JPWO2010001763A1 - Optical member and grid polarizing film - Google Patents

Abstract

An optical member having a concavo-convex surface having a concavo-convex structure having a period of 900 nm or less on at least a part of the surface and a protective layer provided on the concavo-convex surface, wherein the protective layer is organic An optical member comprising a material and inorganic fine particles having an average particle size of 100 nm or less; and a grid polarizing film comprising the optical member are provided.

Description

  The present invention relates to an optical member and a grid polarizing film.

  An optical member having a fine concavo-convex structure on the surface has attracted attention in recent years because it exhibits characteristic optical characteristics according to the structure. For example, there have been proposed a member called moth eye in which reflection on the surface is reduced by providing a large number of fine protrusions on the surface, and an optical member such as a wave plate using a sub-wavelength structure. However, since the structure is formed on the surface of the optical member, there is a problem that the scratch resistance is poor.

  Japanese Patent Application Laid-Open No. 2003-302532 proposes an antireflection member in which a hard coat layer is formed on a fine antireflection structure. However, this structure cannot be said to have sufficient scratch resistance and cannot be said to be sufficient as an optical member.

  An object of the present invention is to provide an optical member having an optically useful fine structure and excellent in durability.

  As a result of investigations in view of the above problems, the present inventor has found that the above problems can be solved by adopting an organic layer containing inorganic fine particles having a specific diameter as a layer covering a fine structure. It came to. That is, according to the present invention, the following is provided.

[1] An optical member having a concavo-convex substrate having a concavo-convex structure having a period of 900 nm or less on at least a part of the surface, and a protective layer provided on the concavo-convex surface,
The optical member, wherein the protective layer contains an organic material and inorganic fine particles having an average particle diameter of 100 nm or less.
[2] The optical member, wherein the protective layer has a thickness of 50 nm or less.
[3] The optical member, wherein the concavo-convex structure is a hook-like structure extending in parallel.
[4] The optical member, wherein the uneven substrate has a transparent resin layer and a metal layer extending along the ridge.
[5] The optical member, wherein the organic material of the protective layer is selected from the group consisting of a thermosetting resin, an energy ray curable resin, or a mixture thereof.
[6] A grid polarizing film comprising the optical member.

  The optical member of the present invention is useful as various optical members such as a low reflection member and a grid polarizer because it has a fine structure capable of exhibiting characteristic optical characteristics and is excellent in scratch resistance.

FIG. 1 is a perspective view schematically showing an example of an uneven substrate having a transparent resin layer and a metal layer in the optical member of the present invention. FIG. 2 is a longitudinal sectional view of the concavo-convex substrate shown in FIG. FIG. 3 is a longitudinal sectional view schematically showing another example of the concavo-convex base material having a transparent resin layer and a metal layer in the optical member of the present invention. FIG. 4 is a longitudinal cross-sectional view schematically showing an example of the uneven substrate and the protective layer in the optical member of the present invention.

  The optical member of the present invention has an irregular base material having a predetermined structure and a protective layer containing a predetermined component.

1. Uneven substrate (1-1. Material of uneven substrate)
The material of the concavo-convex substrate can be any material that can function as an optical member, for example, a material that reflects or transmits part of incident light. Specifically, an organic material such as a transparent resin is preferable from the viewpoint of light transmission performance and ease of processing.

Such a transparent resin may be a thermoplastic resin or a cured curable resin, but at least with respect to the wrinkle portion described below, it is curable because it can easily form wrinkles. What hardened | cured resin is preferable.
Transparent thermoplastic resins include polycarbonate resin, polyethersulfone resin, polyethylene terephthalate resin, polyimide resin, polyacrylate resin, polysulfone resin, polyarylate resin, polyethylene resin, polyvinyl chloride resin, cellulose diacetate, cellulose triacetate, An alicyclic olefin polymer etc. are mentioned. Of these, alicyclic olefin polymers are preferred from the viewpoint of transferability.

  The curable resin includes a thermosetting resin and an energy beam curable resin. In addition, an energy ray means visible light, an ultraviolet-ray, an electron beam, an X-ray.

  Specific examples of the thermosetting resin include phenol resin, urea resin, diallyl phthalate resin, melamine resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, aminoalkyd resin, melamine-urea cocondensation resin, silicon resin. And polysiloxane resin.

  Examples of the energy ray curable resin include a low molecular weight compound having a radical polymerizable unsaturated group and / or a cationic polymerizable group, or a resin. In addition, the radically polymerizable unsaturated group and / or the cation polymerizable group may contain two or more in one molecule.

  Examples of the low molecular weight compound having a radical polymerizable unsaturated group include α-olefins such as ethylene and propylene; conjugated diene compounds such as butadiene and isoprene; styrene, α-methylstyrene, t-butylstyrene, divinylbenzene, and vinylnaphthalene. Radical-reactive aromatic compounds such as 4-vinylpyridine; acrylic acid, methacrylic acid, fumaric acid, maleic acid, endo-bicyclo [2.2.1] -5-heptene-2,8-dicarboxylic acid (endic Acid), tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid and other unsaturated carboxylic acids; acrylic acid chloride, methacrylic acid chloride, maleic acid chloride and other unsaturated carboxylic acid halides; acrylamide, methacrylamide, Unsaturated carbo such as maleimide Amide or imide derivatives of acids; anhydrides of unsaturated carboxylic acids such as maleic anhydride, endic anhydride, citraconic anhydride; monomethyl maleate, dimethyl maleate, methyl (meth) acrylate, ethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentenyl ( (Meth) acrylate, allyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, hexanediol di (meth) acrylate, neopen Diglycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tricyclodecane dimethylol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, propionic acid / dipentaerythritol tri (meth) acrylate, propionic acid / Ester derivatives of unsaturated carboxylic acids such as dipentaerythritol tetra (meth) acrylate and dipentaerythritol hexa (meth) acrylate; vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, p-styryltrimethoxysilane, 3 Silane compounds having a radical reaction unsaturated group such as-(meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxytriethoxysilane; and the like.

  Examples of the low molecular weight compound having a cationic polymerizable group include dicyclopentadiene dioxide, (3,4-epoxycyclohexyl) methyl-3,4-epoxycyclohexanecarboxylate, bis (2,3-epoxycyclopentyl) ether, bis (3,4-epoxycyclohexylmethyl) adipate, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate, (3,4-epoxy-6-methylcyclohexyl) methyl-3,4-epoxy-6-methyl Cyclohexane carboxylate, bis (3,4-epoxycyclohexylmethyl) acetal, bis (3,4-epoxycyclohexyl) ether of ethylene glycol, 3,4-epoxycyclohexanecarboxylic acid diester of ethylene glycol, etc. Compounds containing a poxy group; ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, neopentyl glycol diglycidyl ether, 1, Epoxy compounds containing a glycidyl group such as 6-hexanediol diglycidyl ether, glycerin diglycidyl ether, diglycerin tetraglycidyl ether, trimethylolpropane triglycidyl ether, spiroglycol diglycidyl ether; 3-ethyl-3-methoxymethyloxetane 3-ethyl-3-ethoxymethyloxetane, 3-ethyl-3-butoxymethyloxetane, 3-ethyl- -Allyloxymethyloxetane, 3-methyl-3-hydroxymethyloxetane, 3-ethyl-3-hydroxymethyloxetane, 3-ethyl-3- (2'-hydroxyethyl) oxymethyloxetane, 3-ethyl-3- ( 2'-hydroxy-3'-phenoxypropyl) oxymethyloxetane, 3-ethyl-3- (2'-hydroxy-3'-butoxypropyl) oxymethyloxetane, 3-ethyl-3- [2 '-(2 " -Ethoxyethyl) oxymethyl] a compound containing an oxetane ring such as oxetane;

  Examples of the resin having a radical polymerizable unsaturated group or a cationic polymerizable group include low molecular weight polyester resins, polyether resins, acrylic resins, methacrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, Examples thereof include resins having a radically polymerizable unsaturated group or a cationically polymerizable group in the side chain such as a polythiol polyene resin.

  When ultraviolet rays or visible rays are used as energy rays, a photopolymerization initiator, a photosensitizer, or the like is included in the curable resin. Examples of the photopolymerization initiator include acetophenones, benzophenones, Michler benzoylbenzoate, α-amyloxime ester, tetramethylthiuram monosulfide, thioxanthones, and the like. Examples of the photosensitizer include n-butylamine, triethylamine, and tri-n-butylphosphine.

  The transparent resin constituting the concavo-convex base material preferably has a glass transition temperature of 60 to 200 ° C., more preferably 100 to 180 ° C. from the viewpoint of processability. The glass transition temperature can be measured by differential scanning calorimetry (DSC).

  The transparent resin may be appropriately mixed with coloring agents such as pigments and dyes, fluorescent brighteners, dispersants, heat stabilizers, light stabilizers, UV absorbers, antistatic agents, antioxidants, lubricants, solvents, and the like. It may be blended.

  From the viewpoint of durability, the transparent resin is weight from weight W0 after vacuum drying at 100 ° C. for 2 hours to weight W1 after being immersed in warm water at 80 ° C. for 24 hours and then vacuum dried at 100 ° C. for 2 hours. The weight loss is preferably 1% or less of W0, and more preferably 0.8% or less.

  In the present invention, the concavo-convex substrate may be composed of only the transparent resin described above, or may be configured in combination with other materials in addition to the transparent resin. For example, like a grid polarizer described in detail later, a metal layer may be provided in addition to a transparent resin layer, and a combination thereof may be used.

(1-2. Shape of the uneven substrate)
In the present invention, the concavo-convex substrate has a concavo-convex surface having a concavo-convex structure with a period of 900 nm or less on at least a part of the surface thereof.

Here, the period of the concavo-convex structure is the width of one concavo-convex (that is, the length along the one direction) when a plurality of concavo-convex parts having the same shape appear repeatedly when observed along one direction on the concavo-convex surface. Can mean).
When the period of the concavo-convex structure exists in a plurality of directions on the concavo-convex surface, the shortest of them is 900 nm or less, which is included in the category of the present invention, and the preferable effect of the present invention can be obtained. In the following, unless otherwise specified, the shortest cycle is simply called a cycle.

For example, in the case of the concavo-convex base material 310 having the parallel-extending ridge-like structure shown in FIGS. 1 and 2, which will be described in detail later, the period in the concavo-convex structure in which the convex part 310P shown in FIG. It will be the distance shown. In the case where FIG. 2 is a cross section perpendicular to the extending direction of the ridge, the case where the period P2 of the concavo-convex shape observed in FIG. 2 is 900 nm or less is included in the category of the present invention.
The period of the concavo-convex structure is not particularly limited because it varies depending on the performance of the optical member to be manufactured, but is preferably 20 to 800 nm, more preferably 50 to 800 nm, and even more preferably 100 to 400 nm. Thereby, good optical properties and scratch resistance can be imparted.

  The shape of the concavo-convex substrate is not particularly limited as long as it has the concavo-convex surface in at least a part of the surface thereof, but can be usually a film or a plate-like shape, among the main surfaces of the front and back of the film or plate It is preferable that a concavo-convex surface having the concavo-convex structure is provided on at least a part of one side or both sides.

  The average thickness when the concavo-convex base material is in the form of a film is usually 5 μm to 10 mm, preferably 20 to 500 μm from the viewpoint of handleability. The uneven substrate preferably has a light transmittance of 80% or more in the visible light region having a wavelength of 400 to 700 nm.

  In manufacturing the optical member used in the present invention, an elongated base material is preferably used. “Long” means a material having a length of at least about 5 times the width, preferably a material having a length of 10 times or more, and specifically wound and stored in a roll shape. Or what has the length of the grade carried.

  The width of the long uneven substrate is preferably 500 mm or more, more preferably 1000 mm or more. In the course of the manufacturing process, the concavo-convex base material may be arbitrarily cut off (trimming) at both ends in the width direction. In this case, the width of the concavo-convex base material can be a dimension after cutting off both ends.

  The uneven substrate used in the present invention can be obtained by molding the transparent resin by a known method. Examples of the molding method include a cast molding method, an extrusion molding method, and an inflation molding method.

  In the present invention, the specific shape of the concavo-convex structure can be various fine structures capable of exhibiting optical characteristics, but a moth-eye structure having a large number of protrusions on the surface, a structural birefringent wave plate or the following The saddle-like uneven structure that can function as a grid polarizer, which will be described in detail below, can be exemplified.

(1-3. Ridge-like uneven structure)
The ridge-like concavo-convex structure has a plurality of ridges arranged substantially parallel to at least one surface of the concavo-convex substrate. The wrinkle cycle is preferably shorter than the wavelength of visible light. The ridge has a ridge line extending substantially linearly. The vertical cross-sectional shape of the ridge is not particularly limited, and examples thereof include a rectangle, a trapezoid, a diamond, and a mountain.

The height H of the ridge is preferably 5 to 3000 nm, more preferably 20 to 1000 nm, and particularly preferably 50 to 300 nm.
The width of the groove formed between the ribs is preferably 200 nm or less, preferably 20 to 100 nm.
The width of the ridge is preferably 25 to 300 nm, and the length of the ridge (ridge line) is preferably 800 nm or more.
Moreover, the distance (pitch) between the centers of the ridges, that is, the period P2 of the ridges is preferably 20 to 500 nm, more preferably 30 to 300 nm.
The aspect ratio of the ridge (the height of the ridge / the width of the ridge) is preferably 0.1 to 5.0, more preferably 0.4 to 3.0, and particularly preferably 0.8 to 2.0.

  In consideration of optical characteristics such as polarization separation performance, it is preferable that the ridges are arranged approximately in parallel and periodically (at the same pitch). In the present invention, “substantially parallel” means within a range of ± 5 ° from the parallel direction.

  The concavo-convex substrate having the above-described wrinkles can be obtained by a combination of a lithography method and a development etching method, or a transfer method using a transfer mold or a transfer roll. Specifically, an uneven substrate having wrinkles by casting an energy ray curable resin to obtain a coating film, irradiating the coating film with energy rays in a pattern corresponding to wrinkles, and developing the pattern Can be obtained. Also, an energy ray curable resin is cast to obtain a coating film, and a mold or a roll having irregularities corresponding to wrinkles is pressed against the coating film, and the energy beam is applied in the pressed state. Irradiation and curing the energy beam curable resin can provide a concavo-convex substrate having wrinkles.

  In the present invention, in addition to the transparent resin layer described above, the ridge-like uneven structure has a metal layer A at the top of the ridge and / or a metal layer B at the bottom of the groove formed between the ridges. Can be configured. By further including the metal layer A and / or the metal layer B, the optical member of the present invention can be a grid polarizing film.

The material used for the metal layer (grid line) of the grid polarizing film is preferably a conductive material, and specific examples include metals such as aluminum, indium, magnesium, rhodium and tin.
The metal layer can be formed by physical vapor deposition (PVD method) of the material.
The PVD method is a method of forming a film by evaporating and ionizing a vapor deposition material. Specific examples include vacuum deposition, sputtering, ion plating (ion plating), and ion beam deposition. Of these, vacuum vapor deposition is preferred from the viewpoint of easy surface roughness reduction. The vacuum deposition method is a method of forming a thin film by heating and vaporizing or sublimating a deposition material in a vacuumed container and attaching it to the surface of a substrate placed at a remote position. Examples of the heating means include resistance heating, electron beam, high frequency induction, and laser. The atmosphere in the apparatus for performing physical vapor deposition is preferably an absolute pressure of 1 × 10 ⁻² Pa or less, more preferably an absolute pressure of 8 × 10 ⁻³ Pa or less.
The film formation rate by physical vapor deposition is preferably 1.0 nm / second or more, more preferably 2.5 nm / second or more, and particularly preferably 4.0 nm / second or more. In addition, the upper limit of the film forming speed is limited only by the performance of the film forming apparatus, and is not particularly limited from the viewpoint of reducing the surface roughness. By adjusting the film forming speed within this range, the surface roughness can be reduced.

  When a metal layer is formed on the transparent resin substrate having ridges by the PVD method, the metal layer is laminated on the top of the ridge and / or the bottom of the groove formed between the ridges.

  The shape of the metal layer A laminated on the top of the ridge is not particularly limited, and is usually rectangular, trapezoidal, circular, mountain-shaped, or the like. The thickness of the metal layer A is preferably 100 nm or less, more preferably 30 to 100 nm, and particularly preferably 50 to 90 nm from the viewpoint of scratch resistance. By setting it in the above range, the scratch resistance of the grid polarizing film can be improved. The width and length of the metal layer A are generally determined according to the shape of the top surface of the ridge.

  The shape of the metal layer B laminated on the bottom of the groove formed between the ribs is not particularly limited, and is usually rectangular, trapezoidal, circular, or chevron, but the chevron shape is preferable from the viewpoint of optical performance. The thickness of the metal layer B is preferably 100 nm or less, more preferably 30 to 90 nm, and particularly preferably 50 to 80 nm. The width and length of the metal layer B are generally determined according to the shape of the bottom surface of the groove.

  Also, if necessary, in order to form a desired metal layer shape, an inorganic dielectric transparent material is formed by chemical vapor deposition (CVD) or physical vapor deposition (PVD) before forming the metal layer. There is a method in which a metal layer is formed thereafter. Here, silicon dioxide, titanium dioxide, aluminum oxide, or the like can be used as the inorganic dielectric material having transparency.

  Furthermore, in order to improve the adhesion between the base material and the inorganic dielectric, and between the inorganic dielectric and the metal layer, before the inorganic dielectric is sputtered, the surface of the base material is subjected to a plasma treatment as a pretreatment. It can be modified. Examples of the plasma treatment include treatment by ion bombardment using magnetron discharge or treatment by plasma ion shower. By this treatment, the scratch resistance of the optical member can be improved.

  FIG.1 and FIG.2 is the perspective view and sectional drawing which show an example of the uneven | corrugated base material which has a transparent resin layer and a metal layer in this invention. As shown in FIG.1 and FIG.2, it can be set as the structure where the metal layers 311A and 311B of a cross-sectional outline rectangle were each laminated | stacked on both the top part of the rectangular collar 310P, and the space | interval part. Alternatively, as shown in FIG. 3, the metal layer 311B2 in the intercostal space may have a cross-sectional schematic triangle shape. Such a metal layer having a cross-sectional shape such as 311B2 can be obtained by deforming a metal layer formed like the metal layer 311B by means such as etching described in detail below.

  It is preferable to remove a part of the metal layer laminated on the ridge forming surface as described above by wet etching. The part of the metal layer to be removed includes a part formed on the side wall of the ridge, a part protruding from the width of the top of the ridge, and the like. The wet etching includes at least a step of bringing an etching solution into contact with the metal layer, a step of washing with a rinse solution, and a step of removing the rinse solution.

  Before the step of bringing the etching solution into contact with the metal layer, a mask layer may be provided on a portion of the metal layer that is desired not to be removed. In general, an inorganic compound film is used for the mask layer. The mask layer can reduce the thickness of the metal layer by reducing the decrease in the thickness of the metal layer.

  The inorganic compound for masking is not particularly limited as long as it can withstand wet etching described later, and examples thereof include compounds such as silicon dioxide, silicon nitride, silicon carbide, and silicon nitride oxide. Of these, silicon dioxide is particularly preferred. The thickness of the laminated inorganic compound film is not particularly limited, but is usually 1 to 100 nm, preferably 2 to 50 nm, and more preferably 3 to 20 nm. The inorganic compound film can be formed by a PVD method.

  Before the step of bringing the etching solution into contact with the metal layer, the metal layer can be stretched in a direction perpendicular to the ridges arranged in parallel. By this stretching, the distance between the centers of the ridges is increased, the pitch interval between the metal layers A is increased, and as a result, the light transmittance is increased. Moreover, the end of the metal layer B formed on the bottom surface of the groove is separated from the base portion of the ridge by stretching, and a gap is formed. A wet etching solution, which will be described later, enters this gap and removes both ends of the metal layer B preferentially, and as shown in FIG. It can be.

  The stretching method is not particularly limited, but the stretching ratio in the direction perpendicular to the ridge is preferably 1.05 to 5 times, more preferably 1.1 to 3 times, and the stretching ratio in the direction parallel to the ridge is preferably 0.9. It is good to make it -1.1 times, more preferably 0.95-1.05 times. In order to perform such stretching, continuous transverse uniaxial stretching by a tenter stretching machine is suitable.

  Before the step of bringing the etching solution into contact with the metal layer, it is preferable to perform a surface modification treatment of the metal layer. Suitable examples of the surface modification treatment include at least one treatment selected from the group consisting of plasma treatment, corona discharge treatment, UV irradiation treatment, and organic solvent treatment. By performing the surface modification treatment of the metal layer, variation in optical performance is reduced.

  The etching solution used for the wet etching may be a solution that can remove a part of the metal layer without corroding the transparent resin film, and can be used as a material for the mask layer (inorganic compound film), the metal layer, and the transparent resin substrate. It is selected as appropriate. Etching solutions include solutions containing alkali metal compounds such as sodium hydroxide and potassium hydroxide; solutions containing sulfuric acid, phosphoric acid, nitric acid, acetic acid, hydrogen fluoride, hydrochloric acid, etc .; ammonium persulfate, hydrogen peroxide, fluoride Examples include ammonium and the like, and solutions made of a mixture thereof. The etching solution may contain an additive such as a surfactant.

  A method for bringing the etching solution into contact with the metal layer is not particularly limited, but at least one method selected from the group consisting of a dipping method, a spray method, and a coating method is preferable.

The rinsing liquid used for the wet etching is a liquid that removes residues generated when the etching liquid is brought into contact with the metal layer. If the residue remains, the surface of the metal layer becomes rough, which may affect the optical performance. Moreover, a residue may adhere to the unpreferable location of a transparent resin base material.
Examples of the rinse liquid include water (for example, pure water), a solution containing a surfactant, and the like.
The method of cleaning the metal layer with the rinsing liquid is not particularly limited as long as it is a method that can remove the etching liquid and the etching residue that are in contact with the metal layer.

  After washing with the rinse solution, the rinse solution is removed. The method for removing the rinsing liquid is not particularly limited, but an air blow method is preferred.

  The metal layer in the concavo-convex substrate may be provided with a corrosion prevention film by performing a corrosion prevention treatment. From the viewpoint of grid polarization performance, the corrosion prevention film is preferably a monomolecular film or a thickness equivalent thereto, specifically, a thickness of 10 nm or less.

2. Protective layer The optical member of the present invention has a protective layer provided on the uneven surface of the uneven substrate.
The protective layer can be provided on at least a part of the concavo-convex surface of the concavo-convex substrate, but is preferably provided on the entire concavo-convex surface to protect the concavo-convex surface.

  In the present invention, the protective layer can include an organic material and inorganic fine particles having an average particle diameter of 100 nm or less.

(2-1. Organic materials)
The organic material is preferably a transparent resin. The transparent resin can be used as a thermosetting resin, an energy ray curable resin, and a mixture thereof shown as constituting the transparent resin substrate.
As for the organic material made of a transparent resin, the weight loss measured by the same method as described above is preferably 1% or less, and more preferably 0.8% or less, like the transparent resin substrate described above.
The organic material made of a transparent resin preferably has a pencil hardness of 10 μm or more, and more preferably 2H or more. The pencil hardness can be measured according to JIS K5600.

(2-2. Inorganic fine particles)
In the present invention, the inorganic fine particles may have an average particle size of 100 nm or less, preferably 5 to 100 nm.
In the present invention, the average particle diameter is generally determined by laser diffraction method, centrifugal sedimentation light transmission method, X-ray transmission method, electrical detection band method, shading method, ultrasonic attenuation spectroscopy, image processing method, dynamic scattering method, etc. In particular, the laser diffraction method, the image processing method, and the dynamic scattering method are preferably used. In addition, the average particle diameter in this invention shows a number average particle diameter. The inorganic fine particles preferably have an average particle size of 100 nm or less and an aspect ratio of 10 or less, more preferably an average particle size of 50 nm or less and an aspect ratio of 5 or less. By using the inorganic fine particles within the above range, the transparency and mechanical strength of the resulting resin composition can be improved.

  The particle size distribution of the inorganic fine particles is preferably as narrow as possible from the viewpoint of dispersibility, that is, monodisperse or close to monodispersion. The shape of the inorganic fine particles is not particularly limited, and spherical, elliptical, crushed and polyhedral fine particles can be used, but spherical and elliptical shapes are preferable.

  Examples of the inorganic fine particles include inorganic fine particles made of a simple metal, or inorganic fine particles made of a metal oxide or sulfide. From the viewpoint of production, inorganic fine particles made of a metal oxide or sulfide are preferable.

  As a simple metal, Na, K, Mg, Ca, Ba, Al, Zn, Fe, Cu, Ti, Sn, In, W, Y, Sb, Mn, Ga, V, Nb, Ta, Ag, Au, Si , B, Bi, Mo, Ce, Cd, Be, Pb and Ni are preferable, and Al, Sn, Fe, In, Ti, Zn, Zr and Si are more preferable. Moreover, you may use the inorganic compound containing two or more types of metals. Specific examples of metal oxides or sulfides include silicon dioxide (silica), aluminum oxide (alumina), tin oxide, tin disulfide, zinc oxide, zirconium oxide, titanium dioxide, titanium disulfide (eg, rutile, rutile). / Anatase mixed crystal, anatase, amorphous structure), indium oxide, iron oxide, and the like.

  The inorganic fine particles may contain oxides or sulfides of these metals as main components and further contain trace amounts of other elements as impurities. Here, the main component means a component having the largest content (% by weight) among the components constituting the particles. Examples of other elements include Ti, Zr, Sn, Sb, Cu, Fe, Mn, Pb, Cd, As, Cr, Hg, Zn, Al, Mg, Si, P, and S. The impurities may be contained as a single metal or as an oxide.

The inorganic fine particles are directly dispersed as a dispersion by a sol-gel method (described in JP-A Nos. 53-1112732 and 57-9051) or a precipitation method (APPLIED OPTICS, pages 27, 3356 (1998)). Can be synthesized. Further, the powder obtained by the drying / precipitation method can be mechanically pulverized to obtain a dispersion. Commercially available inorganic fine particles (for example, silicon dioxide sol) can also be used.
The compounding amount of the inorganic compound in the protective layer is not particularly limited and can be appropriately adjusted according to the purpose of use, but is preferably 1 to 50% by weight, more preferably 5 to 20% by weight. When the addition amount of the inorganic compound is within this range, the mechanical strength and the moldability are highly balanced, which is preferable.
These inorganic compounds may contain a dispersant in order to improve dispersibility. Although it does not specifically limit as a dispersing agent, A fatty acid, surfactant, and a coupling agent are mentioned. Examples of fatty acids include saturated fatty acids having 4 to 30 carbon atoms such as stearic acid, and unsaturated fatty acids having 4 to 30 carbon atoms such as oleic acid, linoleic acid, and linolenic acid. Examples of surfactants include anionic surfactants such as sodium stearate, sodium lauryl sulfate, sodium dodecylbenzenesulfonate, sodium dioctylsulfosuccinate; cationic surfactants such as N-laurylethanolamine, cetyltrimethylammonium chloride; Nonionic surfactants such as polyoxyethylene nonylphenyl ether, polyoxyethylene stearic acid ester, sorbitan stearic acid ester, polyoxyethylene sorbitan stearic acid ester; amphoteric such as alkylaminocarboxylic acid, hydroxyethyl imidazoline sulfate, imidazoline sulfonic acid Surfactant; Fluorine-based surfactant; Silicone-based surfactant; (Meth) acrylic acid-based surfactant;
Examples of coupling agents include: silane coupling agents such as γ-methacryloxypropyltrimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, hexamethyldisilazane; triisostearoyl isopropyl titanate, di- (Dioctyl phosphate) titanate coupling agents such as diisopropyl titanate; aluminate coupling agents such as monoisopropoxyaluminum monomethacrylate monooleyl acetoacetate and diisopropoxyaluminum monooleyl acetoacetate;

(2-3. Characteristics of protective layer)
An example of the protective layer formed on the uneven surface of the uneven substrate is shown in FIG. FIG. 4 shows a protective layer 420 provided on the bowl-shaped uneven structure shown in FIG. In the example shown in FIG. 4, the thickness of the protective layer 420 is sufficiently thinner than half the gap width 421G1 between the gaps of the concavo-convex structure. As a result, the concavo-convex structure having the gap of the width 421G2 is formed on the surface of the protective layer 420. Is formed. In this way, it is possible to effectively protect the concavo-convex structure without damaging the optical performance of the concavo-convex structure by filling the concavo-convex structure with the protective layer and making the protective layer follow the concavo-convex structure. It becomes.

The average thickness of the protective layer is preferably 50 nm or less, and more preferably 2 to 40 nm in order to protect the concavo-convex structure without impairing the optical performance of the concavo-convex structure as described above. In addition, the average thickness of a protective layer is an average thickness which excludes the convex part of this inorganic fine particle, when some inorganic fine particles appear as a convex part from the protective layer surface. The thickness of the protective layer can be measured by cutting the optical member with an ultramicrotome or the like and observing the cross section with a transmission electron microscope or the like.
The protective layer preferably has a light transmittance in the visible light region with a wavelength of 400 to 700 nm of 80% or more at a thickness of 5 μm.
The relationship between the average thickness (t) of the protective layer and the average diameter (pd) of the inorganic fine particles contained in the protective layer is preferably t: pd = 1: 1.01-1: 10. In view of exhibiting excellent protective properties, it is more preferable that t: pd = 1: 1.04 to 1: 7. In the above relationship, if the average diameter (Pd) of the inorganic particles contained in the protective layer is too large compared to the average thickness (t) of the protective layer, the inorganic particles are likely to be lost, and long-term durability is reduced. It is not preferable. Further, if the average diameter (Pd) of the inorganic fine particles contained in the protective layer is too small compared to the average thickness (t) of the protective layer, the scratch resistance is lowered, which is not preferable.
In addition, the protective layer is a colorant such as a pigment or dye, a fluorescent whitening agent, a dispersing agent, a heat stabilizer, a light stabilizer, an ultraviolet absorber, an antistatic agent, or an antioxidant as long as the effects of the present invention are not impaired. , Chlorine scavengers, flame retardants, crystallization nucleating agents, antifogging agents, mold release agents, organic or inorganic fillers, neutralizing agents, lubricants, decomposition agents, metal deactivators, antifouling agents, fluorescent whitening Agents, antibacterial agents, and other compounding agents may be appropriately blended.

(2-4. Method for forming protective layer)
The protective layer of the present invention can be formed by applying a coating solution prepared by dissolving or dispersing the organic material and inorganic particles in an organic solvent on a concavo-convex substrate, drying, and curing as necessary.
The concavo-convex base material for forming the protective layer preferably has a step of removing organic substances remaining on the surface (surface modification treatment) before forming the protective layer from the viewpoint of forming the protective layer uniformly. Examples of the surface modification treatment include energy ray irradiation treatment and chemical treatment. Examples of the energy ray irradiation treatment include corona treatment, plasma treatment, electron beam irradiation treatment, and ultraviolet ray irradiation treatment. From the viewpoint of processing efficiency, corona treatment and plasma treatment are preferred, and corona treatment is particularly preferred. Examples of the chemical treatment include a method of immersing in an aqueous oxidizing solution such as potassium dichromate solution, concentrated sulfuric acid, or an alkaline aqueous solution such as sodium hydroxide, and then washing with water.
Examples of the organic solvent include aliphatic solvents such as butane, pentane, hexane, heptane, octane, cyclopentane, cyclohexane, decane, and dodecane; aromatic solvents such as toluene, propylbenzene, and benzonitrile; and butyl chloride. Halogen solvents such as amyl chloride, allyl chloride, chlorotoluene; ketone solvents such as diethyl ketone, diisopropyl ketone, methyl hexyl ketone, diisobutyl ketone, butyraldehyde, propyl acetate, butyl acetate, amyl acetate; Ester solvents such as nate, ethyl isobutyrate, butyl butyrate; and the like, dimethyl ether, dihexyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether; Ether-based solvents and the like. These solvents may be used by mixing two or more kinds of solvents.
A method for dissolving or dispersing the organic material, inorganic particles, and organic solvent is not particularly limited, and a homogenizer, a Henschel mixer, a ball mill, a disper, a turbine type stirring blade, and a helical ribbon type stirring blade can be used.
As the coating, a spin coating method, a dipping method, a roll coating method, a spray method, a vapor method, a coater method such as a gravure coater or a blade coater, a screen printing method, an ink jet method or the like can be used.

3. Use of optical member of the present invention (grid polarizer of the present invention)
The optical member of the present invention can be used for various applications corresponding to the optical characteristics of the concavo-convex structure, but can be preferably used as a grid polarizer. In this case, more preferably, an optical element that can be used as a grid polarizer is obtained by using the above-described concave-convex base material having the ridge-like uneven structure and setting the period of the grid to a width capable of obtaining a desired polarization performance. A member can be obtained. More preferably, the etching process described above is performed to obtain a grid polarizer having a cross-sectional structure as shown in FIG.

  Hereinafter, the present invention will be described in more detail based on examples. However, the present invention is not limited to the following examples.

In the following examples, the scratch resistance test was performed as follows.
(Scratch resistance test)
A test sample is fixed on a glass plate with the surface having a protective layer facing up, and a prism sheet (BEFII manufactured by 3M Co., Ltd.) is loaded on the glass plate, and the surface having the structure is loaded on the prism sheet. 10 reciprocating prism sheets were moved at a stroke width of 25 mm and a speed of 30 mm / sec over 200 g / cm ² and scratched. When the test sample is a grid polarizing film, the concave and convex structure of the test sample and the longitudinal direction of the prism sheet structure are arranged in the same direction, and the direction parallel to the surface and perpendicular to the longitudinal direction of the structure are set. The prism sheet was moved in the direction to be made and scratched. On the surface after the scratch treatment, 10 spots were randomly extracted with an area of 2 μm ² and observed with a field emission scanning electron microscope S-4700 (manufactured by Hitachi, Ltd.), and the change in the concavo-convex structure after the scratch resistance test was observed. Evaluation was made according to the following criteria.
Excellent: The uneven structure is not changed at all (the observation point that is not changed is 10/10).
Good: The observation points where the uneven structure is not changed at all are 9/10 to 6/10.
Middle: Observation points where the uneven structure is not changed at all are 5/10 to 3/10 or more.
Impossibility: The observation point where the uneven structure is not changed at all is 2/10 or less.

<Example 1>
(1-1: Preparation of uneven substrate)
An electron beam resist (manufactured by Nippon Zeon, ZEP7000) was applied to a 4-inch silicon wafer at a film thickness of 300 nm. Using an electron beam lithography system ELS-5700 (manufactured by Elionix), a concavo-convex structure in which a conical shape having a height of 250 nm and a bottom surface diameter of 200 nm is arranged in a square lattice with a period of 300 nm in a 30 mm × 30 mm region on the resist layer surface The resist layer was developed.
Nickel electroforming was performed on the surface on which the concavo-convex structure was patterned, and a stamper having a shape with the concavo-convex structure inverted was produced. The stamper was attached to the end plate of the press machine. A sheet of 1 mm thick alicyclic structure polymer (manufactured by Zeon Corporation, ZNR1060R) is hot-pressed at 200 ° C. using a press equipped with the stamper, and the uneven structure is transferred to the sheet surface. An uneven substrate having an uneven surface was obtained.

(1-2: Formation of Protective Layer—Manufacture of Optical Member 1)
While stirring 50 parts by weight of 3-isocyanatopropyltriethoxysilane (manufactured by Shin-Etsu Silicone, KBE-9007) in a reaction vessel, N-2- (aminoethyl) -3-aminopropyltriethoxysilane (manufactured by Shin-Etsu Silicone, (KBE-603) 50 parts by weight were added and reacted until there was no change in the height of 2250 cm ⁻¹ peak (isocyanate group signal) in the FT-IR measurement. Next, the reaction product was diluted with isopropyl alcohol to a solid content concentration of 2% by weight, and 100 parts by weight of the diluted solution was mixed with silica sol slurry of isopropyl alcohol (manufactured by Nissan Chemical Industries, IPA-ST-L, A solid content concentration: 30% by weight, an average particle size (measured by a nitrogen adsorption method): 1.4 parts by weight was added and mixed with a homogenizer to prepare a coating solution.
Next, using a corona treatment device (manufactured by Kasuga Denki) on the concavo-convex surface of the concavo-convex base material prepared in (1-1), an output of 200 W, a wire electrode having a diameter of 1.2 mm, an electrode length of 240 mm, and between work electrodes 1 Discharge treatment was performed once under the conditions of 0.0 mm and a conveyance speed of 5 m / min. Then, after the concavo-convex substrate was immersed in the coating solution for 30 seconds, the optical member 1 was obtained by drying with a dryer at 100 ° C. for 10 minutes.

(1-3: Evaluation of optical member 1)
As a result of measuring the 5 ° reflectance with respect to the wavelength of 550 nm of the produced optical member 1 using a spectrophotometer V-570 (manufactured by JASCO), the reflectance was 1.5%.
Moreover, the observation cross section for transmission electron microscopes (TEM) of the produced optical member 1 was produced using the micro sampling apparatus of the focused ion beam processing observation apparatus FB-2100 (made by Hitachi, Ltd.). As a result of observing the cross section using a transmission electron microscope H-7500 (manufactured by Hitachi, Ltd.) and measuring the thickness of the coating layer, the thickness was 43 nm.
As a result of conducting the scratch resistance test of the optical member 1, the evaluation of the change of the concavo-convex structure was “good”. Furthermore, the reflectance of the optical member 1 after the scratch resistance test was measured in the same manner as described above. As a result, the reflectance after the scratch resistance test was 1.9%, and almost no change was observed in the optical characteristics before and after the scratch resistance test. I couldn't.

<Example 2>
(2-1: Production of metal mold)
A focused ion beam processing device SMI3050 (manufactured by Seiko Instruments Inc.) is used on a 0.2 mm × 1 mm surface of a cuboid single crystal diamond of dimensions 0.2 mm × 1 mm × 1 mm brazed to a SUS shank of 8 mm × 8 mm × 60 mm. Then, focused ion beam processing using an argon ion beam was performed to produce a cutting tool. On a surface of 0.2 mm × 1 mm of the cuboid single crystal diamond on the obtained cutting tool, a groove having a rectangular cross section with a width of 90 nm and a depth of 70 nm parallel to a side of 1 mm in length has a pattern of 160 nm. It was engraved.
The entire surface of a cylindrical surface made of stainless steel SUS430 having a diameter of 200 mm and a length of 500 mm was subjected to nickel-phosphorus electroless plating having a thickness of 100 μm. Next, using a precision cylindrical grinder S30-1 (manufactured by Studer), the cutting tool bite is pressed against the nickel-phosphorus electroless plating surface while rotating the cylinder, and the curved surface is rotated once with a width of 1 mm. Concavities and convexities were formed. The cutting tool was moved in parallel by 1 mm in the length direction of the cylinder, and in the same manner as described above, an uneven strip having a width of 1 mm that goes around the curved surface was formed. This cutting operation was repeated to form a concavo-convex strip having a width of 450 mm on the nickel-phosphorus electroless plating surface of the SUS cylindrical curved surface layer to obtain a transfer roll.

  In addition, the production of the cutting tool by focused ion beam machining and the cutting of the nickel-phosphorus electroless plating surface were controlled by a vibration control system (manufactured by Showa Science Co., Ltd.) with a vibration displacement of 0.5 Hz or more being controlled to 10 μm or less. The measurement was performed in a constant temperature low vibration chamber at a temperature of 20.0 ± 0.2 ° C.

(2-2: Preparation of uneven substrate)
A 100 μm cycloolefin polymer film (ZF-14, manufactured by Optes) between a rubber nip roll having a diameter of 70 mm (surface temperature of 100 ° C.) and the transfer roll (surface temperature of 160 ° C.) was fed with a tension of 0.1 kgf / mm ^2. The nip pressure was 0.5 kgf / mm, and the shape of the transfer roll surface was transferred to the film surface. The film (2-A) was obtained by winding up the film with the transferred shape into a roll. The film (2-A) was cut into a predetermined size, and a TEM observation cross section of the film (2-A) was prepared using a microsampling device of a focused ion beam processing observation device FB-2100 (manufactured by Hitachi, Ltd.). The cross section was taken as the cross section in the surface perpendicular | vertical to the extension direction of the groove | channel on the surface of a film (2-A). As a result of observing the cross section of the film (2-A) with a transmission electron microscope H-7500 (manufactured by Hitachi, Ltd.), the uneven pattern on the film (2-A) has an opening width of 90 nm, a depth of 70 nm, and a period. The rectangular shape was 160 nm.

On the uneven surface side of the film (2-A), an inorganic dielectric layer was formed using a vapor deposition apparatus (heating method: EB heating) equipped with an ion bombardment processing unit using magnetron discharge. An SiO ₂ target is installed in the vapor deposition apparatus, and argon is used as a processing gas. After performing an ion bombardment process under conditions of a processing unit pressure of 10 Pa, a processing time of 10 seconds, and a discharge voltage of 400 V, 5 nm of SiO ₂ is continuously deposited. The film was wound into a roll. Next, the target of the vapor deposition apparatus was replaced with aluminum, and after performing ion bombardment treatment under the same conditions as described above, aluminum was continuously vapor-deposited, and the long aluminum vapor-deposited film ( 2-B) was obtained.

  Next, a composition comprising nitric acid 5.2% by weight, phosphoric acid 73.0% by weight, acetic acid 3.4% by weight, and the balance of water in an etching tank equipped with a heating device and a stirring device (acid component equivalent concentration: 81. 6% by weight) of an etching solution, and a long aluminum vapor-deposited film (2-B) is immersed in an etching bath adjusted to a temperature of 33 ° C. for 25 seconds, and then washed with pure water. The long concavo-convex substrate (2-C) was obtained by removing the rinse liquid by blowing dry air with an air blower.

  The produced concavo-convex base material (2-C) is cut into a predetermined size, and the concavo-convex base material (2-C) is used for TEM by using a microsampling device of a focused ion beam processing observation apparatus FB-2100 (manufactured by Hitachi, Ltd.). An observation cross section was prepared. When the cross section of the concavo-convex substrate (2-C) was observed with a transmission electron microscope H-7500 (manufactured by Hitachi, Ltd.), an aluminum layer was formed on both the convex and concave portions of the concavo-convex surface of the concavo-convex substrate (2-C). It was confirmed that the structure can function as a grid polarizing film.

(2-3: Formation of protective layer-production of optical member (2-D))
Next, the concavo-convex substrate (2-C) prepared in (2-2) is cut into a 10 cm square, and a corona treatment device (manufactured by Kasuga Denki) is used for the concavo-convex surface of the concavo-convex substrate (2-C). The discharge treatment was performed once under the conditions of an output of 50 W, a wire electrode having a diameter of 1.2 mm, an electrode length of 240 mm, a work electrode distance of 1.0 mm, and a conveyance speed of 5 m / min. Then, after immersing the cut-out uneven substrate (2-C) in the coating solution prepared in (1-2) of Example 1 for 5 seconds, the substrate was dried with a dryer at 100 ° C. for 10 minutes to obtain an optical member. (2-D) was obtained.

(2-4: Evaluation of optical member (2-D))
The polarization transmittance and polarization reflectance at a wavelength of 550 nm of the produced optical member (2-D) were measured using a spectrophotometer V-570 (manufactured by JASCO). Note that linearly polarized light is used for the measurement of the polarization transmittance and the polarization reflectance, and the polarization transmittance is measured by measuring the transmittance with the transmission axis of the optical member parallel to the polarization direction of the incident light. Measured the reflectance at an incident angle of 5 ° with the transmission axis of the optical member orthogonal to the polarization direction of the incident light. As a result, the polarization transmittance was 80% and the polarization reflectance was 81%.

  Moreover, the observation cross section for transmission electron microscopes (TEM) of the produced optical member (2-D) was produced using a micro sampling device of a focused ion beam processing observation device FB-2100 (manufactured by Hitachi, Ltd.). As a result of observing the cross section using a transmission electron microscope H-7500 (manufactured by Hitachi, Ltd.) and measuring the thickness of the coating layer, the thickness was 20 nm.

  Next, as a result of conducting a scratch resistance test of the optical member (2-D), the change in the concavo-convex structure was “excellent”. Furthermore, as a result of measuring the optical characteristics of the optical member (2-D) after the scratch resistance test in the same manner as described above, the polarization transmittance after the scratch resistance test was 80% and the polarization reflectance was 81%. There was no change in the optical properties before and after.

<Example 3>
(3-1: Preparation of metal mold)
A focused ion beam processing device SMI3050 (manufactured by Seiko Instruments Inc.) is used on a 0.2 mm × 1 mm surface of a cuboid single crystal diamond of dimensions 0.2 mm × 1 mm × 1 mm brazed to a SUS shank of 8 mm × 8 mm × 60 mm. Then, focused ion beam processing using an argon ion beam was performed to produce a cutting tool. A rectangular parallelepiped groove having a width of 100 nm and a depth of 80 nm parallel to a side of 1 mm in length is formed in a pattern having a period of 200 nm on a 0.2 mm × 1 mm surface of a cuboid single crystal diamond on the obtained cutting tool. It was engraved.
A surface of stainless steel SUS430 having dimensions of 50 mm × 50 mm and a thickness of 10 mm is subjected to nickel-phosphorus electroless plating with a thickness of 100 μm. A metal mold having a predetermined pattern was obtained by cutting the pattern on the cutting tool on the nickel-phosphorous electroless plating surface. In addition, cutting tool fabrication by focused ion beam machining and cutting of nickel-phosphorous electroless plating surface are performed at a temperature of 20.0 ± 0.2 ° C and vibrations of 0.5 Hz or higher by a vibration control system (made by Showa Science). Was carried out in a constant-temperature low-vibration chamber whose displacement was controlled to 10 μm or less.

(3-2: Preparation of uneven substrate)
A coating solution comprising 86.6 parts by weight of isobornyl acrylate, 9.6 parts by weight of dimethylol tricyclodecane diacrylate, and 3.8 parts by weight of a photopolymerization initiator (manufactured by Ciba Specialty Chemicals, Irgacure 184) The surface-modified cycloolefin polymer film (ZF-14, manufactured by Nippon Zeon Co., Ltd.) having a surface modified with a corona treatment was applied at a thickness of 5 μm to obtain a film (3-A) having a coating film. .
The film (3-A) and the metal mold are aligned so that the coating film surface and the pattern surface are in contact, and then the coating film is cured by irradiating with ultraviolet rays from the film side. The film (3-B) having a cured coating film to which the pattern on the metal mold was transferred was obtained. The film (3-B) was cut into a predetermined size, and a TEM observation cross section of the film (3-B) was prepared using a microsampling device of a focused ion beam processing observation device FB-2100 (manufactured by Hitachi, Ltd.). The cross section was a cross section in a plane perpendicular to the extending direction of the grooves on the surface of the film 3. As a result of observing the cross section of the film (3-B) with a transmission electron microscope H-7500 (manufactured by Hitachi, Ltd.), the uneven pattern on the cured coating film of the film (3-B) has an opening width of 100 nm, It was a rectangular shape with a depth of 80 nm and a period of 200 nm.
Next, on the pattern formation surface of the film (3-B), a direction in which SiO ₂ is inclined by 70 degrees from the thickness direction of the film by sputtering under the condition of an output of 400 W in the presence of argon gas (the direction of inclination is the groove on the pattern). The film was obliquely formed from one of the directions orthogonal to the extending direction, and the inclined direction was tilted 70 degrees with the reverse direction (ie, the other direction orthogonal to the extending direction of the grooves on the pattern). Similarly, SiO ₂ was obliquely formed from the direction, and then aluminum was formed from the vertical direction of the film by vacuum deposition to obtain a film (3-C).
Next, a composition comprising nitric acid 5.2% by weight, phosphoric acid 73.0% by weight, acetic acid 3.4% by weight, and the balance of water in an etching tank equipped with a heating device and a stirring device (acid component equivalent concentration: 81. 6% by weight) of the etching solution, the film (3-C) was immersed in an etching bath adjusted to a temperature of 33 ° C. for 25 seconds, washed with pure water, and dried with an air blower. The concavo-convex substrate (3-D) was obtained by removing the rinse liquid by blowing air.
The produced concavo-convex base material (3-D) is cut into a predetermined size, and the concavo-convex base material (3-D) is used for TEM by using a microsampling device of the focused ion beam processing observation apparatus FB-2100 (manufactured by Hitachi, Ltd.). An observation cross section was prepared. When the cross section of the concavo-convex base (3-D) was observed with a transmission electron microscope H-7500 (manufactured by Hitachi, Ltd.), an aluminum layer was formed on both the convex and concave portions of the concavo-convex surface of the concavo-convex base (3-D). It was confirmed that the structure can function as a grid polarizing film.

(3-3: Formation of Protective Layer—Production of Optical Member (3-E))
Hexafunctional urethane acrylate oligomer (manufactured by Shin-Nakamura Chemical Co., Ltd., NK Oligo U-6HA) 3 parts by weight, photopolymerization initiator (2,2-dimethoxy-1,2-diphenylethane-1-one) 0.5 part by weight, and Mixing 296.5 parts by weight of methyl ethyl ketone, a silica sol slurry of methyl ethyl ketone (manufactured by Nissan Chemical Industries, MEK-ST, solid content concentration: 30% by weight, average particle diameter (measured by nitrogen adsorption method): 14 nm) 0.7 part by weight After adding, a coating solution was prepared by mixing with a homogenizer.
Next, using the remote atmospheric pressure plasma processing apparatus (manufactured by E-Square Co., Ltd.), the uneven substrate (3-D) produced in (3-2) is output 0.8 kW, nitrogen flow rate 200 L / min. The surface treatment is carried out under the condition of a conveyance speed of 1 m / min, after being immersed in the coating solution for 30 seconds, dried for 1 minute with a dryer at 80 ° C., and irradiated with ultraviolet rays having an output of 300 mW / cm ² for 5 seconds. As a result, an optical member (3-E) was obtained.

(3-4: Evaluation of optical member (3-E))
As a result of measuring the optical characteristics of the produced optical member (3-E) in the same manner as in (2-4) of Example 2, the polarization transmittance was 82% and the polarization reflectance was 83%.
Moreover, the observation cross section for TEM of the produced optical member (3-E) was produced using the micro sampling apparatus of the focused ion beam processing observation apparatus FB-2100 (made by Hitachi, Ltd.). As a result of measuring the thickness of the coating layer by observing the cross section using a transmission electron microscope H-7500 (manufactured by Hitachi, Ltd.), the thickness was 13 nm.
As a result of conducting the scratch resistance test of the optical member (3-E), the change of the concavo-convex structure was “good”. Furthermore, as a result of measuring the optical characteristics of the optical member (3-E) after the scratch resistance test in the same manner as (2-4) of Example 2, the polarization transmittance after the scratch resistance test was 82%, and the polarization reflectance. Was 82%, and no change was observed in the optical characteristics.

<Example 4>
In a 2000 ml four-necked flask equipped with a thermometer, a stirrer, a nitrogen inlet tube and a condenser tube, 840 parts by weight of Exenol 2020 (trade name, manufactured by Asahi Glass Co., Ltd., hydroxyl value 56 mgKOH / g), a tolylene diisocyanate 119 Part by weight and 200 parts by weight of methyl ethyl ketone were added and reacted at 75 ° C. for 1 hour while introducing nitrogen. After completion of the reaction, the mixture is cooled to 60 ° C., 35.6 parts by weight of dimethylolpropionic acid is added and reacted at 75 ° C., and a urethane resin solution in which the proportion of terminal-NCO accounts for 0.5% of all terminals is obtained. A prepolymer was obtained.
Next, the prepolymer was cooled to 40 ° C., and 1500 parts by weight of water, 3.3 parts by weight of monoethanolamine (boiling point: 171 ° C.) and 21.3 parts by weight of triethylamine (boiling point: 89 ° C.) were added. Emulsification was performed by stirring at high speed. Methyl ethyl ketone was distilled off from the emulsion under heating and reduced pressure to obtain an aqueous urethane resin solution having a solid content of 40%. Next, after adding 0.1 parts by weight of carbodiimide compound Carbodilite V-02 (manufactured by Nisshinbo) and 97.4 parts by weight of water to 2.5 parts by weight of the prepared aqueous urethane resin solution, the silica sol slurry (Nissan) Made by Kagaku Kogyo Co., Ltd., Snowtex ZL, solid content concentration: 40% by weight, average particle diameter (measured by nitrogen adsorption method): 98 nm) 0.25 parts by weight was added, and the mixture was prepared with a homogenizer to prepare a coating solution. .
Next, using the corona treatment device (manufactured by Kasuga Denki), the uneven substrate (3-D) produced in (3-2) of Example 3 was used, an output of 30 W, a wire electrode having a diameter of 1.2 mm, and an electrode length of 240 mm. The optical member is subjected to a discharge treatment once under the conditions of 1.0 mm between work electrodes and 1 m / min of conveying speed, immersed in the coating solution for 30 seconds, and then dried for 10 minutes with a 120 ° C. dryer. 4 was obtained. The observation cross section for TEM of the produced optical member 4 was produced using the microsampling apparatus of the focused ion beam processing observation apparatus FB-2100 (manufactured by Hitachi, Ltd.). As a result of measuring the thickness of the coating layer by observing the cross section using a transmission electron microscope H-7500 (manufactured by Hitachi, Ltd.), the thickness was 13 nm.
As a result of conducting the scratch resistance test of the optical member 4, the change of the concavo-convex structure was “good”. Furthermore, the optical characteristics of the optical member 4 before and after the scratch resistance test were measured in the same manner as in Example 2 (2-4). As a result, the polarization transmittance before the scratch resistance test was 82% and the polarization reflectance was 82%. On the other hand, the polarized light transmittance after the scratch resistance test was 81% and the polarized light reflectance was 81%, and almost no change was observed in the optical characteristics.

<Example 5>
In the preparation of the coating liquid of Example 4, instead of the silica sol slurry, an alumina sol (manufactured by Nissan Chemical Industries, alumina sol 520, solid content concentration: 20% by weight, average particle size (measured by nitrogen adsorption method): 18 nm) 0.25 A weight part was added, and the surface treatment of the concavo-convex base material of Example 4 was performed by using a via discharge excimer lamp (manufactured by USHIO INC.) With a light of 254 nm (4.9 eV) in nitrogen at an irradiation distance of 1 mm and an irradiation time of 360 seconds. An optical member was manufactured by the same operation as in Example 4 except that the surface treatment was performed under the conditions described above to obtain an optical member 5. The observation cross section for TEM of the produced optical member 5 was produced using the micro sampling apparatus of the focused ion beam processing observation apparatus FB-2100 (made by Hitachi, Ltd.). As a result of observing the cross section using a transmission electron microscope H-7500 (manufactured by Hitachi, Ltd.) and measuring the thickness of the coating layer, the thickness was 14 nm.
As a result of conducting the scratch resistance test of the optical member 5, the change of the concavo-convex structure was “good”. Furthermore, the optical characteristics of the optical member 5 before and after the scratch resistance test were measured in the same manner as in Example 2 (2-4). As a result, the polarization transmittance before the scratch resistance test was 82% and the polarization reflectance was 82%. On the other hand, the polarized light transmittance after the scratch resistance test was 82% and the polarized light reflectance was 81%, and almost no change was observed in the optical characteristics.

<Comparative Example 1>
In the preparation of the coating liquid, an optical member was produced by the same operation as in Example 1 except that the silica sol slurry was not added, thereby obtaining an optical member C1.
As a result of measuring the thickness of the protective layer of the optical member C1 in the same manner as (1-3) of Example 1, the thickness of the protective layer was 40 nm.
As a result of performing the scratch resistance test of the optical member C1, the change of the concavo-convex structure was “impossible”. Further, the reflectance of the optical member C1 after the scratch resistance test was measured in the same manner as in Example 1-3 (1-3). As a result, the reflectance after the scratch resistance test was 3.6%, and the optical characteristics greatly changed. It was observed.

<Comparative example 2>
In the preparation of the coating liquid, an optical member was produced by the same operation as in Example 3 except that the silica sol slurry was not added, thereby obtaining an optical member C2.
As a result of measuring the thickness of the protective layer of the optical member C2 in the same manner as in (2-4) of Example 2, the thickness of the protective layer was 12 nm.
As a result of conducting the scratch resistance test of the optical member C2, the change of the concavo-convex structure was “OK”. Furthermore, the reflectance of the optical member C2 before and after the scratch resistance test was measured in the same manner as in Example 2 (2-4). As a result, the polarization transmittance before the scratch resistance test was 82% and the polarization reflectance was 83%. On the other hand, the polarized light transmittance after the scratch resistance test was 83% and the polarized light reflectance was 36%, and the polarization reflectance was greatly reduced.

<Comparative Example 3>
In the adjustment of the coating liquid in (3-3), an optical member was produced in the same manner as in Example 3 except that the blending ratio of methyl ethyl ketone was 96.5 parts by weight, and the optical member C3 was obtained.
As a result of measuring the thickness of the protective layer of the optical member C3 in the same manner as in (2-4) of Example 2, the thickness of the protective layer was 25 nm. As a result of conducting the scratch resistance test of the optical member C3, the change of the concavo-convex structure was “OK”. Furthermore, the optical characteristics of the optical member C3 before and after the scratch resistance test were measured in the same manner as in Example 2 (2-4). As a result, the polarization transmittance before the scratch resistance test was 82% and the polarization reflectance was 83%. On the other hand, the polarized light transmittance after the scratch resistance test was 82% and the polarized light reflectance was 42%, and the polarization reflectance was greatly reduced.

310 Uneven substrate 310P Convex 311A, 311B, 311B2 Metal layer 420 Protective layer

Claims (6)

An uneven member having a concavo-convex surface having a concavo-convex structure with a period of 900 nm or less on at least a part of the surface, and an optical member having a protective layer provided on the concavo-convex surface,
The optical member, wherein the protective layer contains an organic material and inorganic fine particles having an average particle diameter of 100 nm or less.   The optical member according to claim 1, wherein the protective layer has a thickness of 50 nm or less.   The optical member according to claim 1, wherein the concavo-convex structure is a hook-like structure extending in parallel.   The optical member according to claim 3, wherein the concavo-convex substrate has a transparent resin layer and a metal layer extending along the ridge.   The optical member according to claim 1, wherein the organic material of the protective layer is selected from the group consisting of a thermosetting resin, an energy ray curable resin, and a mixture thereof.   A grid polarizing film comprising the optical member according to claim 1.

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