KR102410171B1 - Film for increasing a feel of writing - Google Patents

Abstract

An object of the present invention is to provide a writing feeling improving film capable of effectively reproducing the writing feeling when writing on paper with a pencil by stably controlling the writing vibration within a predetermined range.
As a means for solving these problems, a writing feeling improving film for a touch panel comprising a base film and a writing feeling improving layer, the writing feeling improving layer comprising an active energy ray-curable resin as (A) component, and (B) component It consists of a cured product of the composition for forming a writing feeling improving layer containing a filler, and the filler as component (B) contains amorphous silica particles, and the arithmetic average particle diameter of the amorphous silica particles is set to a value within the range of 0.5 to 3 μm. , and the Cv value of the amorphous silica particles is set to a value within the range of 50 to 200%.

Description

Film for improving writing feeling

The present invention relates to a writing feeling improving film for a touch panel applied to the surface of a touch panel in order to improve the writing feeling with a touch pen.

In particular, it relates to a writing feeling improving film capable of effectively reproducing the feeling of writing on paper with a pencil by stably controlling the writing vibration within a predetermined range.

BACKGROUND ART Conventionally, in various electronic devices, a touch panel serving as both a display device and an input means is widely used.

In particular, in recent years, a pen input type touch panel using a touch pen as an input means has begun to spread, and the use in smart phones, electronic papers, tablet PCs, pen tablets, organic devices, and the like is rapidly expanding.

However, since the display module of the touch panel is generally hard, the writing feeling by the touch pen is greatly different from the writing feeling when writing on paper with a pencil, and it is difficult to say that it is good.

Then, in order to improve the writing feeling with a touch pen, the film for applying to the surface of a touch panel is examined (for example, refer patent documents 1-2).

That is, in Patent Document 1, a polyfunctional (meth)acrylate and an organic and/or inorganic filler are included in the ultraviolet curable resin composition in a plastic film. An anti-glare hard coat film formed by applying an ultraviolet curable resin composition comprising at least one selected from the group consisting of , 1-butanol and irradiating ultraviolet rays is disclosed.

In addition, in Patent Document 2, a protective film having a thickness of 0.1 to 2 mm laminated on the touch surface of the touch input device provided on the display surface of the display, the surface layer of the protective film serving as the new touch surface is essentially transparent and has self-healing properties and A protective film made of a soft synthetic resin having abrasion resistance is disclosed.

Japanese Patent Application Laid-Open No. 2012-126804 (Scope of Claims, etc.) Japanese Patent Application Laid-Open No. 6-180628 (Scope of Claims, etc.)

However, although the anti-glare hard coat film and the like described in Patent Documents 1 and 2 were able to improve abrasion resistance and self-healing properties in the case of scratches to some extent, vibration generated between the pen and the touch pen when taking notes. (hereinafter, sometimes referred to as “writing vibration”) is significantly different from the writing vibration when writing on paper with a pencil, so that there is a problem that the writing feeling is insufficient.

Therefore, as a result of intensive studies, the present inventors have found that in a writing feeling improving film comprising a base film and a writing feeling improving layer, as a composition for forming a writing feeling improving layer for forming a writing feeling improving layer, an active energy ray-curable resin; By using the composition containing the amorphous silica particle which has a predetermined arithmetic mean particle diameter and Cv value, it discovered that these problems could be solved, and this invention was completed.

That is, an object of the present invention is to provide a writing feeling improving film capable of effectively reproducing the writing feeling when writing on paper with a pencil by stably controlling the writing vibration within a predetermined range.

According to the present invention, there is provided a writing feeling improving film for a touch panel comprising a base film and a writing feeling improving layer,

The writing feeling improving layer is composed of a cured product of a composition for forming a writing feeling improving layer comprising an active energy ray-curable resin as a component (A) and a filler as a component (B);

(B) the filler as a component contains amorphous silica particles,

Let the arithmetic mean particle diameter of the amorphous silica particles be a value within the range of 0.5 to 3 μm,

There is provided a writing feeling improving film characterized in that the Cv value of the amorphous silica particles is within the range of 50 to 200%, and the above-described problem can be solved.

That is, according to the writing feeling improving film of the present invention, as a composition for forming a writing feeling improving layer for forming the writing feeling improving layer, the composition comprising an active energy ray-curable resin and amorphous silica particles having a predetermined arithmetic mean particle diameter and Cv value By using , it is possible to stably control the handwriting vibration, effectively reproducing the feeling of writing on paper with a pencil.

Further, in constituting the writing feeling improving film of the present invention, the blending amount of the amorphous silica particles as component (B) is set to a value within the range of 5 to 25 parts by weight based on 100 parts by weight of the active energy ray-curable resin as component (A). it is preferable

By configuring in this way, the writing feeling when writing on paper with a pencil can be more effectively reproduced, and the occurrence of glare can be suppressed more effectively.

Further, in constituting the writing feeling improving film of the present invention, it is preferable that the arithmetic mean roughness Ra in the writing feeling improving layer be set to a value within the range of 0.05 to 0.5 µm.

By configuring in this way, it is possible to more effectively reproduce the feeling of writing on paper with a pencil.

Further, in constructing the writing feeling improving film of the present invention, the nib of a touch pen having a hard felt core having a nib diameter of 0.5 mm is applied to the surface of the writing feeling enhancing layer, and the axial core of the touch pen is the film surface of the writing feeling improving film The nib sliding when the nib resistance is measured by moving the touch pen in an arbitrary direction parallel to the film surface of the writing feeling improvement film at a speed of 100 mm/min while making contact under a pressure condition of 3.92N load to be perpendicular to It is preferable to make the coefficient into a value within the range of 0.05 to 0.5.

By configuring in this way, it is possible to more effectively reproduce the feeling of writing on paper with a pencil.

Further, in constituting the writing feeling improving film of the present invention, it is preferable to set the haze value to a value within the range of 1 to 40%.

By configuring in this way, the writing feeling when writing on paper with a pencil can be more effectively reproduced, and generation of glare can be more effectively suppressed.

Further, in constituting the writing feeling improving film of the present invention, the thickness of the writing feeling improving layer is preferably set to a value within the range of 0.1 to 50 µm.

By configuring in this way, the writing feeling when writing on paper with a pencil can be more effectively reproduced, and generation of glare can be more effectively suppressed.

Further, in constituting the writing feeling improving film of the present invention, it is preferable to provide an adhesive layer on the surface on the opposite side to the side on which the writing feeling improving layer in the base film is located.

By configuring in this way, it can be easily applied to the surface of a touch panel.

1(a) to 1(b) are views provided to explain the configuration of the writing feeling improving film of the present invention.
2 is a view provided to explain a method for measuring pen tip resistance.
3A to 3B are a movement distance (mm)-nib resistance (mN) chart, and a frequency (Hz)-amplitude (-) chart in the writing feeling improvement film of Example 2 drawings provided for
4 is a view provided to explain a display device with a touch panel to which the writing feeling improving film of the present invention is applied.
5A to 5B are a movement distance (mm)-nib resistance (mN) chart, and a frequency (Hz)-amplitude (-) chart in the writing feeling improvement film of Comparative Example 1 drawings provided for
6A to 6B are a movement distance (mm)-nib resistance (mN) chart, and a frequency (Hz)-amplitude (-) chart in the writing feeling improvement film of Comparative Example 6 drawings provided for
7(a) to 7(b) are provided to show the movement distance (mm)-nib resistance (mN) chart, and the frequency (Hz)-amplitude (-) chart when writing on paper with a pencil drawing to do.

An embodiment of the present invention provides a writing feeling improving film 1 for a touch panel including a base film 20 and a writing feeling improving layer 10 as shown in FIG. 1A ,

The writing feeling improving layer 10 is composed of a cured product of a composition for forming a writing feeling improving layer comprising an active energy ray-curable resin as a component (A) and a filler as a component (B);

(B) the filler as a component contains amorphous silica particles,

The arithmetic mean particle diameter of the amorphous silica particles is set to a value within the range of 0.5 to 3 μm, and

A writing feeling improving film (1) characterized in that the Cv value of the amorphous silica particles is within the range of 50 to 200%.

Hereinafter, it will be described in detail with reference to the enemy drawings.

1. Handwriting improvement layer

(1) Composition for forming a writing feeling improving layer

The writing feeling improving layer in the writing feeling improving film of the present invention is composed of a cured product of a composition for forming a writing feeling improving layer comprising at least an active energy ray-curable resin as component (A) and a filler as component (B). do it with

Hereinafter, each component included in the composition for forming a writing feeling improving layer will be described.

(1)-1 (A) component: active energy ray-curable resin

The type of active energy ray-curable resin as component (A) included in the composition for forming a writing feeling improving layer is not particularly limited, and can be selected from conventionally known ones, and an energy ray-curable monomer, oligomer, resin, or mixture thereof can be heard

More specifically, it is preferable to use a polyfunctional (meth)acrylic monomer or a (meth)acrylate-based prepolymer, and from the viewpoint of making the abrasion resistance of the resulting writing feeling improving layer more excellent, the polyfunctional (meth)acrylic monomer is used. It is more preferable to use

Moreover, as a polyfunctional (meth)acrylic-type monomer, it is preferable that it is a bifunctional or more than bifunctional polyfunctional (meth)acrylic-type monomer which has two or more (meth)acryloyl groups in a molecule|numerator, From a viewpoint of making it more excellent in abrasion resistance, 3 It is more preferable that it is functional or more, and it is especially preferable that it is 5 functional or more. On the other hand, from the viewpoint of suppressing curl of the writing feeling improving film, the polyfunctional (meth)acrylic monomer is preferably 20 functional or less, more preferably 12 functional or less, particularly preferably 9 functional or less.

Moreover, it is preferable that a polyfunctional (meth)acrylic-type monomer is a thing of molecular weight 1000 or less from a compatible viewpoint with another component.

In addition, as specific examples of the polyfunctional (meth)acrylic monomer, for example, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acryl rate, polyethylene glycol di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, caprolactone-modified dicyclopentenyl di (meth) acrylate, ethylene oxide Modified phosphoric acid di(meth)acrylate, allylated cyclohexyldi(meth)acrylate, isocyanurate di(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol tri(meth)acryl rate, propionic acid modified dipentaerythritol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, propylene oxide modified trimethylolpropane tri(meth)acrylate, tris(acryloxyethyl)isocyanurate, propionic acid Modified dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, caprolactone modified dipentaerythritol hexa(meth)acrylate, etc. are mentioned.

Moreover, these may be used individually by 1 type, and may be used in combination of 2 or more type.

Moreover, as a (meth)acrylate type prepolymer, a polyester acrylate type, an epoxy acrylate type, a urethane acrylate type, a polyol acrylate type, etc. are mentioned, for example.

Here, as the polyester acrylate-based prepolymer, for example, by esterifying the hydroxyl groups of a polyester oligomer having hydroxyl groups at both terminals obtained by condensation of polyhydric carboxylic acid and polyhydric alcohol with (meth)acrylic acid, or It can obtain by esterifying the hydroxyl group of the terminal of the oligomer obtained by adding alkylene oxide to carboxylic acid with (meth)acrylic acid.

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

In addition, a urethane acrylate type prepolymer can be obtained by reaction of polyether polyol or polyester polyol, and polyisocyanate, for example.

Moreover, a polyol acrylate type prepolymer can be obtained by esterifying the hydroxyl group of polyether polyol with (meth)acrylic acid.

Moreover, these prepolymers may be used individually by 1 type, may be used in combination of 2 or more type, and may be used together with the polyfunctional (meth)acrylate type monomer mentioned above.

(1)-2 (B) Component: Filler

(i) kind

In the present invention, the filler as component (B) contained in the composition for forming a writing feeling improving layer contains silica particles.

The reason for this is that if the silica particles have a sufficiently large Cv value, the uneven shape of the surface of the writing feeling improving layer becomes more complicated, so that the writing feeling when writing on paper with a pencil can be effectively reproduced.

Moreover, even if the arithmetic mean particle diameter is small, it is easy to obtain a writing feeling characteristic, and it is because generation|occurrence|production of glare can also be effectively suppressed.

Moreover, as another filler, you may use together the particle|grains which consist of titania, zirconia, a tin oxide, indium oxide, cadmium oxide, antimony oxide, etc., for example.

(ii) shape

Moreover, it is characterized by making the shape of a silica particle into an irregular shape.

The reason for this is that when amorphous silica particles are used, for example, compared to the case where spherical silica particles are used, not only the Cv value is increased, but also the protrusions on the surface of the writing feeling improving layer correspond to the irregular shape of the filler. This is because it is easy to obtain a writing feeling characteristic.

In addition, in the present invention, "indeterminate" means a shape having a number of irregular corners or surfaces, not a regular shape such as a spherical shape or an elliptical shape.

(iii) arithmetic mean particle diameter

Moreover, it is characterized by making the arithmetic mean particle diameter of amorphous silica particles into a value within the range of 0.5-3 micrometers.

The reason for this is that, when the arithmetic mean particle diameter is less than 0.5 μm, the surface of the writing feeling improving layer becomes smooth, and it may be difficult to effectively reproduce the writing feeling when writing on paper with a pencil. On the other hand, when the arithmetic mean particle diameter exceeds 3 μm, the protrusions on the surface of the writing feeling improving layer become too high to overcome with human pen pressure, so it is necessary to effectively reproduce the writing feeling when writing on paper with a pencil. Because there are times when it becomes difficult. Alternatively, since an optical action with the pixel of the display is likely to occur, glare may easily occur.

Therefore, it is more preferable to set the lower limit of the arithmetic mean particle diameter of amorphous silica particles to a value of 0.8 µm or more, and even more preferably set it to a value of 1 µm or more.

Moreover, it is more preferable to make the upper limit of the arithmetic mean particle diameter of amorphous silica particles into a value of 2.5 micrometers or less, and it is more preferable to set it as a value of 2 micrometers or less.

(iv) Cv value

Moreover, it is characterized by setting the Cv value of the amorphous silica particles to a value within the range of 50 to 200%.

The reason for this is that, when the Cv value is less than 50%, the uneven shape of the surface of the writing feeling improving layer becomes monotonous, making it difficult to obtain sufficient writing feeling characteristics in some cases. On the other hand, when the Cv value exceeds 200%, the number of particles that do not contribute to the writing feeling increases, the required amount of particles increases, and glare tends to occur in some cases.

Accordingly, the lower limit of the Cv value of the amorphous silica particles is more preferably 60% or more, and still more preferably 70% or more.

Moreover, it is more preferable to make the upper limit of the Cv value of amorphous silica particles into a value of 150 % or less, and it is more preferable to set it as a value of 100 % or less.

(v) compounding amount

Moreover, it is preferable to make the compounding quantity of amorphous silica particle into the value within the range of 5-30 weight part with respect to 100 weight part of active energy ray-curable resins as (A) component.

The reason for this is that when the blending amount is less than 5 parts by weight, the ratio of irregularities on the surface of the writing feeling improving layer decreases, making it difficult to effectively reproduce the writing feeling when writing on paper with a pencil. to be. On the other hand, when such a compounding quantity becomes a value exceeding 30 weight part, it is because it may become easy to generate|occur|produce glare easily, or a haze value may become large excessively, and the visibility of the display image of a display may fall easily too much.

Therefore, it is more preferable to make the lower limit of the compounding quantity of amorphous silica particles into a value 8 weight part or more, and it is more preferable to set it as a value 10 weight part or more.

Moreover, it is more preferable to make the upper limit of the compounding quantity of amorphous silica particles into a value 20 weight part or less, and it is more preferable to set it as a value 15 weight part or less.

(1)-3 (C) component: leveling agent

Moreover, it is preferable that the composition for writing feeling improvement layer formation contains a leveling agent as (C)component.

This is because by containing a leveling agent, it can suppress effectively that a linear defect, nonuniformity, etc. generate|occur|produce in the surface of the writing feeling improvement layer obtained, and can control thickness uniformly.

As a result, it is possible to more effectively reproduce the feeling of writing on paper with a pencil.

Moreover, as a kind of leveling agent, a silicone type leveling agent, a fluorine type leveling agent, an acrylic type leveling agent, a vinyl type leveling agent, etc. are mentioned, for example, Among them, from a viewpoint of leveling property and compatibility with other components, a silicone type A leveling agent and a fluorine-type leveling agent are preferable.

Moreover, a leveling agent may be used individually by 1 type, and may be used in combination of 2 or more type.

Moreover, as a silicone leveling agent, it is preferable that they are polydimethylsiloxane or modified|denatured polydimethylsiloxane, and it is especially preferable that it is polydimethylsiloxane.

Moreover, as a fluorine-type leveling agent, it is preferable that it is a compound which has a perfluoroalkyl group or a fluorinated alkenyl group in a main chain or a side chain, As a commercial item, BYK-340 manufactured by Bikchemi Japan Co., Ltd., Futagent manufactured by Neos Co., Ltd. 650A, Megapack RS-75 manufactured by DIC Corporation, V-8FM manufactured by Osaka Yuki Chemical Co., Ltd., etc. are mentioned.

Moreover, as a compounding quantity of a leveling agent, it is preferable that it is a value within the range of 0.001-10 weight part normally with respect to 100 weight part of active energy ray-curable resins as (A) component, It is more preferable that it is a value within the range of 0.005-5 weight part, More preferably, it is a value within the range of 0.01 to 3 parts by weight.

(1)-4 (D) Component: Photoinitiator

In addition, from the viewpoint of stably curing the writing feeling improving layer, it is preferable that the composition for forming the writing feeling improving layer contains a photopolymerization initiator as component (D).

Examples of the type of the photoinitiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylaminoaceto. Phenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxy Cyclohexylphenylketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propan-1-one, 4-(2-hydroxyethoxy)phenyl-2(hydroxy- 2-propyl) ketone, benzophenone, p-phenylbenzophenone, 4,4'-diethylaminobenzophenone, dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 2-aminoanthraquinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyl dimethyl ketal, acetophenone dimethyl ketal; p-dimethylaminobenzoic acid ester etc. are mentioned.

Moreover, these may be used individually by 1 type, and may be used in combination of 2 or more type.

Moreover, as a compounding quantity of a photoinitiator, it is preferable to set it as the value within the range of 0.2-10 weight part normally with respect to 100 weight part of active energy ray-curable resins as (A) component.

(1)-5 Preparation of a composition for forming a writing feeling improving layer

In addition, the composition for forming a writing feeling improving layer can be prepared by adding the above-mentioned components (A) to (D), etc., and dissolving or dispersing it in a suitable solvent as needed.

At this time, as a component other than (A)-(D) component, an antistatic agent, surfactant, antioxidant, a ultraviolet absorber, a silane-type coupling agent, a light stabilizer, an antifoamer, etc. can be added, for example.

Moreover, as a solvent to be used, For example, Alcohol, such as methanol, ethanol, isopropanol, n-butanol, isobutanol, 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, etc. are mentioned.

(2) thickness

In addition, it is preferable to set the thickness of the writing feeling improving layer to a value within the range of 0.1 to 50 µm.

The reason for this is that, when the thickness is less than 0.1 mu m, it may be difficult to ensure sufficient writing feeling characteristics. On the other hand, when this thickness becomes a value exceeding 50 micrometers, it is because it may become easy to generate|occur|produce curl in the writing feeling improvement film.

Therefore, it is more preferable to set the lower limit of the thickness of the writing feeling improving layer to a value of 1 µm or more, and even more preferably set it to a value of 3 µm or more.

Moreover, it is more preferable to set the upper limit of the thickness of the writing feeling improving layer to a value of 20 micrometers or less, and it is more preferable to set it as a value 10 micrometers or less.

2. Base film

Although it does not restrict|limit especially as a kind of base film, For example, Polyester films, such as polyethylene terephthalate, polybutylene terephthalate, and polyethylenenaphthalate, Polyolefin films, such as a polyethylene film and a polypropylene film, Cellophane, diacetyl Cellulose film, triacetyl cellulose film, acetyl cellulose butyrate film, polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene-vinyl acetate copolymer film, polystyrene film, polycarbonate film, polymethylpentene film, poly Sulfone film, polyetheretherketone film, polyethersulfone film, polyetherimide film, fluororesin film, polyamide film, acrylic resin film, polyurethane resin film, norbornene polymer film, cyclic olefin polymer film, cyclic conjugated film Plastic films, such as a diene-type polymer film and a vinyl alicyclic hydrocarbon polymer film, or those laminated|multilayer films are mentioned.

Especially, a polyethylene terephthalate film, a polycarbonate film, a norbornene-type polymer film, etc. are preferable from points, such as mechanical strength.

Moreover, in a base film, in order to improve adhesiveness with the layer provided on the surface, it is preferable to surface-treat to one side or both surfaces by a primer treatment, an oxidation method, an unevenness|corrugation method, etc.

Moreover, it is preferable to set it as the value within the range of 15-300 micrometers, and, as for the thickness of a base film, it is more preferable to set it as the value within the range of 30-200 micrometers.

3. Adhesive layer

Moreover, as shown in FIG.1(b), it is preferable to provide the adhesive layer 30 in the surface on the opposite side to the side in which the writing feeling improvement layer 10 in the base film 20 is located.

As an adhesive which comprises such an adhesive layer, well-known adhesives, such as an acrylic adhesive, a rubber-type adhesive, and a silicone adhesive, can be used, for example.

4. Characteristics

(1) Arithmetic mean roughness Ra

In addition, it is preferable to set the arithmetic mean roughness Ra in the writing feeling improving layer of the writing feeling improving film to a value within the range of 0.05 to 0.5 µm.

The reason for this is that when the arithmetic mean roughness Ra is less than 0.05 mu m, there is no protrusion sufficient to sufficiently vibrate the nib in relation to the human pen pressure. As a result, it becomes difficult to control the handwriting vibration within a predetermined range, and it becomes difficult to effectively reproduce the writing feeling when writing on paper with a pencil. Further, even when gentle unevenness is formed, the arithmetic mean roughness Ra is less than 0.05 µm. On the other hand, when this arithmetic mean roughness Ra becomes a value exceeding 0.5 micrometer, too large protrusion exists in relation to a person's pen pressure. As a result, it becomes difficult to control the handwriting vibration within a predetermined range, and it is sometimes difficult to effectively reproduce the writing feeling when writing on paper with a pencil.

Accordingly, the lower limit of the arithmetic mean roughness Ra in the writing feeling improving layer of the writing feeling improving film is more preferably 0.15 µm or more, and still more preferably 0.22 µm or more.

In addition, the upper limit of the arithmetic mean roughness Ra in the writing feeling improving layer of the writing feeling improving film is more preferably 0.4 µm or less, and still more preferably 0.3 µm or less.

(2) Haze value

Moreover, it is preferable to make the haze value of the writing feeling improvement film into the value within the range of 1 to 40%.

The reason for this is that when the haze value is less than 1%, the density of the projections on the surface of the writing feeling improving layer becomes excessively small. As a result, it becomes difficult to control the handwriting vibration within a predetermined range, and it is sometimes difficult to reproduce the feeling of writing on paper with a pencil. On the other hand, when such a haze value becomes a value exceeding 40 %, it is because it may become easy to generate|occur|produce glare or the visibility of the display image of a display may fall easily too much.

Therefore, the lower limit of the haze value of the writing feeling improving film is more preferably set to a value of 8% or more, and still more preferably set to a value of 10% or more.

Further, the upper limit of the haze value of the writing feeling improving film is more preferably 35% or less, and still more preferably 30% or less.

Here, the mutual complementary relationship between arithmetic mean roughness Ra and a haze value is demonstrated.

First, the value of the arithmetic mean roughness Ra tends to be influenced by the presence of large protrusions. That is, it is possible to determine whether or not there is a protrusion having a height that contributes to the writing feeling characteristic by the arithmetic mean roughness Ra.

However, when only the arithmetic mean roughness Ra is used as an index, the magnitude of the density of projections cannot be discriminated, and thus it becomes difficult to reliably obtain a writing feeling characteristic.

On the other hand, a haze value is a numerical value linking with a processus|protrusion density, and when a processus|protrusion density is large, a haze value will become large.

Accordingly, by specifying the haze value to be greater than or equal to a predetermined value, it is possible to indirectly define the density of the projections contributing to the writing feeling characteristic.

However, when only the haze value is used as an index, the height of the projections cannot be discriminated, so it becomes difficult to reliably obtain the writing feeling characteristics.

For the above reasons, by defining both the arithmetic mean roughness Ra and the haze value, it becomes possible to effectively define the height and density of the projections required to obtain excellent writing feeling characteristics, respectively.

(3) Characteristics of writing feeling

(3)-1 nib sliding coefficient

In addition, as shown in Fig. 2, with respect to the surface of the writing feeling improving layer 10 in the writing feeling improving film 1, the diameter of the nib 52 is 0.5 mm of the touch pen 50 provided with a hard felt core. While bringing the pen tip 52 into contact with the pressure condition of a load of 3.92 N (400 gf) so that the axial center of the touch pen 50 is perpendicular to the film surface of the writing feeling improvement film 1, the touch pen 50 is brought into contact with the writing feeling improvement film ( It is preferable to set the nib sliding coefficient to a value within the range of 0.05 to 0.5 when the nib resistance is measured by moving it in an arbitrary one direction parallel to the film plane of 1) at a speed of 100 mm/min.

The reason for this is that when the nib sliding coefficient is less than 0.05, the nib becomes excessively slippery, and the controllability of the nib tends to deteriorate, making it difficult to reproduce the feeling of writing on paper with a pencil. Because there are cases. On the other hand, when the nib sliding coefficient exceeds 0.5, the nib tends to be caught excessively, conversely, the controllability of the nib tends to decrease, making it difficult to reproduce the feeling of writing on paper with a pencil. because there is

Accordingly, the lower limit of the nib sliding coefficient is more preferably set to a value of 0.17 or more, and still more preferably set to a value of 0.19 or more.

Further, the upper limit of the nib sliding coefficient is more preferably set to a value of 0.3 or less, and still more preferably set to a value of 0.25 or less.

In addition, in the present invention, "nib resistance" means the resistance applied to the pen tip when the touch pen is moved under the above-described conditions.

In the present invention, the "nib sliding coefficient" means a value obtained by dividing the average value of the maximum and minimum values of the "nib sliding resistance" by the load (3.92N).

In the present invention, "nib sliding resistance" refers to the movement distance (mm) - nib resistance (mN) chart, when the nib starts to move, the influence of the initial resistance force of the nib converges, and the nib It means the resistance of the nib when it enters this stable sliding state.

Therefore, for example, in the case of the travel distance (mm)-nib resistance (mN) chart in the writing feeling improvement film of Example 2 shown in FIG. Since it is small, the nib resistance force in the range of 30 mm or more of the movement distance becomes the nib sliding resistance force.

In addition, although the upper limit of the movement distance when specifying the nib sliding resistance is not particularly limited, in consideration of the fluctuation of the value due to frictional heat of the nib, etc., it is usually a position 50 mm from the point where the influence of the nib initial resistance force converges. It is preferable to

Moreover, as described above, although the surface shape suitable for the writing feeling characteristics can be defined by the arithmetic mean roughness Ra and the haze value, it is also necessary to consider the influence of the surface material and the like on the actual writing feeling characteristics.

For example, in the case of a material having high sliding properties and in the case of a material having difficulty in slipping, even if the surface shape of the writing feeling improving layer is the same, the writing feeling characteristics are significantly different.

Compensating for this is the nib sliding coefficient. Based on the nib sliding coefficient, it is possible to grasp the total force applied to the nib.

Here, an example is given and it demonstrates more concretely about the measuring method of pen nib resistance.

That is, first, as shown in FIG. 2 , the writing feeling improving film 1 as a measurement object is fixed to the upper surface of the glass plate 40 so that the writing feeling improving layer 10 is on the upper side.

Next, after the measurement-only cart 70 is disposed so as to exceed the writing feeling improvement film 1, the through-hole 72 extending in the vertical direction provided in the measurement-only cart 70 is provided with a touch pen ( 50) is inferred.

Next, the weight 60 is fixed to the touch pen 50 , and the nib 52 is brought into contact with the surface of the writing feeling improving layer 10 under a pressure condition of a load of 3.92 N.

Next, using a detector 100 such as AUTOGRAPH AG-IS 500N manufactured by Shimadzu Corporation, for example, the tension string 90 fixed to the measurement-only bogie 70 is attached to the pulley 80 ), the nib resistance is measured while pulling at a rate of 100 mm/min in the direction D parallel to the film plane.

In addition, by setting the pressure condition higher than the pressure condition in normal writing with a load of 3.92 N, the force of pressing the pen tip 52 against the writing feeling improving layer 10 becomes stronger, so that the It becomes possible to respond to the concavo-convex shape more sensitively, and furthermore, it becomes possible to detect even a slight difference in the concavo-convex shape of the writing feeling improving layer 10 .

(3)-2 Pen tip sliding resistance

In addition, for the same reason as the above-mentioned nib sliding coefficient is prescribed, it is preferable to set the average value of the nib sliding resistance to a value within the range of 500 to 1000 mN.

Accordingly, the lower limit of the average value of the nib sliding resistance is more preferably 520 mN or more, and still more preferably 560 mN or more.

Further, the upper limit of the average value of the nib sliding resistance is more preferably set to a value of 800 mN or less, and still more preferably set to a value of 700 mN or less.

In addition, the average value of the nib sliding resistance means a value obtained by taking the sum of the maximum and minimum values of all the nib sliding resistances existing in the section in a predetermined moving distance section in which the nib sliding resistance is stable, and dividing by the number of them.

Further, the difference between the maximum value and the minimum value of the nib sliding resistance is preferably set to a value within the range of 10 to 300 mN.

The reason for this is that when the value of such a difference becomes less than 10 mN, the writing vibration becomes excessively small, and it may be difficult to reproduce the writing feeling when writing on paper with a pencil. On the other hand, if the value of this difference exceeds 300 mN, the writing vibration becomes excessively large, and conversely, it may be difficult to reproduce the writing feeling when writing on paper with a pencil.

Accordingly, the lower limit of the difference between the maximum value and the minimum value of the nib sliding resistance is more preferably 75 mN or more, more preferably 95 mN or more, and particularly preferably 120 mN or more.

The upper limit of the difference between the maximum value and the minimum value of the nib sliding resistance is more preferably 200 mN or less, and still more preferably 150 mN or less.

(3)-3 Characteristics in the frequency domain

(i) Amplitude in the frequency range of 1 to 2 Hz

In addition, the movement distance (mm) - nib resistance (mN) chart as shown in Fig. 3 (a) described above is obtained by Fourier transform using, for example, Excel (registered trademark) in Fig. 3 (b) In the frequency (Hz)-amplitude (-) chart as shown in , it is preferable that the average value of the amplitudes in the frequency range of 1 to 2 Hz be within the range of 0.8 to 3.

The reason for this is that when handwriting vibration is grasped as a superposition of a plurality of vibrations having various frequencies, the characteristic vibration recognized by the human body as a “writing feeling” is vibration in a frequency range of 1 to 2 Hz, according to the present invention. Because the inventors found it empirically.

Therefore, by bringing the average value of the amplitude in the frequency range of 1 to 2 Hz closer to that when writing on paper with a pencil, it is possible to effectively reproduce the feeling of writing on paper with a pencil.

Therefore, it is more preferable to set the lower limit of the average value of the amplitude in the frequency range of 1-2Hz to be 1 or more, and it is more preferable to set it as 1.1 or more.

Moreover, as for the upper limit of the average value of the amplitude in the range of a frequency of 1-2 Hz, it is more preferable to set it as a value of 2 or less, and it is more preferable to set it as a value of 1.6 or less.

In addition, the average value of amplitude means a value obtained by taking the sum of the maximum and minimum values of all amplitudes in the target frequency section and dividing by the number of amplitudes.

Moreover, it is preferable to make the maximum value of the amplitude in the range of a frequency of 1-2 Hz into the value within the range of 2-10.

The reason for this is that when this maximum value is less than 2, the value becomes excessively smaller than the maximum value when writing on paper with a pencil, and it is difficult to effectively reproduce the writing feeling when writing on paper with a pencil. Because there are cases where it can be cancelled. On the other hand, if this maximum value exceeds 10, the value becomes excessively larger than the maximum value when writing on paper with a pencil, and it becomes difficult to effectively reproduce the writing feeling when writing on paper with a pencil. Because there are cases.

Accordingly, the lower limit of the maximum value of the amplitude in the frequency range of 1 to 2 Hz is more preferably 2.5 or more, still more preferably 2.7 or more, and particularly preferably 2.8 or more.

Moreover, it is more preferable to set the upper limit of the maximum value of the amplitude in the frequency range of 1 to 2 Hz to a value of 9 or less, and it is more preferable to set it as a value of 8 or less.

In addition, from the viewpoint of more effectively reproducing the writing feeling when writing on paper with a pencil, it is preferable to have at least one peak with an amplitude of 1.5 or more in a frequency range of 1 to 2 Hz, and it is desirable to set the lower limit of the number of such peaks to two or more values. It is more preferable, and it is still more preferable to set it as four or more values.

Moreover, it is preferable to set the upper limit of the number of such peaks to a value of nine or less, and it is more preferable to set it to a value of eight or less.

(ii) Amplitude in the frequency range of 2 to 5 Hz

Moreover, it is preferable not to have a peak with an amplitude of 5 or more in the frequency range of 2-5 Hz.

The reason for this is that, when a peak with an amplitude of 5 or more in this frequency range is generated, a feeling of pinching of the nib occurs or a large vibration different from a delicate vibration such as a feeling of writing is likely to be felt.

Moreover, it is preferable to make the average value of the amplitude in the range of frequency 2-5 Hz into the value within the range of 0.01-1.5.

The reason for this is that when this average value is less than 0.01, the value becomes excessively smaller than the average value when writing on paper with a pencil, and it becomes difficult to effectively reproduce the writing feeling when writing on paper with a pencil. because there is Moreover, it is because control of the amplitude in the frequency range of 1 to 2 Hz becomes difficult, and it may become difficult to effectively reproduce the writing feeling when writing on paper with a pencil. On the other hand, when this average value exceeds 1.5, it becomes an excessively larger value than the average value when writing on paper with a pencil, making it difficult to effectively reproduce the feeling of writing on paper with a pencil. because there is Moreover, it is because control of the amplitude in the frequency range of 1 to 2 Hz becomes difficult, and it may become difficult to effectively reproduce the writing feeling when writing on paper with a pencil.

Accordingly, the lower limit of the average value of the amplitudes in the frequency range of 2 to 5 Hz is more preferably 0.1 or more, still more preferably 0.2 or more, and particularly preferably 0.3 or more.

In addition, the upper limit of the average value of the amplitudes in the frequency range of 2 to 5 Hz is more preferably set to a value of 1.2 or less, still more preferably set to a value of 0.8 or less, and particularly preferably set to a value of 0.6 or less. .

Moreover, it is preferable to make the maximum value of the amplitude in the frequency range of 2-5 Hz into the value within the range of 0.1-5.

The reason for this is that when this maximum value is less than 0.1, the value becomes excessively smaller than the maximum value when writing on paper with a pencil, and it is difficult to effectively reproduce the feeling of writing on paper with a pencil. Because there are cases where it can be cancelled. Moreover, it is because control of the amplitude in the frequency range of 1 to 2 Hz becomes difficult, and it may become difficult to effectively reproduce the writing feeling when writing on paper with a pencil. On the other hand, when this maximum value exceeds 5, it becomes an excessively larger value than the maximum value when writing on paper with a pencil, and it becomes difficult to effectively reproduce the feeling of writing on paper with a pencil. Because there are cases. Moreover, it is because control of the amplitude in the frequency range of 1 to 2 Hz becomes difficult, and it may become difficult to effectively reproduce the writing feeling when writing on paper with a pencil.

Accordingly, the lower limit of the maximum value of the amplitude in the frequency range of 2 to 5 Hz is more preferably 0.6 or more, still more preferably 0.8 or more, and particularly preferably 1 or more.

Further, the upper limit of the maximum value of the amplitude in the frequency range of 2 to 5 Hz is more preferably set to a value of 4 or less, still more preferably set to a value of 3 or less, and particularly preferably set to a value of 2.4 or less. do.

5. Manufacturing method of writing feeling improvement film

As a method for producing a writing feeling improving film of the present invention, first, a composition for forming a writing feeling improving layer is applied to the surface of a base film by a conventionally known method, for example, a bar coating method, a knife coating method, a roll coating method, or a blade coating method. A coating film is formed by coating using a method, a die coating method, a gravure coating method, or the like.

Next, after drying the coating film, by irradiating an active energy ray to harden the coating film, and making the coating film into a writing feeling improving layer, a writing feeling improvement film is obtained.

Moreover, as hardening of a coating film, it is preferable to irradiate active energy rays, such as an ultraviolet-ray and an electron beam, with respect to a coating film.

Ultraviolet irradiation can be performed by a high-pressure mercury lamp, a fusion H lamp, a xenon lamp, etc. It is preferable to make the irradiation amount into about 50-1000 mW/cm<2> of illumination intensity, and 50-1000 mJ/cm<2> of light intensity.

On the other hand, electron beam irradiation can be performed with an electron beam accelerator etc., It is preferable to make the irradiation amount into about 10-1000 krad.

In addition, by applying the writing feeling improving film of the above-described embodiment to the surface of the touch panel, for example, a display device with a touch panel having excellent writing feeling characteristics as shown in FIG. 4 can be configured.

That is, FIG. 4 is a detailed cross-sectional view showing an example of a display device with a touch panel 25 to which the writing feeling improving film 1 ′ of the present invention is applied. The display device with a touch panel 25 has a structure shown below. have it

In addition, in the display device 25 with a touch panel, the writing feeling improving layer 10 serves as the uppermost surface.

The LCD module 21 comprising the backlight unit 14, the polarizing plate 13, the pressure-sensitive adhesive layer 30c, and the liquid crystal display element (LCD) 12 is disposed on the lower surface of the concave-convex tracking member 11, the liquid crystal display element ( 12) is attached so that it is in contact.

On the other hand, the lower substrate 18 made of the retardation film 2 with the transparent conductive film 9 is affixed to the upper surface of the uneven followable lamination member 11 so that the retardation film 2 is in contact.

Further, the upper substrate 17 made of the retardation film 5 with the transparent conductive film 6 is laminated on the spacer 7 so that the transparent conductive film 6 is in contact with the spacer 7 so that an air gap 8 is formed. .

And the member 16 which consists of the polarizing plate 4 with an adhesive layer 30b is affixed on the retardation film 5 via the adhesive layer 30b.

Moreover, it is the touch panel module 22 that the lower board|substrate 18, the spacer 7 for air gap 8 formation, the upper board|substrate 17, and the member 16 were integrated.

Moreover, the writing feeling improvement film 1' with an adhesive layer which has the adhesive layer 30a on the lower surface is stuck on the polarizing plate 4 in the touch panel module 22 via the adhesive layer 30a. . The writing feeling improving film 1 ′ has the writing feeling improving layer 10 on the upper surface of the base film 20 and the pressure-sensitive adhesive layer 30a on the lower surface.

(Example)

Hereinafter, the present invention will be described in more detail by way of Examples. However, the present invention is not limited to these descriptions.

[Example 1]

1. Preparation of writing feeling improvement film

(1) Preparation of the composition for forming a writing feeling improving layer

As shown below, while mixing active energy ray-curable resin as (A) component, filler as (B) component, leveling agent as (C) component, and photoinitiator as (D) component, propylene glycol It diluted with a mixed solvent of monomethyl ether and isobutanol to prepare a composition for forming a writing feeling improving layer having a solid content concentration of 30% by weight.

In addition, the compounding quantity in the following and Table 1 shows the value converted by the pure part.

(A) component: 100 parts by weight of dipentaerythritol hexaacrylate

(Shin-Nakamura Chemical Co., Ltd., NK Ester A-DPH)

(B) component: 9.5 parts by weight of silica particles

(Prepared by pulverizing silica particles with an average particle diameter of 7 μm with a ball mill, arithmetic mean particle diameter: 1.5 μm, Cv value: 88%, shape: irregular)

(C) component: 0.1 parts by weight of polydimethylsiloxane

(Toray Dow Corning Co., Ltd., SH28)

(D) component: 3 parts by weight of 1-hydroxycyclohexylphenyl ketone

(manufactured by BASF, Irgacure 184)

In addition, the Cv value of (B) component means the coefficient of variation of the particle size distribution represented by following formula (1).

Cv value (%) = (standard deviation particle diameter / arithmetic mean particle diameter) x 100 (1)

In addition, the arithmetic mean particle diameter and Cv value of (B) component were measured using the laser diffraction scattering type particle size distribution analyzer (Horibase Corporation make, LA-920).

At this time, propylene glycol monomethyl ether was used as a dispersing solvent.

(2) Application process

Next, the obtained composition for forming a writing feeling improving layer is applied to an easily adhesive layer of a PET film with an easily adhesive layer as a base film (Toray Co., Ltd., Lumira U48, thickness: 125 μm), and the coating layer has formed

(3) drying process

Next, the obtained application layer was dried on condition of 70 degreeC and 1 minute using the hot air drying apparatus.

(4) curing process

Next, the dried coating layer is irradiated with UV light under the following conditions using an ultraviolet irradiation device (manufactured by GS Yuasa Corporation, light source: high-pressure mercury lamp) to cure the coating layer to improve writing feeling with a thickness of 5 μm It was set as a layer, and the final writing feeling improvement film was obtained.

Lamp power: 1.4kW

Conveyor speed: 1.2m/min

Illuminance: 100mW/cm2

Light quantity: 240mJ/㎠

2. Evaluation

(1) Measurement of nib resistance

The nib resistance in the obtained writing feeling improvement film was measured.

That is, as shown in Fig. 2, the nib of a touch pen (ACK-2003 manufactured by Wacom Co., Ltd., ACK-2003) provided with a hard felt nib having a nib diameter of 0.5 mm is applied to the surface of the writing feeling improving layer. The touch pen was moved in an arbitrary direction parallel to the film surface of the writing feeling improvement film at a speed of 100 mm/min while contacting under a pressure condition of a load of 3.92 N so that the axis of the pen was orthogonal to the film surface of the writing feeling improvement film.

Then, using a detector (manufactured by Shimadzu Corporation, AUTOGRAPH AG-IS 500N), the nib resistance force (mN) according to the movement distance (mm) was measured, and the movement distance (mm) - nib resistance force (mN) got a chart

Further, from the obtained movement distance (mm)-nib resistance (mN) chart, the average value, the maximum value, and the minimum value of the nib sliding resistance were obtained, and the nib sliding coefficient (-) was calculated. The obtained result is shown in Table 1.

In addition, the range of the movement distance when the average value, the maximum value, and the minimum value were calculated|required was made into the range of 50 mm from the point where the influence of the pen tip initial motion resistance converges. That is, the above-mentioned various analyzes were performed using the range of the movement distance of 30-80 mm.

(2) Fourier transform

Next, the obtained moving distance (mm)-nib resistance (mN) chart was subjected to Fourier transform using Excel (registered trademark) to obtain a frequency (Hz)-amplitude (-) chart.

Further, from the obtained frequency (Hz)-amplitude (-) chart, the average value, the maximum value, and the number of peaks having an amplitude equal to or greater than a predetermined amplitude in the ranges of 1 to 2 Hz and 2 to 5 Hz were obtained. The obtained result is shown in Table 1.

(3) Measurement of arithmetic mean roughness Ra

The arithmetic surface roughness Ra in the obtained writing feeling improvement film was measured.

That is, using a contact roughness meter (manufactured by Mitutoyo Co., Ltd., SV3000S4), the arithmetic mean roughness Ra (µm) in the writing feeling improving layer of the obtained writing feeling improving film was measured in accordance with JIS B 0601-1994. . The obtained result is shown in Table 1.

(4) Measurement of haze value

The haze value in the obtained writing feeling improvement film was measured.

That is, the haze value (%) of the obtained writing feeling improvement film was measured based on JISK7136-2000 using the haze meter (Nippon Denshoku Kogyo Co., Ltd. product, NDH2000). The obtained result is shown in Table 1.

(5) Evaluation of writing feeling

(5)-1 Nib slip feeling

The nib slip feeling in the obtained writing feeling improvement film was evaluated.

That is, the obtained writing feeling improving film was fixed on a glass plate so that the writing feeling improving layer might be upward, and it was set as the sample.

Next, the paneler was given a predetermined writing operation on the sample with a touch pen (manufactured by Wacom Co., Ltd., ACK-2003), and evaluated according to the following criteria to evaluate the slip feeling of the nib. The obtained result is shown in Table 1.

◎: The nib does not slip

○ : The pen tip is slightly slippery

× : The pen tip is too slippery

(5)-2 nib jamming feeling

Similarly, according to the following criteria, the nib snagging feeling was evaluated. The obtained result is shown in Table 1.

◎: I do not care about the feeling of the pen tip jamming

○: Slightly stuck feeling of the pen tip remains

× : The pen tip is jammed too much

(5)-3 scratching sound

Similarly, the scratching sound was evaluated according to the following criteria. The obtained result is shown in Table 1.

◎: You can hear a sufficiently crunchy sound.

○: A crackling sound is heard, but slightly low

△ : A slight crackling sound is heard.

×: No crackling sound

(5)-4 vibration

Similarly, vibration was evaluated according to the following criteria. The obtained result is shown in Table 1.

◎ : Appropriate vibration is transmitted to the hand

○: Vibration is transmitted to the hand, but not enough

×: Vibration transmitted to the hand is too small or too large

(6) Evaluation of glare

Generation|occurrence|production of the glare in the obtained writing feeling improvement film was evaluated.

That is, first, a lattice pattern in which light transmitting portions were provided so as to be 200 ppi (pixel/inch) was prepared.

After providing a metal vapor deposition layer on a glass plate, such a grid|lattice pattern was created by resist-processing and etching a metal vapor deposition layer, and also removing a resist.

Next, the prepared grid pattern was placed on a backlight (manufactured by King Co., Ltd., Bright Box 5000).

Next, the obtained writing feeling improving film was placed on the grid pattern so that the writing feeling improving layer was facing up, and the occurrence of glare was confirmed.

Next, when the writing feeling-improving film is moved in a direction parallel to the film plane on a grid pattern, and the location of occurrence of glare confirmed in advance moves together with the writing-feeling improvement film, the occurrence of the glare is transferred to the writing feeling improvement film. It was judged that it was caused and evaluated according to the following criteria. The obtained result is shown in Table 1.

◎ : No glare confirmed

○ : Slight glare is confirmed

×: Glare was remarkably confirmed

[Example 2]

In Example 2, when preparing the composition for forming a writing feeling improving layer, a writing feeling improving film was prepared and evaluated in the same manner as in Example 1 except that the blending amount of silica particles as component (B) was changed to 10 parts by weight. The obtained result is shown in Table 1. In addition, the movement distance (mm)-nib resistance (mN) chart obtained in FIG. 3A is shown, and the frequency (Hz)-amplitude (-) chart obtained in FIG. 3B is shown.

[Example 3]

In Example 3, when preparing the composition for forming a writing feeling improving layer, a writing feeling improving film was prepared and evaluated in the same manner as in Example 1 except that the blending amount of silica particles as component (B) was changed to 12 parts by weight. The obtained result is shown in Table 1.

[Comparative Example 1]

In Comparative Example 1, when the composition for forming a writing feeling improving layer was prepared, as silica particles as component (B), Fuji Shiri Shia Chemical Co., Ltd. Cyclohovic 702 (arithmetic mean particle diameter: 4.1 µm, Cv value: 48%, shape: amorphous) Except having used 8.9 parts by weight, a writing feeling improving film was prepared and evaluated in the same manner as in Example 1. The obtained result is shown in Table 1. In addition, the movement distance (mm) - nib resistance chart obtained in Fig. 5 (a) is shown, and the frequency (Hz) - amplitude (-) chart obtained in Fig. 5 (b) is shown.

[Comparative Example 2]

In Comparative Example 2, 7 parts by weight of PMMA particles (arithmetic mean particle diameter: 3.0 µm, Cv value: 32%, shape: spherical) were used as the resin particles as component (B) when preparing the composition for forming a writing feeling improving layer Other than that, similarly to Example 1, a writing feeling improvement film was produced and evaluated. The obtained result is shown in Table 1.

[Comparative Example 3]

In Comparative Example 3, 1.5 parts by weight of PMMA particles (arithmetic mean particle diameter: 1.5 µm, Cv value: 26%, shape: spherical) were used as the resin particles as component (B) when preparing the composition for forming a writing feeling improving layer Except for that, similarly to Example 1, a film for improving the writing feeling was produced and evaluated. The obtained result is shown in Table 1.

[Comparative Example 4]

In Comparative Example 4, when preparing the composition for forming a writing feeling improving layer, a writing feeling improving film was prepared and evaluated in the same manner as in Comparative Example 3 except that the blending amount of the resin particles as component (B) was changed to 3 parts by weight. The obtained result is shown in Table 1.

[Comparative Example 5]

In Comparative Example 5, when preparing the composition for forming a writing feeling improving layer, a writing feeling improving film was prepared and evaluated in the same manner as in Comparative Example 3 except that the blending amount of the resin particles as component (B) was changed to 8 parts by weight. The obtained result is shown in Table 1.

[Comparative Example 6]

In Comparative Example 6, when preparing the composition for forming a writing feeling improving layer, a writing feeling improving film was prepared and evaluated in the same manner as in Comparative Example 3 except that the blending amount of the resin particles as component (B) was changed to 10 parts by weight. The obtained result is shown in Table 1. In addition, the movement distance (mm)-nib resistance (mN) chart obtained in FIG. 6(a) is shown, and the frequency (Hz)-amplitude (-) chart obtained in FIG. 6(b) is shown.

[Reference Example 1]

In Reference Example 1, paper (manufactured by Kokuyo S&T Co., Ltd., Campus Note A ruled line No-201A) was used instead of the writing feeling improvement film, and a pencil (manufactured by Mitsubishi Pencil Co., Ltd., Uni, hardness: HB) was used instead of the touch pen. ) was evaluated similarly to Example 1 (except for evaluation of arithmetic mean roughness Ra, haze value, and glare). The obtained result is shown in Table 1. In addition, the movement distance (mm)-nib resistance (mN) chart obtained in FIG. 7(a) is shown, and the frequency (Hz)-amplitude (-) chart obtained in FIG. 7(b) is shown.

[Table 1]

As described above, according to the present invention, in the writing feeling improving film including the base film and the writing feeling improving layer, there is provided a composition for forming a writing feeling improving layer for forming the writing feeling improving layer, comprising: an active energy ray-curable resin; By using a composition containing amorphous silica particles having a predetermined arithmetic mean particle diameter and a Cv value, the writing vibration can be stably controlled within a predetermined range, and the writing feeling when writing on paper with a pencil can be effectively reproduced.

Therefore, it is expected that the writing feeling improvement film of the present invention significantly contributes to the improvement of the writing feeling and visibility when inputting using a touch pen to a touch panel.

1: writing feeling improvement film 2: retardation film
4: polarizing plate 5: retardation film
6: transparent conductive film 7: spacer
8: air gap 9: transparent conductive film
10: writing feeling improving layer 11: uneven followable lamination member
12: liquid crystal display element (LCD) 13: polarizing plate
14: backlight unit 16: absence
17: upper substrate 18: lower substrate
20: base film 22: touch panel module
25: display device with touch panel 30: pressure-sensitive adhesive layer
40: glass plate 50: touch pen
52: nib 60: weight
70: measurement only bogie 72: through hole
80: pulley 90: tension string
100: detector

Claims (7)

A writing feeling improving film for a touch panel comprising a base film and a writing feeling improving layer,
The writing feeling improving layer is composed of a cured product of a composition for forming a writing feeling improving layer comprising an active energy ray-curable resin as a component (A) and a filler as a component (B);
The filler as the component (B) contains amorphous silica particles,
Let the compounding quantity of the amorphous silica particle as said (B) component be the value within the range of 5-25 weight part with respect to 100 weight part of active energy ray-curable resins as said (A) component,
Let the arithmetic mean particle diameter of the amorphous silica particles be a value within the range of 0.5 to 3 μm,
Let the Cv value of the amorphous silica particles be within the range of 88 to 200%,
The arithmetic mean roughness Ra in the writing feeling improving layer is set to a value within the range of 0.05 to 0.5 µm, and
With respect to the surface of the writing feeling improving layer, the nib of a touch pen having a hard felt core having a nib diameter of 0.5 mm is pressed under a load of 3.92 N such that the axis of the touch pen is perpendicular to the film surface of the writing feeling improving film. while in contact with the pen, the nib sliding coefficient when the nib resistance is measured by moving the touch pen in any one direction parallel to the film surface of the writing feeling improving film at a speed of 100 mm/min is set to 0.05 to 0.5. A writing feeling improvement film, characterized in that the value is within the range. delete delete delete According to claim 1,
A writing feeling improving film, wherein the haze value is set to a value within the range of 1 to 40%. According to claim 1,
The writing feeling improving film, characterized in that the thickness of the writing feeling improving layer is set to a value within the range of 0.1 to 50 μm. According to claim 1,
The writing feeling improving film, characterized in that the base film is provided with an adhesive layer on the surface opposite to the side on which the writing feeling improving layer is located.

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