JP2014184626A - Production method of roll shape mold, and production method of article having two or more salient on surface - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a roll shape mold for imprint in which variation of a pore depth is suppressed.SOLUTION: A production method of a roll shape mold in which an oxide film having two or more pores is formed on a surface of an aluminum base material, includes: (I) a process in which the aluminum base material is anodized in an electrolyte to form an oxide film having two or more pores; and (II) a process in which the aluminum base material is immersed in a process liquid to dissolve at least one part of the oxide film, and after at least one of these processes (I) and (II), takes out the aluminum base material from a liquid so that at least one of the electrolyte and the process liquid may not reside in a gravity direction lower part of the aluminum base material.

Description

  The present invention relates to a method for producing a roll mold and a method for producing an article having a fine concavo-convex structure on the surface.

  An article such as an optical film having a fine concavo-convex structure with a period of less than or equal to the wavelength of visible light on the surface exhibits an antireflection function and the like, and thus its usefulness is attracting attention. In particular, it is known that a fine concavo-convex structure called a moth-eye structure exhibits an effective antireflection function by continuously increasing from a refractive index of air to a refractive index of a material.

  Examples of the method for producing an optical film having a fine concavo-convex structure on its surface include an imprint method in which the fine concavo-convex structure formed on the mold surface is transferred to the surface of a base film (transfer object). For example, the following method is known as the imprint method.

  The ultraviolet curable resin is irradiated with ultraviolet rays in a state where the ultraviolet curable resin is interposed between the roll-shaped mold in which the anodized alumina having a plurality of pores is formed on the outer peripheral surface and the transparent base film. Light that cures the ultraviolet curable resin to form a cured resin layer having a plurality of convex portions whose pores of the anodized alumina are reversed on the surface, and peels the base film from the roll mold together with the cured resin layer Imprint method.

  Moreover, as a manufacturing method of the roll-shaped mold used by the said imprint method, for example, a roll-shaped aluminum base material is anodized in an electrolytic solution, and an anode having a plurality of pores on the outer peripheral surface of the aluminum base material. There is a method of repeatedly performing a step of forming alumina oxide and a pore size expansion step of expanding the pore size.

  Usually, when the anodization of an aluminum base material and the pore diameter for enlarging the pore diameter are repeated, the aluminum base material is immersed in a treatment tank containing an electrolyte such as oxalic acid or sulfuric acid, and a voltage is applied to the anode. Apply oxidation treatment. Next, after cleaning the aluminum base material as necessary, the anodized aluminum base material is immersed in a processing tank containing an etchant such as phosphoric acid or chromic acid / phosphoric acid mixed solution to form an oxide film. A pore size enlargement process for dissolving at least a part is performed, and then the aluminum base material is further washed as necessary.

  By repeating the anodic oxidation step and the pore diameter expansion process as described above, it is possible to manufacture a roll-shaped mold having a tapered pore diameter in which the pore diameter continuously changes (Patent Documents 1 and 2). .

JP 2009-174007 A International Publication No. 2006/059686 Pamphlet

  By the way, when the roll-shaped mold is surface-treated using the methods described in Patent Documents 1 and 2, the roll-shaped aluminum substrate is removed from the treatment tank after anodization and / or after the pore diameter expansion treatment, and the next step is performed. Until then, the shape of the fine concavo-convex structure on the surface of the roll mold changes due to the influence of the electrolyte and etchant attached to the surface of the aluminum base material, resulting in variations in the height of the fine concavo-convex structure formed on the surface. was there.

  In particular, when the roll-shaped mold is taken out from the processing tank, the treatment liquid is dripped from the lower part of the roll-shaped mold shown in FIG. 9 in the direction of gravity, and there is a variation in the height of the fine concavo-convex structure in the strip-shaped single-line region S. There was a problem that it was likely to occur. In addition, the roll-shaped mold of FIG. 9 is the figure which orient | assigned the gravity direction downward upward for the purpose of illustration.

  As shown in FIG. 9, when a variation in height occurs in the single line-shaped region S on the surface of the roll-shaped mold 50, the unevenness height is transferred to the transfer portion 53 that transfers the fine unevenness structure to the molded body by the imprint method. Since there will be variations, the pattern in this region S is transferred to the molded product, resulting in a product defect. In particular, in the case of a roll mold that transfers a concavo-convex structure on the order of nanometers, the above problem becomes significant. Further, when the anodizing treatment and the pore diameter enlargement treatment are repeated, the problem of variation in height may be particularly noticeable.

  As described above, when such a roll-shaped mold is used and the fine concavo-convex structure formed on the surface of the roll-shaped mold is transferred by the imprint method, the height of the convex portion varies depending on the location. In some cases, the article may vary.

  This invention is made | formed in view of the said situation, The 1st side surface of this invention provides the method of manufacturing the roll-shaped mold for imprint in which the dispersion | variation in the depth of a pore was suppressed.

  The second aspect of the present invention provides a method for producing an article having a plurality of convex portions on the surface, in which variations in the height of the convex portions are suppressed.

  That is, according to the present invention, there is provided a method for producing a roll-shaped mold in which an oxide film having a plurality of pores is formed on the surface of an aluminum substrate, wherein (I) an aluminum substrate is anodized in an electrolytic solution. A step of forming an oxide film having a plurality of pores, and (II) a step of immersing the aluminum substrate in a treatment solution to dissolve at least a part of the oxide film, and the step (I) and After the at least one step of (II), the aluminum base material is taken out from the liquid so that at least one of the electrolytic solution and the treatment liquid does not stay in the lower part of the aluminum base material in the direction of gravity. A method for producing a roll mold is provided.

  According to one aspect of the present invention, after at least one of the steps (I) and (II), the aluminum base material is taken out from the liquid while rotating the aluminum base material around the central axis.

  According to another aspect of the present invention, after at least one of the steps (I) and (II), the aluminum base is tilted with respect to the horizontal direction and the aluminum is out of the liquid. The substrate is removed.

  According to another aspect of the present invention, after at least one of the steps (I) and (II), while spraying at least one of a liquid and a gas on the aluminum substrate, the aluminum substrate is out of the liquid. It is taken out.

  According to another aspect of the present invention, the steps (I) and (II) are performed in a single treatment tank containing a mixed solution of two or more kinds of acids.

According to another aspect of the present invention, the steps (I) and (II) are repeated.
According to the present invention, there is also provided a method for manufacturing an article having a fine concavo-convex structure on the surface, wherein a plurality of pores of anodized alumina formed on the outer peripheral surface of a roll-shaped mold obtained by the above-described manufacturing method are provided. There is provided a method for producing an article, which is transferred to an object to be transferred by an imprint method to obtain an article having a plurality of convex portions having inverted pores on the surface.

  This invention is made | formed in view of the said situation, The 1st side surface of this invention can provide the method of manufacturing the roll-shaped mold for imprint in which the dispersion | variation in the depth of the pore was suppressed. .

  The second aspect of the present invention provides a method for producing an article having a plurality of convex portions on the surface, in which variations in the height of the convex portions are suppressed.

It is sectional drawing which shows the formation process of the pore of an anodized alumina. It is a schematic block diagram which shows an example of the apparatus used for manufacture of the roll mold used for this invention. It is a schematic block diagram which shows an example of the apparatus used for manufacture of the roll mold used for this invention. It is a schematic block diagram which shows an example of the roll-shaped mold manufactured by one Embodiment of this invention. It is a schematic block diagram which shows an example of the manufacturing apparatus of articles | goods. It is a schematic block diagram of the articles | goods manufactured by one Embodiment of this invention. It is the figure which image | photographed the roll-shaped mold outer periphery in the Example with the imaging means. It is the figure which image | photographed the roll-shaped mold outer periphery in the comparative example with the imaging means. It is a perspective view which shows typically an example of the roll-shaped mold obtained by the conventional method.

  The present invention will be described in detail below.

  In the present invention, “(meth) acrylate” means “acrylate and / or methacrylate”, and “(meth) acryloyl group” means “methacryloyl group and / or acryloyl group”.

The “active energy ray” means a heat ray such as an electron beam, ultraviolet rays, visible rays, plasma, infrared rays, or the like.
<Method for manufacturing roll mold>
In the manufacturing method of the roll mold of this invention, it is a method of producing a fine uneven structure on the surface of a roll-shaped mold base material. In the present invention, anodized alumina that has a plurality of pores (concave portions) on the surface of an aluminum base (aluminum porous) is used in that the seamless and roll-shaped mold can be easily manufactured. A method of forming an oxide film (alumite) is used.

  More specifically, the roll-shaped mold having anodized alumina on the surface can be produced, for example, through the following (a) to step (e). Each step will be described with reference to FIG.

    (A) A step of forming an oxide film by anodizing a roll-shaped aluminum substrate in an electrolytic solution.

    (B) A step of removing at least a part of the oxide film.

    (C) The process of anodizing again a roll-shaped aluminum base material in electrolyte solution, and forming the oxide film which has several pores.

    (D) A step of removing a part of the pores to enlarge the pore diameter.

(E) A step of repeatedly performing the step (c) and the step (d).
(Step (a)):
In the step (a), a voltage is applied to the roll-shaped aluminum base material 30 in the electrolytic solution to anodize to form the oxide film 44. When the aluminum substrate 30 is anodized, an oxide film 44 having pores 42 is formed.

  The purity of the aluminum substrate is preferably 97 to 99.99% by mass, and more preferably 99.5 to 99.9% by mass. If the purity of aluminum is less than 97% by mass, an irregular structure having a size that scatters visible light due to segregation of impurities may be formed during anodization, or the regularity of pores obtained by anodization may be reduced. This is not preferable.

  By the way, when high-purity aluminum is used, when processing into a desired shape (for example, cylindrical shape), the aluminum base material may be too soft and difficult to process. Therefore, a material obtained by adding magnesium to aluminum and processing it into a predetermined shape may be used as the aluminum substrate 30. By adding magnesium, the strength of aluminum is increased, which makes it easier to process. The amount of magnesium added to aluminum is preferably about 0.1 to 3% by mass relative to the total mass of the aluminum substrate.

  Examples of the electrolytic solution used in the step (a) include an acidic aqueous solution or an alkaline aqueous solution, and an acidic aqueous solution is preferable. Examples of the acidic aqueous solution include inorganic acids (sulfuric acid, phosphoric acid, etc.), organic acids (oxalic acid, malonic acid, tartaric acid, succinic acid, malic acid, citric acid, etc.), and sulfuric acid, oxalic acid, and phosphoric acid are particularly preferable. . A mixture of these may also be used.

When using oxalic acid as electrolyte:
In the step (a), when oxalic acid is used as the electrolyte, the concentration of oxalic acid is preferably 0.7 mol / l (hereinafter simply referred to as “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.

  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:
In the step (a), when sulfuric acid is used as the electrolytic solution, the concentration of sulfuric acid is preferably 0.7 M or less. If the concentration of sulfuric acid exceeds 0.7M, the current value may become too high to maintain a constant voltage.

  The temperature of the electrolytic solution is preferably 30 ° C. or less, and more preferably 20 ° C. or less. 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.

  Since the thickness of the oxide film 44 formed in the step (a) is proportional to the integrated electric quantity that is the product of the current density and the oxidation time, the voltage, current density, and oxidation are dependent on the thickness of the oxide film 44 to be formed. What is necessary is just to change time suitably. The time for applying the voltage to the aluminum substrate 30 is preferably 0.5 minutes or more and 120 minutes or less from the viewpoint of mold productivity.

As for the thickness of the oxide film 44 formed in a process (a), 0.1-10 micrometers is preferable. If the thickness of the oxide film 44 is within this range, when at least a part of the oxide film 44 is removed in the later-described step (b), the machining marks on the surface of the aluminum substrate 30 are sufficiently removed. In addition, since the step of the crystal grain boundary does not become so large as to be visually recognized, it is possible to avoid transfer of macro unevenness derived from the mold to the surface of the molded body.
(Step (b)):
In the step (b), at least a part of the oxide film 44 formed in the step (a) is removed. When a fine irregular structure with high regularity is required, it is preferable to remove all oxide films 44 and form anodic oxidation pore generation points 46 that are regularly arranged. The regularity of the pores 42 can be improved by forming the anodic oxidation pore generation points 46.

  Examples of the method for removing the oxide film 44 include a method in which aluminum is not dissolved but the oxide film 44 is dissolved and removed in a solution that selectively dissolves. Examples of such a solution include a chromic acid / phosphoric acid mixed solution.

In the step (b), the time for immersing the aluminum substrate in the solution may be appropriately adjusted according to the thickness of the oxide film 44 to be removed and the concentration of the treatment liquid such as chromic acid / phosphoric acid. From the viewpoint of productivity, it is preferably 15 to 300 minutes.
(Step (c)):
In the step (c), the aluminum substrate 30 from which at least a part of the oxide film 44 has been removed is anodized again in the electrolytic solution to form the oxide film 44 having the pores 42. In the step (b), when all of the oxide film 44 is removed, the pores 42 regularly arranged starting from the pore generation points 46 can be formed.

Anodization may be performed under the same conditions as in step (a) or may be performed by appropriately changing the conditions. Deeper pores can be obtained as the anodic oxidation time is lengthened.
(Step (d)):
In the step (d), a process of expanding the diameter of the pores 42 of the oxide film 44 formed in the process (c) (hereinafter referred to as “pore diameter expanding process”) is performed. The pore diameter expansion process is a process of expanding a diameter of the pores 42 obtained by anodic oxidation by immersing the oxide film 44 in a solution for dissolving the oxide film 44 and dissolving a part of the oxide film 44. 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)):
In the step (e), the anodization in the step (c) and the pore diameter enlargement process in the step (d) are repeated. Then, anodized alumina having pores 42 whose diameter continuously decreases in the depth direction from the opening is formed, and a roll-shaped mold 50 having anodized alumina on the surface of the aluminum substrate 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 fine uneven structure manufactured using anodized alumina having such pores is insufficient. There is a case.

  A plurality of fine pores (concave portions) are formed on the surface of the mold body thus produced, thereby forming a fine concavo-convex structure. As the shape of the concave portion of the fine concavo-convex structure, there is a shape in which the cross-sectional area of the concave portion in a direction perpendicular to the depth direction, such as a cone shape, a bell shape, or a sharp shape, decreases continuously or stepwise from the outermost surface in the depth direction. preferable.

  20 nm or more and 400 nm or less are preferable, and, as for the average space | interval of the adjacent recessed part of a concavo-convex structure, 40 nm or more and 250 nm or less are more preferable. Since the visible light is scattered when the average interval between adjacent concave portions is larger than 400 nm, the transparency may be lowered when a molded body in which a fine uneven structure is transferred using a roll mold is used as an antireflection article. When the average interval between adjacent recesses is 25 nm or less, it may be difficult to transfer the fine relief structure.

  Moreover, it is preferable that the average depth of a recessed part is 100-500 nm, and 150-400 nm is more preferable. When the depth of the recess is 100 nm or less, the antireflection performance may be deteriorated when a molded body obtained by transferring the fine concavo-convex structure using a roll mold is used as an antireflection article. When the depth of the concave portion exceeds 500 nm, the mechanical properties of the fine concavo-convex structure may be deteriorated in the molded body produced using the roll-shaped mold.

In addition, in the manufacturing method of the roll-shaped mold of this invention, it is not necessary to implement all the above-mentioned process (a)-process (e), and when high regularity is not required, process (c)-process ( Only e) may be performed.
<Removal of aluminum substrate from treatment tank>
Here, when the aluminum substrate is transported between the steps (a) to (e), the electrolytic solution used for anodic oxidation or a treatment solution such as a solution used for dissolving at least a part of the oxide film is used. It is necessary to discharge (take out) the immersed aluminum base material from the liquid and transport the aluminum base material to the next step. When the aluminum base material is taken out from such a liquid, the treatment liquid adhering to the surface of the aluminum base material flows downward in the gravitational direction, and concentrates and stays below the aluminum base material in the gravitational direction (region in FIG. 9). S). As the electrolytic solution, a strong acid such as sulfuric acid, oxalic acid, or phosphoric acid is often used. Therefore, when a predetermined time elapses while the electrolytic solution is concentrated in the region S, the shape of the fine uneven structure in the region S is changed. It may change. In the present invention, after the aluminum substrate is taken out of the treatment tank, the electrolyte solution and the treatment solution are concentrated on a specific region of the aluminum substrate surface, such as below in the direction of gravity, for a predetermined time. A state that affects the flow rate is referred to as “stagnation” of the electrolytic solution or the processing solution.

  In particular, after the steps (b) and (d), which are steps for dissolving at least part of the oxide film, in the transportation of the aluminum base material to the next step, there is an influence on the shape of the fine uneven structure in the region S. growing.

  Therefore, in the present invention, the aluminum substrate is taken out from the treatment tank so that the treatment liquid does not concentrate and stay below the surface of the aluminum substrate in the direction of gravity. Below, the specific method is demonstrated, illustrating a pore diameter expansion process.

  FIG. 2 is a cross-sectional view showing an example of a pore diameter enlargement processing apparatus.

  The pore diameter enlargement processing apparatus 10 includes a pore diameter enlargement tank 12 filled with a treatment liquid, and a flange 14 for covering the upper portion of the pore diameter enlargement tank 12 and receiving the treatment liquid overflowing from the pore diameter enlargement tank 12. The upper cover 16 formed in the tank, the storage tank 18 for temporarily storing the processing liquid, the flow-down flow path 20 for flowing the processing liquid received by the collar part 14 to the storage tank 18, and the processing liquid in the storage tank 18 are made of aluminum. A return flow path 24 that returns to the supply port 22 formed near the bottom of the pore diameter expansion tank 12 below the base material 30, a pump 26 provided in the middle of the return flow path 24, and the supply port 22 A flow straightening plate 28 that adjusts the flow of the processing liquid discharged from the substrate, an axis 34 that is inserted into the hollow cylindrical aluminum base material 30 and the center axis 31 is held horizontally, and a center axis 31 ( That is, it is centered on the aluminum base material 30. ) Having a drive device for rotating the axis 34 and aluminum substrate 30 (not shown), and a temperature adjustment means 40 for adjusting the temperature of the process liquid in the storage tank 18 as a rotation axis.

  The pump 26 forms a flow of the processing liquid from the storage tank 18 through the return flow path 24 toward the pore diameter expansion tank 12 and discharges the processing liquid with a momentum from the supply port 22, thereby expanding the pore diameter. A flow of the processing liquid rising from the bottom to the top of the tank 12 is formed.

  The rectifying plate 28 is a plate-like member having a plurality of through holes that adjust the flow of the processing liquid so that the processing liquid discharged from the supply port 22 rises almost uniformly from the entire bottom of the pore diameter expansion tank 12. It is arrange | positioned between the aluminum base material 30 and the supply port 22 so that the surface may become substantially horizontal.

  The drive device (not shown) is a ring-shaped chain or a motor connected to the central shaft 31 of the shaft center 34 by a member (not shown) such as a gear.

  Examples of the temperature adjustment means 40 include a heat exchanger using water, oil, or the like as a heat medium, an electric heater, or the like.

  The pore diameter expansion process of the aluminum substrate 30 using the pore diameter expansion processing apparatus 10 is performed as follows, for example.

  In a state where the aluminum base material 30 is immersed in the treatment liquid of the pore diameter enlargement tank 12, the driving device (not shown) is driven to rotate the central axis 31 of the axis 34 (that is, the central axis of the aluminum base material 30). The axis 34 and the aluminum substrate 30 are rotated as axes.

  While rotating the aluminum base material 30, the pore diameter expansion process of the aluminum base material 30 is performed in a state of being immersed in the processing liquid.

  While performing the pore diameter expansion process of the aluminum base material 30, while discharging the part of the processing liquid from the pore diameter expansion tank 12 while rotating the aluminum base material 30, the same amount of the processing liquid is supplied to the pore diameter expansion tank 12. Supply. Specifically, after the treatment liquid is overflowed from the pore diameter expansion tank 12, the overflowed treatment liquid is caused to flow down to the storage tank 18, and the temperature of the treatment liquid is adjusted in the storage tank 18. It returns to the inside of the pore diameter expansion tank 12 from the supply port 22 provided below 30. At this time, the treatment liquid is discharged from the supply port 22 by the pump 26, and the treatment liquid discharged from the supply port 22 by the rectifying plate 28 rises almost uniformly from the entire bottom of the pore diameter expansion tank 12. By adjusting the flow of the processing liquid, a substantially uniform flow of the processing liquid rising from the bottom to the top of the anodizing tank 12 is formed.

  The supply amount of the treatment liquid to the pore diameter expansion tank 12 (discharge amount of the treatment liquid from the supply port 22) is preferably 41 L / min or more. If the supply amount of the treatment liquid is 41 L / min or more, a sufficient flow of the treatment liquid is generated in the entire pore diameter expansion tank 12. From the viewpoint of the capacity of the pump 26, the supply amount of the processing liquid is preferably 55 L / min or less.

  The number of rotations of the aluminum substrate 30 is preferably 3 rpm or more. If the rotation speed of the aluminum base material 30 is 3 rpm or more, the density | concentration of the process liquid in the circumference | surroundings of the aluminum base material 30 and the nonuniformity of temperature are fully suppressed. The rotational speed of the aluminum base 30 is preferably 10 rpm or less from the viewpoint of the capability of the driving device.

  After a predetermined processing time has elapsed, the aluminum base 30 is pulled up from the processing liquid by a vertical drive device (not shown). In the present invention, the aluminum base material 30 is taken out of the processing liquid so that the processing liquid does not stay at the same location on the bottom surface of the aluminum base material 30.

  In one embodiment of the present invention, the aluminum substrate 30 is discharged from the treatment liquid while rotating. When the aluminum substrate is taken out in this way, the treatment liquid remaining on the surface of the aluminum substrate does not concentrate and stay on a specific portion of the surface of the aluminum substrate. Therefore, as shown in the region S in FIG. 5, the occurrence of variations in the height of the fine concavo-convex structure on a part of the transfer surface is suppressed. The number of rotations of the aluminum substrate 30 at the time of discharging may be any as long as the treatment liquid does not scatter around, but is preferably 3 rpm or more. If the rotation speed of the aluminum base material 30 is 3 rpm or more, the aluminum base material 30 does not stay in the same location. The rotational speed of the aluminum base 30 is preferably 10 rpm or less from the viewpoint of the capability of the driving device. In addition, it is not necessary to rotate the aluminum substrate in the entire process of taking out the aluminum substrate from the treatment liquid, and the aluminum substrate may be rotated for a predetermined time after the entire aluminum substrate is discharged from the treatment liquid. . Such an aspect is also included in “take out from the processing liquid while rotating the aluminum base material”.

  In one embodiment of the present invention, when the aluminum substrate 30 is pulled up from the treatment liquid, a liquid such as cleaning water and a gas such as air are discharged from the treatment liquid from the nozzle 36 while being blown onto the aluminum substrate. The washing water or air is preferably sprayed toward the bottom of the aluminum substrate. When supplying cleaning water or air, it is not necessary to rotate the aluminum substrate 30, but from the viewpoint of supplying air or cleaning water evenly to the surface of the aluminum substrate, the aluminum substrate 30 is taken out from the processing liquid while rotating. It is preferable to spray air or a processing liquid from the nozzle 36. Moreover, you may spray both air and a process liquid simultaneously.

  In one embodiment of the present invention, as shown in FIG. 3, the aluminum base material 30 is discharged from the processing liquid in a state where the central axis 31 of the main body of the aluminum base material 30 is inclined with respect to the horizontal plane. . When the aluminum base material 30 is taken out in this way, the aluminum base material 30 is inclined, so that the treatment liquid remaining on the surface of the aluminum base material is processed to the end of the surface of one end of the main body (that is, processed to the end). Concentrate on the part touching the liquid). Therefore, as shown in FIG. 4, the region S in which the variation in the height of the fine concavo-convex structure caused by the liquid residue occurs at one place on the surface (non-transfer portion 12) of the end of the roll mold 50, It is possible to prevent variations in height on the center surface (transfer portion 13). In transfer by the roll-to-roll method, the central surface (transfer portion 33) of the roll-shaped mold 50 is used for transfer, and the end surface (non-transfer portion 32) is not used for transfer. Therefore, even if height variations occur in the non-transfer portion 32, there is no possibility of affecting the performance of the molded product.

Further, the aluminum base 30 may be taken out from the processing tank 12 while the central axis 31 of the main body of the aluminum base 30 is inclined with respect to the horizontal plane and the aluminum base 30 is rotated around the central axis 31. Thus, when the aluminum base material 30 is taken out, it can prevent more effectively that the variation in the height of a fine concavo-convex structure generate | occur | produces. Further, in a state where the central axis 31 of the main body of the aluminum base material 30 is inclined with respect to the horizontal plane, the aluminum base material 30 is taken out from the processing liquid while rotating, and air or cleaning water is sprayed on the rotating aluminum base material 30. Also good. When the aluminum base material 30 is taken out in this way, it is possible to more effectively prevent the treatment liquid such as the electrolytic solution and the etchant remaining on the surface of the aluminum base material 30 from being concentrated on one place on the surface of the aluminum base material. .
<Method using a mixed solution of electrolyte and etchant>
In one embodiment of the present invention, the mold manufacturing method includes the following steps (1) to (4). In the following method, since the anodization and the pore diameter expansion treatment can be performed in the same tank, the number of times the aluminum substrate is taken out from the treatment liquid can be reduced, and the gravity of the surface of the aluminum substrate can be reduced. It is possible to suppress the occurrence of variations in the height of the fine uneven structure in the lower direction. The method will be described below.

  Step (1): A step of immersing the aluminum substrate in an electrolytic solution in which a plurality of acids are mixed.

  Step (2): A step of applying a voltage to the aluminum substrate immersed in the electrolytic solution.

  Step (3): A step of holding the aluminum base material while being immersed in the electrolytic solution without substantially applying a voltage to the aluminum base material.

Step (4): A step of alternately repeating the step (2) and the step (3).
(Process (1))
In the mold manufacturing method of the present invention, step (1) is a step of immersing the aluminum substrate in an electrolytic solution in which a plurality of acids are mixed.

  The aluminum base material used in the step (1) may be the same as in the above step (a).

  As the electrolytic solution for immersing the aluminum base material used in the steps (1) to (4), a mixture of a plurality of acids is used. In the present invention, “a plurality of acids” means an acid that contributes to the formation of an oxide film (hereinafter also referred to as “first acid”) and at least a part of the oxide film, and is formed on the oxide film. It refers to a combination with an acid (hereinafter sometimes referred to as “second acid”) useful for pore diameter enlargement treatment for expanding the pores formed.

  The plurality of acids are preferably at least two acids selected from sulfuric acid, phosphoric acid, oxalic acid, malonic acid, tartaric acid, succinic acid, malic acid, and citric acid.

  Here, examples of the first acid include oxalic acid and sulfuric acid, and examples of the second acid include phosphoric acid.

  In steps (1) to (4), by using such a mixture of two or more acids as an electrolytic solution, anodizing treatment and pore diameter expansion treatment on the surface of the aluminum substrate are performed in one tank. Therefore, the work of removing the aluminum base material from the treatment liquid and immersing it in the treatment liquid of another tank after completion of the anodization process or after completion of the pore diameter enlargement process becomes unnecessary. Simplification is possible. Furthermore, the frequency | count which takes out an aluminum base material from a process liquid can be reduced, and it can suppress that the dispersion | variation in the height of a fine concavo-convex structure generate | occur | produces below the gravity direction of the aluminum base material surface.

  As the plurality of acids, a combination of oxalic acid and phosphoric acid is preferable. It is preferable to use oxalic acid and phosphoric acid as the plurality of acids because highly regular pores are easily formed on the surface of the aluminum substrate and the shape of the pores can be easily controlled.

  As a method for determining the composition of the electrolytic solution in which a plurality of acids are mixed, it is preferable to first determine the first acid and the second acid and determine the concentration of each acid according to the temperature during anodization.

  For example, when the first acid is sulfuric acid, the second acid is phosphoric acid, and the temperature of the electrolytic solution when anodizing is 30 ° C. or lower, preferably 20 ° C. or lower, sulfuric acid in the electrolytic solution The concentration of is preferably 0.7M or less, and more preferably 0.05 to 0.7M. If the concentration of sulfuric acid in the electrolyte exceeds 0.7M, the current value may become too high to maintain a constant voltage. On the other hand, the concentration of phosphoric acid in the electrolytic solution is preferably 3M or less, and more preferably 0.02 to 3M. It is preferable that the concentration of phosphoric acid in the electrolytic solution is 3M or less because the pore diameter expansion rate can be easily controlled.

  In addition, for example, when the first acid is oxalic acid, the second acid is phosphoric acid, and the temperature of the electrolytic solution when anodizing is 4 ° C. or higher and lower than 20 ° C., oxalic acid in the electrolytic solution The concentration of is preferably 0.05M or more and 1M or less. If the concentration of oxalic acid in the electrolytic solution is 1 M or less, it is preferable because the current value becomes too high and the surface of the oxide film can be prevented from becoming rough. The concentration of phosphoric acid in the electrolytic solution is preferably 5M or less, more preferably 0.05 to 5M, and still more preferably 0.1 to 3M. It is preferable that the concentration of phosphoric acid in the electrolytic solution is 5 M or less because the pore diameter expansion rate can be easily controlled.

  When the temperature of the electrolytic solution during the anodic oxidation is 20 ° C. or higher and lower than 35 ° C., the concentration of oxalic acid in the electrolytic solution is preferably 1M or less, and more preferably 0.05 to 1M. If the concentration of oxalic acid in the electrolytic solution is 1 M or less, it is preferable because the current value becomes too high and the surface of the oxide film can be prevented from becoming rough. The concentration of phosphoric acid in the electrolytic solution is preferably 0.3M or less, more preferably 0.02 to 0.3M, and still more preferably 0.05 to 0.3M. A concentration of phosphoric acid in the electrolytic solution of 0.3 M or less is preferable because the pore diameter expansion rate can be easily controlled.

In the present invention, the mixing ratio of the first acid and the second acid in the electrolytic solution in which a plurality of acids are mixed is 1
: 9-9: 1 are preferable. If the mixing ratio of the first acid and the second acid in the electrolyte mixed with a plurality of acids is 1: 9 to 9: 1, highly regular pores are formed on the surface of the aluminum substrate. It is preferable because it is easy and control of the shape of the pores is easy.
(Step (2)):
In the mold manufacturing method of the present invention, step (2) is a step of applying a voltage to the aluminum substrate immersed in an electrolytic solution in which a plurality of acids are mixed. That is, the step (2) is a step of anodizing the aluminum substrate in an electrolytic solution in which a plurality of acids are mixed.

  By immersing a part or all of the surface of the aluminum base material in the electrolytic solution and performing anodic oxidation, an oxide film can be formed on the portion immersed in the electrolytic solution in which a plurality of acids are mixed.

  The composition and temperature of the electrolytic solution in which a plurality of acids are mixed affect the depth of the pores during anodization and the pore diameter expansion rate during the pore diameter expansion treatment. In the present invention, when the concentration of the second acid in the electrolyte mixed with a plurality of acids is increased, or when the temperature of the electrolyte mixed with a plurality of acids is increased, the speed of expansion of the pore diameter is increased and the time is shortened. The pores can be enlarged. On the other hand, control of the pore diameter becomes difficult as the enlargement speed increases. Accordingly, in order to form pores having a desired shape and pore diameter on the surface of the aluminum base material, the concentration of a plurality of acids in the electrolyte mixed with a plurality of acids and the plurality of acids were mixed. It is important to control the temperature of the electrolyte.

  In the step (2), the voltage applied to the aluminum substrate is preferably 40 to 180V. In the step (b), it is preferable that the voltage applied to the aluminum substrate is 40 V or higher because an oxide film having a pore interval exceeding 100 nm can be easily formed. In addition, if the voltage applied to the aluminum substrate is 180 V or less, there is no need to use a device for maintaining the electrolyte at a low temperature or a special technique such as injecting a cooling liquid on the back surface of the aluminum substrate. Since it can anodize with an apparatus, it is preferable.

  In step (2), the voltage applied to the aluminum substrate may be constant from the beginning to the end of the anodizing step, or may be changed in the middle. When changing the voltage in the middle, the voltage may be increased stepwise or the voltage may be increased continuously.

  Moreover, when the current density immediately after applying a voltage to an aluminum base material will be 10 mA / cm <2> or less, you may apply the highest voltage of 40V or more from the beginning. Alternatively, the initial anodic oxidation may be performed at a voltage of less than 40V, the voltage may be increased stepwise or continuously, and the voltage may be finally adjusted to be in the range of 40 to 180V. Here, the “maximum voltage” means the maximum value of the voltage in the step (2) and coincides with the voltage at the end of the step (2).

  When the voltage is increased stepwise, the voltage may be held for a certain period of time, or the voltage may be temporarily decreased. Further, the voltage may be increased continuously over time so that the voltage boosting rate is 0.05 to 5 V / s.

  When the voltage is temporarily reduced, the voltage may be temporarily 0V. However, when the voltage becomes 0V during the anodic oxidation, the electric field applied to the anode is eliminated. Therefore, when the voltage is raised and the electric field is applied again after the voltage becomes 0 V in the middle, the aluminum base material and the oxide film may be partially separated, and the thickness of the oxide film may become uneven. . Therefore, it is preferable to perform anodization so that the voltage does not become 0 V in the middle.

  Here, “fixed time” means 1 to 10 minutes.

Further, the boosting speed when boosting from an arbitrary voltage to the next voltage is not particularly limited, and the voltage may be boosted instantaneously or gradually. However, when the voltage is rapidly increased, the current density flowing in the aluminum base material may increase instantaneously and burns may occur. On the other hand, if the boosting speed is too slow, the oxide film may be formed thick while the voltage is increased. Therefore, the voltage boosting speed is preferably 0.05 to 5 V / s. The same applies to the boosting speed when the voltage is continuously increased.

  In the step (2), the time for applying the voltage to the aluminum substrate to perform anodization is preferably 3 to 600 seconds, and more preferably 30 to 120 seconds. If the time for applying a voltage to the aluminum substrate is 3 to 600 seconds, it is preferable because the thickness of the oxide film on the surface of the aluminum substrate can be easily controlled to 0.01 to 0.8 μm described later.

If the thickness of the oxide film on the surface of the aluminum substrate is less than 0.01 μm, the depth of the pores is less than 0.01 μm, so that when used as a mold, the resulting molded product may not exhibit sufficient antireflection performance There is. When the thickness of the oxide film exceeds 0.8 μm, the pores become deeper as the oxide film becomes thicker, so that when used as a mold, there is a risk of causing a mold release failure.
(Step (3)):
In the method for producing a mold of the present invention, the step (3) is a step of holding the aluminum substrate immersed in an electrolytic solution in which a plurality of acids are mixed without substantially applying a voltage to the aluminum substrate. It is. In the present invention, the application of voltage is interrupted after the step (2), and the aluminum substrate is held in an electrolytic solution in which a plurality of acids are mixed in the same reaction tank, thereby forming an oxide film. The pores can be expanded. Thus, according to the mold manufacturing method of the present invention, the anodization of the aluminum base and the pore diameter expansion treatment can be performed in one reaction tank. Therefore, it is not necessary to carry out the pore diameter expansion process by pulling it up and dipping in another tank, and the manufacturing process and the apparatus can be simplified. Furthermore, it can suppress that the electrolyte solution adhering to the surface of an aluminum base material concentrates below a gravitational direction, and the dispersion | variation in the height of a fine concavo-convex structure generate | occur | produces.

  In the present invention, after the application of voltage to the aluminum substrate is interrupted, the longer the time for which the aluminum substrate is kept immersed in the electrolyte mixed with a plurality of acids, the larger the pore diameter becomes. Become. In the present invention, “interrupting the application of voltage” or “not applying a voltage substantially” means not only that the voltage applied to the aluminum substrate is 0 V, but also that the current is applied to the substrate. This includes reducing the voltage to such an extent that it does not flow and the formation of the anodized film does not proceed.

  In the step (3), the temperature of the electrolytic solution when the aluminum substrate is kept immersed in the electrolytic solution mixed with a plurality of acids is preferably 5 to 40 ° C, more preferably 10 to 35 ° C. It is preferable that the temperature of the electrolytic solution is 5 to 40 ° C. because the speed of the pore diameter expansion treatment can be controlled and the pores can be more easily tapered.

  In the step (3), the time for immersing the aluminum base material in the electrolytic solution in which a plurality of acids are mixed (hereinafter referred to as “immersion time”) can be appropriately adjusted depending on the composition and temperature of the electrolytic solution. For example, the immersion time when the concentration of the second acid in the electrolytic solution in which a plurality of acids are mixed is 0.5 M and the temperature of the electrolytic solution is 20 ° C. or higher and lower than 35 ° C. is 15 to 200 minutes. Preferably, 30 to 120 minutes are more preferable. When the immersion time exceeds 200 minutes, it is not preferable in terms of production efficiency. Moreover, the pore diameter enlargement process is performed excessively, and tapered pores may not be obtained. On the other hand, when the immersion time is less than 15 minutes, the pores may not be tapered. That is, it is preferable that the immersion time is 15 to 200 minutes, because the pores having a tapered shape can be efficiently formed.

  When the concentration of the second acid in the electrolytic solution in which a plurality of acids are mixed is relatively low, that is, when the concentration is 0.05 M or more and less than 0.5 M, the progress of pore diameter expansion tends to be slow. In such a case, the immersion time can be increased and / or the temperature of the electrolytic solution can be increased. When the concentration of the second acid in the electrolyte mixed with a plurality of acids is 0.05 M or more and less than 0.5 M and the temperature of the electrolyte is less than 20 ° C., the immersion time is preferably 30 minutes or more and 200 minutes or less. 45 minutes or more and 180 minutes or less is more preferable.

When the concentration of the second acid in the electrolytic solution in which a plurality of acids are mixed is 0.05 M or more and less than 0.5 M and the temperature of the electrolytic solution is 20 ° C. or more and less than 35 ° C., the immersion time is 30 to 180 minutes. Preferably
45-160 minutes is more preferable.

  On the other hand, when the concentration of the second acid in the electrolytic solution in which a plurality of acids are mixed is relatively high, that is, when the concentration is 0.5 M or more and 5 M or less, the progress of pore diameter expansion tends to be accelerated. In such a case, the immersion time can be shortened and / or the temperature of the electrolytic solution can be lowered.

  When the concentration of the second acid in the electrolytic solution in which a plurality of acids are mixed is 0.5 M or more and the temperature of the electrolytic solution is less than 20 ° C., the immersion time is preferably 15 minutes or more and 200 minutes or less, 30 minutes More preferably, it is 120 minutes or less.

When the concentration of the second acid in the electrolyte mixed with a plurality of acids is 0.5 M or more and the temperature of the electrolyte is 20 ° C. or more and 35 ° C. or less, the immersion time is preferably 10 minutes or more and 120 minutes or less. 20 minutes or more and 100 minutes or less is more preferable.
(Process (4))
In the method for producing a roll mold of the present invention, the step (4) is a step of alternately repeating the step (2) and the step (3).

  The number of times the step (4) is performed, that is, the number of repetitions of the step (2) and the step (3) is three times in total because the larger the number, the smoother the pores can be made. The above is preferable, and 5 times or more is more preferable. Further, the upper limit of the number of repetitions of step (2) and step (3) is preferably 10 times or less from the viewpoint of production efficiency. When the total number of repetitions of step (b) and step (c) is 2 or less, the pore diameter of the pores decreases discontinuously. When a prevention film or the like is manufactured, the reflectance reduction effect may be insufficient.

  The step (4) may be terminated in the step (2) or may be terminated in the step (3). However, from the viewpoint of forming a tapered shape in which the pore diameter of the formed pores continuously changes, It is preferable to end in the step (3). Since the pores have a tapered shape, the refractive index can be continuously increased, the fluctuation of reflectance due to wavelength (wavelength dependence) can be suppressed, and the scattering of visible light can be suppressed to achieve a low reflectance. It is preferable because the effect is obtained.

  In the mold manufacturing method of the present invention, the step (a) and the step of removing at least a part of the anodic oxide film using the chromic acid / phosphoric acid mixed solution or the like are used before the step (1). (B) may be performed separately.

In this embodiment, since anodization and pore diameter enlargement processing are performed in the same tank, the transport of the aluminum base material is performed each time from step (3), which is a step of dissolving the anodized film, to step (2). It is unnecessary. Accordingly, the treatment liquid such as the electrolytic solution and the etchant remaining on the surface of the aluminum base material remains in one place such as the region S on the surface of the aluminum base material, and the occurrence of variations in the height of the fine concavo-convex structure is suppressed. . Moreover, in this embodiment, when taking out an aluminum base material from a process liquid, an aluminum base material is taken out from a process liquid by the method similar to the above-mentioned. As a result, the treatment liquid such as the electrolytic solution and the etchant remaining on the surface of the aluminum base material is left in one place such as the region S on the surface of the aluminum base material, and the occurrence of variation in the height of the fine concavo-convex structure is suppressed. be able to.
<Mold>
According to the method for producing a roll-shaped mold of the present invention, the occurrence of variation in the height of the fine uneven structure on the surface is suppressed, and the diameter gradually decreases in the depth direction from the opening to the surface of the aluminum substrate. Thus, it is possible to manufacture a mold in which tapered pores are regularly arranged and formed, and as a result, an oxide film having a plurality of pores is formed on the surface of the aluminum substrate.

  The interval between the pores in the roll mold of the present invention is preferably not more than the wavelength of visible light, preferably 20 to 400 nm, and more preferably 40 to 250 nm. If the interval between the pores is 20 nm or more, the scratch resistance can be improved without impairing the antireflection performance of a molded body (such as an antireflection article) obtained by transferring the surface of the mold of the present invention. If the gap between the pores is 400 nm or less, the surface of the molded body (transfer surface) obtained by transferring the surface of the mold is less likely to scatter visible light, and a sufficient antireflection function is exhibited. Suitable for manufacturing anti-reflective articles such as films.

  Moreover, when using a roll-shaped mold for manufacture of an antireflection article (antireflection film etc.), it is preferable that the space | interval of a pore is 400 nm or less, and the depth of a pore is 100 nm or more, and is 150 nm or more. It is more preferable. When a mold having a pore depth of less than 100 nm is used, the antireflection performance of the antireflection article may be insufficient, which is not preferable. The upper limit of the depth of the pores is preferably 500 nm or less, and more preferably 400 nm or less. If the depth of the pore is 500 nm or less, it is preferable in the formed antireflection article because the mechanical strength of the projection having the inverted shape of the pore can be maintained. That is, the depth of the pores when the mold is used for manufacturing an antireflection article (antireflection film or the like) is preferably 100 to 500 nm, and more preferably 150 to 400 nm.

  The aspect ratio (pore depth / pore interval) of the mold pores is preferably 0.25 or more, more preferably 0.5 or more, and most preferably 0.75 or more. When the aspect ratio is 0.25 or more, a surface with low reflectance can be formed, and the incident angle dependency thereof is sufficiently small. In addition, the upper limit of the aspect ratio of the pores of the mold is preferably 4 or less from the viewpoint of maintaining the mechanical strength of the protrusion having the inverted shape of the pores.

The surface of the mold on which the oxide film having a plurality of pores is formed may be subjected to a release treatment so that the release is easy. Examples of the release treatment method include a method of coating a phosphate ester polymer, a silicone polymer, a fluorine polymer, a method of depositing a fluorine compound, a coating of a fluorine surface treatment agent or a fluorine silicone surface treatment agent. Methods and the like.
<Method for producing article having fine concavo-convex structure on surface>
The method for producing an article having a fine concavo-convex structure on the surface thereof according to the present invention includes a fine concavo-convex structure comprising a plurality of pores formed on the surface of a roll mold obtained by the roll mold production method of the present invention, This is a method of transferring to the surface of the article body.

  In an article produced by transferring the fine uneven structure (pores) of the roll-shaped mold, the reverse structure (convex portion) of the fine uneven structure of the roll mold is transferred on the surface in a relationship between the key and the keyhole.

As a method for transferring the fine concavo-convex structure of the roll-shaped mold to the surface of the article main body, for example, an uncured active energy ray-curable resin composition is filled between the roll-shaped mold and the transparent substrate (article main body), A method of releasing the roll mold after irradiating the active energy ray curable resin composition by irradiating the active energy ray with the active energy ray curable resin composition in contact with the fine uneven structure of the roll mold Is preferred. Thereby, an article in which a fine uneven structure made of a cured product of the active energy ray-curable resin composition is formed on the surface of the transparent substrate can be produced. The fine uneven structure of the obtained article is an inverted structure of the fine uneven structure of the roll mold.
<Article body>
As a transparent base material (base film), since active energy ray irradiation is performed through the transparent base material, a material that does not significantly impede irradiation of active energy rays is preferable. Examples of the material for the transparent substrate include polyester resins (polyethylene terephthalate, polybutylene terephthalate, etc.), polymethacrylate resins, polycarbonate resins, vinyl chloride resins, ABS resins, styrene resins, and glass.
<Active energy ray-curable resin composition>
Since the method using the active energy ray-curable resin composition does not require heating or cooling after curing as compared with the method using the thermosetting resin composition, the fine uneven structure can be transferred in a short time, Suitable for mass production.

  As a filling method of the active energy ray-curable resin composition, a method of filling the active energy ray-curable resin composition between the roll-shaped mold and the transparent substrate and then rolling and filling it, an active energy ray-curable resin composition Examples thereof include a method of laminating a transparent substrate on a roll-shaped mold coated with a product, a method of previously laminating an active energy ray-curable resin composition on a transparent substrate, and laminating on a roll-shaped mold.

  The active energy ray-curable resin composition contains a polymerization reactive compound and an active energy ray polymerization initiator. In addition to the above, a non-reactive polymer or active energy ray sol-gel reactive component may be contained depending on the application, and a thickener, leveling agent, ultraviolet absorber, light stabilizer, heat stabilizer, solvent Various additives such as inorganic fillers may be included.

  Examples of the polymerization reactive compound include monomers, oligomers, and reactive polymers having a radical polymerizable bond and / or a cationic polymerizable bond in the molecule.

  Examples of the monomer having a radical polymerizable bond include a monofunctional monomer and a polyfunctional monomer.

  Monofunctional monomers having a radical polymerizable bond include (meth) acrylate derivatives (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, hydroxypropyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, etc.), (meth) acrylic acid, ( (Meth) acrylonitrile, styrene derivatives (styrene, α-methylstyrene, etc.), (meth) acrylamide derivatives ((meth) acrylamide, N-dimethyl (meth) acrylamide, N-diethyl (meth) acrylamide, dimethylaminopropyl (meth) acrylamide Etc.). These may be used alone or in combination of two or more.

  As the polyfunctional monomer having a radical polymerizable bond, bifunctional monomers (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) acryloxyethoxy) Nyl) propane, 2,2-bis (4- (3- (meth) 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 of bisphenol A di (meth) acrylate, propylene oxide adduct of bisphenol A Di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, divinylbenzene, methylenebisacrylamide, etc.), trifunctional monomers (pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate) , Trimethylolpropane ethylene oxide modified tri (meth) acrylate, trimethylolpropane propylene oxide modified triacrylate, trimethylolpropane ethylene oxide modified triacrylate, isocyanuric acid ethylene oxide modified tri (meth) acrylate, etc.), tetrafunctional or higher monomer ( Condensation reaction mixture of succinic acid / trimethylolethane / acrylic acid, dipentaerystol hexa (meth) acrylate, dipentaerystol penta (meth) acrylate, ditrimethylolpropane tetraacrylate, tetramethylolmethane tetra (meth) acrylate, etc.) , Bifunctional or higher urethane acrylate, bifunctional or higher polyester acrylate, 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 having a radical polymerizable bond and / or a cationic polymerizable bond in the molecule include unsaturated polyesters such as a condensate of unsaturated dicarboxylic acid and polyhydric alcohol; polyester (meth) acrylate, poly Ether (meth) acrylate, polyol (meth) acrylate, epoxy (meth) acrylate, urethane (meth) acrylate, cationic polymerization type epoxy compound, homopolymer or copolymer of the above-mentioned monomers having a radical polymerizable bond in the side chain, etc. Can be mentioned.

  As the active energy ray polymerization initiator, a known polymerization initiator can be used, and it is preferable to select appropriately according to the type of active energy ray used when the active energy ray curable resin composition is cured.

  When using a photocuring reaction, photopolymerization initiators include carbonyl compounds (benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzyl, benzophenone, p-methoxybenzophenone, 2,2-di- Ethoxyacetophenone, α, α-dimethoxy-α-phenylacetophenone, methylphenylglyoxylate, ethylphenylglyoxylate, 4,4′-bis (dimethylamino) benzophenone, 2-hydroxy-2-methyl-1-phenylpropane -1-one), sulfur compounds (tetramethylthiuram monosulfide, tetramethylthiuram disulfide, etc.), 2,4,6-trimethylbenzoyldiphenylphosphine oxide, benzoyldi Butoxy phosphine oxide and the like. These may be used alone or in combination of two or more.

  When an electron beam curing reaction is used, polymerization initiators include benzophenone, 4,4-bis (diethylamino) benzophenone, 2,4,6-trimethylbenzophenone, methyl orthobenzoyl benzoate, 4-phenylbenzophenone, and t-butylanthraquinone. 2-ethylanthraquinone, thioxanthone (2,4-diethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, etc.), acetophenone (diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, Benzyldimethyl ketal, 1-hydroxycyclohexyl-phenylketone, 2-methyl-2-morpholino (4-thiomethylphenyl) propan-1-one, 2-benzyl-2-dimethylamino-1- (4 Morpholinophenyl) -butanone), benzoin ether (benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, etc.), acylphosphine oxide (2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,6) -Dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, etc.), methylbenzoylformate, 1,7-bisacridinylheptane, 9 -Phenylacridine and the like. These may be used alone or in combination of two or more.

  The content of the active energy ray polymerization initiator in the active energy ray curable resin composition is preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the polymerization reactive compound. When the active energy ray polymerization initiator is less than 0.1 part by mass, the polymerization is difficult to proceed. When the active energy ray polymerization initiator exceeds 10 parts by mass, the cured resin may be colored or the mechanical strength may be lowered.

  Non-reactive polymers include acrylic resins, styrene resins, polyurethane resins, cellulose resins, polyvinyl butyral resins, polyester resins, thermoplastic elastomers, and the like.

  Examples of the active energy ray sol-gel reactive component include alkoxysilane compounds and alkyl silicate compounds.

  Examples of the alkoxysilane compound include those represented by RxSi (OR ′) y. R and R ′ represent an alkyl group having 1 to 10 carbon atoms, and x and y are integers satisfying the relationship of x + y = 4. Specifically, tetramethoxysilane, tetra-iso-propoxysilane, tetra-n-propoxysilane, tetra-n-butoxysilane, tetra-sec-butoxysilane, tetra-tert-butoxysilane, methyltriethoxysilane, methyl Examples include tripropoxysilane, methyltributoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, trimethylethoxysilane, trimethylmethoxysilane, trimethylpropoxysilane, and trimethylbutoxysilane.

Examples of the alkyl silicate compound include those represented by R1O [Si (OR3) (OR4) O] zR2. R1 to R4 each represent an alkyl group having 1 to 5 carbon atoms, and z represents an integer of 3 to 20. Specific examples include methyl silicate, ethyl silicate, isopropyl silicate, n-propyl silicate, n-butyl silicate, n-pentyl silicate, acetyl silicate and the like.
<Manufacturing equipment>
An article having a fine concavo-convex structure on its surface is manufactured as follows using, for example, a manufacturing apparatus shown in FIG.

  A tank 54 is provided between a roll-shaped mold 50 in which anodized alumina having a plurality of pores is formed on the outer peripheral surface and a strip-shaped base film 52 (article body) that moves along the surface of the roll-shaped mold 50. The active energy ray-curable resin composition 56 is supplied.

  The base film 52 and the active energy ray curable resin composition 56 are nipped between the roll-shaped mold 50 and the nip roll 60 whose nip pressure is adjusted by the pneumatic cylinder 58, and the active energy ray curable resin composition 56. Is uniformly distributed between the base film 52 and the roll mold 50, and at the same time, the pores on the outer peripheral surface of the roll mold 50 are filled.

  Using an active energy ray irradiation device 62 installed below the roll-shaped mold 50 in a state where the active energy ray-curable resin composition 56 is sandwiched between the roll-shaped mold 50 and the base film 52, By irradiating the active energy ray-curable resin composition 56 with active energy rays from the material film 52 side and curing the active energy ray-curable resin composition 56, a plurality of pores on the outer peripheral surface of the roll-shaped mold 50 are formed. The transferred cured resin layer 64 is formed.

  An article 68 is obtained by peeling the base film 52 having the cured resin layer 64 formed on the surface from the roll-shaped mold 50 by the peeling roll 66.

As the active energy ray irradiation device 62, a high-pressure mercury lamp, a metal halide lamp, or the like is preferable. In this case, the amount of light irradiation energy is preferably 100 to 10,000 mJ / cm 2.
<Article>
An article 68 shown in FIG. 6 has a cured resin layer 64 formed on the surface of a substrate film 52 (transparent substrate).

  The cured resin layer 64 is a film made of a cured product of the active energy ray curable resin composition, and has a fine uneven structure on the surface.

  The fine concavo-convex structure on the surface of the article 68 when the roll-shaped mold in the present invention is used is formed by, for example, transferring the fine concavo-convex structure on the surface of the oxide film, and the active energy ray-curable resin composition. It has the some convex part 70 which consists of hardened | cured material.

  As the fine concavo-convex structure, 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 is preferable. It is known that the moth-eye structure in which the distance between the protrusions is less than or equal to the wavelength of visible light is an effective anti-reflection measure by continuously increasing the refractive index from the refractive index of air to the refractive index of the material. It has been.

  The article manufactured by the manufacturing method of the present invention exhibits various performances such as antireflection performance and water repellency performance by the fine uneven structure on the surface.

  When an article having a fine concavo-convex structure is a sheet or film, the surface of an object such as an image display device (TV, mobile phone display, etc.), display panel, meter panel, etc. is used as an antireflection film. It can be used by pasting it on or insert molding it. In addition, taking advantage of water repellency, it is also used as a member for objects that may be exposed to rain, water, steam, etc., such as bathroom windows and mirrors, solar cell members, automobile mirrors, signboards, glasses lenses, etc. be able to.

  When an article having a fine concavo-convex structure on its surface is a three-dimensional shape, an antireflection article is manufactured using a transparent substrate having a shape suitable for the application, and this is used as a member constituting the surface of the object. You can also

  When the object is an image display device, not only the surface thereof, but also an article having a fine uneven structure on the surface may be attached to the front plate, or the front plate itself may be It can also consist of an article having a structure on its surface. For example, an article having a fine concavo-convex structure on the surface of a rod lens array attached to a sensor array for reading an image, a cover glass of an image sensor such as a FAX, a copying machine or a scanner, or a contact glass for placing an original of a copying machine May be used. Further, by using an article having a fine concavo-convex structure on the surface of a light receiving portion of an optical communication device such as visible light communication, signal reception sensitivity can be improved.

  In addition to the uses described above, articles having a fine concavo-convex structure on the surface can be developed for optical uses such as optical waveguides, relief holograms, optical lenses, and polarization separation elements, and for use as cell culture sheets.

  In the method for manufacturing an article having a fine concavo-convex structure on the surface according to the present invention described above, since the roll-shaped mold obtained by the method for manufacturing a roll-shaped mold according to the present invention is used, the height of the convex portion is used. An article having a fine concavo-convex structure on the surface, in which variations in the above are suppressed, can be manufactured.

Hereinafter, the present invention will be specifically described by way of examples.
(Inspection of anodized alumina)
The surface of the anodized alumina is irradiated with light from the illumination unit, the reflected light from the surface of the anodized alumina is imaged by the imaging unit, color information is obtained from the image captured by the imaging unit, and the color information Based on the above, it was determined whether there was variation in the pores of the anodized alumina.
Example 1
A hollow cylindrical aluminum substrate (purity: 99.99%, length: 280 mm, outer diameter: 200 mm, inner diameter: 155 mm) was subjected to a feather polishing treatment, and then this was mixed in a perchloric acid / ethanol mixed solution ( Electropolishing was performed at a volume ratio = 1/4).

  Subsequently, the aluminum substrate is placed in a 107 L electrolytic solution composed of a 0.3 mol / L aqueous solution, bath temperature: 15.7 ° C., direct current: 40 V, supply amount of the electrolytic solution: 41 L / min, and the rotational speed of the aluminum substrate. : Anodized for 30 minutes under the condition of 6 rpm to form an oxide film (step (a)).

  The formed oxide film was once dissolved and removed in a 6% by mass phosphoric acid and 1.8% by mass chromic acid mixed aqueous solution (step (b)), and then again under the same conditions as in step (a). Anodized for 2 seconds to form an oxide film (step (c)).

  Thereafter, using the pore diameter enlargement processing apparatus 10, the pore diameter enlargement treatment (step (d)) is carried out by immersing in a 5 mass% phosphoric acid aqueous solution (31.7 ° C.) for 8 minutes to enlarge the pores of the oxide film. ). After the immersion time, the aluminum substrate was pulled up from the treatment liquid while rotating at 6 rpm.

  Further, the step (c) and the step (d) were repeated, and the step (c) was carried out 5 times in total and the step (d) was carried out 5 times in total (step (e)). A roll-shaped mold A was obtained in which anodized alumina having substantially conical tapered pores was formed on the outer peripheral surface of the aluminum base material. The obtained roll-shaped mold A was photographed with an imaging means, and it was determined whether there was variation in pores of the anodized alumina. The results are shown in FIG. 7 and 8 are images in which the outer peripheral surface of the cylindrical mold is imaged and developed.

  Subsequently, the roll mold A was dipped in a 0.1% by mass solution of a mold release agent (manufactured by Daikin Industries, Ltd., OPTOOL DSX (trade name)) for 10 minutes and air-dried for 24 hours to perform a mold release treatment.

  An article having a plurality of convex portions on the surface was produced using the production apparatus shown in FIG.

  As the roll mold 50, the roll mold A was used.

  As the active energy ray-curable resin composition 56, the active energy ray-curable resin composition A shown in Table 1 below was used.

As the base film 52, a polyethylene terephthalate film (manufactured by Toyobo Co., Ltd., trade name: A4300, thickness: 75 μm) was used.

  The active energy ray-curable resin composition A was cured by irradiating the active energy ray-curable resin composition A with ultraviolet rays having an integrated light amount of 1100 mJ / cm 2 from the base film 52 side.

As a result of visually observing the obtained article, no defect due to height unevenness was found.
(Comparative Example 1)
Anodized alumina having substantially conical tapered pores on the outer peripheral surface of the aluminum base material in the same manner as in Example 1 except that the aluminum base material is not rotated at the time of pulling up from the treatment liquid in the step (d). A roll-shaped mold B on which was formed was obtained. The obtained roll-shaped mold B was photographed with an imaging means, and it was determined whether there was variation in pores of the anodized alumina. The results are shown in FIG.

  Next, in the same manner as in Example 1, the mold release process of the roll mold B was performed.

  Next, an article having a plurality of convex portions on the surface was produced in the same manner as in Example 1 except that the roll mold B was used as the roll mold 50. As a result of visually observing the obtained article, periodic defects due to height unevenness were found.

  As can be seen from the fact that the roll-shaped mold A of Example 1 manufactured by pulling up while rotating the aluminum substrate after the pore diameter enlargement treatment shows little change in color shading in FIG. There was little variation in depth. As a result, even in an article having a plurality of convex portions on the surface, no variation in the height of the convex portions, that is, no defect was found.

  On the other hand, the roll-shaped mold B of Comparative Example 1 manufactured by pulling up without rotating the aluminum base material after the pore diameter expansion treatment has a pore depth as shown in FIG. There was a band-like region with a large variation in thickness. As a result, even in an article having a plurality of convex portions on the surface, variations in the height of the convex portions, that is, defects were found.

  The roll-shaped mold obtained by the roll-shaped mold manufacturing method of the present invention is useful when manufacturing an article having a fine concavo-convex structure on the surface by a roll-to-roll imprint method.

Pore diameter treatment device 10
Pore diameter expansion tank 12
Isobe 14
Top cover 16
Reservoir 18
Downstream channel 20
Supply port 22
Return flow path 24
Pump 26
Current plate 28
Aluminum substrate 30
Central axis 31
Non-transfer section 32
Transcription part 33
Axis 34
Pore 42
Oxide film 44
Pore generation point 46
Roll mold 50
Substrate film (transparent substrate) 52
Transcription part 53
Tank 54
Active energy ray-curable resin composition 56
Pneumatic cylinder 58
Nip roll 60
Active energy ray irradiation device 62
Cured resin layer 64
Article 68
Convex part 70
Area S

Claims (7)

In the method for producing a roll-shaped mold in which an oxide film having a plurality of pores is formed on the surface of an aluminum substrate,
(I) a step of anodizing an aluminum substrate in an electrolytic solution to form an oxide film having a plurality of pores; and (II) immersing the aluminum substrate in a treatment solution to at least part of the oxide film The step of dissolving,
After at least one of the steps (I) and (II), at least one of the electrolytic solution and the processing solution is not accumulated in the lower part of the aluminum base material in the direction of gravity. A method for producing a roll mold, wherein the aluminum substrate is taken out.   The at least one step of the steps (I) and (II) is characterized in that the aluminum base material is taken out from the liquid while rotating the aluminum base material around a central axis. The manufacturing method of the roll-shaped mold of description.   After at least one of the steps (I) and (II), the aluminum substrate is taken out from the liquid in a state where the central axis of the aluminum substrate is inclined with respect to the horizontal direction. The manufacturing method of the roll-shaped mold of Claim 1 or 2.   The aluminum substrate is taken out from the liquid while spraying at least one of a liquid and a gas on the aluminum substrate after at least one of the steps (I) and (II). The manufacturing method of the roll-shaped mold as described in any one of thru | or 3. The roll according to any one of claims 1 to 4, wherein the steps (I) and (II) are performed in a single treatment tank containing a mixed liquid of two or more kinds of acids. Method for manufacturing a mold. The method for producing a roll mold according to any one of claims 1 to 5, wherein the steps (I) and (II) are repeated. A method for producing an article having a fine relief structure on its surface,
A plurality of pores of anodized alumina formed on the outer peripheral surface of the roll-shaped mold obtained by the production method according to any one of claims 1 to 6 are transferred to an object to be transferred by an imprint method. A method for producing an article, which obtains an article having a plurality of convex portions having inverted pores on the surface.