JP2013137446A - Mold for manufacturing antireflection film and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antireflection film excellent in shape followability, a mold for manufacturing the antireflection film, and a method of manufacturing the same.SOLUTION: In a mold for manufacturing an antireflection film, an average pitch of a protrusion part interval or recess part interval of a rugged shape on a mold surface is 40 nm or more and 250 nm or less, a standard deviation in an average pitch distribution is 10% or more and 40% or less of the average pitch, and a flat part area ratio on the mold surface is 0% or more and 50% or less.

Description

  The present invention relates to an imaging optical system such as a camera, a projection optical system such as a display device, an observation optical system such as an image display device, and the like, and a mold for manufacturing an antireflection film that can be suitably used in optical design, and a method for manufacturing the mold. About.

  In recent years, for the purpose of application to displays, solar cells, and optical elements, an antireflection film having a fine concavo-convex structure at a wavelength level on its surface has been developed in place of the conventional antireflection film due to interference. By forming a shape on the antireflection film so that the occupying volume of the concavo-convex structure increases as it goes from the air interface side to the base material side, for the incident light, the refractive index is as if from the refractive index 1 of air. The refractive index of the substrate gradually changes, and reflection occurring at the interface having different refractive indexes can be suppressed. The manufacture is generally more complicated than conventional antireflection films caused by interference, but has the advantage of better angular characteristics and lower reflectivity over a wide wavelength range than antireflection films caused by interference.

  As a method for producing a mold for producing an antireflection film having such a fine concavo-convex structure on the surface, a method of providing pores on the surface of an anodized alumina obtained by anodizing aluminum (Patent Document 1), A method of etching a substrate using a filled single particle film as an etching mask and fine particles as a mask is known (Patent Document 2). As a method for forming a fine relief structure on the material surface, a method using a pattern of a microphase separation structure of a block copolymer is known (Patent Document 3). In addition, a mold having a fine concavo-convex structure on its surface is filled with a curable resin composition or a thermoplastic resin in a molten state and cured, and then peeled off from the mold to produce an antireflection film having a fine concavo-convex structure. A method is known (Patent Document 4).

JP 2008-189914 A JP 2009-034630 A JP 2001-151834 A JP 2008-197216 A

  It is necessary to design the pitch and height of a mold for manufacturing an antireflection film having a fine concavo-convex structure arbitrarily according to the wavelength of light of interest. However, according to the mold manufacturing method described in Patent Document 1, only a mold having a concavo-convex structure pitch of 100 nm can be manufactured. On the other hand, in the mold manufacturing method described in Patent Document 2, it is possible to produce a mold with different pitches and heights, but because the irregularity structure obtained by transferring is highly regular, the interference color is low. For example, it becomes a problem in appearance in applications such as an antireflection film. In order for the antireflection film to exhibit antireflection performance due to the fine concavo-convex structure, the area of the flat portion on the surface of the antireflection film needs to be small. However, the fine concavo-convex structure of Patent Document 3 is not intended to exhibit antireflection performance, and the area of the flat portion other than the concavo-convex structure is large. Therefore, the fine concavo-convex structure described in Patent Document 3 is not appropriate as a mold for manufacturing an antireflection film, and Patent Document 3 does not teach or suggest a technique for reducing the area of the flat portion.

  By the way, with the recent refinement of the optical apparatus, the shape of the optical element used is also complicated. As the shape of the optical element becomes complicated, it is possible to follow an optical element having a complicated shape, specifically, an optical element having a curved cross section in two orthogonal axes such as a spherical shape. There is a need for an antireflective coating.

  However, when a film having an uneven structure described in Patent Document 4 is filled with an ultraviolet curable resin or a thermosetting resin and cured, and then a thin film of an antireflection film is produced by peeling from the mold, There was a problem that the film was torn and difficult to produce. In addition, there is a similar problem when an antireflection film having a concavo-convex structure is produced by filling a molten thermoplastic resin into a mold, cooling and curing, and then peeling the mold from the mold. Furthermore, if the entire system is thick, when the antireflection film is attached to a member having a curved cross section in two orthogonal axes such as a spherical shape, the antireflection film cannot follow the shape and the gap ( Air gap) occurs, and as a result, the antireflection effect may not be obtained.

  This invention is made | formed in view of this problem, Comprising: It aims at providing the antireflection film excellent in shape followability, its mold for manufacture, and its manufacturing method.

The present invention is as follows.
[1] The average pitch of the convex or concave portions of the concavo-convex shape on the mold surface is 40 nm or more and 250 nm or less, the standard deviation in the average pitch distribution is 10% or more and 40% or less of the average pitch, and The mold for producing an antireflection film, wherein the area ratio of the flat portion on the mold surface is 0% or more and 50% or less.
[2] The following steps:
(1) forming a mask layer on the substrate surface;
(2) forming a resist layer containing the block copolymer (a) containing the aromatic ring-containing polymer (poly1) and the poly (meth) acrylate (poly2) as a block component on the mask layer;
(3) annealing the resist layer in an air atmosphere to phase-separate the block copolymer (a) to form a self-organized pattern of a sea-island structure;
(4) a step of selectively removing a poly (meth) acrylate portion in the phase-separated resist layer by etching;
(5) A step of etching using the resist layer patterned with the remaining aromatic ring-containing polymer portion as a mask, and transferring the pattern of the patterned resist layer to the mask layer;
(6) etching the patterned mask layer to transfer the pattern of the patterned mask layer to the substrate surface; and (7) the patterned resist layer and the patterned mask layer. A step of treating the patterned substrate surface with a release agent after removing the substrate;
The method for producing a mold for producing an antireflection film according to [1], comprising:
[3] An aromatic ring-containing homopolymer (b) synthesized from a monomer constituting the poly1 and / or a poly (meth) acrylate homopolymer (c) synthesized from a monomer constituting the poly2 The method according to [2], further comprising:
[4] The method according to [2] or [3], wherein a mass ratio of the poly1 to the poly2 is 10:90 to 90:10.
[5] The method according to any one of [2] to [4], wherein the block copolymer (a) has a number average molecular weight of 50,000 to 5,000,000.
[6] The number average molecular weight Mn1 of the poly1 is from 30,000 to 1,000,000, and the number average molecular weight Mn2 of the poly2 is from 10,000 to 1,500,000, [2] to [5 ] The method as described in any one of.
[7] When the Mn1 is larger than the Mn2, the resist layer includes a homopolymer (b). When the Mn1 is smaller than the Mn2, the resist layer includes a homopolymer (c). 6].
[8] The mass ratio of the block copolymer (a) to the entire resist layer is 30% by mass or more and 90% by mass or less, and the total mass ratio of the homopolymer (b) and the homopolymer (c) is 10% by mass. % Or more and 70 mass% or less, The method as described in any one of [2]-[7].
[9] The method according to any one of [2] to [8], wherein the etching in the step (6) is performed by isotropic reactive ion etching using an etching gas containing Ar.
[10] The method according to any one of [2] to [9], wherein the poly1 is polystyrene and the poly2 is polymethyl methacrylate.
[11] The method according to [10], wherein the proportion of the polystyrene in the block copolymer is 10% by mass or more and 95% by mass or less.
[12] The method according to any one of [2] to [11], wherein the substrate is Si.
[13] The method according to any one of [2] to [12], wherein the mask layer is SiO ₂ .
[14] Made of a resin having a yield strain of 1% or more and a tensile elongation of 10% or more, produced using the mold for producing an antireflection film according to [1], and having a thickness average of 0 .Antireflection film of 2 μm to 4 μm.
[15] The antireflection film according to [14], wherein the resin is an amorphous fluororesin having a perfluoroalkyl ether ring structure.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the mold which can manufacture easily the antireflection film which was excellent in antireflection property and was excellent in shape followability. And since the antireflection film manufactured by the mold for manufacturing the antireflection film of the present invention is excellent in shape followability, there is a very large gap even when a member having a curved cross section in two orthogonal directions, for example, a lens is attached. Hard to occur.

It is the elements on larger scale of the antireflection film of the present invention. It is a partial expanded sectional view of the uneven structure layer used by this invention. It is a figure which shows the measurement point at the time of calculating the thickness average of the self-supporting film | membrane used by this invention. It is a schematic diagram explaining the position shift by an aberration. It is a partial expanded sectional view of the uneven structure layer used by this invention.

<Mold for manufacturing antireflection film>
In the mold for producing an antireflection film of the present invention, the average pitch of the convex or concave portions of the concave and convex shapes on the mold surface is 40 nm or more and 250 nm or less, and the standard deviation in the average pitch distribution is 10% of the average pitch. The flat area ratio on the mold surface is 0% or more and 50% or less.

  The mold for producing an antireflection film of the present invention has an average pitch of 40 nm or more and 250 nm or less. Furthermore, the standard deviation in the average pitch distribution on the mold surface is 10% or more and 40% or less of the average pitch. Here, the average pitch is an average value of the distance between adjacent convex portions or the distance between concave portions. Furthermore, the flat part area ratio of the mold surface is 0% or more and 50% or less. Here, the flat portion area ratio is the ratio of the area of the flat portion to the surface area of the mold. The flat portion is a portion other than the concave portion and the convex portion on the mold surface. The average pitch, the standard deviation in the average pitch distribution, and the flat area ratio can be calculated using image analysis software, for example, A image-kun (manufactured by Asahi Kasei Engineering Co., Ltd.).

  The average pitch is preferably equal to or less than the target optical wavelength because the antireflection effect is enhanced. Since wavelengths of 150 nm to 2000 nm are usually used for optical elements, it is preferable to set the average pitch to 250 nm or less in order to enhance the antireflection effect. More preferably, it is 150 nm or less, Most preferably, it is 100 nm or less. Moreover, it is preferable to set it as 40 nm or more from a viewpoint of being comparable as the wavelength used for an optical element. More preferably, it is 50 nm or more, More preferably, it is 70 nm or more, Most preferably, it is 75 nm or more.

  In addition, when the standard deviation in the average pitch distribution on the mold surface is 10% or more and 40% or less of the average pitch, the regularity of the concavo-convex structure on the surface of the antireflection film produced by transferring the mold surface is suppressed, and the interference color is reduced. It is preferable because it can be made difficult to occur. More preferably, it is 15% or more and 35% or less, and particularly preferably 20% or more and 30% or less.

Further, in order for the antireflection film to exhibit antireflection performance due to the fine concavo-convex structure, it is preferable that there are few flat portions on the surface of the antireflection film. Therefore, it is preferable that the flat area ratio is 0% or more and 50% or less. More preferably, it is 0% or more and 40% or less, and particularly preferably 0% or more and 30% or less. By setting the flat area ratio to 0% or more and 30% or less, sufficient antireflection performance can be exhibited. In addition, from the viewpoint of obtaining good optical characteristics, the antireflection film produced by transferring the mold surface has a height of convex portions or a depth of concave portions of the mold surface of 0.5 to 2.0 times the average pitch. In particular, 1.0 to 2.0 times is preferable. The height of the convex portion and the depth of the concave portion defined here refer to the difference in height between the concave bottom point and the convex vertex of the concave-convex structure on the mold surface.

  The material of the mold is preferably a material that can ensure sufficient flatness, such as glass, quartz, aluminum oxide, sapphire, silicon nitride, silicon carbide and other ceramic substrates, silicon, germanium, gallium arsenide, gallium phosphide, gallium nitrogen, etc. Examples thereof include semiconductor substrates, polyesters such as polyethylene terephthalate and polynaphthalene terephthalate, polyethylene, polypropylene, polyvinyl alcohol, ethylene vinyl alcohol copolymers, cyclic polyolefin, polyimide, polyamide, polystyrene, and other resin substrates, paper, and nonwoven fabric. In particular, it is preferable to use silicon because the flatness of the mold surface with high accuracy can be secured and the unevenness on the mold surface can be easily produced.

In consideration of the possibility that the mold may crack due to temperature unevenness during drying of the concavo-convex structure layer, which will be described later, the smaller the mold thermal expansion coefficient, the better. In particular, the linear expansion coefficient at 0 ° C. to 300 ° C. is preferably 50 × 10 ⁻⁷ m / ° C. or less. The uneven structure on the mold surface may be provided with a shape corresponding to the uneven structure of the uneven structure layer described above.

<Method for producing mold for producing antireflection film>
The manufacturing method of the mold for manufacturing an antireflection film of the present invention is a method having the following steps:
(1) forming a mask layer on the substrate surface;
(2) forming a resist layer containing the block copolymer (a) containing the aromatic ring-containing polymer (poly1) and the poly (meth) acrylate (poly2) as a block component on the mask layer;
(3) annealing the resist layer in an air atmosphere to phase-separate the block copolymer to form a self-organized pattern of a sea-island structure;
(4) a step of selectively removing a poly (meth) acrylate portion in the phase-separated resist layer by etching;
(5) A step of etching using the resist layer patterned by the remaining aromatic ring-containing polymer portion as a mask, and transferring the pattern of the patterned resist layer to the mask layer;
(6) etching the patterned mask layer and transferring the pattern of the patterned mask layer to the substrate surface;
(7) A step of treating the patterned substrate surface with a release agent after removing the patterned resist layer and the patterned mask layer.

Hereafter, each said process is demonstrated in detail.
[(1) Process]
First, a mask layer is formed on the surface of the base material that becomes the mold surface. As a method for forming the mask layer, it may be appropriately selected from various publicly known methods such as vapor deposition, sputtering, thermal oxidation, high-frequency plasma CVD, microplasma CVD, ECR, thermal CVD, and LPCVD. it can.

[(2) Process]
Next, a resist layer is formed on the mask layer. As a method for forming a resist layer on a mask layer, a method for applying a resist layer forming solution described in detail below by a spin coater, bar coater, blade coater, curtain coater, spray coater, ink jet method, screen printing machine And a method of printing with a gravure printing machine, an offset printing machine, etc., and a spin coating method is preferred from the viewpoint of film thickness uniformity.

  After the formation of the resist layer, the obtained coating film can be heat-dried or vacuum-dried by air drying, oven, hot plate or the like to volatilize the solvent. The film thickness after volatilization of the solvent is preferably 1 μm or less, more preferably 10 nm or more and 500 nm or less, and further preferably 30 nm or more and 300 nm or less from the viewpoint of controlling the average pitch. As a method for measuring the film thickness, it can be obtained by a contact method in which a film is scratched and a terminal is brought into contact with the surface to measure the step, or a non-contact method using ellipsometry. The method of heating the coating film together with the base material can be roughly classified into a method of directly transferring heat from the lower side of the base material like a hot plate and a method of convection of a high-temperature gas like an oven.

[(3) Process]
By heating the resist in an air atmosphere and phase-separating the block copolymer in the resist layer, a self-organized pattern of a sea-island structure composed of two polymer phases can be formed. The resin composition for pattern formation constituting the resist layer spontaneously undergoes phase separation between the aromatic ring-containing polymer phase and the poly (meth) acrylate phase to form a self-assembled pattern. Here, the self-organization pattern refers to a pattern formed by spontaneous organization. The step of annealing the resist layer is preferably 1 minute or more and 1 hour or less when heated on a hot plate at a temperature range of 130 ° C. or higher and 280 ° C. or lower. When heating in an oven, 1 hour or more and 100 hours or less are preferable. In the case where heat is transferred directly from the lower side of the base material like a hot plate, a self-organized pattern of sea-island structure can be obtained in a shorter time. Heating is preferably performed in an atmosphere of a mixture of oxygen and inert gas. By heating in a temperature range of 130 ° C. or higher and 280 ° C. or lower, fluidity of the fired product can be secured, thermal decomposition can be suppressed, and self- An organized pattern can be formed. In the present invention, the flat portion is preferably made small by controlling the pattern of the sea-island structure in this way.

[(4) Process]
The aromatic ring-containing polymer phase in the resist layer has higher etching resistance than the poly (meth) acrylate phase. Therefore, the poly (meth) acrylate phase can be selectively removed from the self-organized pattern of the sea-island structure formed in the resist layer by etching, for example, reactive ion etching. In addition, (4) process and (5) process can be performed simultaneously or continuously.

  The aromatic ring-containing polymer phase remaining after reactive ion etching serves as a mask for the mask layer in the next step (5). Therefore, it is preferable that the aromatic ring-containing polymer phase remaining after reactive ion etching is thicker. In order to increase the remaining film thickness of the aromatic ring-containing polymer phase, the etching selectivity by reactive ion etching (poly (meth) acrylate etching rate / aromatic ring-containing polymer etching rate) is preferably 1 or more. . Further, the etching selectivity is more preferably 2 or more, and 4 or more is more preferable because the remaining film thickness of the aromatic ring-containing polymer portion sufficient as a mask for the mask layer in the step (5) can be obtained.

  Reactive ion etching is performed by anisotropic etching in which the etching rate in the vertical direction is higher than the horizontal direction of the object. As an etching apparatus that can be used, a reactive ion etching apparatus, an ion beam etching apparatus, or the like that can perform anisotropic etching and can generate a bias electric field of about 20 W at the minimum is preferably used. Can do.

[(5) Process]
In the step (4), the mask layer is etched using the highly etch-resistant aromatic ring-containing polymer phase remaining after the etching as a mask, and the sea-island structure self-organized pattern can be transferred to the mask layer. The mask layer is provided under the resist layer, and is a layer to which the self-organized pattern of the sea-island structure remaining after etching in the step (4) is transferred. The mask layer becomes a mask for the substrate in the next step (6).

  Etching of the mask layer needs to be completed before the aromatic ring-containing polymer phase is etched away. For this reason, the etching selectivity (mask layer etching rate / aromatic ring-containing polymer etching rate) is preferably 0.1 or more, more preferably 2 or more. If the etching selectivity is 4 or more, it is more preferable because the self-organized pattern of the sea-island structure can be transferred to the mask layer even if the remaining film thickness of the aromatic ring-containing polymer phase remaining in the step (4) is thin.

[(6) Process]
(5) Using the mask layer to which the sea-island structure self-organized pattern is transferred in the process as a mask, the base material is etched, for example, reactive ion etching, to transfer the sea-island structure self-organized pattern to the surface of the base material. it can.

  The etching of the base material needs to be completed before the mask layer to which the sea-island structure self-organized pattern is transferred in step (5) is etched away. Therefore, the etching selectivity (base material etching rate / mask layer etching rate) is preferably 0.1 or more, and more preferably 2 or more. An etching selectivity of 4 or more is more preferable because an uneven structure with a high aspect ratio can be formed on the substrate surface.

[(7) Process]
Examples of the method for treating the substrate surface with a release agent include a method in which the release agent is applied by a spin coater, bar coater, blade coater, curtain coater, spray coater, or ink jet method.

[Base material]
Examples of the material of the base material used in the method of the present invention include a ceramic substrate such as glass, quartz, aluminum oxide, sapphire, silicon nitride, and silicon carbide, and a semiconductor substrate such as silicon, germanium, gallium arsenide, gallium phosphorus, and gallium nitrogen. Polyester such as polyethylene terephthalate and polynaphthalene terephthalate, polyethylene, polypropylene, polyvinyl alcohol, ethylene vinyl alcohol copolymer, resin substrate such as cyclic polyolefin, polyimide, polyamide and polystyrene, paper, nonwoven fabric and the like. Among these materials, silicon is preferable because the mold can be easily produced. The substrate surface becomes the mold surface through the steps of the method of the present invention.

[Mask layer]
Examples of the material of the mask layer used in the method of the present invention include an insulating film such as an oxide film, a nitride film, and an oxynitride film, or a conductive film such as doped polysilicon and metal.

  When silicon is selected as the base material, the mask layer is preferably silicon oxide that has a large etching selectivity with silicon, and a method of forming silicon oxide as a mask layer is a thermal oxidation method that provides a simple and good-quality film. preferable.

[Resist layer]
The resist layer used in the method of the present invention is a resin composition containing a block copolymer (a), an aromatic ring-containing homopolymer (b), and a poly (meth) acrylate homopolymer (c).

  The mass ratio of the block copolymer (a) to the whole resist layer is 10% by mass or more and 100% by mass or less, preferably 30% by mass or more and 90% by mass or less, more preferably 40% by mass or more and 80% by mass or less. It is as follows.

  The total mass ratio of the homopolymer (b) and the homopolymer (c) to the entire resin composition constituting the resist layer may be in the range of 0.0 mass% to 90 mass%, more preferably 0. It is 0.0 mass%-80 mass%, More preferably, it is 10 mass%-70 mass%.

[Resist layer-block copolymer (a)]
The block copolymer (a) is a block copolymer containing an aromatic ring-containing polymer (poly1) and poly (meth) acrylate (poly2) as block portions. The total ratio of the aromatic ring-containing polymer portion and the poly (meth) acrylate portion with respect to the entire block copolymer (a) includes 50 mol% or more and 100 mol% or less, and more preferably 60 mol% or more and 100 mol%. Or less, more preferably 70 mol% or more and 100 mol% or less.

  The mass ratio of the aromatic ring-containing polymer part (poly1) and the poly (meth) acrylate part (poly2) includes a range of 10:90 to 90:10, preferably 20:80 to 85:15. Preferably it is 30:70 to 80:20. This range can vary depending on the molecular weight of each part, the amount of homopolymer used, and the like. The proportion of the aromatic ring-containing polymer portion (poly1) in the block copolymer (a) is 10% by mass to 95% by mass, preferably 20% by mass to 90% by mass, and more preferably 30%. It is not less than 85% by mass.

  The aromatic ring-containing polymer (poly1), which is one of the essential components of the block constituting the block copolymer (a) used in the present invention, is a vinyl monomer having a heteroaromatic ring such as an aromatic ring or a pyridine ring as a side chain. Polymers or copolymers with these monomers and / or other monomers. Examples of the aromatic ring-containing polymer (poly 1) include polystyrene (hereinafter also referred to as PS), polymethyl styrene, polyethyl styrene, poly t-butyl styrene, polymethoxy styrene, poly N, N-dimethylamino styrene, polychlorostyrene. , Polybromostyrene, polytrifluoromethylstyrene, polytrimethylsilylstyrene, polydivinylbenzene, polycyanostyrene, poly α-methylstyrene, polyvinyl naphthalene, polyvinyl biphenyl, polyvinyl pyrene, polyvinyl phenanthrene, polyisopropenyl naphthalene, polyvinyl pyridine, etc. Can be mentioned. The aromatic ring-containing polymer (poly1) most preferably used here is polystyrene from the viewpoint of availability of raw material monomers and ease of synthesis.

  The poly (meth) acrylate (poly2), which is another essential component of the block constituting the block copolymer (a) used in the present invention, is at least one kind selected from the group consisting of the following acrylate monomers and methacrylate monomers. Polymers or copolymers with these monomers and / or other monomers. Examples of the group consisting of acrylate monomers and methacrylate monomers that can be used here include methyl methacrylate (hereinafter also referred to as MMA), ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, methacrylic acid. Isobutyl acid, t-butyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, acrylic acid t -Butyl, n-hexyl acrylate, cyclohexyl acrylate and the like.

  The poly (meth) acrylate (poly2) most preferably used here is a methyl methacrylate homopolymer polymethyl methacrylate (hereinafter also referred to as PMMA) from the viewpoint of availability of raw material monomers and ease of synthesis.

  The block copolymer (a) used in the present invention is a diblock or triblock in which one end or both ends of the aromatic ring-containing polymer (poly1) and one end or both ends of the poly (meth) acrylate (poly2) are bonded. Or more multi-block copolymers. Among these block copolymers, a diblock copolymer in which one ends of the aromatic ring-containing polymer (poly1) and poly (meth) acrylate (poly2) are bonded to each other is preferable from the viewpoint of ease of synthesis. More preferably, it is a diblock copolymer of polystyrene and polymethyl methacrylate.

  The block copolymer (a) contains blocks of other polymer components in a proportion not exceeding 50 mol% in addition to the aromatic ring-containing polymer portion (poly1) and the poly (meth) acrylate portion (poly2). You can also. Specific examples of other polymer components include polyethylene oxide, polypropylene oxide, polytetramethylene glycol, and the like.

  The block copolymer (a) can be synthesized by living anion polymerization, living radical polymerization, or coupling of polymers having reactive end groups. For example, in flipping anionic polymerization, an aromatic ring-containing polymer is first synthesized using an anionic species such as butyl lithium as an initiator. Next, a block copolymer of the aromatic ring-containing polymer and the poly (meth) acrylate can be synthesized by polymerizing the (meth) acrylate monomer using the terminal of the aromatic ring-containing polymer as an initiator. At this time, the molecular weight of the polymer obtained can be increased by lowering the amount of initiator added, and the molecular weight of the polymer can be controlled as designed by removing impurities in the system such as water and air. Moreover, when superposing | polymerizing a poly (meth) acrylate part (poly2), a side reaction can be suppressed by lowering | hanging the temperature of a system to 0 degrees C or less. In living radical polymerization, first, a halogen compound such as bromine is added to the double bond of the (meth) acrylate monomer, the terminal is halogenated, and a halogenated poly (meth) acrylate is synthesized using a copper complex as a catalyst. Next, the aromatic ring-containing polymer (poly1) and the poly (meth) acrylate (poly2) block copolymer (a) are synthesized by synthesizing the aromatic ring-containing polymer (poly1) using the terminal halogen of the halogenated poly (meth) acrylate. ) Is obtained.

  First, an aromatic ring-containing polymer (poly1) is synthesized by living anion polymerization, and the terminal is halogenated, and then a (meth) acrylate monomer is reacted in the presence of a copper catalyst to produce an aromatic ring-containing polymer (poly1) and poly (meta). ) A block copolymer (a) of acrylate (poly2) can also be synthesized. Coupling between polymers having reactive end groups is, for example, blocking by reacting an aromatic ring-containing polymer (poly1) having an amino group at the end with poly (meth) acrylate (poly2) having maleic anhydride at the end. This is a method for obtaining a copolymer (a).

  The number average molecular weight of the block copolymer (a) that can be used in the present invention is preferably 50,000 or more, and more preferably 100,000 or more, from the viewpoint of obtaining a sea-island structure having the average pitch of 40 nm to 250 nm. On the other hand, from the viewpoint of molecular weight controllability at the time of synthesis and viscosity suppression when used as a composition, 5 million or less is preferable, and 2 million or less is more preferable. The average pitch tends to increase as the number average molecular weight of the block copolymer increases.

  The number average molecular weight of the aromatic ring-containing polymer portion (poly1) is preferably 30,000 or more, and more preferably 50,000 or more, from the viewpoint of forming a self-organized pattern having a sea-island structure. On the other hand, from the viewpoint of ease of synthesis, 1 million or less is preferable, and 500,000 or less is more preferable.

  The number average molecular weight of the poly (meth) acrylate moiety (poly2) is preferably 10,000 or more, and more preferably 20,000 or more, from the viewpoint of forming a self-organized pattern having a sea-island structure. On the other hand, from the viewpoint of ease of synthesis, 1.5 million or less is preferable, and 1 million or less is more preferable.

  In one embodiment of the present invention, in the block polymer (a), when the molecular weight of the aromatic ring-containing polymer (poly1) is larger than that of the poly (meth) acrylate (poly2), the aromatic ring-containing homopolymer (b ) Is added to the resist composition. When the molecular weight of the aromatic ring-containing polymer (poly1) is smaller than that of the poly (meth) acrylate (poly2), the poly (meth) acrylate homopolymer (c) is added to the resist composition. For example, the block polymer (a) is present in an amount of 30 to 100% by mass based on the entire resist composition, the molecular weight of poly1 is 30,000 to 600,000, and the molecular weight of poly2 is 10,000 to 100,000. In the block polymer (a), when the molecular weight of the aromatic ring-containing polymer (poly1) is larger than that of the poly (meth) acrylate (poly2), the homopolymer (b) is added to the entire resist composition. 0.0-70 mass% can be added. More preferably, the block polymer (a) is present in an amount of 40 to 100% by mass with respect to the entire resist composition, the molecular weight of poly1 is 50,000 to 500,000, and the molecular weight of poly2 is 20,000 to 9. When the molecular weight of the aromatic ring-containing polymer (poly1) in the block polymer (a) is larger than that of the poly (meth) acrylate (poly2) in the block polymer (a), the homopolymer (b) is used as a resist composition. 0.0-60 mass% can be added with respect to the whole thing.

  When the block polymer (a) is present in an amount of 20 to 60% by mass based on the entire resist composition, the molecular weight of poly1 is 200,000 to 600,000, and the molecular weight of poly2 is 600,000 to 1,000,000, a homopolymer ( c) can be added in an amount of 40 to 80% by mass based on the entire resist composition. More preferably, when the block polymer (a) is present in an amount of 30 to 50% by mass relative to the entire resist composition, the molecular weight of poly1 is 300,000 to 500,000, and the molecular weight of poly2 is 700,000 to 900,000 The homopolymer (c) can be added in an amount of 50 to 70% by mass based on the entire resist composition. By adjusting the molecular weight and addition amount of these constituent components, a desired sea-island structure can be formed, and a mold with few flat portions can be obtained.

  The number average molecular weight (hereinafter also referred to as Mn) of the block copolymer (a) is determined by the following method. First, measurement is performed by the following 1) measurement method of the number average molecular weight of the aromatic ring-containing polymer portion (poly1), and then measurement is performed by the following 2) measurement method of the number average molecular weight of the poly (meth) acrylate portion (poly2). I do. And when a block copolymer (a) consists only of an aromatic ring containing polymer part and a poly (meth) acrylate part (poly2), the number average molecular weight is the above aromatic ring containing polymer part (poly1) and poly (meth). This is the sum of the number average molecular weight of the acrylate moiety (poly2).

  When the block copolymer (a) contains other polymer parts other than the aromatic ring-containing polymer (poly1) and the poly (meth) acrylate (poly2), measurement of the number average molecular weight of 3) other polymer parts follows 2) Measure by method. The number average molecular weight is the sum of the number average molecular weights of the aromatic ring-containing polymer part (poly1), the poly (meth) acrylate part (poly2), and other polymer parts.

1) Method for measuring the number average molecular weight of the aromatic ring-containing polymer portion (poly1) When the block copolymer (a) is synthesized by living anionic polymerization, the aromatic ring-containing monomer (poly1) is first polymerized first, and then the acrylic monomer from the end Is polymerized. In this reaction process, when a part of the aromatic ring-containing monomer is polymerized and the reaction is stopped, only the aromatic ring-containing polymer portion (poly1) in the block copolymer can be obtained. Alternatively, the synthesized block copolymer is not dissolved in the block copolymer, but is subjected to Soxhlet extraction using a solvent that dissolves only the aromatic homopolymer (poly1), so that the aromatic ring-containing polymer portion (poly1) in the block copolymer is obtained. Can only get. In the case of PS-PMMA block copolymer, cyclohexane or the like serves as a solvent. The aromatic homopolymer thus extracted is first measured for the elution time distribution using gel permeation chromatography (hereinafter also referred to as GPC). Next, the elution time of several kinds of standard polystyrenes having different molecular weights is measured, and the elution time is converted into a molecular weight. From this result, the number Ni of molecules having a molecular weight Mi was determined, and the following formula:
Mn = Σ (MiNi) / ΣNi
From this, the number average molecular weight Mn can be determined.
Examples of the measuring apparatus and conditions are as follows.
Device: HLC-8020 manufactured by Tosoh Corporation
Eluent: Tetrahydrofuran 40 ° C
Column: Tosoh Corporation trade name TSK gel G5000HHR / G4000HHR / G3000HHR / G2500HHR Series flow rate: 1.0 ml / min
Reference material for molecular weight calibration: TSK standard polystyrene (12 samples) manufactured by Tosoh Corporation

2) Method for measuring number average molecular weight of poly (meth) acrylate moiety A block copolymer is dissolved in a deuterated solvent such as deuterated chloroform, and a 1H NMR spectrum is measured. At that time, by comparing the number of protons derived from the aromatic ring-containing polymer and the number of protons derived from the poly (meth) acrylate, the molar ratio of the aromatic ring-containing polymer portion and the poly (meth) acrylate portion in the block copolymer is determined. . Therefore, the number average molecular weight of the poly (meth) acrylate moiety can be determined from the number average molecular weight of the aromatic ring-containing polymer moiety previously determined by GPC.

3) Method for measuring number average molecular weight of other polymer portion A block copolymer is dissolved in a deuterated solvent such as deuterated chloroform, and a 1H NMR spectrum is measured. At that time, by comparing the number of protons derived from the aromatic ring-containing polymer and the number of protons derived from the other polymer part, the molar ratio of the aromatic ring-containing polymer part and the other polymer part in the block copolymer is determined. Therefore, the number average molecular weight of the other polymer portion can be determined from the number average molecular weight of the aromatic ring-containing polymer previously determined by GPC.

[Resist layer-aromatic ring-containing homopolymer (b)]
The aromatic ring-containing homopolymer (b) is an aromatic ring-containing homopolymer containing the monomer constituting the poly1.

  The weight average molecular weight (Mw) of the aromatic ring-containing homopolymer (b) is preferably 1,500 or more, and more preferably 2,000 or more, from the viewpoint of obtaining a sea-island structure with a clear outline of the island portion. On the other hand, from the viewpoint of obtaining a sea-island structure in which the shape of the island is close to a circle, it is preferably 8,000 or less, and more preferably 5,000 or less.

  Such an aromatic ring-containing homopolymer (b) can be synthesized by radical polymerization or anionic polymerization. In the case of radical polymerization, the amount of initiator, the amount of solvent, and the polymerization temperature are controlled. In the case of anionic polymerization, the amount of impurities in the system such as water and air in the system and the amount of initiator are controlled. The preferred range can be controlled.

The measuring method of the weight average molecular weight (Mw) of the aromatic ring-containing homopolymer (b) can be determined by the following method.
First, the elution time distribution of the aromatic ring-containing homopolymer (b) is measured using GPC. Next, the elution time of several kinds of standard polystyrenes having different molecular weights is measured, and the elution time is converted into a molecular weight. From this result, the number Ni of molecules having a molecular weight Mi was determined, and the following formula:
Mw = Σ (Mi ² Ni) / Σ (MiNi)
From this, the weight average molecular weight Mw can be determined.

[Resist layer-poly (meth) acrylate homopolymer (c)]
The poly (meth) acrylate homopolymer (c) is a poly (meth) acrylate homopolymer containing a monomer constituting the poly2. In the present specification, (meth) acrylate means acrylate and / or methacrylate.

  The weight average molecular weight of the poly (meth) acrylate homopolymer (c) is preferably 1,500 or more, and more preferably 2,000 or more, from the viewpoint of obtaining a sea-island structure with a clear outline of the island portion. On the other hand, from the viewpoint of suppressing phase separation from the poly (meth) acrylate portion in the block copolymer, 8,000 or less is preferable, and 5,000 or less is more preferable.

  Such a poly (meth) acrylate homopolymer (c) can be synthesized by radical polymerization or anionic polymerization, and particularly those having an aliphatic group at the terminal can be synthesized by using an aliphatic compound as a polymerization initiator. . In the case of radical polymerization, the amount of initiator, the amount of solvent, and the polymerization temperature are controlled. In the case of anionic polymerization, the amount of impurities in the system such as water and air in the system and the amount of initiator are controlled. The preferred range can be controlled.

The method for measuring the weight average molecular weight (Mw) of the poly (meth) acrylate homopolymer (c) can be determined by the following method.
First, the elution time distribution of the poly (meth) acrylate homopolymer (c) is measured using GPC. Next, the elution times of several types of standard polymethyl methacrylates having different molecular weights are measured, and the elution times are converted into molecular weights. From this result, the number Ni of molecules having a molecular weight Mi was determined, and the following formula:
Mw = Σ (Mi ² Ni) / Σ (MiNi)
From this, the weight average molecular weight Mw can be determined.

[Resist layer-resin composition]
The resin composition constituting the resist layer can be dissolved in a solvent to form a resist layer forming solution. Any solvent can be used as long as it can dissolve the resin composition constituting the resist layer. For example, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-ptyrolactone, Cyclopentanone, cyclohexanone, isophorone, N, N-dimethylacetamide, dimethylimidazolinone, tetramethylurea, dimethyl sulfoxide, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene Glycol monomethyl ether, propylene glycol monomethyl ether acetate (hereinafter also referred to as PGMEA), methyl lactate, milk Ethyl, butyl lactate, methyl-1,3-Petit Astragalus recall acetate, 1,3-Petit astragalus recall over 3 monomethyl ether, methyl 3-methoxypropionate. These can be used alone or in admixture of two or more. Specific preferred examples include N-methylpyrrolidone, cyclopentanone, cyclohexanone, γ-ptyrolactone, ethyl lactate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, and PGMEA. The mass ratio of the resin composition to the solution is preferably 1 to 30% by mass.

[Phase-separated resist layer]
The aromatic ring-containing polymer phase is mainly composed of poly1 and homopolymer (b) contained in the block copolymer (a). The poly (meth) acrylate phase is mainly composed of poly2 and homopolymer (c) contained in the block copolymer (a).

  When the total mass ratio of poly1 and homopolymer (b) to the entire resin composition constituting the resist layer is 10% by mass to 60% by mass, the aromatic ring-containing polymer phase is an island by phase separation by annealing. A self-organized pattern of sea-island structure in which the poly (meth) acrylate phase is the sea is formed.

  On the other hand, when the total mass ratio of poly1 and homopolymer (b) with respect to the entire resin composition constituting the resist layer is 60% by mass to 95% by mass, the aromatic ring-containing polymer phase is at sea by phase separation. A self-organized pattern of a sea-island structure in which the poly (meth) acrylate phase is an island is formed.

  Here, the sea-island structure is a structure in which a small amount of dispersed phase (islands) is scattered in a large amount of continuous phase (sea) when the phase separation structure formed by two types of polymers is viewed in plan. is there. Note that in this specification, the sea with the sea-island structure is also called a matrix, and the island is also called a dot.

  The aromatic ring-containing polymer portion has higher etching resistance than the poly (meth) acrylate portion. Therefore, when the aromatic ring-containing polymer phase is an island, a convex island-shaped self-organized pattern of the aromatic ring-containing polymer phase can be formed by selectively etching only the sea portion of the sea-island structure. . On the other hand, when the aromatic ring-containing polymer phase is the sea, a concave island-like self-organized pattern of the poly (meth) acrylate phase can be formed by selectively etching only the island portion of the sea-island structure. .

  Then, using the self-organized pattern of the aromatic ring-containing polymer phase as a mask, the mask layer can be etched to transfer the self-assembled pattern to the mask layer. Furthermore, using the pattern transferred to the mask layer as a mask, the substrate is etched, and the self-assembled pattern is transferred to the substrate surface, resulting in a sea-island structure based on the self-assembled pattern on the substrate surface. An uneven structure can be formed.

  In the present invention, by using a resist layer comprising a block copolymer containing an aromatic ring-containing polymer and poly (meth) acrylate as a block component, the average pitch is 40 nm or more and 250 nm or less, and the standard deviation in the average pitch distribution is A sea-island structure pattern having an average pitch of 10% to 40% can be obtained. Here, the average pitch is an average value of the distance between adjacent convex portions or the distance between concave portions. The standard deviation in the average pitch and the average pitch distribution can be calculated using image analysis software, for example, A image-kun (manufactured by Asahi Kasei Engineering Co., Ltd.).

[Etching gas for poly (meth) acrylate phase]
As an etching gas for selectively removing the poly (meth) acrylate phase from the self-organized pattern of the sea-island structure formed in the phase-separated resist layer, for example, Ar, SF ₆ , F ₂ , CF ₄ , _{C 4 F 8, C 5 F} 8, C 2 F 6, C 3 F 6, C 4 F 6, CHF 3, CH 2 F 2, CH 3 F, C 3 F 8, Cl 2, CCl 4, SiCl 4 , BCl ₂ , BCl ₃ , Br ₂ , Br ₃ , HBr, CBrF ₃ , HCl, CH ₄ , NH ₃ , O ₂ , H ₂ , N ₂ , CO, CO _{2 and the} like. One or more of these etching gases can be used. Among these etching gases, a gas having an etching selectivity of 4 or more, for example, CF ₄ is preferable.

[Mask layer]
Examples of the material used for the mask layer include an insulating film such as an oxide film, a nitride film, and an oxynitride film, or a conductive film such as doped polysilicon and metal. When silicon is selected as the base material, the mask layer is preferably silicon oxide that can take a large etching selection ratio with respect to silicon.

[Mask layer etching gas]
(4) As an etching gas for transferring the self-organized pattern of the sea-island structure remaining after the process to the mask layer, for example, Ar, SF ₆ , F ₂ , CF ₄ , C ₄ F ₈ , C ₅ F ₈ , C ₂ F ₆ , C ₃ F ₆ , C ₄ F ₆ , CHF ₃ , CH ₂ F ₂ , CH ₃ F, C ₃ F ₈ , Cl ₂ , CCl ₄ , SiCl ₄ , BCl ₂ , BCl ₃ , Br ₂ , Br ₃ , HBr, CBrF ₃ , HCl, CH ₄ , NH ₃ , O ₂ , H ₂ , N ₂ , CO, CO _{2 and the} like. One or more of these etching gases can be used. Among these etching gases, when silicon oxide is selected as the mask layer, a gas having an etching selectivity (silicon oxide etching rate / aromatic ring-containing polymer etching rate) of 4 or more, for example, CF ₄ is preferable.

[Substrate etching gas]
(5) Etching gas used for reactive ion etching for transferring the self-organized pattern of the sea-island structure transferred onto the mask layer through the process to the substrate is, for example, Ar, SF ₆ , F ₂ , CF ₄ , C ₄ F ₈ , C ₅ F ₈ , C ₂ F ₆ , C ₃ F ₆ , C ₄ F ₆ , CHF ₃ , CH ₂ F ₂ , CH ₃ F, C ₃ F ₈ , Cl ₂ , CCl ₄ , SiCl ₄ , BCl ₂ , BCl ₃ , Br ₂ , Br ₃ , HBr, CBrF ₃ , HCl, CH ₄ , NH ₃ , O ₂ , H ₂ , N ₂ , CO, CO _2, etc. One or more of them can be used. When silicon is selected as the substrate and silicon oxide is selected as the mask layer, a gas having an etching selectivity (silicon etching rate / silicon oxide etching rate) of 4 or more, for example, Cl ₂ is preferable. Further, from the viewpoint of setting the flat area ratio on the mold surface manufactured through all the steps to 0% or more and 50% or less, the reactive ion etching in the step (6) is performed in all directions with respect to the object. It is preferable to perform isotropic reactive ion etching with a uniform etching rate. When isotropic reactive etching is performed when Cl ₂ is used as an etching gas, it is preferable to add Ar to the etching gas.

[Release agent]
The mold release property can be improved with the mold release agent on the surface of the base material on which the self-organized pattern of the sea-island structure is formed. As a mold release agent, for example, OPTOOL DSX, Durasurf HD-1100, HD-2100 (manufactured by Daikin Industries), Novec EGC1720 (manufactured by Sumitomo 3M), Cytop Grade M (manufactured by AGC), OPC -800 (made by N material) etc. are mentioned.

<Antireflection film>
The antireflection film produced by the mold of the present invention has a concavo-convex structure layer formed by transferring from the concavo-convex structure on the mold surface on the surface of the antireflection film. Further, the average pitch in the concavo-convex structure formed by transferring from the mold on the surface of the antireflection film is 40 nm or more and 250 nm or less, and the standard deviation in the average pitch distribution is 10% or more and 40% or less of the average pitch. The flat portion area ratio in the structure is 0% or more and 50% or less. In one embodiment, the average thickness of the antireflection film is 0.2 μm or more and 4 μm or less, the yield strain of the concavo-convex structure layer is 1% or more, and the tensile elongation is 10% or more. And

  When the antireflection film is manufactured by transferring the structure of the mold surface, the concave portion of the mold becomes a convex portion in the antireflection film, and the convex portion of the mold becomes a concave portion in the antireflection film. In addition, when an antireflection film is manufactured by transferring a structure derived from the self-organized pattern of the sea-island structure on the mold surface, when the island of the mold is concave, the island is convex in the antireflection film. When the island is convex, the island is concave in the antireflection film.

  Since the antireflection film produced by the mold of the present invention can exhibit an antireflection function by a fine concavo-convex structure, the average thickness thereof is 0.2 μm to 4 μm, which is a conventional high refractive index material and low refractive index material. It is much thinner than the antireflection film which is an alternating laminate of the above. Moreover, since it is formed using the raw material which has a specific characteristic, it is excellent in shape followability. Further, a gap is extremely unlikely to occur even when affixed to a member having a curved cross section in two orthogonal axes such as a spherical shape. The thinner the average thickness of the antireflection film, the better the shape followability. However, the average thickness of the antireflection film is preferably 0.5 μm to 2 μm because of the strength of the antireflection film and the ease of forming a uniform film. Preferably it is 0.7 micrometer-1.5 micrometers. In addition, it is preferable also from a viewpoint of reducing the position shift by an aberration that an average thickness shall be 4 micrometers or less. The positional deviation due to aberration here is caused by the fact that the refractive index of a substance differs depending on the wavelength of light.

  The shape of the island in the concavo-convex structure is not particularly limited. However, when the island has a convex shape, a shape that continuously changes in the height direction of the island is preferable because the antireflection effect is enhanced. Further, when the island has a concave shape, a shape that continuously changes in the depth direction of the island is preferable because the antireflection effect is enhanced. As a preferable island shape, for example, a shape in which the cross-sectional shape in the thickness direction is a trapezoidal shape, a rectangular shape, a rectangular shape, a prism shape, a triangular shape, or a semicircular shape can be considered. And, as a preferable uneven structure, for example, a cross-sectional shape in the thickness direction is trapezoidal, rectangular, square, prismatic or triangular, a shape in which convex or concave portions that are semicircular are continuously arranged, a sinusoidal shape, etc. Such a periodic uneven structure is conceivable. Here, the sinusoidal shape means that it has a curved portion formed by repetition of a concave portion and a convex portion. In addition, the curved part should just be a curved curve, for example, the shape with a constriction in a convex part is also included in a sine wave form. Among these cross-sectional shapes, a triangular or sine wave shape provides a high antireflection effect.

  Furthermore, if the cross-sectional shape of the convex part is a shape that continuously changes in the height direction such as a trapezoid, a rectangle, a square, a prism, a triangle, and a semicircle in two orthogonal directions, the incident direction of light The difference in the antireflection effect due to is reduced, which is preferable. As a preferable shape of the convex portion, for example, a polygonal pyramid shape such as a triangular pyramid, a quadrangular pyramid, a hexagonal pyramid, a conical shape, a truncated polygonal pyramid shape, a truncated conical shape, or the like can be considered. Here, the truncated polygonal pyramid refers to a shape obtained by horizontally cutting the top of the polygonal pyramid, and the truncated cone refers to a shape obtained by horizontally cutting the top of the cone. In these polygonal pyramid shape, conical shape, truncated polygonal pyramid shape, and truncated cone shape, a portion where each surface contacts may be a curved surface, and a connecting portion between adjacent convex shapes may be a curved surface.

  Further, it is preferable that the average pitch in the concavo-convex structure formed by transferring from the mold is equal to or less than the use wavelength, since the antireflection effect is enhanced. Since wavelengths of 150 nm to 2000 nm are usually used for optical elements, it is preferable that the average pitch in the concavo-convex structure formed by transferring from the mold is 250 nm or less in order to enhance the antireflection effect. More preferably, it is 150 nm or less, Most preferably, it is 100 nm or less. Moreover, it is preferable to set it as 40 nm or more from a viewpoint of being comparable as the wavelength used for an optical element. More preferably, it is 50 nm or more, Especially preferably, it is 70 nm or more.

  In addition, by making the standard deviation in the average pitch distribution formed by transferring from the mold 10% or more and 40% or less of the average pitch, the regularity of the concavo-convex structure on the surface of the antireflection film produced by transferring the mold surface can be improved. This is preferable because it is possible to suppress the interference color and prevent the interference color from being generated. More preferably, it is 15% or more and 35% or less, and particularly preferably 20% or more and 30% or less.

  Further, in order for the antireflection film to exhibit antireflection performance due to the fine concavo-convex structure, it is preferable that there are few flat portions on the surface of the antireflection film. Therefore, the flat area ratio in the self-organized pattern of the sea-island structure formed by transferring from the mold is preferably 0% or more and 50% or less. More preferably, it is 0% or more and 40% or less, and particularly preferably 0% or more and 30% or more. By setting the flat area ratio to 0% or more and 30% or less, sufficient antireflection performance can be exhibited.

  The height of the convex portion or the depth of the concave portion is 0.5 to 2.0 times, particularly 1.0 to 2.0 times the average pitch in the concavo-convex structure formed by transferring from the mold. When it exists, a favorable optical characteristic can be acquired and it is preferable. The height of the convex portion and the depth of the concave portion defined here refer to the difference in height between the concave bottom point and the convex vertex of the concave-convex structure formed by transferring from the mold.

  When the shape of the convex portion is a pyramid shape or a conical shape, it is preferable that the height of the convex portion is 0.3 times or more of the operating wavelength because a high antireflection effect can be obtained. Also, when the convex shape is a quadrangular pyramid shape, the height is 0.5 times or more of the working wavelength, and when it is a cone shape, the height is 0.45 times or more of the working wavelength, and the cones overlap in the horizontal direction. In this case, it is preferable that the ratio is 0.65 times or more because a particularly high antireflection effect can be obtained. The height of the convex portion is preferably as high as possible, but a sufficient antireflection effect can be obtained even at 1 μm or less.

  The concavo-convex structure may be provided on both sides of the antireflection film and the concavo-convex structure layer, not only on one side. When provided on both sides, the antireflection effect can be enhanced more than when the concavo-convex structure is provided only on one side, and therefore it is preferable to provide the concavo-convex structure on both sides. Moreover, when a concavo-convex structure is provided on the surface side in contact with the pressure-sensitive adhesive layer and the adhesive layer described later, the adhesion with the pressure-sensitive adhesive layer and the adhesive layer is improved by the anchor effect, which is preferable.

  An antireflection structure can be formed from the antireflection film and a peelable body that can be peeled off from the antireflection film provided on the back surface of the antireflection film. In this case, the concavo-convex structure layer and the peeled body are preferably in contact with each other. Such an antireflection structure is suitable from the viewpoint of easily handling the antireflection film before use. In addition, it is preferable that the surface of the peeled body facing the concavo-convex structure layer has a substantially spherical shape because the peeled body can be easily peeled off.

  Moreover, it is possible to form an antireflection structure from an antireflection film and an adhesive layer or an adhesive layer provided on the back surface of the antireflection film. In this case, it is preferable that the concavo-convex structure layer is in contact with the pressure-sensitive adhesive layer or the adhesive layer. Such an antireflection structure is suitable from the viewpoint of easily handling the antireflection film before use.

[Antireflection film-production method]
Hereinafter, a method for producing the antireflection film will be described.
A method for producing the antireflection film is not particularly limited. For example, a resin composition having a yield strain of 1% or more and a tensile elongation of 10% or more is dissolved in an organic solvent. A polymer solution is prepared. An example is a method in which the prepared polymer solution is applied to a mold surface having a concavo-convex structure on the surface, and then dried and peeled to obtain an antireflection film having a thickness average of 0.2 μm or more and 4 μm or less.

  The uneven structure layer can be produced by the following three steps. (1) A polymer solution is prepared by dissolving a resin composition having a yield strain of 1% or more and a tensile elongation of 10% or more in an organic solvent. (2) A polymer solution is applied to a mold having a concavo-convex structure on the surface so as to have a predetermined film thickness. (3) The applied polymer solution is dried and peeled off from the mold.

  Examples of the method for applying the polymer solution to the mold include a spin coating method, a roll coating method, a knife coating method, and a casting method. From the viewpoint of film thickness uniformity, foreign matter management, and thinning, A coating method is particularly preferred. Hereinafter, the film forming method by the spin coat method will be described.

  The concavo-convex structure layer is produced using a polymer solution in which the above-described film material is dissolved in an organic solvent. As the solvent, those which have very little volatilization at ambient temperature and whose boiling point is not too high are preferable. In view of the above, the solvent preferably has a boiling point of 100 to 200 ° C. Examples of such a solvent include aliphatic hydrocarbon compounds, aromatic compounds, halogenated hydrocarbons such as chlorinated hydrocarbons, ester compounds, and ketone compounds. Among them, saturated aliphatic hydrocarbon compounds such as alicyclic hydrocarbons, aromatic solvents, halogenated hydrocarbons and other organic solvents can be preferably used for cycloolefin resins, and chlorine derivatives are used for cellulose derivatives. Soluble in single or mixed organic solvents such as hydrocarbons, ketones, esters, alkoxy alcohols, benzene, alcohols. Examples of these organic solvents include organic solvents such as chlorinated hydrocarbons, ester compounds, and ketone compounds. As the chlorinated hydrocarbon, methylene chloride, ethylene chloride, propylene chloride and the like are preferably used, and as the ketone compound organic solvent, acetone, methyl ethyl ketone, methyl isobutyl ketone and the like are preferably used. As the ester compound organic solvent, acetate esters (methyl acetate, ethyl acetate, butyl acetate, etc.) and lactate esters (ethyl lactate, butyl lactate, etc.) are preferably used. In addition, benzene, ethanol, methanol, cellosolve acetate, carbitol and the like can be used as a single or mixed solvent. When the concentration of the polymer solution is 1 to 10% by mass, the thickness variation of the concavo-convex structure layer during drying is preferably reduced. More preferably, it is 3-8 mass%. In order to increase the light transmittance in the concavo-convex structure layer and to reduce foreign matter in the concavo-convex structure layer, the polymer solution preferably has an absorbance of 0.05 or less.

  The thickness and uniformity (thickness variation) of the concavo-convex structure layer are mainly determined by the liquid temperature of the polymer solution, the ambient temperature / humidity, and the number of rotations of the film formation substrate. From the viewpoint of thinning and uniformity, the liquid temperature of the polymer solution is preferably about the same as the ambient temperature (10 to 30 ° C.), and the temperature of the mold is also preferably about the same as the ambient temperature. It is preferable that the liquid temperature, the ambient temperature, and the temperature of the mold be approximately the same, because thickness variation can be suppressed. The humidity is preferably 30 to 60%. After a suitable amount of the polymer solution is dropped on the film formation substrate, the film formation substrate is rotated at a rotational speed of 50 to 5000 revolutions per minute to form a film. From the viewpoint of film uniformity, the number of revolutions is preferably 50 to 500 revolutions per minute, more preferably 75 to 400 revolutions per minute, and still more preferably 100 to 300 revolutions per minute. The rotation time is preferably 30 seconds or longer and 120 seconds or shorter, and more preferably 30 seconds or longer and 60 seconds or shorter.

  The thickness of the concavo-convex structure layer is preferably about 0.2 μm to 4 μm, and is preferably 0.5 μm to 2 μm from the strength of the concavo-convex structure layer and the ease of forming a uniform film. Especially preferably, it is 0.7 micrometer-1.5 micrometers.

  After film formation, the mold is placed on a heated hot plate and dried to volatilize the solvent. From the viewpoint of film uniformity, drying is preferably performed in two stages of low temperature drying and high temperature drying. After drying at 70 ° C. to 90 ° C. for about 4 minutes to 6 minutes, 160 ° C. to 200 ° C. for 4 minutes to It is preferable to dry for about 6 minutes.

  After the film is dried, the film is peeled off from the mold. When the concavo-convex structure layer is peeled from the mold, the releasability is important. In order to facilitate film formation by spin coating and facilitate separation after film formation, it is necessary to optimize the contact angle between the film material of the concavo-convex structure layer and the substrate. Silane coupling is known as a method for controlling the contact angle of a substrate. In order to couple a substrate made of an inorganic material, a silane having an ether bond at the terminal is brought into contact with the substrate surface and reacted. Further, the other end group is a group having low affinity with the membrane material, so that the releasability is improved. Fluorine is highly effective as a mold release agent, and in order to achieve high mold release properties, the other terminal group is particularly preferably a fluorine terminal.

  Since stress is applied to the film at the time of peeling from the mold, the yield strain of the rugged structure layer can be used to peel the film from the mold while suppressing film breakage of the thin rugged structure layer having a thickness of 0.2 μm to 4 μm. Must be 1% or more and the tensile elongation should be 10% or more. Therefore, it is necessary to use a resin composition having a yield strain of 1% or more and a tensile elongation of 10% or more. The larger the yield strain and the tensile elongation, the less likely the film tearing occurs when the film is peeled off from the mold, and it is possible to produce a concavo-convex structure layer and an antireflection film with a larger area. The yield strain is more preferably 2% or more, further preferably 4% or more, and particularly preferably 5% or more. The tensile elongation is more preferably 50% or more, still more preferably 100% or more, and particularly preferably 160% or more. The upper limits of the yield strain and the tensile elongation are not particularly limited. However, if the yield strain is 1% to 30% and the tensile elongation is 10% to 500%, film breakage can be sufficiently suppressed.

  In addition, when the produced concavo-convex structure layer has a yield strain of 1% or more and a tensile elongation of 10% or more, it can be stretched while being pulled with respect to the member. . The yield strain is more preferably 2% or more, further preferably 4% or more, and particularly preferably 5% or more. The tensile elongation is more preferably 50% or more, still more preferably 100% or more, and particularly preferably 160% or more. There is no upper limit on the yield strain and tensile elongation, but sufficient shape followability can be obtained if the yield strain is 1% to 30% and the tensile elongation is 10% to 500%.

[Antireflection film-material]
Antireflection films are often designed with the antireflection effect on visible light and ultraviolet light in mind. Therefore, it is preferable that the resin contained in the resin composition has a high light transmittance in the visible light region and the ultraviolet region. Specific examples of such resins include polymethyl methacrylate resin, polycarbonate resin, polystyrene resin, cross-linked polyethylene resin, polyvinyl chloride resin, polyarylate resin, polyphenylene ether resin, modified polyphenylene ether resin, polyetherimide resin, poly Ether sulfone resin, polysulfone resin, polyether ketone resin, cellulose derivative (nitrocellulose, cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate, etc., or a mixture of two or more thereof), cycloolefin resin (norbornene heavy For example, Apel (registered trademark) (manufactured by Mitsui Chemicals), Topas (registered trademark) (manufactured by Polyplastics Co., Ltd.), Zeo (Registered trademark) or ZEONOR (registered trademark) (manufactured by ZEON Co., Ltd.), Arton (registered trademark) (manufactured by JSR), etc.), fluorinated resin (tetrafluoroethylene-vinylidene fluoride-hexafluoropropylene terpolymer) ) Teflon AF (registered trademark) manufactured by Du Pont, a fluororesin having a perfluoroalkyl ether ring structure, Cytop (trade name) manufactured by Asahi Glass Co., and Algoflon (trade name) manufactured by Augmont Amorphous thermoplastic resins such as polyethylene terephthalate resin (PET), polyethylene naphthalate resin, polyethylene resin, polypropylene resin, polybutylene terephthalate resin, aromatic polyester resin, polyacetal resin, polyamide resin, etc. Can be considered.

  Among the above resins, a resin having a yield strain of 1% or more and a tensile elongation of 10% or more is preferably used as the main component of the resin composition. The main component means 50% by weight or more.

  Among resins having a yield strain of 1% or more and a tensile elongation of 10% or more, fluorine resins or cycloolefin resins having a perfluoroalkyl ether ring structure, cellulose derivatives (especially cellulose acetate propionate). (Preferably) has good releasability from a film-forming substrate having a concavo-convex structure, which will be described later, and is excellent in stretchability, so that a thinner concavo-convex structure layer can be produced. In particular, a fluororesin having a perfluoroalkyl ether ring structure is preferable. The amount of the resin component having a yield strain of 1% or more and a tensile elongation of 10% or more contained in the resin composition is preferably 80% or more, more preferably 90% or more, and particularly preferably 95%. That's it. Moreover, you may mix | blend the antioxidant for improving the effect of a ultraviolet absorber, a light stabilizer, a light stabilizer, etc. with a resin composition according to the intended purpose.

[Antireflection film-usage]
Since the antireflection film of the present invention does not require a base material layer that supports the concavo-convex structure layer due to its production method, it is possible to directly provide an adhesive layer or an adhesive layer on the back surface of the concavo-convex structure layer. And it becomes an extremely thin antireflection structure by providing a pressure-sensitive adhesive layer or an adhesive layer directly on the back of the concavo-convex structure layer. As the pressure-sensitive adhesive and adhesive, it is preferable to use a pressure-sensitive adhesive and adhesive that are suitably used for optical material applications. Specific examples of the adhesive include urethane adhesives and acrylic adhesives, and specific examples of the adhesive include acrylic adhesives, urethane adhesives, epoxy adhesives, and UV curable adhesives. An agent or the like is preferable. The thickness of the pressure-sensitive adhesive and adhesive is preferably as thin as possible so that practical pressure-sensitive adhesion and adhesive strength can be maintained, and deformation of the adherend can be suppressed. It is also possible to provide a peelable body that can be peeled directly from the concavo-convex structure layer on the back surface of the concavo-convex structure layer without providing a pressure-sensitive adhesive layer or an adhesive layer on the back surface of the concavo-convex structure layer. There is no restriction | limiting in particular in a peeling body, For example, a glass substrate, a film base material, an optical element etc. can be considered. The peeled body may have a spherical shape as well as a planar shape.

  The antireflection film is usually in a state where a peelable body that can be peeled off from the antireflection film is provided on the back surface of the antireflection film, or an adhesive material layer is provided on the back surface of the antireflection film, and further the antireflection of the adhesive layer It is stored in a state where a peelable body that can be peeled off from the pressure-sensitive adhesive layer is provided on the surface opposite to the surface having the film, and is peeled off from the peelable body during use.

  The antireflection film of the present invention has a very thin average thickness of 0.2 to 4 μm and low rigidity. Therefore, the storage method includes an antireflection film and a peelable body that can be peeled off from the antireflection film provided on the back surface of the antireflection film and that has a curved cross section in two orthogonal directions. A method of storing the antireflection film as a laminate is preferred. It can also be peeled off from the anti-reflection film, the adhesive layer provided on the back surface of the anti-reflection film, and the adhesive layer provided on the opposite side of the adhesive layer having the anti-reflection film. And the method of storing as a laminated body containing the peeling body in which a cross section becomes a curved-surface shape in the biaxial directions orthogonal to each other is preferable. When the peeled body has a curved surface in the two biaxial directions perpendicular to each other, the antireflective film is removed from the peeled body compared to a peeled body having a planar shape or a curved shape in the cross section only in one axial direction (for example, a roll shape). Or it becomes easy to peel off from a corner | angular part when peeling an antireflection film with an adhesive material layer, and handleability improves markedly.

  Moreover, the form which directly peels with respect to an anti-reflective film on the back surface of a concavo-convex structure layer, and provides the peeling body in which a cross section becomes a curved-surface shape in the orthogonal biaxial direction is preferable. In addition, an adhesive material layer is directly provided on the back surface of the uneven structure layer, and the adhesive material layer can be peeled from the adhesive material layer on the surface opposite to the surface having the uneven structure layer, and is cross-sectioned in two orthogonal axes. Is a form provided with a peeled body having a curved shape, since the antireflective film after peeling from the peeled body is thin and an antireflective film having excellent shape followability is preferred.

  Since the antireflection film produced by the mold of the present invention is excellent in shape followability, image display devices such as touch panels, liquid crystal display panels, plasma displays, and organic EL displays, projection optical systems such as projectors, and observation optical systems such as optical lenses It can be suitably used for optical elements such as an imaging optical system such as a camera, a polarizing beam splitter, a light emitting diode tip of a light emitting diode, a surface of a solar cell panel, and the like.

  FIG. 1 is a partially enlarged cross-sectional view of an example of an antireflection film according to this embodiment. In FIG. 1, the antireflection film 4 includes a concavo-convex structure layer 1 in which a concavo-convex structure 5 formed by transferring a concavo-convex structure derived from the self-organized pattern of the sea-island structure on the mold surface is formed on one surface. The thin film layer 2 is provided on the other surface of the uneven structure layer 1.

  Here, the concavo-convex structure layer 1 has a concavo-convex structure 5 formed by transferring a concavo-convex structure derived from the self-organized pattern of the sea-island structure on the mold surface to the surface, and is integrated with the concavo-convex structure 5. Refers to the layer being formed.

  In addition, when the concavo-convex structure 5 formed by transferring from the mold is provided on one surface of the concavo-convex structure layer 1, and the concavo-convex structure formed by transferring from the mold is not provided on the other surface, The surface on which the concave-convex structure formed by transferring from the mold is not provided is defined as the back surface. On the other hand, when the concavo-convex structure formed by transferring from the mold is provided on both surfaces of the concavo-convex structure layer, the surface having the larger average pitch in the concavo-convex structure formed by transferring from the mold is defined as the back surface. Moreover, when the said average pitch in the uneven structure formed by transcribe | transferring from a mold is the same, let arbitrary one side be a back surface.

  A coating layer 3 may be provided on the surface of the uneven structure 5. Examples of coating layers include hard coat layers, metal thin film layers, other antireflection layers, moisture proof layers, antistatic layers, electromagnetic wave shielding layers, near infrared absorption layers, ultraviolet absorption layers, and selective absorption filter layers. Any number of layers may be stacked.

  As the above-mentioned hard coat layer, a known acrylic polymer, urethane polymer, epoxy polymer, silicone polymer, silica compound, silicon (Si) oxide, which is a curable resin that is cured by active energy rays, Examples thereof include nitrides, halides, carbide simple substances or composites thereof, and metal thin film layers. As the metal thin film layer, aluminum (Al), chromium (Cr), yttrium (Y), zirconia (Zr), tantalum (Ta), titanium (Ti), barium (Ba), indium (In), tin (Sn), Zinc (Zn), Magnesium (Mg), Calcium (Ca), Cerium (Ce), Copper (Cu), Silver (Ag), Gold (Au) and other metal oxides, nitrides, halides and carbides Or those composites are mentioned. Other antireflection layers include tetrafluoroethylene-vinylidene fluoride-hexafluoropropylene terpolymers and fluororesins having a perfluoroalkyl ether ring structure (particularly, Teflon AF (registered by Du Pont)). Trademark), Cytop (trade name) manufactured by Asahi Glass Co., Ltd., Algoflon (trade name) manufactured by Augmont, and polyfluoroacrylate are preferred.), Calcium fluoride, magnesium fluoride, barium fluoride, etc. Examples thereof include an antireflection layer formed from a low material.

  In order to suppress damage to the optical member, the outermost surface layer of the coating layer 3 forming the antireflection film surface 7 is preferably a resin layer, and particularly durometer hardness (measured in accordance with JIS K7215). Is desirably a resin layer of HDA30 or more and HDD90 or less. Further, from the viewpoint of followability to a member having a spherical shape, the coating layer 3 is desirably a resin layer over the entire layer, and in particular, the durometer hardness (measured in accordance with JIS K7215 over the entire layer). ) Is preferably a resin layer of HDA30 or more and HDD90 or less. It is preferable that the coating layer 3 has a refractive index as close as possible to the uneven structure 5 of the uneven structure layer 1 because the antireflection effect is enhanced. As is clear from the definition of the uneven structure layer 1, the coating layer 3 is not included in the uneven structure layer 1.

  Further, the thin film layer 2 may be laminated on the back surface of the uneven structure layer 1. As the thin film layer 2, it is preferable to use the above-mentioned other antireflection layers, metal thin film layers, and the like. The thin film layer 2 may be a single layer or multiple layers. As is clear from the definition of the uneven structure layer 1, the thin film layer 2 on the back surface is not included in the uneven structure layer 1.

  FIG. 4 is a schematic diagram for explaining misalignment due to aberration. Since the refraction angle at the interface when entering the antireflection film from an oblique direction varies depending on the wavelength, the position where transmitted light after passing through the antireflection film is shifted due to the wavelength, and aberration 12 occurs. If the positional deviation due to this aberration is large, there may be a problem that the optical design after passing through the antireflection film becomes complicated and that a precise optical design becomes difficult. Since the antireflection film has an average thickness of 0.2 μm to 4 μm, which is much thinner than the conventional antireflection film, the positional deviation due to aberration is extremely small.

  FIG. 5 is a partially enlarged cross-sectional view of an example of a concavo-convex structure layer according to an embodiment of the present invention. The distance (minimum) 15 from the bottom surface 13 of the concave-convex structure layer to the rear surface 6 of the concave-convex structure layer formed by transferring from the mold provided on one surface of the concave-convex structure layer 1, and the concave-convex structure from the bottom surface 13 of the concave-convex structure layer. A difference from the distance (maximum) 14 to the layer back surface 6 is a thickness variation 16 of the uneven structure layer. Moreover, the arithmetic mean of the distance from the concave bottom point 13 to the concave-convex structure layer back surface 6 is the thickness variation average.

  The average thickness variation is preferably set to be equal to or less than the wavelength used. Assuming use in the visible light region, the average thickness variation is preferably 100 nm or less, and more preferably 50 nm or less. Moreover, when the use in an ultraviolet light region is also assumed, the average thickness variation is preferably 50 nm or less, more preferably 10 nm or less. An average thickness variation of 100 nm or less is preferable from the viewpoint of reducing the appearance of uneven color when used as an antireflection film.

  The thickness of the uneven structure layer 1 is the thickness from the back surface of the uneven structure layer to the top of the convex portion. For example, as shown in FIG. 2, the thickness 11 of the concavo-convex structure layer 1 is such that the vertices of the convex portions are extracted from the highest one to several (for example, the fifth), and the average height 10 of the extracted vertices The dimensions can be up to the back surface.

Hereinafter, the present invention will be described based on examples.
First, synthesis examples of the block copolymer (a), the aromatic-containing homopolymer (b), and the poly (meth) acrylate homopolymer (c) are shown.

<Synthesis of block copolymer (a)>
[Synthesis Example 1]
980 g of dehydrated and degassed tetrahydrofuran (hereinafter also referred to as “THF”) as a solvent in a 2 L flask, and a hexane solution (about 0.16 mol / liter) of n-butyllithium (hereinafter also referred to as “n-BuLi”) as an initiator. L) 0.72 mL, 20.8 g of styrene dehydrated and degassed as a monomer, and stirred for 30 minutes while cooling to −78 ° C. in a nitrogen atmosphere, and then dehydrated and degassed as a second monomer 39.6 g of methyl acid (hereinafter also referred to as “MMA”) was added and stirred for 4 hours. Thereafter, the reaction solution was added to a container containing 3 L of denatured alcohol (Solmix AP-1 manufactured by Nippon Alcohol Sales Co., Ltd.) with stirring, and the precipitated polymer was vacuum-dried overnight at room temperature. After completion of the polymerization of polystyrene, 3 ml of the reaction solution was collected before adding MMA. GPC analysis identified it as a polystyrene with a molecular weight of 380,000.

The GPC apparatus, column, and standard polystyrene used are as follows.
Device: HLC-8220 manufactured by Tosoh Corporation
Eluent: Chloroform 40 ° C
Column: Tosoh Corporation trade name TSKgel SuperHZ2000, TSKgel SuperHZM-N In-line flow rate: 1, 0 ml / min
Reference material for molecular weight calibration: TSK standard polystyrene (12 samples) manufactured by Tosoh Corporation
From the result of nuclear magnetic resonance (NMR) analysis, the molar ratio of the PS portion of the block copolymer to the PMMA portion was 1: 2.12. The NMR apparatus and solvent used are as follows. Apparatus: JNM-GSX400 FT-NMR manufactured by JEOL Ltd.
Solvent: Deuterated chloroform Combined with the GPC results, the block copolymer, the main product, was identified to have a PS moiety Mn of 380,000 and a PMMA moiety Mn of 806,000. This was designated as BC-1.

[Synthesis Example 2]
980 g of dehydrated / degassed THF as a solvent, 0.60 mL of n-BuLi hexane solution (about 0.16 mol / L) as an initiator, and 20.8 g of dehydrated / degassed styrene as a monomer were placed in a 2 L flask. The mixture was stirred for 30 minutes while cooling to −78 ° C. in a nitrogen atmosphere, and then 5.1 g of dehydrated and degassed MMA was added as the second monomer, followed by stirring for 2 hours. Subsequent operations were performed in the same manner as in Synthesis Example 1 to synthesize and characterize the block copolymer. As a result, the block copolymer obtained here was identified as having Mn of PS part of 400,000 and Mn of PMMA part of 80,000. This was designated as BC-2.

[Synthesis Example 3]
490 g of dehydrated and degassed THF as a solvent, 1.15 mL of n-BuLi hexane solution (about 0.16 mol / L) as an initiator, and 20.8 g of dehydrated and degassed styrene as a monomer were placed in a 1 L flask. The mixture was stirred for 30 minutes while cooling to −78 ° C. under a nitrogen atmosphere, and then 5.3 g of dehydrated and degassed MMA was added as the second monomer, followed by stirring for 2 hours. Subsequent operations were performed in the same manner as in Synthesis Example 1 to synthesize and characterize the block copolymer. As a result, the block copolymer obtained here was identified to have a Mn of 150,000 for the PS portion and 36,000 for the PMMA portion. This was designated as BC-3.

[Synthesis Example 4]
490 g of dehydrated and degassed THF as a solvent, 2.15 mL of n-BuLi hexane solution (about 0.16 mol / L) as an initiator, and 20.8 g of dehydrated and degassed styrene as a monomer were placed in a 1 L flask. The mixture was stirred for 30 minutes while cooling to −78 ° C. under a nitrogen atmosphere, and then 6.6 g of dehydrated and degassed MMA as a second monomer was added and stirred for 2 hours. Subsequent operations were performed in the same manner as in Synthesis Example 1 to synthesize and characterize the block copolymer. As a result, the block copolymer obtained here was identified to have a Mn of PS portion of 76,000 and a MMMA of PMMA portion of 22,000. This was designated as BC-4.

<Synthesis of aromatic-containing homopolymer (b)>
[Synthesis Example 5]
In a 500 ml flask, 180 g of methyl ethyl ketone (hereinafter also referred to as MEK) as a solvent, 2.36 g (0.0144 mol) of AIBN as an initiator, and 30.0 g (0.288 mol) of styrene as a monomer were heated to 70 ° C. in a nitrogen stream. The mixture was stirred for 6 hours, and then allowed to cool to room temperature. The reaction mixture was added to 2 L of a mixed solution of Solmix AP-1 and water having a mass ratio of 2: 1 with stirring to precipitate a polymer. After stirring this mixed solution for 1 hour, it filtered using the filter paper and solid content was vacuum-dried at 80 degreeC for 3 hours. The molecular weight and molecular weight distribution were measured by GPC under the same conditions as in the case of the block copolymer. As a result, Mw (weight average molecular weight) was 3,200, and molecular weight distribution (Mw / Mn) was 1.36. This was designated as PS-1.

<Synthesis of poly (meth) acrylate homopolymer (c)>
[Synthesis Example 6]
In a 500 ml flask, put 60 g of MEK as a solvent, 13.8 g (0.06 mol) of 2,2′-azobis (dimethyl isobutyrate) as an initiator, and 20 g (0.20 mol) of methyl methacrylate as a monomer under a nitrogen stream. The mixture was stirred for 5 hours while heating to 70 ° C., and then allowed to cool to room temperature. The reaction mixture was added to 1 L of hexane with stirring to precipitate a polymer. After stirring this for 1 hour, it filtered using the filter paper, and solid content was vacuum-dried at 80 degreeC for 3 hours. As a result of measuring molecular weight and molecular weight distribution by GPC, Mw (weight average molecular weight) was 3,800 and molecular weight distribution (Mw / Mn) was 1.54 (At this time, GPC was measured under the same conditions as the block copolymer). However, Standard PMMAM-H-10 (10 samples) manufactured by Polymer Laboratories was used as a standard substance for molecular weight calibration. This was designated as PMMA-1.

  Next, an example of producing a mold having a concavo-convex structure derived from a sea-island structure by a self-organizing pattern forming material combining a block copolymer, polystyrene, and polymethyl methacrylate synthesized in the present invention will be shown.

[Production Example 1]
Propylene glycol monomethyl ether as a solvent comprising 0.600 g of BC-1 (block copolymer (a)) synthesized according to the above synthesis method and 0.900 g of PMMA-1 (poly (meth) acrylate homopolymer (c)). A self-assembled pattern forming material used as a resist layer was prepared by dissolving in 48.5 g of acetate (hereinafter also referred to as PGMEA) at room temperature.

  A silicon wafer with a silicon oxide film having a thickness of 4 inches and a thickness of 10 nm is spin-coated with this self-assembled pattern forming material at 1900 rpm for 30 seconds, and prebaked at 110 ° C. for 90 seconds to form a film containing the self-assembled pattern forming material. I let you. The film thickness of this film was 100 nm when measured using a Nanospec AFT3000T manufactured by Nanometrics Japan K.K.

Next, the wafer on which the film containing the self-assembled pattern forming material was formed with a hot plate (EC-1200N manufactured by ASONE CORPORATION) was heated at 250 ° C. for 6 minutes and annealed. Thereafter, this wafer was subjected to plasma etching with CF ₄ for 70 seconds under a pressure of 1.0 Pa, an antenna of 50 W, and a bias of 50 W using a plasma etching apparatus (NE-550 manufactured by ULVAC, Inc.). After that, plasma etching with Cl _{2 was} performed for 100 seconds with a pressure of 1.0 Pa, an antenna of 50 W, and a bias of 50 W using the above plasma etching apparatus, and a self-organized pattern of a sea-island structure was transferred to the silicon wafer surface. Thereafter, HD-1100 (manufactured by Daikin Industries, Ltd.) as a release agent was applied to the surface of the silicon wafer onto which the self-organized pattern of the sea-island structure was transferred, and allowed to stand overnight at room temperature, and then HD-ZV ( The excess mold release agent was rinsed with Daikin Industries, Ltd., and the mold release treatment was performed. This was designated as mold 1.

  When surface observation was performed with a field emission scanning electron microscope (FE-SEM) S-4800 (manufactured by Hitachi High-Technologies Corporation), it was confirmed that a sea-island structure pattern was formed on the mold 1 surface. The sea-island structure pattern on the surface of the mold 1 was derived from the self-organized pattern forming material in which the polystyrene portion is an island and the polymethyl methacrylate portion is the sea. When the sea-island structure pattern on the surface of the mold 1 was analyzed using image analysis software A Image-kun (Asahi Kasei Engineering Co., Ltd.), the average pitch was 180 nm and the standard deviation in the average pitch distribution was 22% of the average pitch. Yes, the flat area ratio was 43%.

[Production Example 2]
BC-2 (block copolymer (a)) 0.250 g synthesized according to the above synthesis method and PS-1 (aromatic-containing homopolymer (b)) 0.250 g were added to 24.5 g of the solvent PGMEA at room temperature. A self-assembled pattern forming material used as a resist layer was prepared by dissolving.

  A silicon wafer with a silicon oxide film of φ4 inches and a thickness of 10 nm is spin-coated with this self-organized pattern forming material at 3400 rpm for 30 seconds, and pre-baked at 110 ° C. for 90 seconds to form a film containing the self-organized pattern forming material. I let you. The film thickness of this film was 45 nm when measured using a Nanospec AFT3000T manufactured by Nanometrics Japan K.K.

Next, the wafer on which the film containing the above self-assembled pattern forming material was formed with a hot plate (EC-1200N manufactured by ASONE CORPORATION) was heated at 220 ° C. for 3 minutes and annealed. Thereafter, this wafer was subjected to plasma etching with CF ₄ for 55 seconds using a plasma etching apparatus (NE-550 manufactured by ULVAC, Inc.) with a pressure of 0.5 Pa, an antenna of 50 W, and a bias of 50 W. After that, plasma etching with a mixed gas of Ar 95% and Cl ₂ 5% is performed for 350 seconds at a pressure of 3.0 Pa, an antenna of 50 W, and a bias of 50 W by the above plasma etching apparatus, and the sea island structure is self-organized on the silicon wafer surface. The pattern was transcribed. Thereafter, release treatment was performed in the same manner as in Production Example 1. This was designated as mold 2.

  When the surface was observed by the same method as in Production Example 1, it was confirmed that the sea-island structure pattern was formed on the surface of the mold 2. This sea-island structure pattern on the surface of the mold 2 was derived from a self-organized pattern forming material in which the polystyrene portion was the sea and the polymethyl methacrylate portion was the island. When the sea-island structure pattern on the surface of the mold 2 was analyzed using image analysis software A Image-kun (Asahi Kasei Engineering Co., Ltd.), the average pitch was 220 nm and the standard deviation in the average pitch distribution was 34% of the average pitch. And the flat area ratio was 15%.

[Production Example 3]
0.32 g of BC-2 (block copolymer (a)) synthesized according to the above synthesis method and 0.080 g of PS-1 (aromatic-containing homopolymer (b)) were added to 19.6 g of PGMEA as a solvent at room temperature. A self-assembled pattern forming material used as a resist layer was prepared by dissolving.

  A silicon wafer with a silicon oxide film having a thickness of 4 inches and a thickness of 10 nm is spin-coated with this self-assembled pattern forming material at 4100 rpm for 30 seconds, and prebaked at 110 ° C. for 90 seconds to form a film containing the self-assembled pattern forming material. I let you. The film thickness of this film was 45 nm when measured using a Nanospec AFT3000T manufactured by Nanometrics Japan K.K.

Next, the wafer on which the film containing the above self-assembled pattern forming material was formed with a hot plate (EC-1200N manufactured by ASONE CORPORATION) was heated at 220 ° C. for 3 minutes and annealed. Thereafter, this wafer was subjected to plasma etching with CF ₄ for 55 seconds using a plasma etching apparatus (NE-550 manufactured by ULVAC, Inc.) with a pressure of 0.5 Pa, an antenna of 50 W, and a bias of 50 W. After that, plasma etching with a mixed gas of Ar 95% and Cl ₂ 5% is performed for 150 seconds at a pressure of 3.0 Pa, an antenna of 50 W, and a bias of 50 W by the above plasma etching apparatus, and the sea island structure is self-organized on the silicon wafer surface. The pattern was transcribed. Thereafter, release treatment was performed in the same manner as in Production Example 1. This was designated as mold 3.

  When the surface was observed by the same method as in Production Example 1, it was confirmed that the sea-island structure pattern was formed on the surface of the mold 3. The sea-island structure pattern on the surface of the mold 3 was derived from the self-organized pattern forming material in which the polystyrene portion was the sea and the polymethyl methacrylate portion was the island. When the sea-island structure pattern on the surface of the mold 3 was analyzed using image analysis software A image-kun (manufactured by Asahi Kasei Engineering Co., Ltd.), the average pitch was 100 nm, and the standard deviation in the average pitch distribution was 21% of the average pitch. Yes, and the flat area ratio was 22%.

[Production Example 4]
A self-organized pattern forming material used as a resist layer was prepared by dissolving 0.500 g of BC-3 (block copolymer (a)) synthesized according to the above synthesis method in 24.5 g of PGMEA as a solvent at room temperature.

  A silicon wafer with a silicon oxide film having a thickness of 4 inches and a thickness of 10 nm is spin-coated with this self-assembled pattern forming material at 3370 rpm for 30 seconds, and prebaked at 110 ° C. for 90 seconds to form a film containing the self-assembled pattern forming material. I let you. The film thickness of this film was 45 nm when measured using a Nanospec AFT3000T manufactured by Nanometrics Japan K.K.

Next, the wafer on which the film containing the above self-assembled pattern forming material was formed with a hot plate (EC-1200N manufactured by ASONE CORPORATION) was heated at 220 ° C. for 3 minutes and annealed. Thereafter, this wafer was subjected to plasma etching with CF ₄ for 55 seconds using a plasma etching apparatus (NE-550 manufactured by ULVAC, Inc.) with a pressure of 0.5 Pa, an antenna of 50 W, and a bias of 50 W. After that, plasma etching with Cl ₂ was performed for 100 seconds at a pressure of 1.0 Pa, an antenna of 50 W, and a bias of 50 W using the plasma etching apparatus. Thereafter, plasma etching is performed for 100 seconds with a mixed gas of Ar 95% and Cl ₂ 5% at a pressure of 3.0 Pa, an antenna of 50 W, and a bias of 50 W using the plasma etching apparatus described above, and a self-organization of a sea-island structure on the silicon wafer surface. The pattern was transcribed. Thereafter, release treatment was performed in the same manner as in Production Example 1. This was designated as mold 4.

  When the surface was observed by the same method as in Production Example 1, it was confirmed that the sea-island structure pattern was formed on the surface of the mold 4. This sea-island structure pattern on the surface of the mold 4 was derived from the self-organized pattern forming material in which the polystyrene portion was the sea and the polymethyl methacrylate portion was the island. When the sea-island structure pattern on the surface of this mold 4 was analyzed using image analysis software A image-kun (manufactured by Asahi Kasei Engineering Co., Ltd.), the average pitch was 70 nm and the standard deviation in the average pitch distribution was 21% of the average pitch. Yes, the flat area ratio was 27%.

[Production Example 5]
A self-assembled pattern forming material was prepared by dissolving 0.500 g of BC-4 (block copolymer (a)) synthesized according to the above synthesis method in 24.5 g of PGMEA as a solvent at room temperature.

  A silicon wafer with a silicon oxide film having a thickness of 4 inches and a thickness of 10 nm is spin-coated with this self-assembled pattern forming material at 2800 rpm for 30 seconds, and prebaked at 110 ° C. for 90 seconds to form a film containing the self-assembled pattern forming material. I let you. The film thickness of this film was 45 nm when measured using a Nanospec AFT3000T manufactured by Nanometrics Japan K.K.

Next, the wafer on which the film containing the above self-assembled pattern forming material was formed with a hot plate (EC-1200N manufactured by ASONE CORPORATION) was heated at 220 ° C. for 3 minutes and annealed. Thereafter, this wafer was subjected to plasma etching with CF ₄ for 55 seconds using a plasma etching apparatus (NE-550 manufactured by ULVAC, Inc.) with a pressure of 0.5 Pa, an antenna of 50 W, and a bias of 50 W. After that, plasma etching with a mixed gas of Ar 95% and Cl ₂ 5% is performed for 150 seconds at a pressure of 3.0 Pa, an antenna of 50 W, and a bias of 50 W by the above plasma etching apparatus, and the sea island structure is self-organized on the silicon wafer surface. The pattern was transcribed. Thereafter, release treatment was performed in the same manner as in Production Example 1. This was designated as mold 5.

  When the surface was observed by the same method as in Production Example 1, it was confirmed that the sea-island structure pattern was formed on the surface of the mold 5. The sea-island structure pattern on the surface of the mold 5 was derived from the self-organized pattern forming material in which the polystyrene portion was the sea and the polymethyl methacrylate portion was the island. When the sea-island structure pattern on the surface of the mold 5 was analyzed using image analysis software A image-kun (manufactured by Asahi Kasei Engineering Co., Ltd.), the average pitch was 73 nm and the standard deviation in the average pitch distribution was 29% of the average pitch. Yes, the flat area ratio was 31%.

[Comparative Production Example 1]
A self-assembled pattern forming material was prepared by dissolving 0.500 g of BC-4 (block copolymer (a)) synthesized according to the above synthesis method in 24.5 g of PGMEA as a solvent at room temperature.

  A silicon wafer with a silicon oxide film having a thickness of 4 inches and a thickness of 10 nm is spin-coated with this self-assembled pattern forming material at 2800 rpm for 30 seconds, and prebaked at 110 ° C. for 90 seconds to form a film containing the self-assembled pattern forming material. I let you. The film thickness of this film was 45 nm when measured using a Nanospec AFT3000T manufactured by Nanometrics Japan K.K.

Next, the wafer on which the film containing the self-assembled pattern forming material was formed in an oven in a nitrogen atmosphere was annealed by heating at 210 ° C. for 10 minutes and then at 135 ° C. for 10 hours. Thereafter, this wafer was subjected to plasma etching with CF ₄ for 55 seconds using a plasma etching apparatus (NE-550 manufactured by ULVAC, Inc.) with a pressure of 0.5 Pa, an antenna of 50 W, and a bias of 50 W. After that, plasma etching with Cl ₂ was performed for 100 seconds at a pressure of 1.0 Pa, an antenna of 50 W, and a bias of 50 W using the plasma etching apparatus. Thereafter, release treatment was performed in the same manner as in Production Example 1. This was designated as mold 6.

  When the surface was observed by the same method as in Production Example 1, it was confirmed that the sea-island structure pattern was formed on the surface of the mold 6. This sea-island structure pattern on the surface of the mold 6 was derived from a self-organized pattern forming material in which the polystyrene portion was the sea and the polymethyl methacrylate portion was the island. When the sea-island structure pattern on the surface of the mold 6 was analyzed using image analysis software A Image-kun (manufactured by Asahi Kasei Engineering Co., Ltd.), the average pitch was 33 nm and the standard deviation in the average pitch distribution was 25% of the average pitch. Yes, the flat area ratio was 70%.

  Next, an antireflection film manufactured by a mold having a concavo-convex structure derived from a sea-island structure made of a self-organized pattern forming material combining a synthesized block copolymer, polystyrene, and polymethyl methacrylate will be described.

[Evaluation method]
(1) Thickness average (of antireflection film) (μm)
As shown in FIG. 3, after cutting out the antireflection film to be measured into a rectangle so that the area is maximized in the plane, a straight line is drawn so that the long side and the short side of the cut out rectangle are divided into 5 equal parts, respectively. The center point of each rectangle was positioned. The thickness of the center point was measured using a transmission spectral film thickness meter (Otsuka Electronics Co., Ltd., FE1300) (measurement wavelength 248 nm). The average value of the 25 measured values was taken as the thickness average.
(2) Average thickness variation (nm)
As described above, the surface shape of the uneven surface was measured using AFM for each of the test pieces divided into 25 equal parts. About each test piece, the average value of the distance along the layer thickness direction of an uneven structure layer between the recessed part bottom points was computed. Furthermore, the average value of the average values calculated for the 25 test pieces was defined as the thickness variation average.
(3) Yield strain (%) and tensile elongation (%) of the resin composition as a raw material
Based on JIS K7113, it measured on conditions with a tensile speed of 1 mm / min. For the measurement, AGS-50G manufactured by Shimadzu Corporation was used.
(4) Yield strain (%) and tensile elongation (%) of the concavo-convex structure layer
Based on JIS K7127, it measured on conditions with a tensile speed of 1 mm / min. For the measurement, AGS-50G manufactured by Shimadzu Corporation was used.

<Example 1>
A polymer solution was prepared by dissolving cellulose acetate propionate (CAP 480-20, manufactured by Eastman Chemical Company, yield strain about 4%, tensile elongation about 15%) in ethyl lactate.

  At this time, the concentration of cellulose acetate propionate contained in the polymer solution was 8% by mass. 30 cc of the polymer solution prepared on the mold 1 was dropped and spin-coated on a spin coater under the conditions of a rotation speed of 300 rpm and a rotation time of 30 seconds.

Next, the mold 1 was dried for 5 minutes each on a hot plate at 80 ° C. and 180 ° C., and the dried film was peeled off from the mold 1 to obtain an uneven structure layer (antireflection film) having an area of 78.5 cm ² . The resulting uneven structure layer had an average thickness of 1.5 μm, and the uneven structure layer had an average thickness variation of 61 nm. The center part of the finished concavo-convex structure layer was cut into a 5 cm × 5 cm square, and the thickness average of the cut-out concavo-convex structure layer and the average thickness variation of the concavo-convex structure layer were measured. The average thickness variation of the structural layer was 53 nm. When the cut-out concavo-convex structure layer was observed by AFM, a periodic concavo-convex structure having a height of 150 nm and a period length of 180 nm was formed. The produced concavo-convex structure layer had a yield strain of 4% and a tensile elongation of 15%.

  Next, the concavo-convex structure layer was cut into 5 cm × 5 cm square. A transmission spectral film thickness meter (Otsuka Electronics Co., Ltd., FE1300) is formed at the center of each square divided into 25 equal parts by drawing a straight line so that an arbitrary side of the cut-out square and a side perpendicular to the one side are equally divided into 5 parts. ). Measurements were performed using wavelengths of 248 nm and 365 nm. When the transmittance at a wavelength of 248 nm at the 25 points was measured, the difference between the point with the highest transmittance and the point with the lowest transmittance was 3%. Further, when the transmittance at a wavelength of 365 nm at the 25 points was measured, the difference between the point with the highest transmittance and the point with the lowest transmittance was 5%.

  Next, when the concavo-convex structure layer cut out to 5 cm × 5 cm square was attached to a transparent sphere having a diameter of 8 cm, a folding part was not generated, and it could be attached to the transparent sphere without any gap. When the transparent sphere with the concavo-convex structure layer was observed with the naked eye, the color unevenness was hardly visible.

<Example 2>
CYTOP CTX-809SP2 (trade name, produced by Asahi Glass Co., Ltd., yield strain of about 5%, tensile elongation of about 175%), which is a solution containing an amorphous fluororesin having a perfluoroalkyl ether ring structure as a film material, is perfluorotri Dilution adjustment was performed with butylamine (Fluorinert FC-43, trade name, manufactured by Sumitomo 3M Limited). At this time, the concentration of the amorphous fluororesin having a perfluoroalkyl ether ring structure contained in the polymer solution was 3% by mass. After 30 cc of the polymer solution prepared on the mold 2 was dropped, it was spin-coated on a spin coater under the conditions of a rotation speed of 300 rpm and a rotation time of 50 seconds.

Next, the mold 2 was dried on a hot plate at 80 ° C. and 180 ° C. for 5 minutes each, and the dried film was peeled off from the mold 1 to obtain an uneven structure layer (antireflection film) having an area of 78.5 cm ² . The resulting uneven structure layer had an average thickness of 0.7 μm, and the uneven structure layer had an average thickness variation of 10 nm. The center part of the finished concavo-convex structure layer was cut out with a square of 5 cm × 5 cm, and the thickness average of the cut-out concavo-convex structure layer and the average thickness variation of the concavo-convex structure layer were measured. The thickness average of the concavo-convex structure layer was 0.7 μm. The average thickness variation of the structural layer was 5 nm. When the cut-out concavo-convex structure layer was observed by AFM, a periodic concavo-convex structure having a height of 100 nm and a period length of 220 nm was formed. The produced concavo-convex structure layer had a yield strain of 5% and a tensile elongation of 175%.

  Next, the concavo-convex structure layer was cut into 5 cm × 5 cm square. A transmission spectral film thickness meter (Otsuka Electronics Co., Ltd., FE1300) is formed at the center of each square divided into 25 equal parts by drawing a straight line so that an arbitrary side of the cut-out square and a side perpendicular to the one side are equally divided into 5 parts. ). Measurements were performed using wavelengths of 248 nm and 365 nm. When the transmittance at a wavelength of 248 nm at the 25 points was measured, the difference between the point with the highest transmittance and the point with the lowest transmittance was 1%. Further, when the transmittance at a wavelength of 365 nm at the 25 points was measured, the difference between the point with the highest transmittance and the point with the lowest transmittance was 0.5%.

  Next, when the concavo-convex structure layer cut out to 5 cm × 5 cm square was attached to a transparent sphere having a diameter of 8 cm, no folding part was formed, and the concavo-convex structure layer could be attached to the transparent sphere without any gap. When the transparent sphere with the concavo-convex structure layer was observed with the naked eye, the color unevenness was not visible at all.

<Example 3>
A concavo-convex structure layer was produced by the same production method as in Example 2 except that the mold 3 was used as the mold. The resulting uneven structure layer had an average thickness of 0.7 μm, and the uneven structure layer had an average thickness variation of 10 nm. The center part of the finished concavo-convex structure layer was cut into a 5 cm × 5 cm square, and the thickness average of the cut-out concavo-convex structure layer and the average thickness variation of the concavo-convex structure layer were measured. The thickness average of the concavo-convex structure layer was 0.7 μm The average thickness variation of the structural layer was 5 nm. When the cut-out concavo-convex structure layer was observed by AFM, a periodic concavo-convex structure having a height of 100 nm and a period length of 100 nm was formed. The produced concavo-convex structure layer had a yield strain of 5% and a tensile elongation of 175%.

  Next, the concavo-convex structure layer was cut into 5 cm × 5 cm square. A transmission spectral film thickness meter (Otsuka Electronics Co., Ltd., FE1300) is formed at the center of each square divided into 25 equal parts by drawing a straight line so that an arbitrary side of the cut-out square and a side perpendicular to the one side are equally divided into 5 parts. ). Measurements were performed using wavelengths of 248 nm and 365 nm. When the transmittance at a wavelength of 248 nm at the 25 points was measured, the difference between the point with the highest transmittance and the point with the lowest transmittance was 1%. Further, when the transmittance at a wavelength of 365 nm at the 25 points was measured, the difference between the point with the highest transmittance and the point with the lowest transmittance was 0.5%.

  Next, when the concavo-convex structure layer cut out to 5 cm × 5 cm square was attached to a transparent sphere having a diameter of 8 cm, no folding part was formed, and the concavo-convex structure layer could be attached to the transparent sphere without any gap. When the transparent sphere with the concavo-convex structure layer was observed with the naked eye, the color unevenness was not visible at all.

<Example 4>
A concavo-convex structure layer was produced by the same production method as in Example 2 except that the mold 4 was used as the mold. The resulting uneven structure layer had an average thickness of 0.7 μm, and the uneven structure layer had an average thickness variation of 10 nm. The center part of the finished concavo-convex structure layer was cut into a 5 cm × 5 cm square, and the thickness average of the cut-out concavo-convex structure layer and the average thickness variation of the concavo-convex structure layer were measured. The thickness average of the concavo-convex structure layer was 0.7 μm The average thickness variation of the structural layer was 5 nm. When the cut-out uneven structure layer was observed by AFM, a periodic uneven structure having a height of 100 nm and a period length of 70 nm was formed. The produced concavo-convex structure layer had a yield strain of 5% and a tensile elongation of 175%.

  Next, the concavo-convex structure layer was cut into 5 cm × 5 cm square. A transmission spectral film thickness meter (Otsuka Electronics Co., Ltd., FE1300) is formed at the center of each square divided into 25 equal parts by drawing a straight line so that an arbitrary side of the cut-out square and a side perpendicular to the one side are equally divided into 5 parts. ). Measurements were performed using wavelengths of 248 nm and 365 nm. When the transmittance at a wavelength of 248 nm at the 25 points was measured, the difference between the point with the highest transmittance and the point with the lowest transmittance was 1%. Further, when the transmittance at a wavelength of 365 nm at the 25 points was measured, the difference between the point with the highest transmittance and the point with the lowest transmittance was 0.5%.

  Next, when the concavo-convex structure layer cut out to 5 cm × 5 cm square was attached to a transparent sphere having a diameter of 8 cm, no folding part was formed, and the concavo-convex structure layer could be attached to the transparent sphere without any gap. When the transparent sphere with the concavo-convex structure layer was observed with the naked eye, the color unevenness was not visible at all.

<Example 5>
A concavo-convex structure layer was produced by the same production method as in Example 2 except that the mold 5 was used as the mold. The resulting uneven structure layer had an average thickness of 0.7 μm, and the uneven structure layer had an average thickness variation of 10 nm. The center part of the finished concavo-convex structure layer was cut out with a square of 5 cm × 5 cm, and the thickness average of the cut-out concavo-convex structure layer and the average thickness variation of the concavo-convex structure layer were measured. The thickness average of the concavo-convex structure layer was 0.7 μm. The average thickness variation of the structural layer was 5 nm. When the cut-out concavo-convex structure layer was observed by AFM, a periodic concavo-convex structure having a height of 80 nm and a period length of 70 nm was formed. The produced concavo-convex structure layer had a yield strain of 5% and a tensile elongation of 175%.

  Next, the concavo-convex structure layer was cut into 5 cm × 5 cm square. A transmission spectral film thickness meter (Otsuka Electronics Co., Ltd., FE1300) is formed at the center of each square divided into 25 equal parts by drawing a straight line so that an arbitrary side of the cut-out square and a side perpendicular to the one side are equally divided into 5 parts. ). Measurements were performed using wavelengths of 248 nm and 365 nm. When the transmittance at a wavelength of 248 nm at the 25 points was measured, the difference between the point with the highest transmittance and the point with the lowest transmittance was 1%. Further, when the transmittance at a wavelength of 365 nm at the 25 points was measured, the difference between the point with the highest transmittance and the point with the lowest transmittance was 0.5%.

  Next, when the concavo-convex structure layer cut out to 5 cm × 5 cm square was attached to a transparent sphere having a diameter of 8 cm, no folding part was formed, and the concavo-convex structure layer could be attached to the transparent sphere without any gap. When the transparent sphere with the concavo-convex structure layer was observed with the naked eye, the color unevenness was not visible at all.

<Comparative Example 1>
A polymer solution was prepared by dissolving polymethyl methacrylate (Mitsubishi Rayon Co., Ltd., no yield strain, tensile elongation of about 6%) in a toluene solution. At this time, the concentration of polymethyl methacrylate contained in the polymer solution was 6% by mass.

  After performing silane coupling on the surface of the mold 1, the produced polymer solution was dropped on a 30 cc film formation substrate, and spin-coated on a spin coater under conditions of a rotation speed of 300 rpm and a rotation time of 50 seconds. Next, the film formation substrate was dried on a hot plate at 80 ° C. and 180 ° C. for 5 minutes each, and when the dried film was peeled off from the film formation substrate, the film was broken.

<Comparative example 2>
The concavo-convex structure is the same as in Example 2 except that the amount of the polymer solution deposited on the film formation substrate and the rotation speed of the spin coater are adjusted so that the average thickness of the concavo-convex structure layer at 5 cm × 5 cm square is 5.0 μm. A structural layer was prepared. The dropping amount of the polymer solution was 30 cc, the rotation speed of the spin coater was 500 rpm, and the rotation time was 30 seconds.

  When the concavo-convex structure layer cut out to 5 cm × 5 cm square was attached to a transparent sphere having a diameter of 8 cm, a folded part was formed, and a gap was formed.

  The antireflection film produced by the mold of the present invention is an antireflection film excellent in shape followability, such as an image display device such as a touch panel, a liquid crystal display panel, a plasma display or an organic EL display, a projection optical system such as a projector, an optical lens, etc. It can be suitably used for an optical element such as an observation optical system, an imaging optical system such as a camera, a tip of a light emitting part of a polarizing beam splitter or a light emitting diode, and a surface of a solar cell panel.

DESCRIPTION OF SYMBOLS 1 Uneven structure layer 2 Thin film layer 3 Coating layer 4 Antireflection film 5 Uneven structure derived from sea-island structure based on self-organized pattern forming material 6 Uneven structure layer back surface 7 Antireflection film surface 8 Antireflection film back surface 9 Extraction line 10 Vertex Average height 11 Thickness of concavo-convex structure layer 12 Position shift due to aberration 13 Concave bottom point 14 Distance from concave bottom point to back surface (maximum)
15 Distance from the bottom of the recess to the back (minimum)
16 Unevenness structure layer thickness variation 17 Periodic interval

Claims (15)

  The average pitch of the convex or concave portions of the concave and convex shape on the mold surface is 40 nm or more and 250 nm or less, the standard deviation in the average pitch distribution is 10% or more and 40% or less of the average pitch, and the mold A mold for producing an antireflection film, wherein an area ratio of a flat portion on a surface is 0% or more and 50% or less. The following steps:
(1) forming a mask layer on the substrate surface;
(2) forming a resist layer containing the block copolymer (a) containing the aromatic ring-containing polymer (poly1) and the poly (meth) acrylate (poly2) as a block component on the mask layer;
(3) annealing the resist layer in an air atmosphere to phase-separate the block copolymer (a) to form a self-organized pattern of a sea-island structure;
(4) a step of selectively removing a poly (meth) acrylate portion in the phase-separated resist layer by etching;
(5) A step of etching using the resist layer patterned with the remaining aromatic ring-containing polymer portion as a mask, and transferring the pattern of the patterned resist layer to the mask layer;
(6) etching the patterned mask layer to transfer the pattern of the patterned mask layer to the substrate surface; and (7) the patterned resist layer and the patterned mask layer. A step of treating the patterned substrate surface with a release agent after removing the substrate;
The manufacturing method of the mold for anti-reflective film manufacture of Claim 1 containing this.   The resist layer further includes an aromatic ring-containing homopolymer (b) synthesized from a monomer constituting the poly1 and / or a poly (meth) acrylate homopolymer (c) synthesized from a monomer constituting the poly2. The method according to claim 2.   The method of Claim 2 or 3 whose mass ratio of the said poly1 and the said poly2 is 10: 90-90: 10.   The method as described in any one of Claims 2-4 whose number average molecular weights of the said block copolymer (a) are 5 million or more and 5 million or less.   The number average molecular weight Mn1 of the poly1 is from 30,000 to 1,000,000, and the number average molecular weight Mn2 of the poly2 is from 10,000 to 1,500,000. The method according to item.   The resist layer includes a homopolymer (b) when the Mn1 is larger than the Mn2, and the resist layer includes a homopolymer (c) when the Mn1 is smaller than the Mn2. The method described.   The mass ratio of the block copolymer (a) to the entire resist layer is 30% by mass to 90% by mass, and the total mass ratio of the homopolymer (b) and the homopolymer (c) is 10% by mass to 70%. The method as described in any one of Claims 2-7 which is the mass% or less.   The method according to claim 2, wherein the etching in the step (6) is performed by isotropic reactive ion etching using an etching gas containing Ar.   The method according to any one of claims 2 to 9, wherein the poly1 is polystyrene and the poly2 is polymethyl methacrylate.   The method of Claim 10 that the ratio of the said polystyrene in the said block copolymer is 10 mass% or more and 95 mass% or less.   The method according to any one of claims 2 to 11, wherein the substrate is Si. The method according to claim ₂ , wherein the mask layer is SiO ₂ .   It manufactures using the mold for anti-reflective film manufacture of Claim 1, It consists of resin whose yield distortion is 1% or more, and tensile elongation is 10% or more, and thickness average is 0.2 micrometer- Antireflection film which is 4 μm.   The antireflection film according to claim 14, wherein the resin is an amorphous fluororesin having a perfluoroalkyl ether ring structure.

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