Laminate, decorative material, transfer sheet, and method for manufacturing laminate
The laminate achieves a uniformly smooth matte surface with visually distinguishable three-dimensional design by varying surface roughness ratios and recessed base layer design.
Patent Information
- Application Number
- JP2023112493
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-07-07
- Publication Date
- 2025-01-20
AI Technical Summary
Conventional methods struggle to achieve a uniformly smooth matte surface with a visually distinguishable three-dimensional design by varying the matte effect in specific regions.
A laminate with a matte layer having regions of different thicknesses and surface roughness values, where the ratio of these values exceeds 1.5, and a recessed base layer to create distinct matte effects.
The laminate provides a uniformly smooth feel with visually discernible differences in matte effect between regions, enhancing the three-dimensional design.
Smart Images

Figure 2025009469000001_ABST
Abstract
Description
[Technical field]
[0001] The present disclosure relates to a laminate, a decorative material, a transfer sheet, and a method for producing a laminate. [Background technology]
[0002] As a method for producing a matte article, a method has been proposed in which an uneven surface having a wrinkled structure is formed on the surface of a resin using light such as excimer light. One example of a method for producing such an uneven surface is disclosed in Patent Document 1. In Patent Document 1, first, an excimer light is irradiated onto the surface of a coating film made of a photocurable resin. Then, the coating film is irradiated with ultraviolet light to cure the entire coating film. As a result, a wrinkled structure is formed on the surface of the coating film. In Patent Document 1, a coating film having low gloss is obtained due to the wrinkled structure thus formed. In addition, a matte article having such an uneven surface on its surface provides a smooth feel. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] Patent Publication No. 2021-24102 Summary of the Invention [Problem to be solved by the invention]
[0004] There is a need for such matte articles to have a smooth feel while still being able to vary the degree of matteness of the surface, but with conventional techniques, it has been difficult to vary the degree of matteness of the surface of a matte article in a desired pattern.
[0005] An embodiment of the present disclosure aims to provide a matte article that has a uniformly smooth feel overall, yet allows the difference in the matte effect between the first and second regions to be visually recognized, and has a three-dimensional design. [Means for solving the problem]
[0006] A laminate according to one embodiment of the present disclosure comprises: [1] A laminate having a matte layer having a wrinkled structure on its surface, The matte layer includes a first region and a second region having different thicknesses, When the value of the average length RSm in the first region as specified in JIS B0601:2013 is RSm1, and the value of the average length RSm in the second region as specified in JIS B0601:2013 is RSm2, the maximum value of the ratio of RSm1 to RSm2 (RSm1 / RSm2) or the maximum value of the ratio of RSm2 to RSm1 (RSm2 / RSm1) is 1.5 or more.
[0007] A laminate according to one embodiment of the present disclosure comprises: [2] A laminate having a matte layer having a wrinkled structure on a surface thereof, The matte layer includes a first region and a second region having different thicknesses, The laminate is a laminate in which a degree of matteness of the first surface in the first region and a degree of matteness of the first surface in the second region are visually perceived to be different from each other.
[0008] [3] A film comprising a first surface and a second surface, and a base layer and a matte layer in this order from the second surface to the first surface; the base layer has a recess on a surface facing the matte layer; The laminate according to [1] or [2], wherein the first region of the matte layer is a region that overlaps with the recess in a planar view, and the second region is a region that does not overlap with the recess in a planar view.
[0009] A laminate according to one embodiment of the present disclosure comprises: [4] The laminate according to any one of [1] to [3], wherein the difference in height between the first region and the second region is less than 10 μm.
[0010] A laminate according to one embodiment of the present disclosure comprises: [5] Further comprising a pattern layer having a pattern, The laminate according to any one of [1] to [4], wherein the first region and the second region are arranged according to the pattern.
[0011] The decorative material according to one embodiment of the present disclosure comprises: [6] A laminate according to any one of [1] to [5], A decorative material comprising the laminate and a supporting material laminated thereon.
[0012] The decorative material according to one embodiment of the present disclosure comprises: [7] The decorative material according to [6], wherein the support material is a building material.
[0013] The decorative material according to one embodiment of the present disclosure comprises: [8] A laminate according to any one of [1] to [5], A decorative material comprising the laminate and a molded resin part laminated therewith.
[0014] The transfer sheet according to one embodiment of the present disclosure comprises: [9] A laminate according to any one of [1] to [4], a cured resin layer including a cured product of an ionizing radiation curable resin; The cured resin layer is a transfer sheet that is in contact with the first surface and has a wrinkled structure.
[0015] The transfer sheet according to one embodiment of the present disclosure comprises:
[10] Further comprising a pattern layer having a pattern, The transfer sheet according to [9], wherein the cured resin layer is located between the design layer and the laminate.
[0016] A method for producing a laminate according to one embodiment of the present disclosure includes:
[11] A method for producing a laminate comprising a base layer having a first surface with a recess, and a matte layer disposed opposite the first surface, comprising: laminating a resin layer on the base layer so as to fill the recess; and a step of irradiating the resin layer with light having a wavelength of 100 nm or more and 380 nm or less to form the matte layer from the resin layer. Effect of the Invention
[0017] According to one embodiment of the present disclosure, a matte article can be provided that has a uniformly smooth feel overall, while allowing the difference in the matte effect between the first region and the second region to be visually recognized, and has a three-dimensional design. [Brief description of the drawings]
[0018] [Figure 1] FIG. 1 is a diagram for explaining one embodiment of the present disclosure, and is a cross-sectional view showing an example of a decorative material including a laminate. [Diagram 2] FIG. 2 is a plan view of an example of a wrinkled structure of a laminate. [Diagram 3] FIG. 3 is a cross-sectional view illustrating an example of a method for producing a laminate. [Figure 4] FIG. 4 is a cross-sectional view illustrating an example of a method for producing a laminate. [Diagram 5] FIG. 5 is a cross-sectional view illustrating an example of a method for producing a laminate. [Figure 6] FIG. 6 is a cross-sectional view illustrating an example of a method for producing a laminate. [Figure 7] FIG. 7 is a cross-sectional view showing another example of a decorative material including a laminate. [Figure 8] FIG. 8 is a plan photograph showing an example of the wrinkle structure of the laminate of FIG. [Figure 9] FIG. 9 is a cross-sectional view showing still another example of a decorative material including a laminate. [Figure 10] FIG. 10 is a cross-sectional view showing an example of a method for producing a transfer sheet. [Figure 11] FIG. 11 is a cross-sectional view showing an example of a transfer sheet having a laminate. [Figure 12] FIG. 12 is a cross-sectional view showing an example of a transferred sheet produced using a transfer sheet. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The aspect ratios and the like in the drawings attached to this specification are changed from the actual aspect ratios and the like. Note that the embodiments shown below are examples of the present disclosure. Therefore, the present disclosure should not be interpreted as being limited to these embodiments.
[0020] In this specification, the terms "plate," "sheet," and "film" are not distinguished from one another solely based on differences in name. For example, "sheet" includes members called "plate" or "film."
[0021] In addition, the term "sheet surface" refers to the surface that coincides with the direction in which the target sheet-like member extends when the target sheet-like member is viewed as a whole. In addition, the normal direction used for a sheet-like member refers to the direction in which the normal to the sheet surface of the member extends. The same applies to terms such as "plate surface" and "film surface."
[0022] In this specification, "planar view" refers to the state in which a target sheet-like (plate-like, film-like) member is viewed from the normal direction of the member. For example, when a certain plate-like member "has a rectangular shape in a planar view," it means that the member has a rectangular shape when viewed from the normal direction to the plate surface.
[0023] Terms used in this specification that specify shapes, geometric conditions, and physical characteristics and their degrees are not strictly limited to their ranges, but include the ranges within which similar functions can be expected. These terms include, for example, terms such as "parallel," "orthogonal," and "same." Ranges that indicate values of length, angle, area, volume, weight, and physical characteristics are not strictly limited to their ranges, but include the ranges within which similar functions can be expected. However, unless otherwise specified, the terms should be interpreted strictly.
[0024] The laminate 20 according to the embodiment of the present disclosure is used as a member constituting the outermost layer of the interior and exterior of buildings, the surfaces of fittings, furniture, and home appliances, the interior of vehicles, and the like. More specifically, the laminate 20 may be used as, for example, interior components of buildings such as walls, ceilings, and floors, exterior components such as exterior walls, eaves ceilings, roofs, fences, and fences, fittings or fixtures such as window frames, doors, door frames, handrails, skirting boards, moldings, and other fittings or fixtures, general furniture such as chests of drawers, shelves, and desks, kitchen furniture such as dining tables and sinks, surface decorative panels such as cabinets for home appliances and office automation equipment, and interior and exterior components of vehicles. The laminate 20 may also be used as packaging materials, anti-glare films for displays, whiteboards (whiteboards) or blackboards, various cards such as credit cards, cash cards, telephone cards, and various certificates, various keyboard keys, transparent plates (window glass, etc.) such as windows, doors, and partitions, artificial leather, and the like. The uses of the laminate 20 are not limited to those listed here.
[0025] FIG. 1 is a diagram illustrating an embodiment of the present disclosure, and is a cross-sectional view showing an example of a decorative material 10 including a laminate 20. The decorative material 10 of this embodiment includes a support material 12 and a laminate 20. The laminate 20 is laminated on the support material 12. The laminate 20 includes a first surface 20a and a second surface 20b. The second surface 20b faces the support material 12. The first surface 20a is located opposite the support material 12. The first surface 20a constitutes the surface of the laminate 20 and the surface of the decorative material 10.
[0026] The support material 12 supports the laminate 20. The support material 12 is disposed facing the second surface 20b of the laminate 20. The support material 12 may be a sheet-like member. The thickness of the support material 12 may be 10 μm or more and 1 mm or less. Preferably, the thickness of the support material 12 may be 20 μm or more and 300 μm or less. The support material 12 may be a building material. The building material may be, for example, interior components of a building such as walls, ceilings, and floors, exterior components such as exterior walls, eaves ceilings, roofs, fences, and fences, and fittings or fixtures such as window frames, doors, door frames, handrails, baseboards, moldings, and other building materials.
[0027] The material of the support material 12 may be, for example, a resin material, a metal material, or a fibrous material. The resin material may be, for example, a polyester resin such as polyethylene terephthalate, an olefin resin such as polyethylene or polypropylene, a vinyl chloride resin such as polyvinyl chloride, or an acrylic resin. The metal material may be, for example, aluminum, iron, copper, gold, silver, chromium, nickel, cobalt, tin, titanium, or an alloy thereof. The fibrous material may be, for example, paper, woven fabric, nonwoven fabric, or a material impregnated with resin. The support material 12 may include only one layer made of these materials. The support material 12 may also include multiple layers made of these materials. When the support material 12 includes multiple layers, the multiple layers may be made of different materials.
[0028] The laminate 20 includes the base layer 30 and the matte layer 40 in this order from the second surface 20b to the first surface 20a. In particular, in this embodiment, the laminate 20 further includes the design layer 50 and the adhesive layer 58. In the example shown in FIG. 1, the laminate 20 includes the design layer 50, the adhesive layer 58, the base layer 30, and the matte layer 40 in this order from the second surface 20b to the first surface 20a. Note that neither the design layer 50 nor the adhesive layer 58 is an essential component of the laminate 20. The laminate 20 may not include one or more of the design layer 50 and the adhesive layer 58. The laminate 20 may also include other members (layers) intended to perform a specific function.
[0029] The design layer 50 has a function of displaying a design to be visually recognized by an observer who observes the laminate 20. This design may be, for example, a picture, a photograph, a figure, a pattern, a mark, a character, a color, or other picture. The design layer 50 may display a monochromatic color picture as a design. As an example, the design displayed by the design layer 50 may be a wood grain pattern. The design layer 50 is disposed facing the second surface 40b of the matte layer 40. In this embodiment, the design layer 50 is disposed between the support material 12 and the matte layer 40. The thickness of the design layer 50 may be 0.5 μm or more and 20 μm or less. Preferably, the thickness of the design layer 50 may be 1 μm or more and 10 μm or less. More preferably, the thickness of the design layer 50 may be 2 μm or more and 5 μm or less.
[0030] The design layer 50 may include a colored layer 52 and a pattern layer 54. The colored layer 52 is a layer that imparts a desired color to the entire surface of the support material 12. The colored layer 52 may be a so-called solid layer. The colored layer 52 may have a single color. The colored layer 52 may also have a pattern composed of multiple colors. The pattern layer 54 is a layer that constitutes the design to be displayed by the design layer 50. The colored layer 52 and the pattern layer 54 may be formed by coating, printing, or the like using ink. For example, an ink containing a binder resin and a colorant such as a pigment or dye may be used as the ink. The design layer 50 may have only one of the colored layer 52 and the pattern layer 54. That is, the design layer 50 may have only the colored layer 52 or only the pattern layer 54.
[0031] The adhesive layer 58 has a function of bonding the design layer 50 and the base layer 30 to each other. When the laminate 20 does not have the design layer 50, the adhesive layer 58 may bond the support material 12 and the base layer 30 to each other. As a material for the adhesive layer 58, for example, an adhesive such as a urethane adhesive, an acrylic adhesive, an epoxy adhesive, or a rubber adhesive may be used. The thickness of the adhesive layer 58 may be 0.1 μm or more and 30 μm or less. Preferably, the thickness of the adhesive layer 58 may be 1 μm or more and 15 μm or less. More preferably, the thickness of the adhesive layer 58 may be 2 μm or more and 10 μm or less.
[0032] The base layer 30 supports the matte layer 40. The base layer 30 is disposed facing the second surface 40b of the matte layer 40. In this embodiment, the base layer 30 is disposed between the design layer 50 and the matte layer 40. The base layer 30 includes a first surface 30a facing the matte layer 40 and a second surface 30b facing away from the matte layer 40. In the example shown in FIG. 1, the second surface 40b of the matte layer 40 and the first surface 30a of the base layer 30 face each other.
[0033] The base layer 30 may be formed of a resin material. The resin material may be, for example, a polyolefin resin, a polyester resin, a polycarbonate resin, an acrylonitrile-butadiene-styrene resin (ABS resin), an acrylic resin, a vinyl chloride resin, or the like. The base layer 30 may contain additives such as a weathering agent, an ultraviolet absorber, a light stabilizer, or a colorant. The thickness of the base layer 30 may be 10 μm or more and 300 μm or less. Preferably, the thickness of the base layer 30 may be 20 μm or more and 200 μm or less. More preferably, the thickness of the base layer 30 may be 30 μm or more and 150 μm or less.
[0034] The total light transmittance of the base layer 30 as defined in JIS K7375:2008 may be 50% or more. Preferably, the total light transmittance of the base layer 30 may be 80% or more.
[0035] As shown in FIG. 1, a recess 32 is formed on the first surface 30a of the base layer 30. In the example shown in FIG. 1, the recess 32 has a bottom surface 34 and two side surfaces 36, 38. The bottom surface 34 may extend parallel to the first surface 30a. The side surfaces 36, 38 may be inclined surfaces connecting the first surface 30a and the bottom surface 34. The side surfaces 36, 38 may be inclined with respect to both the first surface 30a and the normal line of the first surface 30a so as to approach each other from the first surface 30a toward the bottom surface 34. In the cross section shown in FIG. 1, the bottom surface 34 and the side surfaces 36, 38 extend linearly, but this is not limited thereto. In the cross section shown in FIG. 1, the bottom surface 34 and the side surfaces 36, 38 may include a portion extending in a curved line or a portion extending in a broken line.
[0036] In this embodiment, as described later, the matte layer 40 is provided so as to fill the recess 32. The recess 32 is provided to make the matte degree of the first surface 20a (the first surface 40a of the matte layer 40) of the laminate 20 in the first region A1 overlapping the recess 32 in a plan view different from the matte degree of the first surface 20a (the first surface 40a of the matte layer 40) of the laminate 20 in the second region A2 not overlapping the recess 32. The reason why the matte degree of the first region A1 and the matte degree of the second region A2 differ due to the presence of the recess 32 will be described later. The recess 32 is arranged in a portion intended to visually distinguish the first region A1 from the second region A2. For example, when the design layer has a wood grain pattern, the recess 32 may be formed in a portion corresponding to the conduit.
[0037] The depth D32 of the recess 32 may be 5 μm or more and 100 μm or less. Preferably, the depth D32 may be 10 μm or more and 80 μm or less. More preferably, the depth D32 may be 20 μm or more and 60 μm or less. The depth D32 is measured as follows. The base layer 30 is observed using an optical microscope at a cross section along the thickness direction of the base layer 30. The depth D32 is defined as the length along the normal direction of the base layer 30 from the first surface 30a in a region adjacent to the recess 32 to be measured, where no recess 32 exists, to the deepest point in the recess 32.
[0038] The width W32 of the recess 32 may be 10 μm or more and 500 μm or less. Preferably, the width W32 may be 50 μm or more and 400 μm or less. More preferably, the width W32 may be 100 μm or more and 300 μm or less.
[0039] When the recess 32 extends linearly in a plan view of the base layer 30, i.e., when the recess 32 has a clear longitudinal direction, the width W32 is measured along a direction perpendicular to the extension direction of the recess 32 and parallel to the sheet surface of the base layer 30. When the width of the recess 32 varies along the thickness direction of the base layer 30, the maximum width value among the width values that vary along the thickness direction is defined as the width W32 of the recess 32.
[0040] When the recess 32 does not have a clear longitudinal direction in the plan view of the base layer 30, the width W32 is measured as follows. In the plan view of the base layer 30, the recess 32 is sandwiched between any two parallel straight lines, and the distance between the two straight lines is measured. The distance between the two straight lines is the shortest distance between the two straight lines. The angle of the two straight lines is changed within the sheet surface of the base layer 30, and the distance between the two straight lines is measured. The maximum distance between the two straight lines is the width W32 of the recess 32.
[0041] The recesses 32 are formed, for example, by embossing, molding, sandblasting, etching, or the like.
[0042] In order to improve the adhesion between the base layer 30 and the matte layer 40, a primer layer may be provided between the base layer 30 and the matte layer 40. The primer layer is formed of, for example, a resin material. The resin material may be a resin such as a urethane resin, an acrylic polyol resin, an acrylic resin, an ester resin, an amide resin, a butyral resin, a styrene resin, a urethane-acrylic copolymer, a polycarbonate-based urethane-acrylic copolymer, a vinyl chloride-vinyl acetate copolymer resin, a vinyl chloride-vinyl acetate-acrylic copolymer resin, a chlorinated propylene resin, a nitrocellulose resin, or a cellulose acetate resin. The primer layer may contain additives such as an ultraviolet absorber and a light stabilizer, as necessary. The thickness of the primer layer may be 0.1 μm or more and 10 μm or less. Preferably, the thickness of the primer layer may be 1 μm or more and 8 μm or less. More preferably, the thickness of the primer layer may be 2 μm or more and 6 μm or less.
[0043] The matte layer 40 is a layer that exerts a matte effect on the surface (first surface 20a) of the laminate 20. The matte layer 40 includes a first surface 40a and a second surface 40b. The first surface 40a and the second surface 40b face opposite to each other. When the laminate 20 has a support material 12, the first surface 40a faces away from the support material 12, and the second surface 40b faces the support material 12. The first surface 40a constitutes the surface of the matte layer 40 and also constitutes the first surface 20a of the laminate 20. The first surface 40a is a surface having fine irregularities, a so-called matte surface. Light that enters the matte layer 40 is diffusely reflected and diffused by this first surface 40a. As a result, the gloss on the surface of the matte layer 40 is reduced. That is, the matte effect is exerted in the matte layer 40.
[0044] In this embodiment, the matte layer 40 is provided so as to fill the recess 32 of the base layer 30. The matte layer 40 is provided so as to fill the recess 32 means that the matte layer 40 completely or mostly fills the recess 32. That is, it means that the first surface 40a of the matte layer 40 in the first region A1 is located opposite the second surface 30b of the base layer 30 with respect to the first surface 30a of the base layer 30 in the second region A2.
[0045] In this embodiment, the matte layer 40 includes a resin layer 41 and a plurality of particles 47. The resin layer 41 constitutes a main body portion of the matte layer 40. The first surface 40a is formed on the surface of the resin layer 41. That is, the resin layer 41 has the first surface 40a. The first surface 40a has a wrinkle structure 45. The plurality of particles 47 function as a wrinkle forming agent for imparting a specific wrinkle structure 45 to the first surface 40a.
[0046] The wrinkle structure 45 is a structure including a streak-like uneven structure (see FIG. 2). In particular, the wrinkle structure 45 of this embodiment includes streak-like protrusions and / or streak-like recesses. The streak-like protrusions and / or streak-like recesses have irregular shapes and are irregularly arranged in a plan view. The wrinkle structure 45 may include a plurality of curved streak-like protrusions and a recess formed by being surrounded by the plurality of protrusions. The wrinkle structure 45 may also include a plurality of curved streak-like recesses and a protrusion formed by being surrounded by the plurality of recesses. "Curved" means that the extension direction of one streak-like protrusion or recess has an inverted portion in a plan view where the extension direction of one streak-like protrusion or recess is inverted from one side to the other side. The wrinkle structure 45 may include a meandering streak-like protrusion and a recess formed by being surrounded by the meandering streak-like protrusion. The wrinkle structure 45 may also include a meandering streak-like recess and a protrusion formed by being surrounded by the meandering streak-like recess. "Meandering" means that, in a plan view, one streak-like convex or concave portion includes two or more inverted portions, and the extension directions of the convex or concave portions in two adjacent inverted portions in one convex or concave portion are reversed to opposite directions from each other.
[0047] The height difference between the first region A1 and the second region A2 on the first surface 40a of the matte layer 40 may be less than 10 μm. This allows the first surface 40a to have a uniformly smooth feel. Therefore, when touching the first surface 40a with a hand, the unevenness is unlikely to be felt. Preferably, the height difference between the first region A1 and the second region A2 may be less than 8 μm. More preferably, the height difference between the first region A1 and the second region A2 may be less than 5 μm. More preferably, the height difference between the first region A1 and the second region A2 may be less than 3 μm.
[0048] The height difference between the first region A1 and the second region A2 on the first surface 40a of the matte layer 40 is measured by using a contact surface roughness and shape measuring instrument and calculating from the "ordinate value" as specified in 3.2.8 of JIS B0601:2013. The heights in the second region A2 and the first region A1 are determined by taking the average of the ordinate values of the region that has no gradient due to anything other than the wrinkle shape within the region, and measuring the difference between these two heights as the height difference between the first region A1 and the second region A2. The shape of the stylus and the standard cutoff value of the roughness curve are appropriately selected according to the uneven shape of the sample to be measured.
[0049] As described above, the first surface 40a of the matte layer 40 constitutes the first surface 20a of the laminate 20. In this specification, the first surface 40a of the matte layer 40 and the first surface 20a of the laminate 20 may be collectively referred to as the first surface 20a, 40a. The first surface 20a, 40a includes a first region A1 that overlaps with the recess 32 of the base layer 30 in a plan view, and a second region A2 that does not overlap with the recess 32 in a plan view (see FIG. 1). The wrinkle structure 45 is formed over the entire area of the first region A1 and the second region A2. That is, the first region A1 and the second region A2 do not include any region in which the wrinkle structure 45 is not formed.
[0050] FIG. 2 is a plan view showing an example of the wrinkle structure 45 of the laminate 20 shown in FIG. 1. In the example shown in FIG. 2, the recess 32 extends along the vertical direction. Therefore, the vertical direction in FIG. 2 is the extension direction of the recess 32, and the horizontal direction is the width direction of the recess 32. In the example shown in FIG. 2, in the second region A2, the wrinkle structure 45 of the first surface 20a, 40a includes isotropic and fine wrinkle-like unevenness as a whole. In contrast, in the first region A1, the wrinkle structure 45 of the first surface 20a, 40a includes many convex portions extending in the width direction of the recess 32 and many concave portions extending in the width direction of the recess 32. As a result, the appearance of the wrinkle structure 45 of the first region A1 and the appearance of the wrinkle structure 45 of the second region A2 in a plan view are different from each other. This difference in appearance can be evaluated by the difference in the average length RSm on the first surfaces 20a, 40a. The average length RSm on the first surfaces 20a and 40a will be described below.
[0051] The value of the average length RSm in the first region A1 is RSm1. The value of the average length RSm in the second region A2 is RSm2. The average length RSm in this specification is the "average length of roughness curve elements" specified in 4.3.1 of JIS B0601:2013. The average length RSm is a lateral parameter of the profile curve, and is the average of the lengths of the profile curve elements in the reference length. The smaller the average length RSm, the narrower the width of the convex and concave portions, indicating that the surface shape tends to have narrower convex and concave portions. The average length RSm is measured using a laser microscope.
[0052] RSm1 and RSm2 may be 5 μm or more and 500 μm or less. Preferably, RSm1 and RSm2 may be 10 μm or more and 400 μm or less. More preferably, RSm1 and RSm2 may be 20 μm or more and 300 μm or less.
[0053] In this embodiment, the maximum value of the ratio of RSm1 to RSm2 (RSm1 / RSm2) or the maximum value of the ratio of RSm2 to RSm1 (RSm2 / RSm1) is 1.5 or more. Preferably, the maximum value of RSm1 / RSm2 or the maximum value of RSm2 / RSm1 is 2.0 or more. More preferably, the maximum value of RSm1 / RSm2 or the maximum value of RSm2 / RSm1 is 3.0 or more. Moreover, the maximum value of RSm1 / RSm2 or the maximum value of RSm2 / RSm1 is 10.0 or less. Preferably, the maximum value of RSm1 / RSm2 or the maximum value of RSm2 / RSm1 is 8.0 or less. More preferably, the maximum value of RSm1 / RSm2 or the maximum value of RSm2 / RSm1 is 6.0 or less.
[0054] The maximum value of the RSm1 / RSm2 value and the maximum value of the RSm2 / RSm1 value are the maximum values of the ratios of 18 RSm values measured along 18 directions inclined from each other at 10° intervals. More specifically, first, the RSm value (RSm1) of the first region A1 and the RSm value (RSm2) of the second region A2 are measured in each of the 18 directions inclined from each other at 10° intervals. Next, the ratio (RSm1 / RSm2) of RSm1 of the first region A1 to RSm2 of the second region A2 and the ratio (RSm2 / RSm1) of RSm2 of the second region A2 to RSm1 of the first region A1, which are measured in the same direction, are calculated. This results in the calculation of 18 RSm1 / RSm2 values and 18 RSm2 / RSm1 values. The maximum value of these 18 RSm1 / RSm2 values is defined as the "maximum value of the ratio (RSm1 / RSm2) of RSm1 to RSm2." The maximum value among the 18 RSm2 / RSm1 values is defined as the "maximum value of the ratio (RSm2 / RSm1) of RSm2 to RSm1." The RSm value of the first region A1 is measured at the center in the width direction of the recess 32. The RSm value of the second region is measured at a location 50 μm or more away from the contour of the recess 32 along the sheet surface of the laminate 20.
[0055] 2, in the first region A1, the wrinkle structure 45 includes many convex portions extending in the width direction of the recess 32 and many concave portions extending in the width direction of the recess 32. In this case, the value of RSm1 measured along the width direction of the recess 32 is larger than the value of RSm1 measured along the width direction of the recess 32. On the other hand, in the second region A2, the wrinkle structure 45 of the first surface 20a, 40a includes isotropic and fine wrinkle-like unevenness as a whole. In this case, the variation in the value of RSm2 depending on the measurement direction (angle) is small.
[0056] By making the maximum value of RSm1 / RSm2 or the maximum value of RSm2 / RSm1 1.5 or more, the difference between the specular gloss of the first surfaces 20a, 40a in the first region A1 and the specular gloss of the first surfaces 20a, 40a in the second region A1 can be increased. As a result, when an observer observes the laminate 20, the matte degree of the first surfaces 20a, 40a in the first region A1 and the matte degree of the first surfaces 20a, 40a in the second region A2 are visually recognized as being different from each other. For example, when an observer observes the laminate 20, the height in the thickness direction of the first surfaces 20a, 40a in the first region A1 and the height in the thickness direction of the first surfaces 20a, 40a in the second region A2 are visually recognized as being different from each other. As a result, it is possible to provide a matte article that has a smooth feel due to the wrinkle structure 45, while being capable of controlling the matte degree of the surface.
[0057] In this specification, the specular gloss of the first surfaces 20a and 40a is the 60° specular gloss (G S (60°)). Specular gloss (G S (60°)) is measured using a gloss meter. As the gloss meter, for example, a micro-gloss gloss meter manufactured by BYK-Gardner may be used.
[0058] The specular gloss (G S (60°)) may be greater than 0 and less than or equal to 3.0. Preferably, the specular gloss (GS (60°)) may be 2.5 or less. More preferably, the specular gloss (G S (60°)) may be 2.0 or less.
[0059] In this embodiment, the first region A1 and the second region A2 are arranged according to the pattern of the design layer 50. For example, the first region A1 and the second region A2 are arranged according to the arrangement of the pattern layer 54 of the design layer 50. The first region A1 and the second region A2 are arranged according to the pattern including the case where the first region A1 is arranged so as to overlap with the pattern layer 54 and the case where the second region A2 is arranged so as to overlap with the pattern layer 54. In this case, it is not necessary for all of the first region A1 or the second region A2 to overlap with the pattern layer 54. When 50% or more of the boundary line between the first region A1 and the second region A2 overlaps with the outline of the pattern layer 54 in a plan view of the laminate 20, the first region A1 and the second region A2 are considered to be arranged according to the pattern. Preferably, 70% or more of the boundary line between the first region A1 and the second region A2 may overlap with the outline of the pattern layer 54 in a plan view of the laminate 20. More preferably, in a plan view of the laminate 20, 80% or more of the boundary line between the first region A1 and the second region A2 may overlap with the contour line of the design layer 54.
[0060] The thickness of the matte layer 40 may be 1 μm or more. Preferably, the thickness of the matte layer 40 may be 2 μm or more. More preferably, the thickness of the matte layer 40 may be 3 μm or more. More preferably, the thickness of the matte layer 40 may be 4 μm or more. Also, the thickness of the matte layer 40 may be 300 μm or less. Preferably, the thickness of the matte layer 40 may be 200 μm or less. More preferably, the thickness of the matte layer 40 may be 100 μm or less. More preferably, the thickness of the matte layer 40 may be 50 μm or less. In this embodiment, the thickness of the matte layer 40 means the thickness of the matte layer 40 in the second region A2. Also, the thickness of the matte layer 40 means the thickness of the part of the matte layer 40 where the particles 47 are not present. That is, the thickness of the matte layer 40 is the thickness of the resin layer 41. The thickness of the resin layer 41 is determined by measuring the thickness at 20 points on an image taken with a scanning electron microscope (SEM) of a cross section parallel to the normal direction of the resin layer 41, and calculating the arithmetic mean of the thickness values at 20 points. The accelerating voltage of the SEM is set to 3 kV, and the magnification is set according to the thickness.
[0061] The resin layer 41 includes a resin composition. The resin composition used in the resin layer 41 may include an ionizing radiation curable resin. The ionizing radiation curable resin is a resin having an ionizing radiation curable functional group. The ionizing radiation curable functional group is a group that crosslinks by irradiation with ionizing radiation. The ionizing radiation curable functional group may be a functional group having an ethylenic double bond, such as a (meth)acryloyl group, a vinyl group, or an allyl group. In this specification, a (meth)acryloyl group refers to an acryloyl group or a methcroyl group. In this specification, a (meth)acrylate refers to an acrylate or a methacrylate. In addition, the ionizing radiation refers to an electromagnetic wave or a charged particle beam that has an energy quantum capable of polymerizing and / or crosslinking molecules. As the ionizing radiation, an electromagnetic wave such as ultraviolet light (UV), an electron beam (EB), an X-ray, or a gamma ray, or a charged particle beam such as an alpha ray or an ion beam may be used.
[0062] The ionizing radiation curable resin may be an electron beam curable resin or an ultraviolet ray curable resin. The ionizing radiation curable resin may be appropriately selected from polymerizable monomers and polymerizable oligomers that have been conventionally used as ionizing radiation curable resins.
[0063] As the polymerizable monomer, a (meth)acrylate-based monomer having a radically polymerizable unsaturated group in the molecule is preferable. In particular, as the polymerizable monomer, a polyfunctional (meth)acrylate monomer is preferable. The polyfunctional (meth)acrylate monomer may be a (meth)acrylate monomer having two or more ionizing radiation curable functional groups in the molecule and having at least a (meth)acryloyl group as the functional group. The number of functional groups of the polyfunctional (meth)acrylate monomer may be 2 or more and 8 or less. Preferably, the number of functional groups of the polyfunctional (meth)acrylate monomer may be 2 or more and 6 or less. These polyfunctional (meth)acrylates may be used alone or in combination of two or more.
[0064] The polymerizable oligomer may be, for example, a (meth)acrylate oligomer having two or more ionizing radiation curable functional groups in the molecule and having at least a (meth)acryloyl group as the functional group. The polymerizable oligomer may be, for example, a urethane (meth)acrylate oligomer, an epoxy (meth)acrylate oligomer, a polyester (meth)acrylate oligomer, a polyether (meth)acrylate oligomer, a polycarbonate (meth)acrylate oligomer, an acrylic (meth)acrylate oligomer, etc. Further, the polymerizable oligomer may be a highly hydrophobic polybutadiene (meth)acrylate oligomer having a (meth)acrylate group on the side chain of a polybutadiene oligomer, a silicone (meth)acrylate oligomer having a polysiloxane bond in the main chain, an aminoplast resin (meth)acrylate oligomer obtained by modifying an aminoplast resin having many reactive groups in a small molecule, and an oligomer having a cationically polymerizable functional group in the molecule, such as a novolac type epoxy resin, a bisphenol type epoxy resin, an aliphatic vinyl ether, or an aromatic vinyl ether.
[0065] These polymerizable oligomers may be used alone or in combination. The polymerizable oligomer may be a urethane (meth)acrylate oligomer, an epoxy (meth)acrylate oligomer, a polyester (meth)acrylate oligomer, a polyether (meth)acrylate oligomer, a polycarbonate (meth)acrylate oligomer, or an acrylic (meth)acrylate oligomer. Preferably, the polymerizable oligomer may be a urethane (meth)acrylate oligomer or a polycarbonate (meth)acrylate oligomer. More preferably, the polymerizable oligomer may be a urethane (meth)acrylate oligomer.
[0066] The number of functional groups of these polymerizable oligomers may be 2 or more and 8 or less. Preferably, the number of functional groups of the polymerizable oligomers may be 2 or more and 6 or less. The weight average molecular weight of the polymerizable oligomers may be 2500 or more and 7500 or less. Preferably, the weight average molecular weight of the polymerizable oligomers may be 3000 or more and 7000 or less. More preferably, the weight average molecular weight of the polymerizable oligomers may be 3500 or more and 6000 or less. Here, the weight average molecular weight is an average molecular weight measured by GPC analysis and converted into standard polystyrene.
[0067] In the present embodiment, a combination of a polymerizable oligomer and a polymerizable monomer may be used as the resin forming the resin layer 41. The polymerizable oligomer may be a multifunctional urethane (meth)acrylate oligomer. Preferably, the polymerizable oligomer may be a multifunctional urethane acrylate oligomer. The polymerizable monomer may be a multifunctional polymerizable monomer. Preferably, the polymerizable monomer may be a multifunctional (meth)acrylate monomer. More preferably, the polymerizable monomer may be a multifunctional acrylate monomer. When a combination of a polymerizable oligomer and a polymerizable monomer is used, the content of the polymerizable oligomer may be 40 parts by mass or more relative to 100 parts by mass in total of the polymerizable oligomer and the polymerizable monomer. Preferably, the content of the polymerizable oligomer may be 50 parts by mass or more. More preferably, the content of the polymerizable oligomer may be 60 parts by mass or more. More preferably, the content of the polymerizable oligomer may be 70 parts by mass or more. More preferably, the content of the polymerizable oligomer may be 80 parts by mass or more. The content of the polymerizable oligomer may be 98 parts by mass or less. Preferably, the content of the polymerizable oligomer may be 95 parts by mass or less. More preferably, the content of the polymerizable oligomer may be 92 parts by mass or less.
[0068] The resin composition used in the resin layer 41 may contain other components in addition to the above-mentioned resins depending on the desired performance, etc. For example, the resin composition used in the resin layer 41 may contain a monofunctional (meth)acrylate for the purpose of reducing the viscosity, etc. These monofunctional (meth)acrylates may be used alone or in combination of two or more kinds.
[0069] In addition, when the above-mentioned resin is an ultraviolet-curable resin that is cured by ultraviolet light, additives such as a photopolymerization initiator and a photopolymerization accelerator may be included. As the photopolymerization initiator, for example, one or more selected from acetophenone, benzophenone, α-hydroxyalkylphenone, Michler's ketone, benzoin, benzyl dimethyl ketal, benzoyl benzoate, α-acyloxime ester, thioxanthones, etc. may be used. The photopolymerization accelerator is capable of reducing polymerization inhibition caused by air during curing and accelerating the curing speed. As the photopolymerization accelerator, for example, one or more selected from p-dimethylaminobenzoic acid isoamyl ester, p-dimethylaminobenzoic acid ethyl ester, etc. may be used.
[0070] The particles 47 function as a wrinkle-forming agent for imparting a specific wrinkle structure 45 to the first surface 40a. In the conventional technology for forming a wrinkled uneven surface on the surface of a resin using excimer light or the like, it was difficult to precisely control the shape of the wrinkle structure 45 of the uneven surface. As a result of the inventors' intensive research into this issue, they found that the shape of the wrinkle structure 45 on the first surface 40a can be controlled by further adding the particles 47 to the resin composition for forming the matte layer 40.
[0071] Conventionally, a technique for forming a matte layer by adding particles such as silica to a resin layer not having a wrinkled structure 45 is known. In this technique, unevenness is formed on the surface of the resin layer by particles protruding from the surface, and the unevenness exerts a matte effect. In contrast, in this embodiment, the unevenness on the first surface 40a is realized by the wrinkled structure 45. The particles 47 of this embodiment are not intended to form the unevenness on the first surface 40a by themselves. In this respect, the particles added to the resin layer not having the wrinkled structure 45 and the particles 47 of this embodiment are essentially different. The present inventors speculate that when the resin composition is irradiated with excimer light or the like as in the manufacturing method described later, the particles 47 become the starting point and form the convex portions and / or concave portions constituting the wrinkled structure 45. Hereinafter, such particles 47 will be described.
[0072] As the particles 47, for example, organic particles or inorganic particles may be used. As the organic matter constituting the organic particles, polymethyl methacrylate, acrylic-styrene copolymer resin, melamine resin, polycarbonate, polystyrene, polyvinyl chloride resin, benzoguanamine-melamine-formaldehyde condensate, silicone, fluorine-based resin, polyester-based resin, etc. may be used. As the inorganic matter constituting the inorganic particles, silica, alumina, calcium carbonate, aluminosilicate, barium sulfate, etc. may be used. Among these, preferably, silica may be used as the inorganic matter constituting the inorganic particles. The shape of the particles 47 may be, for example, spherical, polyhedral, scaly, amorphous, etc.
[0073] The average particle diameter of the particles 47 may be 1 μm or more. Preferably, the average particle diameter of the particles 47 may be 1.3 μm or more. More preferably, the average particle diameter of the particles 47 may be 1.5 μm or more. More preferably, the average particle diameter of the particles 47 may be 1.8 μm or more. The average particle diameter of the particles 47 may be 20 μm or less. Preferably, the average particle diameter of the particles 47 may be 15 μm or less. More preferably, the average particle diameter of the particles 47 may be 10 μm or less. In this specification, the average particle diameter of the particles 47 is measured as a mass average value d50 in particle size distribution measurement by a laser light diffraction method.
[0074] The plurality of particles 47 may include particles 47 having a maximum dimension equal to or greater than 1 / 2 the thickness of the resin layer 41. The present inventors have found through their studies that when the plurality of particles 47 include particles 47 having a maximum dimension equal to or greater than 1 / 2 the thickness of the resin layer 41, the shape of the wrinkle structure 45 of the first surface 40a can be more appropriately controlled. Preferably, the plurality of particles 47 may include particles 47 having a maximum dimension equal to or greater than the thickness of the resin layer 41.
[0075] The maximum dimension of the particle 47 is measured in a cross section of the particle 47 observed in a cross section parallel to the normal direction of the matte layer 40. The length of the longest straight line among the straight lines that cross the particle in the cross section of the particle 47 is the maximum dimension of the particle 47. By measuring the maximum dimension of the particle 47 in this manner, the maximum dimension of the particle 47 contained in the matte layer 40 can be easily measured. Note that, depending on the position of the cross section of the particle 47, the maximum dimension of the particle 47 measured as described above may differ from the true maximum dimension of the particle 47. However, the maximum dimension of the particle 47 measured as described above will not be larger than the true maximum dimension of the particle 47. Therefore, it can be assumed that the true maximum dimension of the particle 47 is equal to or larger than the maximum dimension of the particle 47 measured as described above.
[0076] The content of the particles 47 may be 0.5 parts by mass or more relative to 100 parts by mass of the resin forming the resin layer 41. Preferably, the content of the particles 47 may be 0.75 parts by mass or more. More preferably, the content of the particles 47 may be 1.0 parts by mass or more. More preferably, the content of the particles 47 may be 1.2 parts by mass or more. The content of the particles 47 may be 25.0 parts by mass or less relative to 100 parts by mass of the resin forming the resin layer 41. Preferably, the content of the particles 47 may be 15.0 parts by mass or less. More preferably, the content of the particles 47 may be 10.0 parts by mass or less. More preferably, the content of the particles 47 may be 7.5 parts by mass or less. More preferably, the content of the particles 47 may be 6.0 parts by mass or less.
[0077] Next, an example of a method for manufacturing the laminate 20 of this embodiment will be described with reference to Figs. 3 to 6. First, the base layer 30 is prepared (see Fig. 3). At this stage, the base layer 30 may be laminated with the support material 12, the design layer 50, and the adhesive layer 58. Next, a recess 32 is formed in the base layer 30 (see Fig. 4). The recess 32 may be formed, for example, by embossing the base layer 30 via the first surface 30a.
[0078] Next, a mixture of a resin composition and particles 47 that will later become the resin layer 41 is placed on the first surface 30a of the base layer 30 (see FIG. 5). The mixture is placed over the entire first region A1 and the second region A2. As a result, the mixture is placed so as to fill the recesses 32. The mixture is placed so as to fill the recesses 32 means that the mixture completely fills the recesses 32. That is, the upper surface of the mixture in the first region A1 is located higher than the first surface 30a of the base layer 30 in the second region A2. The mixture may be applied on the first surface 30a in a fluid state, for example. The mixture may be applied by, for example, gravure printing, bar coating, roll coating, reverse roll coating, comma coating, or the like. In this embodiment, the surface of the mixture in the first region A1 is approximately the same height as the surface of the mixture in the second region A2.
[0079] Next, the resin composition is irradiated with light having a wavelength of more than 380 nm to pre-cure the entire resin composition. Preferably, the wavelength of this light may be 385 nm or more and 400 nm or less. Note that this pre-cure step is not essential and may be omitted.
[0080] Thereafter, the surface of the resin composition is irradiated with light having a wavelength of 100 nm or more and 380 nm or less. As a result, wrinkle structure 45 is formed on the surface of the resin composition (see FIG. 6). It is speculated that the mechanism by which this wrinkle structure 45 is formed is as follows. When light having a wavelength of 100 nm or more and 380 nm or less is irradiated on the surface of the resin composition, the light energy penetrates only the surface portion because the wavelength of this light is short, and the light energy does not reach the lower layer. At this time, only the surface portion of the resin composition begins to harden. As a result, only the surface undergoes hardening shrinkage, and wrinkle structure 45 is formed on the surface of the resin composition. It is considered that only the portion of the resin composition within a certain thickness range from the surface is formed in a hardened state. In addition, at this time, it is considered that particle 47 has a function like a nucleus that triggers the formation of wrinkle structure 45. Therefore, it is speculated that the resin on the surface portion of the resin composition gathers around particle 47, and the convex and concave portions of wrinkle structure 45 are formed.
[0081] As the light having a wavelength of 100 nm or more and 380 nm or less, for example, rare gases such as Ar, Kr, Xe, Ne, halides of rare gases such as halogens such as F, Cl, I, Br, or the like, or excited dimers formed by discharging these mixed gases, that is, "excimer light" including light in the ultraviolet wavelength region from excimers may be used. The wavelength of the excimer light and the excimer as the light source may be, for example, light with a wavelength of 126 nm radiated from the excimer of Ar2 (hereinafter abbreviated as "126 nm (Ar2)"), 146 nm (Kr2), 157 nm (F2), 172 nm (Xe2), 193 nm (ArF), 222 nm (KrCl), 247 nm (KrF), 308 nm (XeCl), 351 nm (XeF), etc. As the excimer light, either spontaneous emission light or laser light with high coherence due to stimulated emission may be used. Discharge lamps that emit such light are also called "excimer lamps." Excimer light has a single wavelength peak, and its half-width is narrower than that of normal ultraviolet light (e.g., ultraviolet light emitted from metal halide lamps, mercury lamps, etc.). By using such excimer light, wrinkle formation is stabilized, and the matte effect is improved stably.
[0082] The wavelength of the light irradiated onto the surface of the resin composition may be 120 nm or more. Preferably, the wavelength of the light may be 140 nm or more. More preferably, the wavelength of the light may be 150 nm or more. More preferably, the wavelength of the light may be 155 nm or more. The wavelength of the light irradiated onto the surface of the resin composition may be 320 nm or less. Preferably, the wavelength of the light may be 300 nm or less. More preferably, the wavelength of the light may be 250 nm or less. More preferably, the wavelength of the light may be 200 nm or less. More preferably, the wavelength of the light may be 172 nm (Xe2).
[0083] The cumulative exposure dose of light irradiated onto the surface of the resin composition is 1 mJ / cm 2 Preferably, the integrated exposure dose is 10 mJ / cm or more. 2 More preferably, the cumulative exposure dose is 30 mJ / cm2 More preferably, the cumulative exposure dose is 50 mJ / cm 2 The integrated exposure dose of the light irradiated onto the surface of the resin composition may be 1000 mJ / cm or more. 2 Preferably, the cumulative exposure dose is 500 mJ / cm2 or less. 2 More preferably, the cumulative exposure dose is 300 mJ / cm 2 It may be the following.
[0084] The power density of the light irradiated onto the surface of the resin composition may be 0.001 W / cm or more. Preferably, the power density may be 0.01 W / cm or more. More preferably, the power density may be 0.03 W / cm or more. The power density of the light irradiated onto the surface of the resin composition may be 10 W / cm or less. Preferably, the power density may be 5 W / cm or less. More preferably, the power density may be 3 W / cm or less.
[0085] The oxygen concentration when the surface of the resin composition is irradiated with light may be 1000 ppm or less. Preferably, the oxygen concentration may be 750 ppm or less. More preferably, the oxygen concentration may be 500 ppm or less. More preferably, the oxygen concentration may be 300 ppm or less.
[0086] As described above, the surface of the resin composition is irradiated with light having a wavelength of 100 nm or more and 380 nm or less, and then the resin composition is irradiated with light having a wavelength longer than the wavelength of the light. This causes the curing to proceed in the portion of the resin composition that is far from the surface in the depth direction, and the entire resin composition is cured, forming a resin layer 41 from the resin composition. At this time, the formation of the wrinkle structure 45 proceeds further due to the difference between the degree of curing in the surface portion of the resin composition and the degree of curing in the portion that is far from the surface in the depth direction. For example, ultraviolet light (UV) may be used as the light used to cure the entire resin composition in this way. In addition, other ionizing radiation, such as an electron beam (EB), may be used instead of ultraviolet light when curing the entire resin composition.
[0087] In this case, the appearance of the wrinkle structure 45 in the first region A1 and the appearance of the wrinkle structure 45 in the second region A2 are different from each other in a plan view. In particular, when an observer observes the laminate 20, the degree of matte finish of the first surfaces 20a, 40a in the first region A1 and the degree of matte finish of the first surfaces 20a, 40a in the second region A2 are visually recognized as being different from each other.
[0088] The present inventors speculate as follows about the mechanism by which the wrinkle structure 45 in the first region A1 and the wrinkle structure 45 in the second region A2 have different appearances. The matte layer 40 has a relatively small thickness in the second region A2. Therefore, in the second region A2, a relatively large number of particles 47 are present near the first surfaces 20a, 40a. On the other hand, the matte layer 40 has a relatively large thickness in the first region A1. In the first region A1, the particles 47 sink to the bottom of the recesses 32 due to the action of gravity, so that the number of particles present near the first surfaces 20a, 40a decreases.
[0089] When the surface of the resin composition is irradiated with light having a wavelength of 100 nm or more and 380 nm or less, wrinkle structures 45 are formed in the first region A1 and the second region A2 as follows. In the second region A2, there are many particles 47 present near the first surfaces 20a, 40a. As a result, many fine wrinkle structures 45 are formed on the first surfaces 20a, 40a in the second region A2. In the first region A1, there are few particles 47 present near the first surfaces 20a, 40a. As a result, few wrinkle structures 45 are formed on the first surfaces 20a, 40a in the first region A1. When many fine wrinkle structures 45 are formed on the first surfaces 20a, 40a in the second region A2, the surface layer of the second region A2 pulls the surface layer of the adjacent first region A1. For example, when the recesses 32 of the base layer 30 extend linearly, the surface layer of the first region A1 overlapping with the recesses 32 in a plan view is pulled in the width direction of the recesses 32. As a result, in the first region A1, the wrinkle structure 45 includes many protrusions extending in the width direction of the recess 32 and many recesses extending in the width direction of the recess 32.
[0090] Fig. 7 is a cross-sectional view showing another example of a decorative material 10 including a laminate 20. In the example shown in Fig. 7, the recess 32 of the base layer 30 has a bottom surface formed with a smooth curve.
[0091] 7, the depth D32 of the recess 32 may be 5 μm or more and 100 μm or less. Preferably, the depth D32 may be 10 μm or more and 80 μm or less. More preferably, the depth D32 may be 20 μm or more and 60 μm or less.
[0092] The width W32 of the recess 32 may be 10 μm or more and 500 μm or less. Preferably, the width W32 may be 50 μm or more and 400 μm or less. More preferably, the width W32 may be 100 μm or more and 300 μm or less. The depth D32 and width W32 of the recess 32 are measured in the same manner as the depth D32 and width W32 in the example shown in FIG. 1.
[0093] FIG. 8 is a plan view showing an example of the wrinkle structure 45 of the laminate 20 of FIG. 7. In the example shown in FIG. 8, the recess 32 extends along the vertical direction. Therefore, the vertical direction in FIG. 8 is the extension direction of the recess 32, and the horizontal direction is the width direction of the recess 32. In the example shown in FIG. 8, in the second region A2, the wrinkle structure 45 of the first surface 20a, 40a includes isotropic and fine wrinkle-like unevenness as a whole. In contrast, in the first region A1, the wrinkle structure 45 of the first surface 20a, 40a includes many protrusions extending in the width direction of the recess 32 and many recesses extending in the width direction of the recess 32. As a result, the appearance of the wrinkle structure 45 of the first region A1 and the appearance of the wrinkle structure 45 of the second region A2 are different from each other in a plan view. As a result, when an observer observes the laminate 20, the degree of mattness of the first surfaces 20a, 40a in the first region A1 and the degree of mattness of the first surfaces 20a, 40a in the second region A2 are visually recognized as being different from each other. This difference in appearance can be evaluated by the difference in the average length RSm of the first surfaces 20a, 40a, in the same manner as in the example shown in FIG.
[0094] As shown in Fig. 9, the decorative material 10 may have a molded resin part 14 instead of the support material 12. In this case, the decorative material 10 includes a laminate 20 and a molded resin part 14 laminated with the laminate 20. The molded resin part 14 is a resin member molded into a desired shape. The molded resin part 14 is, for example, an automobile interior part, an automobile exterior part, a resin sash, a handrail, or a home appliance.
[0095] The wrinkle structure 45 formed on the first surface 20a of the laminate 20 may be transferred to the surface of another member. A method for transferring the wrinkle structure 45 using the laminate 20 will be described with reference to Figs.
[0096] First, as shown in FIG. 10, the laminate 20 is prepared. The laminate 20 can be manufactured by the manufacturing method for the laminate 20 described with reference to FIGS. 3 to 6. Next, an uncured resin layer is formed on the first surface 20a of the laminate 20. The resin layer may be formed by applying a resin having fluidity onto the first surface 20a. An ionizing radiation curable resin is used as the resin constituting the resin layer. As the ionizing radiation curable resin, a resin similar to the ionizing radiation curable resin constituting the resin layer 41 may be used.
[0097] An adhesive layer 67, a design layer 70, and a support material 65 may be laminated on the resin layer. The design layer 70 may include a colored layer 72 and a pattern layer 74. The design layer 70 may be formed in the same manner as the design layer 50 in the example described with reference to FIG. 1. The colored layer 72 and the pattern layer 74 may be formed in the same manner as the colored layer 52 and the pattern layer 54 in the example described with reference to FIG. 1. The support material 65 may be formed in the same manner as the support material 12 in the example described with reference to FIG. 1. The adhesive layer 67 may be formed in the same manner as the adhesive layer 58 in the example described with reference to FIG. 1.
[0098] Thereafter, the resin layer is irradiated with ionizing radiation to harden the resin layer, and a hardened resin layer 62 is formed from the resin layer (see FIG. 11). As the ionizing radiation, ultraviolet rays (UV), electron beams (EB), X-rays, gamma rays, or other electromagnetic waves, alpha rays, ion beams, or other charged particle beams may be used.
[0099] FIG. 11 is a cross-sectional view showing an example of a transfer sheet 60 having a laminate 20. The wrinkle structure 45 of the first surface 20a is transferred to the surface of the cured resin layer 62 that contacts the first surface 20a of the laminate 20. As a result, the surface of the cured resin layer 62 that contacts the first surface 20a has a wrinkle structure having a shape in which the uneven shape of the wrinkle structure 45 of the first surface 20a is inverted in the normal direction of the transfer sheet 60. As a result, the transfer sheet 60 shown in FIG. 11 includes the laminate 20 and a cured resin layer 62 containing a cured product of an ionizing radiation curable resin, and the cured resin layer 62 has a wrinkle structure in contact with the first surface 20a of the laminate 20. In the example shown in FIG. 11, the transfer sheet 60 further includes a pattern layer 74 having a pattern, and the cured resin layer 62 is located between the pattern layer 74 and the laminate 20.
[0100] Next, the cured resin layer 62 is peeled off from the laminate 20 (see FIG. 12). This results in a matte sheet 80 including the cured resin layer 62 having a wrinkled structure on its surface. In the example shown in FIG. 12, the matte sheet 80 further includes a support material 65, a design layer 70, and an adhesive layer 67.
[0101] An example of an experiment carried out by the present inventors will be described below. Note that the embodiment of the present disclosure is not limited to the results of the experiment.
[0102] A laminate having a base layer and a matte layer was prepared as follows.
[0103] A base layer was formed by laminating polypropylene resin sheets by extrusion lamination, and the thickness of the base layer was 80 μm.
[0104] In Examples 1 to 3 and Comparative Examples 1 to 3, after forming recesses on the first surface of the base layer by embossing, a matte layer was formed on the first surface. In Comparative Example 4, after forming a matte layer on the first surface of the base layer, surface recesses and recesses were formed on the matte layer by embossing. In the embossing, the base layer was first heated and softened by a non-contact infrared heater. Then, the base layer was embossed by heat and pressure to form a concave-convex pattern.
[0105] The following materials were mixed to obtain a composition containing a resin layer and particles. <Resin layer> Multifunctional urethane acrylate oligomer 30 parts by weight Polyfunctional acrylate monomer 50 parts by weight Monofunctional acrylate monomer 20 parts by weight Photopolymerization initiator (benzophenone type) 2.0 parts by weight <Particle> Silica particles (average particle size 8 μm) 3 parts by weight
[0106] The above composition was applied onto the base layer from the convex side by gravure coating. The dry coating amount in the second region A2 was 15 g / m 2 The coating layer was then irradiated with ultraviolet light to pre-cure the coating layer. For the pre-cure, a UV irradiation device consisting of LEDs was used. The ultraviolet light irradiation conditions for the pre-cure were a wavelength of 395 nm and a maximum illuminance of 0.6 W / cm. 2 , cumulative light intensity 30mJ / cm 2 ~100mJ / cm 2 Next, the coating layer was irradiated with ultraviolet light in a nitrogen atmosphere with an oxygen concentration of 200 ppm or less using an excimer light irradiation device. At this time, a wrinkled structure was formed on the surface of the coating layer. The ultraviolet light irradiation conditions using the excimer light irradiation device were a wavelength of 172 nm (Xe2) and an ultraviolet light output density of 30 mW / cm. 2 , cumulative light intensity 5mJ / cm 2 ~100mJ / cm 2Furthermore, a matte layer was formed by irradiating with an electron beam in a nitrogen atmosphere with an oxygen concentration of 100 ppm or less. The conditions for irradiating with the electron beam were an acceleration voltage of 100 kV to 150 kV and an exposure dose of 30 kGy to 100 kGy. The thickness of the matte layer in the second region A2 was 15 μm. The thickness of the matte layer in the first region A1 changed depending on the shape (width, depth) of the recesses in the base layer.
[0107] Table 1 shows a summary of the shape of the recesses in the base layer, the values of the parameters on the surface (first surface) of the matte layer, and the value and evaluation of the height difference between the first and second regions in each of the examples and comparative examples.
[0108] In Table 1, the "depth (μm)" and "width (μm)" of the "recess shape" of the "base layer" correspond to the depth D32 and width W32 of the recess in the base layer, respectively. In the "recess formation process" column of the "base layer", "A" indicates that a recess was formed on the first surface of the base layer by embossing, and then a matte layer was formed on the first surface. In the same column, "B" indicates that a matte layer was formed on the first surface of the base layer, and then a surface recess and a recess were formed on the matte layer by embossing.
[0109] The "RSm value (μm)" of the "matte layer" indicates the RSm value (μm) of each of the regions A1 and A2 that gives the maximum value of RSm1 / RSm2 or the maximum value of RSm2 / RSm1.
[0110] "Rz (μm)" of the "matte layer" indicates the value of the maximum height Rz in each of the regions A1 and A2. The maximum height Rz is one of the peak and height parameters of the profile curve. In particular, the maximum height Rz is the sum of the height of the highest peak and the depth of the deepest valley in the profile curve in the reference length. The larger the maximum height Rz value, the more valleys with a greater depth when viewed from the peak of the peak exist, and the more such valleys there tend to exist.
[0111] "Ra (μm)" of the "matte layer" indicates the value of the arithmetic mean roughness Ra in each of the regions A1 and A2. The arithmetic mean roughness Ra is one of the parameters in the height direction of the contour curve. In particular, the arithmetic mean roughness Ra is the average value of the height difference from the average plane in the contour curve over the reference length. The smaller the value of the arithmetic mean roughness Ra, the smaller the convex parts in the surface shape and the corresponding concave parts will be, resulting in a smoother and more uniform shape.
[0112] The maximum height Rz and the arithmetic mean roughness Ra were measured using a laser microscope manufactured by Keyence Corporation (model number: VK-X100) in accordance with JIS B0601:2013.
[0113] The "height difference (μm) between the first and second regions of the matte layer" corresponds to the difference in height of the surface (first surface) of the matte layer between the first and second regions. This "height difference (μm) between the first and second regions" is measured by the method for measuring the height difference between the first region A1 and the second region A2 on the first surface 40a of the matte layer 40 described above.
[0114] The design evaluation was performed by 20 adult evaluators visually inspecting the laminates of the articles obtained in the Examples and Comparative Examples. The evaluation was performed by visually inspecting the laminates from a distance of 50 cm under a light source with an illuminance of 700 lux. In the "Design" column of "Evaluation", an evaluation of "A" indicates that 16 or more evaluators (80%) out of the 20 evaluators judged that the matte effect in the plane was not uniform and that a three-dimensional design was obtained. An evaluation of "B" indicates that 15 or fewer evaluators out of the 20 evaluators judged that the matte effect in the plane was not uniform and that a three-dimensional design was obtained.
[0115] The evaluation of the texture was carried out by 20 adult evaluators by touching the surface (first side) of the laminate for the articles obtained in the examples and comparative examples. In the evaluation, Oxford fabric using 80-count cotton yarn was used as the standard for smooth texture. In the "Texture" column of "Evaluation", the evaluation "A" indicates that 16 or more evaluators (80%) out of the 20 evaluators uniformly evaluated the texture as being close to the standard and that they did not feel any unevenness. The evaluation "B" indicates that 15 or fewer evaluators out of the 20 evaluators uniformly evaluated the texture as being close to the standard and that they did not feel any unevenness.
[0116] [Table 1]
[0117] In Examples 1 to 3, the "maximum value of RSm1 / RSm2" and the "maximum value of RSm2 / RSm1" were 1.5 or more. In Examples 1 to 3, the evaluations of both "design" and "touch" were "A". That is, in Examples 1 to 3, when the laminate was visually observed from a distance of 50 cm under a light source with an illuminance of 700 LUX, the first region A1 and the second region A2 on the surface (first surface) of the matte layer were distinguishable from each other. That is, the first region A1 and the second region A2 were given different appearances from each other. In addition, a smooth touch was obtained on the surface of the matte layer as a whole.
[0118] In Comparative Example 1, the "height difference between the first region and the second region" was 10 μm. In Comparative Examples 2 and 3, the "maximum value of RSm1 / RSm2" and the "maximum value of RSm2 / RSm1" were both 0.98 to 1.02, which were smaller than 1.5. In Comparative Example 4, the wrinkle structure in the first region A1 where the surface recesses were located was damaged. As described above, in Comparative Example 4, after a matte layer was formed on the first surface of the base layer, a surface recess was formed from the matte layer by embossing. As a result, in the first region A1, it is considered that the wrinkle structure of the matte layer formed earlier was crushed during embossing. In Comparative Example 4, the wrinkle structure was damaged, so that the value of RSm (RSm1) in the first region A1 could not be measured. Therefore, in Comparative Example 4, the "maximum value of RSm1 / RSm2" and the "maximum value of RSm2 / RSm1" could not be calculated. In Comparative Example 4, the value of the maximum height Rz and the value of the arithmetic mean roughness Ra in the first region A1 could not be measured.
[0119] In Comparative Examples 2 and 3, the evaluation of "design" was "B". That is, in Comparative Examples 2 and 3, when the laminate was visually observed from a distance of 50 cm under a light source with an illuminance of 700 LUX, the first region A1 and the second region A2 on the surface of the matte layer could not be distinguished from each other. The inventor of the present invention speculates that the reason for this is as follows. In Comparative Examples 2 and 3, the "maximum value of RSm1 / RSm2" and the "maximum value of RSm1 / RSm2" are close to 1. As a result, the evaluator was unable to visually recognize the difference between the gloss of the first region A1 and the gloss of the second region A2. That is, it is considered that the evaluator did not feel a three-dimensional effect.
[0120] In Comparative Examples 1 to 4, the evaluation of "touch" was "B". That is, in Comparative Examples 1 to 4, an overall smooth touch was not obtained. The present inventor speculates that the reason for this is as follows. In Comparative Examples 1 to 4, the "height difference between the first region and the second region" is 10 μm or more. It is considered that this is why the evaluator perceived an uneven touch when touching the surface of the laminate.
[0121] From the results in Table 1, it can be confirmed that when the "maximum value of RSm1 / RSm2" or the "maximum value of RSm2 / RSm1" is both 1.5 or more, it is possible to impart different appearances to the first region A1 and the second region A2 on the surface of the matte layer, and also to obtain an overall smooth feel. [Explanation of symbols]
[0122] 10 Cosmetic materials 12 Support material 14 Molded resin part 20 Laminate 20a Page 1 20b 2nd side 30 Base Layer 32 Recess 40 Matte Layer 41 Resin layer 45 Wrinkle structure 47 particles 50 Design Layer 52 Colored layer 54 Picture layer 58 Adhesive layer 60 Transfer Sheet 80 Matte Sheet A1 1st area A2 2nd area
Claims
1. A laminate having a matte layer having a wrinkled structure on a surface thereof, The matte layer includes a first region and a second region having different thicknesses, When the value of the average length RSm in the first region as specified in JIS B0601:2013 is RSm1 and the value of the average length RSm in the second region as specified in JIS B0601:2013 is RSm2, A laminate, wherein the maximum value of the ratio of RSm1 to RSm2 (RSm1 / RSm2) or the maximum value of the ratio of RSm2 to RSm1 (RSm2 / RSm1) is 1.5 or more.
2. A laminate having a matte layer having a wrinkled structure on a surface thereof, The matte layer includes a first region and a second region having different thicknesses, A laminate, wherein the degree of mattness of the surface in the first region and the degree of mattness of the surface in the second region are visually perceived to be different from each other.
3. A laminated ... the base layer has a recess on a surface facing the matte layer; The laminate according to claim 1 or 2, wherein the first region of the matte layer is a region that overlaps with the recess in a planar view, and the second region is a region that does not overlap with the recess in a planar view.
4. The laminate according to claim 1 or 2, wherein a height difference between the first region and the second region is less than 10 μm.
5. Further comprising a pattern layer having a pattern, The laminate according to claim 1 , wherein the first region and the second region are arranged according to the pattern.
6. The laminate according to claim 1 or 2, A decorative material comprising the laminate and a support material laminated thereto.
7. 7. The decorative material of claim 6, wherein the support material is a building material.
8. The laminate according to claim 1 or 2, A decorative material comprising the laminate and a molded resin part laminated therewith.
9. The laminate according to claim 1 or 2, a cured resin layer including a cured product of an ionizing radiation curable resin; The cured resin layer has a wrinkled structure in contact with the first surface of the transfer sheet.
10. Further comprising a pattern layer having a pattern, The transfer sheet according to claim 9 , wherein the cured resin layer is located between the design layer and the laminate.
11. 1. A method for producing a laminate comprising: a base layer having a first surface with a recess; and a matte layer disposed opposite the first surface, the method comprising the steps of: laminating a resin layer on the base layer so as to fill the recess; and forming the matte layer from the resin layer by irradiating the resin layer with light having a wavelength of 100 nm or more and 380 nm or less.
Citation Information
Patent Citations
Decorative sheet and method for producing the same
JP2021024102A