WO2006035649A1 - Process for producing surface-roughened sheet, surface-roughened sheet, and antiglare sheet - Google Patents

Abstract

A process by which a surface-roughened sheet having a finely roughened surface structure and useful as an antiglare sheet can be easily produced without using fine inorganic or organic particles. The process for surface-roughened sheet production is characterized by comprising: a first step in which an organic resin material is mixed with a material incompatible with the organic resin material to prepare a coating fluid; a second step in which the coating fluid is applied to form a coating film having a phase separation structure in which the phase of the organic resin material has been separated from the phase of the incompatible material; and a third step in which the coating film is subjected to a curing treatment to cure the organic resin material and thereby fix the phase separation structure and then the incompatible material is removed from the cured coating film to form a cured resin layer having a surface-roughened structure.

Description

 Specification

 Manufacturing method of surface uneven sheet, surface uneven sheet and antiglare sheet Technical Field

 [0001] The present invention relates to an antiglare sheet or the like for suppressing a reduction in visibility of a screen of a display device such as a liquid crystal display (LCD), a flat panel display (FPD), an organic EL, and a PDP. The present invention relates to a method for producing a surface uneven sheet having a fine surface uneven structure that can be used.

 Background art

 Conventionally, a display device such as a liquid crystal display (LCD), when light from an external bright light source is incident on the surface of the display device, is reflected by reflection of the light source or shadow of a person or the like. The visibility of the screen is significantly hindered.

 Therefore, on the surface of the display device, for the purpose of improving the visibility of the screen, the reflected light of the display device surface is diffused, and regular reflection of the incident light is suppressed to prevent the reflection (anti-glare property). An antiglare layer having a fine surface uneven structure is formed.

 [0003] As a method for forming such an antiglare layer having a fine surface concavo-convex structure on the display device surface, formation of the antiglare layer on the display device surface is easy if the surface concavo-convex structure is easy to be miniaturized. For this reason, a method in which fine particles are dispersed in a cured resin is applied to the surface of a display device and the resin is cured (for example, Patent Document 1).

 This method includes, for example, inorganic fine particles (for example, calcium carbonate particles, titanium oxide particles, silica particles) and organic fine particles (acrylic polymer particles, silicone polymer particles) in a curable resin such as an ultraviolet curable resin. Etc.) is applied to the surface of the display device and cured to form an antiglare layer having a fine surface uneven structure on the display device surface.

 However, in a display device having an antiglare layer formed by the above method, the antiglare layer has sufficient antiglare properties due to poor dispersion of the fine particles in the curable resin. There are cases where problems such as poor strength, poor transparency of the antiglare layer, and poor appearance occur.

Furthermore, as time passes, the fine particles are dispersed in the cured resin to float on the surface of the antiglare layer. The anti-glare performance of the anti-glare layer formed on the surface of the display device is reduced, or the fine particles floating on the surface itself cause poor appearance (for example, dirt on the surface). There is also.

 [0005] In addition, a method of forming an antiglare film having a fine surface concavo-convex structure to be used by being laminated on the surface of a display device by using a transfer method has also been proposed (for example, Patent Document 2). In this method, a moldable film having a concavo-convex shape formed on the surface, a cured resin is poured into the moldable film, the cured resin is cured, and the concavo-convex shape is cured. Thus, an antiglare film is formed.

 However, the cured resin adheres to the shaped film, so that the uneven shape cannot be copied and the desired anti-glare property cannot be obtained, or the shaped film is used many times. As a result, the surface irregularity shape of the shaped film changes, and the workability is complicated.

[0006] Therefore, there is a demand for a method capable of easily producing a surface uneven sheet having a fine surface uneven structure useful as an antiglare sheet without using inorganic or organic fine particles. Patent Document 1: Japanese Patent Application Laid-Open No. 9-127312

 Patent Document 2: International Publication No. 95Z31737 Pamphlet

 Disclosure of the invention

 Problems to be solved by the invention

[0007] In view of the above problems, the present invention provides a method by which a surface uneven sheet having a fine surface uneven structure useful as an antiglare sheet without using inorganic or organic fine particles can be easily produced. Is an issue.

 Means for solving the problem

 [0008] As a result of intensive studies to solve the above problems, the present inventors applied a coating liquid obtained by mixing an organic resin material and a material incompatible with the organic resin material. Then, after forming a coating film having a phase separation structure, curing the coating film, and removing the incompatible material from the cured coating film by a predetermined method, the surface having a fine surface uneven structure The inventors have found that a concavo-convex sheet can be produced, and have completed the present invention.

That is, the present invention mixes an organic resin material and a material that is incompatible with the organic resin material. A first step of preparing a coating solution, and applying the coating solution to form a coating film having a phase separation structure in which the organic resin material and the incompatible material are phase separated. A second step, the coating film is cured, the organic resin material is cured and the phase separation structure is fixed, and then the incompatible coating is applied from the coated film. And a third step of forming a cured resin layer having a surface-concave / convex structure by removing the material.

 In the manufacturing method, a coating liquid containing an organic resin material and a material incompatible with the organic resin material is applied to form a coating film having a phase separation structure, and cured. By removing the incompatible material from the hardened coating film, a fine surface uneven structure can be formed in the cured resin layer.

 [0010] In addition, the present invention provides a first step of preparing a coating liquid by mixing an organic resin material, a material incompatible with the organic resin material, and a solvent, and applying the coating liquid A second step of forming a coating film having a phase-separated structure in which the organic resin material and the incompatible material are phase-separated, and a solvent for removing the solvent from the coating film after the second step. The coating film from which the solvent has been removed by the removal step and the solvent removal step is cured, the organic resin material is cured to fix the phase separation structure, and then the curing process is performed. And a third step of forming a cured resin layer having a surface uneven structure by removing the incompatible material from the inside, and providing a method for producing a surface uneven sheet.

 A coating film having a phase separation structure by applying a coating liquid containing an organic resin material, a material incompatible with the organic resin material, and a solvent in the manufacturing method, and removing the solvent. By forming the film, curing, and removing the incompatible material from the cured coating film, a fine surface uneven structure can be formed in the cured resin layer.

 [0011] In the present invention, it is preferable to remove the incompatible material in the third step by solvent extraction.

 [0012] Furthermore, in the present invention, the solvent used for solvent extraction is preferably liquefied carbon dioxide or carbon dioxide in a supercritical state.

In the present invention, the solvent used for solvent extraction is preferably an organic solvent that selectively dissolves incompatible materials. The invention's effect

 [0014] In the method for producing a surface uneven sheet according to the present invention, inorganic or organic fine particles are not used. Etc. can be prevented, and workability is also good.

 Further, in the method for producing a surface uneven sheet according to the present invention, since fine particles such as inorganic or organic fine particles are not used, it is easy to design characteristics such as anti-glare performance without scattering caused by the fine particles.

 BEST MODE FOR CARRYING OUT THE INVENTION

[0015] Hereinafter, a method for producing a surface uneven sheet according to the present invention will be described.

 The method for producing an uneven surface sheet according to the present invention includes a first step of mixing an organic resin material and a material incompatible with the organic resin material to prepare a coating solution, and applying the coating solution. A second step of forming a coating film having a phase-separated structure in which the organic resin material and the incompatible material are phase-separated; and curing the coating film to cure the organic resin material. A third step of fixing the phase separation structure and then removing the incompatible material from the cured coating film to form a cured resin layer having an uneven surface structure. Yes.

 First, in the present invention, an organic resin material and a material that is incompatible with the organic resin material are mixed in the coating liquid prepared in the first step.

 As the organic resin material, when the organic resin material is cured, a material having sufficient strength and transparency as a film can be used without particular limitation.

 Examples of the organic resin material include a thermosetting resin, an ultraviolet curable resin, an electron beam curable resin, a two-component mixed resin, and preferably a thermosetting resin and an ultraviolet hard resin. Chemicalized rosin.

 In particular, the ultraviolet curable resin is preferable in that it can be cured by ultraviolet irradiation and can be easily operated and can efficiently form a cured resin layer.

[0017] Examples of the thermosetting resin include epoxy resins, acrylic resins, unsaturated polyester resins, phenol resins, melamine resins, urea resins, urethane resins, and silicone resins. . [0018] Examples of the ultraviolet curable resin include various types such as polyester, acrylic, urethane, amide, silicone, and epoxy. The ultraviolet curable resin includes ultraviolet curable monomers, oligomers, polymers, and the like. These have functional groups that can be polymerized by irradiation with ultraviolet rays, and preferably include two or more of the functional groups in one molecule, particularly 3 to 6 functional groups in one molecule. Monomers and oligomers of the system are preferred.

 [0019] In the present invention, the material incompatible with the organic resin material is not compatible with the organic resin material, and even if mixed and stirred, the time passes. It has a mixing ratio region that causes phase separation.

 Such an incompatible material may be any material that can be removed by a method such as solvent extraction after phase separation and fixing of the phase separation structure when mixed with the organic resin material. As the incompatible material, either an inorganic material or an organic material can be used, but an organic material is preferable.

 [0020] The incompatible material is appropriately selected according to the organic resin material to be used. For example, polyalkylene glycol such as polyethylene glycol and polypropylene glycol, and one end of the polyalkylene glycol. Alternatively, both ends of the methyl blockade, one or both ends of the polyalkylene glycol (meth) acrylate block, urethane prepolymer, phenoxypolyethylene glycol (meth) acrylate, ε single-prolatathone (meth) acrylate , Trimethylolpropane tri (meth) acrylate, dipentaerythritol hexane (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, oligoester (meth) acrylate, alkyl (meth) acrylate , End is (meth) atarire Examples include compounds sealed with a sheet.

 It is also possible to use a compound in which the end is blocked with (meth) acrylate and the end is blocked with a methyl group or a carboxyl group.

 These can be used alone or in combination of two or more.

[0021] The molecular weight of the incompatible material is not particularly limited, but is preferably 10,000 or less (for example, 100 to 10,000) as the weight average molecular weight because the subsequent removal operation becomes easy. Is about 200-3,000. The weight average molecular weight is measured by the method described in the examples.

 [0022] As a preferable combination of the organic resin material and the incompatible material, an at least UV-curable resin (particularly, one having two or more polymerizable functional groups) and an alkyl ( A combination with (meth) acrylate can be mentioned.

 Specifically, examples of the organic resin material include urethane acrylic ultraviolet curable resin, poly (meth) acrylate of polyvalent alcohol such as pentaerythritol triacrylate and dipentaerythritol hexatalate, and tris ( A combination of one or two or more of 2-hydroxyethyl) isocyanate triatalylate and an incompatible material with an alkyl (meth) acrylate.

[0023] The mixing amount of the organic resin material and the incompatible material is 10 to 400 parts by weight of the incompatible material with respect to 100 parts by weight of the organic resin material. 20-200 parts by weight of compatible material.

 By mixing incompatible materials in the range of 10 to 400 parts by weight with 100 parts by weight of the organic resin material, the haze value, average peak-to-valley spacing (Sm), and centerline average of the surface uneven sheet formed The surface roughness (Ra) can be easily adjusted to a desired range.

 If the mixing amount of incompatible materials exceeds 400 parts by weight, the phase separation structure will be too large, and the average peak-to-valley spacing (Sm) and centerline average surface roughness (Ra) will become too large. Have a problem.

 In addition, when the amount of the incompatible material is less than 10 parts by weight, the phase separation structure becomes too fine and the desired average crest / valley spacing (Sm) and centerline average surface roughness (Ra) are obtained. It has problems such as difficulty.

 In mixing the organic resin material and the incompatible material, an organic solvent can be further mixed. By mixing the organic solvent, the viscosity of the coating solution can be lowered, coating becomes easy, and coating unevenness occurs.

 The organic solvent may be an organic resin that does not dissolve at least one of the organic resin material and the incompatible material, or may dissolve both. It is suitably selected according to the material and the incompatible material.

Even if the organic solvent dissolves both, the organic solvent can be removed by removing the organic solvent. The fat material and the incompatible material are phase-separated.

 Examples of the organic solvent include aromatic hydrocarbons such as xylene and toluene, alcohols such as methanol, ethanol and isopropyl alcohol, ketones such as methyl ethyl ketone, and esters such as methyl acetate and ethyl acetate. Can be mentioned.

 As the organic solvent, xylene, toluene, ethyl acetate and the like are preferable.

 [0025] The mixing amount of the organic solvent is appropriately determined depending on the liquid viscosity of the mixture of the organic resin material and the incompatible material, but is usually 10 to 100 parts by weight of the organic resin material. 500 parts by weight, preferably 10 to 300 parts by weight, more preferably 30 to 200 parts by weight.

 When the amount of the organic solvent mixed exceeds 500 parts by weight, the viscosity of the coating solution becomes low, so that the coating film becomes too thin and the resulting sheet becomes extremely thin.

 Further, when the amount of the organic solvent mixed is less than 10 parts by weight, there is a problem that the viscosity of the coating liquid becomes high and coating unevenness is likely to occur.

[0026] Further, the coating liquid may be mixed with a polymerization initiator for curing the organic resin material. A well-known thing can be used as said polymerization initiator.

 Specific examples of the polymerization initiator used in the thermosetting resin include organic peroxides such as dibenzoyl peroxide, di-tert-butyl peroxide, tamen hydroperoxide, lauroyl peroxide, and the like. Examples include azo compounds such as 2,1 azobisisobutyryl-tolyl and 2,2,1 azobisisovalero-tolyl.

 Specific examples of the polymerization initiator used in the ultraviolet curable resin include, for example, acetophenones, benzophenones, diacetyls, benzyls, benzoins, benzoin ethers, benzyl dimethyl ketals, benzoyl benzoates. And compounds such as hydroxyphenyl ketones.

 The mixing amount of the polymerization initiator is 0.01 to 10 parts by weight of the polymerization initiator with respect to 100 parts by weight of the organic resin material, and preferably 0.05 to 10 parts by weight of the polymerization initiator. is there.

[0027] Further, the coating liquid includes a leveling agent, a tita soot pea agent, an antistatic agent, an antioxidant, an ultraviolet absorber, a light stabilizer, a filler, and the like so long as the object of the present invention is not impaired. A colorant or the like may be mixed. These may be used alone or in combination.

 [0028] Further, the coating liquid may be mixed with a crosslinking agent that promotes crosslinking of the organic resin material when the organic resin material is cured, if necessary.

 Preferred types of crosslinking agents include, for example, polyisocyanates such as diphenylmethane diisocyanate and tolylene diisocyanate, polyepoxy, various metal salts, chelate compounds and the like.

 The amount of the crosslinking agent to be mixed is not particularly limited as long as it does not impair the object of the present invention, but is preferably 20 parts by weight or less with respect to 100 parts by weight of the organic resin material, and appropriately within this range. Can be prepared. These cross-linking agents can be used alone or in combination of two or more without any problem.

 Moreover, you may add a chain transfer agent and a plasticizer as needed.

[0029] In the present invention, the substrate to which the coating liquid is applied may be transparent (transparent substrate) or opaque (opaque substrate) as long as it has a smooth surface! / ヽ. Examples of the transparent substrate include glass and various transparent plastic material films. Moreover, as an opaque base material, metal plates, such as stainless steel, etc. can be mentioned. As the base material, the transparent base material is preferable.

[0030] When the substrate is a transparent plastic material film, examples of the film include polyester polymers such as polyethylene terephthalate and polyethylene naphthalate, and senorelose systems such as dicetinoresenorelose and triacetinoselenose. Mention may be made of acrylic polymer films such as polymers, polycarbonate polymers, and polymethylmethacrylate.

 Also, styrene polymers such as polystyrene and acrylonitrile styrene copolymers, polyethylene, polypropylene, polyolefins having a cyclic or norbornene structure, olefin polymers such as ethylene propylene copolymers, butyl chloride polymers, and Nai Nya. Examples also include amide polymer films such as aromatic polyamides.

In addition, imide polymers, snolephone polymers, polyetheretherolephone polymers, polyetheretherketone polymers, polyphenylene sulfide polymers, vinylenoleolol polymers, vinylidene chloride polymers, bull petitar polymers, arylenes. And polymer films such as polymer polymers, polyoxymethylene polymers, epoxy polymers and blends of the aforementioned polymers.

 In the present invention, one kind of the film may be used as a single layer, or two or more of the same kind or different kinds of films may be laminated.

 The film should be as colorless and transparent as possible. The transmittance in the wavelength region of 400 to 800 nm is preferably 80% or more, and the transmittance is more preferably 90% or more.

[0031] The transparent plastic material film may be stretched, in which case it may be uniaxially stretched, biaxially stretched, or Z-axis stretched. .

 The stretching means and the stretching ratio are not particularly limited, but it is preferable to make the same magnification in both the width direction (MD direction) and the longitudinal direction (TD direction).

 The draw ratio is 0.5 to 3 times, preferably 1 to 2 times.

 In general, plastic material films exhibit birefringence when subjected to stretching treatment. Therefore, when used as an optical application, the plastic material film has a non-stretched state that does not disturb the polarization state of the liquid crystal cell that has already been set. I prefer to use film.

[0032] When the base material is the transparent plastic material film, at least one surface may be subjected to various surface treatments such as corona treatment, UV treatment, and EB (electron beam) treatment.

 By performing the surface treatment on the surface of the film, the adhesion between the cured resin layer obtained by applying and curing the coating liquid and the film can be improved.

[0033] The thickness of the base material is appropriately set according to the purpose, but is generally 10 to 500 µm from the viewpoints of workability such as strength, handleability, and thin film properties. Is 20 to 300 m, more preferably 30 to 200 μm.

[0034] Next, a method for producing a surface uneven sheet according to the present invention will be described along each step.

 First, in the first step, an organic resin material and a material that is incompatible with the organic resin material are mixed in a solvent-free manner, or incompatible with the organic resin material and the organic resin material. These materials and the like are mixed using an organic solvent to prepare a coating solution.

It is preferable that the coating solution thus obtained is slightly cloudy visually. Yes.

 As a mixing method for preparing the coating liquid, it is not necessary to adopt any special method. For example, a general mixing method such as stirring and ultrasonic irradiation can be used.

 The prepared coating solution has a turbidity after mixing and thorough stirring, and the liquid turbidity is slightly clouded visually.

[0035] Next, in the second step, the coating liquid obtained as described above is applied to, for example, the substrate to form a coating film having a phase separation structure.

[0036] As a method for forming a coating film on the substrate, for example, an appropriate method such as phanten, phanten metalling, die coater, casting, spin coating, or gravure method can be used.

 In the case where the coating liquid contains an organic solvent, after forming a coating film on the substrate using the above method, the organic solvent is generally removed by heating, reduced pressure removal, etc. in the solvent removal step. It is done and removed using methods.

[0037] Next, in the third step, the coating film is subjected to a curing process, the organic resin material is cured to fix the phase separation structure, and then the coating film is subjected to the curing process. The incompatible material is removed, and a cured resin layer having an uneven surface structure is formed on the substrate.

[0038] Before the curing treatment, the organic resin material and the incompatible material are in a liquid and phase-separated state. However, by performing the curing treatment, phase separation is promoted and the organic resin material is separated. It separates into a hardened resin layer of the fat material and a liquid layer of the incompatible material, and an uneven structure is formed at the interface portion.

 In the first step, the concavo-convex structure is formed at a level where the turbidity after the organic resin material and the incompatible material are mixed and sufficiently stirred is slightly clouded visually. If there is, it is achieved.

 For the curing treatment, a curing treatment method corresponding to the curable resin material used as the organic resin material is appropriately employed.

That is, when the organic resin material is an ultraviolet curable resin, the organic resin material may be cured by irradiating the coating film with ultraviolet rays. What is necessary is just to heat and harden | cure when it is a rosin.

 The resin obtained by curing the organic resin material is as colorless and transparent as possible, and the transmittance in the wavelength region of 400 to 800 nm is preferably 80% or more, and the transmittance is preferably 90% or more. Is more preferable.

[0040] The method for removing the incompatible material from the cured coating film can be performed by extraction with a solvent.

 By removing the incompatible material from the cured coating film, the portion of the phase separation structure in the coating film occupied by the incompatible material is removed, and the surface uneven structure is removed. A cured rosin layer is formed.

[0041] The extraction solvent for removing the incompatible material from the cured coating film is a good solvent for the incompatible material used in the present invention, and is included in the present invention. It is not particularly limited as long as it does not dissolve the cured product of the organic resin material to be used. If it has such properties, it is appropriately selected from general solvents and used. Although not particularly limited, liquid carbon dioxide or carbon dioxide in a supercritical state (supercritical carbon dioxide) is used from the viewpoint of removal efficiency and harmlessness.

[0042] An apparatus for removing incompatible materials in the cured coating film with liquefied carbon dioxide or carbon dioxide in a supercritical state (supercritical carbon dioxide) may be a pressure vessel. There is no particular limitation as long as the pressure vessel is a batch type pressure vessel or a pressure vessel equipped with a sheet feeding and winding device.

[0043] A specific method in the case of using liquid carboxylic acid carbon or supercritical diacid carbon (supercritical diacid carbon) as an extraction solvent will be described.

 The cured coating film is placed in a pressure vessel, carbon dioxide is injected, and liquefied carbon dioxide or supercritical carbon dioxide is allowed to permeate the coating film.

After sufficiently infiltrating the carbon dioxide, the exhaust and injection of carbon dioxide are repeated continuously or intermittently to remove the incompatible material in the cured coating film from The incompatible material is removed from the coating film by extraction (dissolution) into carbonized carbon or supercritical diacid carbon (supercritical diacid carbon). [0044] As the extraction (dissolution) conditions, for example, in the case of extracting and removing an incompatible material with carbon dioxide in a supercritical state (supercritical carbon dioxide), the temperature is 32 ° C and the pressure is 7.3 MPa or more. In the supercritical state, the coating internal force incompatible material can be efficiently removed by promoting the swelling of the cured organic resin material and improving the diffusion coefficient of the incompatible material.

 In the case of using liquefied carbon dioxide, the diffusion coefficient is lowered, but the permeability to the cured organic resin material is improved. This material can be removed efficiently.

[0045] In extracting (dissolving) the incompatible material from the coating film subjected to the curing treatment, an organic solvent that does not dissolve the cured product of the organic resin material but dissolves the incompatible material It is possible to use

 By using the organic solvent, the incompatible material can be removed under atmospheric pressure, and deformation of the substrate can be suppressed as compared with the case where the organic solvent is removed under pressure.

 Moreover, extraction time can also be shortened by selecting an organic solvent.

 Furthermore, the process of removing the said incompatible material from the said coating film can also be continuously performed by letting the coating film which performed the said hardening process sequentially in an organic solvent.

[0046] Examples of the organic solvent include those commonly used, such as toluene, ethanol, ethyl acetate, heptane, and the like.

 These organic solvents may be used alone or in admixture of two or more, but are preferably extracted with toluene or ethanol from the viewpoint of removal efficiency of incompatible materials.

[0047] The method for removing the incompatible material using the organic solvent is not particularly limited. For example, a method of removing the incompatible material by impregnating the cured coating film with an organic solvent. Or a method of removing the incompatible material by coating the organic solvent with the coating film subjected to the curing treatment using a spray nozzle or the like.

 The viewpoint of efficient removal is preferably a method in which an insoluble material is removed by impregnating the cured coating film with an organic solvent.

For example, the incompatible material is removed by immersing in a 200 ml organic solvent for 10 minutes to a cured film (length 10 cm x width 15 cm x thickness 4 m) at a temperature of 25 ° C. It can be done.

 Further, the incompatible material can be efficiently removed by performing extraction while changing the organic solvent several times or by stirring the organic solvent.

 [0048] The surface uneven structure of the surface uneven sheet in the present invention can be appropriately prepared depending on the combination or blending amount of an incompatible material and an organic resin material.

 By preparing a combination or blending amount of an incompatible material and an organic resin material, the haze value of the surface uneven sheet can be made desired as an antiglare sheet.

 [0049] The average crest / valley spacing (Sm) of the surface uneven sheet produced by the production method of the present invention is 80 to 400 µm, preferably 80 to 300 µm.

 If the average peak-to-valley spacing (Sm) is less than 80 m, the optical characteristics may be almost the same as when there is no unevenness.

 In addition, when the average peak-to-valley spacing (Sm) force exceeds OO / z m, there is a problem that the roughness becomes larger.

 Note that the average peak-valley interval (Sm) is measured by the method described in the examples.

[0050] The center line average surface roughness (Ra) of the surface uneven sheet produced by the production method of the present invention is 50 to 1500, preferably 50 to LOOOnm.

 When the center line average surface roughness (Ra) is within the above range, the antiglare property functions sufficiently.

 The centerline average surface roughness (Ra) is measured by the method described in the examples.

[0051] By setting the average crest / valley spacing (Sm) of the surface uneven sheet manufactured by the manufacturing method of the present invention to 80 to 400 μm and the centerline average surface roughness (Ra) of 50 to 1500 nm, The haze value can be controlled within a range of 5 to 50%, and antiglare properties can be exhibited.

 The haze value is preferably 50% or less, and more preferably 40% or less from the viewpoint of image clarity.

 The haze value is measured by the method described in the examples.

[0052] The thickness of the surface uneven sheet is not particularly limited, but is 0.5 to 30 µm, preferably 3 to 20 m. When the thickness of the surface uneven sheet is within the above range, the handling property is good. In addition, the thickness of the surface uneven | corrugated sheet does not include the thickness of the film used as a base material.

 [0053] A low refractive index layer having an antireflection function can be separately provided on the surface having the concavo-convex structure of the surface concavo-convex sheet. The material of the low refractive index layer is not particularly limited as long as it has a lower refractive index than the material constituting the cured resin layer. Examples of the method for forming the low refractive index layer include a wet coating method and a vacuum deposition method.

 [0054] When the surface uneven sheet produced by the production method of the present invention is formed on at least one side of a transparent substrate, it can be used as an antiglare sheet. Various optical elements can be attached to the other surface of the transparent substrate of the antiglare sheet.

 As the transparent substrate, the transparent plastic material film described above can be used as appropriate.

 Examples of the optical element include a polarizing plate. The polarizing plate is not particularly limited, and various types can be used.

 [0055] Further, a polarizing plate or the like with an antiglare sheet attached thereto, and a viewing angle so that the image can be seen clearly even when the screen of the liquid crystal display device is viewed from a slightly oblique direction rather than perpendicular to the screen. It may be combined with a viewing angle compensation phase difference plate for widening the brightness, or a brightness enhancement film for improving the brightness.

 [0056] When the optical element is attached to the antiglare sheet, an adhesive or a pressure-sensitive adhesive can be used. The type of adhesive or pressure-sensitive adhesive is not particularly limited, and various types can be used. In particular, an acrylic pressure-sensitive adhesive that exhibits adhesive properties such as optical transparency, appropriate wettability, and cohesiveness, and is excellent in weather resistance, heat resistance, and the like is preferably used.

 Example

 Hereinafter, the ability to specifically explain the present invention by way of examples The present invention is not limited in any way by these examples.

 [0058] (Method of measuring weight average molecular weight)

 The weight average molecular weight is a value converted by standard polystyrene by the GPC method.

Model name of Tosoh Corporation as GPC main unit: “HLC-8120GPCJ is used, column The temperature was 40 ° C, the pump flow rate was 0.5 mlZmin, and the detector RI was used. Standard polystyrene calibration curves with known molecular weights (molecular weights of 20.6 million, 8.42 million, 4.48 million, 1.11 million, 77,000, 354,000, 189,000, 98,000, 372,000, 171,000, The molecular weight was determined from the converted molecular weight using 9830, 5870, 2500, 1050 and 500 standard polystyrene).

 Column used: Trade name “TSKgel GMH—H (S)” x 2 (Tosoichi Co., Ltd.) Mobile phase: Tetrahydrofuran

 Injection volume: 100 1

 Sample concentration: 1. OgZK tetrahydrofuran solution)

[0059] (Measurement method of total light transmittance)

 Using Suga Test Instruments Co., Ltd .: Haze meter, model name: HGM-2DP, all light rays are measured when light rays (400 nm to 700 nm) are transmitted from the surface uneven surface side of the surface uneven surface sheet. did.

 For the total light transmittance (Tt), the ratio of the incident light quantity (T1) and the total light quantity (T2) that passed through the test piece was obtained by the following formula. (Formula): Tt = T2ZTl (%)

 The measured values in Table 2 are measured values at 550 nm.

[0060] (Measuring method of mean interval between valleys (Sm))

 The surface roughness structure of the surface roughness sheet conforms to JIS B 0601 (1994) with a measurement length of 8 mm, and a stylus type surface roughness measuring instrument (manufactured by Kosaka Laboratory, model name: High-precision fine shape measuring instrument Surf Measurement was performed using a coder ET4000) at a stylus speed of 500 mZs.

[0061] (Measuring method of centerline average surface roughness (Ra))

 The surface roughness structure of the surface roughness sheet conforms to JIS B 0601 (1994) with a measurement length of 8 mm, and a stylus type surface roughness measuring instrument (manufactured by Kosaka Laboratory, model name: High-precision fine shape measuring instrument Surf Using a coder ET4000), the measurement was performed in the same manner as the method for measuring the average peak-to-valley spacing (Sm).

[0062] (Method of measuring haze value)

In accordance with JIS K 7105-1981, use “Suga Test Instruments Co., Ltd. Model name: Digital Glossmeter U GV-5DP” so that the surface of the surface uneven structure of the surface uneven sheet faces the light source. 7 measured. [0063] (Glossiness measurement method)

 The 60 ° gloss was measured according to JIS K 7105-1981 using “Suga Test Instruments Co., Ltd., model name: Digital Deflection Glossmeter UGV-5DP”.

[0064] (Total reflectance measurement method)

 A black acrylic plate was attached to the base material surface where the surface unevenness structure of the surface unevenness sheet was not formed with an adhesive, and reflection on the back surface was eliminated. “Murakami Color Research Laboratory, model name: Kakusaku Mitsuzawa GM- Gloss at 60 ° was measured using “3D”.

[Example 1]

 Urethane acrylic UV curable resin (manufactured by Dainippon Ink & Chemicals, Inc., trade name: Dudick) 100 parts by weight, lauryl metatalylate (manufactured by Nippon Oil & Fats Co., Ltd.) 100 parts by weight, benzophenone A coating liquid was prepared by mixing 4 parts by weight of a photopolymerization initiator (Ciba “Specialty” Chemicals, trade name: Irgaki Yua 907) and 106 parts by weight of toluene.

 The resulting coating solution was cloudy because the urethane acrylic UV curable resin and lauryl methacrylate were incompatible.

The coating solution is applied to a polyethylene terephthalate (PET) film (thickness 50 m), dried at 25 ° C for 2 minutes, then irradiated with ultraviolet rays (365 nm, ultraviolet intensity 300 mjZcm ² ) and cured on the PET film. A laminated sheet with a coating (thickness: about 4.1 μm) was produced.

 The laminated sheet is cut into strips, placed in a pressure vessel, pressurized to 40 ° C and 25 MPa, and while maintaining this pressure, carbon dioxide is injected and discharged at a gas flow rate of 5 liters Zmin. The operation to be worried was performed for 2 hours, and the operation to extract lauryl metatalylate was performed.

 The laminated sheet after performing the extraction operation had a fine surface uneven structure showing good antiglare properties.

 Table 1 shows the amount of each reagent and the extraction conditions.

 In addition, the optical properties and surface roughness of the laminated sheet after the extraction operation were measured, and the results are shown in Table 2.

[0066] (Example 2)

A coating solution similar to that in Example 1 was prepared, and the same operation as in Example 1 was performed except that the coating solution was applied to a triacetylcellulose (TAC) film (thickness 50 m). A laminated sheet on which a cured film (thickness of about 4 μm) was formed was obtained.

 The laminated sheet after the extraction operation had a fine surface uneven structure showing good antiglare properties.

 Table 1 shows the blending amount and extraction conditions of each reagent, and the optical properties and surface roughness of the laminated sheet after the extraction operation were measured. The results are shown in Table 2.

[0067] (Example 3)

 A coating solution similar to that in Example 1 was prepared, the coating solution was applied to a triacetyl cellulose (TAC) film (thickness 50 μm), and a cured coating (thickness about 4 μm) was formed on the TAC film. The formed laminated sheet was produced.

 The laminated sheet was cut into strips of 100 mm × 150 mm and immersed in 300 cc of toluene at an ambient temperature of 25 ° C. for 10 minutes to extract lauryl metatalylate.

 The laminated sheet after the extraction operation had a fine surface uneven structure showing good antiglare properties.

 Table 1 shows the blending amount and extraction conditions of each reagent, and the optical properties and surface roughness of the laminated sheet after the extraction operation were measured. The results are shown in Table 2.

[Example 4]

 A cured film (thickness of about 4 m) was formed on the TAC film in the same manner as in Example 2 except that 100 parts by weight of lauryl attalate (Nippon Yushi Co., Ltd.) was used instead of lauryl metatalylate. The formed laminated sheet was produced.

 The operation for extracting lauryl acrylate from the laminated sheet was performed in the same manner as in Example 1.

 The laminated sheet after the extraction operation had a fine surface uneven structure showing good antiglare properties.

 Table 1 shows the blending amount and extraction conditions of each reagent, and the optical properties and surface roughness of the laminated sheet after the extraction operation were measured. The results are shown in Table 2.

 The obtained coating liquid was cloudy because urethane acrylic ultraviolet curable resin and lauryl acrylate were incompatible.

[0069] (Example 5) Acrylic UV curable resin (made by Toa Gosei Co., Ltd., pentaerythritol triatrate) 100 parts by weight, lauryl metatalylate (manufactured by Nippon Oil & Fats Co., Ltd.) 100 parts by weight, benzophenone photopolymerization Initiator (Ciba 'Specialty' Chemicals, trade name: Irgacure 90 7) The same procedure as in Example 1 was carried out except that 4 parts by weight and 106 parts by weight of toluene were mixed to prepare a coating solution. A laminated sheet with a cured film (thickness 3.8 m) formed on a PET film was prepared.

 The operation for extracting lauryl metatalylate from the laminated sheet was performed in the same manner as in Example 1.

 The laminated sheet after the extraction operation had a fine surface uneven structure showing good antiglare properties.

 Table 1 shows the blending amount and extraction conditions of each reagent, and the optical properties and surface roughness of the laminated sheet after the extraction operation were measured. The results are shown in Table 2.

[Example 6]

 Acrylic UV curable resin (manufactured by Toa Gosei Co., Ltd., dipentaerythritol hexatalate) 100 parts by weight, lauryl metatalylate (manufactured by NOF Corporation), benzophenone photopolymerization started The same procedure as in Example 1 was performed except that 4 parts by weight (Ciba 'Specialty' Chemicals, trade name: Irgacure 907) and 106 parts by weight of toluene were mixed to prepare a coating solution. A laminated sheet having a cured coating (thickness 4.6 m) formed on the film was produced.

 The operation for extracting lauryl metatalylate from the laminated sheet was performed in the same manner as in Example 1.

 The laminated sheet after the extraction operation had a fine surface uneven structure showing good antiglare properties.

 Table 1 shows the blending amount and extraction conditions of each reagent, and the optical properties and surface roughness of the laminated sheet after the extraction operation were measured. The results are shown in Table 2.

[Example 7]

Acrylic ultraviolet curable resin (manufactured by Aldrich, tris- (2-hydroxyethyl) isocyanurate triatalylate) 100 parts by weight, lauryl acrylate (manufactured by Nippon Oil & Fats Co., Ltd.) 100 Example 1 except that a coating solution was prepared by mixing 4 parts by weight, 4 parts by weight of benzophenone photopolymerization initiator (Ciba “Specialty” Chemicals, trade name: Irgacure 907) and 106 parts by weight of toluene. In the same manner as described above, a laminated sheet in which a cured coating (thickness 5.1 / zm) was formed on a PET film was produced.

 The operation for extracting lauryl metatalylate from the laminated sheet was performed in the same manner as in Example 1.

 The laminated sheet after the extraction operation had a fine surface uneven structure showing good antiglare properties.

 Table 1 shows the blending amount and extraction conditions of each reagent, and the optical properties and surface roughness of the laminated sheet after the extraction operation were measured. The results are shown in Table 2.

[0072] (Comparative Example 1)

 The same procedure as in Example 1 was conducted except that polyethylene glycol dimethyl ether (manufactured by NOF Corporation, trade name: MM500UOO parts by weight) was used instead of lauryl metatalylate used in Example 1.

 The obtained coating solution was strong in compatibility with urethane acrylic ultraviolet curable resin and polyethylene glycol dimethyl ether, and therefore, no phase separation was observed. As a result, the cured coating (thickness: 4.1 μm) of the laminated sheet had almost no irregularities on the surface, and the antiglare property was extremely insufficient.

 Table 1 shows the blending amount and extraction conditions of each reagent, and the optical properties and surface roughness of the obtained laminated sheet were measured. The results are shown in Table 2.

[0073] (Comparative Example 2)

 The same operation as in Example 5 was performed, except that a coating solution to which lauryl metatalylate was not added was used.

 The obtained coating liquid did not form a phase separation structure, so it was not cloudy, and no phase separation was observed in the ultraviolet curing treatment.

 As a result, the cured coating (thickness 4 μm) of the laminated sheet had almost no irregularities on the surface, and the antiglare property was extremely insufficient.

Table 1 shows the blending amount and extraction conditions of each reagent, and shows the optical properties and surface roughness of the obtained laminated sheet. The results are shown in Table 2.

[0074] (Comparative Example 3)

 The same operation as in Example 6 was performed, except that a coating solution to which lauryl metatalylate was not added was used.

 The obtained coating liquid did not form a phase separation structure, so it was not cloudy, and no phase separation was observed in the ultraviolet curing treatment.

 As a result, the cured coating (thickness 4 μm) of the laminated sheet had almost no irregularities on the surface, and the antiglare property was extremely insufficient.

 Table 1 shows the blending amount and extraction conditions of each reagent, and the optical properties and surface roughness of the obtained laminated sheet were measured. The results are shown in Table 2.

[0075] (Comparative Example 4)

 The same operation as in Example 7 was performed, except that a coating solution to which lauryl metatalylate was not added was used.

 The obtained coating liquid did not form a phase separation structure, so it was not cloudy, and no phase separation was observed in the ultraviolet curing treatment.

 As a result, the cured coating (thickness 4 μm) of the laminated sheet had almost no irregularities on the surface, and the antiglare property was extremely insufficient.

 Table 1 shows the blending amount and extraction conditions of each reagent, and the optical properties and surface roughness of the obtained laminated sheet were measured. The results are shown in Table 2.

[0076] [Table 1]

 PET: Polyethylene terephthalate

TAC: Triacetyl cellulose PEG dimethyl ether: Polyethylene glycol dimethyl ether PETA: Pentaerythritol retriate

 DPEHA: Dipentaerythritol hexaatalylate

 THEIC: Tris-I (2-hydroxyethinole) isocyanurate triatalylate

[0077] [Table 2]

 [0078] It has been found that the uneven surface sheet obtained by the method for producing an uneven surface sheet of the present invention has excellent antiglare properties.

Claims

The scope of the claims  [1] a first step of preparing a coating liquid by mixing an organic resin material and a material incompatible with the organic resin material;  A second step of applying the coating liquid and forming a coating film having a phase-separated structure in which the organic resin material and the incompatible material are phase-separated;  The coating film is subjected to curing treatment, the organic resin material is cured to fix the phase separation structure, and then the incompatible material is removed from the coating film subjected to curing treatment, And a third step of forming a cured resin layer having a concavo-convex structure. [2] a first step of preparing a coating liquid by mixing an organic resin material, a material incompatible with the organic resin material, and a solvent;  A second step of applying the coating liquid and forming a coating film having a phase-separated structure in which the organic resin material and the incompatible material are phase-separated;  After the second step, a solvent removal step for removing the solvent from the coating film, a coating treatment from which the solvent has been removed by the solvent removal step is subjected to a curing treatment, the organic resin material is cured, and the phase separation is performed. And a third step of removing the incompatible material from the cured coating after forming the structure and forming a cured resin layer having a surface uneven structure. A method for producing a surface uneven sheet. [3] The surface unevenness according to claim 1 or 2, wherein the organic resin material is a thermosetting resin or an ultraviolet curable resin, and the curing process in the third step is a heat treatment or an ultraviolet irradiation process. Sheet manufacturing method.  [4] The method for producing a surface uneven sheet according to any one of claims 1 to 3, wherein the incompatible material in the third step is removed by solvent extraction. 5. The method for producing a surface uneven sheet according to claim 4, wherein the solvent used for the solvent extraction is liquefied carbon dioxide or carbon dioxide in a supercritical state. 6. The method for producing an uneven surface sheet according to claim 4, wherein the solvent used for the solvent extraction is an organic solvent that selectively dissolves an incompatible material. [7] The center line average surface roughness (Ra) of the uneven surface sheet is 50-1500 nm, and the average peak-valley spacing (S m) The force is 0 to 400 µm, The method for producing a surface uneven sheet according to any one of claims 1 to 6.  [8] A surface uneven sheet produced by the method for producing a surface uneven sheet according to any one of claims 1 to 7.  [9] An antiglare sheet, wherein the surface uneven sheet manufactured by the method for manufacturing a surface uneven sheet according to any one of claims 1 to 8 is formed on at least one surface of a transparent substrate.