CN108459365B - Image display device with position detection function - Google Patents

Image display device with position detection function Download PDF

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Publication number
CN108459365B
CN108459365B CN201711335916.2A CN201711335916A CN108459365B CN 108459365 B CN108459365 B CN 108459365B CN 201711335916 A CN201711335916 A CN 201711335916A CN 108459365 B CN108459365 B CN 108459365B
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Prior art keywords
layer
light diffusion
writing feeling
diffusion layer
adhesive layer
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CN108459365A (en
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星野弘气
仓本达己
户高昌也
大类知生
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Lintec Corp
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Lintec Corp
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    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/02—Diffusing elements; Afocal elements
    • G02B5/0205—Diffusing elements; Afocal elements characterised by the diffusing properties
    • G02B5/0236—Diffusing elements; Afocal elements characterised by the diffusing properties the diffusion taking place within the volume of the element
    • G02B5/0242—Diffusing elements; Afocal elements characterised by the diffusing properties the diffusion taking place within the volume of the element by means of dispersed particles
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
    • G02B1/10—Optical coatings produced by application to, or surface treatment of, optical elements
    • G02B1/11—Anti-reflection coatings
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/033—Pointing devices displaced or positioned by the user, e.g. mice, trackballs, pens or joysticks; Accessories therefor
    • G06F3/0354—Pointing devices displaced or positioned by the user, e.g. mice, trackballs, pens or joysticks; Accessories therefor with detection of 2D relative movements between the device, or an operating part thereof, and a plane or surface, e.g. 2D mice, trackballs, pens or pucks
    • G06F3/03545—Pens or stylus

Abstract

The technical problem is as follows: the invention provides an image display device with a position detection function, which can not damage the writing feeling of a touch pen, can inhibit glare and has good visibility of a displayed image. The solution is as follows: a video display device (1A) having a position detection function, comprising at least: the touch-sensitive display device comprises a writing feeling improving layer (10) which is contacted by a stylus, a display module (4) having a color filter (44), and a light diffusion layer (30) arranged at any position between the writing feeling improving layer (10) and the display module (4), wherein the total haze from the writing feeling improving layer (10) to the light diffusion layer (30) is 12% to 45%, and the distance between the light diffusion layer (30) and the color filter (44) is 4mm or less.

Description

Image display device with position detection function
Technical Field
The present invention relates to an image display device having a position detection function using a stylus.
Background
In recent years, an image display device (touch panel) having a position detection function, which serves as both a display device and an input unit, has been widely used in various electronic devices. In such a touch panel, input can be performed by a stylus pen in addition to input by a finger, and when a stylus pen is used, input operation finer and more accurate than that of a finger can be performed. However, the display module of the touch panel is generally rigid. Therefore, the feeling of writing with a stylus is not good as compared with the feeling of writing with a pencil, a pen, or the like on paper.
In order to solve the problem of the writing feeling of using a stylus pen on a touch panel, it has been studied to attach a film for improving the writing feeling (hereinafter, also referred to as "writing feeling improving film") to the outermost surface of the touch panel. As such a film, for example, patent document 1 discloses a touch film including: the touch-sensitive film comprises a transparent base film and linear protrusions having a mesh structure formed on at least one surface of the transparent base film, wherein the mesh structure has a plurality of regularly arranged blocks, and the linear protrusions occupy 5 to 80% of the entire surface of the touch-sensitive film.
Documents of the prior art
Patent document
Patent document 1: japanese patent laid-open publication No. 2015-054417
Disclosure of Invention
Technical problem to be solved
However, in the conventional writing feeling improving film, a phenomenon of so-called "glare" occurs in which image light of the touch panel is scattered and a part of the image light flickers and dazzles.
The present invention has been made in view of the above circumstances, and an object thereof is to provide an image display device having a position detection function, which can suppress glare without impairing the writing feeling of a stylus pen and has excellent visibility of a displayed image.
(II) technical scheme
In order to achieve the above object, a first aspect of the present invention provides an image display device having a position detection function, comprising at least: the touch-sensitive display device comprises a writing sensation improvement layer contacted by a stylus, a display module having a color filter film, and a light diffusion layer provided at an arbitrary position between the writing sensation improvement layer and the display module, wherein the Total Haze (Total Haze) from the writing sensation improvement layer to the light diffusion layer is 12% or more and 45% or less, and the distance between the light diffusion layer and the color filter film is 4mm or less (invention 1). Here, the "writing feeling improving layer" in the present specification means a layer which improves the writing feeling with a stylus pen as compared with a case where the writing feeling improving layer is not provided, for example, a layer which improves the writing feeling as compared with a case where the stylus pen is directly used on a base film.
In the invention (invention 1), by setting the total haze and the distance between the light diffusion layer and the color filter as described above, glare can be suppressed and visibility of a displayed image can be improved. Further, the above-mentioned physical properties and constitution do not impair the writing feeling of the touch pen provided by the writing feeling improving layer.
In the above invention (invention 1), it is preferable that the image display device with a position detection function includes a base film, and the writing feeling improving layer is provided on one surface side of the base film (invention 2).
In the above inventions (inventions 1 and 2), it is preferable that a tip of a stylus pen having a hard felt tip with a tip diameter of 0.5mm is brought into contact with a surface of the writing feeling enhancement layer, which is in contact with the stylus pen, in a vertical direction under a pressure condition of a load of 3.92N, and moved in any one direction parallel to the surface of the writing feeling enhancement layer at a speed of 100 mm/min to measure a tip resistance, that an average value of amplitudes in a frequency range of 1 to 2Hz obtained from a frequency-amplitude graph obtained by fourier transform of the graph of the obtained movement distance-tip resistance is 1.0 or more and 10 or less, and that the number of peaks of the amplitudes is 4 or more and 30 or less. (invention 3).
In the above inventions (inventions 1 to 3), it is preferable that the writing feeling-improving layer is a layer obtained by curing a coating composition containing a curable component and fine particles (invention 4).
In the above inventions (inventions 1 to 4), it is preferable that the light diffusion layer is a layer formed of an adhesive composition containing an adhesive component and light diffusion fine particles (invention 5).
In the above inventions (inventions 1 to 5), it is preferable that the light diffusion layer is provided adjacent to the display module (invention 6).
In the above invention (invention 2), it is preferable that the light diffusion layer is provided adjacent to the base film on which the writing feeling enhancement layer is provided (invention 7).
(III) advantageous effects
The image display device with position detection function of the invention can not damage the writing feeling of the touch pen, restrain glare and has good visibility of the displayed image.
Drawings
Fig. 1 is a sectional view of an image display device having a position detection function according to a first embodiment of the present invention.
Fig. 2 is a cross-sectional view of an image display device having a position detection function according to a second embodiment of the present invention.
Fig. 3 is a cross-sectional view of an image display device having a position detection function according to a third embodiment of the present invention.
Fig. 4 is a cross-sectional view of an image display device having a position detection function according to a fourth embodiment of the present invention.
Fig. 5 is a sectional view of an image display device having a position detection function according to a fifth embodiment of the present invention.
Fig. 6 is a cross-sectional view of an image display device having a position detection function used in a comparative example.
Fig. 7 is a cross-sectional view of an image display device having a position detection function used in a comparative example.
Detailed Description
Hereinafter, embodiments of the present invention will be described.
An image display device having a position detection function (hereinafter, also referred to as a "touch panel") according to an embodiment of the present invention includes at least: a writing feeling improving layer contacted by the stylus; a display module with a color filter film; and a light diffusion layer disposed at an arbitrary position between the writing feeling improving layer and the display module. Specific examples are shown and described below.
[ first embodiment ]
As shown in fig. 1, a touch panel 1A according to a first embodiment of the present invention is composed of: a writing feeling improving layer 10 contacted by the stylus pen; a base material film 21 which is located on the stylus non-contact side (lower side in fig. 1) of the writing sensation enhancement layer 10 and on which the writing sensation enhancement layer 10 is formed; a first adhesive layer 22a for bonding to the base film 21; a covering material 23 bonded to the base film 21 with a first adhesive layer 22a interposed therebetween; a second adhesive layer 22b for attaching the cover material 23; a first touch sensor 24a bonded to the cover material 23 with the second adhesive layer 22b interposed therebetween; a third adhesive layer 22c for attaching the first touch sensor 24 a; a second touch sensor 24b attached to the first touch sensor 24a with a third adhesive layer 22c interposed therebetween; a light diffusion layer 30 having adhesiveness for attaching the second touch sensor 24 b; and a display module 4 bonded to the second touch sensor 24b with the light diffusion layer 30 interposed therebetween.
The display body module 4 is not particularly limited as long as it is a display body module having a color filter, and a Liquid Crystal (LCD) module, a Light Emitting Diode (LED) module, an organic electroluminescence (organic EL) module, or the like is generally used. In fig. 1, a liquid crystal module is illustrated as an example. In the present embodiment, the display body module 4 is constituted by: a first glass substrate 41a adjacent to the light diffusion layer 30; a module adhesive layer 42 located on the lower side of the first glass substrate 41 a; a first polarizing plate 43a located below the module adhesive layer 42; a second glass substrate 41b positioned below the first polarizing plate 43 a; a color filter 44 on the lower side of the second glass substrate 41 b; a liquid crystal layer 45 positioned below the color filter 44; a third glass substrate 41c positioned below the liquid crystal layer 45; a second polarizing plate 43b located below the third glass substrate 41 c; and a backlight 47 positioned at a lower side of the second polarizing plate 43 b.
1. Physical Properties
In the touch panel 1A of the present embodiment, the total haze from the writing feeling enhancement layer 10 to the light diffusion layer 30 is 12% or more and 45% or less. The total haze is 12% or more, and thus glare of the touch panel can be suppressed. When the total haze is 45% or less, discoloration, blurring, and the like of a displayed image can be suppressed, and good visibility of the displayed image can be maintained. The total haze of the touch panel 1A of the present embodiment from the writing sensation improvement layer 10 to the light diffusion layer 30 is the haze (total of the internal haze and the external haze) of the entire laminate of the writing sensation improvement layer 10, the base film 21, the first adhesive layer 22a, the cover material 23, the second adhesive layer 22b, the first touch sensor 24a, the third adhesive layer 22c, the second touch sensor 24b, and the light diffusion layer 30. The haze in the present specification is defined as JIS K7136: 2000 is a value measured on the basis.
From the viewpoint of glare suppression, the total haze is preferably 14%, particularly preferably 16% or more, and further preferably 18% or more. From the viewpoint of visibility of a displayed 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 of the present embodiment, the distance between the light diffusion layer 30 and the color filter 44 is 4mm or less. The distance between the light diffusion layer 30 and the color filter 44 is 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. If the distance exceeds 4mm, the displayed image may be discolored or blurred, and the visibility of the displayed image may be reduced. That is, the distance is 4mm or less, whereby the visibility of the display image can be maintained well.
From the viewpoint of visibility of a displayed image, the distance is preferably 3mm or less. On the other hand, the lower limit of the distance is not particularly limited, but is usually 0.005mm or more, preferably 0.01mm or more.
Further, 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 feeling of the stylus provided by the writing feeling improving layer 10.
Further, in the touch panel 1A of the present embodiment, the tip of the stylus pen having a hard felt pen tip with a tip diameter of 0.5mm is brought into contact with the surface of the writing feeling enhancement layer, which is in contact with the stylus pen, in the vertical direction under a pressure condition of a load of 3.92N, and moving the writing tip in any direction parallel to the surface of the writing feeling enhancement layer 10 at a speed of 100 mm/min to measure the pen tip resistance (mN), the obtained graph of the moving distance (mm) and the pen tip resistance (mN) is fourier-transformed, and the average value of the amplitude in the range of the frequency of 1 to 2Hz, which is obtained from the frequency (Hz) -amplitude graph (one) obtained by the transformation, is preferably 1.0 or more and 10 or less, and the peak value number (amplitude number) of the amplitude is preferably 4 or more and 30 or less (from this physical property of the pen smoothness test, hereinafter, also referred to as "writing feeling physical property"). Further, the fourier transform was performed using software (manufactured by Microsoft corporation, software name "Excel"). By setting the average value of the amplitude and the number of amplitudes within the above ranges, a preferable resistance feeling and friction feeling are given to the writing feeling using the stylus pen. In combination with these feelings, the writing feeling of the stylus becomes similar to that when writing on paper using a pencil, and thus becomes an excellent feeling.
The reason why the amplitude in the frequency range of 1 to 2Hz is defined is that the inventors have found empirically that: when the vibration during writing is regarded as the superposition of a plurality of vibrations having various frequencies, the characteristic vibration recognized as "writing feeling" by a human being in particular is a vibration having a frequency in the range of 1 to 2 Hz.
Further, as the stylus, for example, in addition to a stylus having a hard felt tip with a tip diameter of 0.1 to 5mm, a stylus having a polyacetal (polyacetal) tip may be used, and the above-described effects can be obtained by using any stylus.
Here, the "pen tip resistance" refers to a resistance applied to the pen tip when the stylus is moved under the above-described conditions. The "peak number" refers to a peak number having an amplitude of 1.5 or more in a frequency range of 1 to 2 Hz.
The average value of the amplitude is particularly preferably 1.5 or more from the viewpoint of the writing feeling using a stylus pen. The average value of the amplitudes is particularly preferably 4 or less. The number of amplitudes is preferably 5 or more, particularly preferably 6 or more, and further preferably 8 or more. The number of amplitudes is particularly preferably 20 or less, and more preferably 15 or less.
From the viewpoint of further improving the writing feeling with the stylus pen, the maximum value of the amplitude (maximum amplitude value) is preferably 1.3 or more, particularly preferably 2.0 or more, and further preferably 2.4 or more. The maximum value of the amplitude is preferably 10 or less, particularly preferably 8 or less, and further preferably 5 or less.
A specific method for obtaining the graph of the travel distance (mm) and the pen point resistance (mN) is shown in test examples described later.
2. Parts of
(1) Layer for improving writing feeling
The writing feeling improving layer 10 in the present embodiment is a layer that improves the writing feeling of a stylus pen compared to when the stylus pen is used directly on the base film 21. Preferably, the writing feeling improving layer 10 is a coating layer formed by a coating composition on one surface side of the base film 21, but is not limited thereto.
(1-1) Material for writing feeling-improving layer
The writing feeling improving layer 10 of the touch panel 1A of the present embodiment can improve the writing feeling of the stylus pen compared to when the stylus pen is used as it is on the base film 21, and may be formed of any material as long as it is formed of a material having good optical characteristics. In the present embodiment, the writing feeling enhancement layer 10 is formed by curing the coating composition C described below. When the coating composition C is used, the writing feeling improving layer 10 satisfying the above-described physical properties of writing feeling can be easily formed.
The coating composition C of the present embodiment preferably contains a curable component and fine particles.
(1-1-1) curable component
The curable component is a component that is cured by activation (trigger) of an active energy ray, heat, or the like, and examples thereof include an active energy ray-curable component, a thermosetting component, and the like. In the present embodiment, it is preferable to use an active energy ray-curable component from the viewpoint of improving the hardness of the formed writing feeling enhancement layer 10, the heat resistance of the base film 21, and the like.
The active energy ray-curable component is preferably a component which is cured by irradiation with an active energy ray, and can exhibit a predetermined hardness and realize the above-described writing feeling physical properties in relation to fine particles.
Specific examples of the active energy ray-curable component include polyfunctional (meth) acrylate monomers, (meth) acrylate prepolymers, and active energy ray-curable polymers, and among them, polyfunctional (meth) acrylate monomers and/or (meth) acrylate prepolymers are preferable, and polyfunctional (meth) acrylate monomers are more preferable. The polyfunctional (meth) acrylate monomer and the (meth) acrylate prepolymer may be used alone or in combination. In the present specification, the term (meth) acrylate refers to both acrylate and methacrylate. Other similar terms are also the same.
Examples of the polyfunctional (meth) acrylate monomer include 1, 4-butanediol di (meth) acrylate, 1, 6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate hydroxytrimethylacetate, dicyclopentanyl di (meth) acrylate, caprolactone-modified dicyclopentenyl di (meth) acrylate, ethylene oxide-modified di (meth) acrylate phosphate, allylated cyclohexyl di (meth) acrylate, isocyanurate di (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, propionic acid-modified dipentaerythritol tri (meth) acrylate, pentaerythritol di (meth) acrylate, and mixtures thereof, Polyfunctional (meth) acrylates such as propylene oxide-modified trimethylolpropane tri (meth) acrylate, tris (acryloyloxyethyl) isocyanurate, propionic acid-modified dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ethylene oxide-modified dipentaerythritol hexa (meth) acrylate, and caprolactone-modified dipentaerythritol hexa (meth) acrylate. These may be used alone or in combination of two or more.
On the other hand, as the (meth) acrylate-based prepolymer, for example, prepolymers of polyester acrylates, epoxy acrylates, urethane acrylates, polyol acrylates, and the like are cited.
The polyester acrylate prepolymer may be obtained by, for example, esterifying the hydroxyl group of a polyester oligomer having hydroxyl groups at both ends obtained by condensation of a polyvalent carboxylic acid and a polyvalent alcohol with (meth) acrylic acid, or esterifying the hydroxyl group at the end of an oligomer obtained by addition of an alkylene oxide (alkylene oxide) to a polyvalent carboxylic acid with (meth) acrylic acid.
The epoxy acrylate prepolymer can be obtained by, for example, esterifying (meth) acrylic acid by reacting with an oxirane ring (oxirane ring) of a relatively low molecular weight bisphenol epoxy resin, a phenol epoxy resin, or the like.
The urethane acrylate prepolymer is obtained, for example, by esterifying a urethane oligomer obtained by reacting a polyether polyol, a polyester polyol, or the like with a polyisocyanate (polyisocynate) with (meth) acrylic acid.
The polyol acrylate prepolymer can be obtained, for example, by esterifying the hydroxyl groups of a polyether polyol with (meth) acrylic acid.
The above-mentioned prepolymers may be used singly or in combination of two or more.
In addition, as the active energy ray-curable component, an organic-inorganic hybrid (hybrid) resin is preferably used. The organic-inorganic hybrid resin is preferably one in which, for example, silica fine particles are bonded to an organic compound having a polymerizable unsaturated group through a silane coupling agent or the like. The silica fine particles contained in the organic-inorganic hybrid resin function as a binder as a silica sol (silica sol), and are not included in the fine particles described below.
When an organic-inorganic hybrid resin is used, the above-mentioned writing feeling physical properties can be easily obtained by the action of the silica sol. Therefore, by using spherical organic fine particles as the fine particles described later, the writing feeling physical properties can be easily obtained, and thus the optical properties of the formed writing feeling-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 high surface hardness to the writing feeling enhancement layer 10, and organic fine particles are preferable from the viewpoint of further enhancing the optical properties of the writing feeling enhancement layer 10. The fine particles may be spherical or non-spherical. In the case of non-spherical shapes, the shapes may be indefinite, or shapes having a high aspect ratio such as needles or scales. The term "amorphous" as used herein means a shape having a plurality of irregular corners or faces, rather than a regular shape such as a spherical shape or an elliptical shape. In addition, the fine particles may be used singly or in combination of two or more.
Examples of the inorganic fine particles include metal oxides such as silica, alumina, zirconia, titania, zinc oxide, germanium oxide, indium oxide, tin oxide, Indium Tin Oxide (ITO), antimony oxide, and cerium oxide; and fine particles of metal fluorides such as magnesium fluoride and sodium fluoride. Among these, silica and alumina are preferable, silica is particularly preferable, and amorphous silica is more preferable, from the viewpoint of imparting high surface hardness and little influence on optical characteristics. The surface of the inorganic fine particles may be chemically modified with an organic compound or the like.
Examples of the organic fine particles include silicone fine particles, melamine resin fine particles, acrylic resin fine particles (e.g., polymethyl methacrylate resin fine particles), acrylic-styrene copolymer fine particles, polycarbonate resin fine particles, polyethylene resin fine particles, polystyrene fine particles, benzoguanamine (benzoguanamine) resin fine particles, and the like. These resins may also be crosslinked. Among these, acrylic resin fine particles are preferable, polymethyl methacrylate resin fine particles are particularly preferable, spherical polymethyl methacrylate resin fine particles are further preferable, and cross-linked polymethyl methacrylate resin fine particles in a regular spherical shape are most preferable from the viewpoint of optical characteristics and hardness.
In the present embodiment, in order to obtain the above writing feeling physical properties, it is preferable to use amorphous 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 diameter 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 mean particle diameter 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 diameter of the amorphous fine particles is in the above range, the above writing feeling physical properties can be easily obtained. In the present specification, the average particle diameter of the fine particles is a value measured by a laser diffraction scattering particle size distribution measuring apparatus.
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 writing feeling physical properties can be easily obtained.
The particle size distribution of the fine particles is preferably 20% or more, more preferably 40% or more, and even more preferably 70% or more, from the viewpoint of the writing feeling physical properties of the writing feeling improving layer 10, using a coefficient of variation (CV value) of the particle size expressed by the following formula. 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 diameter (CV value) (%) (standard deviation particle diameter/average particle diameter) × 100
The coefficient of variation (CV value) of the particle diameter is a value measured by a laser diffraction scattering particle size distribution measuring apparatus (product name "LA-920" manufactured by horiba Ltd.).
The content of the amorphous fine particles in the coating composition C is preferably 3% by mass or more, more preferably 4% by mass or more, particularly preferably 5% by mass or more, and further preferably 7% by mass or more. The content of the amorphous fine particles is preferably 40% by mass or less, more preferably 35% by mass or less, particularly preferably 30% by mass or less, and further preferably 20% by mass or less. When the content of the amorphous fine particles is in the above range, the writing feeling physical properties can be easily obtained.
The content of spherical fine particles in the coating composition C is preferably 3% by mass or more, particularly preferably 4% by mass or more, and more 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 writing feeling physical properties can be easily obtained.
(1-1-3) photopolymerization initiator
When ultraviolet rays are used as the active energy rays for curing the active energy ray-curable component, the coating composition C preferably contains a photopolymerization initiator. By containing the photopolymerization initiator, the active energy ray-curable component can be efficiently polymerized, and the polymerization curing time and the irradiation amount of ultraviolet rays can be reduced.
Examples of such photopolymerization initiators include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylaminoacetophenone, 2-dimethoxy-2-phenylacetophenone, 2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1- [4- (methylthio) phenyl ] -2-morpholinyl-propan-1-one, 4- (2-hydroxyethoxy) phenyl-2- (hydroxy-2-propyl) ketone, diphenylketone, p-phenyldiphenylketone, and, 4,4' -diethylamino-diphenyl ketone, dichlorodiphenyl ketone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone, 2-aminoanthraquinone, 2-methylthioxanthone (2-methylthioxanthone), 2-ethylthioxanthone (2-ethioxoanthone), 2-chlorothioxanthone (2-chlorothioxanthone), 2,4-dimethylthioxanthone (2,4-dimethylthioxanthone), 2,4-diethylthioxanthone (2,4-diethylthioxanthone), benzyl dimethyl ketal (benzyl dimethyl ketal), acetophenone dimethyl ketal (acetophenone dimethyl ketal), p-dimethylaminobenzoate (p-dimethylaminobenzoic acid), 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 part by mass or more, particularly preferably 0.1 part by mass or more, and further preferably 1 part by mass or more, per 100 parts by mass of the active energy ray-curable component. 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
In addition to the above-mentioned components, the coating composition C may also contain various additives. Examples of the various additives include leveling agents (leveling agents), ultraviolet absorbers, antioxidants, light stabilizers, antistatic agents, silane coupling agents, aging inhibitors, thermal polymerization inhibitors, colorants, surfactants, storage stabilizers, plasticizers, lubricants, defoaming agents, wettability improvers, finish improvers, and the like.
(1-2) thickness of writing feeling-improving layer
The lower limit of the thickness of the writing feeling enhancement layer 10 is preferably 0.5 μm or more, more preferably 0.7 μm or more, particularly preferably 1.0 μm or more, and further preferably 1.3 μm or more. When the lower limit of the thickness of the writing feeling enhancement layer 10 is the above value, the above writing feeling physical properties can be easily satisfied, and good scratch resistance can be obtained. The upper limit of the thickness of the writing feeling enhancement layer 10 is preferably 20 μm or less, more preferably 15 μm or less, and still more preferably 10 μm or less. When the upper limit value of the thickness of the writing feeling enhancement layer 10 is the above value, the mixing of the residual solvent, air bubbles, and the like caused in the production process can be effectively prevented, a good writing feeling enhancement layer 10 can be easily obtained, and the above writing feeling physical properties can be satisfied.
(2) Substrate film
The base film 21 may be selected as appropriate from among films suitable for a touch panel using a stylus pen, and is preferably a plastic film having good affinity with the writing feeling improving layer 10.
Examples of the plastic film include polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyolefin films such as polyethylene films and polypropylene films; a plastic film such as cellophane, a cellulose diacetate film, a cellulose triacetate film, a cellulose acetate butyrate film, a polyvinyl chloride film, a polyvinylidene chloride film, a polyvinyl alcohol film, an ethylene-vinyl acetate copolymer film, a polystyrene film, a polycarbonate film, a polymethylpentene film, a polysulfone film, a polydietherketone film, a polyethersulfone film, a polyetherimide film, a fluororesin film, a polyamide film, an acrylic resin film, a polyurethane resin film, a norbornene polymer film, a cyclic olefin polymer film, a cyclic conjugated diene polymer film, an ethylene alicyclic hydrocarbon polymer film, or a laminate film thereof. Among these, a polyethylene terephthalate film, a polycarbonate film, a norbornene polymer film, and the like, which can maintain the writing feeling of the stylus pen well when combined with the writing feeling enhancement layer 10, are preferable, and a polyethylene terephthalate film is particularly preferable.
In the base film 21, for the purpose of improving adhesion to a layer (the writing feeling improving layer 10, an adhesive agent layer described later, or the like) provided on the surface thereof, surface treatment may be performed on one side or both sides by primer (primer) treatment, oxidation, embossing, or the like, as necessary. Examples of the oxidation method include corona discharge treatment, chromic acid treatment, flame treatment, hot air treatment, and ozone-ultraviolet treatment, and examples of the concavo-convex method include sand blast method and solvent treatment method. These surface treatment methods can be appropriately selected depending on the kind of the base material film 21. For example, a plastic film having an easy-adhesion layer formed by primer treatment is preferably used, and a polyethylene terephthalate film is particularly preferably used.
The thickness of the base film 21 is preferably 15 to 300. mu.m, particularly preferably 30 to 200. mu.m, and further preferably 90 to 150. mu.m.
(3) Adhesive layer
The first adhesive layer 22a, the second adhesive layer 22b, and the third adhesive layer 22c may be formed according to the adhesive or the adhesive sheet required respectively. As the adhesive constituting these adhesive layers, adhesives commonly used for optical applications can be used, and examples thereof include acrylic adhesives, rubber adhesives, silicone adhesives, urethane adhesives, polyester adhesives, and polyvinyl ether adhesives. Among them, acrylic adhesives exhibiting desired tackiness and excellent optical characteristics and durability are preferable.
The thicknesses of the first adhesive layer 22a, the second adhesive layer 22b, and the third adhesive layer 22c are preferably 5 to 1000 μm, particularly preferably 7 to 500 μm, and more preferably 10 to 250 μm, respectively.
(4) Covering material
The cover material 23 protects the touch sensors 24a and 24b of the touch panel 1A and the display body module 4, and is generally configured with a glass plate or a plastic plate as a main body. The glass plate is not particularly limited, and examples thereof include chemically strengthened glass, alkali-free glass, quartz glass, soda-lime glass, barium-strontium-containing glass, aluminosilicate glass, lead glass, borosilicate glass, and barium borosilicate glass. The plastic plate is not particularly limited, and examples thereof include acrylic plates and polycarbonate plates made of polymethyl methacrylate.
Further, functional layers such as a hard coat layer, an antireflection layer, and an antiglare layer may be provided on one or both surfaces of the glass plate, the plastic plate, and the like, and optical members such as a hard coat film, an antireflection film, and an antiglare film may be laminated.
In the present embodiment, the covering material 23 may have a level difference (not shown) due to a printed layer or the like on the surface on the second adhesive layer 22b side. The printed layer is generally formed in a frame shape in plan view.
The thickness of the covering material 23 is preferably 10 to 3000 μm, particularly preferably 25 to 2000 μm, and further preferably 50 to 1500 μm.
(5) Touch sensor
In the touch panel 1A, the first touch sensor 24a and the second touch sensor 24b have a function of detecting the position of a touch point.
The touch sensors 24a and 24b are preferably formed of a transparent film and a patterned transparent conductive film, but not limited thereto. The positional relationship between the transparent film and the transparent conductive film is not particularly limited.
The transparent film is not particularly limited, and for example, a polyethylene terephthalate film, a polyethylene naphthalate film, a polycarbonate film, a polymethyl methacrylate film, a cellulose triacetate film, a polypropylene film, or the like can be 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 oxide; composite oxides such as tin-doped indium oxide (ITO), zinc-doped indium oxide, fluorine-doped indium oxide, antimony-doped tin oxide, fluorine-doped tin oxide, and aluminum-doped zinc oxide; chalcogenides (chalcogenides), lanthanum hexaboride, titanium nitride, titanium carbide, and other non-oxide compounds, and among them, tin-doped indium oxide (ITO) is preferred.
The thickness of each of the touch sensors 24a and 24b is preferably 10 to 300 μm, particularly preferably 15 to 250 μm, and further preferably 20 to 200 μm.
(6) Light diffusion layer
The light diffusion layer 30 in the present embodiment preferably has adhesiveness for bonding to the second touch sensor 24b and the display module 4, and is preferably made of an adhesive having light diffusion properties. Such a light diffusion layer having adhesiveness may also be referred to as an "adhesive light diffusion layer".
(6-1) Material for light diffusion layer
The light diffusion layer 30 is preferably formed of an adhesive composition containing an adhesive component and light diffusion fine particles (hereinafter referred to as "adhesive composition P").
The adhesive component is not particularly limited as long as it can exhibit the required adhesiveness for a touch panel or the like, has light permeability, and does not inhibit the effect of the light diffusion particles. Examples of such adhesive components include acrylic adhesive components, rubber adhesive components, silicone adhesive components, polyurethane adhesive components, and polyester adhesive components, among which acrylic adhesive components are preferred from the above viewpoint.
The acrylic pressure-sensitive adhesive component preferably contains a (meth) acrylate polymer (a), and particularly preferably contains a (meth) acrylate polymer (a) crosslinked by a crosslinking agent (B). In the present specification, the term "polymer" also includes the term "copolymer".
(6-1-1) (meth) acrylate ester Polymer (A)
The (meth) acrylate polymer (A) preferably contains an alkyl (meth) acrylate having 1 to 20 alkyl carbon atoms as a monomer constituting the polymer. Thus, the resulting light diffusion layer 30 can exhibit better adhesiveness. The (meth) acrylate polymer (a) is preferably a copolymer of an alkyl (meth) acrylate having 1 to 20 alkyl carbon atoms, a monomer having a functional group that reacts with the crosslinking agent (B) (a reactive functional group-containing monomer), and other monomers that can be used as needed.
Examples of the alkyl (meth) acrylate having 1 to 20 carbon atoms in the alkyl group include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, n-decyl (meth) acrylate, n-dodecyl (meth) acrylate, myristyl (meth) acrylate, palmityl (meth) acrylate, and stearyl (meth) acrylate. Among them, from the viewpoint of further improving the adhesion, preferred are (meth) acrylates having 1 to 8 alkyl carbon atoms, and more preferred are methyl (meth) acrylate, n-butyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate. These may be used alone or in combination of two or more.
The (meth) acrylate polymer (A) preferably contains 30 to 95 mass% of an alkyl (meth) acrylate having 1 to 20 alkyl carbon atoms, particularly preferably 40 to 90 mass%, and further preferably 50 to 85 mass% of a monomer unit constituting the polymer.
Examples of the reactive functional group-containing monomer include 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), and a monomer having an amino group in the molecule (amino group-containing monomer).
Examples of the hydroxyl group-containing monomer include hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate. Among them, 2-hydroxyethyl (meth) acrylate is preferable from the viewpoint of reactivity of the hydroxyl group in the obtained (meth) acrylate polymer (a) with the crosslinking agent (B) and copolymerizability with other monomers. 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) acrylate polymer (a) contains a reactive functional group-containing monomer as a monomer constituting the polymer, the content thereof is preferably 5 to 35% by mass, particularly preferably 10 to 30% by mass, and further preferably 20 to 25% by mass.
The (meth) acrylate polymer (a) may contain, as a monomer unit constituting the polymer, another monomer, if necessary. As the other monomer, a monomer containing no functional group having reactivity is preferable. Examples of such other monomers include alkoxyalkyl (meth) acrylates such as methoxyethyl (meth) acrylate and ethoxyethyl (meth) acrylate; and (meth) acrylic esters having an alicyclic ring such as cyclohexyl (meth) acrylate, (meth) acrylic esters having a non-crosslinkable tertiary amino group such as N, N-dimethylaminoethyl (meth) acrylate and N, N-dimethylaminopropyl (meth) acrylate, vinyl acetate, styrene, and the like. These may be used alone or in combination of two or more.
The polymerization form of the (meth) acrylate polymer (a) may be a random copolymer or a block copolymer.
The weight average molecular weight of the (meth) acrylate polymer (a) is preferably 10 to 200 ten thousand, particularly preferably 20 to 130 ten thousand, and further preferably 30 to 80 ten thousand. The weight average molecular weight in the present specification is a standard polystyrene conversion value measured by a Gel Permeation Chromatography (GPC) method.
In the adhesive composition P, the (meth) acrylate polymer (a) may be used alone or in combination of two or more.
(6-1-2) crosslinking agent (B)
The adhesive composition P contains the adhesive components: in the case of the (meth) acrylate polymer (a) containing a reactive functional group-containing monomer as a monomer unit constituting the polymer and the 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) acrylate polymer (a). In this way, the crosslinking agent (B) forms a structure in which the (meth) acrylate polymer (a) is crosslinked, thereby improving the strength, durability, and the like of the light diffusion layer 30.
The crosslinking agent (B) may be any agent that can react with the reactive functional group of the (meth) acrylate polymer (a), and examples thereof include isocyanate (isocyanate) crosslinking agents, epoxy resin crosslinking agents, amine crosslinking agents, melamine crosslinking agents, aziridine (azidine) crosslinking agents, hydrazine (hydrazine) crosslinking agents, aldehyde crosslinking agents, oxazoline (oxazoline) crosslinking agents, metal alkoxide crosslinking agents, metal chelate crosslinking agents, metal salt crosslinking agents, and ammonium salt crosslinking agents. Among these, when the reactive functional group of the (meth) acrylate polymer (a) is a hydroxyl group, an isocyanate-based crosslinking agent having excellent reactivity with a hydroxyl group is preferably used, and when the reactive functional group of the (meth) acrylate polymer (a) is a carboxyl group, an epoxy resin-based crosslinking agent having excellent reactivity with a carboxyl group is preferably used. Further, the crosslinking agent (B) may be used alone or in combination of two or more.
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 cyclohexane diisocyanate; and alicyclic polyisocyanates such as isophorone diisocyanate and hydrogen-added diphenylmethane diisocyanate, biuret (biuret) products, isocyanurate (isocyanurate) products thereof, and adducts of these with low-molecular-weight active hydrogen-containing compounds such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, and castor oil. Among them, trimethylolpropane-modified aromatic polyisocyanates are preferable from the viewpoint of reactivity with hydroxyl groups, and trimethylolpropane-modified tolylene diisocyanate and trimethylolpropane-modified xylylene diisocyanate are particularly preferable.
Examples of the epoxy resin-based crosslinking agent include 1, 3-bis (N, N '-diglycidylaminomethyl) cyclohexane, N' -tetraglycidyl-m-xylylenediamine, ethylene glycol diglycidyl ether, 1, 6-hexanediol diglycidyl ether, trimethylolpropane diglycidyl ether, diglycidylaniline, and diglycidylamine.
The content of the crosslinking agent (B) in the adhesive composition P is preferably 0.001 to 10 parts by mass, particularly preferably 0.01 to 5 parts by mass, and further preferably 0.02 to 1 part by mass, based on 100 parts by mass of the (meth) acrylate polymer (a).
(6-1-3) light diffusing particles
The light-diffusing fine particles may be any of those having the total haze in the above range, and examples thereof include inorganic fine particles such as silica, calcium carbonate, aluminum hydroxide, magnesium hydroxide, clay, talc, and titanium dioxide; acrylic resins such as polymethyl methacrylate resins; organic light-transmitting fine particles such as polystyrene resin, polymethyl methacrylate-polystyrene copolymer, polyethylene resin, and epoxy resin; and microparticles formed of a silicon-containing compound having an intermediate structure of inorganic and organic such as silicone resin (for example, Tospearl series manufactured by Momentive Performance Materials-Japan). Among them, acrylic resin fine particles, polymethyl methacrylate-polystyrene copolymer fine particles, and fine particles of a silicon-containing compound having an inorganic and organic intermediate structure are preferable because they are excellent in dispersibility of the adhesive component and can obtain uniform optical characteristics. The light diffusing particles may be used alone or in combination of two or more.
The shape of the light diffusing fine particles is preferably a spherical shape in which light is diffused uniformly, and particularly preferably a spherical shape. The average particle diameter of the light diffusing fine particles measured by a laser diffraction method is preferably 0.1 μm or more, particularly preferably 1 μm or more, and more preferably 2 μm or more. The average particle diameter is preferably 20 μm or less, more preferably 10 μm or less, and still more preferably 8 μm or less. When the average particle diameter is within the above range, the total haze value can be easily adjusted to the above range without hindering the light transmittance of the light diffusion layer 30.
The average particle diameter measured by the laser diffraction method was measured by a laser diffraction scattering particle size distribution measuring apparatus using a sample obtained by sufficiently stirring 1.2g of fine particles and 98.8g of isopropyl alcohol 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 preferably 0.01 parts by mass or more, and particularly preferably 0.1 parts by mass or more, based on 100 parts by mass of the (meth) acrylate polymer (a). 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 particles is within the above range, the light transmittance of the light diffusing layer 30 is not hindered, and the total haze value can be easily set within the above range. In addition, the other members adjacent to the light diffusion layer 30 can easily exhibit sufficient adhesiveness, and defects such as accidental peeling can be prevented from occurring. When the adhesive component is other than an acrylic adhesive component, the content of the light diffusing fine particles is preferably in the above range with respect to 100 parts by mass of the adhesive component.
(6-1-4) various additives
The adhesive composition P may also contain various additives such as a silane coupling agent, a refractive index adjuster, an antistatic agent, a tackifier, an antioxidant, an ultraviolet absorber, a light stabilizer, a softener, a filler, and the like, as needed.
(6-2) production of adhesive composition
The adhesive composition P can be produced by mixing an adhesive component, light diffusing fine particles, and additives as needed. When the adhesive component contains the (meth) acrylate polymer (a), the (meth) acrylate polymer (a) is first prepared, and the crosslinking agent (B) is formulated as needed.
The (meth) acrylate polymer (a) can be produced by polymerizing a mixture of monomer units constituting the polymer by a general radical polymerization method. The polymerization of the (meth) acrylate polymer (a) may be carried out by a solution polymerization method or the like using a polymerization initiator as needed. Examples of the polymerization solvent include ethyl acetate, n-butyl acetate, isobutyl acetate, toluene, acetone, hexane, and methyl ethyl ketone, and two or more of them may be used in combination.
Examples of the polymerization initiator include azo compounds and organic peroxides, and two or more kinds thereof may be used in combination. Examples of the azo compound include 2,2' -azobisisobutyronitrile, 2' -azobis (2-methylbutyronitrile), 1' -azobis (cyclohexane 1-carbonitrile), 2' -azobis (2, 4-dimethylvaleronitrile), 2' -azobis (2, 4-dimethyl-4-methoxyvaleronitrile), dimethyl 2,2' -azobis (2-methylpropionic acid), 4' -azobis (4-cyanovaleric acid), 2' -azobis (2-hydroxymethylpropionitrile), and 2,2' -azobis [2- (2-imidazolin-2-yl) propane ].
Examples of the organic peroxide include benzoyl peroxide, t-butyl peroxybenzoate, cumene hydroperoxide, diisopropyl peroxydicarbonate, di-n-propyl peroxydicarbonate, di (2-ethoxyethyl) peroxydicarbonate, t-butyl peroxyneodecanoate (t-butyl peroxyneodecanoate), t-butyl peroxypivalate (t-butyl peroxybivalate), peroxy (3,5, 5-trimethylhexanoyl) peroxide, dipropionyl peroxide, and diacetyl peroxide.
In the above-mentioned polymerization step, a chain transfer agent such as 2-mercaptoethanol (2-mercaptoethanol) can be blended to adjust the weight average molecular weight of the obtained polymer.
After obtaining the (meth) acrylate polymer (a), the light-diffusing fine particles, if necessary, the crosslinking agent (B) and additives are added to the solution of the (meth) acrylate polymer (a), and the mixture is thoroughly mixed to obtain the adhesive composition P (coating liquid) diluted with the solvent.
Examples of the diluting solvent include aliphatic hydrocarbons such as hexane, heptane and cyclohexane; aromatic hydrocarbons such as toluene and xylene; halogenated hydrocarbons such as dichloromethane and dichloroethane; alcohols such as methanol, ethanol, propanol, butanol, and 1-methoxy-2-propanol; ketones such as acetone, butanone, 2-pentanone, isophorone, and cyclohexanone; esters such as ethyl acetate and butyl acetate; and cellosolve solvents such as ethyl cellosolve (ethyl cellosolve).
The concentration and viscosity of the coating liquid prepared in this way are not particularly limited as long as they are within a range in which the coating liquid can be applied, and they may be appropriately selected depending on the case. For example, the adhesive composition P is diluted so that the concentration thereof is 10 to 40 mass%. In addition, when obtaining the coating liquid, the addition of a diluting solvent or the like is not essential, and the diluting solvent may not be added as long as the adhesive composition P has a coatable viscosity or the like.
(6-3) thickness of light diffusion layer
The thickness of the light diffusion layer 30 (value measured in accordance with JIS K7130) is preferably 5 μm or more, particularly preferably 7.5 μm or more, and more preferably 10 μm or more as the lower limit. 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 of the thickness of the light diffusion layer 30 is as described above, the required adhesiveness and optical properties can be achieved at the same time. On the other hand, when the upper limit of the thickness of the light diffusion layer 30 is as described above, the touch panel 1A obtained can be suppressed from being 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 the present embodiment may be a liquid crystal module having the above-described structure, for example. The display module 4 or the members constituting the display module 4, that is, the first glass substrate 41a, the module adhesive layer 42, the first polarizing plate 43a, the second glass substrate 41b, the color filter 44, the liquid crystal layer 45, the third glass substrate 41c, the second polarizing plate 43b, and the backlight 47 may be formed of known members.
As described above, in the touch panel 1A of the present embodiment, the distance between the light diffusion layer 30 and the color filter 44 is 4mm or less. In the case of using the display module 4, the distance is the total thickness of the first glass substrate 41a, the module adhesive layer 42, the first polarizing plate 43a, and the second glass substrate 41 b. The first glass substrate 41a and the second glass substrate 41b each have a thickness of usually 0.1 to 3000 μm, preferably 0.3 to 1500 μm. The thickness of the module adhesive layer 42 is usually 1 to 1000 μm, preferably 5 to 750 μm. The thickness of the first polarizing plate 43a is usually 1 to 1000 μm, preferably 3 to 750 μm. The thicknesses of the light diffusion layer 30 and the color filter 44 are appropriately selected so that the distance therebetween is 4mm or less.
3. Manufacturing method of touch panel
The touch panel 1A of the present embodiment can be manufactured by a common method, but a preferred manufacturing method will be described as an example.
(1) Formation of writing feeling enhancing layer
The writing feeling improving layer 10 is formed on the base film 21. Specifically, the coating composition for the writing feeling enhancement layer 10 is preferably formed by applying a coating liquid containing the coating composition C and, if necessary, a solvent to the base film 21 and curing the coating liquid.
The solvent is not particularly limited as long as it can be used for improving coatability, adjusting viscosity, adjusting solid content concentration, and the like, and can dissolve a curable component or the like, dispersing fine particles, and the like.
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 cellosolve), ethylene glycol monoethyl ether (ethyl cellosolve), diethylene glycol monobutyl ether (butyl cellosolve), and propylene glycol monomethyl ether; aromatic hydrocarbons such as benzene, toluene, and xylene; amides such as dimethylformamide, dimethylacetamide and N-methylpyrrolidone (N-methylpyrrolidinone).
The coating liquid of the coating composition may be applied by a conventional method, and may be applied by, 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. The coating liquid for coating the coating composition is preferably dried at 40 to 120 ℃ for about 30 seconds to 5 minutes.
In the case where the coating composition is active energy ray-curable as in the case of the coating composition C, curing of the coating composition can be performed by irradiating a coating film of the coating composition with active energy rays such as ultraviolet rays or electron beams. The ultraviolet irradiation may be performed by a high pressure mercury lamp, fusion H lamp, xenon lamp, etc., and the ultraviolet irradiation dose is preferably 50-1000 mW/cm2The light amount is 50 to 1000mJ/cm2Degree of the disease. On the other hand, the electron beam irradiation may 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 diffusion layer
The light diffusion layer 30 is preferably formed on a release surface (surface having releasability) of the release sheet to be a light diffusion layer sheet. The light diffusion layer 30 in the present embodiment is preferably formed of the adhesive composition P. Therefore, it is preferable that a coating layer is formed by applying a coating liquid containing the adhesive composition P and a solvent as needed to the release surface of the release sheet and heating the coating liquid. If a curing period is required, the curing period is performed, and if the curing period is not required, the coating layer is left as it is, and the coating layer is made into the light diffusion layer 30, thereby obtaining a light diffusion layer sheet. Further, the drying treatment when the solvent or the like of the adhesive composition P is volatilized may be used as the heating treatment.
When the adhesive composition P contains the (meth) acrylate polymer (a), the heating temperature of the heat treatment is preferably 50 to 150 ℃, and particularly preferably 70 to 120 ℃. The heating time is preferably 30 seconds to 10 minutes, and particularly preferably 50 seconds to 2 minutes. After the heat treatment, if necessary, a curing period of about 1 to 2 weeks may be set at normal temperature (e.g., 23 ℃ C., 50% RH). When the curing period is required, the light diffusion layer 30 is formed after the curing period has elapsed, and when the curing period is not required, the light diffusion layer 30 is formed after the heat treatment is completed.
The method of applying the coating liquid containing the solvent and the adhesive composition P mixed with the adhesive composition P is the same as the method of applying the solvent and the coating liquid of the coating composition for the writing feeling enhancement layer 10.
(3) Formation of adhesive layer
The first adhesive layer 22a, the second adhesive layer 22b, and the third adhesive layer 22c are preferably formed on the release surface of the release sheet to be adhesive sheets. For example, a coating liquid containing an adhesive composition for each adhesive layer and a solvent as needed is applied to the release surface of the release sheet, and dried to form an adhesive layer, thereby obtaining an adhesive sheet.
(4) Lamination of components
The stacking of the components may be performed manually using a press roll or automatically using a laminating apparatus. The order of stacking the members is not particularly limited, and the following method is only an example.
First, in the adhesive sheet of the first adhesive layer 22a, the first adhesive layer 22a is laminated on the surface of the base film 21 on which the writing feeling enhancement layer 10 is formed, the surface being opposite to the writing feeling enhancement layer 10 side. Then, the release sheet is peeled off, and the exposed first adhesive layer 22a is bonded to the covering material 23.
On the other hand, the third adhesive layer 22c is laminated on the first touch sensor 24a in the adhesive sheet of the third adhesive layer 22 c. Then, the release sheet of the adhesive sheet of the third adhesive layer 22c is peeled off, and the exposed third adhesive layer 22c is bonded to the second touch sensor 24 b. Next, the second adhesive layer 22b of the adhesive sheet of the second adhesive layer 22b is bonded to the surface of the first touch sensor 24a on the side opposite to the third adhesive layer 22 c. In the second touch sensor 24b, the light diffusion layer 30 of the light diffusion layer sheet is bonded to the surface on the side opposite to the third adhesive layer 22c side.
Next, the release sheet is peeled off from the adhesive sheet of the second adhesive layer 22b, and the exposed second adhesive layer 22b is bonded to the side of the covering material 23 opposite to the first adhesive layer 22a side. Finally, the release sheet is peeled off from the light diffusion layer sheet, and the exposed light diffusion layer 30 is bonded to the first glass substrate 41a of the display module 4. Thereby, the touch panel 1A shown in fig. 1 is manufactured.
The touch panel 1A described above has excellent writing feeling with a stylus pen, suppresses glare, and has good visibility of displayed images.
[ second embodiment ]
In the touch panel 1A of the first embodiment, the light diffusion layer 30 is provided at a position adjacent to the display body module 4, but the present invention is not limited thereto, and may be provided at any position between the writing feeling enhancement layer 10 and the display body module 4.
For example, as in the touch panel 1B of the second embodiment shown in fig. 2, the light diffusion layer 30 may be provided between the base film 21 and the cover material 23. In this case, in the touch panel 1A of the first embodiment, the first adhesive layer 22a is replaced with the light diffusion layer 30, and the fourth adhesive layer 22d is provided at a position where the light diffusion layer 30 originally exists. The fourth adhesive layer 22d may have the same configuration as the first adhesive layer 22a, the second adhesive layer 22b, or the third adhesive layer 22 c.
Here, in the touch panel 1B of the present embodiment, the total haze from the writing feeling enhancement layer 10 to the light diffusion layer 30 (the total haze of the writing feeling enhancement layer 10, the base material film 21, and the light diffusion layer 30 in the present embodiment) needs to be 12% or more and 45% or less, and the distance between the light diffusion layer 30 and the color filter 44 needs to be 4mm or less.
The light diffusion layer 30 in the touch panel 1B of the present embodiment is preferably basically the same in configuration as the light diffusion layer 30 in the touch panel 1A of the first embodiment. However, the light-diffusing fine particles in the adhesive composition P are preferably light-diffusing fine particles formed of a silicon-containing compound having an intermediate structure between organic and inorganic materials, such as a silicone resin. The content of the light-diffusing fine particles in the adhesive composition P is preferably 0.01 part by mass or more, particularly preferably 0.1 part by mass or more, and more preferably 0.5 part by mass or more, per 100 parts by mass of the (meth) acrylate polymer (a). The content of the light diffusing fine particles is preferably 15 parts by mass or less, more preferably 12 parts by mass or less, and still more preferably 10 parts by mass or less. Since the content of the light diffusing fine particles is within the above range, the light transmittance of the light diffusing layer 30 is not hindered, and the total haze value can be easily brought into the above range. In addition, sufficient adhesiveness is easily exhibited for other members adjacent to the light diffusion layer 30, and occurrence of defects such as accidental peeling can be prevented.
The touch panel 1B of the present embodiment can be manufactured basically in the same manner as the touch panel 1A of the first embodiment. The light diffusion layer 30 can be laminated on the base film 21 using a light diffusion layer sheet in the same manner as the touch panel 1A of the first embodiment.
The position of the light diffusion layer 30 in the touch panel is not limited to the positions in the touch panel 1A of the first embodiment and the touch panel 1B of the second embodiment. For example, the second adhesive layer 22b or the third adhesive layer 22c in the touch panel 1A of the first embodiment may be replaced with a light diffusion layer. In this case, the light diffusion layer 30 in the touch panel 1A of the first embodiment may be the same adhesive layer as the first to third adhesive layers 22a to 22 c.
For example, the light diffusion layer 30 may be provided between the writing feeling enhancement layer 10 and the base film 21 so as to be adjacent to the writing feeling enhancement layer 10. Such a touch panel can be basically manufactured in the same manner as the touch panel 1A of the first embodiment, but is different in that the writing feeling improving layer 10 is formed on the light diffusion layer 30 after the light diffusion layer 30 is laminated on the base film 21. The light diffusion layer 30 can be laminated on the base film 21 by using a light diffusion layer sheet in the same manner as the touch panel 1A of the first embodiment. In the case where the light diffusion layer 30 is provided between the writing feeling enhancement layer 10 and the base film 21, the light diffusion layer 30 may not have tackiness. In this case, for example, the light diffusion layer 30 may be formed by using a coating composition containing a curable component such as an active energy ray-curable component or a thermosetting component and fine particles, as in the case of the writing feeling enhancement layer 10.
[ third embodiment ]
In the touch panel 1A of the first embodiment, the position detection function is performed by the first touch sensor 24a and the second touch sensor 24b existing outside the display body module 4, but the present invention is not limited thereto, and the display body module may have the position detection function.
For example, as shown in fig. 3, a touch panel 1C according to a third embodiment may have the following configuration: the writing feeling enhancement layer 10, a base film 21 on which the writing feeling enhancement layer 10 is formed, the adhesive layer 22 for bonding the base film 21, a cover material 23 bonded to the base film 21 via the adhesive layer 22, a light diffusion layer 30 having adhesiveness for bonding the cover material 23, and the display body module 5 having a position detection function, which is bonded to the cover material 23 via the light diffusion layer 30, are located on the stylus non-contact side (lower side in fig. 3) of the writing feeling enhancement layer 10.
The display module 5 is not particularly limited as long as it has a color filter and position detection function (touch sensor), and a Liquid Crystal (LCD) module, a Light Emitting Diode (LED) module, an organic electroluminescence (organic EL) module, or the like can be generally used. As an example, fig. 3 shows a liquid crystal module. In the present embodiment, the display body module 5 includes the following configuration: a first glass substrate 51a adjacent to the light diffusion layer 30, a first module adhesive layer 52a located under the first glass substrate 51a, a first polarizing plate 53a located under the first module adhesive layer 52a, a second glass substrate 51b located under the first polarizing plate 53a, a color filter 54 located under the second glass substrate 51b, a liquid crystal layer 55 located under the color filter 54, a second module adhesive layer 52b located under the liquid crystal layer 55, a first touch sensor 56a located under the second module adhesive layer 52b, a third module adhesive layer 52c located under the first touch sensor 56a, a second touch sensor 56b located under the third module adhesive layer 52c, a fourth module adhesive layer 52d located under the second touch sensor 56b, a third glass substrate 51c located under the fourth module adhesive layer 52d, A second polarizing plate 53b positioned under the third glass substrate 51c, and a backlight 57 positioned under the second polarizing plate 53 b.
The touch panel 1C of the present embodiment can be manufactured basically in the same manner as the touch panel 1A of the first embodiment.
[ fourth embodiment ]
In the touch panel 1C of the third embodiment, 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 may be provided at any position between the writing feeling enhancement layer 10 and the display body module 5.
For example, as in the touch panel 1D of the fourth embodiment shown in fig. 4, the light diffusion layer 30 may be provided between the base film 1 and the cover material 23. In this case, in the touch panel 1C of the third embodiment, the adhesive layer 22 is replaced with the light diffusion layer 30, and the light diffusion layer 30 is replaced with the adhesive layer 22. The adhesive layer 22 may have the same configuration as the adhesive layer 22 of the touch panel 1C according to the third embodiment.
The touch panel 1D of the present embodiment can be manufactured basically in the same manner as the touch panel 1B of the second embodiment.
[ fifth embodiment ]
In the touch panels 1A to 1D of the first to fourth embodiments described above, only one covering material 23 is present, but a plurality of covering materials (and adhesive layers) may be provided in order to adjust the distance between the light diffusion layer 30 and the color filter 54 or to adjust the total haze from the writing feeling enhancement layer 10 to the light diffusion layer 30. For example, as in 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 includes the following configuration: the writing feeling enhancement layer 10, a base film 21 which is located on the side (lower side in fig. 5) of the writing feeling enhancement layer 10 which is not in contact with the stylus and on which the writing feeling enhancement layer 10 is formed, a light diffusion layer 30 which is located on the lower side of the base film 21 and has adhesiveness, a first cover material 23a which is bonded to the base film 21 via the light diffusion layer 30, a first adhesive layer 22a which is located on the lower side of the first cover material 23a, a second cover material 23b which is located on the lower side of the first adhesive layer 22a, a second adhesive layer 22b which is located on the lower side of the second cover material 23b, and a display body module 5 which is bonded to the second cover material 23b via the second adhesive layer 22b and has a position detection function. The first covering material 23a may have a level difference due to a printed layer or the like, as in the case of the covering material 23 described above. On the other hand, the covering material other than the first covering material 23a (the second covering material 23b in the present embodiment) does not generally have a level difference due to the printed layer or the like. The fifth touch panel 1E is a modification based on the fourth touch panel 1D, but is not limited thereto.
The position of the light diffusion layer 30 in the touch panel is not limited to the position in the touch panel 1E of the fifth embodiment. For example, in the touch panel 1E of the fifth embodiment, the first adhesive layer 22a or the second adhesive layer 22b may be replaced with the light diffusion layer 30, and the light diffusion layer 30 may be replaced with an adhesive layer similar to the first adhesive layer 22a or the second adhesive layer 22 b.
The number of the covering material and the 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 feeling enhancement layer 10 to the light diffusion layer 30 are within a predetermined range. For example, as the 6 th touch panel 1F shown in fig. 6 described below, three sheets of the cover material and three layers of the adhesive layer may be provided.
The embodiments described above are described for the purpose of facilitating understanding of the present invention, and are not described for limiting the present invention. Therefore, the gist of each element disclosed in the above embodiments also includes all design modifications and equivalents that fall within the technical scope of the present invention.
For example, when the surface of the base film 21 satisfies the writing feeling physical properties, the writing feeling improving layer 10 as the coating layer is not necessary, and in this case, the base film 21 itself becomes the writing feeling improving layer.
(examples)
The present invention will be described more specifically with reference to examples and the like, but the scope of the present invention is not limited to these examples and the like.
[ example 1]
(1) Formation of writing feeling enhancing layer
A coating composition was obtained by mixing 100 parts by mass (in terms of solid content, hereinafter, the same applies to other components) of an organic-inorganic hybrid resin (product name "OPSTAR Z7530" manufactured by Mitsuka chemical industries, Ltd.) as a curable component, 10 parts by mass of normal spherical crosslinked polymethyl methacrylate fine particles having an average particle diameter of 3 μm, and 5 parts by mass of 1-hydroxycyclohexyl phenyl ketone as a photopolymerization initiator. The coating composition was diluted with propylene glycol monomethyl ether to prepare a coating liquid.
A polyester film (product name, manufactured by Toyo Co., Ltd.) having an easy-adhesion layer as a base film
"COSMOSHINE a 4300", thickness: 125 μm) was applied to the side of the easy-adhesion layer with a wire bar #14, and dried at 70 ℃ for one minute. Subsequently, the laminate comprising the writing feeling-improving layer and the base film was obtained by irradiating ultraviolet rays under the following conditions with an ultraviolet ray irradiation apparatus (product name "nitrogen purged small conveyor belt type UV irradiation apparatus CSN 2-40" manufactured by GS-YUASA Corporation) to form the writing feeling-improving layer having a thickness of 5 μm.
[ conditions for ultraviolet irradiation ]
Light source: a high-pressure mercury lamp;
lamp power: 1.4 kW;
conveyor belt speed: 1.2 m/min;
illuminance: 100mW/cm2；
Light amount: 240mJ/cm2。
The thickness of the writing feeling enhancement layer was determined by measuring the total thickness of the laminate using a constant pressure thickness measuring instrument (product name "PG-01J" manufactured by Teclock corporation), and calculating the difference between the total thickness of the obtained laminate and the thickness of the base film as the thickness of the writing feeling enhancement layer.
(2) Formation of light diffusion layer
An acrylic ester copolymer was prepared 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. The molecular weight of the acrylic acid ester copolymer was measured by the following method, and the weight average molecular weight (Mw) was 50 ten thousand.
The weight average molecular weight (Mw) is a weight average molecular weight in terms of polystyrene measured by Gel Permeation Chromatography (GPC) under the following conditions (GPC measurement).
< measurement conditions >
GPC measurement apparatus: HLC-8020 available from Tosoh corporation;
GPC column (run through in the following order): manufactured by Tosoh corporation;
TSK guard column HXL-H；
TSK gel GMHXL(×2)；
TSK gel G2000HXL；
determination of the solvent: tetrahydrofuran;
measurement temperature: at 40 ℃.
100 parts by mass of the acrylate copolymer obtained in the above-mentioned step, 0.25 part by mass of trimethylolpropane-modified toluene diisocyanate (product name "BHS-8515" manufactured by Toyo-chem Co.) as a crosslinking agent, and 0.5 part by mass of spherical silicone fine particles (fine particles formed of a silicon-containing compound having an intermediate structure between inorganic and organic particles) (product name "Tospearl 120" manufactured by Momentive Performance Materials-Japan Co.) having an average particle diameter of 2.0 μm were mixed and diluted with ethyl acetate to obtain a coating liquid of an adhesive composition.
The coating liquid of the adhesive composition obtained above was applied to a release-treated surface of a release sheet (SP-PET 3811 manufactured by Lintec, Inc., thickness: 38 μm) obtained by releasing one surface of a polyethylene terephthalate film with a silicone-based release agent using a knife coater, and then heated at 90 ℃ for one minute to form a light diffusion layer having a thickness of 10 μm, thereby obtaining a light diffusion layer sheet.
The thickness of the light diffusion layer was measured by measuring the total thickness of the light diffusion layer sheet using a constant pressure thickness measuring instrument (manufactured by Teclock, product name "PG-01J"), and the difference between the total thickness of the obtained light diffusion layer sheet and the thickness of the release sheet was calculated as the thickness of the light diffusion layer.
(3) Formation of adhesive layer
100 parts by mass of the acrylate copolymer used for the light diffusion layer was mixed with 0.25 part by mass of trimethylolpropane-modified toluene diisocyanate (product name "BHS-8515" manufactured by Toyo-chem Co.) as a crosslinking agent, and the mixture was diluted with ethyl acetate to obtain a coating liquid of an adhesive composition.
The coating liquid of the adhesive composition obtained above was applied to the release-treated surface of a release sheet (SP-PET 3811 manufactured by Lindelco Ltd., thickness: 38 μm) obtained by releasing a silicone-based release agent on one surface of a polyethylene terephthalate film using a knife coater, and then heated at 90 ℃ for one minute to form an adhesive layer having a thickness of 100 μm, thereby obtaining an adhesive sheet.
The thickness of the adhesive layer was measured by measuring the total thickness of the adhesive sheet using a constant-pressure thickness measuring instrument (manufactured by Telock, trade name "PG-01J"), and the difference between the total thickness of the obtained adhesive sheet and the thickness of the release sheet was calculated as the thickness of the adhesive layer.
(4) Lamination of components
As described below, the respective members are laminated to manufacture a touch panel having the configuration (configuration 1E) shown in fig. 5. The lamination of the respective members was performed manually by using a press roller (2kg, material of the portion in contact with the sample: rubber).
(a) First, a base film in a laminate comprising a writing feeling enhancement layer and a base film is laminated with a light diffusion layer of a light diffusion layer sheet.
(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 was laminated with a first cover material (product name "EAGLE XG" manufactured by Corning corporation, thickness 700 μm).
(c) Subsequently, the first cover material and the adhesive layer (thickness: 100 μm) of the adhesive sheet were laminated. This adhesive layer corresponds to the first adhesive layer 22a in fig. 5.
(d) Subsequently, the release sheet of the adhesive sheet was peeled off from the adhesive layer (first adhesive layer 22a), and the exposed adhesive layer (first adhesive layer 22a) was laminated with a second covering material (product name "EAGLE XG" manufactured by corning corporation, thickness 1100 μm).
(e) Subsequently, the second cover material and the adhesive layer (thickness: 100 μm) of the adhesive sheet were laminated. This adhesive layer corresponds to the second adhesive layer 22b in fig. 5.
(f) Finally, the release sheet of the adhesive sheet was peeled off from the adhesive layer (second adhesive layer 22b), and the exposed adhesive layer (second adhesive layer 22b) was laminated with a display module (resolution: 264ppi) having a distance of 1mm from the color filter to the surface of the display module, thereby obtaining a touch panel having a configuration (configuration 1E) as shown in fig. 5.
[ example 2]
A touch panel was produced in the same manner as in example 1 except that the materials, formulation ratios, and thicknesses of the writing feeling enhancement layer and the light diffusion layer were changed as shown in table 1, and the thickness of the first covering material was changed to 1100 μm, and the thickness of the adhesive agent layer corresponding to the first adhesive agent layer 22a and the thickness of the adhesive agent layer corresponding to the second adhesive agent layer 22b were changed to 400 μm, respectively.
[ examples 3 and 4]
A touch panel was produced in the same manner as in example 1, except that the materials, blending ratios, and thicknesses of the writing feeling enhancement layer and the light diffusion layer were changed as shown in table 1.
[ example 5]
A touch panel was produced in the same manner as in example 1, except that the materials, blending ratios, and thicknesses of the writing feeling enhancement layer and the light diffusion layer were changed as shown in table 1, the configuration of the touch panel was changed to the configuration (configuration 1D) shown in fig. 4, and the thickness of the adhesive layer was changed to 300 μm. The touch panel having the structure shown in fig. 4 is manufactured as follows.
(a) First, a base film in a laminate comprising a writing feeling enhancement layer and a base film is laminated with a light diffusion layer of a light diffusion layer sheet.
(b) Subsequently, the release sheet of the light diffusion layer sheet was peeled off from the light diffusion layer, and the exposed light diffusion layer was laminated with a cover material (product name "EAGLE XG" manufactured by corning corporation, thickness 700 μm).
(c) Subsequently, the above-mentioned covering material and the adhesive layer (thickness 300 μm) of the adhesive sheet were laminated.
(d) Finally, the release sheet of the adhesive sheet was peeled off from the adhesive layer, and the exposed adhesive layer was laminated with a display module (resolution: 264ppi) having a distance of 1mm from the color filter to the surface of the display module, thereby obtaining a touch panel having a configuration (configuration 1D) shown in fig. 4.
[ example 6]
A touch panel was produced in the same manner as in example 5, except that the materials, blending ratios, and thicknesses of the writing feeling enhancement 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 materials, blending ratios, and thicknesses of the writing feeling enhancement 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 materials, blending ratios, and thicknesses of the writing feeling enhancement layer and the light diffusion layer were changed as shown in table 1.
Comparative example 3
A touch panel was produced in the same manner as in example 1, except that the materials, blending ratios, and thicknesses of the writing feeling enhancement layer and the light diffusion layer were changed as shown in table 1, the configuration of the touch panel was changed to the configuration (configuration 1F) shown in fig. 6, the thickness of the first cover material was changed to 1100 μm, and the thickness of the adhesive layer was changed to 300 μm and 200 μm.
Here, the touch panel 1F shown in fig. 6 includes the following configuration: a writing feeling-improving layer 10, a base film 21 which is located on the side of the writing feeling-improving layer 10 which is not in contact with the stylus (lower side in fig. 6) and on which the writing feeling-improving layer 10 is formed, a light diffusion layer 30 which is located on the lower side of the base film 21 and has adhesiveness, a first cover material 23a (thickness: 1100 μm) which is bonded to the base film 21 via the light diffusion layer 30, a first adhesive layer 22a (thickness: 300 μm) which is located on the lower side of the first cover material 23a, a second cover material 23b (thickness: 1100 μm) which is located on the lower side of the first adhesive layer 22a, a second adhesive layer 22b (thickness: 200 μm) which is located on the lower side of the second adhesive layer 22b, a third cover material 23c (thickness: 1100 μm) which is located on the lower side of the third cover material 23c, and a third adhesive layer 22c (thickness: 200 μm) which is located on the lower side of the third cover material 23c, And a display body module 5 bonded to the third cover material 23c via the third adhesive layer 22c and having a position detection function.
The touch panel 1 having the structure shown in fig. 6 is manufactured as follows.
(a) First, a base film in a laminate comprising a writing feeling enhancement layer and a base film is laminated with a light diffusion layer of a light diffusion layer sheet.
(b) Subsequently, the release sheet of the light diffusion layer sheet was peeled off from the light diffusion layer, and the exposed light diffusion layer was laminated with a first cover material (product name "EAGLE XG" manufactured by corning corporation, thickness 1100 μm).
(c) Subsequently, the first cover material and the adhesive layer (thickness 300 μm) of the adhesive sheet were laminated. This adhesive layer corresponds to the first adhesive layer 22a in fig. 6.
(d) Subsequently, the release sheet of the adhesive sheet was peeled off from the adhesive layer (first adhesive layer 22a), and the exposed adhesive layer (first adhesive layer 22a) and a second covering material (product name "EAGLE XG" manufactured by corning corporation, thickness 1100 μm) were laminated.
(e) Subsequently, the second cover material and the adhesive layer (thickness 200 μm) of the adhesive sheet were laminated. This adhesive layer corresponds to the second adhesive layer 22b in fig. 6.
(f) Subsequently, the release sheet of the adhesive sheet was peeled off from the adhesive layer (second adhesive layer 22b), and the exposed adhesive layer (second adhesive layer 22b) was laminated with a third covering material (product name "EAGLE XG" manufactured by corning corporation, thickness 1100 μm).
(g) Subsequently, the third covering material and the adhesive layer (thickness 200 μm) of the adhesive sheet were laminated. This adhesive layer corresponds to the third adhesive layer 22c in fig. 6.
(h) Finally, the release sheet of the adhesive sheet was peeled off from the adhesive layer (third adhesive layer 22c), and the exposed adhesive layer (third adhesive layer 22c) was laminated with a display module (resolution: 264ppi) having a distance of 1mm from the color filter to the surface of the display module, thereby obtaining a touch panel having a configuration (configuration 1F) as shown in fig. 6.
Comparative example 4
A touch panel was produced in the same manner as in example 1, except that the light diffusion layer used in example 1 was changed to the adhesive layer (thickness 10 μm) used in example 1, and the structure of the touch panel was changed to the structure shown in fig. 7 (structure 1G).
Here, the touch panel 1G shown in fig. 7 includes the following configuration: a writing feeling-improving layer 10, a base film 21 on which the writing feeling-improving layer 10 is formed and which is positioned on the side of the writing feeling-improving layer 10 not in contact with a stylus (lower side in fig. 7), and a first adhesive layer 22a positioned below the base film 21
(thickness: 10 μm), a first cover material 23a positioned under the first adhesive layer 22a, a second adhesive layer 22b (thickness: 100 μm) positioned under the first cover material 23a, a second cover material 23b positioned under the second adhesive layer 22b, a third adhesive layer 22c (thickness: 100 μm) positioned under the second cover material 23b, and a display module 5 having a position detection function bonded to the second cover material 23b via the third adhesive layer 22 c.
The touch panel 1G having the structure shown in fig. 7 is manufactured as follows.
(a) First, a base film and an adhesive layer (10 μm in thickness) of an adhesive sheet were laminated on each other in a laminate comprising a writing feeling enhancement layer and the base film. This adhesive layer corresponds to the first adhesive layer 22a in fig. 7.
(b) Subsequently, the release sheet of the adhesive sheet was peeled off from the adhesive layer (first adhesive layer 22a), and the exposed adhesive layer (first adhesive layer 22a) was laminated with a first covering material (product name "EAGLE XG" manufactured by corning corporation, thickness 700 μm).
(c) Subsequently, the first cover material and the adhesive layer (thickness: 100 μm) of the adhesive sheet were laminated. This adhesive layer corresponds to the second adhesive layer 22b in fig. 7.
(d) Subsequently, the release sheet of the adhesive sheet was peeled off from the adhesive layer (second adhesive layer 22b), and the exposed adhesive layer (second adhesive layer 22b) was laminated with a second covering material (product name "EAGLE XG" manufactured by corning corporation, thickness 1100 μm).
(e) Subsequently, the second cover material and the adhesive layer (thickness: 100 μm) of the adhesive sheet were laminated. This adhesive layer corresponds to the third adhesive layer 22c in fig. 7.
(f) Finally, the release sheet of the adhesive sheet was peeled off from the adhesive layer (third adhesive layer 22c), and the exposed adhesive layer (third adhesive layer 22c) was laminated with a display module (resolution: 264ppi) having a distance of 1mm from the color filter to the surface of the display module, thereby obtaining a touch panel having a configuration (configuration 1G) as shown in fig. 7.
[ reference example 1]
A touch panel was produced in the same manner as in example 1, except that the materials, blending ratios, and thicknesses of the writing feeling enhancement layer and the light diffusion layer were changed as shown in table 1.
Here, details of abbreviations and the like described in table 1 are as follows.
A: an organic-inorganic hybrid resin (product name "OPSTAR Z7530" manufactured by Ishikawa chemical industries, Ltd.);
b: a multifunctional urethane acrylate (product name "BEAMSET 575 CB" available from Ishikawa chemical industries, Ltd.);
c: a spherical crosslinked polymethyl methacrylate fine particle 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: a crosslinked polymethyl methacrylate fine particle having a regular spherical shape and an average particle diameter of 1.5 μm (CV value: 23%);
g: 1-hydroxycyclohexyl phenyl ketone (photopolymerization initiator);
h: an acrylate copolymer (Mw: 50 ten thousand) 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: spherical silicone fine particles (fine particles formed of a silicon-containing compound having an intermediate structure of inorganic and organic) having an average particle diameter of 2.0 μm (product name "Tospearl 120" manufactured by Momentive Performance Materials-Japan);
j: spherical polymethyl methacrylate-polystyrene copolymer fine particles having an average particle diameter of 3.5 μm;
k: trimethylolpropane-modified tolylene diisocyanate (product name "BHS-8515" manufactured by Toyo-chem Co., Ltd.) (crosslinking agent).
[ test example 1] (calculation of the distance between the light diffusion layer and the color filter)
In the touch panels manufactured in the examples and the comparative examples, the distance between the light diffusion layer and the color filter is calculated. In addition, as described above, in the display body modules (resolution: 264ppi) used in the examples and comparative examples, the distance from the color filter to the surface of the display body module (surface to which the adhesive layer is applied) was 1 mm. The results are shown in Table 2.
[ test example 2] (measurement of haze value)
The total haze (%) and the internal haze (%) of the touch panels manufactured in examples and comparative examples from the writing feeling improving layer to the light diffusion layer were measured using a haze meter (product name "NDH 2000" manufactured by japan electro-chromic industries) based on JIS K7105. The results are shown in Table 2.
Specifically, the total haze was calculated by measuring the haze of the laminate of the writing feeling enhancement layer, the base film, the light diffusion layer (adhesive layer in comparative example 4), and the release sheet obtained in the production processes of examples and comparative examples, and subtracting the haze of the release sheet from the haze.
Further, the pressure-sensitive adhesive sheets (pressure-sensitive adhesive layer + release sheet) used in examples and comparative examples were attached to the writing feeling improving layer of the laminate, and the haze of the pressure-sensitive adhesive sheet was measured. Then, the internal haze was calculated by subtracting the haze of the adhesive sheet and the haze of the release sheet from the haze.
[ test example 3] (Pen smoothness test)
The touch panels manufactured in examples and comparative examples were mounted on a glass substrate so that the writing feeling enhancement layer side was upward. The tip of a stylus pen (product name "ACK-2003" manufactured by Wacom Co.) having a hard felt tip with a tip diameter of 0.5mm was moved in a direction parallel to the surface of the writing feeling-improving layer while being brought into contact with the surface of the writing feeling-improving layer in a vertical direction (a direction in which the axis of the tip is perpendicular to the surface of the writing feeling-improving layer) under a pressure condition of a load of 3.92N at a speed of 100 mm/min. The stylus pen is attached to a carriage dedicated for measurement, and the carriage is moved to slide the stylus pen on the writing feeling improving layer.
The pen tip resistance during the movement was measured using a universal tester (product name "Tensilon" manufactured by Orientec Co., Ltd.), and a graph of the movement distance (mm) against the pen tip resistance (mN) was obtained. Then, the obtained graph of the moving distance (mm) and the pen point resistance (mN) was fourier-transformed by software (product of Microsoft corporation, software name "Excel") to obtain a frequency (Hz) -amplitude (-) graph. From the frequency (Hz) -amplitude (-) graph, the average value, the maximum value (maximum amplitude value) and the number of peaks (number of amplitudes) of the amplitude in the frequency range of 1 to 2Hz were obtained. The results are shown in Table 2.
[ test example 4] (sensory evaluation of writing feeling)
The touch panels manufactured in examples and comparative examples were mounted on a glass substrate so that the writing feeling enhancement layer side was upward. The panelists evaluated the writing feeling by sliding the tip of a stylus (product name "ACK-2003" manufactured by Wacom corporation) having a hard felt tip with a tip diameter of 0.5mm on the surface of the writing feeling-improving layer.
In the evaluation, a person who had a writing feeling close to that when writing on a paper (manufactured by Kokuyo S & T, product name "Campus note A line no-201A") stacked five sheets of paper (manufactured by Kokuyo S & T, product name "Campus note A line no-201A") with a pencil (manufactured by Mitsubishi Pencil) pressed at about 400g was evaluated as good, and a person who had a deviation from the writing feeling was evaluated as bad. Further, the evaluation was performed by three panelists, all three people felt good as "excellent", all one to two people felt good as "good", and all three people felt bad as "x". The results are shown in Table 2.
[ test example 5] (evaluation of glare)
The entire surface of the display body module (flat panel terminal) of the touch panel manufactured in the examples and comparative examples was displayed with green (RGB values (R, G, B): 0,128,0), and glare was evaluated by visual observation based on the following criteria. The results are shown in Table 2.
Very good: no glare was confirmed.
O: slight glare was confirmed, but there was no practical problem.
X: glare was confirmed.
[ test example 6] (visibility of evaluation display image)
The display body modules (tablet terminals) of the touch panels manufactured in examples and comparative examples were displayed with green color (RGB values (R, G, B): 0,128,0) over the entire surface, and the visibility of the display images was evaluated by visual observation based on the following criteria. The results are shown in Table 2.
Very good: it was confirmed that the visibility of the displayed image was not lowered.
O: it was confirmed that the visibility of the displayed image was slightly reduced (discoloration, blurring, etc.) (in reality)
No problem in use).
X: it was confirmed that the visibility of the displayed image was reduced (discoloration, blurring of the image, etc.).
TABLE 1
Figure BDA0001507378550000381
TABLE 2
Figure BDA0001507378550000391
As is clear from table 2, the touch panel manufactured in the embodiment can suppress glare, and has good visibility of a displayed image and excellent writing feeling using a stylus pen.
Industrial applicability
The image display device having the position detection function of the present invention is suitable as a touch panel having excellent writing feeling and visibility.
Description of the reference numerals
1A, 1B, 1C, 1D, 1E, 1F, 1G-touch panel (image display device with position detection function);
10-writing feeling improvement layer;
21-a substrate film;
22-an adhesive layer;
22 a-a first adhesive layer;
22 b-a second adhesive layer;
22 c-a third adhesive layer;
22 d-a fourth adhesive layer;
23-a cover material;
23 a-a first covering material;
23 b-a second covering material;
23 c-a third covering material;
24 a-a first touch sensor;
24 b-a second touch sensor;
30-a light diffusion layer;
4. 5-display body module;
41a, 51 a-a first glass substrate;
41b, 51 b-a second glass substrate;
41c, 51 c-a third glass substrate;
42-a modular adhesive layer;
52 a-a first module adhesive layer;
52 b-a second module adhesive layer;
52 c-a third module adhesive layer;
52 d-a fourth module adhesive layer;
43a, 53 a-first polarizing plate;
43b, 53 b-second polarizing plate;
44. 54-color filter film;
45. 55-a liquid crystal layer;
56 a-first touch sensor;
56 b-a second touch sensor;
47. 57-backlight.

Claims (7)

1. An image display device having a position detection function, comprising at least:
a writing feeling improving layer contacted by the touch pen,
Display module with color filter film, and
a light diffusion layer provided on the entire surface at an arbitrary position between the writing feeling enhancement layer and the display module,
a total haze from the writing feeling-improving layer to the light diffusion layer is 12% or more and 45% or less,
the distance between the light diffusion layer and the color filter film is less than 4mm,
the writing feeling improving layer contains amorphous fine particles having an average particle diameter of 0.5 to 3 μm or spherical fine particles having an average particle diameter of 1.7 to 15 μm.
2. The image display device with a position detection function according to claim 1, wherein the image display device with a position detection function comprises a base film, and the writing feeling enhancement layer is provided on one surface side of the base film.
3. The image display device with a position detection function according to claim 1, wherein a tip of a stylus pen having a hard felt tip with a tip diameter of 0.5mm is brought into contact with a surface of the writing feeling enhancement layer, which is in contact with the stylus pen, in a vertical direction under a pressure condition of a load of 3.92N, and is moved in any direction parallel to the surface of the writing feeling enhancement layer at a speed of 100 mm/minute to measure a tip resistance, a graph of the obtained movement distance and the tip resistance is subjected to fourier transform, an average value of amplitudes in a range of frequencies of 1 to 2Hz, which is obtained from a frequency-amplitude graph obtained by the transform, is 1.0 or more and 10 or less, and the number of peaks of the amplitudes is 4 or more and 30 or less.
4. The image display device having a position detecting function according to claim 1, wherein the writing feeling enhancement layer is a layer obtained by curing a coating composition containing a curable component and fine particles.
5. The image display device with position detection function according to claim 1, wherein the light diffusion layer is a layer formed of an adhesive composition containing an adhesive component and light diffusion fine particles.
6. The image display device with position detection function of claim 1, wherein the light diffusion layer is disposed adjacent to the display module.
7. The image display device with a position detecting function according to claim 2, wherein the light diffusion layer is provided adjacent to the base material film on which the writing feeling improving layer is provided.
CN201711335916.2A 2017-02-20 2017-12-14 Image display device with position detection function Active CN108459365B (en)

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Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7004498B2 (en) * 2016-12-14 2022-01-21 リンテック株式会社 Writing quality improvement film
JP2020197595A (en) * 2019-05-31 2020-12-10 リンテック株式会社 Light diffusion control film

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103033867A (en) * 2011-10-07 2013-04-10 瀚宇彩晶股份有限公司 Polaroid, display module, touch display device and manufacturing method thereof
CN103364988A (en) * 2012-04-10 2013-10-23 瀚宇彩晶股份有限公司 Touch control display device and manufacturing method thereof
CN104216033A (en) * 2013-05-30 2014-12-17 琳得科株式会社 Anti-dazzling hard coating
CN105128569A (en) * 2015-09-18 2015-12-09 苏州桐力光电技术服务有限公司 Intelligent interactive blackboard
CN106133079A (en) * 2014-03-26 2016-11-16 琳得科株式会社 Cohesiveness compositions, sticker and adhesive sheet

Family Cites Families (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3802842B2 (en) * 1998-07-07 2006-07-26 住友化学株式会社 Upper transparent electrode plate for touch panel and apparatus including the same
JP4082965B2 (en) * 2002-08-28 2008-04-30 リンテック株式会社 Anti-glare hard coat film
JP4264241B2 (en) * 2002-09-26 2009-05-13 富士フイルム株式会社 Antireflection film, antireflection film, and image display device
JP4054670B2 (en) * 2002-12-13 2008-02-27 富士フイルム株式会社 Polarizing plate and liquid crystal display device
US7595789B2 (en) * 2003-07-03 2009-09-29 Kimoto Co., Ltd. Transmission screen
TW200745923A (en) * 2005-10-20 2007-12-16 Nitto Denko Corp Transparent conductive laminate body and touch panel equipped with above
JP2007249191A (en) * 2006-02-17 2007-09-27 Fujifilm Corp Optical film, antireflection film, polarizing plate and image display device
TWI322281B (en) * 2007-04-04 2010-03-21 Eternal Chemical Co Ltd Thin and flexible light guide element
TWI607231B (en) * 2007-07-04 2017-12-01 琳得科股份有限公司 Hard coat film
JP2009020288A (en) * 2007-07-11 2009-01-29 Sony Corp Antiglare film, method of manufacturing the same, polarizer, and display device
KR101447311B1 (en) * 2007-09-20 2014-10-06 도요보 가부시키가이샤 Adhesive sheet, upper electrode for touch panel, and image display device
JP2009151476A (en) * 2007-12-19 2009-07-09 Nof Corp Surface material for pen input device, and pen input device having the same
JP5149052B2 (en) * 2008-03-28 2013-02-20 リンテック株式会社 Anti-glare hard coat film and polarizing plate using the same
CN101546005A (en) * 2008-03-28 2009-09-30 琳得科株式会社 Optical laminate for plasma display
JP2012008333A (en) * 2010-06-24 2012-01-12 Sumitomo Chemical Co Ltd Light-diffusing polarizing plate and liquid crystal display device
JP5277273B2 (en) * 2011-03-14 2013-08-28 富士フイルム株式会社 Manufacturing method of optical film
JP5918701B2 (en) * 2012-10-17 2016-05-18 株式会社ダイセル Transparent film, method of use thereof, and touch panel
JP6199605B2 (en) * 2013-05-27 2017-09-20 日東電工株式会社 Hard coat film and hard coat film roll
JP6151611B2 (en) 2013-09-10 2017-06-21 株式会社ダイセル Transparent tactile film and method for producing the same
KR102262757B1 (en) * 2014-03-11 2021-06-09 다이니폰 인사츠 가부시키가이샤 Touch panel, display device, optical sheet, method for selecting optical sheet, and method for manufacturing optical sheet
JP6349126B2 (en) * 2014-03-31 2018-06-27 株式会社ダイセル Transparent laminated film for pen input device and method for producing the same
JP6585342B2 (en) * 2014-11-19 2019-10-02 住友化学株式会社 Anti-glare film, anti-glare polarizing plate and image display device

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103033867A (en) * 2011-10-07 2013-04-10 瀚宇彩晶股份有限公司 Polaroid, display module, touch display device and manufacturing method thereof
CN103364988A (en) * 2012-04-10 2013-10-23 瀚宇彩晶股份有限公司 Touch control display device and manufacturing method thereof
CN104216033A (en) * 2013-05-30 2014-12-17 琳得科株式会社 Anti-dazzling hard coating
CN106133079A (en) * 2014-03-26 2016-11-16 琳得科株式会社 Cohesiveness compositions, sticker and adhesive sheet
CN105128569A (en) * 2015-09-18 2015-12-09 苏州桐力光电技术服务有限公司 Intelligent interactive blackboard

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