JP5940662B2 - Method for producing antireflection film - Google Patents

Description

The present invention relates to a method for producing an antireflection film. More specifically, the present invention relates to a method for producing a moth-eye film that can reduce surface reflection by sticking on an article.

In recent years, as a technique for reducing the surface reflection of a display device, a moth-eye structure that can obtain an antireflection effect without using a conventional optical interference film has been attracting attention. The moth-eye structure is arranged with a fine pattern of concave and convex patterns that are smaller than the visible light wavelength on the surface of the article to be anti-reflective treated, which is smaller than that of the antiglare (AG) film. Thus, the change in refractive index at the boundary between the outside world (air) and the surface of the article is made pseudo-continuous, and almost all of the light is transmitted regardless of the refractive index interface. Light reflection can be almost eliminated (see, for example, Patent Documents 1 and 2).

Such a moth-eye structure is generally used by being attached to the outermost surface of an article in order to transmit light by eliminating a change in the refractive index of the air interface in a pseudo manner.

The moth-eye film is produced using nanoimprint lithography. In nanoimprint lithography, a mold on which a nanostructure pattern is formed is directly pressed against a transfer resin, and thus the mold is subjected to a mold release process so that the transfer resin does not adhere. As a mold release treatment method, a method of covering the mold with a fluorine-containing monomolecular self-assembled monolayer (SAM) is the mainstream. In addition, by applying a release agent on the transfer resin before the mold is pressed, a release process that prevents a part of the transfer resin from adhering to the mold side without performing a release process on the mold surface. A method has also been proposed (see, for example, Patent Document 3).

Japanese Patent No. 4368384 Japanese Patent No. 4368415 JP 2010-45092 A

Since the moth-eye structure has a plurality of protrusions formed on the surface at intervals or pitch sizes in the order of nanometers, if dirt adheres to the surface, the protrusions become relatively low, and the refractive index at the boundary between the outside world and the article surface It becomes impossible to make the change of the pseudo-continuous. In view of this, a method of coating the surface of the moth-eye film with an antifouling agent such as a water repellent material to prevent dirt from adhering can be considered.

However, if an antifouling agent is applied after the moth-eye structure is formed, a liquid pool is formed in the recess, and the reflectance of the moth-eye film increases. Also in the manufacturing process, if an antifouling agent is applied after forming the moth-eye structure, the number of processes increases and the manufacturing time becomes longer.

Further, in the mold release processing method for covering the mold with SAM or the like as described above, when nanoimprint lithography is repeated, the effect of the mold release agent is gradually lost, and the moth-eye structure cannot be accurately transferred.

The present invention has been made in view of the above situation, and can form a moth-eye structure, an antifouling treatment on the surface of an antireflection film, and a mold release treatment in a series of manufacturing steps. And it aims at providing the manufacturing method of the anti-reflective film which can prolong the lifetime of a mold.

The inventors of the present invention have made various studies on a method for coating a moth-eye film with an antifouling agent, and focused on a method for applying an antifouling agent on a transfer resin before forming a moth-eye structure. Then, after applying the antifouling agent to the surface of the transfer resin, the mold is pressed against the transfer resin, whereby the nanostructure pattern of the mold is transferred to the transfer resin. Was applied to the surface of the transfer resin, so that no liquid pool was generated in the recesses of the transfer resin, and an antifouling effect could be imparted while maintaining the moth-eye structure.

In addition, after applying a mold release agent to the mold surface, the mold was pressed against the transfer resin to pay attention to the method of transferring the nanostructure pattern of the mold to the transfer resin, and also served as a mold release action and an antifouling action. By applying the compound to the surface of the transfer resin, the mold can be released from the mold every time it is transferred, and the life of the mold can be extended. It has been found that it can be sufficiently retained to provide an antifouling effect. In addition, in the conventional method of applying the release agent only to the mold surface or the conventional method of applying the release agent only to the transfer resin surface, the release agent (antifouling agent) remains sufficiently on the transfer resin. I can't let you.

And furthermore, according to the said method, it discovered that the antifouling process to the surface of a moth-eye film and the mold release process to a mold could be performed in a series of manufacturing processes.

Thus, the present inventors have conceived that the above problems can be solved brilliantly, and have reached the present invention.

That is, one aspect of the present invention is a step of laminating a transfer resin on a substrate, a step of applying a release / antifouling material to the transfer resin surface, and a step of applying a release / antifouling material to the mold surface. And applying a mold release / antifouling material to the transfer resin surface and the mold surface, respectively, and then pressing the mold against the transfer resin to transfer the nanostructure pattern of the mold to the transfer resin. The structure pattern is a method for producing an antireflection film having a plurality of recesses in which the width between the bottom points of adjacent recesses is not more than the visible light wavelength.

The steps included in the method for producing an antireflection film are not particularly limited by other steps as long as such steps are included as essential. Hereafter, each process included in the manufacturing method of the said antireflection film and its preferable process are explained in full detail. In addition, the process which combined two or more each preferable process of the manufacturing method of the following antireflection film is also a preferable process of the manufacturing method of the said antireflection film.

The base material is not particularly limited as long as an antireflection film can be placed thereon.

The transfer resin is a resin to which the nanostructure pattern is transferred by pressing a mold, and a thermosetting resin or a photocurable resin that is cured under predetermined conditions is preferably used. Furthermore, it is preferable to use an ultraviolet curable resin from the viewpoint of improving productivity.

The mold release / antifouling material is a material that functions as both a mold release agent for the mold and an antifouling agent for the antireflection film, and examples thereof include a material containing a fluorine compound, a silicon compound, and the like.

The manufacturing method includes a step of applying a mold release / antifouling material to the mold surface. By applying a mold release / antifouling material to the mold surface, the mold release / antifouling material applied to the transfer resin side moves to the mold side when the mold is pressed against the transfer resin in the subsequent process. Can be prevented. Further, it is possible to prevent the transfer resin from being caught in the mold in the in-line manufacturing process.

The manufacturing method includes a step of applying a mold release / antifouling material to the transfer resin surface and then pressing the mold against the transfer resin to transfer the nanostructure pattern of the mold to the transfer resin. By performing transfer after applying the mold release / antifouling material to the surface of the transfer resin, it is possible to prevent the mold release / antifouling material from accumulating in the recesses of the transfer resin to which the moth-eye structure has been transferred.

According to the manufacturing method described above, the antifouling treatment on the surface of the transfer prevention film and the mold release treatment on the mold can be performed in a series of production steps, and the mold release / antireflection applied to the transfer resin side. It is possible to prevent the soiling material from moving to the mold side and continuously supply the mold release / antifouling material to the mold side.

The nanostructure pattern of the mold has a plurality of recesses in which the width between the bottom points of adjacent recesses is equal to or less than the visible light wavelength. In the present specification, the “visible wavelength or shorter” means 380 nm or lower, which is the lower limit of a general visible light wavelength range, more preferably 300 nm or shorter, and still more preferably about ½ of the visible light wavelength. 200 nm or less. By transferring a nanostructure pattern having a plurality of recesses in which the width between the bottom points of the adjacent recesses is less than or equal to the visible light wavelength to the transfer resin, the width between the apexes of the adjacent protrusions is less than or equal to the visible light wavelength. A nanostructure pattern (moth eye structure) having a plurality of convex portions can be produced. If the width between the bottoms of the recesses exceeds 400 nm, the surface of the produced antireflection film may be colored with a blue wavelength component, but the influence is sufficiently suppressed by setting the width to 300 nm or less. When the thickness is 200 nm or less, there is almost no influence.

The antireflection film has a plurality of convex portions in which the width between vertices of adjacent convex portions is equal to or less than the visible light wavelength. By having such a nanostructure pattern (moth eye structure), reflection that occurs on the surface on which the antireflection film is attached can be reduced. For example, by sticking the antireflection film of the present invention on the front plate of the display device, a display device that performs good display with less reflection of surroundings (for example, a fluorescent lamp in a room) due to external light reflection is obtained. Can do.

The release / antifouling material preferably contains a fluorine compound. Since the fluorine compound has an effect of lowering the surface energy, the transfer resin can be prevented from adhering to the mold by applying the release / antifouling material to the mold. Moreover, the antifouling effect can be given to the transfer resin by applying the release / antifouling material to the transfer resin. As a fluorine compound, the compound which has a fluoroalkyl group is mentioned, for example.

It is preferable to include a step of modifying the surface of the transfer resin before the step of applying the release / antifouling material to the surface of the transfer resin. The above-mentioned “surface modification” means that the surface properties are changed by introducing a functional group into the chemical structure constituting the transfer resin surface, and the purpose is to increase the reactivity of the transfer resin surface. . Specifically, a method of irradiating a corona discharge excited by a high-frequency power source, a method of performing ozone treatment, a method of irradiating an excimer laser with a short wavelength and low permeability, a method of performing plasma treatment, and the like can be given. Examples of the functional group to be introduced include —OH group, —COOH group, —NH ₂ group and the like, and —OH group is preferable. Examples of the release / antifouling material applied to the transfer resin surface when -OH groups are introduced by surface modification include siloxane compounds and isocyanate compounds, and siloxane compounds are preferred.

The fluorine compound is preferably a siloxane compound having a fluoroalkyl group. When the surface of the transfer resin is surface-modified by applying a material containing a siloxane compound, the silicon atom (Si) of the siloxane compound and the functional group introduced on the surface of the transfer resin by the surface modification React to chemically bond the component contained in the transfer resin and the component contained in the mold release / antifouling material, and firmly bond them. By introducing such a chemical bond, the release / antifouling material can be made difficult to peel off from the transfer resin surface even when the antireflection film surface is wiped off.

The fluorine compound is preferably a compound having a fluoroalkyl group and a polymerizable group. By applying a material containing the compound, the polymerizable group can be polymerized, and the transfer resin and the release / antifouling material can be chemically bonded. By introducing such a chemical bond, the release / antifouling material can be made difficult to peel off from the transfer resin surface even when the antireflection film surface is wiped off.

The polymerizable group is preferably an acrylate group and / or a methacrylate group. The transfer resin and the mold release / antifouling material can be firmly bonded by an easy process such as heating and light (for example, ultraviolet ray) irradiation.

The step of transferring the nanostructure pattern to the transfer resin preferably includes a step of irradiating the transfer resin with ultraviolet rays at the same time as pressing the mold against the transfer resin. Curing of the transfer resin during transfer of the nanostructure pattern and chemical bonding between the component contained in the transfer resin and the component contained in the mold release / antifouling material can be performed simultaneously.

According to the present invention, the formation of a moth-eye structure, the antifouling treatment on the surface of the antireflection film, and the mold release treatment on the mold can be carried out in a series of manufacturing steps, and the lifetime of the mold is extended. Can be

1 is a schematic cross-sectional view of an antireflection film of Embodiment 1. FIG. The schematic diagram showing the manufacturing process of the mold of Embodiment 1. FIG. The schematic diagram showing the manufacturing process of the antireflection film of Embodiment 1. FIG. The schematic diagram showing the manufacturing process in-line of the antireflection film of Embodiment 1. FIG. FIG. 3 is a schematic cross-sectional view of an antireflection film of Embodiment 2. The schematic diagram showing the manufacturing process of the antireflection film of Embodiment 2. FIG. The schematic diagram showing the manufacturing process in the in-line of the antireflection film of Embodiment 2. FIG. The cross-sectional schematic diagram of the antireflection film of the comparative example 1. FIG. The cross-sectional schematic diagram of the antireflection film of the comparative example 2. FIG.

Embodiments will be described below, and the present invention will be described in more detail with reference to the drawings. However, the present invention is not limited only to these embodiments.

(Embodiment 1)
FIG. 1 is a schematic cross-sectional view of the antireflection film of Embodiment 1. As shown in FIG. 1, the antireflection film of Embodiment 1 has a transfer resin 11 and a film (release / antifouling material) 13 formed on the transfer resin 11 via a chemical bonding layer 12. , Pasted on the substrate 10.

In the first embodiment, the transfer resin 11 has a moth-eye structure, and most of the light incident on the surface of the antireflection film is the interface between the air and the transfer resin 11 and the transfer resin 11 and the substrate. Therefore, it is possible to obtain a far superior antireflection effect as compared with the conventional light interference type antireflection film. The antireflection film according to Embodiment 1 includes, for example, constituent members of a display device (self-luminous display element, non-self-luminous display element, light source, light diffusion sheet, prism sheet, polarizing reflection sheet, retardation plate, polarizing plate, (Front plate, housing, etc.), lens, window glass, frame glass, show window, water tank, printed matter, photograph, painted article, lighting equipment, and the like.

Below, the manufacturing method of the anti-reflective film which concerns on specific Embodiment 1 is demonstrated.

<Mold production>
Below, the example which produced the metal mold | die (mold) for actually forming an antireflection film is demonstrated using FIG. FIG. 2 is a schematic diagram illustrating a manufacturing process of the mold according to the first embodiment.

First, an Al base material 21 is prepared (FIG. 2 (a)). Next, as shown in FIG. 2 (b), the Al base material 21 is partially (surface part) anodized to obtain porous alumina. The layer 20 was formed and etched to form the recess 22a. The size of the recess 22a, the generation density, the depth of the recess 22a, and the like can be controlled according to the conditions of anodization (for example, the formation voltage, the type and concentration of the electrolytic solution, and the anodization time). By controlling the size, the regularity of the arrangement of the recesses 22a can be controlled.

In the porous alumina layer 20 produced in the initial stage, the arrangement of the recesses 22a tends to be disturbed. Therefore, in consideration of reproducibility, the first embodiment was formed first as shown in FIG. The porous alumina layer 20 was removed. By removing the bottom portion so as to leave only a portion having a substantially equal distance, the position where the hole is opened can be determined in the next anodizing step (FIG. 2D).

Thereafter, as shown in FIG. 2D, anodic oxidation was performed again to form a porous alumina layer 20 having a recess 22a. Next, as shown in FIG. 2 (e), the porous alumina layer 20 having the recesses 22a was brought into contact with an alumina etchant and etched by a predetermined amount to enlarge the hole diameter of the recesses 22a. Here, anodization is performed by applying a voltage of 80 V to an electrolyte solution of oxalic acid 0.6% and a liquid temperature of 5 ° C. for 24 seconds, and a solution of phosphoric acid 1 mol / L and a liquid temperature of 30 ° C. for 25 minutes. Etching was performed by dipping.

Thereafter, as shown in FIG. 2 (f), the Al base material 21 was partially anodized again to grow the recess 22 a in the depth direction and to thicken the porous alumina layer 20. Here, since the growth of the recess 22a starts from the bottom of the already formed recess 22a, the side surface of the recess 22a is stepped. Thereafter, as shown in FIG. 2 (g), the porous alumina layer 20 was further etched by bringing it into contact with an alumina etchant, thereby further expanding the hole diameter of the recess 22a.

Thus, the porous alumina layer 20 provided with the recessed part 22a which has a desired uneven | corrugated shape is obtained by repeating the anodic oxidation process (FIG.2 (d)) and etching process (FIG.2 (e)) which were mentioned above. Here, the above anodization and etching were alternately performed, and the anodization was performed 5 times and the etching was performed 4 times, and a mold having a conical hole with a pitch of adjacent holes of 200 nm and a height of 400 nm was produced. .

<Preparation of antireflection film>
Below, the manufacturing method of the anti-reflective film which concerns on Embodiment 1 is demonstrated using FIG. FIG. 3 is a schematic diagram illustrating a manufacturing process of the antireflection film of the first embodiment.

First, as shown to Fig.3 (a), the base material 10 is prepared, the transfer resin 11 is apply | coated, and it is made to dry. The kind of base material is not specifically limited, For example, what uses glass, a plastics, a metal, etc. as a constituent material is mentioned. The transfer resin 11 is not particularly limited, but in the case of optical nanoimprint, an ultraviolet curable resin is preferably used, and examples thereof include PAK01 (manufactured by Toyo Gosei Co., Ltd.) and SU-8 (manufactured by Nippon Kayaku Co., Ltd.). It is done.

Next, as shown in FIG. 3B, the surface modification of the transfer resin 11 is performed. By surface modification, the functional group 14 can be introduced into the chemical structure constituting the surface of the transfer resin 11 to increase the reactivity of the transfer resin surface. Examples of the functional group to be introduced include —OH group, —COOH group, —NH ₂ group and the like, and —OH group is preferable. As the surface modification method, a method in which the transfer resin is exposed to ultraviolet rays or the like and the transfer resin does not deteriorate is preferably used. Specifically, a corona discharge excited by a high-frequency power source is applied to the surface of the transfer resin, ozone Examples of the method include a method of performing treatment, a method of irradiating an excimer laser with a short wavelength and low permeability, and a method of performing plasma treatment.

Next, as shown in FIG. 3C, a mold release / antifouling material 13 is applied to the surface of the transfer resin 11 subjected to the surface modification and dried. The mold release / antifouling material 13 is not particularly limited as long as it functions as both a mold release agent for the mold and an antifouling agent for the antireflection film. For example, a material containing a siloxane compound having a fluoroalkyl group Are preferably used, and specific examples include Die Free (registered trademark, manufactured by Daikin). By including the siloxane compound, the releasing action works, and by including the fluoroalkyl group, the antifouling function is exhibited. The silicon atom (Si) contained in the siloxane compound and the —OH group introduced on the surface of the transfer resin 11 by the surface modification react to form a chemical bond layer 12 composed of —O—Si—O— bonds. The That is, the mold release / antifouling material 13 has an effect as a mold release agent when the mold is pressed, and has an effect as an antifouling agent after the moth-eye structure is formed.

Next, as shown in FIG. 3D, a mold release / antifouling material 13 is applied to the surface of the mold 31 produced by the method described above. By applying the mold release / antifouling material 13 to the mold 31, the mold release / antifouling material 13 that functions as an antifouling agent can be easily left on the transfer resin 11 even after transfer. Further, by applying the mold release / antifouling material 13 on the transfer resin 11, the mold 31 can be transferred while supplying the mold release agent. Can be

Next, as shown in FIG. 3E, the mold 31 is pressed against the transfer resin 11 on which the chemical bonding layer 12 and the release / antifouling material 13 are laminated, and irradiated with ultraviolet rays to transfer the mold 31. The resin 11 is cured, and the nanostructure pattern formed on the mold 31 is transferred to the transfer resin 11. Through the above steps, the antireflection film of Embodiment 1 is completed (FIG. 3F).

The manufacturing process in the sequential (batch) process has been described above. However, as shown below, the in-line continuous process can be performed. FIG. 4 is a schematic view showing an in-line manufacturing process of the antireflection film of Embodiment 1. Production steps (a) to (f) in FIG. 4 correspond to the production steps (a) to (f) in FIG.

First, the transfer resin 11 is applied to the substrate 10 (FIG. 4A), and the transfer resin 11 is dried in a drying furnace. Next, surface modification is performed, and functional groups 14 are introduced into the chemical structure constituting the surface of the transfer resin 11 (FIG. 4B). Next, the release / antifouling material 13 is applied to the transfer resin 11 and the mold 31 (FIGS. 4C and 4D). In the step of FIG. 4C, the silicon atom (Si) included in the siloxane compound that is a mold release / antifouling material reacts with the functional group 14 to form the chemical bonding layer 12. Further, after drying in a drying furnace, UV irradiation is performed to perform transfer (FIG. 4E). In the in-line manufacturing, the mold 31 uses a roll type mold. Through the above steps, the antireflection film of Embodiment 1 is completed (FIG. 4F).

(Embodiment 2)
The second embodiment is the same as the first embodiment except that a material containing a compound having a fluoroalkyl group and a polymerizable group is used as the mold release / antifouling material, and the surface modification of the transfer resin is not performed. . Embodiment 2 can be suitably used for optical nanoimprint.

FIG. 5 is a schematic cross-sectional view of the antireflection film of Embodiment 2. As shown in FIG. 5, the antireflection film of Embodiment 2 has a transfer resin 101 and a film (release / antifouling material) 103 formed on the transfer resin 101 via a chemical bonding layer 102. , Pasted on the substrate 100.

Below, the manufacturing method of the anti-reflective film which concerns on Embodiment 2 is demonstrated using FIG. FIG. 6 is a schematic diagram illustrating a manufacturing process of the antireflection film of the second embodiment. First, as shown to Fig.6 (a), the base material 100 is prepared, the transfer resin 101 is apply | coated, and it is made to dry. As the base material 100 and the transfer resin 101, the same materials as in the first embodiment can be used.

Next, as shown in FIG. 6B, a release / antifouling material 103 is applied to the surface of the transfer resin 101 and dried. The mold release / antifouling material 103 is a material containing a compound having a fluoroalkyl group and a polymerizable group, and the polymerizable group is preferably an acrylate group and / or a methacrylate group. Specific examples include Fluoro Surf (registered trademark, manufactured by Fluoro Technology). Since the release / antifouling material 103 contains a compound having a polymerizable group, when the transfer resin is cured by ultraviolet irradiation, the polymerizable group also reacts simultaneously with the transfer resin 101 and the release / antifouling material 103. Can be chemically combined. Moreover, antifouling property can be provided to an antireflection film by having a fluoroalkyl group. That is, the mold release / antifouling material 103 has an effect as a mold release agent when pressing the mold, and has an effect as an antifouling agent after the moth-eye structure is formed.

Next, as shown in FIG. 6C, a mold release / antifouling material 103 is applied to the surface of the mold 31 produced by the method described above. By applying the mold release / antifouling material 103 to the mold 31, the mold release / antifouling material 103 that functions as an antifouling agent can be easily left on the transfer resin 101 even after transfer. In addition, by applying the mold release / antifouling material 103 on the transfer resin 101, the mold 31 can be transferred while supplying a mold release agent, so that the service life of the mold 31 is prolonged. be able to.

Next, as shown in FIG. 6 (d), the mold 31 is pressed against the transfer resin 101 having the release / antifouling material 103 laminated on the surface, irradiated with ultraviolet rays to cure the transfer resin 101, and the mold. The nanostructure pattern formed on 31 is transferred to the transfer resin 101. Moreover, the polymerizable group contained in the mold release / antifouling material 103 reacts by the ultraviolet irradiation, and a chemical bonding layer 102 is formed between the mold release / antifouling material 103 and the transfer resin 101. The antireflection film is completed through the above steps (FIG. 6E).

The manufacturing process in the sequential (batch) process has been described above. However, as shown below, the in-line continuous process can be performed. FIG. 7 is a schematic view showing an in-line manufacturing process of the antireflection film of Embodiment 2. Manufacturing steps (a) to (e) in FIG. 7 correspond to the manufacturing steps (a) to (e) in FIG.

First, the transfer resin 101 is applied to the substrate 100 (FIG. 7A), and the transfer resin 101 is dried in a drying furnace. Next, a release / antifouling material 103 is applied to the transfer resin 101 and the mold 31 (FIGS. 7B and 7C). Further, after drying in a drying furnace, UV irradiation is performed to perform transfer (FIG. 7D). By the ultraviolet irradiation, the polymerizable group contained in the mold release / antifouling material 103 reacts to form the chemical bonding layer 102. In the in-line manufacturing, the mold 31 uses a roll type mold. Through the above steps, the antireflection film of Embodiment 2 is completed (FIG. 7E).

Example 1
In Example 1, an antireflection film was actually produced by the manufacturing method according to Embodiment 1. First, a base material was prepared, a transfer resin was applied on the base material, and dried for 1 minute on an 80 ° C. hot plate. PAK01 (manufactured by Toyo Gosei Co., Ltd.) was used as the transfer resin. Next, surface modification was performed on the transfer resin. The surface modification was performed by irradiating the resin surface with corona discharge excited by a high frequency power source with a discharge amount of 40 W · min / m ² using a corona discharge treatment apparatus. Next, a release / antifouling material was applied to the surface of the transfer resin that had undergone surface modification, and dried on a hot plate at 80 ° C. for 1 minute. Fluorosurf (manufactured by Fluoro Technology Co., Ltd.) was used as the mold release / antifouling material. Next, the same mold release / antifouling material as the mold release / antifouling material applied to the surface of the transfer resin (Fluorosurf (manufactured by Fluoro Technology)) is applied to the surface of the mold produced by the method described in the first embodiment. It was applied, the mold was pressed against the transfer resin, and light with a wavelength of 365 nm was irradiated with an illuminance of 1.5 J / m ² to transfer the nanostructure pattern.

(Example 2)
In Example 2, an antireflection film was actually produced by the manufacturing method according to Embodiment 2. First, a base material was prepared, a transfer resin was applied on the base material, and dried on an 80 ° C. hot plate for 1 minute. PAK01 (manufactured by Toyo Gosei Co., Ltd.) was used as the transfer resin. Next, an isopropyl alcohol (IPA) solution of 2- (perfluorohexylethyl acrylate) as a mold release / antifouling material was applied to the surface of the transfer resin and dried on a hot plate at 70 ° C. for 1 minute. Next, a mold release / antifouling material (Fluorosurf (manufactured by Fluoro Technology)) different from the mold release / antifouling material applied to the surface of the transfer resin is applied to the surface of the mold produced by the same method as in Example 1. Then, the mold was pressed against the transfer resin, and light with a wavelength of 365 nm was irradiated at an illuminance of 1.5 J / m ² to transfer the nanostructure pattern.

(Evaluation test)
In addition to the antireflection films of Example 1 and Example 2, the antireflection films of Comparative Example 1 and Comparative Example 2 were also produced, and the antireflection films of Example 1, Example 2, Comparative Example 1, and Comparative Example 2 were prepared. The reflectivity and wiping property were examined. Moreover, the contact angle of water with respect to the mold surface of the mold used for manufacture of Example 1, Example 2, Comparative Example 1, and Comparative Example 2 was examined. In Comparative Example 1, the moth-eye structure was transferred to a transfer resin using a mold whose surface was subjected to release treatment with SAM, and then a release / antifouling material (die-free (Daikin)) was applied. And dried. In Comparative Example 2, a release / antifouling material (Fluorosurf (manufactured by Fluoro Technology)) is applied to the surface of the transfer resin and dried, and then a moth-eye structure is used for the transfer resin using a mold that has not been subjected to a release treatment. Was transcribed. In Comparative Examples 1 and 2, a mold produced by the method described in Embodiment 1 was used. 8 and 9 are schematic cross-sectional views of the antireflection films of Comparative Examples 1 and 2, respectively.

Table 1 is a table showing the reflectivities of Example 1, Example 2, Comparative Example 1, and Comparative Example 2. The reflectance was measured in SCE mode using CM2600d (manufactured by Konica Minolta).

In Example 1, Example 2, and Comparative Example 2, the reflectance was about 0.3%, and good results were obtained. Comparative Example 1 had a reflectance of 0.53, which was higher than that of other Examples and Comparative Examples.

In Comparative Example 1, since the antifouling agent is applied after the moth-eye structure is transferred to the transfer resin, the release / antifouling material 43 accumulates in the recesses as shown in FIG. It is considered that the height of the convex portion of the structure is lower than the case where the release / antifouling material 43 is not applied. As a result, it is considered that the characteristics of the moth-eye structure are impaired and the reflectance is increased.

In Example 1, Example 2, and Comparative Example 2, since the mold release / antifouling material was applied to the transfer resin before forming the moth-eye structure, the liquid could not be accumulated and the reflectance increased as in Comparative Example 1. It is thought that was not observed.

Table 2 is a table showing the repeated wiping properties of Example 1, Example 2, Comparative Example 1, and Comparative Example 2. The wiping property of the transfer resin surface is wiped 10 times with a neutral detergent, and then the surface of the transfer resin is visually checked to see if there is any peeling of the release / antifouling material that causes uneven reflection. Observed. After wiping off the surface of the transfer resin, it was rated as ○ when no wiping unevenness occurred, and x when wiping unevenness occurred.

Even after Example 10 and Example 2 were wiped 10 times repeatedly, no wiping unevenness was observed, and good results were obtained. On the other hand, in Comparative Example 1 and Comparative Example 2, wiping unevenness was observed.

In Comparative Example 1, the mold release / antifouling material 43 was applied on the transfer resin, but no chemical bond was introduced between the transfer resin and the mold release / antifouling material 43. It is considered that the mold release / antifouling material 43 was removed and wiping unevenness was observed. In Comparative Example 2, as shown in FIG. 9, it is considered that the release / antifouling material 43 applied on the transfer resin 41 on the substrate 40 remains slightly on the resin even after transfer. However, since no chemical bond is introduced between the transfer resin 41, it is considered that when repeated wiping was performed, the remaining mold release / antifouling material 43 was removed and reflection unevenness was observed.

On the other hand, in Example 1, the resin surface was surface-modified to improve the reactivity to the mold release / antifouling material, and then a transfer resin was applied by applying a material containing a siloxane compound having a fluoroalkyl group. -O-Si-O- bonds are formed between the mold and the mold release / antifouling material. In Example 2, a material containing a compound having a polymer group is used as the mold release / antifouling material, and the transfer resin and the mold release / antifouling material are chemically bonded by ultraviolet irradiation. In both Examples 1 and 2, since a chemical bond is introduced between the transfer resin and the release / antifouling material, it is considered that no reflection unevenness was observed even after repeated wiping.

Table 3 is a table in which the contact angles of water with respect to the mold surface of the molds used in the manufacture of Example 1, Example 2, Comparative Example 1, and Comparative Example 2 are described. The contact angle of water with each mold surface was compared before transferring to the transfer resin and after transferring 100 times to the transfer resin.

In the molds used in the manufacture of Example 1 and Example 2, even after 100 times of transfer, the contact angle of water with the mold surface does not change much compared to before transfer, and 100 times before transfer. Later, good results were obtained. On the other hand, in the mold used for the manufacture of Comparative Example 1, the contact angle of water with the mold surface after 100 times of transfer was greatly reduced as compared with that before transfer. In the mold used for the manufacture of Comparative Example 2, the contact angle of water with the mold surface in the initial state is significantly lower than in Example 1, Example 2, and Comparative Example 1, and the water with respect to the mold surface after 100 times of transfer The contact angle of was higher than before the transfer.

In the manufacture of Comparative Example 1, only the mold release process is performed before the transfer, and the mold release / antifouling material is not supplied during the manufacturing process. For this reason, it is considered that when the transfer is repeated, the mold release / antifouling material is lost from the mold and the contact angle with water is lowered. In the manufacture of Comparative Example 2, since the mold release process is not performed before the transfer, the contact angle of water with the mold surface before the transfer is low, and the mold release / antifouling applied on the transfer resin by repeating the transfer. It is thought that the material moved to the mold and the contact angle of water with the mold surface was increased.

On the other hand, in the manufacture of Examples 1 and 2, a release / antifouling material is applied to the transfer resin side. Since the mold release / antifouling material also has a function as a mold release agent, it is considered that the same effect as when the mold release agent is continuously supplied to the mold at the time of transfer is obtained. Therefore, even if the transfer is repeated, the mold releasability is not impaired. Therefore, it is considered that the resin is not easily clogged in the concave portion of the mold, and the service life of the mold can be extended.

10, 40, 100: base material 11, 41, 101: transfer resin 12, 102: chemical bonding layer 13, 43, 103: mold release / antifouling material 14: functional group 20: porous alumina layer 21: Al base material 22a : Fine concave portion 31 having stepped side surfaces: Mold (mold)

Claims (10)

Laminating a transfer resin on a substrate;
Applying a release / antifouling material to the surface of the transfer resin;
Applying a mold release / antifouling material to the mold surface;
After applying a release / antifouling material to the transfer resin surface and the mold surface, respectively, the mold is pressed against the transfer resin to transfer the nanostructure pattern of the mold to the transfer resin,
Furthermore, before the step of applying a mold release / antifouling material to the transfer resin surface, it has a step of modifying the surface of the transfer resin surface,
The method for producing an antireflection film, wherein the nanostructure pattern has a plurality of recesses in which the width between the bottom points of adjacent recesses is equal to or less than a visible light wavelength. The method for producing an antireflection film according to claim 1, wherein the release / antifouling material contains a fluorine compound. The step of modifying the surface of the transfer resin surface is a step of introducing at least one functional group selected from the group consisting of —OH group, —COOH group, and —NH ₂ group to the transfer resin surface. The manufacturing method of the antireflection film of Claim 1 or 2 . The step of modifying the surface of the transfer resin includes a method of irradiating a corona discharge excited by a high frequency power source, a method of performing an ozone treatment, a method of irradiating an excimer laser with a short wavelength and a low permeability, and a plasma treatment. method for producing an antireflection film according to claim 1 or 2, characterized in that is carried out by at least one method selected from the group consisting of a method of performing. The method for producing an antireflection film according to claim 2, wherein the fluorine compound is a siloxane compound having a fluoroalkyl group. According to claim 5, characterized in that the surface modified transfer resin surface in Table Men'aratame reformed transcription resin surface release / antifouling material after applying includes the step of forming a chemical bond layer A method for producing an antireflection film. The method of manufacturing an antireflection film according to claim 6 , wherein the chemical bonding layer includes —O—Si—O— bonds. The method for producing an antireflection film according to claim 2, wherein the fluorine compound is a compound having a fluoroalkyl group and a polymerizable group. The method for producing an antireflection film according to claim 8 , wherein the polymerizable group is an acrylate group and / or a methacrylate group. The method for producing an antireflection film according to claim 8 or 9 , wherein the step of transferring the nanostructure pattern to a transfer resin includes a step of pressing a mold against the transfer resin and simultaneously irradiating with ultraviolet rays.

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