at an arbitrary position.

  For example, the light diffusion layer 30 may be provided between the base film 21 and the cover material 23 as in the touch panel 1D according to the fourth embodiment shown in FIG. In this case, in the touch panel 1 </ b> C according to the third embodiment, the pressure-sensitive adhesive layer 22 is replaced with the light diffusion layer 30, and the light diffusion layer 30 is replaced with the pressure-sensitive adhesive layer 22. The pressure-sensitive adhesive layer 22 can have the same configuration as the pressure-sensitive adhesive layer 22 of the touch panel 1C according to the third embodiment.

  The touch panel 1D according to the present embodiment can be manufactured basically in the same manner as the touch panel 1B according to the second embodiment.

[Fifth Embodiment]
In the touch panels 1 </ b> A to 1 </ b> D according to the first to fourth embodiments described above, there is only one cover material 23, but in order to adjust the distance between the light diffusion layer 30 and the color filter 54, or to improve the writing quality. In order to adjust the total haze from the enhancement layer 10 to the light diffusion layer 30, a plurality of cover materials (and adhesive layers) may be provided. For example, like the fifth touch panel 1E shown in FIG. 5, two cover materials and two adhesive layers may be provided. Specifically, the fifth touch panel 1E is located on the side (the lower side in FIG. 5) where the writing quality improving layer 10 and the touch pen of the writing quality improving layer 10 do not contact, and the writing quality improving layer 10 is formed. A base film 21, an adhesive light diffusion layer 30 located below the base film 21, and a first cover material 23 a on which the base film 21 is bonded via the light diffusion layer 30. A first pressure-sensitive adhesive layer 22a positioned below the first cover material 23a, a second cover material 23b positioned below the first pressure-sensitive adhesive layer 22a, and a second cover material 23b A second pressure-sensitive adhesive layer 22b located on the lower side, and a display module 5 having a position detection function, to which a second cover material 23b is bonded via the second pressure-sensitive adhesive layer 22b. It is configured. The first cover material 23a may have a step due to a printed layer or the like like the cover material 23 described above. On the other hand, a cover material other than the first cover material 23a (in this embodiment, the second cover material 23b) usually does not have a step due to a printed layer or the like. The fifth touch panel 1E is a modified example based on the fourth touch panel 1D, but is not limited thereto.

  Further, the position of the light diffusion layer 30 in the touch panel is not limited to the position in the touch panel 1E according to the fifth embodiment. For example, in the touch panel 1E according to the fifth embodiment, the first pressure-sensitive adhesive layer 22a or the second pressure-sensitive adhesive layer 22b is replaced with the light diffusion layer 30, and the light diffusion layer 30 is replaced with the first pressure-sensitive adhesive layer 22a or the second pressure-sensitive adhesive layer 22a. The same adhesive layer as the adhesive layer 22b may be replaced.

  Further, the number of the cover material and the pressure-sensitive adhesive layer is not particularly limited as long as the distance between the light diffusion layer 30 and the color filter 54 and the total haze from the writing taste improving layer 10 to the light diffusion layer 30 are within a predetermined range. . For example, three cover materials and three pressure-sensitive adhesive layers may be provided as in a sixth touch panel 1F shown in FIG.

  The embodiment described above is described for facilitating understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

  For example, when the surface of the base film 21 satisfies the above-described writing taste properties, the writing quality improving layer 10 as a coat layer is not necessarily required. In this case, the base film 21 itself is a writing quality improving layer. Become.

  EXAMPLES Hereinafter, although an Example etc. demonstrate this invention further more concretely, the scope of the present invention is not limited to these Examples etc.

[Example 1]
(1) Formation of writing quality improving layer 100 parts by weight of organic / inorganic hybrid resin (manufactured by Arakawa Chemical Industry Co., Ltd., product name “OPSTAR Z7530”) as a curable component. And 10 parts by mass of true spherical crosslinked polymethyl methacrylate fine particles having an average particle size of 3 μm and 5 parts by mass of 1-hydroxycyclohexyl phenyl ketone as a photopolymerization initiator were mixed to obtain a coating composition. . The coating composition was diluted with propylene glycol monomethyl ether to prepare a coating solution.

The coating solution obtained above is applied to the surface of the easy-adhesion layer side of a polyester film with an easy-adhesion layer (product of Toyobo Co., Ltd., product name “Cosmo Shine A4300”, thickness: 125 μm) as a base film. And dried at 70 ° C. for 1 minute. Next, in the atmosphere, ultraviolet rays were irradiated under the following conditions by an ultraviolet irradiation device (manufactured by GS Yuasa Corporation, product name “Nitrogen purged small conveyor type UV irradiation device CSN2-40”), and the writing quality was 5 μm thick. The improvement layer was formed and the laminated body which consists of a writing taste improvement layer and a base film was obtained.
[UV irradiation conditions]
・ Light source: High pressure mercury lamp ・ Lamp power: 1.4 kW
・ Conveyor speed: 1.2m / min
Illuminance: 100 mW / cm ²
・ Light intensity: 240 mJ / cm ²

  About the thickness of a writing quality improvement layer, the total thickness of the said laminated body is measured using a constant-pressure thickness measuring device (the product name "PG-01J" by the Teclock company), and the total thickness of the obtained laminated body And the difference with the thickness of the said base film was computed as the thickness of a writing quality improvement layer.

(2) Formation of light diffusion layer 60 parts by mass of n-butyl acrylate, 20 parts by mass of methyl acrylate, and 20 parts by mass of 2-hydroxyethyl acrylate were copolymerized by a solution polymerization method to obtain an acrylate ester copolymer. Prepared. When the molecular weight of this acrylate copolymer was measured by the following method, the weight average molecular weight (Mw) was 500,000.

The said weight average molecular weight (Mw) is a weight average molecular weight of polystyrene conversion measured on the following conditions (GPC measurement) using the gel permeation chromatography (GPC).
<Measurement conditions>
GPC measurement device: manufactured by Tosoh Corporation, HLC-8020
GPC column (passed in the following order): TSK guard column HXL-H manufactured by Tosoh Corporation
TSK gel GMHXL (× 2)
TSK gel G2000HXL
・ Measurement solvent: Tetrahydrofuran ・ Measurement temperature: 40 ° C.

  100 parts by mass of the acrylic ester copolymer obtained in the above process, 0.25 parts by mass of trimethylolpropane-modified tolylene diisocyanate (product name “BHS-8515” manufactured by Toyochem Co., Ltd.) as a crosslinking agent, and average Spherical silicone fine particles with a particle size of 2.0 μm (fine particles made of silicon-containing compound having an intermediate structure between inorganic and organic) (product name “Tospearl 120” manufactured by Momentive Performance Materials Japan) 0.5 The coating solution of the adhesive composition was obtained by mixing with a mass part and diluting with ethyl acetate.

  The coating liquid of the pressure-sensitive adhesive composition obtained above was subjected to a knife on the release treatment surface of a release sheet (SP-PET3811, thickness: 38 μm, manufactured by Lintec Co., Ltd.) obtained by releasing one side of a polyethylene terephthalate film with a silicone release agent. After coating with a coater, heat treatment was performed at 90 ° C. for 1 minute to form a light diffusion layer having a thickness of 10 μm to obtain a light diffusion layer sheet.

  Regarding the thickness of the light diffusion layer, the total thickness of the light diffusion layer sheet was measured using a constant pressure thickness measuring instrument (product name “PG-01J” manufactured by Teclock Co., Ltd.), and the obtained light diffusion layer sheet The difference between the total thickness and the thickness of the release sheet was calculated as the thickness of the light diffusion layer.

(3) Formation of pressure-sensitive adhesive layer 100 parts by mass of the acrylate copolymer used in the light diffusion layer and trimethylolpropane-modified tolylene diisocyanate (product name “BHS-8515” manufactured by Toyochem Co., Ltd.) as a crosslinking agent ) 0.25 part by mass was mixed and diluted with ethyl acetate to obtain a coating solution of the adhesive composition.

  The coating liquid of the pressure-sensitive adhesive composition obtained above was subjected to a knife on the release treatment surface of a release sheet (SP-PET3811, thickness: 38 μm, manufactured by Lintec Co., Ltd.) obtained by releasing one side of a polyethylene terephthalate film with a silicone release agent. After coating with a coater, heat treatment was performed at 90 ° C. for 1 minute to form a pressure-sensitive adhesive layer having a thickness of 100 μm to obtain a pressure-sensitive adhesive sheet.

  Regarding the thickness of the pressure-sensitive adhesive layer, the total thickness of the pressure-sensitive adhesive sheet was measured using a constant pressure thickness measuring instrument (product name “PG-01J” manufactured by Teclock Co., Ltd.). The difference from the thickness of the release sheet was calculated as the thickness of the pressure-sensitive adhesive layer.

(4) Lamination | stacking of each member Each member was laminated | stacked as shown below, and the touchscreen which has the structure (configuration 1E) shown in FIG. 5 was manufactured. Lamination of each member was performed manually using a pressure roller (2 kg, material of sample contact portion: rubber).

(A) First, a base film in a laminate composed of a writing quality improving layer and a base film and a light diffusion layer of a light diffusion layer sheet were laminated.
(B) Next, the release sheet of the light diffusion layer sheet is peeled from the light diffusion layer, and the exposed light diffusion layer and the first cover material (product name “Eagle XG”, thickness 700 μm, manufactured by Corning) Were laminated.
(C) Next, the first cover material and an adhesive layer (thickness: 100 μm) of the adhesive sheet were laminated. This pressure-sensitive adhesive layer corresponds to the first pressure-sensitive adhesive layer 22a in FIG.
(D) Next, the release sheet of the pressure-sensitive adhesive sheet is peeled from the pressure-sensitive adhesive layer (first pressure-sensitive adhesive layer 22a), and the exposed pressure-sensitive adhesive layer (first pressure-sensitive adhesive layer 22a) and the second cover material ( Corning, product name “Eagle XG”, thickness 1100 μm) was laminated.
(E) Next, the second cover material and an adhesive layer (thickness: 100 μm) of the adhesive sheet were laminated. This pressure-sensitive adhesive layer corresponds to the second pressure-sensitive adhesive layer 22b in FIG.
(F) Finally, the release sheet of the pressure-sensitive adhesive sheet is peeled off from the pressure-sensitive adhesive layer (second pressure-sensitive adhesive layer 22b) and displayed from the exposed pressure-sensitive adhesive layer (second pressure-sensitive adhesive layer 22b) and the color filter. A display module (resolution: 264 ppi) having a distance of 1 mm to the surface of the body module was laminated to obtain a touch panel having the configuration shown in FIG. 5 (configuration 1E).

[Example 2]
The material, blending ratio and thickness of the writing quality improving layer and light diffusion layer are changed as shown in Table 1, and the thickness of the first cover material is changed to 1100 μm, which corresponds to the first pressure-sensitive adhesive layer 22a. A touch panel was produced in the same manner as in Example 1 except that the thickness of the pressure-sensitive adhesive layer and the thickness of the pressure-sensitive adhesive layer corresponding to the second pressure-sensitive adhesive layer 22b were each changed to 400 μm.

[Examples 3 and 4]
A touch panel was produced in the same manner as in Example 1 except that the material, blending ratio, and thickness of the writing quality improving layer and the light diffusion layer were changed as shown in Table 1.

Example 5
While changing the material, compounding ratio, and thickness of the writing quality improving layer and the light diffusion layer as shown in Table 1, the configuration of the touch panel is changed to the configuration (configuration 1D) shown in FIG. 4, and the thickness of the adhesive layer is changed. A touch panel was produced in the same manner as in Example 1 except that the thickness was changed to 300 μm. The touch panel having the configuration shown in FIG. 4 was manufactured as follows.

(A) First, a base film in a laminate composed of a writing quality improving layer and a base film and a light diffusion layer of a light diffusion layer sheet were laminated.
(B) Next, the release sheet of the light diffusion layer sheet was peeled off from the light diffusion layer, and the exposed light diffusion layer and a cover material (product name “Eagle XG”, thickness 700 μm, manufactured by Corning) were laminated. .
(C) Next, the cover material and an adhesive layer (thickness 300 μm) of the adhesive sheet were laminated.
(D) Finally, the release sheet of the pressure-sensitive adhesive sheet is peeled from the pressure-sensitive adhesive layer, and the distance between the exposed pressure-sensitive adhesive layer and the color filter to the surface of the display module is 1 mm (resolution: 264 ppi) And a touch panel having the configuration (configuration 1D) shown in FIG. 4 was obtained.

Example 6
A touch panel was produced in the same manner as in Example 5 except that the material, blending ratio and thickness of the writing quality improving layer and the light diffusion layer were changed as shown in Table 1.

[Comparative Example 1]
A touch panel was produced in the same manner as in Example 1 except that the material, blending ratio, and thickness of the writing quality improving layer and the light diffusion layer were changed as shown in Table 1.

[Comparative Example 2]
A touch panel was produced in the same manner as in Example 5 except that the material, blending ratio and thickness of the writing quality improving layer and the light diffusion layer were changed as shown in Table 1.

[Comparative Example 3]
While changing the material, blending ratio, and thickness of the writing quality improving layer and the light diffusion layer as shown in Table 1, the configuration of the touch panel is changed to the configuration (configuration 1F) shown in FIG. A touch panel was produced in the same manner as in Example 1 except that the thickness was changed to 1100 μm and the thickness of the pressure-sensitive adhesive layer was changed to 300 μm and 200 μm.

  Here, the touch panel 1F shown in FIG. 6 is located on the side (the lower side in FIG. 6) where the writing quality improving layer 10 and the touch pen of the writing quality improving layer 10 do not contact, and the writing quality improving layer 10 is formed. The base film 21, the light diffusion layer 30 having adhesiveness located under the base film 21, and the first cover material on which the base film 21 is bonded via the light diffusion layer 30 23a (thickness: 1100 μm), a first adhesive layer 22a (thickness: 300 μm) located below the first cover material 23a, and a first adhesive layer 22a located below the first adhesive layer 22a 2 cover material 23b (thickness: 1100 μm), second adhesive layer 22b (thickness: 200 μm) located below the second cover material 23b, and lower side of the second adhesive layer 22b A third cover material 23c (thickness: 1100 μm) located in the A position detection function in which a third adhesive layer 22c (thickness: 200 μm) located on the lower side of the cover material 23c and the third cover material 23c are bonded via the third adhesive layer 22c. The display body module 5 is provided.

The touch panel 1F having the configuration shown in FIG. 6 was manufactured as follows.
(A) First, a base film in a laminate composed of a writing quality improving layer and a base film and a light diffusion layer of a light diffusion layer sheet were laminated.
(B) Next, the release sheet of the light diffusion layer sheet is peeled from the light diffusion layer, and the exposed light diffusion layer and the first cover material (Corning, product name “Eagle XG”, thickness 1100 μm) Were laminated.
(C) Next, the first cover material and the pressure-sensitive adhesive layer (thickness 300 μm) of the pressure-sensitive adhesive sheet were laminated. This pressure-sensitive adhesive layer corresponds to the first pressure-sensitive adhesive layer 22a in FIG.
(D) Next, the release sheet of the pressure-sensitive adhesive sheet is peeled from the pressure-sensitive adhesive layer (first pressure-sensitive adhesive layer 22a), and the exposed pressure-sensitive adhesive layer (first pressure-sensitive adhesive layer 22a) and the second cover material ( Corning, product name “Eagle XG”, thickness 1100 μm) was laminated.
(E) Next, the second cover material and an adhesive layer (thickness: 200 μm) of the adhesive sheet were laminated. This pressure-sensitive adhesive layer corresponds to the second pressure-sensitive adhesive layer 22b in FIG.
(F) Next, the release sheet of the pressure-sensitive adhesive sheet is peeled from the pressure-sensitive adhesive layer (second pressure-sensitive adhesive layer 22b), and the exposed pressure-sensitive adhesive layer (second pressure-sensitive adhesive layer 22b) and the third cover material ( Corning, product name “Eagle XG”, thickness 1100 μm) was laminated.
(G) Next, the third cover material and an adhesive layer (thickness: 200 μm) of the adhesive sheet were laminated. This pressure-sensitive adhesive layer corresponds to the third pressure-sensitive adhesive layer 22c in FIG.
(H) Finally, the release sheet of the pressure-sensitive adhesive sheet is peeled off from the pressure-sensitive adhesive layer (third pressure-sensitive adhesive layer 22c) and displayed from the exposed pressure-sensitive adhesive layer (third pressure-sensitive adhesive layer 22c) and the color filter. A display module (resolution: 264 ppi) having a distance of 1 mm to the surface of the body module was laminated to obtain a touch panel having the configuration shown in FIG. 6 (configuration 1F).

[Comparative Example 4]
The light diffusion layer used in Example 1 is changed to the pressure-sensitive adhesive layer (thickness 10 μm) used in Example 1, and the configuration of the touch panel is changed to the configuration shown in FIG. 7 (Configuration 1G). A touch panel was produced in the same manner.

  The touch panel 1G shown in FIG. 7 is located on the side (the lower side in FIG. 7) where the writing quality improving layer 10 and the touch pen of the writing quality improving layer 10 do not contact, and the writing quality improving layer 10 is formed. The base film 21, the first pressure-sensitive adhesive layer 22 a (thickness: 10 μm) located below the base film 21, and the first cover material located below the first pressure-sensitive adhesive layer 22 a 23a, a second pressure-sensitive adhesive layer 22b (thickness: 100 μm) located below the first cover material 23a, and a second cover material 23b located below the second pressure-sensitive adhesive layer 22b, The second cover material 23b was bonded via the third adhesive layer 22c (thickness: 100 μm) located below the second cover material 23b and the third adhesive layer 22c. And a display module 5 having a position detection function.

The touch panel 1G having the configuration shown in FIG. 7 was manufactured as follows.
(A) First, a base film in a laminate composed of a writing quality improving layer and a base film and an adhesive layer (thickness 10 μm) of the adhesive sheet were laminated. This pressure-sensitive adhesive layer corresponds to the first pressure-sensitive adhesive layer 22a in FIG.
(B) Next, the release sheet of the pressure-sensitive adhesive sheet is peeled off from the pressure-sensitive adhesive layer (first pressure-sensitive adhesive layer 22a), and the exposed pressure-sensitive adhesive layer (first pressure-sensitive adhesive layer 22a) and the first cover material ( Corning, product name “Eagle XG”, thickness 700 μm) was laminated.
(C) Next, the first cover material and an adhesive layer (thickness: 100 μm) of the adhesive sheet were laminated. This pressure-sensitive adhesive layer corresponds to the second pressure-sensitive adhesive layer 22b in FIG.
(D) Next, the release sheet of the pressure-sensitive adhesive sheet is peeled from the pressure-sensitive adhesive layer (second pressure-sensitive adhesive layer 22b), and the exposed pressure-sensitive adhesive layer (second pressure-sensitive adhesive layer 22b) and the second cover material ( Corning, product name “Eagle XG”, thickness 1100 μm) was laminated.
(E) Next, the second cover material and an adhesive layer (thickness: 100 μm) of the adhesive sheet were laminated. This pressure-sensitive adhesive layer corresponds to the third pressure-sensitive adhesive layer 22c in FIG.
(F) Finally, the release sheet of the pressure-sensitive adhesive sheet is peeled off from the pressure-sensitive adhesive layer (third pressure-sensitive adhesive layer 22c) and displayed from the exposed pressure-sensitive adhesive layer (third pressure-sensitive adhesive layer 22c) and the color filter. A display module (resolution: 264 ppi) having a distance of 1 mm to the body module surface was laminated to obtain a touch panel having the configuration (configuration 1G) shown in FIG.

[Reference Example 1]
A touch panel was produced in the same manner as in Example 1 except that the material, blending ratio, and thickness of the writing quality improving layer and the light diffusion layer were changed as shown in Table 1.

Here, details of the abbreviations and the like described in Table 1 are as follows.
A: Organic-inorganic hybrid resin (Arakawa Chemical Industries, product name “OPSTAR Z7530”)
B: Multifunctional urethane acrylate (Arakawa Chemical Industries, product name “Beam Set 575CB”)
C: True spherical crosslinked polymethyl methacrylate fine particles having an average particle diameter of 3 μm (CV value: 32%)
D: Amorphous silica fine particles having an average particle diameter of 4.5 μm (CV value: 35%)
E: Amorphous silica fine particles having an average particle diameter of 1.5 μm (CV value: 88%)
F: True spherical crosslinked polymethyl methacrylate fine particles having an average particle diameter of 1.5 μm (CV value: 23%)
G: 1-hydroxycyclohexyl phenyl ketone (photopolymerization initiator)
H: Acrylate ester copolymer (Mw: 500,000) obtained by copolymerizing 60 parts by mass of n-butyl acrylate, 20 parts by mass of methyl acrylate and 20 parts by mass of 2-hydroxyethyl acrylate by a solution polymerization method )
I: True spherical silicone fine particles having an average particle size of 2.0 μm (fine particles made of a silicon-containing compound having an intermediate structure between inorganic and organic) (product name “Tospearl 120” manufactured by Momentive Performance Materials Japan)
J: True spherical polymethyl methacrylate-polystyrene copolymer fine particles having an average particle size of 3.5 μm K: Trimethylolpropane modified tolylene diisocyanate (product name “BHS-8515” manufactured by Toyochem Co.) (crosslinking agent)

[Test Example 1] (Calculation of distance between light diffusion layer and color filter)
In the touch panels manufactured in Examples and Comparative Examples, the distance between the light diffusion layer and the color filter was calculated. As described above, in the display module (resolution: 264 ppi) used in Examples and Comparative Examples, the distance from the color filter to the surface of the display module (the surface on which the adhesive layer is attached) was 1 mm. . The results are shown in Table 2.

[Test Example 2] (Measurement of haze value)
The total haze (%) and internal haze (%) from the writing quality improving layer to the light diffusing layer in the touch panels produced in the examples and comparative examples were determined using a haze meter (product name “NDH2000” manufactured by Nippon Denshoku Industries Co., Ltd.). Was measured according to JIS K7105. The results are shown in Table 2.

  Specifically, the haze of the laminate of the writing quality improving layer, the base film, the light diffusion layer (the pressure-sensitive adhesive layer in Comparative Example 4) and the release sheet obtained during the production in Examples and Comparative Examples was measured. The total haze was calculated by subtracting the haze of the release sheet from the haze.

  Further, the pressure-sensitive adhesive sheet (pressure-sensitive adhesive layer + release sheet) used in Examples and Comparative Examples was pasted on the writing quality improving layer of the laminate, and the haze including the pressure-sensitive adhesive sheet was measured. And the internal haze was computed by deducting the haze of an adhesive sheet and the haze of a peeling sheet from the said haze.

[Test Example 3] (Pen sliding test)
The touch panels manufactured in Examples and Comparative Examples were placed on a glass substrate with the writing quality improving layer side up. The pen tip of a hard felt core touch pen (product name "ACK-2003" manufactured by Wacom Co., Ltd.) with a nib diameter of 0.5 mm is vertically applied to the surface of the writing quality improving layer under a pressure of 3.92 N. It was moved at a speed of 100 mm / min in an arbitrary direction parallel to the surface of the writing quality improving layer while being in contact with (the direction in which the axis of the nib is perpendicular to the surface of the writing quality improving layer). In addition, the said touch pen was attached to the measurement trolley | bogie, and the said stylus was made to slide on the writing improvement layer by moving the said trolley | bogie.

  The nib resistance at the time of movement was measured using a universal testing machine (product name “Tensilon” manufactured by Orientec Co., Ltd.) to obtain a chart of moving distance (mm) −nib resistance (mN). Then, the obtained moving distance (mm) -pen tip resistance force (mN) chart is Fourier-transformed by software (product name “Excel” manufactured by Microsoft Corporation), and a frequency (Hz) -amplitude (−) chart. Got. From the frequency (Hz) -amplitude (-) chart, the average value, maximum value (maximum amplitude value), and number of peaks (amplitude number) of the amplitude in the frequency range of 1 to 2 Hz were obtained. The results are shown in Table 2.

[Test Example 4] (Sensory evaluation of writing taste)
The touch panels manufactured in Examples and Comparative Examples were placed on a glass substrate with the writing quality improving layer side up. The panel touches and slides the pen tip of a hard felt core touch pen (manufactured by Wacom Corp., product name “ACK-2003”) with a pen tip diameter of 0.5 mm on the surface of the writing quality improving layer. evaluated.

  In the evaluation, a writing pressure of about 400 g using a pencil (Mitsubishi Pencil Co., Ltd., product name “Mitsubishi Pencil Uni B”) on five layers of paper (manufactured by KOKUYO S & T, product name “Campus Note A Rule No-201A”). Those that were close to the writing taste when written with heavy writing were judged good, and those that were far from the writing taste were judged bad. The evaluation was performed by three panelists, and ◎ was given when all three felt good, ○ was given when one or two people felt good, and x was given when all three felt bad. . The results are shown in Table 2.

[Test Example 5] (Evaluation of glare)
The display module (tablet terminal) in the touch panel manufactured in the example and the comparative example is displayed in green on the entire surface (RGB values (R, G, B) = 0, 128, 0). Evaluation was performed. The results are shown in Table 2.
(Double-circle): The glare was not confirmed.
○: Slight glare was confirmed, but it was a glare that was not problematic for practical use.
X: Glare was confirmed.

[Test Example 6] (Evaluation of display image visibility)
The display module (tablet terminal) in the touch panel manufactured in the example and the comparative example is displayed in green on the entire surface (RGB values (R, G, B) = 0, 128, 0), and visually displayed images according to the following criteria. Visibility was evaluated. The results are shown in Table 2.
(Double-circle): The visibility fall of the display image was not confirmed.
○: Visibility degradation of the displayed image (white brown, blurred image, etc.) was slightly confirmed (no problem in practical use).
X: Visibility degradation of the displayed image (white brown, blurred image, etc.) was confirmed.

  As is clear from Table 2, the touch panel produced in the example was suppressed in glare, had good visibility of the display image, and was excellent in writing with a touch pen.

  The image display device with a position detection function according to the present invention is suitable as a touch panel excellent in writing quality and visibility.

1A, 1B, 1C, 1D, 1E, 1F, 1G ... Touch panel (image display device with position detection function)
DESCRIPTION OF SYMBOLS 10 ... Writing quality improvement layer 21 ... Base film 22 ... Adhesive layer 22a ... 1st adhesive layer 22b ... 2nd adhesive layer 22c ... 3rd adhesive layer 22d ... 4th adhesive layer 23 ... Cover material 23a ... 1st cover material 23b ... 2nd cover material 23c ... 3rd cover material 24a ... 1st touch sensor 24b ... 2nd touch sensor 30 ... Light-diffusion layer 4, 5 ... Display body module 41a , 51a ... First glass substrate 41b, 51b ... Second glass substrate 41c, 51c ... Third glass substrate 42 ... Module adhesive layer 52a ... First module adhesive layer 52b ... Second module adhesive layer 52c ... third module pressure-sensitive adhesive layer 52d ... fourth module pressure-sensitive adhesive layer 43a, 53a ... first polarizing plate 43b, 53b ... second polarizing plate 44,54 ... color filter 45,5 5 ... Liquid crystal layer 56a ... First touch sensor 56b ... Second touch sensor 47, 57 ... Backlight

Claims (7)

At least a writing quality improving layer that the touch pen contacts, a display module having a color filter, and a light diffusion layer provided at an arbitrary position between the writing quality improving layer and the display module,
Total haze from the writing quality improving layer to the light diffusion layer is 12% or more and 45% or less,
An image display device with a position detection function, wherein a distance between the light diffusion layer and the color filter is 4 mm or less. The image display device with a position detection function includes a base film,
The image display device with a position detection function according to claim 1, wherein the writing quality improving layer is provided on one surface side of the base film.   A pen tip of a hard felt core touch pen having a pen tip diameter of 0.5 mm is brought into contact with a surface in contact with the surface of the touch improvement layer of the writing quality improving layer in a vertical direction under a pressure of 3.92 N, and the writing quality improving layer is The pen tip resistance is measured while moving in one arbitrary direction parallel to the surface of the tip at a speed of 100 mm / min, and the obtained moving distance-pen tip resistance force chart is Fourier transformed, and the frequency obtained by the conversion The average value of the amplitude in the frequency range of 1 to 2 Hz acquired from the amplitude chart is 1.0 or more and 10 or less, and the peak number of the amplitude is 4 or more and 30 or less. The image display device with a position detection function according to claim 1 or 2.   4. The position detection function according to claim 1, wherein the writing quality improving layer is a layer formed by curing a coating composition containing a curable component and fine particles. Image display device.   The said light-diffusion layer is a layer formed from the adhesive composition containing an adhesion component and light-diffusion microparticles | fine-particles, The position detection function as described in any one of Claims 1-4 characterized by the above-mentioned. Image display device.   The image display device with a position detection function according to claim 1, wherein the light diffusion layer is provided adjacent to the display module.   The image display device with a position detection function according to claim 2, wherein the light diffusion layer is provided so as to be adjacent to the base film on which the writing quality improving layer is provided.

Images