Laminate film and manufacturing method of laminate film

Abstract

To provide a laminate film capable of preventing a pattern shape of an ink from being excessively distorted.SOLUTION: A laminate film includes an adhesive layer, a resin layer and a release liner in this order. The resin layer includes a resin part disposed above and alienated from the adhesive layer. The resin part has an equivalent diameter of 150 μm or less.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] The present invention relates to a laminated film and a method for producing the laminated film. [Background technology]

[0002] It is known that disposing a low-refractive index layer having a porous structure on a substrate improves the light reflection efficiency and improves and maintains the intensity of light emitted from optical components such as lighting devices equipped with a light source and a light guide layer. Furthermore, optical components capable of distributing light by partially disposing a low-refractive index layer on a substrate to change the light extraction position have been produced. By using such an optical component, an optical component can be realized that can efficiently distribute light irradiated onto the light guide layer and extract desired light. For example, in order to partially arrange a low refractive index layer, a technology has been proposed in which a laminated film on which an ink pattern is formed is produced, and the ink pattern is transferred onto the coating film of a laminate in which a material for forming a low refractive index layer is coated on a substrate (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2019 / 182100 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when the laminated film is stored in a roll, the shape of the ink pattern may change significantly. An object of the present invention is to provide a laminated film that can suppress excessive deformation of the ink pattern, and a method for producing the same. [Means for solving the problem]

[0005] [1] A laminated film according to an embodiment of the present invention comprises, in this order, a pressure-sensitive adhesive layer, a resin layer, and a release liner. The resin layer includes resin portions spaced apart from one another on the pressure-sensitive adhesive layer. The equivalent diameter of the resin portions is 150 μm or less. [2] In the laminated film according to the above [1], the resin portion may contain at least one selected from the group consisting of a dried product, a semi-cured product, and a cured product of a resin composition. [3] In the laminated film described in [2] above, the resin composition may contain a photocurable resin. [4] In the laminated film described in [3] above, the photocurable resin may contain at least one resin selected from the group consisting of urethane (meth)acrylate, epoxy (meth)acrylate, and polyester (meth)acrylate. [5] In the laminate film according to any one of [1] to [4] above, the pressure-sensitive adhesive layer may have a nanoindentation hardness of 0.5 MPa or more when measured using a nanoindenter in accordance with ISO 14577 by pressing an indenter 2000 nm deep. [6] In the laminated film according to any one of the above [1] to [5], the ratio of the area of ​​the resin portion to the total area of ​​the pressure-sensitive adhesive layer may be 60% or less. [7] A method for manufacturing a laminated film according to another aspect of the present invention includes arranging resin portions constituting a resin layer on a pressure-sensitive adhesive layer on a laminate having a support member and a pressure-sensitive adhesive layer, the resin portions being spaced apart from each other, and arranging a release liner covering the laminate and the resin portions. [8] The method for producing a laminated film according to [7] above may include heating the resin portion after arranging the resin portion. [9] The method for producing a laminated film according to the above [7] or [8] may include winding the film into a roll after disposing the release liner. [Effects of the Invention]

[0006] According to an embodiment of the present invention, a laminated film capable of suppressing excessive deformation of the ink pattern can be obtained. [Brief explanation of the drawings]

[0007] [Figure 1A] 1 is a schematic cross-sectional view of a laminated film according to one embodiment of the present invention. [Figure 1B] 1B is a schematic plan view showing the laminated film of FIG. 1A as seen through a release liner. [Figure 2] FIG. 1 is a schematic perspective view showing an example in which a laminated film according to one embodiment of the present invention is formed into a roll. [Figure 3] FIG. 2 is a schematic cross-sectional view showing an example of peeling off a release liner from a laminate film according to one embodiment of the present invention. [Figure 4A] 1 is a schematic cross-sectional view of an optical element according to one embodiment of the present invention. [Figure 4B] FIG. 4 is a schematic cross-sectional view of an optical member according to another embodiment of the present invention. [Figure 5] 1 is a schematic cross-sectional view showing an example of a process for manufacturing an optical member according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0008] Representative embodiments of the present invention will be described below, but the present invention is not limited to these embodiments. Note that the drawings are drawn schematically or conceptually for ease of viewing and understanding, and the length, width, shape, size, ratio, direction, number, etc. may differ from the actual ones, and there may be no correspondence between the drawings. In this specification, "A and / or B" means any one of "A", "B", or "A and B". Also, in this specification, "(meth)acrylic" means "methacrylic" and / or "acrylic". For example, "(meth)acrylate" means "methacrylate" and / or "acrylate".

[0009] A. Overall structure of laminated film FIG. 1A is a schematic cross-sectional view of a laminated film according to one embodiment of the present invention. The laminated film 100 in the illustrated example comprises, in this order, a pressure-sensitive adhesive layer 10, a resin layer 20, and a release liner 30. The resin layer 20 includes resin portions 21 that are spaced apart from one another on the pressure-sensitive adhesive layer 10. The equivalent diameter of the resin portions 21 is 150 μm or less.

[0010] Typically, a laminate film can be stored in a roll form by winding a long laminate of multiple films together with a release liner on either or both sides of the outermost layer of the laminate. Furthermore, the laminate film can be unwound from the roll at any appropriate time and used for various purposes.

[0011] Furthermore, a predetermined pattern shape may be formed on the laminate film using ink. However, as described above, the laminate film is wound into a roll and stored in a rolled state, and the shape of the ink pattern on the laminate film may change significantly before and after storage. Specifically, the ink may spread excessively in the planar direction of the placement surface and / or may be deformed, such as by swelling or sinking in the thickness direction, making it impossible to maintain the desired pattern shape.

[0012] Therefore, the present inventors conducted extensive research to provide a laminate film that can suppress excessive deformation of the ink pattern even when stored in a rolled state, and as a result, they completed a laminate film according to an embodiment of the present invention. That is, a laminate film according to an embodiment of the present invention comprises, in this order, a pressure-sensitive adhesive layer, a resin layer, and a release liner. The resin layer includes resin portions spaced apart from one another on the pressure-sensitive adhesive layer. The resin portions have an equivalent diameter of 150 μm or less. By having such a configuration, a laminate film according to an embodiment of the present invention can suppress excessive deformation of the ink (essentially, the resin portions that may constitute the resin layer) even when wound around a roll and stored in roll form. Therefore, the laminate film according to an embodiment of the present invention can suppress excessive shape change of the ink pattern. The reason why excessive shape change of the ink pattern can be suppressed in a laminate film according to an embodiment of the present invention is not necessarily clear, but the following mechanism is presumed. In the laminate film according to an embodiment of the present invention, the ink (resin portion) has a relatively small diameter, which reduces the contact area between the resin portions spaced apart on the adhesive layer and the adhesive layer and the release liner. This reduces deformation caused by surface tension between the individual resin portions and the adhesive layer and the release liner. As a result, it is believed that ink deformation is less likely to occur, thereby preventing excessive changes in the shape of the ink pattern. Note that this mechanism is merely speculation and is not intended to restrict or limit the present invention.

[0013] As described above, the laminate film according to the embodiment of the present invention suppresses excessive shape change of the ink (resin portion) pattern, and therefore is suitable for use in imparting a desired pattern shape by transfer to a transfer substrate. For example, the laminate film according to the embodiment of the present invention can be suitable for use in producing an optical component having a pattern shape. Furthermore, when the laminate film is used in the production of an optical component, the desired pattern shape can be imparted to the optical component, and product defects of the optical component can be suppressed. Furthermore, because deformation of the resin portion in the laminate film is suppressed, interference between resin portions can be suppressed even during transfer, which can contribute to reducing product defects when producing an optical component.

[0014] In this specification, the term "ink" refers to a liquid or paste-like substance of a resin material and / or a resin composition containing a resin material.

[0015] The equivalent diameter of the resin portion in the laminate film according to an embodiment of the present invention is 150 μm or less. As described above, a diameter equivalent of 150 μm or less can contribute to suppressing excessive deformation of the ink (resin portion) pattern. Furthermore, since excessive deformation of the resin portion is less likely to occur, this can also contribute to forming fine patterns using the ink (resin portion). The "equivalent diameter of the resin portion" refers to the diameter of a circle when the resin portion is assumed to have a circular shape in plan view. The equivalent diameter of the resin portion can be calculated from images obtained by observing the resin portion with a laser microscope and processing the image after pressurizing a 90 μm-thick laminate film at a temperature of 25°C and a pressure of 0.40 MPa for 13 hours. A more specific measurement method is described in "(2) Ink height, ink diameter, and ink shape change rate after pressurization" in the Examples section below. Note that the above conditions are merely employed to confirm the equivalent diameter and are not intended to limit the measurement of the equivalent diameter under conditions other than those described above. For example, the diameter of the resin portion of the laminated film before pressure is applied may be measured.

[0016] The equivalent diameter of the resin portion in the laminate film according to an embodiment of the present invention is preferably 145 μm or less, more preferably 110 μm or less, even more preferably 80 μm or less, particularly preferably 70 μm or less, and particularly preferably 65 μm or less. Meanwhile, the lower limit of the equivalent diameter of the resin portion is not particularly limited, and is, for example, 5 μm or more. Within this range, the laminate film according to an embodiment of the present invention has excellent pressure resistance, which can contribute to suppressing deformation of the ink pattern. Because the diameter is relatively small within this range, it is believed that even when pressure is applied in the thickness direction of the laminate film, for example, when it is wound into a roll, the resin portion does not deform significantly and its shape is relatively easily maintained.

[0017] In a laminate film according to an embodiment of the present invention, when a 90 μm-thick laminate film is pressurized for 13 hours under conditions of a temperature of 25°C and a pressure of 0.40 MPa, the equivalent diameter of the resin portion is preferably 2.5 times or less, more preferably 2.35 times or less, even more preferably 2.15 times or less, and particularly preferably 2.0 times or less, of the equivalent diameter before pressurization. Within this range, the pressure resistance of the resin portion is particularly excellent. As a result, shape changes of the ink (resin portion) in the laminate film according to an embodiment of the present invention can be particularly suppressed. The equivalent diameter of the resin portion after pressurization may be, for example, 1.0 times or more of the equivalent diameter before pressurization. A specific method for measuring the equivalent diameter before pressurization is based on, for example, the method described in "(1) Ink height and ink diameter before pressurization" in the Examples below.

[0018] In the laminate film according to an embodiment of the present invention, the ratio of the area of ​​the resin portion to the total area of ​​the pressure-sensitive adhesive layer is preferably 60% or less, more preferably 55% or less, and even more preferably 50% or less. The ratio of the area of ​​the resin portion to the total area of ​​the pressure-sensitive adhesive layer is, for example, 1% or more. Within this range, even when the laminate film according to an embodiment of the present invention is rolled, excessive changes in the shape of the ink pattern can be particularly suppressed. The "area of ​​the resin portion" refers to the total area of ​​each separated resin portion. The area of ​​the pressure-sensitive adhesive layer and the area of ​​the resin portion are calculated from images obtained by observing the pressure-sensitive adhesive layer and the resin portion with a laser microscope and processing the images, as described above.

[0019] As described above, the resin layer 20 includes a plurality of resin portions 21. The resin portions are spaced apart from one another on the adhesive layer. In other words, the resin portions constitute the resin layer. The resin portions are spaced apart from one another on the adhesive layer, which can contribute to suppressing excessive changes in the shape of the ink pattern. This can therefore contribute to further improving the light extraction efficiency of optical components that can be fabricated from the laminate film according to the embodiment of the present invention. The resin portion is preferably disposed directly on the pressure-sensitive adhesive layer. "Directly disposed" means that the resin portion is disposed in contact with the pressure-sensitive adhesive layer.

[0020] The longitudinal and widthwise spacing between adjacent resin portions within the plane of the laminate film according to an embodiment of the present invention is each independently preferably 5 μm or more, more preferably 10 μm or more. Meanwhile, the longitudinal and widthwise spacing between adjacent resin portions is each independently preferably 300 μm or less, more preferably 250 μm or less, and even more preferably 100 μm or less. When the longitudinal and widthwise spacing between adjacent resin portions is within the above ranges, the shape of the pattern of the resin layer (ink) of the laminate film according to an embodiment of the present invention can be made finer. The longitudinal and widthwise spacings refer to the distance between the centers (area centers of gravity) of adjacent resin portions.

[0021] In one embodiment of the laminated film, the pattern of the resin portion (ink) is preferably such that the resin portions are arranged at approximately equal intervals in a plan view, and more preferably such that the resin portions are arranged at approximately equal intervals in a grid pattern in a plan view. In other words, more preferably, the resin portions are arranged at approximately equal intervals in the length direction and width direction on the pressure-sensitive adhesive layer. In this case, the respective lengthwise intervals and widthwise intervals are approximately equal to each other. "Approximately equal intervals" is not limited to strictly the same intervals, and an interval within a range of ±5 μm is acceptable as approximately equal intervals. The same applies to "approximately equal."

[0022] A laminate film according to one embodiment of the present invention may essentially include a support member on the side opposite the release liner of the pressure-sensitive adhesive layer. In the illustrated example (see FIG. 1A), the laminate film 100 includes a support member 40, a pressure-sensitive adhesive layer 10, a resin layer 20, and a release liner 30, in that order. The support member 40 supports, for example, the pressure-sensitive adhesive layer 10. However, the support member 40 is not an essential component of the laminate film according to the embodiment of the present invention. The laminate film according to the embodiment of the present invention can be stored typically by winding a long laminate film 100 into a roll as shown in the illustrated example (e.g., FIG. 2). In FIG. 2, the laminate film is wound so that the release liner 30 faces inward. However, the present invention is not limited to this, and the laminate film may be wound so that the opposite side of the release liner 30 (the support member 40 side in FIG. 2) faces inward, for example.

[0023] B. Details of the laminated film Next, the components of the laminated film according to the embodiment of the present invention will be specifically described.

[0024] B-1.Adhesive layer For example, when producing an optical component including a low refractive index layer having voids, the pressure-sensitive adhesive layer can be used adjacent to the main surface of the low refractive index layer. Specifically, the pressure-sensitive adhesive layer is bonded to the low refractive index layer. When bonded to the low refractive index layer, the pressure-sensitive adhesive layer preferably has a hardness such that the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer does not penetrate into the voids of the low refractive index layer under normal conditions. The storage modulus of the pressure-sensitive adhesive layer at 23°C is, for example, 1.0 × 10 5 (Pa) ~ 1.0 × 10 7 (Pa), preferably 1.3 × 10 5 (Pa) ~ 1.0 × 10 6 (Pa), and more preferably 1.5 × 10 5 (Pa) ~ 5.0 × 10 5 (Pa). By setting the storage modulus of the pressure-sensitive adhesive layer that can be adjacent to the low refractive index layer within the above range, the pressure-sensitive adhesive that constitutes the pressure-sensitive adhesive layer can be prevented from penetrating into the voids in the low refractive index layer, thereby maintaining the refractive index of the low refractive index layer at a low level and maintaining its effectiveness. The storage modulus is determined by reading the value at 23°C when measured at a frequency of 1 Hz, in the range of -50°C to 150°C, and at a heating rate of 5°C / min, in accordance with the method described in JIS K7244-1 "Plastics - Test methods for dynamic mechanical properties."

[0025] The nanoindentation hardness of the pressure-sensitive adhesive layer is preferably 0.50 MPa or more, more preferably 0.60 MPa or more, and even more preferably 0.65 MPa or more. Meanwhile, the nanoindentation hardness of the pressure-sensitive adhesive layer may be, for example, 2.00 MPa or less. The nanoindentation hardness of the pressure-sensitive adhesive layer is measured in accordance with ISO 14577. Specifically, the nanoindentation hardness is obtained by placing a member (e.g., a member having a pressure-sensitive adhesive layer) in a nanoindenter and pressing the indenter 2000 nm into the member. As the nanoindenter, for example, an apparatus manufactured by Oxford Instruments (model "MFP-3D-SA") or the like is used, and the nanoindentation hardness can be measured, for example, by the AFM force curve method.

[0026] Any suitable adhesive can be used as the adhesive constituting the adhesive layer as long as it has the above-mentioned properties. A typical example of the adhesive is an acrylic adhesive (acrylic adhesive composition). An acrylic adhesive composition typically contains a (meth)acrylic polymer as a main component (base polymer).

[0027] The weight average molecular weight Mw of the (meth)acrylic polymer is, for example, 100,000 to 5,000,000, and preferably 200,000 to 4,000,000. The weight average molecular weight Mw can be calculated, for example, from the results of GPC measurement in terms of styrene.

[0028] The (meth)acrylic polymer may be contained in the pressure-sensitive adhesive composition in an amount of, for example, 50% by weight or more, preferably 70% by weight or more, and more preferably 90% by weight or more of the solid content of the pressure-sensitive adhesive composition. The (meth)acrylic polymer contains alkyl (meth)acrylate as a monomer unit as a main component.

[0029] Examples of the alkyl group of the alkyl (meth)acrylate include linear or branched alkyl groups having 1 to 18 carbon atoms. The average number of carbon atoms in the alkyl group is preferably 3 to 9. Examples of monomers constituting the (meth)acrylic polymer include, in addition to alkyl (meth)acrylates, comonomers such as carboxyl group-containing monomers, hydroxyl group-containing monomers, amide group-containing monomers, aromatic ring-containing (meth)acrylates, and heterocycle-containing (meth)acrylates. The comonomer is preferably a hydroxyl group-containing monomer and / or a heterocycle-containing (meth)acrylate, and more preferably N-acryloylmorpholine.

[0030] The acrylic pressure-sensitive adhesive composition may preferably contain a silane coupling agent and / or a crosslinking agent. Examples of the silane coupling agent include an epoxy group-containing silane coupling agent. Examples of the crosslinking agent include an isocyanate-based crosslinking agent and a peroxide-based crosslinking agent.

[0031] Details of such a pressure-sensitive adhesive layer or acrylic pressure-sensitive adhesive composition are described, for example, in Japanese Patent No. 4140736, the disclosure of which is incorporated herein by reference.

[0032] The thickness of the pressure-sensitive adhesive layer is preferably 3 μm or more, more preferably 5 μm or more. On the other hand, the thickness of the pressure-sensitive adhesive layer is preferably 30 μm or less, more preferably 15 μm or less. When the thickness of the pressure-sensitive adhesive layer is within this range, there is an advantage that the pressure-sensitive adhesive layer has sufficient adhesive strength while having a small effect on the overall thickness.

[0033] B-2.Release liner Typically, the release liner 30 is temporarily attached to the adhesive layer of the laminated film according to the embodiment of the present invention until the adhesive layer is attached to an object to be adhered, and is peeled off from the adhesive layer 10 when the laminated film is put to use (see FIG. 3). In the illustrated example (for example, FIG. 1B), the laminated film 100 is temporarily attached to the adhesive layer 10 (a position where the resin portion 20 is not arranged) and the resin portion 20.

[0034] The release liner 30 is formed of any suitable resin film that can be used as a release liner. Specific examples of materials that are the main components of the resin film include polyethylene terephthalate (PET), polyethylene, and polypropylene. The resin film materials can be used alone or in combination. The release liner 30 may be transparent or not.

[0035] The release liner 30 may be a resin film with one or both main surfaces subjected to a release treatment. Specifically, a release treatment layer may be provided on one or both main surfaces of the release liner 30. Examples of release treatment agents that form the release treatment layer include silicone-based release treatment agents, fluorine-based release treatment agents, and long-chain alkyl acrylate-based release agents, with silicone-based release treatment agents being preferred, and vinyl group-containing addition silicone being more preferred. The release treatment agents can be used alone or in combination. The thickness of the release treatment layer is typically 50 nm or more and 400 nm or less.

[0036] The thickness of the release liner 30 is typically 5 μm or more, preferably 20 μm or more, and typically 60 μm or less, preferably 45 μm or less. If a release treatment layer is applied, the thickness of the release liner includes the thickness of the release treatment layer.

[0037] B-3.Resin layer The resin layer in the laminate film according to an embodiment of the present invention includes resin portions spaced apart from one another and arranged on the pressure-sensitive adhesive layer. The resin portions may be formed from a resin composition (ink). More specifically, the resin portions include a liquid or paste-like ink formed by applying the resin composition onto the pressure-sensitive adhesive layer. The resin portions preferably include a dried product, a semi-cured product, and a cured product of the resin composition.

[0038] The resin composition typically contains a resin material and, if necessary, additives and / or a solvent. Any appropriate resin material can be used as the resin material depending on the purpose. The resin material includes, for example, an active energy ray-curable resin. Examples of the active energy ray-curable resin include photocurable resins. That is, the resin composition preferably contains a photocurable resin. When the resin composition contains a photocurable resin, the timing for curing the resin composition can be easily controlled. For example, when the laminate film of the present invention is applied to a low refractive index layer having a porous layer, and an ink pattern shape of the laminate film is imparted to the low refractive index layer, the ink made from the resin composition can be transferred and then cured by irradiating with light. As a result, optical components imparted with a high-definition ink pattern shape can be efficiently produced.

[0039] The photocurable resin is typically an ultraviolet-curable resin. Specific examples of the ultraviolet-curable resin include (meth)acrylic, urethane, amide, silicone, epoxy, and polyester resins. These resins may contain photocurable monomers, oligomers, and polymers. These resins may be used alone or in combination.

[0040] The (meth)acrylic resin contains a monomer component and / or an oligomer component having preferably two or more, more preferably three to six, polymerizable functional groups. Specific examples of the acrylic resin include epoxy (meth)acrylate, polyester (meth)acrylate, (meth)acrylic (meth)acrylate, and ether (meth)acrylate. The photocurable resin preferably contains at least one resin selected from the group consisting of urethane (meth)acrylate, epoxy (meth)acrylate, and polyester (meth)acrylate. By including such a resin as the photocurable resin, it is easier to control the timing of curing the resin composition, allowing for more efficient production of optical members having a high-definition ink pattern. In particular, it is particularly preferable for the photocurable resin to contain urethane (meth)acrylate.

[0041] The resin composition may contain any appropriate additive depending on the type, blend, and composition of the resin material. For example, when the resin composition contains a photocurable resin, the resin composition preferably contains a photopolymerization initiator. When curing the photocurable resin, any appropriate curing method may be adopted depending on the components, composition, structure, etc. of the resin. Curing methods include, for example, radical polymerization and cationic polymerization.

[0042] The thickness of the resin layer is preferably smaller than the thickness of the release liner. With such a configuration, the outermost layer of the laminated film according to the embodiment of the present invention can be made flat. As a result, the pressure applied to the inside of the laminated film when it is rolled can be further reduced. Note that the "thickness of the resin layer" here refers to the thickness of the resin layer (ink) before pressure is applied. The thickness of the resin layer is also calculated as the arithmetic average of the thicknesses of the resin portion before pressure is applied at three randomly selected points. The thickness of the resin layer before pressure application is preferably 1.5 μm or more and 5.6 μm or less, and the equivalent diameter of the resin portion before pressure application is 15 μm or more and 42 μm or less. The thickness of the resin layer before pressure application is more preferably 1.5 μm or more and 3.3 μm or less. Within these ranges, the laminate film according to the embodiment of the present invention has particularly excellent pressure resistance. As a result, deformation of the coating film of the laminate film according to the embodiment of the present invention can be particularly suppressed. As already mentioned, the specific method for measuring the thickness of the resin layer before pressure application is based on the method described in "(1) Ink height and ink diameter before pressure application" in the Examples below. The same applies to the equivalent diameter of the resin portion before pressure application.

[0043] B-4. Other configurations A laminate film according to one embodiment of the present invention includes a support member on the side of the pressure-sensitive adhesive layer opposite the resin layer. As described above, the support member supports, for example, the pressure-sensitive adhesive layer. For example, as shown in the illustrated example (e.g., FIG. 1A), a laminate film 100 includes a support member 40, a pressure-sensitive adhesive layer 10, a resin layer 20, and a release liner 30, in this order. The support member 40 supports, for example, the pressure-sensitive adhesive layer 10 in the laminate film 100 according to one embodiment of the present invention. When the laminate film according to the embodiment of the present invention is wound into a roll, the presence of the support member prevents the release liner (the outermost layer of the laminate film) from overlapping with the pressure-sensitive adhesive layer. As a result, the laminate film can be easily unwound from the roll. Furthermore, the pressure-sensitive adhesive layer can be protected until the optical component is used, allowing the adhesiveness to be maintained for a relatively long period of time.

[0044] For example, any appropriate resin film may be used for the support member 40. The resin film may contain the same main component material as the resin film constituting the release liner described in section B-2 above.

[0045] The support member 40 may be a release liner. That is, the support member may be a resin film having a surface subjected to a release treatment. The support member may be the same as or different from the release liner described above (the release liner in Section B-2 will be referred to as the first release liner for convenience). When the support member 40 is a release liner (referred to as the second release liner for convenience), an optical element can be produced from the laminate film according to an embodiment of the present invention, and the optical element can be easily used when applied to other elements (e.g., a light guide plate, etc.).

[0046] The support member may have any appropriate thickness. For example, the thickness of the support member is 5 μm or more and 100 μm or less. The thickness of the support member is preferably 10 μm or more.

[0047] B-5.Laminated film manufacturing method The laminate film according to the embodiment of the present invention can be produced, for example, by disposing a resin portion on a pressure-sensitive adhesive layer disposed on a support member to form a resin layer, and disposing a release liner that covers the resin layer and the pressure-sensitive adhesive layer. More specifically, the laminate film according to the embodiment of the present invention can be produced, for example, as follows.

[0048] First, a support member, a pressure-sensitive adhesive layer, a release liner, and a resin composition are prepared. The adhesive layer may be formed by applying any suitable adhesive (adhesive composition) constituting the adhesive layer onto a support member, or by transferring an adhesive layer formed on another support member. The laminate of the support member and the adhesive layer may be referred to as a first laminate (first laminate 110 in the illustrated example).

[0049] A resin composition is applied onto the pressure-sensitive adhesive layer of the first laminate. By applying the resin composition, the resin portions are spaced apart from one another. The resin portions can be produced by forming a coating film of the resin composition using any appropriate coating method. Examples of coating methods include coating methods such as spraying (spray coating), roll coating, and spin coating; and printing methods such as inkjet printing and screen printing. Any appropriate coating device can be used for coating. Specific examples of coating devices include spray coaters, roll coaters, spin coaters, dispensers, inkjet coaters (inkjet printers), and screen printers.

[0050] As an example, coating by inkjet printing will be described below. A resin composition (ink) is injected into the injection port of an inkjet device, and the first laminate is placed below the discharge port of the inkjet device with the adhesive layer facing the discharge port. Next, the resin composition is ejected from the ejection port of the inkjet device. Inkjet printing allows the resin composition to be easily ejected with the desired spacing. Therefore, by using the inkjet device, the resin portions can be easily spaced apart. As a result, the resin layer can be produced with a suitable ink pattern shape. In this way, a resin layer is formed on the adhesive layer. The resin portion may be disposed on the adhesive layer by, for example, discharging the resin portion onto the adhesive layer while conveying the first laminate with a roll. This allows a pattern of the resin portion (ink) to be formed on the resin layer.

[0051] The shape of each resin portion in the resin layer in plan view can be any appropriate shape. That is, the shape of the resin portion in plan view can be adjusted to any appropriate shape depending on the settings of the inkjet device, the type, composition, and composition ratio of the resin material, additives, and solvent of the resin composition, and the physical properties such as the viscosity of the resin composition. Examples of the shape of the resin portion in plan view include a circle, an ellipse, a rectangle, and a polygon. As long as the resin portions are spaced apart from each other in plan view, the shape of the resin portions in plan view may be formed in a band shape (also referred to as a line shape) in plan view.

[0052] Next, a release liner (or a first release liner when the support member is a second release liner) is placed on the PSA layer with the resin portion disposed thereon. The release liner can be placed over the resin portion and the side of the PSA layer on which the resin portion is not disposed. This allows the release liner to cover the resin portion and the PSA layer. This allows the production of a laminated film according to an embodiment of the present invention.

[0053] In one embodiment, the resin portion (resin composition) may be disposed on the pressure-sensitive adhesive layer, and then the resin composition may be dried under any appropriate conditions. When drying the resin composition, the resin portion disposed on the pressure-sensitive adhesive layer is preferably heated. As a result, the resin layer may be composed of a dried product, a semi-cured product, or a cured product of the resin composition. That is, the resin layer includes at least one of a dried product, a semi-cured product, and a cured product of the resin composition. The heating temperature is, for example, 80°C or higher and 150°C or lower, and the drying time is, for example, 1 minute or higher and 1 hour or lower. However, the drying conditions are not limited to those described above. For example, the resin portion may be dried by leaving it to stand at room temperature for any length of time without heating. Furthermore, the resin portion may be dried before or after disposing the release liner. In this manner, a laminated film according to an embodiment of the present invention may be produced.

[0054] In one embodiment, the method may include placing the release liner on the resin portion and the pressure-sensitive adhesive layer, and then winding the film into a roll. Therefore, the laminate film according to an embodiment of the present invention may be in a roll form. When a laminate film is wound into a roll, the pressure applied generally increases toward the inside of the roll, making the formed ink (resin portion) prone to deformation. In contrast, the laminate film according to an embodiment of the present invention has the advantage that excessive deformation of the resin portion is suppressed even when wound into a roll, and excessive change in the shape of the ink pattern can be suppressed. In this manner, a laminated film according to an embodiment of the present invention may be produced.

[0055] However, the method for producing a laminated film according to an embodiment of the present invention is not limited to the above-mentioned method and order, and may include any appropriate steps as long as the effects of the present invention are not impaired.

[0056] C. Optical Components C-1. Overall structure of optical components The laminated film according to the embodiment of the present invention can be, for example, a component of an optical element. Therefore, the embodiment of the present invention also includes such an optical element. Such an optical element will be described below.

[0057] FIG. 4A is a schematic cross-sectional view of an optical element according to one embodiment of the present invention. The optical element 200 in the illustrated example comprises, in this order, a substrate 50, a low refractive index layer 60, a pressure-sensitive adhesive layer 10, and a release liner 40. Resin portions 21 are arranged in the low refractive index layer 60 and spaced apart from one another. The equivalent diameter of the resin portions 21 is 150 μm or less. With this configuration, the optical element according to the embodiment of the present invention can suppress excessive changes in the ink pattern shape and can have a good pattern shape.

[0058] Optical elements according to embodiments of the present invention may typically have a light distribution function. The light distribution function refers to, for example, a function in which a laminated film is disposed on a light guide layer, causing a portion of light from a light source to be totally reflected by a low refractive index layer and partially blocking the light from exiting one side of the light guide layer, thereby allowing a portion of the light to exit the light guide layer from a location where the low refractive index layer is not provided, thereby adjusting the light intensity and thereby varying the degree of light extraction depending on the position of the light guide layer from the light source. Achieving light distribution can contribute to uniforming the brightness of light emitted from the light guide layer. As described above, the optical elements according to embodiments of the present invention suppress excessive shape changes in the ink (the resin portion of the resin layer), making it easy to apply a pattern of ink to the low refractive index layer and enabling finer patterns. Furthermore, according to the optical member of the present invention, defects in the pattern shape can be suppressed, and the optical member of the present invention can also be effectively miniaturized in the low refractive index layer, thereby realizing highly efficient light distribution.

[0059] Hereinafter, the components of the optical member according to the embodiment of the present invention will be described in detail. As described above, the optical member according to the embodiment of the present invention can use the laminate film according to the embodiment described in the above sections A and B (B-1 to B-5). Therefore, for the optical member according to the embodiment of the present invention, the description of the laminate film will be used for the configurations common to the laminate film, and the description will be omitted as appropriate.

[0060] C-2. Base material In the optical component, the substrate supports, for example, the low refractive index layer. The substrate may have a similar structure to the support member of the laminate film. Therefore, the description of the support member in Section B-4 of the laminate film can be applied to the substrate. Any appropriate resin film other than the support member described in section B-4 above may be used as the substrate. For example, the resin film may typically be a film or plate of resin (preferably a transparent resin). Typical examples of such resins include thermoplastic resins and reactive resins (e.g., ionizing radiation curable resins). Specific examples of thermoplastic resins include (meth)acrylic resins such as polymethyl methacrylate (PMMA) and polyacrylonitrile, polyester resins such as polycarbonate (PC) resin and PET, cellulose resins such as triacetyl cellulose (TAC), cyclic polyolefin resins, and styrene resins. Specific examples of ionizing radiation curable resins include epoxy acrylate resins and urethane acrylate resins. These resins may be used alone or in combination of two or more.

[0061] The refractive index of the substrate is preferably 1.47 or more, more preferably 1.47 to 1.60, and even more preferably 1.47 to 1.55. When the optical element according to the embodiment of the present invention is applied to a light guide layer (light guide member), the brightness of the light emitted from the light guide layer can be more uniform.

[0062] The substrate may have any appropriate thickness, for example, from 1 μm to 100 μm.

[0063] C-3. Low refractive index layer For example, when the optical member is applied to a light guide layer such as a light guide plate, the low refractive index layer has a function of efficiently reflecting light from a light source within the light guide layer. The refractive index of the low refractive index layer is lower than that of the substrate, for example. The refractive index of the low refractive index layer is, for example, 1.30 or less, with the lower limit exceeding 1.00. The refractive index of the low refractive index layer is preferably 1.13 to 1.28, more preferably 1.14 to 1.27, even more preferably 1.15 to 1.26, and particularly preferably 1.16 to 1.25. When the refractive index of the low refractive index layer is within this range, an optical element can be obtained in which a low refractive index layer having a pattern shape is disposed on a substrate, and the light distribution function can be particularly well exhibited. Unless otherwise specified, the refractive index refers to a refractive index measured at a wavelength of 550 nm. The refractive index can be measured, for example, by placing a sample of the low refractive index layer in an ellipsometer (JA Woollam Japan: VASE) at a wavelength of 550 nm and an incident angle of 50 to 80 degrees.

[0064] The total light transmittance of the low refractive index layer is preferably 85% to 99%, more preferably 87% to 98%, and even more preferably 89% to 97%. By providing such a low refractive index layer on the first main surface side of the substrate, for example, it is possible to achieve excellent transparency for the entire laminate film. As a result, for example, when the laminate film is applied to various products, visibility can be ensured. The total light transmittance can be measured, for example, using a haze meter (for example, "HM-150" manufactured by Murakami Color Research Laboratory Co., Ltd.).

[0065] The haze of the low refractive index layer is preferably less than 5%, more preferably less than 3%. On the other hand, the haze may be, for example, 0.1% or more, or 0.2% or more. By providing such a low refractive index layer on the first main surface side of the substrate, for example, it is possible to achieve excellent transparency for the entire laminate film. The haze can be calculated, for example, from the value measured with the same haze meter as above using the following formula: Haze (%) = [Diffuse transmittance (%) / Total light transmittance (%)] x 100 (%)

[0066] The thickness of the low refractive index layer is, for example, 0.1 μm or more, preferably 0.3 μm or more, more preferably 1.0 μm or more, even more preferably 1.2 μm or more, particularly preferably 1.5 μm or more, and particularly preferably 1.8 μm or more. The thickness of the low refractive index layer may be, for example, 2.2 μm or more, or, for example, 2.5 μm or more, or, for example, 2.8 μm or more. On the other hand, the thickness of the low refractive index layer may be, for example, 20 μm or less, or, for example, 10 μm or less, or, for example, 8 μm or less, or, for example, 5 μm or less. When the thickness of the low refractive index layer is within this range, the optical element according to the embodiment of the present invention can particularly effectively exhibit the light distribution function and the light intensity adjustment function.

[0067] The low refractive index layer has a porous structure. Any appropriate configuration can be adopted for the low refractive index layer as long as it can achieve the desired properties. As a material for forming the low refractive index layer (hereinafter, sometimes referred to as a "material for forming the low refractive index layer"), for example, materials described in International Publication No. 2004 / 113966, Japanese Patent Application Laid-Open No. 2013-254183, and Japanese Patent Application Laid-Open No. 2012-189802 can be adopted.

[0068] Representative examples of materials for forming low refractive index layers include silicon compounds. Examples of silicon compounds include silica-based compounds; hydrolyzable silanes and their partial hydrolysates and dehydration condensates; silicon compounds containing silanol groups; and activated silica obtained by contacting silicate with acid or ion exchange resin. Examples of materials for forming low refractive index layers include organic polymers; polymerizable monomers (e.g., (meth)acrylic monomers and styrene-based monomers); and curable resins (e.g., (meth)acrylic resins, fluorine-containing resins, and urethane resins). These materials may be used alone or in combination of two or more.

[0069] In one embodiment, the low refractive index layer may contain spaces such as pores and gaps therein. In this case, the porosity of the low refractive index layer is preferably 20 to 60 volume %, more preferably 25 to 55 volume %, even more preferably 30 to 50 volume %, and particularly preferably 35 to 45 volume %. Such a porosity allows the refractive index of the low refractive index layer to be within an appropriate range and ensures strength. Here, the porosity is a value calculated from the refractive index measured with an ellipsometer using the Lorentz-Lorenz formula.

[0070] The size of the pores that can be contained in the low refractive index layer can be adjusted to a desired size depending on the purpose and application. The size of the pores that can be contained in the low refractive index layer is, for example, 2 nm or more, preferably 5 nm or more, more preferably 10 nm or more, and even more preferably 20 nm or more. On the other hand, the size of the pores that can be contained in the low refractive index layer is, for example, 500 nm or less, preferably 200 nm or less, and more preferably 100 nm or less. Note that the size of the pores refers to the diameter of the major axis of the pores, out of the diameter of the major axis and the diameter of the minor axis.

[0071] The pore size can be quantified by the BET test method. In one embodiment, 0.1 g of a measurement sample (e.g., a fabricated low refractive index layer) is placed in the capillary of a specific surface area measurement device (e.g., Micromeritics' "ASAP2020"), and then dried under reduced pressure at room temperature for 24 hours to remove gases contained in the measurement sample. Then, nitrogen gas is adsorbed onto the measurement sample, and an adsorption isotherm is drawn to determine the pore distribution. This allows the pore size to be evaluated.

[0072] Examples of the low refractive index layer having an internal space include a porous layer made of a porous body and / or a layer containing an air layer in at least a portion thereof. That is, the low refractive index layer having an internal space includes at least one of the porous layer and the air layer.

[0073] The low refractive index layer typically contains aerogel and / or particles (for example, hollow fine particles and / or porous particles). The low refractive index layer is preferably a nanoporous layer (specifically, 90% or more of the pores have a diameter of 1×10 -1 nm~1×10 3 The porous layer may be in the range of 100 nm.

[0074] Any appropriate particles may be used as the particles. The particles are typically made of a silica-based compound. Examples of particle shapes include spherical, plate-like, needle-like, string-like, and bunch-of-grapes shapes. Examples of string-like particles include particles in which a plurality of spherical, plate-like, or needle-like particles are strung together like beads, short fiber-like particles (e.g., short fiber-like particles described in JP 2001-188104 A), and combinations thereof. The string-like particles may be linear or branched. Examples of bunch-of-grapes-like particles include particles in which a plurality of spherical, plate-like, and needle-like particles are aggregated to form a bunch of grapes. The particle shape can be confirmed, for example, by observation using a transmission electron microscope.

[0075] An example of a low refractive index layer is a structure composed of one or more types of structural units that form a fine void structure, and these structural units are bonded together (for example, chemically bonded via catalytic action). Examples of the shape of the structural units include particulate, fibrous, rod-like, and flat plate-like. The structural units may have only one shape, or may have two or more shapes in combination.

[0076] A specific example of a low refractive index layer is a porous layer composed of a porous body in which particles having micropores (hereinafter referred to as microporous particles) are chemically bonded to each other. Such a porous layer can be obtained, for example, by chemically bonding the microporous particles to each other. The shape of the microporous particles is not particularly limited and may be, for example, spherical or other shapes. Furthermore, the microporous particles may be, for example, sol-gel beaded particles, nanoparticles (e.g., hollow nanosilica nanoballoon particles), nanofibers, etc. Representative microporous particles include inorganic substances. Specific examples of inorganic substances include silicon (Si), magnesium (Mg), aluminum (Al), titanium (Ti), zinc (Zn), and zirconium (Zr). These may be used alone or in combination of two or more. In one embodiment, the microporous particles are, for example, microporous particles of a silicon compound, and the porous body is, for example, a silicone porous body. The microporous particles of a silicon compound include, for example, a pulverized gel silica compound.

[0077] Another example of a low refractive index layer is a layer containing a fibrous material such as nanofibers, in which spaces are formed by the entanglement of the fibrous material. Further examples of a low refractive index layer include a layer formed using hollow nanoparticles or nanoclay, or a layer formed using hollow nanoballoons or magnesium fluoride. The low refractive index layer may be composed of a single constituent material or multiple constituent materials. The low refractive index layer may be composed of a single form of the above examples, or multiple forms of the above examples.

[0078] The porous layer may have, for example, an open-cell structure, in which the pores are interconnected. An open-cell structure refers to a porous body (e.g., a porous silicone body) in which the pores are interconnected three-dimensionally, and can also be described as a state in which the pore spaces are interconnected. The open-cell structure of the porous layer can enhance porosity. It is difficult to form an open-cell structure using closed-cell particles with individual pore structures, such as hollow particles (e.g., hollow silica). However, when using silica sol particles (a pulverized product of a gel-like silicon compound that forms a sol), the silica sol particles can have a three-dimensional dendritic structure. The dendritic particles can settle and deposit in a coating film (a coating film of a sol containing a pulverized product of a gel-like silicon compound) to easily form an open-cell structure. The porous layer preferably has a monolithic structure in which the open-cell structure includes a distribution of multiple pores. The monolithic structure refers to, for example, a hierarchical structure including a structure with nano-sized pores and an open-cell structure in which nano-sized pores are aggregated. The monolithic structure, for example, can provide membrane strength through fine pores while providing high porosity through a coarse open-cell structure, thereby achieving both membrane strength and high porosity.

[0079] For example, the monolith structure can be formed by controlling the pore distribution of the resulting void structure in a gel (gel silicon compound) prior to pulverization into silica sol particles. Furthermore, for example, when pulverizing a gel silicon compound, the monolith structure can be formed by controlling the particle size distribution of the pulverized silica sol particles to a predetermined size. The particle size distribution can be measured, for example, using a particle size distribution evaluation device such as a dynamic light scattering method or a laser diffraction method, or an electron microscope such as a scanning electron microscope (SEM) or a transmission electron microscope (TEM).

[0080] As described above, the porous layer may contain pulverized gel compounds such as gel silicon compounds, and the pulverized particles are chemically bonded to each other. The chemical bonds are not particularly limited, and examples thereof include cross-linking, covalent bonding, and hydrogen bonding. The volume average particle size of the pulverized particles in the porous layer is, for example, 0.10 μm or more, preferably 0.20 μm or more, and more preferably 0.40 μm or more. Meanwhile, the volume average particle size of the pulverized particles in the porous layer is, for example, 2.00 μm or less, preferably 1.50 μm or less, and more preferably 1.00 μm or less. The volume average particle size is an index of the particle size variation of the pulverized particles and is determined by particle size distribution measurement.

[0081] The low refractive index layer may contain silicon atoms. For example, the silicon atoms contained in the low refractive index layer are preferably siloxane-bonded. Of all silicon atoms contained in the low refractive index layer, the proportion of unbonded silicon atoms (specifically, residual silanols) is, for example, less than 50%, preferably 30% or less, and more preferably 15% or less.

[0082] In one embodiment, the material for forming the low refractive index layer may be a coating liquid in which the above-mentioned material is dispersed in a dispersion medium. The dispersion medium can adjust the viscosity and other properties of the coating liquid to a suitable range. As a result, the coating properties when forming the low refractive index layer can be improved. The dispersion medium may be a single solvent or a mixed solvent containing multiple solvents.

[0083] Examples of dispersion media include alcohols such as ethanol, isopropyl alcohol, butanol, t-butanol, isobutyl alcohol, and 2-methoxyethanol (methyl cellosolve); esters such as ethyl acetate and butyl acetate; ethers such as diisopropyl ether and propylene glycol monomethyl ether; ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; and aromatic hydrocarbons such as toluene. These dispersion media can be used alone or in combination. Among these dispersion media, alcohols are more preferred, and isobutyl alcohol is even more preferred. The mass ratio of the dispersion medium to the total amount of the low refractive index layer-forming material is, for example, 5 mass% or more, preferably 30 mass% or more, more preferably 40 mass% or more, and is, for example, 100 mass% or less, preferably 95 mass% or less, more preferably 60 mass% or less. If the content ratio of the dispersion medium is within the above range, the viscosity of the low refractive index layer-forming material can be stably adjusted to a range suitable for spray coating.

[0084] In one embodiment, the coating film (a coating film of a sol containing a pulverized product of a gel-like silicon compound) can be formed using a coating liquid containing microporous particles, and the microporous particles can be chemically bonded to each other by heating (including drying) this coating liquid. The coating liquid containing microporous particles is, for example, a suspension. For example, a catalyst (crosslinking reaction accelerator) that accelerates crosslinking between the microporous particles (for example, a dehydration condensation reaction of residual silanol groups that may be contained in the microporous particles) and / or a substance (catalyst generator) that generates a catalyst (crosslinking reaction accelerator) may be added to the coating liquid. Examples of catalysts include photoactivated catalysts and thermally activated catalysts. Examples of catalyst-generating substances (catalyst generators) include photocatalyst generators and thermal catalyst generators. Examples of photocatalyst generators include photobase generators (catalysts that generate a basic catalyst upon light irradiation) and photoacid generators (substances that generate an acidic catalyst upon light irradiation). For example, the microporous particles may be a pulverized product of a gel-like compound (preferably a gel-like silicon compound), and the low refractive index layer may have a porous structure composed of a porous body (preferably a silicone porous body) containing the pulverized product of the gel-like compound. Such microporous particles may have a state in which the three-dimensional structure of the gel-like compound before pulverization is dispersed in the three-dimensional basic structure. Using such microporous particles, a structure based on the three-dimensional basic structure may be formed. Specifically, a new structure different from the three-dimensional structure of the gel-like compound may be formed. Thus, the finally obtained low refractive index layer (porous structure) may have a refractive index as low as, for example, an air layer. Furthermore, by chemically bonding the microporous particles to each other, the three-dimensional basic structure may be fixed, and the finally obtained low refractive index layer (porous structure) may have sufficient strength. Details of the specific configuration and formation method of the low refractive index layer (porous structure) are described, for example, in International Publication No. 2019 / 151073. The disclosure of this publication is incorporated herein by reference.

[0085] The coating thickness of the coating liquid can be set according to the thickness desired for the low refractive index layer. The heating temperature of the coating film (coating liquid) is, for example, 20°C or higher, preferably 50°C or higher. On the other hand, the heating temperature of the coating film (coating liquid) is, for example, 200°C or lower, preferably 150°C or lower. The heating time of the coating film (coating liquid) is, for example, 10 seconds or longer. On the other hand, the heating time of the coating film (coating liquid) is, for example, 24 hours or shorter, preferably 1 hour or shorter, more preferably 30 minutes or shorter, and even more preferably 10 minutes or shorter.

[0086] A coating film that forms a void structure, which is a precursor of a porous layer (void layer), is formed on a substrate. The following describes the case where the particles are pulverized gel compounds. However, a coating film can be formed in the same way when the particles are other than pulverized gel compounds. The reason why a void structure suitable for the coating film is formed when the particles are pulverized gel compounds is presumed to be, for example, as follows. However, this presumption does not limit the method for forming a low refractive index layer.

[0087] Since the above-mentioned particles (porous particles) are made by pulverizing gel silicon compound, the three-dimensional structure of the gel silicon compound before pulverization is dispersed in the three-dimensional basic structure.For example, by spraying the crushed material of gel silicon compound onto a substrate, the precursor of the porous structure based on the three-dimensional basic structure is formed.In other words, according to the above-mentioned method, a new porous structure (three-dimensional basic structure) is formed by spraying the crushed material, which is different from the three-dimensional structure of the gel silicon compound.Therefore, in the low refractive index layer obtained finally, for example, it can realize a low refractive index that functions as the same as an air layer.

[0088] In one embodiment, forming the low refractive index layer may further include a step of heating and drying the coating film on the substrate. The heating temperature is, for example, 60°C or higher, preferably 70°C or higher, and more preferably 80°C or higher, and, for example, 200°C or lower, preferably 120°C or lower, and more preferably 100°C or lower. The heating time is not particularly limited as long as the coating film can be sufficiently dried. In one embodiment, a crosslinking reaction occurs between multiple particles contained in the coating film in this step. As a result, the three-dimensional basic structure is fixed. As a result, the finally obtained low refractive index layer can maintain sufficient strength and flexibility despite having a void structure.

[0089] C-4.Resin layer The resin layer may be the same as the resin layer in the laminate film, and therefore the description of the resin layer in section B-3 of the laminate film may be applied to the resin layer.

[0090] In the optical member 200 of the illustrated example (for example, FIG. 4A), the resin portions 21 constituting the resin layer 20 are arranged spaced apart on the surface (the pressure-sensitive adhesive layer 10 side) of the low refractive index layer 60. The resin portions 21 are not part of the low refractive index layer 60. Because the resin portions are arranged spaced apart, the low refractive index layer can have a pattern shape relative to the pattern shape formed by the resin portions.

[0091] In an optical element 201 according to one embodiment of the present invention, the resin portion 21 permeates the voids in the low-refractive-index layer 60. Specifically, the resin portion 21 may permeate, for example, the voids in the low-refractive-index layer 60. In an optical element according to an embodiment of the present invention, the resin portion may be formed in the thickness direction of the low-refractive-index layer. The resin portion 21 may be formed on the surface of the low-refractive-index layer 60 (see FIG. 4A), may be formed partway through the thickness direction of the low-refractive-index layer 60 (not shown), or may be formed throughout the entire thickness direction of the low-refractive-index layer 60 (see FIG. 4B). The resin portion may be a dried product, a semi-cured product, or a cured product of the resin composition, and more preferably is a cured product of the resin composition.

[0092] C-5. Adhesive layer The pressure-sensitive adhesive layer may be the same as the pressure-sensitive adhesive layer in the laminate film, and therefore the explanation of the pressure-sensitive adhesive layer in section B-1 of the laminate film may be applied to the pressure-sensitive adhesive layer.

[0093] In the optical member according to the embodiment of the present invention, as described above, the pressure-sensitive adhesive layer is disposed on, for example, the low refractive index layer. In one embodiment, the optical member 200 is configured by peeling off the release liner 30 of the laminated film 100 (see FIG. 3) and bonding the pressure-sensitive adhesive layer 10 of the laminated film 100 to the low refractive index layer 60 (see FIG. 4A). Furthermore, when the optical member according to the embodiment of the present invention is used in a device such as an image display device or a lighting device, for example, the substrate of the optical member is peeled off from the pressure-sensitive adhesive layer, and the pressure-sensitive adhesive layer is bonded to a light-guiding member such as a light-guiding layer.

[0094] C-6. Other configurations Optical members according to embodiments of the present invention may have configurations other than those described above. For example, an optical member 200 (201) according to one embodiment has a release liner 40 on the side of the pressure-sensitive adhesive layer 10 opposite the low refractive index layer 60 (see FIGS. 4A and 4B). The release liner 40 is the same as the second release liner described in section B-4 of the laminate film above. Therefore, the explanations of the release liners described in sections B-2 and B-4 of the laminate film above can be used for the release liner. In optical members according to embodiments of the present invention, the release liner can be used to protect the pressure-sensitive adhesive layer until the optical member is used. When the optical member according to the embodiment of the present invention is used in a device such as an image display device or a lighting device, the release liner of the optical member is peeled off and the pressure-sensitive adhesive layer is attached to a light guide member such as a light guide layer. However, the release liner is not an essential component of the optical member according to the embodiment of the present invention.

[0095] C-7. Manufacturing methods for optical components An optical element according to an embodiment of the present invention can be produced, for example, by peeling the release liner from the laminate film, placing a pressure-sensitive adhesive layer on the low refractive index layer of a laminate including a substrate and a low refractive index layer, and, if necessary, drying the resin portion, allowing the resin portion to penetrate the low refractive index layer, and / or curing the resin portion. The following describes in detail the method for producing an optical element according to an embodiment of the present invention. As described above, the optical element according to an embodiment of the present invention may employ the laminate film according to the above embodiment, and therefore may include all or part of the method for producing the laminate film according to the above embodiment. Therefore, in the method for producing an optical element according to an embodiment of the present invention, the description common to the method for producing the laminate film will be omitted as appropriate, and the description in Section B-5 above will be used.

[0096] For example, first, a laminate film that has been stored in a roll shape is unwound. The unwound size may be any appropriate size depending on the application. In this way, a long laminate film is prepared. Note that the roll-shaped laminate film when unwound and / or the unwound long laminate film may be cut to a desired size to form a sheet of laminate film. Next, the release liner is peeled off from the unwound laminate film. This exposes the pressure-sensitive adhesive layer and resin layer (resin portion) of the laminate film. This laminate film, i.e., the laminate film comprising the support member, pressure-sensitive adhesive layer, and resin layer, is also referred to as a second laminate.

[0097] 5, the adhesive layer 10 and resin layer 20 (resin portion 21) of the second laminate 120 are superimposed on and bonded to the low refractive index layer 60 of a laminate 130 (hereinafter also referred to as a third laminate) including a substrate 50 and a low refractive index layer 60. That is, the adhesive layer 10 and resin layer 20 (resin portion 21) of the second laminate 120 are disposed on the low refractive index layer 60 of the third laminate 130. The low refractive index layer 60 of the third laminate 130 may also be disposed on the adhesive layer 10 and resin layer 20 of the second laminate 120. A stack in which the third stack is disposed on the second stack and / or a stack in which the second stack is disposed on the third stack may be referred to as a fourth stack. An optical element according to an embodiment of the present invention may include the fourth stack. Alternatively, the pressure-sensitive adhesive layer, the resin layer, and the low-refractive index layer may be laminated together, so that the resin portions arranged at a distance from each other may be transferred to the low-refractive index layer. However, the resin portions may not be transferred to the fourth laminate.

[0098] In one embodiment, the resin portion is infiltrated into the low refractive index layer of the fourth laminate. By infiltrating the resin portion into the low refractive index layer, the resin portion can be formed in the thickness direction of the low refractive index layer. Preferably, the resin portion may be formed throughout the entire thickness direction of the low refractive index layer (see FIG. 4B). Any appropriate method can be used to infiltrate the resin portion into the low refractive index layer. For example, the infiltration method includes infiltrating the resin layer (resin portion) under its own weight at room temperature and normal pressure, and / or infiltrating by applying pressure under any appropriate conditions, and / or infiltrating by heating. When heating, any appropriate heating conditions can be used as long as the resin portion does not harden. For example, the heating temperature can be about 100°C, and the heating time can be 1 minute or more and 10 minutes or less. In this manner, an optical member according to an embodiment of the present invention may be fabricated.

[0099] In one embodiment, the resin portion of the fourth laminate is dried. Specifically, volatile components that may be contained in the resin portion of the fourth laminate are evaporated under any appropriate conditions. The resin portion may be heated to evaporate the volatile components. When heating, the heating conditions for drying can be adjusted to an appropriate heating temperature and heating time based on the composition of the resin composition, etc. The heating temperature is, for example, 80°C or higher and 150°C or lower. The heating time is, for example, 1 minute or higher and 1 hour or lower. This makes it possible to obtain an optical element in which the resin layer contains a dried product of the resin composition.

[0100] The resin portion in the fourth laminate may be dried before or after the resin portion is infiltrated into the low refractive index layer. When the resin portion is heated before the resin portion is infiltrated into the low refractive index layer, it is preferably heated at a temperature equal to or lower than the temperature at which the resin portion hardens. The heating conditions can be adjusted appropriately based on the composition of the resin composition, etc. The heating temperature is, for example, 80°C or higher and 150°C or lower. The heating time is, for example, 1 minute or higher and 1 hour or lower. This makes it possible to obtain an optical element in which the resin layer contains a dried and / or semi-cured resin composition.

[0101] In one embodiment, the resin portion is allowed to penetrate the low refractive index layer and then cured. The resin portion is preferably cured by irradiating the resin layer of the fourth laminate with light. Any appropriate light may be used for the irradiated light depending on the composition of the resin composition, the type and content of the resin material, the type of additive, etc. The light may be, for example, ultraviolet light. Similarly, any appropriate light irradiation conditions may be used. This allows for the production of an optical element in which the resin layer contains a cured product of the resin composition.

[0102] In one embodiment, the resin portion may be cured by a combination of curing by light irradiation and curing by heat. Curing by light irradiation (photocuring) may be the same as described above. The heating conditions for curing by heat (thermal curing) may be any appropriate heating temperature and / or heating time. The heating temperature is, for example, 60°C or higher and 150°C or lower. The heating time is, for example, 1 minute or higher and 60 minutes or lower. Furthermore, when the resin layer is heated, the resin portion (substantially the resin composition) that has permeated the low refractive index layer may be crosslinked inside the low refractive index layer. This may allow the resin portions arranged at a distance to be transferred to the low refractive index layer. In this manner, an optical element according to one embodiment of the present invention may be fabricated.

[0103] The method for producing an optical member according to an embodiment of the present invention is not limited to the above-described method, and may include any appropriate steps as long as the effects of the present invention are not impaired.

[0104] The long optical member obtained by the above manufacturing method can be cut into any suitable size to form a sheet-like optical member of appropriate size. [Example]

[0105] The present invention will be specifically explained below with reference to examples, but the present invention is not limited to these examples.

[0106] (1) Ink height and ink diameter before pressure application The shape of the coating (resin layer) on the test piece of the laminated film before pressure application (hereinafter also referred to as the "pre-pressure test piece") was observed using a laser microscope (Keyence Corporation, Model No. VK-X1000). The image obtained by observation was processed to calculate the ink height and ink diameter. (2) Ink height, ink diameter, and ink shape change rate after pressure application The pre-pressure test piece was cut to a thickness of 90 μm, and two PET films (film thickness: 38 μm, adhesive layer thickness: 10 μm) were attached to both sides of the thickness direction of the cut pre-pressure test piece. The test piece was then sandwiched and pressurized at a temperature of 25°C and a pressure of 0.40 MPa for 13 hours. This resulted in a test piece of the laminated film after pressing (hereinafter also referred to as the post-pressure test piece). The shape of the coating film (resin layer) on the post-pressure test piece was observed using a laser microscope (Keyence Corporation, model number VK-X1000). The image obtained by observation was processed to calculate the ink height and ink diameter. The value obtained by dividing the ink diameter of the test piece after pressure by the ink diameter of the test piece before pressure was taken as the "ink shape change rate." (3) Pressure resistance From the above-mentioned ink shape change rate and the results of the ink image after pressure application, the pressure resistance of the laminated films of the Examples and Comparative Examples was evaluated based on the following criteria. A (good): The ink shape change rate was 2.0 times or less, and no ink swelling was observed in the image. B (medium): The ink shape change rate was 3.0 times or less, and no ink swelling was observed in the image. C (poor): The ink shape change rate was more than 3.0 times, and swelling and / or spreading of the ink was observed in the image.

[0107] [Production Example 1] Preparation of adhesive and production of adhesive layer An adhesive layer was prepared according to the following procedures (i) to (iii). (i) Preparation of (meth)acrylic polymer (A) solution A monomer mixture containing 79.5 parts of butyl acrylate, 15 parts of N-acryloylmorpholine, 5 parts of acrylic acid, and 0.5 parts of 4-hydroxybutyl acrylate was added to a four-neck flask equipped with a stirrer, thermometer, nitrogen gas inlet tube, and condenser. Next, 0.1 parts of a polymerization initiator (2,2'-azobisisobutyronitrile) and 70 parts of ethyl acetate were added to 100 parts of the monomer mixture, and nitrogen gas was introduced while stirring to replace the atmosphere in the flask. The liquid temperature in the flask was then raised to approximately 55°C, and the polymerization reaction was allowed to proceed for 2 hours while maintaining the temperature. This yielded a solution of (meth)acrylic polymer (A) with a weight average molecular weight (Mw) of 3,000,000 and a polydispersity index (Mw / Mn) of 2.5. (ii) Preparation of (meth)acrylic pressure-sensitive adhesive composition A solution of an acrylic pressure-sensitive adhesive composition (pressure-sensitive adhesive 1) was prepared by mixing 0.2 parts of an isocyanate crosslinking agent ("Coronate L" manufactured by Nippon Polyurethane Industry Co., Ltd.: an adduct of trimethylolpropane and tolylene diisocyanate) and 0.2 parts of an epoxy crosslinking agent ("Tetrad C" manufactured by Mitsubishi Gas Chemical Company, Inc.: 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane) with 100 parts of the solid content of the solution of (meth)acrylic polymer (A) described in (i) above. (iii) Preparation of adhesive layer A solution of the acrylic pressure-sensitive adhesive composition (ii) above was applied to one side of a polyethylene terephthalate (PET) film (Mitsubishi Chemical Polyester Film Corporation, product name "MRF38") that had been surface-treated with a silicone-based release agent, so that the thickness of the pressure-sensitive adhesive layer after drying would be 10 μm, and the coating was dried at 155° C. for 1 minute. This produced a laminate (PET film / pressure-sensitive adhesive layer) comprising a pressure-sensitive adhesive layer on the PET film. The storage modulus of the adhesive layer is 1.1 x 10 5 The storage modulus was determined by reading the value at 23°C when measurements were performed in accordance with JIS K7244-1 at a frequency of 1 Hz in the range of -50°C to 150°C at a temperature increase rate of 5°C / min. The nanoindentation hardness of the pressure-sensitive adhesive layer was 1.08 MPa. The nanoindentation hardness was measured by the AFM force curve method in accordance with ISO 14577, using a nanoindenter (manufactured by Oxford Instruments, model number "MFP-3D-SA") to press the indenter 2000 nm into the laminate (dimensions: width 10 mm, length 10 mm, thickness 48 mm).

[0108] [Example 1] As a laminate (first laminate) of a support member and an adhesive layer, the PET film / adhesive layer of Production Example 1 above, the release liner was the release liner 1 described below, and as a resin composition (ink) for the resin layer, an ink containing the resin material 1 described below was prepared. Ink was applied onto the adhesive layer of the first laminate. The application was performed by inkjet printing as follows. That is, first, ink was injected into the inlet of the inkjet device. Then, the first laminate was placed below the discharge port of the inkjet device with the adhesive layer facing the discharge port. Next, ink was ejected from the ejection port of the inkjet device so that the ejected ink droplets had the "ink height" and "ink diameter" before pressure application listed in Table 1. In this way, a resin layer, i.e., a pattern made of the resin portion (ink), was formed on the adhesive layer. Next, the first laminate was heated. By heating, the resin portion was dried. Next, a release liner was placed on the pressure-sensitive adhesive layer on which the resin layer was placed, and the release liner was temporarily attached. In this way, a laminated film (a laminated film before pressure application) was produced. The obtained laminated film was subjected to the measurement and evaluation described above in (1). Furthermore, the obtained laminated film was pressed under the conditions of (2) above to prepare a test piece after pressing, which was then subjected to the evaluations of (2) and (3) above.

[0109] [Examples 2 to 7 and Comparative Examples 1 to 3] A laminated film (laminated film before pressurization and laminated film after pressurization) was produced in the same manner as in Example 1, except that the ink height and ink diameter before pressurization of the ink containing resin material 1 were changed to the values ​​shown in Table 1. The obtained laminated film was subjected to the same evaluation as in Example 1.

[0110] The materials shown in Table 1 are as follows: (resin material) Resin material 1: Urethane-based photocurable resin (manufactured by Daicel Allnex: product name KRM8904. Resin components: urethane acrylate. Thickness: 1-4 μm.) dissolved in the solvent diethylene glycol ethyl methyl ether (EDM) together with the initiator 1-hydroxycyclohexyl phenyl ketone to a solids concentration of 12-35% by weight. (Release liner) Release liner 1: Mitsubishi Chemical Polyester Film Corporation: Product name "MHE38". Thickness: 38 μm.

[0111] [Table 1]

[0112] As is clear from Table 1, according to the examples of the present invention, the shape change rate of the ink diameter (ink shape change rate) was 3.0 times or less, and it was found that the pressure resistance was excellent. In other words, according to the examples of the present invention, deformation of the resin part was suppressed, and as a result, a laminated film that can suppress shape change of the ink pattern in the resin layer was obtained. [Industrial Applicability]

[0113] The laminate film according to the embodiment of the present invention can be suitably used to produce an optical element, and in particular, the laminate film according to the embodiment of the present invention can be suitably used to produce an optical element having a light distribution function. [Explanation of symbols]

[0114] 10 adhesive layer 20 Resin layer 21 Resin part 30 Release liner 40 Supporting member (release liner) 50 Base material 60 Low refractive index layer 100 Laminated Film

Claims

1. A pressure-sensitive adhesive layer, a resin layer, and a release liner are provided in this order, the resin layer includes resin portions arranged on the pressure-sensitive adhesive layer at a distance from each other, The equivalent diameter of the resin portion is 150 μm or less. Laminated film.

2. The laminate film according to claim 1 , wherein the resin portion comprises at least one selected from the group consisting of a dried product, a semi-cured product, and a cured product of a resin composition.

3. The laminate film according to claim 2 , wherein the resin composition contains a photocurable resin.

4. The laminate film according to claim 3 , wherein the photocurable resin contains at least one resin selected from the group consisting of urethane (meth)acrylate, epoxy (meth)acrylate, and polyester (meth)acrylate.

5. The laminate film according to claim 1, wherein the pressure-sensitive adhesive layer has a nanoindentation hardness of 0.5 MPa or more when measured in accordance with ISO 14577 using a nanoindenter by pressing an indenter 2000 nm inward.

6. The laminated film according to claim 1 , wherein the ratio of the area of ​​the resin portion to the total area of ​​the pressure-sensitive adhesive layer is 60% or less.

7. A laminate including a support member and a pressure-sensitive adhesive layer, and resin portions constituting a resin layer are disposed on the pressure-sensitive adhesive layer so as to be spaced apart from each other; and and disposing a release liner that covers the laminate and the resin portion. A method for manufacturing a laminated film.

8. The method for producing a laminated film according to claim 7 , further comprising heating the resin portion after the resin portion is disposed.

9. The method for producing a laminated film according to claim 7 , further comprising winding the film into a roll after disposing the release liner.

Images