Winding body and method for manufacturing a winding body

Abstract

The present invention provides a winding body and a method for manufacturing a winding body that can suppress winding misalignment and reduce marks on the surface of the laminated film. [Solution] A laminated film 2 comprising a resin film 21 having voids 211 is wound around the wound body 1. Furthermore, the durometer hardness A measured from the outermost radial surface of the wound body 1 is 84.1 or higher and 94.5 or lower.

Description

Technical Field

[0001] The present invention relates to a wound body and a method for manufacturing a wound body.

Background Art

[0002] Conventionally, a wound body in which a laminated film including a resin film is wound around a core is known. As the resin film used for such a wound body, a transparent resin film can be mentioned (for example, see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] On the other hand, when using a resin film having voids (specifically, a white resin film) as the resin film, compared with the case of using the transparent resin film described in Patent Document 1, when forming a wound body, the surface of the laminated film is likely to be scratched.

[0005] In addition, if the tension for winding the laminated film is adjusted so that the surface of the laminated film is not scratched, there is a possibility of winding deviation.

[0006] An object of the present invention is to provide a wound body and a method for manufacturing a wound body that can suppress winding deviation and reduce scratches on the surface of the laminated film.

Means for Solving the Problems

[0007] The present invention [1] includes a winding of a laminated film comprising a resin film, wherein the resin film has voids and the durometer hardness A, measured from the radial outermost surface of the winding, is 84.1 or greater and 94.5 or less.

[0008] The present invention [2] includes the winding body described in [1] above, wherein the total light transmittance of the resin film is less than 50%.

[0009] The present invention [3] comprises a winding body according to [1] or [2] above, wherein the resin film contains particles.

[0010] The present invention [4] includes a winding body according to any one of the above [1] to [3], wherein the laminated film further comprises a metallic reflective layer.

[0011] The present invention [5] is a method for manufacturing a wound body according to any one of [1] to [4] above, comprising the step of winding the laminated film. [Effects of the Invention]

[0012] The winding body of the present invention has a durometer hardness A measured from the outermost radial surface, which is between 84.1 and 94.5. Therefore, even in a winding body of a laminated film comprising a resin film having voids, winding misalignment can be suppressed and traces on the laminated film surface can be reduced.

[0013] Furthermore, the present invention provides a method for manufacturing a wound body, comprising the step of winding a laminated film. Therefore, it is possible to manufacture a wound body that suppresses winding misalignment and reduces marks on the surface of the laminated film. [Brief explanation of the drawing]

[0014] [Figure 1] Figures 1A and 1B show one embodiment of the wound body of the present invention, where Figure 1A is a perspective view and Figure 1B is a side view. [Figure 2]FIG. 2 shows a cross-sectional view of the laminated film forming the wound body shown in FIG. 1 and an enlarged view of the resin film included in the laminated film.

BEST MODE FOR CARRYING OUT THE INVENTION

[0015] 1. Wound body Referring to FIGS. 1 and 2, an embodiment of the wound body 1 of the present invention will be described.

[0016] FIG. 1 shows a wound body 1 of a laminated film 2 including a resin film 21. Specifically, in the wound body 1 of FIG. 1, the laminated film 2 including the resin film 21 is wound around a plurality of turns.

[0017] The wound body 1 includes, for example, a laminated film 2 including a resin film 21 and a core 3 around which the laminated film 2 is wound. Further, the wound body 1 may further include an adhesive member (not shown) as necessary.

[0018] 1.1. Laminated film The laminated film 2 extends in a plane direction orthogonal to the thickness direction. Further, the laminated film 2 is a film that is long in one direction (longitudinal direction) in the plane direction and short in a direction (lateral direction) orthogonal to the longitudinal direction. In the following, the lateral direction may sometimes be referred to as the width direction.

[0019] The laminated film 2 is not particularly limited as long as it includes a resin film 21 described later. In the present embodiment, the laminated film 2 is a reflective film including a resin film 21 and a metal reflective layer 22. The reflective film is used, for example, to suppress light from the backlight of a liquid crystal display device from leaking out of the housing.

[0020] As shown in FIG. 2, the laminated film 2 includes, for example, a resin film 21, a metal reflective layer 22 disposed on one surface in the thickness direction of the resin film 21, an inorganic blackening layer 23 disposed on one surface in the thickness direction of the metal reflective layer 22, and a cured resin layer 24 disposed on one surface in the thickness direction of the inorganic blackening layer 23.

[0021] [Resin Film] The resin film 21 supports other layers (for example, the metal reflection layer 22, the inorganic blackening layer 23, and the cured resin layer 24 described later) in the laminated film 2. The resin film 21 has a thickness and has a film shape (including a sheet shape) that spreads in the plane direction orthogonal to the thickness direction. Also, the resin film 21 has flexibility.

[0022] Examples of the material of the resin film 21 include polyester resin, polyolefin resin, acrylic resin, polycarbonate resin, polyethersulfone resin, polyarylate resin, melamine resin, polyamide resin, polyimide resin, cellulose resin, and polystyrene resin. Examples of the polyester resin include polyethylene terephthalate (PET), polybutylene terephthalate, and polyethylene naphthalate. Examples of the polyolefin resin include polyethylene, polypropylene, and cycloolefin polymer. Examples of the acrylic resin include polymethacrylate. Examples of the cellulose resin include triacetyl cellulose. From the viewpoints of heat resistance, mechanical strength, etc., the resin film 21 is preferably a polyester resin film. More preferably, it is a PET film.

[0023] The resin film 21 has voids 211. If the resin film 21 has voids 211, light scattering occurs and the light reflectivity can be improved.

[0024] The cross-sectional shape of the voids 211 is not particularly limited, and examples include a substantially circular shape and a substantially elliptical shape. Also, the maximum length of the voids 211 (the diameter when the cross-sectional shape of the voids 211 is a substantially circular shape) is, for example, 0.01 μm or more, preferably 0.1 μm or more, and also, for example, 10 μm or less, preferably 5 μm or less.

[0025] The area ratio of the voids 211 in the cross-section of the resin film 21 is, for example, 1% or more, 5% or more, and also, for example, 50% or less, preferably 20% or less.

[0026] The maximum length of the void 211 and the area ratio of the void 211 can be determined by analyzing images of the cross-section of the resin film 21 obtained by transmission electron microscopy (TEM).

[0027] Furthermore, the resin film 21 may contain, for example, particles 212. If the resin film 21 contains particles 212, light scattering will occur even more, improving light reflectivity. However, the resin film 21 does not necessarily have to contain particles 212.

[0028] Examples of particles 212 in the resin film 21 include inorganic particles. Examples of materials for the inorganic particles include titanium dioxide, calcium carbonate, barium sulfate, silica, and talc. Titanium dioxide is preferred. In other words, the particles 212 in the resin film 21 are preferably titanium dioxide particles. Furthermore, the particles 212 may consist of a single type of particle, or two or more types of particles may be used in combination.

[0029] The shape of the particles 212 in the resin film 21 can be, for example, approximately spherical. The average particle diameter (D50) of the particles 212 in the resin film 21 is, for example, 0.05 μm or more, preferably 0.1 μm or more, and also, for example, 2 μm or less, preferably 1 μm or less. The average particle diameter (D50) of the particles in the resin film 21 is the median diameter (particle size at which the volume cumulative frequency from the smallest diameter side reaches 50%) in the volume-based particle size distribution, and can be determined, for example, based on the particle size distribution obtained by the laser diffraction-scattering method.

[0030] If the resin film 21 contains particles 212, the content of particles 212 in the resin film 21 is, for example, 5% by volume or more, preferably 10% by volume or more, and for example, 50% by volume or less, preferably 40% by volume or less.

[0031] The proportion of particles 212 in the resin film 21 can be determined by analyzing images of the cross-section of the resin film 21 obtained using a transmission electron microscope (TEM).

[0032] The resin film 21 having the voids 211 and / or particles 212 described above is a white resin film. In other words, the resin film 21 is preferably a white PET film.

[0033] The total light transmittance of the resin film 21 is, for example, less than 50%, preferably 40% or less, more preferably 30% or less, even more preferably 20% or less, and also, for example, 1% or more.

[0034] The total light transmittance of the resin film 21 can be calculated by measuring the spectrum in the wavelength range of 380 nm to 780 nm using a spectrophotometer (U4100, manufactured by Hitachi High-Tech Science Corporation).

[0035] Compared to a transparent resin film (for example, a resin film with a total light transmittance of 80% or more), a resin film 21 (white resin film) having the total light transmittance within the above range is more prone to developing marks on the surface of the laminated film 2 when a wound body is formed.

[0036] The thickness of the resin film 21 is, for example, 5 μm or more, preferably 10 μm or more, and more preferably 20 μm or more, from the viewpoint of the mechanical strength of the laminated film 2, and from the viewpoint of ease of handling, for example, 300 μm or less, preferably 150 μm or less, and more preferably 100 μm or less.

[0037] The thickness of the resin film 21 can be measured, for example, using a film thickness gauge.

[0038] One side of the resin film 21 in the thickness direction (the side on which the metal reflective layer 22 is placed) may be surface-modified to improve the adhesion between the resin film 21 and the metal reflective layer 22. Examples of surface modification treatments include corona treatment, plasma treatment, ozone treatment, primer treatment, glow treatment, and coupling agent treatment.

[0039] [Metal reflective layer] The metal reflective layer 22 is positioned on one side of the resin film 21 in the thickness direction. That is, the metal reflective layer 22 is in contact with one side of the resin film 21 in the thickness direction.

[0040] The metal reflective layer 22 is formed from a metal that has light reflectivity. Examples of metals that form the metal reflective layer 22 include aluminum (Al), silver (Ag), titanium (Ti), and alloys thereof. From the viewpoint of improving the light reflectivity of the metal reflective layer 22 for visible light, aluminum and silver are preferably used as the metals that form the metal reflective layer 22. That is, the metal reflective layer 22 is preferably an aluminum layer and a silver layer.

[0041] The thickness of the metal reflective layer 22 is, for example, 10 nm or more, preferably 30 nm or more, and more preferably 50 nm or more, from the viewpoint of improving the light reflectivity of the metal reflective layer 22, and from the viewpoint of improving the adhesion of the metal reflective layer 22 to the resin film 21, it is, for example, 500 nm or less, preferably 300 nm or less, and more preferably 200 nm.

[0042] [Inorganic Blackening Layer] The inorganic blackening layer 23 is positioned on one side in the thickness direction of the metal reflective layer 22. That is, the inorganic blackening layer 23 is in contact with one side in the thickness direction of the metal reflective layer 22.

[0043] The inorganic blackening layer 23 is an inorganic layer with high light absorption. The inorganic blackening layer 23 includes, for example, a metal compound and an elemental metal. Preferably, it consists of a metal compound and an elemental metal. The inorganic blackening layer 23 may contain multiple metal compounds or multiple elemental metals.

[0044] Metallic compounds are compounds of metals and nonmetals. Examples of metallic compounds include metal oxides, metal nitrides, metal carbides, and metal hydroxides. Preferably, metal oxides are used. Examples of metals (first metals) in metallic compounds include indium (In), copper (Cu), molybdenum (Mo), and iron (Fe). Preferably, the first metal includes at least one selected from the group consisting of In, Cu, Mo, and Fe. More preferably, it includes at least one selected from the group consisting of In and Cu. In other words, preferably, metallic compounds include indium oxide and copper oxide. Furthermore, the first metal may be used alone or in combination of two or more types.

[0045] Examples of elemental metals (secondary metals) include In, Cu, Mo, and Fe. Preferably, the secondary metal comprises at least one selected from the group consisting of In, Cu, Mo, and Fe. More preferably, it comprises Cu. Even more preferably, it comprises Cu. Furthermore, the secondary metal may be used alone or in combination of two or more types.

[0046] The first and second metals may be the same or different.

[0047] The proportion of the first metal in the inorganic blackened layer 23 is, for example, 10 atomic% or more, preferably 20 atomic% or more, and also, for example, 90 atomic% or less, preferably 80 atomic% or less, from the viewpoint of achieving high light-shielding properties of the inorganic blackened layer 23. The proportion of the second metal in the inorganic blackened layer 23 is, for example, 10 atomic% or more, preferably 20 atomic% or more, and also, for example, 90 atomic% or less, preferably 80 atomic% or less, from the viewpoint of achieving high light-shielding properties of the inorganic blackened layer 23.

[0048] From the viewpoint of achieving high light-shielding properties of the inorganic blackening layer 23, the inorganic blackening layer 23 is, for example, a layer containing a metal compound and an elemental metal, preferably a layer containing a metal oxide and an elemental metal, and more preferably a layer containing indium oxide and copper.

[0049] The thickness of the inorganic blackening layer 23 is, for example, 5 nm or more, preferably 10 nm or more, and more preferably 20 nm or more, from the viewpoint of improving the light-shielding properties of the inorganic blackening layer 23, and from the viewpoint of improving the adhesion of the inorganic blackening layer 23 to the metal reflective layer 22, it is, for example, 300 nm or less, preferably 150 nm or less, and more preferably 100 nm or less.

[0050] The luminous transmittance (Y value) of the inorganic blackening layer 23 at wavelengths of 380 nm to 780 nm in the CIE-XYZ color system is, for example, 0.1% or less, preferably 0.05% or less, more preferably 0.03% or less, and also, for example, 0.001% or more. The luminous transmittance can be measured, for example, by a spectrophotometer (product name: U-4100, manufactured by Hitachi High-Tech Science Corporation).

[0051] [Cured resin layer] The cured resin layer 24 is positioned on one side in the thickness direction of the inorganic blackening layer 23. That is, the cured resin layer 24 is in contact with one side in the thickness direction of the inorganic blackening layer 23. The cured resin layer 24 is, for example, a hard coat layer (HC layer) to make it difficult for scratches to form on the laminated film 2.

[0052] The cured resin layer 24 is a cured product of a curable resin composition. The curable resin composition contains a curable resin. Examples of curable resins include polyester resin, acrylic urethane resin, acrylic resin (excluding acrylic urethane resin), urethane resin (excluding acrylic urethane resin), amide resin, silicone resin, epoxy resin, and melamine resin. The curable resin may be used alone or in combination of two or more types. From the viewpoint of improving the hardness of the cured resin layer 24, preferably, at least one selected from the group consisting of acrylic urethane resin and acrylic resin is used as the curable resin.

[0053] Examples of curable resins include UV-curable resins and thermosetting resins. UV-curable resins are preferred as curable resins because they can be cured without high-temperature heating, thus improving manufacturing efficiency.

[0054] The curable resin composition may contain particles. In other words, the curable resin layer 24 may contain particles. Examples of particles in the curable resin layer 24 include inorganic oxide particles and organic particles. Examples of materials for inorganic oxide particles include silica, alumina, titania, zirconia, calcium oxide, tin oxide, indium oxide, cadmium oxide, and antimony oxide. Examples of materials for organic particles include polymethyl methacrylate, polystyrene, polyurethane, acrylic-styrene copolymer, benzoguanamine, melamine, and polycarbonate. The particles in the curable resin layer 24 may be used individually or in combination of two or more types.

[0055] Furthermore, the curable resin composition may contain nanoparticles and / or microparticles as particles. In other words, the curable resin layer 24 may contain nanoparticles and / or microparticles as particles. Preferably, the curable resin layer 24 contains nanoparticles and microparticles as particles. Note that each of the nanoparticles and microparticles has an average particle diameter (D50) as described later.

[0056] The average particle size (D50) of nanoparticles in the cured resin layer 24 is, for example, 20 nm or more, preferably 25 nm or more, and more preferably 30 nm or more, from the viewpoint of improving the hardness of the cured resin layer 24, and from the viewpoint of uniform dispersion of particles within the cured resin layer 24, it is, for example, 300 nm or less, preferably 100 nm or less.

[0057] The average particle size (D50) of the microparticles in the cured resin layer 24 is, from the viewpoint of improving the antiblocking properties of the cured resin layer 24, for example, 0.5 μm or more, preferably 1.0 μm or more, more preferably 1.5 μm or more, even more preferably 2.0 μm or more, particularly preferably 2.5 μm or more, or, for example, 10 μm or less, preferably 6.0 μm or less, more preferably 5.0 μm or less, even more preferably 4.0 μm or less, particularly preferably 3.5 μm or less. Note that the average particle size (D50) of the microparticles in the cured resin layer 24 may be greater than the thickness of the cured resin layer 24. Preferably, it is greater than the thickness of the cured resin layer 24.

[0058] The average particle size (D50) of particles (nanoparticles and microparticles) in the cured resin layer 24 is the median diameter (the particle size at which the volume cumulative frequency reaches 50% from the smallest diameter side) in the volume-based particle size distribution, and can be determined, for example, based on the particle size distribution obtained by the laser diffraction-scattering method.

[0059] When the cured resin layer 24 contains nanoparticles, the particle content in the cured resin layer 24 is, for example, 10% by volume or more, preferably 20% by volume or more, from the viewpoint of improving the hardness of the cured resin layer 24, and, from the viewpoint of uniform dispersion of particles within the cured resin layer 24, for example, 90% by volume or less, preferably 80% by volume or less.

[0060] The nanoparticle content in the cured resin layer 24 can be determined by analyzing cross-sectional images of the cured resin layer 24 obtained using a transmission electron microscope (TEM).

[0061] When the cured resin layer 24 contains microparticles, the content of microparticles per 100 parts by mass of curable resin is, for example, 0.1 parts by mass or more, preferably 0.3 parts by mass or more, more preferably 0.6 parts by mass or more, even more preferably 0.8 parts by mass or more, particularly preferably 0.9 parts by mass or more, or, for example, 10 parts by mass or less, preferably 5.0 parts by mass or less, more preferably 3.0 parts by mass or less, even more preferably 1.5 parts by mass or less, particularly preferably 1.2 parts by mass or less.

[0062] The thickness of the cured resin layer 24 is, for example, 0.1 μm or more, preferably 0.5 μm or more, from the viewpoint of improving the abrasion resistance of the cured resin layer 24, and for example, 5 μm or less, preferably 3 μm or less, from the viewpoint of improving the adhesion of the cured resin layer 24 to the inorganic blackening layer 23.

[0063] The laminated film 2 may also include layers other than the metal reflective layer 22, the inorganic blackening layer 23, and the cured resin layer 24 described above. Examples of other layers include a conductive layer (e.g., a metal oxide layer), an antiblocking layer, and an optical adjustment layer.

[0064] The length of the laminated film 2 in the longitudinal direction is not particularly limited. For example, the length of the laminated film 2 in the longitudinal direction may be 50m to 1200m.

[0065] The widthwise length of the laminated film 2 is not particularly limited. For example, the widthwise length of the laminated film 2 is between 100 mm and 4000 mm.

[0066] The thickness of the laminated film 2 is, for example, 5 μm or more, preferably 10 μm or more, more preferably 20 μm or more, and also, for example, 300 μm or less, preferably 150 μm or less, more preferably 100 μm or less.

[0067] The luminous reflectance (Y value) of the laminated film 2 at wavelengths of 380 nm to 780 nm in the CIE-XYZ color system is, for example, 80% or more, preferably 85% or more, and for example, 100% or less. The luminous reflectance (Y value) of the laminated film 2 is defined as the reflectance of light irradiated onto the laminated film 2 from the resin film 21 side (the other side in the thickness direction).

[0068] The luminous transmittance (Y value) of the laminated film 2 at wavelengths of 380 nm to 780 nm in the CIE-XYZ color system is, for example, 0.10% or less, preferably 0.05% or less, and for example, 0.001% or more. The luminous transmittance (Y value) of the laminated film 2 is defined as the transmittance of light irradiated onto the laminated film 2 from the resin film 21 side (the other side in the thickness direction).

[0069] 1.2. Core The core 3 is the core around which the laminated film 2 described above is wound.

[0070] The shape of the core 3 is not particularly limited. From the viewpoint of easily winding the laminated film 2, the shape of the core 3 can be, for example, a cylindrical shape or a cylindrical shape.

[0071] The material of the core 3 is not particularly limited. Examples of materials for the core 3 include polymer materials, paper materials, and metal materials. Polymer materials are preferred.

[0072] Examples of polymer materials for the core 3 include acrylonitrile-butadiene-styrene copolymer (ABS), polyethylene, polypropylene, polyvinyl chloride, polystyrene, ethylene-propylene copolymer, and ethylene-vinyl acetate copolymer. Preferably, ABS is used. In other words, the core 3 is preferably made of ABS.

[0073] Examples of metal materials for the core 3 include iron, stainless steel, and aluminum.

[0074] The radial length of the core 3 is not particularly limited. If the core 3 is cylindrical, the radial length is the average diameter; if it is cylindrical, the radial length is the average outer diameter. The radial length of the core 3 is, for example, 50 mm or more, preferably 100 mm or more, and also, for example, 1000 mm or less, preferably 500 mm or less. In the width direction, the radial length of the core 3 is approximately the same.

[0075] The widthwise length of the core 3 is not particularly limited, and is, for example, greater than or equal to the widthwise length of the laminated film 2. The widthwise length of the core 3 is, for example, 100 mm or more, preferably 200 mm or more, and also, for example, 10,000 mm or less, preferably 8,000 mm or less. Note that the widthwise length of the core 3 is the average widthwise length of the core 3.

[0076] 1.3. Adhesive Members The adhesive member (not shown) attaches one longitudinal end of the laminated film 2 to the outer surface of the core 3. In other words, the winding body 1 has an adhesive member between one longitudinal end of the laminated film 2 and the outer surface of the core 3. Note that the outer surface of the core 3 refers to the radially outer surface.

[0077] Specifically, the longitudinal end of the laminated film 2 is attached to the outer surface of the core 3 by an adhesive member such that the widthwise center of the laminated film 2 and the widthwise center of the core 3 are approximately aligned. Additionally, the longitudinal end of the laminated film 2 is attached to the outer surface of the core 3 by an adhesive member such that the width direction of the laminated film 2 and the width direction of the core 3 are approximately parallel.

[0078] In this embodiment, the laminated film 2 is attached to the outer surface of the core 3 by an adhesive member, such that the cured resin layer 24 side (opposite side of the resin film 21) at one end in the longitudinal direction of the laminated film 2 faces inward.

[0079] The joining member is not particularly limited, as long as it is one that is normally used to bond the laminated film 2 and the core 3 in the formation of the wound body 1. Examples of joining members include adhesives and double-sided tapes. Double-sided tapes are preferred.

[0080] The adhesive and double-sided tape are not particularly limited, as long as they are those commonly used to bond the laminated film 2 and the core 3 in the formation of the wound body 1. The joining members may be used individually or in combination of two or more types.

[0081] The thickness of the joining member is, for example, 1 μm or more, preferably 3 μm or more, and for example, 100 μm or less, preferably 80 μm or less, and more preferably 50 μm or less.

[0082] In the longitudinal direction of the laminated film 2, the length of the joining member is not particularly limited, as long as it is long enough to attach one end of the laminated film 2 in the longitudinal direction to the outer surface of the core 3. For example, it may be 10 mm or more, preferably 30 mm or more, and for example, 500 mm or less, preferably 300 mm or less.

[0083] In the width direction of the laminated film 2, the length of the joining member is not particularly limited, as long as it is long enough to attach one longitudinal end of the laminated film 2 to the outer surface of the winding core 3. In the width direction of the laminated film 2, the length of the joining member may be the same as the length of the laminated film 2, or it may be shorter than the length of the laminated film 2.

[0084] One longitudinal end of the laminated film 2 is attached so as to overlap with one side of the joining member that extends in the width direction. Furthermore, if the width of the joining member is the same as the width of the laminated film 2, the laminated film 2 is attached so as to overlap one side of the joining member that extends in the width direction and both sides that extend in the longitudinal direction.

[0085] 1.4. Details of the coiled body The winding diameter (radial length) of the winding body 1 is, for example, 90 m or more, preferably 100 m or more, and also, for example, 300 m or less, preferably 320 m or less. In this embodiment, the winding diameter (radial length) of the winding body 1 refers to the diameter.

[0086] The number of turns of the laminated film 2 in the wound body 1 is, for example, 10 turns or more, preferably 30 turns or more, and for example, 4500 turns or less, preferably 5000 turns or less.

[0087] The durometer hardness A, measured from the outermost radial surface of the wound body 1, is 84.1 to 94.5, preferably 84.5 to 93.0, more preferably 84.5 to 91.5, even more preferably 85.0 to 90.0, and most preferably 85.0 to 88.0.

[0088] The durometer hardness A measured from the outermost radial surface of the wound body 1 is 84.1 or higher, preferably 84.5 or higher, and more preferably 85.0 or higher. Alternatively, the durometer hardness A measured from the outermost radial surface of the wound body 1 is 94.5 or lower, preferably 93.0 or lower, more preferably 91.5 or lower, even more preferably 90.0 or lower, and particularly preferably 88.0 or lower.

[0089] If the durometer hardness A, measured from the outermost radial surface of the wound body 1, is greater than or equal to the lower limit, winding misalignment can be suppressed. Also, if the durometer hardness A, measured from the outermost radial surface of the wound body 1, is less than or equal to the upper limit, traces on the surface of the laminated film 2 can be reduced. In other words, if the durometer hardness A, measured from the outermost radial surface of the wound body 1, is within the above range, winding misalignment can be suppressed while traces on the surface of the laminated film 2 can be reduced.

[0090] The durometer hardness A is measured in accordance with JIS K6253-1997. Details are provided below regarding the measurement method described in the examples.

[0091] 2. Method for manufacturing laminated film The laminated film 2 is manufactured, for example, by a roll-to-roll method.

[0092] First, a metal reflective layer 22 is formed on one side of the resin film 21 in the thickness direction (metal reflective layer formation step). Specifically, the metal reflective layer 22 is formed by depositing the material for the metal reflective layer 22 onto one side of the resin film 21 in the thickness direction using a dry coating method. Examples of dry coating methods include sputtering and vapor deposition. Sputtering is preferred. In other words, the metal reflective layer 22 is, for example, a dry coated layer, and preferably a sputtered layer.

[0093] In the sputtering method, for example, a sputtering deposition apparatus capable of performing the film deposition process using a roll-to-roll method is used. Specifically, in the sputtering method, a sputtering gas (inert gas) is introduced into the deposition chamber of the sputtering deposition apparatus under vacuum conditions, and a negative voltage is applied to a target placed on the cathode in the deposition chamber. This generates a glow discharge, ionizing the gas atoms, and these gas ions are made to collide with the target surface at high speed, ejecting the target material from the target surface, and depositing the ejected target material on one side in the thickness direction of the resin film 21.

[0094] The material of the target placed on the cathode in the deposition chamber is the same as the material of the metal reflective layer 22 described above.

[0095] The conditions for sputter deposition are as follows:

[0096] Examples of sputtering gases include argon, krypton, xenon, and mixtures thereof. Reactive gases (e.g., oxygen) may also be used in combination. The atmospheric pressure inside the deposition chamber during sputtering (sputter deposition) is, for example, 0.02 Pa to 1 Pa. When reactive gases are used in combination, the partial pressure of the reactive gas inside the deposition chamber is, for example, 1.0 × 10⁻⁶. -4 Pa~1.0×10 -2The pressure is Pa. Examples of power supplies for applying voltage to the target include DC power supplies, AC power supplies, MF power supplies, and RF power supplies. The absolute value of the discharge voltage during sputtering is, for example, 50V to 500V. The deposition temperature during sputtering is, for example, -20 to 100°C.

[0097] The sputtering deposition conditions described above are also adjusted as appropriate within the same range for the sputtering deposition of the inorganic blackening layer 23, which will be described later.

[0098] Next, an inorganic blackening layer 23 is formed on one side of the metal reflective layer 22 in the thickness direction (inorganic blackening layer formation step). Specifically, the inorganic blackening layer 23 is formed by depositing the material for the inorganic blackening layer 23 on one side of the metal reflective layer 22 in the thickness direction using a dry coating method. Examples of dry coating methods include sputtering and vapor deposition, with sputtering being preferred. In other words, the inorganic blackening layer 23 is, for example, a dry coating layer, and preferably a sputtered layer. Note that with the dry coating method (sputtering method), the inorganic blackening layer 23 can be formed thinner than a blackening layer made of organic material (for example, a black ink layer).

[0099] The material of the target placed on the cathode in the sputtering method is the same as the material of the inorganic blackened layer 23 described above.

[0100] In the processes of forming the metal reflective layer and the inorganic blackening layer, the metal reflective layer and the inorganic blackening layer are deposited continuously in a single pass line using a roll-to-roll method. The metal reflective layer and the inorganic blackening layer are deposited in a single pass line under vacuum (reduced pressure). Therefore, the adhesion of the metal reflective layer 22 to the resin film 21 and the adhesion of the inorganic blackening layer 23 to the metal reflective layer 22 can be improved.

[0101] Next, a cured resin layer 24 is formed on one side of the inorganic blackening layer 23 in the thickness direction (cured resin layer formation step). The cured resin layer 24 can be formed by applying the above-mentioned curable resin composition to one side of the inorganic blackening layer 23 in the thickness direction to form a coating film, and then curing this coating film. If the curable resin composition contains an ultraviolet-curable resin, the coating film is cured by ultraviolet irradiation. If the curable resin composition contains a thermosetting resin, the coating film is cured by heating.

[0102] Examples of methods for applying the cured resin layer 24 include roll coating, kiss roll coating, gravure coating, reverse coating, roll brushing, spray coating, dip roll coating, bar coating, knife coating, air knife coating, curtain coating, lip coating, and die coating. Gravure coating is preferred.

[0103] The cured resin layer formation step may be carried out immediately following the inorganic blackening layer formation step described above, or it may be carried out as an independent step.

[0104] In this manner, the laminated film 2 can be manufactured.

[0105] 3. Method for manufacturing a wound body The method for manufacturing the wound body is a method for manufacturing the above-described wound body 1, comprising the step of winding a laminated film 2.

[0106] One embodiment of the method for manufacturing a wound body includes, for example, a step of feeding out the laminated film 2 (feeding step), a step of adjusting the tension applied to the laminated film 2 (tension adjustment step), and a step of winding the laminated film 2 (winding step). The method for manufacturing a wound body may also include a step of cutting the laminated film 2 to a predetermined length in the width direction (cutting step).

[0107] The wound body 1 is manufactured, for example, by a roll-to-roll method. In one embodiment of the manufacturing method of the wound body, it is manufactured by a roll-to-roll method using a slitting machine. The slitting machine comprises, for example, a feed roll, a tension adjustment unit, and a winding roll. Furthermore, when winding the laminated film 2 while cutting it, the slitting machine may also include a cutting unit.

[0108] The feed roll feeds out the laminated film 2. The feed roll is a cylindrical member having a rotation axis. A first drive source is connected to the feed roll for rotating it. The feed roll is rotatable by a predetermined driving force from the first drive source.

[0109] The tension adjustment unit adjusts the tension applied to the laminated film 2. The tension adjustment unit is located between the delivery roll and the winding roll in the transport direction of the laminated film 2. One example of a tension adjustment method in the tension adjustment unit is a method using a dancer roll.

[0110] The winding roll winds up the laminated film 2. The winding roll is the winding core 3 described above. A second drive source is connected to the winding roll for rotating it. The winding roll is rotatable by a predetermined driving force from the second drive source.

[0111] If a cutting section is provided, the laminated film 2 is cut at the cutting section so that it has a predetermined length in the width direction. In other words, the laminated film 2 is cut along the longitudinal direction at the cutting section. The cutting method is not particularly limited.

[0112] In one embodiment of the method for manufacturing a wound body, first, the laminated film 2 is set on the feed roll of the slitting machine described above.

[0113] Next, one end of the laminated film 2 in the longitudinal direction is attached to the winding roll (winding core 3) via an adhesive member. Specifically, at one end of the laminated film 2 in the longitudinal direction, it is attached to the winding roll (winding core 3) via an adhesive member so that the cured resin layer 24 side faces inward.

[0114] Then, the first and second drive sources are driven to rotate the feed roll and the winding roll, thereby transporting the laminated film 2 from the feed roll to the winding roll. Specifically, the laminated film 2 is fed out from the feed roll (feeding process), the tension is adjusted by the tension adjustment unit (tension adjustment process), and then wound up by the winding roll (winding process).

[0115] As a result, the laminated film 2 is transported from the delivery roll to the winding roll using a roll-to-roll method, and the wound body 1 is manufactured.

[0116] The transport speed of the laminated film 2 is, for example, 3 m / min or more, preferably 5 m / min or more, and for example, 30 m / min or less, preferably 25 m / min or less.

[0117] The tension of the laminated film 2 is, for example, 30 N / m or more, preferably 35 N / m or more, more preferably 38 N / m or more, even more preferably 40 N / m or more, and also, for example, 100 N / m or less, preferably 80 N / m or less, more preferably 70 N / m or less, even more preferably 60 N / m or less.

[0118] The tension of the laminated film 2 is measured, for example, by a tension sensor.

[0119] 4. Effects The winding body 1 of the present invention has a durometer hardness A measured from the outermost radial surface, which is between 84.1 and 94.5. Therefore, even if the winding body 1 is a laminated film 2 comprising a resin film 21 having voids 211, winding misalignment can be suppressed and traces on the surface of the laminated film 2 can be reduced.

[0120] Furthermore, the method for manufacturing a wound body according to the present invention is a method for manufacturing the wound body 1 described above, and includes a step of winding a laminated film 2. Therefore, it is possible to manufacture a wound body 1 that suppresses winding misalignment and reduces marks on the surface of the laminated film 2.

[0121] 5. Variations In the modified examples, components and processes similar to those in the first embodiment are given the same reference numerals, and their detailed descriptions are omitted. Furthermore, the modified examples can achieve the same effects and advantages as the first embodiment, unless otherwise specified. Moreover, the first embodiment and its modified examples can be combined as appropriate.

[0122] In one embodiment of the above-described method for manufacturing the wound body, the wound body 1 is manufactured in a separate process from the manufacturing of the laminated film 2, but the method is not limited to this.

[0123] Specifically, the manufacturing of the laminated film 2 and the manufacturing of the wound body 1 may be carried out in succession. A modified example of a method for manufacturing a wound body includes, for example, a step of supplying a resin film 21 (supply step), a step of manufacturing the laminated film 2 (film formation step), a step of adjusting the tension applied to the laminated film 2 (tension adjustment step), and a step of winding the laminated film 2 (winding step).

[0124] In the modified method for manufacturing a wound body, the wound body 1 is manufactured, for example, using a sputtering deposition apparatus in a roll-to-roll manner. The sputtering deposition apparatus comprises, for example, a delivery roll, a deposition section, a tension adjustment section, and a winding roll (winding core 3).

[0125] Specifically, first, the resin film 21 is set on the feed roll of the sputtering deposition apparatus described above.

[0126] Next, one end of the resin film 21 in the longitudinal direction is attached to the winding roll (winding core 3) via an adhesive member.

[0127] Then, by driving the first and second drive sources and rotating the feed roll and the winding roll, the resin film 21 is fed out from the feed roll (feeding process), a metal reflective layer 22, an inorganic blackening layer 23, and a cured resin layer 24 are formed in the film formation section (film formation process), and the tension is adjusted by the tension adjustment section (tension adjustment process) while the laminated film 2 is wound up by the winding roll (winding process).

[0128] As a result, a laminated film 2 is manufactured from the resin film 21 using a roll-to-roll method, and the laminated film 2 is wound by a winding roll to produce a wound body 1. [Examples]

[0129] The present invention will be further described below with reference to examples, comparative examples, and reference examples. However, the present invention is not limited to the examples, comparative examples, and reference examples. Furthermore, specific numerical values ​​such as blending ratios (content ratios), physical properties, and parameters used in the following description may be replaced with the upper limits (numerical values ​​defined as "less than or equal to" or "less than") or lower limits (numerical values ​​defined as "greater than or equal to" or "greater than") of the corresponding blending ratios (content ratios), physical properties, and parameters described in the "Modes for Carrying Out the Invention" above.

[0130] Example 1 First, a long-length resin film of white polyethylene terephthalate (PET) film (product name: Lumirror E20, thickness 38 μm, manufactured by Toray Industries, Inc.) was prepared. The white PET film contains voids and titanium dioxide particles. The total light transmittance of the white PET film was 15.4%. The total light transmittance was calculated by measuring the spectrum at wavelengths of 380 nm to 780 nm using a spectrophotometer (U4100, manufactured by Hitachi High-Tech Science Corporation).

[0131] Next, a metallic reflective layer and an inorganic blackening layer were sequentially formed on one side in the thickness direction of the white PET film by sputtering. A roll-to-roll sputtering apparatus (DC magnetron sputtering apparatus) was used to form the metallic reflective layer and the inorganic blackening layer. The sputtering apparatus comprises a delivery chamber, a first deposition chamber, a second deposition chamber, and a winding chamber. The delivery chamber is equipped with a delivery roll. A roll of the resin film (white PET film) described above was set on the delivery roll as the work film. The winding chamber is equipped with a winding roll that can wind the work film. In the first and second deposition chambers, the deposition process can be carried out while the work film is driven from the delivery chamber to the winding chamber in a roll-to-roll manner.

[0132] In the sputtering deposition process, specifically, a first sputtering deposition was performed in the first deposition chamber, followed by a second sputtering deposition in the second deposition chamber. Afterward, the work film (substrate film / metallic reflective layer / inorganic blackening layer) was wound onto a winding roll in the winding chamber. In the first sputtering deposition, a 75 nm thick metallic reflective layer (Al) was formed on one side of the white PET film in the thickness direction. In the subsequent second sputtering deposition, a 50 nm thick inorganic blackening layer (In2O3+Cu) was formed on one side of the metallic reflective layer in the thickness direction. Each sputtering deposition was specifically as follows:

[0133] In the first sputtering deposition process, the sputtering deposition apparatus (delivery chamber, first deposition chamber, second deposition chamber, winding chamber) was evacuated, and argon (Ar) was introduced as the sputtering gas into the first deposition chamber, setting the atmospheric pressure inside the first deposition chamber to 0.3-0.4 Pa. An aluminum (Al) target (manufactured by Mitsui Mining & Smelting Co., Ltd.) was used as the target. A DC power supply was used to apply voltage to the target. The deposition temperature (temperature of the resin film on which the Al layer is laminated) was set to 40°C. The type of power supply and deposition temperature were the same for the second sputtering deposition process.

[0134] In the second sputtering deposition process, after evacuating the sputtering deposition apparatus described above, Ar was introduced as the sputtering gas into the second deposition chamber, and the atmospheric pressure inside the second deposition chamber was set to 0.3-0.4 Pa. A black inorganic target (product name: DIABLA12, a mixed target of indium oxide (In2O3) and copper (Cu), with an In content of 67.3 (±3) mass%, manufactured by Mitsubishi Materials Corporation) was used as the target.

[0135] Next, a curable resin composition was applied to one side of the inorganic blackening layer in the thickness direction by gravure coating to form a coating film. The curable resin composition contains ultraviolet-curable acrylic urethane resin (product name: Aicatron Z-878-16L, manufactured by Aica Kogyo Co., Ltd.), microparticles (product name: SSX103, cross-linked polymethacrylate particles, average particle size (D50) 3.0 μm, manufactured by Sekisui Chemical Co., Ltd.), and methyl ethyl ketone as a solvent. After drying the coating film, it was cured by ultraviolet irradiation to form a hard coat layer (HC layer) with a thickness of 1 μm.

[0136] The laminated film was fabricated as described above. The laminated film has a laminated structure consisting of a void-containing resin film (white PET film, 38 μm thick), a metal reflective layer (Al, 75 nm thick), an inorganic blackening layer (In2O3 + Cu, 50 nm thick), and an HC layer (1 μm thick).

[0137] Next, one end of the resulting laminated film in the longitudinal direction was attached to a core and wound up using a slitting machine. The slitting machine comprises a feed roll, a tension adjustment unit, and a winding roll.

[0138] Specifically, first, a laminated film processed to a width of 330 mm was set on the feed roll. Next, a cylindrical core (cushioned ABS core, manufactured by Hiroho Co., Ltd.) with a diameter of 77.2 mm and a width of 342 mm was prepared as a winding roll, and a 5 μm thick, 330 mm x 120 mm double-sided tape (No. 5600, manufactured by Nitto Denko Co., Ltd.) was attached to the surface of the core, 6 mm apart from both ends of the core. The 330 mm side of the double-sided tape was attached parallel to the width direction of the core, and the 120 mm side of the double-sided tape followed the circumference of the core. Then, the laminated film was fed from the feed roll, and at one end of the longitudinal direction of the laminated film, the HC layer side was facing inward, and the laminated film was attached to the double-sided tape so that it overlapped with one side of the 330 mm tape and both sides of the 120 mm tape.

[0139] Then, when the laminated film was transported at a conveying speed of 18 m / min, the tension was adjusted in the tension adjustment unit so that a tension of 40 N / m was applied to the laminated film, and the laminated film was wound onto the winding core. The laminated film was cut when a length of 200 m in the longitudinal direction had been wound. In this way, the wound body of Example 1 was obtained.

[0140] Example 2 The wound body of Example 2 was prepared in the same manner as in Example 1, except that the laminated film was adjusted to have a tension of 60 N / m.

[0141] Example 3 The winding body of Example 3 was manufactured in the same manner as in Example 1, except that the laminated film was transported at a transport speed of 13 m / min.

[0142] Comparative Example 1 A winding body of Comparative Example 1 was prepared in the same manner as in Example 1, except that the laminated film was adjusted to have a tension of 100 N / m.

[0143] Comparative Example 2 A winding body of Comparative Example 2 was prepared in the same manner as in Example 1, except that the laminated film was adjusted to have a tension of 30 N / m.

[0144] Reference example 1 A rolled body of Reference Example 1 was prepared in the same manner as in Example 1, except that a standard transparent polyethylene terephthalate (PET) film (product name: Lumirror U483, thickness 38 μm, manufactured by Toray Industries, Inc.) was used as the long resin film. The transparent PET film was void-free and particle-free. The total light transmittance of the transparent PET film was 92%. The total light transmittance was calculated by measuring the spectrum from wavelength 380 nm to 780 nm using a spectrophotometer (U4100, manufactured by Hitachi High-Tech Science Corporation).

[0145] <Rating> [Durometer hardness A] For each example, each comparative example, and the winding body of Reference Example 1, the durometer hardness A was measured from the outermost radial surface of the winding body using a Type A durometer in accordance with JIS K6253-1997. The durometer hardness A was measured at the center of the widthwise portion of the winding body, and the average value of five measurements taken circumferentially was calculated. The results are shown in Table 1.

[0146] [exterior] In each example, each comparative example, and the windings of Reference Example 1, the laminated film surface was observed to check for the presence or absence of marks. Specifically, the windings were stored at room temperature for one week, and after storage, the laminated film was unwound from the windings and the presence or absence of marks (tape marks from double-sided tape) on the surface of the HC layer was visually checked. The evaluation was based on the unwound length at which marks were observed, according to the following criteria. Note that a longer unwound length indicates a smaller area of ​​defect (tape marks). The results are shown in Table 1. {standard} A: The extension length is 190m or more. B: The extension length is 180m or more, but less than 190m. C: The extension length is less than 180m.

[0147] [winding misalignment] For each embodiment, each comparative example, and Reference Example 1, a force gauge (model: FGN-250HB) was pressed against the radial center of one widthwise side surface (the midpoint between the outer surface of the core and the outermost surface of the winding body) to measure the load at which winding misalignment occurred in the winding body. The results are shown in Table 1. Note that "250N≦" indicates that no winding misalignment occurred even when a load of 250N was applied.

[0148] Furthermore, the presence or absence of winding misalignment was visually inspected for each example, each comparative example, and the winding body of Reference Example 1. The results are shown in Table 1.

[0149] [Table 1]

[0150] <Consideration> In the windings of Examples 1 to 3, the durometer hardness A measured from the outermost radial surface was between 84.1 and 94.5. Therefore, winding misalignment was suppressed while surface marks on the laminated film were suppressed. Specifically, no winding misalignment was observed in Examples 1 to 3. In addition, in Examples 1 to 3, no defects (tape marks) were observed in the laminated film for more than 190m out of 200m. In other words, the area where defects occurred was less than 10m.

[0151] On the other hand, the winding material of Comparative Example 1 had a durometer hardness A of 94.8, measured from the outermost radial surface. Therefore, although winding misalignment was suppressed, surface marks on the laminated film could not be suppressed. Specifically, in Comparative Example 1, the area over which defects (tape marks) occurred in the laminated film was more than 10 m larger out of 200 m compared to Examples 1 to 3.

[0152] Furthermore, the durometer hardness A of the wound material in Comparative Example 2, measured from the outermost radial surface, was 84.0. Therefore, winding misalignment could not be suppressed.

[0153] Furthermore, even under the same conditions as Comparative Example 1, the winding of Reference Example 1 suppressed winding misalignment while also suppressing surface marks on the laminated film. The winding of Reference Example 1 uses a normal transparent PET film without voids, and it is presumed that this was possible because such a transparent PET film leaves fewer marks on the laminated film surface than the white PET film with voids used in Examples 1 to 3. [Explanation of symbols]

[0154] 1 Coiled body 2 Laminated film 3 cores 21 Resin film 22 Metal reflective layer 23 Inorganic blackening layer 24 Cured resin layer 211 Void 212 particles

Claims

1. A winding of a laminated film comprising a resin film, The resin film has voids, A wound body having a durometer hardness A measured from the outermost radial surface of the wound body, which is 84.1 or greater and 94.5 or less.

2. The wound body according to claim 1, wherein the total light transmittance of the resin film is less than 50%.

3. The winding body according to claim 1, wherein the resin film contains particles.

4. The winding body according to claim 1, wherein the laminated film further comprises a metallic reflective layer.

5. A method for manufacturing a wound body according to any one of claims 1 to 4, A method for manufacturing a wound body, comprising the step of winding the laminated film.

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