JP2013215918A - Laminate and article having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate which has a reflection prevention function, has favorable adhesiveness to a base material, and can easily be peeled off if intentionally peeled off even if used for a long period of time, and an article having the same.SOLUTION: A laminate 14 has a film 16 having a fine irregular structure at one surface and a pressure sensitive adhesive layer 18 laminated on the other surface of the film 16, and is adhered on the base material 12 via the pressure sensitive adhesive layer 18. In the laminate 14, the pressure sensitive adhesive layer 18 is composed of a pressure sensitive adhesive which is peelable from the base material 12 while maintaining adhesion to the base material 12 after a lapse of 500 hours under an atmosphere of a temperature of 60°C and humidity of 90% RH.

Description

  The present invention relates to a laminate and an article having the same.

  In recent years, it has been known that an article having a fine concavo-convex structure with a period equal to or shorter than the wavelength of visible light on the surface exhibits an antireflection effect, a lotus effect, and the like. In particular, it is known that a fine concavo-convex structure called a moth-eye structure is an effective antireflection means by continuously increasing the refractive index from the refractive index of air to the refractive index of the material of the article. .

An article having a fine concavo-convex structure on the surface can be obtained, for example, by sticking a film having a fine concavo-convex structure on the surface to an article main body (base material) so that the surface on which the fine concavo-convex structure is not formed is in contact. . Adhesives such as transparent adhesives and double-sided adhesive tapes are often used for attaching films and substrates. Alternatively, a pressure-sensitive adhesive layer may be provided on the surface where the fine uneven structure of the film is not formed, and the film may be attached to the substrate via the pressure-sensitive adhesive layer.
As a film having a fine concavo-convex structure on the surface, for example, Patent Document 1 discloses an antireflection article having a fine concavo-convex structure formed on the surface by a transfer method using anodized alumina as a stamper. Patent Document 2 discloses a laminate having fine irregularities on one side of a film and provided with an adhesive layer on the opposite side.

JP 2009-109572 A JP 2011-26449 A

  Articles that have a film with a fine concavo-convex structure on the surface are attached to the surface of the base material via an adhesive, and the base material is used after the film is removed from the base material and replaced with a new film or the film is peeled off. Sometimes. However, at the initial stage of attaching the film to the base material, the film can be easily peeled off. However, if the film is attached to the base material for a long time, the adhesive deteriorates or the adhesive is applied to the base material. Or even if the film is intentionally peeled off, it may be difficult to peel off from the substrate.

  The present invention has been made in view of the above circumstances, and has an antireflection function, has good adhesion to a substrate, and is intentionally peeled off even if it has been adhered for a long time. It is an object of the present invention to provide a laminate that can be easily peeled off, and an article having the laminate.

The laminate of the present invention comprises a film having a fine concavo-convex structure formed on one surface and a pressure-sensitive adhesive layer laminated on the other surface of the film, and is stuck on a substrate via the pressure-sensitive adhesive layer. The pressure-sensitive adhesive layer is peelable from the base material while maintaining the sticking to the base material after 500 hours have passed in an atmosphere of a temperature of 60 ° C. and a humidity of 90% RH. It is characterized by comprising an adhesive.
Moreover, it is preferable that the said adhesive layer consists of an adhesive which does not whiten even if it sticks on a base material using water or aqueous solution.
Furthermore, it is preferable that the said adhesive layer consists of an adhesive which does not contain a carboxyl group, has a water absorption of 0.01 to 3%, and has a gel fraction of 10 to 100%.
Moreover, the article of the present invention is characterized by having a base material and the above-mentioned laminate adhered to the base material via an adhesive layer.

  According to the present invention, the laminate has an antireflection function, has a good sticking property to a substrate, and can be easily peeled off if intentionally peeled off even if stuck for a long time. And articles having the same.

It is sectional drawing which shows an example of the articles | goods of this invention. It is sectional drawing which shows an example of the film with which the laminated body of this invention is equipped. It is a block diagram which shows an example of the manufacturing apparatus of the film with which the laminated body of this invention is equipped. It is sectional drawing which shows the manufacturing process of the mold which has an anodized alumina on the surface.

  In this specification, “(meth) acrylate” is a general term for acrylate and methacrylate, and “(meth) acrylic acid” is a general term for acrylic acid and methacrylic acid. “Active energy rays” mean visible light, ultraviolet rays, electron beams, plasma, heat rays (infrared rays, etc.) and the like.

  FIG. 1 is a cross-sectional view showing an example of the article of the present invention. The article 10 of this example has a base material 12 and a laminate 14 of the present invention attached on the base material 12.

<Base material>
Although it does not restrict | limit especially as the base material 12, For example, a glass plate, a resin board (Acrylic resin, vinyl chloride resin, polypropylene, polycarbonate, acrylonitrile butadiene styrene (ABS) resin, polyethylene terephthalate (PET) resin, triacetyl cellulose resin Etc.).
Although the kind of the base material 12 is determined according to a use, when using a base material as a member used for front plates, such as an image display apparatus, an acrylic resin board is preferable, for example.

<Laminated body>
The laminate 14 of the present invention includes a film 16 having a fine concavo-convex structure (not shown) formed on one surface, and an adhesive layer 18 laminated on the other surface of the film 16.
The laminate 14 is stuck on the substrate 12 via the pressure-sensitive adhesive layer 18.

(Adhesive layer)
The pressure-sensitive adhesive layer 18 maintains adhesion to the base material 12 after 500 hours have passed in an atmosphere of a temperature of 60 ° C. and a humidity of 90% RH (hereinafter sometimes referred to as “after durability”), It consists of an adhesive that can be peeled off from the substrate 12.
Here, “can be peeled off from the base material while maintaining sticking to the base material” means that the article 10 is intentionally peeled off after being left for 500 hours in an atmosphere of a temperature of 60 ° C. and a humidity of 90% RH. If there is not, the laminated body 14 is stuck without peeling off from the base material 12, but if it is intentionally peeled off, it means that the laminated body 14 is easily peeled off from the base material 12. Specifically, it means that the peel strength with respect to the substrate 12 after durability is in the range of 2 to 40 N / 25 mm, and preferably in the range of 5 to 30 N / 25 mm.
In addition, the peeling strength of an adhesive layer is measured based on JISZ0237.

Moreover, although mentioned later in detail, when sticking the laminated body 14 to the base material 12, although an adhesive layer 18 or the sticking surface of the base material 12 may apply water or aqueous solution, an adhesive layer 18 is preferably made of a pressure-sensitive adhesive that does not whiten even when pasted on the substrate 12 using water or an aqueous solution. If the pressure-sensitive adhesive layer 18 is made of such a pressure-sensitive adhesive, the pressure-sensitive adhesive layer 18 will not be whitened even if the laminate 14 is attached to the substrate 12 using water or an aqueous solution, so that the design and transparency are good. Can be maintained.
Here, “do not whiten” means that whitening is not visually confirmed, and means that, for example, the total light transmittance is 80% or more.

After 500 hours have passed in an atmosphere of a temperature of 60 ° C. and a humidity of 90% RH, it can be peeled off from the base material 12 while maintaining the sticking to the base material 12, and on the base material 12 using water or an aqueous solution. As the pressure-sensitive adhesive that does not whiten even if it is attached to the film, a pressure-sensitive adhesive that does not contain a carboxyl group, has a water absorption of 0.01 to 3%, and a gel fraction of 10 to 100% is preferable.
By using a pressure-sensitive adhesive that does not contain a carboxyl group, it is possible to suppress an increase in pressure-sensitive adhesive strength over time after application. As a result, the peelability after endurance becomes good, and the laminate that can be easily peeled off if it is intentionally peeled off even if it is stuck on the base material 12 for a long time while maintaining the sticking to the base material 12 A body 14 is obtained.
Here, “not containing a carboxyl group” means not containing a polymer or copolymer obtained by polymerizing or copolymerizing a monomer having a carboxyl group, as will be described in detail later.

By using a pressure-sensitive adhesive having a water absorption rate of 0.01 to 3%, swelling of the pressure-sensitive adhesive due to water can be suppressed. As a result, it is possible to suppress the whitening or swelling of the pressure-sensitive adhesive layer 18 after sticking the laminate 14 to the base material 12 using water or an aqueous solution, and maintaining durability, thus maintaining the design and transparency. it can. The water absorption is preferably 0.1 to 2%.
Here, the water absorption is determined as follows.
First, an adhesive layer is laminated | stacked so that thickness may be set to 1 mm. Specifically, a pressure-sensitive adhesive is applied on the release film to form a pressure-sensitive adhesive layer, the operation of laminating the pressure-sensitive adhesive layers and peeling the release film is repeated, and the pressure-sensitive adhesive layer is laminated until the thickness becomes 1 mm. To do. The mass (G ₁ ) of the test piece (i) cut out from this laminate to a size of 30 mm × 30 mm is measured. Next, the test piece (i) was allowed to stand for 24 hours in an atmosphere at a temperature of 60 ° C. and a humidity of 90% RH, and the mass (G ₂ ) of the test piece (i) immediately after being left was measured. Obtain the water absorption rate of the agent.
Water absorption rate (%) = {(G ₂ −G ₁ ) / G ₁ } × 100 (i)

Moreover, the fluidity | liquidity of an adhesive can be suppressed by using the adhesive whose gel fraction is 10% or more. As a result, it is possible to suppress foaming of the pressure-sensitive adhesive layer 18 after durability by using a pressure-sensitive adhesive having a gel fraction of 10 to 100%, so that designability and transparency can be maintained. In addition, since the lifting and peeling of the pressure-sensitive adhesive layer 18 after the endurance can be suppressed, the sticking property can be maintained even after the endurance unless it is intentionally peeled off. The gel fraction is preferably 30 to 90%.
Here, the gel fraction is determined as follows.
First, an adhesive is apply | coated on a peeling film and an adhesive layer is formed. A release film is further laminated on the pressure-sensitive adhesive layer and cut into a size of 50 mm × 90 mm. Remove the release film on both sides of the cut piece and measure the mass of the test piece (ii) in which the adhesive layer is wrapped with a polytetrafluoroethylene mesh (# 380). The mass (G ₃ ) of the agent layer is determined. Next, the test piece (ii) is immersed in 200 mL of ethyl acetate for 48 hours and then dried at 80 ° C. for 2 hours. The mass of the test piece (ii) after drying is measured, the mass of the pressure-sensitive adhesive layer (G ₄ ) is obtained by subtracting the mass of the mesh from the measured value, and the gel fraction of the pressure-sensitive adhesive is obtained from the following formula (ii).
Gel fraction (%) = (G ₄ / G ₃ ) × 100 (ii)

The pressure-sensitive adhesive containing no carboxyl group preferably contains a (meth) acrylic acid ester copolymer obtained by copolymerizing a monomer having no carboxyl group.
As such a (meth) acrylic acid ester-based copolymer, a (meth) acrylic acid alkyl ester having no carboxyl group and having 1 to 20 carbon atoms in the ester moiety (hereinafter referred to as “single amount”). Body (a1) "), a monomer having no carboxyl group and having a crosslinkable functional group in the molecule (hereinafter referred to as" monomer (a2) "), and optionally used. And a copolymer obtained by copolymerizing a monomer mixture containing another monomer (hereinafter referred to as “monomer (a3)”).

Examples of the monomer (a1) include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, and (meth) acrylic acid. Hexyl, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, myristyl (meth) acrylate, (meth) acrylic Examples include palmitic acid and stearyl (meth) acrylate. These may be used alone or in combination of two or more.
The ratio of the monomer (a1) is preferably 30 to 99.9% by mass in 100% by mass of the monomer mixture constituting the (meth) acrylic acid ester copolymer.

As the monomer (a2), a monomer containing at least one of a hydroxyl group, an amino group, and an amide group as a crosslinkable functional group is preferable. Specifically, 2-hydroxyethyl (meth) acrylate, (meth) Such as 2-hydroxypropyl acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, ) Acrylic acid hydroxyalkyl ester; (Meth) acrylamides such as (meth) acrylamide, N-methyl (meth) acrylamide, N-methylol (meth) acrylamide; (meth) acrylic acid monomethylaminoethyl, (meth) acrylic acid mono Ethylaminoethyl, (meth) acrylic acid monomethylaminopropyl, (meth ) (Meth) monoalkylamino esters of acrylic acid such as acrylic acid monoethyl aminopropyl; dimethylaminoethyl (meth) acrylate, and (meth) such as diethylaminoethyl acrylate ethyl (meth) acrylic acid dialkyl amino ester. These may be used alone or in combination of two or more.
The proportion of the monomer (a2) is preferably 0.1 to 20% by mass in 100% by mass of the monomer mixture constituting the (meth) acrylic acid ester copolymer.

  The monomer (a3) is not particularly limited as long as it does not have a carboxyl group and can be copolymerized with the monomer (a1) and the monomer (a2) described above. , Α-methylstyrene, vinyl toluene, vinyl formate, vinyl acetate, acrylonitrile and the like.

  There is no restriction | limiting in particular about the copolymerization form of a (meth) acrylic acid ester type copolymer, Any of a random, a block, and a graft copolymer may be sufficient.

The (meth) acrylic acid ester copolymer preferably has a mass average molecular weight of 300,000 to 2,000,000. In particular, if the mass average molecular weight is 300,000 or more, the heat resistance of the pressure-sensitive adhesive layer 18 is improved, and the pressure-sensitive adhesive layer 18 can be prevented from foaming or peeling even when the article 10 is exposed to high temperature conditions.
The mass average molecular weight is a value in terms of polystyrene measured by a gel permeation chromatography (GPC) method.

  The (meth) acrylic acid ester copolymer may be used alone or in combination (blended) with two or more. Furthermore, you may use together the polymer ((meth) acrylic acid ester type polymer) which polymerized the monomer (a1) mentioned above, the monomer (a2), and the monomer (a3) independently.

The pressure-sensitive adhesive used in the present invention may contain a crosslinking agent.
There is no restriction | limiting in particular as a crosslinking agent, Arbitrary things can be suitably selected and used from what was conventionally used as a crosslinking agent in an acrylic adhesive. Examples of such a cross-linking agent include polyisocyanate compounds, epoxy resins, melamine resins, urea resins, dialdehydes, methylol polymers, aziridine compounds, metal chelate compounds, metal alkoxides, and metal salts.
As for content of a crosslinking agent, 0.1-15 mass parts is preferable with respect to 100 mass parts of solid content of a (meth) acrylic acid ester type copolymer.

  Furthermore, the pressure-sensitive adhesive can contain additives such as a silane coupling agent, a rust inhibitor, a coloring matter, and a pigment as necessary.

The water absorption and gel fraction of the pressure-sensitive adhesive can be adjusted by the type and ratio (content) of the monomer constituting the (meth) acrylic acid ester copolymer, the content of the crosslinking agent, and the like.
Specifically, when the proportion of the monomer (a1) or the proportion of the monomer (a2) constituting the (meth) acrylic acid ester copolymer is reduced, the water absorption of the pressure-sensitive adhesive The rate tends to be high. Conversely, when the proportion of the monomer (a1) increases or the proportion of the monomer (a2) decreases, the water absorption rate of the pressure-sensitive adhesive tends to decrease.
Moreover, when the content of the crosslinking agent increases, the gel fraction of the pressure-sensitive adhesive tends to increase. On the other hand, when the content of the crosslinking agent decreases, the gel fraction of the pressure-sensitive adhesive tends to be low.

  As for the thickness of the adhesive layer 18, 5-100 micrometers is preferable. If the thickness of the pressure-sensitive adhesive layer 18 is 5 μm or more, the pressure-sensitive adhesive layer 18 easily follows the surface shape of the substrate 12, so that sufficient adhesion is obtained and the sticking property of the laminate 14 is improved. improves. On the other hand, if the thickness of the pressure-sensitive adhesive layer 18 is 100 μm or less, the ratio of the residual solvent amount contained in the pressure-sensitive adhesive can be reduced, and the pressure-sensitive adhesive layer 18 foams even when the article 10 is exposed to high temperature conditions. Can be suppressed.

(the film)
The film 16 shown in FIG. 1 has a film body 16a and a cured resin film 16b formed on the surface of the film body 16a.
The film body 16a is a film having optical transparency. Examples of the material for the film body 16a include acrylic resins, polycarbonates, styrene resins, polyesters, cellulose resins (such as triacetyl cellulose), polyolefins, and alicyclic polyolefins. Among them, the film 16 is preferably an acrylic resin.

The cured resin film 16b is a light-transmitting film made of a cured product of an active energy ray-curable resin composition described later, and has a plurality of convex portions 19 on the surface, for example, as shown in FIG.
The protrusion 19 is preferably formed by transferring a plurality of pores (recesses) on the surface of anodized alumina.

  The plurality of convex portions 19 preferably form a so-called moth-eye structure in which a plurality of protrusions (convex portions) having a substantially conical shape or a pyramid shape are arranged at intervals equal to or shorter than the wavelength of visible light. It is known that the moth-eye structure becomes an effective antireflection means by continuously increasing the refractive index from the refractive index of air to the refractive index of the material.

The average period between the convex portions 19 is preferably not more than the wavelength of visible light, that is, not more than 400 nm, more preferably not more than 200 nm, and particularly preferably not more than 150 nm. Here, the average period between the convex portions 19 means that the cross section of the cured resin film 16b is observed with an electron microscope, and the interval P between the adjacent convex portions 19 (from the center of the convex portion 19 to the center of the adjacent convex portion 19). ) Is measured at 50 points, and these values are averaged.
In addition, when the convex part 19 is formed using the mold of the anodic oxidation alumina mentioned later, the average period between the convex parts 19 becomes about 100 nm, and is preferable.

The height H of the convex part 19 is preferably 100 to 500 nm, and more preferably 130 to 400 nm. If the height H of the convex portion 19 is 100 nm or more, the reflectance is sufficiently low and the wavelength dependence of the reflectance is small. If the height H of the convex part 19 is 500 nm or less, the mechanical strength of the convex part 19 will be favorable.
As for the width W of the bottom part of the convex part 19, 100-500 nm is preferable.

H and W can be measured by observing the cross section of the cured resin film 16b with an electron microscope.
W is a width in the same plane (hereinafter referred to as a reference plane) as the bottom of the concave portion formed around the convex portion 19.
H is the height from the reference surface to the top of the convex portion 19.

  H and W are conditions for producing a mold having anodized alumina on the surface, and the viscosity of the active energy ray-curable resin composition filled in the pores (recesses) of the mold (see Japanese Patent Application Laid-Open No. 2008-197216). It can adjust by selecting etc. suitably.

  When the surface has a moth-eye structure, if the surface is made of a hydrophobic material, super water repellency can be obtained by the lotus effect, and if the surface is made of a hydrophilic material, super hydrophilicity can be obtained. It is known.

  When the material of the cured resin film 16b is hydrophobic, the water contact angle on the surface of the moth-eye structure is preferably 90 ° or more, more preferably 100 ° or more, and particularly preferably 110 ° or more. If the water contact angle is 90 ° or more, water stains are less likely to adhere, so that sufficient antifouling properties are exhibited. Moreover, since water does not adhere easily, anti-icing can be expected.

  When the material of the cured resin film 16b is hydrophilic, the water contact angle of the surface of the moth-eye structure is preferably 25 ° or less, more preferably 23 ° or less, and particularly preferably 21 ° or less. If the water contact angle is 25 ° or less, the dirt adhering to the surface is washed away with water and oil dirt is less likely to adhere, so that sufficient antifouling properties are exhibited. The water contact angle is preferably 3 ° or more from the viewpoint of suppressing deformation of the moth-eye structure due to water absorption of the cured resin film 16b and the accompanying increase in reflectance.

(Film production method)
The film 16 is manufactured as follows using, for example, a manufacturing apparatus shown in FIG.
Between the surface of the roll-shaped mold 22 having a reverse microstructure composed of a plurality of concave portions (not shown) corresponding to the plurality of convex portions on the surface, and the strip-shaped film main body 16a moving along the surface of the mold 22 The active energy ray-curable resin composition 21 is supplied from the tank 24.

  The film main body 16a and the active energy ray curable resin composition 21 are nipped between the mold 22 and the nip roll 28 whose nip pressure is adjusted by the pneumatic cylinder 26, and the active energy ray curable resin composition 21 is removed from the film. The main body 16a and the mold 22 are uniformly distributed, and at the same time, the concave portions of the mold 22 are filled.

The active energy ray curable resin composition 21 is sandwiched between the mold 22 and the film body 16a, and the active energy ray irradiation device 30 installed below the mold 22 is used to activate the film body 16a from the film body 16a side. By irradiating the energy ray curable resin composition 21 with active energy rays and curing the active energy ray curable resin composition 21, a cured resin film 16b to which a plurality of recesses on the surface of the mold 22 is transferred is formed. .
The film 16 is obtained by peeling the film body 16 a having the cured resin film 16 b formed on the surface by the peeling roll 32.

As a light source used for the active energy ray irradiation apparatus 30, for example, a high-pressure mercury lamp, a metal halide lamp, a fusion UV lamp or the like is preferable. In this case, the amount of light irradiation energy is preferably 100 to 10,000 mJ / cm ² .

(mold)
The mold 22 has a reversal structure (hereinafter referred to as a reversal fine concavo-convex structure) corresponding to the fine concavo-convex structure on the surface of the finally obtained film on the surface of the mold body.

Examples of the material for the mold main body include metals (including those having an oxide film formed on the surface), quartz, glass, resin, ceramics, and the like.
Examples of the shape of the mold body include a roll shape, a circular tube shape, a flat plate shape, and a sheet shape.

Examples of the mold production method include the following methods (X) and (Y). The method (X) is preferable because the mold can have a large area and can be easily produced.
(X) A method of forming anodized alumina having a plurality of pores (concave portions) on the surface of a mold body made of aluminum.
(Y) A method of directly forming a fine concavo-convex structure on the surface of a mold body by lithography, electron beam drawing, laser light interference, or the like.

As the method (X), a method having the following steps (a) to (e) is preferable.
(A) A step of forming an oxide film by anodizing aluminum in an electrolytic solution under a constant voltage.
(B) A step of removing the oxide film and forming pore generation points for anodic oxidation.
(C) A step of anodizing aluminum again in an electrolytic solution to form an oxide film having pores at the pore generation points.
(D) A step of enlarging the diameter of the pores.
(E) A step of repeatedly performing the steps (c) and (d).

Step (a):
As shown in FIG. 4, when the aluminum 34 is anodized, an oxide film 38 having pores 36 is formed.
Examples of the electrolytic solution include oxalic acid and sulfuric acid.

When using oxalic acid as electrolyte:
The concentration of oxalic acid is preferably 0.7 M or less. When the concentration of oxalic acid exceeds 0.7M, the current value becomes too high, and the surface of the oxide film may become rough.
When the formation voltage is 30 to 60 V, anodized alumina having highly regular pores with a period of 100 nm can be obtained. Regardless of whether the formation voltage is higher or lower than this range, the regularity tends to decrease.
The temperature of the electrolytic solution is preferably 60 ° C. or lower, and more preferably 45 ° C. or lower. When the temperature of the electrolytic solution exceeds 60 ° C., a so-called “burn” phenomenon occurs, and the pores may be broken, or the surface may melt and the regularity of the pores may be disturbed.

When using sulfuric acid as the electrolyte:
The concentration of sulfuric acid is preferably 0.7M or less. If the concentration of sulfuric acid exceeds 0.7M, the current value may become too high to maintain a constant voltage.
When the formation voltage is 25 to 30 V, anodized alumina having highly regular pores with a period of 63 nm can be obtained. The regularity tends to decrease whether the formation voltage is higher or lower than this range.
The temperature of the electrolytic solution is preferably 30 ° C. or lower, and more preferably 20 ° C. or lower. When the temperature of the electrolytic solution exceeds 30 ° C., a so-called “burn” phenomenon occurs, and the pores may be broken or the surface may melt and the regularity of the pores may be disturbed.

Step (b):
As shown in FIG. 4, the regularity of the pores can be improved by once removing the oxide film 38 and using it as the pore generation point 40 for anodic oxidation.

  Examples of the method for removing the oxide film include a method in which aluminum is not dissolved but is dissolved in a solution that selectively dissolves the oxide film and removed. Examples of such a solution include a chromic acid / phosphoric acid mixed solution.

Step (c):
As shown in FIG. 4, when the aluminum 34 from which the oxide film has been removed is anodized again, an oxide film 38 having cylindrical pores 36 is formed.
Anodization may be performed under the same conditions as in step (a). Deeper pores can be obtained as the anodic oxidation time is lengthened.

Step (d):
As shown in FIG. 4, a process for expanding the diameter of the pores 36 (hereinafter referred to as a pore diameter expanding process) is performed. The pore diameter expansion treatment is a treatment for expanding the diameter of the pores obtained by anodic oxidation by immersing in a solution dissolving the oxide film. Examples of such a solution include a phosphoric acid aqueous solution of about 5% by mass.
The longer the pore diameter expansion processing time, the larger the pore diameter.

Step (e):
As shown in FIG. 4, when the anodic oxidation in the step (c) and the pore diameter enlargement process in the step (d) are repeated, the pores 36 have a shape in which the diameter continuously decreases in the depth direction from the opening. An anodized alumina (a porous oxide film of aluminum (alumite)) is formed, and a mold 22 having an inverted fine uneven structure on the surface is obtained.
The total number of repetitions is preferably 3 times or more, and more preferably 5 times or more. When the number of repetitions is 2 times or less, the diameter of the pores decreases discontinuously. Therefore, the effect of reducing the reflectance of the cured resin film produced using the anodized alumina having such pores is insufficient. .

Examples of the shape of the pores 36 include a substantially conical shape and a pyramid shape.
The average period between the pores 36 is not more than the wavelength of visible light, that is, not more than 400 nm. The average period between the pores 36 is preferably 25 nm or more.

The depth of the pores 36 is preferably 100 to 500 nm, and more preferably 150 to 400 nm.
The surface of the cured resin film 16b formed by transferring the pores 36 as shown in FIG. 4 has a so-called moth-eye structure.

  The surface of the mold 22 may be treated with a release agent so as to facilitate separation from the cured resin film. Examples of the release agent include silicone resins, fluororesins, and fluorine compounds.

(Active energy ray-curable resin composition)
The active energy ray-curable resin composition contains a polymerizable compound and a polymerization initiator.
As an active energy ray-curable resin composition, when an acrylic film is used as a film body, the difference between the refractive index of the film body and the refractive index of the cured resin film is sufficiently small, so that an acrylic monomer (single amount) The body) is preferred.

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

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

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

  Examples of the monomer having a cationic polymerizable bond include monomers having an epoxy group, an oxetanyl group, an oxazolyl group, a vinyloxy group, and the like, and a monomer having an epoxy group is particularly preferable.

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

Examples of non-reactive polymers include acrylic resins, styrene resins, polyurethanes, cellulose resins, polyvinyl butyral, polyesters, thermoplastic elastomers, and the like.
Examples of the active energy ray sol-gel reactive composition include alkoxysilane compounds and alkyl silicate compounds.

As an alkoxysilane compound, the compound of following formula (1) is mentioned.
R ¹ _x Si (OR ² ) _y (1)
^However, R 1, ^{R 2} each represent an alkyl group having 1 to 10 carbon atoms, x, y represents an integer satisfying the relation of x + y = 4.

  Examples of the alkoxysilane compound include tetramethoxysilane, tetra-i-propoxysilane, tetra-n-propoxysilane, tetra-n-butoxysilane, tetra-sec-butoxysilane, tetra-t-butoxysilane, methyltriethoxysilane, Examples include methyltripropoxysilane, methyltributoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, trimethylethoxysilane, trimethylmethoxysilane, trimethylpropoxysilane, and trimethylbutoxysilane.

Examples of the alkyl silicate compound include a compound of the following formula (2).
R ³ O [Si (OR ⁵ ) (OR ⁶ ) O] _z R ⁴ (2)
However, R < ³ > -R < ⁶ > represents a C1-C5 alkyl group, respectively, and z represents the integer of 3-20.

  Examples of the alkyl silicate compound include methyl silicate, ethyl silicate, isopropyl silicate, n-propyl silicate, n-butyl silicate, n-pentyl silicate, acetyl silicate and the like.

When utilizing photocuring reaction, a radical polymerization initiator is mentioned as a photoinitiator.
The radical polymerization initiator is not particularly limited as long as it generates a radical upon irradiation with a known active energy ray, and specifically includes an acetophenone-based photopolymerization initiator, a benzoin-based photopolymerization initiator, and a benzophenone-based initiator. Examples include photopolymerization initiators, thioxanthone photopolymerization initiators, and acylphosphine oxide photopolymerization initiators.
Examples of the acetophenone photopolymerization initiator include acetophenone, p- (tert-butyl) -1 ′, 1 ′, 1′-trichloroacetophenone, chloroacetophenone, 2 ′, 2′-diethoxyacetophenone, hydroxyacetophenone, 2, Examples include 2-dimethoxy-2′-phenylacetophenone, 2-aminoacetophenone, and dialkylaminoacetophenone.
Examples of the benzoin photopolymerization initiator include benzyl, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-2 -Methylpropan-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, benzyldimethyl ketal and the like.
Examples of the benzophenone photopolymerization initiator include benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, methyl-o-benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, hydroxypropylbenzophenone, acrylic benzophenone, and 4,4′-bis. And (dimethylamino) benzophenone.
Examples of the thioxanthone photopolymerization initiator include thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, diethylthioxanthone, and dimethylthioxanthone.
Examples of the acylphosphine oxide photopolymerization initiator include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, benzoyldiethoxyphosphine oxide, and bis2,4,6-trimethylbenzoylphenylphosphine oxide. .
Examples of other radical polymerization initiators include α-acyl oxime ester, benzyl- (o-ethoxycarbonyl) -α-monooxime, glyoxy ester, 3-ketocoumarin, 2-ethylanthraquinone, camphorquinone, and tetramethyl. Examples include thiuram sulfide, azobisisobutyronitrile, benzoyl peroxide, dialkyl peroxide, and tert-butyl peroxypivalate.
These radical polymerization initiators may be used alone or in combination of two or more.

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

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

  The active energy ray-curable resin composition may contain an antistatic agent, a release agent, an additive such as a fluorine compound for improving antifouling properties, fine particles, and a small amount of a solvent, if necessary. .

(Hydrophobic material)
In order to set the water contact angle of the surface of the moth-eye structure of the cured resin film to 90 ° or more, the composition containing a fluorine-containing compound or a silicone compound as an active energy ray-curable resin composition capable of forming a hydrophobic material It is preferable to use a product.

Fluorine-containing compounds:
As the fluorine-containing compound, a compound having a fluoroalkyl group represented by the following formula (3) is preferable.
_{- (CF 2) n -X ···} (3)
However, X represents a fluorine atom or a hydrogen atom, n represents an integer greater than or equal to 1, 1-20 are preferable, 3-10 are more preferable, and 4-8 are especially preferable.

  Examples of the fluorine-containing compound include a fluorine-containing monomer, a fluorine-containing silane coupling agent, a fluorine-containing surfactant, and a fluorine-containing polymer.

Examples of the fluorine-containing monomer include a fluoroalkyl group-substituted vinyl monomer and a fluoroalkyl group-substituted ring-opening polymerizable monomer.
Examples of the fluoroalkyl group-substituted vinyl monomer include fluoroalkyl group-substituted (meth) acrylates, fluoroalkyl group-substituted (meth) acrylamides, fluoroalkyl group-substituted vinyl ethers, and fluoroalkyl group-substituted styrenes.

  Examples of the fluoroalkyl group-substituted ring-opening polymerizable monomer include fluoroalkyl group-substituted epoxy compounds, fluoroalkyl group-substituted oxetane compounds, and fluoroalkyl group-substituted oxazoline compounds.

As the fluorine-containing monomer, a fluoroalkyl group-substituted (meth) acrylate is preferable, and a compound of the following formula (4) is particularly preferable.
^{_{CH 2 = C (R 7)}} C (O) O- (CH 2) m - (CF 2) p -X ··· (4)
However, R ⁷ represents a hydrogen atom or a methyl group, X represents a hydrogen atom or a fluorine atom, m represents an integer of 1 to 6, preferably 1 to 3, more preferably 1 or 2, p Represents an integer of 1 to 20, preferably 3 to 10, and more preferably 4 to 8.

As the fluorine-containing silane coupling agent, a fluoroalkyl group-substituted silane coupling agent is preferable, and a compound of the following formula (5) is particularly preferable.
(R ^f ) _a R ⁸ _b SiY _c (5)

R ^f represents a C1-C20 fluorine-substituted alkyl group which may contain one or more ether bonds or ester bonds. Examples of R ^f include 3,3,3-trifluoropropyl group, tridecafluoro-1,1,2,2-tetrahydrooctyl group, 3-trifluoromethoxypropyl group, 3-trifluoroacetoxypropyl group and the like. It is done.

R ⁸ represents an alkyl group having 1 to 10 carbon atoms. Examples of R ⁸ include a methyl group, an ethyl group, and a cyclohexyl group.

Y represents a hydroxyl group or a hydrolyzable group.
Examples of the hydrolyzable group include an alkoxy group, a halogen atom, R ⁹ C (O) O (wherein R ⁹ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms) and the like.
Examples of the alkoxy group include methoxy group, ethoxy group, propyloxy group, i-propyloxy group, butoxy group, i-butoxy group, t-butoxy group, pentyloxy group, hexyloxy group, cyclohexyloxy group, heptyloxy group, Examples include octyloxy group, 2-ethylhexyloxy group, nonyloxy group, decyloxy group, 3,7-dimethyloctyloxy group, lauryloxy group, and the like.
Examples of the halogen atom include Cl, Br, I and the like.
Examples of R ⁹ C (O) O include CH ₃ C (O) O, C ₂ H ₅ C (O) O, and the like.

  a, b, and c are integers satisfying a + b + c = 4 and satisfying a ≧ 1, c ≧ 1, and preferably a = 1, b = 0, and c = 3.

  Fluorine-containing silane coupling agents include 3,3,3-trifluoropropyltrimethoxysilane, 3,3,3-trifluoropropyltriacetoxysilane, dimethyl-3,3,3-trifluoropropylmethoxysilane, tri Examples include decafluoro-1,1,2,2-tetrahydrooctyltriethoxysilane.

  Examples of the fluorine-containing surfactant include a fluoroalkyl group-containing anionic surfactant and a fluoroalkyl group-containing cationic surfactant.

Examples of the fluoroalkyl group-containing anionic surfactant include a fluoroalkylcarboxylic acid having 2 to 10 carbon atoms or a metal salt thereof, disodium perfluorooctanesulfonyl glutamate, 3- [omega-fluoroalkyl (C ₆ -C ₁₁ ) oxy. ] -1-alkyl _(C 3 _{~C 4)} sulfonate, sodium 3- [omega - fluoroalkanoyl _{(C 6 ~C} 8) -N- ethylamino] -1-sodium sulfonic acid, fluoroalkyl _{(C 11} ~ C ₂₀ ) carboxylic acid or a metal salt thereof, perfluoroalkyl carboxylic acid (C _{7 to} C ₁₃ ) or a metal salt thereof, perfluoroalkyl (C _{4 to} C ₁₂ ) sulfonic acid or a metal salt thereof, perfluorooctane sulfonic acid diethanolamine N-propyl-N- (2-hydroxy Chill) perfluorooctane sulfonamide, perfluoroalkyl _(C 6 _{-C 10)} sulfonamide propyl trimethyl ammonium salts, perfluoroalkyl _{(C 6} -C 10)-N-ethylsulfonyl glycine salts, monoperfluoroalkyl _{(C 6} -C ₁₆₎ ethyl phosphoric acid ester, and the like.

Examples of the fluoroalkyl group-containing cationic surfactant include aliphatic quaternary compounds such as fluoroalkyl group-containing aliphatic primary, secondary or tertiary amine acids, and perfluoroalkyl (C ₆ -C ₁₀ ) sulfonamidopropyltrimethylammonium salts. Examples thereof include ammonium salts, benzalkonium salts, benzethonium chloride, pyridinium salts, imidazolinium salts, and the like.

  Fluorine-containing polymers include polymers of fluoroalkyl group-containing monomers, copolymers of fluoroalkyl group-containing monomers and poly (oxyalkylene) group-containing monomers, and copolymers of fluoroalkyl group-containing monomers and crosslinking reactive group-containing monomers. A polymer etc. are mentioned. The fluorine-containing polymer may be a copolymer with another copolymerizable monomer.

As the fluorine-containing polymer, a copolymer of a fluoroalkyl group-containing monomer and a poly (oxyalkylene) group-containing monomer is preferable.
As the poly (oxyalkylene) group, a group represented by the following formula (6) is preferable.
− (OR ¹⁰ ) _q − (6)
^{However, R 10} represents an alkylene group having 2 to 4 carbon atoms, q represents an integer of 2 or more.
Examples of R ¹⁰ include —CH ₂ CH ₂ —, —CH ₂ CH ₂ CH ₂ —, —CH (CH ₃ ) CH ₂ —, —CH (CH ₃ ) CH (CH ₃ ) —, and the like.

The poly (oxyalkylene) group may be composed of the same oxyalkylene unit (OR ¹⁰ ), or may be composed of two or more oxyalkylene units (OR ¹⁰ ). The arrangement of two or more oxyalkylene units (OR ¹⁰ ) may be a block or random.

Silicone compounds:
Examples of the silicone compound include (meth) acrylic acid-modified silicone, silicone resin, silicone silane coupling agent and the like.
Examples of the (meth) acrylic acid-modified silicone include silicone (di) (meth) acrylate.

(Hydrophilic material)
In order to reduce the water contact angle of the surface of the moth-eye structure of the cured resin film to 25 ° or less, an active energy ray-curable resin composition capable of forming a hydrophilic material is used as a polyfunctional (meth) acrylate having 4 or more functionalities. It is preferable to use a composition containing a bifunctional or higher hydrophilic (meth) acrylate and a monofunctional monomer. By including a tetrafunctional or higher polyfunctional (meth) acrylate, the scratch resistance is improved, and by including a bifunctional or higher hydrophilic (meth) acrylate, the hydrophilicity is sufficient and the antifouling property is improved. The monofunctional monomer also acts as a viscosity modifier, an adhesion improver for the substrate, and the like.

Examples of tetrafunctional or higher polyfunctional (meth) acrylates include ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol ethoxytetra (meth) acrylate, dipentaerythritol hydroxypenta (meth) acrylate, di Pentaerythritol hexa (meth) acrylate, succinic acid / trimethylolethane / acrylic acid molar mixture 1: 2: 4 condensation reaction mixture, urethane acrylates (manufactured by Daicel-Cytec: EBECRYL220, EBECRYL1290K, EBECRYL1290K, EBECRYL5129, EBECRYL8210, EBECRYL 8301, KRM 8200), polyether acrylates (manufactured by Daicel-Cytec: EBEC) YL81), modified epoxy acrylates (manufactured by Daicel-Cytec: EBECRYL3416), polyester acrylates (manufactured by Daicel-Cytech: EBECRYL450, EBECRYL657, EBECRYL800, EBECRYL810, EBECRYL8111, EBECRYL81L, EBECRYL81L It is done. These may be used alone or in combination of two or more.
The polyfunctional (meth) acrylate having 4 or more functional groups is more preferably a polyfunctional (meth) acrylate having 5 or more functional groups.

Long-chain polyethylene such as Aronix M-240, Aronix M260 (manufactured by Toagosei Co., Ltd.), NK ester AT-20E, NK ester ATM-35E (manufactured by Shin-Nakamura Chemical Co., Ltd.) Examples thereof include polyfunctional acrylates having glycol and polyethylene glycol dimethacrylate. These may be used alone or in combination of two or more.
In the polyethylene glycol dimethacrylate, the total of the average repeating units of the polyethylene glycol chain present in one molecule is preferably 6 to 40, more preferably 9 to 30, and particularly preferably 12 to 20. If the average repeating unit of the polyethylene glycol chain is 6 or more, the hydrophilicity is sufficient and the antifouling property is improved. When the average repeating unit of the polyethylene glycol chain is 40 or less, the compatibility with a polyfunctional (meth) acrylate having 4 or more functionalities is improved, and the active energy ray-curable resin composition is hardly separated.

As the monofunctional monomer, a hydrophilic monofunctional monomer is preferable.
Examples of the hydrophilic monofunctional monomer include monofunctional (meth) acrylate having a polyethylene glycol chain in the ester group such as M-20G, M-90G, M-230G (manufactured by Shin-Nakamura Chemical Co., Ltd.), hydroxyalkyl (meth) acrylate, etc. And cationic monomers such as monofunctional (meth) acrylates having a hydroxyl group in the ester group, monofunctional acrylamides, methacrylamidopropyltrimethylammonium methyl sulfate, and methacryloyloxyethyltrimethylammonium methyl sulfate.
Moreover, as a monofunctional monomer, you may use viscosity modifiers, such as acryloyl morpholine and vinyl pyrrolidone, adhesive improvement agents, such as acryloyl isocyanate which improves the adhesiveness to a base material, etc.

  The monofunctional monomer may be blended in the active energy ray-curable resin composition in an amount of 0 to 35 parts by mass as a polymer having a low polymerization degree obtained by (co) polymerizing one type or two or more types. As a polymer having a low degree of polymerization, 40/60 of monofunctional (meth) acrylates having a polyethylene glycol chain in an ester group such as M-230G (manufactured by Shin-Nakamura Chemical Co., Ltd.) and methacrylamide propyltrimethylammonium methyl sulfate. Copolymer oligomer (MRC Unitech Co., Ltd., MG polymer) and the like can be mentioned.

<Method for producing laminate>
The laminate 14 of the present invention is formed by applying and drying a pressure-sensitive adhesive coating liquid constituting the pressure-sensitive adhesive layer 18 to a predetermined thickness on the release film, and forming the pressure-sensitive adhesive layer 18 on the fine uneven structure of the film 16. It is obtained by transferring to the surface on the side where is not formed.

As the release film, a sheet in which a release agent layer is formed by coating a release agent such as a fluororesin, a silicone resin, or a long chain alkyl group-containing carbamate on the surface of a release sheet substrate such as a resin film is used. .
As the release film substrate, a resin film such as a polyester such as polyethylene terephthalate, a polyolefin such as polyethylene, polypropylene, or polybutadiene can be used.
Although the thickness of the base material for peeling films changes with materials to be used, it is about 10-100 micrometers normally.

In order to form the pressure-sensitive adhesive layer on the release film, the following may be performed.
That is, a pressure-sensitive adhesive coating solution is prepared, and the coating solution is applied onto a release film. Thereafter, in order to prevent the solvent and low-boiling components from remaining, the temperature is about 60 to 150 ° C. for about 30 seconds to 5 minutes. By drying by heating, adhesiveness is developed and a pressure-sensitive adhesive layer is formed.
Although it does not restrict | limit especially as a solvent used for the coating liquid of an adhesive, For example, methyl ethyl ketone etc. are mentioned.
As a method for applying the adhesive coating solution onto the release film, a conventional method such as a gravure coating method, a bar coating method, a spray coating method, a spin coating method, a roll coating method, a die coating method, or a knife coating method is used. An air knife coating method, a hot melt coating method, a curtain coating method, or the like can be used.

The obtained laminated body 14 may be stuck on the base material 12 through the pressure-sensitive adhesive layer 18 as it is, or may be temporarily wound around a roll or the like and stored. When storing, the release film or the like is further stacked on the pressure-sensitive adhesive layer 18.
The laminate 14 is coated on the film 16 by applying and drying the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 18 on the surface of the film 16 where the fine concavo-convex structure is not formed. It can also be obtained by laminating the agent layer 18.

Since the laminated body of the present invention described above includes a film having a fine concavo-convex structure formed on the surface, an excellent antireflection function can be exhibited.
Moreover, since the laminated body of this invention is equipped with the adhesive layer, it has favorable sticking property with respect to a base material. This pressure-sensitive adhesive layer is made of a pressure-sensitive adhesive that can be peeled off from the base material while maintaining its sticking to the base material after the endurance. If it is going to peel off, a laminated body can be peeled easily. The fact that the laminate can be easily peeled means that the adhesive does not easily transfer to the substrate, so there is little adhesive residue on the substrate, and the design of the substrate is maintained well even after the laminate is peeled off. it can.

In addition, when the pressure-sensitive adhesive layer is made of a pressure-sensitive adhesive that does not whiten even when pasted on a substrate using water or an aqueous solution, the laminate may be stuck on the substrate using water or an aqueous solution. Since the pressure-sensitive adhesive layer is hardly whitened, the designability and transparency can be maintained well.
In particular, the pressure-sensitive adhesive that does not contain a carboxyl group, has a water absorption rate of 0.01 to 3%, and a gel fraction of 10 to 100% maintains the adhesion to the base material after durability, It can be peeled from the material and does not whiten even if it is attached to a substrate using water or an aqueous solution. In addition, since it also has durability, if this adhesive is used, it can suppress that an adhesive layer whitens or foams after durability. Moreover, since the floating and peeling of the pressure-sensitive adhesive layer after durability can be suppressed, the sticking property can be maintained even after durability unless it is intentionally peeled off.

  In addition, the laminated body of this invention is not limited to the laminated body 14 of the example of illustration. For example, in the laminate 14, the plurality of convex portions 19 are formed on the surface of the cured resin film 16 b of the film 16, but are directly formed on the surface of the film body 16 a without providing the cured resin film 16 b. Also good. However, a plurality of protrusions 19 are formed on the surface of the cured resin film 16b of the film 16 as shown in FIG. 2 because the plurality of protrusions 19 can be efficiently formed using the roll-shaped mold 22. Is preferred.

<Production method>
The article of the present invention can be obtained by sticking the above-described laminate of the present invention onto a substrate via the pressure-sensitive adhesive layer of the laminate.
When the peeling film is laminated | stacked on the adhesive layer of a laminated body, a peeling film is peeled from a laminated body, the surface of an adhesive layer is exposed, and it affixes on a base material.
When adhering the laminate to the substrate, the adhesive layer of the laminate may be adhered to the substrate directly, or water or an aqueous solution (such as detergent water) may be adhered to the adhesive layer or substrate. The pressure-sensitive adhesive layer may be brought into contact with the substrate after being applied to the sticking surface. By using water or an aqueous solution when adhering the laminate to the substrate, it becomes easier to adjust the position at which the laminate is applied to the substrate.

  As described above, the article of the present invention has an antireflection function, has a good sticking property to the base material, and can be easily peeled off intentionally even if it is stuck for a long time. Since it has a laminate that can be peeled off, it has an antireflection function, and the laminate can be easily replaced (exchanged), and the design can be maintained well.

  The article of the present invention can be suitably used for a member that requires an antireflection function. If the article of the present invention is used, it is difficult to reflect sunlight, illumination light, etc., and thus visibility can be maintained.

  Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited thereto.

(Pores of anodized alumina)
Part of the anodized alumina is shaved, platinum is deposited on the cross section for 1 minute, and the cross section is subjected to acceleration voltage: 3.00 kV using a field emission scanning electron microscope (JSM-7400F, manufactured by JEOL Ltd.). Observed and measured pore spacing and pore depth. Each measurement was performed for 50 points, and the average value was obtained.

(Convex part of cured resin film)
Platinum is vapor-deposited on the fracture surface of the cured resin film for 5 minutes, and the cross-section is observed using a field emission scanning electron microscope (JSM-7400F, JSM-7400F) under an acceleration voltage of 3.00 kV. The average interval between the parts and the height of the convex part were measured. Each measurement was performed for 50 points, and the average value was obtained.

(Water absorption of adhesive)
The pressure-sensitive adhesive coating solution used in Examples and Comparative Examples was applied to the release-treated surface of a release film (manufactured by Lintec Corporation, “SP-PET381031C”) and dried at 90 ° C. for 60 seconds to form an adhesive layer. The operation of laminating the pressure-sensitive adhesive layers and peeling off the release film was repeated, and the pressure-sensitive adhesive layer was laminated until the thickness became 1 mm. The mass (G ₁ ) of the test piece (i) cut out from the laminate to a size of 30 mm × 30 mm was measured. Next, the test piece (i) was allowed to stand for 24 hours in an atmosphere at a temperature of 60 ° C. and a humidity of 90% RH, and the mass (G ₂ ) of the test piece (i) immediately after being left was measured. The water absorption rate of the agent was determined.
Water absorption rate (%) = {(G ₂ −G ₁ ) / G ₁ } × 100 (i)

(Gel fraction of adhesive)
The pressure-sensitive adhesive coating solution used in Examples and Comparative Examples was applied to the release-treated surface of a release film (manufactured by Lintec Corporation, “SP-PET381031C”) and dried at 90 ° C. for 60 seconds to form an adhesive layer. On the pressure-sensitive adhesive layer, a release film (“SP-PET382120” manufactured by Lintec Corporation) was laminated so that the release-treated surface was in contact with the pressure-sensitive adhesive layer, and cut into a size of 50 mm × 90 mm. Remove the release film on both sides of the cut piece and measure the mass of the test piece (ii) in which the adhesive layer is wrapped with a polytetrafluoroethylene mesh (# 380). The mass (G ₃ ) of the agent layer was determined. Next, the test piece (ii) was immersed in 200 mL of ethyl acetate for 48 hours and then dried at 80 ° C. for 2 hours. The mass of the dried test piece (ii) was measured, the mass of the pressure-sensitive adhesive layer (G ₄ ) was determined by subtracting the mass of the mesh from the measured value, and the gel fraction of the pressure-sensitive adhesive was determined from the following formula (ii). .
Gel fraction (%) = (G ₄ / G ₃ ) × 100 (ii)

(Transmittance of film)
The release film of the laminate having a fine concavo-convex structure formed on one surface was peeled to expose the adhesive layer, and an acrylic resin plate (Mitsubishi Rayon Co., Ltd., “Acrylite L # 001”, 50 mm × 60 mm size) Adhering to one surface, using a haze meter (manufactured by Suga Test Instruments Co., Ltd.), measuring the total light transmittance of the surface of the cured resin film (the surface on which the fine concavo-convex structure is formed) according to JIS K7361-1. did.

(Film reflectivity)
The reflectance of the film was determined by peeling the release film of the laminate having a fine concavo-convex structure formed on one surface to expose the adhesive layer, and using a black acrylic resin plate (“Acrylite EX # 502, manufactured by Mitsubishi Rayon Co., Ltd.). ”, 50 mm × 60 mm size), using a spectrophotometer (manufactured by Hitachi, Ltd., U-4000), incident angle: 5 ° (using 5 ° specular reflection accessory), wavelength range of 380 to 780 nm The relative reflectance of the surface of the cured resin film (the surface on which the fine concavo-convex structure was formed) was measured, and the visibility reflectance was calculated according to JIS R3106.

(Peeling and whitening after durability)
The test pieces (iii) produced in the examples and comparative examples were left for 24 hours in an atmosphere of a temperature of 23 ° C. and a humidity of 50% RH.
Subsequently, it was further left for 500 hours in an atmosphere of a temperature of 60 ° C. and a humidity of 90% RH.
For the test piece (iii) after standing, the presence or absence of peeling or whitening of the pressure-sensitive adhesive layer was visually confirmed. If no peeling or whitening was observed, “○”, and if peeling or whitening was observed, “×” ”, A case where only peeling was observed was designated as“ × (peeled) ”, and a case where only whitening was observed was designated as“ x (white) ”.

(Removability after endurance)
The test pieces (iii) produced in the examples and comparative examples were left for 24 hours in an atmosphere of a temperature of 23 ° C. and a humidity of 50% RH.
Subsequently, it was further left for 500 hours in an atmosphere of a temperature of 60 ° C. and a humidity of 90% RH.
Regarding the test piece (iii) after standing, “○” indicates that the laminate is peeled off from the glass plate by hand and can be peeled off (that is, the laminate can be completely peeled off from the glass plate). The case where a part or all of was left on the glass plate was defined as “x”.

(Whitening and swelling after sticking)
The test pieces (iii) produced in the examples and comparative examples were left for 24 hours in an atmosphere of a temperature of 23 ° C. and a humidity of 50% RH.
About the test piece (iii) after leaving, the presence or absence of whitening and swelling of the pressure-sensitive adhesive layer was visually confirmed. When no whitening and swelling were observed, “○”, and when whitening and swelling were observed, “×” ”,“ × (white) ”when only whitening was observed, and“ × (swollen) ”when only swelling was observed.

(Manufacturing method of mold a)
After applying a blanket polishing treatment to an aluminum ingot having a diameter of 200 mm and a length of 350 mm cut from a 99.99% pure aluminum ingot, a rubbing treatment was applied to the aluminum ingot in a perchloric acid / ethanol mixed solution (volume Ratio: 1/4) was electropolished and mirror finished.

Step (a):
The aluminum prototype was anodized in a 0.3 M oxalic acid aqueous solution under the conditions of DC: 40 V and temperature: 16 ° C. for 30 minutes.
Step (b):
The aluminum original mold on which the oxide film having a thickness of 3 μm was formed was immersed in a 6% by mass phosphoric acid / 1.8% by mass chromic acid mixed aqueous solution to remove the oxide film.
Step (c):
The aluminum prototype was anodized in a 0.3 M oxalic acid aqueous solution for 30 seconds under the conditions of DC: 40 V and temperature: 16 ° C.
Step (d):
The aluminum prototype on which the oxide film was formed was immersed in a 5% by mass phosphoric acid aqueous solution at 30 ° C. for 8 minutes to carry out pore size expansion treatment.
Step (e):
The step (c) and the step (d) are repeated 5 times in total, and a roll-shaped mold a having anodized alumina having substantially conical pores with an average period of 100 nm and a depth of 200 nm formed on the surface is obtained. Obtained.

  The mold a was dipped in a 0.1% by mass diluted solution of OPTOOL DSX (manufactured by Daikin Chemicals Sales) for 10 minutes at room temperature and pulled up. The mold a treated with a release agent was obtained by air drying overnight.

(Preparation of active energy ray-curable resin composition)
An active energy ray-curable resin composition A (Table 1) having the following composition was prepared.

[Example 1]
<Manufacture of film>
The film was manufactured using the manufacturing apparatus shown in FIG.
As the roll-shaped mold 22, the mold a was used.
As the active energy ray curable resin composition 21, the active energy ray curable resin composition A was used.
As the film body 16a, an acrylic film having a roughened surface was used.
From the film body 16a side, an ultraviolet ray having an integrated light amount of 800 mJ / cm ² is applied to the coating film of the active energy ray curable resin composition A to cure the active energy ray curable resin composition A, and the cured resin film 16b. Formed.
The average period between the convex parts of the obtained film 16 was 100 nm, and the height of the convex parts was 200 nm. When the visibility reflectance and the total light transmittance of the film 16 were measured, the visibility reflectance was 0.09% and the total light transmittance was 95.5%.

<Preparation of adhesive>
Acrylate ester obtained by copolymerizing butyl acrylate (BA), methyl acrylate (MA) and 2-hydroxyethyl acrylate (2HEA) at BA / MA / 2HEA = 79/20/1 (mass ratio) 100 parts by mass of a copolymer (mass average molecular weight: 700,000, solid content: 30% by mass), 0.5 parts by mass of an isocyanate compound (“TD-75” manufactured by Soken Chemical Co., Ltd.) as a crosslinking agent, As an additive, 0.01 part by mass of a silane coupling agent (“KBM403” manufactured by Shin-Etsu Chemical Co., Ltd.) was mixed to obtain an adhesive. The obtained adhesive was diluted with methyl ethyl ketone to prepare an adhesive coating solution having a nonvolatile content concentration of 25% by mass.

<Manufacture of laminates>
Using a knife coater, apply the obtained adhesive coating solution to the release agent-treated surface of a release film (“SP-PET 381031C”, manufactured by Lintec Corporation, thickness: 38 μm) so that the thickness after drying is 25 μm. And dried at 90 ° C. for 60 seconds to form an adhesive layer on the release film.
About the obtained adhesive layer, the water absorption and the gel fraction were measured. The results are shown in Table 2.
Next, a pressure-sensitive adhesive layer was bonded to the side where the fine uneven structure of the obtained film was not formed, and a laminate in which a release film, a pressure-sensitive adhesive layer, and a film were laminated in this order was obtained.

<Preparation of test piece (iii)>
The obtained laminate was cut into a size of 70 mm × 50 mm, the release film was peeled to expose the pressure-sensitive adhesive layer, and the exposed surface was immersed in water.
Separately, the surface of a glass plate (manufactured by Matsunami Glass Industrial Co., Ltd., “Large slide glass, product number: S9112”, 76 mm × 52 mm size) was soaked with detergent water (0.003 mass% aqueous solution of “Cucut” manufactured by Kao Corporation). .
Next, the laminate was stuck on the surface of the glass plate soaked with detergent water through an adhesive layer to prepare a test piece (iii).
About the obtained test piece (iii), peeling / whitening after endurance, peelability after endurance, and whitening / swelling after sticking the laminate to a glass plate were confirmed. The results are shown in Table 2.

[Example 2]
A test piece (iii) was prepared in the same manner as in Example 1 except that the surface of the glass plate was immersed in water instead of the washing water, peeling and whitening after durability, peelability after durability, and glass plate Whitening / swelling after the laminate was adhered to was confirmed. The results are shown in Table 2.

[Example 3]
Butyl acrylate (BA), methyl acrylate (MA), 2-hydroxyethyl acrylate (2HEA) and methacrylamide (MAAm) are BA / MA / 2HEA / MAAm = 69.5 / 20/10 / 0.5 ( Example 1 except that an adhesive coating solution was prepared using an acrylic ester copolymer (mass average molecular weight: 650,000, solid content: 30% by mass) obtained by copolymerization at a mass ratio). A laminate and a test piece (iii) were prepared in the same manner as above, and peeling / whitening after durability, releasability after durability, and whitening / swelling after sticking the laminate to a glass plate were confirmed. The results are shown in Table 2.

[Example 4]
A laminate and a test piece (iii) were prepared in the same manner as in Example 1 except that the pressure-sensitive adhesive coating solution was prepared by changing the amount of the crosslinking agent to 0.05 parts by mass. Whitening, releasability after endurance, and whitening / swelling after sticking the laminate to a glass plate were confirmed. The results are shown in Table 2.

[Example 5]
A laminate and a test piece (iii) were prepared in the same manner as in Example 1 except that the adhesive coating solution was prepared by changing the blending amount of the crosslinking agent to 0.4 parts by mass. Whitening, releasability after endurance, and whitening / swelling after sticking the laminate to a glass plate were confirmed. The results are shown in Table 2.

[Example 6]
A laminate and a test piece (iii) were prepared in the same manner as in Example 1 except that the adhesive coating solution was prepared by changing the blending amount of the cross-linking agent to 0.3 parts by mass. Whitening, releasability after endurance, and whitening / swelling after sticking the laminate to a glass plate were confirmed. The results are shown in Table 2.

[Example 7]
A laminate and a test piece (iii) were prepared in the same manner as in Example 1 except that the adhesive coating solution was prepared by changing the blending amount of the crosslinking agent to 0.9 parts by mass. Whitening, releasability after endurance, and whitening / swelling after sticking the laminate to a glass plate were confirmed. The results are shown in Table 2.

[Example 8]
Acrylic acid ester system obtained by copolymerizing butyl acrylate (BA), 2-hydroxyethyl acrylate (2HEA), and diethylacrylamide (DEAA) at BA / 2HEA / DEAA = 70/10/20 (mass ratio). A laminate and a test piece (iii) were prepared in the same manner as in Example 1 except that an adhesive coating solution was prepared using a copolymer (mass average molecular weight: 550,000, solid content: 30% by mass). Then, peeling / whitening after endurance, releasability after endurance, and whitening / swelling after sticking the laminate to a glass plate were confirmed. The results are shown in Table 2.

[Comparative Example 1]
Acrylate ester copolymer obtained by copolymerizing butyl acrylate (BA) and acrylic acid (AA) at BA / AA = 90/10 (mass ratio) (mass average molecular weight: 600,000, solid content: 30 mass%) except that the pressure sensitive adhesive coating solution was prepared, and a laminate and a test piece (iii) were prepared in the same manner as in Example 1, peeling / whitening after endurance, peelability after endurance, And the whitening and swelling after sticking of the laminated body to a glass plate were confirmed. The results are shown in Table 2.

[Comparative Example 2]
A laminate and a test piece (iii) were prepared in the same manner as in Example 1 except that the pressure-sensitive adhesive coating solution was prepared by changing the blending amount of the crosslinking agent to 0.01 parts by mass. Whitening, releasability after endurance, and whitening / swelling after sticking the laminate to a glass plate were confirmed. The results are shown in Table 2.

In addition, the symbol in Table 2 is as follows.
BA: butyl acrylate.
MA: methyl acrylate.
-2HEA: 2-hydroxyethyl acrylate.
MAAm: methacrylamide.
DEAA: diethyl acrylamide.
AA: acrylic acid.
TD-75: Isocyanate compound (“TD-75” manufactured by Soken Chemical Co., Ltd.).
KBM403: Silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., “KBM403”).

As is clear from Table 2, the laminates obtained in Examples 1 to 8 having the pressure-sensitive adhesive layer made of the pressure-sensitive adhesive that can be peeled off from the base material while maintaining the sticking to the base material after the endurance were obtained. In addition to having good adhesiveness to the base material, it could be easily peeled off if it was intentionally peeled off even if it was attached to the base material for a long time. Moreover, the laminated body of each Example was equipped with the film which is the visibility reflectance 0.09% and the total light transmittance 95.5%, and had the outstanding antireflection function.
In particular, in the case of Examples 1 to 7 using a pressure-sensitive adhesive that does not contain a carboxyl group, has a water absorption of 0.01 to 3%, and a gel fraction of 10 to 100%, use water or an aqueous solution. Even when the laminate was stuck on the base material, the pressure-sensitive adhesive layer did not whiten or swell. Moreover, it was difficult for the pressure-sensitive adhesive layer to be whitened even after durability.
In the case of Example 8 using an adhesive having a water absorption rate of 8%, the adhesive layer is likely to whiten or swell when the laminate is stuck on the substrate using water or an aqueous solution. It was. Moreover, the pressure-sensitive adhesive layer was easily whitened after durability.

On the other hand, the laminate obtained in Comparative Example 1 provided with an adhesive layer made of an adhesive that cannot be peeled off from the substrate after the endurance has the same antireflection function and adhesion as the laminate obtained in each Example. However, when it was stuck to the base material for a long time, it was difficult to peel off from the base material even if it was intentionally peeled off.
The laminate obtained in Comparative Example 2 provided with an adhesive layer composed of an adhesive that cannot maintain adhesion to the substrate after durability has the same antireflection function as the laminate obtained in each Example. However, the adhesive layer was easily peeled off from the substrate when it was stuck to the substrate for a long time.

  10: article, 12: substrate, 14: laminate, 16: film, 18: pressure-sensitive adhesive layer.

Claims (4)

A laminate comprising a film having a fine concavo-convex structure formed on one surface and a pressure-sensitive adhesive layer laminated on the other surface of the film, and is attached to a substrate via the pressure-sensitive adhesive layer. ,
The said adhesive layer is a laminated body which consists of an adhesive which can peel from a base material, maintaining adhesion to the said base material, after 500 hours pass in the atmosphere of temperature 60 degreeC, and humidity 90% RH.   The said adhesive layer is a laminated body of Claim 1 which consists of an adhesive which does not whiten even if it sticks on a base material using water or aqueous solution.   The laminate according to claim 1 or 2, wherein the pressure-sensitive adhesive layer comprises a pressure-sensitive adhesive that does not contain a carboxyl group, has a water absorption of 0.01 to 3%, and has a gel fraction of 10 to 100%. . The article | item which has a base material and the laminated body as described in any one of Claims 1-3 stuck on this base material through the adhesive layer.

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