WO2014163041A1 - Transfer film and substrate with relief structure - Google Patents

Abstract

A transfer film configured from a support film having a relief pattern on the surface and a transfer layer containing a siloxane composition, said siloxane composition containing a photoacid generator or a photobase generator. The purpose of the present invention is to provide a transfer film or cross-linked transfer film for easily forming a siloxane layer, the surface relief pattern of which does not easily collapse, on a substrate with a large area. The invention also provides a substrate with a relief structure having a cross-linked transfer layer.

Description

Transfer film and substrate with uneven structure

The present invention relates to a transfer film for forming a siloxane layer having a concavo-convex shape on a surface thereof on a large-area substrate and a substrate with a concavo-convex structure having a concavo-convex shape formed on the surface.

Various substrates such as various semiconductor substrates, glass substrates, and metal substrates are used as substrates for LEDs, solar cell substrates, and liquid crystal display devices. In recent years, in order to improve the functions of substrates and products obtained by using substrates, it is required to perform pattern processing to impart functions such as antistatic, antireflection, antifouling, and light scattering to the substrate surface. ing.

The pattern processing of the substrate surface is widely performed by the lithography method or the imprint method. Lithography is a technology that forms a desired shape on the surface of a substrate by irradiating the photosensitive resin coated on the substrate with light through a mask and then developing it. This is a very important technology in the semiconductor manufacturing process. It is. On the other hand, the imprint method is a method of imparting a shape to the surface by pressing a mold having a shape inverted from a target shape against a workpiece. Specifically, an ultraviolet curable resin or a thermoplastic resin is applied on the substrate, and a shape is imparted by pressing a mold against the resin. In the case of using an ultraviolet curable resin, the resin is cured by irradiating with ultraviolet rays in a state where the mold is pressed, and then the mold is peeled to obtain a target shape. When using a thermoplastic resin, the thermoplastic resin applied on the substrate is heated above the glass transition temperature of the thermoplastic resin, the heated mold is pressed on the resin, and then cooled to below the glass transition temperature, The mold is peeled off to obtain the target shape. The imprint method is a method that can be patterned by a very simple process of pressing a mold, and therefore is widely studied. In addition, since the pattern obtained by these methods consists of organic substances, when pattern formation with an inorganic material is required, the substrate itself may be etched using the pattern obtained by these methods as a resist. .

On the other hand, the functional layer formed by patterning the surface is required to have very high heat resistance and light transmittance depending on the process and use of the substrate. For example, in the case of a sapphire substrate used for LED manufacturing, a gallium nitride (GaN) layer as a light emitting layer needs to be epitaxially grown on the substrate, and the substrate is exposed to a high temperature exceeding 1,000 ° C. in the process. In addition, when used in applications such as LEDs and solar cells, it becomes very hot during use or is exposed to severe sunlight exposed to sunlight in an outdoor environment. Light transmittance is required.

A siloxane material is attracting attention as one of the materials that satisfy these requirements. Siloxane is a material similar to glass, characterized in that the bond between silicon and oxygen is continuous and does not have a crystal structure, and is less susceptible to decomposition and yellowing at higher temperatures than organic resins. Furthermore, the siloxane material can be produced by a so-called sol-gel method in which a solution containing silicon alkoxide is heated at a high temperature of several hundred degrees. When a siloxane material is produced using the sol-gel method, it can be converted into siloxane by pouring a silicon alkoxide solution into a mold and then curing. Therefore, it is easy to use a material with high heat resistance and relatively low energy. It is possible to form a pattern. A method in which a solution containing silicon alkoxide has been applied onto a substrate and solidified by pressing a mold (Patent Document 1), and a pattern is formed with a resist using a resin having a siloxane structure imparted with ultraviolet curability An example in which an uneven shape layer of siloxane is formed by the method (Patent Document 2) has been reported.

JP 11-314927 A JP 2006-154037 A

In the sol-gel method, an alkoxysilane having a silanol group, or a siloxane oligomer / polymer obtained by dehydration polycondensation thereof is heated to remove the solvent, and further, dehydration condensation of a hydroxyl group or alkoxy group directly bonded to a silicon atom or In this method, siloxane is obtained by proceeding with crosslinking by dealcoholization condensation. In order to obtain a material having high heat resistance and light resistance by this method, it is important to advance a crosslinking reaction as much as possible to form many siloxane bonds. However, when the siloxane layer shaped to have a concavo-convex shape is heated to several hundred degrees in order to sufficiently advance the crosslinking reaction, the viscosity of the uncrosslinked siloxane material decreases, and the surface shape of the siloxane layer collapses. was there.

In view of these problems, an object of the present invention is to provide a transfer film for easily forming on a substrate a siloxane layer capable of maintaining a shape formed on a surface even when heated at a high temperature.

The transfer film of the present invention that achieves the above-mentioned object is a transfer film in which a transfer layer containing a siloxane composition is laminated on a support film having a concavo-convex shape on the surface, and the siloxane composition is a photoacid generator Or it is a transfer film containing a photobase generator.

According to the present invention, a transfer layer containing a siloxane composition having a concavo-convex shape excellent in heat resistance and light resistance can be easily formed on the substrate surface.

(A) It is a cross-sectional schematic diagram of the transfer film containing the support body film which has regular uneven | corrugated shape. (B) It is a cross-sectional schematic diagram of the transfer film containing the support body film which has random uneven | corrugated shape. (C) It is a cross-sectional schematic diagram of the transfer film containing the support body film which has an uneven | corrugated shape which has a flat area | region in an uneven | corrugated shaped convex part and a recessed part. (D) It is a cross-sectional schematic diagram of the transfer film containing the support body film which has spherical uneven | corrugated shape. (A) It is a cross-sectional schematic diagram of the board | substrate with an uneven structure which has a regular shape. (B) It is the cross-sectional schematic of the board | substrate with an uneven structure which has random uneven | corrugated shape. (C) It is the cross-sectional schematic of the board | substrate with an uneven structure which has a flat area | region in the convex part and concave part of an uneven shape. (D) It is a cross-sectional schematic diagram of the board | substrate with an uneven structure which has a spherical uneven shape. It is an FT-IR spectrum for calculating P1 / P2.

Hereinafter, the transfer film of the present invention will be described in more detail with reference to the drawings.

As shown in FIG. 1, the transfer film of the present invention comprises a support film 1 having a concavo-convex shape on the surface and a transfer layer 2 comprising a siloxane composition laminated on the surface having the concavo-convex shape of the support film. Composed. After the substrate is covered with the transfer film so that the transfer layer 2 side of the transfer film is in contact with the substrate, only the support film is removed from the transfer film, so that the surface of the substrate 9 is transferred to the transfer layer as shown in FIG. A laminate coated with 2 can be obtained. Since the surface of the transfer layer 2 has a concavo-convex shape in which the concavo-convex shape of the support film 1 is reversed, a substrate with a concavo-convex structure having a concavo-convex shape on the surface is obtained. In this way, it is possible to easily form an uneven shape on the surface of a large area substrate.

[Uneven surface shape of support film]
The uneven surface shape of the support film may be a geometric shape or a random shape. Examples of the surface uneven shape include a prism shape, a diffraction grating, a moth-eye shape, a polygonal prism shape, a polygonal cone shape, a cylindrical shape, a conical shape, a hemispherical shape, a truncated pyramid shape, a truncated cone shape, and an inverted shape thereof. This is not the case.

1 (a) to 1 (d) show examples of the transfer film of the present invention. Fig.1 (a) is an example of the transfer film containing the support body film which has regular uneven | corrugated shape. FIG.1 (b) is an example of the transfer film containing the support body film which has a random uneven | corrugated shape. FIG.1 (c) is an example of the transfer film containing the support body film which has an uneven | corrugated shape which has an uneven | corrugated shaped convex part and a flat area | region in a recessed part. FIG.1 (d) is an example of the transfer film containing the support body film which has a spherical uneven | corrugated shape. By laminating the transfer films shown in FIGS. 1A to 1D on a substrate and transferring the transfer layer to the substrate, the substrate with an uneven structure shown in FIGS. 2A to 2D can be obtained.

The surface irregularity of the support film has a typical pitch of preferably 0.01 to 50 μm, more preferably 0.05 to 30 μm, and further preferably 0.1 to 20 μm. The representative pitch refers to the pitch of a repeated shape when the uneven shape is a geometric shape, and the average value of 10 arbitrarily selected pitches when it is a random shape. As shown in FIG. 1, the pitch is a horizontal distance 3 between points indicating the maximum depths of two adjacent concave portions in the transfer layer. When the bottom of the concave shape is flat as shown in FIG. 1C or curved as shown in FIG. 1D, the horizontal distance 3 between the center points is set as the pitch. When the representative pitch is smaller than 0.01 μm, the transfer layer and the support film are difficult to peel off due to the large surface area of the interface, or the target shape cannot be obtained because it easily bites foreign matter. There is. On the other hand, when the representative pitch is larger than 50 μm, the function may not be exhibited because the density of the uneven shape is low.

The aspect ratio of the concavo-convex shape of the support film is preferably 0.01 to 3, more preferably 0.05 to 2, still more preferably 0.3 to 2, and 0.5 to 1 is particularly preferred. The aspect ratio is a value obtained by dividing the depth 5 of the concave portion by the width 4 of the concave portion of the support film, as described with reference to FIG. When the concave bottom is flat as shown in FIG. 1 (c) or curved as shown in FIG. 1 (d), the width 4 of the concave portion takes the maximum distance among the concave portions. Shall. The depth 5 of the recess is a vertical distance between the minimum position of the recess of the support film and the adjacent maximum position. When the heights of the local maximum positions on both sides of the concave portion are different from each other, the vertical distance formed by the concave portion on the higher side and the concave portion is defined as the depth of the concave portion. Moreover, when the aspect ratio of the uneven | corrugated shape of a support body film is not constant, the average value of the aspect ratio of 10 uneven | corrugated shapes arbitrarily selected is taken as a value of an aspect ratio. When the aspect ratio of the concavo-convex shape is smaller than 0.01, the concavo-convex shape is very low, and the shape effect may be difficult to obtain. On the other hand, when the aspect ratio is larger than 3, the releasability between the support film and the transfer layer is lowered, and it becomes difficult to form an accurate shape by tearing or falling when transferring. There is a case.

The representative pitch and aspect ratio of the support film can be measured by observation with a scanning electron microscope. When observing with a scanning electron microscope, if the surface irregularities are arranged in a line, cut with a microtome in a direction perpendicular to the extending direction of the line and observe the cross section. When the uneven shape on the surface is discretely arranged, cut with a microtome so as to pass through the center position of the discrete uneven shape, and observe the cross section. In addition, since the surface of the transfer layer transferred onto the substrate has an inverted shape of the uneven shape of the support film, the uneven structure on the surface of the transfer layer after transfer may be observed. The uneven structure on the surface of the transfer layer can be observed as described later using a laser microscope, AFM, or the like.

The method for forming the uneven shape on the support film is not particularly limited, and it is possible to apply a known method such as a thermal imprint method, a UV imprint method, coating, etching, or patterning by a self-organized product. .

[Support film]
The thickness of the support film used in the present invention is preferably 5 to 500 μm, more preferably 25 to 300 μm, and further preferably 40 to 125 μm. If the thickness is less than 5 μm, the transfer layer may be transferred and the substrate may not be accurately coated. On the other hand, when the thickness exceeds 500 μm, the support film becomes rigid and may not be able to follow the shape of the substrate. The distance of the portion having the maximum thickness including the uneven shape on the surface is defined as the thickness of the support film. That is, when it demonstrates using FIG. 1, the distance 6 of the maximum point of the uneven | corrugated shaped convex part of a support film and the surface on the opposite side of a support film is made into the thickness of a support film.

The material of the support film is not particularly limited as long as it can withstand the solvent removal of the transfer layer and the heating during the transfer to the substrate. For example, polyester resins such as polyethylene terephthalate, polyethylene-2,6-naphthalate, polypropylene terephthalate, polybutylene terephthalate, cyclohexanedimethanol copolymerized polyester, isophthalic acid copolymerized polyester, spiroglycol copolymerized polyester, fluorene copolymerized polyester; Polyolefin resins such as polystyrene, polypropylene, polyisobutylene, polybutene, polymethylpentene, and cyclic polyolefin copolymers; polyamide resins, polyimide resins, polyether resins, polyesteramide resins, polyetherester resins, acrylic resins, polyurethane resins, polycarbonate resins Alternatively, polyvinyl chloride resin or the like can be used. A polyolefin resin or an acrylic resin is preferable from the viewpoint of achieving both the coatability of the siloxane sol serving as the transfer layer and the releasability of the transfer layer and the support film.

Further, the support film may be a single layer or a multilayer. In the case of a multilayer structure, the surface in contact with the transfer layer is preferably a polyolefin resin or an acrylic resin.

Furthermore, in order to bring the surface of the support film into an appropriate state, a layer made of a resin other than the above can be laminated. Furthermore, in order to give coatability and releasability to the surface of the support film in contact with the transfer layer, a base conditioner, an undercoat agent, a silicone release coating agent, a fluorine release coating agent, etc. You may perform the process which apply | coats, and may carry out the sputtering process to the surface of noble metals, such as gold | metal | money and platinum. Here, the appropriate state means that the surface free energy of the surface on which the transfer layer of the support film is formed is 23 to 70 mN / m. By adjusting the surface state so that the surface free energy falls within this range, it is possible to prevent the occurrence of defects such as repellency when forming the transfer layer on the support film, and the support during transfer The mold releasability between the film and the transfer layer can be improved.

[Transfer layer material]
In the transfer film of the present invention, the transfer layer contains a siloxane composition, and the siloxane composition contains a photoacid generator or a photobase generator. The siloxane composition is a composition containing a siloxane compound, and may contain organosilane or a hydrolysis product thereof in addition to the siloxane compound. A siloxane compound is a compound that contains two or more consecutive siloxane bonds in the structure. The siloxane compound may have an organic functional group directly bonded to a silicon atom as a partial structure, or may partially include a silica structure not having an organic functional group directly bonded to a silicon atom. The weight average molecular weight of the siloxane compound is not particularly limited, but is preferably 500 to 100,000 in terms of polystyrene measured by GPC. The siloxane compound can be synthesized by solidifying a siloxane sol synthesized by subjecting one or more organosilanes represented by the following chemical formula (1) to a hydrolysis reaction and a polycondensation reaction by heating and pressing.

In the formula, R ₁ represents any _one of hydrogen, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, and an aryl group having 6 to 15 carbon atoms, and a plurality of R ₁ may be the same or different. May be. R ₂ represents any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, an acyl group having 1 to 6 carbon atoms, and an aryl group having 6 to 15 carbon atoms, and a plurality of R ₂ may be the same or different. . n represents an integer of 0 to 3.

In the organosilane represented by the chemical formula (1), the alkyl group, alkenyl group and aryl group of R ₁ may be either unsubstituted or substituted, and can be selected according to the characteristics of the composition. Specific examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, t-butyl group, n-hexyl group, n-decyl group, trifluoromethyl group, 3, 3 , 3-trifluoropropyl group, 3-glycidoxypropyl group, 2- (3,4-epoxycyclohexyl) ethyl group, [(3-ethyl3-oxetanyl) methoxy] propyl group, 3-aminopropyl group, 3 -Mercaptopropyl group, 3-isocyanatopropyl group and the like. Specific examples of the alkenyl group include a vinyl group, a 3-acryloxypropyl group, and a 3-methacryloxypropyl group. Specific examples of the aryl group include phenyl, tolyl, p-hydroxyphenyl, 1- (p-hydroxyphenyl) ethyl, 2- (p-hydroxyphenyl) ethyl, 4-hydroxy-5- (p -Hydroxyphenylcarbonyloxy) pentyl group, naphthyl group and the like.

In the organosilane represented by the chemical formula (1), the alkyl group, acyl group and aryl group of R ₂ may be either unsubstituted or substituted, and can be selected according to the characteristics of the composition. Specific examples of the alkyl group include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, n-pentyl group, and n-hexyl group. Specific examples of the acyl group include an acetyl group, a propinoyl group, a butyroyl group, a pentanoyl group, and a hexanoyl group. Specific examples of the aryl group include a phenyl group and a naphthyl group.

N in the chemical formula (1) represents an integer of 0 to 3. A tetrafunctional silane when n = 0, a trifunctional silane when n = 1, a bifunctional silane when n = 2, and a monofunctional silane when n = 3.

Specific examples of the organosilane represented by the chemical formula (1) include tetrafunctional silanes such as tetramethoxysilane, tetraethoxysilane, tetrabutoxysilane, tetraacetoxysilane, and tetraphenoxysilane; methyltrimethoxysilane, methyltriethoxy Silane, methyltriisopropoxysilane, methyltrin-butoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltriisopropoxysilane, ethyltrin-butoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-butyltrimethoxysilane, n-butyltriethoxysilane, n-hexyltrimethoxysilane, n-hexyltriethoxysilane, decyltrimethoxysilane, vinyltrimethoxysilane, vinylto Ethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, trifluoromethyltrimethoxysilane, trifluoromethyl Triethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltri Trifunctional silanes such as ethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-mercaptopropyltriethoxysilane; dimethyldimethoxysilane, dimethyldie Xysilane, dimethyldiacetoxysilane, di-n-butyldimethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-methacryloxypropylmethyl Bifunctional such as dimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-aminopropyldiethoxymethylsilane And monofunctional silanes such as trimethylmethoxysilane and tri-n-butylethoxysilane.

These organosilanes may be used alone or in combination of two or more. In order to give flexibility effective in preventing cracks on the transfer film, monofunctional silane, bifunctional silane and trifunctional having an organic functional group directly bonded to a silicon atom with respect to the entire organosilane It is preferable that at least one of silanes is contained in an amount of 5 to 100% in terms of the number of silicon atoms.

On the other hand, in order to improve the heat resistance of the concavo-convex shape formed on the substrate, at least one of trifunctional silane and tetrafunctional silane is 40 to 100 in terms of the number of silicon atoms with respect to the whole organosilane. %, Preferably 70 to 100%, more preferably 90 to 100%.

Here, the silicon atom number ratio is described by taking a tetrafunctional silane as an example, and the tetrafunctional silane represented by n = 0 in the above chemical formula (1) with respect to the number of silicon atoms contained in the transfer layer. It is the ratio of the number of silicon atoms.

The number of organic functional groups n of the organosilane represented by the chemical formula (1) can be analyzed by ²⁹ SiNMR. ^As measured by ²⁹ SiNMR, n = 0 tetrafunctional silane is −90 to −120 ppm, n = 1 trifunctional silane is −55 to −70 ppm, n = 2 bifunctional silane is 0 to −25 ppm, A monofunctional silane with n = 3 shows a signal at 20-0 ppm. All the area values of these signals are summed to obtain the total area value of the number of silicon atoms contained in the transfer layer. By dividing the area value of the signal of each of the monofunctional silane, the bifunctional silane, the trifunctional silane, and the tetrafunctional silane by the total area value of the number of silicon atoms, each silicon atom number ratio is obtained.

In addition, silica particles may be added to the transfer layer in order to improve scratch resistance and hardness. In addition, the transfer layer is made of acrylic for improving mold release properties, leveling agents, and resin-based substrates for improving mold releasability and wettability. Resin etc. may be included.

[Photoacid generator and photobase generator]
The siloxane composition constituting the transfer layer contains a photoacid generator or a photobase generator capable of generating an acid or a base by light irradiation.

In the siloxane composition, a crosslinking reaction proceeds by dehydration condensation of the hydroxyl group at the terminal of the siloxane compound as represented by the chemical formula (2) to form a network.

In the formula, R ₁ represents any _one of hydrogen, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, and an aryl group having 6 to 15 carbon atoms, and a plurality of R ₁ may be the same or different. May be. R ₂ represents any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, an acyl group having 1 to 6 carbon atoms, and an aryl group having 6 to 15 carbon atoms, and a plurality of R ₂ may be the same or different. . m represents a natural number.

In the prior art, in order to impart high heat resistance to the concavo-convex shape layer formed of the siloxane composition on the substrate, the hydroxyl group at the terminal of the siloxane compound contained in the siloxane composition is cross-linked to increase the molecular weight, It is necessary to form a network of density. However, when a heat treatment is performed to advance the dehydration condensation reaction, the uneven shape layer formed of a siloxane compound having a low molecular weight is more likely to cause a decrease in viscosity than the dehydration condensation, and the uneven shape is flattened. There was a case.

In order to solve this problem, the inventors have intensively studied, and as a result, came up with the idea of proceeding the crosslinking reaction of the siloxane compound under a temperature condition that does not cause a decrease in viscosity before the heat treatment of the uneven layer. . Specifically, it is a method of suppressing a decrease in viscosity during heat treatment by promoting a dehydration condensation reaction of a siloxane compound in an unheated state with an acid catalyst or a base catalyst to form a network. The pot life of the siloxane sol used for forming the transfer layer on the support film can be extended by generating an acid or base having a catalytic effect by light irradiation. Further, from the viewpoint of solubility in siloxane sol and generation efficiency of acid having a catalytic effect, a photoacid generator is preferable, and a photobase generator is preferable from the viewpoint that the siloxane crosslinking reaction rate can be further increased. I found.

Photoacid generators include sulfonium photoacid generators, iodonium salt photoacid generators, selenium salt photoacid generators, diazonium salt photoacid generators, phosphoric acid photoacid generators, and triazine photoacid generators. Generators, acetophenone derivative compounds, metallocene complexes, iron arene complexes, and the like are known. From the viewpoint of solubility in a solution and generation efficiency of an acid component, a sulfonium photoacid generator is preferred. Specific examples of the photoacid generator include CPI-100P, CPI-101A, CPI-200K, CPI-210S manufactured by San Apro Co., Ltd., WPAG-336, WPAG-367, WPAG-370, WPAG manufactured by Wako Pure Chemical Industries, Ltd. -469, WPI-113, WPI-116, WPI-124, WPI-170, CIPAG-II, EEPAG manufactured by Ibitsu Corporation, PAI-101, DTS-102, DTS-103, DTS-105 manufactured by Midori Chemical Co., Ltd. SP-170 manufactured by Adeka Corporation can be mentioned.

On the other hand, the photobase generator is roughly classified into a nonionic photobase generator and an ionic photobase generator. From the viewpoint of the solubility of the solution, the generation efficiency of the base component, and the strength of the generated base, an ionic photobase generator, particularly one that generates a pKa8 or higher base compound is preferred. Specific examples of the photobase generator include PBG-SA1, SA-1B manufactured by San Apro Co., Ltd., WPBG-266, WPBG-300, WPBG-082, WPBG-140 manufactured by Wako Pure Chemical Industries, Ltd. , EITMG and the like. In the photoacid generator or photobase generator, from the viewpoint of the pot life of the siloxane sol, the wavelength at which the generation of acid or base is activated is preferably 365 nm or less.

The amount of the photoacid generator contained in the transfer layer is preferably 0.2 to 5.0% by mass, and preferably 0.3 to 2.5% by mass when the entire transfer layer is 100% by mass. Is more preferably 0.4 to 0.9% by mass. When the content of the photoacid generator is less than 0.2% by mass, the amount of acid generated by the photoacid generator is small, and it may be difficult to obtain a sufficient shape retention effect. On the other hand, when the content of the photoacid generator is more than 5.0% by mass, a portion having a different refractive index is generated in the transfer layer due to a local reaction due to acid generation or a residue after the reaction of the photoacid generator. As a result, it may become cloudy or the leveling property may be lowered due to an increase in viscosity due to the progress of the cross-linking reaction, and the transfer layer may easily be uneven in thickness or undulate.

The amount of the photobase generator contained in the transfer layer is preferably 0.05 to 10% by mass, more preferably 0.1 to 5% by mass, when the entire transfer layer is 100% by mass. When the content of the photobase generator is less than 0.05% by mass, the amount of base generated by the photobase generator is small, and it may be difficult to obtain a sufficient shape retention effect. On the other hand, when the content of the photobase generator is more than 10% by mass, the photobase generator cannot be completely dissolved and a uniform transfer layer cannot be formed, or the viscosity of the coating solution increases due to the crosslinking reaction. The transfer layer may become cloudy due to a decrease in life or a residue of the photobase generator.

Especially, the uneven thickness of the transfer layer is easily reflected in the uneven thickness of the remaining film of the transfer layer. The residual film thickness of the transfer layer is a minimum value of the thickness between the surface of the transfer layer in contact with the substrate and the surface of the transfer layer in contact with the support film. To explain with reference to the drawings, the distances represented by 8 in FIGS. 1A to 1D are the remaining film thicknesses. Further, a value obtained by dividing the residual film thickness difference represented by the difference between the maximum value and the minimum value obtained by measuring the residual film thickness at 10 points by the average value of the residual film thickness, that is, (((residual film The residual film thickness non-uniformity (%) is defined as the difference in residual film thickness indicated by the difference between the maximum value and the minimum value obtained by measuring the thickness at 10 points) / (average value of residual film thickness)) × 100.

The residual film thickness unevenness is preferably less than 25%, more preferably less than 15%. When the residual film thickness unevenness is 25% or more, the transfer layer may be caused to cause transfer unevenness or defects when pressed in contact with the substrate, or the shape size may be reduced when etching the uneven shape formed on the substrate. It may become uneven. The residual film thickness of the transfer layer is measured by cutting the transfer film with a microtome and imaging and measuring the cross section with a scanning electron microscope.

[Formation of transfer layer]
As a method of forming a transfer layer on a support film, a method of coating a siloxane sol diluted with a solvent on a support film and drying it is easy to adjust the film thickness, and the thickness of the support film, etc. It is preferable because it is hardly affected.

The siloxane sol contains a siloxane composition and a solvent. The solvent is not particularly limited as long as it has a solubility capable of obtaining a solution of a siloxane sol having an appropriate concentration to be used for coating, but it is an organic solvent from the point that repellency hardly occurs on the film. Is preferred. For example, high boiling alcohols such as diacetone alcohol and 3-methyl-3-methoxy-1-butanol; glycols such as ethylene glycol and propylene glycol; ethylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, Propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether, propylene glycol monobutyl ether, diethyl ether, diisopropyl ether, di-n-butyl ether, diphenyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, The Ethers such as tylene glycol ethyl methyl ether and dipropylene glycol dimethyl ether; ketones such as methyl ethyl ketone, methyl isobutyl ketone, diisopropyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, 2-heptanone and 3-heptanone; dimethylformamide, dimethylacetamide Amides such as ethyl acetate, butyl acetate, ethyl acetate, ethyl cellosolve acetate, esters such as 3-methyl-3-methoxy-1-butanol acetate; aromatics such as toluene, xylene, hexane, cyclohexane, mesitylene, diisopropylbenzene Aliphatic or aliphatic hydrocarbons; γ-butyrolactone, N-methyl-2-pyrrolidone, dimethyl sulfoxide, etc. .

From the viewpoint of the solubility of the siloxane composition and the coating property of the siloxane sol, diacetone alcohol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monomethyl ether acetate, diisobutyl ether, di-n- A solvent selected from butyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, dipropylene glycol dimethyl ether, methyl isobutyl ketone, diisobutyl ketone and butyl acetate is preferred.

As a method for applying the siloxane sol, for example, gravure coating, roll coating, spin coating, die coating, bar coating, screen coating, blade coating, air knife coating, dip coating, spray coating, and the like may be selected as appropriate. .

After coating, the support film coated with the siloxane sol is dried by heating or reduced pressure. In the case of heating and drying, the heating temperature is preferably 20 ° C. or higher and 180 ° C. or lower. When the heating temperature is lower than 20 ° C., a long time may be required for drying. On the other hand, when heated to a temperature higher than 180 ° C., the transfer film loses its flexibility due to polymerization of siloxane due to heating, cracks occur, curl due to the difference in thermal expansion coefficient between the support film and the transfer layer, The uneven shape of the film surface may collapse. In the case of drying under reduced pressure, the reduced pressure condition may be set as appropriate as long as the shape of the transfer film does not collapse, and the pressure is preferably reduced to 10 kPa. Furthermore, you may heat and dry simultaneously with pressure reduction.

The thickness of the transfer layer is preferably from 0.01 to 20 μm, more preferably from 0.03 to 10 μm, still more preferably from 0.05 to 5 μm. When the thickness of the transfer layer is smaller than 0.01 μm, the height of the concavo-convex shape formed on the substrate is lowered, and it may be difficult to obtain the effect of the concavo-convex shape. On the other hand, when the thickness of the transfer layer is greater than 20 μm, when heat treatment is performed on the substrate, film stress may occur and cracks may occur. The thickness of the transfer layer is the portion where the transfer layer is thickest on the transfer film, that is, the support layer when it is placed horizontally with the opposite side of the transfer film to the opposite side. The distance between the lowest position of the recess on the surface of the boundary with the transfer layer 2 on the film 1 and the outermost surface of the transfer layer is defined as the thickness 7 of the transfer layer. The thickness of the transfer layer is measured by cutting the transfer film with a microtome and imaging and measuring the cross section with a scanning electron microscope.

[Transfer method]
A method for transferring a transfer layer to a substrate using the transfer film of the present invention will be described. The surface of the transfer film of the present invention on the transfer layer side is brought into contact with the substrate to obtain a laminate, and after pressing and / or heating the laminate, the support film is peeled off to form an uneven shape on the substrate surface. The transfer layer can be applied. This process is called transfer.

Examples of the pressure applied during transfer include, but are not limited to, nip rolls and press machines. The pressure applied to the laminate is preferably 1 kPa to 50 MPa. If the pressure is less than 1 kPa, transfer defects are likely to occur due to the inclusion of bubbles between the substrate and the transfer film. If the pressure exceeds 50 MPa, the concavo-convex shape of the mold film may be broken or the substrate may be cracked.

Further, when pressurizing, a buffer material can be used between the support film of the laminate and a pressure plate, a pressure roll, or the like. By using the cushioning material, the transfer layer can be transferred with high accuracy without entraining air or the like. As the buffer material, fluorine rubber, silicon rubber, ethylene propylene rubber, isobutylene isoprene rubber, acrylonitrile butadiene rubber, or the like can be used. In addition, in order to sufficiently adhere the transfer layer to the substrate, heating can be performed together with pressurization.

As a method of obtaining a substrate with a concavo-convex structure in which a cross-linked transfer layer having a concavo-convex shape on the surface is obtained by using a transfer method, (1) by irradiating the transfer film with light to cross-link the transfer layer After obtaining the cross-linked transfer film, the cross-linked transfer film is laminated on the substrate, and then the support film is peeled off. (2) After the transfer film is laminated on the substrate, light is irradiated to cross-link the transfer layer. Then, a method of peeling the support film, (3) After laminating the transfer film on the substrate, peeling the support film to obtain a laminate composed of the substrate and the transfer layer, followed by irradiation with light There is a method of crosslinking the transfer layer.

[Crosslinked transfer film]
After forming a transfer layer on a support film having a concavo-convex shape, by irradiating with light, the photoacid generator or photobase generator contained in the siloxane composition is activated to generate an acid or base, The siloxane compound contained in the transfer layer can be crosslinked. Here, the crosslinked transfer layer is referred to as a crosslinked transfer layer. A transfer film in which the transfer layer is crosslinked is called a crosslinked transfer film.

The wavelength of the light to be irradiated is in a wavelength range suitable for the absorption band of the photoacid generator or photobase generator contained, but it is possible to prevent coloration due to residues or absorption bands of the photoacid generator or photobase generator, and siloxane. From the viewpoint of extending the pot life of the sol, a wavelength band of 365 nm or less is preferable.

The total amount of light irradiation is preferably 100 to 5,000 mJ / cm ² , more preferably 200 to 3,000 mJ / cm ² , and still more preferably 300 to 1,500 mJ / cm ² . If the total amount of light irradiation is less than 100 mJ / cm ² , the photoacid generator or photobase generator may not be sufficiently activated, and the crosslinking reaction may not proceed sufficiently. On the other hand, when the total amount of light irradiation is more than 5,000 mJ / cm ² , irradiation may take time or the support film may be deteriorated.

[Evaluation with FT-IR]
The crosslinked transfer film of the present invention is a crosslinked transfer film in which a crosslinked transfer layer containing a siloxane composition is laminated on a support film having a concavo-convex shape, and P1 / P2 obtained from an FT-IR spectrum of the crosslinked transfer layer. The value of is 0.12 or more. In FT-IR spectrum of the crosslinked transfer film as shown in FIG. ^3, a peak attributed to the stretching vibration of the siloxane bond Si-O-Si is observed 960cm ^-1 ~ 1,250cm -1. The line segment connecting the minima 14 and 2090 cm @ ^-1 minimum value 15 in the vicinity of the vicinity of 960 cm ^-1 which is the opposite ends of the peak as a baseline, the peak area between 1,020Cm ^-1 from 960 cm ^-1 Similarly, let P1 be a peak area between 960 cm ⁻¹ and 1,200 cm ⁻¹ . Since siloxane is an amorphous substance, the bond angle of Si—O—Si varies. Therefore, the FT-IR spectrum is observed as a broad waveform in which peaks corresponding to various coupling angles are superimposed in the vicinity of 960 to 1,250 cm ⁻¹ . In the superimposed peak, the position of a low wave number close to 960 cm ⁻¹ is attributed to siloxane having a high crosslinking density and close to crystallinity. Therefore, the value of P1 / P2 shows the ratio of the thing with a high crosslinking density in all the siloxane bonds.

The cross-linked transfer film of the present invention preferably has a P1 / P2 value of 0.12 or more. When the value of P1 / P2 is less than 0.12, the ratio of the one having a high crosslinking density in the siloxane bond is low. Therefore, when the substrate having the concavo-convex structure obtained by transferring the transfer layer is processed at a high temperature In addition, the uneven structure is broken by heat.

The FT-IR spectrum for calculating P1 and P2 is, for example, FTIR Fourier Transform Infrared Spectrophotometer FT / IR-6100typeA manufactured by JASCO Corporation, and using an ATR reflector equipped with a Ge prism. Measurement can be performed under the conditions of 400 to 4,000 cm ⁻¹ , resolution of 4 cm ⁻¹ , and number of integrations of 128 times. The spectrum obtained by the measurement is analyzed using an analysis program in the measurement software. First, after the spectrum obtained with ATR correction, near 960 cm ^-1 is a peak of the siloxane bonds in the primary differential, read the wave number takes a minimum value in the vicinity of 2090 cm @ ^-1 (in FIG. 3, 15) . Using the read wave number as the base calculation range, the areas of P1 and P2 are calculated in a manner in which the area below the base line is ignored, and further P1 / P2 is calculated. At this time, the area calculation range of P1 is 960 to 1,020 cm ⁻¹ , and the calculation range of P2 is 960 to 1,200 cm ⁻¹ .

On the other hand, when light is irradiated after laminating the transfer film on the substrate, the surface on the transfer layer side of the transfer film of the present invention is brought into contact with the substrate to pressurize and / or heat, and substrate / transfer layer / support A laminate of the film is obtained, and the laminate is crosslinked by generating an acid from a photoacid generator contained in the transfer layer or a base from the photobase generator by irradiating the laminate with light. When performing light irradiation, as long as the substrate transmits light, light may be irradiated from either side of the substrate or the support film, or light may be irradiated from both sides. According to this aspect, since the transfer layer can be crosslinked with the photoacid generator or the photobase generator within the concavo-convex shape of the support film, it is advantageous for maintaining the concavo-convex shape. In addition, since the dehydration reaction is easily promoted between the substrate and the transfer layer, it is advantageous for improving the adhesion between the substrate and the transfer layer. Moreover, since it can preserve | save in the state before bridge | crosslinking, an effect can be anticipated also in the life extension of a transfer film. The total amount of light irradiated on the laminated body of the substrate / transfer layer / support film preferably 200 ~ 10,000mJ / cm ^2, more preferably 300 ~ 8,000mJ / cm ^2, is 500 ~ 5,000 mJ / cm ² Further preferred. If the total irradiation amount is less than 200 mJ / cm ² , the energy may be insufficient to activate the photoacid generator or photobase generator, and the activation may not be sufficient. When the total irradiation amount is greater than 10,000 mJ / cm ² , a long time may be required for activation.

In addition, when the support film is peeled off from the laminate in which the transfer film is laminated on the substrate and then irradiated with light, the surface on the transfer layer side of the transfer film of the present invention is brought into contact with the substrate and pressurized and / or heated. Then, a laminate of the substrate / transfer layer / support film is obtained, and the transfer layer is crosslinked by irradiating light to the substrate / transfer layer laminate obtained by peeling the support film from the laminate. To do. When performing light irradiation, as long as the substrate transmits light, light may be irradiated from either side of the substrate or the transfer layer, or light may be irradiated from both sides. According to this aspect, since the transfer layer can be directly irradiated with light, energy loss due to the support film can be reduced, and acid or base can be generated more efficiently. Moreover, since it can preserve | save in the state before bridge | crosslinking, an effect can be anticipated also in the life extension of a transfer film. The total amount of light irradiated on the laminated body of the substrate / transfer layer is preferably 100 ~ 10,000 / cm ^2, more preferably 200 ~ 8,000 mJ / cm ^2, more preferably 300 ~ 5,000mJ / cm ^2. When the total irradiation amount is less than 100 mJ / cm ² , the energy may be insufficient to activate the photoacid generator or photobase generator, and the activation may not be sufficient. When the total irradiation amount is more than 10,000 mJ / cm ² , it may be required for a long time for activation.

[Heat treatment of substrate with uneven structure]
A substrate with a concavo-convex structure in which a cross-linked transfer layer having a concavo-convex shape on the surface and containing a siloxane composition is laminated on the substrate can be obtained with higher heat resistance by heat treatment at a high temperature. The heat treatment may be performed on the substrate / transfer layer / support film laminate or the substrate / transfer layer two-layer laminate from which the support film has been peeled off. In order to obtain a two-layer laminate of substrate / transfer layer, when the support film is peeled in advance before the heat treatment, it is preferably peeled at a temperature equal to or lower than the temperature during pressurization in the transfer step. When the temperature at the time of peeling is higher than the temperature at the time of pressurization, the shape of the transfer layer may collapse, or the releasability from the support film may be reduced.

The heat treatment temperature can be appropriately set according to the heat resistance, chemical resistance and reliability required for the cross-linked transfer layer having an uneven shape. For example, when a substrate with a concavo-convex structure is processed into a patterned sapphire substrate used in LED production, the temperature of the heat treatment is preferably 1,000 to 1,500 ° C. because the temperature is about 1,100 ° C. in the epitaxial growth process. 1,100 to 1,400 ° C. is more preferable. When the heat treatment temperature is less than 1,000 ° C., the formed uneven shape may not be maintained during the epitaxial growth process and may collapse. When the heat treatment temperature exceeds 1,500 ° C., cracks may occur during the heat treatment, or curl may occur due to a difference in thermal expansion from the substrate.

On the other hand, when the concavo-convex structure of the substrate with a concavo-convex structure is used as a mask for etching an inorganic material or a crystal material having a low etching rate, the material to be etched is used as the substrate, but the concavo-convex structure has an etching rate higher than that of the substrate. Need to be low. For this purpose, it is effective to disperse the organic components in the transfer layer to form a dense silicon dioxide film. Therefore, the heat treatment temperature is preferably 700 to 1,500 ° C. When the heat treatment temperature is lower than 700 ° C., organic substances may remain in the transfer layer or may not be sufficiently densified, and the etching rate may not be lowered. If the heat treatment temperature is higher than 1,500 ° C., cracks may occur in the transfer layer.

Furthermore, when a substrate with a concavo-convex structure is used to control the reflection and transmission of light on the surface of a solar cell or the like, it is necessary to adjust the heat resistance of several hundred degrees, high light transmission, and refractive index. In this case, the heat treatment temperature is preferably 150 to 700 ° C., more preferably 200 to 400 ° C. When the heat treatment temperature is lower than 150 ° C., the crosslinking reaction of siloxane is insufficient and the heat resistance may be lowered, or the shape may be easily broken. On the other hand, when the heat treatment temperature exceeds 700 ° C., the organic functional group directly bonded to the silicon atom of siloxane is lost, and the refractive index may not be adjusted. During heat treatment, in order to prevent cracking and peeling of the substrate and transfer layer due to a rapid temperature change, pre-baking is performed at a temperature lower than the high temperature heat treatment temperature or plasma irradiation is performed to preliminarily crosslink. You may make it progress.

[Application example of substrate with uneven structure]
Since the substrate with a concavo-convex structure thus obtained has a concavo-convex shape with high heat resistance, it can be used as an antireflection plate or a light scattering plate assumed to be used in a high temperature environment. Further, when the transfer layer is sufficiently cross-linked, it can be used as an etching resist film, so that it can also be used for manufacturing a patterned sapphire substrate that contributes to improving the light extraction efficiency of the LED. Furthermore, it can be used for the outermost surface of an LED or the like to improve the light extraction efficiency, or can be used for a member such as a solar cell panel to improve the power generation efficiency.

The present invention will be specifically described based on examples, but the present invention is not limited to the examples.

(1) Evaluation of the shape of the concavo-convex structure (1-1) Preparation of substrate After removing dust adhering to the surface of the substrate with a blower, plasma irradiation was performed at 15000 VAC for 5 minutes using a tabletop vacuum plasma device manufactured by Sakai Semiconductor Co., Ltd. did. Thereafter, the substrate immersed in pure water was washed twice at 45 kHz for 10 minutes using a three-frequency ultrasonic cleaner No. VS-100III manufactured by ASONE CORPORATION. After cleaning, pure water adhering to the substrate was removed with a blower.

(1-2) Transfer Method The transfer layer surface of a 20 mm × 20 mm size transfer film or a cross-linked transfer film is brought into contact with the transfer target prepared in (1-1), pressed, and then the support film is peeled off to form irregularities. A structured substrate was obtained.

(1-3) Heat treatment method The substrate with a concavo-convex structure obtained as described above is placed in a Yamato Scientific Co., Ltd. muffle furnace FP410 set at a furnace temperature of 50 ° C., at a predetermined temperature of 10 ° C./min. After the temperature was raised to 1, heat treatment was performed at a predetermined temperature for 1 hour. After the treatment, the furnace was allowed to cool to 25 ° C.

(1-4) Shape Observation and Evaluation Method The shape of the concavo-convex structure formed on the substrate was evaluated by the concavo-convex width size and the concavo-convex height. Here, the uneven width size is a horizontal distance 10 between two adjacent local minimum values as shown in FIG. The uneven height is a vertical distance 11 between the adjacent maximum and minimum positions of the uneven shape as shown in FIG. When the heights between the minimum positions on both sides of the top are different from each other, the vertical distance between the minimum position on the higher side and the top is defined as the uneven height.

When both the uneven width size and the uneven height were 1 μm or more, they were measured with a laser microscope VK9700 manufactured by Keyence Corporation. The measurement magnification was 1,500 times when the uneven width size and uneven height were smaller than 1 μm and less than 20 μm, and 500 times when 20 μm or more.

On the other hand, when any of the uneven width size and the uneven height was less than 1 μm, observation and measurement were performed in a tapping mode of an atomic force microscope model number ICON ICON manufactured by Bruker AXS Co., Ltd. The observation visual field was defined by the concave / convex width size in order to put a plurality of concave / convex shapes into the observation visual field. That is, when the uneven width size is less than 0.02 μm, the measurement visual field is 0.1 μm × 0.1 μm, and when it is 0.02 μm or more and less than 0.1 μm, 0.5 μm × 0.5 μm, 0.1 μm or more and 0.2 μm When it is less than 2 μm × 2 μm, when it is 0.2 μm or more, it is 5 μm × 5 μm. For the measurement, the software NanoScope Analysis Ver. 1.40 was used. As the measurement points, five points were arbitrarily selected, and values obtained by averaging the measurement values at the five points were defined as the uneven height and the uneven width, respectively.

The shape evaluation after the heat treatment is the height retention ratio of the unevenness height before and after the heat treatment when the unevenness height before the heat treatment is 100% (that is, (the unevenness height after the heat treatment / the unevenness height before the heat treatment) × 100 (%)), the unevenness width before and after heat treatment when the unevenness width before heat treatment is 100% is defined as the width retention ratio (that is, (unevenness width after heat treatment / unevenness width before heat treatment) × 100 (%)) The shape retention was evaluated. The criteria for shape evaluation after the heat treatment were defined and described as follows.
4: Both the height retention ratio and the width retention ratio are 90% or more and 100% or less 3: At least one of the height retention ratio and the width retention ratio is 50% or more and less than 90% 2: The height retention ratio and the width retention ratio are both Less than 50%, and at least one is 10% or more and less than 50% 1: Both the height retention ratio and the width retention ratio are less than 10%.

(2) Evaluation of uneven thickness of transfer film remaining film The transfer film was cut with a microtome so that the thickness direction could be observed, and the remaining film thickness was measured by observing the cross section with a scanning electron microscope. The measurement magnification is 100,000 times when the transfer layer thickness is less than 0.5 μm, 50,000 times when the transfer layer thickness is 0.5 μm or more and less than 1.0 μm, and 20,000 when 1.0 μm or more and less than 2.0 μm. In the case of 2.0 times or more and less than 10 μm, 5,000 times, in the case of 10 μm or more and less than 20 μm, 2,500 times, and in the case of 20 μm or more, 500 times. The number of measurement points was arbitrary 10, and the residual film thickness unevenness was calculated by the method described in the column of [Photoacid generator and photobase generator], and the value was evaluated according to the following evaluation criteria.
3: Less than 15% thickness variation 2: More than 15% thickness variation and less than 25% 1: More than 25% thickness variation.

(3) Crosslinking evaluation by FT-IR The FT-IR spectrum of a cross-linked transfer film or a transfer layer on a substrate with a concavo-convex structure was measured using a FT-IR Fourier transform infrared spectrophotometer FT / IR- manufactured by JASCO Corporation. Measurement was performed using 6100 type A. Measurement, using the measurement program software Spectra Manager Version2 of JASCO Corporation, using ATR PRO650G equipped with Ge made prism, wave number range 400 ~ 4,000 cm ^-1, resolution ^{4 cm -1,} 128 cumulative of Performed under conditions. From the spectrum obtained by the measurement, the areas of P1 and P2 were determined by the method described in the specification, and P1 / P2 was calculated.

[Example 1]
A support polyolefin film having a concavo-convex shape formed by thermal imprinting on one side of a 100 μm-thick “Zeonor Film” (registered trademark) model number ZF14 made by Nippon Zeon Co., Ltd., which is a cyclic polyolefin resin, was used. For the thermal imprinting, a prism-shaped nickel electroforming mold having a pitch of 5 μm and a height of 2.5 μm was used. After holding the mold pressed against the support film for 30 seconds under the conditions of a mold temperature of 180 ° C. and a pressure of 2.0 MPa, the mold was cooled to 100 ° C. to release the pressure, and the support film was released. The apparatus used was a 2-ton vacuum heater press model number MKP-150TV-WH manufactured by Mikado Technos.

Photo-acid produced by San-Apro Co., Ltd. was prepared by dissolving polymethylsilsesquioxane SR-13 manufactured by Konishi Chemical Industries, Ltd. in propylene glycol monopropyl ether (hereinafter referred to as PGPE) to a concentration of 20% by mass. A siloxane sol was prepared by adding a generator CPI-200K (sulfonium photoacid generator) so that the solid content was 0.5 mass% relative to the polymethylsilsesquioxane ratio. The obtained siloxane sol was applied to the surface of the support film with the irregular shape formed using a spin coater model 1H-DX2 manufactured by Mikasa Co., Ltd., and dried at 90 ° C. for 2 minutes to obtain a transfer film. The transfer layer surface of the obtained transfer film was irradiated with UV of 500 mJ / cm ² to activate the photoacid generator of the transfer layer to promote the crosslinking reaction of siloxane, thereby obtaining a crosslinked transfer film. For UV irradiation, a light source unit Multilight ML-251A / B for USHIO INC. Exposure apparatus was used.

A cross-linked transfer film was laminated on non-alkali glass EAGLE 2000 (30 mm × 30 mm, thickness 0.63 mm) manufactured by Corning Japan Co., Ltd. prepared as a substrate so that the surface of the cross-linked transfer layer was in contact with the substrate. Further, a model number F200 manufactured by Kinyo Co., Ltd. was laminated as a buffer material on the support film surface of the crosslinked transfer film, and pressed for 10 seconds at a press temperature of 20 ° C. and a press pressure of 1.38 MPa in the configuration of glass substrate / crosslinked transfer film / buffer material. The apparatus used was a 2-ton vacuum heater press model number MKP-150TV-WH manufactured by Mikado Technos. Then, the film as a support was peeled off at room temperature to obtain a substrate with a concavo-convex structure comprising a glass substrate / crosslinked transfer layer.

[Example 2]
A crosslinked transfer film and a substrate with a concavo-convex structure were obtained in the same manner as in Example 1 except that the solid content of the photoacid generator CPI-200K was 0.2% by mass.

[Example 3]
A crosslinked transfer film and a substrate with a concavo-convex structure were obtained in the same manner as in Example 1 except that the solid content of the photoacid generator CPI-200K was 5.0 mass%.

[Example 4]
A crosslinked transfer film and a substrate with a concavo-convex structure were obtained in the same manner as in Example 1 except that the solid content of the photoacid generator CPI-200K was 0.3% by mass.

[Example 5]
A crosslinked transfer film and a substrate with a concavo-convex structure were obtained in the same manner as in Example 1 except that the solid content of the photoacid generator CPI-200K was 2.5% by mass.

[Example 6]
A crosslinked transfer film and a substrate with an uneven structure were obtained in the same manner as in Example 1 except that the solid content of the photoacid generator CPI-200K was 0.4 mass%.

[Example 7]
A crosslinked transfer film was obtained in the same manner as in Example 1 except that the solid content of the photoacid generator CPI-200K was 0.9% by mass. Subsequently, the non-alkali glass EAGLE2000 (30 mm × 30 mm, thickness 0.63 mm) manufactured by Corning Japan Co., Ltd. prepared as a substrate was laminated so that the surface of the cross-linked transfer layer was in contact with the substrate. Pressed with a cross-linked transfer film configuration. The press was laminated using a VA-420H type laminator manufactured by Taisei Laminator Co., Ltd. at a roll thrust of 0.2 MPa, a conveyance speed of 3 m / min, and a press temperature of 20 ° C. After lamination, the support film was peeled off to obtain a substrate with a concavo-convex structure comprising a glass substrate / crosslinked transfer layer.

[Example 8]
A crosslinked transfer film was obtained in the same manner as in Example 1 except that the UV irradiation amount was 100 mJ / cm ² . Thereafter, a substrate with an uneven structure was obtained in the same manner as in Example 7.

[Example 9]
A crosslinked transfer film was obtained in the same manner as in Example 1 except that the UV irradiation amount was 200 mJ / cm ² . Thereafter, a substrate with an uneven structure was obtained in the same manner as in Example 7.

[Example 10]
A substrate with a concavo-convex structure was obtained in the same manner as in Example 1 except that the support film was an acrylic resin film and the UV irradiation amount to the transfer film was 1,500 mJ / cm ² . The support film was produced by the following method. On a PET film “Lumirror” (registered trademark) model number U34 manufactured by Toray Industries, Inc. having a thickness of 100 μm, an ultraviolet curable acrylic resin “Aronix” (registered trademark) UV3701 manufactured by Toagosei Co., Ltd. was applied in a thickness of 10 μm. After superposing a nickel electroforming mold having a prism shape with a pitch of 5 μm and a height of 2.5 μm on the ultraviolet curable acrylic resin layer, UV of 1,000 mJ / cm ² is irradiated from the PET film surface to form an acrylic system. The resin was cured. Thereafter, the interface between the mold and the acrylic resin was peeled off to obtain a support film having a concavo-convex shape formed on the surface of the acrylic resin.

[Example 11]
A film having a thickness of 60 μm formed by melt extrusion of a resin of “TOPAS” (registered trademark) model 6013 manufactured by Polyplastics Co., Ltd., which is a cyclic polyolefin resin, is used as a support film, and the UV irradiation amount to the transfer film is determined. Except having set it as 300 mJ / cm < ² >, it carried out similarly to Example 1, and obtained the board | substrate with an uneven structure.

[Example 12]
Instead of performing UV irradiation in Example 1, instead of performing UV irradiation at 1,000 mJ / cm ² from the support film side of the substrate / transfer film laminate obtained by laminating the transfer film on the substrate instead. A substrate with an uneven structure was obtained in the same manner as in Example 1.

[Example 13]
Transfer of the substrate / transfer layer laminate obtained by peeling the support film from the substrate / transfer film laminate obtained by laminating the transfer film on the substrate instead of UV irradiation in Example 1 A substrate with a concavo-convex structure was obtained in the same manner as in Example 1 except that UV irradiation was performed at 750 mJ / cm ² from the layer side.

[Example 14]
The mold used for thermal imprinting has a shape of a regular square pyramid having a side of 20 μm and a height of 10 μm, and having a pitch of 20 μm that is adjacent to each other and adjoining the apex and side of each other, and a siloxane sol A substrate with an uneven structure was obtained in the same manner as in Example 1 except that the polymethylsilsesquioxane concentration was 40% by mass.

[Example 15]
The same procedure as in Example 14 was performed except that the heat treatment temperature of the substrate with an uneven structure was 600 ° C.

[Example 16]
The mold used for thermal imprinting was such that convex square pillars each having a side of 2 μm and a height of 700 nm were arranged in a lattice shape with a pitch of 4 μm, and the polymethylsilsesquioxane concentration of the siloxane sol was 15 A substrate with a concavo-convex structure was obtained in the same manner as in Example 1 except that the mass% was used.

[Example 17]
The same procedure as in Example 16 was performed except that the heat treatment temperature of the substrate with an uneven structure was 600 ° C.

[Example 18]
A substrate with a concavo-convex structure was obtained in the same manner as in Example 1 except that the mold used for thermal imprinting was a convex hemispherical shape having a diameter of 4 μm, a height of 2 μm, and a pitch of 4.5 μm.

[Example 19]
A substrate with a concavo-convex structure was obtained in the same manner as in Example 1 except that the mold used for thermal imprinting was a blazed diffraction grating with a pitch of 556 nm.

[Example 20]
A mold used for thermal imprinting has a shape in which spheroids having a convex width of 0.25 μm, a height of 0.3 μm, and a pitch of 0.3 μm are discretely arranged in a regular triangle shape (hereinafter referred to as a spheroid). A substrate with a concavo-convex structure was obtained in the same manner as in Example 1 except that the discretely arranged shape was referred to as a moth-eye shape) and the polymethylsilsesquioxane concentration of the siloxane sol was 10% by mass. .

[Example 21]
A mold used for thermal imprinting is supported in the same manner as in Example 1 except that a regular square pyramid having a side of 5 μm and a height of 12 μm is arranged in a regular triangle shape with a pitch of 30 μm. A body film was obtained. In addition, Polyphenylsilsesquioxane SR-23 manufactured by Konishi Chemical Industry Co., Ltd. was dissolved in PGPE so as to be 20% by mass. A siloxane sol was prepared by mixing so that the sun ratio was 0.3% by mass. Subsequently, a transfer film was prepared in the same manner as in Example 1, and then a crosslinked transfer film was prepared by irradiating UV of 2,000 mJ / cm ² from the transfer layer side. To obtain a substrate with an uneven structure.

[Example 22]
Example 1 except that the mold used for thermal imprinting is a hemispherical convex shape having a diameter of 0.05 μm and a height of 0.04 μm arranged discretely in a regular triangle shape with a pitch of 0.07 μm. In the same manner as above, a support film was obtained. Further, a siloxane polymer obtained by copolymerizing KBM-13 (methyltrimethoxysilane) and KBM-403 (3-glycidoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd. at a molar ratio of 70/30, A siloxane sol was prepared by dissolving in PGPE so as to have a polymer concentration of 5% by mass, and adding CIPAG-II manufactured by Ibitsu Co., Ltd. as a photoacid generator to a siloxane polymer ratio of 0.5% by mass. Subsequently, after producing a transfer film in the same manner as in Example 1, a crosslinked transfer film was produced by irradiating UV at 750 mJ / cm ² from the transfer layer side, and transferred to the substrate in the same manner as in Example 7. Thus, a substrate with an uneven structure was obtained.

[Example 23]
The photoacid generator was CPI-110B (sulfonium photoacid generator) manufactured by San-Apro Co., Ltd., and the content was 0.6% by mass. A substrate was obtained.

[Example 24]
The photoacid generator was WPI-113 (iodonium salt photoacid generator) manufactured by Wako Pure Chemical Industries, Ltd., its content was 5.0 mass%, and the UV irradiation amount was 3,000 mJ / cm ² . Except for this, a crosslinked transfer film and a substrate with an uneven structure were obtained in the same manner as in Example 1.

[Example 25]
The photoacid generator was TFE-triazine (triazine photoacid generator) manufactured by Sanwa Chemical Co., Ltd., and its content was 5.0% by mass. A structured substrate was obtained.

[Example 26]
A siloxane sol was prepared by dissolving polymethylphenylsilsesquioxane SR-3321 manufactured by Konishi Chemical Industry Co., Ltd. in PGPE at a concentration of 20% by mass, and a photoacid generator CPI-200K (sulfonium-based light manufactured by San Apro Co., Ltd.). A cross-linked transfer film and a substrate with a concavo-convex structure were obtained in the same manner as in Example 1 except that the acid generator was added so that the solid content was 0.8% by mass relative to SR-3321.

[Example 27]
A siloxane sol was copolymerized with Shin-Etsu Chemical Co., Ltd. KBE-13 (methyltriethoxysilane), KBE-04 (tetraethoxysilane) and KBE-22 (dimethyldiethoxysilane) at a molar ratio of 65/20/15. The siloxane polymer thus obtained was made into a solution having a siloxane polymer concentration of 20% by mass with PGPE, and a photoacid generator CPI-200K (sulfonium photoacid generator) manufactured by San Apro Co., Ltd. was used with a siloxane polymer ratio of 0.8% by mass. A cross-linked transfer film and a substrate with a concavo-convex structure were obtained in the same manner as in Example 1 except that it was added so as to be prepared.

[Example 28]
The mold used for thermal imprinting is a cylindrical shape having a diameter of 230 nm and a height of 200 nm that is discretely arranged in a regular triangle shape having a pitch of 460 nm, the substrate is a silicon substrate, and the heat treatment temperature of the substrate with a concavo-convex structure A crosslinked transfer film and a substrate with a concavo-convex structure were obtained in the same manner as in Example 7 except that the temperature was 800 ° C.

[Example 29]
A crosslinked transfer film and a substrate with an uneven structure were obtained in the same manner as in Example 28 except that the substrate was a sapphire substrate and the heat treatment temperature of the substrate with an uneven structure was 1,000 ° C.

[Example 30]
A crosslinked transfer film and a substrate with an uneven structure were obtained in the same manner as in Example 1 except that the substrate was a gallium nitride substrate.

[Example 31]
A siloxane sol was prepared by dissolving polymethylsilsesquioxane SR-13 manufactured by Konishi Chemical Industry Co., Ltd. in PGPE to a concentration of 20% by mass, and a photobase generator WPBG- manufactured by Wako Pure Chemical Industries, Ltd. A substrate with a concavo-convex structure was obtained in the same manner as in Example 28 except that 266 was added so that the solid content was 0.1% by mass of the methylsiloxane polymer ratio.

[Example 32]
A siloxane sol was prepared by dissolving polyphenylsilsesquioxane SR-23 manufactured by Konishi Chemical Industry Co., Ltd. in PGPE to a concentration of 20% by mass, and a photobase generator WPBG- manufactured by Wako Pure Chemical Industries, Ltd. A substrate with a concavo-convex structure was obtained in the same manner as in Example 1 except that 300 was added so that the solid content was 0.05% by mass of the methylsiloxane polymer ratio.

[Example 33]
A support film in the same manner as in Example 1 except that the mold used for the thermal imprint was a cylindrical shape having a diameter of 6 μm and a height of 9 μm arranged discretely in a regular triangle shape with a pitch of 12 μm. Got. Further, KBM-13 (methyltrimethoxysilane), KBM-403 (3-glycidoxypropyltrimethoxysilane) and KBM-202SS (diphenyldimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd. at a molar ratio of 50/25/25 The siloxane polymer obtained by copolymerization was made into a solution having a polymer concentration of 20% by mass with PGPE, and a photobase generator EIPBG manufactured by Ibitsu Co., Ltd. was added so as to have a siloxane polymer ratio of 5.0% by mass to obtain a siloxane sol. Prepared. Subsequently, after a transfer film was obtained in the same manner as in Example 1, a crosslinked transfer film was prepared by irradiating 250 mJ / cm ² UV from the transfer layer side, and transferred to the substrate in the same manner as in Example 7. Thus, a substrate with an uneven structure was obtained.

[Example 34]
The molar ratio of KBM-13, KBM-403 and KBM-202SS was set to 70/25/5, the photobase generator EIPBG manufactured by Ibaitsu Co., Ltd. was set to 0.05% by mass, and the light irradiation amount was 750 mJ / cm. ^A substrate with a concavo-convex structure was obtained in the same manner as in Example 33 except that ² .

[Comparative Example 1]
The transfer layer was prepared in the same manner as in Example 1 except that it was prepared by applying UV curable acrylic resin “Aronix” (registered trademark) UV3701 manufactured by Toagosei Co., Ltd. to a thickness of 10 μm. Most of the transfer layer remained on the support film without being transferred to the substrate, and the partially transferred layer also had very weak adhesion to the substrate, resulting in peeling from the substrate.

[Comparative Example 2]
What was formed by thermal imprinting on one side of a 100 μm-thick “Zeonor Film” (registered trademark) model number ZF14 made by Nippon Zeon Co., Ltd., which is a cyclic polyolefin resin, was used as the support film. For the thermal imprinting, a prism-shaped nickel electroforming mold having a pitch of 5 μm and a height of 2.5 μm was used. The mold was pressed against the film for 30 seconds under the conditions of a mold temperature of 180 ° C. and a pressure of 2.0 MPa, then cooled to 100 ° C. to release the pressure, and the support film was released. The apparatus used was a 2-ton vacuum heater press model number MKP-150TV-WH manufactured by Mikado Technos.

Polymethylsilsesquioxane SR-13 manufactured by Konishi Chemical Industries, Ltd. was dissolved in PGPE at a concentration of 20% by mass to prepare a siloxane sol. The obtained siloxane sol was applied to the surface of the support film on which the irregular shape was formed using a spin coater model 1H-DX2 manufactured by Mikasa Co., Ltd., and dried at 90 ° C. for 2 minutes to obtain a transfer film. .

The transfer film was laminated on non-alkali glass EAGLE 2000 (30 mm × 30 mm, thickness 0.63 mm) manufactured by Corning Japan Co., Ltd. prepared as a substrate so that the surface of the transfer layer was in contact with the substrate. Further, a model number F200 manufactured by Kinyo Co., Ltd. was laminated as a buffer material on the support film surface of the cross-linked transfer film, and pressed for 10 seconds at a press temperature of 20 ° C. and a press pressure of 1.38 MPa in the configuration of glass substrate / transfer film / buffer material. The apparatus used was a 2-ton vacuum heater press model number MKP-150TV-WH manufactured by Mikado Technos. Thereafter, the film as a support was peeled off at room temperature to obtain a substrate with a concavo-convex structure comprising a glass substrate / transfer layer. The obtained laminate was heat-treated at 250 ° C., but the uneven shape was flattened by the heat treatment.

[Comparative Example 3]
After applying siloxane to the support film and drying, a laminate comprising a glass substrate / transfer layer was prepared in the same manner as in Comparative Example 2 except that UV was applied to the transfer layer surface of the obtained transfer film by 500 mJ / cm ^2. Obtained. The obtained laminate was heat-treated at 250 ° C., but the uneven shape was flattened by the heat treatment.

[Comparative Example 4]
After the transfer layer was transferred to the substrate in the same manner as in Comparative Example 2, UV was irradiated from the transfer layer side to 500 mJ / cm ² to obtain a substrate with an uneven structure. The obtained laminate was heat-treated at 250 ° C., but the uneven shape was flattened by the heat treatment.

[Comparative Example 5]
The siloxane sol was the same as Comparative Example 2 except that the thermal acid generator SI-100L (sulfonium thermal acid generator) manufactured by Sanshin Chemical Industry Co., Ltd. was contained at a siloxane mass ratio of 0.5% by mass. A laminate comprising a glass substrate / transfer layer was obtained. When the obtained laminate was heat-treated at 250 ° C., the uneven shape was destroyed by the heat treatment, and the height was lowered.

Tables 1 and 2 show the evaluation results of the transfer films, cross-linked transfer films, and substrates with concavo-convex structures prepared in Examples 1 to 34 and Comparative Examples 1 to 5.

1: support film 2: transfer layer 3: uneven pitch 4: width of concave / convex concave portion 5: depth of concave / convex concave portion 6: support film thickness 7: transfer layer thickness 8: remaining film thickness 9: Substrate 10: Concavity and convexity width 11: Concavity and convexity height 12: FT-IR spectrum 13 of transfer film 13: FT-IR spectrum 14 of cross-linked transfer film 14: Low-frequency peak minimum value 15 indicating siloxane bond of transfer film 15: Transfer Peak high wavenumber end minima indicating siloxane bonds in the film

Claims (7)

1. A transfer film in which a transfer layer containing a siloxane composition is laminated on a support film having a concavo-convex shape on the surface, wherein the siloxane composition contains a photoacid generator or a photobase generator.
2. The transfer film according to claim 1, wherein the photoacid generator is a sulfonium photoacid generator.
3. The transfer film according to claim 1 or 2, wherein the content of the photoacid generator in the transfer layer is 0.2 to 5.0% by mass when the entire transfer layer is 100% by mass.
4. 4. The transfer film according to claim 1, wherein the support film has a concavo-convex representative pitch of 0.01 to 50 μm and an aspect ratio of 0.01 to 3.
5. A cross-linked transfer film in which a cross-linked transfer layer containing a siloxane composition is laminated on a support film having an uneven shape, and the value of P1 / P2 described in the specification obtained from the FT-IR spectrum of the cross-linked transfer layer Is a cross-linked transfer film of 0.12 or more.
6. The cross-linked transfer film according to claim 5, wherein the support film has a concavo-convex representative pitch of 0.01 to 50 μm and an aspect ratio of 0.01 to 3.
7. A substrate with a concavo-convex structure in which a cross-linked transfer layer having a concavo-convex shape on a surface thereof containing a siloxane composition is laminated on a substrate, wherein P1 / P in the specification obtained from an FT-IR spectrum of the cross-linked transfer layer A substrate with a concavo-convex structure in which the value of P2 is 0.12 or more.

Images