JP2023133076A - Sheet, article, decorative sheet, decorative material, and curable composition - Google Patents

Abstract

To provide a sheet that can achieve both of matte property and scratch resistance.SOLUTION: Provided is a sheet 10 having a surface layer 1, wherein: one surface S1 of the surface layer has a surface shape having a wrinkled structure; RSm (average length of curved line elements) of the surface shape, which is a parameter in a lateral direction of a profile curved line as stipulated in JIS B0601:2013, is 50 μm or less; and the surface layer contains a polymer having a first repeating unit that includes a ring structure and a second repeating unit that includes a polyoxyalkylene group.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to sheets, articles, decorative sheets, decorative materials, and curable compositions.

BACKGROUND ART In various articles such as building materials such as interior materials and exterior materials, and display devices, a matte film may be disposed on the surface for the purpose of imparting matte properties and protection.

As a matte film, a film having a matte layer containing a resin and particles (matting agent) is known, for example, as described in Patent Document 1. Furthermore, as described in Patent Document 2, for example, as a method for forming irregularities on a film surface, a method is known in which a curable composition is irradiated with excimer light to form a wrinkle-like uneven structure on a cured film. ing.

Patent No. 3703133 JP2022-25623A

Films placed on the surfaces of various articles are also required to have scratch resistance.

In a matte film having a matte layer containing the above-mentioned resin and particles (matting agent), the matte effect is obtained due to the light diffusion effect of the particles themselves. When using particles (matting agent), it is necessary to increase the amount of particles used in order to enhance the matting effect. However, as the amount of particles used increases, the particles tend to fall off from the matte layer when the surface of the matte layer is rubbed. Therefore, the scratch resistance decreases. In addition, surface performance tends to deteriorate, such as scratches becoming more noticeable due to changes in gloss due to missing particles. On the other hand, if the amount of particles used is reduced in order to suppress deterioration in surface performance, the matting effect tends to decrease. Therefore, surface performance and matte effect are in an antinomic relationship.

Furthermore, in the method of forming a wrinkled uneven structure on the cured film by irradiating the curable composition with excimer light, the wrinkled uneven structure provides a matting effect. In this case, in order to increase the scratch resistance, a polyfunctional polymerizable compound is used in the curable composition, the content of the polyfunctional polymerizable compound is increased, or the number of functional groups in the polyfunctional polymerizable compound is increased. It is possible that However, if the content of the polyfunctional polymerizable compound is increased or the number of functional groups in the polyfunctional polymerizable compound is increased, it becomes difficult to form a wrinkle-like uneven structure, and the matting effect tends to decrease. be. Therefore, in this case as well, surface performance and matte effect are in an antinomic relationship.

Furthermore, when the curable composition is an ultraviolet curable composition or an electron beam curable composition, there is a problem that the curing is easily inhibited by oxygen, the surface hardness decreases, and good scratch resistance cannot be obtained. be.

The present disclosure has been made in view of the above problems, and its main purpose is to provide a sheet that is both matte and scratch resistant.

An embodiment of the present disclosure is a sheet having a surface layer, wherein one surface of the surface layer has a surface shape having a wrinkle structure, and the surface shape has a contour curve defined in JIS B0601:2013. RSm (average length of curved elements), which is a lateral parameter, is 50 μm or less, and the surface layer has a first repeating unit containing a cyclic structure and a second repeating unit containing a polyoxyalkylene group. A sheet containing a polymer is provided.

Other embodiments of the present disclosure provide an article having a sheet as described above on a surface thereof.

Other embodiments of the present disclosure provide a decorative sheet having the sheet described above.

Another embodiment of the present disclosure provides a decorative material having an adherend and the above-mentioned decorative sheet disposed on one surface of the adherend.

Another embodiment of the present disclosure is a curable composition used for a surface layer having a surface shape having a wrinkled structure, the composition comprising a first polymerizable compound containing a cyclic structure and a second polymerizable compound containing a polyoxyalkylene group. Provided is a curable composition containing a curable compound.

The present disclosure has the advantage of being able to provide a sheet that is both matte and scratch resistant.

FIG. 1 is a schematic cross-sectional view illustrating a sheet in the present disclosure. It is an example of the microscopic image of the surface layer surface of the sheet|seat in this indication. FIG. 1 is a schematic cross-sectional view illustrating a sheet according to a first aspect of the present disclosure. FIG. 1 is a schematic cross-sectional view illustrating a sheet according to a first aspect of the present disclosure. FIG. 2 is a schematic cross-sectional view illustrating a sheet according to a second aspect of the present disclosure. FIG. 2 is a schematic cross-sectional view illustrating a sheet according to a second aspect of the present disclosure. FIG. 1 is a schematic cross-sectional view illustrating an article according to a first embodiment of the present disclosure. FIG. 2 is a schematic cross-sectional view illustrating an article according to a second embodiment of the present disclosure.

Embodiments will be described below with reference to the drawings and the like. However, the present disclosure can be implemented in many different ways and should not be limited to what is described in the embodiments illustrated below. In addition, in order to make the explanation clearer, the drawings may schematically represent the width, thickness, and shape of each part compared to the actual form, but this is only an example and should be interpreted in a limited manner. isn't it.

In this specification, when expressing a mode in which another member is placed on top of a certain member, when it is simply expressed as "above" or "below", unless otherwise specified, it means that the member is in contact with a certain member. This includes both cases in which another member is placed directly above or below a certain member, and cases in which another member is placed above or below a certain member via another member. In addition, in this specification, when expressing a mode in which another member is placed on the surface of a certain member, when it is simply expressed as "on the surface" or "on the surface side", unless otherwise specified, it refers to the arrangement of another member on the surface of a certain member. This includes both a case where another member is placed directly above or below a certain member, and a case where another member is placed above or below a certain member via another member.

Further, in this specification, the terms "plate," "sheet," and "film" are not distinguished from each other based solely on the difference in designation. For example, the term "sheet" also includes members called "plates" or "films."

Hereinafter, the sheet, article, decorative sheet, decorative material, and curable composition in the present disclosure will be described in detail.

A. Sheet The sheet in the present disclosure is a sheet having a surface layer, in which one surface of the surface layer has a surface shape having a wrinkle structure, and the surface shape has a horizontal contour curve defined in JIS B0601:2013. RSm (average length of curved elements), which is a directional parameter, is 50 μm or less, and the surface layer has a first repeating unit containing a cyclic structure and a second repeating unit containing a polyoxyalkylene group. Contains union.

FIG. 1 is a schematic cross-sectional view illustrating a sheet in the present disclosure. FIG. 2 is a microscopic image of the surface layer of the sheet according to the present disclosure. The sheet 10 shown in FIG. 1 has a surface layer 1, and one surface S1 of the surface layer 1 has a surface shape having a wrinkled structure. Furthermore, the surface layer 1 contains a polymer having a first repeating unit containing a cyclic structure and a second repeating unit containing a polyoxyalkylene group.

According to the sheet of the present disclosure, since the surface layer has a wrinkle structure on one surface, light reflection can be suppressed due to the light diffusion effect at the refractive index difference interface between the surface layer and air. This produces a matte effect.

Further, RSm (average length of curve elements) is a parameter in the horizontal direction of the contour curve, and is the average length of the contour curve elements at the reference length. The smaller Rsm is, the more convex portions are included in the reference length. According to the sheet according to the present disclosure, since RSm is equal to or less than a predetermined value, the convex portions are densely present. Therefore, the matting effect can be improved.

Here, as will be described later, when the curable composition is cured to form a surface layer, if the curable composition is irradiated with short wavelength ultraviolet rays, the energy of the ultraviolet rays will penetrate only into the surface area. Since the energy does not reach the lower layers, only the surface portion begins to harden. Therefore, it is thought that the wrinkle structure is formed by curing shrinkage only on the surface. When the polymer contained in the surface layer has a second repeating unit containing a polyoxyalkylene group, a flexible portion is introduced by the polyoxyalkylene group. Therefore, it is presumed that curing and shrinkage only in the surface portion progresses sufficiently. Therefore, according to the sheet of the present disclosure, the polymer contained in the surface layer has a second repeating unit containing a flexible polyoxyalkylene group, thereby stabilizing the formation of wrinkles and improving the matting effect. be able to.

Further, according to the sheet of the present disclosure, since the polymer contained in the surface layer has the first repeating unit including a rigid annular structure, the hardness and strength of the surface layer can be increased. Furthermore, since the polymer contained in the surface layer has a second repeating unit containing a polyoxyalkylene group, it is possible to suppress curing inhibition caused by oxygen when curing the curable composition to form the surface layer. . Since hydrogen atoms are easily extracted from polyoxyalkylene groups, even if peroxy radicals are generated, hydrogen atoms are easily donated to generate radicals. Therefore, curing inhibition caused by oxygen can be suppressed. Therefore, the surface hardness of the surface layer can be increased. Therefore, when the surface layer contains a polymer having a first repeating unit containing a cyclic structure and a second repeating unit containing a polyoxyalkylene group, the scratch resistance of the surface layer can be improved. Therefore, excellent scratch resistance can be obtained without increasing the amount of the polyfunctional polymerizable compound or increasing the number of polyfunctional functional groups.

As described above, according to the sheet of the present disclosure, it is possible to achieve both matte properties and scratch resistance. Further, in the present disclosure, since a matte effect is exhibited, a low gloss feeling can be obtained, and not only can design properties be imparted to the sheet, but also anti-glare properties can be obtained.

Each structure of the sheet in the present disclosure will be described below.

1. Surface Layer In the present disclosure, one surface of the surface layer has a surface shape having a wrinkled structure. Further, RSm (average length of curved elements), which is a horizontal parameter of the contour curve defined in JIS B0601:2013 for surface shape, is 50 μm or less. Note that, hereinafter, the above-mentioned surface shape may be referred to as a specific surface shape. Moreover, the surface layer contains a polymer having a first repeating unit containing a cyclic structure and a second repeating unit containing a polyoxyalkylene group.

When the sheet according to the present disclosure has a laminated structure, it is preferable to have a surface layer as the outermost layer. That is, it is preferable that the outermost surface of the sheet has the above-mentioned surface shape.

(1) Surface shape The surface shape of the surface layer in the present disclosure has a wrinkled structure. Moreover, RSm of the surface shape is within a predetermined range.

(a) Shape of wrinkle structure In the surface shape of the surface layer in the present disclosure, the shape of the wrinkle structure is not particularly limited as long as RSm is within a predetermined range, but it is preferable that the wrinkle structure has the following shape.

Preferably, the wrinkle structure has an uneven shape due to irregular wrinkles. It is preferable that the irregular wrinkles include a plurality of protrusions formed by a plurality of protrusions and a recess formed surrounded by the plurality of protrusions. Moreover, it is preferable that the protrusion has a linear protrusion.

In this specification, the term "striated protrusion" refers to a protrusion having a ratio of length to width (length/width) of 3 or more, preferably 5 or more, and more preferably 10 or more. means. The method for determining the length and width of the protrusion will be described later. Hereinafter, the filamentous protrusion may be referred to as a filamentous protrusion.

A specific embodiment of the wrinkle structure includes, for example, the embodiment shown in FIG. 2. FIG. 2 shows that the surface shape of the surface layer has irregular wrinkles in plan view; the irregular wrinkles include a plurality of convex portions 3 formed by a plurality of curved linear protrusions; It has a recess 2 surrounded by a plurality of protrusions (a plurality of protrusions 3); at least a part of the plurality of curved protrusions 3 is formed by a meandering linear protrusion, and meandering. It is also shown that a meandering recess 2 is formed so as to be surrounded by the linear protrusions. When the surface shape of the surface layer has a wrinkled structure composed of irregular wrinkles as shown in FIG. 2, the matting effect is improved.

Here, "curved" means having one or more portions where the extending direction of the continuous filamentous convex portions 3 is reversed from one side to the other side in plan view. Hereinafter, a portion where the extending direction of the continuous filamentous convex portions 3 is reversed from one side to the other side may be referred to as a reversed portion. An example of an inverted part is a shape having an inflection point when the width of the convex part 3 of the filament in plan view is ignored (the width is assumed to be 0) and approximated by a continuous curve. can be mentioned. Other examples of the inverted portion include a V-shaped broken line or two sides sandwiching one vertex of a triangle when the width of the convex portion 3 of the filament in plan view is approximated by a straight line. Examples include a form having a portion approximated by .

In addition, "meandering" means having two or more reversed portions in a plan view, and when the linear convex portion 3 is advanced in its extending direction, two reversed portions adjacent to each other alternately. This means that there is a portion where the extending direction of the filamentous convex portion 3 is reversed. For example, when the width of the linear convex portion 3 in plan view is approximated by a continuous curve, there is a form having a portion approximated by the Roman letter "S". Further, when the width of the linear convex portion 3 in plan view is approximated by a straight line, there may be a form having a portion approximated by the Roman letter "W".

As used herein, "irregular" means a shape that has a certain rule, or a pattern that cannot be said to be arranged according to a certain rule. A typical example of a non-irregular shape (regular shape) is a so-called lenticular lens, in which a plurality of cylindrical unit lenses are arranged adjacent to each other in a direction perpendicular to its longitudinal direction. Another example is a shape arranged with a certain periodicity in a specific direction. Therefore, in the present disclosure, irregular wrinkles that the wrinkle structure forming the surface shape of the surface layer may have are not shapes in which the shape of one protrusion itself is formed according to a certain rule such as periodicity. be irregular; the shapes of the plurality of protrusions formed by the plurality of protrusions are not formed and arranged according to a fixed rule, but are irregular; The shape of the recessed portion is also irregular;

In the wrinkle structure that forms the surface shape, the shape of one protrusion (one protrusion) itself, the shape and arrangement of each of multiple protrusions (multiple protrusions), and the recess surrounded by multiple protrusions If any of the shapes is irregular, the surface of the surface layer tends to have a specific surface shape. For the same reason, it is more preferable that all of them be irregular.

As described above, one surface of the surface layer has a wrinkled structure and substantially has an uneven shape. The convex portions and concave portions in the uneven shape are based on the median value of the height distribution in the concave and convex shape, and an area with a height exceeding the median value is defined as a convex portion, and an area with a height below the median value is defined as a concave portion. For example, by using the density difference (that is, the brightness difference) of an image that has a density that corresponds 1:1 to the surface height of the surface layer, the darkest part in the density distribution image is set to gradation 255, and the darkest part in the density distribution image is set to gradation 255. The thin portion may be defined as gradation 0, and the gradations 0 to 255 may be divided by binarization processing such that gradations 0 to 127 are concave portions and gradations 128 to 255 are convex portions. Note that in this case, the median density value for the median height value is 127.

Further, as shown in FIG. 2, for example, the wrinkle structure includes a plurality of convex portions formed by a plurality of irregular but uniform protrusions, and a concave portion surrounded by the convex portions. It is preferable to have. Therefore, in the convex portions (protrusions) shown in FIG. 2, a shape in which the width of the convex portion changes drastically or a shape in which the height of the convex portion changes extremely is a preferable aspect in order to obtain a matte effect. I can't say that. Regarding the shape of the wrinkles constituting the wrinkle structure, that is, the shape of the convex portions (protrusions) and the concave portions, specific aspects that can be effective in improving the matting effect will be described below.

The shape of the recessed portion may be acute-angled, semicircular, or semielliptical in cross-sectional view, or a combination thereof. Moreover, the shape of the recessed portion may be such that one convex portion has a recessed portion in part in a cross-sectional view.

On the other hand, the shape of the convex portion can have a semicircular or semielliptical shape in cross-sectional view, although the width may be wide or narrow.

The height of the convex portion (height of the protrusion) is, for example, preferably 0.5 μm or more, more preferably 1 μm or more, and even more preferably 2 μm or more. Further, the height of the convex portion is, for example, about 10 μm or less. Further, the width of the convex portion is, for example, preferably 0.1 μm or more, more preferably 0.3 μm or more, and still more preferably 0.5 μm or more. Further, the width of the convex portion is, for example, preferably 10 μm or less, more preferably 4 μm or less, and still more preferably 3 μm or less. When the height and width of the convex portions are within the above ranges, the matting effect is improved in relation to the concave portions.

The depth of the recess is, for example, preferably 0.5 μm or more, more preferably 1 μm or more, and still more preferably 2 μm or more. Further, the depth of the recess is, for example, approximately 10 μm or less.
Further, the width of the recess is, for example, preferably 0.1 μm or more, more preferably 0.2 μm or more, and still more preferably 0.3 μm or more. Further, the width of the recess is, for example, preferably 10 μm or less, more preferably 3 μm or less, and even more preferably 2 μm or less. When the depth and width of the recesses are within the above ranges, the matting effect is improved in relation to the projections.

The distance from the top of the convex portion to the bottom of the concave portion (height difference between the convex portion and the concave portion) is, for example, preferably 1 μm or more, more preferably 2 μm or more, and still more preferably 4 μm or more. Further, the distance is, for example, preferably 20 μm or less, more preferably 8 μm or less, and still more preferably 7 μm or less. When the distance is within the above range, the matting effect is improved.

Here, the dimensions of the protrusions are the average value of 10 arbitrary protrusions (protrusions) at 10 arbitrary locations (100 μm square area x 10 locations) on the surface of the surface layer, that is, a total of 100 protrusions. be. In addition, as shown in FIG. 2, the width of one convex part (protrusion) is not the same and there are wide and narrow widths, so the width of one convex part (protrusion) is different from the width of one convex part ( This is the average value of the widths at five arbitrary locations in the protrusion. The same applies to the height of the convex portion (protrusion) 1.

Further, the dimensions of the recessed portion are determined in the same manner as the dimensions of the above-mentioned convex portion.

The occupation ratio of the convex portion is, for example, preferably 15% or more, more preferably 20% or more, and still more preferably 30% or more. Further, the occupation ratio of the convex portion is, for example, preferably 80% or less, more preferably 70% or less, and still more preferably 60% or less. When the occupancy rate of the convex portions is within the above range, the surface of the surface layer tends to have a specific surface shape in relation to the occupancy rate of the concave portions surrounded by the convex portions, and the matting effect is improved.

Here, the occupancy rate of the convex portions is the average value of the occupancy rate of the convex portions at arbitrary 10 locations (100 μm square area x 10 locations) on the front T-plane layer.

The convex portion and the concave portion may have portions having approximately the same direction and approximately the same width, but it is preferable that the length of the portion is short. When the length is short, the surface of the surface layer tends to have a specific surface shape, and the matting effect is improved. Specifically, the continuous length of the convex portions and concave portions having substantially the same direction and substantially the same width is preferably 95 μm or less, more preferably 80 μm or less, and still more preferably 70 μm or less. Further, the length is, for example, preferably 5 μm or more, more preferably 10 μm or more, and still more preferably 15 μm or more. When the length is within the above range, the wrinkles become more irregular and the matting effect is improved.

Here, 80% or more of arbitrary 10 protrusions and depressions (i.e., a total of 100 protrusions and depressions) at 10 arbitrary locations (100 μm square area x 10 locations) on the surface layer satisfy the above conditions. It is preferably 85% or more, still more preferably 90% or more, even more preferably 95% or more.

In addition, "substantially" in "substantially the same" in this specification means substantially the same, without branching, substantially the same direction refers to within ±3°, and substantially the same width refers to within ±5%. say.

Further, the number of convex portions (protrusions) in a 100 μm square area is, for example, preferably 10 or more, more preferably 20 or more, and still more preferably 30 or more. The number of the above-mentioned convex portions is, for example, preferably 200 or less, more preferably 100 or less, and even more preferably 70 or less. When the number of the convex portions is within the above range, the surface of the surface layer tends to have a specific surface shape, and the matting effect is improved.

Here, the number of convex portions in a 100 μm square area is the average value of the number of convex portions at 10 locations (100 μm square area x 10 locations) on the surface layer.

One surface of the surface layer preferably has a wrinkled structure on at least a portion thereof, and more preferably has a wrinkled structure over the entire surface.

(c) Surface texture of wrinkled structure In the surface shape of the surface layer according to the present disclosure, as long as RSm is within a predetermined range, the surface texture of the wrinkled structure is not particularly limited, but the wrinkled structure may have the following surface texture. preferable.

(i) RSm (average length of curved elements)
As for surface properties, RSm (average length of curved elements) defined in JIS B0601:2013 is 50 μm or less. RSm (average length of curve elements) is a parameter in the horizontal direction of the contour curve, and is the average length of the contour curve elements at the reference length. The smaller Rsm is, the more convex portions are included in the reference length. Therefore, in a surface shape with a small Rsm, the apexes of the protrusions are densely present, so that the matting effect becomes large.

RSm (average length of curved elements) is preferably 47.5 μm or less, more preferably 45 μm or less. The lower limit of RSm (average length of curved elements) is preferably 20 μm or more, more preferably 22.5 μm or more, and still more preferably 25 μm or more, considering ease of manufacture.

Note that in measuring RSm (average length of curved elements) in this specification, the cutoff value is 0.8 mm. Further, in this specification, RSm (average length of a curved element) is an average value of measured values at ten arbitrary locations.

(ii) Rz (maximum height)
As for surface properties, Rz (maximum height) defined in JIS B0601:2013 is preferably 10 μm or less. Rz (maximum height) is one of the peak and height parameters of the contour curve, and is the sum of the height of the highest peak and the depth of the deepest valley in the contour curve at the reference length. The larger the value of Rz (maximum height) is, the larger (tall) the shape of the convex portions as seen from the valley (concavity) is present, and it is an index indicating that there is a tendency for more such convex portions to be present. Therefore, when Rz (maximum height) is within the above range, variations in the height of the convex portions are reduced, and a uniform matting effect is achieved.

Rz (maximum height) is more preferably 8 μm or less, still more preferably 7 μm or less. The lower limit of Rz (maximum height) is preferably 3 μm or more, more preferably 3.2 μm or more, and even more preferably 3.5 μm or more in order to develop a matte effect.

Note that in measuring Rz (maximum height) in this specification, the cutoff value is 0.8 mm. Further, in this specification, Rz (maximum height) is an average value of measured values at ten arbitrary locations.

(iii) Ra (arithmetic mean roughness)
As for the surface quality, Ra (arithmetic mean roughness) defined in JIS B0601:2013 is preferably 2 μm or less. Ra (arithmetic mean roughness) is one of the parameters in the height direction of the contour curve, and is the average value of the height difference from the average plane in the contour curve at the reference length. Ra (arithmetic mean roughness) is one of the parameters in the height direction of the contour curve, and is the average value of the height difference from the average plane in the contour curve at the reference length. This is an index that indicates that the smaller the value of Ra (arithmetic mean roughness), the smaller the difference in height between the convex portions in the surface shape and the corresponding concave portions, resulting in a smoother and more uniform shape. be. Therefore, when Ra (arithmetic mean roughness) is within the above range, the shape of the convex portions in the surface shape becomes more uniform and gentle, and a uniform matting effect is exhibited.

Ra (arithmetic mean roughness) is more preferably 1.9 μm or less, still more preferably 1.8 μm or less. The lower limit of Ra (arithmetic mean roughness) is preferably 0.1 μm or more, more preferably 0.4 μm or more, and still more preferably 0.6 μm or more in order to improve the matting effect.

Note that in measuring Ra (arithmetic mean roughness) in this specification, the cutoff value is 0.8 mm. Moreover, in this specification, the above-mentioned Ra (arithmetic mean roughness) is an average value of measured values at ten arbitrary locations.

(iv) Spc (arithmetic mean curvature of protrusion apex)
As for the surface quality, it is preferable that the Spc (arithmetic mean curvature of the apex of the projection) defined in JIS B0601:2013 is 8000 mm ⁻¹ or less. Spc (arithmetic mean curvature of the apex of a protrusion) is one of the three-dimensional surface texture parameters specified in JIS B0601:2013, and is a 3D surface texture parameter defined in JIS B0601:2013. This is the average curvature (average sharpness) of the tip of the mountain peak, which is determined from the arithmetic mean value of the radius of curvature of the peak (peak of the protrusion). Therefore, Spc (arithmetic mean curvature of the apex of the projection) is the reciprocal (mm ⁻¹ ) of the radius (mm).

The larger the value of Spc (arithmetic mean curvature of the apex of the protrusion), the larger the curvature of the tip of the peak (convex) (the radius of curvature of the reciprocal thereof is smaller, and the shape of the tip becomes sharper). On the other hand, the smaller the value of Spc (arithmetic mean curvature of the apex of the protrusion), the smaller the curvature of the apex of the protrusion (the reciprocal radius of curvature thereof becomes larger and the shape of the tip becomes blunter). In other words, the smaller the Spc (arithmetic mean curvature of the apex of the protrusion), the more rounded the protrusion becomes and the closer it becomes to a flat surface, so the gloss becomes greater. Therefore, if the surface shape has a large Spc (arithmetic mean curvature of the apex of the protrusion) (a surface shape with a sharp apex of the protrusion), the light will be diffused more strongly on the surface, and the gloss will be reduced. On the other hand, a surface shape with a small Spc (arithmetic mean curvature of the protrusion apex) has a rounded protrusion apex, so although the matting effect is inferior when the viewer views the sheet from the front, it is The matte effect when viewing the sheet is improved. Therefore, when Spc (arithmetic mean curvature of the apex of the protrusions) is within the above range, the shape of the protrusions in the surface shape will be more gentle, and a uniform matte effect will be produced.

Spc (arithmetic mean curvature of the apex of the protrusion) is more preferably 7000 mm ^-1 or less, and even more preferably 6500 mm ^-1 or less. The lower limit of Spc (arithmetic mean curvature of the apex of the protrusion) is preferably 3000 mm ^-1 or more, more preferably 3500 mm ^-1 or more, and even more preferably 4000 mm ^-1 or more, in order to achieve a uniform matting effect.

Note that in measuring Spc (arithmetic mean curvature of the apex of the projection) in this specification, the cutoff value is 0.8 mm. Further, in this specification, Spc (arithmetic mean curvature of the apex of the protrusion) is an average value of measured values at ten arbitrary locations.

(2) Physical Properties of Surface Layer The sheet according to the present disclosure exhibits an excellent matting effect by having a surface layer with a specific surface shape. The matte effect makes it difficult to visually recognize the gloss, giving a low gloss feel and providing anti-glare properties.

The 60° gloss value of the surface having the surface shape of the surface layer is, for example, preferably 10.0 or less, more preferably 7.5 or less, still more preferably 5.0 or less, particularly preferably 4.0 or less, particularly preferably is 3.6 or less.

Here, the 60° gloss value of the surface having the surface shape of the surface layer refers to the 60° specular gloss measured in accordance with JIS K5600-4-7:1999, and is measured using, for example, a gloss meter. can do. The 60° gross value of the surface having the surface shape of the surface layer is the average value of the measured values at ten arbitrary locations.

(3) Material of Surface Layer The surface layer in the present disclosure contains a polymer having a first repeating unit containing a cyclic structure and a second repeating unit containing a polyoxyalkylene group. By containing such a polymer in the surface layer, the hardness and strength of the surface layer can be increased, and the scratch resistance can be improved.

(a) Polymer

(i) First repeating unit The first repeating unit constituting the polymer contained in the surface layer includes a cyclic structure.

(i-1) Cyclic structure Examples of the cyclic structure include an alicyclic structure, an aromatic ring structure, and a heterocyclic structure. Specifically, the cyclic structure includes an alicyclic hydrocarbon ring structure, an aromatic hydrocarbon ring structure, an alicyclic heterocyclic structure, an aromatic heterocyclic structure, and the like.

Further, the cyclic structure may be an unsaturated ring structure or a saturated ring structure. An unsaturated ring structure is a cyclic structure having an unsaturated bond within the ring. Moreover, a saturated ring structure is a cyclic structure that does not have an unsaturated bond within the ring. Among these, the cyclic structure is preferably a saturated ring structure. Since the cyclic structure does not have an unsaturated bond within the ring, deterioration of the surface layer due to ultraviolet rays, heat, etc. can be suppressed, and the weather resistance of the surface layer can be improved.

Further, the cyclic structure may be a monocyclic structure or a polycyclic structure. In the case of a polycyclic structure, the cyclic structure may be a fused ring structure or a spirocyclic structure. Among these, it is preferable that the cyclic structure is not a bridged ring structure. A bridged ring structure is a cyclic structure having a bridged structure within the ring. In a bridged ring structure, the rings are less likely to interact with each other. Therefore, if the cyclic structure is not a bridged ring structure, even if it does not contain a π bond like an aromatic ring structure, interactions between the rings can occur, increasing the strength and strength of the surface layer. It is thought that it can be increased.

Moreover, it is preferable that the annular structure has high planarity. As described above, the interaction between the rings can be enhanced, and the strength and strength of the surface layer can be improved.

Further, the cyclic structure may be substituted or unsubstituted.

Examples of the alicyclic hydrocarbon ring structure include a cycloalkane ring structure and a cycloalkene ring structure. Examples of the cycloalkane ring structure include cycloalkane ring structures having 3 to 20 ring members. Specifically, the cycloalkane ring structure includes a cyclopropane ring structure, a cyclobutane ring structure, a cyclopentane ring structure, a cyclohexane ring structure, a cycloheptane ring structure, a cyclooctane ring structure, a cyclodecane ring structure, a cyclododecane ring structure, etc. can be mentioned. Examples of the cycloalkene ring structure include cycloalkene ring structures having 3 to 20 ring members. Specific examples of the cycloalkene ring structure include a cyclopropene ring structure, a cyclobutene ring structure, a cyclopentene ring structure, a cyclohexene ring structure, a cycloheptene ring structure, a cyclohexadiene ring structure, and a cyclooctadiene ring structure.

Among these, the alicyclic hydrocarbon ring structure may be an unsaturated ring structure or a saturated ring structure, as described above, but a saturated ring structure is preferable. That is, the alicyclic hydrocarbon ring structure may be an unsaturated alicyclic hydrocarbon ring structure or a saturated alicyclic hydrocarbon ring structure, but it may be a saturated alicyclic hydrocarbon ring structure. It is preferable that there be. Examples of the saturated alicyclic hydrocarbon ring structure include the above-mentioned cycloalkane ring structure.

Moreover, as mentioned above, it is preferable that the alicyclic hydrocarbon ring structure is not a bridged ring structure.
Furthermore, as mentioned above, it is preferable that the alicyclic hydrocarbon ring structure has high planarity among the alicyclic hydrocarbon ring structures.

Therefore, the alicyclic hydrocarbon ring structure is preferably a saturated alicyclic hydrocarbon ring structure, and more preferably a monocyclic saturated alicyclic hydrocarbon ring structure. Specifically, the alicyclic hydrocarbon ring structure is preferably at least one of a cycloheptane ring structure and a cyclohexane ring structure.

Examples of the aromatic ring structure include a benzene ring structure, a naphthalene ring structure, an anthracene ring structure, and a phenanthrene ring structure. Among these, a benzene ring structure is preferred.

Examples of the heterocyclic structure include a heterocyclic structure containing at least one heteroatom selected from the group consisting of nitrogen, oxygen, and sulfur as atoms constituting the ring. Specifically, a heterocyclic structure containing a nitrogen atom, a heterocyclic structure containing an oxygen atom, a heterocyclic structure containing a sulfur atom, a heterocyclic structure containing an oxygen atom and a nitrogen atom, a heterocyclic structure containing a sulfur atom and a nitrogen atom etc.

Among these, it is preferable that the heterocyclic structure is an isocyanurate ring structure. Since the isocyanurate ring structure has a rigid structure and strong interaction between the rings, it is possible to increase the strength and hardness of the surface layer. Furthermore, since the isocyanurate ring structure does not have an unsaturated bond within the ring, the weather resistance of the surface layer can be improved.

In particular, the cyclic structure is preferably at least one of an alicyclic hydrocarbon ring structure and an isocyanurate ring structure. Since such a cyclic structure is not an aromatic ring structure, the weather resistance of the surface layer can be improved.

Here, the fact that the polymer contained in the surface layer has a first repeating unit containing a cyclic structure can be analyzed by, for example, pyrolysis GC MS and FT IR.

In the first repeating unit, the cyclic structure may be introduced into the main chain or into the side chain.

(i-2) Structure of the first repeating unit The first repeating unit is preferably a repeating unit derived from a first polymerizable compound containing an ionizing radiation-curable functional group and a cyclic structure. Since the polymer contained in the surface layer is a cured product of an ionizing radiation-curable composition, a specific surface shape can be easily formed.

The ionizing radiation-curable functional group is a group that is crosslinked and cured by irradiation with ionizing radiation. For example, a functional group having an ethylenically unsaturated double bond such as a (meth)acryloyl group, a vinyl group, an allyl group, etc. are preferably mentioned.

Note that the (meth)acryloyl group refers to an acryloyl group or a methacryloyl group. Furthermore, (meth)acrylate refers to acrylate or methacrylate.

In addition, ionizing radiation refers to electromagnetic waves or charged particle beams that have energy quantum that can polymerize and/or crosslink molecules, and ultraviolet (UV) or electron beam (EB) are usually used. In addition, electromagnetic waves such as X-rays and γ-rays, and charged particle beams such as α-rays and ion beams are also included.

Examples of the first polymerizable compound include electron beam curable compounds and ultraviolet curable compounds. Among these, ultraviolet curable compounds are preferred. The wrinkle formation stabilizer can stabilize the formation of wrinkles and stably improve the matting effect.

Specifically, the first polymerizable compound can be appropriately selected from among polymerizable monomers and polymerizable oligomers that have been conventionally used as ionizing radiation-curable compounds.

The polymerizable monomer is preferably a (meth)acrylate monomer containing the above-mentioned cyclic structure and having at least a (meth)acryloyl group as an ionizing radiation-curable functional group.
Moreover, it is preferable that the polymerizable monomer containing a cyclic structure is a polyfunctional monomer. Therefore, the polymerizable monomer contains the above-mentioned cyclic structure, has two or more ionizing radiation-curable functional groups in the molecule, and has at least a (meth)acryloyl group as the ionizing radiation-curable functional group. Preference is given to meth)acrylate monomers.

Examples of (meth)acrylate monomers containing a cyclic structure include (meth)acrylate monomers containing a cycloalkane ring, isocyanuric acid (meth)acrylate monomers, and the like.

When the polymerizable monomer containing a cyclic structure is a polyfunctional monomer, the number of functional groups in the polyfunctional monomer is preferably 2 or more and 8 or less, more preferably 2 or more and 6 or less, and even more preferably 2 or more and 4 or less. When the number of functional groups is within the above range, the formation of wrinkles can be stabilized and the matting effect can be stably improved.

Polymerizable monomers containing a cyclic structure can be used alone or in combination.

The polymerizable oligomer is a (meth)acrylate oligomer that includes the above-mentioned cyclic structure, has two or more ionizing radiation-curable functional groups in the molecule, and has at least a (meth)acryloyl group as the ionizing radiation-curable functional group. It is preferable that

Examples of polymerizable oligomers containing a cyclic structure include urethane (meth)acrylate oligomers, epoxy (meth)acrylate oligomers, polyester (meth)acrylate oligomers, polyether (meth)acrylate oligomers, polycarbonate (meth)acrylate oligomers, and acrylic (meth)acrylate oligomers. Examples include meth)acrylate oligomers and isocyanuric acid (meth)acrylate oligomers.

In addition, examples of polymerizable oligomers containing a cyclic structure include highly hydrophobic polybutadiene (meth)acrylate oligomers having (meth)acrylate groups in the side chains of polybutadiene oligomers, and silicone (meth)acrylate oligomers having polysiloxane bonds in the main chain. Examples include acrylate oligomers and aminoplast resin (meth)acrylate oligomers obtained by modifying aminoplast resins having many reactive groups in small molecules. Furthermore, examples of polymerizable oligomers containing a cyclic structure include oligomers having a cationically polymerizable functional group in the molecule, such as novolac-type epoxy resins, bisphenol-type epoxy resins, aliphatic vinyl ethers, and aromatic vinyl ethers.

Among them, urethane (meth)acrylate oligomers containing a cyclic structure, epoxy (meth)acrylate oligomers containing a cyclic structure, polyester (meth)acrylate oligomers containing a cyclic structure, polyether (meth)acrylate oligomers containing a cyclic structure, and polycarbonate (meth)acrylate oligomers containing a cyclic structure. ) Acrylate oligomers, acrylic (meth)acrylate oligomers containing a cyclic structure are preferred. In particular, urethane (meth)acrylate oligomers containing a cyclic structure are preferred. It is possible to stabilize the formation of wrinkles and stably improve the matting effect.

The number of functional groups in the polymerizable oligomer containing a cyclic structure is preferably 2 or more and 10 or less, more preferably 2 or more and 7 or less, and even more preferably 2 or more and 4 or less. When the number of functional groups is within the above range, the formation of wrinkles can be stabilized and the matting effect can be stably improved.

Moreover, the weight average molecular weight of the polymerizable oligomer containing a cyclic structure is preferably 2,500 or more and 7,500 or less, more preferably 3,000 or more and 7,000 or less, and even more preferably 3,500 or more and 6,000 or less. When the weight average molecular weight is within the above range, the formation of wrinkles can be stabilized and the matting effect can be stably improved.

Here, the weight average molecular weight is an average molecular weight measured by GPC analysis and converted to standard polystyrene.

Polymerizable oligomers containing a cyclic structure can be used alone or in combination. Among these, it is preferable to use one type of polymerizable oligomer containing a cyclic structure alone.

The first polymerizable compound may be a polymerizable monomer or a polymerizable oligomer. Among these, the first polymerizable compound is preferably a polymerizable oligomer. When the curable composition used to form the surface layer is solvent-free, the use of a polymerizable monomer containing a cyclic structure increases the viscosity of the curable composition, making it difficult to apply the curable composition. There is a possibility that it will happen. Therefore, when the first polymerizable compound is a polymerizable oligomer containing a cyclic structure, the viscosity of the curable composition can be easily adjusted to be low.

The content ratio of the first repeating unit in the polymer is, for example, 1 mol% or more and 60 mol% or less, and 1.5 mol% or more and 55 mol% or less, based on the total of all repeating units in the polymer. It may be 2 mol% or more and 50 mol% or less. When the content ratio of the first repeating unit is within the above range, the strength and hardness of the surface layer can be improved.

Note that the content ratio of the first repeating unit in the polymer can be determined from the charging ratio of the raw materials.

(ii) Second repeating unit The second repeating unit constituting the polymer contained in the surface layer contains a polyoxyalkylene group.

(ii-1) Polyoxyalkylene group Examples of polyoxyalkylene groups include polyoxyalkylene groups in which the oxyalkylene group constituting the polyoxyalkylene group is a linear or branched oxyalkylene group having 2 or more and 20 or less carbon atoms. Examples include oxyalkylene groups. Specific examples include polyoxyethylene group, polyoxypropylene group, polyoxybutylene group, and the like.

Here, the fact that the polymer contained in the surface layer has a second repeating unit containing a polyoxyalkylene group can be analyzed by, for example, pyrolysis GC MS and FT IR.

(ii-2) Structure of second repeating unit The second repeating unit is preferably a repeating unit derived from a second polymerizable compound containing an ionizing radiation-curable functional group and a polyoxyalkylene group. As described above, when the polymer contained in the surface layer is a cured product of an ionizing radiation-curable composition, a specific surface shape can be easily formed.

The ionizing radiation-curable functional group is the same as the ionizing radiation-curable functional group constituting the first polymerizable compound used in the first repeating unit.

Examples of the second polymerizable compound include electron beam curable compounds and ultraviolet curable compounds. Among these, ultraviolet curable compounds are preferred. The wrinkle formation stabilizer can stabilize the formation of wrinkles and stably improve the matting effect.

Specifically, the second polymerizable compound can be appropriately selected from among polymerizable monomers and polymerizable oligomers that have been conventionally used as ionizing radiation-curable compounds.

The polymerizable monomer is preferably a (meth)acrylate monomer containing a polyoxyalkylene group and having at least a (meth)acryloyl group as an ionizing radiation-curable functional group. Further, the polymerizable monomer containing a polyoxyalkylene group is preferably a polyfunctional monomer. Therefore, the polymerizable monomer is a polyfunctional monomer that contains a polyoxyalkylene group, has two or more ionizing radiation-curable functional groups in the molecule, and has at least a (meth)acryloyl group as the ionizing radiation-curable functional group. (Meth)acrylate monomers are preferred.

When the polymerizable monomer containing a polyoxyalkylene group is a polyfunctional monomer, the number of functional groups in the polyfunctional monomer is preferably 2 or more and 8 or less, more preferably 2 or more and 6 or less, and even more preferably 2 or more and 4 or less. When the number of functional groups is within the above range, the formation of wrinkles can be stabilized and the matting effect can be stably improved.

Examples of the polymerizable monomer containing a polyoxyalkylene group include alkylene oxide-modified (meth)acrylate. Examples of alkylene oxide-modified (meth)acrylates include diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, and tripropylene glycol di(meth)acrylate. (meth)acrylate, tetrapropylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, ethoxylated glycerin tri(meth)acrylate, alkoxylated hexanediol diacrylate, alkoxylated neopentyl glycol di(meth)acrylate, Examples include alkoxylated alkyl diacrylates.

Polymerizable monomers containing polyoxyalkylene groups can be used alone or in combination.

The polymerizable oligomer is a (meth)acrylate containing a polyoxyalkylene group, having two or more ionizing radiation-curable functional groups in the molecule, and having at least a (meth)acryloyl group as the ionizing radiation-curable functional group. Preferably, it is an oligomer.

Examples of polymerizable oligomers containing polyoxyalkylene groups include urethane (meth)acrylate oligomers, epoxy (meth)acrylate oligomers, polyester (meth)acrylate oligomers, polyether (meth)acrylate oligomers, polycarbonate (meth)acrylate oligomers, Examples include acrylic (meth)acrylate oligomers.

In addition, examples of polymerizable oligomers containing polyoxyalkylene groups include highly hydrophobic polybutadiene (meth)acrylate oligomers that have (meth)acrylate groups in their side chains, silicones that have polysiloxane bonds in their main chains ( Examples include meth)acrylate oligomers and aminoplast resin (meth)acrylate oligomers obtained by modifying aminoplast resins having many reactive groups in small molecules. Furthermore, examples of polymerizable oligomers containing polyoxyalkylene groups include oligomers having cationically polymerizable functional groups in the molecule, such as novolac-type epoxy resins, bisphenol-type epoxy resins, aliphatic vinyl ethers, and aromatic vinyl ethers. .

Among them, polyoxyalkylene-modified urethane (meth)acrylate oligomer, polyoxyalkylene-modified epoxy (meth)acrylate oligomer, polyoxyalkylene-modified polyester (meth)acrylate oligomer, polyoxyalkylene-modified polyether (meth)acrylate oligomer, polyoxyalkylene Modified polycarbonate (meth)acrylate oligomers and polyoxyalkylene-modified acrylic (meth)acrylate oligomers are preferred. In particular, polyoxyalkylene-modified urethane (meth)acrylate oligomers are preferred. It is possible to stabilize the formation of wrinkles and stably improve the matting effect.

The number of functional groups in the polymerizable oligomer containing a polyoxyalkylene group is preferably 2 or more and 10 or less, more preferably 2 or more and 7 or less, and even more preferably 2 or more and 4 or less. When the number of functional groups is within the above range, the formation of wrinkles can be stabilized and the matting effect can be stably improved.

The weight average molecular weight of the polymerizable oligomer containing a polyoxyalkylene group is preferably 2,500 or more and 7,500 or less, more preferably 3,000 or more and 7,000 or less, and even more preferably 3,500 or more and 6,000 or less. preferable. When the weight average molecular weight is within the above range, the formation of wrinkles can be stabilized and the matting effect can be stably improved.

Polymerizable oligomers containing polyoxyalkylene groups can be used alone or in combination. Among these, it is preferable to use one kind of polymerizable oligomer containing a polyoxyalkylene group.

The second polymerizable compound may be a polymerizable monomer or a polymerizable oligomer.

The content ratio of the second repeating unit in the polymer is, for example, 20 mol% or more and 99 mol% or less, and 25 mol% or more and 97 mol% or less, based on the total of all repeating units in the polymer. It may be 30 mol% or more and 95 mol% or less. If the content of the second repeating unit is within the above range, curing inhibition caused by oxygen can be sufficiently suppressed and the surface hardness of the surface layer can be improved. Furthermore, it is possible to stabilize the formation of wrinkles and improve the matting effect.

Note that the content rate of the second repeating unit in the polymer can be determined from the charging ratio of the raw materials.

(iii) First repeating unit and second repeating unit The first polymerizable compound used in the first repeating unit is a polymerizable oligomer, and the second polymerizable compound used in the second repeating unit is a polymerizable monomer. It is preferable that there be. That is, it is preferable to use a combination of a polymerizable oligomer and a polymerizable monomer. In this case, the polymerizable oligomer that is the first polymerizable compound is preferably a polyfunctional urethane (meth)acrylate oligomer, more preferably a polyfunctional urethane acrylate oligomer. Further, the polymerizable monomer that is the second polymerizable compound is preferably a polyfunctional monomer, more preferably a polyfunctional (meth)acrylate monomer, and even more preferably a polyfunctional acrylate monomer. It is possible to stabilize the formation of wrinkles and stably improve the matting effect. Moreover, the coating properties of the curable composition can be improved.

Moreover, the first repeating unit may further contain a polyoxyalkylene group and may also serve as the second repeating unit.

In this case, the polymer may have a first repeating unit containing a cyclic structure and a polyoxyalkylene group, a first repeating unit containing a cyclic structure and a polyoxyalkylene group, and a first repeating unit containing a polyoxyalkylene group. It may have two repeating units, a first repeating unit containing a cyclic structure and a polyoxyalkylene group, and a first repeating unit containing a cyclic structure and no polyoxyalkylene group. good.

Further, in this case, the first polymerizable compound used for the first repeating unit may be a polymerizable monomer or a polymerizable oligomer, but is preferably a polymerizable oligomer. As described above, when the first polymerizable compound is a polymerizable oligomer containing a cyclic structure, the viscosity of the curable composition can be easily adjusted to be low.

Further, in this case, the content ratio of the first repeating unit in the polymer is, for example, 0.5 mol% or more and 60 mol% or less, and 0.75 mol% or less, based on the total of all repeating units in the polymer. It may be mol% or more and 55 mol% or less, or 1 mol% or more and 50 mol% or less. When the content of the first repeating unit is within the above range, scratch resistance can be improved. Furthermore, it is possible to stabilize the formation of wrinkles and improve the matting effect.

(iv) Other repeating units The polymer contained in the surface layer may have repeating units other than the first repeating unit and the second repeating unit.

The other repeating units are repeating units containing neither a cyclic structure nor a polyoxyalkylene group.

The other repeating units are preferably repeating units derived from a polymerizable compound containing an ionizing radiation-curable functional group. As described above, when the polymer contained in the surface layer is a cured product of an ionizing radiation-curable composition, a specific surface shape can be easily formed.

The ionizing radiation-curable functional group is the same as the ionizing radiation-curable functional group constituting the first polymerizable compound used in the first repeating unit.

Examples of the polymerizable compound include electron beam curable compounds and ultraviolet ray curable compounds.
Among these, ultraviolet curable compounds are preferred. The wrinkle formation stabilizer can stabilize the formation of wrinkles and stably improve the matting effect.

Specifically, the polymerizable compound can be appropriately selected from among polymerizable monomers and polymerizable oligomers that have been conventionally used as ionizing radiation-curable compounds.

The polymerizable monomer is preferably a (meth)acrylate monomer having at least a (meth)acryloyl group as an ionizing radiation-curable functional group. Further, the polymerizable monomer may be a monofunctional monomer or a polyfunctional monomer.

When the polymerizable monomer is a polyfunctional monomer, the number of functional groups of the polyfunctional monomer is preferably 2 or more and 8 or less, more preferably 2 or more and 6 or less, and even more preferably 2 or more and 4 or less. When the number of functional groups is within the above range, the formation of wrinkles can be stabilized and the matting effect can be stably improved.

The polymerizable monomers can be used alone or in combination.

The polymerizable oligomer is preferably a (meth)acrylate oligomer having two or more ionizing radiation-curable functional groups in the molecule and at least a (meth)acryloyl group as the ionizing radiation-curable functional group.

Examples of polymerizable oligomers include urethane (meth)acrylate oligomers, epoxy (meth)acrylate oligomers, polyester (meth)acrylate oligomers, polyether (meth)acrylate oligomers, polycarbonate (meth)acrylate oligomers, and acrylic (meth)acrylate oligomers. etc.

Examples of polymerizable oligomers include highly hydrophobic polybutadiene (meth)acrylate oligomers with (meth)acrylate groups in their side chains, silicone (meth)acrylate oligomers with polysiloxane bonds in their main chains, and small Examples include aminoplast resin (meth)acrylate oligomers obtained by modifying aminoplast resins having many reactive groups in the molecule. Furthermore, examples of the polymerizable oligomer include oligomers having a cationically polymerizable functional group in the molecule, such as novolac-type epoxy resins, bisphenol-type epoxy resins, aliphatic vinyl ethers, and aromatic vinyl ethers.

Among these, urethane (meth)acrylate oligomers, epoxy (meth)acrylate oligomers, polyester (meth)acrylate oligomers, polyether (meth)acrylate oligomers, polycarbonate (meth)acrylate oligomers, and polyacrylic (meth)acrylate oligomers are preferred. In particular, urethane (meth)acrylate oligomers are preferred. It is possible to stabilize the formation of wrinkles and stably improve the matting effect.

The number of functional groups in the polymerizable oligomer is preferably 2 or more and 10 or less, more preferably 2 or more and 7 or less, and even more preferably 2 or more and 4 or less. When the number of functional groups is within the above range, the formation of wrinkles can be stabilized and the matting effect can be stably improved.

Moreover, the weight average molecular weight of the polymerizable oligomer is preferably 2,500 or more and 7,500 or less, more preferably 3,000 or more and 7,000 or less, and even more preferably 3,500 or more and 6,000 or less. When the weight average molecular weight is within the above range, the formation of wrinkles can be stabilized and the matting effect can be stably improved.

Polymerizable oligomers can be used alone or in combination.

The polymerizable compound may be a polymerizable monomer or a polymerizable oligomer, but is preferably a polymerizable monomer.

The content ratio of other repeating units in the polymer is, for example, 40 mol% or less, may be 30 mol% or less, and may be 20 mol% or less, based on the total of all repeating units in the polymer. It may be.

Note that the content ratio of other repeating units in the polymer can be determined from the charging ratio of raw materials.

(b) Other components (i) Wrinkle formation stabilizer The surface layer in the present disclosure may or may not contain a wrinkle formation stabilizer.

When the surface layer contains a wrinkle formation stabilizer, wrinkles can be stably formed on the surface of the surface layer. Although it is possible to form a wrinkle structure on the surface layer without using a wrinkle-forming stabilizer, by using a wrinkle-forming stabilizer, the formed wrinkle structure is stabilized and a stable matte effect, Further, by stably forming wrinkles over the entire surface layer, uniform surface condition can be imparted.

In addition, "wrinkle formation stability" refers to the shape of the wrinkle, the geometrical characteristic values of the wrinkle (length, width, and length-to-width ratio of each protrusion), and the surface properties of the wrinkle (Ra, RSm, This means that the in-plane distribution (dispersion σ) of the wrinkle-forming stabilizer (Spc, etc.) converges by adding the wrinkle-forming stabilizer, compared to the case without the wrinkle-forming stabilizer. As a result, the in-plane distribution (dispersion σ) of the 60° gloss value of the surface layer also converges. The wrinkle formation stabilizer does not diffuse light to suppress light reflection or matte, but is added to stabilize the wrinkle structure.

Therefore, even if the so-called "matting agent" in the prior art and the "wrinkle formation stabilizer" in the present disclosure have the same or similar constituent substances and average particle size, the effects of light reflection suppression and matting on both They differ in the mechanism (action), the structure for suppressing light reflection and producing matteness, and the relationship between the amount used and the degree of surface gloss (gloss value).

In the prior art, matting agents that have been used for suppressing light reflection and matting have their own anti-glare and matting effects due to the light diffusion effect caused by their physical shape.
Specifically, particles generally referred to as matting agents generally have a difference in refractive index between the particles and the surrounding resin and air, and reflect light rays corresponding to the contour shape of the particles and diffuse light through refractive interfaces. Depending on the effect, it produces an anti-glare effect or a matte effect. Therefore, if a matting agent is used in the surface layer, external light (incident light) will be diffused by the matting agent, resulting in a decrease in contrast.

On the other hand, wrinkle-forming stabilizers do not produce anti-glare or matte effects due to light diffusion caused by reflection and refraction of light rays by the particles themselves. By stabilizing the formation, the anti-glare effect and matte effect can be stably imparted to the sheet due to the light diffusion effect at the refractive index difference interface between the surface and air. Therefore, the wrinkle-forming stabilizer used in the present disclosure is different from the matting agent that itself exhibits an anti-glare effect and a matte effect (assuming that the constituent substances and average particle size of both are the same or similar). The mechanisms (actions) of suppressing light reflection and matting, the structures for suppressing light reflection and producing matting, etc. are different between the two.

Furthermore, the "wrinkle formation stabilizer" and the "matting agent" also differ in the relationship between content and surface gloss (gloss value). The same substance A is used as a wrinkle formation initiator AW (W: wrinkle, wrinkle), and when it is contained in a specific amount C to form wrinkles on the surface, the 60° gloss value G of the surface is _60° ^AW (C) is clearly lower than the 60° gloss value G _60° ^AM (C) of the surface when the same substance A is used simply as a matting agent AM and is contained in a specific amount C, but no wrinkles are formed on the surface. That is, the following relational expression holds true.
G _60° ^AW (C)<G _60° ^AM (C)

The wrinkle-forming stabilizer is not a matting agent, but is not particularly limited as long as it has an average particle size of 100% or less of the thickness of the surface layer or 30 μm or less, whichever is smaller. Can be used.

Here, the average particle size of particles such as a wrinkle-forming stabilizer is defined as a cross-section in the thickness direction of the surface layer measured using a scanning electron microscope (SEM) at an accelerating voltage of 3.0 kV and a magnification of 50,000 times. This is the average value (arithmetic mean diameter) of particle diameters measured for non-agglomerated particles of 100 randomly selected particles observed under the following conditions. The particle size was determined by measuring the distance between the two straight lines that maximizes the distance between the two parallel lines when the cross section of the particle is sandwiched between two parallel lines. It is a value.

As the wrinkle formation stabilizer, for example, organic particles or inorganic particles can be used. Organic substances that make up the organic particles include polymethyl methacrylate, acrylic-styrene copolymer resin, melamine resin, polycarbonate, polystyrene, polyvinyl chloride resin, benzoguanamine-melamine-formaldehyde condensate, silicone, fluorine resin, and polyester resin. etc. In order to reduce the difference in refractive index between the resin and the wrinkle-forming stabilizer and reduce the internal haze of the surface layer, it is preferable to use organic particles. Examples of the inorganic substances constituting the inorganic particles include silica, alumina, calcium carbonate, aluminosilicate, and barium sulfate. Among these, silica is preferred because of its excellent transparency. In order to improve the strength of the surface layer, it is preferable to use inorganic particles.

The shape of the wrinkle-forming stabilizer is not particularly limited, and examples thereof include spherical, polyhedral, scaly, amorphous, and the like. Among these, spherical shapes are preferred. This is because the spherical shape suppresses the diffusion of reflected light by the wrinkle-forming stabilizer, making it difficult for contrast to deteriorate.

The surface of the wrinkle-forming stabilizer may be coated with an organic compound to suppress light diffusion.

In addition, for the matting effect, there are two types of wrinkle-forming stabilizers that are distinguished by their average particle size: the average particle size is 100% or less of the surface layer thickness or 30 μm or less, whichever is smaller. It is preferred to use at least one of wrinkle-forming stabilizers. Specifically, the two types of wrinkle forming stabilizers include a first wrinkle forming stabilizer having an average particle size of 1 μm or more and an upper limit of 100% or less of the thickness of the surface layer or 30 μm or less, whichever is smaller; , and a second wrinkle-forming stabilizer having an average particle size of less than 1 μm. By using at least one of the two types of wrinkle-forming stabilizers, the formation of wrinkles is stabilized, and an excellent matting effect can be stably obtained.

The upper limit of the average particle size of the first wrinkle-forming stabilizer is 1 μm or more and 100% or less of the thickness of the surface layer or 30 μm or less, whichever is smaller. In order to stably improve the matting effect, the average particle size of the first wrinkle-forming stabilizer is preferably 1.3 μm or more, more preferably 1.5 μm or more, and still more preferably 1.8 μm or more. In addition, the average particle size of the first wrinkle-forming stabilizer is preferably 90% or less of the surface layer thickness, more preferably 80% or less of the surface layer thickness, More preferably, the thickness is 70% or less of the thickness of the surface layer. Further, the average particle diameter of the first wrinkle formation stabilizer is preferably 20 μm or less, more preferably 10 μm or less, still more preferably 8 μm or less, and even more preferably 7 μm or less in terms of absolute value. The average particle size of the first wrinkle-forming stabilizer may be the smaller of any combination of the upper limit for the thickness of the surface layer and the upper limit for the absolute value. For example, the upper limit may be 90% or less of the thickness of the surface layer and 20 μm or less, whichever is smaller, or the upper limit may be 90% or less of the thickness of the surface layer and 10 μm or less, whichever is smaller. . Note that the thickness of the surface layer will be described later.

Additionally, the average particle size of the second wrinkle-forming stabilizer is less than 1 μm. In order to stabilize the formation of wrinkles and stably improve the matting effect, the average particle size of the second wrinkle formation stabilizer is preferably 1 nm or more, more preferably 3 nm or more, and even more preferably 5 nm or more. . Further, the average particle size of the second wrinkle formation stabilizer is preferably 900 nm or less, more preferably 700 nm or less, and still more preferably 500 nm or less. It is preferable that the average particle size is around visible light or less because the internal haze of the surface layer against visible light is reduced.

The content of the wrinkle-forming stabilizer is preferably 0.5 parts by mass or more, more preferably 0.75 parts by mass or more, still more preferably 1.0 parts by mass or more, even more preferably, based on 100 parts by mass of the polymer. is 1.2 parts by mass or more. When the content of the wrinkle-forming stabilizer is within the above range, the wrinkle-forming stabilizer can stabilize the formation of wrinkles and stably improve the matting effect. The upper limit of the content of the wrinkle-forming stabilizer is not particularly limited, but is preferably 25.0 parts by mass or less, more preferably 15.0 parts by mass or less, even more preferably 10 parts by mass, based on 100 parts by mass of the polymer. 0 parts by weight or less, particularly preferably 7.5 parts by weight or less, and most preferably 6.0 parts by weight or less. When the content of the wrinkle-forming stabilizer is within the above range, the coating properties of the curable composition can be improved and the matting effect can be efficiently improved.

When using the first wrinkle-forming stabilizer and the second wrinkle-forming stabilizer together, the content of each of the first wrinkle-forming stabilizer and the second wrinkle-forming stabilizer is as follows: There is no particular limitation as long as it is within the range. The content of the second wrinkle-forming stabilizer is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and even more preferably 1.0 parts by mass or more, based on 100 parts by mass of the polymer. be. Further, the content of the second wrinkle-forming stabilizer is preferably 10.0 parts by mass or less, more preferably 7.5 parts by mass or less, and even more preferably 5.0 parts by mass, based on 100 parts by mass of the polymer. Particularly preferably 3.5 parts by mass or less. In addition, the blending ratio of the first wrinkle-forming stabilizer and the second wrinkle-forming stabilizer is preferably the blending amount of the first wrinkle-forming stabilizer when the total amount of these is 100 parts by mass. 0.0 parts by mass or more and 0.95 parts by mass or less, more preferably 0.10 parts by mass or more and 0.90 parts by mass, even more preferably 0.20 parts by mass or more and 0.80 parts by mass or less, particularly preferably is 0.30 parts by mass or more and 0.70 parts by mass or less.

As the wrinkle formation stabilizer, organic particles and inorganic particles can be used as described above, but the types of these particles themselves can be said to include those conventionally used as matting agents. In order for the matting agent itself to exhibit anti-glare and matte effects due to the light-diffusing effect caused by its physical shape, it is necessary to use a large amount. However, in the present disclosure, even if the content is small as described above, that is, the content is smaller than the content required to express the matting effect itself due to the light diffusion effect caused by the physical shape. However, a matting effect that is extremely superior to that obtained with a matting agent is obtained. Therefore, even though the sheet of the present disclosure does not substantially contain a matting agent, wrinkles are stably formed on the surface, thereby stably achieving a better matting effect than when a matting agent is used. It can be said that it can be obtained.

(ii) Photopolymerization initiator and photopolymerization accelerator When the polymerizable compound used in each repeating unit constituting the polymer is an ultraviolet curable compound, the curable composition used to form the surface layer is photopolymerizable. It can contain an initiator, a photopolymerization accelerator, and the like.

Examples of the photopolymerization initiator include one or more selected from acetophenone, benzophenone, α-hydroxyalkylphenone, Michler's ketone, benzoin, benzyl dimethyl ketal, benzoyl benzoate, α-acyloxime ester, thioxanthone, and the like.

Further, the photopolymerization accelerator can reduce polymerization inhibition caused by air during curing and can speed up the curing speed. Examples of the photopolymerization accelerator include one or more selected from p-dimethylaminobenzoic acid isoamyl ester, p-dimethylaminobenzoic acid ethyl ester, and the like.

The content of the photopolymerization initiator is preferably 0.1 parts by mass or more, more preferably 0.3 parts by mass or more, and even more preferably 0.5 parts by mass or more, based on 100 parts by mass of the polymer. The content of the photopolymerization initiator is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, even more preferably 1.5 parts by mass or less, particularly preferably 1.5 parts by mass or less, based on 100 parts by mass of the polymer. It is 0 parts by mass or less. When the content of the photopolymerization initiator is within the above range, the effect of efficiently using the photopolymerization initiator can be obtained. Further, the content of the photopolymerization accelerator is the same as that of the photopolymerization initiator described above.

(iii) Weathering agent The surface layer can contain a weathering agent such as an ultraviolet absorber and a light stabilizer. Thereby, weather resistance can be imparted to the surface layer. The ultraviolet absorber is not particularly limited, and examples thereof include benzotriazole ultraviolet absorbers, benzophenone ultraviolet absorbers, triazine ultraviolet absorbers, hydroxyphenyltriazine ultraviolet absorbers, and the like. The light stabilizer is not particularly limited, and examples thereof include hindered amine light stabilizers such as piperidinyl sebacate light stabilizers. Further, the ultraviolet absorber and the light stabilizer may have a reactive functional group having an ethylenic double bond such as a (meth)acryloyl group, vinyl group, or allyl group in the molecule. Weathering agents such as ultraviolet absorbers and light stabilizers can be used alone or in combination.

The content of the ultraviolet absorber is preferably 0.1 parts by mass or more, more preferably 1.0 parts by mass or more, still more preferably 2.0 parts by mass or more, particularly preferably 3 parts by mass, based on 100 parts by mass of the polymer. .0 part by mass or more. Further, the content of the ultraviolet absorber is preferably 10.0 parts by mass or less, more preferably 8.0 parts by mass or less, even more preferably 7.0 parts by mass or less, particularly preferably 100 parts by mass of the polymer. is 6.0 parts by mass or less. When the content of the ultraviolet absorber is within the above range, the effect of efficiently using the ultraviolet absorber can be obtained. Moreover, the content of the light stabilizer is the same as that of the above-mentioned ultraviolet absorber.

(4) Surface layer The thickness of the surface layer is not particularly limited as long as it can form a specific surface shape, but considering ease of formation, etc., it is usually 1 μm or more and preferably is 2 μm or more, more preferably 3 μm or more, even more preferably 4 μm or more, particularly preferably 5 μm or more. Further, the thickness of the surface layer is preferably 300 μm or less, more preferably 200 μm or less, even more preferably 150 μm or less, particularly preferably 100 μm or less. When the thickness of the surface layer is within the above range, the surface shape tends to be a specific surface shape.

Here, the thickness of the surface layer is determined by measuring the thickness at 20 locations on the cross section of the sheet from an image taken using a scanning electron microscope (SEM), and taking the average value of the values at 20 locations. Note that the accelerating voltage of the SEM is 3 kV, and the magnification is set according to the thickness. The same applies to the thicknesses of other layers.

When the sheet according to the present disclosure further includes a base layer as described below, the surface layer may be disposed partially or over the entire surface of the sheet. Among these, it is preferable that the surface layer is disposed over the entire surface of the sheet.

(5) Method for forming the surface layer The method for forming the surface layer consists of a coating layer forming step in which a curable composition is applied to one side of the base material layer to form a coating layer, and a coating layer forming process is performed by irradiation treatment with ionizing radiation. It is preferable to have a surface layer forming step of curing the coating layer to form a surface layer having a specific surface shape.

(i) Coating layer forming step In the coating layer forming step, the curable composition can be applied using known methods such as gravure printing, bar coating, roll coating, reverse roll coating, and comma coating. can be mentioned.

The thickness of the coating layer can be similar to the thickness of the surface layer.

Moreover, when the curable composition contains a solvent, the solvent may be dried after applying the curable composition.

(ii) Surface layer forming step In the surface layer forming step, the coating layer is cured by irradiation treatment with ionizing radiation to form a surface layer having a specific surface shape.

As the irradiation treatment, it is preferable to perform at least the following irradiation treatments (1) and (2) in this order.
(1) Irradiation treatment with a first wavelength light of 100 nm or more and less than 200 nm (2) Irradiation treatment with at least one of an electron beam and a second wavelength light of 200 nm or more and 400 nm or less Irradiation treatment of (1) and (2) above By doing so, the surface shape becomes more likely to become a specific surface shape, and the scratch resistance is more likely to be improved.

The details of the mechanism by which a specific surface shape is more likely to be obtained by performing irradiation using at least the irradiation treatments (1) and (2) above are not known, but it is presumed to be due to the following mechanism.

First, when irradiation treatment with low wavelength (short wavelength) ultraviolet rays as described in (1) above is performed, the energy of the ultraviolet rays penetrates only the surface area and does not reach the lower layers, so that the surface area of the coating layer is Since only the surface begins to harden, it is thought that only the surface undergoes curing shrinkage, forming a wrinkled structure. In this way, the formation of the wrinkled structure is thought to occur when only a certain thickness direction from the surface of the coating layer is cured by irradiation with low wavelength (short wavelength) ultraviolet rays.

Subsequently, by performing irradiation treatment with at least one of the electron beam and high wavelength (long wavelength) ultraviolet rays of 200 nm or more and 400 nm or less as described in (2) above, the wrinkle structure formed on the surface of the coating layer is maintained. , it is possible to promote curing from the near-surface portion where curing progresses slowly to the deep portion separated in the depth direction.

Even with the irradiation treatment in (1) above, the coating layer becomes a cured product over the entire thickness and can become a surface layer, but by further combining the irradiation treatment in (2) above, the cured state is improved. As a result, it is thought that a wrinkle structure appears on the surface of the surface layer, making it easier to obtain a specific surface shape. Furthermore, by becoming a cured product over the entire thickness and improving the cured state, it is thought that the scratch resistance is also improved.

The first wavelength light of 100 nm or more and less than 200 nm employed in the irradiation treatment of (1) above is, for example, a rare gas such as Ar, Kr, Xe, or Ne, or a halogen such as F, Cl, I, or Br. "Excimer light" including light in the ultraviolet wavelength range from an excited state dimer, ie, an excimer, formed by discharge of a gas such as a halide of a rare gas or a mixed gas thereof is preferable. The wavelength of excimer light and the excimer serving as the light source include, for example, light with a wavelength of 126 nm radiated from an Ar ₂ excimer (hereinafter abbreviated as "126 nm (Ar ₂ )"), 146 nm (Kr ₂ ), and 157 nm. (F ₂ ), 172 nm (Xe ₂ ), 193 nm (ArF), or other wavelength light can be preferably employed. As the excimer light, either spontaneous emission light or highly coherent laser light due to stimulated emission can be used, but it is usually sufficient to use spontaneous emission light. Note that a discharge lamp that emits these lights (ultraviolet rays) is also called an "excimer lamp."

Excimer light has a single wavelength peak and is characterized by a narrower wavelength half-width than normal ultraviolet light (for example, ultraviolet light emitted from metal halide lamps, mercury lamps, etc.). By using such excimer light, it becomes easier to develop a wrinkle structure.

For the same reason as above, the wavelength of the first wavelength light is preferably 120 nm or more, more preferably 140 nm or more, still more preferably 150 nm or more, even more preferably 155 nm or more. Further, the wavelength of the first wavelength light is less than 200 nm, particularly preferably 172 nm (Xe ₂ ). In this way, in order to facilitate the appearance of wrinkle structure, it is preferable to use light with a lower wavelength (shorter wavelength), and among the lower wavelength (shorter wavelength) ultraviolet rays (wavelength: 280 nm or less), less than 200 nm of ultraviolet light (wavelength: 280 nm or less) It can also be said that ultraviolet rays with low wavelengths (short wavelengths) in the range of are preferable.

The integrated light amount of the first wavelength light is preferably 1 mJ/cm ² or more, more preferably 2 mJ/cm ² or more, and still more preferably 5 mJ/cm ² or more. Further, the upper limit of the cumulative amount of light of the first wavelength is not particularly limited. Considering productivity such as reducing the number of lights required for irradiation with the first wavelength light and improving production efficiency, the cumulative light amount of the first wavelength light is preferably 1,000 mJ/cm ² or less, or more. It is preferably 300 mJ/cm ² or less, more preferably 100 mJ/cm ² or less, particularly preferably 10 mJ/cm ² or less.

The ultraviolet irradiance is preferably 1 mW/cm ² or more, more preferably 5 mW/cm ² or more, and still more preferably 10 mW/cm ² or more. Further, the ultraviolet irradiance is preferably 10 W/cm ² or less, more preferably 3 W/cm ² or less, and even more preferably 1 W/cm ² or less. In particular, considering productivity, the ultraviolet irradiance is preferably 500 mW/cm ² or less, more preferably 300 mW/cm ² or less, and even more preferably 150 mW/cm ^{2 or} less.

Further, the oxygen concentration when irradiating the first wavelength light is preferably lower, preferably 1,000 ppm or less, more preferably 750 ppm or less, still more preferably 500 ppm or less, particularly preferably 300 ppm or less.

In the surface layer forming step, after the above (1) irradiation treatment with the first wavelength light of 100 nm or more and less than 200 nm, the above (2) irradiation treatment with at least one of the electron beam and the second wavelength light of 200 nm or more and 400 nm or less It is preferable to perform irradiation treatment.

The electron beam irradiation conditions employed in the irradiation treatment (2) above are not particularly limited as long as the curable composition is cured. The acceleration voltage of the electron beam is preferably 10 kV or more, more preferably 30 kV or more, still more preferably 50 kV, even more preferably 75 kV or more.
Further, the accelerating voltage of the electron beam is preferably 300 kV or less, more preferably 250 kV or less, even more preferably 200 kV or less. When the accelerating voltage of the electron beam is within the above range, the cured product is likely to be formed while retaining the shape of the wrinkle structure. Furthermore, scratch resistance is improved.
Moreover, for the same reason as above, the irradiation dose of the electron beam is preferably 5 kGy or more, more preferably 10 kGy or more, and still more preferably 15 kGy or more. Further, the irradiation dose of the electron beam is preferably 150 kGy or less, more preferably 125 kGy or less, and still more preferably 100 kGy or less.

The electron beam source is not particularly limited as long as it can meet the above irradiation conditions, such as Cockroft-Walton type, Vandegraft type, resonant transformer type, insulated core transformer type, linear type, and Dynamitron type. Various electron beam accelerators such as , high frequency type, etc. can be used.

The second wavelength light of 200 nm or more and 400 nm or less employed in the irradiation process in (2) above uses, for example, an ultra-high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc lamp, a black light fluorescent lamp, a metal halide lamp, etc. as a light source. It can be irradiated using an ultraviolet irradiation device. Further, excimer light having a wavelength of 200 nm or more and 400 nm or less, for example, light having a wavelength of 222 nm (KrCl), 247 nm (KrF), or 308 nm (XeCl) may be used.

The wavelength of the second wavelength light employed in the irradiation process (2) above is preferably 330 nm or more and 390 nm or less. When the wavelength of the second wavelength light is within the above range, it becomes easier to maintain the shape of the wrinkle structure as it is. In addition, scratch resistance is also improved. For the same reason as above, the output of the ultraviolet irradiation device is preferably 50 W/cm or more, more preferably 100 W/cm or more. Further, the output of the ultraviolet irradiation device is preferably 300 W/cm or less, more preferably 200 W/cm or less. Further, the irradiation rate is preferably 1 r/min or more, more preferably 3 r/min or more. Further, the irradiation speed is preferably 50 r/min or less, more preferably 10 r/min or less.

Further, (3) irradiation treatment for preliminary curing may be performed before the irradiation treatments (1) and (2) above. By precuring the coating layer as a whole by the irradiation treatment for precuring in (3) above, appropriate viscosity is imparted to the curable composition. Therefore, sagging of the wrinkle structure formed by the irradiation treatment in (1) above is suppressed, and the wrinkle structure can be maintained in a better state.

The wavelength light of the ionizing radiation employed in the irradiation treatment for preliminary curing in (3) above may be, for example, light with a wavelength of more than 320 nm, preferably more than 320 nm and less than 400 nm, more preferably a wavelength of more than 385 nm and less than 400 nm. One example is light (ultraviolet light). In the irradiation treatment (3) above, by using light of the above wavelength (ultraviolet light), the entire coating layer can be precured efficiently.

The ultraviolet irradiance in the irradiation treatment (3) above is preferably 0.01 W/cm ² or more, more preferably 0.1 W/cm ² or more, and still more preferably 0.3 W/cm ² or more. Moreover, the ultraviolet irradiance is preferably 5 W/cm ² or less, more preferably 3 W/cm ² or less, and still more preferably 2 W/cm ² or less. When the ultraviolet ray illuminance is within the above range, the entire coating layer can be precured efficiently without the coating layer being completely cured.

The wavelength light employed in the irradiation process in (3) above is an ultraviolet irradiation device whose light source is, for example, an ultra-high-pressure mercury lamp, a high-pressure mercury lamp, a low-pressure mercury lamp, a carbon arc lamp, a blacklight fluorescent lamp, a metal halide lamp, an LED light, etc. can be used for irradiation.

In the manner described above, a surface layer having a specific surface shape is obtained.

2. Other Layers The sheet in the present disclosure may have layers other than the surface layer. Examples of other layers include a base material layer, a transparent resin layer, a decorative layer, an adhesive layer, a separator layer, and a primer layer. The layer structure of the sheet in the present disclosure can be appropriately designed depending on the application, and may further include other layers having specific functions.

3. Preferred Embodiments Preferred embodiments of the sheet in the present disclosure include a first embodiment in which the entire sheet is transparent, and a second embodiment in which the sheet has a decorative layer. Each aspect will be explained below.

(1) First aspect of the sheet In the sheet of this aspect, the entire sheet is transparent. 3 and 4 are schematic cross-sectional views illustrating the sheet of this embodiment. The sheet 10A shown in FIG. 3 has a surface layer 1 and a base layer 4 in the thickness direction Dt. The sheet 10A shown in FIG. 4 has a surface layer 1, a transparent resin layer 5, a base material layer 4, and an adhesive layer 6 in this order in the thickness direction Dt. In this embodiment, since the entire sheet is transparent, the visibility and design of the adherend are not impaired.

(a) Layer Structure The structure of the sheet of this embodiment other than the surface layer will be described below.

(i) Base layer The sheet of this embodiment may have a base layer on the surface opposite to the surface having the surface shape of the surface layer. The base layer is a member that supports the surface layer. By disposing the surface layer on one surface of the base layer, the surface layer can be easily formed. Further, since the sheet has a base material, various performances such as mechanical strength and suitability for post-processing are improved, so that usability as a sheet is improved.

In this embodiment, the base layer is transparent. The base material layer may be transparent enough to allow the adherend to be visually recognized, and may be colorless and transparent, colored transparent, or semitransparent. That is, in this specification, "transparent" means not only colorless and transparent but also colored transparent and translucent.

The total light transmittance of the base material layer is preferably 90% or more, and more preferably 92% or more, for example.

Here, the total light transmittance of the base material layer can be measured in accordance with JIS K7361-1.

As the base material layer, a transparent resin base material or a glass base material can be used. The type of base material layer is appropriately selected depending on the use of the sheet.

The resin constituting the transparent resin base material is not particularly limited, and includes, for example, olefin resins such as polyethylene, polypropylene, polymethylpentene, ionomers, and various olefin thermoplastic elastomers; polyvinyl chloride, polyvinylidene chloride, and vinyl chloride. Vinyl chloride resins such as vinyl acetate copolymers; polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, ethylene glycol-terephthalic acid-isophthalic acid copolymers, polyester thermoplastic elastomers; poly(meth)acrylic acid Acrylic resins such as methyl, ethyl poly(meth)acrylate, butyl poly(meth)acrylate, methyl(meth)acrylate-butyl(meth)acrylate copolymer; polyamides represented by nylon 6, nylon 66, etc. Resin; Cellulose resin such as cellulose triacetate, cellophane, celluloid; Styrene resin such as polystyrene, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-styrene copolymer (ABS resin); Polyvinyl alcohol, ethylene-vinyl acetate copolymer , ethylene-vinyl alcohol copolymer, polycarbonate resin, polyarylate resin, polyimide resin and the like. These resins are appropriately selected depending on the use of the sheet and the like.

The base material layer may contain additives as necessary. Examples of additives include flame retardants, lubricants, foaming agents, antioxidants, ultraviolet absorbers, and light stabilizers. The content of the additive is not particularly limited as long as it does not impede the surface properties, processing properties, etc., and can be appropriately set according to the required properties. Among these, from the viewpoint of improving the weather resistance of the sheet, it is preferable to use weathering agents such as ultraviolet absorbers and light stabilizers. The ultraviolet absorber and light stabilizer are the same as those used in the surface layer.

The base material layer may be a single layer or a laminate of two or more layers.

The thickness of the base material layer is not particularly limited, but for example, it is preferably 10 μm or more and 300 μm or less, more preferably 20 μm or more and 200 μm or less, and even more preferably 40 μm or more and 100 μm or less.

The base material layer is surface-treated to improve adhesion with layers in contact with the base material layer, such as adhesion with the surface layer, adhesion with the transparent resin layer, and adhesion with the adhesive layer. It's okay. Examples of the surface treatment include physical surface treatments such as oxidation methods and roughening methods, and chemical surface treatments. Examples of the oxidation method include corona discharge treatment, chromium oxidation treatment, flame treatment, hot air treatment, and ozone-ultraviolet treatment. Examples of the roughening method include a sandblasting method, a solvent treatment method, and the like. These surface treatments are appropriately selected depending on the type of the base material layer, but corona discharge treatment is generally preferred in consideration of the effects and operability of the surface treatment.

(ii) Transparent resin layer The sheet of this embodiment may have a transparent resin layer between the surface layer and the base layer. The transparent resin layer can increase the strength of the sheet.

The transparent resin layer may be transparent enough to allow the adherend to be visually recognized, and may be colorless and transparent, colored transparent, or semitransparent.

Examples of the resin constituting the transparent resin layer include polyolefin resin, polyester resin, polycarbonate resin, acrylonitrile-butadiene-styrene resin (hereinafter also referred to as "ABS resin"), acrylic resin, vinyl chloride resin, etc. It will be done. In consideration of processing suitability, polyolefin resins and vinyl chloride resins are particularly preferred. The resin may be used alone or in combination of two or more.

The transparent resin layer may contain additives as necessary. Examples of additives include weathering agents such as ultraviolet absorbers and light stabilizers. The weathering agent may be appropriately selected from those listed above.

Considering processability and the like, the thickness of the transparent resin layer is preferably 20 μm or more and 150 μm or less, more preferably 40 μm or more and 120 μm or less, and even more preferably 60 μm or more and 100 μm or less.

Examples of methods for forming the transparent resin layer include a method of applying a resin composition and a method of laminating resin films by dry lamination or the like.

(iii) Adhesive layer The sheet of this embodiment may have an adhesive layer on the side opposite to the surface layer of the base layer. The adhesive layer is a member for attaching the sheet to an adherend.

In this embodiment, the adhesive layer is transparent. The adhesive layer may be transparent enough to allow the adherend to be visually recognized, and may be colorless and transparent, colored transparent, or semitransparent.

Examples of adhesives used in the adhesive layer include curable adhesives and pressure-sensitive adhesives. Specific examples include urethane adhesives, acrylic adhesives, epoxy adhesives, rubber adhesives, and the like. Moreover, OCA (Optically Clear Adhesive), OCR (Optically Clear Resin), or the like can also be used as the adhesive layer.

The thickness of the adhesive layer is preferably 5 μm or more and 100 μm or less, more preferably 10 μm or more and 75 μm or less, and even more preferably 20 μm or more and 50 μm or less, from the viewpoint of efficiently obtaining the desired adhesive force.

Examples of methods for forming the adhesive layer include a method of applying an adhesive composition and a method of laminating adhesive films by dry lamination or the like.

(iv) Primer layer The sheet of this embodiment may have a primer layer in order to improve the interlayer adhesion of the plurality of layers constituting the sheet. For example, if the sheet has a base layer, the primer layer may be disposed between the surface layer and the base layer. Furthermore, when the sheet has a transparent resin layer, the primer layer may be disposed between the transparent resin layer and the surface layer.

The primer layer is mainly composed of a binder resin, and may contain additives such as an ultraviolet absorber and a light stabilizer, if necessary.

Binder resins include urethane resins, acrylic polyol resins, acrylic resins, ester resins, amide resins, butyral resins, styrene resins, urethane-acrylic copolymers, and polycarbonate-based urethane-acrylic copolymers (with carbonate bonds in the polymer main chain). urethane-acrylic copolymer derived from a polymer (polycarbonate polyol) having two or more hydroxyl groups at the terminal or side chain), vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate-acrylic copolymer Examples include coalescing resin, chlorinated propylene resin, nitrocellulose resin (nitrified cotton), and cellulose acetate resin. These can be used alone or in combination.

The binder resin may also be a resin that is crosslinked and cured by adding a curing agent such as an isocyanate curing agent or an epoxy curing agent to the above resin. For example, a resin in which a polyol resin such as an acrylic polyol resin is crosslinked and cured with an isocyanate curing agent is preferable, and a resin in which an acrylic polyol resin is crosslinked and cured in an isocyanate curing agent is more preferable.

The thickness of the primer layer is preferably 0.5 μm or more, more preferably 1 μm or more, and still more preferably 2 μm or more. Further, the thickness of the primer layer is preferably 10 μm or less, more preferably 8 μm or less, and still more preferably 6 μm or less.

Examples of the method for forming the primer layer include a method in which a resin composition is applied, and if necessary, dried and cured.

(v) Separator layer The sheet of this embodiment may have a separator layer on the surface of the adhesive layer opposite to the base layer. The separator layer is a member that protects the adhesive layer, and is peeled off when the sheet is attached to an adherend. As the separator layer, conventionally known ones can be used.

(b) Physical properties of sheet The sheet of this embodiment is transparent. Specifically, the total light transmittance of the sheet is preferably 85% or more, more preferably 88% or more, and even more preferably 90% or more. By having such a high total light transmittance, a sheet with good transparency can be obtained.

Note that the total light transmittance of the sheet is the total light transmittance of the sheet excluding the separator layer when the sheet has a separator layer.

Here, the total light transmittance of the sheet can be measured in accordance with JIS K7361-1.

(c) Applications The sheet of this embodiment can be used, for example, as an anti-glare film, a protective film, an overlay film, various functional films, and the like.

(2) Second aspect The sheet of this aspect has a decorative layer. 5 and 6 are schematic cross-sectional views illustrating the sheet of this embodiment. The sheet 10B shown in FIG. 5 has a surface layer 1, a transparent resin layer 5, a decorative layer 7, a base material layer 4, an adhesive layer 6, and a separator layer 8 in this order in the thickness direction Dt. The sheet 10B shown in FIG. 6 has a surface layer 1 and a base layer 4 in the thickness direction Dt, and the base layer 4 also serves as the decorative layer 7.

(a) Layer Structure The structure of the sheet of this embodiment other than the surface layer will be described below.

(i) Base layer The sheet of this embodiment may have a base layer on the surface opposite to the surface having the surface shape of the surface layer. The base layer is a member that supports the surface layer. By disposing the surface layer on one surface of the base layer, the surface layer can be easily formed. Further, since the sheet has a base material layer, various performances such as mechanical strength, suitability for post-processing, designability, etc. are improved, and therefore usability as a sheet is improved.

The base material layer is not particularly limited, and examples thereof include a resin base material, a glass base material, a metal base material, a fiber base material, and the like. The type of base material layer is appropriately selected depending on the use of the sheet.

Examples of the resin used for the resin base material include various synthetic resins and natural resins. Examples of synthetic resins include thermoplastic resins and curable resins. Thermoplastic resins are preferred in consideration of sheet manufacturing suitability, handling suitability, post-processing suitability, and the like.

Examples of thermoplastic resins include olefin resins such as polyethylene, polypropylene, polymethylpentene, ionomers, and various olefin thermoplastic elastomers; vinyl chloride resins such as polyvinyl chloride, polyvinylidene chloride, and vinyl chloride-vinyl acetate copolymers; polyethylene Polyester resins such as terephthalate, polybutylene terephthalate, polyethylene naphthalate, ethylene glycol-terephthalic acid-isophthalic acid copolymer, polyester thermoplastic elastomer; polymethyl poly(meth)acrylate, poly(meth)ethyl acrylate, poly( Acrylic resins such as butyl meth)acrylate and methyl (meth)acrylate-butyl (meth)acrylate copolymers; Polyamide resins such as nylon 6 and nylon 66; Celluloses such as cellulose triacetate, cellophane, and celluloid. Resin; Styrene resin such as polystyrene, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-styrene copolymer (ABS resin); polyvinyl alcohol, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, polycarbonate resin, Examples include polyarylate resin and polyimide resin.

Examples of natural resins include natural rubber, pine resin, amber, and the like.

Furthermore, examples of the curable resin include ionizing radiation curable resins and thermosetting resins.

Examples of metals used for the metal base material include aluminum or aluminum alloys such as duralumin; iron or iron alloys such as carbon steel and stainless steel; copper or copper alloys such as brass and bronze; gold, silver, chromium, nickel, Examples include cobalt, tin, and titanium. The metal base material may have a plating film or an anodized film on the surface.

Examples of fibrous materials used for the fiber base material include tissue paper, kraft paper, high-quality paper, Japanese paper, titanium paper, linter paper, parchment paper, paraffin paper, parchment paper, glassine paper, backing paper for wallpaper, paperboard, and plaster. Paper such as base paper for boards; woven fabrics or non-woven fabrics made of fibers such as polyester resin fibers, acrylic resin fibers, protein or cellulose natural fibers such as silk, cotton, and hemp, glass fibers, and carbon fibers; Various resins such as acrylic resin, styrene-butadiene rubber, melamine resin, and urethane resin may be added to the fiber base material. When the fiber base material is a paper base material, the strength between fibers of the paper base material or the interlayer strength between the paper base material and another base material can be improved. Moreover, fluffing can be suppressed. As a method for adding the resin, the resin may be impregnated after papermaking, or the resin may be filled inside the paper during papermaking. Examples of the paper base material to which resin is added include interpaper reinforced paper, resin-impregnated paper, and the like.

In the case of a fiber base material, it is preferable that a permeation-preventing resin layer is disposed on the surface layer side of the fiber base material. Examples of the resin used for the penetration prevention resin layer include two-component curable urethane resin. The transmission prevention layer resin layer can be formed by a method such as coating.

The base material layer may contain additives as necessary. In the case of a resin base material, examples of additives include inorganic fillers, flame retardants, lubricants, foaming agents, antioxidants, ultraviolet absorbers, light stabilizers, and colorants. Various additives can be used alone or in combination. The content of the additive is not particularly limited as long as it does not impede the surface properties, processing properties, etc., and can be appropriately set according to the required properties.

Among the above additives, it is preferable to use weathering agents such as ultraviolet absorbers and light stabilizers in order to improve weather resistance. The ultraviolet absorber and light stabilizer may be the same as those used in the surface layer.

The base material layer may be a single layer or a laminate of two or more layers. In the case of a laminate, the base material layer may have two or more layers of the same type of base material, or may have two or more layers of different types of base materials.

In this embodiment, the base material layer can also serve as a decorative layer, which will be described later.

The base layer may be transparent or opaque. If the base layer is opaque, the base layer can be a decorative layer.

Moreover, the base material layer may be colored. When the base layer is colored, the base layer can be a decorative layer. The mode of coloring is not particularly limited, and may be transparent coloring or opaque coloring (hidden coloring), and these can be arbitrarily selected.

When the base material layer is colored, it can contain a coloring agent. Examples of colorants include white pigments such as titanium white; inorganic pigments such as iron black, yellow lead, titanium yellow, Bengara, cadmium red, ultramarine blue, and cobalt blue; quinacridone red, isoindolinone yellow, phthalocyanine blue, and nickel. - Organic pigments or dyes such as azo complexes, azomethine azo black pigments, and perylene black pigments; Metallic pigments made from flaky foil pieces such as aluminum and brass; Made from scaly foil pieces such as titanium dioxide-coated mica and basic lead carbonate. Examples include pearlescent pigments. For example, if the surface hue of the adherend on which the sheets are laminated varies and it is desired to hide the surface hue and improve the stability of the color tone of the decorative layer, an inorganic pigment such as a white pigment may be used.

The base layer may be surface-treated to improve adhesion with layers in contact with the base layer, such as adhesion with the decorative layer and adhesion with the adhesive layer. The surface treatment is the same as that for the base layer in the sheet of the first embodiment.

Moreover, when the base material layer is a laminate, an adhesive layer or a primer layer may be arranged between each layer in order to improve the adhesiveness of each adjacent layer.

The thickness of the base layer is not particularly limited, and is appropriately selected depending on the material of the base layer. In the case of a base material layer containing a resin, the thickness of the base material layer is, for example, preferably 10 μm or more and 300 μm or less, more preferably 20 μm or more and 200 μm or less, and further preferably 40 μm or more and 100 μm or less. preferable. Further, when the base material layer is a paper base material, the basis weight is usually preferably 20 g/m ² or more and 150 g/m ² or less, more preferably 30 g/m ² or more and 100 g/m ² or less.

(ii) Decorative layer The sheet of this embodiment has a decorative layer on the side opposite to the surface having the specific surface shape of the surface layer. The decorative layer allows a design to be added to the sheet. The decoration layer may be placed on the side of the surface layer opposite to the surface having a specific surface shape; for example, the decoration layer may be placed between the base layer and the surface layer, Further, as described later, when the sheet has a transparent resin layer, the decorative layer may be disposed between the base layer and the transparent resin layer.

The decorative layer may be, for example, a colored layer, a pattern layer, or a metal layer. Further, the decorative layer may include a colored layer and a pattern layer.

The colored layer may be a so-called solid colored layer disposed over the entire surface of the sheet. The colored layer can contain a binder resin and a colorant. The colored layer can be formed by a coating method.

The pattern of the pattern layer is not particularly limited, and includes, for example, wood grain patterns such as annual rings and conduit grooves on the surface of a wooden board; stone grain patterns on the surface of a stone board such as marble and granite; cloth grain patterns on the surface of a fabric; and leather surfaces. Examples include leather texture patterns; geometric patterns; letters; figures; combinations of these.

The pattern layer can contain a binder resin and a colorant. The pattern layer can be formed by a printing method.

The binder resin used for the colored layer and pattern layer is not particularly limited, and examples thereof include urethane resin, acrylic polyol resin, acrylic resin, ester resin, amide resin, butyral resin, styrene resin, urethane-acrylic copolymer, and chloride resin. Examples include resins such as vinyl-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate-acrylic copolymer resin, chlorinated propylene resin, nitrocellulose resin, and cellulose acetate resin. Moreover, various resins can be used, such as a one-component curable resin and a two-component curable resin with a curing agent such as an isocyanate compound.

Coloring agents used in the colored layer and pattern layer include pigments and dyes. Among these, the colorant is preferably a pigment that has excellent hiding properties and weather resistance. The pigment can be the same as the pigment used in the base layer. The content of the colorant is preferably 5 parts by mass or more and 90 parts by mass or less, more preferably 15 parts by mass or more and 80 parts by mass or less, and 30 parts by mass or more and 70 parts by mass or less, based on 100 parts by mass of the binder resin. It is more preferably less than parts by mass.

The colored layer and the pattern layer may contain additives such as ultraviolet absorbers, weathering agents such as light stabilizers, extender pigments, stabilizers, plasticizers, curing agents, catalysts, etc., as necessary.

Examples of the metal material used for the metal layer include aluminum, chromium, tin, and indium. The metal layer can be formed by a vapor deposition method.

The thickness of the decorative layer is appropriately selected depending on the desired design and the type of the decorative layer. When the decorative layer has at least one of a colored layer and a pattern layer, the thickness of the decorative layer is, for example, 0.5 μm or more, in order to hide the ground color of the adherend and improve the design. It is preferably 20 μm or less, more preferably 1 μm or more and 10 μm or less, and even more preferably 2 μm or more and 5 μm or less.

(iii) Transparent resin layer The sheet of this embodiment may have a transparent resin layer between the surface layer and the decorative layer. The transparent resin layer can increase the strength of the sheet and protect the decorative layer.

The transparent resin layer may be transparent enough to allow the decoration layer to be visually recognized, and may be colorless and transparent, colored transparent, or semitransparent.

Since the transparent resin layer is the same as the transparent resin layer in the sheet of the first aspect, a description thereof will be omitted here.

(iv) Adhesive layer The sheet of this embodiment may have an adhesive layer on the side of the base material layer opposite to the decorative layer. The adhesive layer is a member for attaching the sheet to an adherend.

The adhesive layer may be transparent or opaque.

The adhesive used for the adhesive layer and the thickness of the adhesive layer are the same as those for the adhesive layer in the sheet of the first embodiment.

(v) Primer layer The sheet of this embodiment may have a primer layer in order to improve the interlayer adhesion of the plurality of layers constituting the sheet. The primer layer is the same as the primer layer in the sheet of the first aspect.

(vi) Separator layer The sheet of this embodiment may have a separator layer on the surface of the adhesive layer opposite to the base layer. The separator layer is a member that protects the adhesive layer, and is peeled off when the sheet is attached to an adherend. The separator layer is the same as the separator layer in the sheet of the first aspect.

(b) Applications The sheet of this embodiment can be used, for example, as a decorative sheet, a decorative sheet, artificial leather, and the like.

B. Article The article in this disclosure has two embodiments. Each embodiment will be explained separately below.

I. First Embodiment of Article The article of this embodiment has the above-mentioned sheet on its surface. In the article, the sheet is placed such that the surface of the surface layer having the surface shape faces the viewer.

FIG. 7(a) is a schematic cross-sectional view illustrating the article of this embodiment, and is an example in which the article has the sheet of the above-described first aspect. The article 100A shown in FIG. 7(a) has a sheet 10A of the first aspect on its surface. In the article 100A, the sheet 10A is bonded to the article body 20 via the adhesive layer 6 of the sheet 10A.

When the article of this embodiment has the sheet of the first aspect, the sheet of the first aspect is transparent, so that the main body of the article can be visually recognized.

FIG. 7(b) is a schematic cross-sectional view illustrating the article of this embodiment, and is an example in which the article includes the sheet of the above-mentioned second aspect. The article 100B shown in FIG. 7(b) has a sheet 10A of the second aspect on its surface. In the article 100B, the sheet 10B is bonded to the article body 20 via the adhesive layer 14 of the sheet 10B.

When the article of this embodiment has the sheet of the second aspect, the sheet of the second aspect has a decorative layer, so that designability can be imparted.

Each structure of the article of this embodiment will be explained below.

1. Sheet The sheet in the present disclosure is placed on the surface of the article. The sheet is arranged such that the surface having the surface shape of the surface layer faces the viewer.

The sheet is the same as described in "A. Sheet" above, so a description thereof will be omitted here.

2. Article The article of this embodiment may be used outdoors or indoors.

When the sheet is the sheet of the first aspect, the article may be a visual object intended to be viewed, or an article placed between the observer and the visual object. preferable. Items that are visual objects include, for example, display devices such as liquid crystal display devices, organic EL display devices, and LED display devices; signs such as road signs and construction signs; signboards; painted members; decorative members; and vehicle instrument panels. ;Clock; etc. Here, the painted member means painted building materials, furniture, and the like. Moreover, the decorative member means a building material, furniture, etc. decorated with a decorative sheet. Further, examples of articles placed between the observer and the visual object include a showcase, a show window, a window, and the like.

Also, when the sheet is a sheet of the second aspect, the article generally has a decorative surface. Such items include, for example, interior parts of buildings such as walls, ceilings, and floors; exterior parts such as exterior walls, roofs, soffits, fences, and gates; window frames, doors, handrails, baseboards, and surroundings. Fittings or fixtures such as edges and moldings; General furniture such as chests of drawers, shelves, and desks; Kitchen furniture such as dining tables and sinks; Various furniture and parts used in plumbing areas such as kitchens, toilets, bathrooms, and sinks; Home appliances , surface decorative boards for cabinets of OA equipment, etc.; interior or exterior members for vehicles; and the like.

In the article, the surface on which the sheet is placed may be, for example, a flat surface, a curved surface, or an uneven surface.

II. Second Embodiment of Article The article of this embodiment is an article having a surface layer on the surface, the surface of the surface layer on the observer side has a surface shape having a wrinkle structure, and the surface shape conforms to the JIS standard of the surface shape. RSm (average length of curved elements) defined in B0601:2013 is 50 μm or less, and the surface layer has a first repeating unit containing a cyclic structure and a second repeating unit containing a polyoxyalkylene group. Contains a polymer with

FIG. 8 is a schematic cross-sectional view showing an example of the article of this embodiment. The article 100C shown in FIG. 8 has a surface layer 1 on its surface, and a surface S1 of the surface layer 1 on the observer side has a surface shape having a wrinkled structure. In the article 100C, the surface layer 1 is placed directly on the surface of the article body 20.

Each structure of the article of this embodiment will be explained below.

1. Surface Layer The surface layer in this embodiment is the same as that described in "A. Sheet 1. Surface layer" above, so the description here will be omitted.

2. Article The article of this embodiment is the same as the article of the first embodiment, so a description thereof will be omitted here.

C. Decorative Sheet The decorative sheet in the present disclosure includes the sheet described above.

Since the decorative sheet according to the present disclosure includes the above-described sheet, it is possible to achieve both matte properties and scratch resistance.

Since the structure of the decorative sheet is the same as that described in "A. Sheet 3. Preferred Embodiment (2) Second Embodiment of Sheet" above, the explanation here will be omitted.

D. Decorative Material The decorative material in the present disclosure includes an adherend and the above-mentioned decorative sheet disposed on one surface of the adherend. In the decorative material, the decorative sheet is arranged such that the surface of the surface layer having the surface shape faces the viewer.

Since the contents of the decorative sheet are the same as those described in "C. Decorative Sheet" above, the explanation here will be omitted.

Examples of the adherend include plate materials such as flat plates and curved plates made of various materials, three-dimensional articles such as cylinders and polygonal columns, sheets, and the like. For example, it can be used as board materials such as wood veneers made of various woods such as cedar, cypress, pine, and lauan, wood plywood, laminated wood, particle boards, and wood fiberboards such as MDF (medium density fiberboard), and three-dimensional shaped articles. Wooden components used as plates, three-dimensional articles, or sheets made of metals such as iron, aluminum, copper, and alloys containing one or more of these metals; Ceramics such as glass and china, plaster, and cement , ALC (lightweight aerated concrete), calcium silicate, and other non-ceramic ceramic materials used as plates and three-dimensional shaped articles; -butadiene-styrene copolymer) resin, phenol resin, vinyl chloride resin, cellulose resin, rubber, and other resin members used as plates, three-dimensional articles, sheets, etc.
Further, these members can be used alone or in combination.

In addition, adherend materials specifically include interior parts of buildings such as walls, ceilings, and floors; exterior parts such as outer walls, roofs, soffits, fences, and gates; window frames, doors, handrails, widths, etc. Fittings or fixtures such as wood, surrounds, and moldings; General furniture such as chests of drawers, shelves, and desks; Kitchen furniture such as dining tables and sinks; Various furniture used in plumbing areas such as kitchens, toilets, bathrooms, washstands, etc. Members; surface decorative boards for cabinets such as home appliances and OA equipment; members for interior or exterior of vehicles; and the like.

The decorative material in the present disclosure may be used outdoors or indoors.

E. Curable Composition The curable composition in the present disclosure is a curable composition used for a surface layer having a surface shape having a wrinkled structure, which comprises a first polymerizable compound containing a cyclic structure and a polyoxyalkylene group. and a second polymerizable compound containing the second polymerizable compound.

According to the curable composition of the present disclosure, as described in "A. Sheet" above, it is possible to achieve both matte properties and scratch resistance.

Each structure of the curable composition in the present disclosure will be described below.

1. First Polymerizable Compound The first polymerizable compound includes a cyclic structure.

The first polymerizable compound is the same as that described in "A. Decorative sheet 1. Surface layer (3) Surface layer material (a) Polymer (i) First repeating unit", so here The explanation will be omitted.

The content of the first polymerizable compound is, for example, 5% by mass or more and 60% by mass or less, and may be 10% by mass or more and 55% by mass or less, and 15% by mass or less, based on the solid content of the curable composition. % or more and 50% by mass or less.

Moreover, the first polymerizable compound may further contain a polyoxyalkylene group and serve as the second polymerizable compound.

In this case, the curable composition may contain a first polymerizable compound containing a cyclic structure and a polyoxyalkylene group, and a first polymerizable compound containing a cyclic structure and a polyoxyalkylene group; a first polymerizable compound that contains a cyclic structure and a polyoxyalkylene group; and a first polymerizable compound that contains a cyclic structure and does not contain a polyoxyalkylene group. It may contain.

When the first polymerizable compound also serves as the second polymerizable compound, the content of the first polymerizable compound is, for example, 10% by mass or more and 80% by mass or less based on the solid content of the curable composition, and 15 The content may be from 20% by mass to 75% by mass, and from 20% by mass to 70% by mass.

2. Second Polymerizable Compound The second polymerizable compound contains a polyoxyalkylene group.

The second polymerizable compound is the same as that described in "A. Decorative sheet 1. Surface layer (3) Surface layer material (a) Polymer (ii) Second repeating unit", so here The explanation will be omitted.

The content of the second polymerizable compound is, for example, 30% by mass or more and 90% by mass or less, may be 35% by mass or more and 85% by mass or less, and 40% by mass or less, based on the solid content of the curable composition. % or more and 80% by mass or less.

3. Other Polymerizable Compounds The curable composition in the present disclosure may contain other polymerizable compounds other than the first polymerizable compound and the polymerizable compound. Other polymerizable compounds are the same as those described in "A. Decorative sheet 1. Surface layer (3) Surface layer material (a) Polymer (iv) Other repeating units", so here The explanation will be omitted.

The content of the other polymerizable compound is, for example, 30% by mass or less, may be 25% by mass or less, or may be 20% by mass or less based on the solid content of the curable composition.

4. Other Components The curable compositions of the present disclosure may or may not contain wrinkle-forming stabilizers. The wrinkle formation stabilizer is the same as that described in "A. Decorative sheet 1. Surface layer (3) Surface layer material (b) Other components" above, so the explanation here will be omitted.

Further, when the first polymerizable compound and the second polymerizable compound are ultraviolet curable compounds, the curable composition in the present disclosure can contain a photopolymerization initiator and a photopolymerization accelerator. The photopolymerization initiator and photopolymerization accelerator are the same as those described in "A. Decorative sheet 1. Surface layer (3) Surface layer material (b) Other components", so they are used here. Explanation will be omitted.

The curable composition in the present disclosure can include a weathering agent such as a UV absorber and a light stabilizer. The weathering agent is the same as that described in "A. Decorative sheet 1. Surface layer (3) Surface layer material (b) Other components", so the explanation here will be omitted.

The curable composition in the present disclosure may or may not contain a solvent. Among these, the curable composition is preferably solvent-free.

The present disclosure is not limited to the above embodiments. The above-mentioned embodiments are illustrative, and any configuration that has substantially the same technical idea as the technical idea stated in the claims of the present disclosure and has similar effects is disclosed in the present disclosure. covered within the technical scope of

[Synthesis example 1]
60.7 parts by mass of polyisocyanate containing an isocyanurate ring derived from hexamethylene diisocyanate (manufactured by Tosoh Corporation, Coronate HXLV), 39.2 parts by mass of 2-hydroxyethyl acrylate, and 0.06 parts by mass of p-methoxyphenol. and 0.32 parts by mass of dibutylhydroxytoluene were mixed and heated to 60°C. After the internal temperature stabilized at 60° C., 0.06 parts by mass of zirconium tetraacetylacetonate was added. After the heat generated by zirconium tetraacetylacetonate stabilized, the temperature was maintained at 90° C. and the reaction was carried out for 4 hours to synthesize a urethane acrylate oligomer containing an isocyanurate ring. Thereafter, the isocyanate group content of the urethane acrylate oligomer was determined by the method specified in JIS K7301, and it was confirmed that the isocyanate group content was 0.1% or less. Thereby, urethane acrylate oligomer 1 was obtained.

[Synthesis example 2]
The cyclohexane ring was prepared in the same manner as in Synthesis Example 1, except that the polyisocyanate was changed to 53.1 parts by mass of dicyclohexylmethane diisocyanate and the amount of 2-hydroxyethyl acrylate was changed to 46.9 parts by mass. We synthesized urethane acrylate oligomers containing Thereafter, in the same procedure as in Synthesis Example 1, it was confirmed that the isocyanate group content was 0.1% or less. Thereby, urethane acrylate oligomer 2 was obtained.

[Synthesis example 3]
In Synthesis Example 1, the amount of polyisocyanate was changed to 39.9 parts by mass, and 2-hydroxyethyl acrylate was changed to 60.1 parts by mass of ethylene oxide-modified 2-hydroxyethyl acrylate (manufactured by NOF Corporation, Bremmer AE-200). An ethylene oxide-modified urethane acrylate oligomer containing an isocyanurate ring was synthesized in the same manner as in Synthesis Example 1 except for the following changes. Thereafter, in the same procedure as in Synthesis Example 1, it was confirmed that the isocyanate group content was 0.1% or less. Thereby, urethane acrylate oligomer 3 was obtained.

[Synthesis example 4]
Urethane acrylate was prepared in the same manner as in Synthesis Example 1, except that the polyisocyanate was changed to 58.1 parts by mass of hexamethylene diisocyanate and the amount of 2-hydroxyethyl acrylate was changed to 41.9 parts by mass. Oligomers were synthesized. Thereafter, in the same procedure as in Synthesis Example 1, it was confirmed that the isocyanate group content was 0.1% or less. Thereby, urethane acrylate oligomer 4 was obtained.

[Synthesis example 5]
In Synthesis Example 1, the benzene ring was produced in the same manner as in Synthesis Example 1, except that the polyisocyanate was changed to 44.8 parts by mass of xylene diisocyanate and the amount of 2-hydroxyethyl acrylate was changed to 55.2 parts by mass. We synthesized urethane acrylate oligomers containing Thereafter, in the same procedure as in Synthesis Example 1, it was confirmed that the isocyanate group content was 0.1% or less. Thereby, urethane acrylate oligomer 5 was obtained.

[Example 1]
(1) Preparation of curable composition 30 parts by mass of urethane acrylate oligomer 1, 70 parts by mass of triethylene glycol diacrylate (manufactured by Kyoeisha Chemical Co., Ltd., Light Acrylate 3EG-A), photopolymerization initiator (manufactured by IGM, Omnirad TPO- L) 2 parts by mass were mixed and thoroughly stirred to obtain a curable composition.

(2) Preparation of Sheet A polypropylene sheet with a thickness of 140 μm was used as the base layer. A resin composition containing an acrylic resin and a urethane resin was applied to one side of the base layer to form a primer layer with a thickness of 2 μm. The above-mentioned curable composition was applied onto the primer layer at a dry coating weight of 5 g/m ² to form a coating layer. The coating layer is pre-cured by irradiating ultraviolet rays using a UV irradiation device consisting of an LED (LED-UV irradiation, wavelength 395 nm, maximum illuminance 0.6 W/cm ² , cumulative light amount 30 mJ/cm ² ). I did it. Next, ultraviolet rays were irradiated using an excimer light irradiation device (excimer irradiation, wavelength 172 nm (Xe ² ), ultraviolet output density 30 mW/cm ² , integrated light amount 30 mJ/cm ² , nitrogen atmosphere). Further, an electron beam was irradiated (acceleration voltage: 125 kV, irradiation dose: 50 kGy) to form a surface layer.

[Examples 2 to 5 and Comparative Examples 1 to 3]
A sheet was produced in the same manner as in Example 1, except that a curable composition having the composition shown in Table 1 below was used.

Note that the acrylic monomer 1 is triethylene glycol diacrylate (Light Acrylate 3EG-A, manufactured by Kyoeisha Chemical Co., Ltd.). Acrylic monomer 2 is 1-6 hexanediol diacrylate (Light Acrylate 1.6HX-A, manufactured by Kyoeisha Chemical Co., Ltd.).
Acrylic monomer 3 is dipentaerythritol hexaacrylate (KAYARAD DPHA, manufactured by Nippon Kayaku).

[evaluation]
(1) Surface shape The Rz (maximum height) and RSm (average length of curved elements) of the sheets obtained in Examples and Comparative Examples were determined in accordance with JIS B0601:2013, and specifically by the following method. It was measured by A rectangular (1024 μm x 768 μm) sample at 10 arbitrary locations was analyzed using a shape analysis laser microscope (“VK-X150 (control unit)/VK-X160 (measurement unit)” manufactured by Keyence Corporation) with an objective lens of 50 mm. Measurement was performed at a laser wavelength of 658 nm, a measurement mode: surface shape mode, a measurement pitch: 0.13 μm, and a measurement quality: high speed mode. The average values of the measured values at ten arbitrary locations were defined as Rz (maximum height) and RSm (average length of curved element).

Further, from optical microscope images of the sheets obtained in Examples and Comparative Examples, it was confirmed that the sheets had a wrinkle structure on the surface.

(2) 60° gloss value The sheets obtained in the examples and comparative examples were measured for 60° specular gloss using a gloss meter (“Microgloss” manufactured by BYK Gardner) in accordance with JIS K5600-4-7. It was measured.

(3) Hoffman Scratch Test The sheets obtained in the Examples and Comparative Examples were subjected to the Hoffman Scratch Test to evaluate their scratch resistance. Using a Hoffman Scratch Hardness Tester ("Hoffman Scratch Hardness Tester" manufactured by BYK Gardner), set the scratch blade so that it touches the sheet surface at an angle of 45 degrees, and move it at a speed of 100 mm/sec to test the surface. I rubbed it. It was visually confirmed whether there were any scratches on the coating surface, and if no scratches were found, the test was repeated by increasing the load applied to the scratch blade. When scratches were confirmed with the naked eye, the load applied to the scratch blade at that time was defined as the scratch generation load.

(4) Weather resistance The sheets obtained in the examples and comparative examples were subjected to an accelerated weather resistance test using a metal halide lamp (MWOM) ("Daipura Metal Weather" manufactured by Daipra Wintes). Specifically, after irradiating ultraviolet rays for 20 hours under the conditions of illuminance: 65 mW/cm ² , black panel temperature: 63° C., and chamber humidity: 50% RH, illuminance: 0 mW/cm ² and chamber humidity: 98%. A test was conducted in which the above cycle was repeated for 400 hours, with the step of condensing water for 4 hours under RH conditions being defined as one cycle. The sheet surface after the test was visually observed and evaluated based on the following criteria.
A: No significant change in appearance.
B: Cracks or peeling occurred.

The sheets of Examples 1 to 5 have a RSm within a predetermined range, and since the surface layer contains a polymer having a predetermined repeating unit, the 60° gloss value is small and the matting effect is excellent. , and had excellent scratch resistance. On the other hand, the sheet of Comparative Example 1 had poor scratch resistance because the polymer contained in the surface layer did not have a repeating unit containing a cyclic structure. Furthermore, since the sheet of Comparative Example 2 had a large RSm, the 60° gloss value was large and the matting effect was low. In addition, in the sheet of Comparative Example 3, since the polymer contained in the surface layer did not have a repeating unit containing a polyoxyalkylene group, the RSm was large, the 60° gloss value was large, and the matting effect was low. Ta.

Further, from a comparison between Examples 1 to 4 and Example 5, it was found that the polymer contained in the surface layer has a repeating unit containing an alicyclic hydrocarbon ring structure or an isocyanurate ring as a repeating unit containing a cyclic structure. In some cases, it has been confirmed that the weather resistance is also excellent.

1... Surface layer 4... Base material layer 5... Transparent resin layer 6... Adhesive layer 7... Decorative layer 8... Separator layer 10, 10A, 10B... Sheet 100A, 100B, 100C... Article

Claims (19)

A sheet having a surface layer,
One surface of the surface layer has a surface shape having a wrinkled structure,
RSm (average length of curved elements) of the surface shape specified in JIS B0601:2013 is 50 μm or less,
A sheet in which the surface layer contains a polymer having a first repeating unit containing a cyclic structure and a second repeating unit containing a polyoxyalkylene group. The sheet according to claim 1, wherein the cyclic structure is at least one of an alicyclic hydrocarbon ring structure and an isocyanurate ring structure. The first repeating unit is a repeating unit derived from a first polymerizable compound containing an ionizing radiation-curable functional group and the cyclic structure,
The sheet according to claim 1 or 2, wherein the second repeating unit is a repeating unit derived from a second polymerizable compound containing an ionizing radiation-curable functional group and the polyoxyalkylene group. The sheet according to claim 3, wherein the first polymerizable compound is a polymerizable oligomer, and the second polymerizable compound is at least one of a polymerizable oligomer and a polymerizable monomer. The sheet according to any one of claims 1 to 4, wherein the first repeating unit further includes the polyoxyalkylene group, and the first repeating unit also serves as the second repeating unit. A sheet according to any of claims 1 to 5, wherein the surface layer contains a wrinkle-forming stabilizer. The sheet according to any one of claims 1 to 6, wherein the Rz (maximum height) defined in JIS B0601:2013 of the surface shape is 3 μm or more. The sheet according to any one of claims 1 to 7, further comprising a base layer on a surface of the surface layer opposite to the surface having the surface shape. The sheet according to claim 8, further comprising a decorative layer between the surface layer and the base layer. The sheet according to claim 8 or 9, further comprising a transparent resin layer between the surface layer and the base layer. An article having a sheet according to any one of claims 1 to 10 on its surface. A decorative sheet comprising the sheet according to any one of claims 1 to 10. A decorative material comprising an adherend and the decorative sheet according to claim 12 disposed on one surface of the adherend. A curable composition used for a surface layer having a surface shape having a wrinkled structure,
A curable composition containing a first polymerizable compound containing a cyclic structure and a second polymerizable compound containing a polyoxyalkylene group. The curable composition according to claim 14, wherein the cyclic structure is at least one of an alicyclic hydrocarbon ring structure and an isocyanurate ring structure. 15. The first polymerizable compound includes an ionizing radiation-curable functional group and the cyclic structure, and the second polymerizable compound includes an ionizing radiation-curable functional group and the polyoxyalkylene group. 16. The curable composition according to 15. The first polymerizable compound is a polymerizable oligomer, and the second polymerizable compound is at least one of a polymerizable oligomer and a polymerizable monomer. The curable composition described in section. Curing according to any one of claims 14 to 17, wherein the first polymerizable compound further includes the polyoxyalkylene group, and the first polymerizable compound also serves as the second polymerizable compound. sexual composition. 19. A curable composition according to any of claims 14 to 18, containing a wrinkle-forming stabilizer.

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