JP2010044184A - Transparent molded body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transparent molded body which is excellent in fingerprint wiping-off property and also is excellent in scratch resistance, the transparent molded body having a fine rugged structure of which the pitch is equal to or less than a wavelength of visible light on at least one side surface thereof. <P>SOLUTION: The transparent molded body has the fine rugged structure of which the pitch is equal to or less than a wavelength of visible light on at least one side surface thereof, further has a cover layer which consists of a hydrolysate condensation body of silane coupling agent having a dynamic friction coefficient of 0.2 or less, on the surface of the fine rugged structure and is suitably used for an antireflection article or the like. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a transparent molded body having a fine uneven structure on the surface.

  In recent years, when a concavo-convex structure called a fine moth-eye structure with a period shorter than the wavelength of visible light is provided on the material surface, the refractive index continuously increases from the refractive index of air to the refractive index of the material at the interface between the material and air. Therefore, it is known to be an effective antireflection means.

In addition, there is concern that fingerprints and other dirt may be removed or removed by direct contact with people or objects when the fine concavo-convex structure is exposed to the outside. This is also the case with fluorine-based silane cups on the moth-eye structure. Attempts have been made to solve this problem by forming a layer made of a ring agent to form an oil-repellent material (for example, Patent Document 1). Further, as a similar structure, a super water-repellent material in which a low surface energy material is formed on the surface of a moth-eye structure is also known (for example, Patent Documents 2 and 3).
JP 2000-71290 A Japanese Patent Laid-Open No. 2003-172808 JP 2007-187868 A

However, in Patent Document 1, for example, CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ —SiCl ₃ , CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ —SiCH ₃ Cl ₂ , CF ₃ (CF ₂ ) CH ₂ CH ₂ Specific examples include forming layers of various fluoroalkylsilanes and fluoroalkoxysilanes such as —Si— (OCH ₃ ) _{3. In the} examples, the contact angle of oleic acid is high and the oil repellency is high. It is only stated. In the silane coupling agent layer exemplified in Patent Document 1, although the amount of fingerprint adhesion is reduced, it is difficult to wipe off the adhered fingerprint.

Further, in Patent Documents 2 and 3, there is a problem that since the resin as the low surface energy material is only laminated on the surface, the adhesion is poor and the durability is insufficient.
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a transparent molded article that has excellent fingerprint wiping properties and has improved scratch resistance even when there is a fine concavo-convex structure.

  As a result of intensive studies, the present inventors have formed a coating layer having a specific dynamic friction coefficient on the surface of a fine concavo-convex structure whose period is equal to or less than the wavelength of visible light. It has been found that a transparent molded article having excellent resistance to abrasion and at the same time improving scratch resistance is obtained. That is, the transparent molded body of the present invention has a fine concavo-convex structure whose period is not more than the wavelength of visible light on at least one surface, and a silane coupling agent having a dynamic friction coefficient of 0.2 or less on the surface of the fine concavo-convex structure. It has a coating layer which consists of a hydrolysis-condensation product.

  The present invention relates to a transparent molded body having a fine concavo-convex structure whose period is equal to or less than the wavelength of visible light on at least one surface, and forming a coating layer having a specific dynamic friction coefficient on the surface of the fine concavo-convex structure, thereby wiping the fingerprint. It is possible to provide a transparent molded body having excellent properties and scratch resistance.

  In the present invention, (meth) acrylate means acrylate or methacrylate. Moreover, an active energy ray means visible light, an ultraviolet-ray, an electron beam, plasma, a heat ray (infrared rays etc.), etc.

  As shown in FIG. 1, the transparent molded body of the present invention has a fine concavo-convex structure whose period is not more than the wavelength of visible light on at least one surface, and a coating layer is formed on the surface of the fine concavo-convex structure. The coating layer is composed of a hydrolytic condensate of a silane coupling agent having a dynamic friction coefficient of 0.2 or less. Here, the dynamic friction coefficient of the coating layer refers to a dynamic friction coefficient measured in a state where a coating film is formed on a smooth surface.

<Fine uneven structure>
The fine concavo-convex structure of the present invention has a period equal to or shorter than the wavelength of visible light. This “below the wavelength of visible light” refers to 400 nm or less. If it is larger than 400 nm, visible light scattering occurs, so that it is not suitable for use in an optical application such as an antireflection film. The height (depth) of the fine concavo-convex structure is preferably 50 nm or more, and more preferably 100 nm or more. The reflectance decreases at 50 nm or more. Further, the aspect ratio (= height / cycle) is preferably 0.5 or more, more preferably 1 or more, and most preferably 1.4 or more. Since the reflectance of the transfer product is low at 0.5 or more and the incident angle dependency is also small, a higher value is preferable. The shape of the fine concavo-convex structure is not particularly limited, but for example, in order to obtain an antireflection function that achieves both low reflectance and low wavelength dependency by continuously increasing the refractive index from the air to the material surface, a conical shape, A structure in which the occupation ratio of the cross-sectional area when cutting on the film surface, such as a pyramid shape or a bell shape, continuously increases is preferable. Further, finer protrusions may be combined to form the fine concavo-convex structure.

  The material forming the fine concavo-convex structure of the present invention has a smooth surface and preferably has an elastic modulus of 0.6 GPa or more and 5.0 GPa or less, more preferably 1.3 GPa or more and 4.5 GPa or less, and 2.0 GPa or more and 4.0 GPa or less. Is most preferred. Hydrolysis condensate of silane coupling agent having a dynamic friction coefficient of 0.2 or less according to the present invention because scratch resistance can be obtained by a low load scratch test or a scratch test with few scratches at 0.6 GPa or more and 5.0 GPa or less. As a result, the scratch resistance is further improved. The elastic modulus of the smooth surface can be measured with, for example, an ultra-micro hardness meter manufactured by Fischer Instruments.

<Active energy ray-curable resin composition>
The material for forming the fine concavo-convex structure of the present invention is not particularly limited, such as a thermoplastic resin, a thermosetting resin, glass, a sol-gel inorganic material, a cured product of an active energy ray curable composition, but productivity and freedom of material design. From the point of view, it is preferably made of a cured product of the active energy ray-curable resin composition.

  The active energy ray-curable composition of the present invention contains a polymerizable compound and a polymerization initiator. Examples of the polymerizable compound include monomers, oligomers, and reactive polymers having a radical polymerizable bond and / or a cationic polymerizable bond in the molecule. The active energy ray-curable composition may contain a non-reactive polymer, an active energy ray sol-gel reactive composition.

  Examples of the monomer having a radical polymerizable bond include a monofunctional monomer and a polyfunctional monomer. Monofunctional monomers include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, s-butyl (meth) acrylate, t- Butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, alkyl (meth) acrylate, tridecyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, Phenoxyethyl (meth) acrylate, isobornyl (meth) acrylate, glycidyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, allyl (meth) acrylate, 2-hydroxyethyl ( )) (Meth) acrylate derivatives such as acrylate, hydroxypropyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate; (meth) acrylic acid, (meth) acrylonitrile; styrene, α -Styrene derivatives such as methylstyrene; (meth) acrylamide derivatives such as (meth) acrylamide, N-dimethyl (meth) acrylamide, N-diethyl (meth) acrylamide, dimethylaminopropyl (meth) acrylamide, and the like. These may be used alone or in combination of two or more.

  Polyfunctional monomers include ethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, isocyanuric acid ethylene oxide modified di (meth) acrylate, triethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate , Neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,5-pentanediol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, polybutylene glycol di (Meth) acrylate, 2,2-bis (4- (meth) acryloxypolyethoxyphenyl) propane, 2,2-bis (4- (meth) acryloxyethoxyphenyl) propane, 2,2-bis (4- (3- ( Ta) acryloxy-2-hydroxypropoxy) phenyl) propane, 1,2-bis (3- (meth) acryloxy-2-hydroxypropoxy) ethane, 1,4-bis (3- (meth) acryloxy-2-hydroxypropoxy) ) Butane, dimethylol tricyclodecane di (meth) acrylate, ethylene oxide adduct di (meth) acrylate of bisphenol A, propylene oxide adduct di (meth) acrylate of bisphenol A, neopentyl glycol di (meth) hydroxypivalate Bifunctional monomers such as acrylate, divinylbenzene, and methylenebisacrylamide; pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane ethylene oxide Functional tri (meth) acrylate, trimethylolpropane propylene oxide modified triacrylate, trimethylolpropane ethylene oxide modified triacrylate, isocyanuric acid ethylene oxide modified tri (meth) acrylate and other trifunctional monomers; succinic acid / trimethylolethane / acrylic acid 4 or more functional monomers such as dipentaerystol hexa (meth) acrylate, dipentaerystol penta (meth) acrylate, ditrimethylolpropane tetraacrylate, tetramethylolmethanetetra (meth) acrylate; bifunctional or more Urethane acrylates, bifunctional or higher functional polyester acrylates, and the like. These may be used alone or in combination of two or more.

Examples of the monomer having a cationic polymerizable bond include monomers having an epoxy group, an oxetanyl group, an oxazolyl group, a vinyloxy group, and the like, and a monomer having an epoxy group is particularly preferable.
Examples of the oligomer or reactive polymer include unsaturated polyesters such as a condensate of unsaturated dicarboxylic acid and polyhydric alcohol; polyester (meth) acrylate, polyether (meth) acrylate, polyol (meth) acrylate, epoxy (meth) Examples thereof include acrylates, urethane (meth) acrylates, cationic polymerization type epoxy compounds, homopolymers of the above-described monomers having a radical polymerizable bond in the side chain, and copolymerized polymers.

Non-reactive polymers include acrylic resins, styrene resins, polyurethane resins, cellulose resins, polyvinyl butyral resins, polyester resins, thermoplastic elastomers, and the like.
Examples of the active energy ray sol-gel reactive composition include alkoxysilane compounds and alkylsilicate compounds.

Examples of the alkoxysilane compound include compounds represented by the following general formula (1).

(In the formula, R and R ′ each represent an alkyl group having 1 to 10 carbon atoms, and x and y represent integers satisfying the relationship of x + y = 4.)
Examples of the alkoxysilane compound include tetramethoxysilane, tetra-iso-propoxysilane, tetra-n-propoxysilane, tetra-n-butoxysilane, tetra-sec-butoxysilane, tetra-tert-butoxysilane, methyltriethoxysilane, Examples include methyltripropoxysilane, methyltributoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, trimethylethoxysilane, trimethylmethoxysilane, trimethylpropoxysilane, and trimethylbutoxysilane.

Examples of the alkyl silicate compound include compounds of the following general formula (2).

^(Wherein, R 1 to R ⁴ each represent an alkyl group having 1 to 5 carbon atoms, z represents an integer of 3 to 20.)
Examples of the alkyl silicate compound include methyl silicate, ethyl silicate, isopropyl silicate, n-propyl silicate, n-butyl silicate, n-pentyl silicate, acetyl silicate and the like.

  When using a photocuring reaction, examples of the photopolymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzyl, benzophenone, p-methoxybenzophenone, 2,2-diethoxy. Acetophenone, α, α-dimethoxy-α-phenylacetophenone, methylphenylglyoxylate, ethylphenylglyoxylate, 4,4′-bis (dimethylamino) benzophenone, 2-hydroxy-2-methyl-1-phenylpropane- Carbonyl compounds such as 1-one; sulfur compounds such as tetramethylthiuram monosulfide and tetramethylthiuram disulfide; 2,4,6-trimethylbenzoyldiphenylphosphine oxide, benzoic acid Diethoxy phosphine oxide, and the like. These may be used alone or in combination of two or more.

  When using an electron beam curing reaction, examples of the polymerization initiator include benzophenone, 4,4-bis (diethylamino) benzophenone, 2,4,6-trimethylbenzophenone, methyl orthobenzoylbenzoate, 4-phenylbenzophenone, t- Thioxanthone such as butylanthraquinone, 2-ethylanthraquinone, 2,4-diethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone; diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyl Dimethyl ketal, 1-hydroxycyclohexyl-phenyl ketone, 2-methyl-2-morpholino (4-thiomethylphenyl) propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholy Acetophenone such as phenyl) -butanone; benzoin ether such as benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether; 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,6-dimethoxybenzoyl)- Acylphosphine oxides such as 2,4,4-trimethylpentylphosphine oxide and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide; methylbenzoylformate, 1,7-bisacridinylheptane, 9-phenyl Examples include acridine. These may be used alone or in combination of two or more.

  When a thermosetting reaction is used, examples of the thermal polymerization initiator include methyl ethyl ketone peroxide, benzoyl peroxide, dicumyl peroxide, t-butyl hydroperoxide, cumene hydroperoxide, t-butyl peroxy octoate, organic peroxides such as t-butylperoxybenzoate and lauroyl peroxide; azo compounds such as azobisisobutyronitrile; N, N-dimethylaniline, N, N-dimethyl-p- Examples thereof include a redox polymerization initiator combined with an amine such as toluidine.

  As for the quantity of a polymerization initiator, 0.1-10 mass parts is preferable with respect to 100 mass parts of polymeric compounds. When the amount of the polymerization initiator is less than 0.1 parts by mass, the polymerization is difficult to proceed. When the amount of the polymerization initiator exceeds 10 parts by mass, the cured film may be colored or the mechanical strength may be lowered.

  The active energy ray-curable composition may contain additives such as an antistatic agent and a release agent, fine particles, and a small amount of a solvent, as necessary, as long as the transparency is not impaired and the pigment is not colored.

<Silane coupling agent>
The silane coupling agent used in the coating layer comprising the hydrolyzed condensate of the silane coupling agent of the present invention preferably has a dynamic friction coefficient of 0.2 or less, more preferably 0.18 or less, most preferably 0.15 or less. preferable. Since it is 0.2 or less and the fingerprint wiping property and scratch resistance are exhibited, the lower the value, the better. For example, perfluoropolyether silane CF ₃ CF ₂ CF ₂ (OCF ₂ CF ₂ CF ₂ ) _n 0CF ₂ CF ₂ CH ₂ CH ₂ —Si (OR) ₃ (R is an alkyl group having 4 or less carbon atoms, such as methyl and ethyl. ) Is preferred. n is an integer from 1 to 50, more preferably 3 to 40, and most preferably 10 to 40. If it is smaller than 1, the fingerprint wiping property and scratch resistance may be lowered, and if it is larger than 50, it may not be bonded to the surface of the fine concavo-convex structure at a high density and the fingerprint wiping property and scratch resistance may be lowered. . Moreover, as what can be purchased commercially, Daikin Optool DSX, HD1100, HD2100, Harves Durasurf DS5100, HD4100, Fluoro Technology FG-5010, etc. are mentioned.

  The thickness of the coating layer composed of the hydrolyzed condensate of the silane coupling agent is preferably 0.01 to 20 nm, more preferably 0.1 to 10 nm, and most preferably 0.1 to 5 nm so that the fine uneven structure is maintained. . If it is less than 0.01 nm, uniform coating is difficult. On the other hand, when the thickness is 20 nm or more, the original fine concavo-convex structure is not maintained, and the original antireflection performance may be affected.

<Transparent substrate>
The fine concavo-convex structure may be formed on a transparent substrate. Examples of the transparent substrate include polycarbonate, polystyrene resin, polyester, polyether sulfone, polysulfone, polyether ketone, polyurethane, acrylic resin, and glass. Examples of the shape of the transparent substrate include melt molded products such as films, sheets, injection molded products, and press molded products.

<Manufacturing method>
The manufacturing method of the transparent molded object of this invention will not be specifically limited if the above-mentioned silane coupling agent can be formed into a film on the transparent molded object which has a fine uneven structure. In order to increase the adhesion between the coating layer composed of the hydrolyzed condensate of the silane coupling agent and the fine concavo-convex structure, the material forming the fine concavo-convex structure may be a material having a hydroxyl group or a carboxylic acid group, or a fine concavo-convex structure may be used. A hydroxyl group or a carboxylic acid group may be formed on the surface by corona treatment or plasma treatment. Alternatively, a method of laminating a transparent thin film such as silicon dioxide by a method such as sputtering or vacuum deposition may be used.

  The method for applying the silane coupling agent is not particularly limited, but methods such as micro gravure coat, Mayer bar coat, spin coat, spray coat, dip coat and the like are preferable.

  The concentration of the silane coupling agent is preferably 0.01 to 1.0% by mass, more preferably 0.05 to 0.5% by mass, and most preferably 0.05 to 0.3% by mass. If it is less than 0.01% by mass, it is difficult to coat uniformly, and if it is 0.5% by mass or more, the formed film becomes too thick and the fine uneven structure is not maintained, and the original performance such as antireflection performance may be deteriorated. is there.

  The method for producing the fine concavo-convex structure is not particularly limited, but a method for performing a thermal imprint on a thermoplastic resin using a mold having a fine concavo-convex structure with a period of less than or equal to the wavelength of visible light, or a fine with a period of less than or equal to the wavelength of visible light. Examples thereof include a method of forming a fine uneven structure of a cured product of the active energy ray-curable resin composition on a transparent substrate using a mold having an uneven structure. Examples of a mold having a fine concavo-convex structure with a period equal to or less than the wavelength of visible light include an electron beam lithography method and a laser beam interferometry method. However, the anode can be easily manufactured from a large mold area or a roll-shaped mold. It is preferable to use porous alumina alumina as a mold. In addition, molds made by electron beam lithography or laser beam interferometry are too regular, and the uneven structure of the antireflective article obtained is also highly regular, and interference colors such as blue and purple are seen, but anodized porous Alumina also has an advantage of no interference color because of its low regularity that does not adversely affect other optical performances.

<Transparent molding>
The transparent molded body of the present invention preferably has a water contact angle of 120 ° or more, more preferably 130 ° or more, and most preferably 150 ° or more. If it is 120 ° or more, in addition to the antireflection film, it can be used as a super water-repellent material for automobile exterior materials such as automobile windows, railway vehicle windows, helmets, etc. It can be used for applications such as automobile exterior materials.

<Anti-reflective article>
(Reflectance)
The fine concavo-convex structure may be formed only on one surface of the transparent substrate, or may be formed on both surfaces. In the evaluation of the reflectance when the fine uneven structure is formed only on one surface, the other surface is roughened with sandpaper so that it can absorb light without affecting the reflectance value, Apply a matte black coat and measure relative reflectance. The reflectance at a wavelength of 380 to 780 nm is preferably 0.3% or less, and more preferably 0.25% or less. If it is 0.3% or more, the reflection cannot be sufficiently reduced.

  In the wavelength dependence of the reflectance of the antireflection article of the present invention at a wavelength of 380 to 780 nm, the difference between the maximum reflectance and the minimum reflectance is preferably 0.3 or less, more preferably 0.2 or less, most preferably 0.15 or less. preferable. If it exceeds 0.3, the reflection at a specific wavelength becomes relatively large, so that slightly reflected light appears to be strongly colored.

(Use)
An antireflection article having a fine concavo-convex structure manufactured by the method of the present invention includes an antireflection film, an antireflection film, such as an image display device such as a liquid crystal display device, a plasma display panel, an electroluminescence display, and a cathode tube display device, Examples thereof include an antireflection film, an antireflection film, and an antireflection sheet used on the surface of a half-wave plate, a low-pass filter, a crystal device lens, a show window, a meter panel, and glasses. When used in an image display device, a film may be affixed on the outermost surface or may be formed directly on a material that forms the outermost surface, or may be affixed to a front plate or directly formed on a substrate.

  Examples of the present invention are shown below. However, the present invention is not limited to these. The physical properties in the examples were evaluated according to the following methods.

(1) Pore shape, resin fine concavo-convex shape The mold was formed by depositing platinum on the cross section for 1 minute, and using a field emission scanning electron microscope (manufactured by JEOL Ltd., JSM-7400F) under an acceleration voltage of 3.00 kV. The cross section was observed, and the period of the pores and the depth of the pores were measured. For the resin, platinum was vapor-deposited on the fracture surface for 5 minutes, and the period and the height of the convex portion were measured in the same manner.

(2) Reflectance measurement Using a spectrophotometer (manufactured by Hitachi, Ltd., U-4000) for a molded body in which the back surface of a transparent base material roughened with sandpaper is applied in black to eliminate the influence of back surface reflection. The relative reflectance was measured in the range of an incident angle of 5 ° and a wavelength of 380 to 780 nm. The visibility reflectance was calculated according to JIS R3106.

(3) Contact angle Contact angle measuring device (manufactured by Kruss, “DSA10-Mk2”) was used to measure 11.6 μl of water on the sample surface, and 10 contact angles after 10 seconds were measured at intervals of 1 second. The same operation was performed three times, changing the position where the water was dropped, and the water contact angle was determined by producing the average value.

(4) Coefficient of dynamic friction 99.99% aluminum is electropolished to be mirror-finished and in 0.05M ammonium pentaborate aqueous solution at a temperature of 20 ° C., DC 40V for 60 seconds, 80V for 90 seconds, 120V A smooth anodized alumina layer was formed on the surface by anodizing at 90 seconds, 160 V for 90 seconds, and 200 V for 3 minutes. The obtained anodized alumina layer was washed with deionized water, and then water on the surface was removed by air blow and treated with the following silane coupling agent solution to obtain a sample.

  The frictional resistance test of the above sample was conducted under the conditions of a flat indenter, a vertical load of 200 g, and a sliding speed of 100 mm / min using a HEIDON-14S surface property tester manufactured by Shinto Kagaku Kogyo Co., Ltd., and kinetic friction was performed according to ASTM D 1894 The coefficient was obtained.

[Silane coupling agent A]
Immerse Optool DSX (manufactured by Daikin) in a solution diluted with a diluent HD-ZV (manufactured by Harves) to a solid content of 0.1% by mass for 10 minutes and air dry at 80 ° C. for 5 hours to obtain a sample. It was. The dynamic friction coefficient obtained by the above method was 0.13.

[Silane coupling agent B]
KBM-7803 (manufactured by Shin-Etsu Chemical Co., Ltd.) CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ —Si (OCH ₃ ) ₃ is immersed in a solution diluted with methanol to a solid content of 0.5% by mass and air-dried. Then, a sample was obtained by heat treatment at 120 ° C. for 2 hours. The dynamic friction coefficient obtained by the above method was 0.34.

(5) Fingerprint wiping test After attaching a fingerprint to each sample, the Toray-made Toraysee was thoroughly soaked with tap water to the extent that water droplets do not drip. evaluated.
○: Dirt is not visually recognized.
Δ: Some fingerprints are visually confirmed.
X: The fingerprint spreads and is hardly wiped off.

(6) Scratch resistance test A nell cloth was attached to an indenter having a diameter of 2 cm, a 600-rotation scratch test was performed at a load of 750 g, the back surface was painted black, and the degree of scratching on the surface was evaluated.
○: Up to 3 scratches.
Δ: 3 to 10 scratches.
X: There are 10 or more scratches, or there are planar scratches instead of linear ones.

(7) Elastic modulus of smooth cured film Irradiation with an ultraviolet ray with an integrated light amount equivalent to that when an active energy ray-curable resin composition is filled between an aluminum mirror plate and a film to produce a fine relief structure from the film side. The cured film having no convex portion on the surface was measured using an ultra-micro hardness meter (Fischer Instruments, Fisherscope HM2000) under the following conditions. The integrated amount of ultraviolet light to be irradiated was the same as the integrated amount of ultraviolet light at the time of mold transfer.
Load speed 1 mN / 10 seconds Holding time 10 seconds Load unload speed 1 mN / 10 seconds Indenter Vickers.

[Production Example 1]
Aluminum having a purity of 99.99% was mirror polished by feather polishing and electrolytic polishing in a perchloric acid / ethanol mixed solution (1/4 volume ratio). Next, anodized porous alumina having substantially conical pores with a period of 100 nm and a depth of 180 nm was obtained by the following steps (a) to (e).

Step (a): The aluminum plate was anodized in a 0.3 M oxalic acid aqueous solution for 30 minutes under conditions of a direct current of 40 V and a temperature of 16 ° C.
(B) Process: The aluminum plate in which the oxide film was formed was immersed in 6 mass% phosphoric acid / 1.8 mass% chromic acid mixed aqueous solution for 6 hours, and the oxide film was removed.
Step (c): The aluminum plate was anodized for 30 seconds in a 0.3 M oxalic acid aqueous solution under the conditions of a direct current of 40 V and a temperature of 16 ° C.
(D) Process: The aluminum plate in which the oxide film was formed was immersed in 5 mass% phosphoric acid of 32 degreeC for 8 minutes, and the pore diameter expansion process was performed.
(E) Process: The said (c) process and (d) process were repeated 5 times in total.

  The obtained anodized porous alumina was washed with deionized water, and then water on the surface was removed by air blow, and OPTOOL DSX (manufactured by Daikin) was diluted with diluent HD-ZV so that the solid content was 0.1% by mass. A stamper was obtained by immersing in a solution diluted with Harves Co., Ltd. for 10 minutes and air drying for 20 hours.

[Active energy ray-curable resin composition A]
Trimethylolethaneacrylic acid / succinic anhydride condensation ester 50 parts by mass 1,6-hexanediol diacrylate 30 parts by mass Radical polymerizable silicone oil (X-22-1602, manufactured by Shin-Etsu Chemical Co., Ltd.)
20 parts by mass 1-hydroxycyclohexyl phenyl ketone (Irgacure 184, manufactured by Ciba Specialty Chemicals)
3.0 parts by mass Phenylbis (2,4,6-trimethylbenzoyl) phosphine oxide (Ciba Specialty Chemicals, Irgacure 819)
0.18 parts by mass.

<Example 1>
A few drops of the active energy ray-curable resin composition A is dropped on the surface of the anodized porous alumina produced in Production Example 1, and a polyester film (A4300 thickness 188 μm, manufactured by Toyobo Co., Ltd.) is covered as a transparent substrate. I spread it with a roller so that it would spread.

After irradiating the polyester film side with ultraviolet light with an integrated light quantity of 3000 mJ / cm ² to cure the curable resin composition A, it is cooled to room temperature and separated from the anodized porous alumina, and has a fine uneven structure on the surface. A film was obtained. The period between the convex portions was 100 nm, and the height of the convex portions was 170 nm.

  Next, the film having the fine concavo-convex structure was subjected to a corona treatment using a corona treatment apparatus Polydyne 1 manufactured by Navitas Co., Ltd. at an applied voltage of 11 kv, an electrode-treated workpiece distance of 3 mm, and a treatment speed of 1.7 m / min. The same treatment was performed three times in total, and it was confirmed that the contact angle of the surface was 10 °.

  Next, spin coating is performed using a solution obtained by diluting the silane coupling agent (A) OPTOOL DSX (manufactured by Daikin) with a diluent HD-ZV (manufactured by Harves) so that the solid content is 0.1% by mass. A transparent molded body in which a layer of a silane coupling agent condensate was formed by heat treatment at 80 ° C. for 5 hours was obtained. Table 1 shows the elastic modulus of the smooth cured film, the dynamic friction coefficient, the contact angle of the surface of the fine concavo-convex structure, the scratch resistance test result, and the visibility reflectance.

<Comparative Example 1>
A transparent molded body was obtained in the same manner as in Example 1 except that spin coating was performed using the silane coupling agent (B) and heat treatment was performed at 120 ° C. for 2 hours. Table 1 shows the elastic modulus of the smooth cured film, the dynamic friction coefficient, the contact angle of the surface of the fine concavo-convex structure, the scratch resistance test result, and the visibility reflectance.

<Comparative example 2>
A transparent molded body was obtained in the same manner as in Example 1 except that the hydrolysis condensate layer of the silane coupling agent was not formed. Table 1 shows the elastic modulus of the smooth cured film, the dynamic friction coefficient, the contact angle of the surface of the fine concavo-convex structure, the scratch resistance test result, and the visibility reflectance.

It is a figure in which the coating layer which consists of a hydrolysis condensate of a silane coupling agent is formed in the outermost surface of a fine concavo-convex structure. It is a figure which shows the pore shape of a casting_mold | template.

Explanation of symbols

1 Coating layer 2 Fine uneven structure

Claims (3)

  A coating layer comprising a hydrolyzed condensate of a silane coupling agent having a fine concavo-convex structure with a period not longer than the wavelength of visible light on at least one surface, and a dynamic friction coefficient of 0.2 or less on the surface of the fine concavo-convex structure. Transparent molded body having.   The transparent molded body according to claim 1, wherein the contact angle of water is 120 ° or more.   An antireflection article comprising the transparent molded article according to claim 1 or 2.

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