WO2017195548A1 - Photocurable composition for nanoimprint and method for producing optical component - Google Patents

Abstract

Provided is a photocurable composition for nanoimprint, which has excellent fast curing properties and coating uniformity, and which is capable of exhibiting excellent shape transferability, while suppressing swelling of a silicone mold in a nanoimprint method. A photocurable composition for nanoimprint according to the present invention contains the component (A), the component (B), the component (C) and the component (D) described below, and is configured such that, relative to the total amount of curable compounds contained in the photocurable composition, the content of the component (A) is 10-60% by weight, the content of the component (B) is 10% by weight or more and the content of the component (C) is 10% by weight or more. Component (A): an alicyclic epoxy compound which has at least one partial structure represented by formula [a], while having a molecular weight of 400 or more and an SP value of Fedors of 9.0 (cal/cm³)^1/2 or more (In formula [a], R¹-R⁹ and X are as defined in the description.) Component (B): an oxetane compound which has an SP value of Fedors of 10.0 (cal/cm³)^1/2 or more or a molecular weight of 400 or more (excluding compounds that fall under the category of the component (A)) Component (C): a cationic curable compound having a number average molecular weight of 1,000 or more (excluding compounds that fall under the category of the component (A) or the component (B)) Component (D): a photopolymerization initiator

Description

Photo-curable composition for nanoimprint, and method for producing optical component

The present invention relates to a photocurable composition for nanoimprint and a method for producing an optical component using the same. This application claims the priority of Japanese Patent Application No. 2016-096087 for which it applied to Japan on May 12, 2016, and uses the content here.

A light emitting diode (LED) is excellent in energy conversion efficiency and has a long life, so that it is frequently used in electronic devices. The LED element has a structure in which a light emitting layer made of a GaN-based semiconductor is laminated on an inorganic material substrate. However, there is a large refractive index difference between the inorganic material substrate, the GaN-based semiconductor, and the atmosphere, and most of the total amount of light generated in the light-emitting layer disappears due to repeated internal reflection, resulting in poor light extraction efficiency. . For this reason, a method of improving the light extraction efficiency by forming a fine pattern of about several μm on the surface of the inorganic material substrate and laminating a light emitting layer made of a GaN-based semiconductor thereon is adopted.

As a method for forming a fine pattern, a lithography method and a nanoimprint method are known. The lithography method is expensive and the process is complicated. On the other hand, the nanoimprint method is advantageous because a fine pattern can be produced by a very simple device and process.

In the nanoimprint method, a coating film of a resist (curable composition) is formed on a substrate, a mold having a fine pattern shape is pressed on the coating film to transfer the fine pattern, and then the coating film is cured. A fine pattern can be formed on the substrate by dry etching the substrate using an object as a mask. As methods for improving dry etching resistance under high temperature conditions, Patent Documents 1 and 2 describe a method of adding a large amount of a high molecular weight component to a resist or adding an inorganic filler. Patent Document 3 describes a method including a step of filling a silicon mold having a patterned surface with a curable composition and then curing the curable composition to form a pattern shape.

JP 11-327125 A JP 2007-072374 A Special table 2008-512281 gazette

As in Patent Documents 1 and 2, when a large amount of a high molecular weight component is added, there is a problem that transferability and coatability are deteriorated. In addition, when an inorganic filler is added, a hard residue may be generated after dry etching, thereby reducing the yield. In addition, when a conventional resist is used and dry etching is performed in a high temperature environment, resist burning may occur, and the dry etching process temperature is limited by the heat resistance temperature of the resist.

In the method using a silicon mold as described in Patent Document 3, there is a problem that the silicon mold swells by sucking the resist when it comes into contact with the uncured resist (curable composition) during imprint molding. This swelling occurs remarkably at the initial use frequency (for example, 1 to 5 times) in the case of repeatedly using the silicon mold, and after that, when the saturation is reached, the swelling does not appear apparently. From the above, in the initial stage of repeated use of the silicon mold, there is a problem that the resist volume is reduced due to swelling, so that it becomes smaller than the pattern shape design. In anticipation of this, it may be possible to make the resist coating thicker than the design, but it is difficult to fine-tune the coating, resulting in excessive residual film formation or pattern shape size that is likely to be smaller than the design. The problem is that the yield (productivity) deteriorates in the initial stage of repeated use.

As a method for suppressing this swelling, for example, there is a method of introducing a fluoro functional group into the surface of a silicon mold as described in Thin Solid Films 520 (2012) 2293-2300, but due to an increase in the number of steps in the mold manufacturing process. There is a drawback of increased costs. In addition, there is a method of using a polymerizable compound having a fluoro functional group as a resist, but there is a drawback that the adhesion to the substrate is impaired.

Accordingly, an object of the present invention is to provide a photocurable composition for nanoimprinting that is excellent in rapid curing properties and coating uniformity, has excellent shape transferability in a nanoimprinting method, and can suppress swelling of a silicon mold. is there. Moreover, the objective of this invention is providing the manufacturing method of the optical component which is excellent in light extraction efficiency using the said photocurable composition for nanoimprints.

As a result of intensive studies to achieve the above object, the present inventor has found that a photocurable composition for nanoimprinting containing a specific alicyclic epoxy compound, oxetane compound, cationic curable compound, and photopolymerization initiator is a nanoimprint method. It was found that the swelling of the silicon mold can be suppressed. The present invention has been completed based on these findings.

That is, this invention contains the following component (A), component (B), component (C), and component (D), and said component (A) with respect to the curable compound whole quantity contained in a photocurable composition. ) Is 10 to 60% by weight, the component (B) is 10% by weight or more, and the component (C) is 10% by weight or more. A curable composition is provided.
Component (A): Fat having at least one partial structure represented by the following formula [a], a molecular weight of 400 or more, and a Fedors SP value of 9.0 (cal / cm ³ ) ^1/2 or more Cyclic epoxy compounds

[Wherein, R ¹ to R ⁹ are the same or different and each represents a hydrogen atom, a halogen atom, an oxygen atom, a hydrocarbon group that may contain a halogen atom, or an alkoxy group that may have a substituent. . X represents an ester bond, an ether bond, a carbonyl group, a carbonate group, an alkylene group, an alkenylene group, or a combination of these bonds or groups]
Component (B): Oxetane compound having an SP value of Fedors of 10.0 (cal / cm ³ ) ^1/2 or more, or a molecular weight of 400 or more (excluding compounds corresponding to component (A))
Component (C): a cationic curable compound having a number average molecular weight of 1000 or more (excluding compounds corresponding to component (A) and component (B))
Component (D): Photopolymerization initiator

The present invention also provides the above-described photocurable composition for nanoimprints, which contains a surface modifier.

Also, the present invention provides the above-mentioned photocurable composition for nanoimprints containing a solvent.

Further, the present invention provides the nanoimprinting composition, wherein the content of the component (D) is 0.05 to 10 parts by weight with respect to the total amount (100 parts by weight) of the curable compound contained in the photocurable composition. A photocurable composition is provided.

The present invention also provides a method for producing an optical component comprising a step of applying the above-described photocurable composition for nanoimprint on a substrate, and a step of bringing the applied coating film into contact with a silicon mold and photocuring.

The present invention also provides the method for producing the optical component, wherein the silicon mold material is polydimethylsiloxane.

The present invention also provides the method for producing the optical component, wherein the light source used for the photocuring is a UV-LED (wavelength: 350 to 400 nm).

Also, the present invention provides a method for manufacturing the optical component further including an etching step.

That is, the present invention relates to the following.
[1] Containing the component (A) with respect to the total amount of the curable compound contained in the photocurable composition, including the following component (A), component (B), component (C), and component (D) The photocurable composition for nanoimprint, wherein the amount is 10 to 60% by weight, the content of the component (B) is 10% by weight or more, and the content of the component (C) is 10% by weight or more. object.
Component (A): an alicyclic ring having at least one partial structure represented by the formula [a], having a molecular weight of 400 or more and a Fedors SP value of 9.0 (cal / cm ³ ) ^1/2 or more Formula epoxy compound component (B): Oxetane compound having SP value of Fedors of 10.0 (cal / cm ³ ) ^1/2 or higher, or molecular weight of 400 or higher (excluding compounds corresponding to component (A))
Component (C): a cationic curable compound having a number average molecular weight of 1000 or more (excluding compounds corresponding to component (A) and component (B))
Component (D): Photocurable initiator [2] The photocurable composition for nanoimprints according to [1], which comprises a surface modifier.
[3] The photocurable composition for nanoimprints according to [1] or [2], which contains a solvent.
[4] The content of the component (D) is 0.05 to 10 parts by weight with respect to the total amount (100 parts by weight) of the curable compound contained in the photocurable composition [1] to [3] The photocurable composition for nanoimprints according to any one of the above.
[5] The nanoimprint light according to any one of [1] to [4], wherein in the component (A), R ¹ to R ⁹ in the partial structure represented by the formula [a] are all hydrogen atoms Curable composition.
[6] The photocurable composition for nanoimprints according to any one of [1] to [5], wherein the component (A) has 2 to 10 partial structures represented by the formula [a].
[7] The photocurable composition for nanoimprints according to any one of [1] to [6], wherein the component (A) is a compound having at least one partial structure represented by the formula [a ′] .
[8] The photocurable composition for nanoimprints according to any one of [1] to [7], wherein the component (A) is a compound represented by formulas (a-1) to (a-3) .
[9] The photocurable composition for nanoimprints according to any one of [1] to [8], wherein the component (B) is a compound represented by the formula (b).
[10] The photocurable property for nanoimprints according to any one of [1] to [9], wherein the component (B) is a compound represented by the formula (b-1) or the formula (b-2) Composition.
[11] The photocurable composition for nanoimprints according to any one of [1] to [10], wherein the component (C) is an epoxy compound.
[12] The component (C) according to any one of [1] to [11], wherein the component (C) is a glycidyl ether type epoxy compound, a glycidyl amine type epoxy compound, a glycidyl ester type epoxy compound, or an olefin oxidation type epoxy compound. A photocurable composition for nanoimprint.
[13] The SP value of the component (C) at 25 ° C. according to the method of Fedors is 9.2 to 15 (cal / cm ³ ) ^1/2 [1] to [12] A photocurable composition for nanoimprint.
[14] The total content of component (A), component (B) and component (C) is 70% by weight or more based on the total amount (100% by weight) of the curable compound contained in the photocurable composition. The photocurable composition for nanoimprints according to any one of [1] to [13].
[15] The nanoimprint according to any one of [1] to [14], wherein the photopolymerization initiator as component (D) is a photocationic polymerization initiator, a photoanionic polymerization initiator, or a radical polymerization initiator. Photocurable composition.
[16] The photocationic polymerization initiator is a diazonium salt compound, an iodonium salt compound, a sulfonium salt compound, a phosphonium salt compound, a selenium salt compound, an oxonium salt compound, an ammonium salt compound, or a bromine salt compound. The photocurable composition for nanoimprints according to [15], which is a compound.
[17] The photocurable composition for nanoimprints according to any one of [1] to [16], comprising the following component (E):
Component (E): Compound [18] with a SP value of Fedors of 11.5 (cal / cm ³ ) ^1/2 or more The boiling point (at 760 mmHg) of component (E) is more than 160 to 300 ° C. [17 ] The photocurable composition for nanoimprints of description.
[19] The photocurable composition for nanoimprints according to [17] or [18], wherein the component (E) is an alcohol compound.
[20] The content of component (E) is 0.1 to 20 parts by weight with respect to the total amount (100 parts by weight) of the curable compound contained in the photocurable composition. The photocurable composition for nanoimprints according to any one of the above.
[21] A step of applying the photocurable composition for nanoimprinting according to any one of [1] to [20] onto a substrate, and a step of bringing the applied coating film into contact with a silicon mold and performing photocuring. A method for manufacturing an optical component.
[22] The method for manufacturing an optical component according to [21], wherein the raw material of the silicon mold is polydimethylsiloxane.
[23] The method for manufacturing an optical component according to [21] or [22], wherein the light source used for the photocuring is a UV-LED (wavelength: 350 to 400 nm).
[24] The method for manufacturing an optical component according to any one of [21] to [23], further including an etching step.

Since the photocurable composition for nanoimprinting of the present invention has the above-described configuration, resist burning is unlikely to occur, the temperature in the etching process is not limited, fast curability, excellent coating uniformity, and in the nanoimprinting method, It is excellent in shape transferability, can suppress swelling of the silicon mold, and is excellent in workability of imprint molding. Further, the method for producing an optical component of the present invention can produce an optical component with good productivity and excellent light extraction efficiency.

[Photocurable composition for nanoimprint]
The photocurable composition for nanoimprint of the present invention (hereinafter sometimes referred to as “the present invention” or “photocurable composition”) includes the following component (A), component (B), component (C), And the component (D), the content of the component (A) is 10 to 60% by weight with respect to the total amount of the curable compound contained in the photocurable composition, and the content of the component (B) Is 10% by weight or more, and the content of the component (C) is 10% by weight or more.
Component (A): has at least one partial structure represented by the following formula [a], has a (number average) molecular weight of 400 or more, and a Fedors SP value of 9.0 (cal / cm ³ ) ^1/2 An alicyclic epoxy compound

[Wherein, R ¹ to R ⁹ are the same or different and each represents a hydrogen atom, a halogen atom, an oxygen atom, a hydrocarbon group that may contain a halogen atom, or an alkoxy group that may have a substituent. . X represents an ester bond, an ether bond, a carbonyl group, a carbonate group, an alkylene group, an alkenylene group, or a combination of these bonds or groups]
Component (B): Oxetane compound having an SP value of Fedors of 10.0 (cal / cm ³ ) ^1/2 or more, or (number average) molecular weight of 400 or more (excluding compounds corresponding to component (A))
Component (C): a cationic curable compound having a number average molecular weight of 1000 or more (excluding compounds corresponding to component (A) and component (B))
Component (D): Photopolymerization initiator

[Component (A)]
The component (A) in the present invention has at least one partial structure represented by the formula [a], has a (number average) molecular weight of 400 or more, and a Fedors SP value of 9.0 (cal / cm ^3). ) 1 type or 2 types or more of alicyclic epoxy compounds which are ^1/2 or more. In the present invention, by including the component (A), the photocationic curability can be enhanced while suppressing the swelling of the silicon mold by the photocurable composition.

Examples of the halogen atom in R ¹ to R ⁹ in the formula [a] include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

Examples of the hydrocarbon group in R ¹ to R ⁹ of the formula [a] include an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group in which two or more of these are bonded. it can.

Examples of the aliphatic hydrocarbon group include alkyl groups having 1 to 20 carbon atoms (= C _1-20 ) such as methyl, ethyl, propyl, isopropyl, butyl, hexyl, octyl, isooctyl, decyl and dodecyl groups (preferably C _1-10 alkyl group, particularly preferably C _1-4 alkyl group); vinyl, allyl, methallyl, 1-propenyl, isopropenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl C _2-20 alkenyl groups such as 3-pentenyl, 4-pentenyl, 5-hexenyl groups (preferably C _2-10 alkenyl groups, particularly preferably C _2-4 alkenyl groups); C ₂ such as ethynyl, propynyl groups, etc. _-20 alkynyl group (preferably a C _2-10 alkynyl group, particularly preferably a C _2-4 alkynyl group).

Examples of the alicyclic hydrocarbon group include C _3-12 cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cyclododecyl groups; C _3-12 cycloalkenyl groups such as cyclohexenyl groups; and bicycloheptanyl. And a C _4-15 bridged cyclic hydrocarbon group such as a bicycloheptenyl group.

Examples of the aromatic hydrocarbon group include C _6-14 aryl groups (preferably C _6-10 aryl groups) such as phenyl and naphthyl groups.

As the hydrocarbon group optionally containing an oxygen atom or a halogen atom in R ¹ to R ⁹ of the formula [a], at least one hydrogen atom in the above-mentioned hydrocarbon group is a group having an oxygen atom or a halogen atom. And a group substituted with a group. Examples of the group having an oxygen atom include hydroxyl group; hydroperoxy group; C _1-10 alkoxy group such as methoxy, ethoxy, propoxy, isopropyloxy, butoxy, isobutyloxy group; C _2-10 such as allyloxy group. An alkenyloxy group; a C _6-14 allyloxy group optionally having a substituent selected from a C _1-10 alkyl group, a C _2-10 alkenyl group, a halogen atom, and a C _1-10 alkoxy group (for example, Tolyloxy, naphthyloxy groups, etc.); C _7-18 aralkyloxy groups such as benzyloxy, phenethyloxy groups; C _1-10 acyloxy groups such as acetyloxy, propionyloxy, (meth) acryloyloxy, benzoyloxy groups; methoxycarbonyl , ethoxycarbonyl, propoxycarbonyl, C _1-10 alkoxy, such as butoxycarbonyl group Aryloxycarbonyl group; C _1-10 alkyl group, C _2-10 alkenyl group, a halogen atom, and C _1-10 may have a substituent group selected from alkoxy C _6-14 allyloxycarbonyl group ( For example, phenoxycarbonyl, tolyloxycarbonyl, naphthyloxycarbonyl group, etc.); C _7-18 aralkyloxycarbonyl group such as benzyloxycarbonyl group; epoxy group-containing group such as glycidyloxy group; oxetanyl group such as ethyloxetanyloxy group Groups: C _1-10 acyl groups such as acetyl, propionyl and benzoyl groups; isocyanate groups; sulfo groups; carbamoyl groups; oxo groups; and two or more of these are bonded via a single bond or a C _1-10 alkylene group And the like. Examples of the group having a halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

Examples of the alkoxy group represented by R ¹ to R ⁹ in the formula [a] include C _1-10 alkoxy groups such as methoxy, ethoxy, propoxy, isopropyloxy, butoxy, and isobutyloxy groups.

Examples of the substituent in the alkoxy group which may have the above substituent include a halogen atom, a hydroxyl group, a C _1-10 alkoxy group, a C _2-10 alkenyloxy group, a C _6-14 allyloxy group, and C _1-10 acyloxy group, mercapto group, C _1-10 alkylthio group, C _2-10 alkenylthio group, C _6-14 allylthio group, C _7-18 aralkylthio group, carboxyl group, C _1-10 alkoxycarbonyl group, C _6-14 allyloxycarbonyl group, C _7-18 aralkyloxycarbonyl group, amino group, mono or di C _1-10 alkylamino group, C _1-10 acylamino group, epoxy group-containing group, oxetanyl group-containing group, C Examples thereof include a _1-10 acyl group, an oxo group, and a group in which two or more of these are bonded through a single bond or a C _1-10 alkylene group.

As R ¹ to R ^{9 in} the formula [a], a hydrogen atom is particularly preferable.

X in the formula [a] represents an ester bond (—COO—), an ether bond (—O—), a carbonyl group (—CO—), a carbonate group (—O—CO—O—), an alkylene group, an alkenylene group, Alternatively, a plurality of these bonds or groups are linked.

Examples of the alkylene group include a C _1-20 alkylene group, preferably a C _1-10 alkylene group, more preferably a C _1-8 alkylene group, and particularly preferably a methylene group, an ethylene group, and propylene. Group, butylene group, pentylene group and hexylene group.

Examples of the alkenylene group include a C _1-20 alkenylene group, preferably a C _1-10 alkenylene group, more preferably a C _1-8 alkenylene group, and particularly preferably an ethylene group, a propylene group, and a butene group. Group, pentene group and hexylene group.

Component (A) has at least one partial structure represented by the above formula [a], but preferably has 2 to 10 such partial structures from the viewpoint of excellent cationic curability. 3 to 8 are more preferable, and 4 to 6 partial structures are more preferable. In addition, when it has the partial structure represented by two or more Formula [a], several X couple | bonds and it comprises 1 molecule. When it has a partial structure represented by two or more formulas [a], a plurality of X may be the same or different.

Examples of the compound having at least one partial structure represented by the formula [a] include a compound having at least one partial structure represented by the following formula [a ′].

[Wherein Y represents an ester bond, an ether bond, a carbonyl group, a carbonate group, an alkylene group, an alkenylene group, or a combination of these bonds or groups]

As the alkylene group and alkenylene group in Y of the formula [a ′], the same groups as those mentioned for X can be mentioned. The compound having at least one partial structure represented by the above formula [a ′] preferably has 2 to 10 partial structures from the viewpoint of excellent cationic curability, and the partial structures have 3 to 8 More preferably, it has 4 to 6 partial structures. In addition, when it has the partial structure represented by two or more formula [a '], several Y couple | bonds and it comprises 1 molecule. In the case of having two or more partial structures represented by the formula [a ′], the plurality of Y may be the same or different.

Component (A) is particularly preferably an alicyclic epoxy compound containing a cyclohexene oxide group and having a (poly) ester structure, for example, a structure in which a lactone is opened or a repeating unit thereof.

Component (A) has a (number average) molecular weight of 400 or more (for example, 400 to 3000), preferably 450 to 1500, more preferably 500 to 1200, and further preferably 550 to 1000. Since the molecular weight of a component (A) is the said range, swelling of the silicon mold by a curable composition can be suppressed. On the other hand, if the molecular weight exceeds the above range, the viscosity is too high and the moldability during imprinting may be affected. In addition, (number average) molecular weight means that it is a number average molecular weight when the component (A) is a polymer.

The SP value (solubility parameter) at 25 ° C. of the component (A) by the Fedors method [see Polym. Eng. Sci., 14, 147 (1974)] is 9.0 or more (for example, 9.0 to 13.0). ), Preferably 9.5 or more, more preferably 10.0 or more, and even more preferably 10.5 or more. Since the SP value of the component (A) is in the above range, the SP value with silicone is greatly different, so that the swelling of the silicon mold with the curable composition can be suppressed. The unit of the SP value is (cal / cm ³ ) ^1/2 .

Typical examples of the alicyclic epoxy compounds having molecular weights and SP values in the above ranges include compounds represented by the following formulas (a-1) to (a-3). Of these, compounds represented by the following formula (a-1) are preferred. As a commercial product of such an alicyclic epoxy compound, a trade name “Epolide GT401” (manufactured by Daicel Corporation) or the like can be used.

[L, m, n, and o in the formula are 0 or an integer of 1 or more, and l + m + n + o is 1 or more. p and q are integers of 0 to 10, and p + q ≧ 1. r is an integer from 2 to 10]

The content of component (A) (when two or more types are contained, the total amount thereof) is 10 to 60% by weight, preferably 15 to 55% by weight, based on the total amount of the curable compound contained in the photocurable composition. %, More preferably 20 to 50% by weight, still more preferably 30 to 45% by weight. Since content of a component (A) is the said range, the photocationic sclerosis | hardenability of a photocurable composition is improved, it is easy to obtain the hardened | cured material which was excellent in quick curability and was excellent in etching resistance, and depends on a curable composition. Swelling of the silicon mold can be suppressed. The curable compound includes component (A), component (B), component (C), and other curable compounds that are optional components.

[Component (B)]
As the component (B) in the present invention, an oxetane compound having an SP value (solubility parameter) at 25 ° C. of 10.0 (cal / cm ³ ) ^1/2 or more or a (number average) molecular weight of 400 or more according to the method of Fedors 1 type or 2 types or more are included (except the compound applicable to a component (A)). In the present invention, by including the component (B), the polymerization rate can be increased while making the photocurable composition highly polar and low swellable. The component (B) may be an oxetane compound having an SP value of 10.0 (cal / cm ³ ) ^1/2 or more, or an oxetane compound having a molecular weight of 400 or more. cal / cm ³ ) ^1/2 or more, and an oxetane compound having a molecular weight of 400 or more may be used.

The component (B) is represented by the following formula (b), for example.

[Wherein, R ^e represents a monovalent organic group, and R ^f represents a hydrogen atom or an ethyl group. t represents an integer of 0 or more]

The monovalent organic group in R ^e of the formula (b) includes a monovalent hydrocarbon group, a monovalent heterocyclic group, a substituted oxycarbonyl group (alkoxycarbonyl group, allyloxycarbonyl group, aralkyloxycarbonyl group, cyclo Alkyloxycarbonyl group etc.), substituted carbamoyl group (N-alkylcarbamoyl group, N-allylcarbamoyl group etc.), acyl group (aliphatic acyl group such as acetyl group; aromatic acyl group such as benzoyl group), and the like A monovalent group in which two or more of these are bonded via a single bond or a linking group is included.

Examples of the monovalent hydrocarbon group of the formula (b) include the same examples as R ¹ to R ^{9 in} the formula [a].

The monovalent hydrocarbon group of the formula (b) has various substituents [for example, halogen atom, oxo group, hydroxyl group, substituted oxy group (alkoxy group, allyloxy group, aralkyloxy group, acyloxy group, etc.), carboxyl group Substituted oxycarbonyl group (alkoxycarbonyl group, allyloxycarbonyl group, aralkyloxycarbonyl group, etc.), substituted or unsubstituted carbamoyl group, cyano group, nitro group, substituted or unsubstituted amino group, sulfo group, heterocyclic group, etc. ] May be included. The hydroxyl group and carboxyl group may be protected with a protective group commonly used in the field of organic synthesis.

The heterocyclic ring constituting the heterocyclic group includes an aromatic heterocyclic ring and a non-aromatic heterocyclic ring. For example, a heterocyclic ring containing an oxygen atom as a hetero atom (for example, a 4-membered ring such as an oxetane ring; 5-membered ring such as furan ring, tetrahydrofuran ring, oxazole ring, isoxazole ring, γ-butyrolactone ring; 6-membered ring such as 4-oxo-4H-pyran ring, tetrahydropyran ring, morpholine ring; benzofuran ring, isobenzofuran ring , 4-oxo-4H-chromene ring, chroman ring, isochroman ring and the like; 3-oxatricyclo [4.3.1.1 ^4,8 ] undecan-2-one ring, 3-oxatricyclo [ 4.2.1.0 ^{4, 8]} nonane-2-one ring, such as cross-linked ring), heterocyclic (e.g. containing a sulfur atom as a hetero atom, a thiophene ring, a thiazole ring, an isothiazole ring, thia A 5-membered ring such as an azole ring; a 6-membered ring such as a 4-oxo-4H-thiopyran ring; a condensed ring such as a benzothiophene ring], or a heterocycle containing a nitrogen atom as a heteroatom (for example, a pyrrole ring, a pyrrolidine ring, 5-membered rings such as pyrazole ring, imidazole ring, triazole ring; 6-membered rings such as pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, piperidine ring, piperazine ring; indole ring, indoline ring, quinoline ring, acridine ring, naphthyridine Ring, quinazoline ring, condensed ring such as purine ring, etc.). Examples of the monovalent heterocyclic group include groups in which one hydrogen atom has been removed from the above structural formula of the heterocyclic ring.

In addition to the substituent that the hydrocarbon group may have, the heterocyclic group may be an alkyl group (eg, a C _1-4 alkyl group such as a methyl group or an ethyl group), C _3-12 cycloalkyl, and the like. Group and a substituent such as C _6-14 aryl group (for example, phenyl group, naphthyl group, etc.).

Examples of the linking group include a carbonyl group (—CO—), an ether bond (—O—), a thioether bond (—S—), an ester bond (—COO—), an amide bond (—CONH—), and a carbonate bond. (—OCOO—), silyl bond (—Si—), and those in which a plurality of these are linked.

T represents an integer of 0 or more, and is, for example, 0 to 12, preferably 1 to 6.

Examples of the compound represented by the above formula (b) include compounds represented by the following formula (b-1) and formula (b-2).

Commercially available products of the compound represented by the above formula (b) include, for example, trade name “Aron Oxetane OXT-101” (manufactured by Toagosei Co., Ltd.), trade name “ETERRNACOLL OXBP” (produced by Ube Industries) Etc. can be used.

The (number average) molecular weight of component (B) is, for example, 100 or more (for example, 100 to 3000), preferably 200 to 1500, more preferably 300 to 1300, and further preferably 400 to 1200. is there. Since the molecular weight of a component (B) is the said range, the swelling of the silicon mold by a curable composition can be suppressed. In addition, (number average) molecular weight means that it is a number average molecular weight when component (B) is a polymer. The component (B) may have a molecular weight of less than 400 when the SP value is 10.0 or more.

The SP value (solubility parameter) at 25 ° C. of the component (B) by the Fedors method [see Polym. Eng. Sci., 14, 147 (1974)] is, for example, 10.0 or more (for example, 10.0 to 15). 0.0), preferably 10.1 or more, more preferably 10.2 or more, and still more preferably 10.3 or more. When the SP value of the component (B) is in the above range, the SP value with silicone is greatly different, so that the swelling of the silicon mold by the photocurable composition can be suppressed. The unit of SP value is (cal / cm ³ ) ^1/2 . When the molecular weight is 400 or more, the component (B) may have an SP value of less than 10.0.

Component (B) preferably has an SP value of 10.0 or more and a molecular weight of 100 or more, more preferably an SP value of 10.0 or more and a molecular weight of 200 or more, and an SP value of 10. More preferably, the molecular weight is 0 or more and 300 or more. The component (B) preferably has a molecular weight of 400 or more and an SP value of 9.0 or more, more preferably a molecular weight of 400 or more and an SP value of 9.3 or more, and a molecular weight of 400. More preferably, the SP value is 9.5 or more. The unit of SP value is (cal / cm ³ ) ^1/2 .

The content of component (B) (when 2 or more types are contained, the total amount) is 10% by weight or more (for example, 10 to 80% by weight) with respect to the total amount of the curable compound contained in the photocurable composition. Yes, preferably 15 to 60% by weight, more preferably 18 to 55% by weight, and still more preferably 20 to 50% by weight. Since the content of the component (B) is in the above range, the photocurable composition has high polarity and low swellability, can suppress swelling of the silicon mold, and can increase the polymerization rate. The curable compound includes component (A), component (B), component (C), and other curable compounds that are optional components.

[Component (C)]
As the component (C) in the present invention, a cationic curable compound having a number average molecular weight (M _n ; standard polystyrene conversion by GPC) of 1000 or more (excluding compounds corresponding to the component (A) and the component (B)). Contains one or more. The component (C) is a compound other than the components (A) and (B), and may be a resin such as a polymer or an oligomer. In the present invention, by including the component (C) which is a high molecular weight compound, when the coating film is formed by the spin coating method, the phenomenon that the edge thickness of the coating film becomes thick (edge beat phenomenon) is effectively suppressed. can do.

The component (C) is a compound containing one or more cationic curable groups (preferably two or more, more preferably four or more). Examples of the cationic curable group include an epoxy group, an oxetanyl group, a glycidyl ether group, a vinyl ether group, and a hydroxyl group. Of these, an epoxy group, an oxetanyl group, and a glycidyl ether group are preferable, and a glycidyl ether group is particularly preferable. That is, an epoxy compound is preferable as the component (C).

Examples of the epoxy compound include a glycidyl ether type epoxy compound, a glycidyl amine type epoxy compound, a glycidyl ester type epoxy compound, and an olefin oxidation type epoxy compound. These can be used alone or in combination of two or more.

Examples of the glycidyl ether type epoxy compound include aromatic glycidyl ether type epoxy compounds, alicyclic glycidyl ether type epoxy compounds, and aliphatic glycidyl ether type epoxy compounds.

Examples of the aromatic glycidyl ether type epoxy compound include bisphenol A type diglycidyl ether, bisphenol F type diglycidyl ether, and novolak type epoxy compounds. Examples of the bisphenol A type diglycidyl ether include bisphenol A bis (propylene glycol glycidyl ether) ether and bisphenol A bis (triethylene glycol glycidyl ether) ether. Examples of novolak type epoxy compounds include phenol novolac type epoxy resins and cresol novolak type epoxy resins. Commercially available products of aromatic glycidyl ether type epoxy compounds include “NC-3000”, “NC-3000-L”, “NC-3000-H”, “NC-3100”, “NC-2000-L”. , “EPPN-502H”, “EPPN-503” (manufactured by Nippon Kayaku Co., Ltd.), trade names “EPICLON N-890”, “EPICLON N-865” (manufactured by DIC Corporation), etc. Can be used.

Examples of the alicyclic glycidyl ether type epoxy compound include hydrogenated bisphenol A type diglycidyl ether, hydrogenated bisphenol F type diglycidyl ether, and novolac type epoxy compounds (for example, dicyclopentadiene / phenol copolymer novolac type epoxy resin, dioxygen diester) And cyclopentadiene / naphthol copolymer novolac type epoxy resin).

Examples of the aliphatic glycidyl ether type epoxy compound include a cyclic aliphatic type epoxy compound and a long chain aliphatic type epoxy compound.

Examples of the glycidylamine type epoxy compound include epoxy compounds obtained by glycidylation of amines such as aminophenol type epoxy compounds.

Examples of the glycidyl ester type epoxy compound include compounds obtained by reaction of carboxylic acid such as phthalic acid glycidyl ester type epoxy compound with epichlorohydrin.

Examples of the olefin oxide epoxy compound include compounds in which a part of the double bond of a molecular chain having a polybutadiene skeleton or a polyisoprene skeleton is epoxidized. As a commercial product of an olefin oxidation type epoxy compound, for example, trade names “Epolide PB3600”, “Epolide PB4700” (manufactured by Daicel Corporation), “Poly ip” (made by Idemitsu Kosan Co., Ltd.), etc. be able to.

Examples of the compound having a vinyl ether group (vinyl ether compound) include polyethylene glycol (meth) acrylate and methoxypolyethylene glycol (meth) acrylate.

Examples of the compound having a hydroxyl group include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol (PEG 600), propylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol, polypropylene glycol (PPG), Examples include multimers such as glycerol, diglycerol, tetraglycerol, polyglycerol, and trimethylolpropane, multimers such as pentaerythritol, polysaccharides such as glucose, fructose, lactose, and maltose.

The number average molecular weight of component (C) (M _n ; standard polystyrene conversion by GPC) is 1000 or more (for example, 1000 to 100,000), preferably 1200 or more, more preferably 1500 or more, and further preferably 1800 or more. It is. When the number average molecular weight of the component (C) is in the above range, swelling of the silicon mold by the photocurable composition can be suppressed.

The SP value (solubility parameter) of the component (C) at 25 ° C. (see Polym. Eng. Sci., 14, 147 (1974)) at 25 ° C. is, for example, 9.2 to 15, preferably 9. 3 to 13, more preferably 9.5 to 12. When the SP value of the component (C) is in the above range, the SP value with silicone is greatly different, so that swelling of the mold by the photocurable composition can be suppressed. The unit of the SP value is (cal / cm ³ ) ^1/2 .

The content of component (C) (when two or more types are contained, the total amount) is 10% by weight or more (for example, 10 to 10%) with respect to the total amount (100% by weight) of the curable compound contained in the photocurable composition. 70% by weight), preferably 15 to 60% by weight, more preferably 18 to 50% by weight, and still more preferably 20 to 45% by weight. Since content of a component (C) is the said range, it is excellent in the coating stability of a photocurable composition, and the film thickness uniformity of a coating film. The curable compound includes component (A), component (B), component (C), and other curable compounds that are optional components.

The total content of component (A), component (B), and component (C) is, for example, 70% by weight or more with respect to the total amount (100% by weight) of the curable compound contained in the photocurable composition. The amount is preferably 80% by weight or more, more preferably 90% by weight or more, still more preferably 95% by weight or more, and particularly preferably 100% by weight.

[Other curable compounds]
In the present invention, other curable compounds other than the components (A) to (C) may be used as necessary as long as the effects of the present invention are not impaired. Examples of other curable compounds include alicyclic epoxy compounds other than component (A), oxetane compounds other than component (B), vinyl ether compounds having a number average molecular weight of less than 1000, acrylic compounds, and silicone compounds. it can. The content of the other curable compound is, for example, 30% by weight or less, preferably 20% by weight or less, more preferably 10% by weight with respect to the total amount (100% by weight) of the curable compound contained in the photocurable composition. % Or less, more preferably 5% by weight or less, and particularly preferably 0% by weight. If the content of other curable compounds exceeds the above range, the effects of the present invention tend to be difficult to obtain.

[Component (D)]
As a component (D) in this invention, 1 type, or 2 or more types of photoinitiators are included. As the photopolymerization initiator, known or commonly used photocationic polymerization initiators, photoanionic polymerization initiators, radical polymerization initiators, and other substances capable of causing cationic polymerization or anionic polymerization can be used. Among these, as the component (D), a photocationic polymerization initiator is preferable.

Examples of the photocationic polymerization initiator include diazonium salt compounds, iodonium salt compounds, sulfonium salt compounds, phosphonium salt compounds, selenium salt compounds, oxonium salt compounds, ammonium salt compounds, bromine salt compounds. Etc. These can be used alone or in combination of two or more.

Among them, it is preferable to use a sulfonium salt compound as a photocationic polymerization initiator because a cured product having excellent curability can be formed. Examples of the cation moiety of the sulfonium salt compound include [4- (4-biphenylylthio) phenyl] -4-biphenylylphenylsulfonium, (4-hydroxyphenyl) methylbenzylsulfonium ion, triphenylsulfonium ion, diphenyl [ And arylsulfonium ions (particularly, triarylsulfonium ions) such as 4- (phenylthio) phenyl] sulfonium ion and tri-p-tolylsulfonium ion.

Examples of the anionic part of the cationic photopolymerization initiator include BF ₄ ⁻ , [(C ₆ H ₅ ) _s B (C ₆ F ₅ ) _{4 −s} ] ⁻ (s: integer of 0 to 3), PF ₆ ⁻ , [(Rf) _t PF _6-t ] ⁻ (Rf: an alkyl group in which 80% or more of hydrogen atoms are substituted with fluorine atoms, t: an integer of 1 to 5), AsF ₆ ⁻ , SbF ₆ ⁻ , SbF ₅ (OH) 2- ^{and the} like.

Examples of the photocationic polymerization initiator include [4- (4-biphenylylthio) phenyl] -4-biphenylylphenylsulfonium tris (pentafluoroethyl) trifluorophosphate, (4-hydroxyphenyl) methylbenzylsulfonium tetrakis ( Pentafluorophenyl) borate, 4- (4-biphenylylthio) phenyl-4-biphenylylphenylsulfonium tetrakis (pentafluorophenyl) borate, diphenyl [4- (phenylthio) phenyl] sulfonium tris (pentafluoroethyl) trifluorophosphate Diphenyl [4- (phenylthio) phenyl] sulfonium tetrakis (pentafluorophenyl) borate, diphenyl [4- (phenylthio) phenyl] sulfonium Xafluorophosphate, [4- (4-biphenylthio) phenyl] -4-biphenylphenylsulfonium tris (pentafluoroethyl) trifluorophosphate, 4- (phenylthio) phenyldiphenylsulfonium phenyltris (pentafluorophenyl) borate, etc. be able to. Commercially available photocationic polymerization initiators include trade names “Syracure UVI-6970”, “Syracure UVI-6974”, “Syracure UVI-6990”, “Syracure UVI-950” (manufactured by Union Carbide, USA), “Irgacure 250”, “Irgacure 261”, “Irgacure 264” (manufactured by BASF), “CG-24-61” (manufactured by Ciba Japan), “SP-150”, “SP-151”, “ “SP-170”, “Optomer SP-171” (manufactured by ADEKA Corporation), “DAICAT II” (manufactured by Daicel Corporation), “UVAC1590”, “UVAC1591” (manufactured by Daicel Cytec Corporation) ), “CI-2064”, “CI-2639”, “CI-2624”, “CI-2481”, “CI-2734”, “CI-2855”, “CI-2823”, “CI-2758”, “CIT-1682” (manufactured by Nippon Soda Co., Ltd.), “PI-2074” (manufactured by Rhodia, Tetrakis) (Pentafluorophenyl) borate toluylcumyl iodonium salt), “FFC509” (manufactured by 3M), “BBI-102”, “BBI-101”, “BBI-103”, “MPI-103”, “TPS-103” ”,“ MDS-103 ”,“ DTS-103 ”,“ NAT-103 ”,“ NDS-103 ”(from Midori Chemical Co., Ltd.),“ CD-1010 ”,“ CD-1011 ”,“ CD −1012 ”(above, manufactured by Sartomer, USA),“ CPI-100P ”,“ CPI-101A ”(above, manufactured by San Apro Co., Ltd.) and the like can be used.

The content of component (D) (when two or more are contained, the total amount thereof) is, for example, 0.05 to 10 parts by weight with respect to the total amount (100 parts by weight) of the curable compound contained in the photocurable composition. Preferably 0.1 to 5 parts by weight, more preferably 0.1 to 3 parts by weight. When the content of the component (D) is in the above range, the photocurable composition is excellent in rapid curability and thin film curability. The curable compound includes all of the component (A), the component (B), the component (C), and other curable compounds that are optional components.

[Component (E)]
The present invention may further include one or more of the following components (E) as optional components. Component (E) can be added as appropriate when, for example, adjusting the photocurable composition to a viscosity suitable for application to a substrate, or adjusting the polarity of the photocurable composition.
Component (E): Compound having an SP value of Fedors of 11.5 (cal / cm ³ ) ^1/2 or more

The boiling point (at 760 mmHg) of component (E) is, for example, more than 160 to 300 ° C., preferably 170 to 280 ° C., more preferably 180 to 260 ° C. That is, the component (E) is particularly preferably a compound having a Fedors SP value of 11.5 (cal / cm ³ ) ^1/2 or more and a boiling point of over 160 ° C. When two or more components (E) are included, the proportion of the solvent having a boiling point of more than 160 ° C. is, for example, 70% by weight or more, preferably 80% by weight with respect to the total amount (100% by weight) of component (E) % Or more, more preferably 90% by weight or more, and still more preferably 100% by weight.

The SP value (solubility parameter) at 25 ° C. of the component (E) by the Fedors method [see Polym. Eng. Sci., 14, 147 (1974)] is, for example, 11.5 or more (for example, 11.5 to 18 0.0), preferably 12.0 or more, more preferably 13.0 or more. When the SP value of the component (C) is in the above range, the polarity of the photocurable composition can be increased even with a small addition amount. The unit of the SP value is (cal / cm ³ ) ^1/2 .

Component (E) is a compound other than the curable compound, is a liquid at room temperature, and preferably has a lower viscosity than the curable compound, and particularly preferably an alcohol compound. Examples of alcohol compounds include monohydric alcohols such as 1-heptanol and 1-octanol, dihydric alcohols such as ethylene glycol and diethylene glycol, trihydric alcohols such as glycerin, 1,4-cyclohexanedimethanol, 1,1-cyclohexanediethanol, and the like. (Polyhydric) alcohol containing an alicyclic ring. Of these, polyhydric alcohols having a plurality of hydroxyl groups in one molecule (for example, dihydric or trihydric alcohols) are preferable.

The content when the component (E) is included is, for example, 0.1 to 20 parts by weight, preferably 1 to 10 parts by weight with respect to the total amount (100 parts by weight) of the curable compound contained in the photocurable composition. Parts by weight, more preferably 2 to 8 parts by weight. The curable compound includes component (A), component (B), component (C), and other curable compounds that are optional components.

The content when the component (E) is included is, for example, 0.1 to 20% by weight with respect to the total amount of the curable compound and the total amount (100% by weight) of the component (E) contained in the photocurable composition. Yes, preferably 1 to 10% by weight, more preferably 2 to 8% by weight.

[Other ingredients]
The photocurable composition of the present invention may contain other components in addition to the components (A) to (E) as long as the effects of the present invention are not impaired. Examples of other components include solvents, surface modifiers (leveling agents, surfactants), photosensitizers (eg, thioxanthone compounds), antifoaming agents, coupling agents (eg, silane coupling agents, etc.) ), Conventional additives such as decolorizers, inorganic fillers, flame retardants, UV absorbers, ion adsorbents, phosphors, mold release agents, dispersants, dispersion aids, adhesion promoters, antioxidants, etc. Can be mentioned. Among these, it is preferable to include a surface modifier, an ultraviolet absorber, and an antioxidant as additives. These can be used alone or in combination of two or more.

(Surface modifier)
When the photocurable composition of the present invention contains a surface modifier (leveling agent, surfactant), the wettability to the silicon mold can be improved, and foaming at the time of application is reduced. It is preferable in that Examples of the surface modifier include compounds used in surfactants, leveling agents and the like. Examples of the surface modifier include silicone-based, acrylic-based, and fluorine-based ones. Examples of the silicone-based surfactant include polyether-modified polydimethylsiloxane.

Examples of commercially available surface modifiers include trade names “BYK-UV3510”, “BYK-333”, “BYK-345”, “BYK-350”, “BYK-352”, “BYK-354” ( As mentioned above, Big Chemie Japan Co., Ltd.) etc. can be used.

The molecular weight of the surface modifier is, for example, 3000 or more, preferably from 4000 to 150,000, more preferably from 5000 to 100,000, still more preferably from 7000 to 100,000, particularly preferably from 10,000 to 50,000.

The amount of the surface modifier used is, for example, 0.01 to 3 parts by weight, preferably 0.03 to 1 with respect to the total amount (100 parts by weight) of the curable compound contained in the photocurable composition. Parts by weight. When the amount of the surface modifier used is within the above range, wettability to the silicon mold can be improved, and foaming at the time of application can be suppressed.

(solvent)
The present invention may contain a solvent. Examples of the (organic) solvent include ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, methyl lactate, ethyl lactate, ethylene glycol monomethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, Esters such as 3-methoxybutyl acetate and 1-methoxy-2-propyl acetate; ethylene glycol monoethyl ether, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monomethyl ether acetate , Ethers such as diethylene glycol monoethyl ether; 3-metho Alcohols such as sibutanol and 1-methoxy-2-propanol; ketones such as acetone, methyl ethyl ketone, methyl butyl ketone, and cyclohexanone; aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, cumene, and mesitylene Can do. These solvents can be used alone or in combination of two or more.

The boiling point of the solvent (at 760 mmHg) is, for example, from 80 to 170 ° C., preferably from 100 to 160 ° C., more preferably from 120 to 155 ° C. in terms of applicability and volatility. When two or more kinds of solvents are included, the proportion of the solvent having a boiling point of 160 ° C. or less is, for example, 90% by weight or more with respect to the total amount of the solvent (100% by weight) contained in the photocurable composition, preferably It is 95 weight% or more, More preferably, it is 98 weight% or more, More preferably, it is 100 weight%.

When the solvent is included (the total amount when two or more are included), the concentration of the nonvolatile components contained in the photocurable composition is 3 to 90% by weight (preferably 5 to 80% by weight). The viscosity of the photocurable composition of the present invention [at 25 ° C., at a shear rate of 20 (1 / s)] is preferably about 100 to 10,000 mPa · s (preferably by adding a solvent). Is preferably adjusted to 100 to 5000 mPa · s) from the viewpoint of improving coatability.

When the solvent is included, the content is, for example, 1 to 99% by weight, preferably 2 to 95% by weight, and more preferably 5 to 90% with respect to the total amount of the photocurable composition (100% by weight). % By weight. The content of the solvent is, for example, 1 to 10000 parts by weight, preferably 10 to 2000 parts by weight, and more preferably, with respect to the total amount (100 parts by weight) of the non-volatile components (for example, curable compound). 20 to 1000 parts by weight.

In the present invention, the proportion of components having an SP value of less than 9.0 and a molecular weight of less than 400 is, for example, 20% by weight or less with respect to the total amount (100% by weight) of nonvolatile components contained in the photocurable composition. Yes, preferably 10% by weight or less, more preferably 5% by weight or less, and even more preferably 3% by weight or less. When the ratio of components having an SP value of less than 9.0 and a molecular weight of less than 400 is within the above range, swelling of the mold by the photocurable composition can be suppressed. The unit of the SP value is (cal / cm ³ ) ^1/2 .

A cured product of the photocurable composition can be obtained by appropriately photocuring the photocurable composition for nanoimprinting of the present invention. Moreover, the hardened | cured material in which the pattern was formed on the board | substrate by the nanoimprint method etc. which are mentioned later can be obtained.

[Manufacturing method of optical components]
The method for producing an optical component of the present invention includes at least a step of applying a photocurable composition on a substrate (application step), and a step of photocuring (imprinting step) after contacting the applied coating film with a silicon mold. . In addition to the coating process and the imprint process, a pre-bake process, a mold release process, a post-cure process, a post-bake process, an etching process, and the like may be included, and processes other than those described above may be included. In general, a method including the coating step and the imprint step in the method of manufacturing an optical component is called a nanoimprint method.

The application step is a step of forming a coating film (a film of the photocurable composition) on the substrate by applying the photocurable composition onto the substrate. Examples of the coating method in this coating step include spin coating, roll coating, dip coating, die coating, curtain coating, spraying, and screen printing. Among these, the spin coating method is preferable because a thin film can be easily formed. The coating conditions for forming the coating film by the spin coating method include, for example, a substrate rotation speed of about 300 to 5000 rpm, an initial rotation speed of 300 to 1000 rpm, and rotation for about 5 to 20 seconds, and then 3000 to 5000 rpm. An example is a condition in which the solvent is blown by rotating for 20 seconds or more. The temperature during spin coating is preferably about 20 to 28 ° C., for example.

The thickness of the coating film is, for example, 5 nm to 5 μm, preferably 20 nm to 4 μm, more preferably 30 nm to 3 μm, and further preferably 100 nm to 3 μm. In addition, the thickness of the said coating film is the thickness after hardening (hardened | cured material) after an imprint process.

The substrate may be any substrate used as a semiconductor substrate, and may be a substrate used in normal nanoimprinting. Specific examples include transparent inorganic substrates such as glass, silica glass, quartz, and sapphire, transparent synthetic resin substrates such as polycarbonate, polyethylene terephthalate (PET), and triacetyl cellulose, semiconductor substrates such as silicon wafers, GaAs, InAs, Examples thereof include compound semiconductors such as GaN, metals, metal oxides, and the like.

After the coating process, if necessary, a pre-baking process may be provided in order to volatilize excess solvent from the coating film formed in the coating process to obtain a hardness (viscosity) suitable for the subsequent imprint process. Pre-baking can be performed, for example, by appropriately heating the substrate with a hot plate or the like. The temperature in pre-baking is, for example, about 50 to 200 ° C., and the time is about 1 to 5 minutes.

The imprint process is a process in which the coating film after the coating process and the silicon mold are brought into contact with each other and photocured, and a process for transferring a pattern of the silicon mold and forming a cured product having a desired pattern on the substrate. It is. As the silicon mold, a silicon mold using polydimethylsiloxane as a raw material is preferable. Moreover, in order to improve the mold release property of the silicon mold, the mold surface may be subjected to a mold release treatment. The pattern shape of the mold is preferably a shape that can give the substrate the effect of improving the light extraction efficiency generated in the light emitting layer, and examples thereof include a trapezoidal shape, a conical shape, and a round shape. .

In the imprint process, as a method of bringing the coating film into contact with the silicon mold, the coating film may be pressed against the mold, the mold may be pressed against the coating film, or both the coating film and the mold may be pressed. . The force for pressing the coating film or the mold is, for example, about 0.01 to 5 MPa. Moreover, the pressure by the weight of a mold or a coating film may be applied without applying force.

In the method for manufacturing an optical component of the present invention, it is necessary to use at least one of a substrate or a silicon mold that is transparent to light used for curing in an imprint process.

The light source in the case of the said photocuring should just be what can irradiate the light of the wavelength which a coating film hardens | cures. Examples of the light source include a low pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, a xenon lamp, a carbon arc, a mercury xenon lamp, an excimer laser such as XeCl, KrF, and ArF, an ultraviolet light laser, and a UV-LED. Etc. Among these, a UV-LED (wavelength: 350 to 400 nm) is preferable as the light source because the coating film can be cured efficiently in a short time. The light irradiation amount may be an amount that can cure the coating film, and is, for example, about 10 to 1000 mJ / cm ² . The coating film is irradiated with light from the side of the member that is substantially transparent to the irradiation light of the substrate and the mold. In addition, the apparatus (for example, semiconductor manufacturing apparatus) in the conventional nanoimprint can also be used for the imprint process including this photocuring.

The mold release process is a process of releasing the cured product after the imprint process from the silicon mold, and is a process of obtaining a cured product in which the shape of the mold is transferred onto the surface of the substrate.

A post-cure process may be included after the imprint process and before or after the mold release process. Post-curing can improve shape stability and etching reproducibility. Post-cure can be performed by heating or light irradiation. When post-curing is performed by heating, it is preferable to heat at 50 to 180 ° C. for about 30 seconds to 3 hours, for example. When post-cure is performed by light irradiation, it is preferable to irradiate for about 3 to 100 seconds with an irradiation intensity of about 10 to 200 mW / cm ² , for example. As the light source in the light irradiation, those mentioned above can be used.

The post-baking step is a step performed by evaporating and removing volatile components (for example, a solvent) remaining on the surface and the like in the cured product after the mold release step and further improving the adhesion between the cured product and the substrate. It is performed by heating with an oven or a hot plate. The temperature in the post-baking is, for example, about 80 to 200 ° C., and the time is about 1 to 30 minutes.

The etching step is a step of processing (etching) the shape by chemically reacting the substrate with a chemical solution, a reactive gas, ions, or the like using the cured product as a mask after the post-bake step or the release step. Examples of the etching method include a dry etching method and a wet etching method. In particular, it is preferable to employ a dry etching method, and it is particularly preferable to employ reactive ion etching (RIE) in terms of enabling highly accurate fine processing.

Examples of the optical component obtained by the method for manufacturing an optical component of the present invention include an optical component (for example, a light emitting diode (LED), a solar cell, an antireflection film) provided with the above-described substrate such as sapphire.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples. The molecular weight in Table 1, the number-average molecular weight; a (M _n standard polystyrene by GPC), SP value is a value calculated by the calculation method described below SP value. Moreover, the unit of each component in Table 1 is parts by weight.

[Examples 1 to 6 and Comparative Examples 1 to 4]
The photocurable composition was prepared by mixing each component in the ratio shown in Table 1 below. Each photocurable composition was evaluated for the following curability, coating uniformity, pattern shape change (when imprint transfer was repeated), and transfer pattern appearance (after 50 times transfer). These evaluation results are shown in Table 1.

(SP value calculation method)
The SP value (solubility parameter) of each compound in Table 1 is a value at 25 ° C. according to the method of Fedors, and the unit is (cal / cm ³ ) ^1/2 . Polym. Eng. Sci., 14, 147 (1974). Specifically, it was calculated by the following formula. Note that the evaporation energy and molar volume of atoms or atomic groups are known values from the above-mentioned documents and the like.

e _i : Evaporation energy of atom or atomic group v _i : Molar volume of atom or atomic group

(Curable)
With respect to 5 g of the photocurable composition, 1-methoxy-2-propyl acetate (trade name “MMPGAC”, manufactured by Daicel Corporation, boiling point: 145 to 146 ° C.) is diluted at a rate of 10 g. The diluted solution was applied on a silicon wafer using a spin coater for 10 seconds at a rotation speed of 500 rpm and then at a rotation speed of 3000 rpm for 20 seconds to form a coating film (film thickness: 1 μm). After coating, the sample was allowed to stand for 1 hour in an environment of 23 ° C. and 50% RH, and the obtained coating film was subjected to 500 mJ / cm using an ultraviolet irradiation device (trade name “365 nm LED UNIT”, manufactured by USHIO INC.). ^A cured product was formed on the silicon wafer by irradiating ultraviolet rays having an accumulated light quantity of ² . The curability of this cured product was evaluated by touch dryness (touching the surface with a finger).
Evaluation criteria ○ (high curability): No stickiness. There is no trace of finger touch.
X (Poor curability): Stickiness The trace of finger touch remains.

(Coating uniformity)
A cured product was formed on the silicon wafer in the same manner as the above curability. The thickness of the obtained cured product was measured using a step gauge (trade name “T-4000”, manufactured by Kosaka Laboratory Co., Ltd.), and positioned 2 mm inward from the center (T ₁ ) and the outermost periphery. The difference in (T ₂ ) (T ₁ -T ₂ ) was taken as a step, and the coating uniformity was evaluated according to the following criteria.
Evaluation criteria ○ (good uniformity): when the step (T ₁ -T ₂ ) is 0.020 μm or less Δ (uniformity is slightly bad): the step (T ₁ -T ₂ ) exceeds 0.020 μm, 0 .050 μm or less × (poor uniformity): step (T ₁ −T ₂ ) exceeds 0.050 μm

(Pattern shape change (when imprint transfer is repeated))
A silicone mold (with a pattern of height: 2.0 μm, diameter: 1.0 μm, pitch width: 2.0 μm) was pressed from above onto the coating film obtained in the same manner as the above-mentioned curability, and the above-mentioned curing In the same manner as in the above, ultraviolet rays were irradiated, and then the silicon mold was released to form a cured product with a pattern on the silicon wafer. Using the same silicon mold, the above work (imprint transfer) was performed 10 times in total, and the pattern height of the first cured product was compared with the pattern height of the 10th cured product. The magnitude of change was evaluated. The pattern height was measured using a three-dimensional optical profiler system (trade name “New View 3600”, manufactured by Zygo Corporation). Five patterns were measured from two arbitrary locations, and the measured values at a total of 10 locations were averaged to obtain the pattern height.
Evaluation criteria ○ (good): (first pattern height / 10th pattern height) ratio of 0.95 to 1.05 Δ (slightly bad): (first pattern height / 10th pattern height) The ratio of (pattern height) is 0.90 or more and less than 0.95 × (bad): the ratio of (first pattern height / tenth pattern height) is less than 0.90.

(Appearance of transfer pattern (after 50 times transfer))
In the same manner as the pattern shape change (when imprint transfer is repeated), formation of a cured product with a pattern on a 4-inch silicon wafer (imprint transfer) is performed 50 times continuously using the same silicon mold. Carried out. The surface of the 50th cured product pattern was visually observed.
Evaluation criteria ○ (good appearance): There is uniform light interference unevenness on the entire surface, and there is no pattern defect.
X (Poor appearance): There is a partially non-uniform place in the light interference unevenness, and a pattern defect is suspected.

Abbreviations in Table 1 are as follows.
GT401: Epoxidized butanetetracarboxylic acid tetrakis- (3-cyclohexenylmethyl) modified epsilon-caprolactone, trade name “Epolide GT401” (manufactured by Daicel Corporation)
OXT-101: 3-ethyl-3-hydroxymethyloxetane, trade name “Aron Oxetane OXT-101” (manufactured by Toagosei Co., Ltd.)
OXBP: 4,4′-bis [(3-ethyl-3-oxetanyl) methoxymethyl] biphenyl, trade name “ETERRNACOLL OXBP” (manufactured by Ube Industries, Ltd.)
NC-3000H: biphenol type epoxy resin, trade name “NC-3000-H” (manufactured by Nippon Kayaku Co., Ltd.)
N-890: Modified novolak type epoxy resin, trade name “EPICLON N-890” (manufactured by DIC Corporation)
PB3600: Epoxidized polybutadiene, trade name “Epolide PB3600” (manufactured by Daicel Corporation)
(E-1): Diethylene glycol, boiling point: 244 ° C
(E-2): 1,4-cyclohexanedimethanol, boiling point: 162 ° C.
CELLOXIDE2000: 1,2-epoxy-4-vinylcyclohexane, trade name “Celoxide 2000” (manufactured by Daicel Corporation)
OXT-221: 3-ethyl-3 {[(3-ethyloxen-3-yl) methoxy] methyl} oxetane, trade name “Aron Oxetane OXT-221” (manufactured by Toagosei Co., Ltd.)
EX-121: 2-ethylhexyl glycidyl ether, trade name “Denacol EX-121” (manufactured by Nagase ChemteX Corporation)
(D-1): 4- (phenylthio) phenyldiphenylsulfonium phenyltris (pentafluorophenyl) borate (d-2): [4- (4-biphenylylthio) phenyl] -4-biphenylylphenylsulfonium tris (penta Fluorophenyl) trifluorophosphate in propylene glycol methyl ether acetate 50% solution (d-3): tris (4- (4-acetylphenyl) thiophenyl) sulfonium tetrakis (pentafluorophenyl) borate, molecular weight: 1393, trade name “Irgacure PAG290 "(manufactured by BASF Japan)
BYK350: polyacrylate-based surface modifier, molecular weight: about 20,000, trade name “BYK-350” (manufactured by BYK Japan Japan Co., Ltd.)

The photocurable composition for nanoimprinting of the present invention can be used as a composition for forming a fine pattern in a nanoimprinting method in a light emitting diode (LED) manufacturing process or the like.

Claims (8)

1. The following component (A), component (B), component (C), and component (D), and the content of the component (A) with respect to the total amount of the curable compound contained in the photocurable composition, A photocurable composition for nanoimprinting, which is 10 to 60% by weight, the content of the component (B) is 10% by weight or more, and the content of the component (C) is 10% by weight or more.
   Component (A): Fat having at least one partial structure represented by the following formula [a], a molecular weight of 400 or more, and a Fedors SP value of 9.0 (cal / cm ³ ) ^1/2 or more Cyclic epoxy compounds
   

   

   [Wherein, R ¹ to R ⁹ are the same or different and each represents a hydrogen atom, a halogen atom, an oxygen atom, a hydrocarbon group that may contain a halogen atom, or an alkoxy group that may have a substituent. . X represents an ester bond, an ether bond, a carbonyl group, a carbonate group, an alkylene group, an alkenylene group, or a combination of these bonds or groups]
   Component (B): Oxetane compound having an SP value of Fedors of 10.0 (cal / cm ³ ) ^1/2 or more, or a molecular weight of 400 or more (excluding compounds corresponding to component (A))
   Component (C): a cationic curable compound having a number average molecular weight of 1000 or more (excluding compounds corresponding to component (A) and component (B))
   Component (D): Photopolymerization initiator
2. The photocurable composition for nanoimprints according to claim 1, comprising a surface modifier.
3. The photocurable composition for nanoimprints according to claim 1 or 2, comprising a solvent.
4. The content of component (D) is 0.05 to 10 parts by weight with respect to the total amount (100 parts by weight) of the curable compound contained in the photocurable composition. The photocurable composition for nanoimprints described in 1.
5. An optical component comprising: a step of applying the photocurable composition for nanoimprinting according to any one of claims 1 to 4 on a substrate; and a step of bringing the applied coating film into contact with a silicon mold and photocuring the coating. Method.
6. The method for manufacturing an optical component according to claim 5, wherein a raw material of the silicon mold is polydimethylsiloxane.
7. The method of manufacturing an optical component according to claim 5 or 6, wherein the light source used for the photocuring is a UV-LED (wavelength: 350 to 400 nm).
8. The method for manufacturing an optical component according to any one of claims 5 to 7, further comprising an etching step.