阅读说明：本技术 光固化性组合物、凹凸结构体的制造方法、形成微细凹凸图案的方法及凹凸结构体 (Photocurable composition, method for producing uneven structure, method for forming fine uneven pattern, and uneven structure ) 是由 小田隆志 大喜田尚纪 和知浩子 山本慎吾 于 2020-03-31 设计创作，主要内容包括：一种光固化性组合物,其用于形成凹凸结构体的树脂层,所述凹凸结构体具备基板、以及设置于该基板上且表面形成有微细凹凸的所述树脂层。该光固化性组合物的固化膜的基于Kitazaki-Hata的理论测定得到的表面自由能为15mJ/m～(2)～40mJ/m～(2),使用纳米压痕仪测定得到的硬度为0.05GPa～0.5GPa。(A photocurable composition for forming a resin layer of a concavo-convex structure, the concavo-convex structure comprising a substrate and the resin layer provided on the substrate and having fine concavities and convexities formed on a surface thereof. The surface free energy of the cured film of the photocurable composition was 15mJ/m as determined by Kitazaki-Hata theory 2 ～40mJ/m 2 Measured by a nanoindenterThe hardness of (B) is 0.05 GPa-0.5 GPa.)

1. A photocurable composition for forming a resin layer of a concavo-convex structure, the concavo-convex structure comprising a substrate and the resin layer provided on the substrate and having fine concavities and convexities formed on the surface thereof,

the surface free energy of the photocurable composition measured by the following evaluation method 1 was 15mJ/m²～40mJ/m²The hardness measured by the following evaluation method 2 was 0.05GPa to 0.5GPa,

evaluation method 1:

first, a photocurable composition is applied to a substrate to form a photocurable film, and the photocurable film is irradiated with ultraviolet light to obtain a cured film,

next, using a contact angle meter, the contact angles of water, diiodomethane and 1-bromonaphthalene with respect to the cured film were measured respectively,

then, calculating the surface free energy by the Kitazaki-Hata theory;

evaluation method 2:

first, a cured film was obtained in the same manner as in the above-described evaluation method 1,

next, a berkovich indenter was pressed against the cured film using a nanoindenter, and the hardness was calculated from the detected stress value.

2. The photocurable composition according to claim 1, comprising:

(a) a photocurable monomer, or a photocurable monomer and a binder resin; and

(b) an additive having a photoreactive functional group,

the content of the additive having a photoreactive functional group (b) is 0.001 to 10% by mass relative to the total amount of the photocurable monomer (a) or the photocurable monomer and the binder resin and the additive having a photoreactive functional group (b).

3. The photocurable composition according to claim 2, wherein the (b) additive having a photoreactive functional group comprises: an additive represented by the following general formula (1) and/or an additive containing a structure represented by the following general formula (2),

[ solution 1]

In the general formula (1) above,

R₁the same or different, represents any atom or group selected from the group consisting of a hydrogen atom, a fluorine atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 6 to 20 carbon atoms, a polyether group having 1 to 20 carbon atoms and a fluorocarbon group having 1 to 20 carbon atoms,

L₁at least 1 of which contains a photoreactive functional group selected from the group consisting of an epoxy group, a hydroxyl group, an amino group, a vinyl ether group, a lactone group, a propenyl ether group, an olefin group, an oxetane group, a vinyl group, an acrylate group, a carbinol group and a carboxyl group, in L₁The same or different, when not a photoreactive functional group, represents a group selected from the group consisting of the above-mentioned R₁The atom or group (b) in (b),

n and 1-n represent the ratio of the units,

[ solution 2]

In the general formula (2), in the formula,

L₂is a photoreactive functional group selected from the group consisting of an epoxy group, an amino group, a vinyl ether group, a lactone group, a propenyl ether group, an alcohol group, an olefin group, an oxetane group, a vinyl group, an acrylate group, a carbinol group and a carboxyl group,

R₂～R₅at least 1 of the fluorine-containing groups is selected from the group consisting of fluorine, an alkyl group having 1 to 10 carbon atoms and containing fluorine, an alkoxy group having 1 to 10 carbon atoms and containing fluorine, and an alkoxyalkyl group having 2 to 10 carbon atoms and containing fluorine,

at R₂～R₅In the case where R is not a fluorine-containing group₂～R₅An organic group selected from the group consisting of hydrogen, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms and an alkoxyalkyl group having 2 to 10 carbon atoms,

R₂～R₅may be the same or different, and R is₂～R₅Can be combined with each other to form a ring structure,

the dotted line indicates that the bond of the moiety may be either a carbon-carbon single bond or a carbon-carbon double bond.

4. The photocurable composition according to any one of claims 1-3, comprising a photocuring initiator.

5. The photocurable composition according to claim 2 or 3, wherein the photocurable monomer comprises a compound having a ring-opening polymerizable group capable of cationic polymerization.

6. A method for producing a concave-convex structure using the photocurable composition according to any one of claims 1-5, the concave-convex structure comprising a substrate and a resin layer provided on the substrate and having fine concave-convex formed on the surface thereof,

the method for manufacturing the uneven structure body comprises the following steps:

and a pressure bonding step of pressure bonding a mold having a fine uneven pattern to a photocurable layer provided on a substrate with the photocurable composition, thereby forming a fine uneven pattern corresponding to the fine uneven pattern on the surface of the resin layer.

7. The method of manufacturing a concave-convex structure according to claim 6, further comprising the steps of:

a light irradiation step of irradiating light after the pressure bonding step in a state where the mold is pressure bonded, thereby curing the photocurable layer to produce a cured layer; and

a peeling step of peeling the mold from the cured layer.

8. A method for forming a fine uneven pattern by repeatedly using a substrate comprising a resin layer having fine unevenness formed on the surface thereof, the resin layer being formed from the photocurable composition according to any one of claims 1 to 5.

9. A concave-convex structure body is provided with:

a substrate; and

a resin layer which is provided on the substrate, is formed from the photocurable composition according to any one of claims 1 to 5, and has a fine uneven surface formed thereon.

Technical Field

The present invention relates to a photocurable composition, a method for producing an uneven structure, a method for forming a fine uneven pattern, and an uneven structure.

Background

As a method for forming a fine uneven pattern on the surface of a substrate, a photolithography method and a nanoimprint method are known.

The photolithography apparatus is expensive and the process is complicated. In contrast, the nanoimprint method has an advantage that a fine uneven pattern can be formed on the surface of the substrate by a simple apparatus and process. The nanoimprint method is considered to be a preferable method for forming a wide and deep concave-convex structure, a dome shape, a quadrangular pyramid, a triangular pyramid, and other various shapes.

In general, in an industrial nanoimprint method, an expensive master mold having a fine uneven structure on the surface formed by a photolithography method or an electron beam lithography method is first produced. Next, an inexpensive replica mold obtained by replicating the uneven structure of the master mold with an organic material is manufactured. In consideration of productivity, the replica mold finishes its task after processing the substrate to be processed for a certain number of repeated uses. In the industry, replica molds require a function that can withstand repeated use. By increasing the number of times of reuse, cost reduction is facilitated.

As a specific process of the nanoimprint method, a UV method is widely used in which a photocurable composition is brought into contact with the uneven surface of a mold, cured by light (UV) irradiation, and then peeled off. The UV mode is different from the heating melting crimping mode, and has the advantages of no need of large-scale heating and crimping equipment, easy construction of a roll-to-roll continuous method and the like.

A material having relatively good reproducibility when applied as a replica mold is disclosed (for example, patent document 1).

According to this document, a composition containing an acrylic ester, a silicone-based macromonomer, and an initiator is heated and polymerized, and the obtained resin composition is brought into contact with the uneven surface of a master mold, thereby producing a transfer mold by a hot melt pressure bonding method. Further, in UV type nanoimprinting with a photocurable compound, relatively good reproducibility of about 20 times was achieved.

However, the material described in patent document 1 needs to be heated, melted, and pressure-bonded when a replica mold is produced. That is, even when the uneven structure having a pattern region of several centimeters square is formed, in order to fill the resin into the uneven structure of the mold, a pressure of up to 20MPa needs to be applied by a device having a heating mechanism. Therefore, from the viewpoint of a method for producing a replica mold, the application to an industrial process is very limited.

Further, as a material applicable to UV-type nanoimprinting, patent document 2 discloses a specific cationic curing material as a material excellent in coatability, quick curability, thin-film curability, and shape transferability in the nanoimprinting method. Patent document 2 discloses that the repeated transferability can be used 50 times.

However, patent document 2 relates to imprinting in which the pattern shape is 1 to 2 μm in size. There is no description about the formation of patterns on the order of nanometer size.

Further, in any of the disclosed examples, application of the replica mold is not described in which the same material as that used for producing the replica mold is used and the replica mold produced first is reused.

Documents of the prior art

Patent document

Patent document 1: international publication No. 2012/018043

Patent document 2: japanese patent laid-open publication No. 2018-141028

Disclosure of Invention

Problems to be solved by the invention

As a result of the knowledge of the present inventors, the conventional techniques have not satisfied all the requirements from the viewpoint of the entire process including the production process of the replica mold and the degree of freedom in the shape (size) of the substrate to be processed, in the application of the nanoimprint method to the industrial production method. In particular, there is room for improvement in photocurable compositions used for forming resin molds for nanoimprinting, such as replica molds.

The present invention has been made in view of the above circumstances. Specifically, an object of the present invention is to provide a photocurable composition for forming a resin mold that can be repeatedly used in application as a replica mold.

Means for solving the problems

The present invention is as follows.

1. A photocurable composition which is a resin layer for forming a concavo-convex structure comprising a substrate and the resin layer provided on the substrate and having fine concavities and convexities formed on the surface thereof,

the surface free energy of the photocurable composition measured by the following evaluation method 1 was 15mJ/m²～40mJ/m²The hardness measured by the following evaluation method 2 was 0.05GPa to 0.5 GPa.

(evaluation method 1)

First, a photocurable composition is applied to a substrate to form a photocurable film, and the photocurable film is irradiated with ultraviolet light to obtain a cured film.

Next, the contact angles of water, diiodomethane and 1-bromonaphthalene with respect to the above cured film were measured using a contact angle meter, respectively.

Then, the surface free energy was calculated from Kitazaki-Hata's theory.

(evaluation method 2)

First, a cured film was obtained in the same manner as in the above evaluation method 1.

Next, a Berkovich (Berkovich) indenter was pressed against the cured film using a nanoindenter, and the hardness was calculated from the detected stress value.

2.

The photocurable composition according to claim 1, which comprises:

(a) a photocurable monomer, or a photocurable monomer and a binder resin; and

(b) an additive having a photoreactive functional group,

the content of the additive having a photoreactive functional group (b) is 0.001 to 10% by mass relative to the total amount of the photocurable monomer (a) or the photocurable monomer and the binder resin and the additive having a photoreactive functional group (b).

3.

The photocurable composition according to claim 2, wherein the additive (b) having a photoreactive functional group comprises: an additive represented by the following general formula (1) and/or an additive containing a structure represented by the following general formula (2).

[ solution 1]

In the general formula (1) above,

R₁the same or different, represents any atom or group selected from the group consisting of a hydrogen atom, a fluorine atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 6 to 20 carbon atoms, a polyether group having 1 to 20 carbon atoms and a fluorocarbon group having 1 to 20 carbon atoms,

L₁at least 1 of which contains a photoreactive functional group selected from the group consisting of an epoxy group, a hydroxyl group, an amino group, a vinyl ether group, a lactone group, a propenyl ether group, an olefin group, an oxetane group, a vinyl group, an acrylate group, a carbinol group and a carboxyl group, in L₁The same or different R's are selected from the above-mentioned groups when not being a photoreactive functional group₁The atom or group (b) in (b),

n and 1-n represent the ratio of the units.

[ solution 2]

In the general formula (2), in the formula,

L₂is a photoreactive functional group selected from the group consisting of an epoxy group, an amino group, a vinyl ether group, a lactone group, a propenyl ether group, an alcohol group, an olefin group, an oxetane group, a vinyl group, an acrylate group, a carbinol group and a carboxyl group,

R₂～R₅at least 1 of the fluorine-containing groups is selected from the group consisting of fluorine, an alkyl group having 1 to 10 carbon atoms and containing fluorine, an alkoxy group having 1 to 10 carbon atoms and containing fluorine, and an alkoxyalkyl group having 2 to 10 carbon atoms and containing fluorine,

at R₂～R₅In the case where R is not a fluorine-containing group₂～R₅An organic group selected from the group consisting of hydrogen, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms and an alkoxyalkyl group having 2 to 10 carbon atoms,

R₂～R₅may be the same or different, and R is₂～R₅Can be combined with each other to form a ring structure,

the dotted line indicates that the bond of the moiety may be either a carbon-carbon single bond or a carbon-carbon double bond.

4.

The photocurable composition according to any one of claims 1 to 3, which comprises a photocurable initiator.

5.

The photocurable composition according to claim 2 or 3, wherein the photocurable monomer comprises a compound having a ring-opening polymerizable group capable of cationic polymerization.

6.

A method for producing an uneven structure using the photocurable composition according to any one of claims 1 to 5, the uneven structure comprising a substrate and a resin layer provided on the substrate and having fine unevenness formed on a surface thereof,

the method for manufacturing the uneven structure body comprises the following steps:

and a pressure bonding step of pressure bonding a mold having a fine uneven pattern to a photocurable layer provided on a substrate with the photocurable composition, thereby forming a fine uneven pattern corresponding to the fine uneven pattern on the surface of the resin layer.

7.

The method for manufacturing a concave-convex structure according to claim 6, further comprising the steps of:

a light irradiation step of irradiating light after the pressure bonding step in a state where the mold is pressure bonded, thereby curing the photocurable layer to form a cured layer; and

a peeling step of peeling the mold from the cured layer.

8.

A method for forming a fine uneven pattern by repeatedly using a substrate having a resin layer formed with fine unevenness on the surface thereof, the resin layer being formed from the photocurable composition according to any one of claims 1 to 5.

9.

A concave-convex structure body is provided with:

a substrate; and

a photocurable composition according to any one of claims 1 to4, which is provided on the substrate, and on the surface of which a resin layer having fine irregularities is formed.

ADVANTAGEOUS EFFECTS OF INVENTION

By using the photocurable composition of the present invention, a relief structure which can be repeatedly used in application as a replica mold can be obtained.

Drawings

FIG. 1 shows the result of mapping (mapping) the cross section of a replica B-1 prepared from the photocurable composition (1) described in example 1 by time-of-flight secondary ion mass spectrometry (TOF-SIMS).

Detailed Description

Hereinafter, embodiments of the present invention will be described.

The numerical range "a to B" means a to B unless otherwise specified. For example, the expression "1 to 5%" means 1% to 5%.

In the present specification, the photocurable composition of the present invention may be referred to as "1 st photocurable composition". In addition, a substrate having a resin layer with a fine uneven structure formed on the surface thereof using the 1 st photocurable composition may be used as a replica mold, and a photocurable composition used for processing a substrate to be processed using the replica mold may be referred to as a "2 nd photocurable composition".

In the expression of the group (atomic group) in the present specification, the expression of substituted or unsubstituted includes both the case of having no substituent and the case of having a substituent. For example, the term "alkyl group" encompasses not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).

< Photocurable composition >

The photocurable composition of the present embodiment is used for forming a resin layer in a concave-convex structure body including a substrate and a resin layer provided on the substrate and having fine concave-convex formed on a surface thereof.

The photocurable composition of the present embodiment preferably includes: (a) a photocurable monomer, or a photocurable monomer and a binder resin; and (b) an additive having a photoreactive functional group.

The content of the additive having a photoreactive functional group (b) is preferably 0.001 to 10% by mass based on the total amount of (a) and (b).

Hereinafter, each component capable of constituting the photocurable composition will be described. The photocurable composition of the present embodiment preferably contains the components described below for the sake of caution, but may not contain the components described below as long as the characteristic values measured by the following (evaluation method 1) and (evaluation method 2) are within predetermined ranges.

(Photocurable monomer)

Examples of the photocurable monomer include a compound having a reactive double bond group, a ring-opening polymerizable compound capable of cationic polymerization, and the like. Particularly preferred is a ring-opening polymerizable compound (specifically, a compound containing a ring-opening polymerizable group such as an epoxy group or an oxetane group) which has a small curing shrinkage and a good dimensional reproducibility of a concavo-convex shape and can be cationically polymerized.

The photocurable monomer may have 1 reactive group or a plurality of reactive groups in 1 molecule. It is preferable to use a compound having 2 or more reactive groups in 1 molecule. The number of the reactive groups in 1 molecule is not particularly limited, but is, for example, 2, preferably 4.

Only 1 kind of the photocurable monomer may be used, or 2 or more kinds may be used. When 2 or more compounds are used, compounds having different numbers of reactive groups may be mixed at an arbitrary ratio and used. Further, a compound having a reactive double bond group and a ring-opening polymerizable compound capable of cationic polymerization may be mixed at an arbitrary ratio and used.

Further, by appropriately selecting the type and composition ratio of the photocurable monomer, a three-dimensional network structure can be efficiently formed inside and on the surface after curing by light irradiation. This makes it possible to maintain the resin hardness, which will be described later, within an appropriate range.

Specific examples of the case where the photocurable monomer is a compound having a reactive double bond group include the following compounds.

Fluorodiene (CF)₂＝CFOCF₂CF₂CF＝CF₂、CF₂＝CFOCF₂CF(CF₃)CF＝CF₂、CF₂＝CFCF₂C(OH)(CF₃)CH₂CH＝CH₂、CF₂＝CFCF₂C(OH)(CF₃)CH＝CH₂、CF₂＝CFCF₂C(CF₃)(OCH₂OCH₃)CH₂CH＝CH₂、CF₂＝CFCH₂C(C(CF₃)₂OH)(CF₃)CH₂CH＝CH₂Etc.) olefins.

Cyclic olefins such as norbornene and norbornadiene.

Alkyl vinyl ethers such as cyclohexyl methyl vinyl ether, isobutyl vinyl ether, cyclohexyl vinyl ether and ethyl vinyl ether.

Vinyl esters such as vinyl acetate.

(meth) acrylic acid, phenoxyethyl acrylate, benzyl acrylate, stearyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, allyl acrylate, 1, 3-butanediol diacrylate, 1, 4-butanediol diacrylate, 1, 6-hexanediol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol hexaacrylate, ethoxyethyl acrylate, methoxyethyl acrylate, glycidyl acrylate, tetrahydrofurfuryl acrylate, diethylene glycol diacrylate, neopentyl glycol diacrylate, polyoxyethylene glycol diacrylate, tripropylene glycol diacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl vinyl ether, N-diethylaminoethyl acrylate, poly (t-butyl) acrylate, poly (t-butyl acrylate), poly (t-butyl) acrylate, poly (t-butyl acrylate), poly (1, poly (t-butyl) acrylate), poly (t-butyl acrylate), poly (1, poly (t-butyl acrylate), poly (t-butyl acrylate), poly (t-acrylate, (meth) acrylic acid and its derivatives, fluorine-containing acrylates thereof, polyfunctional acrylates thereof, and the like, such as N, N-dimethylaminoethyl acrylate, N-vinylpyrrolidone, dimethylaminoethyl methacrylate, methyl methacrylate, trifluoroethyl methacrylate, benzyl methacrylate, and the like.

Among the photocurable monomers, examples of the ring-opening polymerizable compound capable of cationic polymerization include the following compounds. These are preferable from the viewpoint of long-term storage stability, suppression of deterioration in dimensional accuracy of the uneven structure due to curing shrinkage, and the like.

1, 7-octadiene diepoxide, 1, 2-epoxydecane, 1, 2-epoxydodecane, 2-ethylhexyl glycidyl ether, cyclohexene epoxide, alpha pinene oxide, dicyclopentadiene oxide, limonene monooxide, limonene dioxide, 4-vinylcyclohexene dioxide, 3, 4-epoxycyclohexylmethyl-3 ', 4' -epoxycyclohexanecarboxylate, bis (3, 4-epoxycyclohexyl) adipate, (3, 4-epoxycyclohexyl) methyl alcohol, 1, 2-epoxy-4-vinylcyclohexane, (3, 4-epoxy-6-methylcyclohexyl) methyl-3, 4-epoxy-6-methylcyclohexanecarboxylate, ethylene 1, 2-bis (3, 4-epoxycyclohexanecarboxylic acid) ester, [ (3, 4-epoxycyclohexane) -1-yl ] methyl methacrylate, (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, dicyclohexyl-3, 3' -diepoxide, bisphenol A-type epoxy resin, halogenated bisphenol A-type epoxy resin, bisphenol F-type epoxy resin, epoxidized polybutadiene, o-cresol novolak-type epoxy resin, m-cresol novolak-type epoxy resin, p-cresol novolak-type epoxy resin, phenol novolak-type epoxy resin, polyglycidyl ether of polyhydric alcohol, 1, 2-epoxy-4- (2-oxiranyl) cyclohexane adduct of 2, 2-bis (hydroxymethyl) -1-butanol, a copolymer of 2, 2-epoxy-4- (2-oxiranyl) cyclohexane, a copolymer of (A) and (B) a copolymer (A) obtained by reacting a polyhydric alcohol with a polyhydric alcohol and a polyhydric alcohol, Epoxy compounds such as adducts of 3, 4-epoxycyclohexylmethyl-3 ', 4' -epoxycyclohexanecarboxylate and epsilon-caprolactone, alicyclic epoxy resins such as bis (3, 4-epoxycyclohexan-1-ylmethyl) adipate and 3, 4-epoxycyclohexenylmethyl-3 ', 4' -epoxycyclohexenecarboxylate, and epoxy compounds such as glycidyl ethers and glycidyl esters of hydrogenated bisphenol A.

3-methyl-3- (butoxymethyl) oxetane, 3-methyl-3- (pentyloxymethyl) oxetane, 3-methyl-3- (hexyloxymethyl) oxetane, 3-methyl-3- (2-ethylhexyloxymethyl) oxetane, 3-methyl-3- (octyloxymethyl) oxetane, 3-methyl-3- (decyloxymethyl) oxetane, 3-methyl-3- (dodecyloxymethyl) oxetane, 3-methyl-3- (phenoxymethyl) oxetane, 3-ethyl-3- (butoxymethyl) oxetane, 3-ethyl-3- (pentyloxymethyl) oxetane, 3-ethyl-3- (hexyloxymethyl) oxetane, 3-ethyl-3- (2-ethylhexyloxymethyl) oxetane, 3-ethyl-3- (octyloxymethyl) oxetane, 3-ethyl-3- (decyloxymethyl) oxetane, 3-ethyl-3- (dodecyloxymethyl) oxetane, 3- (cyclohexyloxymethyl) oxetane, 3-methyl-3- (cyclohexyloxymethyl) oxetane, 3-ethyl-3- (phenoxymethyl) oxetane, p-ethyls-3- (hexyloxymethyl) oxetane, p-ethyls-, 3, 3-dimethyloxetane, 3-hydroxymethyloxetane, 3-methyl-3-hydroxymethyloxetane, 3-ethyl-3-phenoxymethyloxetane, 3-n-propyl-3-hydroxymethyloxetane, 3-isopropyl-3-hydroxymethyloxetane, 3-n-butyl-3-hydroxymethyloxetane, 3-isobutyl-3-hydroxymethyloxetane, 3-sec-butyl-3-hydroxymethyloxetane, 3-tert-butyl-3-hydroxymethyloxetane, 3-ethyl-3- (2-ethylhexyl) oxetane, 3-ethyl-3- [ (2-ethylhexyloxy) methyl ] oxetane, etc.; bis (3-ethyl-3-oxetanylmethyl) ether, 1, 2-bis [ (3-ethyl-3-oxetanylmethoxy) ] ethane, 1, 3-bis [ (3-ethyl-3-oxetanylmethoxy) ] propane, 1, 3-bis [ (3-ethyl-3-oxetanylmethoxy) ] -2, 2-dimethyl-propane, 1, 4-bis (3-ethyl-3-oxetanylmethoxy) butane, 1, 6-bis (3-ethyl-3-oxetanylmethoxy) hexane, 1, 4-bis [ (3-methyl-3-oxetanyl) methoxy ] benzene, 1, 4-bis (3-methyl-3-oxetanyl) methoxy ] benzene, 1, 3-bis [ (3-methyl-3-oxetanyl) methoxy ] benzene, 1, 4-bis { [ (3-methyl-3-oxetanyl) methoxy ] methyl } cyclohexane, 4 '-bis { [ (3-methyl-3-oxetanyl) methoxy ] methyl } biphenyl, 4' -bis { [ (3-methyl-3-oxetanyl) methoxy ] methyl } bicyclohexane, 2, 3-bis [ (3-methyl-3-oxetanyl) methoxy ] bicyclo [2.2.1] heptane, 2, 5-bis [ (3-methyl-3-oxetanyl) methoxy ] bicyclo [2.2.1] heptane, 2, 6-bis [ (3-methyl-3-oxetanyl) methoxy ] bicyclo [2.2.1] heptane, 1, 4-bis [ (3-ethyl-3-oxetanyl) methoxy ] benzene, 1, 3-bis [ (3-ethyl-3-oxetanyl) methoxy ] benzene, 1, 4-bis { [ (3-ethyl-3-oxetanyl) methoxy ] methyl } cyclohexane, 4 ' -bis { [ (3-ethyl-3-oxetanyl) methoxy ] methyl } biphenyl, 4 ' -bis { [ (3-ethyl-3-oxetanyl) methoxy ] methyl } bicyclohexane, 4 ' -bis { [ (3-ethyl-3-oxetanyl) methoxy ] methyl } bicyclohexane, Oxetane compounds such as 2, 3-bis [ (3-ethyl-3-oxetanyl) methoxy ] bicyclo [2.2.1] heptane, 2, 5-bis [ (3-ethyl-3-oxetanyl) methoxy ] bicyclo [2.2.1] heptane, 2, 6-bis [ (3-ethyl-3-oxetanyl) methoxy ] bicyclo [2.2.1] heptane and xylylene dioxirane.

Lactone compounds.

Propenyl ether compounds, and the like.

When the entire photocurable composition is referred to as a reference (100 mass%), the content of the photocurable monomer in the photocurable composition is preferably 10 to 99.5 mass%, more preferably 20 to 99.5 mass%, and still more preferably 30 to 99.5 mass%. When the binder resin described later is contained, the content is preferably 50 to 99.5% by mass, more preferably 60 to 99.5% by mass, and still more preferably 70 to 99.5% by mass. In either case, the photocurable monomer may be used alone, or 2 or more kinds may be used in combination.

By adjusting the content of the photocurable monomer within these ranges, a three-dimensional network structure can be effectively formed on the surface and/or inside of the cured resin layer. Further, the resin hardness described later can be easily adjusted to an appropriate range.

(Binder resin)

The binder resin is, for example, a polymer obtained by previously polymerizing the above-mentioned photocurable monomer, or a polymer obtained by polymerizing the above-mentioned photocurable monomer by another method.

From the viewpoint of compatibility with a curable monomer, film properties after curing, and the like, the binder resin is preferably, for example, a polymer obtained by polymerizing the above-mentioned photocurable monomer in advance, or an amorphous cyclic olefin polymer.

Further, preferable examples of the binder resin include polyacrylic resins, polyether resins, polyoxetane resins, polyester resins, cyclic olefin polymers, and the like.

Examples of the cyclic olefin polymer include a fluorinated cyclic olefin polymer represented by the general formula (1) of Japanese patent No. 5466705. Unlike a general fluororesin, the fluorinated cyclic olefin polymer has a moderate dipole moment in terms of the characteristics of the arrangement of fluorine atoms and fluorine-containing substituents. Therefore, the fluororesin has characteristics as a fluororesin, and tends to have good compatibility with general-purpose organic solvents and other components in the photocurable composition. Therefore, the following advantages are provided: the composition is uniformly dissolved during preparation; the compatibility is good even in the form after light irradiation curing; a uniformly transparent cured resin layer and the like can be obtained without causing whitening and the like.

When the binder resin is used, the amount thereof is preferably 0.1 to 50% by mass, more preferably 0.5 to 40% by mass, and still more preferably 1 to 30% by mass, based on the entire photocurable composition (100% by mass). When a binder resin is used, 2 or more kinds thereof may be used alone or in combination.

The viscosity of the photocurable composition can be adjusted by adjusting the content of the binder resin within the above range. For example, the viscosity can be increased to suppress dripping of a liquid at the time of application, or to improve a problem of uniformity due to fluctuation of the application surface.

The weight average molecular weight of the binder resin is preferably 500 to 100000, more preferably 500 to 80000, and even more preferably 500 to 50000, in terms of GPC measurement of a polystyrene standard, from the viewpoint of compatibility with other components in the photocurable composition. By adjusting the weight average molecular weight of the binder resin within this range, the compatibility with other components in the photocurable composition is good, and a photocurable composition which can be stored stably for a long period of time can be easily obtained.

(additive having photoreactive functional group)

The additive having a photoreactive functional group is preferably unevenly distributed on the surface of the photocurable composition of the present embodiment when the photocurable composition is formed into a film. This enables adjustment of the surface free energy of the surface of the cured film described later.

The additive having a photoreactive functional group is preferably a compound that can be bonded to the photocurable monomer due to the presence of the photoreactive functional group. Thus, when the transfer mold is repeatedly used, the transfer of a part of the transfer mold to the 2 nd photocurable composition used for processing the substrate to be processed can be suppressed, and the surface properties of the transfer mold can be easily maintained to be good. That is, the reusability of the replica mold can be improved.

In addition, the additive having a photoreactive functional group is preferably unevenly distributed on the surface when forming the resin layer. According to the findings of the present inventors, for example, a siloxane compound described later and a fluoropolymer having a specific cyclic structure are effectively localized in the vicinity of the film surface due to the presence of silicon atoms and fluorine atoms. This makes it possible to control the surface free energy and hardness of the film surface. And the reusability of the replica mold is considered to be improved.

Examples of the additive having a photoreactive functional group include a compound having a reactive double bond group as a photoreactive functional group, a compound having a ring-opening polymerizable group capable of cationic polymerization, and the like. Preferably, the compound is a ring-opening polymerizable compound (specifically, a ring-opening polymerizable group such as an epoxy group, an oxetane group, an amino group, a vinyl ether group, or an alcohol group, or a compound capable of being directly bonded to a ring-opening polymerizable group) capable of cationic polymerization.

The additive having a photoreactive functional group may have 1 photoreactive group or a plurality of photoreactive groups in 1 molecule. The additive having a photoreactive functional group preferably has 2 or more photoreactive groups in 1 molecule. The number of the reactive groups in 1 molecule is not particularly limited, but is, for example, 2, preferably 4.

Only 1 kind of additive having a photoreactive functional group may be used, or 2 or more kinds may be used. When 2 or more compounds are used, compounds having different numbers of reactive groups may be mixed at an arbitrary ratio and used. Further, a compound having a reactive double bond group and a ring-opening polymerizable compound capable of cationic polymerization may be mixed at an arbitrary ratio and used.

In the photocurable composition, the content of the additive having a photoreactive functional group is preferably 0.001 to 10% by mass, more preferably 0.005 to 8% by mass, and still more preferably 0.01 to 5% by mass, based on the total amount (100% by mass) of the photocurable monomer(s) (a) or the photocurable monomer(s) and the binder resin(s) and the additive having a photoreactive functional group (b).

By adjusting the amount within this range, for example, the additive can be efficiently concentrated on the film surface. Further, the surface free energy described later can be easily adjusted to an appropriate range. In addition, in the production of the uneven structure, adhesion of resin is suppressed in the peeling step, and the peelability is improved. In addition, defects of the transfer mold can be suppressed, and the reusability can be improved.

An example of the additive having a photoreactive functional group is a siloxane compound having a photoreactive functional group. More specifically, the siloxane compound represented by the following general formula (1) is exemplified.

[ solution 3]

In the general formula (1) above,

R₁the same or different, represents any atom or group selected from the group consisting of a hydrogen atom, a fluorine atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 6 to 20 carbon atoms, a polyether group having 1 to 20 carbon atoms and a fluorocarbon group having 1 to 20 carbon atoms,

L₁at least 1 of which contains a photoreactive functional group selected from the group consisting of an epoxy group, a hydroxyl group, an amino group, a vinyl ether group, a lactone group, a propenyl ether group, an olefin group, an oxetane group, a vinyl group, an acrylate group, a carbinol group and a carboxyl group, in L₁When not a photoreactive functional group, the same or different groups are selected from R₁The atom or group (b) in (b),

n and 1-n represent the ratio of each unit, and n is usually in the range of 0 to 1.

As the siloxane compound having a photoreactive functional group, commercially available products can be used. For example, a polysiloxane having a photoreactive functional group at the end/side chain of the main chain, a compound corresponding to the general formula (1), or the like can be selected and used from commercially available siloxane compounds containing a reactive group, and the like.

Examples of commercially available products of the epoxy group-containing siloxane compound include X-22-343 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-101 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-1001 (manufactured by shin-Etsu Silicone Co., Ltd.), X-22-2000 (manufactured by shin-Etsu Silicone Co., Ltd.), X-22-2046 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-102 (manufactured by shin-Etsu Silicone Co., Ltd.), X-22-4741 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-1002 (manufactured by shin-Etsu Silicone Co., Ltd.), X-22-3000T (manufactured by shin-Silicone Co., Ltd.), X-22-163 (manufactured by shin-Silicone Co., Ltd.), KF-105 (manufactured by shin-Silicone Co., Ltd.), X-22-163A (manufactured by shin-Silicone Co., Ltd.), and X-22-163B (manufactured by shin-Silicone Co., Ltd.) X-22-163C (manufactured BY shin-Yue Silicone Co., Ltd.), X-22-169AS (manufactured BY shin-Yue Silicone Co., Ltd.), X-22-169B (manufactured BY shin-Yue Silicone Co., Ltd.), X-22-173DX (manufactured BY shin-Yue Silicone Co., Ltd.), X-22-9002 (manufactured BY shin-Yue Silicone Co., Ltd.), SF 8411 (manufactured BY Donglido Corning Co., Ltd.), SF 8413 (manufactured BY Donglido Corning Co., Ltd.), SF 8421 (manufactured BY Donglido Corning Co., Ltd.), BY16-839 (manufactured BY Donglido Corning Co., Ltd.), BY16-876 (manufactured BY Donglido Corning Co., Ltd.), FZ-3736 (manufactured BY Donglido Corning Co., Ltd.), and the like.

Specific examples of commercially available silicone compounds containing a hydroxyl group include YF3800 (manufactured by Momentive Performance Materials Japan), XF3905 (manufactured by Momentive Materials Japan Co., Ltd.), X-21-5841 (manufactured by shin-Transit Silicone Co., Ltd.), KF-9701 (manufactured by shin-Transit Silicone Co., Ltd.), FM-0411 (manufactured by JNC Co., Ltd.), FM-0421 (manufactured by JNC Co., Ltd.), FM-0425 (manufactured by JNC Co., Ltd.), FM-DA11 (manufactured by JNC Co., Ltd.), FM-DA21 (manufactured by JNC Co., Ltd.), FM-DA26 (manufactured by JNC Co., Ltd.), FM-4411 (manufactured by JNC Co., Ltd.), FM-4421 (manufactured by JNC Co., Ltd.), FM-4425 (manufactured by JNC Co., Ltd.), and the like.

Examples of commercially available products of the amino group-containing silicone compound include KF-868 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-865 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-864 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-859 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-393 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-860 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-880 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-8004 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-8002 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-8005 (manufactured by shin-Silicone Co., Ltd.), KF-862 (manufactured by shin-Etsu Silicone Co., Ltd.), X-223820W (manufactured by shin-Silicone Co., Ltd.), KF-869 (manufactured by shin-Silicone Co., Ltd.), KF-861-3939A (manufactured by shin-Silicone Co., Ltd.), and the like, KF-877 (manufactured by shin-Etsu Silicone Co., Ltd.), PAM-E (manufactured by shin-Etsu Silicone Co., Ltd.), KF-8010 (manufactured by shin-Etsu Silicone Co., Ltd.), X-22-161A (manufactured by shin-Etsu Silicone Co., Ltd.), X-22-161B (manufactured by shin-Etsu Silicone Co., Ltd.), KF-8012 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-8008 (manufactured by shin-Etsu Silicone Co., Ltd.), X-22-1660B-3 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-857 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-8001 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-862 (manufactured by shin-Etsu Silicone Co., Ltd.), X-22-9192 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-868 (manufactured by shin-Silicone Co., Ltd.), and the like.

Examples of commercially available products of the silanol group-containing silicone compound include X-22-4039 (manufactured by shin-Etsu Silicone Co., Ltd.), X-22-4015 (manufactured by shin-Etsu Silicone Co., Ltd.), X-22-160AS (manufactured by shin-Etsu Silicone Co., Ltd.), KF-6001 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-6002 (manufactured by shin-Etsu Silicone Co., Ltd.), KF-6003 (manufactured by shin-Etsu Silicone Co., Ltd.), X-22-170BX (manufactured by shin-Etsu Silicone Co., Ltd.), and X-22-170DX (manufactured by shin-Etsu Silicone Co., Ltd.).

Examples of commercially available products of the carboxyl group-containing silicone compound include X-22-3701E (manufactured by shin-Etsu Silicone Co., Ltd.), X-22-162C (manufactured by shin-Etsu Silicone Co., Ltd.), and X-22-3710 (manufactured by shin-Etsu Silicone Co., Ltd.).

Examples of commercially available products of acrylate group-containing silicone compounds include X-22-164 (manufactured by shin-Etsu Silicone Co., Ltd.), X-22-174BX (manufactured by shin-Etsu Silicone Co., Ltd.), X-22-2426 (manufactured by shin-Etsu Silicone Co., Ltd.), FM-0711 (manufactured by JNC Co., Ltd.), FM-0721 (manufactured by JNC Co., Ltd.), FM-7711 (manufactured by JNC Co., Ltd.), FM-7725 (manufactured by JNC Co., Ltd.), and TM-0701T (manufactured by JNC Co., Ltd.).

Among these, it is preferable to select a silicone compound containing an epoxy group capable of cationic polymerization and/or a silicone compound containing a hydroxyl group.

The siloxane compound preferably has a weight average molecular weight (Mw) of 200 to 50000, more preferably 200 to 40000, and still more preferably 200 to 30000. By adjusting the molecular weight within this range, the compatibility with other components in the photocurable composition is improved. Further, a sufficient surface segregation effect is easily obtained at the time of film formation.

The preferable range of n in the general formula (1) is 0 to 1, more preferably 0.1 to 1, and still more preferably 0.3 to 1. Consider R₁、L₁The kind of (b) and compatibility with other components constituting the photocurable composition (compatibility, curability, repeated compatibility of the replica mold to be produced, etc.) are appropriately selected.

Other examples of the additive having a photoreactive functional group include a fluorinated cyclic olefin polymer (specifically, a fluorinated cyclic olefin polymer having a photoreactive functional group in a side chain/terminal). More specifically, the fluorinated cyclic olefin polymer may be a specific fluorinated cyclic olefin polymer represented by the general formula (2).

[ solution 4]

In the general formula (2), in the formula,

L₂is a photoreactive functional group selected from the group consisting of an epoxy group, an amino group, a vinyl ether group, a lactone group, a propenyl ether group, an alcohol group, an olefin group, an oxetane group, a vinyl group, an acrylate group, a carbinol group and a carboxyl group,

R₂～R₅at least 1 of the fluorine-containing groups is selected from the group consisting of fluorine, an alkyl group having 1 to 10 carbon atoms and containing fluorine, an alkoxy group having 1 to 10 carbon atoms and containing fluorine, and an alkoxyalkyl group having 2 to 10 carbon atoms and containing fluorine,

at R₂～R₅In the case where R is not a fluorine-containing group₂～R₅Is selected from the group consisting of hydrogen, alkyl group having 1 to 10 carbon atoms, alkoxy group having 1 to 10 carbon atoms and alkoxy group having 2 to 10 carbon atomsAn organic group in the group consisting of an alkyl group,

R₂～R₅may be the same or different, and R is₂～R₅Can be combined with each other to form a ring structure,

the dotted line indicates that the bond of the moiety may be either a carbon-carbon single bond or a carbon-carbon double bond.

In the general formula (2), in R₂～R₅When the group is a fluorine-containing group, specific examples thereof include fluorine; an alkyl group having 1 to 10 carbon atoms, in which a part or all of hydrogen in an alkyl group such as a fluoromethyl group, difluoromethyl group, trifluoromethyl group, trifluoroethyl group, pentafluoroethyl group, heptafluoropropyl group, hexafluoroisopropyl group, heptafluoroisopropyl group, hexafluoro-2-methylisopropyl group, perfluoro-2-methylisopropyl group, n-perfluorobutyl group, n-perfluoropentyl group, or perfluorocyclopentyl group is substituted with fluorine; an alkoxy group having 1 to 10 carbon atoms, in which a part or all of hydrogen in an alkoxy group such as a fluoromethoxy group, difluoromethoxy group, trifluoromethoxy group, trifluoroethoxy group, pentafluoroethoxy group, heptafluoropropoxy group, hexafluoroisopropoxy group, heptafluoroisopropoxy group, hexafluoro-2-methylisopropoxy group, perfluoro-2-methylisopropoxy group, n-perfluorobutoxy group, n-perfluoropentyloxy group, or perfluorocyclopentyloxy group is substituted with fluorine; and alkoxyalkyl groups having 2 to 10 carbon atoms in which a part or all of the hydrogens of an alkoxyalkyl group such as fluoromethoxymethyl, difluoromethoxymethyl, trifluoromethoxy methyl, trifluoroethoxymethyl, pentafluoroethoxymethyl, heptafluoropropoxymethyl, hexafluoroisopropoxymethyl, heptafluoroisopropoxymethyl, hexafluoro-2-methylisopropoxymethyl, perfluoro-2-methylisopropoxymethyl, n-perfluorobutoxymethyl, n-perfluoropentyloxymethyl, perfluorocyclopentyloxymethyl and the like are substituted with fluorine.

R₂～R₅May be bonded to each other to form a ring structure. For example, a perfluorocycloalkyl ring, an intermediate oxygen perfluorocyclic ether, or the like may be formed.

At R₂～R₅In the case where it is not a fluorine-containing group, as R₂～R₅Specific examples thereof include hydrogen; c1-carbon atom such as methyl, ethyl, propyl, isopropyl, 2-methylisopropyl, n-butyl, n-pentyl and cyclopentylAn alkyl group of about 10; alkoxy groups having 1 to 10 carbon atoms such as methoxy, ethoxy, propoxy, butoxy, pentoxy and the like; and C2-10 alkoxyalkyl groups such as methoxymethyl, ethoxymethyl, propoxymethyl, butoxymethyl, and pentoxymethyl.

R as formula (2)₂～R₅Preferably, it is fluorine; and fluoroalkyl groups having 1 to 10 carbon atoms in which a part or all of hydrogen in an alkyl group such as a fluoromethyl group, difluoromethyl group, trifluoromethyl group, trifluoroethyl group, pentafluoroethyl group, heptafluoropropyl group, hexafluoroisopropyl group, heptafluoroisopropyl group, hexafluoro-2-methylisopropyl group, perfluoro-2-methylisopropyl group, n-perfluorobutyl group, n-perfluoropentyl group, or perfluorocyclopentyl group is substituted with fluorine.

As the compound represented by the general formula (2), L is more preferably selected₂A fluorine-containing cyclic olefin polymer having an epoxy group or a hydroxyl group capable of cationic polymerization.

When the additive having a photoreactive functional group is a fluorinated cyclic olefin polymer, the additive having a photoreactive functional group may be an additive composed of only one kind of the structural unit represented by the general formula (2), or may be an additive composed of R in the general formula (2)₂～R₅At least 1 two or more kinds of structural units different from each other. Further, the polymer (copolymer) may contain one or more kinds of the structural unit represented by the general formula (2) and a structural unit different from the structural unit represented by the general formula (2).

The fluorine-containing cyclic olefin polymer can be obtained by appropriately applying a known technique. For example, it can be obtained by appropriately applying a known technique relating to ring-opening polymerization of cyclic olefins. Specific examples of polymerization conditions, catalysts used, and the like are described in examples presented later.

The fluorine-containing cyclic olefin polymer represented by the general formula (2) in which the olefin in the main chain is hydrogenated to have a saturated aliphatic structure is preferably selected. The hydrogenation ratio of the main chain olefin is preferably 50 to 100%, more preferably 70 to 100%, and further preferably 90 to 100%.

When the hydrogenation ratio of the main chain olefin is in the above range, light absorption due to the carbon-carbon double bond is suppressed during photocuring, and light can easily reach the deep portion of the resin film. That is, the efficiency of photocuring is improved.

The hydrogenation reaction can be carried out by a known method. The method may be a method using a solid catalyst, a method using a homogeneous catalyst, or a method using 2 or more kinds of these catalysts in combination. A method using a solid catalyst, in which the catalyst can be easily removed by filtration in the post-treatment after the reaction, is preferably selected as appropriate.

The weight average molecular weight (Mw) of the fluorinated cyclic olefin polymer is preferably 500 to 50000, more preferably 500 to 40000, and still more preferably 500 to 30000. By adjusting Mw within this range, compatibility with other components is improved, and a uniform solution can be easily prepared. In addition, the segregation tends to occur efficiently on the surface during film formation.

(photo-curing initiator)

The photocurable composition of the present embodiment preferably contains a photocurable initiator.

Examples of the photo-curing initiator include a photo-radical initiator which generates radicals by light irradiation, and a photo-cation initiator which generates cations by light irradiation.

Among the photo-curing initiators, examples of the photo-radical initiator which generates radicals by light irradiation include acetophenones such as acetophenone, p-tert-butyltrichloroacetophenone, chloroacetophenone, 2-diethoxyacetophenone, hydroxyacetophenone, 2-dimethoxy-2' -phenylacetophenone, 2-aminoacetophenone, and dialkylaminoacetophenone; benzoins such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-2-methylpropan-1-one, and 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one; benzophenones such as benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, hydroxypropyl benzophenone, acryloyl benzophenone, 4' -bis (dimethylamino) benzophenone and the like; thioxanthones such as thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, diethylthioxanthone and dimethylthioxanthone; fluorine-based peroxides such as perfluoro (t-butyl peroxide) and perfluorobenzoyl peroxide; α -acyloxime esters, benzyl- (O-ethoxycarbonyl) - α -monooximes, acylphosphine oxides, glyoxylates (glyyxester), 3-ketocoumarins, 2-ethylanthraquinones, camphorquinones, tetramethylthiuram sulfides, azobisisobutyronitrile, benzoyl peroxides, dialkyl peroxides, t-butylperoxypivalate, and the like. They mostly exhibit their function mainly in the UV region of light wavelengths from 200nm to 400 nm.

Examples of the photo radical initiator to be preferably used include Irgacure 651 (available from Ciba specialty Co., Ltd.), Irgacure 184 (available from Ciba specialty Co., Ltd.), Darocur 1173 (available from Ciba specialty Co., Ltd.), benzophenone, 4-phenylbenzophenone, Irgacure 500 (available from Ciba specialty Co., Ltd.), Irgacure 2959 (available from Ciba specialty Co., Ltd.), Irgacure 127 (available from Ciba specialty Co., Ltd.), Irgacure 907 (available from Ciba specialty Co., Ltd.), Irgacure 369 (available from Ciba specialty Co., Ltd.), Irgacure 819 (available from Ciba specialty Co., Ltd.), Irgacure 1800 (available from Ciba specialty Co., Ltd.), Darocur TPO (available from Ciba specialty Co., Ltd.), Darocur 4265 (available from KT specialty Co., Ltd.), Irgacure XE01 (available from Ciba specialty Co., Ltd.), Irgacure 56 (available from Sega specialty 3683 (available from Ciba specialty Co., Ltd.), Egacure 3683 (available from Ciba specialty Co., Ltd.), and Cure P36100 (available from Ciba specialty Co., Ltd.), and Irgacure F (available from Ciba specialty P) Escapure KT37 (Ningcedi Co., Ltd.), Escapure KTO46 (Ningcedi Co., Ltd.), Escapure 1001M (Ningcedi Co., Ltd.), Escapure KIP/EM (Ningcedi Co., Ltd.), Escapure DP250 (Ningcedi Co., Ltd.), Escapure KB1 (Ningcedi Co., Ltd.), 2, 4-diethylthioxanthone, and the like.

Among these, as the photo radical polymerization initiator to be preferably used further, Irgacure 184 (product of gasoline purification corporation), Darocur 1173 (product of gasoline purification corporation), Irgacure 500 (product of gasoline purification corporation), Irgacure 819 (product of gasoline purification corporation), Darocur TPO (product of gasoline purification corporation), Esacure KIP100F (product of ningbody corporation), Esacure KT37 (product of ningbody corporation), Esacure KTO46 (product of ningbody corporation) and the like can be cited.

The photo-curing initiator is not particularly limited as long as it is a compound that initiates cationic polymerization of the ring-opening polymerizable compound capable of cationic polymerization by light irradiation. Preferably asCation-of which the counter-anion isA compound such as a salt which reacts with light to release a Lewis acid. They mostly exhibit their function mainly in the UV region of light wavelengths from 200nm to 400 nm.

AsAs the cation, for example, diphenyliodine4-methoxy diphenyl iodideBis (4-methylphenyl) iodideBis (4-tert-butylphenyl) iodideBis (dodecylphenyl) iodideTriphenylsulfonium, diphenyl-4-thiophenoxyphenylsulfonium, bis [ 4- (diphenylsulfonium) -phenyl ] sulfide, bis [ 4- (bis (4- (2-hydroxyethyl) phenyl) sulfonium) -phenyl ] sulfide,. eta.5-2, 4- (cyclopentadienyl) [ 1,2,3,4,5, 6-. eta. - (methylethyl) benzene ] -iron (1+) and the like. In addition, in addition toExamples of the cation include perchlorate ion, trifluoromethanesulfonate ion, toluenesulfonate ion, trinitrotoluenesulfonate ion and the like.

On the other hand, examples of the counter anion include tetrafluoroborate, hexafluorophosphate, hexafluoroantimonate, hexafluoroarsenate, hexachloroantimonate, tetrakis (fluorophenyl) borate, tetrakis (difluorophenyl) borate, tetrakis (trifluorophenyl) borate, tetrakis (tetrafluorophenyl) borate, tetrakis (pentafluorophenyl) borate, tetrakis (perfluorophenyl) borate, tetrakis (trifluoromethylphenyl) borate, tetrakis (bistrifluoromethylphenyl) borate, and the like.

Specific examples of the more preferable photocationic initiator include Irgacure 250 (product of Ciba specialty Chemicals), Irgacure 784 (product of Ciba specialty Chemicals), Irgacure 290 (product of BASF Japan), Escapure 1064 (product of Nippodi), CYRAURE UVI6990 (product of Union carbide Japan), Adeka Optomer SP-172 (product of ADEKA), Adeka Optomer SP-170 (product of Asahi Denka Co., Ltd.), Adeka Optomer SP-152 (product of ADEKA), Adeka Optomer SP-150 (product of ADEKA), San-400 (product of San-Apro), CPI-310B (product of San-Apro), CPI-210K (product of San-Apro), CPI-210S (product of Apro), and San-100P (product of San-Apro).

When the photocurable composition of the present embodiment contains a photocurable initiator, only 1 kind of the photocurable initiator may be contained, and 2 or more kinds may be contained.

The content of the photo-curing initiator in the photocurable composition is preferably 0.1 to 20% by mass, and more preferably 1.0 to 15% by mass, based on the entire photocurable composition (100% by mass).

(sensitizer)

The photocurable composition of the present embodiment may contain a sensitizer.

Examples of the sensitizer include anthracene, naphthalene, phenothiazine, perylene, thioxanthone, benzophenone thioxanthone, and the like. Further, as the sensitizing dye, thiopyran can be exemplifiedSalt-based dye, merocyanine-based dye, quinoline-based dye, styrylquinoline-based dye, coumarin ketone-based dye, thioxanthene-based dye, xanthene-based dye, Oxonol-based dye, cyanine-based dye, rhodamine-based dye, pyranSalt-based pigments, and the like. An anthracene-based or naphthalene-based sensitizer is preferable, and the use of the sensitizer in combination with a cationic curing initiator (cationic polymerization initiator) improves sensitivity remarkably. Specific examples of the anthracene-based and naphthalene-based compounds include dibutoxyanthracene, diethoxyanthracene, dipropoxyanthraquinone, bis (octanoyloxy) anthracene, and diethoxynaphthalene.

When a sensitizer is used, the amount of the sensitizer added is preferably 0.01 to 20% by mass, more preferably 0.01 to 10% by mass, and even more preferably 0.01 to 10% by mass, based on the whole photocurable composition of the present embodiment (100%), and a plurality of sensitizers may be used in combination.

(other Components)

The photocurable composition according to the present embodiment may contain components other than those described above.

Examples of the solvent include a solvent, an antioxidant, a leveling agent, a wettability modifier, a surfactant, a modifier such as a plasticizer, an ultraviolet absorber, a preservative, a stabilizer such as an antibacterial agent, a photosensitizer, a silane coupling agent, and the like. For example, a plasticizer is preferable because it may contribute to adjustment of viscosity in addition to the above-described intended effects.

(physical Properties of photocurable composition after curing by light irradiation)

In the nanoimprint process, for example, the following processes are performed: the 2 nd photocurable composition used for processing a substrate to be processed is brought into contact with the uneven surface of a transfer mold containing a photocurable composition (1 st photocurable composition), and UV irradiation is performed while applying pressure to cure the 2 nd photocurable composition and to peel off the composition, thereby forming an uneven structure on the surface of the substrate to be processed. In this process, conventionally, when the replica mold is repeatedly used, there have been problems that adhesion of a resin to the surface of the replica mold, shape destruction of the uneven structure due to external stress, and the like hinder repeated use of the replica mold.

The present inventors have intensively studied the relationship between these problems and the physical properties of the cured resin. As a result, it has been found that when the photocurable composition is used and the surface free energy and resin hardness of the resin surface after photocuring are within the ranges described below, the replica mold can be easily maintained in the initial state even if the replica mold is repeatedly used, and thus a substrate to be processed can be processed satisfactorily.

Hereinafter, the surface free energy and the resin hardness will be specifically described.

i) About surface free energy

In the case of the nanoimprint method using a replica mold, it is considered that adhesion of the resin to the surface of the replica mold can be achieved by appropriately designing the surface energy of the replica mold to be low.

Generally, as a method for understanding a surface state such as surface energy, a contact angle method using a water droplet is generally used. Typically, a substrate surface treated with a fluororesin repels a water droplet, and the angle (contact angle) of the substrate surface to the water droplet exceeds 100 °.

On the other hand, the contact angle of water is as small as several degrees to several tens degrees on the surface of a substrate made of a material modified with a group that easily fuses with water, such as a hydroxyl group. However, in the method of evaluating the surface state of a substrate by the contact angle of water, although qualitative evaluation for obtaining intermolecular force due to hydrogen bonding force can be performed, various forces acting between 2 kinds of substances (between a replica mold and the 2 nd photocurable composition), specifically, hydrogen bonding force, dispersion force, orientation force, induction force, and the like cannot be evaluated.

The present inventors have recognized that even a material having the same water contact angle may have different resin adhesion properties when a replica mold is formed. Based on this knowledge, the inventors of the present invention have further studied and found that the contact angle of water is merely an index showing the relationship with water, and it is generally difficult to determine the compatibility between a replica mold as an organic compound and the 2 nd photocurable composition. As another evaluation method, it was recognized that the free energy of the surface of the resin film after photocuring (hereinafter, also simply referred to as surface free energy) is moderately correlated with the degree of adhesion of the resin when the transfer mold is used.

More specifically, if the surface free energy represented by the sum of the hydrogen bonding force, the dispersing force, the aligning force, and the induction force acting on the surface of the resin film (replica mold) after photocuring is less than a specific value, the residue of the 2 nd photocurable composition is less likely to remain on the fine uneven structure on the surface of the replica mold when the 2 nd photocurable composition is applied, photocured, and peeled off from the surface of the replica mold. On the other hand, if the surface free energy exceeds a specific value, the residue of the 2 nd photocurable composition tends to adhere, and the replica mold tends to deteriorate, and thus the surface free energy cannot be reused. The term "adhesion" used herein means that, even when the surface of the used replica mold is clearly deteriorated, the surface of the replica mold can be visually observed (more specifically, the degree of adhesion of the 2 nd photocurable composition can be understood when the surface is observed by an optical microscope, SEM, or the like).

Quantitatively, the surface free energy of the resin film after photocuring, which is measured as in the following evaluation method 1, is preferably 15mJ/m²～40mJ/m²More preferably 15mJ/m²～38mJ/m²More preferably 15mJ/m²～35mJ/m²。

Free energy at surface is more than 40mJ/m²In the case of (2), as described above, the 2 nd photocurable composition cured by light irradiation adheres to the replica mold. Furthermore, the surface free energy is less than 15mJ/m²In the case of (2), the compatibility with the transfer mold during coating is poor, and the 2 nd photocurable composition is repelled from the surface of the transfer mold. Further, if the pressure is directly applied, and the pressure is irradiated with light and peeled off, for example, a void or the like may be generated due to the loss of the bubble in the escape position.

[ evaluation method 1]

First, a photocurable composition is applied to a substrate to form a photocurable film, and the cured film is obtained by irradiation with ultraviolet light.

Next, the contact angles of water, diiodomethane and 1-bromonaphthalene with respect to the above cured film were measured using a contact angle meter, respectively.

Furthermore, the surface free energy was calculated from Kitazaki-Hata's theory.

Incidentally, in order to sufficiently (substantially completely) cure the photocurable film, light of a sufficient light amount, for example, 2000mJ/cm is irradiated²The cumulative amount of light of (1). The irradiation can be performed by UV light (LED light source) having a wavelength of 365nm or the like. The thickness of the photocurable film in the evaluation method 1 is, for example, about 5 to 6 μm (5.5. + -. 0.5. mu.m).

The surface free energy based on Kitazaki-Hata theory can be calculated by software attached to a commercially available contact angle meter. For the sake of caution, the following theory is presented for Kitazaki-Hata.

If the surface free energy of the cured film to be measured is A, the component of the surface free energy A is a component attributable to the dispersion force (A)_d) Component (A) attributable to orientation (polarity) force_p) And a component (A) attributable to hydrogen bonding force_h) Then A can be represented as in formula (1). (since the intermolecular force due to the induced force in the above description is extremely small, it is ignored in the calculation.)

[ number 1]

A＝A_d+A_p+A_hFormula (1)

Further, if the surface free energy of the liquid 1 is B, the values of the respective components are known₁Surface free energy B₁The component (B) is a component (B) attributable to the dispersing power_1d) Component (B) attributable to orientation (polarity) force_1p) And a component (B) attributable to hydrogen bonding force_1h) Then B is₁Can be expressed as in the formula (2).

[ number 2]

B₁＝B_1d+B_1p+B_1hFormula (2)

Likewise, the surface of the liquid 2 is known if the values of the components are knownFrom can be set as B₂B represents the surface free energy of the liquid 3 having a known value for each component₃Then B is₂And B₃Are represented by the following formulae (3) and (4), respectively.

[ number 3]

B₂＝B_2d+B_2p+B_2hFormula (3)

B₃＝B_3d+B_3p+B_3hFormula (4)

Further, if the contact angle measured by using the cured film to be measured and the liquid 1 is set as θ₁The contact angle between the cured film to be measured and the liquid 2 is represented by θ₂The contact angle between the cured film to be measured and the liquid 3 is represented by θ₃Then, the relationships of the equations (5), (6) and (7) are established among the components of the surface free energy and the values of the contact angle between the cured film to be measured and the liquids 1,2 and 3.

[ number 4]

A is calculated by solving simultaneous ternary linear equations including the above equations (5), (6) and (7)_d、A_pAnd A_h. Then, the surface free energy A of the cured film was calculated from the formula (1).

ii) regarding resin hardness

As a failure mode in the case of repeatedly using the replica mold, in addition to the above-described adhesion of the resin, collapse of the uneven structure on the surface of the replica mold due to a pressure bonding process or the like can be mentioned. For example, in the case of the shape of the wire and the gap, a wire break, a notch of the wire edge, or the like is exhibited. In addition, in the case of the pillar shape, a defect such as a pillar break is shown.

In general, the resin hardness is represented by the degree of scratch in the scratch test, and the pencil hardness represented by the pencil hardness at the time of scratch with a specified pencil rubbing. However, these methods, although applicable to the overall evaluation of a flat surface, for example, cannot be applied to the evaluation of judging the shape retention of the fine uneven structure.

The present inventors have recognized that: the hardness obtained by the nanoimprinting method in which the resin hardness is defined by the repulsive force at that time is an index that appropriately indicates the relationship between the shape retention of the replica mold and the resin hardness, by directly pressing the film surface with an indenter having a shape like a very fine needle.

Specifically, the hardness of the photocurable composition after photocuring, which is measured by the procedure as in the following evaluation method 2, is preferably 0.05GPa to 0.5GPa, more preferably 0.1GPa to 0.5GPa, and still more preferably 0.15GPa to 0.5 GPa. If the ratio exceeds the upper limit, the resin surface becomes hard and brittle, and even in the case of a slight external stress, the uneven shape is chipped and the shape cannot be maintained, and further, the roll bending ratio in the roll-to-roll process cannot be tolerated, and cracks are generated in the uneven shape. Further, when the amount is less than the lower limit, the resin is softened, and the resin is deformed by stress at the time of contact and pressure bonding with the 2 nd photocurable composition, for example, the shape thereof changes to the T-top (top), and the resin may not be peeled off due to the anchor effect.

[ evaluation method 2]

First, a cured film was obtained in the same manner as in the above evaluation method 1.

Next, a berkovich indenter was pressed against the cured film using a nanoindenter, and the hardness was calculated from the detected stress value.

< uneven structure and method for producing same >

The photocurable composition of the present embodiment can be used to produce an uneven structure (e.g., replica mold) including a substrate and a resin layer provided on the substrate and having fine unevenness formed on the surface thereof.

Specific embodiments and manufacturing methods of the substrate will be specifically described below.

For the substrate

The raw material of the substrate is not particularly limited. The substrate is made of, for example, an organic material or an inorganic material. As for the properties of the substrate, for example, a sheet-like, film-like, plate-like or porous substrate can be used.

More specifically, when the substrate is made of an organic material, for example, 1 or 2 or more kinds of various resins such as polyacetal, polyamide, polycarbonate, polyphenylene ether, polybutylene terephthalate, polyethylene terephthalate, polyester such as polyethylene naphthalate, polyolefin such as polyethylene and polypropylene, poly (meth) acrylate, polysulfone, polyether sulfone, polyphenylene sulfide, polyether ether ketone, polyimide, polyether imide, polyvinyl acetyl cellulose, polyvinyl alcohol, polyurethane, polyvinylidene fluoride, polytetrafluoroethylene, hexafluoropropylene-tetrafluoroethylene copolymer, and fluorine resin such as perfluoropropylvinyl ether-tetrafluoroethylene copolymer can be used as a raw material. Then, the raw material is processed by injection molding, extrusion molding, hollow molding, thermoforming, compression molding, or the like, thereby forming a substrate. Examples of the porous substrate include a porous substrate cured in a state of being made porous by a foaming agent, a porous substrate made porous by stretching a non-porous base material, a porous substrate made porous by laser processing, and a nonwoven fabric having a porous structure between fibers.

In another embodiment, the substrate may be a single-layer substrate obtained by curing a photocurable monomer such as (meth) acrylate, styrene, epoxy, or oxetane by light irradiation in the presence of a polymerization initiator, or a substrate obtained by applying such a photocurable monomer to an organic material or an inorganic material.

When the substrate is made of an inorganic material, examples of the constituent material include copper, gold, platinum, nickel, aluminum, silicon, stainless steel, quartz, soda glass, sapphire, carbon fiber, and the like.

The surface of the substrate may be treated to improve the adhesion to the photocurable composition and the cured product thereof, regardless of whether the material constituting the substrate is an organic material or an inorganic material. Examples of such treatment include adhesion treatment such as corona treatment, atmospheric pressure plasma treatment, vacuum plasma treatment, and easy adhesion coating treatment.

The substrate may have a single layer or 2 or more layers regardless of whether the constituent material of the substrate is an organic material or an inorganic material.

The substrate is preferably a resin film. The substrate is preferably, for example, a resin film containing any of the above resins. Since the substrate is not an inorganic material but a resin film, a user can easily cut the substrate into a desired shape and size for use. Further, there is an advantage that the laminate can be wound during storage of the laminate, that is, space can be saved.

From another viewpoint, the substrate preferably has high light transmittance. Thereby, the following advantages can be obtained: in the production or use of the transfer mold, (i) in the production of the uneven structure, light can be irradiated from the substrate side to accelerate the curing reaction, (ii) various steps can be easily visually confirmed, and (iii) the direction of light irradiation can be easily designed freely, thereby improving the degree of freedom in device design.

From the viewpoint of (i), the substrate may preferably have a high transmittance in a wavelength region of light that is reacted with the photo-curing initiator. More preferably, the transmittance of light in the ultraviolet region is high. For example, the transmittance of light having a wavelength of 200nm to 400nm is preferably 50% to 100%, more preferably 70% to 100%, and still more preferably 80% to 100%.

From the viewpoint of (ii), the substrate preferably has a high light transmittance in the visible region. For example, the transmittance of light having a wavelength of 500nm to 1000nm is preferably 50% to 100%, more preferably 70% to 100%, and still more preferably 80% to 100%.

Incidentally, since most of the resin film has high transparency, the resin film is preferably used as the substrate even in terms of light transmittance.

The thickness of the substrate is not particularly limited. The adjustment is appropriately performed according to various purposes, for example, the workability of the laminate, the dimensional accuracy of the uneven structure to be obtained, and the like.

The thickness of the substrate is, for example, 1 to 10000. mu.m, specifically 5 to 5000. mu.m, and more specifically 10 to 1000. mu.m.

The shape of the entire substrate is not particularly limited. For example, the sheet-like shape, the disk-like shape, the roll-like shape, etc. may be used.

For the coating step

The specific steps of the method for producing the uneven structure of the present embodiment are not particularly limited. For example, the method can be produced by a process including the steps of: a step of forming a photocurable composition layer on the surface of a substrate using the photocurable composition of the present embodiment (photocurable layer forming step).

The method for forming the photocurable composition layer is not particularly limited, and typically, first, a photocurable composition is applied onto a substrate by the following application method to form a photocurable layer.

As the coating method, a known method can be applied. Examples thereof include table coating method, spin coating method, dip coating method, die coating method, spray coating method, bar coating method, roll coating method, curtain coating method, slit coating method, blade coating method, spray coating method, dispensing (dispense) method, and the like. These are appropriately selected in consideration of the shape and size of the fine asperities, the size of the replica mold, the productivity, and the like.

When the photocurable composition contains a solvent, a baking (heating) step may be provided after coating as necessary for the purpose of removing the solvent. The conditions such as the baking temperature and time may be appropriately set in consideration of the coating thickness, the process pattern, and the productivity. The temperature is preferably 20 to 200 ℃, more preferably 20 to 180 ℃, and the time is preferably 0.5 to 30 minutes, more preferably 0.5 to 20 minutes.

The baking method may be direct heating by a hot plate or the like; passing it through a hot blast stove; an infrared heater or the like is used.

The thickness of the photocurable layer provided on the substrate is preferably 0.05 μm to 100 μm, more preferably 0.10 μm to 80 μm, and still more preferably 0.20 μm to 50 μm. By setting the thickness of the photocurable layer to the above range, photocuring of the photocurable composition can be efficiently performed in replica molding. In addition, for example, when a roll-to-roll process is considered, even if a bending stress corresponding to a bending ratio of a roll of a winding transfer mold is applied, the transfer mold can be used in a good state without generating a crack or the like.

Concerning the crimping step

The uneven surface of the mold having the uneven structure on the surface thereof is pressure-bonded to the photocurable layer formed on the substrate by the above-described method. Thereby, the uneven pattern corresponding to the uneven surface of the mold is transferred to the photocurable layer. Incidentally, the mold here is a mold designed according to the concave-convex processing of the substrate to be processed, specifically, a master mold.

The shape of the mold (master mold) is not particularly limited. The shape of the convex portion and the concave portion of the mold may be dome-shaped, quadrangular prism-shaped, cylindrical, prism-shaped, quadrangular pyramid-shaped, triangular pyramid-shaped, polyhedral, hemispherical, or the like. The cross-sectional shapes of the convex portion and the concave portion of the mold include a cross-sectional quadrangle, a cross-sectional triangle, a cross-sectional semicircle, and the like.

The width of the convex and/or concave portions of the mold (master mold) is not particularly limited, but is, for example, 10nm to 100 μm, preferably 20nm to 70 μm. The depth of the recessed portion and/or the height of the projecting portion are not particularly limited, but are, for example, 10nm to 100 μm, preferably 20nm to 70 μm. Further, the aspect ratio, which is the ratio of the width of the convex portion to the height of the convex portion, is preferably 0.1 to 500, and more preferably 0.5 to 20.

Examples of the material of the mold (master mold) include metal materials such as nickel, iron, stainless steel, germanium, titanium, and silicon; inorganic materials such as glass, quartz, and alumina; resin materials such as polyimide, polyamide, polyester, polycarbonate, polyphenylene oxide, polyphenylene sulfide, polyacrylate, polymethacrylate, polyarylate, epoxy resin, and silicone resin; carbon materials such as diamond and graphite.

The crimping method can be performed by a known method. For example, a method of bringing the photocurable composition layer into contact with the uneven pattern of the mold and pressing the layer with an appropriate pressure in this state is exemplified.

The upper limit of the pressure is not particularly limited. The upper limit of the pressure is, for example, preferably 10MPa or less, more preferably 5MPa or less, and particularly preferably 1MPa or less. The pressure is appropriately selected according to the pattern shape, aspect ratio, material, and the like of the mold. There is also no particular lower limit to the pressure. The photocurable composition layer may be filled into each corner in correspondence with the concave-convex pattern of the mold. The upper limit of the pressure is, for example, 0.1MPa or more.

The pressure bonding step may be performed under the atmosphere, or may be performed under vacuum, under an inert gas such as nitrogen, or under a fluorine gas atmosphere. The amount of the solvent is appropriately selected depending on the purpose of, for example, curability of the photocurable composition, degassing such as ventilation, and improvement in filling rate of the photocurable composition.

Light irradiation step

In the light irradiation step, the photocurable layer is irradiated with light. More specifically, the photocurable layer is directly irradiated with light in a state where pressure is applied in the pressure bonding step (in a state where the mold is pressure bonded). And curing the photocurable layer.

The light to be irradiated is not particularly limited as long as it is light capable of curing the photocurable composition layer. Specific examples thereof include ultraviolet rays, visible rays, and infrared rays. Among these, light that generates radicals or ions from the photo-curing initiator is preferable.

Specifically, a light source that generates light having a wavelength of 400nm or less can be used, and for example, a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a chemical lamp, a black light lamp, a microwave-excited mercury lamp, a metal halide lamp, an i-ray, a g-ray, a KrF excimer laser, an ArF excimer laser, or the like can be used.

Light irradiationThe cumulative light amount of (2) can be set to, for example, 3mJ/cm²～10000mJ/cm²。

The light irradiation may be performed from either the back surface of the substrate on which the photocurable composition layer is formed or from the opposite surface of the mold (master mold) to the surface on which the uneven structure is formed. In particular, the material may be selected as appropriate in consideration of the substrate and the material of the mold (light transmittance, etc.).

For the purpose of promoting curing of the photocurable composition layer, etc., light irradiation and heating may be used together. And/or the heating step may be performed after the light irradiation step.

The heating temperature is preferably from room temperature (usually 25 ℃) to 200 ℃ inclusive, and more preferably from room temperature to 150 ℃ inclusive. The heating temperature may be appropriately selected in consideration of heat resistance of the substrate, the photocurable composition layer, and the mold, improvement in productivity due to acceleration of curing, and the like.

Regarding the peeling step

The method for manufacturing the uneven structure according to the present embodiment preferably includes a mold peeling step. Specifically, the photocurable layer cured in the light irradiation step is separated from the mold, and the uneven structure having the uneven pattern formed on the substrate is obtained.

As the method of mold release, a known method can be applied. For example, the resin layer formed on the substrate can be peeled from the mold with the end of the substrate as a starting point. Further, a tape having adhesiveness may be attached to the substrate, and the resin layer formed on the substrate may be separated from the mold using the tape as a starting point. Further, when the method is performed by a continuous method such as roll-to-roll method, the method may be a method of rotating a roll at a speed corresponding to the peripheral speed of the step and peeling the resin layer formed on the substrate and the uneven structure having the uneven pattern formed thereon while winding the resin layer and the uneven structure.

Through the above steps, an uneven structure in which the unevenness of the mold (master mold) is reversed can be manufactured.

(method of Using replica mold)

The method of using the replica mold is not particularly limited. For example, the present invention can be used in the same manner as the above-described method for producing a replica mold. In this case, the mold referred to as a master mold is replaced with a mold (replica mold) having an uneven structure on the surface after curing the photocurable composition (1 st photocurable composition) of the present embodiment. Further, as the photocurable composition (2 nd photocurable composition), a material having characteristics corresponding to a processing method of a substrate to be processed and various applications (for example, etching resistance, transparency, hardness, gas permeability, and the like) is selected.

Further, a replica mold comprising the photocurable composition of the present invention can be reused for the same material (1 st photocurable composition). For example, 50 transfer molds were produced from the transfer mold using the 1 st photocurable composition, and 100 substrates were processed using the 2 nd photocurable composition using each transfer mold. This enables 5000 (50 × 100) sheets of substrates to be processed, and enables efficient production of products while preventing deterioration of the transfer mold.

For example, if the processing of the substrate to be processed is described as a circuit formation example, a method of forming a groove for embedding copper on the surface of a silicon wafer can be exemplified. Specifically, the following is described.

First, a photocurable composition having etching resistance is applied to a silicon wafer by a method such as spin coating, the replica mold of the present invention is pressed against the silicon wafer, and the photocurable composition is cured and peeled off by light irradiation. Next, the concave-convex structure formed on the silicon wafer is masked, and the surface of the silicon wafer is processed by a dry etching method to form the concave-convex structure. Then, copper is embedded to complete the circuit.

In such a process, if the transfer mold can be repeatedly used, the number of the substrates to be processed and the area of the substrates to be processed can be increased for each transfer mold, and productivity can be improved.

In short, the productivity of nanoimprinting can be improved by forming a fine uneven pattern by repeatedly using, as a replica mold, a substrate provided with a resin layer having fine unevenness formed on the surface thereof, which is formed from the photocurable composition of the present embodiment. That is, by using the photocurable composition of the present embodiment, a UV nanoimprint process with high productivity can be industrially realized.

Further, as recognized by the present inventors, the photocurable composition of the present embodiment has a feature that the applicable range of the pattern shape from the nano size to the micro size is wide. Thus, the photocurable composition of the present embodiment can be preferably applied to applications other than a transfer mold (various fine uneven patterns can be favorably formed from 1 photocurable composition), in addition to applications of a transfer mold.

Although the embodiments of the present invention have been described above, they are merely illustrative of the present invention and various configurations other than the above-described configurations can be adopted. The present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within a range in which the object of the present invention can be achieved are also included in the present invention.

Examples

Embodiments of the present invention will be described based on examples. The present invention is not limited to the examples.

First, the following description will be made.

Analysis method of commercially available product and synthesized photocurable additive and adhesive resin

Method for measuring surface free energy (evaluation method 1), method for measuring hardness (evaluation method 2)

Mold, apparatus, evaluation/analysis method, and the like used in nanoimprint process

[ weight average z (Mw) and molecular weight distribution (Mw/Mn) ]

The molecular weights of the commercial products and additives shown in the synthetic examples, which were proposed later, were measured by Gel Permeation Chromatography (GPC). Specifically, the weight average molecular weight (Mw) and the number average molecular weight (Mn) of a polymer dissolved in Tetrahydrofuran (THF) were measured by correcting the molecular weights with polystyrene standards using the following conditions.

The detector: RI-2031 and 875-UV manufactured by Japan Spectroscopy

A series connection column: shodex K-806M, 804, 803, 802.5

Column temperature: 40 deg.C

Flow rate: 1.0 ml/min

Sample concentration: 3.0-9.0 mg/mL

[ hydrogenation ratio of fluorinated cyclic olefin Polymer ]

The powder of the additive subjected to hydrogenation reaction was dissolved in deuterated tetrahydrofuran. For which the passing of 270MHz-¹H-NMR measurement was carried out to obtain an integral value of signals of hydrogen bonded to the double bond carbon of the main chain at δ of 4.5 to 7.0ppm, and the hydrogenation ratio was calculated from the integral value.

When no signal of hydrogen derived from a double bond of a main chain is observed in a region where δ is 4.5 to 7.0ppm, the hydrogenation ratio is set to 100%.

[ evaluation method 1: method for measuring surface free energy

The photocurable composition was formed into a film on a PET film substrate (Lumiror U34, thickness 188 μm, manufactured by Toray corporation) by using a bar coater. In the case where the photocurable composition contains a solvent, a drying treatment is subsequently performed on a hot plate at 100 ℃ for 1 minute. Thus, a photocurable film was formed.

Then, at 2000mJ/cm²The photocurable film was cured by irradiation with UV light (LED light source) having a wavelength of 365nm at the cumulative light quantity to produce a sample for measuring surface free energy having a uniform surface thickness of 5 to 6 μm.

The contact angle of the sample surface was measured using a contact angle meter (type A-XE) manufactured by Kyowa interfacial chemical Co., Ltd., using water, diiodomethane, and 1-bromonaphthalene as standard test liquids.

In order to calculate the surface free energy, the surface free energy is calculated by the above-described method based on the Kitazaki-Hata theory using the known surface free energy of the standard test liquid and the measured value of the contact angle of the standard test liquid on the specimen. Specifically, the calculation was performed using FAMAS (product of Kyowa interface chemical Co., Ltd.) as an application software attached to a contact angle meter.

The numerical values described in the examples are average values of results obtained by performing 5 identical tests on 1 sample.

[ evaluation method 2: method for measuring hardness

First, a photocurable film was formed and irradiated with light in the same manner as in evaluation method 1 to obtain a cured film of a photocurable composition.

Next, the resin hardness was measured by an indentation test according to ISO14577, which is a standard of the nanoimprint method, using a nanoindenter (TI-950Tribo index, manufactured by Hysitron inc. And pressing a Berkovich indenter on the cured film to a depth of 200nm, and calculating the hardness (GPa) at the room temperature of 23-25 ℃ according to the detected stress value.

The numerical values described in the examples are average values of results obtained by performing 5 identical tests on 1 sample.

[ mold used (corresponding to the master mold) ]

A quartz mold having a linear pattern of lines (convex portions) and gaps (concave portions) was used.

Specifically, the following mold a and mold B were used, assuming that the width of the convex portion was L1, the width of the concave portion was L2, and the height of the convex portion was L3.

Mold a: 450nm for L1, 450nm for L2, 450nm for L3

Mold B: 75nm for L1, 75nm for L2, 150nm for L3

[ apparatus for producing uneven Structure ]

The pressure bonding of the photocurable composition (photocurable film) and the mold and the subsequent UV irradiation were carried out using a UV nanoimprint apparatus X-100U (SCIVAX). The UV light source is a UV-LED light source with a wavelength of 365 nm.

[ measurement of the size of the convex part ]

The measurement of the uneven structure was carried out using a scanning electron microscope JSM-6701F (manufactured by Nippon spectral Co., Ltd., hereinafter, referred to as SEM). For the measurement of the width of the convex portion, the line width at any 5 positions of the pattern surface was measured, and the average value of the obtained 5 values was used as the convex portion width.

[ evaluation of the projection size when repeatedly used as a replica mold ]

In order to evaluate the deterioration of the mold due to repeated use, the projection width of the used replica mold was measured by SEM at the time of mold production, at the time of use 1 time, and at the time of use 10 times. In table 2, which is proposed later, the measured values of the widths of the convex portions after 50 times of use are described unless otherwise specified.

Hereinafter, a method for synthesizing an additive having a photoreactive functional group and a binder resin, a method for preparing a photocurable composition, and evaluation results will be described.

Synthesis example 1 Synthesis of additive (C-1)

First, 5, 6-trifluoro-6- (trifluoromethyl) bicyclo [2.2.1] was prepared as a fluorine-containing cyclic olefin monomer]Hept-2-ene (100g) and 1, 2-epoxy-5-hexene (5.675g) in tetrahydrofuran. To this solution, Mo (N-2, 6-Pr) was addedⁱ ₂C₆H₃)(CHCMe₂Ph)(OBut)₂(85mg) in tetrahydrofuran, and ring-opening metathesis polymerization was carried out at 70 ℃.

Then, the olefin portion of the obtained polymer was hydrogenated using palladium alumina (5g) as a solid catalyst at 160 ℃ for 24 hours to hydrogenate the olefin in the main chain.

The obtained solution was subjected to pressure filtration using a filter having a pore size of 0.5 μm to remove palladium alumina, the obtained solution was discharged to a methanol/hexane (50% by mass/50% by mass) mixed solution, and a white polymer was separated by filtration and dried.

As a result, 95g of a white powdery polymer (additive (C-1)) was obtained.

By¹H-NMR showed that the additive (C-1) had a hydrogenation rate of 100%, and that L was in the structure represented by the general formula (2)₂Contains an aliphatic structure containing a hydroxyl group in which an epoxy group is reduced by hydrogen. The weight average molecular weight (Mw) was 6050, and the molecular weight distribution (Mw/Mn) was 1.49.

Synthesis example 2 Synthesis of additive (C-2)

First, ring-opening metathesis polymerization was carried out in the same manner as in synthesis example 1 except that the kind of the monomer was changed to 5, 6-difluoro-5-trifluoromethyl-6-perfluoroethylbicyclo [2.2.1] hept-2-ene.

Followed byAs the olefin portion of the obtained polymer, (Ph) as a homogeneous catalyst was used₃P)₃CORuHCl, at 125 degrees C, 24 hours under the conditions of hydrogenation reaction, the main chain olefin hydrogenation.

Then, the resulting solution was discharged into methanol, and a white polymer was separated by filtration and dried to obtain 98g of a white powdery polymer (additive (C-2)).

By¹H-NMR showed that the hydrogenation ratio of the additive (C-2) was 100%, and L in the structure represented by the general formula (2)₂Contains an aliphatic structure containing epoxy groups. The weight average molecular weight (Mw) was 6200, and the molecular weight distribution (Mw/Mn) was 1.51.

Synthesis example 3 Synthesis of Binder resin (B-1)

First, 5, 6-trifluoro-6- (trifluoromethyl) bicyclo [2.2.1] was prepared]Hept-2-ene (100g) and 1-hexene (0.298mg) in tetrahydrofuran. To this solution, Mo (N-2, 6-Pr) was addedⁱ ₂C₆H₃)(CHCMe₂Ph)(OBut)₂(50mg) in tetrahydrofuran, and ring-opening metathesis polymerization was carried out at 70 ℃.

Next, the olefin portion of the obtained polymer was hydrogenated with palladium alumina (5g) at 160 ℃ to obtain a tetrahydrofuran solution of poly (1,1, 2-trifluoro-2-trifluoromethyl-3, 5-cyclopentylideneethylene). The resulting solution was subjected to pressure filtration using a filter having a pore size of 5 μm to remove palladium alumina.

Then, the resulting solution was added to methanol, and the white polymer was separated by filtration and dried. Thus, 99g of a binder resin (B-1) which was a fluorinated cyclic olefin polymer having no reactive functional group was obtained. The binder resin (B-1) had a hydrogenation rate of 100%, a weight-average molecular weight (Mw) of 70000 and a molecular weight distribution (Mw/Mn) of 1.71.

Example 1 preparation of photocurable composition (1), production of replica mold, and the like

First, a solution was prepared by adding 0.05g of X-22-2000 (manufactured by shin-Ethernon Co., Ltd.) and 1g of CPI-310B (manufactured by San-Apro Co., Ltd.) as a photo-curing initiator to 10g of a mixture of bis (3-ethyl-3-oxetanylmethyl) ether and 3, 4-epoxycyclohexylmethyl-3 ', 4' -epoxycyclohexanecarboxylate as a photo-curing monomer in a mass ratio of 7/3.

(for X-22-2000, R is represented in the general formula (1)₁Methyl, L₁Epoxy, methyl and phenyl groups, and a molecular weight (Mw) of 7300. )

Then, the solution was subjected to pressure filtration using a filter having a pore size of 1 μm, and further subjected to filtration using a filter having a pore size of 0.1 μm. Thus, a photocurable composition (1) was prepared.

Using the obtained photocurable composition (1), a resin film cured with an LED light source was produced according to evaluation methods 1 and 2, and evaluated. The surface free energy is 26.2mJ/m²The surface hardness was 0.28 GPa.

After the photocurable composition (1) was formed into a film on a PET substrate by the same method as in evaluation method 1, the mold a or the mold B was pressed against the atmosphere at a pressure of 0.2MPa gauge using the nanoimprint apparatus described above. While maintaining the state of pressure application, the thickness of the film was 2000mJ/cm from the back surface side of the PET film substrate²The light irradiation is performed to cure the photocurable composition (1).

The cured film formed on the PET film substrate was peeled off from the mold to obtain a replica mold a-1 (made of quartz mold a) or a replica mold B-1 (made of quartz mold B) having a line and space structure on the surface.

The width of the convex portion of the replica mold thus produced was measured by SEM. Replica mode A-1 was 449nm, and replica mode B-1 was 74 nm.

Further, the cross section of the replica B-1 was cut out, and the states of the element ions in the cross section were mapped by time of flight secondary ion mass spectrometry (TOF-SIMS). As a result, a cross-sectional state of 2 layers was observed, and in the atmospheric air side of the 2 layers, anions containing a fragment of silicon of X-22-2000 (shown in FIG. 1) belonging to the additive were detected.

Example 2 preparation of Photocurable composition (2), production of replica mold, and the like

A solution was prepared by adding 0.5g of the additive (C-1) synthesized in Synthesis example 1 and 0.95g of CPI-310B (San-Apro) as a photocurable initiator to 9.5g of a mixture of bis (3-ethyl-3-oxetanylmethyl) ether and 3, 4-epoxycyclohexylmethyl-3 ', 4' -epoxycyclohexanecarboxylate in a mass ratio of 7/3 as a photocurable monomer.

Subsequently, a photocurable composition (2) was prepared in the same manner as in example 1.

Using the obtained photocurable composition (2), a resin film cured with an LED light source was produced according to evaluation methods 1 and 2, and evaluated. The surface free energy is 32.0mJ/m²The hardness was 0.22 GPa.

The replica mold A-2 produced in the same manner as in example 1 had a projection width of 449nm, and the replica mold B-2 had a projection width of 73 nm.

EXAMPLE 3 preparation of Photocurable composition (3), production of replica mold, and the like

A photocurable composition (3) was prepared in the same manner as in example 1, except that 0.1g of X-22-2000 (manufactured by shin-Etsu Silicone Co.) and 0.05g of additive (C-1) were used as additives.

Using the obtained photocurable composition (3), a resin film cured with an LED light source was produced according to evaluation methods 1 and 2, and evaluated. The surface free energy is 36.8mJ/m²The hardness was 0.25 GPa.

The replica mold A-3 produced in the same manner as in example 1 had a convex width of 450nm and the replica mold B-3 had a convex width of 75 nm.

Example 4 preparation of photocurable composition (4), production of replica mold, and the like

To 10g of limonene dioxide as a photocurable monomer, 0.1g of BY16-876 (manufactured BY Toray Corning Co.) and 0.05g of additive (C-1), 0.5g of CPI-310B (manufactured BY San-Apro Co.) and 0.1g of sensitizer (Anthracure UVS-1331, manufactured BY Kawasaki chemical Co.) were added as additives.

(about BY16 to 876, wherein R is represented by the formula (1)₁Methyl, L₁Epoxy, methyl and polyether groups, molecular weight (Mw) 25000. )

Subsequently, a photocurable composition (4) was prepared in the same manner as in example 1.

Using the obtained photocurable composition (4), a resin film cured with an LED light source was produced according to evaluation methods 1 and 2, and evaluated. The surface free energy is 33.2mJ/m²The hardness was 0.24 GPa.

The replica mold A-4 produced in the same manner as in example 1 had a projection width of 448nm and the replica mold B-4 had a projection width of 74 nm.

EXAMPLE 5 preparation of Photocurable composition (5), production of replica mold, and the like

A solution was prepared by adding 2.5g of the binder resin (B-1) synthesized in Synthesis example 3, 0.05g of X-22-2000 (manufactured by shin-Etsu Silicone Co., Ltd.) as an additive, and 1g of CPI-310B (manufactured by San-Apro Co., Ltd.) as a photo-curing initiator to 10g of a mixture of bis (3-ethyl-3-oxetanylmethyl) ether and 3, 4-epoxycyclohexylmethyl-3 ', 4' -epoxycyclohexanecarboxylate as a photo-curable monomer in a mass ratio of 7/3.

Subsequently, a photocurable composition (5) was obtained by adjusting in the same manner as in example 1.

Using the obtained photocurable composition (5), a resin film cured with an LED light source was produced according to evaluation methods 1 and 2, and evaluated. The surface free energy is 34.2mJ/m²The hardness was 0.23 GPa.

The replica mold A-5 produced in the same manner as in example 1 had a convex width of 450nm and the replica mold B-5 had a convex width of 74 nm.

EXAMPLE 6 preparation of Photocurable composition (6), production of replica mold, and the like

A photocurable composition (6) was obtained in the same manner as in example 2, except that the additive (C-2) synthesized in synthesis example 2 was used as the additive.

Using the photocurable combinations obtainedThe resin film cured with an LED light source was produced and evaluated for (6) according to evaluation methods 1 and 2. The surface free energy is 28.5mJ/m²The hardness was 0.25 GPa.

The replica mold A-6 produced in the same manner as in example 1 had a projection width of 448nm and the replica mold B-6 had a projection width of 74 nm.

EXAMPLE 7 preparation of Photocurable composition (7), production of replica mold, and the like

A photocurable composition (7) was obtained in the same manner as in example 3, except that X-22-2000 (manufactured by shin-Etsu Silicone Co., Ltd.) as an additive of the photocurable composition (3) in example 3 was changed to FM-DA11 (manufactured by JNC Co., Ltd.).

Using the obtained photocurable composition (7), a resin film cured with an LED light source was produced according to evaluation methods 1 and 2, and evaluated. The surface free energy is 25.7mJ/m²The hardness was 0.27 GPa.

The replica mold A-7 produced in the same manner as in example 1 had a projection width of 448nm and the replica mold B-7 had a projection width of 74 nm.

[ evaluation of reusability of different kinds of materials as a replica mold ]

Evaluation examples of repeated use using the replica mold A-1 and the replica molds (A-2 to A-7) produced in examples 2 to 7:

first, a hydrophilized alkali-free glass substrate, which was hydrophilized by a nitrogen atmospheric pressure plasma treatment so that the water contact angle was 4 ° or less, was prepared.

Then, a commercially available nanoimprint material (PAK-01, manufactured by toyoyo synthesis) was applied as a2 nd photocurable composition on the substrate by a spin coating method.

The uneven surface of the replica mold A-1 was pressed against the coating film surface obtained above with the nanoimprint apparatus at a gage pressure of 0.2 MPa. Under the condition of maintaining the pressure, 6000mJ/cm is formed from the back side of the transfer mold²The accumulated light quantity of (2) is irradiated with light to cure the coating film. Then, peeling offThe transfer body A-1 (produced from the transfer mold A-1) formed of the 2 nd photocurable composition and having the uneven structure formed on the surface thereof was obtained by separating the transfer mold A-1.

The reusability of the replica mold A-1 was evaluated by repeating the above-described steps from the application of the 2 nd photocurable composition onto an alkali-free glass substrate to the release of the replica mold A-1.

The width of the projection of replica A-1 after repeated use for 50 times was measured by SEM and found to be 449 nm. That is, the width of the projection does not vary during production (before use as a replica mold).

Evaluation example of reuse using the replica mold B-1 produced in example 1 and the replica molds (B-2 to B-7) produced in examples 2 to 6:

each replica was used 50 times in the same manner as in the above replica A-1 except that the replica used was replaced. The width of the convex portion of the used replica mold was measured, and as a result, the width of the convex portion was not changed in any of the replica molds at the time of production.

From the above, it was found that the photocurable composition used was reusable even when it was the same as the material used for the replica mold. That is, the replica mold can be reused for different kinds of materials.

[ evaluation of reusability of the same Material as a replica mold ]

Evaluation example of reuse using the replica mold a-1 produced in example 1 and the replica molds (a-2 to a-7) produced in examples 2 to 7:

the photocurable composition (1) used in example 1 was applied to a PET substrate as the 2 nd photocurable composition by a spin coating method.

The uneven surface of the replica mold A-1 was pressed against the coated film surface obtained above at a gage pressure of 0.2MPa using the nanoimprint apparatus. Under the condition of maintaining the pressure, 6000mJ/cm is formed from the back side of the transfer mold²The accumulated light quantity of (2) is irradiated with light to cure the coating film. Then, the replica mold A-1 was peeled off to obtain a photocurable composition having a textured structure formed on the surface thereof, which was a2 nd photocurable composition and was a same material, (2) ((1) The transfer body A-1 (made of a transfer mold A-1) was formed.

The reusability of the replica mold a-1 was evaluated by repeating the above-described steps from application of the photocurable composition (1) used in example 1 as the 2 nd photocurable composition to peeling off of the replica mold a-1.

The width of the projection of replica A-1 after repeated use for 50 times was measured by SEM and found to be 449 nm. That is, the width of the projection does not change during production (before use as a transfer mold), and there is no problem in appearance.

Each replica was used 50 times in the same manner as in the above replica A-1 except that the replica used was replaced. The width of the protruding portion of the transfer mold after repeated use was measured, and as a result, the protruding portion width at the time of production did not change in any transfer mold, and there was no problem in appearance.

Evaluation example of reuse using the replica mold B-1 produced in example 1 and the replica molds (B-2 to B-7) produced in examples 2 to 6:

each replica was used 50 times in the same manner as in the above replica A-1 except that the replica used was replaced. The width of the protruding portion of the transfer mold after repeated use was measured, and as a result, the protruding portion width at the time of production did not change in any transfer mold, and there was no problem in appearance.

From the above, it was found that the photocurable composition used was reusable even when it was the same as the material used for the replica mold. That is, the replica mold can be reused for the same material.

Comparative example 1 preparation of Photocurable composition (8), etc

A solution was prepared by adding 0.2g of Irgacure 184 (manufactured by BASF Japan) as a photo-curing initiator to 10g of methyl methacrylate as a photo-curable monomer. Subsequently, a photocurable composition (7) was prepared in the same manner as in example 1.

Using the obtained photocurable composition (8), a resin film cured with an LED light source was produced according to evaluation methods 1 and 2, and evaluated. Surface selfEnergy of mixing is 42.7mJ/m²The hardness was 0.35 GPa.

The replica mold A-8 produced in the same manner as in example 1 had a convex width of 405nm and the replica mold B-8 had a convex width of 68 nm.

Further, reusability was evaluated in the same manner as in [ evaluation of reusability for different types of materials as a replica mold ] described above. Both of the transfer mold A-8 and the transfer mold B-8 were residues of the 2 nd photocurable composition adhered to the transfer mold after 1 use to a degree visually recognizable. Further, as a result of SEM observation, residues of the 2 nd photocurable composition were adhered between the filling lines.

Further, the reusability was evaluated in the same manner as in [ evaluation of reusability of the same material as the replica mold ], but at the moment when the replica mold a-8 or the replica mold B-8 was brought into contact with the photocurable composition (8), the cured resin layer of the replica mold dissolved, and the next step could not be performed. I.e. not reusable for the same material.

Comparative example 2 preparation of Photocurable composition (9)

A solution was prepared by adding 0.4g of Irgacure 184 (manufactured by BASF chemical Co., Ltd.) as a photo-curing initiator to 10g of a mixture of pentaerythritol triacrylate KAYARAD-PET-30 (manufactured by Nippon Chemicals) and a multifunctional acrylate polymer BS371 (manufactured by Mitsuwa chemical Co., Ltd.) in a mass ratio of 4/1 and dissolving the mixture in 10g of a mixture of methyl acetate and Methyl Ethyl Ketone (MEK) in a mass ratio of 3/2. Subsequently, the mixture was filtered in the same manner as in example 1 to prepare a photocurable composition (9).

Using the obtained photocurable composition (9), a resin film cured with an LED light source was produced according to evaluation methods 1 and 2, and evaluated. The surface free energy is 37.7mJ/m²The hardness was 0.83 GPa.

The replica mold A-9 produced in the same manner as in example 1 had a convex width of 415nm, and the replica mold B-9 had a convex width of 69 nm.

Further, reusability was evaluated in the same manner as in [ evaluation of reusability of a replica mold for different types of materials ]. In both of the replica molds a-9 and B-9, no residue adhesion of the 2 nd photocurable composition was observed by SEM observation on the surface of the replica mold after 1 use. However, the wire was cracked, and after 10 uses, breakage occurred in many places of the wire.

Further, reusability was evaluated by the same method as described above [ evaluation of reusability of the same material as a replica mold ]. In both of the transfer mold A-9 and the transfer mold B-9, no residue of the photocurable composition (9) was observed to adhere after 1 use, but the strand was cracked, and after 10 uses, the strand was broken at a plurality of places.

Comparative example 3 preparation of Photocurable composition (10), etc

A photocurable composition (1) as described in example 1 was prepared without X-22-2000 (manufactured by shin-Etsu Silicone Co., Ltd.) as an additive, and then filtered in the same manner as in example 1. Thus, a photocurable composition (10) was prepared.

Using the obtained photocurable composition (10), a resin film cured with an LED light source was produced according to evaluation methods 1 and 2, and evaluated. The surface free energy is 41.3mJ/m²The hardness was 0.27 GPa.

The replica mold A-10 produced in the same manner as in example 1 had a projection width of 425nm and the replica mold B-10 had a projection width of 71 nm.

Further, reusability was evaluated in the same manner as in [ evaluation of reusability of a replica mold for different types of materials ]. Both of the transfer mold A-10 and the transfer mold B-10 were residues to which the 2 nd photocurable composition was attached to a degree visually recognizable after 3 times of use. Further, as a result of SEM observation, residues of the 2 nd photocurable composition were adhered between the filling lines.

Further, the reusability was evaluated in the same manner as in [ evaluation of reusability of the same material as a replica mold ]. After the replica mold A-10 or the replica mold B-10 was brought into contact with the photocurable composition (10) and cured by UV irradiation, the mold was tried to be peeled off, but they were firmly adhered and could not be peeled off. I.e. not reusable for the same material.

The composition information (compounding ingredients), surface free energy and hardness, and evaluation results as reusability of a replica mold of the photocurable composition are summarized and shown in tables 1 and 2.

[ Table 1]

[ Table 2]

TABLE 2

In the column of "determination" in table 2, the results of SEM observation after the use of the replica after 50 times of use show that the shapes of the uneven structures of the replicas a and B do not change, and the case where the line width does not change from the time of replica production is evaluated as good (good), and the case where the resin is adhered (not measurable) or has a fracture is evaluated as x (poor).

From the above, it is understood that the transfer mold produced from the photocurable composition of example 1 has good reusability. That is, even when the photocurable composition was used at least 50 times, no adhesion of residue on the surface was observed in the 2 nd photocurable composition, and further, the deterioration of the transfer mold such as breakage of the wire was suppressed, and the composition could be repeatedly used.

The application claims priority on the basis of Japanese application special application No. 2019-129863, which is applied on 7/12/2019, and the entire disclosure of the priority is incorporated into the application.