KR20180055703A - Film for increasing a feel of writing - Google Patents

Abstract

An objective of the present invention is to provide a film for providing an advanced feeling of writing, capable of effectively reproducing the feeling of the writing when a user writes with a pencil on a paper by stably controlling writing vibration within a predetermined range and capable of effectively preventing dazzling. In order to solve the problems, the film for providing an advanced feeling of writing for a touch panel includes a base film and a writing feeling improving layer to improve the writing felling. The film has a haze value in the range of 10-40% and has an arithmetic average roughness (Ra) in the range of 0.15-1 μm in the writing feeling improving layer. In addition, a touch pen is moved at a speed of 100 mm/min in one direction parallel to a film surface of a writing feeling improving film while a nib of a touch pen having a hard felt lead contacts the film surface of the writing feeling improving film under the pressurizing condition of the load of 3.92 N to allow a central axis of the touch pen to be perpendicular to the film surface of the writing feeling improving film wherein the diameter of the nib is 0.5 mm so that a nib sliding coefficient is between 0.1 and 0.5 when measuring resistance of the nib.

Description

{FILM FOR INCREASING A FEEL OF WRITING}

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

In particular, the present invention relates to a writing feeling improving film which can stably control handwriting vibration to a predetermined range, effectively reproduce a writing feeling when writing with a pencil on paper, and effectively suppress the occurrence of glare.

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

Particularly, in recent years, a pen input type touch panel using a touch pen has started to be widely used as an input means, and its use in a smart phone, an electronic paper, a tablet PC, a pen tablet, an organic device and the like is rapidly expanding.

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

Therefore, in order to improve the writing feel with the touch pen, a film for application to the surface of the touch panel has been studied (see, for example, Patent Documents 1 and 2).

That is, Patent Document 1 discloses an ultraviolet curable resin composition comprising a polyfunctional (meth) acrylate and / or an organic and / or inorganic filler in a plastic film, wherein a leveling agent is not contained, and toluene, , And 1-butanol, and then irradiating ultraviolet rays. The anti-glare hard coat film of the present invention is characterized in that it comprises an ultraviolet curable resin composition comprising at least one member selected from the group consisting of 1-butanol.

Patent Document 2 discloses a protective film having a thickness of 0.1 to 2 mm and laminated on a touch surface of a touch input device provided on a display surface of a display. The surface layer of the protective film as a new touch surface is essentially transparent, A protective film comprising a soft synthetic resin having abrasion resistance is disclosed.

Japanese Unexamined Patent Publication No. 2012-126804 (claims and the like) Japanese Patent Application Laid-Open No. 6-180628 (claims and the like)

However, the anti-glare hard coat films and the like described in Patent Documents 1 and 2 can be improved to some extent with respect to scratch resistance and self-restoration when scratches have occurred, but the vibration generated between the touch pen (Hereinafter sometimes referred to as " handwriting vibration ") is largely different from handwriting vibration when a pencil is handwritten on paper, resulting in a problem that writing feel is insufficient.

Further, there has also been a problem that a feeling of glare on the screen (hereinafter also referred to as " glare ") is likely to occur.

Therefore, the inventors of the present invention have found that the haze value of the writing feeling improving film and the arithmetic average roughness Ra of the writing feeling improving layer in the writing feeling improving film including the base film and the writing feeling improving layer are set within a predetermined range Further, it is found out that these problems can be solved by defining the pentagonal sliding coefficient when the pen tip of a predetermined touch pen is slid on a predetermined condition with respect to the surface of the writing feeling improving layer in a predetermined range , Thereby completing the present invention.

That is, the present invention provides a writing feeling improving film which can effectively reproduce a writing feeling when writing with a pencil on paper by stably controlling the handwriting vibration to a predetermined range, and effectively suppressing the occurrence of glare .

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 haze value is set to a value within the range of 10 to 40%

The arithmetic mean roughness Ra in the writing feeling improving layer is set to a value within a range of 0.15 to 1 mu m,

The nib of a touch pen having a hard felt core having a pen tip diameter of 0.5 mm was brought into contact with the surface of the writing feeling improving layer at a pressing force of 3.92 N so that the axial center of the touch pen was perpendicular to the film surface of the writing feeling improving film ,

Characterized in that the sliding movement of the touch pen in a certain direction parallel to the film surface of the writing feeling improving film is carried out at a speed of 100 mm / min to set the value of the sliding coefficient of the nib when the nib resistance is measured within a range of 0.1 to 0.5. An improvement film is provided, so that the above-mentioned problem can be solved.

That is, in the writing feeling improving film of the present invention, the haze value of the writing feeling improving film and the arithmetic average roughness Ra of the writing feeling improving layer are set in a predetermined range, and the pen tip of the predetermined touch pen And the sliding coefficient of the pentagon when sliding under predetermined conditions is defined as a predetermined range.

This makes it possible to stably control the handwriting vibration, to effectively reproduce the writing feeling when writing with a pencil on paper, and to effectively suppress the occurrence of glare.

In the present invention, the term "nib resistance" refers to the resistance force applied to the nib when the nib 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 value and the minimum value of the pentagon sliding resistance by the load (3.92 N).

In the present invention, the "pen tip sliding resistance" refers to a pen tip resistance when the pen tip starts to move (hereinafter referred to as the "pen tip resistance") in the movement distance (mm) ) Is converged and the pen tip is in a stable sliding state.

Further, in constructing the writing feeling improving film of the present invention, it is preferable that the average value of the resistance of the pentagonal sliding force under the measurement conditions of the above-mentioned nib resistance is within a range of 500 to 1000 mN.

By such a constitution, it is possible to more effectively reproduce the writing feeling when writing with a pencil on paper, and to suppress the occurrence of glare even more effectively.

Further, in constituting the writing feeling improving film of the present invention, it is preferable that the difference between the maximum value and the minimum value of the pentagonal sliding resistance is within a range of 100 to 300 mN.

By such a constitution, it is possible to more effectively reproduce the writing feeling when writing with a pencil on paper, and also to suppress the occurrence of glare more effectively.

Further, in constructing the writing feeling improving film of the present invention, it is preferable that the writing feeling improving layer includes amorphous silica particles as a filler.

By such a constitution, it is possible to more effectively reproduce the writing feeling when writing with a pencil on paper, and also to suppress the occurrence of glare more effectively.

In forming the writing feeling improving film of the present invention, it is preferable that the thickness of the writing feeling improving layer is within a range of 0.1 to 50 mu m.

By such a constitution, it is possible to more effectively reproduce the writing feeling when writing with a pencil on paper, and also to suppress the occurrence of glare more effectively.

In forming the writing feeling improving film of the present invention, it is preferable that a pressure-sensitive adhesive layer is provided on the surface of the base film opposite to the side where the writing feeling improving layer is located.

By such a constitution, it can be easily applied to the surface of the touch panel.

1 (a) and 1 (b) are diagrams for explaining the structure of a writing feeling improving film of the present invention.
Fig. 2 is a view for explaining a method of measuring the nib resistance; Fig.
3 (a) and 3 (b) are graphs showing a movement distance (mm) - a nib resistance resistance (mN) chart and a frequency (Hz) - amplitude (-) chart of the writing feeling improving film of Example 2 To provide drawings.
4 is a view for explaining a display device with a touch panel to which a writing feeling improving film of the present invention is applied.
5 (a) and 5 (b) are graphs showing a moving distance (mm) - a nib resistance resistance (mN) chart and a frequency (Hz) - amplitude (-) chart of the writing feeling improving film of Comparative Example 1 To provide drawings.
6 (a) and 6 (b) are provided to show a chart of the movement distance (mm) - the nib resistance resistance (mN) chart and the frequency (Hz) - amplitude (-) chart when a pencil is written on paper The drawings.

An embodiment of the present invention is a writing feeling improving film (1) for a touch panel comprising a base film (20) and a writing feeling improving layer (10) as shown in Fig. 1 (a)

The haze value is set to a value within the range of 10 to 40%

The arithmetic average roughness Ra of the writing feeling improving layer 10 is set to a value within a range of 0.15 to 1 mu m,

The pen tip 52 of the touch pen 50 having the hard felt core of 0.5 mm in diameter of the pen tip 52 is pressed against the surface of the writing feeling enhancing layer 10 as shown in Fig. Was brought into contact with the film surface of the writing feeling improving film (1) at a pressure of 3.92 N so as to be orthogonal to the film surface of the writing feeling improving film (1)

The touch pen 50 is moved in an arbitrary one direction D parallel to the film surface of the writing feeling improving film 1 at a speed of 100 mm / min to measure the pentagon sliding force when the nib resistance is measured in a range of 0.1 to 0.5 (1). ≪ / RTI >

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1. Writing sensitivity enhancement 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 preferably comprises at least a cured product of a composition for forming a writing feeling improving layer containing at least an active energy ray curable resin and a filler.

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

(1) -1 (A): Active energy ray-curable resin

The kind of the active energy ray-curable resin as the component (A) contained in the composition for forming a writing feeling improving layer is not particularly limited and may be selected from conventionally known ones and may be an energy ray-curable monomer, an oligomer, .

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

The multifunctional (meth) acrylic monomer is preferably a bifunctional or more multifunctional (meth) acrylic monomer having two or more (meth) acryloyl groups in the molecule, and from the viewpoint of better scratch resistance, More preferably at least one functional, and particularly preferably at least five functional. On the other hand, from the viewpoint of suppressing curling of the writing feeling improving film, the polyfunctional (meth) acrylic monomer is preferably 20 or less, more preferably 12 or less, and particularly preferably 9 or less.

The polyfunctional (meth) acrylic monomer is preferably one having a molecular weight of 1000 or less from the viewpoint of compatibility with other components.

Specific examples of the polyfunctional (meth) acrylic monomers include 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) (Meth) acrylate, caprolactone-modified dicyclopentenyl (meth) acrylate, hydroxypivalic acid neopentyl glycol di (meth) acrylate, dicyclopentanyl di (Meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, isocyanurate di (meth) acrylate, (Meth) acrylate, propylene oxide-modified dipentaerythritol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, propylene oxide-modified trimethylolpropane tri (Meth) acrylate, dipentaerythritol hexa (meth) acrylate, caprolactone-modified dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta And the like.

These may be used singly or in combination of two or more kinds.

Examples of the (meth) acrylate-based prepolymer include polyester acrylate-based, epoxyacrylate-based, urethane acrylate-based, polyol acrylate-based and the like.

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

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

The urethane acrylate-based prepolymer can be obtained, for example, by the reaction of a polyether polyol or a polyester polyol with a polyisocyanate.

The polyol acrylate-based prepolymer can be obtained by esterifying a hydroxyl group of a polyether polyol with (meth) acrylic acid.

These prepolymers may be used alone, or two or more of them may be used in combination, or may be used in combination with the above-mentioned polyfunctional (meth) acrylate-based monomer.

(1) -2 (B) Component: filler

(i) Type

The filler as the component (B) contained in the composition for forming a writing feeling improving layer may be inorganic particles or organic particles, but inorganic particles are more preferable from the viewpoint of improving the hardness of the resulting writing feeling improving layer.

Examples of such inorganic particles include particles composed of silica, titania, zirconia, tin oxide, indium oxide, cadmium oxide, antimony oxide and the like.

Among them, it is preferable to use silica particles.

This is because, if silica particles are sufficiently large, the concavity and convexity of the surface of the writing feeling improving layer becomes more complicated because the Cv value is sufficiently large, so that the writing feeling when writing with a pencil on paper can be reproduced more effectively.

In addition, even if the arithmetic average particle size is small, it is easy to obtain the writing sensitivity characteristic, so that the occurrence of glare can be suppressed more effectively.

These may be used singly or in combination of two or more kinds.

(ii)

It is also preferable that the shape of the filler is amorphous.

The reason for this is that, when the indefinite filler is used, not only the Cv value is increased but also the protrusion of the surface of the writing feeling improving layer corresponds to the irregular shape of the filler as compared with the case of using a regular filler such as spherical , It is easy to obtain the writing sensitivity characteristic.

In the present invention, the term " amorphous " means not a regular shape such as a spherical shape or an elliptical shape but a shape having a plurality of irregular corners or faces.

(iii) Arithmetic average particle size

The arithmetic average particle diameter of the filler is preferably set to a value within a range of 0.5 to 3 mu m.

The reason for this is that when the arithmetic average particle diameter is less than 0.5 占 퐉, the surface of the writing feeling improving layer becomes smooth and the sliding coefficient of the nib is low, and it becomes difficult to effectively reproduce the writing feeling when writing with a pencil on paper Because. On the other hand, when the arithmetic average particle size exceeds 3 mu m, the surface of the writing feeling improving layer becomes gentle irregularities and the arithmetic mean roughness Ra becomes small, so that the writing feeling when writing with a pencil is effectively reproduced Not only becomes difficult but also glare may easily occur.

Therefore, the lower limit value of the arithmetic average particle diameter of the filler is more preferably 0.8 mu m or more, and more preferably 1 mu m or more.

The upper limit of the arithmetic mean particle diameter of the filler is more preferably 2.5 탆 or less, and more preferably 2 탆 or less.

(iv) Cv value

The Cv value of the filler is preferably set to a value within a range of 5 to 200%.

The reason for this is that when the Cv value is less than 5%, the concave-convex shape of the surface of the writing feeling improving layer becomes monotonous, and it becomes difficult to obtain a sufficient writing feeling characteristic. On the other hand, when the Cv value exceeds 200%, particles not contributing to the writing feeling increase, and the required amount of particles increases, so that glare may easily occur.

Therefore, the lower limit value of the Cv value of the filler is more preferably 20% or more, more preferably 40% or more, and particularly preferably 60% or more.

The upper limit of the Cv value of the filler is more preferably 150% or less, and more preferably 100% or less.

(v) Amount

The amount of the filler to be blended is preferably in the range of 5 to 30 parts by weight with respect to 100 parts by weight of the active energy ray curable resin as the component (A).

This is because if the blending amount is less than 5 parts by weight, it becomes difficult to form fine irregularities on the surface of the writing feeling improving layer, so that the arithmetic average roughness and haze value become small, This is because it is difficult to effectively reproduce the writing feeling. On the other hand, when the blending amount exceeds 30 parts by weight, the glare easily occurs or the haze value becomes excessively large, and the visibility of the display image on the display may be excessively lowered.

Therefore, the lower limit of the amount of the filler is more preferably 8 parts by weight or more, and more preferably 10 parts by weight or more.

The upper limit of the amount of the filler is more preferably 20 parts by weight or less, and more preferably 15 parts by weight or less.

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

It is also preferable that the composition for forming a writing feeling improving layer contains a leveling agent as the component (C).

This is because the inclusion of the leveling agent effectively suppresses occurrence of line defects or unevenness on the surface of the obtained writing feeling improving layer, and the thickness can be uniformly controlled.

Examples of the leveling agent include a silicon leveling agent, a fluorine leveling agent, an acrylic leveling agent, and a vinyl leveling agent. Among them, from the viewpoint of leveling property and compatibility with other components, A leveling agent and a fluorine leveling agent are preferable.

The leveling agent may be used alone or in combination of two or more.

As the silicon leveling agent, polydimethylsiloxane or modified polydimethylsiloxane is preferable, and polydimethylsiloxane is particularly preferable.

The fluorine-based leveling agent is preferably a compound having a perfluoroalkyl group or fluorinated alkenyl group in the main chain or side chain. As a commercial product, BYK-340 manufactured by Big Chem Japan Co., Ltd., Futanz 650A, Megapack RS-75 manufactured by DIC Corporation, and V-8FM manufactured by Osaka Kikogaku Kogyo Co., Ltd., and the like.

The blending amount of the leveling agent is preferably in the range of 0.001 to 10 parts by weight, more preferably 0.005 to 5 parts by weight, relative to 100 parts by weight of the active energy ray-curable resin as the component (A) And more preferably in the range of 0.01 to 3 parts by weight.

(1) -4 (D) Component: Photopolymerization initiator

It is also preferable that the composition for forming a writing feeling improving layer contains a photopolymerization initiator as the component (D).

Examples of such photopolymerization initiators include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, acetophenone, Phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1- Methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one, 4- (2-hydroxyethoxy) phenyl- 2-propyl) ketone, benzophenone, p-phenylbenzophenone, 4,4'-diethylaminobenzophenone, dichlorobenzophenone, 2-methyl anthraquinone, 2-ethyl anthraquinone, 2-methylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyldimethylketal, acetophenone dimethylketal, p-dimethylamino Benzoic acid esters and the like.

These may be used singly or in combination of two or more kinds.

The blending amount of the photopolymerization initiator is preferably within a range of usually 0.2 to 10 parts by weight based on 100 parts by weight of the active energy ray curable resin as the component (A).

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

Further, the composition for forming a writing feeling improving layer can be prepared by adding the aforementioned components (A) to (D), etc., and dissolving or dispersing them in a suitable solvent, if necessary.

As components other than the components (A) to (D), for example, an antistatic agent, a surfactant, an antioxidant, an ultraviolet absorber, a silane coupling agent, a light stabilizer, and an antifoaming agent may be added.

Examples of the solvent to be used include alcohols such as methanol, ethanol, isopropanol, n-butanol, isobutanol, and octanol; Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; Esters such as ethyl acetate, butyl acetate, ethyl lactate and? -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; And amides such as dimethylformamide, dimethylacetamide and N-methylpyrrolidone.

(2) Thickness

The thickness of the writing feeling improving layer is preferably in the range of 0.1 to 50 mu m.

This is because if the thickness is less than 0.1 탆, it may become difficult to secure sufficient writing sensitivity characteristics. On the other hand, when the thickness exceeds 50 탆, curl tends to occur in the writing feeling improving film.

Therefore, the lower limit value of the thickness of the writing feeling improving layer is more preferably 1 mu m or more, and more preferably 3 mu m or more.

Further, the upper limit value of the thickness of the writing feeling improving layer is more preferably 20 mu m or less, and more preferably 10 mu m or less.

2. Base film

Examples of the base film include, but not limited to, polyester films such as polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate, polyolefin films such as polyethylene film and polypropylene film, A polyvinyl alcohol film, an ethylene-vinyl acetate copolymer film, a polystyrene film, a polycarbonate film, a polymethylpentene film, a polyvinylidene chloride film, a polyvinylidene chloride film, A fluororesin film, a polyamide film, an acrylic resin film, a polyurethane resin film, a norbornene-based polymer film, a cyclic olefin-based polymer film, a cyclic conjugated aromatic ring Diene polymerization Film, a plastic film such as a vinyl alicyclic hydrocarbon polymer film, or a laminated film thereof.

Among them, a polyethylene terephthalate film, a polycarbonate film, a norbornene polymer film and the like are preferable from the viewpoint of mechanical strength and the like.

In addition, in the base film, it is preferable that the surface treatment is performed on one surface or both surfaces by primer treatment, oxidation, irregularity or the like for the purpose of improving adhesion with the layer provided on the surface.

The thickness of the base film is preferably in the range of 15 to 300 mu m, more preferably in the range of 30 to 200 mu m.

3. Adhesive layer

1 (b), it is preferable that the pressure-sensitive adhesive layer 30 is provided on the surface of the base film 20 opposite to the side where the writing feeling improving layer 10 is located.

As the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer, for example, known pressure-sensitive adhesives such as an acrylic pressure-sensitive adhesive, a rubber pressure-sensitive adhesive and a silicone pressure-sensitive adhesive can be used.

4. Characteristics

(1) Arithmetic mean roughness Ra

In the present invention, the arithmetic mean roughness Ra of the writing feeling improving layer of the writing feeling improving film is set to a value within a range of 0.15 to 1 mu m.

The reason is that the arithmetic average roughness Ra is set in this range to stably control the handwriting vibration to a predetermined range in combination with the haze value and the pentagonal sliding coefficient to be described later to effectively reproduce the writing feeling when writing with a pencil on paper This is because the generation of glare can be effectively suppressed.

That is, when the arithmetic average roughness Ra is less than 0.15 占 퐉, there is no protrusion enough to vibrate the pen tip in relation to the human pen pressure. As a result, it becomes difficult to control the handwriting vibration to a predetermined range, and it becomes difficult to effectively reproduce the writing feeling when writing with a pencil on paper. In addition, even when gentle unevenness is formed, the arithmetic mean roughness Ra becomes less than 0.15 mu m. In this case, however, writing sensitivity characteristics are obtained to some degree, but glare occurs. On the other hand, when the arithmetic mean roughness Ra exceeds a value of 1 탆, too large protrusions exist in relation to the human pen pressure. As a result, it becomes difficult to control the handwriting vibration to a predetermined range, which makes it difficult to effectively reproduce a writing feeling when writing with a pencil on paper, or it may become difficult to suppress the occurrence of glare .

Therefore, the lower limit value of the arithmetic mean roughness Ra in the writing feeling improving layer of the writing feeling improving film is more preferably 0.2 mu m or more, and more preferably 0.22 mu m or more.

The upper limit of the arithmetic mean roughness Ra of the writing feeling improving layer of the writing feeling improving film is more preferably 0.4 mu m or less, more preferably 0.3 mu m or less, and more preferably 0.28 mu m or less Is particularly preferable.

(2) Haze value

Further, in the present invention, the haze value of the writing feeling improving film is set to a value within a range of 10 to 40%.

The reason for this is that when the haze value is less than 10%, the protrusion density on the surface of the writing feeling improving layer becomes excessively small. As a result, it becomes difficult to control the handwriting vibration to a predetermined range, and it becomes difficult to reproduce the handwriting feeling when writing with a pencil on paper. On the other hand, when the haze value exceeds 40%, glare may easily occur or the visibility of the display image on the display may be excessively lowered.

Therefore, the lower limit value of the haze value of the writing feeling improving film is more preferably 15% or more, and more preferably 20% or more.

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

Here, the complementary relationship between the arithmetic average roughness Ra and the haze value will be described.

First, the arithmetic average roughness Ra tends to be influenced by the presence of large protrusions. That is, it is possible to grasp whether or not a projection having a height contributing to the writing sensitivity characteristic exists by the arithmetic average roughness Ra.

However, when only the arithmetic mean roughness Ra is used as an index, the magnitude of the protrusion density can not be discriminated, and it becomes difficult to reliably obtain the writing sensitivity characteristic.

On the other hand, the haze value is a numerical value linked with the protrusion density, and the larger the protrusion density, the larger the haze value.

Therefore, by defining the haze value to be equal to or larger than a predetermined value, it is possible to indirectly define the protrusion density that contributes to the writing sensitivity characteristic.

However, when only the haze value is used as the index, the height of the protrusion can not be discriminated, so that it becomes difficult to reliably obtain the writing feeling characteristic.

For the above reason, by specifying both the arithmetic mean roughness Ra and the haze value, it becomes possible to define the height and density of the projections necessary for obtaining excellent writing sensitivity characteristics for the first time.

(3) Writing characteristics

(3) -1 sliding coefficient of the pentagon

2, the writing feeling improving film of the present invention is formed by laminating a hard felt stamper having a pen tip 52 with a diameter of 0.5 mm on the surface of the writing feeling improving layer 10 of the writing feeling improving film 1 The nib 52 of the touch pen 50 provided is brought into contact with the touch pen 50 at a pressing force 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 improving film 1, (50) is moved in an arbitrary one direction parallel to the film surface of the writing feeling improving film (1) at a speed of 100 mm / min to set the value of the pentagon sliding coefficient in the range of 0.1 to 0.5 .

The reason for this is that if the sliding coefficient of the pen tip is less than 0.1, the pen tip tends to slip excessively, and the controllability of the pen tip tends to deteriorate, making it difficult to reproduce a writing feeling when writing with a pencil on paper This is because there are cases. On the other hand, when the sliding coefficient of the pen screw exceeds 0.5, the pen tip is likely to be excessively caught, and conversely, the controllability of the pen tip tends to deteriorate, making it difficult to reproduce a writing feeling when writing with a pencil on paper , And glare may easily occur.

Therefore, it is more preferable to set the lower limit value of the pentagonal sliding coefficient to a value of 0.17 or more, more preferably 0.19 or more.

Further, it is more preferable to set the upper limit value of the pentagonal sliding coefficient to 0.3 or less, more preferably 0.25 or less.

In the present invention, the term "nib resistance" refers to the resistance force applied to the nib when the nib is moved under the above-described conditions.

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

In the present invention, the term " pentagon sliding resistance force " means that the influence of the pen tip initial resistance force when the pen tip starts moving in the movement distance (mm) Means the resistance of the pen tip when it enters the state.

Therefore, for example, in the case of the movement distance (mm) - the nib resistance (mN) chart in the writing feeling improving film of the second embodiment shown in Fig. 3 (a) The pen tip resistance force in the range of the movement distance of 30 mm or more becomes the pentagon sliding resistance force.

The upper limit value of the movement distance when specifying the pen tip sliding resistance is not particularly limited. However, considering the fluctuation of the value due to the frictional heat of the pen tip, etc., .

As described above, the surface shape suitable for the writing sensitivity characteristic can be defined by the arithmetic average roughness Ra and the haze value. However, it is necessary to take into consideration the influence of the surface material and the like on actual writing sensitivity characteristics.

For example, in the case of a material having a high slidability and in a case of a material that is difficult to slip, the writing feeling characteristic largely differs even if the surface shape of the writing feeling improving layer is the same.

This is complemented by the sliding friction coefficient of the pen. The force acting on the pen nib in total can be grasped by the pen sliding coefficient.

As described above, the present invention specifies the writing feeling improving layer from both the surface shape thereof and the characteristic attributed to the material.

Hereinafter, a method of measuring the nib resistance will be described in more detail with an example.

2, the writing sensitivity improving film 1 as a measurement object is fixed to the upper surface of the glass plate 40 such that the writing feeling improving layer 10 is on the upper side.

Next, a measurement dedicated carriage 70 is disposed so as to cross the writing feeling improving film 1, and then, with respect to the through hole 72 extending in the vertical direction provided in the measurement dedicated carriage 70, 50) is inserted.

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

Next, a tensile cord 90 fixed to the measurement dedicated carriage 70 is fixed to the pulley 80 (see FIG. 1) by using a detector 100 such as AUTOGRAPH AG-IS 500N manufactured by Shimadzu Corporation, ), While the film is stretched at a speed of 100 mm / min in a direction D parallel to the film surface, the nib resistance is measured.

Further, by setting the pressure condition higher than the pressure condition in the normal writing of 3.92 N, the pressing force of the pen nib 52 on the writing feeling improving layer 10 becomes stronger. Therefore, the writing feeling improving layer 10 It is possible to react with the concavoconvex shape with higher sensitivity, and furthermore, a slight difference in the concave-convex shape of the writing feeling improving layer 10 can be detected.

(3) -2 Pen tip sliding resistance

For the same reason as that of the above-described nibbling sliding coefficient, it is preferable to set the average value of the nibbing sliding resistance to a value within a range of 500 to 1000 mN.

Therefore, the lower limit value of the average value of the sliding resistance of the pen tip is more preferably 520 mN or more, and more preferably 560 mN or more.

The upper limit value of the average value of the sliding resistance of the pen tip is more preferably 800 mN or less, and more preferably 700 mN or less.

The average value of the pen tip sliding resistance is a value obtained by taking the sum of the maximum value and the minimum value of all the pentagon sliding resistance forces existing in the section in the predetermined moving distance section in which the pen tip sliding resistance is stable and dividing the sum by the number.

It is also preferable that the difference between the maximum value and the minimum value of the pentagonal sliding resistance is within a range of 100 to 300 mN.

The reason for this is that when the value of this difference is less than 100 mN, the handwriting vibration becomes excessively small, and it becomes difficult to reproduce the writing feeling when writing with a pencil on paper. On the other hand, when the value of this difference exceeds 300 mN, the handwriting vibration becomes excessively large, and conversely, it may become difficult to reproduce the writing feeling when writing with a pencil on paper.

Therefore, the lower limit value of the difference between the maximum value and the minimum value of the sliding resistance of the pen tip is more preferably 110 mN or more, and more preferably 120 mN or more.

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

(3) -3 Characteristics of frequency domain

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

3 (b) obtained by Fourier transforming the movement distance (mm) - the nib resistance resistance (mN) chart as shown in Fig. 3 (a) In the frequency (Hz) -amplitude (-) chart as shown in Fig. 4A, it is preferable that the average value of the amplitudes in the range of frequency 1 to 2 Hz is set to a value within the range of 0.8 to 3.

The reason for this is that when the 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 a vibration in the range of 1 to 2 Hz. This is because the inventors have learned it empirically.

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

Therefore, the lower limit value of the average value of the amplitudes in the frequency range of 1 to 2 Hz is more preferably 1 or more, more preferably 1.1 or more.

Further, the upper limit value of the average value of the amplitudes in the frequency range of 1 to 2 Hz is more preferably 2 or less, and more preferably 1.6 or less.

The average value of the amplitudes means a value obtained by taking the sum of the maximum value and the minimum value of all the amplitudes existing in the relevant section in the target frequency section and dividing the sum by the number.

In addition, it is preferable that the maximum value of the amplitude in the frequency range of 1 to 2 Hz is a value within the range of 2 to 10.

The reason for this is that if the maximum value is less than 2, the value becomes excessively smaller than the value of the difference when writing with a pencil on a paper, effectively reproducing the writing feeling when writing with a pencil on paper This is because it may become difficult. On the other hand, when the maximum value exceeds 10, the value becomes excessively larger than the value of the difference when writing with a pencil on paper, and it is difficult to effectively reproduce the writing feeling when writing with a pencil on paper This is because there is a possibility that

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

Further, the upper limit value of the maximum value of the amplitude in the frequency range of 1 to 2 Hz is more preferably 9 or less, more preferably 8 or less.

From the viewpoint of more effectively reproducing the writing feeling when writing with a pencil on paper, it is preferable to have at least one peak having an amplitude of 1.5 or more in a frequency range of 1 to 2 Hz, and it is preferable that the lower limit value of the number of such peaks be two or more More preferably, it is more preferable to set the value to four or more.

Further, the upper limit value of the number of such peaks is desirably set to nine or less, more preferably eight or less.

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

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

This is because if a peak having an amplitude of 5 or more is present in such a frequency range, it is likely to cause a pen tip feeling or a large vibration different from a delicate vibration such as a writing feeling.

Further, it is preferable that the average value of the amplitudes in the frequency range of 2 to 5 Hz is set to a value within the range of 0.01 to 1.5.

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

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

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

Further, it is preferable that the maximum value of the amplitude in the range of the frequency of 2 to 5 Hz is set to a value within the range of 0.1 to 5.

This is because, when the maximum value is less than 0.1, the value becomes excessively smaller than the maximum value when writing with a pencil on paper, and it is difficult to effectively reproduce the writing feeling when writing with a pencil on paper This is because there is a possibility that Moreover, it is difficult to control the amplitude in the range of 1 to 2 Hz in frequency, and it becomes difficult to effectively reproduce the writing feeling when writing with a pencil on paper. On the other hand, when the maximum value exceeds 5, the value becomes excessively larger than the maximum value when writing with a pencil on a paper, and it becomes difficult to effectively reproduce a writing feeling when writing with a pencil on paper This is because there are cases. Moreover, it is difficult to control the amplitude in the range of 1 to 2 Hz in frequency, and it becomes difficult to effectively reproduce the writing feeling when writing with a pencil on paper.

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

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

5. Manufacturing method of writing feeling improving 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 such as a bar coating method, a knife coating method, a roll coating method, Coating method, a gravure coating method, or the like to form a coating film.

Next, after drying the coating film, the coating film is cured by irradiating with an active energy ray to form a writing feeling improving layer, whereby a writing feeling improving film is obtained.

As for curing of the coating film, it is preferable to irradiate the coating film with active energy rays such as ultraviolet rays and electron beams.

The ultraviolet ray irradiation can be performed by a high-pressure mercury lamp, a fusion H lamp, a xenon lamp or the like, and the irradiation amount is preferably about 50 to 1,000 mW / cm 2 and 50 to 1,000 mJ / cm 2.

On the other hand, the electron beam irradiation can be performed by an electron beam accelerator or the like, and the irradiation amount is preferably about 10 to 1000 krad.

Further, by applying the writing feeling improving film of the above-described embodiment to the surface of the touch panel, it is possible to constitute a touch panel-equipped display device having excellent writing feeling characteristics as shown in Fig.

4 is a sectional detailed view showing an example of a touch panel-equipped display device 25 to which the writing feeling improving film 1 'of the present invention is applied. The touch panel attached display device 25 has the following structure I have.

In the display device with a touch panel 25, the writing feeling improving layer 10 is the top surface.

The LCD module 21 composed of the backlight unit 14, the polarizing plate 13, the pressure-sensitive adhesive layer 30c and the liquid crystal display device (LCD) 12 is mounted on the lower surface of the asperity follow- 12 are in contact with each other.

On the other hand, the lower substrate 18 made of the retardation film 2 with the transparent conductive film 9 is adhered to the upper surface of the asperity follower laminating member 11 such that the retardation film 2 comes into contact with the upper substrate.

The upper substrate 17 made of the phase difference 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 the air gap 8 is formed .

The member 16 made of the polarizing plate 4 with the adhesive layer 30b is adhered on the retardation film 5 with the adhesive layer 30b interposed therebetween.

The touch panel module 22 is formed by integrating the lower substrate 18, the spacer 7 for forming the air gap 8, the upper substrate 17, and the member 16.

The writing feeling improving film 1 'with a pressure-sensitive adhesive layer having a pressure-sensitive adhesive layer 30a on the lower surface is adhered to the polarizing plate 4 of the touch panel module 22 via the pressure-sensitive adhesive layer 30a . The writing feeling improving film 1 'has a writing feeling improving layer 10 on the upper surface of the base film 20 and a 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. Manufacture of writing feeling improving film

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

As shown below, the active energy ray curable resin as the component (A), the filler as the component (B), the leveling agent as the component (C), and the photopolymerization initiator as the component (D) And diluted with a mixed solvent of monomethyl ether and isobutanol to prepare a composition for forming a writing feeling improving layer having a solid concentration of 30% by weight.

Incidentally, the blending amounts in the following and Table 1 indicate values converted into pure fractions.

(A) Component: dipentaerythritol hexaacrylate 100 parts by weight

                 (NK Ester A-DPH, manufactured by Shin Nakamura Kagaku Kogyo Co., Ltd.)

Component (B): Silica particles 9.5 parts by weight

         (Silica particles having an average particle diameter of 7 탆 were prepared by grinding with a ball mill, arithmetic average particle diameter: 1.5 탆, Cv value: 88%, shape:

(C) Component: Polydimethylsiloxane 0.1 part by weight

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

(D) Component: 1-hydroxycyclohexyl phenyl ketone 3 parts by weight

          (Irgacure 184, manufactured by BASF Co., Ltd.)

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

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

The arithmetic mean particle diameter and Cv value of the component (B) were measured using a laser diffraction scattering particle size distribution measuring device (manufactured by Horiba Seisakujo Co., Ltd., LA-920).

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

(2) Coating process

Next, the resulting composition for forming a writing feeling improving layer was applied to the adhesive layer of a PET film (Lumirra U48, thickness: 125 占 퐉) made of a PET film (adhesion layer) as a base film, .

(3) Drying process

Next, the obtained coated layer was dried at 70 DEG C for 1 minute using a hot-air drying apparatus.

(4) Curing process

Next, the dried coating layer was irradiated with ultraviolet rays under the following conditions using an ultraviolet irradiator (manufactured by Gisu Yuasa Corporation, light source: high-pressure mercury lamp) to cure the applied layer to improve the writing feeling To obtain a final writing feeling improving film.

Lamp power: 1.4kW

Conveyor speed: 1.2m / min

Illumination: 100 mW / cm 2

Light quantity: 240 mJ / cm 2

2. Evaluation

(1) Measurement of the resistance of the nib

The measurement of the nib resistance of the obtained writing feeling improving film was carried out.

2, a pen tip of a touch pen (ACK-2003, manufactured by Wako Co., Ltd.) having a hard felt core having a pen tip diameter of 0.5 mm was attached to the surface of the writing feeling improving layer, Was moved at a speed of 100 mm / min in an arbitrary direction parallel to the film surface of the writing feeling improving film while being brought into contact with the film surface of the writing feeling improving film at a pressing force of 3.92 N under a pressurizing condition of 3.92 N.

The moving distance (mm) - the nib resistance (mN) was measured by measuring the nib resistance (mN) according to the moving distance (mm) using a detector (AUTOGRAPH AG-IS 500N, manufactured by Shimadzu Corporation) I got a chart.

Further, the average value, the maximum value, and the minimum value of the pentagon sliding resistance force were obtained from the obtained moving distance (mm) - nib resistance (mN) chart, and the pentagon sliding coefficient (-) was calculated. The obtained results are shown in Table 1.

The range of the movement distance when the average value, the maximum value, and the minimum value was obtained was set within a range of 50 mm from the point where the influence of the initial force of the nib resistance converged. That is, the above-described various analyzes were performed using a range of movement distance of 30 to 80 mm.

(2) Fourier transform

Next, a chart of frequency (Hz) -amplitude (-) was obtained by Fourier transforming the obtained moving distance (mm) - nib resistance (mN) chart using Excel (registered trademark).

From the obtained frequency (Hz) -amplitude (-) chart, the average value, the maximum value and the number of peaks whose amplitudes are equal to or larger than a predetermined value were obtained in the frequency range of 1 to 2 Hz and 2 to 5 Hz. The obtained results are shown in Table 1.

(3) Measurement of arithmetic average roughness Ra

The arithmetic surface roughness Ra of the obtained writing feeling improving film was measured.

That is, the arithmetic average roughness Ra (mu m) of the writing sensitivity improving layer of the obtained writing feeling improving film was measured in accordance with JIS B 0601-1994 using a contact type roughing machine (SV3000S4 manufactured by Mitutoyo Co., Ltd.) . The obtained results are shown in Table 1.

(4) Measurement of haze value

The haze value of the obtained writing feeling improving film was measured.

That is, the haze value (%) of the obtained writing feeling improving film was measured using a haze meter (NDH2000, manufactured by Nihon Denshoku Kogyo K.K.) according to JIS K 7136-2000. The obtained results are shown in Table 1.

(5) Evaluation of writing feeling

(5) -1 Nib slip feeling

The feel of the pen tip slip in the obtained writing feeling improving film was evaluated.

That is, the obtained writing feeling improving film was fixed on a glass plate so that the writing feeling improving layer was raised, and a sample was obtained.

Next, a predetermined writing work was simulatively performed on the sample with a touch pen (ACK-2003, manufactured by Wako Co., Ltd.), and evaluated according to the following criteria to evaluate the feel of the pen tip slip. The obtained results are shown in Table 1.

◎: The pen tip does not slip

○: The pen tip slightly slipped

X: The pen tip is too slippery

(5) -2 Pen tip catch

Similarly, according to the following criterion, the feel of the pen tip was evaluated. The obtained results are shown in Table 1.

◎: I do not care about the feeling of the nib

○: There is a little residual feeling of nib

X: too much pen tip

(5) -3 scraping sound

Similarly, according to the following criteria, scratching was evaluated. The obtained results are shown in Table 1.

◎: There is a sound that is sufficiently square.

○: A sound of a square sound is heard, but a little small

△: A sound of a crunchy sound is heard a little.

X: No sound is heard in a square box

(5) -4 vibration

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

◎: Appropriate vibration is transmitted to the hand.

○: Vibration is transmitted to hand but insufficient

X: The vibration transmitted to the hand is too small or too large

(6) Evaluation of glare

The occurrence of glare in the obtained writing feeling improving film was evaluated.

That is, first, a lattice pattern in which a light transmitting portion was provided so as to have a resolution of 200 ppi (pixels / inch) was prepared.

This lattice pattern was prepared by providing a metal deposition layer on a glass plate, then subjecting the metal deposition layer to resist treatment, etching, and further removing the resist.

Next, the prepared lattice pattern was placed on a backlight (Bright Box 5000, manufactured by KING CO., LTD.).

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

Next, when the writing feeling improving film is moved in a direction parallel to the film surface on the lattice pattern and the spot where the glare that has been confirmed in advance is moved together with the writing feeling improving film, the generation of the glare is caused by the writing feeling improving film And evaluated according to the following criteria. The obtained results are shown in Table 1.

◎: No glare confirmed

○: A little glare was confirmed

X: The glare was remarkably confirmed

[Example 2]

In Example 2, a writing feeling improving film was prepared and evaluated in the same manner as in Example 1, except that the amount of the silica particles as the component (B) was changed to 10 parts by weight when the composition for forming a writing feeling improving layer was prepared. The obtained results are shown in Table 1. 3 (a) shows a chart of the moving distance (mm) - the nib resistance force (mN) obtained, and Fig. 3 (b) shows a frequency (Hz) - amplitude (-) chart.

[Example 3]

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

[Comparative Example 1]

In Comparative Example 1, when the composition for forming a writing feeling improving layer was prepared, as the silica particles as the component (B), Cyclo Hobik 702 (arithmetic mean particle diameter: 4.1 탆, Cv value: 48%, shape: amorphous) was used in an amount of 8.9 parts by weight. The obtained results are shown in Table 1. 5 (a) shows the chart of the moving distance (mm) - the nib resistance curve, and Fig. 5 (b) shows the frequency (Hz) - amplitude (-) chart.

[Comparative Example 2]

In Comparative Example 2, 7 parts by weight of PMMA particles (arithmetic average particle diameter: 3.0 탆, Cv value: 32%, shape: spherical) were used as the resin particles as the component (B) when preparing the composition for forming a writing feeling improving layer , A writing feeling improving film was prepared and evaluated. The obtained results are shown in Table 1.

[Comparative Example 3]

In Comparative Example 3, 1.5 parts by weight of PMMA particles (arithmetic average particle diameter: 1.5 mu m, Cv value: 26%, shape: spherical) were used as the resin particles as the component (B) , A writing feeling improving film was produced and evaluated. The obtained results are shown in Table 1.

[Comparative Example 4]

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

[Referential Example 1]

In Reference Example 1, a pencil (made by Mitsubishi Pencil Co., Ltd., Uni, hardness: HB) was used in place of the touch pen by using paper (Kokuyo S & T Co., ) (Except for the evaluation of arithmetic mean roughness Ra, haze value and glare). The obtained results are shown in Table 1. A chart of the moving distance (mm) - the nib resistance resistance (mN) obtained in Fig. 6 (a) is shown and a chart of frequency (Hz) - amplitude (-) obtained in Fig. 6 (b) is shown.

[Table 1]

As described above, according to the present invention, in the writing feeling improving film comprising the base film and the writing feeling improving layer, the haze value of the writing feeling improving film and the arithmetic average roughness Ra of the writing feeling improving layer are defined in a predetermined range Further, by specifying the pentagon sliding coefficient when the pen tip of a predetermined touch pen is slid on the surface of the writing feeling improving layer in a predetermined condition in a predetermined range, the handwriting vibration is stably controlled in a predetermined range, It is possible to effectively reproduce the writing feeling when writing with a pencil and to effectively suppress the occurrence of glare.

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

1: Enhancement of writing feeling Film 2: retardation film
4: polarizer 5: retardation film
6: transparent conductive film 7: spacer
8: Air gap 9: Transparent conductive film
10: writing feeling improving layer 11: concavo-convex follower lamination member
12: liquid crystal display element (LCD) 13: polarizer
14: backlight unit 16: member
17: upper substrate 18: lower substrate
20: base film 22: touch panel module
25: Display device with touch panel 20: Base film
30: pressure-sensitive adhesive layer 40: glass plate
50: touch pen 52: nib
60: Increment 70: Balance for measurement only
72: through hole 80: pulley
90: tensile cord 100: detector

Claims (6)

A writing feeling improving film for a touch panel comprising a base film and a writing feeling improving layer,
The haze value is set to a value within the range of 10 to 40%
The arithmetic mean roughness Ra of the writing sensitivity improving layer is set to a value within a range of 0.15 to 1 mu m,
A pen tip of a touch pen having a hard felt core having a pen tip diameter of 0.5 mm was pressed against the surface of the writing feeling improving layer under a pressing condition of 3.92 N under a load condition of 3.92 N so that the axial center of the touch pen was perpendicular to the film surface of the writing feeling improving film ,
The sliding coefficient of the pen tip when the tip resistance is measured by moving the touch pen at a speed of 100 mm / min in any one direction parallel to the film surface of the writing feeling improving film is set to a value within a range of 0.1 to 0.5 Wherein the writing feeling improving film is made of a thermosetting resin. The method according to claim 1,
Wherein the average value of the resistance value of the pentagonal sliding force under the measurement conditions of the nib resistance is set to a value within a range of 500 to 1000 mN. 3. The method of claim 2,
Wherein a difference between a maximum value and a minimum value of the pentagonal sliding resistance is set to a value within a range of 100 to 300 mN. The method according to claim 1,
Wherein the writing feeling improving layer comprises amorphous silica particles as a filler. The method according to claim 1,
Wherein the writing feeling improving layer has a thickness within a range of 0.1 to 50 占 퐉. The method according to claim 1,
And a pressure-sensitive adhesive layer on the surface of the base film opposite to the side where the writing feeling improving layer is located.

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