JP2013001007A - Laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate capable of suppressing damage of a minute irregular structure and dust contamination caused by the damage and suppressing decline in optical performance before and after peeling of a protective film.SOLUTION: The laminate (1) includes: a minute structure layer (12) having an irregular structure (12a) formed on the surface thereof; and the protective film (13) installed on the minute structure layer (12) and coming into contact with recesses and projections of the irregular structure (12a) to cover the irregular structure (12a). In the minute structure layer (12), a pitch between the projections adjacent to each other is equal to or lower than a wavelength of visible light. The protective film (13) includes a water insoluble resin material, and adhesive strength to the minute structure layer (12) after peeling from the minute structure layer (12) is 0.01 N/cm or less.

Description

  The present invention relates to a laminate having a fine structure layer having a fine concavo-convex structure formed on the surface, and more particularly, to a laminate having a protective film for protecting the fine structure layer.

  In recent years, antireflection films have been used to protect the surface of displays and improve the power generation efficiency of solar cells. The antireflection film has a fine structure layer having a fine concavo-convex structure formed on the surface, and the fine structure layer suppresses reflection of light. Such a microstructure layer is relatively weak to external stress, and the concavo-convex structure may be damaged by an impact during construction or transportation. For this reason, in the antireflection film, the concavo-convex structure of the fine structure layer is used after the production of the antireflection film and immediately before use by using an adhesive sheet or the like on which a fine adhesive layer that can be repeatedly peeled is formed.

  However, the pressure-sensitive adhesive sheet lacks adhesive strength and stability over time of the pressure-sensitive adhesive component, so that the fine structure layer is contaminated due to the adhesive residue of the peeled fine pressure-sensitive adhesive layer, and the pressure-sensitive adhesive sheet tends to be unpeelable from the fine structure layer. There is. In particular, in the case of protecting a fine structure layer having a fine concavo-convex structure with a height of 1 μm or less with a pressure-sensitive adhesive sheet, contamination due to adhesive residue or a case where the pressure-sensitive adhesive sheet cannot be peeled is remarkable. It is extremely difficult to achieve both reduction of adhesive residue and stable protection of the microstructure layer over a long period of time. In order to stably protect the fine structure layer over a long period of time, a fine structure film laminate (see, for example, Patent Document 1) having a protective film provided by applying a water-soluble resin on the concavo-convex structure, or a substrate A molded body with a protective film that protects the concavo-convex structure in a non-contact manner by providing an adhesive layer outside the concavo-convex structure forming region of the film and sticking a protective film on the adhesive layer so as to cover the concavo-convex structure has been proposed. (For example, refer to Patent Document 2).

JP 2010-17922 A JP 2010-120348 A

  However, in the microstructured film laminate described in Patent Document 1, it is necessary to remove the protective layer using a solvent in order to peel the protective film from the protected surface. For this reason, when a protective film is provided on a fine concavo-convex structure such as a moth-eye structure, it is difficult to completely remove the protective film residue, and after incorporation into a system such as a display or a solar cell, the solvent is removed. There arises a problem that it is impossible to remove the protective layer by itself. In addition, since a water-soluble resin is used, there is a problem in the stability of the protective layer depending on the temperature environment and humidity environment during storage.

  Furthermore, in the molded article with a protective film described in Patent Document 2, the protective film is attached to the adhesive layer provided outside the concavo-convex structure forming region, so that the concavo-convex structure is rubbed with the protective film, There is a problem that dust generation contamination occurs and the function as a protective film is not always sufficiently obtained.

  The present invention has been made in view of the above points, and is a laminate capable of suppressing breakage of a concavo-convex structure of a fine structure layer and dusting contamination accompanying breakage, and suppressing deterioration of optical performance before and after peeling of a protective film. The purpose is to provide.

  As a result of intensive studies, the present invention provides protection by providing a protective film containing a water-insoluble resin material and having substantially no adhesive force with the microstructure layer on the concavo-convex structure of the microstructure layer. The present inventors have found that a film can be easily peeled off at the interface of the fine structure layer, and a laminate capable of suppressing a decrease in optical performance before and after peeling of the protective film can be realized.

  That is, the laminate of the present invention includes a fine structure layer having a concavo-convex structure formed on a surface thereof, and a protective film that is provided on the fine structure layer and contacts the concave and convex portions and covers the concavo-convex structure. In the fine structure layer, the pitch between adjacent convex portions is equal to or less than the wavelength of visible light, and the protective film contains a water-insoluble resin material, and the fine structure after peeling from the fine structure layer The adhesive strength to the layer is 0.01 N / cm or less.

  According to this configuration, the protective film comes into contact with the concave and convex portions and covers the concave and convex structure of the fine structure layer, so that damage to the concave and convex structure of the fine structure layer and dust generation contamination associated with the damage can be suppressed. Further, since the contact area between the concave portion and the convex portion of the concavo-convex structure of the protective film and the fine structure layer is increased, even if the adhesive force between the protective film and the fine structure layer is small, the protective film and It becomes possible to bond the microstructure layer. As a result, the protective film can be easily peeled off from the fine structure layer, and contamination such as adhesive residue on the fine difference structure layer before and after peeling can be suppressed, and reduction in optical performance can be suppressed.

  In the laminate of the present invention, the thickness of the protective film is 5 μm to 200 μm, and the peeling force for peeling the protective film from the microstructure layer is 0.02 N / 25 mm or more and 4 N / 25 mm or less, and It is preferable that the peeling force for peeling the protective film from the microstructure layer is smaller than the breaking strength of the protective film.

  In the laminate of the present invention, the protective film is made of a group consisting of water-insoluble nylon, ethylene vinyl acetate, fluorine, acrylic, polyurethane, polyurea, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide, and acrylic. It is preferable to contain at least one selected resin as a main component.

  In the laminate of the present invention, the protective film is made of styrene-ethylene-butylene-styrene, styrene-butadiene-butylene-styrene, styrene-ethylene-propylene-styrene, styrene-butadiene-styrene, and styrene-isoprene-styrene. It is preferable to include a copolymer containing at least one block structure selected from the group consisting of a molecular chain in the molecular chain, or a thermoplastic elastomer of a modified form of the copolymer.

  In the laminate of the present invention, it is preferable that the protective film includes a polyurethane and / or a urea resin using an aliphatic diisocyanate containing a urea bond and a glycol having 4 or more carbon atoms.

  The laminate of the present invention further comprises a base material provided on the fine structure layer and containing a thermoplastic resin, the fine structure layer contains a photocurable resin, and the base material, the fine structure layer, Is preferably larger than the relationship of the peeling force for peeling the protective film from the microstructure layer.

  In the laminated body of this invention, it is preferable to comprise the adhesion layer provided on the said base material without passing through the said microstructure layer, and the release film provided on the said adhesion layer.

  In the laminated body of this invention, it is preferable that the said base material has a pair of main surface, and the said microstructure layer and the said protective film were laminated | stacked in this order on the said both main surfaces of a pair, respectively.

  ADVANTAGE OF THE INVENTION According to this invention, the laminated body which can suppress the dust generation contamination accompanying the breakage | corrugation of a fine structure layer and damage, and also can suppress the fall of optical performance before and behind peeling of a protective film is realizable.

It is a cross-sectional schematic diagram which shows an example of the laminated body which concerns on this Embodiment. It is a cross-sectional schematic diagram which shows the other example of the laminated body which concerns on this Embodiment. It is a cross-sectional schematic diagram which shows another example of the laminated body which concerns on this Embodiment. It is a cross-sectional schematic diagram which shows another example of the laminated body which concerns on this Embodiment. It is a cross-sectional SEM photograph of the laminated body which concerns on this Embodiment. It is a figure which shows the reflectance before and behind formation of the protective film of the laminated body which concerns on Example 1. FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited to the following embodiment, It can be implemented in various deformation | transformation within the range of the summary.

1A and 1B are schematic cross-sectional views of a laminate according to an embodiment of the present invention.
As shown to FIG. 1A, the laminated body 1 which concerns on this Embodiment is the base material 11, the fine structure layer 12 in which the uneven structure 12a was formed in the surface provided on this base material 11, and this fine structure layer 12 and a protective film 13 that contacts the concave and convex portions of the concave-convex structure 12a of the microstructure layer 12 and covers the concave-convex structure 12a.

  The base material 11 has a pair of opposing main surfaces, and the microstructure layer 12 is provided on one main surface. The concavo-convex structure 12a of the microstructure layer 12 includes a plurality of continuous recesses and protrusions extending in the surface of the microstructure layer 12 (left and right direction and depth direction in FIG. 1), and the pitch P between adjacent protrusions P Is provided to be equal to or less than the wavelength of visible light. The protective film 13 is provided in close contact with the recesses and projections so as to follow the recesses and projections extending into the surface of the microstructure layer 12, and is filled in the recesses of the relief structure 12 a of the microstructure layer 12. Is done. Further, the protective film 13 includes a water-insoluble resin material and has substantially no adhesiveness with the fine structure layer 12. In this laminated body 1, since the protective film 13 enters into the concave portion of the concavo-convex structure 12a of the fine structure layer 12, the contact area between the protective film 13 and the fine structure layer 12 increases, and the protective film 13 and the fine structure The layer 12 can be bonded. In addition, since the adhesive force between the protective film 13 and the fine structure layer 12 is small, the concavo-convex structure 12a of the fine structure layer 12 when the protective film 13 is peeled from the fine structure layer 12, the destruction of the protective film 13, In addition, it is possible to suppress the remaining of the material constituting the protective film 13.

  The fact that the protective film 13 is not substantially sticky to the fine structure layer 12 means that the fine film after the fine structure layer 12 and the protective film 13 are laminated and then peeled off from the fine structure layer 12. It means that the substantial adhesive force between the structural layer 12 and the protective film 13 is 0.01 N / cm or less. Even if the substantial adhesive force is 0.01 N / cm or less, if the protective film 13 is in contact with the concave and convex portions of the concavo-convex structure 12 a on the fine structure layer 12, the molecules of the protective film 13 and the fine structure layer 12 It is possible to maintain a sufficiently adhered state by an interstitial force. Further, when the concavo-convex structure 12a is miniaturized, it is considered that the increase in the surface area of the fine structure layer 12a also contributes to the adhesion between the protective film 13 and the fine structure layer 12. In addition, the measurement of the adhesive force with the fine structure layer 12 of the protective film 13 after peeling is performed so that the peeled surfaces of the protective film 13 peeled in an environment of 23 ° C. and 50% RH face each other again. 13 and the microstructure layer 12 can be pressed together with a weight within a range where the shape of the microstructure does not break, and measured using an adhesive tape 90-degree peel test jig based on JIS Z1528.

  Note that the protective film 13 once peeled off from the fine structure layer 12 cannot be brought into close contact with the surface of the fine structure layer 12 where the uneven structure 12a is formed. This is presumably because contact failure between the protective film 13 and the recesses and protrusions of the concavo-convex structure 12a on the fine structure layer 12 occurs. As the protective film 13, it is preferable to use a resin material soluble in an organic solvent. As shown in FIG. 1B, the laminated body 1 may not necessarily include the base material 11 as long as the microstructure layer 12 and the protective film 13 are laminated (see FIG. 1B). .

  FIG. 2 is a diagram illustrating another configuration example of the laminated body according to the present embodiment. In the laminated body 1 shown in the same figure, the structure shown in FIG. 1 is further provided with an adhesive layer 14 and a release film 15 provided on the adhesive layer 14. In this laminated body 1, the fine structure layer 12 and the protective film 13 are laminated | stacked in this order on one main surface of the base material 11, and the adhesion layer 14 and the release film 15 are on the other main surface of the base material 11. They are stacked in this order. With this configuration, it is possible to easily attach the base material 11 to an interface portion with air such as a display, a show window panel, and various optical elements by a laminating method or a pressing method. As a result, functions such as an antireflection function, super hydrophilicity, and super water repellency can be added to the laminate 1. In the laminate 1 shown in FIG. 2, the fine structure layer 12 and the protective film 13 are configured in the same manner as the laminate 1 shown in FIG. Moreover, in the example shown in FIG. 2, although the fine structure layer 12 was provided in one main surface of the base material 11, and the structure which provided the release film 15 via the adhesion layer 14 in the other main surface was demonstrated, The adhesive layer 14 and the release film 15 are not necessarily provided on the other main surface, and may be provided on the end surface of the substrate 11.

  3 and 4 are diagrams showing another configuration example of the laminated body according to the present embodiment. In the laminate 1 shown in FIG. 3, the fine structure layer 12 </ b> A and the protective film 13 </ b> A are laminated in this order on one main surface of the substrate 11, and the fine structure 12 </ b> B and the protection are formed on the other main surface of the substrate 11. The film 13B is laminated in this order. With this configuration, a film-like or sheet-like laminate 1 having excellent transmission performance of 97% or more can be formed. This makes it possible to replace glass and acrylic panels used in conventional show windows, wall clocks, lighting fixtures, flashlights, etc., improving visibility, improving transparency, and reducing weight. Can be realized. Furthermore, since it does not break like glass, safety is improved.

  In the laminate 1 shown in FIG. 4, one main surfaces of the pair of base materials 11A and 11B are bonded to each other through the adhesive layer 14, and the fine structure layer 12A and the protective film are formed on the other main surface of the base material 11A. 13A are laminated in this order, and the fine structure layer 12B and the protective film 13B are laminated in this order on the other main surface of the substrate 11B. 3 and 4, the fine structure layers 12A and 12B and the protective films 13A and 13B are configured in the same manner as the stacked body 1 shown in FIG.

  In the laminate 1 according to the present embodiment, the protective film 13 contacts the concave and convex portions of the concave and convex structure of the fine structure layer 12 to cover the concave and convex structure 12a. It is possible to suppress damage and contamination caused by dust. Furthermore, since the protective film 13 contacts the concave and convex portions and covers the concave and convex structure 12a, the protective film 13 is filled in the concave portions of the concave and convex structure 12a of the fine structure layer 12, and the protective film 13 and the fine structure layer 12 are filled. The contact area between the two increases. Thereby, even when the adhesive force between the protective film 13 and the fine structure layer 12 is small, the protective film 13 and the fine structure layer 12 can be bonded, and the protective film from the fine structure layer 12 can be bonded. 13 can be easily peeled off. Further, contamination such as adhesive residue of the fine structure layer 12 before and after peeling of the protective film 13 can be suppressed, and suppression of deterioration in optical performance can be realized. In particular, when the concavo-convex structure 12a of the fine structure layer 12 is a fine concavo-convex structure such as a moth-eye structure, the contact area between the fine structure layer 12 and the protective film 13 is greatly increased, and the above-described effects are remarkable. Expressed.

<Base material>
As a material of the base material 11, an inorganic material such as glass, ceramic, or metal can be used, and can be arbitrarily selected according to the purpose of use or application. Depending on the application, there are cases where light transparency is required and non-transparency is required, and the type can be selected according to the purpose. When light transmittance is required, it is necessary to be transparent in a wavelength region according to the purpose of use, and a transparent resin or glass is preferable, and when flexibility is also required, a transparent resin is more preferable.

  Examples of the material of the substrate 11 include polymethyl methacrylate resin, polycarbonate (hereinafter referred to as PC) resin, polystyrene (hereinafter referred to as PST) resin, cycloolefin (hereinafter referred to as COP) resin, crosslinked polyethylene resin, and polyvinyl chloride resin. Polyarylate (hereinafter referred to as PAR) resin, polyphenylene ether resin, modified polyphenylene ether resin, polyetherimide (hereinafter referred to as PEI) resin, polyether sulfone (hereinafter referred to as PES) resin, polysulfone resin, polyether ketone resin, polyethylene terephthalate ( Hereinafter, PET) resin, polyethylene naphthalate (hereinafter, PEN) resin, polyethylene (hereinafter, PE) resin, polyoxymethylene (hereinafter, POM) resin, polypropylene resin, polybutylene terephthalate resin, aromatic polyester Use organic materials such as thermoplastic resins such as tellurium resin, polyacetal resin, polyamide resin, triacetate cellulose (hereinafter referred to as TAC) resin, UV curable resin such as acrylic resin, epoxy resin, and urethane resin, and thermosetting resin. be able to. Moreover, as a material of the base material 11, polyethylene terephthalate resin, polyethylene naphthalate resin, triacetyl cellulose resin, polycarbonate resin, polymethyl methacrylate resin, acrylic resin, methyl methacrylate-styrene resin, polystyrene resin, cycloolefin type It is preferable to use at least one thermoplastic resin selected from a resin, a polyether sulfone resin, and a polysulfone resin.

  Moreover, as the base material 11, you may use what performed surface treatments, such as a silane coupling agent, primer treatment, and UV treatment, to inorganic substrates, such as glass. When a resin film is used as the substrate 11, there is an advantage that flexibility, workability, productivity, and impact resistance are improved. In the case where a resin material is used as the substrate 11, a material obtained by adding other conventional additives to the resin material as necessary may be used as long as the original purpose is not impaired. For example, organic and inorganic particles, plasticizers, antioxidants, ultraviolet absorbers, antistatic agents, antifogging agents, easy adhesion layers, dyes, and the like can be included. These may be used by directly blending with the resin material, or a layer containing these may be laminated on the substrate 11. Furthermore, as the base material 11, a base material 11 in which an adhesive layer or an interference reduction layer is formed on the base material 11 can also be used.

  Moreover, in order to protect the base material 11 from deterioration factors such as heat, light, and moisture, a resin layer for a gas barrier may be coated on the surface of the base material 11. In many cases used for optical applications, the substrate 11 is required to have transparency. The necessary conditions in this case are (a) transparent in the wavelength region according to the purpose of use, (b) good adhesion to the photocuring resin, (c) a small difference in refractive index from the photocuring resin, ( d) The haze is required to be small. Preferably, (e) excellent mechanical properties and (f) low price are also considered. From the above viewpoint, the base material 11 is preferably a polymethyl methacrylate resin, a PC resin, a COP resin, a PET resin, a PEN resin, a polybutylene terephthalate resin, an aromatic polyester resin, or a TAC resin.

<Microstructure layer>
The microstructure layer 12 includes a photocurable resin, a thermosetting resin, a thermoplastic resin, a sol-gel reaction product, and the like. The fine uneven pattern (uneven structure 12a) of the fine structure layer 12 is formed by a nanoimprint method using a mold. Specific examples of the method include an optical nanoimprint method, a thermal nanoimprint method, a room temperature nanoimprint method, and a casting method. is there. From the viewpoint of facilitating continuous transfer of the fine concavo-convex pattern, the optical nanoimprint method using a photocurable resin is preferable as a method for forming the fine structure layer 12. The fine concavo-convex pattern of the photocurable resin is formed on the transparent resin substrate.

  As the fine structure layer 12, it is preferable that the fine structure layer 12 including the height of the fine uneven pattern has a thickness of 0.01 μm to 20 μm. In order to suppress the occurrence of cracks in the photocurable resin under high temperature and high humidity conditions, the thickness of the microstructure layer 12 is more preferably 10 μm or less. Furthermore, the thickness of the fine structure layer 12 is more preferably 5 μm or less in order to suppress curling due to shrinkage of the curable resin under high temperature and high humidity. The microstructure layer 12 preferably has a thickness of 0.01 μm or more in order to prevent adhesion of the curable resin to the base material 11 and generation of untransferred portions, More preferably, it is 3 μm.

  When the pitch between the convex portions of the concavo-convex structure 12a is arranged at 300 nm or less, the fine structure layer 12 is excellent in optical applications and is particularly suitable as an antireflection film. For example, it is used by being attached to the surface of an object in contact with an air layer such as a liquid crystal display device, a plasma display panel, an electroluminescence display or the like, a lens, a show window, a spectacle lens, or a viewing water tank. Applications other than antireflection include optical waveguide sheets, holograms, condenser lenses, prism sheets, polarized light separation elements, super water-repellent films, super hydrophilic films, cell culture sheets, and the like.

  Although it does not specifically limit as a thermosetting resin, For example, an epoxy resin, a polydimethylsiloxane (PDMS) resin, a fluorine-containing resin etc. are mentioned. In order to improve the releasability from the mold, since it is effective that the surface energy of the resin is small, a silicone-based polydimethylsiloxane resin is preferable, and a fluorine-containing resin having a lower surface energy is more preferable. The thermoplastic resin is not particularly limited, but for example, an acrylic resin, a styrene resin, a cycloolefin resin, and the like are preferable from the viewpoint of transferability. From the viewpoint of releasability, a fluorine-containing resin is also preferable. The sol-gel reactant may be an alkoxysilane compound, an alkyl silicate compound, or the like.

  As the photocurable resin, a radical polymerization resin or a cationic polymerization resin is preferable, a reaction rate is fast, and a radical polymerization resin is preferable from the viewpoint of continuous productivity. Moreover, in order to improve the reactivity to the deep part of a fine uneven | corrugated pattern, you may be a photocurable resin which mixed the cationic polymerization resin with a long reaction lifetime with the radical polymerization resin. The cationic polymerization type photocurable resin is preferably a monomer having a polymerizable functional group having an epoxy group, a vinyloxy group, an oxetanyl group, an oxazolyl group, or the like.

  Hereinafter, the radical polymerization type photocurable resin will be described in detail. A photocurable resin contains one or more monomers (hereinafter referred to as bifunctional or higher acrylates and / or methacrylates) containing two or more acrylic groups and / or methacrylic groups in one molecule. It is. Examples of monomers include trimethylolpropane triacrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, pentaerythritol triacrylate, propoxylated glyceryl triacrylate, pentaerythritol tetraacrylate, ethoxylated pentaerythritol tetra Acrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, tris (2-hydroxyethyl) isocyanurate triacrylate, trisacryloyloxyethyl phosphate, trifunctional or higher polyester acrylate oligomer, trifunctional or higher Urethane acrylate oligomer, trifunctional Epoxy acrylate oligomer above, trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane trimethacrylate, propoxylated trimethylolpropane trimethacrylate, pentaerythritol trimethacrylate, propoxylated glyceryl trimethacrylate, pentaerythritol tetramethacrylate, Ethoxylated pentaerythritol tetramethacrylate, ditrimethylolpropane tetramethacrylate, dipentaerythritol pentamethacrylate, dipentaerythritol hexamethacrylate, tris (2-hydroxyethyl) isocyanurate trimethacrylate, trismethacryloyloxyethyl phosphate, Urethane diacrylate, trifunctional or higher Polyester methacrylate oligomer, trifunctional or higher urethane methacrylate oligomer, 3 but 1 or more, such as di- or higher functional epoxy methacrylate oligomer include, but are not limited to. Here, an ethoxylated and propoxylated monomer means a monomer containing one or more ethoxy groups and / or propoxy groups in the range of 1 equivalent to 20 equivalents per monomer molecule. Point to. Among these monomers, trimethylolpropane triacrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, ethoxylated trimethylolpropane trimethacrylate, propoxylated trimethylol Propane trimethacrylate is preferred because it has a good balance of physical properties. Among these, a photocurable resin using trimethylolpropane triacrylate or trimethylolpropane trimethacrylate is particularly preferable because of its excellent releasability from the mold after photoreaction.

  As a photocurable resin, the thing containing the 1 or more types of monomer which contains the 2 or more acrylic group and / or methacryl group in 1 molecule as mentioned above in arbitrary ranges may be sufficient. When the content of 3 or more acrylic groups and / or methacrylic groups is 20% by mass or more, a relatively strong molded product can be obtained, and a high crosslinking density can be obtained, resulting in bleed out from the molded product. Degree oligomer by-product and bleed-out can be minimized.

  As a photocurable resin, in addition to the above-mentioned monomer, another monomer may be blended for the purpose of adjusting viscosity and adjusting various physical properties of the cured product. Although there is no restriction | limiting in particular as a monomer, Since it is necessary to adjust the viscosity of photocurable resin, it is also preferable to use in combination with a monomer and an oligomer.

  Specific examples of monomers and oligomers that can be used include methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, 2-ethylhexyl acrylate, isodecyl acrylate, isoamyl acrylate, and n-lauryl acrylate. , Isomyristyl acrylate, stearyl acrylate, n-butoxyethyl acrylate, butoxydiethylene glycol acrylate, methoxytriethylene glycol acrylate, methoxypolyethylene glycol acrylate, tripropylene glycol diacrylate, tetraethylene glycol diacrylate, caprolactone acrylate, cyclohexyl acrylate, tetrahydrofurfuryl Acrylate, benzy Acrylate, phenoxyethyl acrylate, isobornyl acrylate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, dicyclopentanyl acrylate, 2-hydroxyethyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxypropyl acrylate, diethylaminoethyl acrylate , Dimethylaminoethyl acrylate quaternized product, acrylic acid, 2-acryloyloxyethyl succinic acid, 2-acryloyloxyethyl hexahydrophthalic acid, 2-acryloyloxyethyl phthalic acid, 2-acryloyloxyethyl 2-hydroxy Ethyl phthalic acid, neopentyl glycol acrylic acid benzoate, 2-acryloyloxyethyl 2-hydroxypropyl phthalate, glycidyl Acrylate, 2-acryloyloxyethyl acid phosphate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, PEG # 200 diacrylate, PEG # 400 diacrylate, PEG # 600 diacrylate, 1,4-butanediol Diacrylate, neopentyl glycol diacrylate, 3-methyl-1,5-pentanediol diacrylate, 2-butyl-2-ethyl-1,3-propanediol diacrylate, 1,6-hexanediol diacrylate, 1, 9-nonanediol diacrylate, 1,10-decanediol diacrylate, glycerin diacrylate, 2-hydroxy-3-acryloyloxypropyl acrylate, bisphenol A-EO adduct diacrylate, trifluoroethyl acrylate, tetrafluoropentyl acrylate, octafluoropentyl acrylate, perfluorooctyl ethyl acrylate, nonylphenol-EO adduct acrylate, dimethylol tricyclodecane diacrylate, trimethylol propane acrylic acid Benzoic acid ester, hydroxypivalic acid neopentyl glycol diacrylate, tetrafurfuryl alcohol oligoacrylate, ethyl carbitol oligoacrylate, 1,4-butanediol oligoacrylate, 1,6-hexanediol oligoacrylate, trimethylolpropane oligoacrylate, Pentaerythritol oligoacrylate, pentamethylpiperidyl acrylate, tetramethyl Peridyl acrylate, paracumylphenol-EO modified acrylate, N-acryloyloxyethyl hexahydrophthalimide, isocyanuric acid-EO modified diacrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, 2 -Ethylhexyl methacrylate, isodecyl methacrylate, isoamyl methacrylate, n-lauryl methacrylate, isomyristyl methacrylate, stearyl methacrylate, n-butoxyethyl methacrylate, butoxydiethylene glycol methacrylate, methoxytriethylene glycol methacrylate, methoxypolyethylene glycol methacrylate, tripropylene glycol dimethacrylate, Te Raethylene glycol dimethacrylate, caprolactone methacrylate, cyclohexyl methacrylate, tetrahydrofurfuryl methacrylate, benzyl methacrylate, phenoxyethyl methacrylate, isobornyl methacrylate, dicyclopentenyl methacrylate, dicyclopentenyloxyethyl methacrylate, dicyclopentanyl methacrylate, 2-hydroxy Ethyl methacrylate, 4-hydroxybutyl methacrylate, 2-hydroxypropyl methacrylate, diethylaminoethyl methacrylate, diethylaminoethyl methacrylate, dimethylaminoethyl methacrylate quaternized product, methacrylic acid, 2-methacryloyloxyethyl succinic acid, 2-methacryloyloxyethyl hexa Hydrophthalic acid, 2- Methacryloyloxyethylphthalic acid, 2-methacryloyloxyethyl 2-hydroxyethylphthalic acid, neopentyl glycol methacrylic acid benzoate, 2-methacryloyloxyethyl-2-hydroxypropyl phthalate, glycidyl methacrylate, 2-methacryloyloxy Ethyl acid phosphate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, PEG # 200 dimethacrylate, PEG # 400 dimethacrylate, PEG # 600 dimethacrylate, 1,4-butanediol dimethacrylate, neopentylglycol di Methacrylate, 3-methyl-1,5-pentanediol dimethacrylate, 2-butyl-2-ethyl-1,3-propa Diol dimethacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol dimethacrylate, 1,10-decanediol dimethacrylate, glycerin dimethacrylate, 2-hydroxy-3-acryloyloxypropyl methacrylate, bisphenol A- EO adduct dimethacrylate, trifluoroethyl methacrylate, tetrafluoropentyl methacrylate, octafluoropentyl methacrylate, perfluorooctylethyl methacrylate, nonylphenol-EO adduct methacrylate, dimethylol tricyclodecane dimethacrylate, trimethylolpropane methacrylate benzoate , Hydroxypivalate neopentyl glycol dimethacrylate, tetrafurfuryl alcohol Methacrylate, ethyl carbitol oligomethacrylate, 1,4-butanediol oligomethacrylate, 1,6-hexanediol oligomethacrylate, trimethylolpropane oligomethacrylate, pentaerythritol oligomethacrylate, pentamethylpiperidylmethacrylate, tetramethylpiperidylmethacrylate, paracumylphenol -EO-modified methacrylate, N-methacryloyloxyethyl hexahydrophthalimide, isocyanuric acid-EO-modified dimethacrylate, 3-ethyl-3-hydroxymethyloxetane, 1,4-bis {[(3-ethyloxetane-3-yl) Methoxy] methyl} benzene, 3-ethyl-3-{[(3-ethyloxetane-3-yl) methoxy] methyl} oxetane, 3-ethyl -3- (2-ethylhexyloxymethyl) oxetane, 3-ethyl-3- (phenoxymethyl) oxetane, 3-ethyl-3- (cyclohexyloxy) methyloxetane, oxetanylsilsesquioxane, oxetanyl silicate, phenol novolac oxetane 1,3-bis [(3-ethyloxetane-3-yl) methoxy] benzene and the like, but is not limited thereto.

  Moreover, in a photocurable resin, it is preferable to contain the monomer which is an N-vinyl compound in 5 mass%-40 mass%. Here, examples of the monomer that is an N-vinyl compound that is particularly preferably used include at least one of N-vinylformamide, N-vinylacetamide, N-vinylpyrrolidone, and N-vinylcaprolamtam. By blending these N-vinyl compounds, the adhesion of the molded body to the base material can be improved, while the releasability from the mold after the photoreaction is good, which is preferable. The content of these monomers is preferably 5% by mass or more in order to exert the above effects, and when the content is 40% by mass or less, the degree of polymerization is low so as to bleed out from the molded product. It is preferable because by-products of the oligomer can be minimized and excessive moisture absorption of the molded body can be suppressed and the moisture resistance of the molded body is improved. The content of these monomers is more preferably in the range of 17% by mass to 35% by mass.

  Furthermore, in a photocurable resin, it is preferable to contain the silicone compound containing an acrylic group and / or a methacryl group in 0.1 mass%-10 mass%. Examples of the silicone compound include silicone acrylate compounds such as BYK-UV3500, BYK-UV3570 (manufactured by Big Chemie Japan), and ebecyl350 (manufactured by Daicel-Cytec) in which an acrylic group is bonded to a polydimethylsiloxane skeleton. It is done. By compounding these silicone compounds, it is possible to further improve the releasability of the molded product after the photoreaction from the mold, and these silicone compounds are also less likely to bleed out from the molded product. It is preferable for the purpose. The content of these silicone compounds is preferably 0.1% by mass or more in order to exhibit the above effects, and is preferably 10% by mass or less because the influence on the strength reduction of the molded product is small.

  The photocurable resin may contain a photopolymerization initiator. Examples of the photopolymerization initiator include 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2-methyl-1-phenyl-propane- 1-one, benzophenone, 1-hydroxy-cyclohexyl-phenyl-ketone, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy -1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] -phenyl} -2-methyl-propane, phenylglyoxylic acid methyl ester, 2-methyl-1- [4- (Methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4- Ruphorinophenyl) -butanone, 1,2-dimethylamino-2- (4-methyl-benzyl) -1- (4-morpholin-4-yl-phenyl) -butan-1-one, bis (2,4 , 6-Trimethylbenzoyl) -phenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis (η-5 2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrol-1-yl) -phenyl) titanium, 1,2-octanedione, 1- [4- (phenylthio ) -2- (O-benzoyloxime)] ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole- 3-yl] -1- (O-acetyloxime) and the like. Particularly in the present invention, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, 1,2-octanedione, 1- [4- (phenylthio) -2- (O -Benzoyloxime)] ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] -1- (O-acetyloxime) and the like are preferably used. These photopolymerization initiators can be applied alone, but can also be used in combination of two or more. In addition, it can also be applied in combination with known photopolymerization accelerators and sensitizers. The blending ratio of the photopolymerization initiator is preferably in the range of 0.1% to 5.0% by mass.

  Moreover, as a photocurable resin, the thing from which the foreign material (particle) was removed by techniques, such as filtration, is preferable. In the case of filtration, it is preferable to use a filter having a minimum particle size that can be captured of 1 μm or less, and more preferably 0.5 μm or less. For any minimum particle size, the filter capture efficiency is preferably 99.9% or more.

  In the laminate 1 according to the present embodiment, the base material 11 contains the thermoplastic resin described above, the fine structure layer 12 contains a photocurable resin, and the close contact between the base material 11 and the fine structure layer 12. The force is preferably larger than the relationship of the peeling force for peeling the protective film 13 from the fine structure layer 12. With this configuration, it is possible to roll-to-roll an antireflection film that is flexible and excellent in impact resistance. Moreover, when peeling off the protective film 13, the laminated body 1 can be manufactured without the fine structure layer 12 on the base material 11 being damaged and falling off. In addition, as a photocurable resin, the material which contains at least 1 or more types of monomer and photopolymerization initiator which contain two or more acrylic groups and / or methacryl groups in 1 molecule can be used. .

<Protective film>
In order to protect the fine structure from external stress and contamination, the protective film 13 is required to have appropriate flexibility, adhesiveness to the fine structure surface, shock absorption, and external stress dispersion characteristics. The thickness of the protective film 13 is not particularly limited as long as it satisfies these characteristics. However, if the protective film 13 is too thin, it is difficult to obtain necessary characteristics. Conversely, when it is thick, the protective function is improved. However, increasing the thickness is not preferable because the volume, weight, and cost increase. The suitable thickness of the protective film 13 is preferably 5 μm to 200 μm, more preferably 10 μm to 100 μm, and still more preferably 20 μm to 75 μm.

  When using the laminate 1, it is necessary to peel off the protective film 13. If the peeling force of the protective film 13 is 0.02 N / 25 mm or more and 4 N / 25 mm or less, it is easy to create a trigger for peeling and easy to handle. If the peeling force of the protective film 13 is 0.08 N / 25 mm or more and 2.5 N / 25 mm or less, it is more easy to handle and more preferable.

  In the laminate 1 according to the present embodiment, the thickness of the protective film 13 is 5 μm to 200 μm, and the peeling force for peeling the protective film 13 from the microstructure layer 12 is 0.02 N / 25 mm or more and 4 N / 25 mm or less. It is preferable that the peeling force for peeling the protective film 13 from the microstructure layer 12 is smaller than the breaking strength of the protective film 13. As a result, it is possible to ensure sufficient strength of the protective film 13 against the peeling force, so that the protective film 13 can be stably and cleanly protected without being damaged and remaining on the concavo-convex structure 12a at the time of peeling. The membrane 13 can be separated.

  The composition of the protective film 13 is not particularly limited as long as it can be peeled off at the interface with the fine structure layer 13, but preferably contains a water-insoluble resin material that is not affected by the environment, particularly humidity. The property of forming an emulsion that can be dissolved or dispersed in an organic solvent other than water is preferred. When the protective film 13 contains a water-insoluble resin material, it is excellent in storage stability without being affected by the storage environment, particularly humidity and rain. Specific examples of the resin material constituting the protective film 13 include nylon, polyvinyl acetate, ethylene vinyl acetate, fluorine, acrylic, polyurethane, polyurea, polyvinyl acetal, polyamide resin, styrene-ethylene-butylene-styrene, styrene- Heat of a copolymer containing a block structure such as butadiene-butylene-styrene, styrene-ethylene-propylene-styrene, styrene-butadiene-styrene, and styrene-isoprene-styrene, or a modified form of the copolymer. A plastic elastomer or the like can be used. The protective film 13 contains an antistatic agent, a pigment, dye, a leveling agent that stabilizes the film-forming property for improving visibility, an antioxidant, an ultraviolet absorber, and strength adjustment for improving the durability of the protective film. An additive such as an inorganic filler may be included.

  In the laminate 1 according to the present embodiment, the protective film 13 is made of water-insoluble nylon, ethylene vinyl acetate, fluorine, acrylic, polyurethane, polyurea, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide, and acrylic. It is preferable that at least one resin selected from the group consisting of Thereby, since the protective film 13 does not adhere firmly at the interface between the concavo-convex structure 12 a and the protective film 13, peeling is possible at the interface between the concavo-convex structure 12 a and the protective film 13. In the present specification, the main component of the protective film 13 means containing 50 mass% or more with respect to the total weight of the protective film 13.

  Moreover, in the laminated body 1 which concerns on this Embodiment, the protective film 13 is styrene-ethylene-butylene-styrene, styrene-butadiene-butylene-styrene, styrene-ethylene-propylene-styrene, styrene-butadiene-styrene, and It is preferable to include a copolymer containing at least one block structure selected from the group consisting of styrene-isoprene-styrene in the molecular chain, or a thermoplastic elastomer of a modified body of the copolymer. Thereby, since the protective film 13 does not adhere firmly at the interface between the concavo-convex structure 12 a and the protective film 13, peeling can be performed at the interface between the concavo-convex structure 12 a and the protective film 13.

  Moreover, in the laminated body 1 which concerns on this Embodiment, it is preferable that the protective film 13 is a polyurethane and / or urea resin using the aliphatic diisocyanate containing a urea bond, and C4 or more glycol. Thereby, the cohesive force of the protective film 13 increases, the adhesive force with the interface of the concavo-convex structure 12a decreases, and a suitable balance between adhesiveness and peelability can be realized.

<Method for forming protective film>
The protective film 13 is made into a solution and applied onto the concavo-convex structure 12 a of the fine structure layer 12. The solvent to be dissolved is not particularly limited as long as the microstructure layer 12 and the substrate 11 are not eroded. Specific examples include alcohol solvents such as methanol, ethanol, isopropyl alcohol, and butanol, and organic solvents such as acetone, methyl isobutyl ketone, methylene chloride, chloroform, cyclohexane, toluene, ethyl acetate, THF, and dimethylacetamide. May be used as a mixed solvent. Various kinds of solution viscosities are adjusted by the coating method. The coating method is not particularly limited, and roll coater method, (micro) gravure coater method, air doctor coater method, blade coater method, knife coater method, rod coater method, curtain (flow) coater method, kiss coater. Examples thereof include a method such as a method, a bead coater method, a cast coater method, a rotary screen method, a dip coating method, a slot orifice coater method, a bar code method, a spray coating method, a spin coating method, and an extrusion coater. Considering productivity, spray coating, die coating, and gravure coating that can be continuously produced are excellent. The solvent in the protective film 13 is removed by a dryer. It is desirable that the laminated body 1 having the protective film 13 thus produced does not curl. When the laminate 1 is curled, a problem occurs when an adhesive layer and a release film layer are formed later. The curl of the laminate 1 is cut out with a sample of 100 mm × 100 mm and placed on a smooth surface, and the float is preferably 20 mm or less, more preferably 10 mm or less, and further preferably 5 mm or less.

  In the laminate 1 according to the present embodiment, it is desirable that the peeling force for peeling the protective film 13 from the microstructure layer 12 is smaller than the breaking strength of the protective film 13. Further, it is desirable that the peeling force for peeling the protective film 13 from the fine structure layer 12 is smaller than the adhesion force between the base material 11 and the fine structure layer 12.

  Moreover, the back surface (the other main surface facing the main surface on which the fine structure layer 12 is formed) of the base material 11 can be formed by application of a ready-made adhesive sheet or an adhesive. The pressure-sensitive adhesive sheet can be laminated with an elastic roll or the like while venting air through a release film. When the coating is formed, a silicone-based or fluorine-based release film 15 is laminated and laminated by post-processing. Here, it is preferable in terms of optical characteristics that the refractive index of the pressure-sensitive adhesive to be used has a small difference from the refractive index of the substrate 11.

  As described above, in the laminated body 1 according to the above embodiment, the protective film 13 is provided on the fine structure layer 12 so as to be in contact with the concave and convex portions of the concavo-convex structure 12a. Since the protective film 13 is filled in the concave portion of the concavo-convex structure 12a, the contact area between the fine structure layer 12 and the protective film 13 increases. Thereby, even if it is a case where the protective film 13 with the adhesive force between the fine structure layers 12 is 0.01 N / cm or less, it becomes possible to adhere the protective film 13 and the fine structure layer 12. Therefore, it becomes possible to protect the concavo-convex structure 12a from the contamination of the fine structure and external stress, and it is possible to suppress the fine concavo-convex structure 12a from being damaged and the dusting contamination accompanying the damage. Moreover, since the uneven structure 12a of the fine structure layer 12 is covered with the protective film 13 having a low adhesive force with the fine structure layer 12, the protective film 13 can be easily peeled off, and the protective film 13 is peeled off. Breakage of the uneven structure 12a of the fine structure layer 12 and the protective film 13, and adhesive residue of the material constituting the protective film 13 can be suppressed, and a decrease in optical performance can be suppressed before and after the protective film 13 is peeled off. Further, a cleaning process for cleaning the fine structure layer from which the protective film 13 has been peeled is not necessary, and the reattachment of the protective film 13 after the peeling to the fine structure layer 12 can be suppressed, so that the handleability can be improved, and Space and cost can be reduced. In addition, a sufficient protective function is exhibited with a thin film as compared with the case where a conventional adhesive sheet is used as the protective film 13.

  Hereinafter, examples made to clarify the present invention will be described, but the present invention is not limited to these examples. First, the measurement method of the measured value in an Example is demonstrated.

<Measurement of protective film thickness>
It measured with the contact-type thickness meter (the Mitutoyo company make, Digimatic indicator ID-C112CX).

<Evaluation of curls>
The evaluation sample was cut out to 100 mm × 100 mm, and the maximum value floating from the smooth surface generated when the sample was placed on the smooth surface was measured with a ruler. The case where the float from the smooth surface was 10 mm or less was evaluated as ◯, and the case where the float from the smooth surface exceeded 10 mm was evaluated as x.

<Protection function 1: Pencil hardness test>
An evaluation sample was cut out to 80 mm × 30 mm, mounted on a pencil hardness tester (manufactured by Tester Sangyo Co., Ltd.), tested with pencil 3H, 250 g weight, moving speed 5 mm / second, and then the protective film was peeled off to form a fine structure. The presence or absence of body destruction was determined. The case where there was no damage of the fine structure layer was marked with ◯, and the case where the fine structure layer was broken was marked with x.

<Protective function 2: Steel wool test>
An evaluation sample was cut out to 80 mm × 40 mm and fixed to a sample evaluation stage of a surface property measuring machine (manufactured by Imoto Seisakusho). Next, steel wool (manufactured by Nippon Steel Wool Co., Ltd., product number No. 0000) was mounted on a 10 mm diameter flat plate surface, attached to a surface property measuring instrument, and brought into contact with the evaluation sample. The evaluation conditions were 30 reciprocations with a load of 1 kg and a moving speed of 5 mm / second. Then, the protective film was peeled off and the presence or absence of destruction of the fine structure was determined. The case where there was no damage of the fine structure layer was marked with ◯, and the case where the fine structure layer was broken was marked with x.

<Possibility of peelability of protective film>
The evaluation sample was cut out to 100 mm × 100 mm, and the end of the protective film was pinched to determine whether the protective film could be peeled off without breaking the protective film. The case where it peeled in the interface of a fine structure layer and a protective film was set as (circle), and it was set as x except the case where it peeled at the interface between a defective defect and a fine structure layer and a protective film.

<Measurement of peel strength of protective film>
The peel strength of the protective film was determined by cutting the evaluation sample into a strip with a width of 25 mm and a length of 100 mm, and then subjecting the sample to a 90 ° peel test jig based on JIS Z1528 in a room at 23 ° C. and 50% RH. Was used to measure the peeling force at a peeling speed of 300 mm / min with a tensile tester.

<Measurement of adhesive strength of protective film>
The adhesive force between the protective film after peeling and the fine structure layer is as follows: the protective film peeled off in an environment of 23 ° C. and 50% RH is cut into 10 mm × 100 mm strips and peeled off onto the fine structure Put them so that they face each other. Next, the sample is pressed with a rubber roller (for example, soft urethane roller product number No. 10840 manufactured by Ota Seisakusho Co., Ltd. can be used) with a load that does not destroy the shape of the fine structure. The peeling force of this sample was measured at a peeling speed of 300 mm / min with a tensile tester using an adhesive tape 90 degree peel test jig based on JIS Z1528 in a room at 23 ° C. and 50% RH. However, in the case where the protective film does not adhere to the fine structure layer and easily deviates, it was set to less than 0.01 N / cm without measuring the adhesive force with a tensile tester.

<Measurement of reflectance before and after peeling>
The reflectance before and after peeling was measured with a reflection spectral film thickness meter (manufactured by Otsuka Electronics Co., Ltd., FE3000: automatic stage specification). The measurement conditions are absolute reflectance measurement, the measurement mode is mapping, the objective lens is multiplied by 25 times, the baseline is adjusted with reference to aluminum, and the reflectance of BK7 with known reflectance is also measured as another reference. The sample was measured after confirming that the device was normal. Note that the mapping was set so that the reflected light was measured at approximately equal intervals in the 40 mm × 40 mm range with four X-axis locations and four Y-axis locations for a total of 16 locations. The case where the change in reflectance before and after peeling was 0.1% or less was marked as ◯, and the case where the change in reflectance was greater than 0.1% was marked as x.

<Composition of fine structure layer>
Next, three types of photocurable resin compositions of the microstructure layer used in the examples will be described. In this example, the following three photocurable resin compositions were used as the fine structure layer.

<A composition of photocurable resin>
In a brown container, add urethane acrylate (Beamset 575CB, Arakawa Chemical Co., Ltd.) 140g, N-vinylpyrrolidone 40g, silicone diacrylate (EBECRYL350, Daicel Cytec Co., Ltd.) 16g in this order, and in a 50 ° C hot water bath. The viscosity of the resin was lowered by warming for about 15 minutes. With the resin viscosity lowered, the resin was stirred vigorously with a spatula and mixed until uniform. After cooling to room temperature, 4 g of the initiator DAROCUR TPO (Ciba) was added, and the initiator was dissolved with an ultrasonic device for about 2 hours. This was designated as Resin A.

<B composition of photocurable resin>
In a 500 mL brown bottle, 150 g of urethane acrylate (UV3000B, manufactured by Nippon Synthetic Chemical Industry), 150 g of polyethylene glycol diacrylate (KAYARAD, PEG400DA, manufactured by Nippon Kayaku Co., Ltd.), 1,9-nonanediol diacrylate (light acrylate 1.9ND) -A, manufactured by Kyoeisha Chemical Co., Ltd.) 150 g, N-vinylpyrrolidone 23.2 g, silicone diacrylate (EBECRYL350, manufactured by Daicel Cytec Co., Ltd.) in the order of 800 mg, and in a light bath at 50 ° C. for about 15 minutes. The viscosity of the resin was lowered by warming. With the resin viscosity lowered, the resin was stirred vigorously with a spatula and mixed until uniform. After cooling to room temperature, 9.1 g of the initiator DAROCUR TPO (Ciba) was added, and the initiator was dissolved with an ultrasonic device for about 2 hours. This was designated as Resin B.

<C composition of photocurable resin>
In a brown container, 165 g of trimethylolpropane triacrylate (Aronix M309, manufactured by Toagosei Co., Ltd.), 165 g of 1,9-nonanediol diacrylate (light acrylate 1.9ND-A, manufactured by Kyoeisha Chemical Co., Ltd.), N-vinylpyrrolidone 165 g, 2.5 g of silicone diacrylate (EBECRYL350, manufactured by Daicel Cytec) and 10 g of DAROCUR TPO (manufactured by Ciba) were added in this order, and the mixture was uniformly dissolved with an ultrasonic device for about 2 hours under light shielding. This was designated as Resin C.

<Base material>
As a base material, (a) it is transparent in a wavelength region according to the purpose of use, (b) good adhesiveness with a photocurable resin, (c) a refractive index difference with the photocurable resin is small, (d) The haze is required to be small. In the present example, a triacetyl cellulose film (hereinafter referred to as a TAC film, manufactured by Fuji Film, Fujitac (registered trademark)) that satisfies the above conditions was used as a base material.

<Example 1>
A nickel stamper A 0.2 mm thick flat plate stamper in which convex and concave elliptical pyramid structures with a pitch of 240 nm and a height of 300 nm patterned by a laser interference exposure method are arranged in a three-way lattice was processed into 300 mm and 200 mm rectangles. This nickel stamper was joined to a roll surface to obtain a stamper roll having a fine structure layer in which an uneven elliptical cone structure was formed. This stamper roll was subjected to a mold release process by a process manufactured by Durasurf HD-2101Z Daikin Kasei.

Next, the photocurable resin (A composition) was continuously applied to a roll of TAC film (film length 250 m) having a thickness of 80 μm and a width of 250 mm by a gravure coater with a width of 200 mm and a thickness of 0.8 μm. Next, the coated surface is brought into contact with the surface of the roll stamper on which the uneven elliptical cone structure is formed, and from the TAC film side with a metal halide lamp (made by USHIO INC., Model number UVC-2519-1MNSC7-MS01) with a light amount of 1 J / cm ² . Photocured. Next, the TAC film in which the fine structure was continuously transferred to the photocurable resin A was peeled off from the roll stamper and wound into a roll shape. Next, the TAC film on which the fine structure layer is formed is cut out by 200 mm × 200 mm, and a urethane resin (manufactured by DIC, product name: Crisbon ASPU-121) is used as a protective film on the fine structure layer to form a solid content concentration with isopropyl alcohol. It adjusted to 20 weight% and apply | coated with the knife coater. Next, this TAC film was allowed to stand for 30 minutes in a draft of 23 ° C. and 50% RH, and further dried in an oven at 80 ° C. for 30 minutes to remove the solvent, thereby producing a laminate. The evaluation results of the evaluation samples are shown in Table 1 below. In Table 1 below, the pattern (b) of the fine structure layer is a three-sided arrangement of uneven elliptical cones having a pitch of 240 nm and a height of 300 nm, and the pattern (b) is a pattern having a pitch of 300 nm and a height of 320 nm. An uneven elliptical cone is arranged in three directions.

  In FIG. 5, the scanning electron microscope (SEM: Scanning Electron Microscope) photograph of the sample for evaluation is shown. As can be seen from FIG. 5, in the laminate of Example 1, it can be seen that the protective film is continuously in contact with the concave and convex portions of the concavo-convex structure of the microstructure layer.

  FIG. 6 shows the reflectance change before and after the formation of the protective film of the laminate of Example 1. In FIG. 6, 16 spectra obtained by measuring reflected light at a total of 16 locations at 4 locations on the X axis and 4 locations on the Y axis are overwritten in the 40 mm × 40 mm range of the laminate. As shown in FIG. 6, it can be seen that the light reflectance after the protective film formation (see FIG. 6B) shows substantially the same reflectance as the light reflectance before the protective film formation (see FIG. 6A). From this result, in the laminated body of Example 1, it turns out that the fall of optical performance is small before and after formation of a protective film.

<Example 2>
A laminate was fabricated under the same conditions as in Example 1 except that the pitch of the uneven elliptical cone structure of the nickel stamper used in Example 1 was 300 nm and the height was 320 nm. The evaluation results of the evaluation samples are shown in Table 1 below.

<Example 3>
A laminate was produced under the same conditions as in Example 1 except that the photocurable resin used in Example 1 had a B composition. The evaluation results of the evaluation samples are shown in Table 1 below.

<Example 4>
A laminate was produced under the same conditions as in Example 1 except that the photocurable resin used in Example 1 had a C composition. The evaluation results of the evaluation samples are shown in Table 1 below.

<Example 5>
A laminate was produced under the same conditions as in Example 1 except that the type of protective film used in Example 1 was urethane resin (product name: Crisbon ASPU-112, manufactured by DIC Corporation). The evaluation results of the evaluation samples are shown in Table 1 below.

<Example 6>
A laminate was produced under the same conditions as in Example 1 except that the type of the protective film used in Example 1 was urethane resin (product name: Crisbon ASPU-116, manufactured by DIC Corporation). The evaluation results of the evaluation samples are shown in Table 1 below.

<Example 7>
The type of protective film used in Example 1 was an alcohol-soluble nylon resin (product name: Amilan CM8000 manufactured by Toray Industries, Inc.), the alcohol-soluble nylon resin was adjusted to a solid content concentration of 15% by weight with methyl alcohol, and applied with a knife coater. A laminate was produced under the same conditions as in Example 1 except for the above. The evaluation results of the evaluation samples are shown in Table 1 below.

<Comparative Example 1>
A laminate was produced under the same conditions as in Example 1 except that no protective film was formed on the microstructure layer. The evaluation results of the evaluation samples are shown in Table 1 below.

<Comparative example 2>
The type of the protective film used in Example 2 was a water-soluble polyurethane resin (manufactured by DIC, product name Bondic 1310NE), and the water-soluble polyurethane resin was applied without being diluted with a knife coater. Next, the TAC film was left in a 23 ° C., 50% RH draft for 24 hours, and further dried in an oven at 80 ° C. for 30 minutes to remove the solvent. Regarding other conditions, a laminate was produced under the same conditions as in Example 2. The evaluation results of the evaluation samples are shown in Table 1 below.

<Comparative Example 3>
The type of the protective film used in Example 2 was a water-soluble polyurethane resin (manufactured by DIC, product name: Hydran AP-201), and was applied with a knife coater without diluting the water-soluble polyurethane resin. Next, the TAC film was left in a 23 ° C., 50% RH draft for 24 hours, and further dried in an oven at 80 ° C. for 30 minutes to remove the solvent. Regarding other conditions, a laminate was produced under the same conditions as in Example 2. The evaluation results of the evaluation samples are shown in Table 1 below.

  As can be seen from Table 1, a protective film having an adhesive force of 0.01 N / cm or less (peeling force of 0.02 N / 25 mm to 4 N / 25 mm or less) after peeling from the microstructure layer was used. In this case, the protective function is good, and it can be seen that good results are obtained in both the pencil hardness test and the steel wool test (Examples 1 to 7). When an alcohol-soluble nylon resin is used, curling may occur even if the protective function is sufficient, and handling may be slightly worse (Example 7). On the other hand, when the protective film is not provided, the protective function cannot be obtained (see Comparative Example 1). Moreover, even when a protective film is provided, when a water-soluble urethane resin is used, the optical performance of the laminate is greatly reduced before and after the protective film is peeled off (Comparative Example 2) or the peeling itself cannot be performed. (Comparative Example 3).

  INDUSTRIAL APPLICABILITY The present invention has an effect that it can suppress damage to the concavo-convex structure of the fine structure layer and dust generation contamination accompanying the damage, and can suppress a decrease in optical performance before and after peeling of the protective film. Further, it is possible to suitably use a molded lens body such as a sheet or an optical element. In addition, it is possible to prevent contamination, damage, and destruction during construction, transportation, and storage of the laminate.

DESCRIPTION OF SYMBOLS 1 Laminate 11 Base material 12 Fine structure layer 13 Protective film 14 Adhesive layer 15 Release film

Claims (8)

A fine structure layer having a concavo-convex structure formed on a surface thereof, and a protective film provided on the fine structure layer and contacting the concave and convex portions to cover the concavo-convex structure,
In the fine structure layer, a pitch between adjacent convex portions is equal to or less than a wavelength of visible light, the protective film includes a water-insoluble resin material, and the fine structure layer is separated from the fine structure layer. A laminate having an adhesive strength of 0.01 N / cm or less.   The protective film has a thickness of 5 μm to 200 μm, a peeling force for peeling the protective film from the fine structure layer is 0.02 N / 25 mm or more and 4 N / 25 mm or less, and the fine structure layer to the protective film The laminate according to claim 1, wherein a peeling force for peeling the film is smaller than a breaking strength of the protective film.   The protective film comprises at least one resin selected from the group consisting of water-insoluble nylon, ethylene vinyl acetate, fluorine, acrylic, polyurethane, polyurea, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide, and acrylic. The laminate according to claim 1, wherein the laminate is contained as a main component.   The protective film is at least one selected from the group consisting of styrene-ethylene-butylene-styrene, styrene-butadiene-butylene-styrene, styrene-ethylene-propylene-styrene, styrene-butadiene-styrene, and styrene-isoprene-styrene. The laminate according to claim 1 or 2, comprising a copolymer containing one block structure in a molecular chain, or a thermoplastic elastomer of a modified body of the copolymer.   The laminate according to claim 1 or 2, wherein the protective film includes a polyurethane and / or a urea resin using an aliphatic diisocyanate containing a urea bond and a glycol having 4 or more carbon atoms. Further comprising a base material provided on the microstructure layer and containing a thermoplastic resin;
The microstructure layer contains a photocurable resin,
The laminate according to any one of claims 1 to 5, wherein an adhesion force between the base material and the microstructure layer is larger than a relationship of a peeling force for peeling the protective film from the microstructure layer. .   The laminate according to claim 6, comprising an adhesive layer provided on the base material without the fine structure layer, and a release film provided on the adhesive layer.   The said base material has a pair of main surface, and the said microstructure layer and the said protective film were laminated | stacked in this order on the said both main surfaces of a pair, respectively. Laminated body.