JP6364867B2 - Antireflection article and image display device - Google Patents

Description

  The present invention relates to an antireflection article and an image display device.

  Regarding an antireflection film which is a film-shaped antireflection article, there has been proposed a method for preventing reflection by arranging a large number of minute protrusions in close contact with the surface of a transparent substrate (transparent film) (Patent Document 1). To 3). In this method, the refractive index with respect to incident light is continuously changed in the thickness direction, thereby eliminating the discontinuous interface of the refractive index and preventing reflection.

The film having a large number of microprojections has high antireflection performance. However, due to its surface structure, dirt such as sebum is likely to adhere, and the dirt penetrates into the groove between the microprotrusions, so that it is difficult to remove and the surface appearance tends to deteriorate.

Patent Document 4 describes a fine concavo-convex structure made of a cured product of a specific active energy ray-curable resin composition as a fine concavo-convex structure excellent in contaminant removal and also having scratch resistance. . In Patent Document 4, the cured product of the specific resin composition described above has a specific composition, whereby the crosslink density is increased, the elastic modulus and hardness of the cured product are increased, and the scratch resistance is increased. Contaminant by making it easy to allow water to enter between the surface of the fine concavo-convex structure and the contaminant adhering to the surface. It is described that it has excellent removability.
According to the method of Patent Document 4, since the cross-linking density is increased to increase the hardness of the fine concavo-convex structure, the fine concavo-convex structure is difficult to deform, and it is difficult to reach the gaps of the fine concavo-convex structure during wiping. . Therefore, when wiping off the contaminants, it is necessary to lift off the dirt with a cleaner or the like containing water or alcohol, and the contaminants cannot be removed by dry wiping.

  Further, in Patent Document 5, in an optical element having an antireflection function provided with a structure having fine irregularities on the surface of a substrate, the structure is arranged so that dirt attached to the structure can be removed by dry wiping. It is described that the elastic modulus of the material forming the body and the aspect ratio of the structure are within a specific range. Patent Document 5 describes that when the surface is wiped off, the structure is deformed, and dirt that has penetrated between the structures is pushed out, so that the dirt can be removed.

  On the other hand, in Patent Document 6, by adding a polyrotaxane compound to a flat low-refractive index layer that has been reduced in refractive index by containing low-refractive-index inorganic fine particles, the coated surface state is improved, and coating is improved. It is stated that the pencil hardness of the film has increased. However, the low refractive index layer in this document is a technology that realizes low reflection of about 1.5% by a flat film using low refractive index inorganic fine particles, and suggests that it is applied to a structure having fine irregularities on the surface. There is no.

Japanese Patent Laid-Open No. 50-70040 JP 2004-155083 A JP 2011-33892 A International Publication No. 2012/096322 Pamphlet JP 2011-76072 A JP 2009-204832 A

Conventionally, in order to improve the scratch resistance of an antireflection article, as in Patent Document 4, a cured product of a resin composition forming fine protrusions has been made to have a high crosslinking density. However, the present inventors have found that if the cured product of the resin composition has a high cross-linking density, the microprojections become hard and brittle, resulting in a problem that the scratch resistance is lowered.
On the other hand, when forming a microprotrusion using a resin material having a low elastic modulus as in Patent Document 5, the microprotrusion easily falls down immediately after forming the microprotrusion shape, and the tips of the microprotrusions stick to each other. Sticking is likely to occur. Therefore, the film may have a cloudiness and transparency may be reduced. In addition, a fine uneven layer formed using a resin material having a low elastic modulus is easily deformed by a practical level of wiping pressure, such as protrusions being easily crushed or sticking. May remain. As described above, there is a trade-off relationship between antifouling property and anti-sticking property, and scratch resistance and anti-sticking property, and the antireflection article has all of antifouling property, anti-sticking property and anti-scratch property. It was difficult to get.

  The present invention has been made in view of the above problems, and while being capable of wiping off dirt adhering to the surface, it is possible to suppress a decrease in antireflection performance and to provide an antireflection article excellent in scratch resistance, and a surface. An object of the present invention is to provide an image display device that can suppress the deterioration of the antireflection performance and is excellent in scratch resistance while being able to wipe off the adhered dirt.

The antireflection article according to the present invention has a fine concavo-convex shape provided with a group of microprotrusions in which a plurality of microprotrusions are closely arranged, and a micro concavo-convex layer made of a cured resin composition. An anti-reflective article,
When the shortest wavelength of the wavelength band of light for preventing reflection is Λ _min and the average value of the adjacent protrusion intervals d of the fine protrusions is d _AVG ,
d _AVG ≦ Λ _min
Have the relationship
The storage elastic modulus (E ′) at 25 ° C. of the cured product of the resin composition is 300 MPa or less,
The resin composition contains a polyrotaxane.

  In the antireflection article according to the present invention, it is preferable that the polyrotaxane has a functional group containing an ethylenically unsaturated bond in the cyclic molecule from the viewpoint of improving antifouling property, sticking resistance and scratch resistance.

  In the antireflection article according to the present invention, the content of the polyrotaxane is 0.5 to 30.0 mass% with respect to the total solid content contained in the resin composition. This is preferable from the viewpoint of improving sticking property and scratch resistance.

  The image display device according to the present invention includes the antireflection article according to the present invention on at least one side of a display panel.

  ADVANTAGE OF THE INVENTION According to this invention, while being able to wipe off the stain | pollution | contamination adhering to the surface, while suppressing the fall of antireflection performance and being able to wipe off the stain | pollution | contamination adhering to the surface which can suppress the fall of antireflection performance and was excellent in abrasion resistance In addition, it is possible to provide an image display device that can suppress a decrease in antireflection performance and is excellent in scratch resistance.

It is a schematic cross section shown to an example of the antireflection article concerning the present invention. It is a schematic plan view which shows an example of a Delaunay figure. It is a schematic cross section which shows another example of a fine uneven | corrugated layer. It is the schematic which shows an example of the manufacturing method of the reflection preventing article which concerns on this invention. 1 is a perspective view schematically showing an example of an image display device according to the present invention.

Hereinafter, the antireflection article and the image display device according to the present invention will be described in detail in order.
In this specification, “article” is a concept including aspects such as “plate”, “sheet”, and “film”.
Furthermore, as used in this specification, the shape and geometric conditions and the degree thereof are specified. For example, terms such as “parallel”, “orthogonal”, “identical”, length and angle values, etc. Without being bound by meaning, it should be interpreted including the extent to which similar functions can be expected.
In the present invention, (meth) acryl represents each of acryl or methacryl, (meth) acrylate represents each of acrylate or methacrylate, and (meth) acryloyl represents each of acryloyl or methacryloyl.
Moreover, the hardened | cured material of a resin composition in this invention means what solidified through the chemical reaction.

[Anti-reflective article]
The antireflection article according to the present invention has a fine concavo-convex shape provided with a group of microprotrusions in which a plurality of microprotrusions are closely arranged, and a micro concavo-convex layer made of a cured resin composition. An anti-reflective article,
When the shortest wavelength of the wavelength band of light for preventing reflection is Λ _min and the average value of the adjacent protrusion intervals d of the fine protrusions is d _AVG ,
d _AVG ≦ Λ _min
Have the relationship
The resin composition contains a polyrotaxane.

The antireflection article according to the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing an example of an antireflection article according to the present invention. An antireflection article 10 illustrated in FIG. 1 has a fine uneven layer 2 having a fine uneven shape on one surface side of a transparent substrate 1.
Wherein the surface of the fine uneven layer 2 is a fine uneven surface 2a having a fine projection group fine projections 3 will be set, the microprojections 3, the shortest wavelength in the wavelength band of light to improve the anti-reflection lambda _min In addition, when the average value of the adjacent protrusion interval d (FIG. 1) of the minute protrusion 3 is d _AVG , the relationship of d _AVG ≦ Λ _{min is} established, thereby preventing reflection of light having a wavelength of Λ _min or more. be able to.

The present inventors have paid attention to the fact that pressure is applied to the fine protrusions when wiping the contaminants attached to the surface of the fine uneven layer. The inventors of the present invention designed that the microprotrusions and the fine concavo-convex layer as a whole are deformed by the pressure at the time of wiping, so that the grooves between the protrusions are widened, or the grooves between the protrusions are filled. We thought that it would be possible to mechanically scrape off the contaminants adhering to the surface and wipe off the dirt. However, when the microprotrusions are formed using a resin material having a low elastic modulus as described in Patent Document 5, the microprotrusions easily fall down, and sticking in which the tips of the microprotrusions stick to each other easily occurs. For this reason, the wiping pressure may cause plastic deformation such as easily crushing the protrusion or causing sticking, and a wiping mark may remain at the wiped portion. In addition, when the hydrophilic resin material is used, the inventors of the present invention make it easier for the protrusions to be attracted to each other through the polarity of the water molecules when the dirt is removed with water. It was found that is likely to occur.
In this invention, a fine uneven | corrugated layer consists of the hardened | cured material of the resin composition containing a polyrotaxane. The polyrotaxane is designed so that the cyclic molecules are not released at both ends of the pseudo-polyrotaxane formed by penetrating the openings of two or more cyclic molecules in a skewered manner, and the cyclic molecules include the linear molecules. A block group is arranged. The cyclic molecule possessed by the polyrotaxane can slide and move on the linear molecule in a state where the linear molecule is included. Therefore, in the fine uneven layer in the present invention, due to an external force such as pressure applied when wiping, the cyclic molecule that the polyrotaxane has slides on the linear molecule and moves, and molecules that exist around the cyclic molecule are also included. It is considered that the intermolecular force acts to move with the cyclic molecule. Therefore, in the fine uneven layer according to the present invention, the external force is not concentrated on one point, and it is considered that the fine protrusions and the entire fine uneven layer are easily deformed by the external force, and as a result, the dirt between the fine protrusions is easy. It can be wiped off.
Further, when the cyclic molecules existing on the same axis in the polyrotaxane approach each other, it is considered that the cyclic molecules move so as to keep the mutual distance constant in order to maintain entropy. Thereby, since the fine uneven layer deformed by an external force is easily restored to the original shape, the antireflection article according to the present invention suppresses the deformation of the fine protrusions and the sticking where the fine protrusions adhere to each other. It is considered that the deterioration of the antireflection performance due to deformation and sticking can be suppressed. Furthermore, since the fine uneven layer in the present invention can disperse internal stress and prevent the destruction of the structure, it is considered that the scratch resistance is improved.
As described above, the antireflection article according to the present invention has a high toughness that can be easily deformed against an external force and restored to its original shape because the fine uneven layer contains polyrotaxane. Therefore, while it is possible to easily wipe off the dirt between the microprotrusions, the deterioration of the antireflection performance due to deformation of the microprotrusions and sticking is suppressed, and the scratch resistance is excellent.

<Fine uneven layer>
The fine concavo-convex layer provided in the antireflection article according to the present invention has a fine concavo-convex shape provided with a group of fine protrusions in which a plurality of fine protrusions are closely arranged, and is formed of a cured product of the resin composition.
[Resin composition]
The resin composition for the fine uneven layer is preferably a photocurable resin composition containing at least a polyrotaxane.
In the present invention, the linear molecule contained in the polyrotaxane is a molecule or substance that is included in the cyclic molecule and can be integrated non-covalently, and is not particularly limited as long as it is linear. Not. In the present invention, the “linear molecule” refers to a molecule including a polymer and all other substances satisfying the above requirements. Further, in one polyrotaxane, the plurality of cyclic molecules may include one linear molecule, or include two or more linear molecules bundled together. May be.
In the present invention, “linear” of “linear molecule” means substantially “linear”. That is, the linear molecule may have a branched chain as long as the cyclic molecule that is a rotor is rotatable or the cyclic molecule is slidable or movable on the linear molecule. Further, the length of the “straight chain” is not particularly limited as long as the cyclic molecule can slide or move on the linear molecule.

The polyrotaxane used in the present invention is not particularly limited, but preferably has a reactive group. When the polyrotaxane has a reactive group, the polyrotaxanes or the polyrotaxane and a compound having another reactive group can form a crosslinking point. Since the cross-linking point maintains the cross-linking bond even when an external force is applied, the restorability of the microprojections and the fine concavo-convex layer is improved. On the other hand, even if it has the cross-linking point, the cyclic molecules and the peripheral molecules can move by applying an external force, so that the ease of deformation of the microprojections and the entire micro uneven layer is maintained.
In the present invention, it is more preferable that the polyrotaxane has a reactive group in the cyclic molecule. Thereby, a cyclic point can be formed between cyclic molecules or a compound having a cyclic molecule and another reactive group. Since the cyclic molecule of polyrotaxane can slide and move on a linear molecule, the crosslinking point itself can move at the crosslinking point formed by the cyclic molecule. Therefore, the fine concavo-convex layer is more easily deformed while improving the restoration property. Thereby, the antireflection article according to the present invention further improves the wiping property and scratch resistance between the fine uneven layers, and also suppresses sticking.
Moreover, as a polyrotaxane used in the present invention, a crosslinked polyrotaxane in which cyclic molecules are previously crosslinked may be used.

  The reactive group is not particularly limited as long as it can form a cross-linked bond. For example, an ethylenically unsaturated group such as a (meth) acryloyl group, a vinyl group, a vinyl ether group, a styryl group, or an allyl group. Functional group containing a bond (hereinafter sometimes referred to as an ethylenically unsaturated bond-containing group), cinnamoyl group, cinnamylidene group, chalcone residue, isocoumarin residue, 2,5-dimethoxystilbene residue, thymine residue, still Examples include unsaturated bond groups such as pyridinium residues, α-phenylmaleimide residues, anthracene residues, and 2-pyrone residues, hydroxyl groups, amino groups, carboxyl groups, thiol groups, aldehyde groups, and the like. The bond-containing group is preferable from the viewpoint of good reactivity with ultraviolet irradiation and excellent mass productivity.

  Examples of the linear molecule include polyvinyl alcohol, polyvinyl pyrrolidone, poly (meth) acrylic acid, cellulose resins (carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, etc.), polyacrylamide, polyethylene oxide, polyethylene glycol, and polyvinyl acetal. Hydrophilic polymers such as resin, polyvinyl methyl ether, polyamine, polyethyleneimine, casein, gelatin, starch and / or copolymers thereof; for example, copolymer resins with polyethylene, polypropylene, and other olefinic monomers, etc. Polyolefin resin, polyester resin, polyvinyl chloride resin, polystyrene resin such as polystyrene and acrylonitrile-styrene copolymer resin, polymethyl Hydrophobic polymers such as methacrylate, (meth) acrylic acid ester copolymers, acrylic resins such as acrylonitrile-methyl acrylate copolymer resins, polycarbonate resins, polyurethane resins, vinyl chloride-vinyl acetate copolymer resins, polyvinyl butyral resins; and These derivatives or modified products can be mentioned. In the present invention, the linear molecule is preferably a polyalkylene glycol, an aliphatic polyester, a polyolefin, a polydiene or a polydialkylsiloxane; more preferably a polyethylene glycol derivative, a polypropylene glycol derivative, a polytetra Methylene glycol derivatives, polybutyrolactone derivatives, polycaprolactone derivatives, polyethylene derivatives, polypropylene derivatives, polybutene derivatives, polyisoprene derivatives, polybutadiene derivatives, polydimethylsiloxane derivatives; particularly preferably polyethylene glycol derivatives, polypropylene glycol derivatives, polyethylene derivatives, polypropylene derivatives , A polydimethylsiloxane derivative.

  The weight average molecular weight of the linear molecule increases the working range of the cyclic molecule, increases the number of introduction of the cyclic molecule, and improves the sticking resistance, scratch resistance and antifouling property due to the movement of the cyclic molecule. Is preferably 1,000 or more, more preferably 5,000 or more, and still more preferably 10,000 or more. In addition, the weight average molecular weight of the linear molecule is preferably 1,000,000 or less, more preferably 500,000 or less, from the viewpoints of resin material stability and moldability of fine irregularities. Preferably, it is still more preferably 300,000 or less. In addition, the weight average molecular weight here is calculated | required as a standard polystyrene conversion value by gel permeation chromatography (GPC).

  The linear molecule of the present invention preferably has reactive groups at both ends. By having this reactive group, it can react easily with a blocking group. Although a reactive group is dependent on the block group to be used, a hydroxyl group, an amino group, a carboxyl group, a thiol group etc. can be mentioned, for example. In the present invention, the linear molecule may have the reactive group. The linear molecule having an ethylenically unsaturated bond-containing group as the reactive group includes, for example, a reactive group such as a hydroxyl group that the linear molecule has, a functional group capable of reacting with the reactive group, and an ethylenically unsaturated group. It can be obtained by reacting a compound having a saturated bond.

  The cyclic molecule is not particularly limited as long as it can include the linear molecule and has a substantially cyclic structure. Here, “substantially a cyclic structure” means that the structure includes a structure in which a part of the ring is interrupted, a helical structure in which one end of the molecule is not bonded to the other end, and the like.

  Examples of the cyclic molecule include cyclodextrins such as α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, dimethylcyclodextrin and glucosylcyclodextrin, derivatives or modified products thereof, crown ethers, benzocrowns, dibenzo Examples include crowns, dicyclohexano crowns, derivatives or modified products thereof, and the like. Among these, cyclodextrins are preferable, and α-cyclodextrin is particularly preferable.

  The number (inclusion amount) of the cyclic molecule that includes the linear molecule is not particularly limited, but when the cyclic molecule is closely packed and included in the cyclic molecule linear molecule (filling rate: 100%). The introduction rate (inclusion rate) of cyclic molecules that include linear molecules when the inclusion amount is expressed as a maximum inclusion rate of 1.0 is preferably 0.05 to 0.80. When the linear molecule is a polyethylene glycol derivative and the cyclic molecule is a cyclodextrin, the inclusion rate is preferably 0.05 to 0.65, and preferably 0.10 to 0.60. Is more preferably 0.15 to 0.55, and particularly preferably 0.20 to 0.40. When the inclusion rate is within the above range, the fine uneven layer is easily deformed, and is excellent in antifouling property and scratch resistance. The maximum inclusion amount of the cyclic molecule can be determined from the length of the linear molecule and the thickness of the cyclic molecule. For example, the maximum inclusion amount when the linear molecule is a polyethylene glycol derivative and the cyclic molecule is α-cyclodextrin is calculated by the method described in, for example, Macromolecules, 1993, Vol 26, 5698-5703. Can do. The inclusion rate can be calculated from, for example, the content of cyclic molecules and the content of linear molecules measured by 1H-NMR.

The cyclic molecule preferably has the ethylenically unsaturated bond-containing group. Examples of a method for introducing an ethylenically unsaturated bond-containing group into the cyclic molecule include conventionally known methods. For example, at least a part of the hydroxyl group of a cyclic molecule having a hydroxyl group (—OH) such as cyclodextrin is used. This can be carried out by substitution with an ethylenically unsaturated bond-containing group.
Examples of a method for introducing an ethylenically unsaturated bond-containing group into the cyclic molecule include a method by carbamate bond formation with an isocyanate compound or the like; a method by ester bond formation with a carboxylic acid compound, an acid chloride compound, or an acid anhydride; A conventionally known method such as a method by silyl ether bond formation with a compound or the like; a method by carbonate bond formation with a chlorocarbonic acid compound or the like can be mentioned.

  The step of substituting a reactive group such as a hydroxyl group in the cyclic molecule with an ethylenically unsaturated bond-containing group may be before the step of preparing the pseudopolyrotaxane, between the steps, or after the step. Further, it may be before the step of preparing the polyrotaxane by blocking the pseudopolyrotaxane, between the steps, or after the step. The conditions used in the substitution step depend on the ethylenically unsaturated bond-containing group to be substituted, but are not particularly limited, and various reaction methods and reaction conditions can be used.

The cyclic molecule may have another reactive group different from the ethylenically unsaturated bond-containing group. In the case of having other reactive groups, this allows the cyclic molecule to bind to another cyclic molecule or other molecule or to be cross-linked using a cross-linking agent as required.
Examples of other reactive groups include a hydroxyl group, an amino group, a carboxyl group, a thiol group, and an aldehyde group. Further, it is preferable to use a group that does not react with the blocking group.

  The cyclic molecule may be one in which two or more cyclic molecules are chemically bonded to each other. The cyclic molecule may be chemically modified. Specifically, for example, a hydrophobized modified polyrotaxane in which at least one of hydroxyl groups of cyclodextrins is substituted with another organic group (hydrophobic group) is preferably used from the viewpoint of improving the solubility in a solvent.

When the cyclic molecule is a cyclodextrin, at least one of the hydroxyl groups of the cyclodextrin is substituted with a hydrophobic group (hereinafter sometimes referred to simply as a hydrophobic group). This is preferable from the viewpoint of improving the solubility.
Examples of hydrophobic groups include alkyl groups, benzyl groups, benzene derivative-containing groups, acyl groups, silyl groups, trityl groups, nitrate ester groups, tosyl groups, alkyl-substituted ethylenically unsaturated groups as photocuring sites, and alkyl groups as thermosetting sites. Examples thereof include a substituted epoxy group. Moreover, in said hydrophobic modification polyrotaxane, you may have 1 type of the above-mentioned hydrophobic group individually or in combination of 2 or more types.
The ratio of the number of hydroxyl groups modified by the hydrophobic modifying group to the total number of hydroxyl groups is preferably 0.02 or more, and 0.04 or more, assuming that the total number of hydroxyl groups possessed by cyclodextrin is 1. Is more preferable, and it is still more preferable that it is 0.06 or more. By being more than the said lower limit, it is excellent in the solubility to an organic solvent.
Introducing an ethylenically unsaturated bond-containing group or other reactive group and a hydrophobic group is preferable from the viewpoint of improving the reactivity with other molecules while improving the solubility.

As the blocking group disposed at both ends of the linear molecule, any group may be used as long as the linear molecule keeps the state in which the linear molecule penetrates through the opening of the cyclic molecule, There is no particular limitation. Here, the “group” means various groups including a molecular group and a polymer group.
Examples of the blocking group include a group having “bulkiness” and a group having “ionicity”. In addition, the group having “ionicity” can maintain a state in which a linear molecule is skewered through the opening of the cyclic molecule, for example, by repelling the “ionicity” of the cyclic molecule. it can. Specific examples of the blocking group include, for example, groups derived from dinitrobenzenes such as 2,4-dinitrophenyl group and 3,5-dinitrophenyl group, groups derived from cyclodextrins, and adamantane groups such as adamantyl group. Groups, groups derived from triphenylmethanes such as trityl groups, groups derived from fluoresceins, groups derived from pyrenes, groups derived from substituted benzenes, optionally substituted polynuclear aromatic groups, groups derived from steroids, etc. Is mentioned. Among these, a group derived from dinitrobenzenes, a group derived from cyclodextrins, a group derived from adamantanes, a group derived from triphenylmethanes, a group derived from fluoresceins, or a group derived from pyrenes is preferable. -Dinitrophenyl group, 3,5-dinitrophenyl group, 2,4-diphenylphenyl group, 2,4-diisopropylphenyl group, 2,4-di-t-butylphenyl group, 4-diphenylaminophenyl group, 4- It is a diphenylphosphinylphenyl group, an adamantyl group, or a trityl group, and particularly preferably a 2,4-dinitrophenyl group, a 3,5-dinitrophenyl group, an adamantyl group, or a trityl group. The blocking groups provided at both molecular ends of the polyrotaxane of the present invention may be the same or different from each other. Further, the blocking group may have an ethylenically unsaturated bond-containing group.

The content of the polyrotaxane is preferably 0.5 to 30% by mass, more preferably 3 to 30.0% by mass, more preferably 5 to 3% by mass with respect to the total solid content contained in the resin composition. It is still more preferable that it is 20.0 mass%. When the content is equal to or higher than the lower limit, the dirt wiping property and the scratch resistance are improved, and the effect of suppressing the decrease in the antireflection performance is improved. When the content is less than or equal to the upper limit, moldability is improved and antireflection performance is improved. If the content exceeds the upper limit, resin coatability and transferability may be deteriorated.
In addition, in this invention, solid content represents all the components except a solvent.

Moreover, it is preferable that the resin composition for fine uneven | corrugated layers used for this invention contains a curable resin component. As the curable resin component, a photocurable component is preferable. When the polyrotaxane has a reactive group, a compound having a reactive group capable of reacting with the polyrotaxane is more preferable. Among them, it is preferable to use a compound having an ethylenically unsaturated bond-containing group capable of reacting with the polyrotaxane in combination with a polyrotaxane having a functional group containing an ethylenically unsaturated bond, and in particular, a (meth) acrylate compound is used. preferable.
The (meth) acrylate is a polyfunctional acrylate having two or more (meth) acryloyl groups in one molecule, even if it is a monofunctional (meth) acrylate having one (meth) acryloyl group in one molecule. Alternatively, monofunctional (meth) acrylate and polyfunctional (meth) acrylate may be used in combination.
Especially, it is preferable to use a monofunctional (meth) acrylate and a polyfunctional (meth) acrylate together from the point which balances a softness | flexibility and an elastic restoring property.

Specific examples of monofunctional (meth) acrylates include, for example, methyl (meth) acrylate, hexyl (meth) acrylate, decyl (meth) acrylate, allyl (meth) acrylate, benzyl (meth) acrylate, butoxyethyl (meth) acrylate , Butoxyethylene glycol (meth) acrylate, cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, glycerol (meth) acrylate, glycidyl (meth) acrylate, 2-hydroxyethyl (meth) ) Acrylate, 2-hydroxypropyl (meth) acrylate, isobornyl (meth) acrylate, isodexyl (meth) acrylate, isooctyl (meth) acrylate, lauryl (meth) acrylate Relate, 2-methoxyethyl (meth) acrylate, methoxyethylene glycol (meth) acrylate, phenoxyethyl (meth) acrylate, stearyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, biphenyloxyethyl acrylate, bisphenol A diglycidyl (meth) acrylate, biphenylyloxyethyl (meth) acrylate, ethylene oxide modified biphenylyloxyethyl (meth) acrylate, bisphenol A epoxy (meth) acrylate, and the like. Among these, from the viewpoint of excellent flexibility, monofunctional (meth) acrylates having a long-chain alkyl group having 10 or more carbon atoms are preferable, and among these, 12 or more carbon atoms are more preferable, and tridecyl (meth) acrylate and dodecyl are preferable. It is even more preferable that at least one of (meth) acrylates is included. These monofunctional (meth) acrylic acid esters can be used alone or in combination of two or more. In addition, when using the monofunctional (meth) acrylate which has a C10 or more long-chain alkyl group, it has the characteristic of the compound which has a C10 or more long-chain alkyl group mentioned later.
The content of the monofunctional (meth) acrylate is preferably 0 to 40% by mass, more preferably 5 to 40% by mass, and more preferably 10 to 30% by mass with respect to the total solid content of the resin composition. % Is even more preferred.

Specific examples of the polyfunctional acrylate include, for example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, propylene di (meth) acrylate, hexanediol di (meth) acrylate, and polyethylene glycol di (meth) acrylate. Bisphenol A di (meth) acrylate, tetrabromobisphenol A di (meth) acrylate, bisphenol S di (meth) acrylate, butanediol di (meth) acrylate, di (meth) acrylate phthalate, ethylene oxide modified bisphenol A di ( (Meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, tri (Acryloxyethyl) isocyanurate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, urethane tri (meth) acrylate, ester tri (meth) acrylate, urethane hexa (meth) acrylate, ethylene oxide modified tri Examples include methylolpropane tri (meth) acrylate. It is preferable to use a polyfunctional (meth) acrylate containing an alkylene oxide, more preferably to use an ethylene oxide-modified polyfunctional (meth) acrylate, since the microprotrusions have elastic resilience and also have flexibility. It is even more preferable to include at least one selected from ethylene oxide-modified bisphenol A di (meth) acrylate, ethylene oxide-modified trimethylolpropane tri (meth) acrylate, and polyethylene glycol di (meth) acrylate.
It is preferable that content of the said polyfunctional (meth) acrylate is 10-99 mass% with respect to the total solid of the said resin composition, and it is more preferable that it is 15-90 mass%. From the viewpoint of antifouling property and anti-sticking property, the polyfunctional (meth) acrylate containing alkylene oxide is preferably 30 parts by mass or more with respect to 100 parts by mass of the total amount of the (meth) acrylate compound used. Further, it is preferably 50 parts by mass or more.

The resin composition for a fine concavo-convex layer used in the present invention may use a (meth) acrylate having a hydroxyl group and a polyvalent isocyanate compound from the viewpoint of the elastic restoring property of the fine protrusions. When the polyrotaxane has a hydroxyl group, the polyvalent isocyanate compound can also function as a crosslinking agent between the polyrotaxanes. Specific examples of the polyvalent isocyanate compound include, for example, 1,5-naphthylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 4,4′-diphenyldimethylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, cyclohexane-1,4 -Diisocyanate, xylylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis (iso Anetomechiru) cyclohexane, methylcyclohexane diisocyanate, 4,4'-diphenyl ether diisocyanate, 4,4'-diphenyl sulfoxide diisocyanate, 4,4'-diphenyl sulfone diisocyanate, 4,4'-biphenyl diisocyanate and derivatives thereof.
The content of the polyvalent isocyanate compound is preferably 0 to 30% by mass, more preferably 5 to 30% by mass, and more preferably 10 to 20% by mass with respect to the total solid content of the resin composition. It is more preferable that

Moreover, it is preferable that the resin composition for fine uneven | corrugated layers used for this invention contains the compound which has a C10 or more long-chain alkyl group from the point which is excellent in the softness | flexibility of hardened | cured material. The carbon number is more preferably 12 or more.
Specific examples of the compound having a long chain alkyl group having 10 or more carbon atoms include compounds having decane, dodecane, tridecane, tetradecane, pentadecane, hexadecane, and the like. Moreover, unless the effect of this invention is impaired, you may have a substituent further. Specific examples of the substituent include halogen atoms such as fluorine, chlorine and bromine, hydroxyl groups, carboxy groups, amino groups and sulfo groups, as well as ethylenically unsaturated double bonds such as vinyl groups and (meth) acryloyl groups. Groups and the like. Especially, it is preferable to have an ethylenically unsaturated double bond from a point provided with photocurability, and it is more preferable to have a (meth) acryloyl group.
In addition, when the compound which has a C10 or more long-chain alkyl group has a (meth) acryloyl group, the said compound may correspond also to the said (meth) acrylate.
When using the compound which has a C10 or more long-chain alkyl group, it is preferable that content of the said compound is 5-30 mass% with respect to the total solid of the said resin composition, and 7-20 mass % Is more preferable.

The fine concavo-convex layer resin composition used in the present invention may further contain a photopolymerization initiator, if necessary. Specific examples of the photopolymerization initiator include, for example, bisacylphosphinoxide, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, and 2,2-dimethoxy-1. , 2-Diphenylethane-1-one, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 2-methyl-1- [4- (Methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-hydroxy-2-methyl-1-phenyl -Propane-1-ketone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, phenylbis (2,4,6-trimethylbenzene) Benzoyl) - phosphine oxide, phenyl (2,4,6-trimethylbenzoyl) ethyl phosphinic acid and the like. These can be used alone or in combination of two or more.
Content of the said photoinitiator is 0.8-20 mass% normally with respect to the total solid contained in the said resin composition, and it is preferable that it is 0.9-10 mass%.

  The resin composition may further contain a solvent from the viewpoint of imparting coatability, etc., and does not react with each component in the composition and is appropriately selected from solvents that can dissolve or disperse each component. It can be selected and used. Specific examples of such solvents include hydrocarbon solvents such as benzene and hexane, ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone, tetrahydrofuran, 1,2-dimethoxyethane, propylene glycol monoethyl ether ( PGME) ether solvents such as chloroform and dichloromethane, halogenated alkyl solvents such as methyl acetate, ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate and other amide solvents such as N, N-dimethylformamide And sulfoxide solvents such as dimethyl sulfoxide, anone solvents such as cyclohexane, and alcohol solvents such as methanol, ethanol, and propanol, but are not limited thereto. Not to. Moreover, the solvent used for a resin composition may be used individually by 1 type, and the mixed solvent of two or more types of solvents may be sufficient as it.

  The ratio of the solid content with respect to the total amount of the resin composition is preferably 20 to 70% by mass, and more preferably 30 to 60% by mass.

The resin composition may further contain other components as long as the effects of the present invention are not impaired. Other components include, for example, a surfactant for adjusting wettability, a silane coupling agent for improving adhesion, a stabilizer, an antifoaming agent, a repellency inhibitor, an antioxidant, an anti-aggregation agent, and a viscosity. A preparation agent, an antistatic agent, etc. are mentioned.
By containing the antistatic agent, the resin composition can suppress the adhesion of dirt on the surface of the fine concavo-convex layer, and the dirt is easily removed during wiping.
The antistatic agent can be appropriately selected from conventionally known ones. Specific examples of the antistatic agent include, for example, various cationic compounds having a cationic group such as a quaternary ammonium salt, a pyridinium salt, and a primary to tertiary amino group, a sulfonate group, a sulfate ester base, and a phosphate ester. Bases, anionic compounds having an anionic group such as phosphonic acid bases, amphoteric compounds such as amino acid series and aminosulfate ester series, nonionic compounds such as amino alcohol series, glycerin series and polyethylene glycol series, tin and titanium alkoxides And metal chelate compounds such as acetylacetonate salts thereof. Of these, cationic compounds are preferred, cationic compounds having a tertiary amino group are more preferred, and trialkylamines such as N, N-dioctyl-1-octaneamine are even more preferred.
When using an antistatic agent, the content of the antistatic agent is usually preferably 1 to 20% by mass, more preferably 2 to 10% by mass, based on the total solid content of the resin composition. preferable.

  In the present invention, the cured product of the resin composition is at least one selected from another cyclic molecule, the linear molecule, and the curable resin component, at least a part of the plurality of cyclic molecules of the polyrotaxane. It is preferable to have a cross-linking point between the cyclic molecule and the cross-linking point between the cyclic molecule and the curable resin component. As a result, the fine uneven layer is more easily deformed with respect to external force and the resilience is improved, the dirt wiping property and the scratch resistance are improved, and the effect of suppressing the decrease in the antireflection performance is also improved.

In the cured product of the resin composition, the polyrotaxane preferably has an ethylenically unsaturated bond, and the ethylenically unsaturated bond reacts at a reaction rate of 80 to 100%, preferably 90 to 99%. It is more preferable that the reaction occurs at a reaction rate of As a result, the fine uneven layer is more easily deformed with respect to external force and the resilience is improved, the dirt wiping property and the scratch resistance are improved, and the effect of suppressing the decrease in the antireflection performance is also improved.
The said reaction rate can be calculated by a conventionally well-known method, for example, can be determined from the measurement result of the infrared spectrum (IR) of a fine uneven | corrugated layer.

From the viewpoint of excellent flexibility, the resin composition preferably has a storage elastic modulus (E ′) at 25 ° C. of the cured product of the resin composition of 300 MPa or less, more preferably 10 to 250 MPa, Even more preferably, it is 50-200 MPa.
Moreover, since it is excellent in resilience after pressing, the ratio of loss elastic modulus (E ″) to storage elastic modulus (E ′) at 25 ° C. of the cured product of the resin composition (tan δ (= E ″ / E ')) Is preferably 0.2 or less, and more preferably 0.1 or less.

In the present invention, the storage elastic modulus (E ′) and the loss elastic modulus (E ″) are measured by the following method in accordance with JIS K7244.
First, the resin composition is sufficiently cured by irradiating ultraviolet rays having an energy of 2000 mJ / cm ² for 1 minute or more, and has a base material and a fine uneven shape, a thickness of 1 mm, a width of 5 mm, and a length of 30 mm. Single film.
Next, by applying a cyclic external force of 25 g at 10 Hz in the length direction of the cured product of the resin composition at 25 ° C. and measuring dynamic viscoelasticity, E ′ and E ″ at 25 ° C. are obtained. As the measuring device, for example, Rhegel E400 manufactured by UBM is used.

[Fine uneven shape]
The fine concavo-convex layer has on the surface a fine concavo-convex shape provided with a fine protrusion group in which a plurality of fine protrusions are closely arranged. The shape of the microprotrusions is superior in antireflection performance, and the cross-sectional area occupancy rate of the material part forming the microprotrusions in the horizontal cross section when assuming that the microprotrusions are cut in a horizontal plane perpendicular to the depth direction of the microprotrusions However, it is preferable to have a structure that gradually increases gradually from the top of the microprotrusion toward the deepest portion. Specific examples of the shape of such minute protrusions include those having a vertical cross-sectional shape such as semicircular, semielliptical, triangular, parabolic, bell-shaped. The plurality of microprojections may have the same shape or different shapes. Since the minute protrusions have the above-described shape, the refractive index continuously changes in the depth direction of fine irregularities and the like, so that the antireflection performance is improved.

In the present invention, the distance d between adjacent protrusions and the height H of the minute protrusions are measured by the following method.
(1) First, an in-plane arrangement of projections (planar shape of the projection arrangement) is detected using an atomic force microscope (AFM) or a scanning electron microscope (SEM).

  (2) Subsequently, a maximum point of the height of each protrusion (hereinafter simply referred to as a maximum point) is detected from the obtained in-plane arrangement. There are various methods for obtaining the maximum point, such as a method of sequentially comparing the planar view shape and the enlarged photograph of the corresponding cross-sectional shape to obtain the maximum point, and a method of obtaining the maximum point by image processing of the plan view enlarged photo. Can be applied.

(3) Next, a Delaunay diagram with the detected maximum point as a generating point is created. FIG. 2 is a schematic plan view showing an example of a Delaunay diagram. As shown in the example of FIG. 2, the Delaunay diagram is defined by defining the mother points adjacent to each other in the Voronoi region as adjacent mother points when the Voronoi division is performed with the local maximum points 31 of the microprojections 3 as the mother points. This is a net-like figure composed of a triangular aggregate obtained by connecting adjacent base points with a line segment 32. Each triangle is called a Delaunay triangle, and a side of each triangle (a line segment connecting adjacent generating points) is called a Delaunay line.

  (4) Next, from the enlarged photograph of the frequency distribution of the line length of each Delaunay line, that is, the distance between adjacent maximum points (distance between adjacent protrusions) in a plan view, about 5 to 20 of the above-mentioned minute adjacent to each other Select a microprojection that does not have a structure, sample the value of the distance between adjacent projections, and clearly deviate from the numerical range obtained by sampling (typically the average distance between adjacent projections obtained by sampling) The frequency distribution is detected by excluding data whose value is 1/2 or less of the value.

(5) The frequency distribution of the distance d between adjacent protrusions thus determined is regarded as a normal distribution, and the average value d _AVG and the standard deviation σ _d are determined. In the present invention, the maximum value d _max of the distance d between adjacent protrusions is calculated as d _max = d _AVG + 2σ _d .

A similar technique is applied to define the height of the protrusion. In this case, a relative height difference of each local maximum point position from a specific reference position is acquired from the local maximum point obtained by the above (2), and is histogrammed. The average value H _AVG of the projection height and the standard deviation σ _H are obtained from the frequency distribution based on this histogram. In addition, in the case where a microprojection having a fine structure in which a concave portion exists on the top of the projection or a microstructure in which the top is split into a plurality of peaks is included, one microprojection has a plurality of vertices. The plurality of data are mixed in the histogram of the protrusion height H for one protrusion. Therefore, in this case, the frequency distribution is obtained by adopting the vertex having the highest height from among the plurality of vertices belonging to the same microprotrusion as the protuberance.

The reference position for measuring the height of the microprojections is the base position of the projection, that is, the valley bottom (minimum point of height) between the adjacent microprojections is used as the reference for the height 0. However, when the height of the valley bottom itself varies depending on the location, for example, when the envelope surface 2b connecting the valley bottoms between the microprotrusions has a concavo-convex shape with a large period compared to the distance between adjacent protrusions of the microprotrusions. (Refer to FIG. 3): (1) First, an area that is sufficient to converge the average value of the height of each valley bottom measured from the surface opposite to the fine uneven surface 2a of the fine uneven layer 2 Calculate in (2) Next, a surface having the average height and parallel to the surface opposite to the fine uneven surface 2a of the fine uneven layer 2 is considered as a reference surface. (3) Then, the height of each microprotrusion from the reference surface is calculated by setting the reference surface to a height of 0 again.

When the period D of the uneven surface due to the undulation is not constant over the entire surface and has a distribution, the frequency distribution of the distance between the protrusions is obtained for the uneven surface, the average value is D _AVG , and the standard deviation is Σ. When
D _min = D _AVG -2Σ
Designed as an alternative to period D with minimum inter-protrusion distance D _min defined as That is, the conditions that can sufficiently exhibit the scattering effect of the residual reflected light on the uneven surface 2a of the fine uneven layer 2 are as follows:
D _min > λ _MAX
It is. Usually, D or D _min is 1 to 200 μm, preferably 10 to 100 μm.

  Further, in order to ensure good smoothness of the antireflection article, the height difference (h in FIG. 3) of the uneven surface wavy in the period D is preferably 10 nm or less, and is in the range of 1 nm to 5 nm. It is more preferable that The height difference of the uneven surface formed by the uneven surface can be obtained by measuring the height difference of the position of the valley bottom portion of the minute protrusion separated by, for example, 500 nm or more. The position of the valley bottom of the microprojection can be obtained by observing the antireflection article using a TEM photograph or SEM photograph of a vertical section cut in the thickness direction.

When each microprotrusion in the microprotrusion group has the same height H and the microprotrusions are regularly arranged with a constant period, the adjacent protrusion interval d matches the period p of the microprotrusion array. d _AVG = p. Accordingly, the condition that the antireflection effect can be exhibited is d _AVG = p ≦ Λ _min , and the antireflection effect can be exhibited with respect to light having a wavelength longer than or equal to the period p of the microprojection array (for example, see Japanese Patent Application Laid-Open No. Sho-sho). No. 50-70040, Japanese Patent No. 4632589, and Japanese Patent No. 4270806). Therefore, for example, in order to obtain an antireflection effect for all wavelengths in the visible light band, when the shortest wavelength in the visible light band is 380 nm, the period of the microprojection array may be set to 380 nm or less. The height H of the microprojections is preferably 0.2 times or more of the longest wavelength Λ _max among the wavelengths for obtaining the antireflection effect (H ≧ 0.2 × Λ _max ). Therefore, for example, in order to obtain an excellent antireflection effect for all wavelengths in the visible light band, when the longest wavelength in the visible light band is 780 nm, H ≧ 0.2 × 780 nm = 156 nm. Is preferred.

When the protrusions are irregularly arranged, the average value d _{AVG of the} distance d between adjacent protrusions obtained as described above needs to satisfy d _AVG ≦ Λ _min , and the maximum value d _max = It is preferable that d _AVG + 2σ _d satisfies d _max ≦ Λ _min . Mean _{H AVG} height H of the minute projections _preferably satisfies the _{H AVG} ≧ 0.2 × _{Λ max.} For example, in order to exhibit an antireflection effect for all wavelengths in the visible light band, d _AVG ≦ 380 nm may be set, and d _max = d _AVG + 2σ _d ≦ 380 nm is preferable. A preferable condition that can more reliably exhibit the antireflection effect for all wavelengths in the visible light band is d _AVG ≦ 300 nm, a more preferable condition is d _max ≦ 300 nm, and a still more preferable condition is d _AVG ≦ 200 nm. There is a particularly preferred condition of d _max ≦ 200 nm. Moreover, d _AVG ≧ 50 nm is usually satisfied and d _AVG ≧ 100 nm is preferable because of the manifestation of the antireflection effect and ensuring the isotropic (low angle dependency) of the reflectance. The projections for the height H, in order to exhibit a sufficient anti-reflection effect, the shortest wavelength in the wavelength band of light to improve the antireflection when a lambda _max, the H _AVG ≧ 0.2 × Λ _max it is preferred, is preferably _{H AVG} ≧ 0.2 × 780nm = _156nm in order to can achieve an antireflection effect for all wavelengths of visible light _band, it is more preferably a _{H AVG} ≧ 170 nm. The height _{HAVG of the} protrusion is usually 350 nm or less from the viewpoint of the antireflection effect. Further, the height distribution of the protrusions is usually 50 to 350 nm.

The aspect ratio (average protrusion height H _AVG / average adjacent protrusion interval d _AVG ) of the fine protrusions can be set to 0.8 to 5.0, and in particular, 0.8 to 2.5 from the viewpoint of antireflection performance. Preferably, it is more preferable that it is 1.0-2.1.

  The thickness of the fine uneven layer (T in FIG. 1) may be adjusted as appropriate, but is preferably 3 μm to 30 μm, and more preferably 5 μm to 10 μm. In the present invention, the thickness T of the fine concavo-convex layer is defined as the thickness from the interface of the fine concavo-convex layer to the transparent base material to the top of the highest minute protrusion.

<Transparent substrate>
The antireflection article according to the present invention may include a transparent substrate as a support. The transparent base material used for this invention can be suitably selected and used according to a use from the well-known transparent base materials used for an antireflection article. Specific examples of materials used for the transparent substrate include acetyl cellulose resins such as triacetyl cellulose, polyester resins such as polyethylene terephthalate and polyethylene naphthalate, olefin resins such as polyethylene and polymethylpentene, acrylic resins, Transparent resins such as polyurethane resin, polyethersulfone, polycarbonate, polysulfone, polyether, polyetherketone, acrylonitrile, methacrylonitrile, cycloolefin polymer, cycloolefin copolymer, glass such as soda glass, potassium glass, lead glass And transparent inorganic materials such as ceramics such as lead lanthanum zirconate titanate (PLZT), quartz, and fluorite.

  The transparent substrate preferably has a transmittance in the visible light region of 80% or more, and more preferably 90% or more. Here, the transmittance | permeability of a transparent base material can be measured by JISK7361-1 (the test method of the total light transmittance of a plastic-transparent material).

  Although the thickness of the said transparent base material can be suitably set according to the use of the antireflective article of this invention, Although it does not specifically limit, Usually, it is 20-5000 micrometers, The said transparent base material is supplied with the form of a roll. However, it may be any one of those that do not bend to the extent that they can be wound, but that can be bent by applying a load, or those that do not bend completely.

The configuration of the transparent substrate used in the present invention is not limited to a configuration consisting of a single layer, and may have a configuration in which a plurality of layers are laminated. When it has the structure by which the several layer was laminated | stacked, the layer of the same composition may be laminated | stacked, and the several layer which has a different composition may be laminated | stacked.
Moreover, you may form the primer layer for improving the adhesiveness of a transparent base material and the said fine uneven | corrugated layer, and, thereby improving abrasion resistance (scratch resistance) on a transparent base material. This primer layer preferably has adhesiveness to the transparent substrate and the fine uneven layer adjacent to the transparent substrate via the primer layer and transmits visible light.

<Other layers>
The antireflection article of the present invention may further have other layers as long as the effects of the present invention are not impaired. The surface side of the transparent substrate that does not have the fine uneven layer may have various conventionally known layers used for optical film applications. For example, a conventionally known single layer or multilayer antireflection layer, a layer imparting antiglare property (or antireflection) by light diffusion, a conventionally known hard coat layer for preventing scratches, and the like can be mentioned.

  In the antireflection article according to the present invention, a peelable protective film may be temporarily bonded to the surface of the fine uneven layer 2 on the fine uneven shape side. Thus, the protective film is temporarily bonded to the surface of the fine concavo-convex shape layer 2, and the antireflection article according to the present invention is stored, transported, bought and sold, post-processed or constructed, and the protective film is used in a timely manner. Therefore, it is possible to prevent damage and contamination of the surface of the fine unevenness side of the fine unevenness layer 3 during storage, transportation, and the like.

  In the antireflection article of the present invention, the transmittance in the visible light region is preferably 80% or more, and more preferably 90% or more. Here, the transmittance of the antireflective article can be measured by JIS K7361-1 (a test method for the total light transmittance of plastic-transparent material).

<Use of anti-reflective article>
The antireflection article according to the present invention can be used for various articles in addition to the image display device described later.
For example, shop windows, exhibition windows for museum exhibits; display windows for clocks and other measuring instruments; various printed materials such as road signs and posters; vehicles such as automobiles and aircraft; and windows for various buildings Visibility can be improved by arranging it on the front surface or both surfaces. It can also be used as a window material for various optical devices such as glasses, cameras, telescopes, microscopes, and various illumination devices.

In the above-described embodiment, the wavelength band of the electromagnetic wave for preventing reflection has been described as the visible light band, but the present invention is not limited to this, and the wavelength band of the electromagnetic wave for preventing reflection is infrared, ultraviolet, or the like. The wavelength band other than visible light may be set. In that case, in each of the above conditional expressions, the shortest wavelength Λ _min and the longest wavelength Λ _max of the wavelength band of the electromagnetic wave are respectively set to the shortest wavelength and the longest wavelength for which an antireflection effect is desired in the wavelength band of infrared rays, ultraviolet rays, etc. It is sufficient to set each. For example, when it is desired to prevent reflection in the infrared band where the shortest wavelength Λ _min is 850 nm, the distance d between adjacent protrusions (or its average value d _AVG ) may be designed to be 850 nm or less, for example, d _AVG = 800 nm.

<Method for producing antireflection article>
What is necessary is just to select the manufacturing method of the antireflection article of this invention suitably from the conventionally well-known method of forming the fine uneven | corrugated layer which has fine uneven | corrugated shape on the surface.
For example, first, a resin composition for forming a fine concavo-convex layer is applied onto a transparent substrate, and the concavo-convex shape of the original substrate for forming a fine concavo-convex layer having a desired fine concavo-convex shape is formed into a coating film of the resin composition. Thereafter, the resin composition is cured to form a fine concavo-convex layer, and then peeled off from the fine concavo-convex layer forming original plate. The method for curing the resin composition can be appropriately selected according to the type of the resin composition.

The master for forming the fine uneven layer is not particularly limited as long as it is not deformed and worn when repeatedly used, and may be made of metal or resin, Metal is preferably used. This is because it is excellent in deformation resistance and wear resistance.
The surface having the fine concavo-convex shape of the original plate for forming the fine concavo-convex layer is not particularly limited, but is preferably made of aluminum from the viewpoint of being easily oxidized and easily processed by anodization.
Specifically, the master for forming the fine uneven layer is, for example, a high-purity aluminum by sputtering or the like directly on the surface of a metal base material such as stainless steel, copper, or aluminum, or through various intermediate layers. A layer is provided, and the aluminum layer is formed with an uneven shape. Prior to providing the aluminum layer, the surface of the base material may be made into a super mirror surface by an electrolytic composite polishing method in which electrolytic elution action and abrasion action by abrasive grains are combined.
As a method of forming a fine uneven shape on the original plate for forming a fine uneven layer, for example, an anodic oxidation step of forming a plurality of fine holes on the surface of the aluminum layer by an anodic oxidation method, and etching the aluminum layer A first etching step for forming a tapered shape in the opening of the microhole, and a second for enlarging the hole diameter of the microhole by etching the aluminum layer at an etching rate higher than the etching rate of the first etching step. It can be formed by sequentially repeating the etching process.
When forming a fine concavo-convex shape, a desired shape can be obtained by appropriately adjusting the purity (amount of impurities), crystal grain size, anodizing treatment and / or etching conditions of the aluminum layer. . In the anodizing treatment, more specifically, by controlling the liquid temperature, the voltage to be applied, the time for the anodizing, etc., fine holes are formed into shapes corresponding to the target depth and the shape of the fine protrusions, respectively. be able to.
In this way, in the original plate for forming a fine concavo-convex layer, a large number of fine holes whose pore diameter gradually decreases in the depth direction are densely produced. In the fine concavo-convex layer manufactured using the fine concavo-convex layer forming original plate, fine concavo-convex portions having a small protrusion group that gradually decreases in diameter as it approaches the top corresponding to the fine holes are formed. The cross-sectional area occupancy rate of the material portion forming the fine unevenness in the horizontal cross section when it is assumed to be cut in a horizontal plane perpendicular to the depth direction of the fine unevenness approaches the deepest portion direction from the top of the fine unevenness. As a result, a fine concavo-convex shape that gradually increases gradually is formed.

Further, the shape of the original plate for forming a fine uneven layer is not particularly limited as long as it can shape a desired shape. For example, it may be a flat plate shape or a roll shape. However, it is preferable to use a roll-shaped mold (hereinafter sometimes referred to as a “roll mold”) from the viewpoint of improving productivity.
As a roll mold used in the present invention, for example, as a base material, a cylindrical metal material is used, and an aluminum layer provided directly or via various intermediate layers on the peripheral side surface of the base material, As described above, there may be mentioned those in which fine irregularities are produced by repeating anodizing treatment and etching treatment.

In FIG. 4, when a photocurable resin composition is used as the resin composition for forming the fine uneven layer and a roll mold is used as the original plate for forming the fine uneven layer, the fine uneven layer is formed on the transparent substrate. An example of the method is shown.
In the method shown in FIG. 4, in the resin supplying step, an uncured and liquid photocurable resin composition is applied to the transparent base material 1 in the form of a strip with a die 11 to form a microprojection-shaped receiving layer 2 ′. To do. In addition, about application | coating of a photocurable resin composition, not only the case by the die | dye 11 but various methods are applicable. Subsequently, the pressing roller 13 presses and presses the transparent base material 1 against the peripheral side surface of the roll mold 12 which is a master for forming a fine uneven layer, thereby bringing the receiving layer 2 ′ into close contact with the transparent base material 1, A fine concavo-convex recess formed on the peripheral side surface of the roll mold 12 is sufficiently filled with the photocurable resin composition constituting the receiving layer 2 ′. In this state, the photocurable resin composition is cured by irradiation with ultraviolet rays, whereby the fine uneven layer 2 is produced on the surface of the transparent substrate 1. Subsequently, the transparent substrate 1 is peeled off from the roll die 12 through the peeling roller 14 together with the hardened fine uneven structure 2. If necessary, an adhesive layer or the like is produced on the transparent substrate 1 and then cut to a desired size to produce the antireflection article 1. As a result, the anti-reflective article is formed by sequentially molding the fine concavo-convex shape produced on the peripheral side surface of the roll mold 12 which is the original plate for forming the fine concavo-convex layer on the long transparent base material 1 made of a roll material, and efficiently. Mass production.

In the above-described embodiment, the case where a film-shaped antireflection article is produced by a forming process using a roll mold is described. However, the present invention is not limited to this, and the transparent substrate according to the shape of the antireflection article is used. Depending on the shape of the material, for example, when making a sheet-shaped antireflection article by a shaping process using a flat plate, a master for forming a fine uneven layer with a specific curved surface, etc. The layer forming original plate can be appropriately changed according to the shape of the transparent substrate according to the shape of the antireflection article.
Further, in the antireflection article according to the present invention, the transparent substrate used in the production may be peeled off as necessary to provide only a fine uneven layer, or a transparent substrate as a resin composition for the fine uneven layer. By using the same material as that described above, the fine uneven layer and the transparent substrate may be integrated.

[Image display device]
The image display device according to the present invention includes the antireflection article according to the present invention on at least one side of a display panel.
In the antireflection article according to the present invention provided on at least one surface side of the display panel, the image display device of the present invention is capable of wiping off dirt adhering to the surface, and can suppress a decrease in antireflection performance, and Since it has excellent scratch resistance, it has excellent antifouling properties, antireflection properties, and scratch resistance. The image display apparatus according to the present invention can be suitably used particularly as an apparatus that often directly touches the surface of the display apparatus with a finger, for example, an image display apparatus provided with a touch panel member.

As shown in FIG. 5, the image display device 20 of the present invention includes the antireflection article 10 according to the present invention on at least one surface side of the display panel 4. The antireflection article 10 may be directly bonded to the display panel 4, and has another member between the antireflection article 10 and the display panel 4 as long as the effects of the present invention are not impaired. Also good. As said other member, a well-known touch panel member etc. are mentioned, for example.
The image display device of the present invention may be a device having only a display function (for example, an LCD monitor, a CRT monitor, etc.), but a device having a display function as a part of the function of the device is also applicable. For example, a portable information terminal, a car navigation system, or the like.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits the same effects. Are included in the technical scope.

(Production Example 1: Production of master plate 1 for forming a fine uneven layer)
A rolled aluminum plate having a purity of 99.50% is polished so that its surface has an irregular shape with a 10-point average roughness Rz of 30 nm and a period of 1 μm, and then formed in an electrolyte solution of 0.02 M oxalic acid aqueous solution. Anodization was performed for 120 seconds under conditions of a voltage of 60 V and 20 ° C. Next, as a first etching process, an etching process was performed for 60 seconds with the electrolytic solution after anodization. Subsequently, as the second etching treatment, a pore size treatment was performed with a 1.0 M phosphoric acid aqueous solution for 150 seconds. Furthermore, the said process was repeated and these were added and implemented 5 times in total. As a result, an anodized aluminum layer having fine irregularities formed on the aluminum substrate was formed. Finally, a fluorine-based mold release agent was applied and the excess mold release agent was washed to obtain an original plate for forming a fine uneven layer. The fine uneven shape formed in the aluminum layer was a shape in which an average distance between adjacent micropores _dAVG was 150 nm and a large number of micropores gradually decreasing in the depth direction. .

(Production Example 2: Preparation of resin composition A for fine uneven layer)
The following components were mixed, and a resin composition A for fine uneven layer having a solid content of 45% by mass was prepared using methyl ethyl ketone and methyl isobutyl ketone as diluent solvents.
<Composition of resin composition A for fine uneven layer>
-Ethylene oxide modified (EO modified) bisphenol A diacrylate 55 parts by mass-EO modified trimethylolpropane triacrylate 25 parts by mass-Polyrotaxane (SA3405P, manufactured by Advanced Soft Materials Co., Ltd.) Functionality containing an ethylenically unsaturated bond in the cyclic molecule 20 parts by mass having a group) 1 part by mass of diphenyl (2,4,6-trimethoxybenzoyl) phosphine oxide (Lucirin TPO)

(Production Example 3: Preparation of resin composition B for fine uneven layer)
The following components were mixed, and a resin composition B for a fine uneven layer having a solid content of 45% by mass was prepared using methyl ethyl ketone and methyl isobutyl ketone as diluent solvents.
<Composition of resin composition B for fine uneven layer>
-Ethylene oxide modified (EO modified) bisphenol A diacrylate 55 parts by mass-EO modified trimethylolpropane triacrylate 25 parts by mass-Polyrotaxane (SA3405P, Advanced Soft Materials Co., Ltd.); 10 parts by mass having a group) 1 part by mass of diphenyl (2,4,6-trimethoxybenzoyl) phosphine oxide (Lucirin TPO)

(Production Example 4: Preparation of resin composition C for fine uneven layer)
The following components were mixed, and a resin composition C for a fine uneven layer having a solid content of 45% by mass was prepared using methyl ethyl ketone and methyl isobutyl ketone as diluent solvents.
<Composition of resin composition C for fine uneven layer>
-Ethylene oxide modified (EO modified) bisphenol A diacrylate 55 parts by mass-EO modified trimethylolpropane triacrylate 25 parts by mass-Diphenyl (2,4,6-trimethoxybenzoyl) phosphine oxide (Lucirin TPO) 1 part by mass

(Production Example 5: Preparation of resin composition D for fine uneven layer)
The following components were mixed, and a resin composition D for a fine uneven layer having a solid content of 45% by mass was prepared using methyl ethyl ketone and methyl isobutyl ketone as diluent solvents.
<Composition of resin composition D for fine uneven layer>
-Ethylene oxide-modified (EO-modified) bisphenol A diacrylate 50 parts by mass-Trimethylolpropane triacrylate 30 parts by mass-Polyrotaxane (manufactured by Advanced Soft Materials, Inc. SA3405P; a functional group containing an ethylenically unsaturated bond in the cyclic molecule 20 parts by mass of diphenyl (2,4,6-trimethoxybenzoyl) phosphine oxide (Lucirin TPO) 1 part by mass

(Production Example 6: Preparation of resin composition E for fine uneven layer)
The following components were mixed, and a resin composition E for fine concavo-convex layer having a solid content of 45 mass% was prepared using methyl ethyl ketone and methyl isobutyl ketone as diluent solvents.
<Composition of resin composition E for fine uneven layer>
・ Ethylene oxide-modified (EO-modified) bisphenol A diacrylate 50 parts by mass ・ Trimethylolpropane triacrylate 30 parts by mass ・ Diphenyl (2,4,6-trimethoxybenzoyl) phosphine oxide (Lucirin TPO) 1 part by mass

[Example 1]
As the resin composition for forming a fine concavo-convex layer, the resin composition A for forming a fine concavo-convex layer is coated with the fine concavo-convex surface of the fine concavo-convex layer forming original plate 1 obtained above, and the thickness of the fine concavo-convex layer after curing Is applied and filled so that the thickness becomes 20 μm, and a 80 μm-thick triacetyl cellulose film (TAC) (manufactured by Fuji Film Co., Ltd.) is bonded obliquely thereon as a transparent substrate, and then the bonded body is bonded. Was pressed with a rubber roller under a load of 10 N / cm ² . After confirming that the uniform composition was applied to the entire original plate, ultraviolet rays were irradiated from the transparent substrate side with an energy of 2000 mJ / cm ² to cure the resin composition for forming a fine uneven layer. Then, it peeled from the original plate and obtained the antireflection article of Example 1. The resulting fine projection group provided in the fine uneven layer of the antireflective article is the average adjacent projections spacing _{d AVG} is 150 nm (standard deviation sigma _d 10 nm), an average height _{H AVG} is 240 nm, the aspect ratio _{(H AVG} / D _AVG ) was 1.6.

[Example 2]
In the same production procedure as in Example 1, except that the resin composition B for forming a fine uneven layer was used instead of the resin composition A for forming a fine uneven layer as the resin composition for forming the fine uneven layer. Two antireflective articles were obtained.

[Example 3]
In the same production procedure as Example 1, except that the resin composition D for forming a fine uneven layer was used instead of the resin composition A for forming a fine uneven layer as the resin composition for forming the fine uneven layer. 3 antireflective articles were obtained.

[Comparative Example 1]
Comparative Example 1 was carried out in the same production procedure as Example 1, except that the resin composition C for forming a fine uneven layer was used instead of the resin composition A for forming a fine uneven layer as the resin composition for forming a fine uneven layer. An antireflective article was obtained.

[Comparative Example 2]
Comparative Example 2 in the same production procedure as Example 1 except that the resin composition E for forming a fine uneven layer was used instead of the resin composition A for forming a fine uneven layer as the resin composition for forming a fine uneven layer. An antireflective article was obtained.

[Evaluation]
<Measurement of storage elastic modulus (E ')>
The resin compositions A to E for fine concavo-convex layers obtained in Production Examples 2 to 6 are each sufficiently cured by irradiating ultraviolet rays having an energy of 2000 mJ / cm ² for 1 minute to have a substrate and fine concavo-convex shapes. A test single membrane having a thickness of 1 mm, a width of 5 mm, and a length of 30 mm was obtained.
Next, in accordance with JIS K7244, by applying a periodic external force of 25 g at 25 Hz at 10 Hz in the length direction of the cured product of the resin composition, and measuring the dynamic viscoelasticity, the storage elasticity at 25 ° C. The modulus E ′ and the loss elastic modulus E ″ were obtained. Further, tan δ (E ″ / E ′) was calculated from the results of E ′ and E ″. The measuring apparatus used was RBM Ogel made by UBM. Table 1 shows.

<Abrasion resistance test>
The anti-reflective articles obtained in Examples 1 to 3 and Comparative Examples 1 and 2 were evaluated for the scratch resistance of each article by evaluating steel wool resistance.
That is, first, steel wool # 0000 (manufactured by Bonster Pound) is attached to a steel wool resistance evaluation jig having a tip diameter of φ11.3 mm, and then the evaluation surface (fine uneven surface) of the article faces upward. The sample was placed on a glass plate, and the four sides were taped, taking care not to enter air. Using the steel wool resistant jig adjusted to a weight of 100 g, the sample surface was rubbed while being slid laterally so as to make 10 reciprocations at the same speed at a scanning speed of 20 to 30 mm / sec. Black tape was affixed to the side opposite to the evaluated sample surface, the number of scratches rubbed on the sample surface was observed and counted using a three-wavelength tube, and the scratch resistance of the article was evaluated according to the following evaluation criteria. The evaluation results are shown in Table 1.
(Evaluation criteria)
A: No scratch B: 1 to 5 scratches C: 5 scratches exceeded

<Wipeability test>
The surface of the anti-reflective article obtained in Examples 1 to 3 and Comparative Examples 1 and 2 is attached to a black acrylic plate with an adhesive layer, with the surface on the fine uneven surface side, and then the finger is pressed to attach the fingerprint. It was. Thereafter, the fingerprint was wiped dry with Zavina Minimax (Fuji Chemical). Dry wiping was performed 10 times with a force of about 3 kg / cm ² , and the appearance after wiping was evaluated. The evaluation results are shown in Table 1.
(Evaluation criteria)
A: Fingerprint stains are not visible.
B: Fingerprints are hardly wiped off.

<Visibility (clouding) test>
The anti-reflective articles obtained in Examples 1 to 3 and Comparative Examples 1 and 2 were attached to a black acrylic plate with an adhesive layer, with the surface of the anti-reflective article side as the upper surface. ) Was rubbed 10 times with a force of about 3 kg / cm ² . The visibility after 1 minute of rubbing was evaluated according to the following criteria. The evaluation results are shown in Table 1.
(Evaluation criteria)
A: Scratch marks are not visually recognized.
B: Scratch marks are clearly cloudy or change in color.

(Summary of results)
Since the anti-reflective article obtained in Examples 1 to 3 was made of a cured product of a resin composition containing a polyrotaxane, the fine uneven layer was excellent in scratch resistance and could wipe off dirt adhering to the surface. However, even when rubbed, no scratch marks were produced, and the deterioration of the antireflection performance was suppressed, and all of the scratch resistance, dirt wiping property and antireflection performance were excellent.
On the other hand, the antireflective article obtained in Comparative Example 1 was inferior in scratch resistance because the resin composition used for forming the fine uneven layer did not contain polyrotaxane, and thus was poor in resilience. , It became cloudy after rubbing.
The antireflective article obtained in Comparative Example 2 was hard and brittle and inferior in scratch resistance, difficult to deform, and inferior in dirt wiping because the resin composition used for forming the fine concavo-convex layer did not contain polyrotaxane. It was.

DESCRIPTION OF SYMBOLS 1 Transparent base material 2 Fine uneven | corrugated layer 2a Fine uneven | corrugated surface 2b Enveloping surface 2 'which connected the valley bottom between each microprotrusion 2' Receptive layer 3 Microprotrusion 4 Display panel 10 Antireflection article 11 Die 12 Roll die 13 Press roller 14 Peeling roller 20 Image display device

Claims (4)

An anti-reflective article having a fine concavo-convex shape having a micro-protrusion group having a plurality of micro-protrusions arranged in close contact with each other, and having a fine concavo-convex layer made of a cured resin composition
When the shortest wavelength of the wavelength band of light for preventing reflection is Λ _min and the average value of the adjacent protrusion intervals d of the fine protrusions is d _AVG ,
d _AVG ≦ Λ _min
Have the relationship
The storage elastic modulus (E ′) at 25 ° C. of the cured product of the resin composition is 300 MPa or less,
An antireflection article, wherein the resin composition contains a polyrotaxane.   The antireflection article according to claim 1, wherein the polyrotaxane has a functional group containing an ethylenically unsaturated bond in a cyclic molecule.   The antireflection article according to claim 1 or 2, wherein the content of the polyrotaxane is 0.5 to 30.0 mass% with respect to the total solid content contained in the resin composition.   An image display device comprising the antireflection article according to any one of claims 1 to 3 on at least one surface side of the display panel.