JP6424550B2 - Antireflective articles and art objects - Google Patents

Description

  The present invention relates to an antireflective article and an art display.

  In recent years, with regard to an anti-reflection film which is a film-shaped anti-reflection article, there has been proposed a method for achieving anti-reflection by closely arranging a large number of minute projections on the surface of a transparent substrate (transparent film) (for example, Patent documents 1 to 3). This method utilizes the principle of a so-called moth eye structure, in which the refractive index for incident light is continuously changed in the thickness direction of the substrate, thereby making the discontinuous interface of the refractive index To eliminate reflection and to prevent reflection.

  Such a moth-eye structure as a number one antireflective article is generally produced by a nanoimprint process by a photo-curing reaction using a mold having nano-level fine holes which are produced by repeating anodic oxidation and etching of aluminum. (E.g., Patent Document 4).

  Various uses have been proposed for such an antireflective article, and for example, it is disposed on the surface of a display case for protecting an information display unit of various image display devices or exhibits such as works of art, goods, etc. It has been proposed to improve the visibility by reducing the reflection of external light such as a lamp.

However, an antireflective article having such a moth-eye structure is a material used for decomposition of a resin or a photopolymerization initiator during a photocuring reaction when producing an antireflective article, and a transparent base material such as a triacetyl cellulose film. Outgassing caused by the problem is a problem. When the antireflective article is used in a showcase or the like of a display, generation of outgassing containing a component such as an aldehyde or an organic acid is particularly problematic since there is a concern that the deterioration of the display, deterioration of the display, etc. may be promoted.
In conventional antireflective articles, in order to prevent problems due to outgassing, for example, the antireflective articles are allowed to stand for a certain period of time in a clean air environment, for example, for several months to release outgassing, and then to We use prevention article.

Japanese Patent Application Laid-Open No. 50-70040 Japanese Patent Publication No. 2003-531962 Patent No. 4632589 WO 2010/087139 pamphlet

  However, when the antireflective article is subjected to so-called drying, there is a problem that the antireflective article can not be used immediately after preparation. Further, as can be seen from the evaluation results of Comparative Example 2 described later, it is difficult to sufficiently suppress the generation of outgassing even if the antireflective article is withered.

  The present invention has been made in view of the above problems, and it is possible to suppress the generation of outgassing, to suppress the influence of the outgassing on an antireflective article having excellent antireflectivity, and to an art object by the outgassing, and to exhibit art with excellent visibility. Intended to provide the body.

The antireflective article according to the present invention has on its surface a fine uneven shape provided with a microprojection group in which a plurality of microprotrusions are closely arranged on at least one surface of a transparent substrate, and the resin composition An antireflective article comprising a fine uneven layer made of a cured product, comprising:
The transparent substrate contains a polyester resin,
The microprotrusions have a shortest wavelength in a wavelength band of light for reflection prevention as Λ _min and an average value of the spacing d between adjacent projections of the microprotrusions as d _AVG .
d _AVG Λ _min
Have the relationship
The resin composition is an ionizing radiation curable resin composition containing at least one selected from the group consisting of (meth) acrylate ionizing radiation curable resins, and ethylene oxide modified bisphenol A diacrylate and ethylene oxide modified trimethylol Based on the total solids contained in the resin composition, a compound having a total of 60 to 90% by mass based on the total solids contained in the resin composition and having at least one propane triacrylate and having a carbodiimide group To 0.1% to 5.0% by mass , further containing at least one of tridecyl acrylate and dodecyl acrylate, and containing no monofunctional (meth) acrylate other than tridecyl acrylate and dodecyl acrylate I assume.

In the antireflective article according to the present invention, the total content ratio of the tridecyl acrylate and the dodecyl acrylate is 5 with respect to a total of 100 parts by mass of the ethylene oxide modified bisphenol A diacrylate and the ethylene oxide modified trimethylolpropane triacrylate. It is preferable that it is -20 mass parts.

  The art exhibit according to the present invention includes the antireflective article according to the present invention and an art, and the antireflective article is arranged such that the surface having the fine concavo-convex shape faces the side of the art It is characterized by

  ADVANTAGE OF THE INVENTION According to this invention, generation | occurrence | production of outgas is suppressed, the influence on the artwork by the antireflective article which is excellent in antireflection property, and outgas is suppressed, and the art exhibit body excellent in visibility can be provided.

It is a sectional view showing typically an example of the antireflection article concerning the present invention. It is sectional drawing (FIG. 2 (a)), a perspective view (FIG. 2 (b)), and a top view (FIG. 2 (c)) which are provided to description of the multimodal microprotrusion which has multiple vertices. It is a perspective view (FIG. 3 (a)) and a top view (FIG. 3 (b)) of the convex-projections group comprised by several micro protrusion. It is a schematic cross section which shows an example of a fine concavo-convex layer. It is the schematic which shows an example of the manufacturing method of the reflection preventing article concerning this invention. It is a sectional view showing typically an example of the art exhibition object concerning the present invention. It is a sectional view showing typically another example of the art exhibition object concerning the present invention. It is an enlarged photograph which shows an example of the fine concavo-convex layer of the antireflection article concerning the present invention which was used for explanation of the fine concavo-convex field which has irregularly arranged microprotrusion determined by atomic force microscope. It is a figure which shows the local maximum of microprotrusion in the example of the micro uneven | corrugated layer of FIG. It is a figure which shows the Delaunay figure in the example of the fine concavo-convex layer of FIG. It is a histogram of frequency distribution of distance between adjacent maximum points created from the Delaunay diagram of FIG. It is a histogram of frequency distribution of micro protrusion height in the example of the fine concavo-convex layer of FIG. It is a schematic histogram of the frequency distribution of microprotrusion heights, which serves as an explanation for low elevation area, middle elevation area, and high elevation area regarding microprojection height. It is a flowchart which shows an example of the manufacturing process of a metal mold | die. It is a schematic diagram which shows the formation process of the fine hole formed of the manufacturing process of the metal mold | die of FIG. FIG. 15 is a schematic view for explaining a process of forming micro holes of different depths in the manufacturing process of the mold of FIG. 14; It is the schematic of the sampling method in outgassing concentration analysis by a small chamber method. It is a histogram which shows an example of frequency distribution of micro protrusion height H of the reflection preventing article concerning the present invention. It is a histogram which shows another example of frequency distribution of microprotrusion height H of the reflection preventing article concerning the present invention. It is a planar view enlarged photograph which shows an example of a multimodal microprotrusion. It is a perspective view which shows an example of the shape of a microprotrusion. 22 is a plan view, a front view, and a side view of the microprotrusion shown in the example of FIG. 21. FIG. It is a perspective view which shows an example of the shape of a microprotrusion different from the microprotrusion of FIG. FIG. 24 is a plan view, front view, and side view of the microprotrusion shown in the example of FIG. 23; It is a perspective view which shows an example of the shape of a microprotrusion different from the microprotrusion of FIG.21 and FIG.23. FIG. 26 is a front view and a side view of the microprotrusion shown in the example of FIG. 25.

Hereinafter, the antireflective article and the art exhibit according to the present invention will be described in detail in order.
In the present specification, the term "article" is a concept including aspects such as "plate", "sheet", and "film".
Furthermore, as used herein, the terms such as “parallel”, “orthogonal”, “identical”, values of length and angle, etc., which specify the shape and geometrical conditions and their degree, etc. Without being bound by the meaning, it shall be interpreted including the extent to which the same function can be expected.
In the present invention, (meth) acrylic represents each of acrylic or methacrylic, (meth) acrylate represents each of acrylate or methacrylate, and (meth) acryloyl represents each of acryloyl or methacryloyl.
Moreover, the hardened | cured material of a resin composition in this invention means what was solidified through reaction without passing through.

[Anti-reflection article]
The antireflective article according to the present invention has on its surface a fine uneven shape provided with a microprojection group in which a plurality of microprotrusions are closely arranged on at least one surface of a transparent substrate, and the resin composition An antireflective article comprising a fine uneven layer made of a cured product, comprising:
The microprotrusions have a shortest wavelength in a wavelength band of light for reflection prevention as Λ _min and an average value of the spacing d between adjacent projections of the microprotrusions as d _AVG .
d _AVG Λ _min
Have the relationship
The said resin composition is characterized by containing the compound which has a carbodiimide group 0.1-5.0 mass% with respect to the total solid contained in the said resin composition.

The antireflective article according to the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing an example of the antireflective article according to the present invention. The antireflective article 10 illustrated in FIG. 1 has a fine uneven layer 2 having a fine uneven shape on one surface side of the transparent substrate 1.
Wherein the surface of the fine uneven layer 2 is a fine uneven surface 2a having a fine projection group fine projections 3 will be set, the microprojections 3, the shortest wavelength in the wavelength band of light to improve the anti-reflection lambda _min , an average value of the adjacent projections spacing of the microprotrusions 3 d (FIG. 1) is taken as _{d AVG,} by having a _{d AVG} ≦ Λ _min the relationship, achieving antireflection of light having a wavelength greater than or equal to lambda _min be able to.

In the antireflective article according to the present invention, the generation of outgassing is suppressed by the resin composition used for the fine uneven layer containing a specific amount of a compound having a carbodiimide group.
This is because the compound having a carbodiimide group reacts with an organic acid that can serve as an outgas to be dehydrated and condensed, thereby suppressing the generation of the organic acid as an outgas and suppressing the generation of the organic acid, thereby achieving an equilibrium reaction. It is presumed that the oxidation of aldehydes proceeds from this, and the generation of aldehydes as outgas is also suppressed.

<Fine unevenness layer>
The micro-relief layer included in the antireflective article according to the present invention has a micro-relief shape provided with a micro-projection group in which a plurality of micro-protrusions are closely arranged, and is made of a cured product of a resin composition.

[Resin composition]
The resin composition for the fine asperity layer contains at least a resin and a compound having a carbodiimide group, and optionally contains other components such as a polymerization initiator. Here, in the present invention, a compound having a carbodiimide group represents a generic term for compounds containing a carbodiimide group, a monocarbodiimide compound containing only one carbodiimide group in one molecule, and two or more carbodiimide groups in one molecule. Containing polycarbodiimide compounds.
In the present invention, since the resin composition for the fine asperity layer contains a compound having a carbodiimide group, the cured product of the resin composition forming the fine asperity layer has a compound having a carbodiimide group, At least one of the components derived from the compound having a carbodiimide group (for example, a reaction product or a decomposition product with an organic acid) is included.

  Examples of the monocarbodiimide compound include N, N′-di-o-toluylcarbodiimide, N, N′-diphenylcarbodiimide, N, N′-di-2,6-dimethylphenylcarbodiimide, N, N′-bis (2,6-diisopropylphenyl) carbodiimide, N, N'-dioctyldecylcarbodiimide, N-triyl-N'-cyclohexylcarbodiimide, N, N'-di-2,2-di-t-butylphenylcarbodiimide, N- Triyl-N'-phenylcarbodiimide, N, N'-di-p-nitrophenylcarbodiimide, N, N'-di-p-aminophenylcarbodiimide, N, N'-di-p-hydroxyphenylcarbodiimide, N, N '-Dicyclohexylcarbodiimide, N, N'-di-p-toluyl carbodiimide 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide, 1- [3- (dimethylamino) propyl] -3-ethyl carbodiimide, N, N'-diisopropyl carbodiimide, N-cyclohexyl-N '(2- Examples include morpholinoethyl) -carbodiimide, dimethyl carbodiimide, diisobutyl carbodiimide, dioctyl carbodiimide, t-butyl isopropyl carbodiimide, di-t-butyl carbodiimide, di-β-naphthyl carbodiimide and the like.

As the polycarbodiimide compound, those produced by a conventionally known method can be used, and there is no particular limitation. For example, the polycarbodiimide compound can be synthesized by decarbon dioxide condensation reaction of a diisocyanate compound.
Examples of the diisocyanate compound include aromatic, aliphatic and alicyclic diisocyanates. Specific examples thereof include tolylene diisocyanate, xylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, cyclohexane diisocyanate and isophorone. Diisocyanate and dicyclohexyl diisocyanate can be mentioned, and more specifically, for example, diisocyanate compounds described in JP-B-47-33279 and JP-A-9-235508 can be mentioned.
Moreover, as a method for producing the polycarbodiimide compound, for example, methods described in JP-B-47-33279 and JP-A-9-235508 can be used.

Moreover, a commercial item can also be used as a compound which has the said carbodiimide group.
As a commercial item of the said monocarbodiimide compound, Wako Pure Chemical Industries Ltd. various carbodiimide type condensing agent etc. can be mentioned, for example.
As a commercial item of the polycarbodiimide compound, for example, Carbodilite series manufactured by Nisshinbo Chemical Co., Ltd. can be mentioned.

  In the present invention, among them, a polycarbodiimide compound is preferably used as the compound containing a carbodiimide group, from the viewpoint that bleeding out is suppressed and the storage stability of the antireflective article is excellent.

The content of the compound having a carbodiimide group is 0.1 with respect to the total solid content contained in the resin composition, from the viewpoint of being able to form a fine uneven layer having excellent antireflective properties while suppressing the generation of outgassing. It is -5.0 mass%. In addition, the content of the compound having a carbodiimide group is preferably 0.5% by mass or more from the viewpoint of further suppressing the generation of outgassing, excellent in the formability of the fine uneven layer, and excellent in long-term storage stability It is preferable that it is 3.0 mass% or less from a point.
In addition, in this invention, solid content represents all the components except a solvent.

  The compound having a carbodiimide group preferably has an isocyanate group content of 10% by mass or less, preferably 5% by mass or less, in the total amount of the compounds having a carbodiimide group. It is preferable from the point of view.

  The resin contained in the resin composition for the fine asperity layer used in the present invention is not particularly limited, and examples thereof include ionizing radiation curable resins such as (meth) acrylates, epoxys and polyesters, and (meth) acrylates. Of various materials such as thermosetting resin such as urethane resin, urethane resin, epoxy resin and polysiloxane resin, thermoplastic resin such as (meth) acrylate resin, polyester resin, polycarbonate resin, polyethylene resin and polypropylene resin, and various curing forms Mold resin etc. are mentioned. In addition, ionizing radiation means electromagnetic waves or charged particles having energy capable of polymerizing and curing molecules, for example, all ultraviolet rays (UV-A, UV-B, UV-C), visible light, gamma rays , X-rays, electron beams and the like.

Among the above resins, ionizing radiation curable resins are preferably used in view of their excellent formability of fine concavo-convex shape and mechanical strength. The ionizing radiation curable resin is a mixture of a monomer having a radical polymerizable property and / or a cationic polymerizable bond in the molecule, a polymer having a low polymerization degree, and a reactive polymer, and the polymerization initiator It is to be cured. In addition, you may contain a non-reactive polymer.
The resin preferably contains at least one selected from the group consisting of (meth) acrylate ionizing radiation curable resins.
Hereinafter, the ionizing radiation curable resin composition containing at least one selected from the group consisting of (meth) acrylate ionizing radiation curable resins which are particularly preferably used will be specifically described by way of example.

(1) (Meth) Acrylate Even if it is a monofunctional (meth) acrylate having one (meth) acryloyl group in one molecule, two or more (meth) acryloyl groups in one molecule It may be a multifunctional (meth) acrylate which has, or may be a combination of a monofunctional (meth) acrylate and a multifunctional (meth) acrylate.
Among them, it is preferable to use a monofunctional (meth) acrylate and a multifunctional (meth) acrylate in combination, from the viewpoint that the microprotrusion achieves both flexibility and elastic recovery.

  Specific examples of monofunctional (meth) acrylates include, for example, methyl (meth) acrylate, hexyl (meth) acrylate, decyl (meth) acrylate, allyl (meth) acrylate, benzyl (meth) acrylate, butoxyethyl (meth) acrylate , Butoxy ethylene glycol (meth) acrylate, cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, glycerol (meth) acrylate, glycidyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate ) Acrylate, 2-hydroxypropyl (meth) acrylate, isobonyl (meth) acrylate, isodexyl (meth) acrylate, isooctyl (meth) acrylate, lauryl (meth) a Lilate, 2-methoxyethyl (meth) acrylate, methoxyethylene glycol (meth) acrylate, phenoxyethyl (meth) acrylate, stearyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, biphenyloxyethyl acrylate, bisphenol A diglycidyl (meth) acrylate, biphenyl yloxy ethyl (meth) acrylate, ethylene oxide modified (EO modified) biphenyl yloxy ethyl (meth) acrylate, bisphenol A epoxy (meth) acrylate etc. are mentioned. Among them, a monofunctional (meth) acrylate having a long-chain alkyl group having 10 or more carbon atoms is preferable from the viewpoint that the antifouling property of the surface of the cured product is improved and the fine projections are excellent in flexibility. It is even more preferable to include at least one of tridecyl (meth) acrylate and dodecyl (meth) acrylate. These monofunctional (meth) acrylic acid esters can be used alone or in combination of two or more.

  When monofunctional (meth) acrylate is used, the content of monofunctional (meth) acrylate is preferably 5 to 40% by mass with respect to the total solid content of the ionizing radiation curable resin composition, and 10 to 30 More preferably, it is mass%.

  Moreover, as specific examples of the polyfunctional (meth) acrylate, for example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, propylene di (meth) acrylate, hexanediol di (meth) acrylate, polyethylene glycol di ( (Meth) acrylate, bisphenol A di (meth) acrylate, tetrabromobisphenol A di (meth) acrylate, bisphenol S di (meth) acrylate, butanediol di (meth) acrylate, phthalic acid di (meth) acrylate, ethylene oxide modified ( EO modified) bisphenol A di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) Acrylate, tris (acryloxyethyl) isocyanurate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, urethane tri (meth) acrylate, ester tri (meth) acrylate, urethane hexa (meth) acrylate, ethylene Oxide-modified (EO-modified) trimethylolpropane tri (meth) acrylate and the like can be mentioned. Among them, it is preferable to use a multifunctional (meth) acrylate containing an alkylene oxide, and more preferable to use an ethylene oxide-modified polyfunctional (meth) acrylate, from the viewpoint that the microprotrusions are excellent in flexibility and recovery. It is even more preferable to include at least one of bisphenol A di (meth) acrylate, ethylene oxide modified trimethylolpropane tri (meth) acrylate, and polyethylene glycol di (meth) acrylate. Moreover, as said polyfunctional (meth) acrylate, what has an aromatic ring is preferable from the point by which generation | occurrence | production of outgas is reduced, and, specifically, ethylene oxide modified | denatured bisphenol A di (meth) acrylate is used preferably. Be

  The content of the polyfunctional (meth) acrylate is preferably 10 to 90% by mass, and more preferably 15 to 85% by mass, with respect to the total solid content of the ionizing radiation curable resin composition.

  The ionizing radiation curable resin composition preferably used in the present invention is a composition containing a multifunctional (meth) acrylate containing an alkylene oxide. Among them, the content of the polyfunctional (meth) acrylate containing the alkylene oxide is preferably 60 to 90% by mass, preferably 70 to 85% by mass, with respect to the total solid content of the ionizing radiation curable resin composition. It is more preferable that In addition, the content of the polyfunctional (meth) acrylate containing the alkylene oxide is preferably 80 to 98% by mass in the total (meth) acrylate compound to be used, and more preferably 85 to 95% by mass. preferable.

  In addition, the ionizing radiation curable resin composition of the present invention has at least a carbon number, from the viewpoint that microprotrusions of a cured product are easily compatible with flexibility and elastic recovery, and excellent wipeability and stain resistance are obtained. It is preferable to contain a (meth) acrylate having 10 or more long chain alkyl groups and a polyfunctional (meth) acrylate containing an alkylene oxide. Among them, the content ratio of (meth) acrylate having a long-chain alkyl group having 10 or more carbon atoms is preferably 5 to 20 parts by mass with respect to 100 parts by mass of polyfunctional (meth) acrylate containing alkylene oxide, More preferably, it is 10 to 15 parts by mass.

(2) Photopolymerization Initiator In order to initiate or accelerate the curing reaction of the (meth) acrylate, a photopolymerization initiator may be appropriately selected and used as necessary. Specific examples of the photopolymerization initiator include, for example, bisacyl phosphinxide, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2,2-dimethoxy-1 , 2-Diphenylethan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 2-methyl-1- [4-] (Methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, 2-hydroxy-2-methyl-1-phenyl -Propane-1-ketone, 2,4,6-trimethyl benzoyl diphenyl phosphine oxide, phenyl bis (2,4,6- trimethyl ben Benzoyl) - phosphine oxide, phenyl (2,4,6-trimethylbenzoyl) ethyl phosphinic acid and the like. These can be used alone or in combination of two or more.

  When using a photoinitiator, the content of the said photoinitiator is 0.8 to 20 mass% normally with respect to the total solid of an ionizing radiation curable resin composition, and 0.9 to 10 mass. % Is preferred.

(3) Antistatic Agent In the present invention, the resin composition preferably contains an antistatic agent. By containing the antistatic agent, it is possible to suppress the adhesion of stains on the surface of the fine uneven layer, and the stains are easily removed at the time of wiping.
The antistatic agent can be appropriately selected and used from conventionally known ones. Specific examples of the antistatic agent include, for example, quaternary ammonium salts, pyridinium salts, various cationic compounds having cationic groups such as primary to tertiary amino groups, sulfonic acid bases, sulfuric acid ester bases, phosphoric acid esters Base, anionic compound having an anionic group such as phosphonate group, amphoteric compound such as amino acid type, amino sulfate ester type, nonionic compound such as amino alcohol type, glycerin type, polyethylene glycol type etc, alkoxide of tin and titanium And such organic metal compounds and metal chelate compounds such as their acetylacetonate salts. Among them, cationic compounds are preferable, cationic compounds having a tertiary amino group are more preferable, and trialkylamines such as N, N-dioctyl-1-octaneamine are even more preferable.

  When an antistatic agent is used, the content of the antistatic agent is usually 1 to 20% by mass, preferably 2 to 10% by mass, based on the total solid content of the ionizing radiation curable resin composition. . In the present invention, solid content refers to all components excluding the solvent.

(4) Solvent In the present invention, the resin composition may use a solvent from the viewpoint of imparting coating properties and the like. When a solvent is used, the solvent does not react with each component in the composition, and can be appropriately selected from solvents in which the components can be dissolved or dispersed. Specific examples of such solvents include, for example, hydrocarbon solvents such as benzene and hexane, ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, tetrahydrofuran, 1,2-dimethoxyethane, propylene glycol monoethyl ether ( Ether solvents such as PGME), halogenated alkyl solvents such as chloroform and dichloromethane, ester solvents such as methyl acetate, ethyl acetate, butyl acetate and propylene glycol monomethyl ether acetate, amide solvents such as N, N-dimethylformamide And sulfoxide solvents such as dimethyl sulfoxide, anone solvents such as cyclohexane, and alcohol solvents such as methanol, ethanol, and propanol, but the invention is not limited thereto. Not to. Moreover, the solvent used for a resin composition may be used individually by 1 type, and the mixed solvent of 2 or more types of solvents may be sufficient.

  It is preferable that it is 20-70 mass%, and, as for the ratio of solid content with respect to resin composition whole quantity, it is more preferable that it is 30-60 mass%.

(5) Other components The resin composition for the fine uneven layer used in the present invention may further contain other components as long as the effects of the present invention are not impaired. Other components include, for example, silicone compounds, fluorine compounds, surfactants for adjusting wettability, stabilizers, antifoaming agents, anti-repelling agents, antioxidants, aggregation inhibitors, viscosity modifiers, A mold release agent etc. are mentioned.
The resin composition for the fine asperity layer preferably contains a silicone compound from the viewpoint of excellent releasability from the original plate for forming fine asperity layer. Here, the silicone-based compound is a compound having a siloxane bond (Si-O-Si) and having an organic group containing at least carbon, and from the point of being easily unevenly distributed on the fine uneven surface of the fine uneven layer, Silicone oil is preferably used.
The silicone oil is not particularly limited. For example, dimethylpolysiloxane, methylphenylpolysiloxane, methylhydrogenpolysiloxane, alkoxy group-containing silicone oil, silanol group-containing silicone oil, vinyl group-containing silicone oil, decamethylcyclopentasiloxane Etc.
In addition, the said silicone type compound may be used individually by 1 type, and may mix and use 2 or more types.

  It is preferable that it is 0.05-3 mass% with respect to the total solid of the resin composition for fine concavo-convex layers, and, as for content of the said silicone type compound, it is more preferable that it is 0.1-2 mass%. . When the content of the silicone-based compound is not less than the lower limit value, the releasability of the resin composition for forming fine asperity layers from the original plate for forming fine asperity layers is improved, and when it is not more than the upper limit value, fine asperities are obtained. Since the moldability of the layer resin composition is improved, it becomes easy to obtain a desired fine uneven shape.

[Fine unevenness shape]
The micro-relief layer has on its surface a micro-relief shape provided with a micro-projection group in which a plurality of micro-protrusions are closely arranged. The shape of the microprotrusions is the cross-sectional area ratio of the material portion forming the microprotrusions in the horizontal cross section when it is assumed that the microprotrusions are cut along a horizontal plane orthogonal to the depth direction of the microprotrusions. However, it is preferable to have a structure that gradually and continuously increases as it approaches from the top to the deepest part of the microprotrusions. As a specific example of the shape of such a microprotrusion, what has perpendicular | vertical cross-sectional shapes, such as semicircle shape, semi-elliptical shape, triangle shape, parabolic shape, a bell shape, etc. is mentioned. The plurality of microprotrusions may have the same shape or different shapes. When the minute projections have the above-mentioned shape, the refractive index is continuously changed in the depth direction of the fine asperities and the like, so that the antireflection performance is improved.

In the present invention, the fine asperity layer further includes one having a plurality of apexes as microprotrusions (hereinafter, may be referred to as "multimodal microprotrusions") from the viewpoint of improving the scratch resistance of the antireflective article. preferable. In addition, the microprotrusions with only one vertex may be referred to as “unimodal microprotrusions” in contrast to multimodal microprotrusions. The multimodal microprotrusions are relatively thicker at the bottom with respect to the dimensions near the apex compared to the unimodal microprotrusions, and furthermore, the external force is dispersed and received at more vertices. It is believed that the external force applied to the apex can be reduced to make the microprotrusion less likely to be damaged. Therefore, in the present invention, mechanical strength and scratch resistance are further improved by including multimodal microprotrusions in the microprotrusions. Further, even if the microprotrusions are damaged, the area of the damaged portion can be reduced, which also reduces the local deterioration of the antireflective function and can further reduce the occurrence of appearance defects. Furthermore, about half of the multimodal microprotrusions occur because the highest peak height (height of the highest peak belonging to the same microprotrusions of the same height) is generated on microprotrusions with an average value H _AVG of projection height or more. First, each peak portion receives and sacrifices damage, thereby preventing wear of the body portion lower than the peaks of the microprojections and the microprojections whose height is lower than that of the multimodal microprojections. This also can reduce local deterioration of the antireflective function and can further reduce the occurrence of appearance defects.
Moreover, the antireflective article according to the present invention has the multimodal microprotrusions as the microprotrusions, whereby the wiping properties are improved. It is considered that this is because when the multimodal microprotrusions are provided, the dirt does not go deep into the root side of the microprotrusions.
In the present invention, each convex part which forms each peak part concerning a multimodal microprotrusion and a unimodal microprotrusion is suitably called "peak".

FIG. 2 is a cross-sectional view (FIG. 2 (a)), a perspective view (FIG. 2 (b)), and a plan view (FIG. 2 (c)) for explaining the multimodal microprotrusion having a plurality of apexes. In addition, this FIG. 2 is a figure typically shown in order to make an understanding easy, and FIG. 2 (a) is a figure which takes and shows a cross section by the broken line which connects the vertex of continuous micro protrusion. In FIGS. 2B and 2C, the xy direction is the in-plane direction of the transparent substrate 1, and the z direction is the height direction of the microprotrusions. In the anti-reflection article 10, many microprotrusions 5 were cut at a cross-sectional area (a plane perpendicular to the height direction (a plane parallel to the XY plane in FIG. 2) gradually away from the transparent substrate 1 toward the apex. The cross-sectional area of the case is reduced to form one vertex. On the other hand, as multimodal microprotrusions, for example, grooves g are formed in the tip portion as if a plurality of microprotrusions are joined, and the number of apexes is two (5A), the number of apexes is three. And those having four or more vertices (not shown), and the like. The shape of the monomodal microprotrusions 5 can be roughly approximated by a round shape at the top like a paraboloid of revolution or a pointed shape at the top like a cone. On the other hand, the shape of the multimodal microprotrusions 5A and 5B is roughly approximated by a shape in which a groove-like concave portion is cut in the vicinity of the top of the unimodal microprotrusion 5 and the top is divided into a plurality of peaks. The main cutting surface shapes of the multimodal microprotrusions 5A and 5B are algebraic curves Z = a ₂ X ² + a ₄ X ⁴ + · · · + a _{2n where} a plurality of maximum points are included and the vicinity of each maximum point is a convex curve. The shape is approximated by X ^{2 n} + ···.

Moreover, an example of a multimodal microprotrusion is shown in FIGS. 20-26, respectively.
FIG. 20 is an enlarged plan view photograph showing an example of multimodal microprotrusions.
FIG. 21 is a perspective view showing an example of the shape of a microprotrusion, and FIG. 22 is a plan view (FIG. 22A) and a front view (FIG. 22B) of the microprotrusion shown in the example of FIG. And a side view (FIG. 22 (c)). 21 and 22 are contour maps. In the microprotrusions shown in FIGS. 21 and 22, three peaks having different heights are combined to form one microprotrusion, and three radial projections formed outward from about the center are formed. The microprotrusions are produced by dividing into the regions related to these three peaks by the ditch (local minimum portion). Note that FIGS. 21 and 22 partially show the data based on the measurement results by the AFM and show them in detail. The unit of numerals in FIGS. 21 and 22 is nm. The X coordinate and the Y coordinate are coordinate values from a predetermined reference position.

  FIG. 23 is a perspective view showing an example of the shape of a microprojection different from that of FIG. 21. FIG. 24 is a plan view of the microprojection shown in the example of FIG. 23 (FIG. 24A). They are a front view (FIG. 24 (b)), and a side view (FIG. 24 (c)). In the microprotrusions shown in FIGS. 23 and 24, three peaks having substantially the same height are combined to create one microprotrusion, and the three peaks extend outward from the substantially central portion of the top. It is divided by three radial grooves.

  FIG. 25 is a perspective view showing an example of the shape of a microprotrusion different from the microprotrusions of FIGS. 21 and 23, and FIG. 26 is a front view of the microprotrusion shown in the example of FIG. a)) and a side view (FIG. 26 (b)). The microprotrusions shown in FIGS. 25 and 26 are formed as if a plurality of microprotrusions arranged side by side in a row are joined, and the aspect ratio is in this arrangement direction and in the direction orthogonal to the arrangement direction. It is made to be different. The antireflective article can be made to have directivity in its antireflective characteristics by the microprojections having different aspect ratios depending on such directions. In the case of the microprotrusions of the eyebrows, the grooves between the ridges extend in the direction orthogonal to the arranging direction.

  According to the results observed in this way, it is observed that the roughness of the surface is rougher than the outer side of each peak on the inner side of each peak in the multimodal microprojection, and the multimodal microprojection is Thus, due to the difference in roughness between the inside and the outside of the peak, it is possible to observe the difference from the multimodal microprotrusions caused by the resin filling failure during the shaping process. In these perspective views and the like, locations where contour lines are not represented are locations where data are not obtained for the convenience of measurement.

  The characteristic of these multimodal microprotrusions is an inherent characteristic of multimodal microprotrusions produced by microholes provided with the corresponding shape of the forming mold, as will be described later. This is a feature that can not be obtained by the multimodal microprotrusions that are generated due to the filling failure of the resin disclosed in Japanese Patent Application Laid-Open No. 0337670. That is, since the multimodal microprotrusions due to the resin filling failure are originally manufactured by the resin being not sufficiently filled in the micropores manufactured as unimodal microprotrusions, the distance between the apexes is extremely small. Thus, it is difficult to sufficiently improve the scratch resistance, and it is also difficult to improve the optical characteristics as described above.

  In addition, multimodal microprotrusions due to poor filling have poor reproducibility and thus can not mass produce uniform products, whereas the multimodal microprotrusions according to this embodiment are so-called High reproducibility can be ensured by the mold. Also, as described later, while control can be performed on the height distribution of the multimodal microprotrusions, such control is difficult for multimodal microprotrusions having poor filling.

  In addition, the microprojection group having a height difference between the heights of the respective microprojections is broadened in anti-reflection performance, and the entire spectrum is provided for light with mixed wavelengths such as white light or light having a broadband spectrum. It is advantageous to realize low reflectance in the band. This is because the wavelength band in which good antireflective performance can be exhibited by such a microprojection group depends not only on the distance between adjacent projections d but also on the height of the projections.

  In addition, when multimodal microprotrusions are mixed, it is possible to improve the anti-reflection performance as compared with the case of using only monomodal microprotrusions, as shown in FIG. In 5A, 5B, etc., even when the distance between adjacent protrusions is the same or when the height of the protrusions is the same, the light reflectance is further reduced as compared with the unimodal micro protrusions. The multimodal microprotrusions 5A, 5B, etc. have a smaller rate of change in the effective refractive index in the height direction in the vicinity of the top than in the monomodal microprotrusions having the same shape below (intermediate and heel) below the top. is there.

  The ratio of the number of multimodal microprotrusions in all the microprotrusions present on the surface is preferably 10% or more and 90% or less, from the viewpoint of exhibiting the above-mentioned effects. It is more preferably 85% or less, and still more preferably 30% to 80%.

Moreover, at least a part of the microprotrusions constituting the micro-concave / convex layer is formed adjacent to the top microprotrusions and the periphery of the top microprotrusions, and a plurality of the microprotrusions are lower in height than the top microprotrusions. A group of microprotrusions consisting of peripheral microprotrusions (hereinafter referred to as “convex-protrusion group” in the present invention) may be formed. By having the set of the microprotrusions, the antireflection performance is improved, and the strength of the microprotrusions is also improved.
FIG. 3 shows a perspective view (FIG. 3 (a)) and a plan view (FIG. 3 (b)) of a convex projection group constituted by a plurality of minute projections. The convex-projections group 24 shown in FIG. 3 includes a top micro-protrusion 3C having a relatively high height and a plurality of peripheral micro-protrusions 3D having a relatively low height disposed adjacent to the periphery thereof. 3 (a) and 3 (b) are schematic views for facilitating understanding, the xy direction is the in-plane direction of the base material, and the z direction is the height of the micro-protrusions. It is
In the present invention, the top micro-protrusions are relatively higher in height than the peripheral micro-protrusions, and have a height difference of 10 nm or more, and the height difference is 20 nm or more. Is preferred. The difference in height is preferably 50 nm or less from the viewpoint of suppressing the feeling of roughness on the surface of the fine uneven layer.

  The fine asperity layer is not particularly limited, but from the viewpoint of further improving the anti-reflection performance, the fine protrusions arranged around the convex protrusion group gradually decrease in height as they move away from the top fine protrusions. It is preferable to arrange so that it may become.

The ratio of the number of micro-protrusions constituting the group of convex projections in all the micro-protrusions present on the surface of the micro-relief layer is not particularly limited, but from 10% to 90% in terms of exerting the effect. It is preferably 30% or more and 85% or less, more preferably 50% or more and 80% or less.
The convex projections do not include microprojections that are adjacent only to the peripheral microprojections and whose height is lower than that of the top microprojections. Further, when the convex projections are formed adjacent to each other, the peripheral microprotrusions may be shared by the adjacent convex projections.
The ratio of the number of microprotrusions constituting the group of convex projections is, for example, the number of microprotrusions among the number of microprotrusions of which the presence can be confirmed by observing the surface of the micro-relief layer by SEM or the like. It can obtain | require by calculating the ratio of the number of objects of the micro protrusion which comprises these.

  The microprotrusions of the microrelief layer may be regularly or irregularly arranged. The measurement and definition of the distance between adjacent protrusions and the height of protrusions when the micro protrusions are irregularly arranged, and the design guidelines thereof will be described with reference to FIGS. 8 to 12. FIG. 8 is an enlarged photograph showing an example of the fine uneven layer of the antireflective article according to the present invention, which is obtained by an atomic force microscope, which is used to explain the fine uneven surface having the fine protrusions. When the microprotrusions are regularly arranged, the microprotrusion distance d can be defined by the repetition period P of the projections. On the other hand, as shown in the example of FIG. 8, when microprotrusions are irregularly arranged, adjacent microprotrusion intervals d have variations. In such a case, the microprojection interval d is calculated as follows.

  (1) First, the in-plane arrangement of projections (projection arrangement) using an atomic force microscope (hereinafter referred to as AFM) or a scanning electron microscope (hereinafter referred to as SEM) Plane shape) of the The data of AFM has in-plane distribution data of the height of the fine uneven layer, and the photograph of FIG. 8 shows the in-plane distribution of the height by the luminance.

  (2) Subsequently, the maximum point (hereinafter simply referred to as a maximum point) of the height of each protrusion is detected from the in-plane arrangement thus determined. The maximum point means a point where the height is larger (maximum value) than any point around the vicinity of the eyebrow. In addition, as a method of obtaining the maximum point, various methods such as a method of obtaining the maximum point by sequentially comparing the planar view shape with the enlarged photograph of the corresponding cross-sectional shape, obtaining the maximum point by image processing of the planar view enlarged photograph, Can be applied. FIG. 9 is a view showing the maximum points of the microprotrusions in the example of the microrelief layer of FIG. The points shown by black dots in FIG. 9 are the maximum points of the respective projections. Each local maximum can be detected by processing the image data of FIG. In this process, the image data is processed in advance by a low pass filter with a Gaussian characteristic of 4.5 × 4.5 pixels, thereby preventing erroneous detection of the maximum point due to noise. Further, the local maximum point was determined in units of 1 nm (= 1 pixel) by sequentially scanning a filter for maximum value detection by 8 pixels × 8 pixels.

  (3) Next, create a Delaunay diagram (Delaunary Diagram) using the detected maximum point as a mother point. Here, with the Delaunay diagram, when Voronoi division is performed with each local maximum point as a generatrix, the mother points adjacent to each other in the Voronoi region are defined as adjacent mother points, and the adjacent mother points are obtained by connecting them with line segments. It is a netlike figure consisting of a set of triangles. Each triangle is called a Delaunay triangle, and a side of each triangle (a line connecting adjacent generation points) is called a Delaunay line. FIG. 10 is a view showing a Delaunay diagram in the example of the fine uneven layer of FIG. Delaunay diagrams are in a dual relationship with Voronoi diagrams. Further, Voronoi division refers to division of a plane by a net-like figure formed of a collection of closed polygons defined by vertical bisectors of line segments (Delaunay lines) connecting between adjacent mother points. A net-like figure obtained by Voronoi division is a Voronoi diagram, and each closed region is a Voronoi region.

  (4) Next, the frequency distribution of the line segment length of each Delaunay line, that is, the frequency distribution of the distance between adjacent maximum points (the distance between adjacent protrusions) is determined. FIG. 11 is a histogram of frequency distribution of distances between adjacent local maximum points created from the Delaunay diagram of FIG. In addition, as shown in 5B of FIG. 9, when there is a recess such as a groove at the top of the protrusion or when the top is divided into a plurality of peaks, such a protrusion is obtained from the obtained frequency distribution. The data resulting from the microstructure having a recess at the top and the microstructure having a top divided into a plurality of peaks is removed, and only the data of the protrusion itself is selected to create a frequency distribution.

  Specifically, in a microstructure having a recess at the top of a protrusion, and a microstructure relating to a multimodal microprojection in which the top is divided into a plurality of peaks, a unimodal not having such a microstructure From the numerical range in the case of microprotrusions, the distance between adjacent local maxima will be significantly different. By removing the corresponding data using this feature, only the data of the projection itself is selected to detect the frequency distribution. More specifically, for example, about 5 to 20 unimodal microprotrusions adjacent to each other are selected from an enlarged photograph of a planar view of the microprotrusions (group) as shown in FIG. (A value which is 1/2 or less of the average value of the distance between adjacent local maximum points determined by sampling normally) The data of (1) is excluded and the frequency distribution is detected. In the example of FIG. 11, data with a distance between adjacent maximum points of 56 nm or less (a small mountain at the left end indicated by arrow A) is excluded. FIG. 11 shows the frequency distribution before such exclusion processing. Incidentally, such exclusion processing may be executed by the setting of the above-mentioned filter for maximum inspection.

(5) The frequency distribution of the distance d between adjacent protrusions obtained in this manner is regarded as a normal distribution to obtain an average value d _AVG and a standard deviation σ _d . In the present invention, the maximum value d _max of the distance d between adjacent protrusions is calculated as d _max = d _AVG + 2σ _d . In the example of FIG. 11, the average value d _AVG = 158 nm and the standard deviation σ _d = 38 nm. Thus, the maximum value d _{max of the} distance d between adjacent projections d is calculated to be 234 nm.

A similar approach is applied to define the height of the protrusions. In this case, the difference in relative height of each local maximum point position from the specific reference position is acquired from the local maximum points determined by the above (2), and a histogram is formed. From the frequency distribution using this histogram, the average value H _AVG of the projection heights and the standard deviation σ _H are determined. When multimodal microprotrusions are included, one microprotrusion has a plurality of apexes, so that a plurality of these data are mixed in the histogram of the projection height H for one protuberance. . Therefore, in this case, the highest point among the plurality of apexes whose ridges belong to the same minute projection is adopted as the projection height of the minute projection to obtain the frequency distribution.
FIG. 12 is a histogram of the frequency distribution of height H of the microprotrusions in the example of the microrelief layer of FIG. In the example of FIG. 12, the root position of the microprotrusions is used as a reference (height 0). In the example of FIG. 12, the average value H _AVG = 178 nm and the standard deviation σ = 30 nm. As a result, in this example, the heights of the protrusions become the average value H _AVG = 178 nm.

  In addition, the reference position in measuring the height of the microprotrusions is based on the position of the projection root, that is, the valley bottom (minimum point of the height) between the adjacent microprotrusions as the reference of the height 0. However, when the height itself of the valley bottom differs depending on the location, for example, the envelope having a series of valley bottoms between the microprotrusions has a convex-concave shape with a larger period than the distance between adjacent protrusions of the microprotrusions ( For example, as shown in the example of FIG. 4, in the case where the height of the valley bottom has an undulation with a large cycle compared to the distance between adjacent protrusions of the microprotrusors, etc.) (1) First, the microprotrusions of the micro uneven layer 30 The average value of the height of each valley bottom measured from the surface opposite to the surface 31 is calculated in an area sufficient for the average value to converge. (2) Next, a plane having the height of the average value and parallel to the surface on the opposite side of the minute projection surface 31 of the minute concavo-convex layer 30 is considered as a reference plane. (3) Thereafter, the height of each of the microprotrusions from the reference surface is calculated, with the reference surface again having a height of 0.

If the height of the valley bottom between adjacent microprotrusions 32 differs depending on the location, for example, as shown in FIG. 4, the envelope connecting the valley bottoms between the microprojections is longer than the longest wavelength λ _MAX of the visible light band. In some cases, undulation occurs with a period D (that is, D> λ _MAX ). The periodical waviness is at a constant height only in one direction (for example, X direction) in a plane (XY plane in FIG. 4) parallel to the front and back surfaces of the transparent substrate and in a direction (for example, Y direction) orthogonal thereto. Alternatively, the two substrates (X and Y directions) may have undulations in a plane (XY plane in FIG. 4) parallel to the front and back surfaces of the transparent substrate. By superimposing the uneven surface 33 having a period D satisfying D> λ _MAX on the surface 31 of the fine uneven layer 30 composed of a large number of fine projections 32, the anti-reflection on the fine uneven layer surface 31 can not be completely prevented. The remaining reflected light can be scattered to further improve the antireflective property.

In addition, when the period D of the uneven surface 33 due to the waviness is not constant over the entire surface but has a distribution, the frequency distribution of the distance between the convexes is obtained for the uneven surface 33, and the average value is D _AVG and the standard deviation When Σ,
D _min = D _AVG-2 Σ
Design as a substitute for the period D with the minimum adjacent projection distance D _min defined as That is, conditions that can sufficiently exhibit the scattering effect of residual reflected light on the surface 31 of the fine uneven layer 30 are as follows:
D _min > λ _MAX
It is. Usually, D or D _min is 1 to 500 μm, preferably 10 to 100 μm.

  Moreover, in order to ensure good smoothness of the antireflective article 10, the height difference (h in FIG. 4) of the uneven surface 33 which is undulated in the period D is preferably 10 nm or less, and 1 nm to 5 nm. It is more preferable to be in the range of On the other hand, when geometric optical scattering of undulations is positively used for reflection prevention, the height difference of the uneven surface 33 undulated by the period D is preferably 0.78 μm or more, and in the range of 1 μm to 10 μm. It is more preferable that it is inside. The height difference of the uneven surface formed by the uneven surface 33 can be obtained by measuring the height difference of the positions of the valley bottoms of the minute projections 32 separated by, for example, 500 nm or more. The position of the valley bottom of the microprotrusions 32 can be determined by observing the antireflective article 10 using a TEM photograph or a SEM photograph of a vertical cross section cut in the thickness direction.

When the microprotrusions in the microprotrusions have the same height H and the microprotrusions are regularly arranged in a constant cycle, the adjacent projection interval d matches the cycle p of the microprotrusion arrangement: d _AVG = p. Therefore, the condition that can exhibit the anti-reflection effect is d _AVG = p ≦ Λ _min , and the anti-reflection effect can be exerted on light having a wavelength of the periodicity p of the micro-projection array or more (for example, 50-70040, Japanese Patent No. 4632589, and Japanese Patent No. 4270806 can be referred to). Therefore, for example, in order to obtain the anti-reflection effect for all wavelengths in the visible light band, when the shortest wavelength in the visible light band is 380 nm, the period of the microprojections array may be 380 nm or less. In addition, the height H of the microprotrusions is preferably 0.2 times or more of the longest wavelength Λ _max among the wavelengths to obtain the anti-reflection effect (H 0.2 0.2 × Λ _max ). Therefore, for example, in order to obtain an excellent antireflection effect for all wavelengths in the visible light band, HH0.2 × 780 nm = 156 nm, assuming that the longest wavelength in the visible light band is 780 nm. Is preferred.

When the protrusions are irregularly arranged, it is necessary that the average value d _{AVG of the} distance d between adjacent protrusions obtained as described above satisfies d _AVG Λ _min , and the maximum value d _max = It is preferable that d _AVG + 2σ _d satisfy d _max ≦ Λ _min . Preferably, the average value H _AVG of the height H of the microprotrusions satisfies H _AVG 0.20.2 × Λ _max . For example, in order to be able to exert an antireflective effect on all wavelengths in the visible light band, d _AVG ≦ 380 nm may be satisfied, and d _max = d _AVG + 2σ _d ≦ 380 nm is preferable. Preferred conditions that can more reliably achieve the antireflective effect for all wavelengths in the visible light band are d _AVG ≦ 300 nm, more preferred conditions are d _max ≦ 300 nm, and even more preferred conditions are d _AVG ≦ 200 nm Particularly preferred conditions are d _max ≦ 200 nm. Further, for reasons such as expression of the anti-reflection effect and securing isotropy (low angle dependency) of the reflectance, normally, d _AVG 50 50 nm, preferably, d _AVG 100 100 nm. With respect to the projection height H, in order to express a sufficient anti-reflection effect, H _AVG波長 0.2 × Λ _max , where 光_max is the longest wavelength of the light wavelength band for anti-reflection It is preferable that H _AVG 0.20.2 × 780 nm = 156 nm, and more preferably H _AVG 170170 nm, in order to exhibit the anti-reflection effect for all wavelengths in the visible light band. The height H _{AVG of the} protrusions is usually 350 nm or less in terms of the anti-reflection effect. Moreover, the distribution of the heights of the protrusions is usually 50 to 350 nm.

One form of anti-reflective article shown in Figure 8 will be described by example above _{d AVG = 158nm ≦ Λ max =} 780nm _{, and} the can can achieve sufficiently antireflection effect satisfies the condition of _{d AVG} ≦ lambda _max I understand. In addition, since the shortest wavelength λ _min of the visible light band is 380 nm, it is understood that the sufficient condition d _AVG ≦ λ _{min for achieving the} anti-reflection effect in the entire wavelength band of visible light is also satisfied. Also an average projection height _H AVG = 178 nm, since it meets the average projection height _{H AVG ≧ 0.2 × λ max =} 156nm ( as the longest wavelength lambda _max = 780 nm in the visible light wavelength range), sufficient reflection It can be seen that the conditions regarding the height of the projections for achieving the prevention effect are also satisfied. Note that, since the standard deviation σ = 30 nm, the relational expression of H _AVG −σ = 148 nm <0.2 × λ max = 156 nm holds, and statistically, 50% or more and 84% or less of all projections are It can be seen that the condition concerning the height of the protrusion (178 nm or more) is satisfied.

When monomodal microprotrusions and multimodal microprotrusions are mixed as in the embodiment shown in the example of FIG. 8, as in the case where monomodal microprotrusions having different aspect ratios are mixed, It is preferable in that low reflectance can be secured in a wide wavelength band.
The aspect ratio is defined as H / W, which is the ratio of the height H of the microprotrusions divided by the diameter W (or width or thickness) at the bottom of the valley. Here, the diameter at the valley bottom corresponds to the (bottom surface) diameter of the cylinder if the shape near the valley bottom of the microprotrusions is a cylinder. If the shape of the bottom of the microprotrusions near the bottom of the microprotrusions is not a cylinder, but the size of the diameter of the bottom surface obtained by crossing the imaginary plane connecting the valley bottoms and the microprotrusions varies depending on the in-plane direction, the maximum value is the microprotrusion And the diameter of For example, when the bottom surface shape of the microprotrusions is an ellipse, the diameter is the major axis of the ridge. In addition, when the bottom shape of the microprotrusions is a polygon, the diameter is the maximum diagonal length. In addition, when the width of the valley bottom (region formed by the minimum point of height) is smaller than the diameter and smaller than 20%, the average value (H / W) ave of the aspect ratio H / W of each microprotrusion is In terms of design, it can be regarded as average protrusion height H _AVG / average adjacent protrusion distance d _AVG .

  The antireflective article according to the present invention can be produced by forming a mold for molding by repeating anodizing treatment and etching treatment, and carrying out a molding process using this mold for molding. Here, in the case of producing micro holes by anodizing treatment, as already known in JP-A-2003-43203 etc., the distance between adjacent micro holes (corresponding to the pitch when there is no distribution at a constant value) There is a proportional relationship with depth. Therefore, the aspect ratio which is the ratio of the width to the height of the root portion is kept approximately constant in the monomodal microprotrusions to be produced.

The anti-reflection function of the anti-reflection article depends not only on the micro-protrusion distance but also on the aspect ratio, and when the aspect ratio is constant, for example, in the visible light range, a sufficiently small reflectance can be ensured. d Since _AVG approaches Λ _min , the reflectance increases and the anti-reflection function is insufficient compared to the visible light range. Note Setting to ensure adequate antireflection function between adjacent protrusions distance further reduced to an ultraviolet region, in turn, since the H _AVG approaches lambda _max, so that the antireflection function in the infrared region is lowered .

  However, in a microprojection group including multimodal microprotrusions, the inter-peak distance present in the vicinity of the top of the same microprotrusion is smaller than the interproximal projection distance (usually about 100 to 200 nm) (usually about 10 to 50 nm). By the contribution of such an inter-peak distance, it is possible to secure an anti-reflection function in which the distance between adjacent adjacent projections is effectively reduced compared to a micro-projection group consisting only of unimodal micro-projections of the same adjacent inter-projection distance. Thus, by combining the multimodal microprotrusions and the unimodal microprotrusions, low reflectance can be secured in a wide wavelength band. When a sufficiently small reflectance is secured in a wide wavelength band centered on the visible light area, the distance between adjacent projections contributing to the antireflection performance for light in the wavelength 480 to 660 nm band related to the visible light area, that is, d ≦ In the microprotrusions where 400 nm, preferably d ≦ 300 nm, it is preferable to mix multimodal microprotrusions and unimodal microprotrusions.

The multimodal microprotrusions formed in the antireflective article may be formed to satisfy the following conditions in order to improve the antireflective function and scratch resistance to incident light in the visible light range described above. preferable.
FIG. 13 is a schematic histogram of the frequency distribution of microprotrusion heights, which serves as an explanation for the low altitude region, the middle altitude region, and the high altitude region with respect to the microprojection height. As shown in FIG. 13, the average value of the height in the frequency distribution of the height H of the microprotrusions is H _AVE , the standard deviation is σ _H, and the region of H <H _AVE -σ _H is the low elevation region of the microprotrusions. If the region of H _AVE −σ _H ≦ H ≦ H _AVE + σ _H is the middle altitude region and the region of H _AVE + σ _H <H is the high altitude region, the number of multimodal microprotrusions in each region It is preferable that the ratio of Nm to the total number Nt of multimodal microprotrusions and unimodal microprotrusions in the entire frequency distribution satisfy the following relationship (a) or (b).
(A) Nm / Nt in medium altitude region> Nm / Nt in low altitude region
(B) Nm / Nt in medium altitude region> Nm / Nt in high altitude region
By satisfying the above relationship, the reflectance for incident light in the visible light range can be reduced, the reflection preventing function of the reflection preventing article can be more specifically broadened, and further, the resistance to the fine uneven surface is further improved. Scratch resistance can be improved.

FIG. 18 shows a histogram of an example of the frequency distribution of the microprojection height H of the antireflective article according to the present invention. In the example shown in FIG. 18, the average value of the heights of the microprotrusions is H _AVE = 145.7 nm, and the standard deviation thereof is σ _H = 22.1 nm.
Here, in the frequency distribution of the height H of the microprotrusions, the low altitude region is H <H _AVE −σ _H = 123.6 nm, and the middle altitude region is H _AVE −σ _H = 123.6 nm ≦ H ≦ H _AVE + σ _H = 167.8 nm, and in the high altitude region, H> H _AVE + σ _H = 167.8 nm.
Since the total number Nt of microprotrusions in the entire frequency distribution is 263, among which the number Nm of multimodal microprotrusions in the middle altitude region is 23, Nm / Nt in the middle altitude region is 0 It will be .087. Since the number Nm of multimodal microprotrusions in the low altitude region is two, the Nm / Nt in the low altitude region is 0.008. Since the number Nm of multimodal microprotrusions in the high altitude region is five, Nm / Nt in the high altitude region is 0.019.
Accordingly, the antireflective article of the example shown in FIG. 18 has the relationship of (a), (b) described above, ie,
(A) Nm / Nt = 0.008> Nm / Nt = 0.008 in the low altitude region
(B) Nm / Nt in the middle altitude region = 0.087> Nm / Nt in the high altitude region = 0.019
Satisfy.

Furthermore, in the antireflective article of the present invention, the frequency distribution of the height H of the microprotrusions is bimodal by two distributions, and the height at the boundary of the two distributions is hs, and the distribution in the distribution less than hs. The average value of height H of the microprotrusions is m1,
Let the region of H <m1-σ1 be the low altitude region,
Let the region of m1-σ1 ≦ H ≦ m1 + σ1 be the middle altitude region,
When the area of m1 + σ1 <H <hs is a high altitude area,
The ratio of the number Nm1 of multimodal microprotrusions in each region in the distribution less than hs to the total number Nt of microprotrusions in the entire frequency distribution satisfies the following relationship (c), (d):
(C) Nm1 / Nt in the medium altitude region> Nm1 / Nt in the low altitude region
(D) Nm1 / Nt in the medium altitude region> Nm1 / Nt in the high altitude region
And, the average value of the height h of the microprotrusions in the distribution of hs or more is m2, and the standard deviation is σ2.
Let the region of hs <H <m2-σ2 be the low altitude region,
Let the region of m 2 −σ 2 ≦ H ≦ m 2 + σ 2 be the middle altitude region,
When the area of m2 + σ2 <H is a high altitude area,
The ratio between the number Nm2 of multimodal microprotrusions in each region in the distribution of hs or more and the total number Nt of microprotrusions in the entire frequency distribution satisfies the following relationship (e) or (f): Is more preferred.
(E) Nm2 / Nt in the medium altitude region> Nm2 / Nt in the low altitude region
(F) Nm2 / Nt in medium altitude region> Nm2 / Nt in high altitude region
By satisfying the above relationship, the reflectance for incident light in the visible light range can be further reduced, and the broadbanding of the antireflection function of the antireflection article can be further specifically realized, and the fine asperity surface can be obtained. Scratch resistance can be further improved.

FIG. 19 shows a histogram of an example of the frequency distribution of the microprojection height H of the antireflective article according to the present invention. In FIG. 19, the microprojection height H and h, and the the H _AVG average projection height m, describes respectively the standard deviation sigma _H sigma. In the example shown in FIG. 19, the height distribution of microprotrusions having a distribution peak on the high side and the low side is discrete, that is, a bimodal distribution, and A distribution of multimodal microprojections is formed corresponding to the peaks. In the example shown in FIG. 19, the average value of the heights of the microprotrusions in the entire frequency distribution is m = 195.7 nm, and the standard deviation is σ = 57.2 nm.
Further, in the example shown in FIG. 19, in the frequency distribution of height h of the microprotrusions, the low altitude region is h <m−σ = 138.5 nm, and the mid altitude region is m−σ = 138.5 nm ≦ h ≦ m + σ = 254.7 nm, and in the high altitude region, h> m + σ = 254.7 nm.
The total number Nt of microprotrusions in the entire frequency distribution is 131. Further, since the number Nm of multimodal microprotrusions in the middle altitude region is 21, the Nm / Nt in the middle altitude region is 0.160. Since the number Nm of multimodal microprotrusions in the low altitude region is 3, Nm / Nt in the low altitude region is 0.023. Since the number Nm of multimodal microprotrusions in the high altitude region is zero, Nm / Nt in the high altitude region is zero.
Therefore, in the example shown in FIG. 19, the relationship between (a) and (b) described above, ie,
(A) Nm / Nt = 0.160 in the middle altitude region> Nm / Nt = 0.023 in the low altitude region
(B) Nm / Nt = 0.160 in the middle altitude region> Nm / Nt = 0 in the high altitude region
Satisfy.

Further, as described above, the frequency distribution of the height h of the microprotrusions shown in FIG. 19 is bimodal, that is, has two distribution peaks. When the height between the peaks is hs, the average value of the height h of the microprotrusions in the distribution less than hs (on the lower side) is m1 = 52.9 nm, and the standard deviation is σ1 = It is 24.8 nm. The boundary of each distribution is determined as hs = 100 nm by statistically processing the data of the height of the frequency distribution.
Therefore, the low altitude region of the distribution less than hs is h <m1−σ1 = 28.1 nm, the medium altitude region is m1−σ1 = 28.1 nm ≦ h ≦ m1 + σ1 = 77.7 nm, and the high altitude region is It becomes m1 + σ1 = 77.7 nm <h <hs = 100 nm.
Further, since the number Nm1 of multimodal microprotrusions in the middle altitude region is two, Nm1 / Nt in the middle altitude region is 0.015. Since the number Nm1 of multimodal microprotrusions in the low altitude region is zero, Nm1 / Nt in the low altitude region is zero. Since the number Nm1 of multimodal microprotrusions in the high altitude region is zero, Nm1 / Nt in the high altitude region is zero.
Accordingly, the antireflective article of the example shown in FIG. 19 has the relationship of (c) and (d) above in the distribution of less than hs, that is,
(C) Nm1 / Nt = 0.015> Nm1 / Nt = 0 in the low altitude region
(D) Nm1 / Nt = 0.015> Nm1 / Nt = 0 in the high altitude region
Meet the relationship.

In addition, for the microprotrusions having a distribution of hs or higher (higher height side), the average value of the height h is m2 = 209.2 nm and the standard deviation is σ2 = 39.4 nm.
Therefore, hs = 100 nm ≦ h <m2-σ2 = 169.9 nm in the low altitude region of the distribution of hs or more, and m2−σ2 = 169.9 nm ≦ h ≦ m2 + σ2 = 248.7 nm in the medium altitude region. The altitude region is m + σ = 248.7 nm <h.
In addition, since the number Nm2 of multimodal microprotrusions in the middle altitude region is 19, the Nm2 / Nt in the middle altitude region is 0.145. Since the number Nm2 of multimodal microprotrusions in the low altitude region is three, Nm2 / Nt in the low altitude region is 0.023. Since the number Nm2 of multimodal microprotrusions in the high altitude region is zero, Nm2 / Nt in the high altitude region is zero.
Accordingly, the antireflective article of the example shown in FIG. 19 has the relationship of the above (e) and (f) even in the distribution of hs or more, ie,
(E) Nm2 / Nt = 0.145 in the medium altitude region> Nm2 / Nt = 0.023 in the low altitude region
(F) Nm2 / Nt = 0.145 in the middle altitude region> Nm2 / Nt = 0 in the high altitude region
Meet the relationship.

The aspect ratio (average protrusion height H _AVG / average adjacent protrusion distance d _AVG ) of the fine protrusions can be 0.8 to 5.0, and in particular, from the viewpoint of the antireflection performance, 0.8 to 2.5 Is preferably, and more preferably 1.0 to 2.1.

  In the present invention, the thickness of the fine uneven layer may be appropriately adjusted. The thickness (T in FIG. 1) of the fine uneven layer 2 can exhibit various performances with the minimum thickness that can form the fine uneven shape on the surface of the transparent substrate 1. However, considering the productivity in the forming process described later, when the thickness is thin, appearance defects due to foreign matter are easily generated, and when the thickness is thick, the forming speed decreases and the concern of curling increases, so 3 μm to 30 μm Is preferably, and more preferably 5 μm to 10 μm. In addition, the thickness of a fine concavo-convex layer means the distance of the perpendicular direction to the substrate plane from the interface by the side of the transparent substrate of a fine concavo-convex layer to the height of the top of the highest microprotrusions.

<Transparent base material>
The antireflective article according to the present invention comprises a transparent substrate as a support. The transparent substrate used in the present invention can be appropriately selected and used according to the application from known transparent substrates used for the antireflective article. Specific examples of the material used for the transparent substrate include polyester resins such as polyethylene terephthalate and polyethylene naphthalate, olefin resins such as polyethylene and polymethylpentene, polyurethane resins, polyether sulfone, polycarbonate, polysulfone, and poly Transparent resin such as ether, polyether ketone, acrylonitrile, methacrylonitrile, cycloolefin polymer, cycloolefin copolymer, glass such as soda glass, potassium glass, lead glass, ceramics such as lead zirconate titanate (PLZT), Transparent inorganic materials such as quartz and fluorite can be mentioned.
Among them, it is preferable that the transparent base material contains a polyester resin as a main component from the viewpoint that generation of outgas is reduced, and among the polyester resins, polyethylene terephthalate is preferable. Here, the main component means a component that occupies 50% by mass or more of the entire base material. The transparent substrate preferably contains a polyester resin in an amount of 80% by mass or more of the entire substrate, more preferably 90% by mass or more, and the polyester resin is preferably polyethylene terephthalate. .

  The transparent substrate preferably has a transmittance of 80% or more, more preferably 90% or more, in the visible light region, from the viewpoint of visibility. Here, the transmittance of the transparent substrate can be measured in accordance with JIS K7361-1 (Plastic-Test Method of Total Light Transmittance of Transparent Material).

  The thickness of the transparent substrate can be appropriately set according to the application of the antireflective article of the present invention, and is supplied in the form of a roll, it does not bend to such an extent that it can be wound, but it bends by applying a load. Although it may be any of those which do not completely bend, and is not particularly limited, it is usually 10 to 5000 μm.

The structure of the transparent substrate used in the present invention is not limited to the structure consisting of a single layer, and may have a structure in which a plurality of layers are laminated. When a plurality of layers are stacked, layers of the same composition may be stacked, or a plurality of layers having different compositions may be stacked.
In addition, a primer layer may be formed on the transparent substrate to improve the adhesion between the transparent substrate and the fine uneven layer and to improve the abrasion resistance (scratch resistance). The primer layer preferably has adhesiveness to the transparent base material and the fine uneven layer adjacent to the transparent base material via the primer layer, and preferably transmits visible light. When interference unevenness occurs due to the difference in refractive index between the transparent base and the fine uneven layer, unevenness can be reduced by adjusting the refractive index of the primer layer to a value intermediate between the transparent base and the fine uneven layer.

The reflectance of the antireflective article according to the present invention is not particularly limited, but is preferably 0.15% or less, and more preferably 0.10% or less.
In the present invention, the light reflectance of the antireflective article is obtained by bonding the transparent substrate side of the antireflective article to be measured to a black acrylic plate via an adhesive, and using a UV-visible spectrophotometer (for example, JASCO Corporation By measuring 5 ° regular reflectance on the surface of the antireflective article using a two-degree field of view (D65 light source) according to JIS Z8701-1999, using a trade name of “V-7100”, etc. , You can ask.

[Method of manufacturing antireflective article]
The antireflective article of the present invention may be formed of a resin composition on a transparent substrate using a resin composition, and may be appropriately selected from conventionally known methods.
In the method for producing an antireflective article according to the present invention, for example, the resin composition for the fine asperity layer is applied on the transparent substrate, and the fine asperity shape of the original plate for forming the fine asperity layer is the resin composition. After forming in the coating film of this, the fine uneven | corrugated layer is formed by hardening the said resin composition, The method of peeling from the said original plate for fine uneven | corrugated layer formation, etc. are mentioned.

The original plate for forming the fine concavo-convex layer is not particularly limited as long as it is not deformed and worn when used repeatedly, and may be metal, resin, ceramic or the like. Although it is good, usually, metal is preferably used. It is because it is excellent in deformation resistance and abrasion resistance. In the case of metal or non-metal, hereinafter, it is referred to as a mold.
The surface having the fine concavo-convex shape of the fine concavo-convex layer forming original plate is not particularly limited, but is preferably made of aluminum from the viewpoint of easy oxidation and easy processing by anodic oxidation.
Specifically, the original plate for forming a fine uneven layer is, for example, aluminum having high purity by sputtering or the like directly or through another layer on the surface of a metal base material such as stainless steel, copper, aluminum or the like. A layer is provided, and what formed fine concavo-convex shape in the aluminum layer concerned is mentioned. The surface of the base material may be ultra-mirror-polished by an electrolytic composite polishing method using a combination of an electrolytic elution action and an abrasion action by abrasives before providing the aluminum layer. The purity of aluminum is usually 99% by weight or more.
Further, the shape of the fine concavo-convex layer forming original plate is not particularly limited as long as it can form a desired shape, and may be, for example, a flat plate, and a roll (hollow cylinder Although it may be in the form of a solid cylinder, the original plate for forming a fine uneven layer may be a roll-shaped mold (hereinafter may be referred to as a "roll mold") from the viewpoint of productivity improvement. It is preferable to use
As a roll mold used in the present invention, for example, a cylindrical metal material is used as a base material, and an aluminum layer provided directly or via various intermediate layers on the circumferential side surface of the base material, As mentioned above, what the fine uneven | corrugated shape was produced by repetition of anodizing treatment and an etching process is mentioned.
As a method of forming a fine concavo-convex shape on the original plate for fine concavo-convex layer formation, for example, an anodic oxidation step of forming a plurality of fine holes on the surface of the aluminum layer by an anodic oxidation method, and etching the aluminum layer The first etching step of forming a tapered shape at the opening of the microhole, and the diameter of the microhole is enlarged by etching the aluminum layer at an etching rate higher than the etching rate of the first etching step. It can form by repeatedly performing 2 etching processes one by one. That is, as shown in FIG. 14, the base material is treated alternately by repeating the anodic oxidation steps A1,..., AN, and the etching steps E1,.
When forming the fine concavo-convex shape, it is possible to obtain a desired shape by appropriately adjusting the purity (amount of impurities) of the aluminum layer, the crystal grain diameter, and various conditions of the anodizing treatment and / or the etching treatment. More specifically, in the anodizing treatment, the minute holes are fabricated to have the shapes corresponding to the intended depth and the shape of the minute projections, respectively, by controlling the liquid temperature, the applied voltage, the time for anodizing, etc. be able to.
In this manner, in the micro-relief layer forming original plate, a large number of micro holes are formed densely in which the hole diameter gradually decreases in the depth direction. In the fine concavo-convex layer manufactured using the fine concavo-convex layer forming original plate, the fine concavities and convexities provided with fine protrusions having a diameter gradually decreasing toward the top are formed corresponding to the fine holes, ie, The cross-sectional area occupancy of the material portion forming the micro-concavity and convexity in the horizontal cross section when it is assumed that the micro-concave is cut along a horizontal plane orthogonal to the depth direction of the micro-concavity and convexity approaches the deepest direction from the top of the micro-concavity and convexity In accordance with the above, a micro-concave / convex shape that gradually and continuously increases is formed.

(Formation process of micro holes forming micro projections)
Next, a method of forming multimodal microprotrusions and forming minute holes in which the distribution of the heights of the microprotrusions is controlled will be described. As described above, the fine holes formed in the molding die (roll plate) are formed by alternately repeating the anodizing treatment and the etching treatment, but the voltage applied in the repetitive anodizing treatment is varied. Thereby, the depth of the micropores (height distribution of microprotrusions) can be controlled. Here, since the applied voltage in the anodizing treatment is in proportion to the interval (pitch) of the micro holes to be formed, the applied voltage of the anodizing treatment can be varied in repetition of the anodizing treatment and the etching treatment. For example, it is possible to control the ratio by mixing fine holes having different time to dig in the depth direction.

  In addition, in the case of varying the applied voltage in the anodizing treatment as described above, a plurality of fine holes are formed on the bottom of a thick fine hole having a large diameter (diameter), and the fine holes pertaining to multimodal fine protrusions are created. It can be done. The height distribution of the multimodal microprotrusions can also be controlled by controlling the height of the thick micropores.

FIG. 15 is a schematic view showing a process of forming the fine holes formed by the manufacturing process of the mold of FIG. 14, and is a schematic view serving to explain control of the height distribution.
As described above, although the relationship between the applied voltage in the anodizing treatment and the pitch of the fine holes is a proportional relation, practically, the pitch of the fine holes varies due to the grain boundary of aluminum to be subjected to the treatment. However, in FIG. 15, it is assumed that the fine holes are produced by the regular arrangement, assuming that this variation does not exist. In Drawing 15 (a)-Drawing 15 (e), the figure on the left shows the enlarged drawing of the surface of a roll metallic mold, and the figure on the right shows aa cross section in the figure on the left.

(First step)
As shown in FIG. 15 (a), first, an anodic oxidation step A1 is performed by applying a voltage V1 to the aluminum layer on the surface of the forming mold, and then an etching step E1 is performed to make fine holes f1. Form. Here, the anodizing step A1 is for producing a trigger for anodizing treatment subsequent to the flat surface of aluminum. In this case, the etching process may be omitted as appropriate.

(Second step)
Next, after an anodic oxidation step A2 is performed by applying a voltage V2 (V2> V1) higher than the voltage V1, an etching step E2 is performed. Thereby, in the anodizing step A2, as shown in FIG. 15 (b), among the fine holes f1 formed in the previous anodizing step A1, the fine holes f1 at the intervals corresponding to the anodizing step A2 are further dug down .
In the present embodiment, in the anodizing step A2, a process of digging every other fine hole f1 formed in the previous anodizing step A1 is performed. Therefore, on the surface of the forming mold, fine holes f2 are formed widely and deeply dug down every other two, and on the surface of the roll plate 13, the fine holes f1 and the fine holes f2 are mixed. Become.

(Third step)
Subsequently, after an anodic oxidation step A3 is performed by applying a voltage V3 (V3> V2) higher than the voltage V2, an etching step E3 is performed. In this process, fine holes with different pitches are produced. Specifically, when the voltage to be applied is gradually raised from the voltage V2 to the voltage V3 and this rise in the applied voltage is performed discretely (stepwisely), the height distribution of the microprotrusions (the distribution of the depths of the micro holes) Can be discretely produced, and the elevation of the microprotrusions can be set to a normal distribution by continuously executing the increase of the applied voltage. Therefore, in the present embodiment, the application time of the applied voltage in the anodizing step A3 and the processing time of the etching step are set longer than the first step and the second step described above, as shown in FIG. As such, the fine holes f1 formed in the first anodizing step A1 are dug widely and deeply so as to be two and one, and the bottom of the fine holes f3 collected in one is substantially flat. (Flat micro hole forming step). Here, substantially flat refers to a state including not only the state in which the bottom of the microhole is flat but also the state in which the bottom is curved with a large radius of curvature.

(4th step)
Subsequently, after an anodic oxidation step A4 is performed by applying a voltage V4 (V4> V3) higher than the voltage V3, an etching step E4 is performed. In this process, a minute hole is created by the pitch according to the target inter-projection distance. Also in the anodic oxidation step A4, the applied voltage is gradually raised from the voltage V3 to the voltage V4. As a result, a part of the micro holes f3 excavated in the third step is further excavated, and as a result, as shown in FIG. 15 (d), the micro holes f4 are formed, and the micro holes f4 have a height Form high unimodal microprojections.

(Fifth step)
Subsequently, after the anodic oxidation step A5 is performed by changing the applied voltage to the voltage V1 in the first step, the etching step E5 is performed. In this step, as shown in FIG. 15 (e), the bottom surface of the fine hole f3 which is the fine hole f3 formed in the anodizing step A3 and which is not affected by the anodizing step A4 in the fourth step. And forming a plurality of micro holes to form micro holes f5 corresponding to the multimodal micro projections (multi-hole projection micro hole forming step). Here, by adjusting the magnitude of the voltage V1 to be applied, it is possible to increase or decrease the number of fine holes formed on the bottom of the fine hole f5, or to adjust the distance between the fine holes.

From the above, on the surface of the forming mold, micro holes f1, f2, f4 forming micro projections different in height, and micro holes f5 forming multimodal micro projections are formed.
Here, in this series of steps, the minute holes f1 and f2 having different depths produced in the first step and the second step are excavated in the third step to form substantially flat minute holes f3 on the bottom surface. In the fourth step, the minute holes f3 are dug-advanced to prepare the minute holes f4 associated with the unimodal microprotrusions, and in the fifth step, the bottom of the minute holes f3 is processed to form many holes. The micro hole f5 which concerns on a peak microprotrusion is produced. Here, controlling the application time, the processing time, the processing time of the etching process, etc. of the anodizing process according to the first to fourth processes, and controlling the depth of the micro holes produced in each process Thus, it is possible to control the distribution of the heights of the microprojections and the distribution of the heights of the multimodal microprojections. In the first to fifth steps described above, the number of times may be omitted, repeated, or the steps may be integrated as necessary.

  FIG. 16 is a schematic view for explaining a process of forming micro holes of different depths involved in the control of the height distribution of the micro protrusions in the manufacturing process of the mold of FIG.

(First step)
Here, as shown in FIG. 16A, in the first step, first, the voltage V1 is applied to the aluminum layer on the surface of the molding die to perform the anodic oxidation step A1, and then the etching step E1. To form fine holes f1. Here, the anodizing step A1 is for producing a trigger for anodizing treatment subsequent to the flat surface of aluminum. In this case, the etching process may be omitted as appropriate.

(Second step)
Next, after an anodic oxidation step A2 is performed by applying a voltage V2 (V2> V1) higher than the voltage V1, an etching step E2 is performed. Thereby, in the anodizing step A2, as shown in FIG. 16 (b), among the fine holes f1 formed in the previous anodizing step A1, the fine holes f1 corresponding to the anodizing step A2 are Dig deeper.

  Here, when the applied voltage V2 is set to V2 = 2 × V1, in the anodic oxidation step A2, a process of digging every other fine hole f1 formed in the previous anodic oxidation step A1 is performed. Therefore, on the surface of the forming mold, fine holes f2 which are widely and deeply dug down are alternately formed, and the fine holes f1 and the fine holes 2 are mixed on the surface of the mold. It becomes a state.

(Third step)
Subsequently, a voltage V3 (V2>V3> V1) between the voltage V1 and the voltage V2 is applied to perform the anodic oxidation step A3, and then the etching step E3 is performed. In this process, fine holes with different pitches are produced. Specifically, the voltage to be applied is a voltage V3, and a specific fine hole f1 as shown in the drawing is dug widely and deeply every other fine hole f1 as shown between the fine holes f2 arranged in the longitudinal and lateral directions. Here, when the applied voltage V3 is set to V3 = (V1) ^1/2 , the application time of the applied voltage in the anodic oxidation step A3 and the processing time of the etching step are set longer than the first step described above. As shown in FIG. 16 (c), among the fine holes f1 formed in the first anodic oxidation step A1, the fine hole f1 located at the center of the smallest square surrounded by the four fine holes f2 is selected. Deeply in depth. At the same time, among the fine holes f2 formed in the second anodic oxidation step A2, part of the fine holes f2 shown in FIG. 16 (c) are further dug down to form fine holes f3.

  As a result, as shown in FIG. 16 (c), the fine holes f2 and f3 (medium) respectively deeper than f1 are present around the fine holes f1 (which will be the holes corresponding to the lowest micro protrusions). And, a mold having a surface structure in which holes surrounded in the plane are arranged in the plane by the holes corresponding to the microprotrusions of a high height) is obtained.

  As described above, since the micro holes to be excavated differ depending on the switching of the applied voltage in a plurality of times of anodizing treatment, the depth of the micro holes can be largely different, and thereby the height of the micro projections is controlled by the intended distribution. can do.

When a photocurable resin composition is used as the resin composition for forming the fine asperity layer in FIG. 5 and a roll mold is used as the original plate for forming the fine asperity layer, the fine asperity layer is formed on the transparent substrate. An example of the method is shown.
In the method shown in FIG. 5, in the resin supplying step, the resin composition for forming the fine uneven layer is applied to the transparent substrate 45 in the form of a belt-like film by the die 41 to form the receiving layer 46 that receives the microprojection shape. . The application method of the resin composition is not limited to the case using the die 41, and various methods can be applied. Subsequently, the transparent substrate is pressed against the peripheral side surface of the roll mold 42, which is a fine concavo-convex layer forming original plate, by the pressure roller 43, thereby closely adhering the receptive layer 46 to the transparent base material. The resin composition which comprises the receiving layer 46 is fully filled in the recessed part of the fine uneven | corrugated shape produced on the 42nd circumferential side. In this state, the resin composition is cured by irradiation of ultraviolet rays, thereby producing a fine uneven layer on the surface of the transparent substrate. Subsequently, the transparent base material is peeled off integrally with the hardened fine asperity layer from the roll mold 42 through the peeling roller 44. After preparing a pressure-sensitive adhesive layer or the like on this transparent base material as necessary, it is cut into a desired size to obtain an antireflective article 10. In this way, the antireflective article sequentially forms the fine concavo-convex shape produced on the circumferential side surface of the roll mold 42, which is a fine concavo-convex layer forming original, on the long transparent base material 45 of the roll material, efficiently Mass produced.

  Moreover, although the above-mentioned embodiment described the case where the film-shaped antireflection article is produced by the forming process using a roll mold, the present invention is not limited to this, and a transparent substrate according to the shape of the antireflection article Depending on the shape of the flat plate, for example, in the case of creating an antireflective article by processing a sheet using a molding die with a specific curved surface shape, a process relating to the molding process, an original plate for forming a micro uneven layer According to the shape of the transparent base material which concerns on the shape of a reflection preventing article, it can change suitably.

<Applications of Antireflection Products>
The antireflective article of the present invention can be applied to various applications in addition to the art display application described later. In each application, the antireflective article of the present invention can prevent light reflection and improve visibility while suppressing the generation of outgassing caused by the antireflective article. Therefore, the antireflective article of the present invention is particularly suitably used in applications where outgas generation tends to be a problem. Specifically, the application of the antireflective article of the present invention is, for example, particularly suitable for, for example, a show window of a store, a product display box, a display window of an exhibition of a museum, an display box, etc. It may be arranged on both the (product or display side) or the back and front (outside side). In this case, while suppressing the generation of outgassing caused by the antireflective article, and suppressing the influence of the outgassing on the exhibits such as goods or works of art, products, works of art, etc. by light reflection prevention of the glass plate surface. It can improve visibility to customers and spectators.

  The antireflective article of the present invention may be further disposed on the indoor side, the outdoor side, or both sides of the window of the cockpit (driver's cab, steering cab) of a vehicle such as a car, railway vehicle, ship or aircraft. Applications that improve outdoor visibility of the driver (driver, steerer) by preventing reflection of indoor and outdoor light at the window; surveillance of crime prevention etc., aiming of guns, lenses or windows of night vision devices used for celestial observation etc. Material used to improve visibility at night and in the dark by arranging it on the surface of wood; Transparent substrates that make up windows, doors, partitions, wall surfaces, etc. of buildings such as houses, stores, offices, schools, and hospitals (window glass Etc.) Placed on the surface (indoor side, outdoor side, both sides of the room) to improve the visibility of the outside world or the light collection efficiency; transparent sheets of greenhouses, greenhouses for agriculture, or transparent plates Arranged on the surface of the window material to improve the light collection efficiency of sunlight Application: Application on solar cell surface to improve utilization efficiency of solar light (power generation efficiency); Touch panel installed on the screen of image display panel with a gap, various window materials, various optical filters, etc. It is disposed on the back side of the front side member (on the image display panel side) to prevent the generation of interference fringes such as a Newton ring due to the interference of light between the image display panel and the front side member. Application to reduce the reflection loss for the prevention of ghost images due to multiple reflections with the light entrance surface side of the side members, and for the image light emitted from the screen and entering the front side members; glasses, telescopes, It is placed on the surface of a lens or prism used for various optical devices such as a camera, video camera, gun aiming mirror (sniper scope), binoculars, periscope, etc. Applications that improve the visibility; It is also applied to the case where it is placed on the surface of the printed part (letters, photographs, figures, etc.) of a book, and uses that prevent light reflection of the surface such as letters and improve the visibility of letters etc. Applications that improve visibility of these signs by placing them on the surface of signboards, posters, bags and other various stores, street and outer walls etc. (route guidance, maps or smoking cessation, entrance, emergency exit, no entry etc.); Arranged on the light entrance surface side of the window material of lighting fixtures using incandescent bulbs, light emitting diodes, fluorescent lamps, mercury lamps, EL (electric field emission) and so on (in some cases, it also serves as a diffusion plate, condenser lens, optical filter etc.) Application to prevent light reflection of the light entrance surface of the window material, reduce reflection loss of light from the light source, and improve light utilization efficiency; Side to prevent light reflection on the surface of these It can also be used in applications such as the above. The antireflective article of the present invention thus improves the visibility in each application, and suppresses the occurrence of outgassing due to the antireflective article, thereby suppressing the influence of the outgassing on the environment around the antireflective article. .

[Art Exhibit]
The art exhibit according to the present invention includes the antireflective article according to the present invention and an art, and the antireflective article is arranged such that the surface having the fine concavo-convex shape faces the side of the art It is characterized by

  The art exhibit according to the present invention is provided with the antireflective article according to the present invention, with the fine asperity surface of the fine asperity layer disposed so as to face the side of the art. Since the antireflective article according to the present invention suppresses the generation of outgassing and has excellent antireflective properties as described above, the art display object according to the present invention suppresses the influence of outgassing on works of art , Excellent in visibility.

6 and 7 are sectional views schematically showing an example of the art display according to the present invention. The art display 50 shown in FIG. 6 includes the anti-reflection article 10 and the art 51 according to the present invention, and is arranged so that the fine uneven surface 2 a of the anti-reflection article 10 faces the art 51 side. An art display 50 shown in FIG. 7 includes two anti-reflection articles 10 according to the present invention and an art item 51. Of the two anti-reflection articles 10, the fine uneven surface 2a is an art item 51. It is disposed to face the side, and the other of the two anti-reflection articles 10 is disposed such that the fine uneven surface 2 a faces the side opposite to the art work 51 side.
The art exhibit according to the present invention may be provided with a storage body 52 for storing the art 51, like the art display 50 shown in FIG. 6 and FIG. Further, the art display object according to the present invention may be provided with a transparent protective plate 53 like an art display object 50 shown in FIG. 6, for example, and as shown in FIG. 7, for example, according to the present invention. The antireflective article 10 may function as a transparent protective plate of a work of art.

In addition, the artwork display according to the present invention may be provided with only one antireflective article according to the present invention as shown in FIG. 6, or according to the present invention as shown in FIG. Two antireflective articles may be provided, and although not shown, three or more antireflective articles according to the present invention may be provided. Moreover, although not shown in the drawings, the art exhibit according to the present invention may be provided with the antireflective article according to the present invention on both sides of the transparent protective plate. Among them, from the viewpoint of suppressing the influence of outgassing on works of art and further improving the visibility, for example, as shown in FIG. 7, an antireflective article in which fine uneven surface 2a is arranged to face art work 51 10, including the anti-reflection article 10 disposed so that the fine uneven surface 2a is on the opposite side to the art work 51 side, that is, the incident side of the external light, the influence of the outgassing on the art work is suppressed. And it is preferable from the point which visibility further improves.
When the art exhibit according to the present invention comprises two or more anti-reflection articles, at least one anti-reflection article is the anti-reflection article according to the present invention and the fine uneven surface 2a faces the art 51 The other antireflective article may be the antireflective article according to the present invention, or a conventional antireflective article different from the antireflective article according to the present invention. You may use.

  There is no particular limitation on the works of art used in the art display according to the present invention, and examples include paintings, calligraphy, sculptures, crafts, photographs and the like. Above all, the art object display according to the present invention is suitably used when a picture having a relatively large influence by outgassing is provided as an art item.

As the storage body 52 used for the artwork display body according to the present invention, any one that is conventionally used as a storage body for works of art can be used, and although not particularly limited, for example, a frame, a housing, a frame Etc.
The material of the storage body is not particularly limited, and examples thereof include glass, resin, metal, wood and the like.
There is no particular limitation on the transparent protective plate 53 used for the art exhibit according to the present invention, but, for example, the same transparent base as that used for the antireflective article according to the present invention can be mentioned.
The art exhibit according to the present invention is particularly preferably used in the case where the airtightness is high and the generated outgas is unlikely to be released from the art exhibit.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has the substantially same constitution as the technical idea described in the claims of the present invention, and the same effects can be exhibited by any invention. It is included in the technical scope of

(Fabrication of original plate for fine asperity layer formation)
After polishing a rolled aluminum plate with a purity of 99.50% so that the surface has an uneven shape with a ten-point average roughness Rz of 30 nm and a period of 1 μm, application is performed in an electrolyte of 0.02 M oxalic acid aqueous solution Anodizing step A1 was performed under the conditions of a voltage of 40 V and a temperature of 20 ° C. for 160 seconds. Next, the etching step E1 was performed for 900 seconds under the condition of 35 ° C. with a phosphoric acid aqueous solution having a concentration of 1.8 mol / L (18 wt%), and was made a first step. Next, as the second step, the anodic oxidation step A2 is performed under the conditions of an applied voltage of 45 V and 20 ° C. for 120 seconds, and then the condition of 35 ° C. with a phosphoric acid aqueous solution having a concentration of 1.8 mol / L (18 wt%) Etching step E2 was performed for 700 seconds. Subsequently, as the third step, the anodic oxidation step A3 is performed under the conditions of an applied voltage of 50 V and 20 ° C. for 90 seconds, and then the condition of 35 ° C. with a phosphoric acid aqueous solution having a concentration of 1.8 mol / L (18 wt%) Etching step E3 was performed for 600 seconds. Subsequently, as the fourth step, the anodic oxidation step A4 is carried out under the conditions of an applied voltage of 55 V and 20 ° C. for 60 seconds, and then the condition of 35 ° C. with a phosphoric acid aqueous solution having a concentration of 1.8 mol / L (18 wt%) Etching step E4 was performed for 300 seconds. Subsequently, as the fifth step, the anodic oxidation step A5 is performed under the conditions of an applied voltage of 60 V and 20 ° C. for 60 seconds, and then the condition of 35 ° C. with a phosphoric acid aqueous solution having a concentration of 1.8 mol / L (18 wt%) Etching step E5 was performed for 300 seconds. Finally, a fluorine-based release agent was applied, and the excess release agent was washed to obtain an original plate for forming a fine uneven layer.

(Preparation of resin compositions A to F for fine asperity layer and resin compositions G and H for comparative fine asperity layer)
The following components were mixed, and methyl ethyl ketone and methyl isobutyl ketone were used as dilution solvents to prepare resin compositions A to F for fine asperity layer with solid content of 45% by mass and resin compositions G, H for comparative fine asperity layer did.

<Resin composition A for fine asperity layer>
EO modified bisphenol A diacrylate 50 mass%
EO modified trimethylolpropane triacrylate 34 mass%
5% by mass of tridecyl acrylate
Dodecyl acrylate 5% by mass
Photoinitiator (Lucillin TPO, manufactured by BASF) 3% by mass
Dimethylpolysiloxane (Shin-Etsu Chemical Co., Ltd. product) 2 mass%
N, N'-dicyclohexylcarbodiimide (Wako Pure Chemical Industries, Ltd.) 1% by mass

<Resin composition B for fine asperity layer>
EO modified bisphenol A diacrylate 50 mass%
EO modified trimethylolpropane triacrylate 34 mass%
Dodecyl acrylate 5% by mass
5% by mass of tridecyl acrylate
Photoinitiator (Lucillin TPO, manufactured by BASF) 3% by mass
Dimethylpolysiloxane (Shin-Etsu Chemical Co., Ltd. product) 2 mass%
Carbodilite V-03 (manufactured by Nisshinbo Chemical Co., Ltd., polycarbodiimide compound, solid content concentration 50% by mass, NCO group content in solid content 0% by mass) 1% by mass

<Resin composition C for fine asperity layer>
EO modified bisphenol A diacrylate 50 mass%
EO modified trimethylolpropane triacrylate 34.5 mass%
Dodecyl acrylate 5% by mass
5% by mass of tridecyl acrylate
Photoinitiator (Lucillin TPO, manufactured by BASF) 3% by mass
Dimethylpolysiloxane (Shin-Etsu Chemical Co., Ltd. product) 2 mass%
Carbodilite V-03 (manufactured by Nisshinbo Chemical Co., Ltd., polycarbodiimide compound, solid content concentration 50% by mass, NCO group content in solid content 0% by mass) 0.5% by mass

<Resin composition D for fine asperity layer>
EO modified bisphenol A diacrylate 50 mass%
EO modified trimethylolpropane triacrylate 34 mass%
5% by mass of tridecyl acrylate
Dodecyl acrylate 5% by mass
Photoinitiator (Lucillin TPO, manufactured by BASF) 3% by mass
Dimethylpolysiloxane (Shin-Etsu Chemical Co., Ltd. product) 2 mass%
Carbodilight V-07 (manufactured by Nisshinbo Chemical Co., Ltd., polycarbodiimide compound, solid content concentration 50% by mass, NCO group content 0.5% by mass in solid content) 1% by mass

<Resin composition E for fine asperity layer>
EO modified bisphenol A diacrylate 50 mass%
EO modified trimethylolpropane triacrylate 33% by mass
5% by mass of tridecyl acrylate
Dodecyl acrylate 5% by mass
Photoinitiator (Lucillin TPO, manufactured by BASF) 3% by mass
Dimethylpolysiloxane (Shin-Etsu Chemical Co., Ltd. product) 2 mass%
Carbodilite V-07 (Nisshinbo Chemical Co., Ltd. product, polycarbodiimide compound, solid content concentration 50 mass%, NCO group content 0.5 mass% in solid content) 2 mass%

<Resin composition F for fine asperity layer>
EO modified bisphenol A diacrylate 50 mass%
EO modified trimethylolpropane triacrylate 30 mass%
5% by mass of tridecyl acrylate
Dodecyl acrylate 5% by mass
Photoinitiator (Lucillin TPO, manufactured by BASF) 3% by mass
Dimethylpolysiloxane (Shin-Etsu Chemical Co., Ltd. product) 2 mass%
Carbodilight V-05 (manufactured by Nisshinbo Chemical Co., Ltd., polycarbodiimide compound, solid content concentration 100% by mass, NCO group content in solid content 8.2% by mass) 5% by mass

<Resin composition G for comparison fine uneven layer>
EO modified bisphenol A diacrylate 50 mass%
EO modified trimethylolpropane triacrylate 35 mass%
5% by mass of tridecyl acrylate
Dodecyl acrylate 5% by mass
Photoinitiator (Lucillin TPO, manufactured by BASF) 3% by mass
Dimethylpolysiloxane (Shin-Etsu Chemical Co., Ltd. product) 2 mass%

<Resin composition H for comparison fine uneven layer>
EO modified bisphenol A diacrylate 50 mass%
EO modified trimethylolpropane triacrylate 25 mass%
5% by mass of tridecyl acrylate
Dodecyl acrylate 5% by mass
Photoinitiator (Lucillin TPO, manufactured by BASF) 3% by mass
Dimethylpolysiloxane (Shin-Etsu Chemical Co., Ltd. product) 2 mass%
Carbodilight V-05 (manufactured by Nisshinbo Chemical Co., Ltd., polycarbodiimide compound, solid content concentration 100% by mass, NCO group content in solid content 8.2% by mass) 10% by mass

Example 1
After curing the composition for primer layer containing urethane acrylate (trade name M-1100, manufactured by Toagosei Co., Ltd., trade name M-1100) and polyethylene terephthalate in polyethylene terephthalate (PET) film (Toray Industries, Inc., U40, thickness 75 μm) To a thickness of 1 μm.
The resin composition A for fine asperity layer is coated and filled so that the fine asperity surface of the original plate for forming asperity layer is covered, and the thickness of the asperity layer after curing is 3 μm, The surface on the primer layer side of the substrate was obliquely bonded, and then the bonded united body was crimped with a rubber roller under a load of 10 N / cm ² . Confirm that the uniform composition is applied to the whole original plate, and irradiate ultraviolet rays with energy of 2000 mJ / cm ² from the transparent substrate side to cure the composition for primer layer and the resin composition for forming micro uneven layer I did. Then, the antireflective article of Example 1 was obtained by peeling from the original plate and forming a fine uneven layer. The fine concavo-convex shape of the fine concavo-convex layer is obtained by closely arranging minute protrusions having a tapered shape with an average height H _AVG of fine protrusions of 250 nm and an average d _AVG of adjacent protrusion intervals of 170 nm. Mixed with multimodal microprotrusions.

Example 2
In Example 1, the antireflective article of Example 2 was obtained in the same manner as Example 1, except that the resin composition B for fine asperity layer was used in place of the resin composition A for fine asperity layer. .

[Example 3]
In Example 1, an antireflective article of Example 3 was obtained in the same manner as in Example 1, except that the resin composition C for fine asperity layer was used in place of the resin composition A for fine asperity layer. .

Example 4
In Example 1, the antireflective article of Example 4 was obtained in the same manner as Example 1, except that the resin composition D for fine asperity layer was used instead of the resin composition A for fine asperity layer. .

[Example 5]
In Example 1, an antireflective article of Example 5 was obtained in the same manner as Example 1, except that the resin composition E for fine asperity layer was used in place of the resin composition A for fine asperity layer. .

[Example 6]
In Example 1, an antireflective article of Example 6 was obtained in the same manner as Example 1, except that the resin composition F for fine asperity layer was used in place of the resin composition A for fine asperity layer. .

Comparative Example 1
An antireflective article of Comparative Example 1 is obtained in the same manner as in Example 1 except that, in Example 1, a resin composition G for comparative fine asperity layer is used in place of the resin composition A for fine asperity layer. The

Comparative Example 2
The antireflective article obtained in Comparative Example 1 was left to stand naturally (23 ° C., 50% RH) for one month to form an antireflective article of Comparative Example 2.

Comparative Example 3
An antireflective article of Comparative Example 3 is obtained in the same manner as in Example 1 except that the resin composition H for comparison fine asperity layer is used instead of the resin composition A for fine asperity layer in Example 1. The
In the antireflective article obtained in Comparative Example 3, the desired fine uneven layer was not formed, and the antireflective function was not exhibited.

[Evaluation]
1. Outgassing concentration analysis by the small chamber method (JISA 1901) The antireflective articles obtained in Examples 1 and 2 and Comparative Examples 1 and 2 were respectively cut into 0.210 m × 0.243 m in size, and used as test bodies. Aldehydes and an organic acid and ammonia were measured by the following method by outgas concentration analysis by a small chamber method (JISA 1901).
The measurement is performed under the conditions of a temperature of 28 ° C., a relative humidity of 50% RH, and a ventilation frequency of 0.5 times / h, an evaluation area of 1.53 m ² , a sample loading rate of 76.5 m ² / m ³ , and a 20 L stainless steel volume It measured about 30 test bodies using the chamber made. The measurement results are shown in Table 1. The sample loading rate refers to the loading rate (m ² / m ³ ) when determining the outgas concentration diffused from the unit area film surface per unit volume (m ³ ), and the sample loading rate in this example is , It calculated | required by the following formula.
Sample loading rate (m ² / m ³ ) = (0.210 m × 0.243 m) × 30 / 0.020 (m ³ )

(Measurement of aldehydes)
Thirty test pieces were placed in a 20 L stainless steel chamber, and high purity air was bubbled under the above conditions, and aldehydes generated from the sample one day later were captured on a DNPH (2,4-dinitrophenylhydrazine) cartridge. Gathered. The DNPH cartridge was eluted with acetonitrile and measured by high performance liquid chromatograph (HPLC). A schematic diagram of the sampling method is shown in FIG.

(Measurement of organic acid, ammonia)
Thirty test pieces were placed in a 20 L stainless steel chamber, high purity air was vented under the above conditions, and gas generated from a sample one day later was collected on an impinger filled with an absorbing solution. The absorption liquid after sampling was measured by ion chromatography (IC). A schematic diagram of the sampling method is shown in FIG.

(Analytical value calculation method)
With respect to formaldehyde, acetaldehyde, formic acid, acetic acid and ammonia in the outgas measured above, the air concentration (volppb) was calculated by the following equation.
Airborne concentration (volppb) = (Airborne concentration (g / m ³ ) x ((273 + sampling temperature (° C)) / 273) x 22.4) / molecular weight Note that the atmospheric concentration (g / m ³ ) is , Calculated by the following equation.
・ Aldehydes:
Concentration in air (g / m ³ ) = Concentration in liquid (g / mL) × elution amount (5 mL) / collection amount (m ³ )
Organic acids, ammonia:
Concentration in air (g / m ³ ) = Concentration of target component in absorbing solution (g / mL) × amount of absorbing solution (mL) / amount collected (m ³ )
A standard was used to determine the airborne concentration of each component. The lower limit of quantification was 1.1 volppb of formaldehyde, 0.71 volppb of acetaldehyde, 6 volppb of formic acid, 5 volppb of acetic acid, and 14 volppb of ammonia. In Table 1, components below the lower limit of quantification were shown as “<lower limit of quantification”.
Moreover, IC measured at the detected formate ion (HCOO ^-) formic acid, acetic acid ion _(CH 3 COO ^-) was converted acetic acid, ammonium ions ^{(NH 4+)} in ammonia was calculated.

2. Concentration Analysis of Organic Acid by Gas Detector Tube The antireflective article obtained in each of the examples and the comparative examples was measured for the concentration of organic acid by the following method which can be measured more simply than the small chamber method. It should be noted that the method has good correlation with the small chamber method and can be relied upon, for example, Chie Sano, 2 others, "evaluation method of reduction measure of organic acid in display case", Conservation Science, Tokyo National Research Institute for Cultural Properties , 2013, No. 53, p. 33-43.
In concentration analysis of organic acid by gas detection tube, sample load factor in desiccator (37.2 L) using Kitagawa type gas detection tube (Koiteiri Chemical Industry Co., Ltd. product, organic acid for art museum, No. 910) The antireflective article was set to 3.3 (m ² / m ³ ), and the organic acid concentration was measured. The suction flow rate was 0.2 L / min for 60 minutes, and the measurement value was 10 ppb or more. The measurement results are shown in Table 2.

3. Measurement of Reflectivity A black tape is attached to the back surface (surface on the substrate side) of the antireflective article obtained in each Example and Comparative Example, and an ultraviolet-visible spectrophotometer (manufactured by JASCO, trade name "V- The regular reflectance of 5 ° to the surface of the antireflective article was measured using a 7100 ′ ′) according to JIS Z8701-1999 with a 2 ° field of view (D65 light source). The measurement results are shown in Table 2.

(Summary of results)
The antireflective articles obtained in Examples 1 to 6 each have the microrelief layer having the microrelief shape specified in the present invention on the surface and containing a specific amount of a compound having a carbodiimide group, Outgassing was suppressed and the anti-reflective property was excellent.
On the other hand, the antireflective article obtained in Comparative Example 1 was inferior in the effect of suppressing the generation of outgassing because the fine uneven layer did not contain the compound having a carbodiimide group.
Further, although the antireflective article obtained in Comparative Example 2 was subjected to so-called drying, compared with the antireflective article obtained in Comparative Example 1, although the occurrence of outgassing was suppressed, the fine uneven layer had a carbodiimide group. Since it did not contain the compound which has, compared with Examples 1-6, it was inferior to the effect which suppresses generation | occurrence | production of outgassing.
In the antireflective article obtained in Comparative Example 3, the resin composition used for the formation of the fine asperity layer is inferior in formability, and the fine asperity shape specified in the present invention may be formed in the fine asperity layer. Because it could not be done, the reflectance was high and it was inferior to the anti-reflection performance.

DESCRIPTION OF SYMBOLS 1 Transparent base material 2 micro uneven | corrugated layer 2a fine uneven | corrugated surface 3 micro protrusion 3C top micro protrusion 3D peripheral micro protrusion 5, 5A, 5B micro protrusion 10 anti-reflective article 24 convex-convex group 30 fine uneven layer 31 fine uneven layer surface 32 micro Protrusions 33 Uneven surface 41 due to waviness Die 42 Roll mold (original plate)
43 Pressure roller 44 Peeling roller 45 Transparent substrate 46 Receptive layer 50 Fine art display 51 Fine art 52 Storage body 53 Transparent protective plate g Groove

Claims (3)

It has a fine concavo-convex shape provided on its surface with a microprotrusion group in which a plurality of microprotrusions are closely arranged on at least one surface of a transparent substrate, and a fine concavo-convex layer made of a cured product of a resin composition is provided. Anti-reflective articles,
The transparent substrate contains a polyester resin,
The microprotrusions have a shortest wavelength in a wavelength band of light for reflection prevention as Λ _min and an average value of the spacing d between adjacent projections of the microprotrusions as d _AVG .
d _AVG Λ _min
Have the relationship
The resin composition is an ionizing radiation curable resin composition containing at least one selected from the group consisting of (meth) acrylate ionizing radiation curable resins, and ethylene oxide modified bisphenol A diacrylate and ethylene oxide modified trimethylol Based on the total solids contained in the resin composition, a compound having a total of 60 to 90% by mass based on the total solids contained in the resin composition and having at least one propane triacrylate and having a carbodiimide group To 0.1% to 5.0% by mass , further containing at least one of tridecyl acrylate and dodecyl acrylate, and containing no monofunctional (meth) acrylate other than tridecyl acrylate and dodecyl acrylate And anti-reflective articles. The total content of tridecyl acrylate and dodecyl acrylate is 5 to 20 parts by mass with respect to 100 parts by mass of the total of ethylene oxide-modified bisphenol A diacrylate and ethylene oxide-modified trimethylolpropane triacrylate. The antireflective article according to 1. An antireflective article according to claim 1 or 2 , and an art item,
The art display object, wherein the anti-reflection article is disposed such that the surface having the fine concavo-convex shape faces the art work side.