Writing-feel-improving sheet

Abstract

A writing-feel-improving sheet 1 with a surface to be touched by a touch pen has an average vibration intensity of 1.2mm / s2 or more in a frequency range of 50-100Hz, the average vibration intensity being acquired from a vibration intensity-period chart obtained by: bringing the pen tip of a specific touch pen into contact with the surface to be touched by a touch pen; then applying a load of 200g to the touch pen and maintaining an angle formed by the touch pen and the surface at 45°; detecting, by an accelerometer, a change in power due to acceleration of vibrations in the same direction as the sliding direction of the touch pen while linearly sliding the touch pen at a speed of 16.6mm / s; and subjecting a power value-time chart, which is obtained between the start of sliding and a sliding distance of 100mm, to fast Fourier transform. The writing-feel-improving sheet 1 offers excellent writing feel with a touch pen.

Description

Writing feel improvement sheet

[0001] The present invention relates to a sheet for improving writing feel.

[0002] In recent years, image display devices (touch panels) with position detection functions that combine display and input functions have become increasingly popular in various electronic devices. In addition to touch panels that allow input with fingers, some also allow input with a touch pen, which allows for more precise and accurate input than with a finger. However, the display module of a touch panel is typically hard. Therefore, the writing experience with a touch pen is not as good as the writing experience with a pencil on paper.

[0003] In order to solve the problem of the writing feel when using a touch pen on a touch panel, it has been considered to attach a film that improves the writing feel (hereinafter, sometimes referred to as a "writing feel improving film" or "writing feel improving sheet") to the outermost surface of the touch panel. For example, Patent Document 1 discloses an example of such a writing feel improving film, which includes a transparent substrate film and linear convex portions that form a mesh structure on at least one surface of the transparent substrate film, the mesh structure having a plurality of regularly arranged compartments, and the linear convex portions occupying 5 to 80% of the area of ​​the entire surface of the touch film.

[0004] JP 2015-054417 A

[0005] However, with the invention disclosed in Patent Document 1, the pen tip had a catching or excessively slippery feel, and the sound and vibrations produced when writing were different from those produced when writing with a pencil on paper, so it was not possible to fully obtain the same writing feel as when writing with a pencil on paper.

[0006] The present invention has been made in view of the above circumstances, and has an object to provide a writing feel improving sheet that provides an excellent writing feel with a touch pen.

[0007] In order to achieve the above object, first, the present invention provides a writing feel improving sheet having a surface that is in contact with a touch pen, wherein after the tip of a predetermined touch pen is brought into contact with the surface that is in contact with the touch pen, a load of 200 g is applied to the touch pen, and the angle formed between the touch pen and the surface is maintained at 45°, and the touch pen is slid linearly at a speed of 16.6 mm / s, while an accelerometer detects changes in power caused by the acceleration of vibration in the same direction as the sliding direction of the touch pen, and a power value-time chart obtained from the start of sliding to a sliding distance of 100 mm is subjected to a fast Fourier transform, and the average value of vibration intensity in a frequency range of 50 to 100 Hz obtained from the obtained vibration intensity-period chart is 1.2 mm / s. ２ A writing feel improving sheet characterized by the above is provided (Invention 1).

[0008] The writing feel improving sheet according to the above invention (Invention 1) has the above physical properties, so that the writing vibration transmitted to the hand when writing with a touch pen is moderate, and a writing feel similar to that of writing with a pencil on paper is obtained. Thus, the writing feel improving sheet is excellent in the writing feel of the touch pen.

[0009] In the above invention (Invention 1), the average value of vibration intensity in the frequency range of 0 to 200 Hz obtained from the vibration intensity-period chart is 10 mm / s ２ It is preferable that the above is true (Invention 2).

[0010] In the above inventions (Inventions 1 and 2), after the tip of a specified touch pen is brought into contact with the surface of the writing feel improvement sheet that the touch pen comes into contact with, a load of 200 g is applied to the touch pen, and the touch pen is slid linearly at a speed of 16.6 mm / s while maintaining the angle between the touch pen and the surface at 45°.The dynamic friction coefficient measured is preferably 0.01 or more and 0.41 or less (Invention 3).

[0011] In the above inventions (Inventions 1 to 3), after the tip of a specified touch pen is brought into contact with the surface of the writing feel improvement sheet that the touch pen comes into contact with, a load of 200 g is applied to the touch pen, and the touch pen is slid linearly at a speed of 16.6 mm / s while maintaining the angle between the touch pen and the surface at 45°.The static friction coefficient measured is preferably 0.01 or more and 0.49 or less (Invention 4).

[0012] In the above inventions (Inventions 1 to 4), it is preferable that the arithmetic mean roughness Ra of the surface of the writing feel improving sheet that comes into contact with the touch pen is 0.2 μm or more and 10 μm or less (Invention 5).

[0013] In the above inventions (Inventions 1 to 5), it is preferable that the ten-point mean roughness Rzjis of the surface of the writing feel improving sheet that comes into contact with the touch pen is 3 μm or more and 10 μm or less (Invention 6).

[0014] In the above inventions (Inventions 1 to 6), it is preferable to provide a base material and a writing feel improving layer that comes into contact with a touch pen (Invention 7).

[0015] In the above invention (Invention 7), the writing feel improving layer is preferably a layer formed by curing a coating composition containing a curable component and a filler (Invention 8).

[0016] The writing feel improving sheet according to the present invention provides an excellent writing feel with a touch pen, and provides a writing feel similar to that of writing with a pencil on paper.

[0017] 1 is a cross-sectional view of a writing feel improving sheet according to one embodiment of the present invention.

[0018] An embodiment of the present invention will be described below. A writing feel improving sheet according to one embodiment of the present invention has a surface that comes into contact with a touch pen, and preferably has the following physical properties. That is, after the tip of a predetermined touch pen is brought into contact with the surface that comes into contact with the touch pen, a load of 200 g is applied to the touch pen, and the angle between the touch pen and the surface is maintained at 45°. The touch pen is slid linearly at a speed of 16.6 mm / s. While the touch pen is slid linearly at a speed of 16.6 mm / s, an accelerometer detects changes in power caused by the acceleration of vibration in the same direction as the sliding direction of the touch pen. A power-time chart obtained from the start of sliding to a sliding distance of 100 mm is subjected to a fast Fourier transform, and the average value of vibration intensity in a frequency range of 50 to 100 Hz obtained from the obtained acceleration (vibration intensity)-period chart is 1.2 mm / s. ２ The above measurement method can be performed by attaching an accelerometer to an existing static / dynamic friction measuring device, and details of the measurement method, including the attachment location, are as shown in the test examples described below. The fast Fourier transform can be performed using an FFT analyzer (manufactured by OROS, product name "OR34J-4").

[0019] In this specification, the power value-time chart obtained by the above measurement method is subjected to a fast Fourier transform, and the acceleration in the resulting acceleration-period chart is referred to as "vibration intensity" (unit: mm / s ２ ) shall be considered.

[0020] The writing feel improving sheet according to this embodiment has the above physical properties, so that the writing vibration transmitted to the hand when writing with a touch pen is moderate, and a writing feel similar to that of writing with a pencil on paper is obtained. In this way, the writing feel improving sheet according to this embodiment is excellent in the writing feel of a touch pen.

[0021] In this embodiment, the vibration intensity in the frequency range of 50 to 100 Hz is specified because, by using the vibration intensity in this frequency range as a standard, a writing feel closest to that of writing with a pencil on paper can be obtained. This was discovered for the first time by the inventors using principal component analysis.

[0022] The writing feel improving sheet according to this embodiment has the above physical properties, and therefore has a suitable unevenness on the surface, and is excellent in anti-glare properties.

[0023] The specified touch pen is not particularly limited, and conventionally known touch pens can be used. For example, touch pens having a polyacetal tip, a hard felt tip, an elastomer tip, or the like can be used. The shape (cross-sectional shape) of the touch pen tip is also not particularly limited, and can be appropriately selected from disk-shaped, circular, polygonal, and the like, but from the viewpoint of ease of obtaining the above physical properties, a circular shape is preferred. When the shape of the touch pen tip is circular, the diameter of the tip is preferably 0.1 to 5 mm, particularly preferably 0.2 to 2 mm, and even more preferably 0.3 to 1 mm.

[0024] From the viewpoint of obtaining an excellent writing feel, the average value of the vibration intensity in the frequency range of 50 to 100 Hz obtained from the vibration intensity-period chart is 1.6 mm / s ２ It is preferable that the speed is 2.0 mm / s or more. ２ More preferably, it is 3.0 mm / s or more. ２ It is preferable that the speed is 4.0 mm / s or more, and more preferably 4.0 mm / s ２ More preferably, it is 5.0 mm / s or more. ２ The upper limit of the average value of the vibration intensity is preferably 50 mm / s or more, from the viewpoint of obtaining an excellent writing feel. ２ Preferably, the speed is 30 mm / s or less. ２ More preferably, it is equal to or less than 15 mm / s ２ It is preferable that the speed is 10 mm / s or less, and more preferably 10 mm / s ２ It is preferable that:

[0025] The average value of vibration intensity in the frequency range of 0 to 200 Hz obtained from the vibration intensity-period chart is 10 mm / s ２ It is preferable that the speed is 15 mm / s or more. ２ More preferably, it is 20 mm / s or more.２ It is preferable that the speed is 25 mm / s or more, and more preferably 25 mm / s ２ More preferably, it is 30 mm / s or more. ２ The upper limit of the average value of the vibration intensity is preferably 100 mm / s or more, from the viewpoint of obtaining an excellent writing feel. ２ Preferably, it is 70 mm / s or less. ２ More preferably, it is equal to or less than 60 mm / s ２ It is preferable that the speed is not more than 50 mm / s. ２ It is preferable that:

[0026] As described above, by using the average value of vibration intensity in the frequency range of 0 to 200 Hz as the reference, it is possible to more effectively obtain a writing feel that is similar to the feel of writing with a pencil on paper.

[0027] Furthermore, from the viewpoint of obtaining an excellent writing feel, the maximum value of vibration intensity in the frequency range of 50 to 100 Hz obtained from the vibration intensity-period chart is set to 6.0 mm / s ２ Preferably, it is 8.0 mm / s or more. ２ More preferably, it is 10 mm / s or more. ２ It is preferable that the speed is 20 mm / s or more, and more preferably 20 mm / s ２ More preferably, it is 30 mm / s or more. ２ The upper limit of the maximum vibration intensity is preferably 100 mm / s or more, from the viewpoint of obtaining an excellent writing feel. ２ Preferably, it is 80 mm / s or less. ２ More preferably, it is equal to or less than 60 mm / s ２ It is preferable that the speed is not more than 50 mm / s. ２ It is preferable that:

[0028] As described above, by using the maximum value of the vibration intensity in the frequency range of 50 to 100 Hz as the reference, it is possible to more effectively obtain a writing feel that is similar to the writing feel when writing with a pencil on paper.

[0029] The minimum value of vibration intensity in the frequency range of 50 to 100 Hz obtained from the vibration intensity-period chart is 0.01 mm / s ２ It is preferable that the speed is 0.02 mm / s or more. ２ More preferably, it is 0.04 mm / s or more, and particularly 0.04 mm / s ２ It is preferable that the speed is 0.05 mm / s or more, and more preferably 0.05 mm / s ２ More preferably, it is 0.07 mm / s or more. ２ The upper limit of the minimum value of the vibration intensity is preferably 10 mm / s or more, from the viewpoint of obtaining an excellent writing feel. ２ Preferably, the speed is 5 mm / s or less. ２ More preferably, it is equal to or less than 1.0 mm / s ２ It is preferable that the speed is 0.50 mm / s or less, and more preferably 0.50 mm / s ２ It is preferable that:

[0030] As described above, by using the minimum value of vibration intensity in the frequency range of 50 to 100 Hz as the standard, it is possible to more effectively obtain a writing feel that is similar to the feel of writing with a pencil on paper.

[0031] The standard deviation of the vibration intensity in the frequency range of 50 to 100 Hz obtained from the vibration intensity-period chart is 1.00 mm / s ２ It is preferable that the speed is 1.50 mm / s or more. ２ More preferably, it is 2.00 mm / s or more, and particularly 2.00 mm / s ２ It is preferable that the speed is equal to or higher than 4.00 mm / s. ２ More preferably, it is 6.00 mm / s or more. ２ The upper limit of the standard deviation of the vibration intensity is preferably 25 mm / s or more, from the viewpoint of obtaining an excellent writing feel. ２ Preferably, the speed is 20 mm / s or less. ２ More preferably, it is equal to or less than 15 mm / s ２ It is preferable that the speed is 10 mm / s or less, and more preferably 10 mm / s ２ It is preferable that:

[0032] As described above, by using the standard deviation of the vibration intensity in the frequency range of 50 to 100 Hz as a reference, it is possible to more effectively obtain a writing feel that is similar to the writing feel when writing with a pencil on paper.

[0033] Furthermore, from the viewpoint of obtaining an excellent writing feel, the maximum value of vibration intensity in the frequency range of 0 to 200 Hz obtained from the vibration intensity-period chart is set to 20 mm / s ２ It is preferable that the speed is 40 mm / s or more. ２ More preferably, it is 60 mm / s or more. ２ It is preferable that the speed is 80 mm / s or more, and more preferably 80 mm / s ２ More preferably, it is 100 mm / s or more. ２ The upper limit of the maximum vibration intensity is preferably 300 mm / s or more, from the viewpoint of obtaining an excellent writing feel. ２ Preferably, the speed is 250 mm / s or less. ２ More preferably, it is equal to or less than 200 mm / s ２ It is preferable that the speed is 160 mm / s or less, and more preferably 160 mm / s ２ It is preferable that the speed is not more than 140 mm / s ２ It is preferable that:

[0034] As described above, by using the maximum value of the vibration intensity in the frequency range of 0 to 200 Hz as the reference, it is possible to more effectively obtain a writing feel that is similar to the writing feel when writing with a pencil on paper.

[0035] The minimum value of vibration intensity in the frequency range of 0 to 200 Hz obtained from the vibration intensity-period chart is 0.01 mm / s ２ It is preferable that the speed is 0.10 mm / s or more. ２ More preferably, it is 1.00 mm / s or more, and particularly 1.00 mm / s ２ It is preferable that the speed is 2.00 mm / s or more, and more preferably 2.00 mm / s ２ More preferably, it is 3.00 mm / s or more. ２ The upper limit of the minimum value of the vibration intensity is preferably 20 mm / s or more, from the viewpoint of obtaining an excellent writing feel. ２Preferably, it is 16 mm / s or less. ２ More preferably, it is equal to or less than 12 mm / s ２ It is preferable that the speed is 8.0 mm / s or less, and more preferably 8.0 mm / s ２ It is preferable that:

[0036] As described above, by using the minimum value of vibration intensity in the frequency range of 0 to 200 Hz as the reference, it is possible to more effectively obtain a writing feel that is similar to the writing feel when writing with a pencil on paper.

[0037] The standard deviation of the vibration intensity in the frequency range of 0 to 200 Hz obtained from the vibration intensity-period chart is 6.00 mm / s ２ It is preferable that the speed is 12 mm / s or more. ２ More preferably, it is 18 mm / s or more. ２ It is preferable that the speed is 24 mm / s or more, and more preferably 24 mm / s ２ More preferably, it is 30 mm / s or more. ２ From the viewpoint of obtaining an excellent writing feel, the upper limit of the standard deviation of the vibration intensity is preferably 80 mm / s or more. ２ Preferably, it is 60 mm / s or less. ２ More preferably, it is equal to or less than 50 mm / s ２ It is preferable that the speed is 45 mm / s or less, and more preferably 45 mm / s ２ It is preferable that:

[0038] As described above, by using the standard deviation of the vibration intensity in the frequency range of 0 to 200 Hz as a reference, it is possible to more effectively obtain a writing feel that is similar to the writing feel when writing with a pencil on paper.

[0039] In the writing feel improving sheet according to this embodiment, the kinetic friction coefficient measured by bringing the tip of a specified touch pen into contact with the surface of the writing feel improving sheet that the touch pen comes into contact with, applying a load of 200 g to the touch pen, and linearly sliding the touch pen at a speed of 16.6 mm / s while maintaining an angle of 45° between the touch pen and the surface, is preferably 0.01 to 0.41, more preferably 0.04 to 0.39, particularly preferably 0.08 to 0.35, even more preferably 0.12 to 0.30, and of these, preferably 0.16 to 0.25. This makes it easier to satisfy the physical properties described above.

[0040] The static friction coefficient obtained by the same measurement method as above is preferably 0.01 to 0.49, more preferably 0.10 to 0.46, particularly preferably 0.16 to 0.42, further preferably 0.22 to 0.38, and of these, preferably 0.28 to 0.34. This makes it easier to satisfy the above-mentioned physical properties.

[0041] The arithmetic mean roughness Ra of the surface of the writing feel improving sheet according to this embodiment that comes into contact with the touch pen is preferably 0.2 to 10 μm, more preferably 0.4 to 5 μm, particularly preferably 0.5 to 2 μm, even more preferably 0.6 to 1.2 μm, and of these, preferably 0.7 to 0.9 μm. This makes it easier to satisfy the above-mentioned physical properties and provides better antiglare properties.

[0042] The ten-point average roughness Rzjis of the surface of the writing feel improving sheet according to this embodiment that comes into contact with the touch pen is preferably 3 to 10 μm, more preferably 3.5 to 9 μm, particularly preferably 4 to 8 μm, even more preferably 4.5 to 7 μm, and of these, preferably 5 to 6 μm. This makes it easier to satisfy the above-mentioned physical properties and provides better antiglare properties.

[0043] The maximum rolling circle height waviness of the surface of the writing feel improving sheet according to this embodiment that comes into contact with the touch pen is preferably 0.1 to 10 μm, more preferably 1 to 7 μm, particularly preferably 2 to 5 μm, even more preferably 2.2 to 4 μm, and of these, preferably 2.4 to 3 μm. This makes it easier to satisfy the above-mentioned physical properties and provides better antiglare properties.

[0044] The details of the methods for measuring the arithmetic mean roughness Ra, the ten-point mean roughness Rzjis, and the maximum rolling circle height waviness in this specification are as described in the test examples below.

[0045] The contact angle of oleic acid (oleic acid contact angle) of the surface of the writing feel improving sheet according to this embodiment that comes into contact with the touch pen is preferably 10° to 120°, more preferably 30° to 100°, particularly preferably 45° to 90°, even more preferably 55° to 80°, and most preferably 60° to 70°. This makes it easier to satisfy the physical properties described above. Note that the oleic acid contact angle in this specification refers to the angle on the side including the droplet, of the angle formed between the tangent to the droplet at the contact portion of the surface and the surface when a droplet of oleic acid is placed on the surface that comes into contact with the touch pen. The same applies to the water contact angle described below.

[0046] The contact angle of the surface of the writing feel improving sheet according to this embodiment that comes into contact with a touch pen with water (water contact angle) is preferably 60° to 120°, more preferably 80° to 110°, particularly preferably 90° to 105°, even more preferably 94° to 102°, and most preferably 97° to 100°. This makes it easier to satisfy the above-mentioned physical properties. Detailed methods for measuring the oleic acid contact angle and water contact angle are as shown in the test examples described below.

[0047] The surface free energy of the surface of the writing feel improving sheet according to this embodiment that comes into contact with the touch pen is 1 to 60 mJ / m ２ is preferably 8 to 50 mJ / m ２More preferably, it is 12 to 40 mJ / m ２ It is preferable that the irradiance is 16 to 30 mJ / m ２ It is preferable that the ２ This makes it easier to satisfy the above-mentioned physical properties. The method for measuring the surface free energy is as shown in the test examples described later.

[0048] The writing feel improving sheet according to this embodiment preferably has the following physical properties: Specifically, data on the sensory evaluation items of writing comfort, pitch, pleasantness of sound, smoothness, softness, slipperiness, vibration, smoothness, and lightness, each rated on a five-point scale (1 to 5), when writing with a standard pencil (standard pencil) (and preferably a reference pencil (reference pencil)) on a standard paper (standard paper); average values ​​of vibration intensity (mm / s) on the writing surface of the standard paper in the frequency ranges of 0 to 50 Hz, 50 to 100 Hz, 0 to 200 Hz, 200 to 400 Hz, 400 to 1000 Hz, and 1000 to 2000 Hz, obtained from the vibration intensity-period chart described above; ２ ), arithmetic mean roughness Ra (μm), ten-point mean roughness Rzjis (μm), rolling circle maximum height waviness (μm); static friction coefficient and dynamic friction coefficient measured by the above-mentioned method using the above-mentioned standard paper and standard pencil (and preferably the reference pencil); data on a five-point scale (1 to 5) of sensory evaluation items, such as writing comfort, pitch, pleasant sound, smoothness, softness, slipperiness, vibration, smoothness, and lightness, when writing on a writing feel improving sheet (the writing feel improving sheet according to this embodiment and preferably other multiple writing feel improving sheets) using a predetermined touch pen; average vibration intensity (mm / s) of the surface of the writing feel improving sheet that comes into contact with the touch pen in each of the frequency ranges of 0 to 50 Hz, 50 to 100 Hz, 0 to 200 Hz, 200 to 400 Hz, 400 to 1000 Hz, and 1000 to 2000 Hz, obtained from the vibration intensity-period chart described above ２), arithmetic mean roughness Ra (μm), ten-point mean roughness Rzjis (μm), rolling circle maximum height waviness (μm); and the static friction coefficient and dynamic friction coefficient measured by the above-mentioned method using the writing feel improvement sheet and touch pen are subjected to principal component analysis to obtain the center of gravity of the reference paper and reference pencil (reference center of gravity) and the center of gravity of the writing feel improvement sheet. In the writing feel improvement sheet according to this embodiment, the distance between the reference center of gravity obtained above and the center of gravity of the writing feel improvement sheet (center-of-gravity distance) is preferably 5.80 or less.

[0049] The reference paper is not particularly limited, and various papers can be selected as the reference paper. In this embodiment, as an example, loose-leaf paper (for example, "Campus (registered trademark) Loose-leaf" by Kokuyo S&T Co., Ltd.) may be selected as the reference paper. The reference pencil is not particularly limited, and for example, pencils such as HB, B, and 2B may be selected as the reference pencil. In this embodiment, as an example, a 2B pencil (for example, "Uni (registered trademark) 2B" by Mitsubishi Pencil Co., Ltd.) may be selected as the reference pencil.

[0050] The sensory evaluation items are evaluated on a five-point scale (1 to 5) as follows, with the writing feel when writing with a reference pencil on reference paper being assigned a rating of "3." The "writing comfort" is evaluated as a value closer to 1 if the writing comfort is perceived to be worse than that of the reference pencil and reference paper, and a value closer to 5 if the writing comfort is perceived to be better than that of the reference pencil and reference paper. The "pitch" is evaluated as a value closer to 1 if the sound is perceived to be lower than that of the reference pencil and reference paper, and a value closer to 5 if the sound is perceived to be higher than that of the reference pencil and reference paper. The "sound pleasantness" is evaluated as a value closer to 1 if the sound is perceived to be less pleasant (more harsh) than that of the reference pencil and reference paper, and a value closer to 5 if the sound is perceived to be more pleasant than that of the reference pencil and reference paper. The "smoothness" is evaluated as a value closer to 1 if the feeling of unevenness is stronger than that of the reference pencil and reference paper, and a value closer to 5 if the feeling of smoothness is stronger than that of the reference pencil and reference paper. The "softness" is evaluated as a value closer to 1 if the feeling of hardness is stronger than that of the reference pencil and reference paper, and a value closer to 5 if the feeling of softness is stronger than that of the reference pencil and reference paper. The closer to 1 the "slipperiness" feels that the pencil has a stronger grip than the reference pencil and paper, and the closer to 5 the closer to 5 the slipperier it feels than the reference pencil and paper. The closer to 1 the "vibration" feels that the pencil has a stronger roughness than the reference pencil and paper, and the closer to 5 the closer to 5 the smoother it feels than the reference pencil and paper. The closer to 1 the "smoothness" feels that the pencil has a stronger firmness than the reference pencil and paper, and the closer to 5 the closer to 5 the smoother it feels than the reference pencil and paper. The closer to 1 the "lightness" feels that the pencil has a heavier writing feel than the reference pencil and paper, and the closer to 5 the closer to 5 the lighter it feels than the reference pencil and paper.

[0051] The writing feel improvement sheet according to this embodiment has the above-mentioned physical property (distance between centers of gravity), and thus provides a writing feel similar to that of writing with a reference pencil on reference paper. For example, if a 2B pencil is selected as the reference pencil and loose-leaf paper is selected as the reference paper, the writing feel improvement sheet according to this embodiment provides a writing feel similar to that of writing with a 2B pencil on loose-leaf paper. This is thought to be because the center of gravity obtained by performing principal component analysis on the above-mentioned data for a given pencil and paper accurately represents the writing feel obtained from those pencils and paper.

[0052] Here, principal component analysis is a statistical analysis method that aggregates data with many variables to create principal components. In this embodiment, data is used to evaluate writing comfort, pitch, pleasantness of sound, smoothness, softness, slipperiness, vibration sensation, smoothness, and lightness on a five-point scale (1 to 5); average vibration intensity (mm / s) in each of the frequency ranges of 0 to 50 Hz, 50 to 100 Hz, 0 to 200 Hz, 200 to 400 Hz, 400 to 1000 Hz, and 1000 to 2000 Hz. ２ ), arithmetic mean roughness Ra (μm), ten-point mean roughness Rzjis (μm), rolling circle maximum height waviness (μm), static friction coefficient, and dynamic friction coefficient data can be aggregated into the first and second principal components, and can be displayed on a two-dimensional graph with the first principal component on the horizontal axis and the second principal component on the vertical axis. Each principal component can be expressed by the following formula. Principal component = k １ x １ +k ２ x ２ +k ３ x ３ +k ４ x ４ +k ５ x ５ +k ６ x ６ +k ７ x ７ +k ８ x ８ +k ９ x ９ +k １０ x １０ +k １１ x １１ +k １２ x １２ +k １３ x １３ +k １４ x １４ +k １５ x １５ +k １６ x １６ +k １７ x １７ +k １８ x １８ +k １９ x １９ +k ２０ x ２０ x １ = Comfortable writing experience １ = x１ Weight (influence) x ２ = Pitch k ２ = x ２ Weight (influence) x ３ = Comfortable sound k ３ = x ３ Weight (influence) x ４ = smooth feeling k ４ = x ４ Weight (influence) x ５ = softness k ５ = x ５ Weight (influence) x ６ = Slipperiness k ６ = x ６ Weight (influence) x ７ = Vibration feeling k ７ = x ７ Weight (influence) x ８ = Smoothness k ８ = x ８ Weight (influence) x ９ = Lightness k ９ = x ９ Weight (influence) x １０ = Average value of vibration intensity at frequencies from 0 to 50 Hz k １０ = x １０ Weight (influence) x １１ = Average value of vibration intensity at frequencies between 50 and 100 Hz k １１ = x １１ Weight (influence) x １２ = Average value of vibration intensity at frequencies from 0 to 200 Hz k １２ = x １２ Weight (influence) x １３ = Average value of vibration intensity at frequencies between 200 and 400 Hz k １３ = x １３ Weight (influence) x １４ = Average value of vibration intensity at frequencies between 400 and 1000 Hz k １４ = x １４ Weight (influence) x １５ = Average value of vibration intensity at frequencies between 1000 and 2000 Hz k １５ = x １５ Weight (influence) x １６= arithmetic mean roughness Ra k １６ = x １６ Weight (influence) x １７ = Ten-point average roughness Rzjis k １７ = x １７ Weight (influence) x １８ = Maximum rolling circle height waviness k １８ = x １８ Weight (influence) x １９ = coefficient of static friction k １９ = x １９ Weight (influence) x ２０ = Coefficient of dynamic friction k ２０ = x ２０ The weight (degree of influence) of each data item is automatically calculated based on the principles of principal component analysis when principal component analysis is performed.

[0053] When performing the principal component analysis, it is preferable to perform preprocessing. Specifically, scaling (standardization) is performed by subtracting the average value from each data value and then dividing by the standard deviation. It is preferable to perform principal component analysis using the scaled data. This allows the distance between the center of gravity of the reference and the center of gravity of the writing feel improvement sheet to be expressed as an absolute value.

[0054] From the above viewpoint, the distance between the centers of gravity is more preferably 5.50 or less, more preferably 5.20 or less, particularly preferably 4.60 or less, even more preferably 4.00 or less, and of these, preferably 3.50 or less. The lower limit of the distance between the centers of gravity is most preferably 0, but is substantially preferably 0.10 or more, more preferably 0.40 or more, particularly preferably 0.80 or more, even more preferably 1.00 or more, and of these, preferably 1.20 or more.

[0055] The haze value of the writing feel improving sheet according to this embodiment is preferably 0 to 50%, more preferably 4 to 40%, particularly preferably 10 to 36%, even more preferably 16 to 32%, and most preferably 22 to 28%. This makes it easier to satisfy the physical properties described above and provides better antiglare properties. It is also suitable for optical applications. The haze value in this specification is a value measured in accordance with JIS K7136:2000.

[0056] The writing feel improving sheet according to this embodiment preferably includes a substrate and a writing feel improving layer that comes into contact with a touch pen. Specifically, as shown in Fig. 1, the writing feel improving sheet 1 according to this embodiment preferably includes a substrate 11 and a writing feel improving layer 12 provided on one side of the substrate 11.

[0057] 1. Elements 1-1. Substrate The substrate 11 may be appropriately selected from those suitable for touch panels in which a touch pen is used, and is preferably a plastic film that has good affinity with the writing feel improving layer 12. However, the substrate 11 may also be a glass plate or glass film.

[0058] Examples of such plastic films include polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, polyolefin films such as polyethylene and polypropylene, cellophane, diacetyl cellulose film, triacetyl cellulose film, acetyl cellulose butyrate film, polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene-vinyl acetate copolymer film, polystyrene film, polycarbonate film, polymethylpentene film, polysulfone film, polyether ether ketone film, polyether sulfone film, polyetherimide film, fluororesin film, polyamide film, acrylic resin film, polyurethane resin film, norbornene polymer film, cyclic olefin polymer film, cyclic conjugated diene polymer film, and vinyl alicyclic hydrocarbon polymer film, or laminate films thereof. Among these, polyethylene terephthalate film, polycarbonate film, and norbornene polymer film are preferred, as they can maintain the writing feel of the touch pen well in combination with the writing feel improving layer 12 described above, and polyethylene terephthalate film is particularly preferred. From the perspective of the SDGs, the material that constitutes the plastic film may be a material with a high biomass content, a material that can be recycled or reused, or a recycled or reused material.

[0059] Furthermore, in order to improve adhesion to layers (such as the writing feel improving layer 12 and the adhesive layer described below) provided on the surface of the substrate 11, one or both sides may be subjected to a surface treatment such as a primer treatment, an oxidation method, or a roughening method, as desired. Examples of oxidation methods include corona discharge treatment, chromic acid treatment, flame treatment, hot air treatment, and ozone / ultraviolet treatment, while examples of roughening methods include sandblasting and solvent treatment. These surface treatment methods are appropriately selected depending on the type of substrate 11. As an example, a plastic film, particularly a polyethylene terephthalate film, on which an easy-adhesion layer has been formed by a primer treatment is preferably used.

[0060] The thickness of the substrate 11 is not particularly limited, but considering the use in a touch panel, it is preferably 25 to 500 μm, more preferably 38 to 400 μm, and even more preferably 50 to 300 μm.

[0061] 1-2. Writing Experience Improving Layer (1) Material of Writing Experience Improving Layer The writing experience improving layer 12 of the writing experience improving sheet 1 in this embodiment may be formed from any material as long as it satisfies the above-described physical property (distance between centers of gravity), but is preferably formed by curing the coating composition C described below. From the perspective of the SDGs, the material constituting the writing experience improving layer 12 may be a material with a high biomass content, a material that can be recycled or reused, or a recycled or reused material.

[0062] The coating composition C in this embodiment preferably contains a curable component and a filler, and further preferably contains a slip agent and a leveling agent, which makes it easier to form the writing feel improving layer 12 that satisfies the above-mentioned physical properties.

[0063] (1-1) Curable Component The curable component is a component that is cured by a trigger such as active energy rays or heat, and examples thereof include an active energy ray-curable component, a thermosetting component, etc. In the present embodiment, it is preferable to use an active energy ray-curable component from the viewpoints of the hardness of the writing feel improving layer 12 to be formed, the heat resistance of the substrate 11 (plastic film), etc.

[0064] Specific examples of the active energy ray-curable component include polyfunctional (meth)acrylate monomers, (meth)acrylate prepolymers, and active energy ray-curable polymers. Among these, polyfunctional (meth)acrylate monomers or (meth)acrylate prepolymers are more preferred. The polyfunctional (meth)acrylate monomers and (meth)acrylate prepolymers may be used alone or in combination. In this specification, the term "(meth)acrylate" refers to both acrylate and methacrylate. The same applies to other similar terms.

[0065] Examples of polyfunctional (meth)acrylate monomers include 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, caprolactone-modified dicyclopentenyl di(meth)acrylate, ethylene oxide-modified phosphate di(meth)acrylate, allylated cyclohexyl di(meth)acrylate, isocyanurate di(meth)acrylate, and trimethylolpropane tri(meth)acrylate. Examples of the polyfunctional (meth)acrylate include polyfunctional (meth)acrylates such as acrylate, dipentaerythritol tri(meth)acrylate, 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, ethylene oxide-modified dipentaerythritol hexa(meth)acrylate, and caprolactone-modified dipentaerythritol hexa(meth)acrylate. These may be used alone or in combination of two or more.

[0066] Examples of the (meth)acrylate prepolymer include polyester acrylate, epoxy acrylate, urethane acrylate, and polyol acrylate prepolymers.

[0067] The polyester acrylate prepolymer can be obtained, for example, by esterifying the hydroxyl groups of a polyester oligomer having hydroxyl groups at both ends, which is obtained by condensation of a polycarboxylic acid and a polyhydric alcohol, with (meth)acrylic acid, or by esterifying the terminal hydroxyl groups of an oligomer obtained by adding an alkylene oxide to a polycarboxylic acid, with (meth)acrylic acid.

[0068] Epoxy acrylate prepolymers can be obtained, for example, by reacting (meth)acrylic acid with the oxirane ring of a relatively low molecular weight bisphenol epoxy resin or novolac epoxy resin to esterify it.

[0069] The urethane acrylate prepolymer can be obtained, for example, by esterifying a polyurethane oligomer obtained by reacting a polyether polyol or polyester polyol with a polyisocyanate with (meth)acrylic acid.

[0070] The polyol acrylate prepolymer can be obtained, for example, by esterifying the hydroxyl groups of a polyether polyol with (meth)acrylic acid.

[0071] The above prepolymers may be used singly or in combination of two or more.

[0072] (1-2) Filler The coating composition C preferably contains a filler, which makes it easier to satisfy the above-mentioned physical properties.

[0073] Examples of fillers include inorganic fine particles such as silica, calcium carbonate, aluminum hydroxide, magnesium hydroxide, clay, talc, and titanium dioxide; organic fine particles such as acrylic resin, polystyrene resin, polyethylene resin, and epoxy resin; and fine particles made of silicon-containing compounds having an intermediate structure between inorganic and organic (for example, the Tospearl series, which are silicone resin fine particles manufactured by Momentive Performance Materials Japan, Inc.). These fillers may be used alone or in combination of two or more.

[0074] The shape of the filler may be regular, such as spherical, or may be irregular, with no particular shape specified. However, from the viewpoint of making it easier to satisfy the above-mentioned physical properties, a regular shape is preferred, and a spherical shape is particularly preferred.

[0075] As a specific filler, it is preferable to use regular-shaped fine particles (e.g., silicone resin fine particles) made of a silicon-containing compound having an intermediate structure between inorganic and organic, and it is particularly preferable to use spherical silicone resin fine particles, which makes it easier to satisfy the above-mentioned physical properties and provides better antiglare properties.

[0076] The refractive index of the filler is preferably 1.2 to 3, more preferably 1.3 to 2, particularly preferably 1.35 to 1.6, and even more preferably 1.4 to 1.5, which makes it easier to achieve the desired optical properties.

[0077] The average particle size of the filler is preferably 0.1 to 20 μm, more preferably 0.5 to 18 μm, particularly preferably 1 to 16 μm, even more preferably 5 to 14 μm, and most preferably 8 to 12 μm. This makes it easier to satisfy the above-mentioned physical properties and provides better antiglare properties. The average particle size of the filler is measured by a centrifugal sedimentation light transmission method.

[0078] The content of the filler in coating composition C (excluding the content of silica nanoparticles, which will be described later) is preferably 1 to 50 parts by mass, more preferably 3 to 40 parts by mass, particularly preferably 4 to 30 parts by mass, even more preferably 5 to 20 parts by mass, and of these, preferably 6 to 10 parts by mass, relative to 100 parts by mass of the curable component. This makes it easier to satisfy the above-mentioned physical properties and provides better antiglare properties.

[0079] In this embodiment, it is also preferable to use silica nanoparticles in combination with the filler. This makes it easier to satisfy the above-mentioned physical properties and provides better anti-glare properties. The average particle size of the silica nanoparticles is preferably 1 to 200 nm, more preferably 5 to 100 nm, and even more preferably 10 to 50 nm. The average particle size of the silica nanoparticles is measured by dynamic light scattering.

[0080] The silica nanoparticles may be modified with an organic substance to improve dispersibility. The silica nanoparticles are also preferably in the form of an organosol (colloidal). The organosol improves the dispersibility of the silica nanoparticles, improving the uniformity and light transmittance of the resulting writing feel improving layer 12.

[0081] The modification with an organic substance can be carried out by a conventional method. For example, CH ２ =C(CH ３ ) COO(CH ２ ) ３ Si(OCH ３ ) ３ The surface of the silica particles can be modified by adding a silane coupling agent having the above structure to an organosol of silica nanoparticles, heating the mixture to about 50° C., and stirring for several hours. The structure and amount of the silane coupling agent to be used are appropriately selected depending on the required degree of dispersibility of the silica nanoparticles.

[0082] As the dispersion solvent for the organosol, methyl ethyl ketone, methyl isobutyl ketone, etc., which have excellent compatibility with the polyfunctional (meth)acrylate and the leveling agent and excellent volatility when the writing feel improving layer 12 is formed, are preferred.

[0083] As the silica nanoparticles, commercially available products can be used, and among them, organosilica sol MEK-ST, MIBK-ST, etc. manufactured by Nissan Chemical Industries, Ltd. are preferably used.

[0084] When coating composition C contains silica nanoparticles, the content thereof is preferably 1 to 50 parts by mass, more preferably 4 to 40 parts by mass, particularly preferably 8 to 30 parts by mass, even more preferably 12 to 25 parts by mass, and of these, preferably 16 to 22 parts by mass, relative to 100 parts by mass of the active energy ray-curable component. This makes it easier to satisfy the above-mentioned physical properties and provides better antiglare properties.

[0085] (1-3) Photopolymerization Initiator When ultraviolet light is used to cure the active energy ray-curable component, it is preferable that the coating composition C contains a photopolymerization initiator. This allows the active energy ray-curable component to be polymerized efficiently, and also reduces the polymerization and curing time and the ultraviolet light irradiation dose.

[0086] Examples of such photopolymerization initiators include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylaminoacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propan-1-one, 4-(2-hydroxyethoxy)phenyl-2-(hydroxy-2-propyl)ketone, benzophenone, Examples of suitable benzoxanthone include 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, oligo[2-hydroxy-2-methyl-1[4-(1-methylvinyl)phenyl]propanone], 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, etc. These may be used alone or in combination of two or more.

[0087] When the coating composition C contains a photopolymerization initiator, the content thereof is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 15 parts by mass, and even more preferably 1 to 10 parts by mass, relative to 100 parts by mass of the active energy ray-curable component, which makes it easier for the resulting writing feel improving layer 12 to have the desired hardness.

[0088] (1-4) Slipping Agent The coating composition C according to this embodiment preferably contains a slipping agent, which makes it easier to satisfy the above-mentioned physical properties.

[0089] Examples of slip agents include silicone-based slip agents, fluorine-based slip agents, and acrylic-based slip agents. Among these, fluorine-based slip agents are preferred because they make it easier to satisfy the above-mentioned physical properties. As the fluorine-based slip agent, a fluorine-based resin having a (meth)acrylate group polymerizable with the polyfunctional (meth)acrylate monomer or (meth)acrylate prepolymer as the curable component is preferred.

[0090] When coating composition C contains a slip agent, the content thereof is preferably 0.01 to 30 parts by mass, more preferably 0.05 to 20 parts by mass, particularly preferably 0.1 to 10 parts by mass, further preferably 0.5 to 5 parts by mass, and most preferably 1 to 2 parts by mass, per 100 parts by mass of the curable component. This makes it easier to satisfy the above-mentioned physical properties.

[0091] (1-5) Leveling Agent The coating composition C according to this embodiment preferably contains a leveling agent, which makes it easier to achieve the above-mentioned physical properties.

[0092] Examples of leveling agents include silicone-based leveling agents, fluorine-based leveling agents, acrylic-based leveling agents, and vinyl-based leveling agents. Among these, silicone-based leveling agents are preferred because they make it easier to satisfy the above-mentioned physical properties. The leveling agents may be used alone or in combination of two or more.

[0093] The leveling agent may be modified or unmodified. Furthermore, the leveling agent may have a reactive group or may not have a reactive group. Among them, modified silicone is preferred, and polyether-modified silicone is particularly preferred.

[0094] When coating composition C contains a leveling agent, the content thereof is preferably 0.01 to 5.0 parts by mass, more preferably 0.1 to 3.0 parts by mass, particularly preferably 0.2 to 1.0 part by mass, and even more preferably 0.3 to 0.6 part by mass, relative to 100 parts by mass of the curable component. This makes it easier to satisfy the above-mentioned physical properties.

[0095] (1-6) Other Components In addition to the above components, the coating composition C of the present embodiment may contain various additives. Examples of the various additives include dispersants, ultraviolet absorbers, infrared absorbers, antioxidants, light stabilizers, antistatic agents, silane coupling agents, antiaging agents, thermal polymerization inhibitors, colorants, refractive index modifiers, surfactants, storage stabilizers, plasticizers, lubricants, and antifoaming agents.

[0096] (2) Thickness The thickness of the writing feel improving layer 12 is preferably 0.5 to 50 μm, more preferably 1.0 to 30 μm, particularly preferably 1.5 to 20 μm, further preferably 2.0 to 10 μm, among which 3.0 to 7.0 μm is preferable, and 3.5 to 5.0 μm is most preferable. This makes it easier to satisfy the above-mentioned physical properties.

[0097] When the thickness of the writing feel improving layer 12 is α (μm) and the average particle size of the filler is β (μm), the value of β / α preferably satisfies 0.001 to 100, more preferably satisfies 0.01 to 50, particularly preferably satisfies 0.1 to 20, even more preferably satisfies 0.5 to 10, more preferably satisfies 1 to 6, and most preferably satisfies 2 to 4. This makes it easier to satisfy the above-mentioned physical properties.

[0098] 1-3. Other Configurations The writing feel improving sheet 1 according to this embodiment may include an adhesive layer on the surface of the substrate 11 opposite the writing feel improving layer 12. The adhesive that constitutes the adhesive layer is not particularly limited, and known adhesives such as acrylic adhesives, rubber adhesives, and silicone adhesives can be used, and it is preferable to use an adhesive having a predetermined transparency.

[0099] When the writing feel improving sheet 1 according to the present embodiment includes the above-described adhesive layer, the writing feel improving sheet 1 according to the present embodiment may have a release film laminated on the surface of the adhesive layer opposite to the substrate 11. The release film is not particularly limited as long as it has the desired releasability on its release surface (the surface in contact with the adhesive layer), and any known release film, such as a resin film having one surface subjected to a release treatment with a release agent, can be used.

[0100] 2. Manufacturing Method of Writing Feel Improving Sheet The writing feel improving sheet 1 according to this embodiment can be manufactured by applying a coating liquid containing a coating composition for the writing feel improving layer 12, preferably coating composition C, and optionally a solvent, to the substrate 11 and curing it to form the writing feel improving layer 12.

[0101] The solvent can be used to improve coatability, adjust viscosity, adjust solid content concentration, etc., and any solvent can be used without particular limitation as long as it dissolves or disperses each component. Specific examples of the solvent include alcohols such as methanol, ethanol, isopropanol, butanol, and octanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; esters such as ethyl acetate, butyl acetate, ethyl lactate, and γ-butyrolactone; ethers such as ethylene glycol monomethyl ether (methyl cellosolve), ethylene glycol monoethyl ether (ethyl cellosolve), diethylene glycol monobutyl ether (butyl cellosolve), and propylene glycol monomethyl ether; aromatic hydrocarbons such as benzene, toluene, and xylene; and amides such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone.

[0102] The coating composition may be applied by a conventional method, such as bar coating, knife coating, roll coating, blade coating, die coating, or gravure coating. After the coating composition is applied, the resulting film is preferably dried at 40 to 120°C for about 30 seconds to 5 minutes.

[0103] When the coating composition is active energy ray curable, such as coating composition C, the coating composition is cured by irradiating the coating film of the coating composition with active energy rays such as ultraviolet rays or electron beams. The ultraviolet irradiation can be carried out using a high-pressure mercury lamp, a Heraeus H lamp, a xenon lamp, or the like. The irradiation dose of ultraviolet rays has an illuminance of 50 to 1000 mW / cm. ２ , light intensity 50-1000mJ / cm ２ On the other hand, electron beam irradiation can be carried out using an electron beam accelerator or the like, and the dose of electron beam irradiation is preferably about 10 to 1000 krad.

[0104] The coating film of the coating composition can be irradiated with active energy rays in an air atmosphere or an inert gas atmosphere. Depending on the type of active energy ray-curable component, the coating composition can be cured well without being inhibited by oxygen by irradiating with active energy rays in an inert gas atmosphere.

[0105] Examples of inert gases include nitrogen, argon, and helium, with nitrogen and argon being preferred, and nitrogen being particularly preferred. The oxygen concentration in the inert gas atmosphere is preferably 5% or less, more preferably 3% or less, and particularly preferably 2% or less.

[0106] 3. Use of the Writing Experience Improving Sheet The writing experience improving sheet 1 according to this embodiment can be used as a sheet constituting the outermost layer of a touch panel (image display device with position detection function) in which a touch pen is used. Specifically, it is preferably used by being laminated on a cover material in a touch panel having a display module such as a liquid crystal (LCD) module, a light-emitting diode (LED) module, or an organic electroluminescence (organic EL) module, or a touch sensor. The writing experience improving sheet 1 is preferably laminated on the cover material by being attached via the aforementioned adhesive layer.

[0107] 4. Touch Panel with Writing Experience Improvement Sheet By laminating the writing experience improvement sheet according to the embodiment described above on a touch panel, a touch panel with a writing experience improvement sheet (including the concept of a display body with a touch panel component) can be obtained. Specifically, the touch panel with writing experience improvement sheet comprises a writing experience improvement sheet having a touch pen contact surface that comes into contact with a touch pen, and a touch panel, with the side of the writing experience improvement sheet opposite the touch pen contact surface laminated on the display surface side of the touch panel. The writing experience improvement sheet may be laminated directly on the display surface of the touch panel, or may be laminated on the display surface side of the touch panel via another member or layer.

[0108] The type and type of the touch panel are not particularly limited, and for example, capacitive, electromagnetic induction, resistive, surface acoustic wave (ultrasonic), infrared, and other touch panels can be used. Among these, capacitive touch panels are preferred from the viewpoint of easily reproducing an excellent writing feel, and capacitive touch panels that also incorporate electromagnetic induction are particularly preferred when taking into account the reproducibility of characters and the like written with a touch pen. The specific configurations of the capacitive and electromagnetic induction touch panels are not particularly limited, and conventionally known touch panels can be used.

[0109] The above-described embodiments have been described to facilitate understanding of the present invention, and are not intended to limit the present invention. Therefore, each element disclosed in the above embodiments is intended to include all design modifications and equivalents that fall within the technical scope of the present invention.

[0110] For example, another layer may be interposed between the substrate 11 and the writing feel improving layer 12 in the writing feel improving sheet 1. In addition, another layer, such as a hard coat layer, may be provided on the surface of the substrate 11 opposite the writing feel improving layer 12.

[0111] In this specification, when it is stated that "X to Y" (X and Y are any numbers), it means "X or more and Y or less" unless otherwise specified, and also means "preferably greater than X" or "preferably smaller than Y". Furthermore, when it is stated that "X or more" (X is any number), it means "preferably greater than X" unless otherwise specified, and when it is stated that "Y or less" (Y is any number), it also means "preferably smaller than Y" unless otherwise specified.

[0112] The present invention will be explained in more detail below with reference to examples, but the scope of the present invention is not limited to these examples.

[0113] Example 1 100 parts by mass of a polyfunctional urethane acrylate (A1; manufactured by Arakawa Chemical Industries, Ltd., product name "Beamset 575CB", product containing a photopolymerization initiator) as an active energy ray-curable component (urethane acrylate-based prepolymer), and 7.2 parts by mass (expressed as a solid content equivalent value) of fine particles (B1; manufactured by Momentive Performance Materials Japan, Inc., product name "Tospearl 1100", average particle size: 11.0 μm, refractive index: 1.43) made of a silicone resin (a silicon-containing compound having an intermediate structure between inorganic and organic) as a filler. The same applies to the other components.) 20.0 parts by mass of organosilica sol (B2; manufactured by Nissan Chemical Industries, Ltd., product name "MIBK-ST", average particle size 10 nm) as silica nanoparticles, 1.2 parts by mass of fluorine-based resin (manufactured by DIC Corporation, product name "Megafac RS-90") as a slip agent, and 0.4 parts by mass of polyether-modified silicone (E1; manufactured by Dow-Toray Industries, Inc., product name "SH28") as a silicone-based leveling agent were mixed in propylene glycol monomethyl ether to obtain a coating liquid of a coating composition.

[0114] The coating liquid of the coating composition obtained above was applied to the surface of the easy-adhesion layer side of a polyester film with an easy-adhesion layer (manufactured by Toray Industries, Inc., product name "Lumirror U40", thickness: 125 μm) as a substrate, and dried at 70° C. for 1 minute.

[0115] Next, under a nitrogen atmosphere, ultraviolet light was irradiated using an ultraviolet irradiation device (manufactured by iGraphics, product name "iGrantage ECS-401GX type") under the following conditions to form a writing feel improving layer having a thickness of 4.0 μm on the substrate, thereby obtaining a writing feel improving sheet. [UV irradiation conditions] Light source: high-pressure mercury lamp Lamp power: 2 kW Conveyor speed: 4.23 m / min Illuminance: 300 mW / cm ２ ・Light intensity: 250mJ / cm ２

[0116] A touch pen with a hard felt tip (Felt; manufactured by Wacom Co., Ltd., product name "ACK-20003", pen tip diameter: 0.5 mm) was selected as a writing implement for the writing feel improvement sheet.

[0117] Example 2 A writing feel improving sheet was produced in the same manner as in Example 1. A touch pen with a polyacetal nib (POM; manufactured by Wacom Co., Ltd., product name "ACK-20001", nib diameter: 0.5 mm) was selected as a writing implement for the writing feel improving sheet.

[0118] Example 3 A writing feel improving sheet was produced in the same manner as in Example 1. A touch pen with an elastomer nib (elastomer; manufactured by Wacom Co., Ltd., product name "ACK-20004", nib diameter: 0.5 mm) was selected as a writing implement for the writing feel improving sheet.

[0119] Comparative Example 1 A mixture of 100 parts by mass of a polyfunctional urethane acrylate (A1; manufactured by Arakawa Chemical Industries, Ltd., product name "Beamset 575CB", containing a photopolymerization initiator) as an active energy ray-curable component (urethane acrylate-based prepolymer) and 4.0 parts by mass of fine particles (B3; manufactured by Momentive Performance Materials Japan, Inc., product name "Tospearl 145L", average particle size: 4.5 μm, refractive index: 1.43) made of silicone resin (a silicon-containing compound having an intermediate structure between inorganic and organic) as a filler was used. Parts by mass of silica nanoparticles, 20.0 parts by mass of organosilica sol (B2; manufactured by Nissan Chemical Industries, Ltd., product name "MIBK-ST", average particle size 10 nm) as silica nanoparticles, 0.5 parts by mass of fluorine-based resin (manufactured by DIC Corporation, product name "Megafac RS-90") as a slip agent, and 0.2 parts by mass of polyether-modified silicone (E1; manufactured by Dow-Toray Industries, Inc., product name "SH28") as a silicone-based leveling agent were mixed in propylene glycol monomethyl ether to obtain a coating liquid of a coating composition.

[0120] Using the coating liquid obtained above, a writing feel improving sheet was produced in the same manner as in Example 1. A touch pen with an elastomer nib (elastomer; manufactured by Wacom Co., Ltd., product name "ACK-20004", nib diameter: 0.5 mm) was selected as a writing implement for the writing feel improving sheet.

[0121] Comparative Example 2 100 parts by mass of an organic-inorganic hybrid resin (A2; manufactured by Arakawa Chemical Industries, Ltd., product name "Opstar Z7530", a mixture of a substance obtained by bonding acryloyl groups to silica fine particles (CV value: 28%) with an average particle size of 50 nm and a polyfunctional (meth)acrylate monomer, containing a photopolymerization initiator) as an active energy ray-curable component, 0.3 parts by mass of crosslinked polymethyl methacrylate spherical fine particles (B4; manufactured by Sekisui Plastics Co., Ltd., product name "Techpolymer SSX-101", average particle size: 1.5 μm, refractive index: 1.49) as a filler, 0.1 parts by mass of a fluorine-containing adamantane derivative having a polymerizable group (E2; manufactured by Neos Co., Ltd., product name "Ftergent 602A") as a fluorine-based leveling agent, and an acrylic resin having a carboxyl group and a hydroxyl group in the side chain (manufactured by Kyoeisha Chemical Co., Ltd., product name "Florene" as an additive (dispersant). 0.1 parts by mass of propylene glycol monomethyl ether was mixed with 0.1 parts by mass of propylene glycol monomethyl ether to obtain a coating liquid for the coating composition.

[0122] Using the coating liquid obtained above, a writing feel improving sheet was produced in the same manner as in Example 1. A touch pen with an elastomer nib (elastomer; manufactured by Wacom Co., Ltd., product name "ACK-20004", nib diameter: 0.5 mm) was selected as a writing implement for the writing feel improving sheet.

[0123] Here, the formulations (solid content equivalent) of each coating composition when the active energy ray-curable component is taken as 100 parts by mass are shown in Table 1. Details of the abbreviations and the like shown in Table 1 are as follows. [Active energy ray-curable components] A1: Multifunctional urethane acrylate (manufactured by Arakawa Chemical Industries, Ltd., product name "Beamset 575CB", photopolymerization initiator included) A2: Organic-inorganic hybrid resin (manufactured by Arakawa Chemical Industries, Ltd., product name "Opstar Z7530", a mixture of a substance obtained by bonding acryloyl groups to silica fine particles (CV value: 28%) with an average particle size of 50 nm and a multifunctional (meth)acrylate monomer, photopolymerization initiator included) [Filler] B1: Microparticles made of silicone resin (silicon-containing compound having an intermediate structure between inorganic and organic) (manufactured by Momentive Performance Materials Japan, product name "Tospearl 1100", average particle size: 11.0 μm, refractive index: 1.43) B2: Organosilica sol (manufactured by Nissan Chemical Industries, Ltd., product name "MIBK-ST", average particle size 10 nm) B3: Microparticles made of silicone resin (a silicon-containing compound with an intermediate structure between inorganic and organic) (manufactured by Momentive Performance Materials Japan, product name "Tospearl 145L", average particle size: 4.5 μm, refractive index: 1.43) B4: Crosslinked polymethyl methacrylate spherical microparticles (manufactured by Sekisui Plastics Co., Ltd., product name "Techpolymer SSX-101", average particle size: 1.5 μm, refractive index: 1.49) [Leveling agents] E1: Polyether-modified silicone (manufactured by Dow Toray, product name "SH28") E2: Fluorine-containing adamantane derivative with polymerizable group (manufactured by Neos, product name "Ftergent 602A")

[0124] [Test Example 1] (Obtaining Vibration Strength) The substrate side of the writing feel improving sheet produced in the Examples and Comparative Examples was attached to one side of a glass plate (thickness: 1.2 mm) via a double-sided adhesive sheet, and this was used as a measurement sample.

[0125] An accelerometer (PCB PIEZOTORONICS, product name "356A32 / NC") was attached to the arm (which moves up and down in response to frictional vibrations during writing) holding the writing tool of the static and dynamic friction tester (Trinity Labs, product name "Tribomaster TL201Ts") used in this test example, on the opposite side of the writing tool's movement direction (relative movement direction), between the held writing tool and the base of the arm (on the main body side of the static and dynamic friction tester), at a position 2 cm from the center of the held writing tool.The static and dynamic friction tester is equipped with a measurement cart, which, when used, moves back and forth linearly in a predetermined direction while maintaining the horizontality of the installation surface of the measurement sample.

[0126] The measurement sample was placed on the measurement cart of the static and dynamic friction tester so that the surface on the writing feel improving layer side (touch pen contact surface) was facing up. Subsequently, the touch pen selected in each example was fixed to the static and dynamic friction tester so that the pen tip was in contact with the touch pen contact surface. At this time, the touch pen was fixed at an angle so that the angle between the touch pen and the touch pen contact surface was 45°. Then, the rear end side of the touch pen was tilted to the opposite side of the traveling direction of the measurement cart, and the touch pen (tilted direction) in plan view was parallel to the traveling direction.

[0127] Next, with a load of 200 g applied to the touch pen, the measurement cart described above was moved at a speed of 16.6 mm / sec, causing the touch pen to slide linearly on the touch pen contact surface (sliding distance: 100 mm). At this time, the power change caused by the acceleration of the vibration in the same direction as the sliding direction of the touch pen was detected by an accelerometer, and a power value-time chart was obtained. Then, a fast Fourier transform was performed on the power value-time chart obtained from the start of sliding to a sliding distance of 100 mm, and a chart of acceleration (vibration intensity)-period was obtained. This fast Fourier transform was performed using an FFT analyzer (manufactured by OROS, product name "OR34J-4").

[0128] From the obtained vibration intensity-period chart, the vibration intensity (mm / s) in each frequency range of 0 to 50 Hz, 50 to 100 Hz, 0 to 200 Hz, 200 to 400 Hz, 400 to 1000 Hz, and 1000 to 2000 Hz was calculated. ２ The average, maximum, minimum and standard deviation of the values ​​were obtained. The results are shown in Table 2.

[0129] The average, maximum, minimum, and standard deviation of vibration intensity in each frequency range were also obtained in the same manner as above for the surface of "Campus (registered trademark) loose-leaf" paper manufactured by Kokuyo S&T Co., Ltd., which was selected as the reference paper. The results are shown in Table 2.

[0130] [Test Example 2] (Measurement of surface roughness) For the surface of the writing feel improving layer side of the writing feel improving sheets manufactured in the Examples and Comparative Examples, the arithmetic mean surface roughness Ra (μm) and the ten-point mean surface roughness Rzjis (μm) were measured using a contact type roughness meter (manufactured by Mitutoyo Corporation, product name "SV3000S4") in accordance with JIS B0601:2013. The results are shown in Table 3.

[0131] The arithmetic mean surface roughness Ra (μm) and ten-point mean surface roughness Rzjis (μm) of the surface of "Campus (registered trademark) Loose-leaf" paper manufactured by Kokuyo S&T Co., Ltd., which was selected as the reference paper, were also measured in the same manner as above. The results are shown in Table 3.

[0132] Test Example 3 (Measurement of waviness of maximum rolling circle height) For the surface of the writing feel improving layer side of the writing feel improving sheets manufactured in the Examples and Comparative Examples, the waviness of maximum rolling circle height (μm) was measured using a contact type roughness meter (manufactured by Mitutoyo Corporation, product name "SV3000S4") in accordance with JIS B0610:2001. The results are shown in Table 3.

[0133] The rolling circle maximum height waviness (μm) was also measured in the same manner as above for the surface of "Campus (registered trademark) loose-leaf" paper manufactured by Kokuyo S&T Co., Ltd., which was selected as the reference paper. The results are shown in Table 3.

[0134] [Test Example 4] (Measurement of Friction Coefficient) Using the same static and dynamic friction measuring device as in Test Example 1, the writing feel improving sheet and the touch pen were set in the same manner as in Test Example 1. Then, with a load of 200 g applied to the touch pen, the measurement cart was moved at a speed of 16.6 mm / sec to cause the touch pen to slide on the touch pen contact surface (sliding distance: 100 mm), and the static and dynamic friction coefficients were calculated based on the friction force measured at that time. The results are shown in Table 3.

[0135] Furthermore, measurements were also carried out in the same manner as above for the combination of "Campus (registered trademark) Loose-leaf" paper manufactured by Kokuyo S&T Co., Ltd., selected as the standard paper, and "Uni (registered trademark) 2B" pencil manufactured by Mitsubishi Pencil Co., Ltd., selected as the standard pencil (standard pencil), and the combination of the above standard paper and "Uni (registered trademark) 4B" pencil manufactured by Mitsubishi Pencil Co., Ltd., selected as the reference pencil (reference pencil), to derive the static and dynamic coefficients of friction. The results are shown in Table 3.

[0136] Test Example 5 (Contact Angle Measurement) The contact angle of oleic acid on the surface of the writing feel improving layer of the writing feel improving sheets produced in the Examples and Comparative Examples was measured under the following conditions using a contact angle measuring meter (manufactured by Kyowa Interface Science Co., Ltd., product name "DM-701"). Note that oleic acid manufactured by Tokyo Chemical Industry Co., Ltd. was used as the oleic acid. The results are shown in Table 3. - Amount of oleic acid droplet: 2 μl - Measurement time: 3 seconds after dropping - Image analysis method: θ / 2 method

[0137] In the same manner as above, the water contact angle on the surface of the writing feel improving layer of the writing feel improving sheets manufactured in the Examples and Comparative Examples was measured under the following conditions. The results are shown in Table 3. Water droplet volume: 2 μl Measurement time: 3 seconds after dropping Image analysis method: θ / 2 method

[0138] [Test Example 6] (Measurement of surface free energy) The contact angles of various liquid droplets on the surface of the writing feel improving layer of the writing feel improving sheets produced in the Examples and Comparative Examples were measured, and the surface free energy (mJ / m) was calculated based on the measured values ​​according to the Kitazaki-Hata theory. ２) was measured. The contact angle was measured using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd., product name "DM-701") by the sessile drop method in accordance with JIS R3257. For the droplets, diiodomethane was used as the "dispersion component" and 1-bromonaphthalene as the "dipole component" and distilled water as the "hydrogen bond component". The results are shown in Table 3.

[0139] [Test Example 7] (Measurement of haze value) The haze value (%) of the writing feel improving sheets produced in the examples and comparative examples was measured using a haze meter (manufactured by Nippon Denshoku Industries Co., Ltd., product name "NDH-5000") in accordance with JIS K7136: 2000. The results are shown in Table 3.

[0140] [Test Example 8] (Principal Component Analysis) The four corners (areas that do not affect the measurement) of the substrate side of a reference paper (Campus (registered trademark) loose-leaf paper from KOKUYO S&T Co., Ltd.) and the writing feel improving sheets produced in the Examples and Comparative Examples were attached to one side of a glass plate (thickness: 1.2 mm) via double-sided adhesive tape, and these were used as samples.

[0141] Twenty panelists wrote on the reference paper of the above sample using a standard pencil ("Uni (registered trademark) 2B" manufactured by Mitsubishi Pencil Co., Ltd.) and a reference pencil ("Uni (registered trademark) 4B" manufactured by Mitsubishi Pencil Co., Ltd.) The same 20 panelists wrote on the writing feel improvement sheets of the above sample using the touch pen selected for each example.

[0142] Each panelist evaluated the sensory evaluation items of writing comfort, pitch, pleasantness of sound, smoothness, softness, slipperiness, vibration, smoothness, and lightness on a 5-point scale (1 to 5). The average scores of the 20 panelists are shown in Table 4.

[0143] The sensory evaluation items were evaluated on a five-point scale (1 to 5) as follows, with the writing feel when writing with a reference pencil on reference paper being assigned a rating of "3." The "writing comfort" was evaluated as a value closer to 1 if the writing comfort was perceived to be worse than that of the reference pencil and reference paper, and a value closer to 5 if the writing comfort was perceived to be better than that of the reference pencil and reference paper. The "pitch" was evaluated as a value closer to 1 if the sound was perceived to be lower than that of the reference pencil and reference paper, and a value closer to 5 if the sound was perceived to be higher than that of the reference pencil and reference paper. The "sound pleasantness" was evaluated as a value closer to 1 if the sound was perceived to be less pleasant (more harsh) than that of the reference pencil and reference paper, and a value closer to 5 if the sound was perceived to be more pleasant than that of the reference pencil and reference paper. The "smoothness" was evaluated as a value closer to 1 if the feeling of unevenness was stronger than that of the reference pencil and reference paper, and a value closer to 5 if the feeling of smoothness was stronger than that of the reference pencil and reference paper. The "softness" was evaluated as a value closer to 1 if the feeling of hardness was stronger than that of the reference pencil and reference paper, and a value closer to 5 if the feeling of softness was stronger than that of the reference pencil and reference paper. The closer to 1 the "slipperiness" feels that the pencil has a stronger grip than the reference pencil and paper, and the closer to 5 the closer to 5 the slipperier it feels than the reference pencil and paper. The closer to 1 the "vibration" feels that the pencil has a stronger roughness than the reference pencil and paper, and the closer to 5 the closer to 5 the smoother it feels than the reference pencil and paper. The closer to 1 the "smoothness" feels that the pencil has a stronger firmness than the reference pencil and paper, and the closer to 5 the closer to 5 the smoother it feels than the reference pencil and paper. The closer to 1 the "lightness" feels that the pencil has a heavier writing feel than the reference pencil and paper, and the closer to 5 the closer to 5 the lighter it feels than the reference pencil and paper.

[0144] Next, the sensory evaluation data obtained above and the average values ​​(mm / s) of the vibration intensities in the frequency ranges of 0 to 50 Hz, 50 to 100 Hz, 0 to 200 Hz, 200 to 400 Hz, 400 to 1000 Hz, and 1000 to 2000 Hz obtained in Test Example 1 were used. ２Using the data of the arithmetic mean surface roughness Ra (nm) and ten-point mean surface roughness Rzjis (μm) obtained in Test Example 2, the rolling circle maximum height waviness (μm) obtained in Test Example 3, and the static and dynamic friction coefficients obtained in Test Example 4, principal component analysis was performed to extract the first and second principal components, and the center of gravity of the reference paper and reference pencil (reference center of gravity), the center of gravity of the reference paper and reference pencil (reference center of gravity), and the center of gravity of each writing feel improvement sheet were obtained. In performing this principal component analysis, as a preprocessing step, scaling was performed by subtracting the average value from each data value and then dividing by the standard deviation, and the scaled data was used. The coordinates of the obtained center of gravity (coordinates of a two-dimensional graph with the first principal component on the X axis and the second principal component on the Y axis) are shown in Table 2. The distance (center-of-gravity distance) between the reference center of gravity obtained above and the center of gravity of each writing feel improvement sheet was then calculated. The distance between the center of gravity of the standard obtained above and the center of gravity of the reference (center-to-center distance) was also calculated. The results are shown in Table 3.

[0145] Table 5 shows the weight (degree of influence) of each data item in the first principal component and the weight (degree of influence) of each data item in the second principal component calculated by the above principal component analysis.

[0146] Here, when determining whether or not an arbitrary writing feel improvement sheet satisfies the distance between centers of gravity specified in this embodiment, it is preferable to perform principal component analysis using each data of the arbitrary writing feel improvement sheet, each data of the reference paper and reference pencil, each data of the reference paper and reference pencil, and each data of the writing feel improvement sheets (five types) manufactured in this embodiment and comparative example.

[0147] [Test Example 9] (Sensory Evaluation of Writing Feel) The absolute value of the difference between the average score (rating) of the 20 panelists' evaluations of "good writing comfort" among the sensory evaluation items obtained in Test Example 8 and the standard value of "3" for the sensory evaluation was calculated. The smaller the absolute value of this difference, the closer the writing feel is to that of writing with a pencil on paper. Based on the calculated absolute value of the difference, a sensory evaluation of the writing feel was performed according to the following criteria. The results are shown in Table 3. ◎: Absolute value of difference is less than 0.8 ○: Absolute value of difference is 0.8 or more but less than 1.2 △: Absolute value of difference is 1.2 or more but less than 2.0 ×: Absolute value of difference is more than 2.0

[0148] Test Example 10 (Evaluation of Antiglare Properties) The substrate side of the writing experience improving sheet produced in the Examples and Comparative Examples was attached to one side of a black board (product name "Acrylite", manufactured by Yuko Shoko Co., Ltd.) via a double-sided adhesive sheet. A three-wavelength fluorescent lamp was turned on above the resulting laminate of the writing experience improving sheet and the black board, and the light was reflected by the writing experience improving sheet. The reflected light was visually observed, and the antiglare properties were evaluated according to the following criteria. The results are shown in Table 3. ◯: The outline of the fluorescent lamp was blurred when visible due to reflection by the writing experience improving sheet. ×: The outline of the fluorescent lamp was not blurred when visible due to reflection by the writing experience improving sheet.

[0149]

[0150]

[0151]

[0152]

[0153]

[0154] As can be seen from Table 3, the writing feel improving sheets produced in the examples were excellent in writing feel with a touch pen, and a writing feel similar to that of writing with a pencil on paper was obtained. In addition, the writing feel improving sheets produced in the examples were also excellent in antiglare properties.

[0155] The writing feel improving sheet of the present invention is suitably used as the outermost layer of a touch panel on which a touch pen is used.

[0156] 1... Writing feel improving sheet 11... Base material 12... Writing feel improving layer

Claims

1. A writing feel improving sheet having a surface that is contacted by a touch pen, wherein after the tip of a specified touch pen is brought into contact with the surface that is contacted by the touch pen, a load of 200 g is applied to the touch pen, the angle between the touch pen and the surface is maintained at 45°, and the touch pen is slid linearly at a speed of 16.6 mm / s while detecting a change in power caused by the acceleration of vibration in the same direction as the sliding direction of the touch pen with an accelerometer, and a chart of power value-time obtained from the start of the sliding to a sliding distance of 100 mm is subjected to a fast Fourier transform, and the average value of vibration intensity in a frequency range of 50 to 100 Hz obtained from the obtained vibration intensity-period chart is 1.2 mm / s. ２ A writing feel improving sheet characterized by the above.

2. The average value of vibration intensity in the frequency range of 0 to 200 Hz obtained from the vibration intensity-period chart is 10 mm / s ２ The writing feel improving sheet according to claim 1, characterized in that:

3. The writing feel improving sheet as described in claim 1, characterized in that the coefficient of dynamic friction measured by contacting the tip of a specified touch pen with the surface of the writing feel improving sheet that the touch pen comes into contact with, applying a load of 200 g to the touch pen and sliding the touch pen linearly at a speed of 16.6 mm / s while maintaining the angle between the touch pen and the surface at 45°, is 0.01 or more and 0.41 or less.

4. The writing feel improving sheet as described in claim 1, characterized in that the static friction coefficient measured by contacting the tip of a specified touch pen with the surface of the writing feel improving sheet that the touch pen comes into contact with, applying a load of 200 g to the touch pen and sliding the touch pen linearly at a speed of 16.6 mm / s while maintaining the angle between the touch pen and the surface at 45°, is 0.01 or more and 0.49 or less.

5. The writing feel improving sheet according to claim 1, characterized in that the arithmetic mean roughness Ra of the surface of the writing feel improving sheet that comes into contact with the touch pen is 0.2 μm or more and 10 μm or less.

6. The writing feel improving sheet according to claim 1, characterized in that the ten-point mean roughness Rzjis of the surface of the writing feel improving sheet that comes into contact with the touch pen is 3 μm or more and 10 μm or less.

7. The sheet for improving the writing feel according to claim 1, comprising a base material and a writing feel improving layer with which the touch pen comes into contact.

8. The writing feel improving sheet according to claim 7, characterized in that the writing feel improving layer is a layer formed by curing a coating composition containing a curable component and a filler.